Decapod crustaceans from rocky shore at Farol Island, Matinhos, Paraná, Brazil. I: temporal distribution of population densities

OpenAIRE

Masunari, Setuko; Oliveira, Edinalva; Kowalczuk, Vânia Graciele Lezan

1998-01-01

A study of the temporal distribution of the decapod populations from a rocky shore at Farol Isle, Matinhos, State of Paraná, Brazil (25o51'S e48o32'W) was carried out. The rocky shore is 13m wide when the tidal level is zero meter and about 8o inclination. In the supralittoral, the rocky basins is mostly covered by a layer of litter coming from the terrestrial environment. In the midlittoral and upper infralittoral, the rocky slope is overlayed by boulders and pebbles and they constitute a hi...

Mapping critical loads of nitrogen deposition for aquatic ecosystems in the Rocky Mountains, USA

International Nuclear Information System (INIS)

Nanus, Leora; Clow, David W.; Saros, Jasmine E.; Stephens, Verlin C.; Campbell, Donald H.

2012-01-01

Spatially explicit estimates of critical loads of nitrogen (N) deposition (CL Ndep ) for nutrient enrichment in aquatic ecosystems were developed for the Rocky Mountains, USA, using a geostatistical approach. The lowest CL Ndep estimates ( −1 yr −1 ) occurred in high-elevation basins with steep slopes, sparse vegetation, and abundance of exposed bedrock and talus. These areas often correspond with areas of high N deposition (>3 kg N ha −1 yr −1 ), resulting in CL Ndep exceedances ≥1.5 ± 1 kg N ha −1 yr −1 . CL Ndep and CL Ndep exceedances exhibit substantial spatial variability related to basin characteristics and are highly sensitive to the NO 3 − threshold at which ecological effects are thought to occur. Based on an NO 3 − threshold of 0.5 μmol L −1 , N deposition exceeds CL Ndep in 21 ± 8% of the study area; thus, broad areas of the Rocky Mountains may be impacted by excess N deposition, with greatest impacts at high elevations. - Highlights: ► Critical loads maps for nutrient enrichment effects of nitrogen deposition. ► Critical load estimates show spatial variability related to basin characteristics. ► Critical loads are sensitive to the nitrate threshold value for ecological effects. ► Broad areas of the Rocky Mountains may be impacted by excess nitrogen deposition. - Critical loads maps for nutrient enrichment effects of nitrogen deposition show that broad areas of the Rocky Mountains may be impacted by excess nitrogen deposition.

Edward Settle | NREL

Science.gov (United States)

Settle Photo of Edward Settle Edward Settle Senior Project Leader - Financing Edward.Settle energy microgrid project. He has more than 25 years of experience providing leadership and advisory projects. Research Interests Energy project finance Energy project tax matters Microgrids Resiliency

Characterization and modeling of sediment settling, consolidation, and suspension to optimize coastal Louisiana restoration

Science.gov (United States)

Sha, X.; Xu, K.; Bentley, S. J.; Robichaux, P. A.

2018-04-01

Many research efforts have been undertaken over many decades in the field of Louisiana coastal restoration, but long-term experiments for sediment suspension and consolidation in diversion-receiving basins are still limited, despite significance of this topic to ongoing restoration strategies. Sediment samples were collected from two active diversions on the Mississippi River: West Bay, a semi-enclosed bay located on the Mississippi River Delta and fed by the West Bay Diversion, and from Big Mar pond, a receiving basin of the Caernarvon freshwater diversion from the lower Mississippi River, Louisiana, USA. A dual-core Gust Erosion Microcosm System was used to measure time-series (0.5, 1, 2, 3, 4, 5, and 6-months after initial settling) erodibility at seven shear stress regimes (0.01-0.60 Pa) using experimental cores prepared with two initial sediment concentrations (60 and 120 kg m-3). A 230-cm tall settling column with nine sampling ports was used to measure the consolidation rates for initial sediment concentrations ranging from fluid mud (10 kg m-3) to dredge effluent (120 kg m-3), in combination with two levels of salinity (1 and 5). The erodibility of West Bay sediment decreased with increasing time of consolidation. The critical shear stress for resuspension increased from 0.2 Pa after 2 months to 0.45 Pa after 4 months of consolidation. The consolidation rates were inversely and exponentially related to initial sediment concentrations. Consolidation tests in salinity of 1 generally settled faster than that in salinity of 5, and consolidation tests with low sediment concentration tests generally settled faster than high-concentration tests. An exponential coefficient was added in the Sanford (2008) model to better predict the consolidation profile of both rapid early settling and slow self-weight consolidation processes. Our study suggests that enclosed basin, low salinity, relatively low sediment concentration and minimized disturbance for 4 months all favor

Numerical Modelling of Flow and Settling in Secondary Settling Tanks

DEFF Research Database (Denmark)

Dahl, Claus Poulsen

This thesis discusses the development of a numerical model for the simulation of secondary settling tanks. In the first part, the status on the development of numerical models for settling tanks and a discussion of the current design practice are presented. A study of the existing numerical models...... and design practice proved a demand for further development to include numerical models in the design of settling tanks, thus improving the future settling tanks....

Regional Operations Research Program for Commercialization of Geothermal Energy in the Rocky Mountain Basin and Range. Final Technical Report, January 1980--March 1981

Energy Technology Data Exchange (ETDEWEB)

None

1981-07-01

This report describes the work accomplished from January 1980 to March 1981 in the Regional Operations Research efforts for the Rocky Mountain Basin and Range Geothermal Commercialization Program. The scope of work is as described in New Mexico State University Proposal 80-20-207. The work included continued data acquisition and extension of the data base, enhancement and refinement of the economic models for electric and direct use applications, site-specific and aggregated analyses in support of the state teams, special analyses in support of several federal agencies, and marketing assistance to the state commercialization teams.

Multi-variable evaluation of hydrological model predictions for a headwater basin in the Canadian Rocky Mountains

Directory of Open Access Journals (Sweden)

X. Fang

2013-04-01

Full Text Available One of the purposes of the Cold Regions Hydrological Modelling platform (CRHM is to diagnose inadequacies in the understanding of the hydrological cycle and its simulation. A physically based hydrological model including a full suite of snow and cold regions hydrology processes as well as warm season, hillslope and groundwater hydrology was developed in CRHM for application in the Marmot Creek Research Basin (~ 9.4 km2, located in the Front Ranges of the Canadian Rocky Mountains. Parameters were selected from digital elevation model, forest, soil, and geological maps, and from the results of many cold regions hydrology studies in the region and elsewhere. Non-calibrated simulations were conducted for six hydrological years during the period 2005–2011 and were compared with detailed field observations of several hydrological cycle components. The results showed good model performance for snow accumulation and snowmelt compared to the field observations for four seasons during the period 2007–2011, with a small bias and normalised root mean square difference (NRMSD ranging from 40 to 42% for the subalpine conifer forests and from 31 to 67% for the alpine tundra and treeline larch forest environments. Overestimation or underestimation of the peak SWE ranged from 1.6 to 29%. Simulations matched well with the observed unfrozen moisture fluctuation in the top soil layer at a lodgepole pine site during the period 2006–2011, with a NRMSD ranging from 17 to 39%, but with consistent overestimation of 7 to 34%. Evaluations of seasonal streamflow during the period 2006–2011 revealed that the model generally predicted well compared to observations at the basin scale, with a NRMSD of 60% and small model bias (1%, while at the sub-basin scale NRMSDs were larger, ranging from 72 to 76%, though overestimation or underestimation for the cumulative seasonal discharge was within 29%. Timing of discharge was better predicted at the Marmot Creek basin outlet

Treatment of spent nuclear fuel L-basin sludge

International Nuclear Information System (INIS)

Westover, B.L.; Oji, L.N.; Martin, H.L.; Nichols, D.M.

1997-01-01

Each production reactor at the DOE Savannah River Site (SRS) has a disassembly basin whose primary purpose is to cool irradiated production fuel and target. The disassembly basins also provide a shielded environment for personnel. Material has historically resided in the basins for 6 to 12 months. Increases in basin storage time have occurred, and have caused the buildup of a sludge layer on the basin floors to be greater than historical levels. The sludge is composed primarily of inorganic oxide and hydroxide corrosion products. The sludge layer has increased the turbidity and conductivity of the basin water, contributed to fuel corrosion, and has impacted fuel handling operations. Initial characterization of the sludge indicates that it is a low-level radioactive aqueous waste. This evaluation looked at methods to separate the sludge into its liquid and solid phases. The experimental data obtained during this evaluation clearly shows that a filtration-based approach to dewatering using an Oberlin pressure filtration unit at SRS is possible. This research task was to identify and optimize filtration and settling parameters pursuant sludge processing. The research specifically addressed: choice of filter aid, filter aid to sludge ratio, choice and dosage of polymer flocculation and settling agents, and the determination of Kynch curve settling parameters. Two commercial perlite filter-aids were identified as the most suitable. Of 11 water soluble flocculating polymers evaluated, 3 cationic commercial types formed stable flocs in the screening tests. In low doses, the flocculating polymers also enhanced sludge particle settling and decreased filtrate turbidity. The filtration cake from the sludge can be solidified to meet waste acceptance and storage criteria. However, the conductivity of the remaining filtrate does not meet Reactor Area Return Water criteria and may require a secondary filtration process. 2 refs., 14 figs., 5 tabs

Mapping critical loads of nitrogen deposition for aquatic ecosystems in the Rocky Mountains, USA

Science.gov (United States)

Nanus, Leora; Clow, David W.; Saros, Jasmine E.; Stephens, Verlin C.; Campbell, Donald H.

2012-01-01

Spatially explicit estimates of critical loads of nitrogen (N) deposition (CLNdep) for nutrient enrichment in aquatic ecosystems were developed for the Rocky Mountains, USA, using a geostatistical approach. The lowest CLNdep estimates (-1 yr-1) occurred in high-elevation basins with steep slopes, sparse vegetation, and abundance of exposed bedrock and talus. These areas often correspond with areas of high N deposition (>3 kg N ha-1 yr-1), resulting in CLNdep exceedances ≥1.5 ± 1 kg N ha-1 yr-1. CLNdep and CLNdep exceedances exhibit substantial spatial variability related to basin characteristics and are highly sensitive to the NO3- threshold at which ecological effects are thought to occur. Based on an NO3- threshold of 0.5 μmol L-1, N deposition exceeds CLNdep in 21 ± 8% of the study area; thus, broad areas of the Rocky Mountains may be impacted by excess N deposition, with greatest impacts at high elevations.

Climate vulnerability of native cold-water salmonids in the Northern Rockies Region [Chapter 5

Science.gov (United States)

Michael K. Young; Daniel J. Isaak; Scott Spaulding; Cameron A. Thomas; Scott A. Barndt; Matthew C. Groce; Dona Horan; David E. Nagel

2018-01-01

During the 21st century, climate change is expected to alter aquatic habitats throughout the Northern Rocky Mountains, intermountain basins, and western Great Plains. Particularly in montane watersheds, direct changes are likely to include warmer water temperatures, earlier snowmelt-driven runoff, earlier declines to summer baseflow, downhill movement of perennial...

A Novel Model for the Entire Settling-Thickening Process in a Secondary Settling Tank.

Science.gov (United States)

He, Zhijiang; Zhang, Yuankai; Wang, Hongchen; Qi, Lu; Yin, Xunfei; Zhang, Xiaojun; Wen, Yang

2016-12-01

  Sludge settling and thickening occur simultaneously in secondary settling tanks (SSTs). The ability to accurately calculate the settling and thickening capacity of activated sludge was of great importance. Despite extensive studies on the development of settling velocity models for use with SSTs, these models have not been applied due to the difficulty in calibrating the related parameters. Additionally, there have been some studies of the thickening behavior of the activated sludge in SSTs. In this study, a novel settling and thickening model for activated sludge was developed, and the model was validated using experimental data (R2 = 0.830 to 0.963, p settling and thickening behavior of the activated sludge in an SST. The application of these models requires only one critical parameter, namely, the stirred sludge volume index SSVI3.5, which is readily available in a water resource recovery facility.

Are rocky shore ecosystems affected by nutrient-enriched seawater? Some preliminary results from a mesocosm experiment

NARCIS (Netherlands)

Bokn, T.L.; Moy, F.E.; Christie, H.; Engelbert, S.; Karez, R.; Kersting, K.; Kraufvelin, P.; Lindblad, C.; Marba, N.; Pedersen, M.F.; Sorensen, K.

2002-01-01

The response of rocky shore ecosystems to increased nutrient availability was examined in eight land-based mesocosms designed for hard-bottom littoral communities built at Marine Research Station Solbergstrand (Norway). The average seawater volume in each basin was 9 m3 with an average water

Numerical Modeling of Large-Scale Rocky Coastline Evolution

Science.gov (United States)

Limber, P.; Murray, A. B.; Littlewood, R.; Valvo, L.

2008-12-01

, increases weathering and erosion around the headland, and eventually changes the headland into an embayment! Improvements to our modeling approach include refining the initial conditions. To create a fractal, immature rocky coastline, self-similar river networks with random side branches were drawn on the shoreline domain. River networks and side branches were scaled according to Horton's law and Tokunaga statistics, respectively, and each river pathway was assigned a simple exponential longitudinal profile. Topography was generated around the river networks to create drainage basins and, on a larger scale, represent a mountainous, fluvially-sculpted landscape. The resultant morphology was then flooded to a given elevation, leaving a fractal rocky coastline. In addition to the simulated terrain, actual digital elevation models will also be used to derive the initial conditions. Elevation data from different mountainous geomorphic settings such as the decaying Appalachian Mountains or actively uplifting Sierra Nevada can be effectively flooded to a given sea level, resulting in a fractal and immature coastline that can be input to the numerical model. This approach will offer insight into how rocky coastlines in different geomorphic settings evolve, and provide a useful complement to results using the simulated terrain.

Contingency table analysis of pebble lithology and roundness: A case study of Huangshui River, China and comparison to rivers in the Rocky Mountains, USA

Science.gov (United States)

Miao, X.; Lindsey, D.A.; Lai, Z.; Liu, Xiuying

2010-01-01

Contingency table analysis of pebble lithology and roundness is an effective way to identify the source terrane of a drainage basin and to distinguish changes in basin size, piracy, tectonism, and other events. First, the analysis to terrace gravel deposited by the Huangshui River, northeastern Tibet Plateau, China, shows statistically contrasting pebble populations for the oldest terrace (T7, Dadongling, 1.2. Ma) and the youngest terraces (T0-T3, ?. 0.15. Ma). Two fluvial processes are considered to explain the contrast in correlation between lithology and roundness in T7 gravel versus T0-T3 gravel: 1) reworking of T7 gravel into T0-T3 gravel and 2) growth in the size of the river basin between T7 and T0-T3 times. We favor growth in basin size as the dominant process, from comparison of pebble counts and contingency tables. Second, comparison of results from Huangshui River of China to three piedmont streams of the Rocky Mountains, USA highlights major differences in source terrane and history. Like Rocky Mountain piedmont gravel from Colorado examples, the Huangshui gravels show a preference (observed versus expected frequency) for rounded granite. But unlike Rocky Mountain gravel, Huangshui gravel shows a preference for angular quartzite and for rounded sandstone. In conclusion, contrasting behavior of lithologies during transport, not always apparent in raw pebble counts, is readily analyzed using contingency tables to identify the provenance of individual lithologies, including recycled clasts. Results of the analysis may help unravel river history, including changes in basin size and lithology. ?? 2009.

Contrast settling in cerebral aneurysm angiography

International Nuclear Information System (INIS)

Wang Zhijie; Hoffmann, Kenneth R; Guterman, Lee R; Wang Zhou; Rudin, Stephen; Meng Hui

2005-01-01

During angiography, blood flow is visualized with a radiopaque contrast agent, which is denser than blood. In complex vasculature, such as cerebral saccular aneurysms, the density difference may produce an appreciable gravity effect, where the contrast material separates from blood and settles along the gravity direction. Although contrast settling has been occasionally reported before, the fluid mechanics behind it have not been explored. Furthermore, the severity of contrast settling in cerebral aneurysms varies significantly from case to case. Therefore, a better understanding of the physical principles behind this phenomenon is needed to evaluate contrast settling in clinical angiography. In this study, flow in two identical groups of sidewall aneurysm models with varying parent-vessel curvature was examined by angiography. Intravascular stents were deployed into one group of the models. To detect contrast settling, we used lateral view angiography. Time-intensity curves were analysed from the angiographic data, and a computational fluid dynamic analysis was conducted. Results showed that contrast settling was strongly related to the local flow dynamics. We used the Froude number, a ratio of flow inertia to gravity force, to characterize the significance of gravity force. An aneurysm with a larger vessel curvature experienced higher flow, which resulted in a larger Froude number and, thus, less gravitational settling. Addition of a stent reduced the aneurysmal flow, thereby increasing the contrast settling. We found that contrast settling resulted in an elevated washout tail in the time-intensity curve. However, this signature is not unique to contrast settling. To determine whether contrast settling is present, a lateral view should be obtained in addition to the anteroposterior (AP) view routinely used clinically so as to rule out contrast settling and hence to enable a valid time-intensity curve analysis of blood flow in the aneurysm

Native plant development and restoration program for the Great Basin, USA

Science.gov (United States)

N. L. Shaw; M. Pellant; P. Olweli; S. L. Jensen; E. D. McArthur

2008-01-01

The Great Basin Native Plant Selection and Increase Project, organized by the USDA Bureau of Land Management, Great Basin Restoration Initiative and the USDA Forest Service, Rocky Mountain Research Station in 2000 as a multi-agency collaborative program (http://www.fs.fed.us/rm/boise/research/shrub/greatbasin.shtml), has the objective of improving the availability of...

A Combined Raindrop Aggregate Destruction Test-Settling Tube (RADT-ST Approach to Identify the Settling Velocity of Sediment

Directory of Open Access Journals (Sweden)

Liangang Xiao

2015-10-01

Full Text Available The use of sediment settling velocity based on mineral grain size distribution in erosion models ignores the effects of aggregation on settling velocity. The alternative approach, wet-sieved aggregate size distribution, on the other hand, cannot represent all destructive processes that eroded soils may experience under impacting raindrops. Therefore, without considering raindrop impact, both methods may lead to biased predictions of the redistribution of sediment and associated substances across landscapes. Rainfall simulation is an effective way to simulate natural raindrop impact under controlled laboratory conditions. However, very few methods have been developed to integrate rainfall simulation with the settling velocity of eroded sediment. This study aims to develop a new proxy, based on rainfall simulation, in order to identify the actual settling velocity distribution of aggregated sediment. A combined Raindrop Aggregate Destruction Test-Settling Tube (RADT-ST approach was developed to (1 simulate aggregate destruction under a series of simulated rainfalls; and (2 measure the actual settling velocity distribution of destroyed aggregates. Mean Weight Settling Velocity (MWSV of aggregates was used to investigate settling behaviors of different soils as rainfall kinetic energy increased. The results show the settling velocity of silt-rich raindrop impacted aggregates is likely to be underestimated by at least six times if based on mineral grain size distribution. The RADT-ST designed in this study effectively captures the effects of aggregation on settling behavior. The settling velocity distribution should be regarded as an evolving, rather than steady state parameter during erosion events. The combined RADT-ST approach is able to generate the quasi-natural sediment under controlled simulated rainfall conditions and is adequately sensitive to measure actual settling velocities of differently aggregated soils. This combined approach provides

Great Basin Research and Management Project: Restoring and maintaining riparian ecosystem integrity

Science.gov (United States)

Jeanne C. Chambers

2000-01-01

The Great Basin Research and Management Project was initiated in 1994 by the USDA Forest Service, Rocky Mountain Research Station’s Ecology, Paleoecology, and Restoration of Great Basin Watersheds Project to address the problems of stream incision and riparian ecosystem degradation in central Nevada. It is a highly interdisciplinary project that is being conducted in...

Sedimentation process and design of settling systems

CERN Document Server

De, Alak

2017-01-01

This book is designed to serve as a comprehensive source of information of sedimentation processes and design of settling systems, especially as applied to design of such systems in civil and environmental engineering. The book begins with an introduction to sedimentation as a whole and goes on to cover the development and details of various settling theories. The book traces the chronological developments of the comprehensive knowledge of settling studies and design of settling systems from 1889.A new concept of 'Velocity Profile Theorem', tool for settling problem analysis, has been employed to the analysis of the phenomenon of short circuiting. Complete theory of tube settling has been developed and its application to the computation of residual solids from the assorted solids through the same has been demonstrated. Experimental verification of the tube settling theory has also been presented. Field-oriented compatible design and operation methodology of settling system has been developed from the detailed...

Characterization of uranium in surface-waters collected at the Rocky Flats Facility

International Nuclear Information System (INIS)

Efurd, D.W.; Rokop, D.J.; Aguilar, R.D.; Roensch, F.R.; Perrin, R.E.; Banar, J.C.

1994-01-01

The Rocky Flats Plant (RFP) is a Department of Energy (DOE) facility where plutonium and uranium components were manufactured for nuclear weapons. During plant operations radioactivity was inadvertently released into the environment. This study was initiated to characterize the uranium present in surface-waters at RFP. Three drainage basins and natural ephemeral streams transverse RFP. The Woman Creek drainage basin traverses and drains the southern portion of the site. The Rock Creek drainage basin drains the northwestern portion of the plant complex. The Walnut Creek drainage basin traverses the western, northern, and northeastern portions of the RFP site. Dams, detention ponds, diversion structures, and ditches have been constructed at RFP to control the release of plant discharges and surface (storm water) runoff. The ponds located downstream of the plant complex on North Walnut Creek are designated A-1 through A-4. Ponds on South Walnut Creek are designated B-1 through B-5. The ponds in the Woman Creek drainage basin are designated C-1 and C-2. Water samples were collected from each pond and the uranium was characterized by TIMS measurement techniques

M-area basin closure-Savannah River Site

International Nuclear Information System (INIS)

McMullin, S.R.; Horvath, J.G.

1991-01-01

M-Area, on the Savannah River Site, processes raw materials and manufactures fuel and target rods for reactor use. Effluent from these processes were discharged into the M-Area settling basin and Lost Lake, a natural wetland. The closure of this basin began in 1988 and included the removal and stabilization of basin fluids, excavation of all contaminated soils from affected areas and Lost Lake, and placement of all materials in the bottom of the emptied basin. These materials were covered with a RCRA style cap, employing redundant barriers of kaolin clay and geosynthetic material. Restoration of excavated uplands and wetlands is currently underway

Settling and sedimentation behavior of fine-grained materials

OpenAIRE

Nam, Sookie

2005-01-01

Channeling has already been an observed phenomenon that often occurs during settling and sedimentation processes of finer materials. However, it has been regarded as a minor factor affecting settling process, e.g. settling velocity or consolidation rate. In this study, settling behaviors of talcs, kaolins and attapulgite were reviewed by experiments with small and large settling columns with special focus on channel formation during sedimentation. The large settling column is equipped with tw...

Rocky Mountain spotted fever

Science.gov (United States)

... spotted fever on the foot Rocky Mountain spotted fever, petechial rash Antibodies Deer and dog tick References McElligott SC, Kihiczak GG, Schwartz RA. Rocky Mountain spotted fever and other rickettsial infections. In: Lebwohl MG, Heymann ...

Removal of Heavy Metals and PAH in Retention Basins

DEFF Research Database (Denmark)

Larsen, Torben; Neerup-Jensen, Ole

2004-01-01

Solid seperation in retention basins is strongly non-linear and depends significantly on the flow rate and the settling characteristics of the particles. Accordingly the calculation of the annual loads of pollutants from storm overflows including basins is rather complex and time consuming...... in order to calculate annual loads of pollutants from urban catchments. The study cover Cd, Cu, Ni, Pb, Zn and PAH....

Rocky Mountain Spotted Fever

Science.gov (United States)

... with facebook share with twitter share with linkedin Rocky Mountain Spotted Fever Credit: CDC A male cayenne tick, Amblyomma cajennense, ... and New Mexico. Why Is the Study of Rocky Mountain Spotted Fever a Priority for NIAID? Tickborne diseases are becoming ...

Nitrogen isotope compositions and spatial distribution characteristics of soil in the process of karst rocky desertification

International Nuclear Information System (INIS)

Luo Xuqiang; Wang Shijie; Wang Chengyuan; Liang Yuhua; Liao Xinrong; Yang Hongyan

2011-01-01

Isotopic composition and spatial distribution characteristic of total nitrogen of the surficial soil in karst rocky desertification area, including different types, different grades and different disturbed modes karst rocky desertification within the same small catchment, which belong to the Wangjiazhai peak-cluster depression basin and located in Qingzhen City, Guizhou Province were discussed in this study. Results showed that δ 15 N values of total nitrogen in top soil in yellow soil area were mainly between +0.35‰ ∼ +6.82% with the average of +4.50‰, and between +2.70‰ ∼ +6.50‰ in black calcareous with the average of +4.27‰. In both yellow soil area and black calcareous area, there were no significant difference in the δ 15 N values of total nitrogen on sample lands of rocky desertification at different levels, different ways of interruption and different slope positions, and no obvious difference on the whole (P≤0.05), which is mainly due to the high habitat heterogeneity of karst area. (authors)

Simulation of sediment settling in reduced gravity

Science.gov (United States)

Kuhn, Nikolaus; Kuhn, Brigitte; Rüegg, Hans-Rudolf; Gartmann, Andres

2015-04-01

Gravity has a non-linear effect on the settling velocity of sediment particles in liquids and gases due to the interdependence of settling velocity, drag and friction. However, Stokes' Law or similar empirical models, the common way of estimating the terminal velocity of a particle settling in a gas or liquid, carry the notion of a drag as a property of a particle, rather than a force generated by the flow around the particle. For terrestrial applications, this simplifying assumption is not relevant, but it may strongly influence the terminal velocity achieved by settling particles on other planetary bodies. False estimates of these settling velocities will, in turn, affect the interpretation of particle sizes observed in sedimentary rocks, e.g. on Mars and the search for traces of life. Simulating sediment settling velocities on other planets based on a numeric simulation using Navier-Stokes equations and Computational Fluid Dynamics requires a prohibitive amount of time and lacks measurements to test the quality of the results. The aim of the experiments presented in this study was therefore to quantify the error incurred by using settling velocity models calibrated on Earth at reduced gravities, such as those on the Moon and Mars. In principle, the effect of lower gravity on settling velocity can be achieved by reducing the difference in density between particle and liquid. However, the use of such analogues creates other problems because the properties (i.e. viscosity) and interaction of the liquids and sediment (i.e. flow around the boundary layer between liquid and particle) differ from those of water and mineral particles. An alternative for measuring the actual settling velocities of particles under reduced gravity, on Earth, is offered by placing a settling tube on a reduced gravity flight and conduct settling velocity measurements within the 20 to 25 seconds of Martian gravity that can be simulated during such a flight. In this presentation, the results

Flocculent Settling of Food Wastes.

Science.gov (United States)

Chowdhury, Mohammad Monirul Islam; Kim, Mingu; Haroun, Basem Mikhaeil; Nakhla, George; Keleman, Michael

2016-07-01

This study evaluated the flocculent settling in water and municipal wastewater (MWW) in a 10.6 ft deep column. A total of eight runs at three different testing conditions involving MWW alone, food waste (FW) alone, and FW in MWW (FW+MWW) were conducted. Total suspended solid (TSS), total BOD (TBOD), total COD (TCOD), total nitrogen (TN), and total phosphorous (TP) removal efficiencies after 3 hours of settling were 62%, 46%, 49%, 46% and 62% for FW, and 50%, 43%, 39%, 37% and 24% for MWW. Removal efficiencies of particulate COD (PCOD) and particulate BOD (PBOD) at the lowest surface overflow rate (SOR) of 1.1 m3/m2/hr corresponding to the longest settling time of 3 hours were 59% and 64% for FW, and 65% and 70% for FW with MWW samples. On the other hand, no significant variation between FW and FW with MWW was observed for PN removal after 3 hours of settling.

Long-range Rocky Flats utilization study

International Nuclear Information System (INIS)

1983-02-01

The purpose of this Study was to provide information concerning the Rocky Flats Plant and its operations that will be useful to the Nation's decision-makers in determining the long-range future of the Plant. This Study was conducted under the premise that national defense policy must be supported and, accordingly, the capabilities at Rocky Flats must be maintained there or at some other location(s). The Study, therefore, makes no attempt to speculate on how possible future changes in national defense policy might affect decisions regarding the utilization of Rocky Flats. Factors pertinent to decisions regarding Rocky Flats, which are included in the Study, are: physical condition of the Plant and its vulnerabilities to natural phenomena; risks associated with plutonium to Plant workers and the public posed by postulated natural phenomena and operational accidents; identification of alternative actions regarding the future use of the Rocky Flats Plant with associated costs and time scales; local socioeconomic impacts if Rocky Flats operations were relocated; and potential for other uses if Rocky Flats facilities were vacated. The results of the tasks performed in support of this Study are summarized in the context of these five factors

System Description for the KW Basin Integrated Water Treatment System (IWTS) (70.3)

International Nuclear Information System (INIS)

DERUSSEAU, R.R.

2000-01-01

This is a description of the system that collects and processes the sludge and radioactive ions released by the spent nuclear fuel (SNF) processing operations conducted in the 105 KW Basin. The system screens, settles, filters, and conditions the basin water for reuse. Sludge and most radioactive ions are removed before the water is distributed back to the basin pool. This system is part of the Spent Nuclear Fuel Project (SNFP)

What is 'settled Science'?

Science.gov (United States)

Brown, M.

2013-12-01

Republican strategist Frank Luntz famously advised party leaders to emphasize the lack of ';scientific certainty' about global warming because, once the public became convinced of a scientific consensus on global warming, they would accept it and policies responding to it. But philosophical work on scientific methodology puts absolute certainty out of reach. Today almost all philosophers are fallibilists, holding that every belief is subject to correction. Does it follow that an honest report of what science has to say about any topic cannot claim that the matter is settled? I defend a more confident view: much of what science has to say about the world is settled. On this view, settled science doesn't require philosophical certainty. Instead, it is based on stable agreement and practical reliability--values central to C.S. Peirce's account of the scientific method. Defending this position requires care over changes in theory that can undermine the language in which these settled points were initially expressed. It also requires epistemic modesty, since our confidence in any claim, including observational claims, depends on a kind of induction, and could, in principle, be undermined. Interestingly, this line of thought also suggests many of the central claims the historical sciences make about our world are more stable and reliable than the more theory-dependent claims we think of as central to the foundations of physics. David Hume undermined philosophical certainty about causal laws when he argued that, no matter how many times we make observations confirming a law, it could still fail the next test. This point is sometimes confused with healthy scientific skepticism, but Hume's worry has a much broader scope than scientific skepticism. For Hume each instance of a causal relation was doubtful, no matter how similar to previous instances. But scientists are diffident about applying a well-tested law only when the circumstances differ. For instance, particle

System and technique for ultrasonic characterization of settling suspensions

Energy Technology Data Exchange (ETDEWEB)

Greenwood, Margaret S [Richland, WA; Panetta, Paul D [Richland, WA; Bamberger, Judith A [Richland, WA; Pappas, Richard A [Richland, WA

2006-11-28

A system for determining properties of settling suspensions includes a settling container, a mixer, and devices for ultrasonic interrogation transverse to the settling direction. A computer system controls operation of the mixer and the interrogation devices and records the response to the interrogating as a function of settling time, which is then used to determine suspension properties. Attenuation versus settling time for dilute suspensions, such as dilute wood pulp suspension, exhibits a peak at different settling times for suspensions having different properties, and the location of this peak is used as one mechanism for characterizing suspensions. Alternatively or in addition, a plurality of ultrasound receivers are arranged at different angles to a common transmitter to receive scattering responses at a variety of angles during particle settling. Angular differences in scattering as a function of settling time are also used to characterize the suspension.

Measuring water and sediment discharge from a road plot with a settling basin and tipping bucket

Science.gov (United States)

Thomas A. Black; Charles H. Luce

2013-01-01

A simple empirical method quantifies water and sediment production from a forest road surface, and is well suited for calibration and validation of road sediment models. To apply this quantitative method, the hydrologic technician installs bordered plots on existing typical road segments and measures coarse sediment production in a settling tank. When a tipping bucket...

Rocky Flats Compliance Program

International Nuclear Information System (INIS)

1994-02-01

The Department of Energy (DOE) established the Office of Technology Development (EM-50) (OTD) as an element of Environmental Restoration and Waste Management (EM) in November 1989. The primary objective of the Office of Technology Development, Rocky Flats Compliance Program (RFCP), is to develop altemative treatment technologies for mixed low-level waste (wastes containing both hazardous and radioactive components) to use in bringing the Rocky Flats Plant (RFP) into compliance with Federal and state regulations and agreements. Approximately 48,000 cubic feet of untreated low-level mixed waste, for which treatment has not been specified, are stored at the RFP. The cleanup of the Rocky Flats site is driven by agreements between DOE, the Environmental Protection Agency (EPA), and the Colorado Department of Health (CDH). Under these agreements, a Comprehensive Treatment and Management Plan (CTMP) was drafted to outline the mechanisms by which RFP will achieve compliance with the regulations and agreements. This document describes DOE's strategy to treat low-level mixed waste to meet Land Disposal Restrictions and sets specific milestones related to the regulatory aspects of technology development. These milestones detail schedules for the development of technologies to treat all of the mixed wastes at the RFP. Under the Federal Facilities Compliance Act (FFCA), the CTMP has been incorporated into Rocky Flats Plant Conceptual Site Treatment Plan (CSTP). The CSTP will become the Rocky Flats Plant site Treatment Plan in 1995 and will supersede the CTMP

Particle Settling in Low Energy Turbulence

Science.gov (United States)

Allen, Rachel; MacVean, Lissa; Tse, Ian; Mazzaro, Laura; Stacey, Mark; Variano, Evan

2014-11-01

Particle settling velocities can be altered by turbulence. In turbulence, dense particles may get trapped in convergent flow regions, and falling particles may be swept towards the downward side of turbulent eddies, resulting in enhanced settling velocities. The degree of velocity enhancement may depend on the Stokes number, the Rouse number, and the turbulent Reynolds number. In a homogeneous, isotropic turbulence tank, we tested the effects of particle size and type, suspended sediment concentration, and level of turbulence on the settling velocities of particles typically found in muddy estuaries. Two Acoustic Doppler Velocimeters (ADVs), separated vertically, measured turbulent velocities and suspended sediment concentrations, which yield condition dependent settling velocities, via ∂/á C ñ ∂ t = -∂/∂ z (ws á C ñ + á w ' C ' ñ) . These results are pertinent to fine sediment transport in estuaries, where high concentrations of suspended material are transported and impacted by low energy turbulence.

Geographic, geologic, and hydrologic summaries of intermontane basins of the northern Rocky Mountains, Montana

Science.gov (United States)

Kendy, Eloise; Tresch, R.E.

1996-01-01

This report combines a literature review with new information to provide summaries of the geography, geology, and hydrology of each of 32 intermontane basins in western Montana. The summary of each intermontane basin includes concise descriptions of topography, areal extent, altitude, climate, 1990 population, land and water use, geology, surface water, aquifer hydraulic characteristics, ground-water flow, and ground-water quality. If present, geothermal features are described. Average annual and monthly temperature and precipitation are reported from one National Weather Service station in each basin. Streamflow data, including the drainage area, period of record, and average, minimum, and maximum historical streamflow, are reported for all active and discontinued USGS streamflow-gaging stations in each basin. Monitoring-well data, including the well depth, aquifer, period of record, and minimum and maximum historical water levels, are reported for all long-term USGS monitoring wells in each basin. Brief descriptions of geologic, geophysical, and potentiometric- surface maps available for each basin also are included. The summary for each basin also includes a bibliography of hydrogeologic literature. When used alone or in conjunction with regional RASA reports, this report provides a practical starting point for site-specific hydrogeologic investigations.

Hydrology of area 52, Rocky Mountain coal province Wyoming, Colorado, Idaho, and Utah

Science.gov (United States)

Lowham, H.W.; Peterson, D.A.; Larson, L.R.; Zimmerman, E.A.; Ringen, B.H.; Mora, K.L.

1985-01-01

This report is one of a series designed to characterize the hydrology of drainage basins within coal provinces, nationwide. Area 52 (in the Rocky Mountain Coal Province) includes the Green River Basin upstream from the Yampa River, and the Bear River upstream from the Bear Lake - a total of 23,870 sq mi. Area 52 contains over 3 billion tons of strippable coal, most of which is located in the arid and semiarid plains. The report represents a summary of results of the water resources investigations of the U.S. Geological Survey, carried out in cooperation with State and other Federal agencies. More than 40 individual topics are discussed in a brief text that is accompanied by maps, graphs, photographs, and other illustrations. Primary topics in the report are: general features, resources and economy, surface-water quantity and quality, and groundwater. (USGS)

Middle Rockies Ecoregion: Chapter 5 in Status and trends of land change in the Western United States--1973 to 2000

Science.gov (United States)

Taylor, Janis L.

2012-01-01

The Middle Rockies Ecoregion—characterized by steep, high-elevation mountain ranges and intermountain valleys—is a disjunct ecoregion composed of three distinct geographic areas: the Greater Yellowstone area in northwest Wyoming, southwest Montana, and eastern Idaho; the Bighorn Mountains in north-central Wyoming and south-central Montana; and the Black Hills in western South Dakota and eastern Wyoming (Omernik, 1987; U.S. Environmental Protection Agency, 1997). The ecoregion covers approximately 90,160 km2 (34,881 mi2), and its three distinct geographic sections are bordered by several other ecoregions (fig. 1). The Yellowstone section abuts the Montana Valley and Foothill Prairies and the Northern Rockies Ecoregions to the north, the Snake River Basin and the Central Basin and Range Ecoregions to the west, and the Wyoming Basin Ecoregion to the south and east. The Bighorn Mountains section lies between the Wyoming Basin Ecoregion to the west and the Northwestern Great Plains Ecoregion to the east, and it abuts the Montana Valleys and Foothill Prairies Ecoregion to the north. The Black Hills section is entirely surrounded by the Northwestern Great Plains Ecoregion. The Continental Divide crosses the ecoregion from the southeast along the Wind River Range, through Yellowstone National Park, and west along the Montana-Idaho border. On both sides of the divide, topographic relief causes local climate variability, particularly the effects of aspect, exposure to prevailing wind, thermal inversions, and rain-shadow effects, that are reflected in the wide variety of flora and fauna within the ecoregion (Ricketts and others, 1999).

RESERVES IN WESTERN BASINS PART IV: WIND RIVER BASIN

Energy Technology Data Exchange (ETDEWEB)

Robert Caldwell

1998-04-01

Vast quantities of natural gas are entrapped within various tight formations in the Rocky Mountain area. This report seeks to quantify what proportion of that resource can be considered recoverable under today's technological and economic conditions and discusses factors controlling recovery. The ultimate goal of this project is to encourage development of tight gas reserves by industry through reducing the technical and economic risks of locating, drilling and completing commercial tight gas wells. This report is the fourth in a series and focuses on the Wind River Basin located in west central Wyoming. The first three reports presented analyses of the tight gas reserves and resources in the Greater Green River Basin (Scotia, 1993), Piceance Basin (Scotia, 1995) and the Uinta Basin (Scotia, 1995). Since each report is a stand-alone document, duplication of language will exist where common aspects are discussed. This study, and the previous three, describe basin-centered gas deposits (Masters, 1979) which contain vast quantities of natural gas entrapped in low permeability (tight), overpressured sandstones occupying a central basin location. Such deposits are generally continuous and are not conventionally trapped by a structural or stratigraphic seal. Rather, the tight character of the reservoirs prevents rapid migration of the gas, and where rates of gas generation exceed rates of escape, an overpressured basin-centered gas deposit results (Spencer, 1987). Since the temperature is a primary controlling factor for the onset and rate of gas generation, these deposits exist in the deeper, central parts of a basin where temperatures generally exceed 200 F and drill depths exceed 8,000 feet. The abbreviation OPT (overpressured tight) is used when referring to sandstone reservoirs that comprise the basin-centered gas deposit. Because the gas resources trapped in this setting are so large, they represent an important source of future gas supply, prompting studies

The Settling and Compaction of Nuclear Waste Slurries

International Nuclear Information System (INIS)

MACLEAN, G.T.

1999-01-01

The settling and compaction of simulated and real nuclear waste slurries were extensively studied. Experiments were carried out with simulated wastes at laboratory and large-scale sizes, and the results compared. A model of settling was derived and a method developed to correlate and scale-up settling data for different slurries and vessel sizes

Gravity settling of Hanford single-shell tank sludges

International Nuclear Information System (INIS)

Brooks, K.P.; Rector, D.R.; Smith, P.A.

1999-01-01

The US Department of Energy plans to use gravity settling in million-gallon storage tanks while pretreating sludge on the Hanford site. To be considered viable in these large tanks, the supernatant must become clear, and the sludge must be concentrated in an acceptable time. These separations must occur over the wide range of conditions associated with sludge pretreatment. In the work reported here, gravity settling was studied with liter quantities of actual single-shell tank sludge from hanford Tank 241-C-107. Because of limited sludge availability, an approach was developed using the results of these liter-scale tests to predict full-scale operation. Samples were centrifuged at various g-forces to simulate compaction with higher layers of sludge. A semi-empirical settling model was then developed incorporating both the liter-scale settling data and the centrifuge compression results to describe the sludge behavior in a million-gallon tank. The settling model predicted that the compacted sludge solids would exceed 20 wt% in less than 30 days of settling in a 10-m-tall tank for all pretreatment steps

A new settling velocity model to describe secondary sedimentation

DEFF Research Database (Denmark)

Ramin, Elham; Wágner, Dorottya Sarolta; Yde, Lars

2014-01-01

Secondary settling tanks (SSTs) are the most hydraulically sensitive unit operations in biological wastewater treatment plants. The maximum permissible inflow to the plant depends on the efficiency of SSTs in separating and thickening the activated sludge. The flow conditions and solids...... distribution in SSTs can be predicted using computational fluid dynamics (CFD) tools. Despite extensive studies on the compression settling behaviour of activated sludge and the development of advanced settling velocity models for use in SST simulations, these models are not often used, due to the challenges...... associated with their calibration. In this study, we developed a new settling velocity model, including hindered, transient and compression settling, and showed that it can be calibrated to data from a simple, novel settling column experimental set-up using the Bayesian optimization method DREAM...

Settling velocities in batch sedimentation

International Nuclear Information System (INIS)

Fricke, A.M.; Thompson, B.E.

1982-10-01

The sedimentation of mixtures containing one and two sizes of spherical particles (44 and 62 μm in diameter) was studied. Radioactive tracing with 57 Co was used to measure the settling velocities. The ratio of the settling velocity U of uniformly sized particles to the velocity predicted to Stokes' law U 0 was correlated to an expression of the form U/U 0 = epsilon/sup α/, where epsilon is the liquid volume fraction and α is an empirical constant, determined experimentally to be 4.85. No effect of viscosity on the ratio U/U 0 was observed as the viscosity of the liquid medium was varied from 1x10 -3 to 5x10 -3 Pa.s. The settling velocities of particles in a bimodal mixture were fit by the same correlation; the ratio U/U 0 was independent of the concentrations of different-sized particles

Quantification of controls on regional rockfall activity and talus deposition, Kananaskis, Canadian Rockies

Science.gov (United States)

Thapa, Prasamsa; Martin, Yvonne E.; Johnson, E. A.

2017-12-01

Rockfall is a significant geomorphic process in many mountainous regions that also poses a notable natural hazard risk. Most previous studies of rockfall erosion have investigated the mechanics and rates of local rockwall retreat and talus deposition, with only a few investigations of rockfall and/or associated talus considering larger spatial scales (i.e., drainage basin, mountain range). The purpose of the current research is to investigate the areal extent of rockfall-talus and controlling factors of its distribution over regional spatial scales (of order 102 km2) in Kananaskis, Canadian Rockies to inform our understanding of its significance in mountain development. To achieve this goal, a large talus inventory is collected and analyzed for 11 steep tributaries of the Kananaskis River, Canadian Rockies. Talus accumulations associated with rockfall provide evidence about the nature and rates of rockfall activity that supplies sediment to these deposits and are the focus of the present study. To quantify the controls of rockfall-talus activity in this region, we analyze the association of talus deposits with structural geology, glacial topography, and temperature-related weathering (i.e., frost cracking). A total of 324 talus polygons covering a surface area of 28.51 km2 are delineated within the 11 study basins, with the number of talus polygons in each study basin ranging from 1 to 73. Analysis of the talus inventory shows that cirques and glacially sculpted valleys are locations of notable talus accumulation in Kananaskis, with other locations of significant talus deposition being associated with thrust faults. We also found that the upper elevations at which talus deposits are typically found are the general range of elevations experiencing a notable number of days in the frost cracking window when this window is defined as - 3 to - 15 °C; no such association is found for the frost cracking window of - 3 to - 8 °C. Estimates of average erosion rates for all

Macrofauna on rocky substrates in the Forsmark biotest basin. March 1984 - March 1985

International Nuclear Information System (INIS)

Snoeijs, P.; Mo, K.

1987-09-01

The Forsmark biotest basin, situated on the Swedish east coast, is an artificial offshore brackish lake, through which the cooling water is channelled from the Forsmark nuclear power plant to the Bothnian Sea. The biotest basin is up to 10 0 C warmer than the sea surrounding it, and has no ice cover in winter. There is an artificial, fast current in a large part of the basin. Macrofauna on stones in the hydrolittoral belt was sampled at 11 sites in- and outside the basin every third week during one year. The numbers of individuals per m 2 for each taxon were counted. Diversity indices and dominance-diversity curves were computed for each site on the basis of pooled data for the cold season, and for the rest of the year. In total 66 taxa were distinguished in the species lists, of which 3 are sessile, the rest free-living. (orig./DG)

Assessment of Jet Erosion for Potential Post-Retrieval K-Basin Settled Sludge

Energy Technology Data Exchange (ETDEWEB)

Wells, Beric E.; Enderlin, Carl W.; Gauglitz, Phillip A.; Peterson, Reid A.

2009-09-29

Packaged K-Basin sludge will be transported to the T Plant on the Hanford Site where it will be interim stored. The sludge will be retrieved from the storage containers and processed for disposal. A sample of high uranium content canister sludge, designated 96-13, "self-cemented" during laboratory storage. This sample was uncharacteristically strong compared to expected K-Basin material. The purpose for this work is to evaluate the potential retrieval of such sludge after storage at the T Plant via jet erosion. The specific objectives of this report are to determine the modes of erosion and the methods used to measure/assess the erodibility parameters of sludge and identify those parameters applicable to jet erosion. The erodibility parameters of sample 96-13 are characterized to the extent possible. These objectives have been met based on literature review, past experience at Pacific Northwest National Laboratory, and observation of sample 96-13 video during hot-cell activities.

State geothermal commercialization programs in seven Rocky Mountain states. Semiannual progress report, January-July 1981

Energy Technology Data Exchange (ETDEWEB)

Lunis, B.C.; Toth, W.J. (comps.)

1982-05-01

The activities and findings of the seven state commercialization teams participating in the Rocky Mountain Basin and Range commercialization program are described. For each state (Colorado, Montana, New Mexico, North and South Dakota, Utah, and Wyoming), prospect identification, area development plans, site specific development analyses, time-phased project plans, the aggregated prospective geothermal energy use, and institutional analyses are discussed. Public outreach activities are also covered, and findings and recommendations are given for each state. Some background information about the program is provided. (LEW)

State geothermal commercialization programs in seven Rocky Mountain states. Semiannual progress report, July-December 1981

Energy Technology Data Exchange (ETDEWEB)

Lunis, B.C. (ed.)

1982-08-01

The activities and findings of the seven state commercialization teams participating in the Rocky Mountain Basin and Range commercialization program are described. The period covered is July through December 1981. Background information is provided, program objectives and the technical approach used are discussed, and the benefits of the program are described. Prospect identification, area development plans, site specific development analyses, time-phased project plans, the aggregated prospective geothermal energy use, and institutional analyses are discussed. Public outreach activities are covered and findings and recommendations are summarized.

State geothermal commercialization programs in ten Rocky Mountain states. Semi-annual progress report, July-December 1979

Energy Technology Data Exchange (ETDEWEB)

Griffith, J.L. (comp.)

1980-08-01

The activities and findings of the ten state teams participating in the Rocky Mountain Basin and Range Regional Hydrothermal Commercialization Program for the period are described. A summary of the state projects, compilation of project accomplishments, summary of findings, and a description of the major conclusions and recommendations are presented. Also included are chapters on the commercialization activities carried out by individual teams in each state: Arizona, Colorado, Idaho, Montana, Nevada, New-Mexico, North Dakota, South Dakota, Utah, and Wyoming. (MHR)

A new settling velocity model to describe secondary sedimentation.

Science.gov (United States)

Ramin, Elham; Wágner, Dorottya S; Yde, Lars; Binning, Philip J; Rasmussen, Michael R; Mikkelsen, Peter Steen; Plósz, Benedek Gy

2014-12-01

Secondary settling tanks (SSTs) are the most hydraulically sensitive unit operations in biological wastewater treatment plants. The maximum permissible inflow to the plant depends on the efficiency of SSTs in separating and thickening the activated sludge. The flow conditions and solids distribution in SSTs can be predicted using computational fluid dynamics (CFD) tools. Despite extensive studies on the compression settling behaviour of activated sludge and the development of advanced settling velocity models for use in SST simulations, these models are not often used, due to the challenges associated with their calibration. In this study, we developed a new settling velocity model, including hindered, transient and compression settling, and showed that it can be calibrated to data from a simple, novel settling column experimental set-up using the Bayesian optimization method DREAM(ZS). In addition, correlations between the Herschel-Bulkley rheological model parameters and sludge concentration were identified with data from batch rheological experiments. A 2-D axisymmetric CFD model of a circular SST containing the new settling velocity and rheological model was validated with full-scale measurements. Finally, it was shown that the representation of compression settling in the CFD model can significantly influence the prediction of sludge distribution in the SSTs under dry- and wet-weather flow conditions. Copyright © 2014 Elsevier Ltd. All rights reserved.

Symposium 9: Rocky Mountain futures: preserving, utilizing, and sustaining Rocky Mountain ecosystems

Science.gov (United States)

Baron, Jill S.; Seastedt, Timothy; Fagre, Daniel B.; Hicke, Jeffrey A.; Tomback, Diana; Garcia, Elizabeth; Bowen, Zachary H.; Logan, Jesse A.

2013-01-01

In 2002 we published Rocky Mountain Futures, an Ecological Perspective (Island Press) to examine the cumulative ecological effects of human activity in the Rocky Mountains. We concluded that multiple local activities concerning land use, hydrologic manipulation, and resource extraction have altered ecosystems, although there were examples where the “tyranny of small decisions” worked in a positive way toward more sustainable coupled human/environment interactions. Superimposed on local change was climate change, atmospheric deposition of nitrogen and other pollutants, regional population growth, and some national management policies such as fire suppression.

RIVERTON DOME GAS EXPLORATION AND STIMULATION TECHNOLOGY DEMONSTRATION, WIND RIVER BASIN, WYOMING; FINAL

International Nuclear Information System (INIS)

Dr. Ronald C. Surdam

1999-01-01

A primary objective of the Institute for Energy Research (IER)-Santa Fe Snyder Corporation DOE Riverton Dome project is to test the validity of a new conceptual model and resultant exploration paradigm for so-called ''basin center'' gas accumulations. This paradigm and derivative exploration strategy suggest that the two most important elements crucial to the development of prospects in the deep, gas-saturated portions of Rocky Mountain Laramide Basins (RMLB) are (1) the determination and, if possible, three-dimensional evaluation of the pressure boundary between normal and anomalous pressure regimes (i.e., this boundary is typically expressed as a significant inversion in both sonic and seismic velocity-depth profiles) , and (2) the detection and delineation of porosity/permeability ''sweet spots'' (i.e., areas of enhanced storage capacity and deliverability) in potential reservoir targets below this boundary. There are other critical aspects in searching for basin center gas accumulations, but completion of these two tasks is essential to the successful exploration for the unconventional gas resources present in anomalously pressured rock/fluid systems in the Rocky Mountain Laramide Basins. The southern Wind River Basin, in particular the Riverton Dome and Emigrant areas, is a neat location for testing this exploration paradigm. Preliminary work within the Wind River Basin has demonstrated that there is a regionally prominent pressure surface boundary that can be detected by inversions in sonic velocity depth gradients in individual well log profiles and that can be seen as a velocity inversion on seismic lines. Also, the Wind River Basin in general-and the Riverton Dome area specially-is characterized by a significant number of anomalously pressured gas accumulations. Most importantly, Santa Fe Snyder Corporation has provided the study with sonic logs, two 3-D seismic studies (40 mi(sup 2) and 30 mi(sup 2)) and a variety of other necessary geological and

Flathead River Basin Hydrologic Observatory, Northern Rocky Mountains

Science.gov (United States)

Woessner, W. W.; Running, S. W.; Potts, D. F.; Kimball, J. S.; Deluca, T. H.; Fagre, D. B.; Makepeace, S.; Hendrix, M. S.; Lorang, M. S.; Ellis, B. K.; Lafave, J.; Harper, J.

2004-12-01

We are proposing the 22, 515 km2 glacially-sculpted Flathead River Basin located in Montana and British Columbia as a Hydrologic Observatory. This hydrologic landscape is diverse and includes large pristine watersheds, rapidly developing intermountain valleys, and a 95 km2 regulated reservoir and 510 km2 lake. The basin has a topographic gradient of over 2,339 m, and spans high alpine to arid climatic zones and a range of biomes. Stream flows are snow-melt dominated and underpinned by groundwater baseflow. The site headwaters contain 37 glaciers and thousands of square kilometers of watersheds in which fire and disease are the only disturbances. In contrast, the HO also contains watersheds at multiple scales that were dominated by glaciers within the last 100 years but are now glacier free, impacted by timber harvests and fires of varying ages to varying degrees, modified by water management practices including irrigation diversion and dams, and altered by development for homes, cities and agriculture. This Observatory provides a sensitive monitor of historic and future climatic shifts, air shed influences and impacts, and the consequences of land and water management practices on the hydrologic system. The HO watersheds are some of the only pristine watersheds left in the contiguous U.S.. They provide critical habitat for key species including the native threaten bull trout and lynx, and the listed western cutthroat trout, bald eagle, gray wolf and the grizzly bear. For the last several thousand years this system has been dominated by snow-melt runoff and moderated by large quantities of water stored in glacial ice. However, the timing and magnitude of droughts and summer flows have changed dramatically. With the information that can be gleaned from sediment cores and landscape records at different scales, this HO provides scientists with opportunities to establish baseline watershed conditions and data on natural hydrologic variability within the system. Such a

Fish assemblage structure and relations with environmental conditions in a Rocky Mountain watershed

Science.gov (United States)

Quist, M.C.; Hubert, W.A.; Isaak, D.J.

2004-01-01

Fish and habitat were sampled from 110 reaches in the Salt River basin (Idaho and Wyoming) during 1996 and 1997 to assess patterns in fish assemblage structure across a Rocky Mountain watershed. We identified four distinct fish assemblages using cluster analysis: (1) allopatric cutthroat trout (Oncorhynchus clarki (Richardson, 1836)); (2) cutthroat trout - brook trout (Salvelinus fontinalis (Mitchell, 1814)) - Paiute sculpin (Cottus beldingi Eigenmann and Eigenmann, 1891); (3) cutthroat trout - brown trout (Salmo trutta L., 1758) - mottled sculpin (Cottus bairdi Girard, 1850); and (4) Cyprinidae-Catostomidae. The distribution of fish assemblages was explained by thermal characteristics, stream geomorphology, and local habitat features. Reaches with allopatric cutthroat trout and the cutthroat trout - brook trout - Paiute sculpin assemblage were located in high-elevation, high-gradient streams. The other two fish assemblages were generally located in low-elevation streams. Associations between habitat gradients, locations of reaches in the watershed, and occurrence of species were further examined using canonical correspondence analysis. The results suggest that stream geomorphology, thermal conditions, and local habitat characteristics influence fish assemblage structure across a Rocky Mountain watershed, and they provide information on the ecology of individual species that can guide conservation activities. ?? 2004 NRC Canada.

Dateline USA: Settling the West, 1800-1900.

Science.gov (United States)

Chatton, Barbara; O'Laughlin, Michael

1998-01-01

Presents an annotated bibliography of titles related to the theme "Settling the West" which are appropriate for primary, elementary, and middle grades. Topics include overviews of Western history; early 19th century; the gold rush; the pony express; travelers by trail, rail, and ship; settling the West; cowboys and cattle; and the…

Improving Settling Dynamics of Activated Sludge by Adding Fine Talc Powder

DEFF Research Database (Denmark)

Rasmussen, Michael R.; Larsen, Torben; Clauss, F.

1996-01-01

The effect of adding varying mixtures of talc and chlorite powder to activated sludge in order to improve the settling characteristic has been studied. The powder is found to improve the settling velocity of the sludge, strictly by increasing the average density of the sludge floc aggregate. The ....... The settling velocity was measured with a recirculated settling column under different concentrations and turbulence levels. Numerical simulation of a secondary settling tank indicates that adding fine powder will improve the overall performance considerably.......The effect of adding varying mixtures of talc and chlorite powder to activated sludge in order to improve the settling characteristic has been studied. The powder is found to improve the settling velocity of the sludge, strictly by increasing the average density of the sludge floc aggregate...

Predicting multi-scale relationships between geomorphology and bedrock geology of the rocky intertidal in Central and Northern California

Science.gov (United States)

Wheeler, A.; Aiello, I. W.

2014-12-01

Substratum geology is fundamental in shaping rocky shore morphology. Specific lithologies have various responses to wave action, tectonic features (e.g. fractures, faults) and sedimentary structures (e.g. bedding), creating distinctive weathering profiles. Along with local oceanography and climate forcing, different rock substrata create coastal morphologies that can vary distinctly between scales, ranging from mm to km. Despite the complexity of the system, qualitative observations show coastal areas with similar rock types share similar geomorphologies. Thus, a statistic relationship between geomorphology (expressed for instance by surface parameter rugosity) and geology can be envisaged. There are multiple benefits of finding such a relationship, as rocky intertidal geomorphology can be an important determinant in which organisms can settle, grow, and survive in near shore communities: allowing the prediction of geomorphologic parameters determining coastal ecology solely based on substratum geology, a crucial aspect in guiding the selection of marine protected areas. This study presents preliminary results of multi-scale geospatial surveys (cm to tens of meters) of rocky intertidal outcrops from Central to Northern California using a Terrestrial Laser Scanner. The outcrops investigated are representative of the most common igneous and sedimentary rocks in California (granitoids, conglomerates, sandstones, mudstones) and metamorphic units. The statistical analysis of the survey data support the hypothesis that surface properties can change significantly with changing scale, each rock type having distinct surface characteristics which are similar to comparable lithologies exposed at different locations. These scale dependent variations are controlled by different lithologic and structural characteristics of the outcrop in question. Our data also suggests lithologic variability within a rock unit could be a very significant factor in controlling changes in

Manipulation of Cash-Settled Futures Contracts.

OpenAIRE

Pirrong, Craig

2001-01-01

Replacement of delivery settlement of futures contracts with cash settlement is frequently proposed to reduce the frequency of market manipulation. This article shows that it is always possible to design a delivery-settled futures contract that is less susceptible to cornering by a large long than any given cash-settled contract. Such a contract is more susceptible to manipulation by large shorts, however. Therefore, cash settlement does not uniformly dominate delivery settlement as a means o...

Pharmacy settles suit.

Science.gov (United States)

1998-10-02

A suit was filed by an HIV-positive man against a pharmacy that inadvertently disclosed his HIV status to his ex-wife and children. His ex-wife tried to use the information in a custody battle for their two children. The suit against the pharmacy was settled, but the terms of the settlement remain confidential.

A Method for Measuring Sludge Settling Characteristics in Turbulent Flows

DEFF Research Database (Denmark)

Rasmussen, Michael R.; Larsen, Torben

1996-01-01

A method for the determination of the settlilng velocity for sludge as a funktion of turbulence intensity and sludge concentration has been developed. The principle of the method is to continuously feed the top of a settling column with sludge so that a steady state and uniform concentration...... distribution occurs in the middle of the column. This eliminates time scale effects such as flocculation from the measurements, as the resulting settling velocity only can be found at steady state and uniform conditions. The method assumes that flocculated sludge settles faster than disintegratedsludge to make...... a mass balance involving concentration at the top and the middle of the column as well as the inlet sludge flow. The resulting mass balance is used to calculate a lokal settling velocity. The turbulence is introduced by an oscillating grid in the whole depth of the settling column. Settling velocities...

16 CFR 1209.4 - Test procedures for determining settled density.

Science.gov (United States)

2010-01-01

... density. 1209.4 Section 1209.4 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION CONSUMER PRODUCT... procedures for determining settled density. The settled density of lose fill insulation must be determined.... This section describes the procedure for determining the settled density of loose fill insulation. (a...

Controls on the deposition and preservation of the Cretaceous Mowry Shale and Frontier Formation and equivalents, Rocky Mountain region, Colorado, Utah, and Wyoming

Science.gov (United States)

Kirschbaum, Mark A.; Mercier, Tracey J.

2013-01-01

Regional variations in thickness and facies of clastic sediments are controlled by geographic location within a foreland basin. Preservation of facies is dependent on the original accommodation space available during deposition and ultimately by tectonic modification of the foreland in its postthrusting stages. The preservation of facies within the foreland basin and during the modification stage affects the kinds of hydrocarbon reservoirs that are present. This is the case for the Cretaceous Mowry Shale and Frontier Formation and equivalent strata in the Rocky Mountain region of Colorado, Utah, and Wyoming. Biostratigraphically constrained isopach maps of three intervals within these formations provide a control on eustatic variations in sea level, which allow depositional patterns across dip and along strike to be interpreted in terms of relationship to thrust progression and depositional topography. The most highly subsiding parts of the Rocky Mountain foreland basin, near the fold and thrust belt to the west, typically contain a low number of coarse-grained sandstone channels but limited sandstone reservoirs. However, where subsidence is greater than sediment supply, the foredeep contains stacked deltaic sandstones, coal, and preserved transgressive marine shales in mainly conformable successions. The main exploration play in this area is currently coalbed gas, but the enhanced coal thickness combined with a Mowry marine shale source rock indicates that a low-permeability, basin-centered play may exist somewhere along strike in a deep part of the basin. In the slower subsiding parts of the foreland basin, marginal marine and fluvial sandstones are amalgamated and compartmentalized by unconformities, providing conditions for the development of stratigraphic and combination traps, especially in areas of repeated reactivation. Areas of medium accommodation in the most distal parts of the foreland contain isolated marginal marine shoreface and deltaic sandstones

Rocky Mountain spotted fever in children.

Science.gov (United States)

Woods, Charles R

2013-04-01

Rocky Mountain spotted fever is typically undifferentiated from many other infections in the first few days of illness. Treatment should not be delayed pending confirmation of infection when Rocky Mountain spotted fever is suspected. Doxycycline is the drug of choice even for infants and children less than 8 years old. Copyright © 2013 Elsevier Inc. All rights reserved.

Sludge Settling Rate Observations and Projections at the Savannah River Site - 13238

Energy Technology Data Exchange (ETDEWEB)

Gillam, Jeffrey M.; Shah, Hasmukh B.; Keefer, Mark T. [Savannah River Remediation LLC, Aiken SC 29808 (United States)

2013-07-01

Since 2004, sludge batches have included a high percentage of stored sludge generated from the H- modified (HM) process. The slow-settling nature of HM sludge means that the settling is often the major part of the washing tank quiescent period between required pump runs to maintain flammability control. Reasonable settling projections are needed to wash soluble salts from sludge in an efficient manner, to determine how much sludge can be washed in a batch within flammability limits, and to provide composition projections for batch qualification work done in parallel with field preparation. Challenges to providing reasonably accurate settling projections include (1) large variations in settling behavior from tank-to-tank, (2) accounting for changing initial concentrations, sludge masses, and combinations of different sludge types, (3) changing the settling behavior upon dissolving some sludge compounds, and (4) sludge preparation schedules that do not allow for much data collection for a particular sludge before washing begins. Scaling from laboratory settling tests has provided inconsistent results. Several techniques have been employed to improve settling projections and therefore the overall batch preparation efficiency. Before any observations can be made on a particular sludge mixture, projections can only be made based on historical experience with similar sludge types. However, scaling techniques can be applied to historical settling models to account for different sludge masses, concentrations, and even combinations of types of sludge. After sludge washing/settling cycles begin, the direct measurement of the sludge height, once generally limited to a single turbidity meter measurement per settle period, is now augmented by examining the temperature profile in the settling tank, to help determine the settled sludge height over time. Recently, a settling model examined at PNNL [1,2,3] has been applied to observed thermocouple and turbidity meter readings to

Rocky Mountain Spotted Fever: Statistics and Epidemiology

Science.gov (United States)

... Search Form Controls Cancel Submit Search the CDC Rocky Mountain Spotted Fever (RMSF) Note: Javascript is disabled or is not ... message, please visit this page: About CDC.gov . Rocky Mountain Spotted Fever (RMSF) Transmission Signs and Symptoms Diagnosis and Testing ...

Coral larvae settle at a higher frequency on red surfaces

Science.gov (United States)

Mason, B.; Beard, M.; Miller, M. W.

2011-09-01

Although chemical cues serve as the primary determinants of larval settlement and metamorphosis, light is also known to influence the behavior and the settlement of coral planulae. For example, Porites astreoides planulae settle preferentially on unconditioned red substrata. In order to test whether this behavior was a response to color and whether other species also demonstrate color preference, settlement choice experiments were conducted with P. astreoides and Acropora palmata. In these experiments, larvae were offered various types of plastic substrata representing three to seven different color choices. Both species consistently settled on red (or red and orange) substrata at a higher frequency than other colors. In one experiment, P. astreoides settled on 100% of red, plastic cable ties but failed to settle on green or white substrata. In a second experiment, 24% of larvae settled on red buttons, more than settled on six other colors combined. A. palmata settled on 80% of red and of orange cables ties but failed to settle on blue in one experiment and settled on a greater proportion of red acrylic squares than on four other colors or limestone controls in a second experiment. The consistency of the response across a variety of plastic materials suggests the response is related to long-wavelength photosensitivity. Fluorescence and reflectance spectra of experimental substrata demonstrated that the preferred substrata had spectra dominated by wavelengths greater than 550 nm with little or no reflection or emission of shorter wavelengths. These results suggest that some species of coral larvae may use spectral cues for fine-scale habitat selection during settlement. This behavior may be an adaptation to promote settlement in crustose coralline algae (CCA)-dominated habitats facilitating juvenile survival.

Radiation monitor training program at Rocky Flats

International Nuclear Information System (INIS)

Medina, L.C.; Kittinger, W.D.; Vogel, R.M.

The Rocky Flats Radiation Monitor Training Program is tailored to train new health physics personnel in the field of radiation monitoring. The purpose of the prescribed materials and media is to be consistent in training in all areas of Rocky Flats radiation monitoring job involvement

Ancestral Rocky Mountian Tectonics: A Sedimentary Record of Ancestral Front Range and Uncompahgre Exhumation

Science.gov (United States)

Smith, T. M.; Saylor, J. E.; Lapen, T. J.

2015-12-01

The Ancestral Rocky Mountains (ARM) encompass multiple crustal provinces with characteristic crystallization ages across the central and western US. Two driving mechanisms have been proposed to explain ARM deformation. (1) Ouachita-Marathon collision SE of the ARM uplifts has been linked to an E-to-W sequence of uplift and is consistent with proposed disruption of a larger Paradox-Central Colorado Trough Basin by exhumation of the Uncompahgre Uplift. Initial exhumation of the Amarillo-Wichita Uplift to the east would provide a unique ~530 Ma signal absent from source areas to the SW, and result in initial exhumation of the Ancestral Front Range. (2) Alternatively, deformation due to flat slab subduction along a hypothesized plate boundary to the SW suggests a SW-to-NE younging of exhumation. This hypothesis suggests a SW-derived Grenville signature, and would trigger uplift of the Uncompahgre first. We analyzed depositional environments, sediment dispersal patterns, and sediment and basement zircon U-Pb and (U-Th)/He ages in 3 locations in the Paradox Basin and Central Colorado Trough (CCT). The Paradox Basin exhibits an up-section transition in fluvial style that suggests a decrease in overbank stability and increased lateral migration. Similarly, the CCT records a long-term progradation of depositional environments from marginal marine to fluvial, indicating that sediment supply in both basins outpaced accommodation. Preliminary provenance results indicate little to no input from the Amarillo-Wichita uplift in either basin despite uniformly westward sediment dispersal systems in both basins. Results also show that the Uncompahgre Uplift was the source for sediment throughout Paradox Basin deposition. These observations are inconsistent with the predictions of scenario 1 above. Rather, they suggest either a synchronous response to tectonic stress across the ARM provinces or an SW-to-NE pattern of deformation.

Characterization of the settling process for wastewater from a combined sewer system.

Science.gov (United States)

Piro, P; Carbone, M; Penna, N; Marsalek, J

2011-12-15

Among the methods used for determining the parameters necessary for design of wastewater settling tanks, settling column tests are used most commonly, because of their simplicity and low costs. These tests partly mimic the actual settling processes and allow the evaluation of total suspended solids (TSS) removal by settling. Wastewater samples collected from the Liguori Channel (LC) catchment in Cosenza (Italy) were subject to settling column tests, which yielded iso-removal curves for both dry and wet-weather flow conditions. Such curves were approximated well by the newly proposed power law function containing two empirical parameters, a and b, the first of which is the particle settling velocity and the second one is a flocculation factor accounting for deviations from discrete particle settling. This power law function was tested for both the LC catchment and literature data and yielded a very good fit, with correlation coefficient values (R(2)) ranging from 0.93 to 0.99. Finally, variations in the settling tank TSS removal efficiencies with parameters a and b were also analyzed and provided insight for settling tank design. Copyright © 2011 Elsevier Ltd. All rights reserved.

Factors influencing suspended solids concentrations in activated sludge settling tanks.

Science.gov (United States)

Kim, Y; Pipes, W O

1999-05-31

A significant fraction of the total mass of sludge in an activated sludge process may be in the settling tanks if the sludge has a high sludge volume index (SVI) or when a hydraulic overload occurs during a rainstorm. Under those conditions, an accurate estimate of the amount of sludge in the settling tanks is needed in order to calculate the mean cell residence time or to determine the capacity of the settling tanks to store sludge. Determination of the amount of sludge in the settling tanks requires estimation of the average concentration of suspended solids in the layer of sludge (XSB) in the bottom of the settling tanks. A widely used reference recommends averaging the concentrations of suspended solids in the mixed liquor (X) and in the underflow (Xu) from the settling tanks (XSB=0. 5{X+Xu}). This method does not take into consideration other pertinent information available to an operator. This is a report of a field study which had the objective of developing a more accurate method for estimation of the XSB in the bottom of the settling tanks. By correlation analysis, it was found that only 44% of the variation in the measured XSB is related to sum of X and Xu. XSB is also influenced by the SVI, the zone settling velocity at X and the overflow and underflow rates of the settling tanks. The method of averaging X and Xu tends to overestimate the XSB. A new empirical estimation technique for XSB was developed. The estimation technique uses dimensionless ratios; i.e., the ratio of XSB to Xu, the ratio of the overflow rate to the sum of the underflow rate and the initial settling velocity of the mixed liquor and sludge compaction expressed as a ratio (dimensionless SVI). The empirical model is compared with the method of averaging X and Xu for the entire range of sludge depths in the settling tanks and for SVI values between 100 and 300 ml/g. Since the empirical model uses dimensionless ratios, the regression parameters are also dimensionless and the model can be

Geomorphology, hydrology, and ecology of Great Basin meadow complexes - implications for management and restoration

Science.gov (United States)

Jeanne C. Chambers; Jerry R. Miller

2011-01-01

This report contains the results of a 6-year project conducted by the U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station and U.S. Environmental Protection Agency, Office of Research and Development on stream incision and meadow ecosystem degradation in the central Great Basin. The project included a coarse-scale assessment of 56 different...

Settling rates of plutonium-bearing particles in Pond B

International Nuclear Information System (INIS)

Orlandini, K.A.; Bowling, J.W.; Pinder, J.E. III

1986-01-01

Research is being conducted in Pond B to determine the relative importances of (1) changes in particles settling rates, (2) changes in remobilization rates, and (3) the influence of the macrophytes on the annual cycle in /sup 239,240/Pu inventories. The initial research has emphasized (1) an evaluation of the importance of particle adherence to macrophytes in reducing Pu inventories in the water column and (2) measurements of particle settling rates at different times of the year. This report describes the research on measurements of particle settling rates. 3 figures, 1 table

Purification of drilling fluids by vibration-settling tanks

Energy Technology Data Exchange (ETDEWEB)

Bulatov, A.I.; Prokopov, L.I.; Proselkov, Yu.M.; Reznichenko, I.N.; Skvortsov, D.S.; Volkov, A.P.

1982-01-01

Results are presented of studies done by the authors of a prototype of a new tool for cleaning a drilling fluid, a vibration settling tank. It is indicated that the vibration settling tank has many advantages over the most advanced vibration screens VS-1. This makes it possible to recommend development and broad industrial testing of this apparatus.

An experimental study of low concentration sludge settling velocity under turbulent condition.

Science.gov (United States)

Guo, Lisha; Zhang, Daijun; Xu, Danyu; Chen, Yuan

2009-05-01

Particle Image Velocimetry (PIV) was used to study the settling of activated sludge flocs under turbulent flow conditions. Experimental results showed that a larger particle diameter led to a higher settling velocity while the higher turbulence intensity led to lower settling velocity. Based on the measurements a mathematical relation has been derived which correlates the settling velocity for individual sludge flocs under turbulent conditions through a modified Vesilind equation. Settling velocity shows a power-type relation to sludge particle diameter and an exponential-type relation with turbulence intensity and sludge concentration.

Settling-velocity specific SOC distribution on hillslopes

DEFF Research Database (Denmark)

Hu, Yaxian; Berhe, Asmeret Asefaw; Fogel, Marilyn L.

The net effect of soil erosion by water, as a sink or source of atmospheric CO2, is determined by the spatial (re-)distribution and stability of eroded soil organic carbon (SOC). The depositional position of eroded SOC is a function of the transport distances of soil fractions where the SOC...... fractions. Eroding sandy soils and sediment were sampled after a series of rainfall events along a slope on a freshly seeded cropland in Jutland, Denmark. All the soil samples were fractionated into five settling classes using a settling tube apparatus. The spatial distribution of soil settling classes...... shows a coarsening effect immediately below the eroding slope, followed by a fining trend at the slope tail. The 13C values of soil fractions were more positive at the footslope than on the slope shoulder or at the slope tail, suggesting enhanced decomposition rate of fresh SOC input at the footslope...

Long-term Simulation of the Removal of Pollutants in Retention Basins

DEFF Research Database (Denmark)

Larsen, Torben; Neerup-Jensen, Ole; Kaasgaard, Mogens

2005-01-01

-dependant sedimentation and the variation of the settling velocity of the particles. The results show that including these effects lead to significant lower discharges of pollutants compared to conventional methods of estimation. As an example computations with a spectrum of basins which cover realistic sizes show......The paper describes a method for the long-term simulation of the discharge of pollutants to the environment from storm sewer overflows in combined sewer systems, which has a connected retention basin. This study covers Cd, Cu, Ni, Pb, Zn and PAH. The method includes both the influence of the flow...

Gravity settling of precipitated magnetite and ferric floc

International Nuclear Information System (INIS)

Holt, N.S.; Loft, P.R.

1983-06-01

A comparison is presented of the gravity settling performance of ferric floc and magnetite, both in batch settling tests, and on a continuous gravity settler. The precipitation of magnetite from solution on a continuous basis was also demonstrated, and the process was shown not to be significantly affected by the presence of a wide range of chemical species. (U.K.)

Criteria impacting shipments of Rocky Flats Plant radioactive mixed wastes

International Nuclear Information System (INIS)

Clawson, R.L.; Eide, J.H.

1992-05-01

Westinghouse Hanford Company, Transportation and Packaging Division, under contract for the Los Alamos Technology Office-Rocky Flats Plant, has developed this synopsis report to be used as a reference in the development of the Rocky Flats Plant Comprehensive Treatment and Management Plan and the Rocky Flats Plant Residue Elimination Plan. This report represents the criteria for packaging, shipping, and transporting Rocky Flats Plant radioactive mixed wastes. It is a compilation of state and federal regulations, US Department of Energy orders, and acceptance criteria specific to US Department of Energy radioactive mixed waste treatment, storage and disposal facilities

K basins sludge removal sludge pretreatment system

International Nuclear Information System (INIS)

Chang, H.L.

1997-01-01

The Spent Nuclear Fuels Program is in the process of planning activities to remove spent nuclear fuel and other materials from the 100-K Basins as a remediation effort for clean closure. The 105 K- East and K-West Basins store spent fuel, sludge, and debris. Sludge has accumulated in the 1 00 K Basins as a result of fuel oxidation and a slight amount of general debris being deposited, by settling, in the basin water. The ultimate intent in removing the sludge and fuel is to eliminate the environmental risk posed by storing fuel at the K Basins. The task for this project is to disposition specific constituents of sludge (metallic fuel) to produce a product stream through a pretreatment process that will meet the requirements, including a final particle size acceptable to the Tank Waste Remediation System (TWRS). The purpose of this task is to develop a preconceptual design package for the K Basin sludge pretreatment system. The process equipment/system is at a preconceptual stage, as shown in sketch ES-SNF-01 , while a more refined process system and material/energy balances are ongoing (all sketches are shown in Appendix C). Thus, the overall process and 0535 associated equipment have been conservatively selected and sized, respectively, to establish the cost basis and equipment layout as shown in sketches ES- SNF-02 through 08

Settling of virgin olive oil from horizontal screw solid bowl in static conditions.

Science.gov (United States)

Gila, Abraham M; Bejaoui, Mohamed A; Beltrán, Gabriel; Jiménez, Antonio

2017-08-01

This work was aimed to study the clarification efficiency of natural decantation in settling tank on virgin olive oil obtained from a two-ways continuous process. For this purpose, the impurities content of the virgin olive oil were monitored during settling process in settling tank at two different depths. Efficiency of purging system was determined for two days. The experiments were performed at industrial scale during three crop years. During the first minutes of settling was observed an ascent of the smaller organic particles of the oil. Then, most of the virgin olive oil impurities were settled at 300 min, independently of the initial content of virgin olive oil. Finally, oil decantation showed slower rate. Higher clarification values were obtained for those decanter oils with higher impurities content, achieving clarification percentages between of 62.69 and 95.91% at 48 h of settling. The highest settling efficiency was observed for those decanter oils with initial higher impurities content. The purging system used in the settling tanks was not able to remove the most of settled impurities since a considerable amount of the impurities remained in the tank after 48 h, between 13.6 and 71.41% for the studied oils. In the tank purges was observed important oil losses. Therefore, decantation was not an efficient system for oil clarification since its settling capacity varied depending on the initial impurities content and due to the settled impurities can not be removed fully by purging system.

Research and management of soil, plant, animal, and human resources in the Middle Rio Grande Basin

Science.gov (United States)

Deborah M. Finch

1996-01-01

The Rocky Mountain Forest and Range Experiment Station initiated a research program in 1994 called. "Ecology, diversity, and sustainability of soil, plant, animal, and human resources of the Rio Grande Basin". This program is funded by an Ecosystem Management grant from Forest Service Research. Its mission focuses on the development and application of new...

Long Term Estimates of Removal of Heavy Metals and PAH in Retention Basins

DEFF Research Database (Denmark)

Larsen, Torben; Neerup-Jensen, O.

2004-01-01

The paper describes a method for the long-term simulation of the discharge of pollutants to the environment from storm sewer overflows in combined sewer systems, which have a connected retention basins. This study covers heavy metals (Cd, Cu, Ni, Pb, Zn) and PAH. The method includes both...... the influence of the flow-dependant sedimentation and the variation of the settling velocity of the particles. The results show that including these effects lead to significant lower discharges of pollutants compared to conventional methods of estimation. As an example computations with a spectrum of basins...

A phenomenological retention tank model using settling velocity distributions.

Science.gov (United States)

Maruejouls, T; Vanrolleghem, P A; Pelletier, G; Lessard, P

2012-12-15

Many authors have observed the influence of the settling velocity distribution on the sedimentation process in retention tanks. However, the pollutants' behaviour in such tanks is not well characterized, especially with respect to their settling velocity distribution. This paper presents a phenomenological modelling study dealing with the way by which the settling velocity distribution of particles in combined sewage changes between entering and leaving an off-line retention tank. The work starts from a previously published model (Lessard and Beck, 1991) which is first implemented in a wastewater management modelling software, to be then tested with full-scale field data for the first time. Next, its performance is improved by integrating the particle settling velocity distribution and adding a description of the resuspension due to pumping for emptying the tank. Finally, the potential of the improved model is demonstrated by comparing the results for one more rain event. Copyright © 2011 Elsevier Ltd. All rights reserved.

Temporal variation of floc size and settling velocity in the Dollard estuary

Science.gov (United States)

Van der Lee, Willem T. B.

2000-09-01

Temporal changes in floc size and settling velocity were measured in the Dollard estuary with an under water video camera. The results show that the flocs in the Dollard are very heterogeneous and that larger flocs have much lower effective densities than smaller flocs. Due to this density decrease, floc settling velocities show only a minor increase with increasing floc size. Floc sizes and settling velocities correlate with the suspended sediment concentration (SSC) on a tidal time scale, but not on a seasonal time scale. On a seasonal time scale floc sizes depend on the binding properties of the sediment, while floc settling velocities show hardly any variation, as an increase in floc size is mainly counterbalanced by a decrease in floc density. Tidal variations in settling velocity occur but cannot be modeled solely as a function of SSC, as the relation between floc size/settling velocity and SSC constantly changes in time and space. Settling velocity variations throughout the tide can however be expressed as a function of tidal phase.

Public involvement in cleanup - the Rocky Flats experience

International Nuclear Information System (INIS)

Paukert, J.; Pennock, S.; Schassburger, R.

1992-01-01

The U.S. Department of Energy's Rocky Flats Plant recently completed and implemented the Rocky Flats Plant Community Relations Plan for public involvement in environmental restoration of the site. The plan was developed in cooperation with the plant's regulators, the U.S. Environmental Protection Agency and the Colorado Department of Health. In addition, citizens near the plant played a significant role in shaping the document through extensive community interviews and public comment. The result of these cooperative efforts is a plan that meets and exceeds the applicable federal and state community relations requirements for a cleanup program. In fact, the U.S. Environmental Protection Agency has used the Rocky Flats Plant Community Relations Plants a model for similar plans at other federal facilities. Plan development, however, is only the starting point for an effective community relations effort. The Rocky Flats Plant and the public will face many challenges together as we implement the plan and build a partnership for addressing environmental cleanup issues. (author)

Rocky desertification in Southwest China: Impacts, causes, and restoration

Science.gov (United States)

Jiang, Zhongcheng; Lian, Yanqing; Qin, Xiaoqun

2014-05-01

Rocky desertification, which is relatively less well known than desertification, refers to the processes and human activities that transform a karst area covered by vegetation and soil into a rocky landscape. It has occurred in various countries and regions, including the European Mediterranean and Dinaric Karst regions of the Balkan Peninsula, Southwest China on a large scale, and alarmingly, even in tropical rainforests such as Haiti and Barbados, and has had tremendous negative impacts to the environment and social and economic conditions at local and regional scales. The goal of this paper is to provide a thorough review of the impacts, causes, and restoration measures of rocky desertification based on decades of studies in the southwest karst area of China and reviews of studies in Europe and other parts of the world. The low soil formation rate and high permeability of carbonate rocks create a fragile and vulnerable environment that is susceptible to deforestation and soil erosion. Other natural processes related to hydrology and ecology could exacerbate rocky desertification. However, disturbances from a wide variety of human activities are ultimately responsible for rocky desertification wherever it has occurred. This review shows that reforestation can be successful in Southwest China and even in the Dinaric Karst region when the land, people, water, and other resources are managed cohesively. However, new challenges may arise as more frequent droughts and extreme floods induced by global climate change and variability may slow the recovery process or even expand rocky desertification. This review is intended to bring attention to this challenging issue and provide information needed to advance research and engineering practices to combat rocky desertification and to aid in sustainable development.

The rocky flats controversy on radionuclide soil action levels

International Nuclear Information System (INIS)

Earle, T.C.

2004-01-01

This report describes how stakeholder involvement processes led to the successful resolution of a dispute over radionuclide soil action levels at the Rocky Flats Site near Denver, Colorado. During the Cold War Era, Rocky Flats, a plutonium fabrication plant, was part of the American government's multi-site nuclear weapons production facilities. Although the Rocky Flats plant had significant positive effects on the local economy, it became a target of public protest due to concerns over both public safety in the area surrounding the site and global nuclear proliferation. In the late 1980's, local safety concerns led to investigations by state and federal agencies. In 1992, with the Cold War ended, the Department of Energy decided to decommission the Rocky Flats site and to begin the long process of decontamination. (author)

On the hindered settling of suspensions of mud and mud-sand mixtures

NARCIS (Netherlands)

Dankers, P.J.T.

2006-01-01

Highly concentrated suspensions are present in many natural environments. When the concentration becomes large enough, particles start to interfere with each other and their settling velocity reduces. This is called hindered settling. As a result of the reduced settling velocity, particles remain in

Occurrence and distribution of heavy metals in indoor settled ...

African Journals Online (AJOL)

The results showed widespread heavy metals contamination especially Fe and Zn, which were present as the highest concentration while Cd was the lowest in the settled particles (dust). The order of occurrence of heavy metals in settled particles (dust) collected indoor in 2007 and 2008 respectively were as follows, ...

Multiphase modeling of settling and suspension in anaerobic digester

International Nuclear Information System (INIS)

Yu, Liang; Ma, Jingwei; Frear, Craig; Zhao, Quanbao; Dillon, Robert; Li, Xiujin; Chen, Shulin

2013-01-01

Highlights: • Develop biowaste fluid dynamics for collision, aggregation and breakup of clusters. • Explore the mechanisms of settling and suspension in anaerobic digester. • Biowaste particles tended to have fluid properties. • Aided with CFD simulation, the scale-up effect was reduced. - Abstract: Effective suspension and settling are critical for controlling biomass retention in a bioreactor. In this paper, a multi-fluid model with kinetic theory of granular flow (KTGF) was established to describe these phenomena in the biowaste particles flow in anaerobic digesters. Solid retention time (SRT) was added as a parameter into anaerobic digestion No.1 (ADM1) model to evaluate its effect on the biogas productivity. The model was experimentally validated in a liquid–gas–solid column reactor with gas and solid volume fraction and granular temperature as the major variables. The wastewater residence time distribution was also determined through modeling and measurement to evaluate the mixing pattern in the pilot column reactor. The effect of restitution coefficient on flow behavior of biowaste particles, particles settling and suspension were predicted. Settling and suspension processes of anaerobic digesters were simulated for lab and pilot-scale reactors with comparisons made for reactor configuration and geometry model, respectively. This study demonstrated that the multi-fluid model with KTGF could provide better understanding of impact of suspension and settling upon retaining biomass particles in the anaerobic digesters

State geothermal commercialization programs in seven Rocky Mountain states. Semiannual progress report, July-December 1980

Energy Technology Data Exchange (ETDEWEB)

Lunis, B. C.; Toth, W. J. [comps.

1981-10-01

The activities and findings of the seven state commercialization teams participating in the Rocky Mountain Basin and Range commercialization program are described. Background information is provided; program objectives and the technical approach that is used are discussed; and the benefits of the program are described. The summary of findings is presented. Prospect identification, area development plans, site specific development analyses, time-phased project plans, the aggregated prospective geothermal energy use, and institutional analyses are discussed. Public outreach activities are covered and findings and recommendations are summarized. The commercialization activities carried out by the respective state teams are described for the following: Colorado, Montana, New Mexico, North Dakota, South Dakota, Utah, and Wyoming.

Experimental analysis of turbulence effect in settling velocity of suspended sediments

Directory of Open Access Journals (Sweden)

H. Salinas–Tapia

2008-01-01

Full Text Available Settling velocities of sediment particles for different size ranges were measured in this work using PIV with the help of discriminatory filters. An experimental channel 10x15 cm cross section was used in order to obtain two set of turbulent characteristics corresponding with two different flow rates. The purpose was to analyze the effect of turbulence on the solids settling velocity. The technique allowed us to measure the individual settling velocity of the particles and the flow velocity field of the fluid. Capture and image analysis was performed with digital cameras (CCD using the software Sharp–provision PIV and the statistical cross correlation technique. Results showed that settling velocity of particles is affected by turbulence which enhances the fluid drag coefficient. Physical explanation of this phenomenon is related with the magnitude of the vertical fluctuating velocity of the fluid. However, more research is needed in order to define settling velocity formulas that takes into account this effect

An analysis of multiple particle settling for LMR backup shutdown systems

International Nuclear Information System (INIS)

Brock, R.W.

1992-05-01

Backup shutdown systems proposed for future LMRs may employ discreet absorber particles to provide the negative reactivity insertion. When actuated, these systems release a dense packing of particles from an out-of-core region to settle into an in-core region. The multiple particle settling behavior is analyzed by the method of continuity waves. This method provides predictions of the dynamic response of the system including the average particle velocity and volume fraction of particles vs. time. Although hindered settling problems have been previously analyzed using continuity wave theory, this application represents an extension of the theory to conditions of unrestrained settling. Typical cases are analyzed and numerical results are calculated based on a semi-empirical drift-flux model. For 1/4-inch diameter boron-carbide particles in hot liquid sodium, the unrestrained settling problem assumes a steady-state solution when the average volume fraction of particles is 0.295 and the average particle velocity is 26.0 cm/s

Study on comprehensive planning of rocky desertification in karst area of Chongqing

Science.gov (United States)

Zang, Yajun

2017-11-01

Chongqing is a key area for comprehensive treatment of rocky desertification in karst areas of china. Strengthening the comprehensive management of karst rocky desertification area, for the maintenance of ecological safety of Three Gorges Reservoir area, expanding the karst rocky desertification area people survival and development space, and improving the regional ecological conditions, have important practical significance to the construction of ecological civilization and building a harmonious society. Based on the investigation, analysis and arrangement of the data in the rocky desertification area, the paper puts forward the corresponding measures and phased targets for the treatment of the Rocky Desertification in the karst areas of Chongqing.

Rocky Flats Cleanup Agreement implementation successes and challenges

International Nuclear Information System (INIS)

Shelton, D.C.

1997-01-01

On July 19, 1996 the US Department of Energy (DOE), State of Colorado (CDPHE), and US Environmental Protection Agency (EPA) entered into an agreement called the Rocky Flats Cleanup Agreement (RFCA) for the cleanup and closure of the Rocky Flats Environmental Technology Site (RFETS or Rocky Flats). Major elements of the agreement include: an Integrated Site-Wide Baseline; up to twelve significant enforceable milestones per year; agreed upon soil and water action levels and standards for cleanup; open space as the likely foreseeable land use; the plutonium and TRU waste removed by 2015; streamlined regulatory process; agreement with the Defense Nuclear Facilities Safety Board (DNFSB) to coordinate activities; and a risk reduction focus. Successful implementation of RFCA requires a substantial effort by the parties to change their way of thinking about RFETS and meet the deliverables and commitments. Substantial progress toward Site closure through the implementation of RFCA has been accomplished in the short time since the signing, yet much remains to be done. Much can be learned from the Rocky Flats experience by other facilities in similar situations

Flocculation and Settling Velocity Estimates for Reservoir Sedimentation Analysis

Science.gov (United States)

2016-02-01

viscosity ). Stokes’ law is commonly used to describe settling velocity of a single particle and is applicable when the particle Reynolds number (Rep...fluid viscosity , and ν is kinematic viscosity . Several researchers recognize that large, fast-settling particles disobey the laminar boundary...interparticle attraction caused by electrostatic and physiochemical forces. These properties give clays their stickiness and control essential

ROCKY PLANETESIMAL FORMATION VIA FLUFFY AGGREGATES OF NANOGRAINS

Energy Technology Data Exchange (ETDEWEB)

Arakawa, Sota; Nakamoto, Taishi, E-mail: arakawa.s.ac@m.titech.ac.jp [Department of Earth and Planetary Sciences, Tokyo Institute of Technology, Meguro, Tokyo 152-8551 (Japan)

2016-12-01

Several pieces of evidence suggest that silicate grains in primitive meteorites are not interstellar grains but condensates formed in the early solar system. Moreover, the size distribution of matrix grains in chondrites implies that these condensates might be formed as nanometer-sized grains. Therefore, we propose a novel scenario for rocky planetesimal formation in which nanometer-sized silicate grains are produced by evaporation and recondensation events in early solar nebula, and rocky planetesimals are formed via aggregation of these nanograins. We reveal that silicate nanograins can grow into rocky planetesimals via direct aggregation without catastrophic fragmentation and serious radial drift, and our results provide a suitable condition for protoplanet formation in our solar system.

Coal fly ash basins as an attractive nuisance to birds: Parental provisioning exposes nestlings to harmful trace elements

International Nuclear Information System (INIS)

Bryan, A.L.; Hopkins, W.A.; Parikh, J.H.; Jackson, B.P.; Unrine, J.M.

2012-01-01

Birds attracted to nest around coal ash settling basins may expose their young to contaminants by provisioning them with contaminated food. Diet and tissues of Common Grackle (Quiscalus quiscala) nestlings were analyzed for trace elements to determine if nestlings were accumulating elements via dietary exposure and if feather growth limits elemental accumulation in other tissues. Arsenic, cadmium, and selenium concentrations in ash basin diets were 5× higher than reference diets. Arsenic, cadmium, and selenium concentrations were elevated in feather, liver, and carcass, but only liver Se concentrations approached levels of concern. Approximately 15% of the total body burden of Se, As, and Cd was sequestered in feathers of older (>5 days) nestlings, whereas only 1% of the total body burden of Sr was sequestered in feathers. Feather concentrations of only three elements (As, Se, and Sr) were correlated with liver concentrations, indicating their value as non-lethal indicators of exposure. - Highlights: ► We examined elemental uptake by grackle nestlings associated with coal ash basins. ► Diet of ash basin nestlings had higher levels of Se, As, and Cd than control nestlings. ► Se, As, Cd, and Sr concentrations of ash basin nestling tissues were elevated. ► Only Se in nestling liver approached published levels of concern. ► Nestling feathers sequestered >15% of the total body burden of Se, As, and Cd. - Nestlings of common grackles attracted to nest around coal ash settling basins were exposed to elevated dietary Se, As, Cd, and Sr, resulting in elevated Se tissue concentrations approaching reported levels of concern.

Measuring and modeling the magnetic settling of superparamagnetic nanoparticle dispersions.

Science.gov (United States)

Prigiobbe, Valentina; Ko, Saebom; Huh, Chun; Bryant, Steven L

2015-06-01

In this paper, we present settling experiments and mathematical modeling to study the magnetic separation of superparamagnetic iron-oxide nanoparticles (SPIONs) from a brine. The experiments were performed using SPIONs suspensions of concentration between 3 and 202g/L dispersed in water and separated from the liquid under the effect of a permanent magnet. A 1D model was developed in the framework of the sedimentation theory with a conservation law for SPIONs and a mass flux function based on the Newton's law for motion in a magnetic field. The model describes both the hindering effect of suspension concentration (n) during settling due to particle collisions and the increase in settling rate due to the attraction of the SPIONs towards the magnet. The flux function was derived from the settling experiments and the numerical model validated against the analytical solution and the experimental data. Suspensions of SPIONs were of 2.8cm initial height, placed on a magnet, and monitored continuously with a digital camera. Applying a magnetic field of 0.5T of polarization, the SPION's velocity was of approximately 3·10(-5)m/s close to the magnet and decreases of two orders of magnitude across the domain. The process was characterized initially by a classical sedimentation behavior, i.e., an upper interface between the clear water and the suspension slowly moving towards the magnet and a lower interface between the sediment layer and the suspension moving away from the magnet. Subsequently, a rapid separation of nanoparticle occured suggesting a non-classical settling phenomenon induced by magnetic forces which favor particle aggregation and therefore faster settling. The rate of settling decreased with n and an optimal condition for fast separation was found for an initial n of 120g/L. The model agrees well with the measurements in the early stage of the settling, but it fails to describe the upper interface movement during the later stage, probably because of particle

Aggregate Settling Velocities in San Francisco Estuary Margins

Science.gov (United States)

Allen, R. M.; Stacey, M. T.; Variano, E. A.

2015-12-01

One way that humans impact aquatic ecosystems is by adding nutrients and contaminants, which can propagate up the food web and cause blooms and die-offs, respectively. Often, these chemicals are attached to fine sediments, and thus where sediments go, so do these anthropogenic influences. Vertical motion of sediments is important for sinking and burial, and also for indirect effects on horizontal transport. The dynamics of sinking sediment (often in aggregates) are complex, thus we need field data to test and validate existing models. San Francisco Bay is well studied and is often used as a test case for new measurement and model techniques (Barnard et al. 2013). Settling velocities for aggregates vary between 4*10-5 to 1.6*10-2 m/s along the estuary backbone (Manning and Schoellhamer 2013). Model results from South San Francisco Bay shoals suggest two populations of settling particles, one fast (ws of 9 to 5.8*10-4 m/s) and one slow (ws of Brand et al. 2015). While the open waters of San Francisco Bay and other estuaries are well studied and modeled, sediment and contaminants often originate from the margin regions, and the margins remain poorly characterized. We conducted a 24 hour field experiment in a channel slough of South San Francisco Bay, and measured settling velocity, turbulence and flow, and suspended sediment concentration. At this margin location, we found average settling velocities of 4-5*10-5 m/s, and saw settling velocities decrease with decreasing suspended sediment concentration. These results are consistent with, though at the low end of, those seen along the estuary center, and they suggest that the two population model that has been successful along the shoals may also apply in the margins.

The challenge and future of rocky desertification control in karst areas in southwest China

Science.gov (United States)

Zhang, J. Y.; Dai, M. H.; Wang, L. C.; Zeng, C. F.; Su, W. C.

2016-01-01

Karst rocky desertification occurs after vegetation deteriorates as a result of intensive land use, which leads to severe water loss and soil erosion and exposes basement rocks, creating a rocky landscape. Karst rocky desertification is found in humid areas in southwest China, the region most seriously affected by rocky desertification in the world. In order to promote ecological restoration and help peasants out of poverty, the Chinese government carried out the first phase of a rocky desertification control project from 2006 to 2015, which initially contained the expansion of rocky desertification. Currently, the Chinese government is prepared to implement the second phase of the rocky desertification control project, and therefore it is essential to summarise the lessons learned over the last 10 years of the first phase. In this paper, we analyse the driving social and economic factors behind rocky desertification, summarise the scientific research on rocky desertification in the region, and finally identify the main problems facing rocky desertification control. In addition, we put forward several policy suggestions that take into account the perspective of local peasants, scientific research, and China's economic development and urbanisation process. These suggestions include promoting the non-agriculturalization of household livelihoods, improving ecological compensation, strengthening the evaluation of rocky desertification control and dynamic monitoring, and strengthening research on key ecological function recovery technologies and supporting technologies.

Rocky Mountain Riparian Digest

Science.gov (United States)

Deborah M. Finch

2008-01-01

The Rocky Mountain Riparian Digest presents the many facets of riparian research at the station. Included are articles about protecting the riparian habitat, the social and economic values of riparian environments, watershed restoration, remote sensing tools, and getting kids interested in the science.

Sampling and analysis plan for the 116-C-5 retention basins characteristic dangerous waste determination

International Nuclear Information System (INIS)

Bauer, R.G.; Dunks, K.L.

1996-03-01

Cooling water flow from the rear face of the 100-B and 100-C reactors was diverted to large retention basins prior to discharge to the Columbia River. These retention basins delayed the release of the reactor coolant for decay of the short-lived activation products and for thermal cooling. Some of the activation products were deposited in sludge that settled in the basins and discharge lines. In addition, some contamination was deposited in soil around the basins and associated piping. The sampling objective of this project is to determine if regulated levels of leachable lead are present in the abrasive materials used to decontaminate the retention basin tank walls, in the material between the tank base plate and the concrete foundation, and in the soils immediately surrounding the perimeter of the retention basins. Sampling details, including sampling locations, frequencies, and analytical requirements, are discussed. Also described is the quality assurance plan for this project

A case of Rocky Mountain spotted fever.

Science.gov (United States)

Rubel, Barry S

2007-01-01

Rocky Mountain spotted fever is a serious, generalized infection that is spread to humans through the bite of infected ticks. It can be lethal but it is curable. The disease gets its name from the Rocky Mountain region where it was first identified in 1896. The fever is caused by the bacterium Rickettsia rickettsii and is maintained in nature in a complex life cycle involving ticks and mammals. Humans are considered to be accidental hosts and are not involved in the natural transmission cycle of this pathogen. The author examined a 47-year-old woman during a periodic recall appointment. The patient had no dental problems other than the need for routine prophylaxis but mentioned a recent problem with swelling of her extremities with an accompanying rash and general malaise and soreness in her neck region. Tests were conducted and a diagnosis of Rocky Mountain spotted fever was made.

Floristic similarity and dispersal syndromes in a rocky outcrop in semi-arid Northeastern Brazil.

Science.gov (United States)

Costa, Elainne Cristina Silva; Lopes, Sérgio de Faria; Melo, José Iranildo Miranda de

2015-09-01

Floristic studies provide valuable information on species richness in a region, and are particularly important if these areas belong to less studied environments, such as rocky outcrops, that may increase our knowledge. An important aspect for species colonization includes the mechanisms of diaspores dispersal in each community; these are essential to understand its structure, dynamics, and the regeneration process, and constitute an important tool for conservation. We developed a floristic survey on a granite-gneiss outcrop with the objective to increase the knowledge on plant diversity, through a floristic similarity analysis and detection of dispersal syndromes of sampled species, in a semi-arid region of Brazil. The fieldwork included collection and observation of the botanical material in loco during a period of 12 months. A total of 161 species belonging to 127 genera and 50 families of angiosperms were recorded. Fabaceae, Asteraceae and Convolvulaceae were the most representative families in number of species. Allophylus quercifolius (Mart.) Radlk. (Capparaceae) and Lafoensia pacari A. St.-Hil. (Lythraceae) represented new records for the State of Paraiba. The autochoric syndrome was the most representative, with 51.5 % of the recorded species; the anemochory was the second most representative syndrome with 26.7 % of the species; and finally the zoochory, representing 22.3 % of the species. The floristic similarity dendrogram showed the formation of three well-defined groups, whose area with the highest value (J = 33.2) is located in a Caatinga region called Cariri Paraibano, while the lowest value observed (J = 5.2), occurred in a settled area in two geomorphological units, a crystalline complex and a plateau region. These results may be due to the varying topographic conditions and edaphic heterogeneity arising from the specific geological formation of the region. These results yet demonstrate that, in rocky outcrops, abiotic syndromes represent an

Grain-resolving simulations of settling cohesive sediment

Science.gov (United States)

Vowinckel, Bernhard; Whithers, Jade; Meiburg, Eckart; Luzzatto-Fegiz, Paolo

2017-11-01

Cohesive sediment is ubiquitous in natural environments such as rivers, lakes and coastal ecosystems. For this type of sediment, we can no longer ignore the short-range attractive forces that result in flocculation of aggregates much larger than the individual grain size. Hence, understanding the complex dynamics of the interplay between flocculated sediment and the ambient fluid is of prime interest for managing aquatic environments, although a comprehensive understanding of these phenomena is still lacking. In the present study, we address this issue by carrying out grain-resolved simulations of cohesive particles settling under gravity using the Immersed Boundary Method. We present a computational model formulation to accurately resolve the process of flocculation. The cohesive model is then applied to a complex test case. A randomly distributed ensemble of 1261 polydisperse particles is released in a tank of quiescent fluid. Subsequently, particles start to settle, thereby replacing fluid at the bottom of the tank, which induces a counter flow opposing the settling direction. This mechanism will be compared to experimental studies from the literature, as well as to the non-cohesive counterpart to assessthe impact of flocculation on sedimentation.

Managing Rocky Mountain spotted fever.

Science.gov (United States)

Minniear, Timothy D; Buckingham, Steven C

2009-11-01

Rocky Mountain spotted fever is caused by the tick-borne bacterium Rickettsia rickettsii. Symptoms range from moderate illness to severe illness, including cardiovascular compromise, coma and death. The disease is prevalent in most of the USA, especially during warmer months. The trademark presentation is fever and rash with a history of tick bite, although tick exposure is unappreciated in over a third of cases. Other signature symptoms include headache and abdominal pain. The antibiotic therapy of choice for R. rickettsii infection is doxycycline. Preventive measures for Rocky Mountain spotted fever and other tick-borne diseases include: wearing long-sleeved, light colored clothing; checking for tick attachment and removing attached ticks promptly; applying topical insect repellent; and treating clothing with permethrin.

Bed turbulent kinetic energy boundary conditions for trapping efficiency and spatial distribution of sediments in basins.

Science.gov (United States)

Isenmann, Gilles; Dufresne, Matthieu; Vazquez, José; Mose, Robert

2017-10-01

The purpose of this study is to develop and validate a numerical tool for evaluating the performance of a settling basin regarding the trapping of suspended matter. The Euler-Lagrange approach was chosen to model the flow and sediment transport. The numerical model developed relies on the open source library OpenFOAM ® , enhanced with new particle/wall interaction conditions to limit sediment deposition in zones with favourable hydrodynamic conditions (shear stress, turbulent kinetic energy). In particular, a new relation is proposed for calculating the turbulent kinetic energy threshold as a function of the properties of each particle (diameter and density). The numerical model is compared to three experimental datasets taken from the literature and collected for scale models of basins. The comparison of the numerical and experimental results permits concluding on the model's capacity to predict the trapping of particles in a settling basin with an absolute error in the region of 5% when the sediment depositions occur over the entire bed. In the case of sediment depositions localised in preferential zones, their distribution is reproduced well by the model and trapping efficiency is evaluated with an absolute error in the region of 10% (excluding cases of particles with very low density).

Heavy Metal and PAH Concentrations in Highway Runoff Deposits Fractionated on Settling Velocities

DEFF Research Database (Denmark)

Bentzen, Thomas Ruby; Larsen, Torben

2009-01-01

The correlation between settling velocity and associated pollutant concentrations is of major importance for best management practice in designing, redesigning, or evaluation of the efficiency of existing pond facilities for retaining unwanted pollutants. The prospect of this note is to state...... the relationship between the settling velocity of the runoff particles and the corresponding metal and polyaromatic hydrocarbon (PAH) concentration directly instead of dealing with two unknowns-the density and the shape of a single particle fraction in a settling velocity calculations. The measurements show...... and copper and there is no significant correlation between PAH concentration and settling velocity. The largest mass of metals and PAH within each pond can be found on the particle fraction with a settling velocity of 5.5-2.5 mm/s....

Factors controlling floc settling velocity along a longitudinal estuarine transect

Science.gov (United States)

Manning, A.J.; Schoellhamer, D.H.

2013-01-01

A 147 km longitudinal transect of flocculated cohesive sediment properties in San Francisco Bay (SFB) was conducted on June 17th, 2008. Our aim was to determine the factors that control floc settling velocity along the longitudinal axis of the estuary. The INSSEV-LF video system was used to measure floc diameters and settling velocities at 30 stations at a distance of 0.7 m above the estuary bed. Floc sizes (D) ranged from 22 μm to 639 μm and settling velocities (Ws) ranged between 0.04 mm·s− 1 and 15.8 mm·s− 1 during the longitudinal transect. Nearbed turbulent shear stresses throughout the transect duration were within the 0.2–0.5 Pa range which typically stimulates flocculation growth. The individual D–Ws–floc density plots suggest the suspended sediments encountered throughout SFB were composed of both muddy cohesive sediment and mixed sediments flocs. Mass-weighted population mean settling velocity (Wsmass) ranged from 0.5 mm·s− 1 to 10 mm·s− 1. The macrofloc and microfloc (demarcation at 160 μm) sub-populations demonstrated parameterised settling velocities which spanned nearly double the range of the sample mean settling velocities (Wsmean). The macroflocs tended to dominate the suspended mass (up to 77% of the ambient suspended solid concentration; SSC) from San Pablo Bay to Carquinez Strait (the vicinity of the turbidity maximum zone). Microfloc mass was particularly significant (typically 60–100% of the SSC) in the northern section of South Bay and most of Central Bay. The transect took eleven hours to complete and was not fully synoptic. During slack tide, larger and faster settling flocs deposited, accounting for most of the longitudinal variability. The best single predictor of settling velocity was water velocity 39 min prior to sampling, not suspended-sediment concentration or salinity. Resuspension and settling lags are likely responsible for the lagged response of settling velocity to water velocity. The distribution of

A numerical method for investigating crystal settling in convecting magma chambers

Science.gov (United States)

Verhoeven, J.; Schmalzl, J.

2009-12-01

Magma chambers can be considered as thermochemically driven convection systems. We present a new numerical method that describes the movement of crystallized minerals in terms of active spherical particles in a convecting magma that is represented by an infinite Prandtl number fluid. The main part focuses on the results we obtained. A finite volume thermochemical convection model for two and three dimensions and a discrete element method, which is used to model granular material, are combined. The new model is validated with floating experiments using particles of different densities and an investigation of single and multiparticle settling velocities. The resulting velocities are compared with theoretical predictions by Stokes's law and a hindered settling function for the multiparticle system. Two fundamental convection regimes are identified in the parameter space that is spanned by the Rayleigh number and the chemical Rayleigh number, which is a measure for the density of the particles. We define the T regime that is dominated by thermal convection. Here the thermal driving force is strong enough to keep all particles in suspension. As the particles get denser, they start settling to the ground, which results in a C regime. The C regime is characterized by the existence of a sediment layer with particle-rich material and a suspension layer with few particles. It is shown that the presence of particles can reduce the vigor of thermal convection. In the frame of a parameter study we discuss the change between the regimes that is systematically investigated. We show that the so-called TC transition fits a power law. Furthermore, we investigate the settling behavior of the particles in vigorous thermal convection, which can be linked to crystal settling in magma chambers. We develop an analytical settling law that describes the number of settled particles against time and show that the results fit the observations from numerical and laboratory experiments.

DUST AND GAS IN THE DISK OF HL TAURI: SURFACE DENSITY, DUST SETTLING, AND DUST-TO-GAS RATIO

Energy Technology Data Exchange (ETDEWEB)

Pinte, C.; Ménard, F. [UMI-FCA, CNRS/INSU, France (UMI 3386), and Dept. de Astronomía, Universidad de Chile, Santiago (Chile); Dent, W. R. F.; Hales, A.; Hill, T.; Cortes, P.; Gregorio-Monsalvo, I. de, E-mail: christophe.pinte@obs.ujf-grenoble.fr [Atacama Large Millimeter/Submillimeter Array, Joint ALMA Observatory, Alonso de Córdova 3107, Vitacura 763-0355, Santiago (Chile)

2016-01-01

The recent ALMA observations of the disk surrounding HL Tau reveal a very complex dust spatial distribution. We present a radiative transfer model accounting for the observed gaps and bright rings as well as radial changes of the emissivity index. We find that the dust density is depleted by at least a factor of 10 in the main gaps compared to the surrounding rings. Ring masses range from 10–100 M{sub ⊕} in dust, and we find that each of the deepest gaps is consistent with the removal of up to 40 M{sub ⊕} of dust. If this material has accumulated into rocky bodies, these would be close to the point of runaway gas accretion. Our model indicates that the outermost ring is depleted in millimeter grains compared to the central rings. This suggests faster grain growth in the central regions and/or radial migration of the larger grains. The morphology of the gaps observed by ALMA—well separated and showing a high degree of contrast with the bright rings over all azimuths—indicates that the millimeter dust disk is geometrically thin (scale height ≈1 AU at 100 AU) and that a large amount of settling of large grains has already occurred. Assuming a standard dust settling model, we find that the observations are consistent with a turbulent viscosity coefficient of a few 10{sup −4}. We estimate the gas/dust ratio in this thin layer to be of the order of 5 if the initial ratio is 100. The HCO{sup +} and CO emission is consistent with gas in Keplerian motion around a 1.7 M{sub ⊙} star at radii from ≤10–120 AU.

Optimization of the static occlusion by "occlusal surface settling" in the Cerec 3D software.

Science.gov (United States)

Späth, C; Kordass, B

2006-04-01

The adjustment of the static occlusion can be automated in computer-based systems. The Cerec 3D software makes it possible to take preformed occlusal surfaces from a database and adapt them to the antagonist. In this adaptation (settling), the CAD occlusal surface "settles" as whole or each cusp individually into the occlusal surface of the antagonist until stable occlusion is reached. Two occlusal surface shapes were compared: Vita Physiodens and Lee Culp. An index was formed from the number, quality, and position of the occlusal contacts for 35 model cases (25 molars, 10 premolars). With regard to the settling of the total occlusal surfaces, there were no differences between the two occlusal surface shapes. In "cusp settling" of the molars, Vita Physiodens performed significantly better. In the comparison of the 1st with the 3rd settling process, significant improvements occurred the 3rd time in many cases when settling individual cusps, but in clearly fewer cases in the settling process of the total occlusal surface. The Lee Culp tooth occlusion improved especially after the 3rd settling process of individual cusps. It is therefore expedient to combine both settling versions with one another.

Nodalisation of the Marviken pressuriser and inter-volume gravitational settling

International Nuclear Information System (INIS)

Williams, D.A.

1989-04-01

A long-standing issue in the calculation of aerosol transport phenomena is the treatment of gravitational sedimentation in volumes which have no real settling surfaces. The VICTORIA primary circuit computer code has been extended to model inter-volume settling, and has been used to evaluate the importance of this mechanism for Marviken test 2b. The main conclusion of this study is that the neglect of inter-volume settling may result in the distortion of predicted deposition profiles and aerosol size distributions under certain conditions. These errors in the predicted aerosol behaviour may then give rise to further complications downstream. The results of the VICTORIA calculations are in good agreement with the data from test 2b. (author)

The rocky flats controversy on radionuclide soil action levels

International Nuclear Information System (INIS)

Earle, T.C.

2004-01-01

This report describes the Rocky Flats radionuclide soil action level controversy as a case study for the purpose of understanding the nature and value of stakeholder involvement in the management of radiological hazards. The report consists of three main sections. The first section outlines the Rocky Flats story, including the Cold War era, the post-Cold War era, and the transition between the two. This provides the context necessary to understand the radionuclide soil action level controversy, the main events of which are described in the second section. In the final section, the Rocky Flats case is briefly discussed within the framework of a general model of stakeholder involvement and the lessons learned from the case are identified. (author)

Concentration-driven models revisited: towards a unified framework to model settling tanks in water resource recovery facilities.

Science.gov (United States)

Torfs, Elena; Martí, M Carmen; Locatelli, Florent; Balemans, Sophie; Bürger, Raimund; Diehl, Stefan; Laurent, Julien; Vanrolleghem, Peter A; François, Pierre; Nopens, Ingmar

2017-02-01

A new perspective on the modelling of settling behaviour in water resource recovery facilities is introduced. The ultimate goal is to describe in a unified way the processes taking place both in primary settling tanks (PSTs) and secondary settling tanks (SSTs) for a more detailed operation and control. First, experimental evidence is provided, pointing out distributed particle properties (such as size, shape, density, porosity, and flocculation state) as an important common source of distributed settling behaviour in different settling unit processes and throughout different settling regimes (discrete, hindered and compression settling). Subsequently, a unified model framework that considers several particle classes is proposed in order to describe distributions in settling behaviour as well as the effect of variations in particle properties on the settling process. The result is a set of partial differential equations (PDEs) that are valid from dilute concentrations, where they correspond to discrete settling, to concentrated suspensions, where they correspond to compression settling. Consequently, these PDEs model both PSTs and SSTs.

Rocky Mountain spotted fever from an unexpected tick vector in Arizona.

Science.gov (United States)

Demma, Linda J; Traeger, Marc S; Nicholson, William L; Paddock, Christopher D; Blau, Dianna M; Eremeeva, Marina E; Dasch, Gregory A; Levin, Michael L; Singleton, Joseph; Zaki, Sherif R; Cheek, James E; Swerdlow, David L; McQuiston, Jennifer H

2005-08-11

Rocky Mountain spotted fever is a life-threatening, tick-borne disease caused by Rickettsia rickettsii. This disease is rarely reported in Arizona, and the principal vectors, Dermacentor species ticks, are uncommon in the state. From 2002 through 2004, a focus of Rocky Mountain spotted fever was investigated in rural eastern Arizona. We obtained blood and tissue specimens from patients with suspected Rocky Mountain spotted fever and ticks from patients' homesites. Serologic, molecular, immunohistochemical, and culture assays were performed to identify the causative agent. On the basis of specific laboratory criteria, patients were classified as having confirmed or probable Rocky Mountain spotted fever infection. A total of 16 patients with Rocky Mountain spotted fever infection (11 with confirmed and 5 with probable infection) were identified. Of these patients, 13 (81 percent) were children 12 years of age or younger, 15 (94 percent) were hospitalized, and 2 (12 percent) died. Dense populations of Rhipicephalus sanguineus ticks were found on dogs and in the yards of patients' homesites. All patients with confirmed Rocky Mountain spotted fever had contact with tick-infested dogs, and four had a reported history of tick bite preceding the illness. R. rickettsii DNA was detected in nonengorged R. sanguineus ticks collected at one home, and R. rickettsii isolates were cultured from these ticks. This investigation documents the presence of Rocky Mountain spotted fever in eastern Arizona, with common brown dog ticks (R. sanguineus) implicated as a vector of R. rickettsii. The broad distribution of this common tick raises concern about its potential to transmit R. rickettsii in other settings. Copyright 2005 Massachusetts Medical Society.

Numerical Modelling and Measurement in a Test Secondary Settling Tank

DEFF Research Database (Denmark)

Dahl, C.; Larsen, Torben; Petersen, O.

1994-01-01

sludge. Phenomena as free and hindered settling and the Bingham plastic characteristic of activated sludge suspensions are included in the numerical model. Further characterisation and test tank experiments are described. The characterisation experiments were designed to measure calibration parameters...... for model description of settling and density differences. In the test tank experiments, flow velocities and suspended sludge concentrations were measured with different tank inlet geomotry and hydraulic and sludge loads. The test tank experiments provided results for the calibration of the numerical model......A numerical model and measurements of flow and settling in activated sludge suspension is presented. The numerical model is an attempt to describe the complex and interrelated hydraulic and sedimentation phenomena by describing the turbulent flow field and the transport/dispersion of suspended...

Ongoing Cerebral Vasculitis During Treatment of Rocky Mountain Spotted Fever.

Science.gov (United States)

Sun, Lisa R; Huisman, Thierry A G M; Yeshokumar, Anusha K; Johnston, Michael V

2015-11-01

Rocky Mountain spotted fever is a tickborne infection that produces a systemic small-vessel vasculitis; its prognosis is excellent if appropriate treatment is initiated early. Because the advent of effective antirickettsial therapies predates the widespread use of brain magnetic resonance imaging, there are limited data on the effect of untreated Rocky Mountain spotted fever infection on neuroimaging studies. We describe a 7-year-old girl with delayed treatment of Rocky Mountain spotted fever who suffered severe neurological impairment. Serial brain magnetic resonance images revealed a progressive "starry sky appearance," which is proposed to result from the same small vessel vasculitis that causes the characteristic skin rash of this infection. Neurological injury can continue to occur despite specific antirickettsial therapy in Rocky Mountain spotted fever. This child's clinical features raise questions about the optimal management of this infection, particularly the utility of immune modulating therapies in cases of delayed treatment and neurological involvement. Copyright © 2015 Elsevier Inc. All rights reserved.

Disposal of sediments from the 1300-N Emergency Dump Basin

International Nuclear Information System (INIS)

Keen, R.; Duncan, G.M.

1996-01-01

This report describes the characterization of the 1300-N Emergency Dump Basin (EDB) sediments, summarizes the data obtained, the resultant waste categorization, and the preferred disposal method. The EDB is an outdoor, concrete storage pond with a 3/16-in. carbon steel liner. The basin (completed in 1963) originally served as a quenching pool for reactor blowdown in the event of a primary coolant leak. Later, the basin received blowdown from the N Reactor steam generators. The steam generator blowdowns and leading isolation valves allowed radioactively contaminated water (from primary and secondary reactor coolant leaks) to enter the basin. Windblown dust and sand have settled in the basin over the years (because of its outdoor location), causing the present layer of sediments. To minimize potential airborne contamination, the water level was kept constant by adding water. However, the addition of water was stopped to minimize the amount of contaminated water needing disposal. To ensure that the surfaces exposed as a result of evaporation pose no immediate airborne contaminant problem, the contamination levels are monitored by Radiation Control Technicians. As part of the deactivation of N Reactor facilities, the EDB will be stabilized for long-term surveillance and maintenance prior to final decontamination and demolition

Estimation of settling velocity of sediment particles in estuarine and coastal waters

Science.gov (United States)

Nasiha, Hussain J.; Shanmugam, Palanisamy

2018-04-01

A model for estimating the settling velocity of sediment particles (spherical and non-spherical) in estuarine and coastal waters is developed and validated using experimental data. The model combines the physical, optical and hydrodynamic properties of the particles and medium to estimate the sediment settling velocity. The well-known Stokes law is broadened to account for the influencing factors of settling velocity such as particle size, shape and density. To derive the model parameters, laboratory experiments were conducted using natural flaky seashells, spherical beach sands and ball-milled seashell powders. Spectral light backscattering measurements of settling particles in a water tank were made showing a distinct optical feature with a peak shifting from 470-490 nm to 500-520 nm for particle populations from spherical to flaky grains. This significant optical feature was used as a proxy to make a shape determination in the present model. Other parameters experimentally determined included specific gravity (ΔSG) , Corey shape factor (CSF) , median grain diameter (D50) , drag coefficient (Cd) and Reynolds number (Re) . The CSF values considered ranged from 0.2 for flaky to 1.0 for perfectly spherical grains and Reynolds numbers from 2.0 to 105 for the laminar to turbulent flow regimes. The specific gravity of submerged particles was optically derived and used along with these parameters to estimate the sediment settling velocity. Comparison with the experiment data showed that the present model estimated settling velocities of spherical and non-spherical particles that were closely consistent with the measured values. Findings revealed that for a given D50, the flaky particles caused a greater decrease in settling velocity than the spherical particles which suggests that the particle shape factor has a profound role in influencing the sediment settling velocity and drag coefficients, especially in transitional and turbulent flow regimes. The present model can

Food Poverty Profile in Settled Pastrol Households of Lowland Marsabit: Evidence from Micro Data

International Nuclear Information System (INIS)

Nyamori, B.

2002-01-01

Frequent and severe droughts experienced in ASALs push pastoralists out of the traditional livestock monoculture, which together with the growing human population lead to increasing settlement. Unlike nomads who access traditional livestock foods at all times, settled households have limited access, which does not guarantee their food security. To achieve the food security the settled households supplement limited livestock foods with market foods. High demand for market foods increases demand for money and since pastoral communities have limited income-generating opportunities, many households are relegated to below food poverty line. Most studies on food security in ASALs focus on livestock productivity without considering that settled households depend, to a small extent, on livestock foods. Since settled households experience a lot of socio-economic changes,their food security status needs to be appropriately evaluated. The aim of this study t is to establish the food poverty profile of the settled households and recommend appropriate measures for attaining food security in the settled households

Accumulation of Settling Particles in Some Coral Reef Areas of Peninsular Malaysia

International Nuclear Information System (INIS)

Lee, J.N.; Che Abdul Rahim Mohamed

2011-01-01

The aim of this study was to determine the accumulation of settling particles in coral reefs of Peninsular Malaysia. Settling particles were collected from the coral reefs of Port Dickson, Pulau Langkawi, Pulau Tioman, Pulau Redang and Pulau Tinggi from 2005 to 2008. The average total settling particles in Pulau Langkawi and Port Dickson was 49.8 mg/ cm 2 / day, while for Pulau Tioman, Pulau Redang, and Pulau Tinggi was 3.5 mg/ cm 2 / day. The results showed that accumulations rate in west coast were higher than east coast of Peninsular Malaysia. However, Pulau Tioman in the east coast received high accumulations rate of settling particles in certain times of the year due to sediment resuspension at shallow reefs caused by high energy seasonal yearly wave and monsoon. (author)

45 CFR 2554.48 - Can the administrative complaint be settled voluntarily?

Science.gov (United States)

2010-10-01

... 45 Public Welfare 4 2010-10-01 2010-10-01 false Can the administrative complaint be settled voluntarily? 2554.48 Section 2554.48 Public Welfare Regulations Relating to Public Welfare (Continued... Appeals § 2554.48 Can the administrative complaint be settled voluntarily? (a) Parties may make offers of...

Biological impacts of oil pollution: rocky shores. V. 7

International Nuclear Information System (INIS)

1997-01-01

Most people with access to the sea have at one time enjoyed looking into rockpools and searching for crabs under boulders. Rocky shores have a great deal of fascination for people and they are the closest that many of them will get to the mysteries below the low tide mark. They are found, in some form, on most of the world's coasts and their ecology has been the subject of many books, reports and scientific papers. Rocky shores encompass a variety of intertidal habitats and have a range of vulnerabilities to oil. While some areas are quickly and easily cleaned by natural forces others can trap oil in sensitive sub-habitats which may then be damaged and take many years to recover. Furthermore, rocky shores have an importance in the wider context of marine ecosystems and some provide important local fisheries resources, tourism and amenities. This report describes the factors that make some rocky shores more sensitive to oil spills than others and considers the most appropriate methods of clean-up. Case histories are used to illustrate the effects of spills and spill clean-up, as well as typical recovery rates. (UK)

Characterization of the variability of settling in wastewater treatment

International Nuclear Information System (INIS)

Cherif, Hayet; Touhami, Youssef; Shayeb, Hedi

2009-01-01

The processes of biological treatment of wastewater in activated sludge are complex dynamic processes are difficult to manage. The ability of the sludge settling is a key parameter for the overall effectiveness of pollution control process and for preserving the quality of the receiving environment. So for better management of wastewater treatment plants, a study of interactions between the couple reactor clarifier is necessary. A new management technique must notify the operator to problems related to sludge mainly to the loss of the sludge blanket which will have adverse effects on the environment. The approach is widely adopted and applied an approach aims to identify factors that may explain the observed phenomena in order to draw strategies that could improve the sludge settling on an industrial scale. The widely used approach is based on measuring Mohlman index and gives an impression, on the ability of the mud settling, but does not prevent the operator to anomalies that have places in the decanter.

Numerical Investigation of Effects of Inlet Placement and Characteristics of Baffles in Settling Tanks

Directory of Open Access Journals (Sweden)

Hamid Shamloo

2012-12-01

Full Text Available Settling tanks are one of the main parts of treatment plants and different parameters are effective in the settling tank performance. In this study effects of some of these parameters such as the situation of the inlet opening as well as the existence and position of baffles in the tanks are investigated.  2D numerical simulations of primary settling tanks are carried out using 2D Fluent software and the best position for the  inlet to enhance  the  their performance found  to be in the middle of the tank  with optimum size  of the baffle about 30% the height of settling tank  at a distance about 5-10% settling tank's length.

Geology and coal-bed methane resources of the northern San Juan Basin, Colorado and New Mexico

International Nuclear Information System (INIS)

Fassett, J.E.

1988-01-01

This guidebook is the first of its kind: A focused look at coal-bed methane in a large Rocky Mountain Laramide basin. The papers in this volume cover every aspect of coal-bed methane in the San Juan Basin, including: The geology, environments of deposition, and geometry of the coal beds that contain the resource; the origin and migration history of the gas; basin-wide resource estimates; the engineering aspects of getting the gas out of the ground; the marketing and economics of producing coal-bed methane in the San Juan Basin; the legal ownership of the gas; state regulations governing well spacing and field rules; disposal of produced water; and land and mineral ownership patterns in the northern part of the basin. Also included are detailed papers on all of the major coal-bed methane fields in the basin, and in a paper on the history of Fruitland gas production, a discussion of most of the not-so-major fields. A small section of the book deals with geophysical methods, as yet still experimental, for surface detection of underground hydrocarbon resources. Individual papers have been processed separately for inclusion on the data base

Tectonic isolation from regional sediment sourcing of the Paradox Basin

Science.gov (United States)

Smith, T. M.; Saylor, J.; Sundell, K. E.; Lapen, T. J.

2017-12-01

The Appalachian and Ouachita-Marathon mountain ranges were created by a series of tectonic collisions that occurred through the middle and late Paleozoic along North America's eastern and southern margins, respectively. Previous work employing detrital zircon U-Pb geochronology has demonstrated that fluvial and eolian systems transported Appalachian-derived sediment across the continent to North America's Paleozoic western margin. However, contemporaneous intraplate deformation of the Ancestral Rocky Mountains (ARM) compartmentalized much of the North American western interior and mid-continent. We employ lithofacies characterization, stratigraphic thickness, paleocurrent data, sandstone petrography, and detrital zircon U-Pb geochronology to evaluate source-sink relationships of the Paradox Basin, which is one of the most prominent ARM basins. Evaluation of provenance is conducted through quantitative comparison of detrital zircon U-Pb distributions from basin samples and potential sources via detrital zircon mixture modeling, and is augmented with sandstone petrography. Mixing model results provide a measure of individual source contributions to basin stratigraphy, and are combined with outcrop and subsurface data (e.g., stratigraphic thickness and facies distributions) to create tectonic isolation maps. These maps elucidate drainage networks and the degree to which local versus regional sources influence sediment character within a single basin, or multiple depocenters. Results show that despite the cross-continental ubiquity of Appalachian-derived sediment, fluvial and deltaic systems throughout much of the Paradox Basin do not record their influence. Instead, sediment sourcing from the Uncompahgre Uplift, which has been interpreted to drive tectonic subsidence and formation of the Paradox Basin, completely dominated its sedimentary record. Further, the strong degree of tectonic isolation experienced by the Paradox Basin appears to be an emerging, yet common

Development of a new model for batch sedimentation and application to secondary settling tanks design.

Science.gov (United States)

Karamisheva, Ralica D; Islam, M A

2005-01-01

Assuming that settling takes place in two zones (a constant rate zone and a variable rate zone), a model using four parameters accounting for the nature of the water-suspension system has been proposed for describing batch sedimentation processes. The sludge volume index (SVI) has been expressed in terms of these parameters. Some disadvantages of the SVI application as a design parameter have been pointed out, and it has been shown that a relationship between zone settling velocity and sludge concentration is more consistent for describing the settling behavior and for design of settling tanks. The permissible overflow rate has been related to the technological parameters of secondary settling tank by simple working equations. The graphical representations of these equations could be used to optimize the design and operation of secondary settling tanks.

Investigating the settling dynamics of cohesive silt particles with particle-resolving simulations

Science.gov (United States)

Sun, Rui; Xiao, Heng; Sun, Honglei

2018-01-01

The settling of cohesive sediment is ubiquitous in aquatic environments, and the study of the settling process is important for both engineering and environmental reasons. In the settling process, the silt particles show behaviors that are different from non-cohesive particles due to the influence of inter-particle cohesive force. For instance, the flocs formed in the settling process of cohesive silt can loosen the packing, and thus the structural densities of cohesive silt beds are much smaller than that of non-cohesive sand beds. While there is a consensus that cohesive behaviors depend on the characteristics of sediment particles (e.g., Bond number, particle size distribution), little is known about the exact influence of these characteristics on the cohesive behaviors. In addition, since the cohesive behaviors of the silt are caused by the inter-particle cohesive forces, the motions of and the contacts among silt particles should be resolved to study these cohesive behaviors in the settling process. However, studies of the cohesive behaviors of silt particles in the settling process based on particle-resolving approach are still lacking. In the present work, three-dimensional settling process is investigated numerically by using CFD-DEM (Computational Fluid Dynamics-Discrete Element Method). The inter-particle collision force, the van der Waals force, and the fluid-particle interaction forces are considered. The numerical model is used to simulate the hindered settling process of silt based on the experimental setup in the literature. The results obtained in the simulations, including the structural densities of the beds, the characteristic lines, and the particle terminal velocity, are in good agreement with the experimental observations in the literature. To the authors' knowledge, this is the first time that the influences of non-dimensional Bond number and particle polydispersity on the structural densities of silt beds have been investigated separately

The Effect of Low Energy Turbulence in Estuary Margins on Fine Sediment Settling

Science.gov (United States)

Allen, R. M.; MacVean, L. J.; Tse, I.; Mazzaro, L. J.; Stacey, M. T.; Variano, E. A.

2014-12-01

Sediment dynamics in estuaries and near shore regions control the growth or erosion of the bed and fringing wetlands, determine the spread of sediment-associated contaminants, and limit the light availability for primary productivity through turbidity. In estuaries such as San Francisco Bay, this sediment is often cohesive, and can flocculate. Changes to the composition of the sediment and waters, the suspended sediment concentration, and the turbulence can all affect the flocculation of suspended sediment. In turn, flocculation controls the particle diameter, settling velocity, density, and particle inertia. These sediment properties drive the turbulent diffusivity, which balances with the settling velocity to impact the vertical distribution of sediment in the water column. The vertical profile strongly affects how sediment is transported through the estuary by lateral flow. Turbulence may also impact settling velocity in non-cohesive particles. In turbulence, dense particles may get trapped in convergent flow regions, thus particles are more likely to get swept along the downward side of a turbulent eddy than the upward side, resulting in enhanced settling velocities. We isolated the impacts of turbulence level, particle size and type, and suspended sediment concentration on particle settling velocities using uniform grain size particles in homogeneous isotropic turbulence. Controlling the turbulence in a well-defined turbulence tank, we used Two Acoustic Doppler Velocimeters, separated vertically, to measure turbulent velocities (w') and suspended sediment concentrations (C), which yield condition dependent settling velocities (ws), via equation 1. Lab characterization of particle settling velocities help to validate the method for measuring settling velocities in the field, and will serve as a foundation for an extensive field experiment in San Francisco Bay. Characterizing the velocity enhancement relative to the Stokes number, the Rouse number, and the

Convection and crystal settling in sills

Science.gov (United States)

Gibb, Fergus G. F.; Henderson, C. Michael B.

1992-02-01

It has been advocated that convective and crystal settling processes play significant, and perhaps crucial, roles in magmatic differentiation. The fluid dynamics of magma chambers have been extensively studied in recent years, both theoretically and experimentally, but there is disagreement over the nature and scale of the convection, over its bearing on fractionation and possibly over whether it occurs at all. The differential distribution of modal olivine with height in differentiated alkaline basic sills provides critical evidence to resolve this controversy, at least for small to medium-large magma chambers. Our own and others' published data for such sills show that, irrespective of overall olivine content, modal olivine contents tend to increase in a roughly symmetrical manner inwards from the upper and lower margins of the sill, i.e. the distribution patterns are more often approximately D-shaped rather than the classic S-shape generally ascribed to gravity settling. We concur with the majority of other authors that this is an original feature of the filling process which has survived more or less unchanged since emplacement. We therefore conclude that the magmas have not undergone turbulent convection and that gravity settling has usually played only a minor modifying role since the intrusion of these sills. We offer a possible explanation for the apparent contradiction between fluid dynamical theory and the petrological evidence by suggesting that such sills rarely fill by the rapid injection of a single pulse of magma. Rather, they form from a series of pulses or a continuous pulsed influx over a protracted interval during which marginal cooling severely limits the potential for thermal convection.

Project Management Plan 105-KE Basin sludge retrieval and packaging

International Nuclear Information System (INIS)

McWethy, L.M.

1994-01-01

The KE Basin contains over 1,100 metric tons of spent nuclear fuel (SNF). The bulk of this inventory consists of over 50,000 zircaloy clad, uranium metal N-Reactor fuel element assemblies, along with less than half a metric ton of single-pass reactor fuel elements, stored in over 3,600 open top canister assemblies. In addition, sludge containing fissile and fission product material from damaged/degraded fuel has accumulated in the basin. The sludge, particularly the fines, impacts basin operations by clouding the water and making activities requiring a clear view impossible to complete until after sludge settles. Packaging would get the sludge out of the operator's way and allow it to be moved within the basin in a more manageable state. The primary project objective is to develop, procure, and quality the equipment needed to remove all sludge from the KE Basin with minimal dose commitment, minimal cost, and on schedule. The project will provide: (1) the development, testing, and installation of equipment for sludge retrieval and packaging; (2) understanding of and experience with actual sludge through near-term sludge packaging feature tests in the KE Basin; (3) sludge removal and handling equipment required to support debris removal, fuel handling, and other activities involving sludge within the KE Basin; and (4) enlist industry expertise in all phases of the project. This Project Management Plant establishes the organizational responsibilities, control systems, and procedures for the execution of project activities for KE Basin sludge retrieval packaging, to meet programmatic requirements within authorized funding and approved schedules

Determination of Settling Tanks Performance Using an Eulerian- Lagrangian Method

OpenAIRE

A Tamayol; B Firoozabadi; G Ahmadi

2008-01-01

Circulation regions always exist in settling tanks. These regions reduce the tank’s performance and decrease its effective volume. The recirculation zones would result in short-circuiting and high flow mixing problems. The inlet position would also affect the size and location of the recirculation region. Using a proper baffle configuration could substantially increase the performance of the settling tanks. A common procedure for the comparison of the performances of diffe...

THERMODYNAMIC LIMITS ON MAGNETODYNAMOS IN ROCKY EXOPLANETS

International Nuclear Information System (INIS)

Gaidos, Eric; Conrad, Clinton P.; Manga, Michael; Hernlund, John

2010-01-01

To ascertain whether magnetic dynamos operate in rocky exoplanets more massive or hotter than the Earth, we developed a parametric model of a differentiated rocky planet and its thermal evolution. Our model reproduces the established properties of Earth's interior and magnetic field at the present time. When applied to Venus, assuming that planet lacks plate tectonics and has a dehydrated mantle with an elevated viscosity, the model shows that the dynamo shuts down or never operated. Our model predicts that at a fixed planet mass, dynamo history is sensitive to core size, but not to the initial inventory of long-lived, heat-producing radionuclides. It predicts that rocky planets larger than 2.5 Earth masses will not develop inner cores because the temperature-pressure slope of the iron solidus becomes flatter than that of the core adiabat. Instead, iron 'snow' will condense near or at the top of these cores, and the net transfer of latent heat upward will suppress convection and a dynamo. More massive planets can have anemic dynamos due to core cooling, but only if they have mobile lids (plate tectonics). The lifetime of these dynamos is shorter with increasing planet mass but longer with higher surface temperature. Massive Venus-like planets with stagnant lids and more viscous mantles will lack dynamos altogether. We identify two alternative sources of magnetic fields on rocky planets: eddy currents induced in the hot or molten upper layers of planets on very short-period orbits, and dynamos in the ionic conducting layers of 'ocean' planets with ∼10% mass in an upper mantle of water (ice).

Issues evaluation process at Rocky Flats Plant

International Nuclear Information System (INIS)

Smith, L.C.

1992-01-01

This report describes the issues evaluation process for Rocky Flats Plant as established in July 1990. The issues evaluation process was initiated February 27, 1990 with a Charter and Process Overview for short-term implementation. The purpose of the process was to determine the projects required for completion before the Phased Resumption of Plutonium Operations. To determine which projects were required, the issues evaluation process and emphasized risk mitigation, based on a ranking system. The purpose of this report is to document the early design of the issues evaluation process to record the methodologies used that continue as the basis for the ongoing Issues Management Program at Rocky Flats Plant

[Relationships between landscape structure and rocky desertification in karst region of northwestern Guangxi].

Science.gov (United States)

Zhang, Xiao-nan; Wang, Ke-lin; Chen, Hong-song; Zhang, Wei

2008-11-01

By using canonical correspondence analysis (CCA), sixteen landscape indices were adopted to quantitatively analyze the relationships between the landscape structure and rocky desertification in karst region of Huanjiang County, Guangxi Province. The results showed that the first and the second ordination axis of CCA were strongly correlated to the factors of average patch area, average dry land patch area, landscape shape index, and landscape aggregation index. The potential rocky desertification in the region was highly positively correlated with the average dry land patch area and the average fractal dimensions of dry land and shrub land, but negatively correlated with the patch numbers of dry land. Light rocky desertification had obvious positive correlations with the fractal dimension index, average fractal dimension of unused land, and patch numbers of shrub land; while moderate and strong rocky desertification had high positive correlations with the average unused land patch area but negative correlation with the average fractal dimension of shrub land. To some extent, rocky desertification degree might be represented by the values of landscape indices. The gradient variation in karst rocky desertification along landscape structure was clearly presented by the results of CCA.

Segregation and differential settling in flocculated tailings

Energy Technology Data Exchange (ETDEWEB)

Farinato, R.S.; Mahmoudkhani, A.; Fenderson, T.; Watson, P. [Kemira, Atlanta, GA (United States)

2010-07-01

Untreated oil sands tailings have a high solids content, have poor dewaterability, and contain no aggregates. This PowerPoint presentation investigated segregation and differential settling in flocculated tailings. Tailings were treated with gypsum and various polymers. Cylinder settling, dynamic rheometry, particle size analysis, and microscopy techniques were used to characterize the composite tailings. The particles sizes of the samples were evaluated in relation to shear rate, bed depth, and treatment. The study showed that the gypsum-treated tailings had small aggregates, size stratification, a high solids content, and poor dewaterability. The polymer N-treated tailings had the lowest solids content, good dewaterability, and weak aggregates. The polymer A-treated tailings had a low solids content, very good dewaterability, and strong aggregates. The addition of a coagulant to the polymer-A treated tailings provided weaker aggregates and a higher solids content. tabs., figs.

Geodesic Monitoring of Settling in Vertical Fuel Tanks

Directory of Open Access Journals (Sweden)

Luis Enrique Acosta-González

2017-07-01

Full Text Available The behavior of the settling in a vertical tank used for fuel storage was studied. Monitoring was conducted using the geodesic model for the geometric leveling of high accuracy category II. The original project varied during construction by replacing deep foundations with a surface one applying compaction techniques to improve soil resistance. The deformation values obtained provided valuable information on the implementation of the proposed foundation alternative depending on time and loads. The maximum settling was reported to be 132,6 mm. The displacements in the control points located in the perimeter of the tank had a distinct nature with a maximum of 44,2 mm, which caused the foundation structure to crack.

Closing Rocky Flats by 2006

International Nuclear Information System (INIS)

Tuor, N. R.; Schubert, A. L.

2002-01-01

Safely accelerating the closure of Rocky Flats to 2006 is a goal shared by many: the State of Colorado, the communities surrounding the site, the U.S. Congress, the Department of Energy, Kaiser-Hill and its team of subcontractors, the site's employees, and taxpayers across the country. On June 30, 2000, Kaiser-Hill (KH) submitted to the Department of Energy (DOE), KH's plan to achieve closure of Rocky Flats by December 15, 2006, for a remaining cost of $3.96 billion (February 1, 2000, to December 15, 2006). The Closure Project Baseline (CPB) is the detailed project plan for accomplishing this ambitious closure goal. This paper will provide a status report on the progress being made toward the closure goal. This paper will: provide a summary of the closure contract completion criteria; give the current cost and schedule variance of the project and the status of key activities; detail important accomplishments of the past year; and discuss the challenges ahead

Rocky Flats cleanup receives new deadline

International Nuclear Information System (INIS)

Anon.

1993-01-01

The Rocky Flats nuclear weapon plant near Denver narrowly missed a court-ordered shutdown of virtually all cleanup activities when it failed to meet an Aug. 22 deadline for a state permit to store mixed radioactive and hazardous wastes on site. US District Court Judge Lewis Babcock granted a 90-day stay of contempt charges against the US Dept. of Energy, but left open the possibility of civil penalties under the Resource Conservation and Recovery Act. DOE's problems stem from a lawsuit the Sierra Club won two years ago in which Babcock gave Rocky Flats until Aug. 22 to obtain a RCRA permit or interim status from Colorado to store 600 cu yd of mixed wastes. If DOE failed to do so, the court said it could not generate further hazardous wastes at the site

Leachability of solidified (Ba,Ra)SO/sub 4/ sediments in simulated settling ponds

International Nuclear Information System (INIS)

Constable, T.W.; Snodgrass, W.J.

1988-01-01

The decanted effluent from uranium tailings basins contains large amounts of dissolved Ra-226. To remove this Ra-226, the effluent is treated with barium chloride (BaCl/sub 2/) to precipitate barium-radium sulphate -(Ba,Ra)SO/sub 4/]. The sediments are stored on the bottom of the treatment pond and the treated effluent is discharged to a local water course. However, redissolution of Ra-226 fro these sediments may occur after the tailings area has been abandoned and thus cause contamination of receiving waters. This study was conducted to investigate the rate at which this dissolution occurred and to determine if this rate could be decreased by solidification of the sediments. Solidification (also referred to as chemical fixation or encapsulation) involves mixing the sediments with chemicals to produce a solid matrix analogous to concrete. The sediments used in the study were dredged in 1976 from the bottom of the North Nordic Lake settling pond in Elliot Lake, Ontario, which receives the effluent from the Nordic tailings area

Turbulent particle transport in streams: can exponential settling be reconciled with fluid mechanics?

Science.gov (United States)

McNair, James N; Newbold, J Denis

2012-05-07

Most ecological studies of particle transport in streams that focus on fine particulate organic matter or benthic invertebrates use the Exponential Settling Model (ESM) to characterize the longitudinal pattern of particle settling on the bed. The ESM predicts that if particles are released into a stream, the proportion that have not yet settled will decline exponentially with transport time or distance and will be independent of the release elevation above the bed. To date, no credible basis in fluid mechanics has been established for this model, nor has it been rigorously tested against more-mechanistic alternative models. One alternative is the Local Exchange Model (LEM), which is a stochastic advection-diffusion model that includes both longitudinal and vertical spatial dimensions and is based on classical fluid mechanics. The LEM predicts that particle settling will be non-exponential in the near field but will become exponential in the far field, providing a new theoretical justification for far-field exponential settling that is based on plausible fluid mechanics. We review properties of the ESM and LEM and compare these with available empirical evidence. Most evidence supports the prediction of both models that settling will be exponential in the far field but contradicts the ESM's prediction that a single exponential distribution will hold for all transport times and distances. Copyright © 2012 Elsevier Ltd. All rights reserved.

Research advances and challenges in one-dimensional modeling of secondary settling tanks--a critical review.

Science.gov (United States)

Li, Ben; Stenstrom, M K

2014-11-15

Sedimentation is one of the most important processes that determine the performance of the activated sludge process (ASP), and secondary settling tanks (SSTs) have been frequently investigated with the mathematical models for design and operation optimization. Nevertheless their performance is often far from satisfactory. The starting point of this paper is a review of the development of settling theory, focusing on batch settling and the development of flux theory, since they played an important role in the early stage of SST investigation. The second part is an explicit review of the established 1-D SST models, including the relevant physical law, various settling behaviors (hindered, transient, and compression settling), the constitutive functions, and their advantages and disadvantages. The third part is a discussion of numerical techniques required to solve the governing equation, which is usually a partial differential equation. Finally, the most important modeling challenges, such as settleability description, settling behavior understanding, are presented. Copyright © 2014 Elsevier Ltd. All rights reserved.

Microthrix parvicella abundance associates with activated sludge settling velocity and rheology - Quantifying and modelling filamentous bulking.

Science.gov (United States)

Wágner, Dorottya S; Ramin, Elham; Szabo, Peter; Dechesne, Arnaud; Plósz, Benedek Gy

2015-07-01

The objective of this work is to identify relevant settling velocity and rheology model parameters and to assess the underlying filamentous microbial community characteristics that can influence the solids mixing and transport in secondary settling tanks. Parameter values for hindered, transient and compression settling velocity functions were estimated by carrying out biweekly batch settling tests using a novel column setup through a four-month long measurement campaign. To estimate viscosity model parameters, rheological experiments were carried out on the same sludge sample using a rotational viscometer. Quantitative fluorescence in-situ hybridisation (qFISH) analysis, targeting Microthrix parvicella and phylum Chloroflexi, was used. This study finds that M. parvicella - predominantly residing inside the microbial flocs in our samples - can significantly influence secondary settling through altering the hindered settling velocity and yield stress parameter. Strikingly, this is not the case for Chloroflexi, occurring in more than double the abundance of M. parvicella, and forming filaments primarily protruding from the flocs. The transient and compression settling parameters show a comparably high variability, and no significant association with filamentous abundance. A two-dimensional, axi-symmetrical computational fluid dynamics (CFD) model was used to assess calibration scenarios to model filamentous bulking. Our results suggest that model predictions can significantly benefit from explicitly accounting for filamentous bulking by calibrating the hindered settling velocity function. Furthermore, accounting for the transient and compression settling velocity in the computational domain is crucial to improve model accuracy when modelling filamentous bulking. However, the case-specific calibration of transient and compression settling parameters as well as yield stress is not necessary, and an average parameter set - obtained under bulking and good settling

Runoff of small rocky headwater catchments: Field observations and hydrological modeling

Science.gov (United States)

Gregoretti, C.; Degetto, M.; Bernard, M.; Crucil, G.; Pimazzoni, A.; De Vido, G.; Berti, M.; Simoni, A.; Lanzoni, S.

2016-10-01

In dolomitic headwater catchments, intense rainstorms of short duration produce runoff discharges that often trigger debris flows on the scree slopes at the base of rock cliffs. In order to measure these discharges, we placed a measuring facility at the outlet (elevation 1770 m a.s.l.) of a small, rocky headwater catchment (area ˜0.032 km2, average slope ˜320%) located in the Venetian Dolomites (North Eastern Italian Alps). The facility consists of an approximately rectangular basin, ending with a sharp-crested weir. Six runoff events were recorded in the period 2011-2014, providing a unique opportunity for characterizing the hydrological response of the catchment. The measured hydrographs display impulsive shapes, with an abrupt raise up to the peak, followed by a rapidly decreasing tail, until a nearly constant plateau is eventually reached. This behavior can be simulated by means of a distributed hydrological model if the excess rainfall is determined accurately. We show that using the Soil Conservation Service Curve-Number (SCS-CN) method and assuming a constant routing velocity invariably results in an underestimated peak flow and a delayed peak time. A satisfactory prediction of the impulsive hydrograph shape, including peak value and timing, is obtained only by combining the SCS-CN procedure with a simplified version of the Horton equation, and simulating runoff routing along the channel network through a matched diffusivity kinematic wave model. The robustness of the proposed methodology is tested through a comparison between simulated and observed timings of runoff or debris flow occurrence in two neighboring alpine basins.

The impact of the adult blue mussel (Mytilus edulis) population on settling of conspecific larvae

DEFF Research Database (Denmark)

Dolmer, Per; Stenalt, Ea

2010-01-01

The choice of a mussel bed as a settling locality by conspecific mussel larvae is a trade-off between reduced fitness due to an increased risk of larval predation and post-settling food competition with the filtering adults and the benefit from a reduced post-settling mortality. This reduced post...

Competing jurisdictions : settling land claims in Africa

NARCIS (Netherlands)

Evers, S.; Spierenburg, M.; Wels, H.

2005-01-01

The papers included in this volume were earlier presented at a conference on the settlement of land claims in Africa, which was held in Amsterdam in September 2003. The papers are written primarily from an anthropological perspective. Contributions: Introduction: competing jurisdictions: settling

Release fractions for Rocky Flats specific accidents

International Nuclear Information System (INIS)

Weiss, R.C.

1992-01-01

As Rocky Flats and other DOE facilities begin the transition process towards decommissioning, the nature of the scenarios to be studied in safety analysis will change. Whereas the previous emphasis in safety accidents related to production, now the emphasis is shifting to accidents related tc decommissioning and waste management. Accident scenarios of concern at Rocky Flats now include situations of a different nature and different scale than are represented by most of the existing experimental accident data. This presentation will discuss approaches at sign to use for applying the existing body of release fraction data to this new emphasis. Mention will also be made of ongoing efforts to produce new data and improve the understanding of physical mechanisms involved

Rocky Mountain spotted fever: a clinician's dilemma.

Science.gov (United States)

Masters, Edwin J; Olson, Gary S; Weiner, Scott J; Paddock, Christopher D

2003-04-14

Rocky Mountain spotted fever is still the most lethal tick-vectored illness in the United States. We examine the dilemmas facing the clinician who is evaluating the patient with possible Rocky Mountain spotted fever, with particular attention to the following 8 pitfalls in diagnosis and treatment: (1) waiting for a petechial rash to develop before diagnosis; (2) misdiagnosing as gastroenteritis; (3) discounting a diagnosis when there is no history of a tick bite; (4) using an inappropriate geographic exclusion; (5) using an inappropriate seasonal exclusion; (6) failing to treat on clinical suspicion; (7) failing to elicit an appropriate history; and (8) failing to treat with doxycycline. Early diagnosis and proper treatment save lives.

Idaho National Engineering Laboratory code assessment of the Rocky Flats transuranic waste

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-07-01

This report is an assessment of the content codes associated with transuranic waste shipped from the Rocky Flats Plant in Golden, Colorado, to INEL. The primary objective of this document is to characterize and describe the transuranic wastes shipped to INEL from Rocky Flats by item description code (IDC). This information will aid INEL in determining if the waste meets the waste acceptance criteria (WAC) of the Waste Isolation Pilot Plant (WIPP). The waste covered by this content code assessment was shipped from Rocky Flats between 1985 and 1989. These years coincide with the dates for information available in the Rocky Flats Solid Waste Information Management System (SWIMS). The majority of waste shipped during this time was certified to the existing WIPP WAC. This waste is referred to as precertified waste. Reassessment of these precertified waste containers is necessary because of changes in the WIPP WAC. To accomplish this assessment, the analytical and process knowledge available on the various IDCs used at Rocky Flats were evaluated. Rocky Flats sources for this information include employee interviews, SWIMS, Transuranic Waste Certification Program, Transuranic Waste Inspection Procedure, Backlog Waste Baseline Books, WIPP Experimental Waste Characterization Program (headspace analysis), and other related documents, procedures, and programs. Summaries are provided of: (a) certification information, (b) waste description, (c) generation source, (d) recovery method, (e) waste packaging and handling information, (f) container preparation information, (g) assay information, (h) inspection information, (i) analytical data, and (j) RCRA characterization.

Computational Fluid Dynamics Modelling of Hydraulics and Sedimentation in Process Reactors during Aeration Tank Settling

DEFF Research Database (Denmark)

Jensen, M.D.; Ingildsen, P.; Rasmussen, Michael R.

2006-01-01

Aeration tank settling is a control method allowing settling in the process tank during highhydraulic load. The control method is patented. Aeration tank settling has been applied in several wastewater treatment plants using the present design of the process tanks. Some process tank designs...... and outletcausing a disruption of the sludge blanket at the outlet and thereby reducing the retention of sludge in theprocess tank. The model has allowed us to establish a clear picture of the problems arising at the plantduring aeration tank settling. Secondly, several process tank design changes have been...

Coating degradation at tank bottomdue to settled water

International Nuclear Information System (INIS)

Majeed, U.; Rizvi, M.A.; Khan, I.H.

2008-01-01

In the present work, coating degradation as a result of settled water on fuel storage tank bottoms has been reported with the help of electrochemical impedance spectroscopy (EIS), blister analysis and gravimetric analysis (water uptake). Blistering occurs underneath the coating at the tank bottom due to direct contact with settled water. Degradation behavior of polyamide epoxy coatings on mild steel has been reported in term of coating resistance at the start of the experiments, after 96 hours and at the end of EIS experiments. Coating degradation in terms of shift in phase angle (theta) at high frequency as a function of exposure time has also been reported. The blister formation and gravimetric analysis data has also been reported in support of EIS result. (author)

Rheology Of Settled Solids In The Small Column Ion Exchange Process

International Nuclear Information System (INIS)

Poirier, M.; Ferguson, C.; Koopman, D.

2011-01-01

The Small Column Ion Exchange (SCIX) process is being developed to remove cesium, strontium, and actinides from Savannah River Site (SRS) Liquid Waste using an existing waste tank (i.e., Tank 41H) to house the process. This process adds monosodium titanate (MST) to a waste tank containing salt solution (and entrained sludge solids). While the process is operating, the solid particles will begin to settle at temperatures up to 45 C. Previous testing has shown that sludge-MST slurries that sit for extended periods (i.e., 1-61 days) at elevated temperatures (i.e., 23-80 C) can develop large shear strengths which could make them difficult to resuspend and remove from the tank. The authors are conducting rheological testing of mixtures containing various concentrations of sludge, MST, and crystalline silicotitanate (CST, ground and unground) that have been aged at different times (i.e., 0 to 13 weeks) and isothermally heated to 30, 45, or 60 C. Additional tests are being conducted that will allow the solid particles to settle at 45 C for 6, 12, and 24 months. The objectives of this task are to determine the impact of settling time and temperature on the shear strength, yield stress, and consistency of the slurries and to determine the impact of radiation on slurry rheology. The testing will determine the relative impact of these parameters rather than predict the shear strength, yield stress, and consistency as a function of feed and operating conditions. This document describes the rheology of slurries containing MST and simulated sludge that sat at elevated temperatures (i.e., up to 60 C) for up to 13 weeks. Rheology of CST-containing slurries, as well as results of the long term settling (6, 12, and 24 months) and irradiation tests (10 and 100 MRad), will be reported later. The conclusions from this analysis follow: (1) MST only slurries that sat at elevated temperatures had larger shear strength, yield stress, and consistency than MST plus sludge slurries that

RHEOLOGY OF SETTLED SOLIDS IN THE SMALL COLUMN ION EXCHANGE PROCESS

Energy Technology Data Exchange (ETDEWEB)

Poirier, M.; Ferguson, C.; Koopman, D.

2011-01-27

The Small Column Ion Exchange (SCIX) process is being developed to remove cesium, strontium, and actinides from Savannah River Site (SRS) Liquid Waste using an existing waste tank (i.e., Tank 41H) to house the process. This process adds monosodium titanate (MST) to a waste tank containing salt solution (and entrained sludge solids). While the process is operating, the solid particles will begin to settle at temperatures up to 45 C. Previous testing has shown that sludge-MST slurries that sit for extended periods (i.e., 1-61 days) at elevated temperatures (i.e., 23-80 C) can develop large shear strengths which could make them difficult to resuspend and remove from the tank. The authors are conducting rheological testing of mixtures containing various concentrations of sludge, MST, and crystalline silicotitanate (CST, ground and unground) that have been aged at different times (i.e., 0 to 13 weeks) and isothermally heated to 30, 45, or 60 C. Additional tests are being conducted that will allow the solid particles to settle at 45 C for 6, 12, and 24 months. The objectives of this task are to determine the impact of settling time and temperature on the shear strength, yield stress, and consistency of the slurries and to determine the impact of radiation on slurry rheology. The testing will determine the relative impact of these parameters rather than predict the shear strength, yield stress, and consistency as a function of feed and operating conditions. This document describes the rheology of slurries containing MST and simulated sludge that sat at elevated temperatures (i.e., up to 60 C) for up to 13 weeks. Rheology of CST-containing slurries, as well as results of the long term settling (6, 12, and 24 months) and irradiation tests (10 and 100 MRad), will be reported later. The conclusions from this analysis follow: (1) MST only slurries that sat at elevated temperatures had larger shear strength, yield stress, and consistency than MST plus sludge slurries that

Dynamic modeling of sludge compaction and consolidation processes in wastewater secondary settling tanks.

Science.gov (United States)

Abusam, A; Keesman, K J

2009-01-01

The double exponential settling model is the widely accepted model for wastewater secondary settling tanks. However, this model does not estimate accurately solids concentrations in the settler underflow stream, mainly because sludge compression and consolidation processes are not considered. In activated sludge systems, accurate estimation of the solids in the underflow stream will facilitate the calibration process and can lead to correct estimates of particularly kinetic parameters related to biomass growth. Using principles of compaction and consolidation, as in soil mechanics, a dynamic model of the sludge consolidation processes taking place in the secondary settling tanks is developed and incorporated to the commonly used double exponential settling model. The modified double exponential model is calibrated and validated using data obtained from a full-scale wastewater treatment plant. Good agreement between predicted and measured data confirmed the validity of the modified model.

Soil decontamination at Rocky Flats

International Nuclear Information System (INIS)

Olsen, R.L.; Hayden, J.A.; Alford, C.E.; Kochen, R.L.; Stevens, J.R.

1979-01-01

A soils decontamination project was initiated, to remove actinides from soils at Rocky Flats. Wet screening, attrition scrubbing with Calgon at high pH, attrition scrubbing at low pH, and cationic flotation were investigated. Pilot plant studies were carried out. Conceptual designs have been generated for mounting the process in semi-trailers

Rocky Mountain spotted fever, Colombia.

Science.gov (United States)

Hidalgo, Marylin; Orejuela, Leonora; Fuya, Patricia; Carrillo, Pilar; Hernandez, Jorge; Parra, Edgar; Keng, Colette; Small, Melissa; Olano, Juan P; Bouyer, Donald; Castaneda, Elizabeth; Walker, David; Valbuena, Gustavo

2007-07-01

We investigated 2 fatal cases of Rocky Mountain spotted fever that occurred in 2003 and 2004 near the same locality in Colombia where the disease was first reported in the 1930s. A retrospective serosurvey of febrile patients showed that > 21% of the serum samples had antibodies aaainst spotted fever group rickettsiae.

In situ determination of flocculated suspended material settling velocities and characteristics using a floc camera

Science.gov (United States)

Schoellhamer, David H.; Haught, Dan; Manning, Andrew

2012-01-01

Estimates of suspended sediment settling are necessary for numerical sediment models, water quality studies, and rehabilitation of coastal ecosystems. Settling of cohesive sediment, which is common in estuaries, is more difficult to quantify than noncohesive sediment because of flocculation. Flocs are composed of an aggregation of finer silts, clays, and organic material. Floc characteristics, such as the diameter, density, porosity, and water content determine floc settling velocities. A floc camera provides the ability to capture the settling velocities and other desired characteristics of individual flocs in situ. Water samples taken using a Van Dorn sampler are immediately subsampled using a pipette and transferred to the floc camera. The Perspex settling column is outfitted with a LED backlighting to distinguish flocs. The floc camera’s high pixel and temporal resolution allows image analysis software to detect individual flocs and process floc statistics per image. Observed changes in floc location with respect to time presents a way of calculating settling velocities. This work presents results of validation tests with known sediment size distributions and of deployment of the camera during a field study.

Benchmarking and performance improvement at Rocky Flats Technology Site

International Nuclear Information System (INIS)

Elliott, C.; Doyle, G.; Featherman, W.L.

1997-03-01

The Rocky Flats Environmental Technology Site has initiated a major work process improvement campaign using the tools of formalized benchmarking and streamlining. This paper provides insights into some of the process improvement activities performed at Rocky Flats from November 1995 through December 1996. It reviews the background, motivation, methodology, results, and lessons learned from this ongoing effort. The paper also presents important gains realized through process analysis and improvement including significant cost savings, productivity improvements, and an enhanced understanding of site work processes

Kawasaki disease following Rocky Mountain spotted fever: a case report.

Science.gov (United States)

Bal, Aswine K; Kairys, Steven W

2009-07-06

Kawasaki disease is an idiopathic acute systemic vasculitis of childhood. Although it simulates the clinical features of many infectious diseases, an infectious etiology has not been established. This is the first reported case of Kawasaki disease following Rocky Mountain spotted fever. We report the case of a 4-year-old girl who presented with fever and petechial rash. Serology confirmed Rocky Mountain spotted fever. While being treated with intravenous doxycycline, she developed swelling of her hands and feet. She had the clinical features of Kawasaki disease which resolved after therapy with intravenous immune globulin (IVIG) and aspirin. This case report suggests that Kawasaki disease can occur concurrently or immediately after a rickettsial illness such as Rocky Mountain spotted fever, hypothesizing an antigen-driven immune response to a rickettsial antigen.

Proceedings of the second symposium on the geology of Rocky Mountain coal, 1977

Energy Technology Data Exchange (ETDEWEB)

Hodgson, H. E. [ed.

1978-01-01

The 1977 Symposium on the Geology of Rocky Mountain Coal was held May 9 and 10 on the campus of the Colorado School of Mines in Golden, Colorado. The 1977 Symposium was sponsored by the Colorado Geological Survey and the US Geological Survey. The 1977 Symposium consisted of four technical sessions: Depositional Models for Coal Exploration in the Rocky Mountain Cretaceous; Stratigraphy and Depositional Environments of Rocky Mountain Tertiary Coal Deposits; Depositional Models for Coal Exploration in non-Rocky Mountain Regions; and Application of Geology to Coal Mining and Coal Mine Planning. Several papers discuss geophysical survey and well logging techniques applied to the exploration of coal deposits and for mine planning. Fouteen papers have been entered individually into EDB and ERA. (LTN)

The effect of a small creek valley on drainage flows in the Rocky Flats region

International Nuclear Information System (INIS)

Porch, W.

1996-01-01

Regional scale circulation and mountain-plain interactions and effects on boundary layer development are important for understanding the fate of an atmospheric release from Rocky Flats, Colorado. Numerical modeling of Front Range topographic effects near Rocky Flats have shown that though the Front Range dominates large scale flow features, small-scale terrain features near Rocky Flats are important to local transport during nighttime drainage flow conditions. Rocky Flats has been the focus of interest for the Department of Energy's Atmospheric Studies in Complex Terrain (ASCOT) program

Effects of Phytoplankton Growth Phase on Delayed Settling Behavior of Marine Snow Aggregates at Sharp Density Transitions

Science.gov (United States)

Proctor, K. W.; Montgomery, Q. W.; Prairie, J. C.

2016-02-01

Marine snow aggregates play a fundamental role in the marine carbon cycle. Since marine snow aggregates are larger and thus sink faster than individual phytoplankton, aggregates often dominate carbon flux. Previous studies have shown that marine snow aggregates will significantly decrease their settling velocity when passing through sharp density transitions within the ocean, a phenomenon defined as delayed settling. Given the importance of aggregate settling to carbon export, these small-scale changes in aggregate settling dynamics may have significant impacts on the efficiency of the biological pump. However, there is still a lack of knowledge about how different physical properties of aggregates can affect this delayed settling. In this study, we investigated the effect of phytoplankton growth phase on delayed settling behavior. Using phytoplankton cultures stopped at four different growth phases, we formed marine snow aggregates in the laboratory in rotating cylindrical tanks. We then observed individual aggregates as they settled through a stratified tank. We will present data which illustrates that aggregates experience greatly reduced settling rates when passing through sharp density gradients and that the growth phase of the phytoplankton used to form these aggregates has a significant effect on this delayed settling behavior. A thorough understanding of the impact of phytoplankton growth phase on the delayed settling behavior of marine snow will offer insight into the way phytoplankton growth phase may influence the efficiency of the biological pump, carbon flux, and the carbon cycle as a whole.

Dynamic modeling of sludge compaction and consolidation processes in wastewater secondary settling tanks

NARCIS (Netherlands)

Abusam, A.; Keesman, K.J.

2009-01-01

The double exponential settling model is the widely accepted model for wastewater secondary settling tanks. However, this model does not estimate accurately solids concentrations in the settler underflow stream, mainly because sludge compression and consolidation processes are not considered. In

Map of mixed prairie grassland vegetation, Rocky Flats, Colorado

Energy Technology Data Exchange (ETDEWEB)

Clark, S J.V.; Webber, P J; Komarkova, V; Weber, W A

1980-01-01

A color vegetation map at the scale of 1:12,000 of the area surrounding the Rocky Flats, Rockwell International Plant near Boulder, Colorado, provides a permanent record of baseline data which can be used to monitor changes in both vegetation and environment and thus to contribute to future land management and land-use policies. Sixteen mapping units based on species composition were identified, and characterized by two 10-m/sup 2/ vegetation stands each. These were grouped into prairie, pasture, and valley side on the basis of their species composition. Both the mapping units and these major groups were later confirmed by agglomerative clustering analysis of the 32 vegetation stands on the basis of species composition. A modified Bray and Curtis ordination was used to determine the environmental factor complexes controlling the distribution of vegetation at Rocky flats. Recommendations are made for future policies of environmental management and predictions of the response to environmental change of the present vegetation at the Rocky Flats site.

Extraction of Rocky Desertification from Disp Imagery: a Case Study of Liupanshui, Guizhou, China

Science.gov (United States)

Zhou, G.; Wu, Z.; Wang, W.; Shi, Y.; Mao, G.; Huang, Y.; Jia, B.; Gao, G.; Chen, P.

2017-09-01

Karst rocky desertification is a typical type of land degradation in Guizhou Province, China. It causes great ecological and economical implications to the local people. This paper utilized the declassified intelligence satellite photography (DISP) of 1960s to extract the karst rocky desertification area to analyze the early situation of karst rocky desertification in Liupanshui, Guizhou, China. Due to the lack of ground control points and parameters of the satellite, a polynomial orthographic correction model with considering altitude difference correction is proposed for orthorectification of DISP imagery. With the proposed model, the 96 DISP images from four missions are orthorectified. The images are assembled into a seamless image map of the karst area of Guizhou, China. The assembled image map is produced to thematic map of karst rocky desertification by visual interpretation in Liupanshui city. With the assembled image map, extraction of rocky desertification is conducted.

EXTRACTION OF ROCKY DESERTIFICATION FROM DISP IMAGERY: A CASE STUDY OF LIUPANSHUI, GUIZHOU, CHINA

Directory of Open Access Journals (Sweden)

G. Zhou

2017-09-01

Full Text Available Karst rocky desertification is a typical type of land degradation in Guizhou Province, China. It causes great ecological and economical implications to the local people. This paper utilized the declassified intelligence satellite photography (DISP of 1960s to extract the karst rocky desertification area to analyze the early situation of karst rocky desertification in Liupanshui, Guizhou, China. Due to the lack of ground control points and parameters of the satellite, a polynomial orthographic correction model with considering altitude difference correction is proposed for orthorectification of DISP imagery. With the proposed model, the 96 DISP images from four missions are orthorectified. The images are assembled into a seamless image map of the karst area of Guizhou, China. The assembled image map is produced to thematic map of karst rocky desertification by visual interpretation in Liupanshui city. With the assembled image map, extraction of rocky desertification is conducted.

Rocky Mountain spotted fever, Panama.

Science.gov (United States)

Estripeaut, Dora; Aramburú, María Gabriela; Sáez-Llorens, Xavier; Thompson, Herbert A; Dasch, Gregory A; Paddock, Christopher D; Zaki, Sherif; Eremeeva, Marina E

2007-11-01

We describe a fatal pediatric case of Rocky Mountain spotted fever in Panama, the first, to our knowledge, since the 1950s. Diagnosis was established by immunohistochemistry, PCR, and isolation of Rickettsia rickettsii from postmortem tissues. Molecular typing demonstrated strong relatedness of the isolate to strains of R. rickettsii from Central and South America.

Grey-box modelling of aeration tank settling.

Science.gov (United States)

Bechman, Henrik; Nielsen, Marinus K; Poulsen, Niels Kjølstad; Madsen, Henrik

2002-04-01

A model of the concentrations of suspended solids (SS) in the aeration tanks and in the effluent from these during Aeration tank settling (ATS) operation is established. The model is based on simple SS mass balances, a model of the sludge settling and a simple model of how the SS concentration in the effluent from the aeration tanks depends on the actual concentrations in the tanks and the sludge blanket depth. The model is formulated in continuous time by means of stochastic differential equations with discrete-time observations. The parameters of the model are estimated using a maximum likelihood method from data from an alternating BioDenipho waste water treatment plant (WWTP). The model is an important tool for analyzing ATS operation and for selecting the appropriate control actions during ATS, as the model can be used to predict the SS amounts in the aeration tanks as well as in the effluent from the aeration tanks.

Mixing-settling apparatus for liquid-liquid extraction

International Nuclear Information System (INIS)

Skolokin, L.I.; Leif, V.E.; Sednev, J.M.

1989-01-01

A mixing-settling apparatus for liquid-liquid extraction comprises a casing. A first partition is mounted along its longitudinal axis and above an overflow device. The mixing device is connected to a means of feeding at least one of the phases and is shaped as at least one hollow element mounted essentially perpendicularly to the longitudinal axis of the casing. The walls of the hollow element are provided with openings, the outlet cross-sections of which are directed to the first partition. The first partition is provided with a means for regulating the height of the layer of the mixed phases M in the mixing zone, said means being located in the partition at the point most distant from the means for feeding phases L, S in the longitudinal direction. A second transporting device is mounted in the settling zone. It is fixed on to the casing and is located after the overflow device in the direction of movement of the light phase l. (author) 10 figs

SVOC partitioning between the gas phase and settled dust indoors

Science.gov (United States)

Weschler, Charles J.; Nazaroff, William W.

2010-09-01

Semivolatile organic compounds (SVOCs) are a major class of indoor pollutants. Understanding SVOC partitioning between the gas phase and settled dust is important for characterizing the fate of these species indoors and the pathways by which humans are exposed to them. Such knowledge also helps in crafting measurement programs for epidemiological studies designed to probe potential associations between exposure to these compounds and adverse health effects. In this paper, we analyze published data from nineteen studies that cumulatively report measurements of dustborne and airborne SVOCs in more than a thousand buildings, mostly residences, in seven countries. In aggregate, measured median data are reported in these studies for 66 different SVOCs whose octanol-air partition coefficients ( Koa) span more than five orders of magnitude. We use these data to test a simple equilibrium model for estimating the partitioning of an SVOC between the gas phase and settled dust indoors. The results demonstrate, in central tendency, that a compound's octanol-air partition coefficient is a strong predictor of its abundance in settled dust relative to its gas phase concentration. Using median measured results for each SVOC in each study, dustborne mass fractions predicted using Koa and gas-phase concentrations correlate reasonably well with measured dustborne mass fractions ( R2 = 0.76). Combined with theoretical understanding of SVOC partitioning kinetics, the empirical evidence also suggests that for SVOCs with high Koa values, the mass fraction in settled dust may not have sufficient time to equilibrate with the gas phase concentration.

Sedimentation from flocculated suspensions in the presence of settling-driven gravitational interface instabilities

Science.gov (United States)

Rouhnia, Mohamad; Strom, Kyle

2015-09-01

We experimentally examine sedimentation from a freshwater suspension of clay flocs overlying saltwater in the presence of gravitational instabilities. The study seeks to determine: (1) if flocculation hampers or alters interface instability formation; (2) how the removal rates of sediment from the buoyant layer compare to those predicted by individual floc settling; and (3) whether or not it is possible to develop a model for effective settling velocity. The experiments were conducted in a tank at isothermal conditions. All experiments were initially stably stratified but later developed instabilities near the interface that grew into downward convecting plumes of fluid and sediment. Throughout, we measured sediment concentration in the upper and lower layers, floc size, and plume descent rates. The data showed that flocculation modifies the mixture settling velocity, and therefore shifts the mode of interface instability from double-diffusive (what one would expect from unflocculated clay) to settling-driven leaking and Rayleigh-Taylor instability formation. Removal rates of sediment from the upper layer in the presence of these instabilities were on the same order of magnitude as those predicted by individual floc settling. However, removal rates were found to better correlate with the speed of the interface plumes. A simple force-balance model was found to be capable of reasonably describing plume velocity based on concentration in the buoyant layer. This relation, coupled with a critical Grashof number and geometry relations, allowed us to develop a model for the effective settling velocity of the mixture based solely on integral values of the upper layer.

History of Rocky Flats waste streams

International Nuclear Information System (INIS)

Luckett, L.L.; Dickman, A.A.; Wells, C.R.; Vickery, D.J.

1982-01-01

An analysis of the waste streams at Rocky Flats was done to provide information for the Waste Certification program. This program has involved studying the types and amounts of retrievable transuranic (TRU) waste from Rocky Flats that is stored at the Idaho National Engineering Laboratory (INEL). The information can be used to estimate the types and amounts of waste that will need to be permanently stored in the Waste Isolation Pilot Plant (WIPP). The study covered mostly the eight-year period from June 1971 to June 1979. The types, amounts, and plutonium content of TRU waste and the areas or operations responsible for generating the waste are summarized in this waste stream history report. From the period studied, a total of 24,546,153 lbs of waste containing 211,148 g of plutonium currently occupies 709,497 cu ft of storage space at INEL

Radiological/Health physics program assessement at Rocky Flats, the process

International Nuclear Information System (INIS)

Psomas, P.O.

1996-01-01

The Department of Energy, Rocky Flats Office, Safety and Health Group, Health Physics Team (HPT) is responsible for oversight of the Radiation Protection and Health Physics Program (RPHP) of the Integrating Management Contractor (IMC), Kaiser-Hill (K-H) operations at the Rocky Flats Environmental Technology Site (RFETS). As of 1 January 1996 the Rocky Flats Plant employed 300 DOE and 4,300 contractor personnel (K-H and their subcontractors). WSI is a subcontractor and provides plant security. To accomplish the RPHP program oversight HPT personnel developed a systematic methodology for performing a functional RPHP Assessment. The initial process included development of a flow diagram identifying all programmatic elements and assessment criteria documents. Formulation of plans for conducting interviews and performance of assessments constituted the second major effort. The generation of assessment reports was the final step, based on the results of this process. This assessment will be a 6 person-year effort, over the next three years. This process is the most comprehensive assessment of any Radiation Protection and Health Physics (RPHP) Program ever performed at Rocky Flats. The results of these efforts will establish a baseline for future RPHP Program assessments at RFETS. This methodology has been well-received by contractor personnel and creates no Privacy Act violations or other misunderstandings

[Rocky Mountain spotted fever in an American tourist].

Science.gov (United States)

de Pender, A M G; Bauer, A G C; van Genderen, P J J

2005-04-02

In a 28-year-old male American tourist who presented in the hospital with fever, cold shivers, headache, nausea, myalgia and arthralgia, Rocky Mountain spotted fever was suspected, partly because he came from an endemic region (the state of Georgia). The patient was treated with doxycycline, 100 mg b.i.d.; 9 days after the first appearance of the symptoms, the diagnosis was confirmed by the report of a positive antibody titre against Rickettsia rickettsii. The patient did not have exanthema. He was discharged in good general condition after two weeks of treatment. Rocky Mountain spotted fever, caused by the Gram-negative bacterium R. rickettsii, is a serious rickettsiosis. The disease is seen only sporadically in the Netherlands because the ticks in the Netherlands do not carry the bacterium. The travel history is still not a standard component of the anamnesis and is therefore often forgotten. This can lead to under-diagnosis and delayed treatment of diseases that were formerly limited to the continent. The early recognition and treatment of Rocky Mountain spotted fever is important since delayed treatment is associated with a clear increase in both morbidity and mortality.

Kawasaki disease following Rocky Mountain spotted fever: a case report

Directory of Open Access Journals (Sweden)

Bal Aswine K

2009-07-01

Full Text Available Abstract Introduction Kawasaki disease is an idiopathic acute systemic vasculitis of childhood. Although it simulates the clinical features of many infectious diseases, an infectious etiology has not been established. This is the first reported case of Kawasaki disease following Rocky Mountain spotted fever. Case presentation We report the case of a 4-year-old girl who presented with fever and petechial rash. Serology confirmed Rocky Mountain spotted fever. While being treated with intravenous doxycycline, she developed swelling of her hands and feet. She had the clinical features of Kawasaki disease which resolved after therapy with intravenous immune globulin (IVIG and aspirin. Conclusion This case report suggests that Kawasaki disease can occur concurrently or immediately after a rickettsial illness such as Rocky Mountain spotted fever, hypothesizing an antigen-driven immune response to a rickettsial antigen.

Microthrix parvicella abundance associates with activated sludge settling velocity and rheology - Quantifying and modelling filamentous bulking

DEFF Research Database (Denmark)

Wágner, Dorottya Sarolta; Ramin, Elham; Szabo, Peter

2015-01-01

The objective of this work is to identify relevant settling velocity and rheology model parameters and to assess the underlying filamentous microbial community characteristics that can influence the solids mixing and transport in secondary settling tanks. Parameter values for hindered, transient...... and compression settling velocity functions were estimated by carrying out biweekly batch settling tests using a novel column setup through a four-month long measurement campaign. To estimate viscosity model parameters, rheological experiments were carried out on the same sludge sample using a rotational...... viscometer. Quantitative fluorescence in-situ hybridisation (qFISH) analysis, targeting Microthrix parvicella and phylum Chloroflexi, was used. This study finds that M. parvicella - predominantly residing inside the microbial flocs in our samples - can significantly influence secondary settling through...

Stochastic growth of cloud droplets by collisions during settling

Science.gov (United States)

Madival, Deepak G.

2018-04-01

In the last stage of droplet growth in clouds which leads to drizzle formation, larger droplets begin to settle under gravity and collide and coalesce with smaller droplets in their path. In this article, we shall deal with the simplified problem of a large drop settling amidst a population of identical smaller droplets. We present an expression for the probability that a given large drop suffers a given number of collisions, for a general statistically homogeneous distribution of droplets. We hope that our approach will serve as a valuable tool in dealing with droplet distribution in real clouds, which has been found to deviate from the idealized Poisson distribution due to mechanisms such as inertial clustering.

Sedimentary history and economic geology of San Juan Basin, New Mexico and Colorado

International Nuclear Information System (INIS)

Peterson, J.A.; LeLeit, A.J.; Spencer, C.W.; Ullrich, R.A.

1981-01-01

The San Juan Basin contains up to 15,000 ft of sedimentary rocks ranging in age from Cambrian to Recent. The earliest development of the area as a sedimentary basin or trough apparently took place in Pennsylvanian time, and the basin was maintained, with changing rates of subsidence and filling, through the remainder of geologic time. During the Early Paleozoic, sedimentation was dominated by marine transgressions across the northwestern flank of the regional Transcontinental Arch. The Late Paleozoic history was strongly influenced by tectonism related to development of the Ancestral Rocky Mountains Uplifts and associated downwarping. The Early Mesozoic is characterized by fluvial and eolian environments, interrupted periodically by thin marine transgressive deposits of nearshore redbeds. The final Mesozoic event was the widespread Late Cretaceous marine transgression which deposited a thick cyclic sequence of marine gray shale and sandstone, with interbedded coal. Late Tertiary regional uplift and resulting volcanism were accompanied by a regional dissection of the area by stream systems that evolved into the present drainage pattern of superposed streams. The sedimentary history is directly related to the occurrence of economic deposits in the basin. Major reserves of petroleum and gas are in Cretaceous and Pennsylvanian rocks, coal in Cretaceous, and uranium in Jurassic and Cretaceous. Abstract only

Are seagrass beds indicators of anthropogenic nutrient stress in the rocky intertidal?

International Nuclear Information System (INIS)

Honig, Susanna E.; Mahoney, Brenna; Glanz, Jess S.; Hughes, Brent B.

2017-01-01

It is well established that anthropogenic nutrient inputs harm estuarine seagrasses, but the influence of nutrients in rocky intertidal ecosystems is less clear. In this study, we investigated the effect of anthropogenic nutrient loading on Phyllospadix spp., a rocky intertidal seagrass, at local and regional scales. At sites along California, Washington, and Oregon, we demonstrated a significant, negative correlation of urban development and Phyllospadix bed thickness. These results were echoed locally along an urban gradient on the central California coast, where Phyllospadix shoot δ 15 N was negatively associated with Phyllospadix bed thickness, and experimentally, where nutrient additions in mesocosms reduced Phyllospadix shoot formation and increased epiphytic cover on Phyllospadix shoots. These findings provide evidence that coastal development can threaten rocky intertidal seagrasses through increased epiphytism. Considering that seagrasses provide vital ecosystem services, mitigating eutrophication and other factors associated with development in the rocky intertidal coastal zone should be a management priority. - Highlights: • The effect of nutrient loading on rocky intertidal seagrasses is not well studied. • Regionally, development was negatively associated with Phyllospadix bed thickness. • Locally, shoot δ 15 N was negatively associated with Phyllospadix bed thickness. • Mesocosms with added nutrients had a net loss in shoots and increased epiphytes. • Nutrient loading may have a negative effect on intertidal seagrass bed health.

Multiphase flow modelling of volcanic ash particle settling in water using adaptive unstructured meshes

Science.gov (United States)

Jacobs, C. T.; Collins, G. S.; Piggott, M. D.; Kramer, S. C.; Wilson, C. R. G.

2013-02-01

Small-scale experiments of volcanic ash particle settling in water have demonstrated that ash particles can either settle slowly and individually, or rapidly and collectively as a gravitationally unstable ash-laden plume. This has important implications for the emplacement of tephra deposits on the seabed. Numerical modelling has the potential to extend the results of laboratory experiments to larger scales and explore the conditions under which plumes may form and persist, but many existing models are computationally restricted by the fixed mesh approaches that they employ. In contrast, this paper presents a new multiphase flow model that uses an adaptive unstructured mesh approach. As a simulation progresses, the mesh is optimized to focus numerical resolution in areas important to the dynamics and decrease it where it is not needed, thereby potentially reducing computational requirements. Model verification is performed using the method of manufactured solutions, which shows the correct solution convergence rates. Model validation and application considers 2-D simulations of plume formation in a water tank which replicate published laboratory experiments. The numerically predicted settling velocities for both individual particles and plumes, as well as instability behaviour, agree well with experimental data and observations. Plume settling is clearly hindered by the presence of a salinity gradient, and its influence must therefore be taken into account when considering particles in bodies of saline water. Furthermore, individual particles settle in the laminar flow regime while plume settling is shown (by plume Reynolds numbers greater than unity) to be in the turbulent flow regime, which has a significant impact on entrainment and settling rates. Mesh adaptivity maintains solution accuracy while providing a substantial reduction in computational requirements when compared to the same simulation performed using a fixed mesh, highlighting the benefits of an

Relative importance of secondary settling tank models in WWTP simulations

DEFF Research Database (Denmark)

Ramin, Elham; Flores-Alsina, Xavier; Sin, Gürkan

2012-01-01

Results obtained in a study using the Benchmark Simulation Model No. 1 (BSM1) show that a one-dimensional secondary settling tank (1-D SST) model structure and its parameters are among the most significant sources of uncertainty in wastewater treatment plant (WWTP) simulations [Ramin et al., 2011......]. The sensitivity results consistently indicate that the prediction of sludge production is most sensitive to the variation of the settling parameters. In the present study, we use the Benchmark Simulation Model No. 2 (BSM2), a plant-wide benchmark, that combines the Activated Sludge Model No. 1 (ASM1...

Establishing bounding internal dose estimates for thorium activities at Rocky Flats.

Science.gov (United States)

Ulsh, Brant A; Rich, Bryce L; Chew, Melton H; Morris, Robert L; Sharfi, Mutty; Rolfes, Mark R

2008-07-01

As part of an evaluation of a Special Exposure Cohort petition filed on behalf of workers at the Rocky Flats Plant, the National Institute for Occupational Safety and Health (NIOSH) was required to demonstrate that bounding values could be established for radiation doses due to the potential intake of all radionuclides present at the facility. The main radioactive elements of interest at Rocky Flats were plutonium and uranium, but much smaller quantities of several other elements, including thorium, were occasionally handled at the site. Bounding potential doses from thorium has proven challenging at other sites due to the early historical difficulty in detecting this element through urinalysis methods and the relatively high internal dose delivered per unit intake. This paper reports the results of NIOSH's investigation of the uses of thorium at Rocky Flats and provides bounding dose reconstructions for these operations. During this investigation, NIOSH reviewed unclassified reports, unclassified extracts of classified materials, material balance and inventory ledgers, monthly progress reports from various groups, and health physics field logbooks, and conducted interviews with former Rocky Flats workers. Thorium operations included: (1) an experimental metal forming project with 240 kg of thorium in 1960; (2) the use of pre-formed parts in weapons mockups; (3) the removal of Th from U; (4) numerous analytical procedures involving trace quantities of thorium; and (5) the possible experimental use of thorium as a mold coating compound. The thorium handling operations at Rocky Flats were limited in scope, well-monitored and documented, and potential doses can be bounded.

Coalbed Methane Extraction and Soil Suitability Concerns in the Powder River Basin, Montana and Wyoming

Science.gov (United States)

,

2006-01-01

The Powder River Basin is located in northeastern Wyoming and southeastern Montana. It is an area of approximately 55,000 square kilometers. Extraction of methane gas from the coal seams that underlie the Powder River Basin began in Wyoming in the late 1980s and in Montana in the late 1990s. About 100-200 barrels of co-produced water per day are being extracted from each active well in the Powder River Basin, which comes to over 1.5 million barrels of water per day for all the active coalbed methane wells in the Basin. Lab testing indicates that Powder River Basin co-produced water is potable but is high in sodium and other salts, especially in the western and northern parts of the Powder River Basin. Common water management strategies include discharge of co-produced water into drainages, stock ponds, evaporation ponds, or infiltration ponds; treatment to remove sodium; or application of the water directly on the land surface via irrigation equipment or atomizers. Problems may arise because much of the Powder River Basin contains soils with high amounts of swelling clays. As part of the USGS Rocky Mountain Geographic Science Center's hyperspectral research program, researchers are investigating whether hyperspectral remote sensing data can be beneficial in locating areas of swelling clays. Using detailed hyperspectral data collected over parts of the Powder River Basin and applying our knowledge of how the clays of interest reflect energy, we will attempt to identify and map areas of swelling clays. If successful, such information will be useful to resource and land managers.

Development and validation of a novel monitoring system for batch flocculant solids settling process

DEFF Research Database (Denmark)

Valverde Pérez, Borja; Zhang, Xueqian; Penkarski-Rodon, Elena

2017-01-01

system able to monitor batch settling tests by tracking the sludge blanket height and solid concentration along the column in the range of 1 to 8 g L-1. The system could be efficiently applied to monitor the batch settling tests of several full scale treatment plants run under different operational......Secondary sedimentation is the main hydraulic bottleneck of effective pollution control WWTP under wetweather flow conditions. Therefore, online monitoring tools are required for control and optimization of the settling process under dynamic conditions. In this work we propose a novel monitoring...

Restoration of genetic connectivity among Northern Rockies wolf populations.

Science.gov (United States)

Hebblewhite, Mark; Musiani, Marco; Mills, L Scott

2010-10-01

Probably no conservation genetics issue is currently more controversial than the question of whether grey wolves (Canis lupus) in the Northern Rockies have recovered to genetically effective levels. Following the dispersal-based recolonization of Northwestern Montana from Canada, and reintroductions to Yellowstone and Central Idaho, wolves have vastly exceeded population recovery goals of 300 wolves distributed in at least 10 breeding pairs in each of Wyoming, Idaho and Montana. With >1700 wolves currently, efforts to delist wolves from endangered status have become mired in legal battles over the distinct population segment (DPS) clause of the Endangered Species Act (ESA), and whether subpopulations within the DPS were genetically isolated. An earlier study by vonHoldt et al. (2008) suggested Yellowstone National Park wolves were indeed isolated and was used against delisting in 2008. Since then, wolves were temporarily delisted, and a first controversial hunting season occurred in fall of 2009. Yet, concerns over the genetic recovery of wolves in the Northern Rockies remain, and upcoming District court rulings in the summer of 2010 will probably include consideration of gene flow between subpopulations. In this issue of Molecular Ecology, vonHoldt et al. (2010) conduct the largest analysis of gene flow and population structure of the Northern Rockies wolves to date. Using an impressive sampling design and novel analytic methods, vonHoldt et al. (2010) show substantial levels of gene flow between three identified subpopulations of wolves within the Northern Rockies, clarifying previous analyses and convincingly showing genetic recovery. © 2010 Blackwell Publishing Ltd.

CHARACTERIZATION AND SETTLING TESTS WITH TANK 51H SLURRY SAMPLES HTF-076-081

International Nuclear Information System (INIS)

HAY, MICHAEL

2006-01-01

Sludge Batch 4 (SB4) is the next sludge batch being prepared for feed to the Defense Waste Processing Facility (DWPF). SB4 includes sludge from Tanks 5F, 6F, and 11H and heels from Tanks 7F and 51H. In preparation of SB4, sludge was transferred from Tank 11H to Tank 51H. The sludge currently in Tank 51H has been found to settle at slower rates than previous sludge batches. The slow sludge settling in Tank 51H impacts the ability to wash SB4 to the desired final weight percent insoluble solids and sodium endpoint. This could impact the ability to have SB4 ready on time to support DWPF and result in increased recycle back to the Tank Farm, reduced waste loading at DWPF, and lengthened cycle time in the DWPF Chemical Processing Cell (CPC) Sludge Receipt and Adjustment Tank (SRAT). The Savannah River National Laboratory (SRNL) was requested to characterize and investigate the slower settling rate with six slurry dip samples of Tank 51H sludge. The filtered supernate and the total dried solids of the sludge were analyzed and summaries of the results published in the references listed below. The sludge composition was found to be consistent with H-Area high aluminum sludge. Difficulties were encountered with dissolving all of the material in the dried sludge solids. An analysis of the undissolved material from the digestions found the main constituent was Boehmite (AlO(OH)). This report provides all of the compositional data and an analysis of the data with recommended values to use for the composition of the Tank 51H composite sample. Tables 3-2 through 3-4 provide the composition of the Tank 51H composite sample. Settling tests conducted with the Tank 51H sludge showed a much slower settling rate than with the sludge in Sludge Batch 3 (SB3). A mixture of Tank 51H and sludge from SB3 was prepared to mimic the projected final composition of Sludge Batch 4 (SB4). The mixture showed minimal improvement in the settling rate versus Tank 51H sludge alone. An attempt to

Early Hydrodynamic Escape Limits Rocky Planets to Less Than or Equal to 1.6 Earth Radii

Science.gov (United States)

Lehmer, O. R.; Catling, D. C.

2017-01-01

In the past decade thousands of exoplanet candidates and hundreds of confirmed exoplanets have been found. For sub-Neptune-sized planets, those less than approx. 10 Earth masses, we can separate planets into two broad categories: predominantly rocky planets, and gaseous planets with thick volatile sheaths. Observations and subsequent analysis of these planets show that rocky planets are only found with radii less than approx. 1.6 Earth radii. No rocky planet has yet been found that violates this limit. We propose that hydrodynamic escape of hydrogen rich protoatmospheres, accreted by forming planets, explains the limit in rocky planet size. Following the hydrodynamic escape model employed by Luger et al. (2015), we modelled the XUV driven escape from young planets (less than approx.100 Myr in age) around a Sun-like star. With a simple, first-order model we found that the rocky planet radii limit occurs consistently at approx. 1.6 Earth radii across a wide range of plausible parameter spaces. Our model shows that hydrodynamic escape can explain the observed cutoff between rocky and gaseous planets. Fig. 1 shows the results of our model for rocky planets between 0.5 and 10 Earth masses that accrete 3 wt. % H2/He during formation. The simulation was run for 100 Myr, after that time the XUV flux drops off exponentially and hydrodynamic escape drops with it. A cutoff between rocky planets and gaseous ones is clearly seen at approx. 1.5-1.6 Earth radii. We are only interested in the upper size limit for rocky planets. As such, we assumed pure hydrogen atmospheres and the highest possible isothermal atmospheric temperatures, which will produce an upper limit on the hydrodynamic loss rate. Previous work shows that a reasonable approximation for an upper temperature limit in a hydrogen rich protoatmosphere is 2000-3000 K, consistent with our assumptions. From these results, we propose that the observed dichotomy between mini-Neptunes and rocky worlds is simply explained by

Numerical simulation of atmospheric dispersion in the vicinity of the Rocky Flats plant

International Nuclear Information System (INIS)

Bossert, J.E.; Poulos, G.S.

1993-01-01

The Atmospheric Studies in Complex Terrain (ASCOT) program sponsored a field experiment in the winter of 1991 near Rocky Flats, Colorado. Both meteorological and tracer dispersion measurements were taken. These two data sets provided an opportunity to investigate the influence of terrain-generated, radiatively-driven flows on the dispersion of the tracer. In this study, we use the Regional Atmospheric Modeling System (RAMS) to simulate meteorological conditions and tracer dispersion on the case night of 4--5 February 1991. The simulations were developed to examine the influence of nocturnal drainage flow from various topography regimes on the dispersion of tracer from the Rocky Flats plant. The simulation described herein demonstrates the extent to which Rocky Mountain drainage winds influence the flow at the mountain/plain interface for a particular case night, and shows the potential importance of canyon drainage on dispersion from the Rocky Flats area

Effect of climatic change and afforestation on water yield in the Rocky Mountain Area of North China

Directory of Open Access Journals (Sweden)

Yang Zhao

2015-04-01

Full Text Available Aim of study: We studied effects of climatic variability and afforestation on water yield to make a quantitative assessment of the hydrological effects of afforestation on basin water yield in the Rocky Mountain Area of North China. Area of study: Seven typical forest sub-watersheds in Chaobai River watershed, located near Beijing’s Miyun Reservoir, were selected as our study object. Material and methods: Annual water yield model and Separate evaluation method were applied to quantify the respective contributions of changes in climate and different vegetation types on variations in runoff. Main results: Statistical analysis indicated precipitation did not vary significantly whereas the annual runoff decreased significantly in the past decades. Although forest increased significantly in the late 20th century, climatic variations have the strongest contribution to the reductions in runoff, with the average contribution reaching 63.24%, while the remainder caused by human activities. Afforestation has a more positive impact on the reduction in runoff, with a contribution of 65.5%, which was more than the grassland of 17.6% and the farmland of 16.9%. Research highlights: Compared to the impact of climatic change, we believe the large-scale afforestation may not be the main reason for the reductions in basin water yield.

Modelling and test of aeration tank settling (ATS)

DEFF Research Database (Denmark)

Nielsen, M. K.; Bechmann, H.; Henze, Mogens

2000-01-01

The use of aeration tank settling during high hydraulic loads on large wastewater treatment plants has previously been demonstrated as a reliable technique and proven valuable. The paper proposes a simplified deterministic model to predict the efficiency of the method. It is shown...

Rocky Mountain spotted fever in Mexico: past, present, and future.

Science.gov (United States)

Álvarez-Hernández, Gerardo; Roldán, Jesús Felipe González; Milan, Néstor Saúl Hernández; Lash, R Ryan; Behravesh, Casey Barton; Paddock, Christopher D

2017-06-01

Rocky Mountain spotted fever, a tick-borne zoonosis caused by Rickettsia rickettsii, is among the most lethal of all infectious diseases in the Americas. In Mexico, the disease was first described during the early 1940s by scientists who carefully documented specific environmental determinants responsible for devastating outbreaks in several communities in the states of Sinaloa, Sonora, Durango, and Coahuila. These investigators also described the pivotal roles of domesticated dogs and Rhipicephalus sanguineus sensu lato (brown dog ticks) as drivers of epidemic levels of Rocky Mountain spotted fever. After several decades of quiescence, the disease re-emerged in Sonora and Baja California during the early 21st century, driven by the same environmental circumstances that perpetuated outbreaks in Mexico during the 1940s. This Review explores the history of Rocky Mountain spotted fever in Mexico, current epidemiology, and the multiple clinical, economic, and social challenges that must be considered in the control and prevention of this life-threatening illness. Copyright © 2017 Elsevier Ltd. All rights reserved.

FY2005 AND FY2006 CORROSION SURVEILLANCE RESULTS FOR L BASIN

International Nuclear Information System (INIS)

Vormelker, P.; Cynthia Foreman, C.

2008-01-01

This report documents the results of the L-Basin Corrosion Surveillance Program for the fiscal years 2005 and 2006. The water quality and basin conditions for the coupon immersion period are compared to the corrosion evaluation results from detailed metallurgical analysis of the coupons. Test coupons were removed from the basin on two occasions, March 29, 2005 and May 23, 2006, examined and photographed. Selected coupons were metallurgically characterized to evaluate the extent of general corrosion and pitting. Crystallographic and energy dispersive spectroscopy analysis were performed on a typical specimen, as-removed from the basin, to characterize the surface debris. Marked changes were noted in both the 2005 and 2006 specimens compared to previous years corrosion results. A new pitting incidence has occurred on the faces of the aluminum coupons compared to localized pitting at crevice regions only on specimens withdrawn in 2003 and 2004. The pitting incidence is attributed to sand filter fines that entered the basin on July 27, 2004 from an inadvertent backflush of the new sand filter. Pitting rate results show a trend of slowing down over time which is consistent with aluminum pit kinetics. Average pit growth rates were equal to or lower in all 2006 aluminum coupons than those removed in 2005. A trend line shows that pitting corrosion rates on Al1100, 6061, and 6063 coupons are slowing down since pit depth measurements were initiated in 2003. No impact to stored spent fuel is expected from the debris. The storage configuration of the majority of L-Basin spent fuel, in bundles, should provide a measure of isolation from debris settling in the basin

Settling properties of aerobic granular sludge (AGS) and aerobic granular sludge molasses (AGSM)

Science.gov (United States)

Mat Saad, Azlina; Aini Dahalan, Farrah; Ibrahim, Naimah; Yasina Yusuf, Sara; Aqlima Ahmad, Siti; Khalil, Khalilah Abdul

2018-03-01

Aerobic granulation technology is applied to treat domestic and industrial wastewater. The Aerobic granular sludge (AGS) cultivated has strong properties that appears to be denser and compact in physiological structure compared to the conventional activated sludge. It offers rapid settling for solid:liquid separation in wastewater treatment. Aerobic granules were developed using sequencing batch reactor (SBR) with intermittent aerobic - anaerobic mode with 8 cycles in 24 hr. This study examined the settling velocity performance of cultivated aerobic granular sludge (AGS) and aerobic granular sludge molasses (AGSM). The elemental composition in both AGS and AGSM were determined using X-ray fluorescence (XRF). The results showed that AGSM has higher settling velocity 30.5 m/h compared to AGS.

Basins of Attraction for Generative Justice

Science.gov (United States)

Eglash, Ron; Garvey, Colin

It has long been known that dynamic systems typically tend towards some state - an "attractor" - into which they finally settle. The introduction of chaos theory has modified our understanding of these attractors: we no longer think of the final "resting state" as necessarily being at rest. In this essay we consider the attractors of social ecologies: the networks of people, technologies and natural resources that makeup our built environments. Following the work of "communitarians" we posit that basins of attraction could be created for social ecologies that foster both environmental sustainability and social justice. We refer to this confluence as "generative justice"; a phrase which references both the "bottom-up", self-generating source of its adaptive meta stability, as well as its grounding in the ethics of egalitarian political theory.

Enhanced sediment delivery in a changing climate in semi-arid mountain basins: Implications for water resource management and aquatic habitat in the northern Rocky Mountains

Science.gov (United States)

Jaime R. Goode; Charles H. Luce; John M. Buffington

2012-01-01

The delivery and transport of sediment through mountain rivers affects aquatic habitat and water resource infrastructure. While climate change is widely expected to produce significant changes in hydrology and stream temperature, the effects of climate change on sediment yield have received less attention. In the northern Rocky Mountains, we expect climate change to...

Benchmarking and Performance Improvement at Rocky Flats Environmental Technology Site

Energy Technology Data Exchange (ETDEWEB)

Elliott, C. [Kaiser-Hill Co., LLC, Golden, CO (United States)], Doyle, D. [USDOE Rocky Flats Office, Golden, CO (United States)], Featherman, W.D. [Project Performance Corp., Sterline, VA (United States)

1997-12-31

The Rocky Flats Environmental Technology Site (RFETS) has initiated a major work process improvement campaign using the tools of formalized benchmarking and streamlining. This paper provides insights into some of the process improvement activities performed at Rocky Flats from November 1995 through December 1996. It reviews the background, motivation, methodology, results, and lessons learned from this ongoing effort. The paper also presents important gains realized through process analysis and improvement including significant cost savings, productivity improvements, and an enhanced understanding of site work processes.

Structure Changes of Macrobenthic Community on Rocky Shores After the Hebei Spirit Oil Spill

OpenAIRE

Yun-Hwan Jung; Heung-Sik Park; Kon-Tak Yoon; Hyung-Gon Lee; Chae-Woo Ma

2013-01-01

In Korea, more than 300 oil spill accidents occur every year. Despite the frequency, only a small pool of data is available on the initial effect of oil spill on macrobenthic fauna inhabiting rocky shores. The aim of this study was to analyze the variation of macrobenthic fauna composition and community structure on rocky shores, and understand the impact of oil on rocky shore organisms after the Hebei Spirit oil spill. Field surveys were carried out in five regions dose to the wreck site in ...

[Complications and cause of death in mexican children with rocky mountain spotted fever].

Science.gov (United States)

Martínez-Medina, Miguel Ángel; Rascón-Alcantar, Adela

Rocky Mountain spotted fever is a life threatening disease caused by Rickettsia rickettsia, characterized by multisystem involvement. We studied 19 dead children with Rocky Mountain spotted fever. All children who were suspected of having rickettsial infections were defined as having Rocky Mountain spotted fever by serology test and clinical features. Through the analysis of each case, we identified the clinical profile and complications associated to the death of a patient. In nine (69.2%) of 13 cases that died in the first three days of admission, the associated condition was septic shock. Others complications included respiratory distress causes by non-cardiogenic pulmonary edema, renal impairment, and multiple organ damage. The main cause of death in this study was septic shock. The fatality rate from Rocky Mountain spotted fever can be related to the severity of the infection, delay in diagnosis, and delay in initiation of antibiotic therapy. Pulmonary edema and cerebral edema can be usually precipitated by administration of excess intravenous fluids.

Settling and survival profile of enteric pathogens in the swine effluent for water reuse purpose.

Science.gov (United States)

Fongaro, G; Kunz, A; Magri, M E; Schissi, C D; Viancelli, A; Philippi, L S; Barardi, C R M

2016-11-01

The present study evaluated the pathogens persistence and settling profile in swine effluent. We determined the enteric pathogens settling characteristics, their survival and inactivation profile in swine effluent (for water reuse purpose) and in sludge (generated after aerobic treatment - during secondary settling process). The study was performed in laboratorial-scale and in full-scale (manure treatment plant). Enteric viruses and enteric bacteria were used as biomarkers. Results showed that these enteric pathogens were significantly reduced from swine effluent during secondary settling process, and enteric viruses removal was correlated with the suspended solids decantation. The design of secondary settlers can be adapted to improve pathogens removal, by diminishing the solids loading rate per area and time, ending in higher hydraulic retention times. Copyright © 2016 Elsevier GmbH. All rights reserved.

Mobility and settling rate of agglomerates of polydisperse nanoparticles

Science.gov (United States)

Spyrogianni, Anastasia; Karadima, Katerina S.; Goudeli, Eirini; Mavrantzas, Vlasis G.; Pratsinis, Sotiris E.

2018-02-01

Agglomerate settling impacts nanotoxicology and nanomedicine as well as the stability of engineered nanofluids. Here, the mobility of nanostructured fractal-like SiO2 agglomerates in water is investigated and their settling rate in infinitely dilute suspensions is calculated by a Brownian dynamics algorithm tracking the agglomerate translational and rotational motion. The corresponding friction matrices are obtained using the HYDRO++ algorithm [J. G. de la Torre, G. del Rio Echenique, and A. Ortega, J. Phys. Chem. B 111, 955 (2007)] from the Kirkwood-Riseman theory accounting for hydrodynamic interactions of primary particles (PPs) through the Rotne-Prager-Yamakawa tensor, properly modified for polydisperse PPs. Agglomerates are generated by an event-driven method and have constant mass fractal dimension but varying PP size distribution, mass, and relative shape anisotropy. The calculated diffusion coefficient from HYDRO++ is used to obtain the agglomerate mobility diameter dm and is compared with that from scaling laws for fractal-like agglomerates. The ratio dm/dg of the mobility diameter to the gyration diameter of the agglomerate decreases with increasing relative shape anisotropy. For constant dm and mean dp, the agglomerate settling rate, us, increases with increasing PP geometric standard deviation σp,g (polydispersity). A linear relationship between us and agglomerate mass to dm ratio, m/dm, is revealed and attributed to the fast Brownian rotation of such small and light nanoparticle agglomerates. An analytical expression for the us of agglomerates consisting of polydisperse PPs is then derived, us=(1/-{ρf/ρp})g 3 π μ m/dm (ρf is the density of the fluid, ρp is the density of PPs, μ is the viscosity of the fluid, and g is the acceleration of gravity), valid for agglomerates for which the characteristic rotational time is considerably shorter than their settling time. Our calculations demonstrate that the commonly made assumption of monodisperse PPs

Study of settling of peat on channel banks

Energy Technology Data Exchange (ETDEWEB)

Amaryan, L S; Bazin, Ye T; Stepanichev, V G

1983-01-01

Results are presented of studies of settling of the peat formation of the upper type on banks of drying channels. A technique is presented for forecasting evaluation in the decrease in depth of the channels because of packing of the peat on the sides of the dryers.

Mortality among plutonium and other workers at Rocky Flats

International Nuclear Information System (INIS)

Wilkinson, G.S.; Acquavella, J.F.; Reyes, M.; Tietjen, G.L.; Wiggs, L.d.; Voelz, G.L.

1985-01-01

A detailed study of mortality and radiation exposure for Rocky Flats workers was reported at the Sixteenth Mid-Year Topical Symposium of the Health Physics Society in January 1983. Significantly fewer deaths were found than were expected due to all causes, all malignant neoplasms, lung cancer, and cancer of the digestive organs. No bone cancers were observed and cancers commonly associated with radiation exposure were not more frequent than expected. Significantly more deaths than expected were observed for two causes, cancer of the prostate and benign and unspecified neoplasms. Further investigation revealed that the deaths from benign and unspecified neoplasms all involved intracranial tumors. A case control study found no association between these brain tumors and exposure to radiation, including plutonium depositions or type of occupation. The excess deaths from intracranial tumors remain unexplained but do not appear to be associated with employment at Rocky Flats. Relative risks among Rocky Flats workers with cumulative plutonium depositions of 2 nCi or more did not indicate a significantly greater risk of death among workers exposed to plutonium than among unexposed workers. Similar results were found for workers with cumulative radiation exposure of at least 1 rem. 2 references, 3 tables

Size matters for violent discharge height and settling speed of Sphagnum spores: important attributes for dispersal potential.

Science.gov (United States)

Sundberg, Sebastian

2010-02-01

Initial release height and settling speed of diaspores are biologically controlled components which are key to modelling wind dispersal. Most Sphagnum (peat moss) species have explosive spore liberation. In this study, how capsule and spore sizes affect the height to which spores are propelled were measured, and how spore size and spore number of discharged particles relate to settling speed in the aspherical Sphagnum spores. Spore discharge and spore cloud development were filmed in a closed chamber (nine species). Measurements were taken from snapshots at three stages of cloud development. Settling speed of spores (14 species) and clusters were timed in a glass tube. The maximum discharge speed measured was 3.6 m s(-1). Spores reached a maximum height of 20 cm (average: 15 cm) above the capsule. The cloud dimensions at all stages were related positively to capsule size (R(2) = 0.58-0.65). Thus species with large shoots (because they have large capsules) have a dispersal advantage. Half of the spores were released as singles and the rest as clusters (usually two to four spores). Single spores settled at 0.84-1.86 cm s(-1), about 52 % slower than expected for spherical spores with the same diameters. Settling speed displayed a positive curvilinear relationship with spore size, close to predictions by Stokes' law for spherical spores with 68 % of the actual diameters. Light-coloured spores settled slower than dark spores. Settling speed of spore clusters agrees with earlier studies. Effective spore discharge and small, slowly settling spores appear particularly important for species in forested habitats. The spore discharge heights in Sphagnum are among the greatest for small, wind-dispersed propagules. The discharge heights and the slow settling of spores affect dispersal distances positively and may help to explain the wide distribution of most boreal Sphagnum species.

Public distrust and hazard management success at the Rocky Flats nuclear weapons plant

International Nuclear Information System (INIS)

Hohenemser, C.

1987-01-01

Based on experience gained while serving a public oversight commission appointed by the governor of Colorado, hazard management at the Department of Energy's Rocky Flats nuclear weapons plant is reviewed. Specific reference is made to the plant's history of controversy, its defense-in-depth strategy of hazard control, occupational health issues, public exposure to plutonium, and the assessment of low-probability, high-consequence risks. This leads to the conclusion that Rocky flats is, by any objective standard, a hazard management success. It follows that public distrust of Rocky Flats arises as much from fear and loathing of nuclear weapons themselves as from the manufacturing process by which they are made

The removal of plutonium contaminants from Rocky Flats Plant soil

International Nuclear Information System (INIS)

Sunderland, N.R.

1987-01-01

This research was undertaken to determine if the TRUclean process could effectively remove radioactive elements from soils other than derived coral. This is an interim report prior to the project report and discusses the outcome of the tests of the Rocky Flats Plant (RFP) soil. The soil tested contained plutonium particulates in the micron and submicron range. Volume reduction and activity removal were accomplished with an overall efficiency of greater than 90%. The TRUclean process is a very practical and economical solution to soil contamination problems at the Rocky Flats Plant

Dynamic of Mud Banks In French Guiana : An Experimental Investigation of Sediment Settling Processes

Science.gov (United States)

Gratiot, N.; Lefebvre, J. P.

The coast of French Guiana is characterized by the periodic northwestward migration of mud banks originated from the Amazone mouth. From previous studies, the char- acteristical size of banks has been estimated by remote sensing processing as well as their mean rate of alongshore transport. However, the physical mecanisms leading to their displacements are not yet fully quantified. The present work aimed at investigating different processes known to be involved in coastal and estuarine dynamics and expected to occur during the migration of mud banks. The relative magnitudes of flocculation, hindered settling and consolidation have been determined. The material tested has been sampled during a field survey of the french National Pro- gram of Coastal Environment (PNEC-Chantier Guyane). Settling column experiments have been performed under quiescent condition for various mean sediment concen- trations in the range of 2-110g/l. The time dependent vertical profiles of suspended sediment concentration were monitored by mean of a 32 pre-calibrated optical sen- sors device. The corresponding settling velocity was deduced from the conservation of mass equation. This study yields usefull information for a better understanding of settling processes related to the fluid mud layer observed on the forepart of the bank. Time scales of hindering and consolidation processes are larger than these of mixing mecanisms such as tides or propagating waves. Therefore, it prevents any consolidation to occur. At the opposite, the individual floc settling velocity is too small to counterbalance the turbulent mixing induced by breaking waves. The experiments also pointed out that additional flocculation by differential settling should enhance sedimentation during slack water conditions.

Study of virgin olive oil clarification by settling under dynamic conditions.

Science.gov (United States)

Gila, Abraham; Bejaoui, Mohamed Aymen; Beltrán, Gabriel; Aguilera, María Paz; Jiménez, Antonio

2018-04-16

Vertical centrifugation is the main method for virgin olive oil (VOO) clarification. However, in recent years, settling tanks are also being used to clarify the oils from decanters. They can operate under static or dynamic conditions. In this work, vertical centrifugation and settling under dynamic conditions for VOO clarification and their effects on VOO characteristics were compared. VOO quality parameters were not affected by the clarification systems studied. The vertical centrifugal separator (VCS) showed higher clarification efficiency, giving clarified oils with higher phenol content and better sensory characteristics. VOOs clarified by dynamic settling showed notable losses of phenols and worse sensory characteristics, since the tank purge system was not efficient, with most of the impurities remaining in the tanks. The VCS with minimal water addition is a quick operation with low water consumption and is a better option to produce VOOs of improved quality, especially in terms of longer shelf life and preservation of positive sensory notes. © 2018 Society of Chemical Industry. © 2018 Society of Chemical Industry.

Hanford/Rocky Flats collaboration on development of supercritical carbon dioxide extraction to treat mixed waste

International Nuclear Information System (INIS)

Hendrickson, D.W.; Biyani, R.K.; Brown, C.M.; Teter, W.L.

1995-11-01

Proposals for demonstration work under the Department of Energy's Mixed Waste Focus Area, during the 1996 through 1997 fiscal years included two applications of supercritical carbon dioxide to mixed waste pretreatment. These proposals included task RF15MW58 of Rocky Flats and task RL46MW59 of Hanford. Analysis of compatibilities in wastes and work scopes yielded an expectation of substantial collaboration between sites whereby Hanford waste streams may undergo demonstration testing at Rocky Flats, thereby eliminating the need for test facilities at Hanford. This form of collaboration is premised the continued deployment at Rocky Flats and the capability for Hanford samples to be treated at Rocky Flats. The recent creation of a thermal treatment contract for a facility near Hanford may alleviate the need to conduct organic extraction upon Rocky Flats wastes by providing a cost effective thermal treatment alternative, however, some waste streams at Hanford will continue to require organic extraction. Final site waste stream treatment locations are not within the scope of this document

Hanford/Rocky Flats collaboration on development of supercritical carbon dioxide extraction to treat mixed waste

Energy Technology Data Exchange (ETDEWEB)

Hendrickson, D.W.; Biyani, R.K. [Westinghouse Hanford Co., Richland, WA (United States); Brown, C.M.; Teter, W.L. [Kaiser-Hill Co., Golden, CO (United States)

1995-11-01

Proposals for demonstration work under the Department of Energy`s Mixed Waste Focus Area, during the 1996 through 1997 fiscal years included two applications of supercritical carbon dioxide to mixed waste pretreatment. These proposals included task RF15MW58 of Rocky Flats and task RL46MW59 of Hanford. Analysis of compatibilities in wastes and work scopes yielded an expectation of substantial collaboration between sites whereby Hanford waste streams may undergo demonstration testing at Rocky Flats, thereby eliminating the need for test facilities at Hanford. This form of collaboration is premised the continued deployment at Rocky Flats and the capability for Hanford samples to be treated at Rocky Flats. The recent creation of a thermal treatment contract for a facility near Hanford may alleviate the need to conduct organic extraction upon Rocky Flats wastes by providing a cost effective thermal treatment alternative, however, some waste streams at Hanford will continue to require organic extraction. Final site waste stream treatment locations are not within the scope of this document.

Resuspension and settling of helminth eggs in water: Interactions with cohesive sediments.

Science.gov (United States)

Sengupta, Mita E; Andersen, Thorbjørn J; Dalsgaard, Anders; Olsen, Annette; Thamsborg, Stig M

2012-08-01

Helminth parasite eggs in low quality water represent main food safety and health hazards and are therefore important indicators used to determine whether such water can be used for irrigation. Through sedimentation helminth eggs accumulate in the sediment, however resuspension of deposited helminth eggs will lead to increased concentration of suspended eggs in the water. Our study aimed to determine the erodibility (erosion rate and erosion threshold) and settling velocity of Ascaris and Trichuris eggs as well as cohesive sediment at different time points after incorporation into the sediment. Cohesive sediment collected from a freshwater stream was used to prepare a sediment bed onto which helminth eggs were allowed to settle. The erodibility of both sediment and helminth eggs was found to decrease over time indicating that the eggs were incorporated into the surface material of the bed and that this material was stabilized through time. This interaction between eggs and bulk sediment was further manifested in an increased settling velocity of suspended eggs when sediment was present in the suspension as compared to a situation with settling in clean water. The incorporation into the sediment bed and the aggregation with sediment particles decrease the mobility of both helminth egg types. Our findings document that helminth eggs should not be viewed as single entities in water systems when modelling the distribution of eggs since both erodibility and settling velocity of eggs are determined by mobility of the sediment present in the water stream. Recalculation of the erosion threshold for helminth eggs and sediment showed that even at relatively low current velocities i.e. 0.07-0.12ms(-1) newly deposited eggs will be mobile in open irrigation channels. These environmental factors affecting resuspension must be taken into account when developing models for sedimentation of helminth eggs in different water systems. Copyright © 2012 Elsevier Ltd. All rights

Settling distances of benthic invertebrates in a sediment mobilization simulation in semi-natural flumes

Directory of Open Access Journals (Sweden)

Maria Cristina Bruno

2015-10-01

Full Text Available Drift time and distance depend on the ability of the drifting invertebrates to alter their body posture or by swimming, and these behaviors may change according to the local hydraulic environment, resulting in different distances travelled before exiting the drift. Such drift and settlement mediated invertebrate movement determine dispersal processes and ultimately generates distribution patterns within streams. We conducted an experiment in an open-air, artificial flume system directly fed by an Alpine stream, where we disturbed the sediment in the flumes, inducing catastrophic drift in the benthic community, and then assessed the settlement distances of benthic invertebrates. For each flume, we collected drift samples by disturbing the substrate at 1.5 m intervals, at increasing distance from the downstream end, for a total of 7 disturbances and a maximum settling distance of 10 m in each flume, with five replicates (i.e., five flumes for each disturbance. The disturbances induced a massive catastrophic drift in Ephemeroptera, Plecoptera and Trichoptera, always higher than the behaviorally-occurring basedrift. The Settling Index calculated over the total drift collected at each distance increased with increasing distance, and after 10 m, 90% of the drifting animals had settled. Evenness and taxa richness progressively decrease with increasing settling distance. All drifting taxa were represented mainly by young instars. We used the drift collected at 1 m from the disturbance to standardize the remaining samples, based on the assumption that 1 m is not a distance long enough to allow animals to settle at that water velocity. We calculated the percentage of possible drifters which settled by computing a Settling Index for each taxon. The drifting taxa listed by decreasing Settling Index scores were Epeorus sp., Rhithrogena semicolorata, Isoperla spp., Sericostoma spp., Ecdyonurus spp., Nemoura spp., Leuctra spp., Baetis spp., Hydropsyche spp

Computational Fluid Dynamics Modelling of Hydraulics and Sedimentation in Process Reactors During Aeration Tank Settling

DEFF Research Database (Denmark)

Dam Jensen, Mette; Ingildsen, Pernille; Rasmussen, Michael R.

2005-01-01

Aeration Tank Settling is a control method alowing settling in the process tank during high hydraulic load. The control method is patented. Aeration Tank Settling has been applied in several waste water treatment plant's using present design of the process tanks. Some process tank designs have...... shown to be more effective than others. To improve the design of less effective plants Computational Fluid Dynamics (CFD) modelling of hydraulics and sedimentation has been applied. The paper discusses the results at one particular plant experiencing problems with partly short-circuiting of the inlet...

U- and Th-series nuclides in settling particles: implications to sediment transport through surface waters and interior ocean

International Nuclear Information System (INIS)

Sarin, M.M.

2012-01-01

The Bay of Bengal is a unique ocean basin receiving large quantities of fresh water and sediment supply from several rivers draining the Indian subcontinent. The annual flux of suspended sediments discharged into the Bay of Bengal is one billion tons, about one-tenth of the global sediment discharge into the ocean. The water and sediment discharge to the Bay, show significant seasonal variation, with maximum transport coinciding with the SW-monsoon (July-September). Earlier studies on the distribution of clay minerals in sediments have led to the suggestion that the sediments of the western Bengal Fan are mainly derived from the Peninsular rivers, whereas rest of the Fan sediments is influenced by the Himalayan rivers. Settling fluxes of particulate matter through the water column of the Bay of Bengal show seasonal trends resulting from monsoon enhanced sediment supply via rivers and biological processes in the water column. It is, thus, important to understand the influence of the seasonally varying particle fluxes on the solute-particle interactions and chemical scavenging processes in the surface and deep waters of the Bay of Bengal. In this context, measurements of U- and Th-series nuclides in the settling particles are most relevant. The radionuclide fluxes ( 230 Th, 228 Th and 210 Pb) in the settling particles provide insight into the role of their removal by vertical particle flux and/or lateral transport (removal at the ocean boundaries). A study carried out in the Northern Bay of Bengal documents that the authigenic flux of 230 Th, as measured in sediment trap samples from deep waters, is balanced by its production in the overhead water column. The sediment mass flux, Al and 228 Th fluxes are similar in the settling particles through shallow and deep waters, suggesting predominant removal by vertical particle flux in the North Bay of Bengal. In the Central Bay, particulate mass, Al and 228 Th fluxes are higher in the trap material from deep waters relative

76 FR 9350 - Patient Safety Organizations: Voluntary Delisting From Rocky Mountain Patient Safety Organization

Science.gov (United States)

2011-02-17

... Organizations: Voluntary Delisting From Rocky Mountain Patient Safety Organization AGENCY: Agency for Healthcare... Organization: AHRQ has accepted a notification of voluntary relinquishment from Rocky Mountain Patient Safety Organization, a component entity of Colorado Hospital Association, of its status as a Patient Safety...

Finite elements model of a rotating half-bridge belonging to a circular settling tank

Science.gov (United States)

Dascalescu, A. E.; Lazaroiu, G.; Scupi, A. A.; Oanta, E.

2016-08-01

A circular settling tank is an open reservoir used for the gravitational separation of the sludge and of the clarified water which is discharged in the launder which is mounted at the periphery of the basin. The extraction of the sludge is done by the use of a rotating half-bridge which sweeps the sludge, vacuums it using a system of scrapping blades and suction pipes, collects it in some local sludge chambers and pour it in a central collecting tank. The rotating half-bridge is a complex structure under a complex system of loads, therefore advanced instruments of investigation are required to assess the state of strains and stresses in this structure. Until now an analytical model was developed based on the hypotheses specific to the strength of materials academic discipline. The numerical models presented in the paper use the finite element method to determine the displacements of the main beam loaded by the weight of the structure and by the Archimedes’ forces. The results of the models developed so far are conclusive for the future directions of research which aims a higher degree of accuracy of the models and of the according research methodology.

Rocky Mountain spotted fever in dogs, Brazil.

Science.gov (United States)

Labruna, Marcelo B; Kamakura, Orson; Moraes-Filho, Jonas; Horta, Mauricio C; Pacheco, Richard C

2009-03-01

Clinical illness caused by Rickettsia rickettsii in dogs has been reported solely in the United States. We report 2 natural clinical cases of Rocky Mountain spotted fever in dogs in Brazil. Each case was confirmed by seroconversion and molecular analysis and resolved after doxycycline therapy.

Sludge settling processes in SBR-related sewage treatment plants according to the Biocos method.

Science.gov (United States)

Meusel, S; Englert, R

2004-01-01

This paper describes the investigations in a sedimentation and circulation reactor (SU-reactor) of a three-phase Biocos plant. The aim of these investigations was the determination of the temporal and depth-dependent distribution of suspended solid contents, as well as describing the sludge sedimentation curves. The calculated results reveal peculiarities of the Biocos method with regard to sedimentation processes. In the hydraulically uninterrupted (pre-)settling phase, a sludge level depth was observed, which remained constant over the reactor surface and increased linearly according to the sludge volume. The settling and the thickening processes of this phase corresponded to a large extent to the well-known settling test in a one-litre measuring cylinder. During the discharge phase, the investigated settling rate was overlaid by the surface loading rate and the sludge level changed depending on the difference between those two parameters. The solid distribution of the A-phase indicated a formation of functional zones, which were influenced by the surface loading. The formation was comparable to the formation of layers in secondary settling tanks with vertical flow. The concentration equalisation between the biological reactor and the SU-reactor proved to be problematic during the circulation phase, because a type of internal sludge circulation occurred in the SU-reactor. A permanent sludge recirculation seems to be highly recommendable.

Hydrothermal Testing of K Basin Sludge and N Reactor Fuel at Sludge Treatment Project Operating Conditions

Energy Technology Data Exchange (ETDEWEB)

Delegard, Calvin H.; Schmidt, Andrew J.; Thornton, Brenda M.

2007-03-30

The Sludge Treatment Project (STP), managed for the U. S. DOE by Fluor Hanford (FH), was created to design and operate a process to eliminate uranium metal from K Basin sludge prior to packaging for Waste Isolation Pilot Plant (WIPP). The STP process uses high temperature liquid water to accelerate the reaction, produce uranium dioxide from the uranium metal, and safely discharge the hydrogen. Under nominal process conditions, the sludge will be heated in pressurized water at 185°C for as long as 72 hours to assure the complete reaction (corrosion) of up to 0.25-inch diameter uranium metal pieces. Under contract to FH, the Pacific Northwest National Laboratory (PNNL) conducted bench-scale testing of the STP hydrothermal process in November and December 2006. Five tests (~50 ml each) were conducted in sealed, un-agitated reaction vessels under the hydrothermal conditions (e.g., 7 to 72 h at 185°C) of the STP corrosion process using radioactive sludge samples collected from the K East Basin and particles/coupons of N Reactor fuel also taken from the K Basins. The tests were designed to evaluate and understand the chemical changes that may be occurring and the effects that any changes would have on sludge rheological properties. The tests were not designed to evaluate engineering aspects of the process. The hydrothermal treatment affected the chemical and physical properties of the sludge. In each test, significant uranium compound phase changes were identified, resulting from dehydration and chemical reduction reactions. Physical properties of the sludge were significantly altered from their initial, as-settled sludge values, including, shear strength, settled density, weight percent water, and gas retention.

Rocky flats closure project - lessons learned in worker stakeholder engagement

International Nuclear Information System (INIS)

Sweeney, Laura; Mazur, Robert E.; Edelson, Martin

2013-01-01

The Rocky Flats Environmental Technology Site (EPA Superfund site near Denver, Colorado) produced plutonium components for nuclear weapons for the U.S. defense program. The facility shut down in 1989 and clean up began in 1992. To ensure safe remediation of inactive nuclear sites, site owners have begun to consult stakeholders more widely in recent years. The closure of Rocky Flats aimed to set the standard for stakeholder involvement in doing the work safely, complying with regulations/standards, in a cost-effective manner. We have studied, using ethnographic methods, the extent to which workers at Rocky Flats were involved in communication and decision making strategies. Our results point out that workers can have perceptions of the site remediation process that differ from management and even other workers and that a significant number of workers questioned the commitment by management to engage the worker as stakeholder. The most effective remediation efforts should involve careful consideration of the insights and observations of all workers, particularly those who face immediate and high-level health and safety risks. (authors)

Rocky flats closure project - lessons learned in worker stakeholder engagement

Energy Technology Data Exchange (ETDEWEB)

Sweeney, Laura [Des Moines Area Community College, Ankeny, Iowa (United States); Mazur, Robert E. [Iowa State University, Ames, Iowa (United States); Edelson, Martin [Ames Laboratory-USDOE (Retired), Ames, Iowa (United States)

2013-07-01

The Rocky Flats Environmental Technology Site (EPA Superfund site near Denver, Colorado) produced plutonium components for nuclear weapons for the U.S. defense program. The facility shut down in 1989 and clean up began in 1992. To ensure safe remediation of inactive nuclear sites, site owners have begun to consult stakeholders more widely in recent years. The closure of Rocky Flats aimed to set the standard for stakeholder involvement in doing the work safely, complying with regulations/standards, in a cost-effective manner. We have studied, using ethnographic methods, the extent to which workers at Rocky Flats were involved in communication and decision making strategies. Our results point out that workers can have perceptions of the site remediation process that differ from management and even other workers and that a significant number of workers questioned the commitment by management to engage the worker as stakeholder. The most effective remediation efforts should involve careful consideration of the insights and observations of all workers, particularly those who face immediate and high-level health and safety risks. (authors)

Plutonium contamination in soils in open space and residential areas near Rocky Flats, Colorado

International Nuclear Information System (INIS)

Litaor, M.I.

1999-01-01

Spatial analysis of the 240 Pu: 239 Pu isotopic ratio of 42 soil samples collected around Rocky Flats Plant near Golden, Colorado, was conducted to assess the effect of Rocky Flats Plant activity on the soil environment. Two probability maps that quantified the uncertainty of the spatial distribution of plutonium isotopic ratios were constructed using the sequential Gaussian simulation technique (sGs). Assuming a plutonium isotopic ratio range of 0.152 ± 0.003 to 0.169 ± 0.009 is characteristic to global fallout in Colorado, and a mean value of 0.155 is representative for the Rocky Flats Plant area, the main findings of the current work were (1) the areas northwest and southwest of Rocky Flats Plant exhibited a plutonium ratio ≥0.155, this were minimally impacted by the plant activity; (2) he study area east of Rocky Flats Plant exhibited a plutonium isotopic ratio ≤0.155, which is a definitive indicator of Rocky Flats Plant-derived plutonium; and (3) inventory calculations across the study area exhibited large standard error of estimates. These errors were originated from the high variability in plutonium activity over a small sampling scale and the uncertainty in the global fallout isotopic ratio. Using the mean simulated estimates of plutonium isotopic ratio, coupled with plutonium activity measured at 11 soil pits and additional plutonium information published elsewhere, the plutonium loading on the open space and residential areas amounted to 111.2 GBq, with a standard error of estimate of 50.8 GBq

FINAL REPORT FORMER RADIATION WORKER MEDICAL SURVEILLANCE PROGRAM AT ROCKY FLATS For Department of Energy Programs

Energy Technology Data Exchange (ETDEWEB)

Joe M. Aldrich

2004-11-01

The Former Radiation Worker Medical Surveillance Program at Rocky Flats was conducted in Arvada, CO, by Oak Ridge Associated Universities through the Oak Ridge Institute for Science and Education under DOE Contract DE-AC05-00OR22750. Objectives of the program were to obtain information on the value of medical surveillance among at-risk former radiation workers and to provide long-term internal radiation dosimetry information to the scientific community. This program provided the former radiation workers of the Rocky Flats Environmental Technology Site (formerly Rocky Flats Plant) an opportunity to receive follow-up medical monitoring and a re-evaluation of their internal radiation dose. The former Rocky Flats radiation worker population is distinctive because it was a reasonably stable work force that received occupational exposures, at times substantial, over several decades. This report reflects the summation of health outcomes, statistical analyses, and dose assessment information on former Rocky Flats radiation workers to the date of study termination as of March 2004.

FINAL REPORT. FORMER RADIATION WORKER MEDICAL SURVEILLANCE PROGRAM AT ROCKY FLATS For Department of Energy Programs

International Nuclear Information System (INIS)

Aldrich, Joe M.

2004-01-01

The Former Radiation Worker Medical Surveillance Program at Rocky Flats was conducted in Arvada, CO, by Oak Ridge Associated Universities through the Oak Ridge Institute for Science and Education under DOE Contract DE-AC--05-00OR22750. Objectives of the program were to obtain information on the value of medical surveillance among at-risk former radiation workers and to provide long-term internal radiation dosimetry information to the scientific community. This program provided the former radiation workers of the Rocky Flats Environmental Technology Site (formerly Rocky Flats Plant) an opportunity to receive follow-up medical monitoring and a re-evaluation of their internal radiation dose. The former Rocky Flats radiation worker population is distinctive because it was a reasonably stable work force that received occupational exposures, at times substantial, over several decades. This report reflects the summation of health outcomes, statistical analyses, and dose assessment information on former Rocky Flats radiation workers to the date of study termination as of March 2004

Produced water ponds are an important source of aromatics and alcohols in Rocky Mountain oil and gas basins

Science.gov (United States)

Lyman, S. N.

2017-12-01

Most of the water extracted with oil and natural gas (i.e., produced water) is disposed of by injection into the subsurface. In the arid western United States, however, a significant portion of produced water is discharged in ponds for evaporative disposal, and produced water is often stored in open ponds prior to subsurface injection. Even though they are common in the West (Utah's Uinta Basin has almost 200 ha), produced water ponds have been excluded from oil and gas emissions inventories because little information about their emission rates and speciation is available. We used flux chambers and inverse plume modeling to measure emissions of methane, C2-C11 hydrocarbons, light alcohols, carbonyls, and carbon dioxide from oil and gas produced water storage and disposal ponds in the Uinta Basin and the Upper Green River Basin, Wyoming, during 2013-2017. Methanol was the most abundant organic compound in produced water (91 ± 2% of the total volatile organic concentration; mean ± 95% confidence interval) but accounted for only 25 ± 30% of total organic compound emissions from produced water ponds. Non-methane hydrocarbons, especially C6-C9 alkanes and aromatics, accounted for the majority of emitted organics. We were able to predict emissions of individual compounds based on water concentrations, but only to within an order of magnitude. The speciation and magnitude of emissions varied strongly across facilities and was influenced by water age, the presence or absence of oil sheens, and with meteorological conditions (especially ice cover). Flux chamber measurements were lower than estimates from inverse modeling techniques.Based on our flux chamber measurements, we estimate that produced water ponds are responsible for between 3 and 9% of all non-methane organic compound emissions in the Uinta Basin (or as much as 18% if we rely on our inverse modeling results). Emissions from produced water ponds contain little methane and are more reactive (i.e., they have

Residue management at Rocky Flats

International Nuclear Information System (INIS)

Olencz, J.

1995-01-01

Past plutonium production and manufacturing operations conducted at the Rocky Flats Environmental Technology Site (RFETS) produced a variety of plutonium-contaminated by-product materials. Residues are a category of these materials and were categorized as open-quotes materials in-processclose quotes to be recovered due to their inherent plutonium concentrations. In 1989 all RFETS plutonium production and manufacturing operations were curtailed. This report describes the management of plutonium bearing liquid and solid wastes

Rocky Flats Solar Evaporation Ponds RCRA hybrid-closure case study

International Nuclear Information System (INIS)

Ogg, R.T.; Everett, L.G.; Cullen, S.J.

1994-01-01

The Solar Evaporation Ponds (SEP)/Operable Unit 4 (OU 4), located at the Rocky Flats Plant (RFP) sixteen miles northwest of Denver, Colorado, is currently undergoing remediation/Resource Conservation and Recovery Act (RCRA) closure in accordance with the Rocky Flats Interagency Agreement (IAG) signed by the US Department of Energy (DOE), US Environmental Protection Agency (EPA) and Colorado Department of Health (CDH) on January 22, 1991. Based on the ''Phase 1'' (source and soils) RCRA Facility Investigation/Remedial Investigation (RFM data and interpretations), the DOE and EG and G Rocky Flats, Inc. (EG and G) have selected a permanent surface engineered/isolation barrier as the technological option for remediation of the SEP. The DOE and EG and G will utilize all natural materials to create an ''impermeable'' barrier/structure to isolate the waste being left in place from impacting human health and the environment for a minimum of 1,000 years. Their rationale for utilizing natural materials is two fold; (1) optimize long term performance of the barrier and; (2) design a structure which will be near maintenance free (passive remediation) for 1,000 years. The DOE and EG and G have taken a proactive approach in providing post closure performance assessment for this RCRA closure action. An integrated monitoring system has been designed which will include monitoring the engineered barrier, vadose zone and ground water systems. Rocky Flats will integrate instrumentation into the permanent engineered barrier which will provide early warning of potential liquid migration through the barrier and into the waste zone

Effects of Time, Heat, and Oxygen on K Basin Sludge Agglomeration, Strength, and Solids Volume

Energy Technology Data Exchange (ETDEWEB)

Delegard, Calvin H.; Sinkov, Sergey I.; Schmidt, Andrew J.; Daniel, Richard C.; Burns, Carolyn A.

2011-01-04

Sludge disposition will be managed in two phases under the K Basin Sludge Treatment Project. The first phase is to retrieve the sludge that currently resides in engineered containers in the K West (KW) Basin pool at ~10 to 18°C. The second phase is to retrieve the sludge from interim storage in the sludge transport and storage containers (STSCs) and treat and package it in preparation for eventual shipment to the Waste Isolation Pilot Plant. The work described in this report was conducted to gain insight into how sludge may change during long-term containerized storage in the STSCs. To accelerate potential physical and chemical changes, the tests were performed at temperatures and oxygen partial pressures significantly greater than those expected in the T Plant canyon cells where the STSCs will be stored. Tests were conducted to determine the effects of 50°C oxygenated water exposure on settled quiescent uraninite (UO2) slurry and a full simulant of KW containerized sludge to determine the effects of oxygen and heat on the composition and mechanical properties of sludge. Shear-strength measurements by vane rheometry also were conducted for UO2 slurry, mixtures of UO2 and metaschoepite (UO3•2H2O), and for simulated KW containerized sludge. The results from these tests and related previous tests are compared to determine whether the settled solids in the K Basin sludge materials change in volume because of oxidation of UO2 by dissolved atmospheric oxygen to form metaschoepite. The test results also are compared to determine if heating or other factors alter sludge volumes and to determine the effects of sludge composition and settling times on sludge shear strength. It has been estimated that the sludge volume will increase with time because of a uranium metal → uraninite → metaschoepite oxidation sequence. This increase could increase the number of containers required for storage and increase overall costs of sludge management activities. However, the volume

Effects of Time, Heat, and Oxygen on K Basin Sludge Agglomeration, Strength, and Solids Volume

International Nuclear Information System (INIS)

Delegard, Calvin H.; Sinkov, Sergey I.; Schmidt, Andrew J.; Daniel, Richard C.; Burns, Carolyn A.

2011-01-01

Sludge disposition will be managed in two phases under the K Basin Sludge Treatment Project. The first phase is to retrieve the sludge that currently resides in engineered containers in the K West (KW) Basin pool at ∼10 to 18 C. The second phase is to retrieve the sludge from interim storage in the sludge transport and storage containers (STSCs) and treat and package it in preparation for eventual shipment to the Waste Isolation Pilot Plant. The work described in this report was conducted to gain insight into how sludge may change during long-term containerized storage in the STSCs. To accelerate potential physical and chemical changes, the tests were performed at temperatures and oxygen partial pressures significantly greater than those expected in the T Plant canyon cells where the STSCs will be stored. Tests were conducted to determine the effects of 50 C oxygenated water exposure on settled quiescent uraninite (UO 2 ) slurry and a full simulant of KW containerized sludge to determine the effects of oxygen and heat on the composition and mechanical properties of sludge. Shear-strength measurements by vane rheometry also were conducted for UO 2 slurry, mixtures of UO2 and metaschoepite (UO 3 · 2H 2 O), and for simulated KW containerized sludge. The results from these tests and related previous tests are compared to determine whether the settled solids in the K Basin sludge materials change in volume because of oxidation of UO2 by dissolved atmospheric oxygen to form metaschoepite. The test results also are compared to determine if heating or other factors alter sludge volumes and to determine the effects of sludge composition and settling times on sludge shear strength. It has been estimated that the sludge volume will increase with time because of a uranium metal → uraninite → metaschoepite oxidation sequence. This increase could increase the number of containers required for storage and increase overall costs of sludge management activities. However, the

Comparative risk analysis for the Rocky Flats Plant integrated project planning

International Nuclear Information System (INIS)

Jones, M.E.; Shain, D.I.

1994-01-01

The Rocky Flats Plant is developing, with active stakeholder a comprehensive planning strategy that will support transition of the Rocky Flats Plant from a nuclear weapons production facility to site cleanup and final disposition. Final disposition of the Rocky Flats Plant materials and contaminants requires consideration of the interrelated nature of sitewide problems, such as material movement and disposition, facility and land use endstates, costs relative risks to workers and the public, and waste disposition. Comparative Risk Analysis employs both incremental risk and cumulative risk evaluations to compare risks from postulated options or endstates. These postulated options or endstates can be various remedial alternatives, or future endstate uses of federal agency land. Currently, there does not exist any approved methodology that aggregates various incremental risk estimates. Comparative Risk Analysis has been developed to aggregate various incremental risk estimates to develop a site cumulative risk estimate. This paper discusses development of the Comparative Risk Analysis methodology, stakeholder participation and lessons learned from these challenges

The rocky flats controversy on radionuclide soil action levels

International Nuclear Information System (INIS)

Earle, T.C.

2004-01-01

An account of the Rocky Flats radionuclide soil action level controversy is presented as: a case study for the purpose of understanding the nature and value of stakeholder involvement in the management of radiological hazards. The report consists of three main sections. The first section outlines the Rocky Flats story, including the Cold War era, which was characterised by secrecy and distrust, the post-Cold War era, in which trust and co-operation between risk managers and the public began to develop. This contrast between these two historical periods provides the context necessary to understand the radionuclide soil action level controversy, the main events of which are described in the second section. In the final section, the Rocky Flats case is briefly discussed within the framework of a general model of stakeholder involvement and the lessons learned from the case are identified: (1) without a basis in shared values, collaborative public involvement in the management of radiological hazards is not possible; (2) given a basis in shared values, collaborative public involvement can lead to improved solutions to the management of radiological hazards; and (3) risk managers should therefore seek to understand the values of public stakeholders and to identify ways, through stakeholder involvement, that those values can be incorporated in management practice. (author)

DUST TRANSPORT IN PROTOSTELLAR DISKS THROUGH TURBULENCE AND SETTLING

International Nuclear Information System (INIS)

Turner, N. J.; Carballido, A.; Sano, T.

2010-01-01

We apply ionization balance and magnetohydrodynamical (MHD) calculations to investigate whether magnetic activity moderated by recombination on dust grains can account for the mass accretion rates and the mid-infrared spectra and variability of protostellar disks. The MHD calculations use the stratified shearing-box approach and include grain settling and the feedback from the changing dust abundance on the resistivity of the gas. The two-decade spread in accretion rates among solar-mass T Tauri stars is too large to result solely from variations in the grain size and stellar X-ray luminosity, but can plausibly be produced by varying these parameters together with the disk magnetic flux. The diverse shapes and strengths of the mid-infrared silicate bands can come from the coupling of grain settling to the distribution of the magnetorotational turbulence, through the following three effects. First, recombination on grains 1 μm or smaller yields a magnetically inactive dead zone extending more than two scale heights from the midplane, while turbulent motions in the magnetically active disk atmosphere overshoot the dead zone boundary by only about one scale height. Second, grains deep in the dead zone oscillate vertically in wave motions driven by the turbulent layer above, but on average settle at the rates found in laminar flow, so that the interior of the dead zone is a particle sink and the disk atmosphere will become dust-depleted unless resupplied from elsewhere. Third, with sufficient depletion, the dead zone is thinner and mixing dredges grains off the midplane. The last of these processes enables evolutionary signatures such as the degree of settling to sometimes decrease with age. The MHD results also show that the magnetic activity intermittently lifts clouds of small grains into the atmosphere. Consequently the photosphere height changes by up to one-third over timescales of a few orbits, while the extinction along lines of sight grazing the disk surface

Mobility and settling rate of agglomerates of polydisperse nanoparticles.

Science.gov (United States)

Spyrogianni, Anastasia; Karadima, Katerina S; Goudeli, Eirini; Mavrantzas, Vlasis G; Pratsinis, Sotiris E

2018-02-14

Agglomerate settling impacts nanotoxicology and nanomedicine as well as the stability of engineered nanofluids. Here, the mobility of nanostructured fractal-like SiO 2 agglomerates in water is investigated and their settling rate in infinitely dilute suspensions is calculated by a Brownian dynamics algorithm tracking the agglomerate translational and rotational motion. The corresponding friction matrices are obtained using the HYDRO++ algorithm [J. G. de la Torre, G. del Rio Echenique, and A. Ortega, J. Phys. Chem. B 111, 955 (2007)] from the Kirkwood-Riseman theory accounting for hydrodynamic interactions of primary particles (PPs) through the Rotne-Prager-Yamakawa tensor, properly modified for polydisperse PPs. Agglomerates are generated by an event-driven method and have constant mass fractal dimension but varying PP size distribution, mass, and relative shape anisotropy. The calculated diffusion coefficient from HYDRO++ is used to obtain the agglomerate mobility diameter d m and is compared with that from scaling laws for fractal-like agglomerates. The ratio d m /d g of the mobility diameter to the gyration diameter of the agglomerate decreases with increasing relative shape anisotropy. For constant d m and mean d p , the agglomerate settling rate, u s , increases with increasing PP geometric standard deviation σ p,g (polydispersity). A linear relationship between u s and agglomerate mass to d m ratio, m/d m , is revealed and attributed to the fast Brownian rotation of such small and light nanoparticle agglomerates. An analytical expression for the u s of agglomerates consisting of polydisperse PPs is then derived, u s =1-ρ f ρ p g3πμmd m (ρ f is the density of the fluid, ρ p is the density of PPs, μ is the viscosity of the fluid, and g is the acceleration of gravity), valid for agglomerates for which the characteristic rotational time is considerably shorter than their settling time. Our calculations demonstrate that the commonly made assumption of

Effects of Turbulence on Settling Velocities of Synthetic and Natural Particles

Science.gov (United States)

Jacobs, C.; Jendrassak, M.; Gurka, R.; Hackett, E. E.

2014-12-01

For large-scale sediment transport predictions, an important parameter is the settling or terminal velocity of particles because it plays a key role in determining the concentration of sediment particles within the water column as well as the deposition rate of particles onto the seabed. The settling velocity of particles is influenced by the fluid dynamic environment as well as attributes of the particle, such as its size, shape, and density. This laboratory study examines the effects of turbulence, generated by an oscillating grid, on both synthetic and natural particles for a range of flow conditions. Because synthetic particles are spherical, they serve as a reference for the natural particles that are irregular in shape. Particle image velocimetry (PIV) and high-speed imaging systems were used simultaneously to study the interaction between the fluid mechanics and sediment particles' dynamics in a tank. The particles' dynamics were analyzed using a custom two-dimensional tracking algorithm used to obtain distributions of the particle's velocity and acceleration. Turbulence properties, such as root-mean-square turbulent velocity and vorticity, were calculated from the PIV data. Results are classified by Stokes number, which was based-on the integral scale deduced from the auto-correlation function of velocity. We find particles with large Stokes numbers are unaffected by the turbulence, while particles with small Stokes numbers primarily show an increase in settling velocity in comparison to stagnant flow. The results also show an inverse relationship between Stokes number and standard deviation of the settling velocity. This research enables a better understanding of the interdependence between particles and turbulent flow, which can be used to improve parameterizations in large-scale sediment transport models.

Computational fluid dynamics modelling of hydraulics and sedimentation in process reactors during aeration tank settling.

Science.gov (United States)

Jensen, M D; Ingildsen, P; Rasmussen, M R; Laursen, J

2006-01-01

Aeration tank settling is a control method allowing settling in the process tank during high hydraulic load. The control method is patented. Aeration tank settling has been applied in several waste water treatment plants using the present design of the process tanks. Some process tank designs have shown to be more effective than others. To improve the design of less effective plants, computational fluid dynamics (CFD) modelling of hydraulics and sedimentation has been applied. This paper discusses the results at one particular plant experiencing problems with partly short-circuiting of the inlet and outlet causing a disruption of the sludge blanket at the outlet and thereby reducing the retention of sludge in the process tank. The model has allowed us to establish a clear picture of the problems arising at the plant during aeration tank settling. Secondly, several process tank design changes have been suggested and tested by means of computational fluid dynamics modelling. The most promising design changes have been found and reported.

Cascading effects of fire exclusion in the Rocky Mountain ecosystems: a literature review

Science.gov (United States)

Robert E. Keane; Kevin C. Ryan; Tom T. Veblen; Craig D. Allen; Jessie Logan; Brad Hawkes

2002-01-01

The health of many Rocky Mountain ecosystems is in decline because of the policy of excluding fire in the management of these ecosystems. Fire exclusion has actually made it more difficult to fight fires, and this poses greater risks to the people who fight fires and for those who live in and around Rocky Mountain forests and rangelands. This paper discusses the extent...

Gravitational settling of a highly concentrated system of solid spherical particles

Science.gov (United States)

Arkhipov, V. A.; Usanina, A. S.

2017-09-01

In the present paper, we report on the results of an experimental study of the process of gravity sedimentation of a cloud of monodispersed solid spherical particles with initial volume concentration C > 0.03, which was performed in a wide range of Reynolds numbers. An analytical estimate of the settling regimes of spherical particle clouds is presented. A new method for creating a spherical particle cloud with a high concentration of particles is proposed. A qualitative picture of the settling process of a highly concentrated particle cloud under gravity is revealed. A criterial dependence for the drag coefficient of a sedimenting spherical particle cloud as an entity is obtained.

Evaluation of SNODAS snow depth and snow water equivalent estimates for the Colorado Rocky Mountains, USA

Science.gov (United States)

Clow, David W.; Nanus, Leora; Verdin, Kristine L.; Schmidt, Jeffrey

2012-01-01

The National Weather Service's Snow Data Assimilation (SNODAS) program provides daily, gridded estimates of snow depth, snow water equivalent (SWE), and related snow parameters at a 1-km2 resolution for the conterminous USA. In this study, SNODAS snow depth and SWE estimates were compared with independent, ground-based snow survey data in the Colorado Rocky Mountains to assess SNODAS accuracy at the 1-km2 scale. Accuracy also was evaluated at the basin scale by comparing SNODAS model output to snowmelt runoff in 31 headwater basins with US Geological Survey stream gauges. Results from the snow surveys indicated that SNODAS performed well in forested areas, explaining 72% of the variance in snow depths and 77% of the variance in SWE. However, SNODAS showed poor agreement with measurements in alpine areas, explaining 16% of the variance in snow depth and 30% of the variance in SWE. At the basin scale, snowmelt runoff was moderately correlated (R2 = 0.52) with SNODAS model estimates. A simple method for adjusting SNODAS SWE estimates in alpine areas was developed that uses relations between prevailing wind direction, terrain, and vegetation to account for wind redistribution of snow in alpine terrain. The adjustments substantially improved agreement between measurements and SNODAS estimates, with the R2 of measured SWE values against SNODAS SWE estimates increasing from 0.42 to 0.63 and the root mean square error decreasing from 12 to 6 cm. Results from this study indicate that SNODAS can provide reliable data for input to moderate-scale to large-scale hydrologic models, which are essential for creating accurate runoff forecasts. Refinement of SNODAS SWE estimates for alpine areas to account for wind redistribution of snow could further improve model performance. Published 2011. This article is a US Government work and is in the public domain in the USA.

Comparative risk analysis for the Rocky Flats Plant integrated project planning

International Nuclear Information System (INIS)

Jones, M.E.; Shain, D.I.

1994-01-01

The Rocky Flats Plant is developing, with active stakeholder participation, a comprehensive planning strategy that will support transition of the Rocky Flats Plant from a nuclear weapons production facility to site cleanup and final disposition. Consideration of the interrelated nature of sitewide problems, such as material movement and disposition, facility and land use endstates, costs, relative risks to workers and the public, and waste disposition are all needed. Comparative Risk Analysis employs both incremental risk and cumulative risk evaluations to compare risks from postulated options or endstates and is an analytical tool for the Rocky Flats Plant Integrated Project Planning which can assist a decision-maker in evaluating relative risks among proposed remediation activity. However, risks from all of the remediation activities, decontamination and decommissioning activities, and normal ongoing operations are imposed upon the Rocky Flats workers, the surrounding public, and the environment. Comparative Risk Analysis will provide risk information, both human health and ecological, to aid in reducing unnecessary resource and monetary expenditures by focusing these resources on the largest risks first. Comparative Risk Analysis has been developed to aggregate various incremental risk estimates to develop a site cumulative risk estimate. The Comparative Risk Analysis methodology Group, consisting of community stakeholders, was established. Early stakeholder involvement in the risk analysis methodology development provides an opportunity for stakeholders to influence the risk information delivered to a decision-maker. This paper discusses development of the Comparative Risk Analysis methodology, stakeholder participation and lessons learned from these challenges

Kepler's first rocky planet

DEFF Research Database (Denmark)

Batalha, N.M.; Borucki, W.J.; Bryson, S.T.

2011-01-01

NASA's Kepler Mission uses transit photometry to determine the frequency of Earth-size planets in or near the habitable zone of Sun-like stars. The mission reached a milestone toward meeting that goal: the discovery of its first rocky planet, Kepler-10b. Two distinct sets of transit events were...... tests on the photometric and pixel flux time series established the viability of the planet candidates triggering ground-based follow-up observations. Forty precision Doppler measurements were used to confirm that the short-period transit event is due to a planetary companion. The parent star is bright...

Settling time of dental x-ray tube head after positioning

International Nuclear Information System (INIS)

Yun, Suk Ja; Kang, Byung Cheol; Wang, Se Myung; Koh, Chang Sung

2002-01-01

The aim of this study was to introduce a method of obtaining the oscillation graphs of the dental x-ray tube heads relative to time using an accelerometer. An Accelerometer, Piezotron type 8704B25 (Kistler Instrument Co., Amherst, NY, USA) was utilized to measure the horizontal oscillation of the x-ray tube head immediately after positioning the tube head for an intraoral radiograph. The signal from the sensor was transferred to a dynamic signal analyzer, which displayed the magnitude of the acceleration on the Y-axis and time lapse on the X-axis. The horizontal oscillation of the tube head was measured relative to time, and the settling time was also determined on the basis of the acceleration graphs for 6 wall type, 5 floor-fixed type, and 4 mobile type dental x-ray machines. The oscillation graphs showed that tube head movement decreased rapidly over time. The settling time varied with x-ray machine types. Wall-type x-ray machines had a settling time of up to 6 seconds, 5 seconds for fixed floor-types, and 11 seconds for the mobile-types. Using an accelerometer, we obtained the oscillation graphs of the dental x-ray tube head relative to time. The oscillation graph with time can guide the operator to decide upon the optimum exposure moment after xray tube head positioning for better radiographic resolution.

Settling time of dental x-ray tube head after positioning

Energy Technology Data Exchange (ETDEWEB)

Yun, Suk Ja; Kang, Byung Cheol [Department of Oral and Maxillofacial Radiology, Chonnam National University, Gwangju (Korea, Republic of); Wang, Se Myung; Koh, Chang Sung [Department of Mechatronics, Kwangju Institute of Science and Technology, Gwangju (Korea, Republic of)

2002-09-15

The aim of this study was to introduce a method of obtaining the oscillation graphs of the dental x-ray tube heads relative to time using an accelerometer. An Accelerometer, Piezotron type 8704B25 (Kistler Instrument Co., Amherst, NY, USA) was utilized to measure the horizontal oscillation of the x-ray tube head immediately after positioning the tube head for an intraoral radiograph. The signal from the sensor was transferred to a dynamic signal analyzer, which displayed the magnitude of the acceleration on the Y-axis and time lapse on the X-axis. The horizontal oscillation of the tube head was measured relative to time, and the settling time was also determined on the basis of the acceleration graphs for 6 wall type, 5 floor-fixed type, and 4 mobile type dental x-ray machines. The oscillation graphs showed that tube head movement decreased rapidly over time. The settling time varied with x-ray machine types. Wall-type x-ray machines had a settling time of up to 6 seconds, 5 seconds for fixed floor-types, and 11 seconds for the mobile-types. Using an accelerometer, we obtained the oscillation graphs of the dental x-ray tube head relative to time. The oscillation graph with time can guide the operator to decide upon the optimum exposure moment after xray tube head positioning for better radiographic resolution.

Summary of surface-water-quality data collected for the Northern Rockies Intermontane Basins National Water-Quality Assessment Program in the Clark Fork-Pend Oreille and Spokane River basins, Montana, Idaho, and Washington, water years 1999-2001

Science.gov (United States)

Beckwith, Michael A.

2003-01-01

Water-quality samples were collected at 10 sites in the Clark Fork-Pend Oreille and Spokane River Basins in water years 1999 – 2001 as part of the Northern Rockies Intermontane Basins (NROK) National Water-Quality Assessment (NAWQA) Program. Sampling sites were located in varied environments ranging from small streams and rivers in forested, mountainous headwater areas to large rivers draining diverse landscapes. Two sampling sites were located immediately downstream from the large lakes; five sites were located downstream from large-scale historical mining and oreprocessing areas, which are now the two largest “Superfund” (environmental remediation) sites in the Nation. Samples were collected during a wide range of streamflow conditions, more frequently during increasing and high streamflow and less frequently during receding and base-flow conditions. Sample analyses emphasized major ions, nutrients, and selected trace elements. Streamflow during the study ranged from more than 130 percent of the long-term average in 1999 at some sites to 40 percent of the long-term average in 2001. River and stream water in the study area exhibited small values for specific conductance, hardness, alkalinity, and dissolved solids. Dissolved oxygen concentrations in almost all samples were near saturation. Median total nitrogen and total phosphorus concentrations in samples from most sites were smaller than median concentrations reported for many national programs and other NAWQA Program study areas. The only exceptions were two sites downstream from large wastewater-treatment facilities, where median concentrations of total nitrogen exceeded the national median. Maximum concentrations of total phosphorus in samples from six sites exceeded the 0.1 milligram per liter threshold recommended for limiting nuisance aquatic growth. Concentrations of arsenic, cadmium, copper, lead, mercury, and zinc were largest in samples from sites downstream from historical mining and ore

Concentration-driven models revisited: towards a unified framework to model settling tanks in water resource recovery facilities

OpenAIRE

Torfs, Elena; Marti, M. Carmen; Locatelli, Florent; Balemans, Sophie; Burger, Raimund; Diehl, Stefan; Laurent, Julien; Vanrolleghem, Peter A.; Francois, Pierre; Nopens, Ingmar

2017-01-01

A new perspective on the modelling of settling behaviour in water resource recovery facilities is introduced. The ultimate goal is to describe in a unified way the processes taking place both in primary settling tanks (PSTs) and secondary settling tanks (SSTs) for a more detailed operation and control. First, experimental evidence is provided, pointing out distributed particle properties (such as size, shape, density, porosity, and flocculation state) as an important common source of distribu...

Geomorphic evolution of the San Luis Basin and Rio Grande in southern Colorado and northern New Mexico

Science.gov (United States)

Ruleman, Chester A.; Machette, Michael; Thompson, Ren A.; Miggins, Dan M; Goehring, Brent M; Paces, James B.

2016-01-01

The San Luis Basin encompasses the largest structural and hydrologic basin of the Rio Grande rift. On this field trip, we will examine the timing of transition of the San Luis Basin from hydrologically closed, aggrading subbasins to a continuous fluvial system that eroded the basin, formed the Rio Grande gorge, and ultimately, integrated the Rio Grande from Colorado to the Gulf of Mexico. Waning Pleistocene neotectonic activity and onset of major glacial episodes, in particular Marine Isotope Stages 11–2 (~420–14 ka), induced basin fill, spillover, and erosion of the southern San Luis Basin. The combined use of new geologic mapping, fluvial geomorphology, reinterpreted surficial geology of the Taos Plateau, pedogenic relative dating studies, 3He surface exposure dating of basalts, and U-series dating of pedogenic carbonate supports a sequence of events wherein pluvial Lake Alamosa in the northern San Luis Basin overflowed, and began to drain to the south across the closed Sunshine Valley–Costilla Plain region ≤400 ka. By ~200 ka, erosion had cut through topographic highs at Ute Mountain and the Red River fault zone, and began deep-canyon incision across the southern San Luis Basin. Previous studies indicate that prior to 200 ka, the present Rio Grande terminated into a large bolson complex in the vicinity of El Paso, Texas, and systematic, headward erosional processes had subtly integrated discontinuously connected basins along the eastern flank of the Rio Grande rift and southern Rocky Mountains. We propose that the integration of the entire San Luis Basin into the Rio Grande drainage system (~400–200 ka) was the critical event in the formation of the modern Rio Grande, integrating hinterland basins of the Rio Grande rift from El Paso, Texas, north to the San Luis Basin with the Gulf of Mexico. This event dramatically affected basins southeast of El Paso, Texas, across the Chisos Mountains and southeastern Basin and Range province, including the Rio

A high resolution complex terrain dispersion study in the Rocky Flats, Colorado vicinity

International Nuclear Information System (INIS)

Poulos, G.S.; Bossert, J.E.

1992-01-01

In January/February, 1991 an intensive set of measurements was taken around Rocky Flats near Denver, CO under the auspices of the Department of Energy Atmospheric Studies over Complex Terrain (ASCOT) program. This region of the country is known as the Front Range, and is characterized by a transition from the relatively flat terrain of the Great Plains to the highly varied terrain of the Rocky Mountains. One goal of the ASCOT 1991 program was to gain insight into multi-scale meteorological interaction by observing wintertime drainage conditions at the mountain-valley-plains interface. ASCOT data included surface and upper air measurements on approximately a 50km 2 scale. Simultaneously, an SF 6 tracer release study was being conducted around Rocky Flats, a nuclear materials production facility. Detailed surface concentration measurements were completed for the SF 6 plume. This combination of meteorological and tracer concentration data provided a unique data set for comparisons of mesoscale and dispersion modeling results with observations and for evaluating our capability to predict pollutant transport. Our approach is to use the Regional Atmospheric Modeling System (RAMS) mesoscale model to simulate atmospheric conditions and the Lagrangian Particle Dispersion Model (LPDM), a component of the RAMS system, to model the dispersion of the SF 6 . We have chosen the 4--5 February, 1991 overnight period as our case study. This night was characterized by strong drainage flows from the Rocky Mountains to the west of Rocky Flats, southerly winds in a layer about lkm thick above the drainage flows, and northwesterly winds above that layer extending to the tropopause

Basin-edge generated Rayleigh waves in the Almaty basin and corresponding consequences for ground motion amplification

Science.gov (United States)

Pilz, Marco; Parolai, Stefano; Petrovic, Bojana; Silacheva, Natalya; Abakanov, Tanatkan; Orunbaev, Sagynbek; Moldobekov, Bolot

2018-04-01

During the past two centuries, several large earthquakes have caused extensive damages in the city of Almaty in Kazakhstan. Increasing the preparedness for future events, the definition of the optimal engineering designs for civil structures and the corresponding mitigation of earthquake risks involves the accomplishment of site response studies. To this regard, a temporary seismological network of 15 stations was installed in the city aiming at the accurate identification of local variations of site response at different locations. As the city is settled on a deep sediment-filled plain with laterally strongly varying thicknesses, bound to the south by the Tien-Shan mountain range, the city might face important site effects: large amplification and significant increase of shaking duration. In addition, surface waves in the low-frequency range around and slightly higher than the fundamental resonance frequency, which could be generated at the boundaries of the basin, can carry a large amount of energy. In turn, this will influence both the spatial distribution of the level of amplification and the temporal lengthening of ground motion significantly. For quantifying these effects, we apply complex trace analysis, which uses the instantaneous polarization characteristics of the seismic signal for separating waves arriving at a single site from different directions. In this way, secondary surface waves originating at various sites along the edge of the Almaty basin can be identified as well as their generation regions. After having assessed 1-D amplification effects with well-established techniques like the standard spectral ratio and the horizontal-to-vertical spectral ratio techniques, the results further indicate that thick layers of soft clay deposits and the 3-D structure of the basin give rise to lengthening of ground motion and high amplification values at low frequencies around 0.2 Hz. The steep structure of the sediment-bedrock interface at the southern edge

Limber pine health in the Canadian Rockies

Science.gov (United States)

Cyndi M. Smith; David Langor; Colin Myrholm; Jim Weber; Cameron Gillies; Jon Stuart-Smith

2011-01-01

Limber pine (Pinus flexilis) reaches the northern limit of its range at about 52 degrees latitude in Alberta (AB) and 51 degrees latitude in British Columbia (BC). Most populations are found on the eastern slopes of the Rocky Mountains, with a few disjunct populations west of the Continental Divide in southeastern BC.

A consistent modelling methodology for secondary settling tanks: a reliable numerical method.

Science.gov (United States)

Bürger, Raimund; Diehl, Stefan; Farås, Sebastian; Nopens, Ingmar; Torfs, Elena

2013-01-01

The consistent modelling methodology for secondary settling tanks (SSTs) leads to a partial differential equation (PDE) of nonlinear convection-diffusion type as a one-dimensional model for the solids concentration as a function of depth and time. This PDE includes a flux that depends discontinuously on spatial position modelling hindered settling and bulk flows, a singular source term describing the feed mechanism, a degenerating term accounting for sediment compressibility, and a dispersion term for turbulence. In addition, the solution itself is discontinuous. A consistent, reliable and robust numerical method that properly handles these difficulties is presented. Many constitutive relations for hindered settling, compression and dispersion can be used within the model, allowing the user to switch on and off effects of interest depending on the modelling goal as well as investigate the suitability of certain constitutive expressions. Simulations show the effect of the dispersion term on effluent suspended solids and total sludge mass in the SST. The focus is on correct implementation whereas calibration and validation are not pursued.

Settling of a cylindrical particle in a stagnant fluid

DEFF Research Database (Denmark)

Sørensen, Henrik; Rosendahl, Lasse; Yin, Chungen

The objective of this work is to collect data and develop models for cylindrical particles which could be used in numerical multiphase flow modeling. Trajectories of cylindrical particles settling in stagnant water are filmed from two directions in order to derive detailed information on their mo...

Numerical simulation of particle settling and cohesion in liquid

Energy Technology Data Exchange (ETDEWEB)

Johno, Y; Nakashima, K; Shigematsu, T; Ono, B [SASEBO National College of Technology, 1-1 Okishin, Sasebo, Nagasaki, 857-1193 (Japan); Satomi, M, E-mail: yjohno@post.cc.sasebo.ac.j [Sony Semiconductor Kyushu Corporation, Kikuchigun, Kumamoto (Japan)

2009-02-01

In this study, the motions of particles and particle clusters in liquid were numerically simulated. The particles of two sizes (Dp=40mum and 20mum) settle while repeating cohesion and dispersion, and finally the sediment of particles are formed at the bottom of a hexahedron container which is filled up with pure water. The flow field was solved with the Navier-Stokes equations and the particle motions were solved with the Lagrangian-type motion equations, where the interaction between fluid and particles due to drag forces were taken into account. The collision among particles was calculated using Distinct Element Method (DEM), and the effects of cohesive forces by van der Waals force acting on particle contact points were taken into account. Numerical simulations were performed under conditions in still flow and in shear flow. It was found that the simulation results enable us to know the state of the particle settling and the particle condensation.

Public involvement and risk communiction for the Rocky Flats health studies

International Nuclear Information System (INIS)

Zoda, S.M.; Lockhart, A.J.

1993-01-01

In 1990, the State of Colorado and the U.S. Department of Energy entered into an Agreement in Principle that provides funding for state studies and monitoring of the Rocky Flats Nuclear Weapons Plant. The Colorado Department of Health initiated a two-phase study to identify releases of radioactive and other contaminants from the year 1952, when Rocky Flats opened, through 1989, and to estimate the potential offsite exposures and health effects. Because one of the main goals for the study is to answer citizen questions about past operations and impacts from the Rocky Flats Plant, the Department of Health designed an open study process featuring a multi-faceted program for public involvement and two-way communication. To provide independent scientific oversight and increase public accountability, Governor Roy Romer appointed a 12-member Health Advisory Panel that includes local and national technical experts and community members. This paper describes the study process and the public involvement and risk communication program designed to address citizen concerns, foster understanding and build credibility

78 FR 70033 - Encana Marketing (USA) Inc. v. Rockies Express Pipeline LLC; Notice of Complaint

Science.gov (United States)

2013-11-22

... Marketing (USA) Inc. v. Rockies Express Pipeline LLC; Notice of Complaint Take notice that on November 15... Commission (Commission), 18 CFR 385.206, Encana Marketing (USA) Inc. (Encana Marketing or Complainant), filed... Rockies Express has unlawfully denied Encana Marketing's request to make changes to the primary delivery...

Depth-variable settlement patterns and predation influence on newly settled reef fishes (Haemulon spp., Haemulidae.

Directory of Open Access Journals (Sweden)

Lance K B Jordan

Full Text Available During early demersal ontogeny, many marine fishes display complex habitat-use patterns. Grunts of the speciose genus Haemulon are among the most abundant fishes on western North Atlantic coral reefs, with most species settling to shallow habitats (≤12 m. To gain understanding into cross-shelf distributional patterns exhibited by newly settled stages of grunts (<2 cm total length, we examined: 1 depth-specific distributions of congeners at settlement among sites at 8 m, 12 m, and 21 m, and 2 depth-variable predation pressure on newly settled individuals (species pooled. Of the six species identified from collections of newly settled specimens (n = 2125, Haemulon aurolineatum (tomtate, H. flavolineatum (French grunt, and H. striatum (striped grunt comprised 98% of the total abundance; with the first two species present at all sites. Prevalence of H. aurolineatum and H. flavolineatum decreased substantially from the 8-m site to the two deeper sites. In contrast, H. striatum was absent from the 8-m site and exhibited its highest frequency at the 21-m site. Comparison of newly settled grunt delta density for all species on caged (predator exclusion and control artificial reefs at the shallowest site (8-m revealed no difference, while the 12-m and 21-m sites exhibited significantly greater delta densities on the caged treatment. This result, along with significantly higher abundances of co-occurring piscivorous fishes at the deeper sites, indicated lower predation pressure at the 8-m site. This study suggests habitat-use patterns of newly settled stages of some coral reef fishes that undergo ontogenetic shifts are a function of depth-variable predation pressure while, for at least one deeper-water species, proximity to adult habitat appears to be an important factor affecting settlement distribution.

Disposal of Rocky Flats residues as waste

International Nuclear Information System (INIS)

Dustin, D.F.; Sendelweck, V.S.

1993-01-01

Work is underway at the Rocky Flats Plant to evaluate alternatives for the removal of a large inventory of plutonium-contaminated residues from the plant. One alternative under consideration is to package the residues as transuranic wastes for ultimate shipment to the Waste Isolation Pilot Plant. Current waste acceptance criteria and transportation regulations require that approximately 1000 cubic yards of residues be repackaged to produce over 20,000 cubic yards of WIPP certified waste. The major regulatory drivers leading to this increase in waste volume are the fissile gram equivalent, surface radiation dose rate, and thermal power limits. In the interest of waste minimization, analyses have been conducted to determine, for each residue type, the controlling criterion leading to the volume increase, the impact of relaxing that criterion on subsequent waste volume, and the means by which rules changes may be implemented. The results of this study have identified the most appropriate changes to be proposed in regulatory requirements in order to minimize the costs of disposing of Rocky Flats residues as transuranic wastes

Risk, media, and stigma at Rocky Flats

International Nuclear Information System (INIS)

Flynn, J.; Peters, E.; Mertz, C.K.; Slovic, P.

1998-01-01

Public responses to nuclear technologies are often strongly negative. Events, such as accidents or evidence of unsafe conditions at nuclear facilities, receive extensive and dramatic coverage by the news media. These news stories affect public perceptions of nuclear risks and the geographic areas near nuclear facilities. One result of these perceptions, avoidance behavior, is a form of technological stigma that leads to losses in property values near nuclear facilities. The social amplification of risk is a conceptual framework that attempts to explain how stigma is created through media transmission of information about hazardous places and public perceptions and decisions. This paper examines stigma associated with the US Department of energy's Rocky Flats facility, a major production plant in the nation's nuclear weapons complex, located near Denver, Colorado. This study, based upon newspaper analyses and a survey of Denver area residents, finds that the social amplification theory provides a reasonable framework for understanding the events and public responses that took place in regard to Rocky Flats during a 6-year period, beginning with an FBI raid of the facility in 1989

Variation of Vegetation Ecological Water Consumption and Its Response to Vegetation Coverage Changes in the Rocky Desertification Areas in South China.

Science.gov (United States)

Wan, Long; Tong, Jing; Zhou, Jinxing; Guo, Hongyan; Cui, Ming; Liu, Yuguo; Ning, Like; Tang, Fukai

2016-01-01

Over the past several decades, rocky desertification has led to severe ecological problems in karst areas in South China. After a rocky desertification treatment project was completed, the vegetation coverage changed greatly and, consequently, increased the ecology water consumption (approximately equal to the actual evapotranspiration) of the regional vegetation. Thus, it intensified the regional water stresses. This study explored the changes in the actual evapotranspiration (ETa) response to the vegetation coverage changes in the rocky desertification areas in South China based on the precipitation (P), potential evapotranspiration (ETp) and NDVI (the normalized difference vegetation index) datasets. The revised Bagrov model was used to simulate the actual evapotranspiration changes with the supposed increasing NDVI. The results indicated that the average NDVI value was lower when the rocky desertification was more severe. The ETa, evapotranspiration efficiency (ETa/ETp) and potential humidity (P/ETp) generally increased with the increasing NDVI. The sensitivity of the ETa response to vegetation coverage changes varied due to different precipitation conditions and different rocky desertification severities. The ETa was more sensitive under drought conditions. When a drought occurred, the ETa exhibited an average increase of 40~60 mm with the NDVI increasing of 0.1 in the rocky desertification areas. Among the 5 different severity categories of rocky desertification, the ETa values' responses to NDVI changes were less sensitive in the severe rocky desertification areas but more sensitive in the extremely and potential rocky desertification areas. For example, with the NDVI increasing of 0.025, 0.05, 0.075, and 0.1, the corresponding ETa changes increased by an average of 2.64 mm, 10.62 mm, 19.19 mm, and 27.58 mm, respectively, in severe rocky desertification areas but by 4.94 mm, 14.99 mm, 26.80, and 37.13 mm, respectively, in extremely severe rocky

Settling for less out of fear of being single.

Science.gov (United States)

Spielmann, Stephanie S; MacDonald, Geoff; Maxwell, Jessica A; Joel, Samantha; Peragine, Diana; Muise, Amy; Impett, Emily A

2013-12-01

The present research demonstrates that fear of being single predicts settling for less in romantic relationships, even accounting for constructs typically examined in relationship research such as anxious attachment. Study 1 explored the content of people's thoughts about being single. Studies 2A and 2B involved the development and validation of the Fear of Being Single Scale. Study 2C provided preliminary support for the hypothesis that fear of being single predicts settling for less in ongoing relationships, as evidenced by greater dependence in unsatisfying relationships. Study 3 replicated this effect in a longitudinal study demonstrating that fear of being single predicts lower likelihood of initiating the dissolution of a less satisfying relationship. Studies 4A and 4B explored the predictive ability of fear of being single for self-reported dating standards. Across both samples, fear of being single was unrelated to self-reported standards for a mate, with the exception of consistently higher standards for parenting. Studies 5 and 6 explored romantic interest in targets that were manipulated to vary in responsiveness and physical attractiveness. These studies found that fear of being single consistently predicted romantic interest in less responsive and less attractive dating targets. Study 7 explored fear of being single during a speed-dating event. We found that fear of being single predicted being less selective in expressing romantic interest but did not predict other daters' romantic interest. Taken together, the present research suggests that fear of being single is a meaningful predictor of settling for less in relationships. PsycINFO Database Record (c) 2013 APA, all rights reserved.

Monitoring and troubleshooting of non-filamentous settling and dewatering problems in an industrial activated sludge treatment plant

DEFF Research Database (Denmark)

Kjellerup, B. V.; Keiding, Kristian; Nielsen, Per Halkjær

2001-01-01

dewaterability. The monitoring program revealed that a deterioration of the floc strength and the settling properties in the process tanks was closely connected to downstream dewatering problems and poor effluent quality. Particularly severe problems were observed a few weeks after the production at the factory......A large industrial activated sludge wastewater treatment plant had temporary problems with settling and dewatering of the sludge. Microscopical investigations revealed that the poor settling properties were not due to presence of filamentous bacteria, but poor floc properties. In order...... to characterise the changes in floc properties that led to settling and dewatering problems and to find reasons for this taking place, a comprehensive monitoring program was conducted during more than one year. The monitoring program included various measurements of floc settleability, floc strength and sludge...

Low power fast settling multi-standard current reusing CMOS fractional-N frequency synthesizer

Institute of Scientific and Technical Information of China (English)

Lou Wenfeng; Feng Peng; Wang Haiyong; Wu Nanjian

2012-01-01

A low power fast settling multi-standard CMOS fractional-N frequency synthesizer is proposed.The current reusing and frequency presetting techniques are adopted to realize the low power fast settling multi-standard fractional-N frequency synthesizer.An auxiliary non-volatile memory (NVM) is embedded to avoid the repetitive calibration process and to save power in practical application.This PLL is implemented in a 0.18μm technology.The frequency range is 0.3 to 2.54 GHz and the settling time is less than 5μs over the entire frequency range.The LC-VCO with the stacked divide-by-2 has a good figure of merit of-193.5 dBc/Hz.The measured phase noise of frequency synthesizer is about -115 dBc/Hz at 1 MHz offset when the carrier frequency is 2.4 GHz and the reference spurs are less than -52 dBc.The whole frequency synthesizer consumes only 4.35 mA @ 1.8 V.

Polymer aids for settling and filtration of oil sands tailings

Energy Technology Data Exchange (ETDEWEB)

Wang, X. [Alberta Univ., Edmonton, AB (Canada). Dept. of Chemical and Materials Engineering; Energy Resources Conservation Board, Calgary, AB (Canada). Oil Sands Section; Xu, Z.; Masliyah, J.H. [Alberta Univ., Edmonton, AB (Canada). Dept. of Chemical and Materials Engineering

2008-07-01

Oil sand tailings are segregated into coarse and fine tailings. High volumes of toxic fluids and tailings are created in the process. Tailings ponds are an environmental risk with high operating and maintenance costs. Current commercial technologies uses chemical additions to create recycled water and composite tailings (CT). Researchers are now investigating centrifuged and dry mature fine tailings (MFT). Filtration processes with flocculants are used to separate the tailings into warm recycle water and dried cakes that can be used in reclamation processes. Studies are being conducted to find a polymer than can effectively flocculate and filter whole oil sands tailings. The filtration procedure uses pressure to produce released water. Polymers include magnafloc and Al-PAM polymer concentrations are used in slurry masses. Tests have been conducted to determine the settling rates of the polymers. The tests showed that Al-PAM filtered the tailings effectively. Paraffinic froth treatment tests have also been conducted to determine settling rates. A cake produced with froth treatment tailings of Al-PAM 400 ppm had a water content 42.5 wt per cent. The tests showed that while Magnafloc 1011 is a good settling aid, but a poor filtration addition. Al-PAM aided in both the flocculation and filtration processes. Higher Al-PAM dosages are needed for froth treatment tailings processes. It was concluded that dry cakes are produced with the addition of Al-PAM. tabs., figs.

Morphostructural characterization of the Charco basin and its surrounding areas in the Chihuahua segment of north Mexican Basin and Range Province

Science.gov (United States)

Troiani, Francesco; Menichetti, Marco

2014-05-01

The Chihuahua Basin and Range (CBR) is the eastern branch of the northern Mexican Basin and Range Province that, from a morphostructural point of view, presently is one amongst the lesser-known zones of the southern portion of the North America Basin and Range Province. The study area covers an approximately 800 km2-wide portion of the CBR and encompasses the fault-bounded Charco basin and its surrounding areas. The bedrock of the area pertains to the large siliceous-igneous province of the Sierra Madre Occidental and consists of volcanoclastic rocks including Oligocene dacite, rhyolite, rhyolitic tuffs, and polimitic conglomerates. The region is characterized by a series of NW-SE oriented valleys delimited by tilted monoclinal blocks bounded by high angle, SW-dipping, normal faults. Abrupt changes in elevation, alternating between narrow faulted mountain chains and flat arid valleys or basins are the main morphological elements of the area. The valleys correspond to structural grabens filled with Plio-Pleistocene continental sediments. These grabens are about 10 km wide, while the extensional fault system extend over a distance of more than 15 km. The mountain ranges are in most cases continuous over distances that range from 10 to 70 km including different branches of the extensional and transfer faults. The morphogenesis is mainly erosive in character: erosional landforms (such as rocky scarps, ridges, strath-terraces, erosional pediment, reverse slopes, landslide scar zones, litho-structural flat surfaces) dominate the landscape. In contrast, Quaternary depositional landforms are mainly concentrated within the flat valleys or basins. The Quaternary deposits consist of wide alluvial fans extending to the foot of the main ridges, fluvial and debris-slope deposits. The morphostructural characterization of the area integrated different methodologies, including: i) geomorphological and structural field analyses; ii) remote sensing and geo-morphometric investigations

Mobilization and mixing of settled solids in horizontal storage tanks

International Nuclear Information System (INIS)

Cummins, R.L.

1995-01-01

Studies were conducted using submerged jets for the mobilization and mixing of settled solids to form a suspension that can easily be removed from storage tanks. These studies focus on the specific problems relating to horizontal, cylindrical storage tanks. Of primary consideration are the storage tanks located at the Oak Ridge National Laboratory which are used for the collection of remote-handled, radioactive liquid wastes. These wastes are in two phases. A layer of undissolved, settled solids varying from 2 to 4 feet in depth under a layer of supernate. Using a surrogate of the tank contents and an approximate 2/3 dimensional scale tank, tests were performed to determine the optimum design and location of suction and discharge nozzles as well as the minimum discharge velocity required to achieve complete mobilization of the solids in the tank

37 CFR 10.67 - Settling similar claims of clients.

Science.gov (United States)

2010-07-01

... clients. 10.67 Section 10.67 Patents, Trademarks, and Copyrights UNITED STATES PATENT AND TRADEMARK OFFICE... Office Code of Professional Responsibility § 10.67 Settling similar claims of clients. A practitioner who represents two or more clients shall not make or participate in the making of an aggregate settlement of the...

Significance of settling model structures and parameter subsets in modelling WWTPs under wet-weather flow and filamentous bulking conditions

DEFF Research Database (Denmark)

Ramin, Elham; Sin, Gürkan; Mikkelsen, Peter Steen

2014-01-01

Current research focuses on predicting and mitigating the impacts of high hydraulic loadings on centralized wastewater treatment plants (WWTPs) under wet-weather conditions. The maximum permissible inflow to WWTPs depends not only on the settleability of activated sludge in secondary settling tanks...... (SSTs) but also on the hydraulic behaviour of SSTs. The present study investigates the impacts of ideal and non-ideal flow (dry and wet weather) and settling (good settling and bulking) boundary conditions on the sensitivity of WWTP model outputs to uncertainties intrinsic to the one-dimensional (1-D...... of settling parameters to the total variance of the key WWTP process outputs significantly depends on the influent flow and settling conditions. The magnitude of the impact is found to vary, depending on which type of 1-D SST model is used. Therefore, we identify and recommend potential parameter subsets...

Strategy and plan for siting and licensing a Rocky Mountain low-level radioactive waste facility

International Nuclear Information System (INIS)

Whitman, M.

1983-09-01

In 1979, the States of Nevada and Washington temporarily closed their commercial low-level radioactive waste (LLW) disposal facilities and South Carolina, the only other state hosting such a facility, restricted the amount of waste it would accept. All three states then announced that they did not intend to continue the status quo of accepting all of the country's commercial low-level radioactive waste. Faced with this situation, other states began considering alternative LLW management and disposal options. In the Rocky Mountain region, this evolved into discussions for the development of an interstate compact to manage low-level waste. Inherent in this management plan was a strategy to site and license a new LLW disposal facility for the Rocky Mountain region. The Rocky Mountain Low-Level Radioactive Waste Compact was negotiated over the course of a year, with final agreement on the language of the compact agreed to in early 1982. States eligible to join the compact are Arizona, Colorado, Nevada, New Mexico, Utah, and Wyoming. Colorado adopted the compact into law in 1982, and Nevada, New Mexico and Wyoming adopted it in 1983. Utah has joined the Northwest Compact, although it may decide to join the Rocky Mountain Compact after a new disposal facility is developed for the region. Arizona has taken no action on the Rocky Mountain Compact

Palaeoenvironments and facies on a progressively flooded rocky island (Upper Cenomanian – Lower Turonian, Bohemian Cretaceous Basin)

Czech Academy of Sciences Publication Activity Database

Žítt, Jiří; Vodrážka, R.; Hradecká, L.; Svobodová, Marcela

2010-01-01

Roč. 179, - (2010), s. 223-234 ISSN 1802-6842 Institutional research plan: CEZ:AV0Z30130516 Keywords : Cretaceous island * weathering * geomorphology * sedimentary environments * biostratigraphy * Upper Cenomanian-Lower Turonian * Bohemian Cretaceous Basin Subject RIV: DB - Geology ; Mineralogy http://www.nm.cz/publikace/archiv-en.php?id=1&rok=179&f_=Show

Geochemistry of suspended and settling solids in two freshwater lakes.

NARCIS (Netherlands)

Koelmans, A.A.

1998-01-01

This study describes the 1987–1992 time variationof the bulk chemical composition, levels of heavymetals, arsenic, nitrogen and phosporous insuspended and settling solids in Lake Volkerak andLake Zoom (The Netherlands). Suspended and setlingsolids were collected with continuous flowcentrifuges and

Characteristics and settling behaviour of particles from blast furnace flue gas washing.

Science.gov (United States)

Kiventerä, Jenni; Leiviskä, Tiina; Keski-Ruismäki, Kirsi; Tanskanen, Juha

2016-05-01

A lot of particles from iron-making are removed with blast furnace off-gas and routed to the gas cleaning system. As water is used for cleaning the gas, the produced wash water contains a large amount of particles such as valuable Fe and C. However, the presence of zinc prevents recycling. In addition, the high amount of calcium results in uncontrolled scaling. Therefore, the properties of the wash water from scrubber and sludge, from the Finnish metal industry (SSAB Raahe), were evaluated in this study. Size fractionation of wash water revealed that Fe, Zn, Al, Mn, V, Cr and Cd appeared mainly in the larger fractions (>1.2 μm) and Na, Mg, Si, Ni, K, Cu and As appeared mainly in the smaller fractions (<1.2 μm) or in dissolved form. Calcium was found both in the larger fractions and dissolved (∼60 mg/L). Most of the particles in wash water were included in the 1.2-10 μm particle size and were settled effectively. However, a clear benefit was observed when using a chemical to enhance particle settling. In comparison to 2.5 h of settling without chemical, the turbidity was further decreased by about 94%, iron 85% and zinc 50%. Coagulation-flocculation experiments indicated that both low and high molecular weight cationic polymers could provide excellent purification results in terms of turbidity. Calcium should be removed by other methods. The particles in sludge were mostly in the 2-4 μm or 10-20 μm fractions. Further sludge settling resulted in high solids removal. Copyright © 2016 Elsevier Ltd. All rights reserved.

Low-level radioactive waste facility siting in the Rocky Mountain compact region

International Nuclear Information System (INIS)

Whitman, M.

1983-09-01

The puprose of the Rocky Mountain Low-Level Radioactive Waste Compact is to develop a regional management system for low-level waste (LLW) generated in the six states eligible for membership: Arizona, Colorado, Nevada, New Mexico, Utah and Wyoming. Under the terms of the compact, any party state generating at least 20% of the region's waste becomes responsible for hosting a regional LLW management facility. However, the compact prescribes no system which the host state must follow to develop a facility, but rather calls on the state to fulfill its responsibility through reliance on its own laws and regulations. Few of the Rocky Mountain compact states have legislation dealing specifically with LLW facility siting. Authority for LLW facility siting is usually obtained from radiation control statutes and solid or hazardous waste statutes. A state-by-state analysis of the siting authorities of each of the Rock Mountain compact states as they pertain to LLW disposal facility siting is presented. Siting authority for LLW disposal facilities in the Rocky Mountain compact region runs from no authority, as in Wyoming, to general statutory authority for which regulations would have to be promulgated, as in Arizona and Nevada, to more detailed siting laws, as in Colorado and New Mexico. Barring an amendment to, or different interpretation of, the Utah Hazardous Waste Facility Siting Act, none of the Rocky Mountain States' LLW facility siting authorities preempt local veto authorities

Rocky Flats Plant Site, Golden, Colorado. Volume I. Draft environmental impact statement

International Nuclear Information System (INIS)

1977-09-01

Two previous environmental statements have been issued for the Rocky Flats Plant site. One concerned a new plutonium recovery facility (WASH-1517, USAEC, January 1972); the second concerned land acquisition (WASH-1518, USAEC, April 1972). This document responds to those who indicated concerns and also ERDA's anticipated concerns about activities associated with the Rocky Flats Plant. Most concerns focus on two points including the Plant's involvement in the production of nuclear weapons and the Plant's handling of hazardous materials, particularly the radioactive element plutonium. The production of nuclear weapons, in which the Rocky Flats Plant maintains a vital role, will probably continue for as long as the world situation suggests that this country must have a strong defense. Operations at the Rocky Flats Plant have resulted in some plutonium being released to the environment, but evidence does not indicate that the amounts involved have presented any measurable hazard to human health. Ongoing improvements to the Plant's facilities and operational procedures are intended to preclude any recurrence of past releases. Despite these improvements, some public concern has resulted from past releases and the potential adverse effects from any possible future releases. This DEIS addresses that concern. It comments on past mishaps along with their causes and effects. It discusses current operations plus related costs and benefits to the region. Various alternatives to continuing present operations are explored, and the costs and benefits of the different options are compared

Differences in in vitro dissolution properties of settled and airborne uranium material

International Nuclear Information System (INIS)

Scripsick, R.C.; Crist, K.C.; Tillery, M.I.; Soderholm, S.C.

1984-01-01

The dissolution behavior of settled and airborne uranium material produced by firing of depleted uranium munitions was studied using an in vitro dissolution technique. Differences in the composition of bulk and respirable fraction samples of these materials were observed. Dissolution analysis results suggest that under some conditions a rapidly dissolving uranium fraction may be formed. This fraction may play an important role in determining hazard potential associated with inhalation exposure to uranium materials. The fact that a larger rapidly dissolving fraction was observed in the airborne material than in the settled material indicates that dissolution analysis should be performed on appropriate size fraction samples. 20 references, 3 figures, 4 tables

A layered model for inclined pipe flow of settling slurry

Czech Academy of Sciences Publication Activity Database

Matoušek, Václav; Krupička, Jan; Kesely, Mikoláš

2018-01-01

Roč. 333, June (2018), s. 317-326 ISSN 0032-5910 R&D Projects: GA ČR GA17-14271S Institutional support: RVO:67985874 Keywords : inclined pipe * settling slurry * pressure drop * flow stratification * laboratory loop Impact factor: 2.942, year: 2016

Deposition of reactive nitrogen during the Rocky Mountain Airborne Nitrogen and Sulfur (RoMANS) study

International Nuclear Information System (INIS)

Beem, Katherine B.; Raja, Suresh; Schwandner, Florian M.; Taylor, Courtney; Lee, Taehyoung; Sullivan, Amy P.; Carrico, Christian M.; McMeeking, Gavin R.; Day, Derek; Levin, Ezra; Hand, Jenny; Kreidenweis, Sonia M.; Schichtel, Bret; Malm, William C.; Collett, Jeffrey L.

2010-01-01

Increases in reactive nitrogen deposition are a growing concern in the U.S. Rocky Mountain west. The Rocky Mountain Airborne Nitrogen and Sulfur (RoMANS) study was designed to improve understanding of the species and pathways that contribute to nitrogen deposition in Rocky Mountain National Park (RMNP). During two 5-week field campaigns in spring and summer of 2006, the largest contributor to reactive nitrogen deposition in RMNP was found to be wet deposition of ammonium (34% spring and summer), followed by wet deposition of nitrate (24% spring, 28% summer). The third and fourth most important reactive nitrogen deposition pathways were found to be wet deposition of organic nitrogen (17%, 12%) and dry deposition of ammonia (14%, 16%), neither of which is routinely measured by air quality/deposition networks operating in the region. Total reactive nitrogen deposition during the spring campaign was determined to be 0.45 kg ha -1 and more than doubled to 0.95 kg ha -1 during the summer campaign. - The reactive nitrogen deposition budget for Rocky Mountain National Park.

Restoring rocky intertidal communities: Lessons from a benthic macroalgal ecosystem engineer

International Nuclear Information System (INIS)

Bellgrove, Alecia; McKenzie, Prudence F.; Cameron, Hayley; Pocklington, Jacqueline B.

2017-01-01

As coastal population growth increases globally, effective waste management practices are required to protect biodiversity. Water authorities are under increasing pressure to reduce the impact of sewage effluent discharged into the coastal environment and restore disturbed ecosystems. We review the role of benthic macroalgae as ecosystem engineers and focus particularly on the temperate Australasian fucoid Hormosira banksii as a case study for rocky intertidal restoration efforts. Research focussing on the roles of ecosystem engineers is lagging behind restoration research of ecosystem engineers. As such, management decisions are being made without a sound understanding of the ecology of ecosystem engineers. For successful restoration of rocky intertidal shores it is important that we assess the thresholds of engineering traits (discussed herein) and the environmental conditions under which they are important. - Highlights: • Fucoid algae can be important ecosystem engineers in rocky reef ecosystems • Sewage-effluent disposal negatively affects fucoids and associated communities • Restoring fucoid populations can improve biodiversity of degraded systems • Clarifying the roles of fucoids in ecosystem function can improve restoration efforts • Thresholds of engineering traits and associated environmental conditions important

Facility overview for commercial application of selected Rocky Flats facilities

International Nuclear Information System (INIS)

1996-11-01

The purpose of this Facility Overview is to support the Rocky Flats Local Impacts Initiative's Request for Interest, to solicit interest from commercial corporations for utilizing buildings 865 and 883, and the equipment contained within each building, for a commercial venture. In the following sections, this document describes the Rocky Flats Site, the buildings available for lease, the equipment within these buildings, the site services available to a tenant, the human resources available to support operations in buildings 865 and 883, and the environmental condition of the buildings and property. In addition, a brief description is provided of the work performed to date to explore the potential products that might be manufactured in Buildings 865 and 883, and the markets for these products

Vascular plant flora of the alpine zone in the southern Rocky Mountains, U.S.A

Science.gov (United States)

James F. Fowler; B. E. Nelson; Ronald L. Hartman

2014-01-01

Field detection of changes in occurrence, distribution, or abundance of alpine plant species is predicated on knowledge of which species are in specific locations. The alpine zone of the Southern Rocky Mountain Region has been systematically inventoried by the staff and floristics graduate students from the Rocky Mountain Herbarium over the last 27 years. It is...

Low power fast settling multi-standard current reusing CMOS fractional-N frequency synthesizer

International Nuclear Information System (INIS)

Lou Wenfeng; Feng Peng; Wang Haiyong; Wu Nanjian

2012-01-01

A low power fast settling multi-standard CMOS fractional-N frequency synthesizer is proposed. The current reusing and frequency presetting techniques are adopted to realize the low power fast settling multi-standard fractional-N frequency synthesizer. An auxiliary non-volatile memory (NVM) is embedded to avoid the repetitive calibration process and to save power in practical application. This PLL is implemented in a 0.18 μm technology. The frequency range is 0.3 to 2.54 GHz and the settling time is less than 5 μs over the entire frequency range. The LC-VCO with the stacked divide-by-2 has a good figure of merit of −193.5 dBc/Hz. The measured phase noise of frequency synthesizer is about −115 dBc/Hz at 1 MHz offset when the carrier frequency is 2.4 GHz and the reference spurs are less than −52 dBc. The whole frequency synthesizer consumes only 4.35 mA and 1.8 V. (semiconductor integrated circuits)

Why sulfonamides are contraindicated in Rocky Mountain spotted fever

OpenAIRE

Ren, Vicky; Hsu, Sylvia

2014-01-01

Sulfonamide antibiotics are not effective for the treatment of Rocky Mountain spotted fever (RMSF). Patients suspected of having RMSF based on history and physical exam should be treated with doxycycline and not a sulfonamide to avoid increased morbidity and mortality.

Why sulfonamides are contraindicated in Rocky Mountain spotted fever.

Science.gov (United States)

Ren, Vicky; Hsu, Sylvia

2014-02-18

Sulfonamide antibiotics are not effective for the treatment of Rocky Mountain spotted fever (RMSF). Patients suspected of having RMSF based on history and physical exam should be treated with doxycycline and not a sulfonamide to avoid increased morbidity and mortality.

Synthetic Minor NSR Permit: Tesoro Logistics-Rockies - Ponderosa Compressor Station

Science.gov (United States)

This page contains documents related to the synthetic minor NSR permit for the Tesoro Logistics-Rockies Ponderosa Compressor Station, located on the Uintah and Ouray Indian Reservation in Uintah County, UT.

Formulation and Validation of an Efficient Computational Model for a Dilute, Settling Suspension Undergoing Rotational Mixing

Energy Technology Data Exchange (ETDEWEB)

Sprague, Michael A.; Stickel, Jonathan J.; Sitaraman, Hariswaran; Crawford, Nathan C.; Fischer, Paul F.

2017-04-11

Designing processing equipment for the mixing of settling suspensions is a challenging problem. Achieving low-cost mixing is especially difficult for the application of slowly reacting suspended solids because the cost of impeller power consumption becomes quite high due to the long reaction times (batch mode) or due to large-volume reactors (continuous mode). Further, the usual scale-up metrics for mixing, e.g., constant tip speed and constant power per volume, do not apply well for mixing of suspensions. As an alternative, computational fluid dynamics (CFD) can be useful for analyzing mixing at multiple scales and determining appropriate mixer designs and operating parameters. We developed a mixture model to describe the hydrodynamics of a settling cellulose suspension. The suspension motion is represented as a single velocity field in a computationally efficient Eulerian framework. The solids are represented by a scalar volume-fraction field that undergoes transport due to particle diffusion, settling, fluid advection, and shear stress. A settling model and a viscosity model, both functions of volume fraction, were selected to fit experimental settling and viscosity data, respectively. Simulations were performed with the open-source Nek5000 CFD program, which is based on the high-order spectral-finite-element method. Simulations were performed for the cellulose suspension undergoing mixing in a laboratory-scale vane mixer. The settled-bed heights predicted by the simulations were in semi-quantitative agreement with experimental observations. Further, the simulation results were in quantitative agreement with experimentally obtained torque and mixing-rate data, including a characteristic torque bifurcation. In future work, we plan to couple this CFD model with a reaction-kinetics model for the enzymatic digestion of cellulose, allowing us to predict enzymatic digestion performance for various mixing intensities and novel reactor designs.

SVOC partitioning between the gas phase and settled dust indoors

DEFF Research Database (Denmark)

Weschler, Charles J.; Nazaroff, W. W.

2010-01-01

Semivolatile organic compounds (SVOCs) are a major class of indoor pollutants. Understanding SVOC partitioning between the gas phase and settled dust is important for characterizing the fate of these species indoors and the pathways by which humans are exposed to them. Such knowledge also helps...

Larvae of the Commercial Tropical Oyster Crassostrea belcheri (Sowerby) are induced to settle by Pheromones from the Adults

DEFF Research Database (Denmark)

Bussarawit, Somchai; Cedhagen, Tomas

2012-01-01

Pediveliger larvae of the commercial tropical oyster Crassostrea belcheri were allowed to settle under different conditions. Two types of seawater were used for the experiments: aged seawater (1 month) and aged seawater conditioned by the presence of adult oysters for 24 hours. Two groups of five...... other species within the same genus or from a different genus. Settling frequency was increased by the presence of living oysters together with soaked spatfall collectors in commercial aquaculture. The fact that larvae are induced to settle by pheromones released from the adults is an important...... mechanism that favours the gregariousness of the oysters in nature. Settling behaviour of oyster larvae was observed and the behaviour of the three main stages was described: free swimming searching stage, crawling stage and cementing stage....

Canadian Rockies Ecoregion: Chapter 4 in Status and trends of land change in the Western United States--1973 to 2000

Science.gov (United States)

Taylor, Janis L.

2012-01-01

The Canadian Rockies Ecoregion covers approximately 18,494 km2 (7,141 mi2) in northwestern Montana (Omernik, 1987; U.S. Environmental Protection Agency, 1997). The east side of the ecoregion is bordered by the Montana Valley and Foothill Prairies Ecoregion, which also forms a large part of the western border of the ecoregion. In addition, the Northern Rockies Ecoregion wraps around the ecoregion to the northwest and south (fig. 1). As the name implies, the Canadian Rocky Mountains are located mostly in Canada, straddling the border between Alberta and British Columbia. However, this ecoregion only includes the part of the northern Rocky Mountains that is in the United States. This ecoregion is characterized by steep, high-elevation mountain ranges similar to most of the rest of the Rocky Mountains. Compared to the Northern Rockies Ecoregion, however, the Canadian Rockies Ecoregion reaches higher elevations and contains a greater proportion of perennial snow and ice (Omernik, 1987) (fig. 2). Over the years, this section of the Rocky Mountains has garnered many different names, including “Crown of the Continent” by George Bird Grinnell (Waldt, 2008) and “Backbone of the World” by the Blackfeet (Pikuni) Nation. Throughout the ecoregion, montane, subalpine, and alpine ecosystems have distinct flora and fauna elevation zones. Glaciers, permanent snowfields, and seasonal snowpack are found at the highest elevations. Spring and summer runoff fills lakes and tarns that form the headwaters of numerous streams and rivers, including the Columbia and Missouri Rivers that flow west and east, respectively, from the Continental Divide.

An Approach to Understanding Cohesive Slurry Settling, Mobilization, and Hydrogen Gas Retention in Pulsed Jet Mixed Vessels

Energy Technology Data Exchange (ETDEWEB)

Gauglitz, Phillip A.; Wells, Beric E.; Fort, James A.; Meyer, Perry A.

2009-05-22

The Hanford Waste Treatment and Immobilization Plant (WTP) is being designed and built to pretreat and vitrify a large portion of the waste in Hanford’s 177 underground waste storage tanks. Numerous process vessels will hold waste at various stages in the WTP. Some of these vessels have mixing-system requirements to maintain conditions where the accumulation of hydrogen gas stays below acceptable limits, and the mixing within the vessels is sufficient to release hydrogen gas under normal conditions and during off-normal events. Some of the WTP process streams are slurries of solid particles suspended in Newtonian fluids that behave as non-Newtonian slurries, such as Bingham yield-stress fluids. When these slurries are contained in the process vessels, the particles can settle and become progressively more concentrated toward the bottom of the vessels, depending on the effectiveness of the mixing system. One limiting behavior is a settled layer beneath a particle-free liquid layer. The settled layer, or any region with sufficiently high solids concentration, will exhibit non-Newtonian rheology where it is possible for the settled slurry to behave as a soft solid with a yield stress. In this report, these slurries are described as settling cohesive slurries.

Quantitative detection of settled coal dust over green canopy

Science.gov (United States)

Brook, Anna; Sahar, Nir

2017-04-01

The main task of environmental and geoscience applications are efficient and accurate quantitative classification of earth surfaces and spatial phenomena. In the past decade, there has been a significant interest in employing spectral unmixing in order to retrieve accurate quantitative information latent in in situ data. Recently, the ground-truth and laboratory measured spectral signatures promoted by advanced algorithms are proposed as a new path toward solving the unmixing problem in semi-supervised fashion. This study presents a practical implementation of field spectroscopy as a quantitative tool to detect settled coal dust over green canopy in free/open environment. Coal dust is a fine powdered form of coal, which is created by the crushing, grinding, and pulverizing of coal. Since the inelastic nature of coal, coal dust can be created during transportation, or by mechanically handling coal. Coal dust, categorized at silt-clay particle size, of particular concern due to heavy metals (lead, mercury, nickel, tin, cadmium, mercury, antimony, arsenic, isotopes of thorium and strontium) which are toxic also at low concentrations. This hazard exposes risk on both environment and public health. It has been identified by medical scientist around the world as causing a range of diseases and health problems, mainly heart and respiratory diseases like asthma and lung cancer. It is due to the fact that the fine invisible coal dust particles (less than 2.5 microns) long lodge in the lungs and are not naturally expelled, so long-term exposure increases the risk of health problems. Numerus studies reported that data to conduct study of geographic distribution of the very fine coal dust (smaller than PM 2.5) and related health impacts from coal exports, is not being collected. Sediment dust load in an indoor environment can be spectrally assessed using reflectance spectroscopy (Chudnovsky and Ben-Dor, 2009). Small amounts of particulate pollution that may carry a signature

Analysis of sludge from Hanford K East Basin canisters

Energy Technology Data Exchange (ETDEWEB)

Makenas, B.J. [ed.] [comp.] [DE and S Hanford, Inc., Richland, WA (United States); Welsh, T.L. [B and W Protec, Inc. (United States); Baker, R.B. [DE and S Hanford, Inc., Richland, WA (United States); Hoppe, E.W.; Schmidt, A.J.; Abrefah, J.; Tingey, J.M.; Bredt, P.R.; Golcar, G.R. [Pacific Northwest National Lab., Richland, WA (United States)

1997-09-12

Sludge samples from the canisters in the Hanford K East Basin fuel storage pool have been retrieved and analyzed. Both chemical and physical properties have been determined. The results are to be used to determine the disposition of the bulk of the sludge and to assess the impact of residual sludge on dry storage of the associated intact metallic uranium fuel elements. This report is a summary and review of the data provided by various laboratories. Although raw chemistry data were originally reported on various bases (compositions for as-settled, centrifuged, or dry sludge) this report places all of the data on a common comparable basis. Data were evaluated for internal consistency and consistency with respect to the governing sample analysis plan. Conclusions applicable to sludge disposition and spent fuel storage are drawn where possible.

Basic TRUEX process for Rocky Flats Plant

International Nuclear Information System (INIS)

Leonard, R.A.; Chamberlain, D.B.; Dow, J.A.; Farley, S.E.; Nunez, L.; Regalbuto, M.C.; Vandegrift, G.F.

1994-08-01

The Generic TRUEX Model was used to develop a TRUEX process flowsheet for recovering the transuranics (Pu, Am) from a nitrate waste stream at Rocky Flats Plant. The process was designed so that it is relatively insensitive to changes in process feed concentrations and flow rates. Related issues are considered, including solvent losses, feed analysis requirements, safety, and interaction with an evaporator system for nitric acid recycle

Association analysis of PRNP gene region with chronic wasting disease in Rocky Mountain elk

Directory of Open Access Journals (Sweden)

Spraker Terry R

2010-11-01

Full Text Available Abstract Background Chronic wasting disease (CWD is a transmissible spongiform encephalopathy (TSE of cervids including white-tailed (Odocoileus virginianus and mule deer (Odocoileus hemionus, Rocky Mountain elk (Cervus elaphus nelsoni, and moose (Alces alces. A leucine variant at position 132 (132L in prion protein of Rocky Mountain elk confers a long incubation time with CWD, but not complete resistance. However, variants in regulatory regions outside the open reading frame of PRNP have been associated with varying degrees of susceptibility to prion disease in other species, and some variants have been observed in similar regions of Rocky Mountain elk PRNP. Thus, additional genetic variants might provide increased protection, either alone or in combination with 132L. Findings This study provided genomic sequence of all exons for PRNP of Rocky Mountain elk. Many functional sites in and around the PRNP gene region were sequenced, and this report approximately doubled (to 75 the number of known variants in this region. A haplotype-tagging approach was used to reduce the number of genetic variants required to survey this variation in the PRNP gene region of 559 Rocky Mountain elk. Eight haplotypes were observed with frequencies over 1.0%, and one haplotype was present at 71.2% frequency, reflecting limited genetic diversity in the PRNP gene region. Conclusions The presence of 132L cut odds of CWD by more than half (Odds Ratio = 0.43; P = 0.0031, which was similar to a previous report. However after accounting for 132L, no association with CWD was found for any additional variants in the PRNP region (P > 0.05.

Long-term effects of Exxon Valdez oiling and shoreline treatments on rocky intertidal epibiota

International Nuclear Information System (INIS)

Houghton, J.P.; Fukuyama, A.K.; Lees, D.C.; Driskell, W.B.; Shigenaka, G.; Mearns, A.J.

1993-01-01

Hot-water treatments used to remove Exxon Valdez oil from rocky beaches of Prince William Sound in 1989 were shown to have severe short-term impacts on intertidal epibenthos. Quantitative sampling was conducted from 1989 through 1993 to evaluate recovery of littoral habitats from the effects of oiling and hotwater washing. Effects of hot-water treatments applied in 1989 remained visible in intertidal assemblages through 1993. Some hot-water treated rocky shores that had been stripped of biota showed little colonization by 1991; significant differences remained between epibiota on unoiled shores and that on oiled shores that were hot-water washed. On other oiled rocky shores that were not hot-water washed, the majority of the community dominants, including rockweed, mussels, barnacles, limpets, drills, and littorines, survived the oiling; by July 1991 these shores did not differ in most respects from unoiled shores. By July 1993 hot-water-washed rocky shores had been colonized by opportunistic species as well as by most of the original biota. Algal assemblages were heavily dominated by rockweed, but red algae reminded depressed, especially at lower elevations; otherwise, few significant differences remained in 1993 between the epibiota on unoiled and hot-water-washed shores. Full recovery appears to be several years away in many areas, however

A history of forest entomology in the Intermountain and Rocky Mountain areas, 1901 to 1982

Science.gov (United States)

Malcolm M. Furniss

2007-01-01

This account spans the time from A.D. Hopkins' trip to the Black Hills, SD, in 1901 to my retirement in 1982. The focus is on personnel and the work of the Division of Forest Insect Investigations, USDA, and the Forest Service experiment stations in the Rocky Mountain and Intermountain areas. Information for the Intermountain and Northern Rocky Mountain station...

Co-Infection of Rickettsia rickettsii and Streptococcus pyogenes: Is Fatal Rocky Mountain Spotted Fever Underdiagnosed?

Science.gov (United States)

Raczniak, Gregory A.; Kato, Cecilia; Chung, Ida H.; Austin, Amy; McQuiston, Jennifer H.; Weis, Erica; Levy, Craig; Carvalho, Maria da Gloria S.; Mitchell, Audrey; Bjork, Adam; Regan, Joanna J.

2014-01-01

Rocky Mountain spotted fever, a tick-borne disease caused by Rickettsia rickettsii, is challenging to diagnose and rapidly fatal if not treated. We describe a decedent who was co-infected with group A β-hemolytic streptococcus and R. rickettsii. Fatal cases of Rocky Mountain spotted fever may be underreported because they present as difficult to diagnose co-infections. PMID:25331804

Conceptual plan for 100-N Emergency Dump Basin (EDB) deactivation

International Nuclear Information System (INIS)

Davis, C.M.; Day, R.S.; Smith, D.L.

1996-07-01

This document provides the conceptual plan for the 100-N Emergency Dump Basin (EDB) located at the Hanford Site in Richland, Washington. The EDB is an outdoor concrete retention pond with a carbon-steel liner underlain with fiberglass. The EDB was originally designed as a quenching pool for reactor blowdown in event of a primary coolant leak. However, the EDB only received routine steam-generator blowdowns from 1963 to 1987. The steam-generator blowdown and leaking isolation valves allowed radioactively contaminated water (from primary and secondary reactor coolant leaks) to enter the EDB. Over the years, wind-blown sand and dust have settled in the EDB, resulting in the present layer of sediments. As of February 1996, the EDB contained an estimated 260,000 gal of water and approximately 2,300 ft3 of sediment. The average sediment thickness is estimated at 2.5 ft and is covered with approximately 12 ft to 14 ft of water. Vegetation (mostly reeds and cattails) grows in the basin corners where the sediment is exposed. To minimize animal and bird intrusion, a kneeling net has been installed over the EDB

Characterization of Most Promising Sequestration Formations in the Rocky Mountain Region (RMCCS)

Energy Technology Data Exchange (ETDEWEB)

McPherson, Brian; Matthews, Vince

2013-09-30

The primary objective of the “Characterization of Most Promising Carbon Capture and Sequestration Formations in the Central Rocky Mountain Region” project, or RMCCS project, is to characterize the storage potential of the most promising geologic sequestration formations within the southwestern U.S. and the Central Rocky Mountain region in particular. The approach included an analysis of geologic sequestration formations under the Craig Power Station in northwestern Colorado, and application or extrapolation of those local-scale results to the broader region. A ten-step protocol for geologic carbon storage site characterization was a primary outcome of this project.

Rocky Flats Neutron Detector Testing at Valduc, France

International Nuclear Information System (INIS)

Kim, S.S.; Dulik, G.M.

2011-01-01

Recent program requirements of the US Department of Energy/NNSA have led to a need for a criticality accident alarm system to be installed at a newly activated facility. The Criticality Safety Group of the Lawrence Livermore National Laboratory (LLNL) was able to recover and store for possible future use approximately 200 neutron criticality detectors and 20 master alarm panels from the former Rocky Flats Plant in Golden, Colorado when the plant was closed. The Criticality Safety Group participated in a facility analysis and evaluation, the engineering design and review process, as well as the refurbishment, testing, and recalibration of the Rocky Flats criticality alarm system equipment to be used in the new facility. In order to demonstrate the functionality and survivability of the neutron detectors to the effects of an actual criticality accident, neutron detector testing was performed at the French CEA Valduc SILENE reactor from October 7 to October 19, 2010. The neutron detectors were exposed to three criticality events or pulses generated by the SILENE reactor. The first excursion was performed with a bare or unshielded reactor, and the second excursion was made with a lead shielded/reflected reactor, and the third excursion with a polyethylene reflected core. These tests of the Rocky Flats neutron detectors were performed as a part of the 2010 Criticality Accident Alarm System Benchmark Measurements at the SILENE Reactor. The principal investigators for this series of experiments were Thomas M. Miller and John C. Wagner of the Oak Ridge National Laboratory, with Nicolas Authier and Nathalie Baclet of CEA Valduc. Several other organizations were also represented, including the Y-12 National Security Complex, Lawrence Livermore National Laboratory, Los Alamos National Laboratory, CEA Saclay, and Babcock International Group.

Self-reported treatment practices by healthcare providers could lead to death from Rocky Mountain spotted fever.

Science.gov (United States)

Zientek, Jillian; Dahlgren, F Scott; McQuiston, Jennifer H; Regan, Joanna

2014-02-01

Among 2012 Docstyle survey respondents, 80% identified doxycycline as the appropriate treatment for Rocky Mountain spotted fever in patients ≥ 8 years old, but only 35% correctly chose doxycycline in patients Rocky Mountain spotted fever observed nationally. Targeted education efforts are needed. Crown Copyright © 2014. Published by Mosby, Inc. All rights reserved.

On time discretizations for the simulation of the batch settling-compression process in one dimension.

Science.gov (United States)

Bürger, Raimund; Diehl, Stefan; Mejías, Camilo

2016-01-01

The main purpose of the recently introduced Bürger-Diehl simulation model for secondary settling tanks was to resolve spatial discretization problems when both hindered settling and the phenomena of compression and dispersion are included. Straightforward time integration unfortunately means long computational times. The next step in the development is to introduce and investigate time-integration methods for more efficient simulations, but where other aspects such as implementation complexity and robustness are equally considered. This is done for batch settling simulations. The key findings are partly a new time-discretization method and partly its comparison with other specially tailored and standard methods. Several advantages and disadvantages for each method are given. One conclusion is that the new linearly implicit method is easier to implement than another one (semi-implicit method), but less efficient based on two types of batch sedimentation tests.

Polymer solidification of mixed wastes at the Rocky Flats Plant

International Nuclear Information System (INIS)

Faucette, A.M.; Logsdon, B.W.; Lucerna, J.J.; Yudnich, R.J.

1994-01-01

The Rocky Flats Plant is pursuing polymer solidification as a viable treatment option for several mixed waste streams that are subject to land disposal restrictions within the Resource Conservation and Recovery Act provisions. Tests completed to date using both surrogate and actual wastes indicate that polyethylene microencapsulation is a viable treatment option for several mixed wastes at the Rocky Flats Plant, including nitrate salts, sludges, and secondary wastes such as ash. Treatability studies conducted on actual salt waste demonstrated that the process is capable of producing waste forms that comply with all applicable regulatory criteria, including the Toxicity Characteristic Leaching Procedure. Tests have also been conducted to evaluate the feasibility of macroencapsulating certain debris wastes in polymers. Several methods and plastics have been tested for macroencapsulation, including post-consumer recycle and regrind polyethylene

The role of macrobiota in structuring microbial communities along rocky shores

Directory of Open Access Journals (Sweden)

Catherine A. Pfister

2014-10-01

Full Text Available Rocky shore microbial diversity presents an excellent system to test for microbial habitat specificity or generality, enabling us to decipher how common macrobiota shape microbial community structure. At two coastal locations in the northeast Pacific Ocean, we show that microbial composition was significantly different between inert surfaces, the biogenic surfaces that included rocky shore animals and an alga, and the water column plankton. While all sampled entities had a core of common OTUs, rare OTUs drove differences among biotic and abiotic substrates. For the mussel Mytilus californianus, the shell surface harbored greater alpha diversity compared to internal tissues of the gill and siphon. Strikingly, a 7-year experimental removal of this mussel from tidepools did not significantly alter the microbial community structure of microbes associated with inert surfaces when compared with unmanipulated tidepools. However, bacterial taxa associated with nitrate reduction had greater relative abundance with mussels present, suggesting an impact of increased animal-derived nitrogen on a subset of microbial metabolism. Because the presence of mussels did not affect the structure and diversity of the microbial community on adjacent inert substrates, microbes in this rocky shore environment may be predominantly affected through direct physical association with macrobiota.

Quantitative respirator man-testing at Rocky Flats

Energy Technology Data Exchange (ETDEWEB)

Leigh, J. D.

1978-01-01

The dioctyl phthalate quantitative respirator man-testing method used at Rocky Flats is outlined. Using this method, 93 persons trained to use self contained breathing equipment were tested with eight respiratory protective devices. Test results obtained with the seven devices using high efficiency particulate filters are compared to the results obtained with the self contained breathing equipment. Also comparison is made for these results to test results for 1667 other employees.

Quantitative respirator man-testing at Rocky Flats

International Nuclear Information System (INIS)

Leigh, J.D.

The dioctyl phthalate quantitative respirator man-testing method used at Rocky Flats is outlined. Using this method, 93 persons trained to use self contained breathing equipment were tested with eight respiratory protective devices. Test results obtained with the seven devices using high efficiency particulate filters are compared to the results obtained with the self contained breathing equipment. Also comparison is made for these results to test results for 1667 other employees

[A fatal case series of Rocky Mountain spotted fever in Sonora, México].

Science.gov (United States)

Delgado-De la Mora, Jesús; Licona-Enríquez, Jesús David; Leyva-Gastélum, Marcia; Delgado-De la Mora, David; Rascón-Alcantar, Adela; Álvarez-Hernández, Gerardo

2018-03-15

Rocky Mountain spotted fever is a highly lethal infectious disease, particularly if specific treatment with doxycycline is given belatedly. To describe the clinical profile of fatal Rocky Mountain spotted fever cases in hospitalized patients in the state of Sonora, México. We conducted a cross-sectional study on a series of 47 deaths caused by Rickettsia rickettsii from 2013 to 2016. The diagnosis of Rocky Mountain spotted fever was confirmed in a single blood sample by polymerase chain reaction (PCR) or by a four-fold increase in immunoglobulin G measured in paired samples analyzed by indirect immunofluorescence. Clinical and laboratory characteristics were compared stratifying subjects into two groups: pediatric and adult. There were no differences in clinical characteristics between groups; petechial rash was the most frequent sign (96%), followed by headache (70%) and myalgia (67%). Although that doxycycline was administered before the fifth day from the onset of symptoms, death occurred in 55% of patients. In clinical laboratory, thrombocytopenia, and biomarkers of liver acute failure and acute kidney failure were the most frequent. Rocky Mountain spotted fever remains as one of the most lethal infectious diseases, which may be related not only to the lack of diagnostic suspicion and delayed administration of doxycycline, but to genotypic characteristics of Rickettsia rickettsii that may play a role in the variability of the fatality rate that has been reported in other geographical regions where the disease is endemic.

Rocky Flats Plant Site Environmental Report for 1992

International Nuclear Information System (INIS)

Cirrincione, D.A.; Erdmann, N.L.

1992-01-01

The Rocky Rats Plant Site Environmental Report provides summary information on the plant's environmental monitoring programs and the results recorded during 1992. The report contains a compliance summary, results of environmental monitoring and other related programs, a review of environmental remediation activities, information on external gamma radiation dose monitoring, and radiation dose estimates for the surrounding population

Rocky Flats Plant Site Environmental Report for 1992

Energy Technology Data Exchange (ETDEWEB)

Cirrincione, D.A.; Erdmann, N.L. [eds.

1992-12-31

The Rocky Rats Plant Site Environmental Report provides summary information on the plant`s environmental monitoring programs and the results recorded during 1992. The report contains a compliance summary, results of environmental monitoring and other related programs, a review of environmental remediation activities, information on external gamma radiation dose monitoring, and radiation dose estimates for the surrounding population.

Natural phenomena risk assessment at Rocky Flats Plant

International Nuclear Information System (INIS)

Foppe, T.L.

1985-01-01

A realistic approach is currently being used at the Rocky Flats Plant to assess the risks of natural phenomena events. The methodology addresses frequency of occurrence estimates, damage stress on the facility and vital equipment, material-at-risk, release fractions and source terms, leakpath, dispersion and dosimetric models, risk curves, and an uncertainty analysis. 28 references, 1 figure

Erratum: Vascular epiphyte vegetation in rocky savannas of southeastern Brazil

Czech Academy of Sciences Publication Activity Database

Alves, R. J. V.; Kolbek, Jiří; Becker, J.

2009-01-01

Roč. 27, č. 4 (2009), s. 351-352 ISSN 0107-055X Institutional research plan: CEZ:AV0Z60050516 Keywords : epiphytes * Brazil * rocky savannas Subject RIV: EF - Botanics Impact factor: 0.868, year: 2009

[Leaf nitrogen and phosphorus stoichiometry of shrubland plants in the rocky desertification area of Southwestern Hunan, China.

Science.gov (United States)

Jing, Yi Ran; Deng, Xiang Wen; Wei, Hui; Li, Yan Qiong; Deng, Dong Hua; Liu, Hao Jian; Xiang, Wen Hua

2017-02-01

In this paper, we took the leaves of shrubland plants in rocky desertification area in Southwestern Hunan as the research object to analyze the nitrogen (N) and phosphorus (P) stoichiometry characteristics for different functional groups and different grades of rocky desertification, i.e., light rocky desertification (LRD), moderate rocky desertification (MRD) and intense rocky desertification (IRD). The results showed that the average contents of N and P were 12.89 and 1.19 g·kg -1 , respectively, and N/P was 11.24 in common shrubland plants in the study area, which indicated that the growth of most plants were mainly limited by N. The content of N was declined in order of deciduous shrubs > evergreen shrubs > annual herbs > perennial herbs. The content of P and N/P were higher in deciduous shrubs than in perennial herbs. Significant differences were found among the main families of plants in terms of the contents of N, P and N/P in the study sites. The plants of Gramineae had the lowest contents of N and P, andtheir growth was mostly restricted by N, while Leguminosae had the highest content of N and N/P, and their productivity was majorly controlled by P. The contents of N and P in the leaves were significantly higher in dicotyledon plants and C3 plants than in monocotyledon plants and C4 plants, but the N/P was not significantly diffe-rent between these two plant categories. The nitrogen-fixing plants had higher content of N and N/P than the non-nitrogen-fixing plants, but the P content was not significantly different between these two plant groups. There were significant correlations between contents of N and P, N/P and N in all study plots. No significant correlation was found between N/P and P content in the examined rocky desertification sites, except for that in MRD. There were no significant differences of the contents of N, P and N/P under different grades of rocky desertification.

Atmospheric dispersion modeling at the Rocky Flats Plant. Progress report, December 1981-December 1985

International Nuclear Information System (INIS)

Hodgin, C.R.

1986-01-01

The Rocky Flats Plant applies atmospheric dispersion modeling as a tool for Emergency Response, Risk Assessment, and Regulatory Compliance. Extreme variations in terrain around the facility have necessitated the development of an advanced modeling approach. The Terrain-Responsive Atmospheric Code (TRAC) was developed to treat realistically the changing wind, stability, dispersion, and deposition patterns that are experienced in mountainous areas. The result is a detailed picture of dose and deposition patterns associated with postulated or actual releases. A unified approach was taken to modeling needs at Rocky Flats. This produces consistent dose projections for all applications. A Risk Assessment version of TRAC is now operational. A high-speed version of the code is being implemented for Emergency Response, and development of a regulatory version is under way. Public, scientific, and governmental acceptance of TRAC is critical to successful applications at the Rocky Flats Plant. A program of peer review and regulatory approval was initiated to provide a full outside evaluation of our techniques. Full field validation (tracer testing) is key to demonstrating reliability of the TRAC model. A validation study was planned for implementation beginning in early CY-1986. The necessary funding ($500,000) is being sought. Although the TRAC model development and approval program was developed for site-specific needs at the Rocky Flats Plant, potential exists for wider application within the Department of Energy (DOE). The TRAC model can be easily applied at other sites in complex terrain. A coordinated approach to model validation throughout the Albquerque Operations Office (AL) or DOE complexes could prove more cost effective than site-by-site evaluations. Finally, the model approval procedure developed jointly by Rocky Flats and the Environmental Protection Agency (EPA) is general and could be applied to other models or as the basis for a DOE-wide program

Adult Onset Still's Disease and Rocky Mountain Spotted Fever

Directory of Open Access Journals (Sweden)

Paul Persad

2010-01-01

Full Text Available Adult Still's Disease was first described in 1971 by Bywaters in fourteen adult female patients who presented with symptoms indistinguishable from that of classic childhood Still's Disease (Bywaters, 1971. George Still in 1896 first recognized this triad of quotidian (daily fevers, evanescent rash, and arthritis in children with what later became known as juvenile inflammatory arthritis (Still, 1990. Adult Onset Still's Disease (AOSD is an inflammatory condition of unknown etiology characterized by an evanescent rash, quotidian fevers, and arthralgias. Numerous infectious agents have been associated with its presentation. This case is to our knowledge the first presentation of AOSD in the setting of Rocky Mountain Spotted Fever. Although numerous infectious agents have been suggested, the etiology of this disorder remains elusive. Nevertheless, infection may in fact play a role in triggering the onset of symptoms in those with this disorder. Our case presentation is, to our knowledge, the first case of Adult Onset Still's Disease associated with Rocky Mountain spotted fever (RMSF.

Thermal Structure and Mantle Dynamics of Rocky Exoplanets

Science.gov (United States)

Wagner, F. W.; Tosi, N.; Hussmann, H.; Sohl, F.

2011-12-01

The confirmed detections of CoRoT-7b and Kepler-10b reveal that rocky exoplanets exist. Moreover, recent theoretical studies suggest that small planets beyond the Solar System are indeed common and many of them will be discovered by increasingly precise observational surveys in the years ahead. The knowledge about the interior structure and thermal state of exoplanet interiors provides crucial theoretical input not only for classification and characterization of individual planetary bodies, but also to better understand the origin and evolution of the Solar System and the Earth in general. These developments and considerations have motivated us to address several questions concerning thermal structure and interior dynamics of terrestrial exoplanets. In the present study, depth-dependent structural models of solid exoplanet interiors have been constructed in conjunction with a mixing length approach to calculate self-consistently the radial distribution of temperature and heat flux. Furthermore, 2-D convection simulations using the compressible anelastic approximation have been carried through to examine the effect of thermodynamic quantities (e.g., thermal expansivity) on mantle convection pattern within rocky planets more massive than the Earth. In comparison to parameterized convection models, our calculated results predict generally hotter planetary interiors, which are mainly attributed to a viscosity-regulating feedback mechanism involving temperature and pressure. We find that density and thermal conductivity increase with depth by a factor of two to three, however, thermal expansivity decreases by more than an order of magnitude across the mantle for planets as massive as CoRoT-7b or Kepler-10b. The specific heat capacity is observed to stay almost constant over an extended region of the lower mantle. The planform of mantle convection is strongly modified in the presence of depth-dependent thermodynamic quantities with hot upwellings (plumes) rising across

Rocky flats community relations open-quotes coming out of the darkclose quotes

International Nuclear Information System (INIS)

Lockhart, F.R.

1991-01-01

Community relations is becoming an increasingly prominent aspect of the environmental restoration business. Historically the DOE has been closed to public scrutiny, dating back to the origins of the weapons complex in the Manhattan Project. Rocky Flats community relations can be viewed as having its painful start on June 6, 1989, when over fifty FBI agents entered Rocky Flats to gather information on alleged operational and procedural violations of environmental law. The Plutonium Recovery Modification Project (PRMP) was the first initiative to hold public meetings and provide for real dialogue in May 1990. Building on this start, the last year has seen a phenomenal growth of Rocky Flats community relations activities, now averaging over one public forum of some kind per week. We believe the effort has been very successful in building understanding and credibility within the local community. Although community relations is not a panacea, neither is it an ogre. Community relations for environmental restoration is mandated by law, and for good management is a necessary part of the DOE for the 1990's and beyond. Properly utilized, it can augment an ongoing environmental program and help smooth the road to success

Evaluation Of Hydraulic Potentiality For The Generation Of Hydroelectric To Small Scale In The Basin Of The CHICAMOCHA River - Small Hydroelectric Centrals

International Nuclear Information System (INIS)

Pacheco P, Claudia M.; Parga C, Gloria M.

1995-01-01

In development of the agreement of technical and scientific cooperation established between the INEA and the Catholic University of Colombia, the program of Evaluation of Hydraulic Potentiality for Small Central was developed, whose purpose is to take the service to smaller population and villages of all the towns of the country. To begin the program the area corresponding to the basin of Chicamocha river was selected, since this region that corresponds to 72 towns of Boyaca and Santander, has good information, thanks to the diagnosis carried out by the Inderena with the purpose of formulating a Plan of Classification and Handling of the Basin. The work consisted on the identification of all the micro basins, the analysis of the demand of energy of the settled population, to evaluate the generating capacity of the flows of water and, according to the results, to propose alternatives for the design of small hydroelectric centrals (PCH) in accordance with the needs

Small theropod teeth from the Late Cretaceous of the San Juan Basin, northwestern New Mexico and their implications for understanding latest Cretaceous dinosaur evolution.

Science.gov (United States)

Williamson, Thomas E; Brusatte, Stephen L

2014-01-01

Studying the evolution and biogeographic distribution of dinosaurs during the latest Cretaceous is critical for better understanding the end-Cretaceous extinction event that killed off all non-avian dinosaurs. Western North America contains among the best records of Late Cretaceous terrestrial vertebrates in the world, but is biased against small-bodied dinosaurs. Isolated teeth are the primary evidence for understanding the diversity and evolution of small-bodied theropod dinosaurs during the Late Cretaceous, but few such specimens have been well documented from outside of the northern Rockies, making it difficult to assess Late Cretaceous dinosaur diversity and biogeographic patterns. We describe small theropod teeth from the San Juan Basin of northwestern New Mexico. These specimens were collected from strata spanning Santonian - Maastrichtian. We grouped isolated theropod teeth into several morphotypes, which we assigned to higher-level theropod clades based on possession of phylogenetic synapomorphies. We then used principal components analysis and discriminant function analyses to gauge whether the San Juan Basin teeth overlap with, or are quantitatively distinct from, similar tooth morphotypes from other geographic areas. The San Juan Basin contains a diverse record of small theropods. Late Campanian assemblages differ from approximately coeval assemblages of the northern Rockies in being less diverse with only rare representatives of troodontids and a Dromaeosaurus-like taxon. We also provide evidence that erect and recurved morphs of a Richardoestesia-like taxon represent a single heterodont species. A late Maastrichtian assemblage is dominated by a distinct troodontid. The differences between northern and southern faunas based on isolated theropod teeth provide evidence for provinciality in the late Campanian and the late Maastrichtian of North America. However, there is no indication that major components of small-bodied theropod diversity were lost

Hydrodynamics of a continuous vertical settling tank of the plate type with separation of extractive emulsions

International Nuclear Information System (INIS)

Muratov, V.M.; Lyubimov, V.K.; Rakovets, S.M.; Kucharina, G.G.

1987-01-01

The authors present the results of an investigation of the continuous process of separation of extractive emulsion in a long vertical plate-like settling tank used in mixing-settling extractors. The object of study consisted of a section of the mixer-settler with pulsational mixing and a platelike settler 60 mm wide, 1000 mm long, and 300 mm high, made of acrylic plastic. The setup was used to demonstrate the circulation of each of the reagents (phases) in its own contour; they were injected into the mixing chamber by submersible centrifugal pumps, one placed in the volume with the light phase and the other in the volume with the heavy phase. After separation in the settling tank the liquid phases were each continuously poured into their own volume

Settling fluxes and ecotoxicological risk assessment of fine sedimentary metals in Tema Harbour (Ghana).

Science.gov (United States)

Botwe, Benjamin O; Nyarko, Elvis; Lens, Piet N L

2018-01-01

Sediment traps were deployed in the Tema Harbour to estimate the settling fluxes of silt-clay particles and associated metals (Fe, Mn, Pb, Cr, Cu, Zn, Ni, Hg, Sn and As) and characterise their potential ecotoxicological risks. The mean daily settling fluxes of the silt-clay particles and associated metals ranged from 42.7 to 85.0gm -2 d -1 and 1.3×10 -2 to 49.4mgm -2 d -1 , respectively, and were characterised by large fluctuations at each station. The silt-clay and metal fluxes strongly correlated, indicating the important role of the silt-clay particles in metal transport and distribution in the harbour. Geochemical indices indicated anthropogenic influences on the harbour as the Pb, Cr, Zn, Hg, Sn and As content in the settling silt-clay particles exceeded their average crustal concentrations. Sediment quality guidelines indicated these metals pose appreciable ecotoxicological risks, particularly As. Increasing temporal trends in As necessitates increased pollution control efforts at the harbour. Copyright © 2017 Elsevier Ltd. All rights reserved.

Wind energy resource atlas. Volume 8. The southern Rocky Mountain region

Energy Technology Data Exchange (ETDEWEB)

Andersen, S.R.; Freeman, D.L.; Hadley, D.L.; Elliott, D.L.; Barchet, W.R.; George, R.L.

1981-03-01

The Southern Rocky Mountain atlas assimilates five collections of wind resource data: one for the region and one for each of the four states that compose the Southern Rocky Mountain region (Arizona, Colorado, New Mexico, and Utah). At the state level, features of the climate, topography and wind resource are discussed in greater detail than is provided in the regional discussion, and the data locations on which the assessment is based are mapped. Variations, over several time scales, in the wind resource at selected stations in each state are shown on graphs of monthly average and interannual wind speed and power, and hourly average wind speed for each season. Other graphs present speed, direction, and duration frequencies of the wind at these locations.

Bat population monitoring and conservation at the Rocky Mountain Arsenal NWR

Data.gov (United States)

Department of the Interior — A study of the bat populations at Rocky Mountain Arsenal National Wildlife Refuge (RMA) was conducted from 1997–1998, which provided basic population and contaminant...

Adsorption study for uranium in Rocky Flats groundwater

International Nuclear Information System (INIS)

Laul, J.C.; Rupert, M.C.; Harris, M.J.; Duran, A.

1995-01-01

Six adsorbents were studied to determine their effectiveness in removing uranium in Rocky Flats groundwater. The bench column and batch (Kd) tests showed that uranium can be removed (>99.9%) by four adsorbents. Bone Charcoal (R1O22); F-1 Alumina (granular activated alumina); BIOFIX (immobilized biological agent); SOPBPLUS (mixed metal oxide); Filtrasorb 300 (granular activated carbon); and Zeolite (clinoptilolite)

Comparing Fear of Death of the Elderly Settled in Elderly’s Home and Inhabited in City Houses of Isfahan

Directory of Open Access Journals (Sweden)

Esmat Nouhi

2014-01-01

Full Text Available Objectives: On the one hand, increased growth of the elderly population and on the other hand, social– economic changes, personal and family lifestyles have caused an increased number of the elderly protecting centres. The aim of the present survey is to compare the fear of death among the elderly settled in elderly home and inhabited in city houses of Isfahan. Methods & Materials: This study is an analysis – cross sectional study and statistical population are all of the elderly over 60 years inhabited in 14 – fold zones of Isfahan and the ones settled in Sadeghieh elderly home. Participants in this survey were 300 elderly people that 102 people settled in the elderly home (31 males and 71 females and 198 people inhabited in the community (97 males and 101 females. The elderly inhabited in the community were selected through a cluster sampling method and the ones settled in the elderly home through available sampling method and evaluated through a questionnaire of Collett-Lester Fear of Death. In order to analyse collected data, parametric statistical methods of K–Square test and independent–T have been used . Results: The finding of this survey showed that fear of death total score mean was 70.5±15.5 in the elderly group inhabited in houses that significantly was more than that the elderly group settled in the elderly home (P=0.001. Conclusion: The results of this survey showed that fear of death in the elderly group settled in city houses is higher than elderly settled in the elderly’s home. It is necessary that the authorities pay more attention to the sanitary systems in all levels, evaluate the causes and, try to get the aids of the relevant organizations in order to Reduced fear of death of elderly people.

Decontamination technology of contaminated water with flocculating and settling technology

International Nuclear Information System (INIS)

Aritomi, Masanori; Adachi, Toshihiro; Watanabe, Noriyuki; Hosobuchi, Shigeki

2012-01-01

In the joint research and development of treatment systems of cooling water for cutting asphalt pavement surface with our authors' group, the liquid-solid separation technology by flocculating and settling technology, and the flocculants for the use of systems were developed. In this paper, the developed flocculating and settling technology and the flocculants are discussed first. Next, the demonstration tests of decontamination technology on the contaminated water in swimming pools in an elementary school located at Motomiya City, Fukushima Prefecture had been conducted by use of the stationary purification system of contaminated water and the flocculants compounding with or without iron ferrocianide developed by the preliminary test. It was clarified from the results that ionized cesium (Cs) rarely exists in the stagnant water in pools, ponds, lakes and so on at the time when nine months have passed since Fukushima Dai-ichi nuclear power plant accidents. Further, it is necessary to use the flocculants compounding iron ferrocianide in the case where ionized Cs exists in water. From the above-mentioned results, the following problems were pointed out: One problem was cyanide dissolution in the purified water and the other one was the dissolution from the dehydration sludge. Finally, the high-performance mobile purification units of contaminated water which is capable for carrying with trucks have been developed, and the demonstration test was performed in Minami-soma City, Fukushima Prefecture to purify the contaminated water in a pond and generated by the high-pressure water washing in a Public Hall. From the test results, it was made clear that the dehydration sludge separated by liquid-solid settling of the contaminated water of around 1,000Bq/l became a high radiation dose of about 185,000Bq/l. (author)

A consistent modelling methodology for secondary settling tanks in wastewater treatment.

Science.gov (United States)

Bürger, Raimund; Diehl, Stefan; Nopens, Ingmar

2011-03-01

The aim of this contribution is partly to build consensus on a consistent modelling methodology (CMM) of complex real processes in wastewater treatment by combining classical concepts with results from applied mathematics, and partly to apply it to the clarification-thickening process in the secondary settling tank. In the CMM, the real process should be approximated by a mathematical model (process model; ordinary or partial differential equation (ODE or PDE)), which in turn is approximated by a simulation model (numerical method) implemented on a computer. These steps have often not been carried out in a correct way. The secondary settling tank was chosen as a case since this is one of the most complex processes in a wastewater treatment plant and simulation models developed decades ago have no guarantee of satisfying fundamental mathematical and physical properties. Nevertheless, such methods are still used in commercial tools to date. This particularly becomes of interest as the state-of-the-art practice is moving towards plant-wide modelling. Then all submodels interact and errors propagate through the model and severely hamper any calibration effort and, hence, the predictive purpose of the model. The CMM is described by applying it first to a simple conversion process in the biological reactor yielding an ODE solver, and then to the solid-liquid separation in the secondary settling tank, yielding a PDE solver. Time has come to incorporate established mathematical techniques into environmental engineering, and wastewater treatment modelling in particular, and to use proven reliable and consistent simulation models. Copyright © 2011 Elsevier Ltd. All rights reserved.

Finding of no significant impact. Consolidation and interim storage of special nuclear material at Rocky Flats Environmental Technology Site

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-06-01

The Department of Energy (DOE) has prepared an environmental assessment (EA), DOE/EA -- 1060, for the consolidation, processing, and interim storage of Category I and II special nuclear material (SNM) in Building 371 at the Rocky Flats Environmental Technology Site (hereinafter referred to as Rocky Flats or Site), Golden, Colorado. The scope of the EA included alternatives for interim storage including the no action alternative, the construction of a new facility for interim storage at Rocky Flats, and shipment to other DOE facilities for interim storage.

Finding of no significant impact. Consolidation and interim storage of special nuclear material at Rocky Flats Environmental Technology Site

International Nuclear Information System (INIS)

1995-06-01

The Department of Energy (DOE) has prepared an environmental assessment (EA), DOE/EA -- 1060, for the consolidation, processing, and interim storage of Category I and II special nuclear material (SNM) in Building 371 at the Rocky Flats Environmental Technology Site (hereinafter referred to as Rocky Flats or Site), Golden, Colorado. The scope of the EA included alternatives for interim storage including the no action alternative, the construction of a new facility for interim storage at Rocky Flats, and shipment to other DOE facilities for interim storage

The formation of early settled villages and the emergence of leadership: A test of three theoretical models in the Rio Ilave, Lake Titicaca Basin, southern Peru

Science.gov (United States)

Craig, Nathan Mcdonald

Despite obvious necessities for understanding later developments in the region, Preceramic cultures in the Titicaca Basin are poorly understood due to lacking empirical data. This dissertation focuses on examination of two processes occurring in the Rio Ilave drainage during the Late 5000--3100 B.C.E. (6000--4400 B.P.) and Terminal 3100--1500 B.C.E. Archaic (4400--3200 B.P.): the formation of settled villages and the emergence of leadership. These processes are tested against theoretical predictions derived from: population resource imbalance, human behavioral ecology, and agency theories. Resource imbalance theory predicts appearance of density dependent adaptive problems prior to major cultural transformations. Human behavioral ecology predicts increased dietary diversity and incorporation of greater processing costs occuring coincidentally with reduced residential mobility. Symbolic mate value advertising is a predicted leadership strategy. Agency theory predicts internal sources of social tension, potentially independent of external forces, as primary causes of cultural change. Feast hosting and the formation political economy are expected to be central to both social processes investigated from this perspective. Local paleoclimatic proxies suggest aridity from ca 4000--2000 B.C.E. Reanalysis of pedestrian survey data indicate population growth during the Late Archaic. Excavation and ground penetrating radar survey at Pirco and Jiskairumoko demonstrate reduced residential mobility and increased evidence for social differentiation appearing during the Late Archaic's (before 3000 B.C.E.) end. New cultural patterns include: pithouses, more groundstone, internal storage, costly non-local artifacts, domesticated plants and animals, costly grave goods, and use of ochre in symbolic contexts. No clear cut evidence for inter-community promotional feasting was identified but some finds suggest intra-community alliance feasts. By the end of the Terminal Archaic ca. 1500 B

Tools for Closure Project and Contract Management: Development of the Rocky Flats Integrated Closure Project Baseline

International Nuclear Information System (INIS)

Gelles, C. M.; Sheppard, F. R.

2002-01-01

This paper details the development of the Rocky Flats Integrated Closure Project Baseline - an innovative project management effort undertaken to ensure proactive management of the Rocky Flats Closure Contract in support of the Department's goal for achieving the safe closure of the Rocky Flats Environmental Technology Site (RFETS) in December 2006. The accelerated closure of RFETS is one of the most prominent projects within the Department of Energy (DOE) Environmental Management program. As the first major former weapons plant to be remediated and closed, it is a first-of-kind effort requiring the resolution of multiple complex technical and institutional challenges. Most significantly, the closure of RFETS is dependent upon the shipment of all special nuclear material and wastes to other DOE sites. The Department is actively working to strengthen project management across programs, and there is increasing external interest in this progress. The development of the Rocky Flats Integrated Closure Project Baseline represents a groundbreaking and cooperative effort to formalize the management of such a complex project across multiple sites and organizations. It is original in both scope and process, however it provides a useful precedent for the other ongoing project management efforts within the Environmental Management program

SITE Technology Capsule. Demonstration of Rocky Mountain Remediation Services Soil Amendment

Science.gov (United States)

This report briefly summarizes the Rocky Mountain Remediation Services treatment technology demonstration of a soil amendment process for lead contaminated soil at Roseville, OH. The evaluation included leaching, bioavailability, geotechnical, and geochemical methods.

Microwave solidification development for Rocky Flats waste

Energy Technology Data Exchange (ETDEWEB)

Dixon, D.; Erle, R.; Eschen, V. [and others

1994-04-01

The Microwave Engineering Team at the Rocky Flats Plant has developed a production-scale system for the treatment of hazardous, radioactive, and mixed wastes using microwave energy. The system produces a vitreous final form which meets the acceptance criteria for shipment and disposal. The technology also has potential for application on various other waste streams from the public and private sectors. Technology transfer opportunities are being identified and pursued for commercialization of the microwave solidification technology.

Microwave solidification development for Rocky Flats waste

International Nuclear Information System (INIS)

Dixon, D.; Erle, R.; Eschen, V.

1994-04-01

The Microwave Engineering Team at the Rocky Flats Plant has developed a production-scale system for the treatment of hazardous, radioactive, and mixed wastes using microwave energy. The system produces a vitreous final form which meets the acceptance criteria for shipment and disposal. The technology also has potential for application on various other waste streams from the public and private sectors. Technology transfer opportunities are being identified and pursued for commercialization of the microwave solidification technology

Rocky Mountain Research Station invasive species visionary white paper

Science.gov (United States)

D. E. Pearson; M. Kim; J. Butler

2011-01-01

Invasive species represent one of the single greatest threats to natural ecosystems and the services they provide. Effectively addressing the invasive species problem requires management that is based on sound research. We provide an overview of recent and ongoing invasive species research conducted by Rocky Mountain Research Station scientists in the Intermountain...

13 CFR 142.38 - Can the administrative complaint be settled voluntarily?

Science.gov (United States)

2010-01-01

... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Can the administrative complaint be settled voluntarily? 142.38 Section 142.38 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION PROGRAM FRAUD CIVIL REMEDIES ACT REGULATIONS Decisions and Appeals § 142.38 Can the administrative...

Implementing DOE guidance for hazards assessments at Rocky Flats Plant

International Nuclear Information System (INIS)

Zimmerman, G.A.

1993-01-01

Hazards Assessments are performed for a variety of activities and facilities at Rocky Flats Plant. Prior to 1991, there was no guidance for performing Hazards Assessments. Each organization that performed Hazards Assessments used its own methodology with no attempt at standardization. In 1991, DOE published guidelines for the performance of Hazards Assessments for Emergency Planning (DOE-EPG-5500.1, ''Guidance for a Hazards Assessment Methodology''). Subsequently, in 1992, DOE published a standard for the performance of Hazards Assessments (DOE-STD-1027-92, ''Hazard Categorization and Accident Analysis, Techniques for Compliance with DOE Order 5480.23, Nuclear Safety Analysis Reports''). Although these documents are a step in the direction of standardization, there remains a great deal of interpretation and subjective implementation in the performance of Hazards Assessments. Rocky Flats Plant has initiated efforts to develop a uniform and standard process to be used for Hazards Assessments

Actinide solution processing at the Rocky Flats Environmental Technology Site

International Nuclear Information System (INIS)

1995-04-01

The Department of Energy (DOE) has prepared an Environmental Assessment (EA), DOE/EA-1039, for radioactive solution removal and processing at Rocky Flats Environmental Technology Site, Golden, Colorado. The proposal for solution removal and processing is in response to independent safety assessments and an agreement with the State of Colorado to remove mixed residues at Rocky Flats and reduce the risk of future accidents. Monthly public meetings were held during the scoping and preparation of the EA. The scope of the EA included evaluations of alternative methods and locations of solution processing. A comment period from February 20, 1995 through March 21, 1995 was provided to the public and the State of Colorado to offer written comment on the EA. Comments were received from the State of Colorado and the U.S. Environmental Protection Agency. A response to the agency comments is included in the Final EA

Significance of settling model structures and parameter subsets in modelling WWTPs under wet-weather flow and filamentous bulking conditions.

Science.gov (United States)

Ramin, Elham; Sin, Gürkan; Mikkelsen, Peter Steen; Plósz, Benedek Gy

2014-10-15

Current research focuses on predicting and mitigating the impacts of high hydraulic loadings on centralized wastewater treatment plants (WWTPs) under wet-weather conditions. The maximum permissible inflow to WWTPs depends not only on the settleability of activated sludge in secondary settling tanks (SSTs) but also on the hydraulic behaviour of SSTs. The present study investigates the impacts of ideal and non-ideal flow (dry and wet weather) and settling (good settling and bulking) boundary conditions on the sensitivity of WWTP model outputs to uncertainties intrinsic to the one-dimensional (1-D) SST model structures and parameters. We identify the critical sources of uncertainty in WWTP models through global sensitivity analysis (GSA) using the Benchmark simulation model No. 1 in combination with first- and second-order 1-D SST models. The results obtained illustrate that the contribution of settling parameters to the total variance of the key WWTP process outputs significantly depends on the influent flow and settling conditions. The magnitude of the impact is found to vary, depending on which type of 1-D SST model is used. Therefore, we identify and recommend potential parameter subsets for WWTP model calibration, and propose optimal choice of 1-D SST models under different flow and settling boundary conditions. Additionally, the hydraulic parameters in the second-order SST model are found significant under dynamic wet-weather flow conditions. These results highlight the importance of developing a more mechanistic based flow-dependent hydraulic sub-model in second-order 1-D SST models in the future. Copyright © 2014 Elsevier Ltd. All rights reserved.

Fire, fuels, and restoration of ponderosa pine-Douglas-fir forests in the Rocky Mountains, USA

OpenAIRE

Baker, W. L.; Veblen, T. T.; Sherriff, R. L.

2007-01-01

Forest restoration in ponderosa pine and mixed ponderosa pine–Douglas fir forests in the US Rocky Mountains has been highly influenced by a historical model of frequent, low-severity surface fires developed for the ponderosa pine forests of the Southwestern USA. A restoration model, based on this low-severity fire model, focuses on thinning and prescribed burning to restore historical forest structure. However, in the US Rocky Mountains, research on fire history and forest structure, and earl...

Structure of macroalgal communities on tropical rocky shores inside and outside a marine protected area.

Science.gov (United States)

Portugal, Adriana Brizon; Carvalho, Fabrício Lopes; Soares, Marcelo de Oliveira; Horta, Paulo Antunes; de Castro Nunes, José Marcos

2017-09-01

The structure of marine macroalgal communities and morpho-functional groups were investigated in a poorly characterized region on the Tropical Southwestern Atlantic coast, Brazil. The survey was conducted at six rocky shores located on the mainland and on coastal islands distributed inside a marine protected area (MPA) and outside the MPA (near a densely populated area). We hypothesized that tropical rocky shores inside the MPA and islands have higher species richness, diversity, and evenness of marine macroalgae. Results confirmed that species richness, diversity and evenness were significantly higher inside the MPA than in rocky shores outside the MPA. Only species richness was higher on islands than on the mainland. The results suggest that human impacts could lead to a competitive advantage and dominance in the articulated calcareous morphotype, resulting in community differences and lower benthic biodiversity in tropical ecosystems near urbanized sites. Copyright © 2017 Elsevier Ltd. All rights reserved.

Wave actions and topography determine the small-scale spatial distribution of newly settled Asari clams Ruditapes philippinarum on a tidal flat

Science.gov (United States)

Nambu, Ryogen; Saito, Hajime; Tanaka, Yoshio; Higano, Junya; Kuwahara, Hisami

2012-03-01

There are many studies on spatial distributions of Asari clam Ruditapes philippinarum adults on tidal flats but few have dealt with spatial distributions of newly settled Asari clam (physical/topographical conditions on tidal flats. We examined small-scale spatial distributions of newly settled individuals on the Matsunase tidal flat, central Japan, during the low spring tides on two days 29th-30th June 2007, together with the shear stress from waves and currents on the flat. The characteristics of spatial distribution of newly settled Asari clam markedly varied depending on both of hydrodynamic and topographical conditions on the tidal flat. Using generalized linear models (GLMs), factors responsible for affecting newly settled Asari clam density and its spatial distribution were distinguished between sampling days, with "crest" sites always having a negative influence each on the density and the distribution on both sampling days. The continuously recorded data for the wave-current flows at the "crest" site on the tidal flat showed that newly settled Asari clam, as well as bottom sediment particles, at the "crest" site to be easily displaced. Small-scale spatial distributions of newly settled Asari clam changed with more advanced benthic stages in relation to the wave shear stress.

NPDES Permit for Rocky Mountain Arsenal Recycled Water Pipeline in Colorado

Science.gov (United States)

Under NPDES permit CO-0035009, the U.S. Department of Interior's Fish and Wildlife Service is authorized to discharge from the Rocky Mountain Arsenal recycled water pipeline to Lower Derby Lake in Adams County, Colo.

Aquatic Resources of Rocky Mountain Arsenal Adams County, Colorado

Science.gov (United States)

1989-09-01

Consequently, temperatures rise and oxygen levels fall. Primary producers in these stretches shift from periphyton to phytoplankton (suspended algae ...trees and have rocky substrates. Primary production in these cold- water and coolwater reaches is generally limited to periphyton (attached algae ...Adams County. Biotic components investigated included phytoplankton , zooplankton, aquatic macrophytes, benthic macroinvertebrates, fish eggs and

A numerical investigation of fine sediment resuspension in the wave boundary layer - effect of hindered settling and bedforms

Science.gov (United States)

Hsu, T. J.; Cheng, Z.; Yu, X.

2016-02-01

The wave bottom boundary layer is a major conduit delivering fine terrestrial sediments to the continental margin. Hence, studying the fine sediment resuspension in the wave boundary layer is crucial to the understanding of various components of the earth system, such as carbon cycle. By assuming the settling velocity to be a constant in each simulation, previous turbulence-resolving numerical simulations reveal the existence of three transport modes in the wave boundary layer associated with the sediment availability. As the sediment availability and hence the sediment-induced stable stratification increase, a sequence of transport modes, namely, (I) well-mixed transport, (II) formulation of lutocline resembling a two-layer system, and (III) completely laminarized transport are observed. In general, the settling velocity is a flow variable due to the floc dynamics and hindered settling. This study further investigate the effect of hindered settling. Particularly, for flocs with lower gelling concentrations, the hindered settling effect can play a key role in sustaining large amount of suspended sediment load and results in the laminarized transport (III). For the simulation with a very significant hindered settling effect due to a low gelling concentration, results also indicate the occurrence of gelling ignition, a state in which the erosion rate is always higher than the deposition rate. A condition for the occurrence of gelling ignition is proposed for a range of wave intensities as a function of sediment/floc properties and erodibility parameters. These aforementioned studies are limited to fine sediment transport over a flat bed. However, recent field and laboratory observation show that a small amount of sand fraction can lead to the formation of small bedforms, which can armor the bed while in the meantime enhance near bed turbulence. Preliminary investigation on the effect of bedforms on the resulting transport modes will also be presented.

Tank 4 Characterization, Settling, And Washing Studies

International Nuclear Information System (INIS)

Bannochie, C.; Pareizs, J.; Click, D.; Zamecnik, J.

2009-01-01

A sample of PUREX sludge from Tank 4 was characterized, and subsequently combined with a Tank 51 sample (Tank 51-E1) received following Al dissolution, but prior to a supernate decant by the Tank Farm, to perform a settling and washing study to support Sludge Batch 6 preparation. The sludge source for the majority of the Tank 51-E1 sample is Tank 12 HM sludge. The Tank 51-E1 sample was decanted by SRNL prior to use in the settling and washing study. The Tank 4 sample was analyzed for chemical composition including noble metals. The characterization of the Tank 51-E1 sample, used here in combination with the Tank 4 sample, was reported previously. SRNL analyses on Tank 4 were requested by Liquid Waste Engineering (LWE) via Technical Task Request (TTR) HLE-TTR-2009-103. The sample preparation work is governed by Task Technical and Quality Assurance Plan (TTQAP), and analyses were controlled by an Analytical Study Plan and modifications received via customer communications. Additional scope included a request for a settling study of decanted Tank 51-E1 and a blend of decanted Tank 51-E1 and Tank 4, as well as a washing study to look into the fate of undissolved sulfur observed during the Tank 4 characterization. The chemistry of the Tank 4 sample was modeled with OLI Systems, Inc. StreamAnalyzer to determine the likelihood that sulfate could exist in this sample as insoluble Burkeite (2Na 2 SO 4 · Na 2 CO 3 ). The OLI model was also used to predict the composition of the blended tank materials for the washing study. The following conclusions were drawn from the Tank 4 analytical results reported here: (1) Any projected blend of Tank 4 and the current Tank 51 contents will produce a SB6 composition that is lower in Ca and U than the current SB5 composition being processed by DWPF. (2) Unwashed Tank 4 has a relatively large initial S concentration of 3.68 wt% on a total solids basis, and approximately 10% of the total S is present as an insoluble or undissolved form

45 CFR 681.42 - Can the administrative complaint be settled voluntarily?

Science.gov (United States)

2010-10-01

... 45 Public Welfare 3 2010-10-01 2010-10-01 false Can the administrative complaint be settled voluntarily? 681.42 Section 681.42 Public Welfare Regulations Relating to Public Welfare (Continued) NATIONAL SCIENCE FOUNDATION PROGRAM FRAUD CIVIL REMEDIES ACT REGULATIONS Decisions and Appeals § 681.42 Can the...

Quality of groundwater in the Denver Basin aquifer system, Colorado, 2003-5

Science.gov (United States)

Musgrove, MaryLynn; Beck, Jennifer A.; Paschke, Suzanne; Bauch, Nancy J.; Mashburn, Shana L.

2014-01-01

Groundwater resources from alluvial and bedrock aquifers of the Denver Basin are critical for municipal, domestic, and agricultural uses in Colorado along the eastern front of the Rocky Mountains. Rapid and widespread urban development, primarily along the western boundary of the Denver Basin, has approximately doubled the population since about 1970, and much of the population depends on groundwater for water supply. As part of the National Water-Quality Assessment Program, the U.S. Geological Survey conducted groundwater-quality studies during 2003–5 in the Denver Basin aquifer system to characterize water quality of shallow groundwater at the water table and of the bedrock aquifers, which are important drinking-water resources. For the Denver Basin, water-quality constituents of concern for human health or because they might otherwise limit use of water include total dissolved solids, fluoride, sulfate, nitrate, iron, manganese, selenium, radon, uranium, arsenic, pesticides, and volatile organic compounds. For the water-table studies, two monitoring-well networks were installed and sampled beneath agricultural (31 wells) and urban (29 wells) land uses at or just below the water table in either alluvial material or near-surface bedrock. For the bedrock-aquifer studies, domestic- and municipal-supply wells completed in the bedrock aquifers were sampled. The bedrock aquifers, stratigraphically from youngest (shallowest) to oldest (deepest), are the Dawson, Denver, Arapahoe, and Laramie-Fox Hills aquifers. The extensive dataset collected from wells completed in the bedrock aquifers (79 samples) provides the opportunity to evaluate factors and processes affecting water quality and to establish a baseline that can be used to characterize future changes in groundwater quality. Groundwater samples were analyzed for inorganic, organic, isotopic, and age-dating constituents and tracers. This report discusses spatial and statistical distributions of chemical constituents

Validation of KENO-based criticality calculations at Rocky Flats

International Nuclear Information System (INIS)

Felsher, P.D.; McKamy, J.N.; Monahan, S.P.

1992-01-01

In the absence of experimental data, it is necessary to rely on computer-based computational methods in evaluating the criticality condition of a nuclear system. The validity of the computer codes is established in a two-part procedure as outlined in ANSI/ANS 8.1. The first step, usually the responsibility of the code developer, involves verification that the algorithmic structure of the code is performing the intended mathematical operations correctly. The second step involves an assessment of the code's ability to realistically portray the governing physical processes in question. This is accomplished by determining the code's bias, or systematic error, through a comparison of computational results to accepted values obtained experimentally. In this paper, the authors discuss the validation process for KENO and the Hansen-Roach cross sections in use at EG and G Rocky Flats. The validation process at Rocky Flats consists of both global and local techniques. The global validation resulted in a maximum k eff limit of 0.95 for the limiting-accident scanarios of a criticality evaluation

Settling of fixed erythrocyte suspension droplets

Science.gov (United States)

Omenyi, S. N.; Snyder, R. S.

1983-01-01

It is pointed out that when particles behave collectively rather than individually, the fractionation of micron-size particles on the basis of size, density, and surface characteristics by centrifugation and electrophoresis is hindered. The formation and sedimentation of droplets containing particles represent an extreme example of collective behavior and pose a major problem for these separation methods when large quantities of particles need to be fractionated. Experiments are described that measure droplet sizes and settling rates for a variety of particles and droplets. Expressions relating the particle concentration in a drop to measurable quantities of the fluids and particles are developed. The number of particles in each droplet is then estimated, together with the effective droplet density. Red blood cells from different animals fixed in glutaraldehyde provide model particle groups.

Colloidal stability of suspended and agglomerate structures of settled carbon nanotubes in different aqueous matrices.

Science.gov (United States)

Schwyzer, Irène; Kaegi, Ralf; Sigg, Laura; Nowack, Bernd

2013-08-01

Carbon nanotubes (CNTs) are often processed in suspended form and therefore a release of CNT-suspensions into the aquatic environment is plausible. In this study, the behaviour of two physico-chemically very different CNT types in the presence of varying, environmentally relevant calcium-containing media was investigated, including the long-term colloidal stability and the sedimentary structures of settled CNTs. Calcium induced CNT flocculation, however, the stability of the CNTs in the medium did not monotonously decrease with increasing calcium concentration. At intermediate calcium concentrations (0.5-1.5 mM Ca) pre-dispersed CNTs were stabilized in humic acid medium to similar, temporarily even to higher degree than in the absence of calcium. Between pH 5 and 8 only at the highest pH an influence on CNT stability was observed by either promoting flocculation or stabilisation depending on the CNT type. Humic acid stabilized CNTs much better than fulvic acid. Generally, the colloidal stability of the long, thick CNTs with higher surface oxygen content was less affected by the media composition. An investigation of the settled CNT material using analytical electron microscopy revealed the presence of spheroidal, bundle-like and net like CNT-agglomerate structures. Calcium possibly acted as bridging agent linking CNTs in a network like manner, temporarily increasing the CNT concentrations stabilized in the supernatants due to the low density of these structures. With increasing settling time the CNTs formed a fluffy sediment layer at the bottom of the reaction vessels. Bundle-like CNT agglomerates were also observed within that layer of settled CNTs, possibly caused by calcium neutralizing the surface charges. Furthermore, the CNT suspensions contained spheroidal CNT agglomerates, most likely residues from the original dry powder that were not disaggregated. The analysis of settled CNT material is a novelty and illustrates CNT agglomerate structures possibly

Long-term effects of the water-accomodated fraction (WAF) of diesel oil on rocky shore populations maintained in experimental mesocosms

Energy Technology Data Exchange (ETDEWEB)

Bokn, T.L. [Norwegian Inst. for Water Research, Oslo (Norway); Moy, F.E. [Norwegian Inst. for Water Research, Oslo (Norway); Murray, S.N. [California State Univ., Fullerton, CA (United States). Dept. of Biological Science

1993-12-31

The long-term effects of continuous doses (average hydrocarbon concentration =129.4 {mu}g L{sup -1} and 30.1 {mu}g L{sup -1}) of the water-accommodated fraction (WAF) of diesel oil on 15 rocky littoral populations were determined at three tidal levels in experimental mesocosms over two years. At each tidal level, most species exhibited similar abundance changes in both oil-contaminated and control (average background hydrocarbon concentration = 5.6 {mu}g L{sup -1}) mesocosms. Significant changes in species abundances attributable to oil (WAF) were demonstrated for only two of ten seaweeds and three of five invertebrates. Compared with the other mesocosms, significantly greater reductions in upper-level cover were recorded in the basin receiving the highest oil dosage for the seaweeds Phymatolithon lenormandii and Fucus evanescents together with lower recruitment of the barnacle Semibalanus balanoides. The mussel Mytilus edulis was storngly affected by the oil treatments and essentially disappeared from both oil-contaminated mesocosms. Numbers of the starfish Asterias rubens also fell to zero at the lowest tidal level in the basin receiving the highest oil dosage. There were no demonstrable differences in the abundance patterns of the gastropod Littorina littorea, the crab Carcinus maenus, and a total of eight brown (Ascophyllum nodosum, Fucus serratus, F. vesiculosus, Laminaria digitata), red (Chondrus crispus), and green (Cladophora rupestris, Enteromorpha spp., Ulva lactuca) seaweeds in the oil-contaminated compared with the control mesocosms. (orig.)

Long-term effects of the water-accomodated fraction (WAF) of diesel oil on rocky shore populations maintained in experimental mesocosms

International Nuclear Information System (INIS)

Bokn, T.L.; Moy, F.E.; Murray, S.N.

1993-01-01

The long-term effects of continuous doses (average hydrocarbon concentration =129.4 μg L -1 and 30.1 μg L -1 ) of the water-accommodated fraction (WAF) of diesel oil on 15 rocky littoral populations were determined at three tidal levels in experimental mesocosms over two years. At each tidal level, most species exhibited similar abundance changes in both oil-contaminated and control (average background hydrocarbon concentration = 5.6 μg L -1 ) mesocosms. Significant changes in species abundances attributable to oil (WAF) were demonstrated for only two of ten seaweeds and three of five invertebrates. Compared with the other mesocosms, significantly greater reductions in upper-level cover were recorded in the basin receiving the highest oil dosage for the seaweeds Phymatolithon lenormandii and Fucus evanescents together with lower recruitment of the barnacle Semibalanus balanoides. The mussel Mytilus edulis was storngly affected by the oil treatments and essentially disappeared from both oil-contaminated mesocosms. Numbers of the starfish Asterias rubens also fell to zero at the lowest tidal level in the basin receiving the highest oil dosage. There were no demonstrable differences in the abundance patterns of the gastropod Littorina littorea, the crab Carcinus maenus, and a total of eight brown (Ascophyllum nodosum, Fucus serratus, F. vesiculosus, Laminaria digitata), red (Chondrus crispus), and green (Cladophora rupestris, Enteromorpha spp., Ulva lactuca) seaweeds in the oil-contaminated compared with the control mesocosms. (orig.)

Factors controlling the field settling velocity of cohesive sediment in estuaries

DEFF Research Database (Denmark)

Pejrup, Morten; Mikkelsen, Ole

2010-01-01

in the correlation of the description of W-50 and the controlling parameters from each area can be obtained. A generic algorithm describing the data from all the investigated areas is suggested. It works well within specific tidal areas but fails to give a generic description of the field settling velocity....

Environment, safety and Health Progress Assessment of the Rocky Flats Plant

International Nuclear Information System (INIS)

1993-05-01

This report documents the result of the US Department of Energy's (DOE) Environment, Safety and Health (ES ampersand H) Progress Assessment of the DOE Rocky Flats Plant (RFP) in Golden, Colorado. The assessment, which was conducted during the period of May 17 through May 28, 1993, included a selective review of the ES ampersand H management systems and programs of the responsible DOE Headquarters Program Offices (Defense Programs (DP) and Environmental Restoration and Waste Management (EM)), the DOE Rocky Flats Office (RFO), and the site contractor, EG ampersand G Rocky Flats, Inc. (EG ampersand G). Despite the near constant state of flux under which RFP has been required to operate, the Progress Assessment Team has concluded that significant progress has been made in correcting the deficiencies identified in the 1989 Assessment and in responding responsibly to regulations, and DOE directives and guidance that have been issued since that time. The Team concluded that the improvements have been concentrated in the activities associated with plutonium facilities and in regulatory driven programs. Much remains to be done with respect to implementing on a sitewide basis those management systems that anchor an organization's pursuit of continuous ES ampersand H improvement. Furthermore the Team concluded that the pace of improvement has been constrained by a combination of factors that have limited the site's ability to manage change in the pursuit of sitewide ES ampersand H excellence

Heavy metal concentration of settled surface dust in residential building

International Nuclear Information System (INIS)

Nor Aimi abdul Wahab; Fairus Muhamad Darus; Norain Isa; Siti Mariam Sumari; Nur Fatihah Muhamad Hanafi

2012-01-01

The concentrations of heavy metals (Cu, Ni, Pb and Zn) in settled surface dust were collected from nine residential buildings in different areas in Seberang Prai Tengah District, Pulau Pinang. The samples of settled surface dust were collected in 1 m 2 area by using a polyethylene brush and placed in the dust pan by sweeping the living room floor most accessible to the occupants. Heavy metals concentrations were determined by using inductively coupled plasma optical emission spectrometer (ICP-OES) after digestion with nitric acid and sulphuric acid. The results show that the range of heavy metals observed in residential buildings at Seberang Prai Tengah were in the range of 2.20-14.00 mg/ kg, 1.50-32.70 mg/ kg, 1.50-76.80 mg/ kg and 14.60-54.40 mg/ kg for Cu, Ni, Pb and Zn respectively. The heavy metal concentration in the investigated areas followed the order: Pb > Zn > Ni > Cu. Statistical analysis indicates significant correlation between all the possible pairs of heavy metal. The results suggest a likely common source for the heavy metal contamination, which could be traced most probably to vehicular emissions, street dust and other related activities. (author)

Analysis of suspended solids transport processes in primary settling tanks.

Science.gov (United States)

Patziger, Miklós; Kiss, Katalin

2015-01-01

The paper shows the results of a long-term research comprising FLUENT-based numerical modeling, in situ measurements and laboratory tests to analyze suspended solids (SS) transport processes in primary settling tanks (PSTs). The investigated PST was one of the rectangular horizontal flow PSTs at a large municipal wastewater treatment plant (WWTP) of a capacity of 500,000 population equivalent. Many middle-sized and large WWTPs are equipped with such PSTs. The numerical PST model was calibrated and validated based on the results of comprehensive in situ flow and SS concentration measurements from low (5 m/h) up to quite high surface overflow rates of 9.5 and 13.0 m/h and on settling and other laboratory tests. The calibrated and validated PST model was also successfully used for evaluation of some slight modifications of the inlet geometry (removing lamellas, installing a flocculation 'box', shifting the inlet into a 'bottom-near' or into a 'high' position), which largely affect PST behavior and performance. The investigations provided detailed insight into the flow and SS transport processes within the investigated PST, which strongly contributes to hydrodynamically driven design and upgrading of PSTs.

[Relationships between soil and rocky desertification in typical karst mountain area based on redundancy analysis].

Science.gov (United States)

Long, Jian; Liao, Hong-Kai; Li, Juan; Chen, Cai-Yun

2012-06-01

Redundancy analysis (RDA) was employed to reveal the relationships between soil and rocky desertification through vegetation investigation and analysis of soil samples collected in typical karst mountain area of southwest Guizhou Province. The results showed that except TP, TK and ACa, all other variables including SOC, TN, MBC, ROC, DOC, available nutrients and basal respiration showed significant downward trends during the rocky desertification process. RDA results showed significant correlations between different types of desertification and soil variables, described as non-degraded > potential desertification > light desertification > moderate desertification > severe desertification. Moreover, RDA showed that using SOC, TN, AN, and BD as soil indicators, 74.4% of the variance information on soil and rocky desertification could be explained. Furthermore, the results of correlation analysis showed that soil variables were significantly affected by surface vegetation. Considering the ecological function of the aboveground vegetation and the soil quality, Zanthoxylum would be a good choice for restoration of local vegetation in karst mountain area.

Translating science into policy: Using ecosystem thresholds to protect resources in Rocky Mountain National Park

International Nuclear Information System (INIS)

Porter, Ellen; Johnson, Susan

2007-01-01

Concern over impacts of atmospheric nitrogen deposition to ecosystems in Rocky Mountain National Park, Colorado, has prompted the National Park Service, the State of Colorado Department of Public Health and Environment, the Environmental Protection Agency, and interested stakeholders to collaborate in the Rocky Mountain National Park Initiative, a process to address these impacts. The development of a nitrogen critical load for park aquatic resources has provided the basis for a deposition goal to achieve resource protection, and parties to the Initiative are now discussing strategies to meet that goal by reducing air pollutant emissions that contribute to nitrogen deposition in the Park. Issues being considered include the types and locations of emissions to be reduced, the timeline for emission reductions, and the impact of emission reductions from programs already in place. These strategies may serve as templates for addressing ecosystem impacts from deposition in other national parks. - A collaborative approach between scientists and policymakers is described for addressing nitrogen deposition effects to Rocky Mountain National Park, USA

Effect of Ionic Strength on Settling of Activated Sludge

OpenAIRE

M Ahmadi Moghadam, M Soheili, MM Esfahani

2005-01-01

Structural properties of activated sludge flocs were found to be sensitive to small changes in ionic strength. This study investigates the effect of ionic strength on settling of activated sludge. Samples were taken from activated sludge process of Ghazvin Sasan soft drink wastewater treatment plant, then treated with different ionic strengths of KCl and CaCl2 solution, after that the turbidity of supernatant was measured. The results indicated that low ionic strength resulted in a steeper sl...

Directions for improving the design of horizontal settling tanks

Energy Technology Data Exchange (ETDEWEB)

Basev, V A; Vaseva, V N

1979-01-01

Basic trends are presented for improving the design of horizontal settling tanks in recent years in order to increase hydraulic load on them and their efficient operation. An analysis is made of the suggested different designs of feed and uptake water-distributors, systems of concentrated recovery of clarified water and fine-layer elements. The most advanced of them was selected. The latter was recommended for practical use or experimental verification during purification of mine waters from suspended substances.

Restoring rocky intertidal communities: Lessons from a benthic macroalgal ecosystem engineer.

Science.gov (United States)

Bellgrove, Alecia; McKenzie, Prudence F; Cameron, Hayley; Pocklington, Jacqueline B

2017-04-15

As coastal population growth increases globally, effective waste management practices are required to protect biodiversity. Water authorities are under increasing pressure to reduce the impact of sewage effluent discharged into the coastal environment and restore disturbed ecosystems. We review the role of benthic macroalgae as ecosystem engineers and focus particularly on the temperate Australasian fucoid Hormosira banksii as a case study for rocky intertidal restoration efforts. Research focussing on the roles of ecosystem engineers is lagging behind restoration research of ecosystem engineers. As such, management decisions are being made without a sound understanding of the ecology of ecosystem engineers. For successful restoration of rocky intertidal shores it is important that we assess the thresholds of engineering traits (discussed herein) and the environmental conditions under which they are important. Copyright © 2017 Elsevier Ltd. All rights reserved.

Carmen Miranda’s white dress: ethnicity, syncretism and subaltern sexualities in springtime in the rockies Carmen Miranda’s white dress: ethnicity, syncretism and subaltern sexualities in springtime in the rockies

Directory of Open Access Journals (Sweden)

José Gatti

2008-04-01

Full Text Available This essay calls for a reassessment of Carmen Miranda's work in Hollywood. Her singing and dancing can reveal unexpected ethnic and cultural alignments. The focus here is on the costumes she designed for Springtime in the Rockies, a Fox musical in which Brazilian as well as Native American cultural references are made explicit in Miranda's performance. This essay calls for a reassessment of Carmen Miranda's work in Hollywood. Her singing and dancing can reveal unexpected ethnic and cultural alignments. The focus here is on the costumes she designed for Springtime in the Rockies, a Fox musical in which Brazilian as well as Native American cultural references are made explicit in Miranda's performance.

A test of the ADV-based Reynolds flux method for in situ estimation of sediment settling velocity in a muddy estuary

Science.gov (United States)

Cartwright, Grace M.; Friedrichs, Carl T.; Smith, S. Jarrell

2013-12-01

Under conditions common in muddy coastal and estuarine environments, acoustic Doppler velocimeters (ADVs) can serve to estimate sediment settling velocity ( w s) by assuming a balance between upward turbulent Reynolds flux and downward gravitational settling. Advantages of this method include simple instrument deployment, lack of flow disturbance, and relative insensitivity to biofouling and water column stratification. Although this method is being used with increasing frequency in coastal and estuarine environments, to date it has received little direct ground truthing. This study compared in situ estimates of w s inferred by a 5-MHz ADV to independent in situ observations from a high-definition video settling column over the course of a flood tide in the bottom boundary layer of the York River estuary, Virginia, USA. The ADV-based measurements were found to agree with those of the settling column when the current speed at about 40 cm above the bed was greater than about 20 cm/s. This corresponded to periods when the estimated magnitude of the settling term in the suspended sediment continuity equation was four or more times larger than the time rate of change of concentration. For ADV observations restricted to these conditions, ADV-based estimates of w s (mean 0.48±0.04 mm/s) were highly consistent with those observed by the settling column (mean 0.45±0.02 mm/s). However, the ADV-based method for estimating w s was sensitive to the prescribed concentration of the non-settling washload, C wash. In an objective operational definition, C wash can be set equal to the lowest suspended solids concentration observed around slack water.

Magnetotelluric Imaging of Lower Crustal Melt and Lithospheric Hydration in the Rocky Mountain Front Transition Zone, Colorado, USA

Science.gov (United States)

Feucht, D. W.; Sheehan, A. F.; Bedrosian, P. A.

2017-12-01

We present an electrical resistivity model of the crust and upper mantle from two-dimensional (2-D) anisotropic inversion of magnetotelluric data collected along a 450 km transect of the Rio Grande rift, southern Rocky Mountains, and High Plains in Colorado, USA. Our model provides a window into the modern-day lithosphere beneath the Rocky Mountain Front to depths in excess of 150 km. Two key features of the 2-D resistivity model are (1) a broad zone ( 200 km wide) of enhanced electrical conductivity (minerals, with maximum hydration occurring beneath the Rocky Mountain Front. This lithospheric "hydration front" has implications for the tectonic evolution of the continental interior and the mechanisms by which water infiltrates the lithosphere.

Trichothecene mycotoxins and their determinants in settled dust related to grain production.

Science.gov (United States)

Nordby, Karl-Christian; Halstensen, Anne Straumfors; Elen, Oleif; Clasen, Per-Erik; Langseth, Wenche; Kristensen, Petter; Eduard, Wijnand

2004-01-01

We hypothesise that inhalant exposure to mycotoxins causes developmental outcomes and certain hormone-related cancers that are associated with grain farming in an epidemiological study. The aim of the present study was to identify and validate determinants of measured trichothecene mycotoxins in grain dust as work environmental trichothecene exposure indicators. Settled grain dust was collected in 92 Norwegian farms during seasons of 1999 and 2000. Production characteristics and climatic data were studied as determinants of trichothecenes in settled dust samples obtained during the production of barley (N = 59), oats (N = 32), and spring wheat (N = 13). Median concentrations of trichothecenes in grain dust were grain dust in this study. Differences in cereal species, production properties and districts contributed less to explain mycotoxin concentrations. Fungal forecasts are validated as indicators of mycotoxin exposure of grain farmers and their use in epidemiological studies may be warranted.

A fatal urban case of rocky mountain spotted fever presenting an eschar in San Jose, Costa Rica.

Science.gov (United States)

Argüello, Ana Patricia; Hun, Laya; Rivera, Patricia; Taylor, Lizeth

2012-08-01

This study reports the first urban human case of Rocky Mountain spotted fever caused by Rickettsia rickettsii, in Costa Rica. An 8-year-old female who died at the National Children's Hospital 4 days after her admission, and an important and significant observation was the presence of an "eschar" (tache noire), which is typical in some rickettsial infections but not frequent in Rocky Mountain spotted fever cases.

Case report: Co-infection of Rickettsia rickettsii and Streptococcus pyogenes: is fatal Rocky Mountain spotted fever underdiagnosed?

Science.gov (United States)

Raczniak, Gregory A; Kato, Cecilia; Chung, Ida H; Austin, Amy; McQuiston, Jennifer H; Weis, Erica; Levy, Craig; Carvalho, Maria da Gloria S; Mitchell, Audrey; Bjork, Adam; Regan, Joanna J

2014-12-01

Rocky Mountain spotted fever, a tick-borne disease caused by Rickettsia rickettsii, is challenging to diagnose and rapidly fatal if not treated. We describe a decedent who was co-infected with group A β-hemolytic streptococcus and R. rickettsii. Fatal cases of Rocky Mountain spotted fever may be underreported because they present as difficult to diagnose co-infections. © The American Society of Tropical Medicine and Hygiene.

Characterizing the effects of cell settling on bioprinter output

International Nuclear Information System (INIS)

Pepper, Matthew E; Burg, Timothy C; Burg, Karen J L; Groff, Richard E; Seshadri, Vidya

2012-01-01

The time variation in bioprinter output, i.e. the number of cells per printed drop, was studied over the length of a typical printing experiment. This variation impacts the cell population size of bioprinted samples, which should ideally be consistent. The variation in output was specifically studied in the context of cell settling. The bioprinter studied is based on the thermal inkjet HP26A cartridge; however, the results are relevant to other cell delivery systems that draw fluid from a reservoir. A simple mathematical model suggests that the cell concentration in the bottom of the reservoir should increase linearly over time, up to some maximum, and that the cell output should be proportional to this concentration. Two studies were performed in which D1 murine stem cells and similarly sized polystyrene latex beads were printed. The bead output profiles were consistent with the model. The cell output profiles initially followed the increasing trend predicted by the settling model, but after several minutes the cell output peaked and then decreased. The decrease in cell output was found to be associated with the number of use cycles the cartridge had experienced. The differing results for beads and cells suggest that a biological process, such as adhesion, causes the decrease in cell output. Further work will be required to identify the exact process. (communication)

Reseeding of mussels on denuded rocky shores: preliminary studies ...

African Journals Online (AJOL)

A method is developed to establish clumps of mussels Perna perna in denuded areas on high-energy rocky shores on the south-east coast of South Africa. A total of 20 small (20–30 mm total length) mussels is placed under a 30 cm half-section of perforated PVC drainage pipe bolted to the rock surface. The pipe is left in ...

Some aspects of organic and inorganic particulate transport at Rocky Flats. Final report

International Nuclear Information System (INIS)

Nichols, H.

Findings from the summer 1975 sampling program and the conclusions from the 1975-1976 winter sampling program are summarized. Large radionuclide particles were not found attached to pollen. Sampling the airborne pollen throughout the Rocky Flats area demonstrated that the Rocky Flats air samplers were deficient in their abilities to properly collect large lightweight pollen grains. This may not have serious consequences for the undetected transport of radionuclides by pollen, however, it has implications of sampling inefficiency in some particulate size ranges, and implies that if radionuclides are carried at times by larger particles, then the standard Rocky Flats air samplers are not sampling these materials efficiently. Some initial findings suggested that soil samples from downwind areas associated with winter snow accumulation had abnormally high fissile particle accumulations, and this suggested the need to sample these sites in winter. Areas of preferred particle accumulation such as snow banks had higher concentrations of radionuclide particles than surrounding areas which are more windswept. Any soil sampling program at Rocky Flats which seeks to monitor background radionuclide levels and movement of fissile particles across the site should take account of these topographically and wind-controlled accumulation areas, and not rely solely on a grid pattern of sampling. The snow samples contained radionuclide material in substantial quantities. In terms of fissile particulates smaller than 0.5 microns the snow banks three miles east of the plant site contained as much or more radionuclides than sites close to the Hot Spot contaminated area. The snow samples immediately east of the Hot Spot contained many more large particles (>0.5 m), as did soil samples from the upwind site next to the plant fence. The Hot Spot is clearly implicated again as the source of these materials

Coal fly ash basins as an attractive nuisance to birds: parental provisioning exposes nestlings to harmful trace elements.

Science.gov (United States)

Bryan, A L; Hopkins, W A; Parikh, J H; Jackson, B P; Unrine, J M

2012-02-01

Birds attracted to nest around coal ash settling basins may expose their young to contaminants by provisioning them with contaminated food. Diet and tissues of Common Grackle (Quiscalus quiscala) nestlings were analyzed for trace elements to determine if nestlings were accumulating elements via dietary exposure and if feather growth limits elemental accumulation in other tissues. Arsenic, cadmium, and selenium concentrations in ash basin diets were 5× higher than reference diets. Arsenic, cadmium, and selenium concentrations were elevated in feather, liver, and carcass, but only liver Se concentrations approached levels of concern. Approximately 15% of the total body burden of Se, As, and Cd was sequestered in feathers of older (>5 days) nestlings, whereas only 1% of the total body burden of Sr was sequestered in feathers. Feather concentrations of only three elements (As, Se, and Sr) were correlated with liver concentrations, indicating their value as non-lethal indicators of exposure. Copyright © 2011 Elsevier Ltd. All rights reserved.

Litigation Technical Support and Services, Rocky Mountain Arsenal

Science.gov (United States)

1989-05-01

34 d V) W C > - d) 4- -~ 0 - - .4 ..- di L *..L 3~1 3-~ v mi a- a t - --- w- Vdi 4 - ý 0 -4 0 m~ -j m0 m’ .- us 0 Ill i to -v .4 I 4 1 t A ~ 3Ul t -4...2060. Marlow, D. J. 1979g, November 8. Pest control report, October 1979. Rocky Mountain Arsenal. Microfilm RMA182, Franes 2048 -2053 Marlow, D. J

Progress towards a lightning ignition model for the Northern Rockies

Science.gov (United States)

Paul Sopko; Don Latham

2010-01-01

We are in the process of constructing a lightning ignition model specific to the Northern Rockies using fire occurrence, lightning strike, ecoregion, and historical weather, NFDRS (National Fire Danger Rating System), lightning efficiency and lightning "possibility" data. Daily grids for each of these categories were reconstructed for the 2003 fire season (...

Sintopy of two Tropidurus lizard species (Squamata: Tropiduridae) in a rocky Cerrado habitat in Central Brazil

OpenAIRE

Faria,R. G.; Araujo,A. F. B.

2004-01-01

We studied the ecology of Tropidurus itambere and T. oreadicus that occur syntopically in rocky habitats of Cerrado vegetation in central Brazil during the dry season (April to September 2000). The two species are ecologically similar, but somewhat differentiated in vertical microhabitat use. The two species preferred rocky surface microhabitat. Both species demonstrated a unimodal activity pattern, with a peak between 10 and 15 h. Their diets were similar in composition and prey size. The mo...

STP K Basin Sludge Sample Archive at the Pacific Northwest National Laboratory FY2014

Energy Technology Data Exchange (ETDEWEB)

Fiskum, Sandra K.; Smoot, Margaret R.; Schmidt, Andrew J.

2014-06-01

The Pacific Northwest National Laboratory (PNNL) currently houses 88 samples (~10.5 kg) of K Basin sludge (81 wet and seven dry samples) on behalf of the Sludge Treatment Project (STP), which is managed for the U.S. Department of Energy (DOE) by the CH2M Hill Plateau Remediation Company (CHPRC). Selected samples are intended to serve, in part, as sentinels to enhance understanding of sludge properties after long-term storage, and thus enhance understanding of sludge behavior following transfer to sludge transfer and storage containers (STSCs) and storage at the Hanford 200 Area central plateau. In addition, remaining samples serve in contingency for future testing requirements. At PNNL, the samples are tracked and maintained under a prescriptive and disciplined monthly sample-monitoring program implemented by PNNL staff. This report updates the status of the K Basin archive sludge sample inventory to April 2014. The previous inventory status report, PNNL 22245 (Fiskum et al. 2013, limited distribution report), was issued in February of 2013. This update incorporates changes in the inventory related to repackaging of 17 samples under test instructions 52578 TI052, K Basin Sludge Sample Repackaging for Continued Long Term Storage, and 52578 TI053, K Basin Sludge Sample Repackaging Post-2014 Shear Strength Measurements. Note that shear strength measurement results acquired in 2014 are provided separately. Specifically, this report provides the following: • a description of the K Basin sludge sample archive program and the sample inventory • a summary and images of the samples that were repackaged in April 2014 • up-to-date images and plots of the settled density and water loss from all applicable samples in the inventory • updated sample pedigree charts, which provide a roadmap of the genesis and processing history of each sample in the inventory • occurrence and deficiency reports associated with sample storage and repackaging

Climate along the crest of the US Rocky Mountains during the last glaciation: preliminary insights from numerical modeling of paleoglaciers

Science.gov (United States)

Leonard, E. M.; Laabs, B. J.; Plummer, M. A.; Huss, E.; Spiess, V. M.; Mackall, B. T.; Jacobsen, R. E.; Quirk, B.

2012-12-01

Climate conditions at the time of the local Last Glacial Maximum (LGM) in the US Rocky Mountains were assessed using a 2-d coupled glacier energy/mass-balance and ice-flow model (Plummer and Phillips, 2003). The model was employed to understand the conditions that would be necessary to sustain valley glaciers and small mountain icecaps at their maximum extents in eight areas distributed along the crest of the range from northern New Mexico (35.8oN) to northern Montana (48.6oN). For each setting, model experiments yield a set of temperature and precipitation combinations that may have accompanied the local LGM. If the results of global and regional climate models are used to constrain temperature depression estimates from our model experiments, the following precipitation pattern emerges for the local LGM. In the northern Rocky Mountains in Montana and northern Wyoming, model results suggest a strong reduction in precipitation of 50% or more. In the central Rocky Mountains of southern Wyoming and Colorado, precipitation appears to have been 50-90% of modern. By contrast, precipitation appears to have been strongly enhanced in the southern Rocky Mountains of New Mexico. These results are broadly consistent with a pattern of precipitation observed in global and regional climate simulations of the LGM in the western U.S., in which precipitation was reduced in the northern Rocky Mountains but increased in the southern Rocky Mountains. This pattern may reflect a southward displacement of mean position the Pacific Jet Stream in western North America during and possibly following the LGM.

Hydrologic properties and ground-water flow systems of the Paleozoic rocks in the upper Colorado River basin in Arizona, Colorado, New Mexico, Utah, and Wyoming, excluding the San Juan Basin

Science.gov (United States)

Geldon, Arthur L.

2003-01-01

The hydrologic properties and ground-water flow systems of Paleozoic sedimentary rocks in the Upper Colorado River Basin were investigated under the Regional Aquifer-System Analysis (RASA) program of the U.S. Geological Survey in anticipation of the development of water supplies from bedrock aquifers to fulfill the region's growing water demands. The study area, in parts of Arizona, Colorado, New Mexico, Utah, and Wyoming, covers about 100,000 square miles. It includes parts of four physiographic provinces--the Middle Rocky Mountains, Wyoming Basin, Southern Rocky Mountains, and Colorado Plateaus. A variety of landforms, including mountains, plateaus, mesas, cuestas, plains, badlands, and canyons, are present. Altitudes range from 3,100 to 14,500 feet. Precipitation is distributed orographically and ranges from less than 6 inches per year at lower altitudes to more than 60 inches per year in some mountainous areas. Most of the infrequent precipitation at altitudes of less than 6,000 feet is consumed by evapotranspiration. The Colorado and Green Rivers are the principal streams: the 1964-82 average discharge of the Colorado River where it leaves the Upper Colorado River Basin is 12,170 cubic feet per second (a decrease of 5,680 cubic feet per second since construction of Glen Canyon Dam in 1963). On the basis of their predominant lithologic and hydrologic properties, the Paleozoic rocks are classified into four aquifers and three confining units. The Flathead aquifer, Gros Ventre confining unit, Bighorn aquifer, Elbert-Parting confining unit, and Madison aquifer (Redwall-Leadville and Darwin-Humbug zones) make up the Four Corners aquifer system. A thick sequence, composed mostly of Mississippian and Pennsylvanian shale, anhydrite, halite, and carbonate rocks--the Four Corners confining unit (Belden-Molas and Paradox-Eagle Valley subunits)--overlies the Four Corners aquifer system in most areas and inhibits vertical ground-water flow between the Four Corners aquifer

Regeneration of Rocky Mountain bristlecone pine (Pinus aristata) and limber pine (Pinus flexilis) three decades after stand-replacing fires

Science.gov (United States)

Jonathan D. Coop; Anna W. Schoettle

2009-01-01

Rocky Mountain bristlecone pine (Pinus aristata) and limber pine (Pinus flexilis) are important highelevation pines of the southern Rockies that are forecast to decline due to the recent spread of white pine blister rust (Cronartium ribicola) into this region. Proactive management strategies to promote the evolution of rust resistance and maintain ecosystem function...

Outbreak of Rocky Mountain spotted fever in Córdoba, Colombia.

Science.gov (United States)

Hidalgo, Marylin; Miranda, Jorge; Heredia, Damaris; Zambrano, Pilar; Vesga, Juan Fernando; Lizarazo, Diana; Mattar, Salim; Valbuena, Gustavo

2011-02-01

Rocky Mountain spotted fever (RMSF) is a tick-borne disease caused by the obligate intracellular bacterium Rickettsia rickettsii. Although RMSF was first reported in Colombia in 1937, it remains a neglected disease. Herein, we describe the investigation of a large cluster of cases of spotted fever rickettsiosis in a new area of Colombia.

Rocky Mountain Research Station 2008-2012 National Fire Plan Investments

Science.gov (United States)

Erika Gallegos

2013-01-01

This report highlights selected accomplishments by the USDA Forest Service Rocky Mountain Research Station's Wildland Fire and Fuels Research & Development projects in support of the National Fire Plan from 2008 through 2012. These projects are examples of the broad range of knowledge and tools developed by National Fire Plan funding beginning in 2008.

Integrating understanding of biophysical processes governing larval fish dispersal with basin-scale management decisions: lessons from the Missouri River, USA

Science.gov (United States)

Erwin, S. O.; Jacobson, R. B.; Fischenich, C. J.; Bulliner, E. A., IV; McDonald, R.; DeLonay, A. J.; Braaten, P.; Elliott, C. M.; Chojnacki, K.

2017-12-01

Management of the Missouri River—the longest river in the USA, with a drainage basin covering one sixth of the conterminous USA—is increasingly driven by the need to understand biophysical processes governing the dispersal of 8-mm long larval pallid sturgeon. In both the upper and lower basin, survival of larval sturgeon is thought to be a bottleneck limiting populations, but because of different physical processes at play, different modeling frameworks and resolutions are required to link management actions with population-level responses. In the upper basin, a series of impoundments reduce the length of river for the drifting larval sturgeon to complete their development. Downstream from the mainstem dams, recruitment is most likely diminished by channelization and reduced floodplain connectivity that limit the benthic habitat available for larval sturgeon to settle and initiate feeding. We present a synthesis of complementary field studies, laboratory observations, and numerical simulations that evaluate the physical processes related to larval dispersal of sturgeon in the Missouri River basin. In the upper basin, we use one-dimensional advection-dispersion models, calibrated with field experiments conducted in 2016-2017 using surrogate particles and tracers, to evaluate reservoir management alternatives. Results of field experimentation and numerical modeling show that proposed management alternatives in the upper basin may be limited by insufficient lengths of flowing river for drifting larvae to fully develop into their juvenile lifestage. In the intensively engineered lower basin, we employ higher resolution measurements and models to evaluate potential for channel reconfiguration and flow alteration to promote successful interception of drifting larvae into supportive benthic habitats for the initiation of feeding and transition to the juvenile life stage. We illustrate how refined understanding of small-scale biophysical process has been incorporated

TEMPERATURE STRUCTURE AND ATMOSPHERIC CIRCULATION OF DRY TIDALLY LOCKED ROCKY EXOPLANETS

Energy Technology Data Exchange (ETDEWEB)

Koll, Daniel D. B.; Abbot, Dorian S., E-mail: dkoll@uchicago.edu [Department of the Geophysical Sciences, University of Chicago, Chicago, IL 60637 (United States)

2016-07-10

Next-generation space telescopes will observe the atmospheres of rocky planets orbiting nearby M-dwarfs. Understanding these observations will require well-developed theory in addition to numerical simulations. Here we present theoretical models for the temperature structure and atmospheric circulation of dry, tidally locked rocky exoplanets with gray radiative transfer and test them using a general circulation model (GCM). First, we develop a radiative-convective (RC) model that captures surface temperatures of slowly rotating and cool atmospheres. Second, we show that the atmospheric circulation acts as a global heat engine, which places strong constraints on large-scale wind speeds. Third, we develop an RC-subsiding model which extends our RC model to hot and thin atmospheres. We find that rocky planets develop large day–night temperature gradients at a ratio of wave-to-radiative timescales up to two orders of magnitude smaller than the value suggested by work on hot Jupiters. The small ratio is due to the heat engine inefficiency and asymmetry between updrafts and subsidence in convecting atmospheres. Fourth, we show, using GCM simulations, that rotation only has a strong effect on temperature structure if the atmosphere is hot or thin. Our models let us map out atmospheric scenarios for planets such as GJ 1132b, and show how thermal phase curves could constrain them. Measuring phase curves of short-period planets will require similar amounts of time on the James Webb Space Telescope as detecting molecules via transit spectroscopy, so future observations should pursue both techniques.

The Department of Energy's Rocky Flats Plant: A guide to record series useful for health-related research. Volume 5: Waste management

International Nuclear Information System (INIS)

1995-01-01

This is the fifth in a series of seven volumes which constitute a guide to records of the Rocky Flats Plant useful for conducting health-related research. The primary purpose of Volume 5 is to describe record series pertaining to waste management activities at the Department of Energy's (DOE) Rocky Flats Plant, now named the Rocky Flats Environmental Technology Site, near Denver, Colorado. History Associates Incorporated (HAI) prepared this guide as part of its work as the support services contractor for DOE's Epidemiologic Records Inventory Project. This introduction briefly describes the Epidemiologic Records Inventory Project and HAI's role in the project, provides a history of waste management practices at Rocky Flats, and identifies organizations contributing to waste management policies and activities. Other topics include the scope and arrangement of this volume and the organization to contact for access to these records

Climate control on Quaternary coal fires and landscape evolution, Powder River basin, Wyoming and Montana

Energy Technology Data Exchange (ETDEWEB)

Riihimaki, C.A.; Reiners, P.W.; Heffern, E.L. [Drew University, Madison, NJ (USA). Dept. of Biology

2009-03-15

Late Cenozoic stream incision and basin excavation have strongly influenced the modern Rocky Mountain landscape, but constraints on the timing and rates of erosion are limited. The geology of the Powder River basin provides an unusually good opportunity to address spatial and temporal patterns of stream incision. Numerous coal seams in the Paleocene Fort Union and Eocene Wasatch Formations within the basin have burned during late Cenozoic incision, as coal was exposed to dry and oxygen-rich near-surface conditions. The topography of this region is dominated by hills capped with clinker, sedimentary rocks metamorphosed by burning of underlying coal beds. We use (U-Th)/He ages of clinker to determine times of relatively rapid erosion, with the assumption that coal must be near Earth's surface to burn. Ages of 55 in situ samples range from 0.007 to 1.1 Ma. Clinker preferentially formed during times in which eccentricity of the Earth's orbit was high, times that typically but not always correlate with interglacial periods. Our data therefore suggest that rates of landscape evolution in this region are affected by climate fluctuations. Because the clinker ages correlate better with eccentricity time series than with an oxygen isotope record of global ice volume, we hypothesize that variations in solar insolation modulated by eccentricity have a larger impact on rates of landscape evolution in this region than do glacial-interglacial cycles.

[Impact of Rocky Desertification Treatment on Underground Water Chemistry and Dissolved Inorganic Carbon Isotope in Karst Areas].

Science.gov (United States)

Xiao, Shi-zhen; Xiong, Kang-ning; Lan, Jia-cheng; Zhang, Hui; Yang, Long

2015-05-01

Five springs representing different land-use types and different karst rocky desertification treatment models were chosen at the Huajiang Karst Rocky Desertification Treatment Demonstration Site in Guanling-Zhenfeng Counties in Guizhou, to analyze the features of underground water chemistry and dissolved inorganic carbon isotopes (δ13C(DIC)) and reveal the effect of rocky desertification treatment on karstification and water quality. It was found that, the underground water type of the research area was HCO3-Ca; the water quality of the springs which were relatively less affected by human activities including Shuijingwan Spring (SJW) , Gebei Spring (GB), and Maojiawan Spring (MJW) was better than those relatively more affected by human activities including Diaojing Spring (DJ) and Tanjiazhai Spring (TJZ) , the main ion concentrations and electrical conductivity of which were higher; pH, SIc and pCO2 were sensitive to land-use types and rocky desertification treatment, which could be shown by the higher pH and SIc and lower pCO2 in MJW than those in the other four springs; (Ca(2+) + Mg2+)/HCO(3-) of SJW, MJW and GB were nearly 1:1, dominated by carbonate rock weathering by carbon acid, while the (Ca(2+) + Mg2+) of DJ and TJZ was much higher than HCO3-, suggesting that sulfate and nitrate might also dissolve carbonate rock because of the agricultural activities; δ13C(DIC) was lighter in wet season because of the higher biological activities; the average δ13C(DIC) was in the order of DJ (-12.79 per thousand) desertification and lighter after the rocky desertification are treated and controlled.

Crystal accumulation in the Hanford Waste Treatment Plant high level waste melter. Preliminary settling and resuspension testing

Energy Technology Data Exchange (ETDEWEB)

Fox, K. M. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Fowley, M. D. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Miller, D. H. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

2016-05-01

The full-scale, room-temperature Hanford Tank Waste Treatment and Immobilization Plant (WTP) High-Level Waste (HLW) melter riser test system was successfully operated with silicone oil and magnetite particles at a loading of 0.1 vol %. Design and construction of the system and instrumentation, and the selection and preparation of simulant materials, are briefly reviewed. Three experiments were completed. A prototypic pour rate was maintained, based on the volumetric flow rate. Settling and accumulation of magnetite particles were observed at the bottom of the riser and along the bottom of the throat after each experiment. The height of the accumulated layer at the bottom of the riser, after the first pouring experiment, approximated the expected level given the solids loading of 0.1 vol %. More detailed observations of particle resuspension and settling were made during and after the third pouring experiment. The accumulated layer of particles at the bottom of the riser appeared to be unaffected after a pouring cycle of approximately 15 minutes at the prototypic flow rate. The accumulated layer of particles along the bottom of the throat was somewhat reduced after the same pouring cycle. Review of the time-lapse recording showed that some of the settling particles flow from the riser into the throat. This may result in a thicker than expected settled layer in the throat.

History of Uranium-233(233U)Processing at the Rocky Flats Plant. In support of the RFETS Acceptable Knowledge Program

International Nuclear Information System (INIS)

Moment, R.L.; Gibbs, F.E.; Freiboth, C.J.

1999-01-01

This report documents the processing of Uranium-233 at the Rocky Flats Plant (Rocky Flats Environmental Technology Site). The information may be used to meet Waste Isolation Pilot Plant (WIPP) Waste Acceptance Criteria (WAC)and for determining potential Uranium-233 content in applicable residue waste streams

Book Review :The Essential Guide to Rocky Mountain Mushrooms by Habitat

Science.gov (United States)

A mushroom guide book, 'The Essential Guide to Rocky Mountain Mushrooms by Habitat' by Cathy L. Cripps, Vera S. Evenson, and Michael Kou (University of Illinois Press, 260 pages), is reviewed in non-technical fashion from the standpoints of format, comprehensiveness, and clarity. Postive features (...

Rocky Worlds Limited to ∼1.8 Earth Radii by Atmospheric Escape during a Star’s Extreme UV Saturation

Energy Technology Data Exchange (ETDEWEB)

Lehmer, Owen R.; Catling, David C., E-mail: info@lehmer.us [Dept. Earth and Space Sciences, Box 351310, University of Washington, Seattle, WA (United States)

2017-08-20

Recent observations and analysis of low-mass (<10 M {sub ⊕}) exoplanets have found that rocky planets only have radii up to 1.5–2 R {sub ⊕}. Two general hypotheses exist for the cause of the dichotomy between rocky and gas-enveloped planets (or possible water worlds): either low-mass planets do not necessarily form thick atmospheres of a few wt.%, or the thick atmospheres on these planets easily escape, driven by X-ray and extreme ultraviolet (XUV) emissions from young parent stars. Here, we show that a cutoff between rocky and gas-enveloped planets due to hydrodynamic escape is most likely to occur at a mean radius of 1.76 ± 0.38 (2 σ ) R {sub ⊕} around Sun-like stars. We examine the limit in rocky planet radii predicted by hydrodynamic escape across a wide range of possible model inputs, using 10,000 parameter combinations drawn randomly from plausible parameter ranges. We find a cutoff between rocky and gas-enveloped planets that agrees with the observed cutoff. The large cross-section available for XUV absorption in the extremely distended primitive atmospheres of low-mass planets results in complete loss of atmospheres during the ∼100 Myr phase of stellar XUV saturation. In contrast, more-massive planets have less-distended atmospheres and less escape, and so retain thick atmospheres through XUV saturation—and then indefinitely as the XUV and escape fluxes drop over time. The agreement between our model and exoplanet data leads us to conclude that hydrodynamic escape plausibly explains the observed upper limit on rocky planet size and few planets (a “valley”, or “radius gap”) in the 1.5–2 R {sub ⊕} range.

Rocky Flats Plant Site Environmental Report: 1993 Highlights

International Nuclear Information System (INIS)

1993-01-01

The Rocky Flats Plant Site Environmental Report provides summary information on the plant's environmental monitoring programs and the results recorded during 1993. The report contains a compliance summary, results of environmental monitoring and other related programs, a review of environmental remediation activities, information on external gamma radiation dose monitoring, and radiation dose estimates for the surrounding population. This section provides an overview of these topics and summarizes more comprehensive discussions found in the main text of this annual report

Comparative wood anatomy of some shrubs native to the Northern Rocky Mountains

Science.gov (United States)

Arlene Dale

1968-01-01

This paper describes some xylem characteristics of the more important shrub species of the Northern Rockies and presents a key for identifying shrub-wood specimens by microscopic characters. The paper contains photomicrographs of 55 shrub woods.

Influence of sludge properties and hydraulic loading on the performance of secondary settling tanks--full-scale operational results.

Science.gov (United States)

Vestner, R J; Günthert, F Wolfgang

2004-01-01

Full-scale investigations at a WWTP with a two-stage secondary settling tank process revealed relationships between significant operating parameters and performance in terms of effluent suspended solids concentration. Besides common parameters (e.g. surface overflow rate and sludge volume loading rate) feed SS concentration and flocculation time must be considered. Concentration of the return activated sludge may help to estimate the performance of existing secondary settling tanks.

Isotopic composition of rainfall and runoff in a small arid basin with implications for deep percolation

International Nuclear Information System (INIS)

Dody, A.

1995-08-01

The aim of this work was to characterize the isotopic composition of potential recharge in an arid rocky watershed. Unique field observations were obtained from an arid watershed in the Negev Highlands, Israel, through utilization of the dynamic variations in the isotopic composition of rainfall and runoff. The hydrological system's inputs are rainfall and its isotopic composition. Rainfall and runoff were sampled in eight storms. High variability in the isotopic composition of rainfall was observed during any single rainstorm. The isotopic distribution in the runoff at the outlet of the basin appeared often not to be correlated to the isotopic patterns of the associated rain storm. A new mathematical model was developed to describe these physical processes. The model called A Double-Component Kinematic Wave Flow and Transport Approach, was designated to assess the dynamic isotopic distribution in arid rain storms and runoff. This model simulates the transport of rainfall into overland flow and runoff in an arid rocky watershed with uniformly distributed shallow depression storage. A numerical solution for the problem was developed, to estimate the depression storage parameters. The model also reflects the isotopic memory effect due to the depression storage between sequential rain showers. A good agreement between the observed and computed hydrograph and the change of the δ 18O values in runoff in time confirms the validity of the model. (author) 138 figs., 125 refs

Cascading effects of ocean acidification in a rocky subtidal community.

Directory of Open Access Journals (Sweden)

Valentina Asnaghi

Full Text Available Temperate marine rocky habitats may be alternatively characterized by well vegetated macroalgal assemblages or barren grounds, as a consequence of direct and indirect human impacts (e.g. overfishing and grazing pressure by herbivorous organisms. In future scenarios of ocean acidification, calcifying organisms are expected to be less competitive: among these two key elements of the rocky subtidal food web, coralline algae and sea urchins. In order to highlight how the effects of increased pCO2 on individual calcifying species will be exacerbated by interactions with other trophic levels, we performed an experiment simultaneously testing ocean acidification effects on primary producers (calcifying and non-calcifying algae and their grazers (sea urchins. Artificial communities, composed by juveniles of the sea urchin Paracentrotus lividus and calcifying (Corallina elongata and non-calcifying (Cystoseira amentacea var stricta, Dictyota dichotoma macroalgae, were subjected to pCO2 levels of 390, 550, 750 and 1000 µatm in the laboratory. Our study highlighted a direct pCO2 effect on coralline algae and on sea urchin defense from predation (test robustness. There was no direct effect on the non-calcifying macroalgae. More interestingly, we highlighted diet-mediated effects on test robustness and on the Aristotle's lantern size. In a future scenario of ocean acidification a decrease of sea urchins' density is expected, due to lower defense from predation, as a direct consequence of pH decrease, and to a reduced availability of calcifying macroalgae, important component of urchins' diet. The effects of ocean acidification may therefore be contrasting on well vegetated macroalgal assemblages and barren grounds: in the absence of other human impacts, a decrease of biodiversity can be predicted in vegetated macroalgal assemblages, whereas a lower density of sea urchin could help the recovery of shallow subtidal rocky areas affected by overfishing from

Cascading effects of ocean acidification in a rocky subtidal community.

Science.gov (United States)

Asnaghi, Valentina; Chiantore, Mariachiara; Mangialajo, Luisa; Gazeau, Frédéric; Francour, Patrice; Alliouane, Samir; Gattuso, Jean-Pierre

2013-01-01

Temperate marine rocky habitats may be alternatively characterized by well vegetated macroalgal assemblages or barren grounds, as a consequence of direct and indirect human impacts (e.g. overfishing) and grazing pressure by herbivorous organisms. In future scenarios of ocean acidification, calcifying organisms are expected to be less competitive: among these two key elements of the rocky subtidal food web, coralline algae and sea urchins. In order to highlight how the effects of increased pCO2 on individual calcifying species will be exacerbated by interactions with other trophic levels, we performed an experiment simultaneously testing ocean acidification effects on primary producers (calcifying and non-calcifying algae) and their grazers (sea urchins). Artificial communities, composed by juveniles of the sea urchin Paracentrotus lividus and calcifying (Corallina elongata) and non-calcifying (Cystoseira amentacea var stricta, Dictyota dichotoma) macroalgae, were subjected to pCO2 levels of 390, 550, 750 and 1000 µatm in the laboratory. Our study highlighted a direct pCO2 effect on coralline algae and on sea urchin defense from predation (test robustness). There was no direct effect on the non-calcifying macroalgae. More interestingly, we highlighted diet-mediated effects on test robustness and on the Aristotle's lantern size. In a future scenario of ocean acidification a decrease of sea urchins' density is expected, due to lower defense from predation, as a direct consequence of pH decrease, and to a reduced availability of calcifying macroalgae, important component of urchins' diet. The effects of ocean acidification may therefore be contrasting on well vegetated macroalgal assemblages and barren grounds: in the absence of other human impacts, a decrease of biodiversity can be predicted in vegetated macroalgal assemblages, whereas a lower density of sea urchin could help the recovery of shallow subtidal rocky areas affected by overfishing from barren grounds to

Field guide to diseases & insects of the Rocky Mountain Region

Science.gov (United States)

Forest Health Protection. Rocky Mountain Region

2010-01-01

This field guide is a forest management tool for field identification of biotic and abiotic agents that damage native trees in Colorado, Kansas, Nebraska, South Dakota, and Wyoming, which constitute the USDA Forest Service's Rocky Mountain Region. The guide focuses only on tree diseases and forest insects that have significant economic, ecological, and/ or...

Floc Size and Settling Velocity Observations From Three Contrastingly Different Natural Environments in the USA

Science.gov (United States)

Manning, Andrew; Schoellhamer, David; Mehta, Ashish; Nover, Daniel; Schladow, Geoffrey

2010-05-01

Environmentally, monitoring the movement of suspended cohesive sediments is highly desirable in both estuaries and lakes. When modelling cohesive sediment transport and mass settling fluxes, the settling speed of the suspended matter is a key parameter. In contrast to purely non-cohesive sandy sediments, mud can flocculate and this poses a serious complication to the modelling of sediment pathways. As flocs grow in size they become more porous and significantly less dense, but their settling speeds continue to rise due to a Stokes' Law relationship. Much research has been conducted on the flocculation characteristics of suspended muddy sediments in saline/brackish tidal conditions, where electrostatic particle bonding can occur. However very little is known about freshwater floc dynamics. This is primarily due to flocs being extremely delicate entities and are thus very difficult to observe in situ. This paper primarily describes a recently developed, portable, low intrusive instrument INSSEV_LF, which permits the direct, in situ measurement of both floc size (D) and settling velocity (Ws), simultaneously. Examples of floc spectra observed from three different environments within the USA are presented and compared. The first site was the turbidity maximum zone in San Francisco Bay, where the suspended solids concentration (SSC) was 170 mg.l-1 and many low density macroflocs up to 400 μm in diameter, settling at speeds of 4-8 mm.s-1 were observed. The second location was the shallow (1.7 m mean depth), freshwater environment of Lake Apopka in Florida. It is highly eutrophic, and demonstrates a turbid SSC of 750 mg.l-1 within a benthic suspension layer. These conditions resulted in D from 45 μm up to 1,875 μm; 80% of the floc were > 160 μm (i.e. macroflocs). Present theories for the settling of flocs rely on fractal theory of self-similarity, but this does not appear to be applicable to the Lake Apopka flocs because they do not possess any basic geometric unit

Studi Numerik Karakterisasi Aliran 3 Dimensi Multifase (Gas-Solid) Pada Gravity Settling Chamber Dengan Variasi Kecepatan Inlet Dan Diameter Partikel Pada Aliran Dilute Phase

OpenAIRE

Isa’i, Adi Mochammad; Widodo, Wawan Aries

2013-01-01

Kegiatan pemilahan pada aktivitas produksi merupakan salah satu kegiatan yang banyak dilakukan pada dunia industri. Penggunaan gravity settling chamber merupakan teknologi pemilahan partikel yang paling sedehana dan murah. Maka dalam perancangan suatu gravity settling chamber perlu diketahui parameter yang mempengaruhi kinerja dari alat tersebut. Analisa karakteristik aliran pada gravity settling chamber dilakukan dengan metode simulasi numerik menggunakan persamaan Eularian-Lagrangian. Sebu...

Studi Numerik Karakterisasi Aliran 3 Dimensi Multifase (Gas-Solid) Pada Gravity Settling Chamber Dengan Variasi Kecepatan Inlet Dan Diameter Partikel Pada Aliran Dilute Phase

OpenAIRE

Adi Mochammad Isa’i; Wawan Aries Widodo

2013-01-01

Kegiatan  pemilahan pada aktivitas produksi merupakan salah satu kegiatan yang banyak dilakukan pada dunia industri. Penggunaan gravity settling chamber merupakan teknologi pemilahan partikel yang paling sedehana dan murah. Maka dalam perancangan suatu gravity settling chamber perlu diketahui parameter yang mempengaruhi kinerja dari alat tersebut. Analisa karakteristik aliran pada gravity settling chamber dilakukan dengan metode simulasi numerik menggunakan persamaan Eularian-Lagrangian. Sebu...

Application of radionuclides in water management. I. Sedimentation of industrial and municipal waste waters in settling basing

Energy Technology Data Exchange (ETDEWEB)

Blaha, L; Thyn, J [Ustav pro Vyzkum, Vyrobu a Vyuziti Radioisotopu, Prague (Czechoslovakia); Spilowski, S; Strzelczak, G [Institute of Nuclear Research, Warsaw (Poland)

1978-04-01

Methods are described of measurement and processing of the pulse response of liquids obtained inside and on the outlet of industrial settling tanks of the DORRA type. The results are used for determining the hydrodynamic characteristics, for estimating the internal recycle and the efficient volume of the tank and for determining the mean flow rates between measuring points. The /sup 82/Br nuclide was used for the determination of the pulse response. A radiotracer (/sup 198/Au) was used for labelling suspended solid particles in determining sedimentation curves in a vertical glass tube. The sedimentation curves and the pulse response of the device were used for the evaluation of the settling process. On the basis of these measurements, the variation of the critical depth of sedimentation and the effective volume of the settling tank were determined as a function of the suspension flow rate in the device (2 to 10 m/sup 3/min/sup -1/).

Understanding and Managing the Effects of Climate Change on Ecosystem Services in the Rocky Mountains

Directory of Open Access Journals (Sweden)

Jessica E. Halofsky

2017-08-01

Full Text Available Public lands in the US Rocky Mountains provide critical ecosystem services, especially to rural communities that rely on these lands for fuel, food, water, and recreation. Climate change will likely affect the ability of these lands to provide ecosystem services. We describe 2 efforts to assess climate change vulnerabilities and develop adaptation options on federal lands in the Rocky Mountains. We specifically focus on aspects that affect community economic security and livelihood security, including water quality and quantity, timber, livestock grazing, and recreation. Headwaters of the Rocky Mountains serve as the primary source of water for large populations, and these headwaters are located primarily on public land. Thus, federal agencies will play a key role in helping to protect water quantity and quality by promoting watershed function and water conservation. Although increased temperatures and atmospheric concentration of CO2 have the potential to increase timber and forage production in the Rocky Mountains, those gains may be offset by wildfires, droughts, insect outbreaks, non-native species, and altered species composition. Our assessment identified ways in which federal land managers can help sustain forest and range productivity, primarily by increasing ecosystem resilience and minimizing current stressors, such as invasive species. Climate change will likely increase recreation participation. However, recreation managers will need more flexibility to adjust practices, provide recreation opportunities, and sustain economic benefits to communities. Federal agencies are now transitioning from the planning phase of climate change adaptation to implementation to ensure that ecosystem services will continue to be provided from federal lands in a changing climate.

Evaluation of episodic acidification and amphibian declines in the Rocky Mountains

Science.gov (United States)

Frank A. Vertucci; Paul Stephen Corn

1996-01-01

We define criteria for documenting episodic acidification of amphibian breeding habitats and examine whether episodic acidification is responsible for observed declines of amphibian populations in the Rocky Mountains. Anthropogenic episodic acidification, caused by atmospheric deposition of sulfate and nitrate, occurs when the concentration of acid anions increases...

Dust Allergens within Rural Northern Rocky Mountain Residences.

Science.gov (United States)

Weiler, Emily; Semmens, Erin; Noonan, Curtis; Cady, Carol; Ward, Tony

2015-01-23

To date, few studies have characterized allergens within residences located in rural areas of the northern Rocky Mountain region. In this study, we collected dust samples from 57 homes located throughout western Montana and northern Idaho. Dust samples were collected and later analyzed for dust mite allergens Der f 1 and Der p 1 , Group 2 mite allergens ( Der p 2 and Der f 2 ), domestic feline ( Fel d 1 ), and canine ( Can f 1 ). Indoor temperature and humidity levels were also measured during the sampling program, as were basic characteristics of each home. Dog (96%) and cat (82%) allergens were the most prevalent allergens found in these homes (even when a feline or canine did not reside in the home). Results also revealed the presence of dust mites. Seven percent (7%) of homes tested positive for Der p 1 , 19% of homes were positive for Der f 1 , and 5% of homes were positive for the Group 2 mite allergens. Indoor relative humidity averaged 27.0 ± 7.6% within the homes. Overall, humidity was not significantly associated with dust mite presence, nor was any of the other measured home characteristics. This study provides a descriptive assessment of indoor allergen presence (including dust mites) in rural areas of the northern Rocky Mountains, and provides new information to assist regional patients with reducing allergen exposure using in-home intervention strategies.

Circumscribing campo rupestre - megadiverse Brazilian rocky montane savanas.

Science.gov (United States)

Alves, R J V; Silva, N G; Oliveira, J A; Medeiros, D

2014-05-01

Currently campo rupestre (CR) is a name accepted and used internationally by botanists, zoologists, and other naturalists, usually applied to a very specific ecosystem, despite the lack of a consensual published circumscription. We present a tentative geographic circumscription of the term, combining data on climate, geology, geomorphology, soil, flora, fauna and vegetation. The circumscription of campo rupestre proposed herein is based on the following premises: (1) the classification of vegetation is not an exact science, and it is difficult to attain a high degree of consensus to the circumscription of vegetation names; (2) despite this, vegetation classification is useful for conservation and management. It is thus desirable to circumscribe vegetation types with the greatest attainable precision; (3) there is a need to preserve all montane and rocky vegetation types, regardless of classification, biome, etc; (4) the CRs are formed by a complex mosaic of vegetation types including rock-dwelling, psammophilous, aquatic, epiphytic, and penumbral plant communities. Campos rupestres stricto sensu are a Neotropical, azonal vegetation complex endemic to Brazil, forming a mosaic of rocky mountaintop "archipelagos" inserted within a matrix of zonal vegetation, mainly in the Cerrado and Caatinga provinces of the Brazilian Shield (southeastern, northeastern and central-western regions), occurring mainly above 900 m asl. up to altitudes exceeding 2000 m, having measured annual precipitation between 800 and 1500 mm, and an arid season of two to five months.

Options for the disposition of current inventory of Rocky Flats Plant residues

International Nuclear Information System (INIS)

Chang, Lychin.

1994-01-01

With the end of the Cold War, much concern has been directed towards the accumulation of special nuclear material resulting from the dismantlement of a large number of nuclear weapons. This concern has opened up a debate over the final disposition of the large inventory of weapons-capable plutonium. Technologies for the conversion of plutonium into acceptable forms will need to be assessed and evaluated. Candidate strategies for interim and final disposition include a variety of immobilization techniques (vitrification in glass, ceramic, or metal), conversion to reactor fuel, or direct discard as waste. The selected disposition strategy will be chosen based upon a range of decision metric such as expected conversion costs, equipment requirements, and waste generation. To this end, a systems analysis approach is necessary for the evaluation and comparison of the different disposition strategies. Current data on inventory of plutonium, such as that at the Rocky Flats Plant (RFP), may be useful for the evaluation and selection of candidate disposition technologies. A preliminary analysis of the residues of scrap at Rocky Flats was performed to establish a foundation for comparison of candidate strategies. About 3 metric tons of plutonium and 270 metric tons of other wastes remain in the inventory at Rocky Flats. Estimates on the equipment, facility, manpower, and cost requirements to process this inventory over a proposed 10-year cleanup campaign will provide a benchmark for comparison and assessment of proposed disposition technologies

Influence of tubificid worms on nutrient fluxes across water-sediment interface in fish farm settling ponds

Directory of Open Access Journals (Sweden)

Puigagut J.

2014-04-01

Full Text Available The influence of tubificid worms on nutrient translocation from water to fish farm sediments accumulating in settling ponds was addressed under laboratory conditions. Small microcosms of 0.5 L were filled up with 35 g of sludge from a fish farm settling pond and 0.15 L of filtered settling pond water. The experimental set up consisted of one control line (no worms added, a second experimental line with 1 mg of tubificid worms·g-1 fresh sediment (550 individuals·m-2 and a third experimental line with 40 mg of tubificid worms·g-1 fresh sediment (22 000 individuals·m-2. Nutrients translocation was determined by monitoring overlaying water concentration of ammonia, nitrate and phosphate for ten days. Results showed that abundances of 550 individuals·m-2 had no significant influence on the fluxes of nutrients here considered. However, the influence of higher abundances of tubificids (22 000 individuals·m-2 was of significant extent on the translocation of nitrate and phosphate. Accordingly, bioturbation of tubificids caused 55% lower nitrate uptake by the sediment when compared to control conditions. Phosphorus released by the sediments of the control condition was ca. 90% higher than that recorded under abundances of tubificids (22 000 individuals·m-2. Results obtained allowed us to estimate that fish farm settling ponds highly colonized by tubificid worms (22 000 individuals·m-2 may contribute to decrease phosphorus discharge (in terms of soluble phosphorus in ca. 5 g of P·ton-1 of fish produced.

Compaction-Driven Evolution of Pluto's Rocky Core: Implications for Water-Rock Interactions

Science.gov (United States)

Gabasova, L. R.; Tobie, G.; Choblet, G.

2018-05-01

We model the compaction of Pluto's rocky core after accretion and explore the potential for hydrothermal circulation within the porous layer, as well as examine its effect on core cooling and the persistence of a liquid internal ocean.

Rocky Flats Environmental Technology Site Ecological Monitoring Program 1995 annual report

International Nuclear Information System (INIS)

1995-01-01

The Ecological Monitoring Program (ECMP) was established at the Rocky Flats Environmental Technology Site (Site) in September 1992. At that time, EcMP staff developed a Program Plan that was peer-reviewed by scientists from western universities before submittal to DOE RFFO in January 1993. The intent of the program is to measure several quantitative variables at different ecological scales in order to characterize the Rocky Flats ecosystem. This information is necessary to document ecological conditions at the Site in impacted and nonimpacted areas to determine if Site practices have had ecological impacts, either positive or negative. This information can be used by managers interested in future use scenarios and CERCLA activities. Others interested in impact analysis may also find the information useful. In addition, these measurements are entered into a database which will serve as a long-term information repository that will document long-term trends and potential future changes to the Site, both natural and anthropogenic

239Pu contamination in snakes inhabiting the Rocky Flats Plant site

International Nuclear Information System (INIS)

Geiger, R.A.; Winsor, T.F.

1975-01-01

For approximately four years studies have been under way at the Rocky Flats plant to determine contamination patterns and concentrations of Pu in the biota. Contamination of the Rocky Flats environs has resulted from at least three incidents, a September 1957 fire, a May 1969 fire, and leaking barrels containing plutonium-laden cutting oil. The latter incident was considered by far the major source of the plutonium contamination. Results are reported from a study conducted to determine whether snake tissues of the area contained detectable amounts of 239 Pu and, if so, at what concentrations. Eastern yellow-bellied racers (Coluber constrictor flaviventris, bullsnakes (Pituophis melanoleucus sayi, and prairie rattlesnakes (Crotalus viridis viridis, were collected for 239 Pu bioassay of lung, liver, and bone tissues. Snakes were captured using drift fences terminating in funnel traps and by opportunistic sampling. Results led to the conclusion that snakes are not an important organism in the redistribution of 239 Pu

Reactive barrier technologies for treatment of contaminated groundwater at Rocky Flats

International Nuclear Information System (INIS)

Marozas, D.C.; Bujewski, G.E.; Castaneda, N.

1997-01-01

The U.S. Department of Energy (DOE) Office of Science and Technology Subsurface Contaminants Focus Area is supporting the investigation of reactive barrier technologies to mitigate the risks associated with mixed organic/radioactive waste at several DOE sites. Groundwater from a small contaminated plume at the Rocky Flats Environmental Technology Site (RFETS) is being used to evaluate passive reactive material treatment. Permeable reactive barriers which intercept contaminants and destroy the VOC component while containing radionuclides are attractive for a number of reasons relating to public and regulatory acceptance. In situ treatment keeps contaminants away from the earth's surface, there is no above-ground treatment equipment that could expose workers and the public and operational costs are expected to be lower than currently used technologies. This paper will present results from preliminary site characterization and in-field small-scale column testing of reactive materials at RFETS. Successful demonstration is expected to lead to full-scale implementation of the technology at several DOE sites, including Rocky Flats

Rocky Flats Environmental Technology Site Ecological Monitoring Program 1995 annual report

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-05-31

The Ecological Monitoring Program (ECMP) was established at the Rocky Flats Environmental Technology Site (Site) in September 1992. At that time, EcMP staff developed a Program Plan that was peer-reviewed by scientists from western universities before submittal to DOE RFFO in January 1993. The intent of the program is to measure several quantitative variables at different ecological scales in order to characterize the Rocky Flats ecosystem. This information is necessary to document ecological conditions at the Site in impacted and nonimpacted areas to determine if Site practices have had ecological impacts, either positive or negative. This information can be used by managers interested in future use scenarios and CERCLA activities. Others interested in impact analysis may also find the information useful. In addition, these measurements are entered into a database which will serve as a long-term information repository that will document long-term trends and potential future changes to the Site, both natural and anthropogenic.

Outbreak of Rocky Mountain spotted fever in Córdoba, Colombia

Directory of Open Access Journals (Sweden)

Marylin Hidalgo

2011-02-01

Full Text Available Rocky Mountain spotted fever (RMSF is a tick-borne disease caused by the obligate intracellular bacterium Rickettsia rickettsii. Although RMSF was first reported in Colombia in 1937, it remains a neglected disease. Herein, we describe the investigation of a large cluster of cases of spotted fever rickettsiosis in a new area of Colombia.

Rocky Flats Plant Site Environmental Report: 1993 Highlights

Energy Technology Data Exchange (ETDEWEB)

1993-12-31

The Rocky Flats Plant Site Environmental Report provides summary information on the plant`s environmental monitoring programs and the results recorded during 1993. The report contains a compliance summary, results of environmental monitoring and other related programs, a review of environmental remediation activities, information on external gamma radiation dose monitoring, and radiation dose estimates for the surrounding population. This section provides an overview of these topics and summarizes more comprehensive discussions found in the main text of this annual report.

Characterization and radionuclides sorption of suspended particulate matters in freshwater according to their settling kinetics

International Nuclear Information System (INIS)

Brach-Papa, C.; Boyer, P.; Amielh, M.; Anselmet, F.

2004-01-01

In freshwater, the transfers of radionuclides depend both on exchanges between liquid and solid phases and on mass transfers between suspended matter and bottom sediment. Whereas the former ones depend on chemical processes (such as sorption/desorption, complexation, the latter ones are regulated by hydrological and sedimentary considerations (dispersion, erosion, deposit closely related to the interactions between flow, suspended matter and bed sediment. Some of our previous studies highlight the need to consider the matter heterogeneity and its specific sediment dynamics to correctly report the inhomogeneity of fluxes in time and in space. These considerations lead us to develop experimental methods to distinguish the different matter classes, present in natural water, mainly according to their erosion threshold and settling kinetics. In this context, this paper presents the experimental protocol TALISMEN to characterize a natural bulk suspension according the identification of its main settling kinetics groups. In a first step, this identification is achieved by the use of a settling tank, that allows the monitoring of the suspended solid concentration at various depths, combined to a vertical mono-dimensional settling model applying a multi-class approach. In a second step, the particle groups are isolated and their physico-chemical properties are determined ( i.e mineral composition, specific surface area, particulate organic carbon, in order to fully characterized them. In a last one, the sorption property of each group toward radionuclides is determined by the measurements of its distribution coefficients (Kd). The results confirm the interest to consider these heterogeneities for the modelling of the radionuclides transfer in freshwater. From one group to other, these heterogeneities appear at two levels: 1) their sediment dynamics and 2) their radionuclides sorption properties. These conclusions can be equally applying to others xenobiotics as heavy metals

Cow allergen (Bos d2) and endotoxin concentrations are higher in the settled dust of homes proximate to industrial-scale dairy operations.

Science.gov (United States)

Williams, D' Ann L; McCormack, Meredith C; Matsui, Elizabeth C; Diette, Gregory B; McKenzie, Shawn E; Geyh, Alison S; Breysse, Patrick N

2016-01-01

Airborne contaminants produced by industrial agricultural facilities contain chemical and biological compounds that can impact the health of residents living in close proximity. Settled dust can be a reservoir for these contaminants and can influence long-term exposures. In this study, we sampled the indoor- and outdoor-settled dust from 40 homes that varied in proximity to industrial-scale dairies (ISD; industrial-scale dairy, a term used in this paper to describe a large dairy farm and adjacent waste sprayfields, concentrated animal feeding operation or animal feeding operation, that uses industrial processes) in the Yakima Valley, Washington. We analyzed settled dust samples for cow allergen (Bos d2, a cow allergen associated with dander, hair, sweat and urine, it is a member of the lipocalin family of allergens associated with mammals), mouse allergen (Mus m1; major mouse allergen, a mouse urinary allergen, in the lipocalin family), dust mite allergens (Der p1 (Dermatophagoides pteronissinus 1) and Der f1 (Dermatophagoides farinae 1)), and endotoxin (a component of the cell walls of gram negative bacteria, lipopolysaccharide, which can be found in air and dust and can produce a strong inflammatory response). A concentration gradient was observed for Bos d2 and endotoxin measured in outdoor-settled dust samples based on proximity to ISD. Indoor-settled dust concentrations of Bos d2 and endotoxin were also highest in proximal homes. While the associated health effects of exposure to cow allergen in settled dust is unknown, endotoxin at concentrations observed in these proximal homes (100 EU/mg) has been associated with increased negative respiratory health effects. These findings document that biological contaminants emitted from ISDs are elevated in indoor- and outdoor-settled dust samples at homes close to these facilities and extend to as much as three miles (4.8 km) away.

DOE awards first economic conversion project at Rocky Flats

International Nuclear Information System (INIS)

Lobsenz, G.

1993-01-01

In the first economic conversion project at an Energy Department weapons facility, a Colorado company this week was given permission to refurbish four buildings at DOE's Rocky Flats plant to recycle slightly radioactive scrap metal. DOE, acting in conjunction with the Environmental Protection Agency and Colorado authorities, announced Tuesday it had given the go-ahead to Manufacturing Sciences Corp. of Golden, Colorado, to proceed with planning for the project

Endotoxin levels in settled airborne dust in European schools : The HITEA school study

NARCIS (Netherlands)

Jacobs, J. H.; Krop, E. J M; Borras-Santos, A.; Zock, J. P.; Taubel, M.; Hyvarinnen, A.; Pekkanen, J.; Doekes, G.; Heederik, D. J J

2014-01-01

Indoor exposure to microbial agents is known to influence respiratory health. Besides home exposure, exposure in schools can affect respiratory health. In this study, we measured endotoxin in settled dust in primary schools in three European countries from three different geographical regions with

Prehistoric human settling on the Tibetan Plateau

Science.gov (United States)

Chen, F.; Zhang, D.; Dong, G.; Xia, H.

2017-12-01

When and where did human first settle down on the Tibetan Plateau is under hot debate among archaeologist, anthropologists, geneticist and paleo-geographers. Based on systematic archaeological, chronological and archaeo-botanical studies of 53 sites in Northeastern Tibetan Plateau, we propose that agriculture facilitated human permanent settlement on the Tibetan Plateau initially since 5200 years ago below 2500 masl and since 3600 years ago up to around 4000 masl, possibly assisted by domesticated animals (Chen et al. 2015). By redating the age of hand- and footprints in Chusang site in Tibet, Meyer et al. (2017) argue that hunter-gatherers permanently occupied central Tibetan Plateau in early Holocene (before 7.4 ka) without the help of agriculture. Except for the possible problem of dating, however, the limited hand- and footprints could only indicate the presence of prehistoric hunter-gatherers on the remote central Tibetan Plateau in the early Holocene, unable to support the permanent inhabitation assertion (Zhang et al., 2017). To better understand how human spread to, settle on and adapt to the Tibetan Plateau, we are closely working together with anthropologists, archaeologists and geneticists to do system Paleolithic surveys, full excavations, and genetic analysis of ancient and modern human, animals and plants. Our preliminary study show that human migrated to the Tibetan Plateau from the last Deglacial period to late Holocene mainly from North China via Yellow River valley and its tributary valleys in the Northeastern Tibetan Plateau (NETP). This migration is constituted of four stages (Upper Paleolithic, Epi-Paleolithic, Neolithic and Bronze Age) with different adaptation strategies, including microlithic technology, millet and barley farming, and sheep herding and so on (Zhang et al., 2016). In addition, our new finds in Tibet indicate that there are probably more migration routes from southeast and southwest Tibetan Plateau in the late Pleistocene or

Movements and habitat use of rocky mountain elk and mule deer.

Science.gov (United States)

Alan A. Ager; Haiganoush K. Preisler; Bruce K. Johnson; John G. Kie

2004-01-01

Understanding how ungulates use large landscapes to meet their daily needs for food, security and other resources is critical to wildlife management and conservation practices (Johnson et al. 2002). For ungulates like Rocky Mountain elk (Gems elaphui) and mule deer (Odocoileus hemionus), landscapes are a mosaic of different...

A Fatal Urban Case of Rocky Mountain Spotted Fever Presenting an Eschar in San José, Costa Rica

Science.gov (United States)

Argüello, Ana Patricia; Hun, Laya; Rivera, Patricia; Taylor, Lizeth

2012-01-01

This study reports the first urban human case of Rocky Mountain spotted fever caused by Rickettsia rickettsii, in Costa Rica. An 8-year-old female who died at the National Children's Hospital 4 days after her admission, and an important and significant observation was the presence of an “eschar” (tache noire), which is typical in some rickettsial infections but not frequent in Rocky Mountain spotted fever cases. PMID:22855769

A Fatal Urban Case of Rocky Mountain Spotted Fever Presenting an Eschar in San José, Costa Rica

OpenAIRE

Argüello, Ana Patricia; Hun, Laya; Rivera, Patricia; Taylor, Lizeth

2012-01-01

This study reports the first urban human case of Rocky Mountain spotted fever caused by Rickettsia rickettsii, in Costa Rica. An 8-year-old female who died at the National Children's Hospital 4 days after her admission, and an important and significant observation was the presence of an “eschar” (tache noire), which is typical in some rickettsial infections but not frequent in Rocky Mountain spotted fever cases.

Esthetic evaluation of timber harvesting in the Northern Rockies - a progressive report

Science.gov (United States)

Dennis L. Schweitzer; James R. Ullrich; Robert E. Benson

1976-01-01

Panels of judges have been evaluating the esthetic dimension of harvested areas in the Northern Rockies. Studies conducted in Wyoming and Montana agree with intuition in that forest scenes are generally liked less as the evidence of man's activities increases.

Vegetation of the coastal fynbos and rocky headlands south of George, South Africa

Directory of Open Access Journals (Sweden)

D. B. Hoare

2000-02-01

Full Text Available Community structure and composition of the coastal fynbos and rocky headland plant communities south of George, southern Cape, were studied. Vegetation was analysed using standard sampling procedures of the floristic-sociological approach of Braun-Blanquet. The releve data were subject to TWIN SPAN-based divisive classification, and ordinated by Principal Coordinates Analysis with the aim to identify vegetation coenocline subsequently interpreted in terms of under­lying environmental gradients. Most of the sampled vegetation was classified as coastal fynbos. The  Leucadendron salignum-Tetraria cuspidata Fynbos Community was found to occupy sheltered habitats, whereas the  Relhania calyci- na-Passerina vulgaris Fynbos Community was found in exposed habitats The other two communities characterise strong­ly exposed rocky headlands. The Pterocelastrus tricuspidatus-Ruschia tenella Community is wind-sheared scrub, and the Gazania rigens- Limonium scabrum Rocky Headland Community is a loose-canopy, low-grown herbland, characterised by the occurrence of partly salt-tolerant and succulent herbs. The ordination of the fynbos communities revealed a horseshoe structure allowing a direct recognition of a coenocline spanning two fynbos communities along the Axis 1 interpreted in terms of exposure to wind and salt spray. A considerable amount of alien plant infestation was also present. This appears to be the largest threat to the continued existence of this coastal fynbos.

What's new in Rocky Mountain spotted fever?

Science.gov (United States)

Chen, Luke F; Sexton, Daniel J

2008-09-01

Rocky Mountain spotted fever (RMSF) remains an important illness despite an effective therapy because it is difficult to diagnose and is capable of producing a fatal outcome. The pathogenesis of RMSF remains, in large part, an enigma. However, recent research has helped shed light on this mystery. Importantly, the diagnosis of RMSF must be considered in all febrile patients who have known or possible exposure to ticks, especially if they live in or have traveled to endemic regions during warmer months. Decisions about giving empiric therapy to such patients are difficult and require skill and careful judgement.

Stable isotopes in yellow-bellied marmot (Marmota flaviventris) fossils reveal environmental stability in the late Quaternary of the Colorado Rocky Mountains

Science.gov (United States)

Reynard, Linda M.; Meltzer, David J.; Emslie, Steven D.; Tuross, Noreen

2015-03-01

High elevation plant and animal communities are considered extremely sensitive to environmental change. We investigated an exceptional fossil record of yellow-bellied marmot (Marmota flaviventris) specimens that was recovered from Cement Creek Cave (elev. 2860 m) and ranged in age from radiocarbon background circa 49.8 cal ka BP to ~ 1 cal ka BP. We coupled isotopic and radiocarbon measurements (δ18O, δD, δ15N, δ13C, and 14C) of bone collagen from individually-AMS dated specimens of marmots to assess ecological responses by this species to environmental change over time in a high elevation basin in the Rocky Mountains of southwestern Colorado, USA. We find little change in all four isotope ratios over time, demonstrating considerable environmental stability during periods when the marmots were present. The stable ecology and the apparent persistence of the small mammal community in the cave fauna throughout the late Quaternary are in marked contrast to the changes that occurred in the large mammal community, including local extirpation and extinction, at the end of the Pleistocene.

La/Yb and Th/Sc in settling particles: vertical and horizontal transport of lithogenic material in the western North Pacific

International Nuclear Information System (INIS)

Otosaka, Shigeyoshi; Noriki, Shinichiro; Honda, Makio C.

2004-01-01

In order to understand the origins and transport processes of lithogenic aluminosilicate in the western North Pacific, time-series traps were deployed at Stn. KNOT at 44degN 155degE (water depth: 5320 m). Annual mean content of aluminum (Al) which is a proxy of lithogenic material in settling particles was 0.38% at 1 km depth, 0.78% at 3 km depth and 1.14% at 5 km depth, respectively. Mass fluxes were corrected by 230 Th and 231 Pa activities in particles and seawater. Annual mean corrected Al fluxes at 1, 3 and 5 km depths were calculated to 0.45, 0.46 and 0.33 g/m 2 /year, respectively. Lanthanum/ytterbium (La/Yb) and thorium/scandium (Th/Sc) ratios were used as proxies for estimating the origin of lithogenic aluminosilicate in settling particles. Both La/Yb and Th/Sc ratios in settling particles increased with depth, and the seasonal variation was the smallest at 5 km depth. It was considered that variations of La/Yb and Th/Sc ratios in settling particles reflected the change of source material of lithogenic aluminosilicates. Origins of lithogenic materials in the settling particles were summarized using two end-members, loess from central Asian continent (AL) and basalts from the Kurile-Kamchatka Islands (KEK). Contributions of end-members in settling particles were estimated from the La/Yb and Th/Sc ratios. The contribution of KK particles in lithogenic materials was calculated to be 84% at 1 km depth, and 61% at 3 and 5 km depths, respectively. Although the KK material was the dominant constituent of the terrigenous component in settling particles at Stn. KNOT, the KK flux decreased with depth. On the other hand, the AL flux increased with depth and the significant increase of the AL flux was presumably due to the lateral import of AL particles to the deep layer at Stn. KNOT. From these results we conclude that the distribution of lithogenic materials recorded in sediments in the western North Pacific are influenced by the northward transport of AL within the

Holocene sea-level change and the emergence of Neolithic seafaring in the Fuzhou Basin (Fujian, China)

Science.gov (United States)

Rolett, Barry V.; Zheng, Zhuo; Yue, Yuanfu

2011-04-01

Neolithic seafaring across the Taiwan Strait began approximately 5000 years ago and involved open-sea voyages over distances of at least 130 km. Rapid sea-level rise preceded the emergence of open-sea voyaging, but the possible role of environmental change as a stimulus for the development of seafaring is poorly understood. We investigate this problem by presenting a record of Holocene sea-level change and coastal transformation based on sediment cores obtained from the Fuzhou Basin on the coast of Fujian, China. The cores are located in direct proximity to archaeological sites of the Tanshishan Neolithic culture (5000-4300 cal BP), which is significant for its similarity to the earliest Neolithic cultures of Taiwan. Multiple lines of evidence record the early Holocene inundation of the Fuzhou Basin around 9000 cal BP, the mid-Holocene sea-level highstand, and the final Holocene marine transgression. This final transition is precisely documented, with AMS dates showing the change occurred close to 1900 cal BP. Our paleogeographic reconstruction shows that a large estuary filled the Fuzhou Basin during the mid-Holocene. Tanshishan and Zhuangbianshan, two of the major Fuzhou Basin Neolithic sites, are located today on hills nearly 80 km from the modern coastline. However, when the sites were settled around 5500-5000 cal BP, the marine transgression had transformed these hills into islands in the upper estuary. We suggest that the Neolithic era estuary setting, together with the lack of land suitable for rice paddy agriculture, inhibited intensive food production but favored a maritime orientation and the development of seafaring.

Enhanced settling of nonheavy inertial particles in homogeneous isotropic turbulence: The role of the pressure gradient and the Basset history force.

Science.gov (United States)

van Hinsberg, M A T; Clercx, H J H; Toschi, F

2017-02-01

The Stokes drag force and the gravity force are usually sufficient to describe the behavior of sub-Kolmogorov-size (or pointlike) heavy particles in turbulence, in particular when the particle-to-fluid density ratio ρ_{p}/ρ_{f}≳10^{3} (with ρ_{p} and ρ_{f} the particle and fluid density, respectively). This is, in general, not the case for smaller particle-to-fluid density ratios, in particular not for ρ_{p}/ρ_{f}≲10^{2}. In that case the pressure gradient force, added mass effects, and the Basset history force also play important roles. In this study we focus on the understanding of the role of these additional forces, all of hydrodynamic origin, in the settling of particles in turbulence. In order to qualitatively elucidate the complex dynamics of such particles in homogeneous isotropic turbulence, we first focus on the case of settling of such particles in the flow field of a single vortex. After having explored this simplified case we extend our analysis to homogeneous isotropic turbulence. In general, we found that the pressure gradient force leads to a decrease in the settling velocity. This can be qualitatively understood by the fact that this force prevents the particles from sweeping out of vortices, a mechanism known as preferential sweeping which causes enhanced settling. Additionally, we found that the Basset history force can both increase and decrease the enhanced settling, depending on the particle Stokes number. Finally, the role of the nonlinear Stokes drag has been explored, confirming that it affects settling of inertial particles in turbulence, but only in a limited way for the parameter settings used in this investigation.

Climatology of summer midtropospheric perturbations in the US northern plains. Part II: large-scale effects of the Rocky Mountains on genesis

Energy Technology Data Exchange (ETDEWEB)

Wang, Shih-Yu. [Iowa State University, Department of Geological and Atmospheric Sciences, Ames, IA (United States); Utah State University, Utah Climate Center, Logan, UT (United States); Chen, Tsing-Chang [Iowa State University, Department of Geological and Atmospheric Sciences, Ames, IA (United States); Takle, Eugene S. [Iowa State University, Department of Geological and Atmospheric Sciences, Ames, IA (United States); Iowa State University, Department of Agronomy, Ames, IA (United States)

2011-04-15

Propagating convective storms across the US northern plains are often coupled with preexisting midtropospheric perturbations (MPs) initiated over the Rocky Mountains. A companion study (Part I) notes that such MPs occur most commonly at 12 UTC (early morning) and 00 UTC (late afternoon). Using a regional reanalysis and a general circulation model (GCM), this study investigates how such a bimodal distribution of the MP frequency is formed. The results point to two possible mechanisms working together while each has a different timing in terms of maximum effect. The diurnal evolutions between the midtropospheric flows over the Rockies and over the Great Plains are nearly out-of-phase due to inertial oscillation. During the nighttime, the westerly flows at 700-500 mb over the Rockies intensify while flows at the same level over the Great Plains turn easterly. These two flows converge over the eastern Rockies and induce cyclonic vorticity through vortex stretching. After sunrise, the convergence dissipates and the cyclonic vorticity is redistributed by horizontal vorticity advection, moving it downstream. This process creates a climatological zonally propagating vorticity signal which, in turn, facilitates the early-morning MP genesis at 12 UTC. The analysis also reveals marked dynamic instability conducive to subsynoptic-scale disturbances in the midtroposphere over the Rockies. Strong meridional temperature gradients appear over the north-facing slopes of the Rockies due to terrain heating to the south and the presence of cooler air to the north. This feature, along with persistent vertical shear, creates a Charney-Stern type of instability (i.e. sign changes of the meridional potential vorticity gradient). Meanwhile, the development of terrain boundary layer reduces the Rossby deformation radius which, subsequently, enhances the likelihood for baroclinic short waves. Such effects are most pronounced in the late afternoon and therefore are supportive to the MP

TANK 21 AND TANK 24 BLEND AND FEED STUDY: BLENDING TIMES, SETTLING TIMES, AND TRANSFERS

Energy Technology Data Exchange (ETDEWEB)

Lee, S.; Leishear, R.; Poirier, M.

2012-05-31

The Salt Disposition Integration (SDI) portfolio of projects provides the infrastructure within existing Liquid Waste facilities to support the startup and long term operation of the Salt Waste Processing Facility (SWPF). Within SDI, the Blend and Feed Project will equip existing waste tanks in the Tank Farms to serve as Blend Tanks where salt solutions of up to 1.2 million gallons will be blended in 1.3 million gallon tanks and qualified for use as feedstock for SWPF. In particular, Tanks 21 and 24 are planned to be used for blending and transferring to the SDI feed tank. These tanks were evaluated here to determine blending times, to determine a range of settling times for disturbed sludge, and to determine that the SWPF Waste Acceptance Criteria that less than 1200 mg/liter of solids will be entrained in salt solutions during transfers from the Tank 21 and Tank 24 will be met. Overall conclusions for Tank 21 and Tank 24 operations include: (1) Experimental correction factors were applied to CFD (computational fluid dynamics) models to establish blending times between approximately two and five hours. As shown in Phase 2 research, blending times may be as much as ten times greater, or more, if lighter fluids are added to heavier fluids (i.e., water added to salt solution). As the densities of two salt solutions converge this effect may be minimized, but additional confirmatory research was not performed. (2) At the current sludge levels and the presently planned operating heights of the transfer pumps, solids entrainment will be less than 1200 mg/liter, assuming a conservative, slow settling sludge simulant. (3) Based on theoretical calculations, particles in the density range of 2.5 to 5.0 g/mL must be greater than 2-4 {micro}m in diameter to ensure they settle adequately in 30-60 days to meet the SWPF feed criterion (<1200 mg/l). (4) Experimental tests with sludge batch 6 simulant and field turbidity data from a recent Tank 21 mixing evolution suggest the solid

Lessons for Integrated Water Resources Management from the San Pedro HELP Basin on the U.S.-Mexico Border

Science.gov (United States)

Browning, A.; Goodrich, D.; Varady, R.; Richter, H.

2007-12-01

The San Pedro Basin sits within an intermountain ecotone with the Sonoran and Chihuahuan Deserts to the west and east and the Rocky Mountain and Sierra Madre Mountain habitats to the north and south. The headwaters of the basin originate in northern Sonora and flow north into southeast Arizona. As the region's only remaining perennial stream, the San Pedro River serves as an international flyway for over 400 bird species. It is one of the western hemisphere's most ecologically diverse areas with some 20 different biotic communities, and "possesses one of the richest assemblages of land mammal species in the world." Large mining, military, and municipal entities are major users of the same groundwater resources that maintain perennial flow in the San Pedro. This presentation describes empirical evidence of the positive impacts on watershed management of scientists and policy researchers working closely with water managers and elected officials in a functioning HELP basin. We posit that when hydrologists help watershed groups understand the processes controlling water quality and quantity, and when managers and stakeholders connect these processes to social, economic and legal issues then transboundary cooperation in policymaking and water management is most effective. The distinctive physical and socioeconomic characteristics of the basin as well as differences in institutional regulations, water law issues, and their local implementations in Arizona and Sonora are discussed. We illustrate how stakeholders and scientific researchers in both countries strive to balance ecosystem needs with human demands to create new, integrated basin management. Finally, we describe how the accomplishments of the San Pedro collaborative process, including the use of environmental-conflict-resolution tools, have contributed to the UNESCO HELP (Hydrology for the Environment, Life, and Policy) agenda.

Immune Thrombocytopenia as a Consequence of Rocky Mountain Spotted Fever.

Science.gov (United States)

Baldeo, Cherisse; Seegobin, Karan; Zuberi, Lara

2017-01-01

Primary immune thrombocytopenia (ITP) - also called idiopathic thrombocytopenic purpura or immune thrombocytopenic purpura - is an acquired thrombocytopenia caused by autoantibodies against platelet antigens. It is one of the more common causes of thrombocytopenia in otherwise asymptomatic adults. Rocky Mountain spotted fever (RMSF) is a potentially lethal, but curable, tick-borne disease. We present a case of ITP that was triggered by RMSF.

The Tunas Formation (Permian) in the Sierras Australes foldbelt, east central Argentina: evidence for syntectonic sedimentation in a foreland basin

Science.gov (United States)

Lopez-Gamundi, O. R.; Conaghan, P. J.; Rossello, E. A.; Cobbold, P. R.

1995-04-01

The Tunas Formation, extensively exposed in the Sierras Australes foldbelt of eastern central Argentina, completes the sedimentation of the Gondwanan (Late Carboniferous-Permian) sequence, locally known as the Pillahuincó Group. The underlying units of the Group show an integrated depositional history which can be explained in terms of glaciomarine sedimentation (Sauce Grande Formation) and postglacial transgression (Piedra Azul and Bonete Formations). This succession also has a rather uniform quartz-rich, sand-sized composition indicative of a cratonic provenance from the Tandilia Massif to the northeast. Early to Late Permian deformation folded and thrusted the southwestern basin margin (Sierras Australes) and triggered the deposition of a 1,500 m — thick, synorogenic prograding wedge, the Tunas Formation, in the adjacent foreland basin (Sauce Grande or Claromecó Basin). Sandstone detrital modes for the Tunas deposits show moderate to low contents of quartz and abundant lithics, mostly of volcanic and metasedimentary origin. Paleocurrents are consistently from the SW. Tuffs interbedded with sandstones in the upper half of Tunas Formation (Early — early Late? Permian) are interpreted as being derived from volcanic glass-rich tuffs settled in a body of water. Extensive rhyolitic ignimbrites and consanguineous airborne tuffaceous material erupted in the northern Patagonian region during that period. The age constraints and similarities in composition between these volcanics and the tuffaceous horizons present in the Sauce Grande, Parana and Karoo Basins suggest a genetic linkage between these two episodes. The intimate relationship between volcanic activity inboard of the paleo-Pacific margin, deformation in the adjacent orogenic belt and subsidence and sedimentation in the contiguous foreland basin constitutes a common motif in the Sauce Grande and Karoo Basins of southwestern Gondwana.

Distribution of macroinvertebrates on intertidal rocky shores in Gorgona Island, Colombia (Tropical Eastern Pacific

Directory of Open Access Journals (Sweden)

Edgardo Londoño-Cruz

2014-02-01

Full Text Available Organisms found on rocky shores must endure harsh environmental conditions during tidal changes but scientific studies on tropical rocky shores are scarce, particularly in Colombian shores. Here we describe the spatial distribution of macroinvertebrates associated to the intertidal rocky ecosystems of Gorgona Island, Colombia (Tropical Eastern Pacific. Sampling was carried out in four localities around the Island: La Ventana and La Camaronera (sampled during October 2010 and La Mancora and El Muelle (sampled during March 2011. Two methodologies were used: rapid ecological assessments for qualitative data and quadrats for quantitative data. The richness, abundance, diversity (Shannon-Wiener H’, and evenness (Pielou J’ of macroinvertebrates were determined for and compared between, using one way ANOVA, each locality and the three intertidal zones of La Ventana (see methods. One hundred twenty-one species of macroinvertebrates were found during the sampling period. In all localities, Mollusca was the richest and most abundant taxon (46% of the species and 59% of the individuals, followed by Crustacea (32% of the species and 33% of the individuals. The other groups accounted for the remaining 22% of the richness and 8% of the abundance. Several studies have demonstrated that mollusks and crustaceans are the richest and most abundant taxa in marine benthic communities. Most of the abundant species found were herbivores. The species composition varied among zones. The results of dominant species for each zone are consistent with the ones observed in other tropical rocky intertidal shores. All response variables showed a decreasing pattern from the low to the high intertidal (in La Ventana. Post-hoc results indicated that the high intertidal, the zone with the harshest environmental conditions, had significantly lower values than the other two zones for all response variables. Comparisons between the low intertidal zones of the different localities

Hydraulic evolution of high-density turbidity currents from the Brushy Canyon Formation, Eddy County, New Mexico inferred by comparison to settling and sorting experiments

Science.gov (United States)

Motanated, Kannipa; Tice, Michael M.

2016-05-01

Hydraulic transformations in turbidity currents are commonly driven by or reflected in changes in suspended sediment concentrations, but changes preceding transformations can be difficult to diagnose because they do not produce qualitative changes in resultant deposits. This study integrates particle settling experiments and in situ detection of hydraulically contrasting particles in turbidites in order to infer changes in suspended sediment concentration during deposition of massive (Bouma Ta) sandstone divisions. Because grains of contrasting density are differentially sorted during hindered settling from dense suspensions, relative grading patterns can be used to estimate suspended sediment concentrations and interpret hydraulic evolution of the depositing turbidity currents. Differential settling of dense particles (aluminum ballotini) through suspensions of hydraulically coarser light particles (silica ballotini) with volumetric concentration, Cv, were studied in a thin vessel by using particle-image-velocimetry. At high Cv, aluminum particles were less retarded than co-sedimenting silica particles, and effectively settled as hydraulically coarser grains. This was because particles were entrained into clusters dominated by the settling behavior of the silica particles. Terminal settling velocities of both particles converged at Cv ≥ 25%, and particle sorting was diminished. The results of settling experiments were applied to understand settling of analogous feldspar and zircon grains in natural turbidity flows. Distributions of light and heavy mineral grains in massive sandstones, Bouma Ta divisions, of turbidites from the Middle Permian Brushy Canyon Formation were observed in situ by X-ray fluorescence microscopy (μXRF). Hydraulic sorting of these grains resulted in characteristic patterns of zirconium abundance that decreased from base to top within Ta divisions. These profiles resulted from upward fining of zircon grains with respect to co

Quantitative detection of settled dust over green canopy

Science.gov (United States)

Brook, Anna

2016-04-01

The main task of environmental and geoscience applications are efficient and accurate quantitative classification of earth surfaces and spatial phenomena. In the past decade, there has been a significant interest in employing hyperspectral unmixing in order to retrieve accurate quantitative information latent in hyperspectral imagery data. Recently, the ground-truth and laboratory measured spectral signatures promoted by advanced algorithms are proposed as a new path toward solving the unmixing problem of hyperspectral imagery in semi-supervised fashion. This paper suggests that the sensitivity of sparse unmixing techniques provides an ideal approach to extract and identify dust settled over/upon green vegetation canopy using hyperspectral airborne data. Atmospheric dust transports a variety of chemicals, some of which pose a risk to the ecosystem and human health (Kaskaoutis, et al., 2008). Many studies deal with the impact of dust on particulate matter (PM) and atmospheric pollution. Considering the potential impact of industrial pollutants, one of the most important considerations is the fact that suspended PM can have both a physical and a chemical impact on plants, soils, and water bodies. Not only can the particles covering surfaces cause physical distortion, but particles of diverse origin and different chemistries can also serve as chemical stressors and cause irreversible damage. Sediment dust load in an indoor environment can be spectrally assessed using reflectance spectroscopy (Chudnovsky and Ben-Dor, 2009). Small amounts of particulate pollution that may carry a signature of a forthcoming environmental hazard are of key interest when considering the effects of pollution. According to the most basic distribution dynamics, dust consists of suspended particulate matter in a fine state of subdivision that are raised and carried by wind. In this context, it is increasingly important to first, understand the distribution dynamics of pollutants, and

Numerical Modeling of Rocky Mountain Paleoglaciers - Insights into the Climate of the Last Glacial Maximum and the Subsequent Deglaciation

Science.gov (United States)

Leonard, E. M.; Laabs, B. J. C.; Plummer, M. A.

2014-12-01

Numerical modeling of paleoglaciers can yield information on the climatic conditions necessary to sustain those glaciers. In this study we apply a coupled 2-d mass/energy balance and flow model (Plummer and Phillips, 2003) to reconstruct local last glacial maximum (LLGM) glaciers and paleoclimate in ten study areas along the crest of the U.S. Rocky Mountains between 33°N and 49°N. In some of the areas, where timing of post-LLGM ice recession is constrained by surface exposure ages on either polished bedrock upvalley from the LLGM moraines or post-LLGM recessional moraines, we use the model to assess magnitudes and rates of climate change during deglaciation. The modeling reveals a complex pattern of LLGM climate. The magnitude of LLGM-to-modern climate change (temperature and/or precipitation change) was greater in both the northern (Montana) Rocky Mountains and southern (New Mexico) Rocky Mountains than in the middle (Wyoming and Colorado) Rocky Mountains. We use temperature depression estimates from global and regional climate models to infer LLGM precipitation from our glacier model results. Our results suggest a reduction of precipitation coupled with strongly depressed temperatures in the north, contrasted with strongly enhanced precipitation and much more modest temperature depression in the south. The middle Rocky Mountains of Colorado and Wyoming appear to have experienced a reduction in precipitation at the LLGM without the strong temperature depression of the northern Rocky Mountains. Preliminary work on modeling of deglaciation in the Sangre de Cristo Range in southern Colorado suggests that approximately half of the LLGM-to-modern climate change took place during the initial ~2400 years of deglaciation. If increasing temperature and changing solar insolation were the sole drivers of this initial deglaciation, then temperature would need to have risen by slightly more than 1°C/ky through this interval to account for the observed rate of ice recession.

Factors governing the ability of clean-up plant to remove settling particles from contaminants: theory for stable particles

International Nuclear Information System (INIS)

Longworth, J.P.

1979-11-01

Consideration is given to the processes by which particles are removed from fluid systems. In particular, it is noted that in tank, as opposed to loop, systems the natural process of gravitational settling competes with engineered removal systems. Calculational methods are given for estimating the relative amounts of settling and removal to clean-up plant for well-mixed fluids, unmixed fluids with horizontal or vertical flow, and turbulent diffusion with incomplete mixing. The criteria for complete mixing are discussed. (author)

The analysis of morphometric data on rocky mountain wolves and artic wolves using statistical method

Science.gov (United States)

Ammar Shafi, Muhammad; Saifullah Rusiman, Mohd; Hamzah, Nor Shamsidah Amir; Nor, Maria Elena; Ahmad, Noor’ani; Azia Hazida Mohamad Azmi, Nur; Latip, Muhammad Faez Ab; Hilmi Azman, Ahmad

2018-04-01

Morphometrics is a quantitative analysis depending on the shape and size of several specimens. Morphometric quantitative analyses are commonly used to analyse fossil record, shape and size of specimens and others. The aim of the study is to find the differences between rocky mountain wolves and arctic wolves based on gender. The sample utilised secondary data which included seven variables as independent variables and two dependent variables. Statistical modelling was used in the analysis such was the analysis of variance (ANOVA) and multivariate analysis of variance (MANOVA). The results showed there exist differentiating results between arctic wolves and rocky mountain wolves based on independent factors and gender.

Spatial-temporal Evolution of Vegetation Coverage and Analysis of it’s Future Trends in Wujiang River Basin

Science.gov (United States)

Xiao, Jianyong; Bai, Xiaoyong; Zhou, Dequan; Qian, Qinghuan; Zeng, Cheng; Chen, Fei

2018-01-01

Vegetation coverage dynamics is affected by climatic, topography and human activities, which is an important indicator reflecting the regional ecological environment. Revealing the spatial-temporal characteristics of vegetation coverage is of great significance to the protection and management of ecological environment. Based on MODIS NDVI data and the Maximum Value Composites (MVC), we excluded soil spectrum interference to calculate Fractional Vegetation Coverage (FVC). Then the long-term FVC was used to calculate the spatial pattern and temporal variation of vegetation in Wujiang River Basin from 2000 to 2016 by using Trend analysis and Hurst index. The relationship between topography and spatial distribution of FVC was analyzed. The main conclusions are as follows: (1) The multi-annual mean vegetation coverage reveals a spatial distribution variation characteristic of low value in midstream and high level in other parts of the basin, owing a mean value of 0.6567. (2) From 2000 to 2016, the FVC of the Wujiang River Basin fluctuated between 0.6110 and 0.7380, and the overall growth rate of FVC was 0.0074/a. (3) The area of vegetation coverage tending to improve is more than that going to degrade in the future. Grass land, Arable land and Others improved significantly; karst rocky desertification comprehensive management project lead to persistent vegetation coverage improvement of Grass land, Arable land and Others. Residential land is covered with obviously degraded vegetation, resulting of urban sprawl; (4) The spatial distribution of FVC is positively correlated with TNI. Researches of spatial-temporal evolution of vegetation coverage have significant meaning for the ecological environment protection and management of the Wujiang River Basin.

Rickettsia parkeri rickettsiosis and its clinical distinction from Rocky Mountain spotted fever.

Science.gov (United States)

Paddock, Christopher D; Finley, Richard W; Wright, Cynthia S; Robinson, Howard N; Schrodt, Barbara J; Lane, Carole C; Ekenna, Okechukwu; Blass, Mitchell A; Tamminga, Cynthia L; Ohl, Christopher A; McLellan, Susan L F; Goddard, Jerome; Holman, Robert C; Openshaw, John J; Sumner, John W; Zaki, Sherif R; Eremeeva, Marina E

2008-11-01

Rickettsia parkeri rickettsiosis, a recently identified spotted fever transmitted by the Gulf Coast tick (Amblyomma maculatum), was first described in 2004. We summarize the clinical and epidemiological features of 12 patients in the United States with confirmed or probable disease attributable to R. parkeri and comment on distinctions between R. parkeri rickettsiosis and other United States rickettsioses. Clinical specimens from patients in the United States who reside within the range of A. maculatum for whom an eschar or vesicular rash was described were evaluated by > or =1 laboratory assays at the Centers for Disease Control and Prevention (Atlanta, GA) to identify probable or confirmed infection with R. parkeri. During 1998-2007, clinical samples from 12 patients with illnesses epidemiologically and clinically compatible with R. parkeri rickettsiosis were submitted for diagnostic evaluation. Using indirect immunofluorescence antibody assays, immunohistochemistry, polymerase chain reaction assays, and cell culture isolation, we identified 6 confirmed and 6 probable cases of infection with R. parkeri. The aggregate clinical characteristics of these patients revealed a disease similar to but less severe than classically described Rocky Mountain spotted fever. Closer attention to the distinct clinical features of the various spotted fever syndromes that exist in the United States and other countries of the Western hemisphere, coupled with more frequent use of specific confirmatory assays, may unveil several unique diseases that have been identified collectively as Rocky Mountain spotted fever during the past century. Accurate assessments of these distinct infections will ultimately provide a more valid description of the currently recognized distribution, incidence, and case-fatality rate of Rocky Mountain spotted fever.

Portrait of a Cult Film Audience: "The Rocky Horror Picture Show."

Science.gov (United States)

Austin, Bruce A.

1981-01-01

Examines the phenomenon of the cult film and the characteristics of the audiences of the "Rocky Horror Picture Show." Suggests that the preparation, waiting, and finally the active participation in the viewing of the film itself appear to be part of a group ritual which characterizes the cult film as an event. (JMF)

Characterizing climate-change impacts on the 1.5-yr flood flow in selected basins across the United States: a probabilistic approach

Science.gov (United States)

Walker, John F.; Hay, Lauren E.; Markstrom, Steven L.; Dettinger, Michael D.

2011-01-01

The U.S. Geological Survey Precipitation-Runoff Modeling System (PRMS) model was applied to basins in 14 different hydroclimatic regions to determine the sensitivity and variability of the freshwater resources of the United States in the face of current climate-change projections. Rather than attempting to choose a most likely scenario from the results of the Intergovernmental Panel on Climate Change, an ensemble of climate simulations from five models under three emissions scenarios each was used to drive the basin models. Climate-change scenarios were generated for PRMS by modifying historical precipitation and temperature inputs; mean monthly climate change was derived by calculating changes in mean climates from current to various future decades in the ensemble of climate projections. Empirical orthogonal functions (EOFs) were fitted to the PRMS model output driven by the ensemble of climate projections and provided a basis for randomly (but representatively) generating realizations of hydrologic response to future climates. For each realization, the 1.5-yr flood was calculated to represent a flow important for sediment transport and channel geomorphology. The empirical probability density function (pdf) of the 1.5-yr flood was estimated using the results across the realizations for each basin. Of the 14 basins studied, 9 showed clear temporal shifts in the pdfs of the 1.5-yr flood projected into the twenty-first century. In the western United States, where the annual peak discharges are heavily influenced by snowmelt, three basins show at least a 10% increase in the 1.5-yr flood in the twenty-first century; the remaining two basins demonstrate increases in the 1.5-yr flood, but the temporal shifts in the pdfs and the percent changes are not as distinct. Four basins in the eastern Rockies/central United States show at least a 10% decrease in the 1.5-yr flood; the remaining two basins demonstrate decreases in the 1.5-yr flood, but the temporal shifts in the pdfs

In situ holographic measurements of the sizes and settling rates of oceanic particulates

Science.gov (United States)

Carder, Kendall L.; Steward, Robert G.; Betzer, Peter R.

1982-07-01

A free-floating sediment trap equipped with a holographic particle velocimeter (HPV) was deployed for 14.4 hours at a depth of 30 m in the western North Atlantic Ocean. The system recorded the in situ sizes, shapes, orientations, and settling rates of microscopic particles moving through the laser beam. The primary data reduction revealed particles from the system's lower limit of resolution, 15 micrometers in diameter, to 250 micrometers in diameter with settling velocities ranging from 0.0190 to 0.2302 cm/s (16-198 m/day). Individual particle densities, calculated from a modified Stokes equation, ranged from 1.37 to 5.10 g/ml. The presence of high density particles was independently corroborated through individual particle analysis of the trapped material with a computer-controlled, scanning electron microscope equipped with an energy dispersive X-ray analyzer. In the future, in situ holographic systems might be used to further our understanding of primary productivity, sediment erosion/deposition, and particle aggregation/disruption/dissolution.

Stabilization of mixed waste - Rocky Flats solar ponds

International Nuclear Information System (INIS)

Bittner, T.A.; Mathew, S.A.; Henderson, W.C.

1993-01-01

Among the wastes that require disposal as part of the Department of Energy's (DOE's) Environmental Restoration Program are large amounts of contaminated sludge and inorganic wastes. Halliburton NUS Corporation was awarded a contract by EG ampersand G Rocky Flats in March 1991 to stabilize mixed waste sludge contained in five solar evaporator ponds and to reprocess billets of solidified waste called Pondcrete and Saltcrete at DOE's Rocky Flats Plant. The scope of the project consists of waste characterization and treatability studies for process development, followed by design, construction and operation of various process trains to remediate different waste forms ranging from solid Pondcrete/Saltcrete blocks to aqueous brine solutions. One of the significant advances made was the development of a durable and certifiable stabilization formulation capable of treating concentrated nitrate solution wastes. The project uses high-volume grout mixing and pumping technologies with process control techniques that accommodate the heterogeneity of the wastes. To comply with all relevant environmental regulations and to provide a safe working atmosphere for plant personnel, Halliburton NUS designed process trains such that all emissions were eliminated during the remediation process. Personnel protection equipment requirements have been downgraded due to safeguards incorporated in the design. The technical and regulatory issues that were encountered would be typical of stabilization efforts underway at other DOE sites. Thus the lessons learned and concepts developed can be expected to have widespread application

Vitrification of plutonium at Rocky Flats the argument for a pilot plant

Energy Technology Data Exchange (ETDEWEB)

Moore, L. [Rocky Mountain Peace Center, Boulder, CO (United States)

1996-05-01

Current plans for stabilizing and storing the plutonium at Rocky Flats Plant fail to put the material in a form suitable for disposition and resistant to proliferation. Vitrification should be considered as an alternate technology. The vitrification should begin with a small-scale pilot plant.

A preliminary survey of the cichlid fishes of rocky habitats in Lake ...

African Journals Online (AJOL)

given on some of the other rocky shore fishes particularly in the genus Cyrtocara. ... biology, numerical abundance and distribution. Indeed, ... some species have very limited distributions. Exporters of ..... Fishelson (1974) to describe the diversity of fishes at par- ..... zooplankton, phytoplankton, benthic Invertebrata, fish fry.

Strength Measurements of Archive K Basin Sludge Using a Soil Penetrometer

International Nuclear Information System (INIS)

Delegard, Calvin H.; Schmidt, Andrew J.; Chenault, Jeffrey W.

2011-01-01

Spent fuel radioactive sludge present in the K East and K West spent nuclear fuel storage basins now resides in the KW Basin in six large underwater engineered containers. The sludge will be dispositioned in two phases under the Sludge Treatment Project: (1) hydraulic retrieval into sludge transport and storage containers (STSCs) and transport to interim storage in Central Plateau and (2) retrieval from the STSCs, treatment, and packaging for shipment to the Waste Isolation Pilot Plant. In the years the STSCs are stored, sludge strength is expected to increase through chemical reaction, intergrowth of sludge crystals, and compaction and dewatering by settling. Increased sludge strength can impact the type and operation of the retrieval equipment needed prior to final sludge treatment and packaging. It is important to determine whether water jetting, planned for sludge retrieval from STSCs, will be effective. Shear strength is a property known to correlate with the effectiveness of water jetting. Accordingly, the unconfined compressive strengths (UCS) of archive K Basin sludge samples and sludge blends were measured using a pocket penetrometer modified for hot cell use. Based on known correlations, UCS values can be converted to shear strengths. Twenty-six sludge samples, stored in hot cells for a number of years since last being disturbed, were identified as potential candidates for UCS measurement and valid UCS measurements were made for twelve, each of which was found as moist or water-immersed solids at least 1/2-inch deep. Ten of the twelve samples were relatively weak, having consistencies described as 'very soft' to 'soft'. Two of the twelve samples, KE Pit and KC-4 P250, were strong with 'very stiff' and 'stiff' consistencies described, respectively, as 'can be indented by a thumb nail' or 'can be indented by thumb'. Both of these sludge samples are composites collected from KE Basin floor and Weasel Pit locations. Despite both strong sludges having

Strength Measurements of Archive K Basin Sludge Using a Soil Penetrometer

Energy Technology Data Exchange (ETDEWEB)

Delegard, Calvin H.; Schmidt, Andrew J.; Chenault, Jeffrey W.

2011-12-06

Spent fuel radioactive sludge present in the K East and K West spent nuclear fuel storage basins now resides in the KW Basin in six large underwater engineered containers. The sludge will be dispositioned in two phases under the Sludge Treatment Project: (1) hydraulic retrieval into sludge transport and storage containers (STSCs) and transport to interim storage in Central Plateau and (2) retrieval from the STSCs, treatment, and packaging for shipment to the Waste Isolation Pilot Plant. In the years the STSCs are stored, sludge strength is expected to increase through chemical reaction, intergrowth of sludge crystals, and compaction and dewatering by settling. Increased sludge strength can impact the type and operation of the retrieval equipment needed prior to final sludge treatment and packaging. It is important to determine whether water jetting, planned for sludge retrieval from STSCs, will be effective. Shear strength is a property known to correlate with the effectiveness of water jetting. Accordingly, the unconfined compressive strengths (UCS) of archive K Basin sludge samples and sludge blends were measured using a pocket penetrometer modified for hot cell use. Based on known correlations, UCS values can be converted to shear strengths. Twenty-six sludge samples, stored in hot cells for a number of years since last being disturbed, were identified as potential candidates for UCS measurement and valid UCS measurements were made for twelve, each of which was found as moist or water-immersed solids at least 1/2-inch deep. Ten of the twelve samples were relatively weak, having consistencies described as 'very soft' to 'soft'. Two of the twelve samples, KE Pit and KC-4 P250, were strong with 'very stiff' and 'stiff' consistencies described, respectively, as 'can be indented by a thumb nail' or 'can be indented by thumb'. Both of these sludge samples are composites collected from KE Basin floor and

Discrepancies in Weil-Felix and microimmunofluorescence test results for Rocky Mountain spotted fever.

Science.gov (United States)

Hechemy, K E; Stevens, R W; Sasowski, S; Michaelson, E E; Casper, E A; Philip, R N

1979-01-01

Only 4.2% of 284 single specimens and 17.6% of 51 pairs of sera reactive in Weil-Felix agglutination tests for Rocky Mountain spotted fever were confirmed by a specific Rickettsia rickettsii microimmunofluorescence test. PMID:107194

Recycling silicon wire-saw slurries: separation of silicon and silicon carbide in a ramp settling tank under an applied electrical field.

Science.gov (United States)

Tsai, Tzu-Hsuan; Shih, Yu-Pei; Wu, Yung-Fu

2013-05-01

The growing demand for silicon solar cells in the global market has greatly increased the amount of silicon sawing waste produced each year. Recycling kerf Si and SiC from sawing waste is an economical method to reduce this waste. This study reports the separation of Si and SiC using a ramp settling tank. As they settle in an electrical field, small Si particles with higher negative charges have a longer horizontal displacement than SiC particles in a solution of pH 7, resulting in the separation of Si and SiC. The agreement between experimental results and predicted results shows that the particles traveled a short distance to reach the collection port in the ramp tank. Consequently, the time required for tiny particles to hit the tank bottom decreased, and the interference caused by the dispersion between particles and the fluid motion during settling decreased. In the ramp tank, the highest purities of the collected SiC and Si powders were 95.2 and 7.01 wt%, respectively. Using a ramp tank, the recycling fraction of Si-rich powders (SiC tanks. Recycling Si and SiC abrasives from the silicon sawing waste is regarded as an economical solution to reduce the sawing waste. However, the separation of Si and SiC is difficult. This study reports the separation of Si and SiC using a ramp settling tank under an applied electrical field. As they settle in an electrical field, small Si particles with higher negative charges have a longer horizontal displacement than SiC particles in a solution of pH 7, resulting in the separation of Si and SiC. Compared with the rectangular tanks, the recycling fraction of Si-rich powders using a ramp tank is greater, and the proposed ramp settling tank is more suitable for industrial applications.

Review on physical and chemical characterizations of contaminated sediments from urban stormwater infiltration basins within the framework of the French observatory for urban hydrology (SOERE URBIS).

Science.gov (United States)

El-Mufleh, Amelène; Béchet, Béatrice; Ruban, Véronique; Legret, Michel; Clozel, Blandine; Barraud, Sylvie; Gonzalez-Merchan, Carolina; Bedell, Jean-Philippe; Delolme, Cécile

2014-04-01

Urban stormwater infiltration basins are designed to hold runoff from impervious surfaces and allow the settling of sediments and associated pollutants. However concerns have been expressed about the environmental impacts that may be exerted by the trapped pollutants on groundwater, soils and ecosystems. In this context, sediment characterization represents a key issue for local authorities in terms of management strategies. During the last two decades, several studies were launched including either physical or chemical characterization of stormwater sediments but without real synthesis of data and methods used. Consequently, there is an important need for reviewing the current experimental techniques devoted to the physico-chemical characterization of sediment. The review is based on the outcomes of two experimental sites for which long term monitoring and data collection have been done: the Cheviré basin (near Nantes) and the Django Reinhardt basin (near Lyon). The authors summarize the studies dealing with bulk properties, pollutant contents, their potential mobility and speciation. This paper aims at promoting the significant progresses that were made through a multidisciplinary approach involving multi-scaled and combined experimental techniques.

Integrated wastewater management planning for DOE's Rocky Flats Environmental Technology Site

International Nuclear Information System (INIS)

Hopkins, J.; Barthel, J.; Wheeler, M.; Conroy, K.

1996-01-01

Rocky Mountain Remediation Services, L.L.C. (RMRS), jointly formed by Morrison Knudsen Corporation and BNFL Inc., provides international experience in the nuclear, environmental, waste management, decontamination and decommissioning (D ampersand D) , and project management industry. The company is currently the environmental restoration, waste management, and D ampersand D subcontractor for Kaiser-Hill Company at the Rocky Flats Environmental Technology Site (RFETS). RMRS offers unique solutions and state-of-the-art technology to assist in resolving the issues that face industries today. RMRS has been working on methods to improve cost savings recognized at RFETS, through application of unique technologies and process engineering. RMRS prepared and is implementing a strategy that focused on identifying an approach to improve cost savings in current wastewater treatment systems and to define a low-cost, safe and versatile wastewater treatment system for the future. Development of this strategy, was targeted by Department of Energy (DOE) Headquarters, DOE Rocky Flats Field Office and Kaiser-Hill as a ''Project Breakthrough'' where old concepts were thrown out the door and the project goals and objectives were developed from the groundup. The objectives of the strategy developed in a project break through session with DOE included lower lifecycle costs, shutdown of one of two buildings at RFETS, Building 374 or Building 774, reduced government capital investment, and support of site closure program goals, identified as the site's Accelerated Site Action Plan (ASAP). The recommended option allows for removal of water treatment functions from Building 374, the existing process wastewater treatment facility. This option affords the lowest capital cost, lowest unit operating cost, lowest technical management risk, greatest support of ASAP phasing and provides the greatest flexibility for design with unforeseen future needs

Large-scale spatial distribution patterns of gastropod assemblages in rocky shores.

Directory of Open Access Journals (Sweden)

Patricia Miloslavich

Full Text Available Gastropod assemblages from nearshore rocky habitats were studied over large spatial scales to (1 describe broad-scale patterns in assemblage composition, including patterns by feeding modes, (2 identify latitudinal pattern of biodiversity, i.e., richness and abundance of gastropods and/or regional hotspots, and (3 identify potential environmental and anthropogenic drivers of these assemblages. Gastropods were sampled from 45 sites distributed within 12 Large Marine Ecosystem regions (LME following the NaGISA (Natural Geography in Shore Areas standard protocol (www.nagisa.coml.org. A total of 393 gastropod taxa from 87 families were collected. Eight of these families (9.2% appeared in four or more different LMEs. Among these, the Littorinidae was the most widely distributed (8 LMEs followed by the Trochidae and the Columbellidae (6 LMEs. In all regions, assemblages were dominated by few species, the most diverse and abundant of which were herbivores. No latitudinal gradients were evident in relation to species richness or densities among sampling sites. Highest diversity was found in the Mediterranean and in the Gulf of Alaska, while highest densities were found at different latitudes and represented by few species within one genus (e.g. Afrolittorina in the Agulhas Current, Littorina in the Scotian Shelf, and Lacuna in the Gulf of Alaska. No significant correlation was found between species composition and environmental variables (r≤0.355, p>0.05. Contributing variables to this low correlation included invasive species, inorganic pollution, SST anomalies, and chlorophyll-a anomalies. Despite data limitations in this study which restrict conclusions in a global context, this work represents the first effort to sample gastropod biodiversity on rocky shores using a standardized protocol across a wide scale. Our results will generate more work to build global databases allowing for large-scale diversity comparisons of rocky intertidal assemblages.

Spatial and temporal variation in sources of atmospheric nitrogen deposition in the Rocky Mountains using nitrogen isotopes

Science.gov (United States)

Nanus, Leora; Campbell, Donald H.; Lehmann, Christopher M. B.; Mast, M. Alisa

2018-03-01

Variation in source areas and source types of atmospheric nitrogen (N) deposition to high-elevation ecosystems in the Rocky Mountains were evaluated using spatially and temporally distributed N isotope data from atmospheric deposition networks for 1995-2016. This unique dataset links N in wet deposition and snowpack to mobile and stationary emissions sources, and enhances understanding of the impacts of anthropogenic activities and environmental policies that mitigate effects of accelerated N cycling across the Rocky Mountain region. δ15N-NO3- at 50 U.S. Geological Survey Rocky Mountain Snowpack (Snowpack) sites ranged from -3.3‰ to +6.5‰, with a mean value of +1.4‰. At 15 National Atmospheric Deposition Program (NADP)/National Trends Network wet deposition (NADP Wetfall) sites, summer δ15N-NO3- is significantly lower ranging from -7.6‰ to -1.3‰ while winter δ15N-NO3- ranges from -2.6‰ to +5.5‰, with a mean value of +0.7‰ during the cool season. The strong seasonal difference in NADP Wetfall δ15N-NO3- is due in part to variation in the proportion of N originating from source regions at different times of the year due to seasonal changes in weather patterns. Snowpack NO3- and δ15N-NO3- are significantly related to NADP Wetfall (fall and winter) suggesting that bulk snowpack samples provide a reliable estimate at high elevations. Spatial trends show higher NO3- concentrations and δ15N-NO3- in the Southern Rocky Mountains located near larger anthropogenic N emission sources compared to the Northern Rocky Mountains. NADP Wetfall δ15N-NH4+ ranged from -10‰ to 0‰, with no observed spatial pattern. However, the lowest δ15N-NH4+(-9‰), and the highest NH4+ concentration (35 μeq/L) were observed at a Utah site dominated by local agricultural activities, whereas the higher δ15N-NH4+ observed in Colorado and Wyoming are likely due to mixed sources, including fossil fuel combustion and agricultural sources. These findings show spatial and

Spatial and temporal variation in sources of atmospheric nitrogen deposition in the Rocky Mountains using nitrogen isotopes

Science.gov (United States)

Nanus, Leora; Campbell, Donald H.; Lehmann, Christopher M.B.; Mast, M. Alisa

2018-01-01

Variation in source areas and source types of atmospheric nitrogen (N) deposition to high-elevation ecosystems in the Rocky Mountains were evaluated using spatially and temporally distributed N isotope data from atmospheric deposition networks for 1995-2016. This unique dataset links N in wet deposition and snowpack to mobile and stationary emissions sources, and enhances understanding of the impacts of anthropogenic activities and environmental policies that mitigate effects of accelerated N cycling across the Rocky Mountain region. δ15N−NO3− at 50 U.S. Geological Survey Rocky Mountain Snowpack (Snowpack) sites ranged from −3.3‰ to +6.5‰, with a mean value of +1.4‰. At 15 National Atmospheric Deposition Program (NADP)/National Trends Network wet deposition (NADP Wetfall) sites, summer δ15N−NO3− is significantly lower ranging from −7.6‰ to −1.3‰ while winter δ15N−NO3− ranges from −2.6‰ to +5.5‰, with a mean value of +0.7‰ during the cool season. The strong seasonal difference in NADP Wetfall δ15N−NO3− is due in part to variation in the proportion of N originating from source regions at different times of the year due to seasonal changes in weather patterns. Snowpack NO3− and δ15N−NO3− are significantly related to NADP Wetfall (fall and winter) suggesting that bulk snowpack samples provide a reliable estimate at high elevations. Spatial trends show higher NO3−concentrations and δ15N−NO3− in the Southern Rocky Mountains located near larger anthropogenic N emission sources compared to the Northern Rocky Mountains. NADP Wetfall δ15N−NH4+ ranged from −10‰ to 0‰, with no observed spatial pattern. However, the lowest δ15N−NH4+(−9‰), and the highest NH4+ concentration (35 μeq/L) were observed at a Utah site dominated by local agricultural activities, whereas the higher δ15N−NH4+observed in Colorado and Wyoming are likely due to mixed sources, including fossil fuel combustion and

Logging residues in principal forest types of the Northern Rocky Mountains

Science.gov (United States)

Robert E. Benson; Joyce A. Schlieter

1980-01-01

An estimated 466 million ft 3 of forest residue material (nonmerchantable, 3 inches diameter and larger) is generated annually in the Northern Rocky Mountains (Montana, Idaho, Wyoming). Extensive studies of residues in the major forest types show a considerable portion is suited for various products. The lodgepole pine type has the greatest potential for increased...

Hydrological system dynamics of glaciated Karnali River Basin Nepal Himalaya using J2000 Hydrological model

Science.gov (United States)

Khatiwada, K. R.; Nepal, S.; Panthi, J., Sr.; Shrestha, M.

2015-12-01

Hydrological modelling plays an important role in understanding hydrological processes of a catchment. In the context of climate change, the understanding of hydrological characteristic of the catchment is very vital to understand how the climate change will affect the hydrological regime. This research facilitates in better understanding of the hydrological system dynamics of a himalayan mountainous catchment in western Nepal. The Karnali River, longest river flowing inside Nepal, is one of the three major basins of Nepal, having the area of 45269 sq. km. is unique. The basin has steep topography and high mountains to the northern side. The 40% of the basin is dominated by forest land while other land cover are: grass land, bare rocky land etc. About 2% of the areas in basin is covered by permanent glacier apart from that about 12% of basin has the snow and ice cover. There are 34 meteorological stations distributed across the basin. A process oriented distributed J2000 hydrologial model has been applied to understand the hydrological system dynamics. The model application provides distributed output of various hydrological components. The J2000 model applies Hydrological Response Unit (HRU) as a modelling entity. With 6861 HRU and 1010 reaches, the model was calibrated (1981-1999) and validated (2000-2004) at a daily scale using split-sample test. The model is able to capture the overall hydrological dynamics well. The rising limbs and recession limbs are simulated equally and with satisfactory ground water conditions. Based on the graphical and statistical evaluation of the model performance the model is able to simulate hydrological processes fairly well. Calibration shows that Nash Sutcliffe efficiency is 0.91, coefficient of determination is 0.92 Initial observation shows that during the pre-monsoon season(March to May) the glacial runoff is 25% of the total discharge while in the monsoon(June to September) season it is only 13%. The surface runoff

Immune Thrombocytopenia as a Consequence of Rocky Mountain Spotted Fever

OpenAIRE

Baldeo, Cherisse; Seegobin, Karan; Zuberi, Lara

2017-01-01

Primary immune thrombocytopenia (ITP) – also called idiopathic thrombocytopenic purpura or immune thrombocytopenic purpura – is an acquired thrombocytopenia caused by autoantibodies against platelet antigens. It is one of the more common causes of thrombocytopenia in otherwise asymptomatic adults. Rocky Mountain spotted fever (RMSF) is a potentially lethal, but curable, tick-borne disease. We present a case of ITP that was triggered by RMSF.

Immune Thrombocytopenia as a Consequence of Rocky Mountain Spotted Fever

Directory of Open Access Journals (Sweden)

Cherisse Baldeo

2017-10-01

Full Text Available Primary immune thrombocytopenia (ITP – also called idiopathic thrombocytopenic purpura or immune thrombocytopenic purpura – is an acquired thrombocytopenia caused by autoantibodies against platelet antigens. It is one of the more common causes of thrombocytopenia in otherwise asymptomatic adults. Rocky Mountain spotted fever (RMSF is a potentially lethal, but curable, tick-borne disease. We present a case of ITP that was triggered by RMSF.

Community Surveys Low Dose Radiation. Fernald, Ohio and Rocky Flats, Colorado

CERN Document Server

Mertz, C K; Johnson, S; MacGregor, D G; Satterfield, T

2002-01-01

This report is intended to present a basic description of the data from the two community surveys and to document the text of the questions; the methods used for the survey data collection; and a brief overview of the results. Completed surveys were conducted at local communities near the Rocky Flats, Colorado and the Fernald, Ohio sites; no survey was conducted for the Brookhaven, New York site. Fernald. The Fernald sample was randomly selected from 98% of all potential residential telephones in the townships of Ross, Morgan, and Crosby. The only telephone exchanges not used for the Fernald study had 4%, or fewer, of the holders of the telephone numbers actually living in either of the three target townships. Surveying started on July 24, 2001 and finished on August 30, 2001. A total of 399 completed interviews were obtained resulting in a CASRO response rate of 41.8%. The average length of an interview was 16.5 minutes. Rocky Flats. The sample was randomly selected from all potential residential telephones ...

Preventing the settling of salts of calcium and magnesium in oil production on the Boka oil field

Energy Technology Data Exchange (ETDEWEB)

Katincic, Z

1972-01-01

The results are given of laboratory and plant tests of the influence of sodium hexametaphosphate on the prevention of separation and settling of the salts of calcium and magnesium in the pipelines of the Boka oil field. All the former methods of fighting the salts consisted in dissolving the sediments of salt and paraffin in pipelines and the obligatory holding up of production, which required a loss in production in addition to material costs. By using the sodium hexametaphosphate, the settling of Ca and Mg salts in pipelines was prevented without holding up the production at considerably smaller cost.

Rocky Mountain spotted fever acquired in Florida, 1973-83.

Science.gov (United States)

Sacks, J J; Janowski, H T

1985-01-01

From 1973 to 1983, 49 Florida residents were reported with confirmed Rocky Mountain spotted fever (RMSF), 25 of whom were considered to have had Florida-acquired disease. Although there was no history of tick exposure for six of these 25 persons, all had contact with dogs or outdoor activities during the incubation period. The tick vectors of RMSF are widely distributed throughout Florida. We conclude that RMSF, although rare in Florida, can be acquired in the state. PMID:4061716

Desalination of effluent using fin type solar still

Energy Technology Data Exchange (ETDEWEB)

Velmurugan, V. [Department of Mechanical Engineering, Infant Jesus College of Engineering, Thoothukudi, Tamil Nadu 628 851 (India); Deenadayalan, C.K.; Vinod, H.; Srithar, K. [Department of Mechanical Engineering, Thiagarajar College of Engineering, Madurai, Tamil Nadu 625 015 (India)

2008-11-15

In this work, an attempt is made to produce potable water from industrial effluents. An ordinary basin type solar still integrated with fins at the basin plate is used for experimentation. Since industrial effluent is used as feed, before this still, an effluent settling tank is provided to get clarified effluent. This effluent settling tank is fabricated with three chambers, consists of pebble, coal and sand for settling the impurities and removing the bacteria in the effluents. Sponges, pebbles, black rubber and sand are used in the fin type single basin solar still for enhancing the yield. Results show that the productivity increases considerably due to this modification. A theoretical analysis is also carried out which, closely converges with experimental results. The economic analysis proved that the approximate payback period of such kinds of still is 1 year. (author)

The marriage of RCRA and CERCLA at the Rocky Flats Environmental Technology Site

International Nuclear Information System (INIS)

Shelton, D.C.; Brooks, L.M.

1998-01-01

A key goal of the Rocky Flats Cleanup Agreement (RFCA) signed in July of 1996 was to provide a seamless marriage of the Resource Conservation and Recovery Act (RCRA) (and other media specific programs) and the Comprehensive Environmental Response, Compensation and Liability Act (CERCLA) and the implementing agencies of each. This paper examines the two years since the signing of RFCA and identifies the successes, failures, and stresses of the marriage. RFCA has provided an excellent vehicle for regulatory and substantive progress at the Department of Energy's Rocky Flats facility. The key for a fully successful marriage is to build on the accomplishments to date and to continually improve the internal and external systems and relationships. To date, the parties can be proud of both the substantial accomplishment of substantive environmental work and the regulatory systems that have enabled the work

The Ogaden Basin, Ethiopia: an underexplored sedimentary basin

Energy Technology Data Exchange (ETDEWEB)

Teitz, H.H.

1991-01-01

A brief article examines the Ogaden Basin in Ethiopia in terms of basin origin, basin fill and the hydrocarbon exploration history and results. The natural gas find in pre-Jurassic sandstones, which appears to contain substantial reserves, justifies continuing investigations in this largely underexplored basin. (UK).

/sup 239/Pu contamination in snakes inhabiting the Rocky Flats Plant site

Energy Technology Data Exchange (ETDEWEB)

Geiger, R.A.; Winsor, T.F.

1975-01-01

For approximately four years studies have been under way at the Rocky Flats plant to determine contamination patterns and concentrations of Pu in the biota. Contamination of the Rocky Flats environs has resulted from at least three incidents, a September 1957 fire, a May 1969 fire, and leaking barrels containing plutonium-laden cutting oil. The latter incident was considered by far the major source of the plutonium contamination. Results are reported from a study conducted to determine whether snake tissues of the area contained detectable amounts of /sup 239/Pu and, if so, at what concentrations. Eastern yellow-bellied racers (Coluber constrictor flaviventris, bullsnakes (Pituophis melanoleucus sayi, and prairie rattlesnakes (Crotalus viridis viridis, were collected for /sup 239/Pu bioassay of lung, liver, and bone tissues. Snakes were captured using drift fences terminating in funnel traps and by opportunistic sampling. Results led to the conclusion that snakes are not an important organism in the redistribution of /sup 239/Pu. (CH)

Using GIS mapping of the extent of nearshore rocky reefs to estimate the abundance and reproductive output of important fishery species.

Directory of Open Access Journals (Sweden)

Jeremy T Claisse

Full Text Available Kelp Bass (Paralabrax clathratus and California Sheephead (Semicossyphus pulcher are economically and ecologically valuable rocky reef fishes in southern California, making them likely indicator species for evaluating resource management actions. Multiple spatial datasets, aerial and satellite photography, underwater observations and expert judgment were used to produce a comprehensive map of nearshore natural rocky reef habitat for the Santa Monica Bay region (California, USA. It was then used to examine the relative contribution of individual reefs to a regional estimate of abundance and reproductive potential of the focal species. For the reefs surveyed for fishes (i.e. 18 out of the 22 in the region, comprising 82% the natural rocky reef habitat 30% was produced from a relatively small proportion of the regional reef area (c. 10%. Natural nearshore rocky reefs make up only 11% of the area in the newly designated MPAs in this region, but results provide some optimism that regional fisheries could benefit through an increase in overall reproductive output, if adequate increases in size structure of targeted species are realized.

Isotopic composition of rainfall and runoff in a small arid basin with implications for deep percolation

Energy Technology Data Exchange (ETDEWEB)

Dody, A [Ben-Gurion Univ. of the Negev, Beersheba (Israel)

1995-08-01

The aim of this work was to characterize the isotopic composition of potential recharge in an arid rocky watershed. Unique field observations were obtained from an arid watershed in the Negev Highlands, Israel, through utilization of the dynamic variations in the isotopic composition of rainfall and runoff. The hydrological system`s inputs are rainfall and its isotopic composition. Rainfall and runoff were sampled in eight storms. High variability in the isotopic composition of rainfall was observed during any single rainstorm. The isotopic distribution in the runoff at the outlet of the basin appeared often not to be correlated to the isotopic patterns of the associated rain storm. A new mathematical model was developed to describe these physical processes. The model called A Double-Component Kinematic Wave Flow and Transport Approach, was designated to assess the dynamic isotopic distribution in arid rain storms and runoff. This model simulates the transport of rainfall into overland flow and runoff in an arid rocky watershed with uniformly distributed shallow depression storage. A numerical solution for the problem was developed, to estimate the depression storage parameters. The model also reflects the isotopic memory effect due to the depression storage between sequential rain showers. A good agreement between the observed and computed hydrograph and the change of the {delta}{sup 18O} values in runoff in time confirms the validity of the model. (author) 138 figs., 125 refs.

Seasonal Patterns of Dry Deposition at a High-Elevation Site in the Colorado Rocky Mountains

Science.gov (United States)

Oldani, Kaley M.; Mladenov, Natalie; Williams, Mark W.; Campbell, Cari M.; Lipson, David A.

2017-10-01

In the Colorado Rocky Mountains, high-elevation barren soils are deficient in carbon (C) and phosphorus (P) and enriched in nitrogen (N). The seasonal variability of dry deposition and its contributions to alpine elemental budgets is critical to understanding how dry deposition influences biogeochemical cycling in high-elevation environments. In this 2 year study, we evaluated dry and wet deposition inputs to the Niwot Ridge Long Term Ecological Research (NWT LTER) site in the Colorado Rocky Mountains. The total organic C flux in wet + dry (including soluble and particulate C) deposition was >30 kg C ha-1 yr-1 and represents a substantial input for this C-limited environment. Our side-by-side comparison of dry deposition collectors with and without marble insert indicated that the insert improved retention of dry deposition by 28%. Annual average dry deposition fluxes of water-soluble organic carbon (4.25 kg C ha-1 yr-1) and other water-soluble constituents, including ammonium (0.16 kg NH4+ha-1 yr-1), nitrate (1.99 kg NO3- ha-1 yr-1), phosphate (0.08 kg PO43- ha-1 yr-1), and sulfate (1.20 kg SO42- ha-1 yr-1), were comparable to those in wet deposition, with highest values measured in the summer. Backward trajectory analyses implicate air masses passing through the arid west and Four Corners, USA, as dominant source areas for dry deposition, especially in spring months. Synchronous temporal patterns of deposition observed at the NWT LTER site and a distant Rocky Mountain National Park Clean Air Status and Trends Network site indicate that seasonal dry deposition patterns are regional phenomena with important implications for the larger Rocky Mountain region.

Geology of uranium deposits in the southern part of the Rocky Mountain province of Colorado

International Nuclear Information System (INIS)

Malan, R.C.

1983-07-01

This report summarizes the geology of uranium deposits in the southern part of the Rocky Mountains of Colorado, an area of about 20,000 square miles. In January 1966, combined ore reserves and ore production at 28 uranium deposits were about 685,000 tons of ore averaging 0.24 percent U 3 O 8 (3.32 million pounds U 3 O 8 ). About half of these deposits each contain <1,000 tons of ore. The two largest deposits, the Pitch in the Marshall Pass locality southwest of Salida and the T-1 in the Cochetopa locality southeast of Gunnison, account for about 90 percent of all production and available reserves. The probability in excellent for major expansion of reserves in Marshall Pass and is favorable at a few other vein localities. There are six types of uranium deposits, and there were at least four ages of emplacement of these deposits in the southern part of the Colorado Rockies. There are eight types of host rocks of eight different ages. Veins and stratiform deposits each account for about 40 percent of the total number of deposits, but the veins of early and middle Tertiary age account for nearly all of the total reserves plus production. The remaining 20 percent of the deposits include uraniferous pegmatites, irregular disseminations in porphyry, and other less important types. The wall rocks at the large Tertiary vein deposits in the southern part of the Rocky Mountains of Colorado are Paleozoic and Mesozoic sedimentary rocks, whereas Precambrian metamorphic wall rocks predominate at the large veins in the Front Range of the northern Colorado Rockies. Metallogenetic considerations and tectonic influences affecting the distribution of uranium in Colorado and in adjacent portions of the western United States are analyzed

Particle size: a missing factor in risk assessment of human exposure to toxic chemicals in settled indoor dust.

Science.gov (United States)

Cao, Zhi-Guo; Yu, Gang; Chen, Yong-Shan; Cao, Qi-Ming; Fiedler, Heidelore; Deng, Shu-Bo; Huang, Jun; Wang, Bin

2012-11-15

For researches on toxic chemicals in settled indoor dust, selection of dust fraction is a critical influencing factor to the accuracy of human exposure risk assessment results. However, analysis of the selection of dust fraction in recent studies revealed that there is no consensus. This study classified and presented researches on distribution of toxic chemicals according to dust particle size and on relationship between dust particle size and human exposure possibility. According to the literature, beyond the fact that there were no consistent conclusions on particle size distribution of adherent fraction, dust with particle size less than 100 μm should be paid more attention and that larger than 250 μm is neither adherent nor proper for human exposure risk assessment. Calculation results based on literature data show that with different selections of dust fractions, analytical results of toxic chemicals would vary up to 10-fold, which means that selecting dust fractions arbitrarily will lead to large errors in risk assessment of human exposure to toxic chemicals in settled dust. Taking into account the influence of dust particle size on risk assessment of human exposure to toxic chemicals, a new methodology for risk assessment of human exposure to toxic chemicals in settled indoor dust is proposed and human exposure parameter systems to settled indoor dust are advised to be established at national and regional scales all over the world. Copyright © 2012 Elsevier Ltd. All rights reserved.

Fault Dating in the US Rockies and Large Regional Extent of Deformation Pulses Along the Sevier Orogen of North America.

Science.gov (United States)

van der Pluijm, B.; Lynch, E. A.; Pana, D.; Yonkee, A.

2017-12-01

Recent Ar dating of clay-rich fault rock in the Canadian Rockies identified multiple orogenic pulses: Late Jurassic (163-146 Ma), Mid-Cretaceous (103-99 Ma), Late Cretaceous (76-72 Ma) and Eocene (54-52 Ma; Pana and van der Pluijm, GSAB 2015). New dating in the US Rockies combined with ages in the most frontal section along an Idaho-Wyoming transect show a remarkably similar age pattern: Meade Thrust, 108-102 Ma; (S)Absaroka Thrust, 73 Ma; Darby-Bear Thrust, 56-50 Ma. These radiometric fault ages in the US Rockies match field and tectono-stratigraphic predictions, analogues to those in the Canadian Rockies. Thus, a remarkably long (>1500km) lateral tract along the North American Sevier orogen is characterized by at least three major orogenic pulses that are structurally contiguous. These orogenic pulses are progressively younger in the direction of easterly thrust fault motion (toward cratonic interior) and are separated by long periods of relative tectonic quiescence. We interpret the extensive regional continuity of deformation pulses and tectonic quiescence along the Sevier Orogen as the result of three plate reorganization events in western North America since the Late Jurassic.

Low crested coastal defence structures on the Catalan coast of the Mediterranean Sea: how they compare with natural rocky shores

Directory of Open Access Journals (Sweden)

Esperança Gacia

2007-06-01

Full Text Available Erosion problems in coastal zones are increasingly threatening Mediterranean shores. In tourist areas such as the Catalan coast, there has been an increasing demand for the construction of low crested structures (LCS to maintain beaches for recreational purposes. We studied the composition of the biota from three LCS and compared it with that of nearby natural rocky shores. Our purpose was to assess the composition of the communities growing on the LCS at a regional scale and to explore potential patterns of community composition in LCS in relation to the nature of the surrounding coast (i.e. sand or rocky shore, distance from natural hard-bottom communities and orientation of the blocks within the structure. The communities growing on the LCS were similar to those from nearby natural shores but the diversity and the number of taxa was always lower. Sixty to 95% of the species present on natural rocky shores grew on LCS, and differences in the number of taxa between the natural and the artificial substrates increased with increasing distances between them. On the Catalan coast, LCS act as impoverished rocky shores that never become natural ‘climax’ communities.

Tank 21 and Tank 24 Blend and Feed Study: Blending Times, Settling Times, and Transfers

International Nuclear Information System (INIS)

Lee, S.; Leishear, R.; Poirier, M.

2012-01-01

The Salt Disposition Integration (SDI) portfolio of projects provides the infrastructure within existing Liquid Waste facilities to support the startup and long term operation of the Salt Waste Processing Facility (SWPF). Within SDI, the Blend and Feed Project will equip existing waste tanks in the Tank Farms to serve as Blend Tanks where salt solutions of up to 1.2 million gallons will be blended in 1.3 million gallon tanks and qualified for use as feedstock for SWPF. In particular, Tanks 21 and 24 are planned to be used for blending and transferring to the SDI feed tank. These tanks were evaluated here to determine blending times, to determine a range of settling times for disturbed sludge, and to determine that the SWPF Waste Acceptance Criteria that less than 1200 mg/liter of solids will be entrained in salt solutions during transfers from the Tank 21 and Tank 24 will be met. Overall conclusions for Tank 21 and Tank 24 operations include: (1) Experimental correction factors were applied to CFD (computational fluid dynamics) models to establish blending times between approximately two and five hours. As shown in Phase 2 research, blending times may be as much as ten times greater, or more, if lighter fluids are added to heavier fluids (i.e., water added to salt solution). As the densities of two salt solutions converge this effect may be minimized, but additional confirmatory research was not performed. (2) At the current sludge levels and the presently planned operating heights of the transfer pumps, solids entrainment will be less than 1200 mg/liter, assuming a conservative, slow settling sludge simulant. (3) Based on theoretical calculations, particles in the density range of 2.5 to 5.0 g/mL must be greater than 2-4 (micro)m in diameter to ensure they settle adequately in 30-60 days to meet the SWPF feed criterion ( 60 days) settling times in Tank 21.

The Department of Energy's Rocky Flats Plant: A guide to record series useful for health related research. Volume 4: Production and materials handling

International Nuclear Information System (INIS)

1995-01-01

This is the fourth in a series of seven volumes which constitute a guide to records of the Rocky Flats Plant useful for conducting health-related research. The primary purpose of Volume 4 is to describe record series pertaining to production and materials handling activities at the Department of Energy's (DOE) Rocky Flats Plant, now named the Rocky Flats Environmental Technology Site, near Denver, Colorado. History Associates Incorporated (HAI) prepared this guide as part of its work as the support services contractor for DOE's Epidemiologic Records Inventory Project. This introduction briefly describes the Epidemiologic Records Inventory Project and HAI's role in the project, provides a history of production and materials handling practices at Rocky Flats, and identifies organizations contributing to production and materials handling policies and activities. Other topics include the scope and arrangement of the guide and the organization to contact for access to these records

Whole-community facilitation regulates biodiversity on Patagonian rocky shores.

Directory of Open Access Journals (Sweden)

Brian R Silliman

Full Text Available Understanding the factors that generate and maintain biodiversity is a central goal in ecology. While positive species interactions (i.e., facilitation have historically been underemphasized in ecological research, they are increasingly recognized as playing important roles in the evolution and maintenance of biodiversity. Dominant habitat-forming species (foundation species buffer environmental conditions and can therefore facilitate myriad associated species. Theory predicts that facilitation will be the dominant community-structuring force under harsh environmental conditions, where organisms depend on shelter for survival and predation is diminished. Wind-swept, arid Patagonian rocky shores are one of the most desiccating intertidal rocky shores ever studied, providing an opportunity to test this theory and elucidate the context-dependency of facilitation.Surveys across 2100 km of southern Argentinean coastline and experimental manipulations both supported theoretical predictions, with 43 out of 46 species in the animal assemblage obligated to living within the matrices of mussels for protection from potentially lethal desiccation stress and predators having no detectable impact on diversity.These results provide the first experimental support of long-standing theoretical predictions and reveal that in extreme climates, maintenance of whole-community diversity can be maintained by positive interactions that ameliorate physical stress. These findings have important conservation implications and emphasize that preserving foundation species should be a priority in remediating the biodiversity consequences of global climate change.

Preparation of air-settled, roll-thinned phosphorus targets

CERN Document Server

Lozowski, W R

1999-01-01

Red sup 3 sup 1 P targets of 2.6 and 2.9 mg/cm sup 2+-0.1 mg/cm sup 2 with 1-cmx2-cm side dimensions were prepared for a nuclear mass measurement which required good thickness uniformity. The thinner target, with 50 mu g/cm sup 2 of gold flashed on both surfaces, withstood a 173-MeV alpha beam of 175 nA for 18 h. Adaptations will be described for an Indiana University Cyclotron Facility air-settling method used to distribute phosphorus powder, as well as the methods developed for subsequent pressing, roll thinning, and dry release to obtain self-supporting targets. An envelope of gold foil, in contact with the phosphorus during each step, was instrumental in the process.

The Yukon settlement settled little enough

Energy Technology Data Exchange (ETDEWEB)

Sillars, L.

1997-01-27

Northern Cross, a small Alberta oil company has discovered the first promising petroleum prospect in the Yukon Territories in three decades. However, the company is unable to proceed with construction and production because the aboriginal community of Old Crow alleged that the project endangers the famous Porcupine Caribou Herd, has international implications, and infringes on traditional Gwitchin Indian territory. The wells in question were originally drilled in the 1960s, but abandoned due to lack of infrastructure, and ongoing negotiations with native groups. In 1993 the federal government indicated that land claim issues were settled. Northern Cross was the first company in to resume work on the wells, since the Dempster Highway, built in the meantime, makes getting the oil out a much more feasible proposition. The delay in approving Northern Cross`s application revolves around the dispute about the location of the wells,i.e. are they situated on tribal land or on Crown Land. The Department of Indian and Northern Affairs is investigating the rival claims, and promises to have a ruling within 12 months.

Cell structures caused by settling particles in turbulent Rayleigh-Bénard convection

Science.gov (United States)

Lee, Changhoon; Park, Sangro

2016-11-01

Turbulent thermal convection is an important phenomenon frequently found in nature and industrial processes, often with laden particles. In the last several decades, the vast majority of studies have addressed single phase convective flow with focus on the scaling relation of flow parameters associated with heat transfer. Particle-laden Rayleigh-Bénard convection, however, has not been sufficiently studied. In this study, modulation of cell structures by settling particles in turbulent Rayleigh-Bénard convection in a doubly periodic square channel is investigated using direct numerical simulation with a point particle approach. Flow parameters are fixed at Rayleigh number=106, Prandtl number=0.7, the aspect ratio=6, and Froude number=0.19. We report from the simulations that settling heavy particles modulate irregular large-scale thermal plume structures into organized polygonal cell structures. Different shapes of flow structures are obtained for different particle diameters and mass loadings. We found that polygonal cell structures arise due to asymmetric feedback force exerted by particles onto hot and cold plumes. Increasing the number of particles augments the asymmetry and the polygonal cell structures become smaller, eventually going to the hexagonal structures.

CHEMISTRY OF A PROTOPLANETARY DISK WITH GRAIN SETTLING AND Lyα RADIATION

International Nuclear Information System (INIS)

Fogel, Jeffrey K. J.; Bethell, Thomas J.; Bergin, Edwin A.; Calvet, Nuria; Semenov, Dmitry

2011-01-01

We present results from a model of the chemical evolution of protoplanetary disks. In our models, we directly calculate the changing propagation and penetration of a high energy radiation field with Lyα radiation included. We also explore the effect on our models of including dust grain settling. We find that, in agreement with earlier studies, the evolution of dust grains plays a large role in determining how deep the UV radiation penetrates into the disk. Significant grain settling at the midplane leads to much smaller freeze-out regions and a correspondingly larger molecular layer, which leads to an increase in column density for molecular species such as CO, CN, and SO. The inclusion of Lyα radiation impacts the disk chemistry through specific species that have large photodissociation cross sections at 1216 A. These include HCN, NH 3 , and CH 4 , for which the column densities are decreased by an order of magnitude or more due to the presence of Lyα radiation in the UV spectrum. A few species, such as CO 2 and SO, are enhanced by the presence of Lyα radiation, but rarely by more than a factor of a few.

Historical Exposures to Chemicals at the Rocky Flats Nuclear Weapons Plant: A Pilot Retrospective Exposure Assessment

Energy Technology Data Exchange (ETDEWEB)

Robertson, Janeen Denise [Univ. of New Mexico, Albuquerque, NM (United States)

1999-02-01

In a mortality study of white males who had worked at the Rocky Flats Nuclear Weapons Plant between 1952 and 1979, an increased number of deaths from benign and unspecified intracranial neoplasms was found. A case-control study nested within this cohort investigated the hypothesis that an association existed between brain tumor death and exposure to either internally deposited plutonium or external ionizing radiation. There was no statistically significant association found between estimated radiation exposure from internally deposited plutonium and the development of brain tumors. Exposure by job or work area showed no significant difference between the cohort and the control groups. An update of the study found elevated risk estimates for (1) all lymphopoietic neoplasms, and (2) all causes of death in employees with body burdens greater than or equal to two nanocuries of plutonium. There was an excess of brain tumors for the entire cohort. Similar cohort studies conducted on worker populations from other plutonium handling facilities have not yet shown any elevated risks for brain tumors. Historically, the Rocky Flats Nuclear Weapons Plant used large quantities of chemicals in their production operations. The use of solvents, particularly carbon tetrachloride, was unique to Rocky Flats. No investigation of the possible confounding effects of chemical exposures was done in the initial studies. The objectives of the present study are to (1) investigate the history of chemical use at the Rocky Flats facility; (2) locate and analyze chemical monitoring information in order to assess employee exposure to the chemicals that were used in the highest volume; and (3) determine the feasibility of establishing a chemical exposure assessment model that could be used in future epidemiology studies.