WorldWideScience

Sample records for santiam water control

  1. Simulations of a hypothetical temperature control structure at Detroit Dam on the North Santiam River, northwestern Oregon

    Science.gov (United States)

    Buccola, Norman L.; Stonewall, Adam J.; Rounds, Stewart A.

    2015-01-01

    Water temperature models of Detroit Lake, Big Cliff Lake, and the North Santiam River in northwestern Oregon were used to assess the potential for a hypothetical structure with variable intake elevations and an internal connection to power turbines at Detroit Dam (scenario SlidingWeir) to release more natural, pre-dam temperatures year round. This hypothetical structure improved outflow temperature control from Detroit Dam while meeting minimum dry-season release rates and lake levels specified by the rule curve specified for Detroit Lake.

  2. Simulating future water temperatures in the North Santiam River, Oregon

    Science.gov (United States)

    Buccola, Norman; Risley, John C.; Rounds, Stewart A.

    2016-01-01

    A previously calibrated two-dimensional hydrodynamic and water-quality model (CE-QUAL-W2) of Detroit Lake in western Oregon was used in conjunction with inflows derived from Precipitation-Runoff Modeling System (PRMS) hydrologic models to examine in-lake and downstream water temperature effects under future climate conditions. Current and hypothetical operations and structures at Detroit Dam were imposed on boundary conditions derived from downscaled General Circulation Models in base (1990–1999) and future (2059–2068) periods. Compared with the base period, future air temperatures were about 2 °C warmer year-round. Higher air temperature and lower precipitation under the future period resulted in a 23% reduction in mean annual PRMS-simulated discharge and a 1 °C increase in mean annual estimated stream temperatures flowing into the lake compared to the base period. Simulations incorporating current operational rules and minimum release rates at Detroit Dam to support downstream habitat, irrigation, and water supply during key times of year resulted in lower future lake levels. That scenario results in a lake level that is above the dam’s spillway crest only about half as many days in the future compared to historical frequencies. Managing temperature downstream of Detroit Dam depends on the ability to blend warmer water from the lake’s surface with cooler water from deep in the lake, and the spillway is an important release point near the lake’s surface. Annual average in-lake and release temperatures from Detroit Lake warmed 1.1 °C and 1.5 °C from base to future periods under present-day dam operational rules and fill schedules. Simulated dam operations such as beginning refill of the lake 30 days earlier or reducing minimum release rates (to keep more water in the lake to retain the use of the spillway) mitigated future warming to 0.4 and 0.9 °C below existing operational scenarios during the critical autumn spawning period for endangered

  3. Simulating future water temperatures in the North Santiam River, Oregon

    Science.gov (United States)

    Buccola, Norman L.; Risley, John C.; Rounds, Stewart A.

    2016-04-01

    A previously calibrated two-dimensional hydrodynamic and water-quality model (CE-QUAL-W2) of Detroit Lake in western Oregon was used in conjunction with inflows derived from Precipitation-Runoff Modeling System (PRMS) hydrologic models to examine in-lake and downstream water temperature effects under future climate conditions. Current and hypothetical operations and structures at Detroit Dam were imposed on boundary conditions derived from downscaled General Circulation Models in base (1990-1999) and future (2059-2068) periods. Compared with the base period, future air temperatures were about 2 °C warmer year-round. Higher air temperature and lower precipitation under the future period resulted in a 23% reduction in mean annual PRMS-simulated discharge and a 1 °C increase in mean annual estimated stream temperatures flowing into the lake compared to the base period. Simulations incorporating current operational rules and minimum release rates at Detroit Dam to support downstream habitat, irrigation, and water supply during key times of year resulted in lower future lake levels. That scenario results in a lake level that is above the dam's spillway crest only about half as many days in the future compared to historical frequencies. Managing temperature downstream of Detroit Dam depends on the ability to blend warmer water from the lake's surface with cooler water from deep in the lake, and the spillway is an important release point near the lake's surface. Annual average in-lake and release temperatures from Detroit Lake warmed 1.1 °C and 1.5 °C from base to future periods under present-day dam operational rules and fill schedules. Simulated dam operations such as beginning refill of the lake 30 days earlier or reducing minimum release rates (to keep more water in the lake to retain the use of the spillway) mitigated future warming to 0.4 and 0.9 °C below existing operational scenarios during the critical autumn spawning period for endangered salmonids. A

  4. Monitoring instream turbidity to estimate continuous suspended-sediment loads and yields and clay-water volumes in the upper North Santiam River Basin, Oregon, 1998-2000

    Science.gov (United States)

    Uhrich, Mark A.; Bragg, Heather M.

    2003-01-01

    Three real-time, instream water-quality and turbidity-monitoring sites were established in October 1998 in the upper North Santiam River Basin on the North Santiam River, the Breitenbush River, and Blowout Creek, the main tributary inputs to Detroit Lake, a large, controlled reservoir that extends from river mile 61 to 70. Suspended-sediment samples were collected biweekly to monthly at each station. Rating curves provided estimated suspended-sediment concentration in 30-minute increments from log transformations of the instream turbidity monitoring data. Turbidity was found to be a better surrogate than discharge for estimating suspended-sediment concentration. Daily and annual mean suspended-sediment loads were estimated using the estimated suspended-sediment concentrations and corresponding streamflow data. A laboratory method for estimating persistent (residual) turbidity from separate turbidity samples was developed. Turbidity was measured over time for each sample. Turbidity decay curves were derived as the suspended sediment settled. Each curve was used to estimate a turbidity value for a given settling time. Medium to fine clay particle (size clay particle persistent turbidity for each site. The monitored instream 30-minute turbidity values were converted to a calculated persistent turbidity value that would have resulted after 8.5 hours of settling in the laboratory. Persistent turbidities of 10 NTU and above were tabulated for each site. (Water of 10 NTU and above can interfere with or damage treatment filters and result in intake closures at drinking-water facilities.) A method was developed that used the persistent turbidity experiments, turbidity decay curves, and stream discharge to estimate the volume of water containing suspended clay that entered Detroit Lake from the three main tributaries. 'Suspended-clay water' was defined as water having a value of at least 10 NTU after settling the required 8.5 hours. The suspended-clay concentrations of 10

  5. Simulating potential structural and operational changes for Detroit Dam on the North Santiam River, Oregon, for downstream temperature management

    Science.gov (United States)

    Buccola, Norman L.; Rounds, Stewart A.; Sullivan, Annett B.; Risley, John C.

    2012-01-01

    Detroit Dam was constructed in 1953 on the North Santiam River in western Oregon and resulted in the formation of Detroit Lake. With a full-pool storage volume of 455,100 acre-feet and a dam height of 463 feet, Detroit Lake is one of the largest and most important reservoirs in the Willamette River basin in terms of power generation, recreation, and water storage and releases. The U.S. Army Corps of Engineers operates Detroit Dam as part of a system of 13 reservoirs in the Willamette Project to meet multiple goals, which include flood-damage protection, power generation, downstream navigation, recreation, and irrigation. A distinct cycle in water temperature occurs in Detroit Lake as spring and summer heating through solar radiation creates a warm layer of water near the surface and isolates cold water below. Controlling the temperature of releases from Detroit Dam, therefore, is highly dependent on the location, characteristics, and usage of the dam's outlet structures. Prior to operational changes in 2007, Detroit Dam had a well-documented effect on downstream water temperature that was problematic for endangered salmonid fish species, releasing water that was too cold in midsummer and too warm in autumn. This unnatural seasonal temperature pattern caused problems in the timing of fish migration, spawning, and emergence. In this study, an existing calibrated 2-dimensional hydrodynamic water-quality model [CE-QUAL-W2] of Detroit Lake was used to determine how changes in dam operation or changes to the structural release points of Detroit Dam might affect downstream water temperatures under a range of historical hydrologic and meteorological conditions. The results from a subset of the Detroit Lake model scenarios then were used as forcing conditions for downstream CE-QUAL-W2 models of Big Cliff Reservoir (the small reregulating reservoir just downstream of Detroit Dam) and the North Santiam and Santiam Rivers. Many combinations of environmental, operational, and

  6. Landslide Inventory for the Little North Santiam River Basin, Oregon

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This geodatabase is an inventory of existing landslides in the Little North Santiam River Basin, Oregon (2009). Each landslide feature shown has been classified...

  7. Simulating potential structural and operational changes for Detroit Dam on the North Santiam River, Oregon, for downstream temperature management

    Science.gov (United States)

    Buccola, Norman L.; Rounds, Stewart A.; Sullivan, Annett B.; Risley, John C.

    2012-01-01

    Detroit Dam was constructed in 1953 on the North Santiam River in western Oregon and resulted in the formation of Detroit Lake. With a full-pool storage volume of 455,100 acre-feet and a dam height of 463 feet, Detroit Lake is one of the largest and most important reservoirs in the Willamette River basin in terms of power generation, recreation, and water storage and releases. The U.S. Army Corps of Engineers operates Detroit Dam as part of a system of 13 reservoirs in the Willamette Project to meet multiple goals, which include flood-damage protection, power generation, downstream navigation, recreation, and irrigation. A distinct cycle in water temperature occurs in Detroit Lake as spring and summer heating through solar radiation creates a warm layer of water near the surface and isolates cold water below. Controlling the temperature of releases from Detroit Dam, therefore, is highly dependent on the location, characteristics, and usage of the dam's outlet structures. Prior to operational changes in 2007, Detroit Dam had a well-documented effect on downstream water temperature that was problematic for endangered salmonid fish species, releasing water that was too cold in midsummer and too warm in autumn. This unnatural seasonal temperature pattern caused problems in the timing of fish migration, spawning, and emergence. In this study, an existing calibrated 2-dimensional hydrodynamic water-quality model [CE-QUAL-W2] of Detroit Lake was used to determine how changes in dam operation or changes to the structural release points of Detroit Dam might affect downstream water temperatures under a range of historical hydrologic and meteorological conditions. The results from a subset of the Detroit Lake model scenarios then were used as forcing conditions for downstream CE-QUAL-W2 models of Big Cliff Reservoir (the small reregulating reservoir just downstream of Detroit Dam) and the North Santiam and Santiam Rivers. Many combinations of environmental, operational, and

  8. Simulating potential structural and operational changes for Detroit Dam on the North Santiam River, Oregon-Interim Results

    Science.gov (United States)

    Buccola, Norman L.; Rounds, Stewart A.

    2011-01-01

    Prior to operational changes in 2007, Detroit Dam on the North Santiam River in western Oregon had a well-documented effect on downstream water temperature that was problematic for endangered salmonid fish species. In this U.S. Geological Survey study, done in cooperation with the U.S. Army Corps of Engineers, an existing calibrated CE-QUAL-W2 model of Detroit Lake (the impounded waterbody behind Detroit Dam) was used to determine how changes in dam operation or changes to the structural release points of Detroit Dam might affect downstream water temperatures under a range of historical hydrologic and meteorological conditions.

  9. Environmental Flow Assessments in the McKenzie and Santiam River Basins, Oregon

    Science.gov (United States)

    Risley, J. C.; Bach, L.; Budai, C.; Duffy, K.

    2012-12-01

    The McKenzie and Santiam Rivers are tributaries of the Willamette River in northwestern Oregon, draining areas of 3,370 and 4,690 square kilometers, respectively. The river basins are heavily forested and contain streams that historically provided critical habit for salmonid rearing, salmonid spawning, and bull trout. In the 1950s and 1960s, hydropower and flood control dams were constructed in both basins. In 2008, the U.S. Geological Survey (USGS), in cooperation with The Nature Conservancy (TNC) and the U.S. Army Corps of Engineers (Corps), began assessing the impacts of dam regulation in the two basins on streamflow, geomorphic, and ecological processes (Risley et. al., 2010; 2012). The baseline assessments were made under the auspices of the Sustainable Rivers Project (SRP), formed in 2002 by TNC and the Corps. SRP is a nation-wide partnership aimed at developing, implementing, and refining environmental flows downstream of dams. Environmental flows can be defined as the streamflow needed to sustain ecosystems while continuing to meet human needs. Determining environmental flows is an iterative collective process involving stakeholders, workshops, bio-monitoring, and follow-up assessments. The dams on the McKenzie and Santiam Rivers have decreased the frequency and magnitude of floods and increased the magnitude of low flows. In the Santiam River study reaches, for example, annual 1-day maximum streamflows decreased by 46-percent on average because of regulated streamflow conditions. Annual 7-day minimum flows in six of the seven study reaches increased by 146 percent on average. On a seasonal basis, median monthly streamflows in both river basins decreased from February to May and increased from September to January. However, the magnitude of these impacts usually decreased farther downstream from the dams because of the cumulative inflow from unregulated tributaries and groundwater discharge below the dams. In addition to streamflow assessments, the USGS

  10. Location of Photographs Showing Landslide Features in the Little North Santiam River Basin, Oregon

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Data points represent locations of photographs taken of landslides in the Little North Santiam River Basin, Oregon. Photos were taken in spring of 2010 during field...

  11. Timber Harvest Change in the Little North Santiam River Basin, Oregon, 1995 to 2009

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Using available aerial photos from approximately a 15-year period, changes in timber harvest were mapped in the Little North Santiam River Basin, Oregon. Timber...

  12. Landslide Deposit Boundaries for the Little North Santiam River Basin, Oregon

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This layer is an inventory of existing landslides deposits in the Little North Santiam River Basin, Oregon (2009). Each landslide deposit shown on this map has been...

  13. Head Scarp Boundary for the Landslides in the Little North Santiam River Basin, Oregon

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Polygons represent head scarps and flank scarps associated with landslide deposits in the Little North Santiam River Basin, Oregon. This work was completed as part...

  14. Results of temperature gradient and heat flow in Santiam Pass Area, Oregon, Volume 1

    Energy Technology Data Exchange (ETDEWEB)

    Cox, B.L.; Gardner, M.C.; Koenig, J.B.

    1981-08-01

    The conclusions of this report are: (1) There is a weakly defined thermal anomaly within the area examined by temperature-gradient holes in the Santiam Pass area. This is a relict anomaly showing differences in permeability between the High Cascades and Western Cascades areas, more than a fundamental difference in shallow crustal temperatures. (2) The anomaly as defined by the 60 F isotherms at 400 feet follows a north-south trend immediately westward of the Cascade axis in the boundary region. It is clear that all holes spudded into High Cascades rocks result in isothermal and reversal gradients. Holes spudded in Western Cascades rocks result in positive gradients. (3) Cold groundwater flow influences and masks temperature gradients in the High Cascades to a depth of at least 700 feet, especially eastward from the major north-south trending faults. Pleistocene and Holocene rocks are very permeable aquifers. (4) Shallow gradient drilling in the lowlands westward of the faults provides more interpretable information than shallow drilling in the cold-water recharge zones. Topographic and climatological effects can be filtered out of the temperature gradient results. (5) The thermal anomaly seems to have 2 centers: one in the Belknap-Foley area, and one northward in the Sand Mountain area. The anomalies may or may not be connected along a north-south trend. (6) A geothermal effect is seen in holes downslope of the Western-High Cascade boundary. Mixing with cold waters is a powerful influence on temperature gradient data. (7) The temperature-gradient program has not yet examined and defined the geothermal resources potential of the area eastward of the Western Cascades-High Cascades boundary. Holes to 1500-2000 feet in depth are required to penetrate the high permeability-cold groundwater regime. (8) Drilling conditions are unfavorable. There are very few accessible level drill sites. Seasonal access problems and environmental restrictions together with frequent lost

  15. Top of Head Scarp and Internal Scarps for Landslide Deposits in the Little North Santiam River Basin, Oregon

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Data points represent head scarps, flank scarps, and minor internal scarps (linear) associated with landslide deposits in the Little North Santiam River Basin,...

  16. Geology and geothermal resources of the Santiam Pass area of the Oregon Cascade Range, Deschutes, Jefferson and Linn Counties, Oregon

    Energy Technology Data Exchange (ETDEWEB)

    Hill, B.E. (ed.)

    1992-10-01

    This open-file report presents the results of the Santiam Pass drilling program. The first phase of this program was to compile all available geological, geophysical and geothermal data for the Santiam Pass area and select a drill site on the basis of these data (see Priest and others, 1987a), A summary of the drilling operations and costs associated with the project are presented in chapter 1 by Hill and Benoit. An Overview of the geology of the Santiam Pass area is presented by Hill and Priest in chapter 2. Geologic mapping and isotopic age determinations in the Santiam Pass-Mount Jefferson area completed since 1987 are summarized in chapter 2. One of the more important conclusions reached in chapter 2 is that a minimum of 2 km vertical displacement has occurred in the High Cascade graben in the Santiam Pass area. The petrology of the Santiam Pass drill core is presented by Hill in chapter 3. Most of the major volcanic units in the core have been analyzed for major, minor, and trace element abundances and have been studied petrographically. Three K-Ar ages are interpreted in conjunction with the magnetostratigraphy of the core to show that the oldest rocks in the core are approximately 1.8 Ma. Geothermal and geophysical data collected from the Santiam Pass well are presented by Blackwell in chapter 4. The Santiam Pass well failed to penetrate beneath the zone of lateral groundwater flow associated with highly permeable Quaternary volcanic rocks. Calculated geothermal gradients range from about 50[degree]C/km at depth 700-900 m, to roughly 110[degree]C/km from 900 m to the bottom of the well at 929 m. Heat-flow values for the bottom part of the hole bracket the regional average for the High Cascades. Blackwell concludes that heat flow along the High Cascades axis is equal to or higher than along the western edge of the High Cascades.

  17. Development of CE-QUAL-W2 models for the Middle Fork Willamette and South Santiam Rivers, Oregon

    Science.gov (United States)

    Buccola, Norman L.; Stonewall, Adam J.; Sullivan, Annett B.; Kim, Yoonhee; Rounds, Stewart A.

    2013-01-01

    Hydrodynamic (CE-QUAL-W2) models of Hills Creek Lake (HCL), Lookout Point Lake (LOP), and Dexter Lake (DEX) on the Middle Fork Willamette River (MFWR), and models of Green Peter Lake and Foster Lake on the South Santiam River systems in western Oregon were updated and recalibrated for a wide range of flow and meteorological conditions. These CE-QUAL-W2 models originally were developed by West Consultants, Inc., for the U.S. Army Corps of Engineers. This study by the U.S. Geological Survey included a reassessment of the models’ calibration in more recent years—2002, 2006, 2008, and 2011—categorized respectively as low, normal, high, and extremely high flow calendar years. These years incorporated current dam-operation practices and more available data than the time period used in the original calibration. Modeled water temperatures downstream of both HCL and LOP-DEX on the MFWR were within an average of 0.68 degree Celsius (°C) of measured values; modeled temperatures downstream of Foster Dam on the South Santiam River were within an average of 0.65°C of measured values. A new CE-QUAL-W2 model was developed and calibrated for the riverine MFWR reach between Hills Creek Dam and the head of LOP, allowing an evaluation of the flow and temperature conditions in the entire MFWR system from HCL to Dexter Dam. The complex bathymetry and long residence time of HCL, combined with the relatively deep location of the power and regulating outlet structures at Hills Creek Dam, led to a HCL model that was highly sensitive to several outlet and geometric parameters related to dam structures (STR TOP, STR BOT, STR WIDTH). Release temperatures from HCL were important and often persisted downstream as they were incorporated in the MFWR model and the LOP-DEX model (downstream of MFWR). The models tended to underpredict the measured temperature of water releases from Dexter Dam during the late-September-through-December drawdown period in 2002, and again (to a lesser extent) in

  18. Geology and geothermal resources of the Santiam Pass area of the Oregon Cascade Range, Deschutes, Jefferson and Linn Counties, Oregon. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Hill, B.E. [ed.

    1992-10-01

    This open-file report presents the results of the Santiam Pass drilling program. The first phase of this program was to compile all available geological, geophysical and geothermal data for the Santiam Pass area and select a drill site on the basis of these data (see Priest and others, 1987a), A summary of the drilling operations and costs associated with the project are presented in chapter 1 by Hill and Benoit. An Overview of the geology of the Santiam Pass area is presented by Hill and Priest in chapter 2. Geologic mapping and isotopic age determinations in the Santiam Pass-Mount Jefferson area completed since 1987 are summarized in chapter 2. One of the more important conclusions reached in chapter 2 is that a minimum of 2 km vertical displacement has occurred in the High Cascade graben in the Santiam Pass area. The petrology of the Santiam Pass drill core is presented by Hill in chapter 3. Most of the major volcanic units in the core have been analyzed for major, minor, and trace element abundances and have been studied petrographically. Three K-Ar ages are interpreted in conjunction with the magnetostratigraphy of the core to show that the oldest rocks in the core are approximately 1.8 Ma. Geothermal and geophysical data collected from the Santiam Pass well are presented by Blackwell in chapter 4. The Santiam Pass well failed to penetrate beneath the zone of lateral groundwater flow associated with highly permeable Quaternary volcanic rocks. Calculated geothermal gradients range from about 50{degree}C/km at depth 700-900 m, to roughly 110{degree}C/km from 900 m to the bottom of the well at 929 m. Heat-flow values for the bottom part of the hole bracket the regional average for the High Cascades. Blackwell concludes that heat flow along the High Cascades axis is equal to or higher than along the western edge of the High Cascades.

  19. Water Pollution Control Industry

    Science.gov (United States)

    Environmental Science and Technology, 1974

    1974-01-01

    A special report on the state of the water pollution control industry reveals that due to forthcoming federal requirements, sales and the backlogs should increase; problems may ensue because of shortages of materials and inflation. Included are reports from various individual companies. (MLB)

  20. Water Pollution Control Industry

    Science.gov (United States)

    Environmental Science and Technology, 1974

    1974-01-01

    A special report on the state of the water pollution control industry reveals that due to forthcoming federal requirements, sales and the backlogs should increase; problems may ensue because of shortages of materials and inflation. Included are reports from various individual companies. (MLB)

  1. Hydrography - Water Pollution Control Facilities

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — A Water Pollution Control Facility is a DEP primary facility type related to the Water Pollution Control Program. The sub-facility types related to Water Pollution...

  2. Wildlife and Wildlife Habitat Loss Assessment at Green Peter-Foster Project; Middle Fork Santiam River, Oregon, 1985 Final Report.

    Energy Technology Data Exchange (ETDEWEB)

    Noyes, J.H.

    1986-02-01

    A habitat based assessment was conducted of the US Army Corps of Engineers' Green Peter-Foster Dam and Reservoir Project on the Middle Fork Santiam River, Oregon, to determine losses or gains resulting from the development and operation of the hydroelectric related components of the project. Preconstruction, postconstruction, and recent vegetation cover types at the project site were mapped based on aerial photographs from 1955, 1972, and 1979, respectively. Vegetation cover types were identified within the affected area and acreages of each type at each period were determined. Eleven wildlife target species were selected to represent a cross-section of species groups affected by the project. An interagency team evaluated the suitability of the habitat to support the target species at each time period. An evaluation procedure which accounted for both the quantity and quality of habitat was used to aid in assessing impacts resulting from the project. The Green Peter-Foster Project extensively altered or affected 7873 acres of land and river in the Santiam River drainage. Impacts to wildlife centered around the loss of 1429 acres of grass-forb vegetation, 768 acres of shrubland, and 717 acres of open conifer forest cover types. Impacts resulting from the Green Peter-Foster Project included the loss of critical winter range for black-tailed deer and Roosevelt elk, and the loss of year-round habitat for deer, upland game birds, river otter, beaver, pileated woodpecker, and many other wildlife species. Bald eagle and osprey were benefited by an increase in foraging habitat. The potential of the affected area to support wildlife was greatly altered as a result of the Green Peter-Foster Project. Losses or gains in the potential of the habitat to support wildlife will exist over the life of the project.

  3. Environmental Monitoring, Water Quality - Water Pollution Control Facilities

    Data.gov (United States)

    NSGIC Education | GIS Inventory — A Water Pollution Control Facility is a DEP primary facility type related to the Water Pollution Control Program. The sub-facility types related to Water Pollution...

  4. Careers in Water Pollution Control.

    Science.gov (United States)

    Water Pollution Control Federation, Washington, DC.

    Described are the activities, responsibilities, and educational and training requirements of the major occupations directly concerned with water pollution control. Also provided is an overview of employment trends, salaries, and projected demand for employees. Included in the appendix is a list of colleges and universities which offer…

  5. Careers in Water Pollution Control.

    Science.gov (United States)

    Water Pollution Control Federation, Washington, DC.

    Described are the activities, responsibilities, and educational and training requirements of the major occupations directly concerned with water pollution control. Also provided is an overview of employment trends, salaries, and projected demand for employees. Included in the appendix is a list of colleges and universities which offer…

  6. Biofouling Control in Cooling Water

    Directory of Open Access Journals (Sweden)

    T. Reg Bott

    2009-01-01

    Full Text Available An important aspect of environmental engineering is the control of greenhouse gas emissions. Fossil fuel-fired power stations, for instance, represent a substantial contribution to this problem. Unless suitable steps are taken the accumulation of microbial deposits (biofouling on the cooling water side of the steam condensers can reduce their efficiency and in consequence, the overall efficiency of power production, with an attendant increase in fuel consumption and hence CO2 production. Biofouling control, therefore, is extremely important and can be exercised by chemical or physical techniques or a combination of both. The paper gives some examples of the effectiveness of different approaches to biofouling control.

  7. Automatic Control of Water Pumping Stations

    Institute of Scientific and Technical Information of China (English)

    Muhannad Alrheeh; JIANG Zhengfeng

    2006-01-01

    Automatic Control of pumps is an interesting proposal to operate water pumping stations among many kinds of water pumping stations according to their functions.In this paper, our pumping station is being used for water supply system. This paper is to introduce the idea of pump controller and the important factors that must be considering when we want to design automatic control system of water pumping stations. Then the automatic control circuit with the function of all components will be introduced.

  8. Controls on open water evaporation

    Directory of Open Access Journals (Sweden)

    R. J. Granger

    2010-05-01

    Full Text Available The paper presents the initial results of a field study of boundary layer behaviour and open water evaporation carried out on two small- to medium-sized lakes in Western and Northern Canada. Meteorological and boundary layer measurements were made over the water surfaces and over the upwind land surface, allowing for an examination of the effect of lake-land contrasts of temperature on the wind speed over the open water and on the evaporation rates. Lake evaporation was measured directly using eddy covariance equipment.

    The study showed that, for time periods shorter than daily, the open water evaporation bears no relationship to the net radiation. The wind speed is the most significant factor governing the evaporation rates, followed by the land-water temperature contrast and the land-water vapour pressure contrast. The effect of the stability on the wind field is demonstrated; stability over the water and adjacent land surfaces are, for the most part, out of phase. The derived relationships will be used to develop a model for estimating the hourly evaporation rates from open water.

    Examination of the seasonal trends shows that the open water period can be separated into two distinct evaporative regimes: the warming period in the Spring, when the land temperature is greater than the water temperature, the turbulent fluxes over water are suppressed; and the cooling period, when the water temperature is greater than the air temperature, and the turbulent fluxes over water are enhanced.

  9. Wildlife and Wildlife Habitat Loss Assessment at Detroit Big Cliff Dam and Reservoir Project, North Santiam River, Oregon, 1985 Final Report.

    Energy Technology Data Exchange (ETDEWEB)

    Noyes, J.H.

    1985-02-01

    A habitat based assessment was conducted of the US Army Corps of Engineers' Detroit/Big Cliff Dam and Reservoir Project (Detroit Project) on the North Santiam River, Oregon, to determine losses or gains resulting from the development and operation of the hydroelectric-related components of the project. Preconstruction, postconstruction, and recent vegetation cover types at the project site were mapped based on aerial photographs from 1939, 1956, and 1979, respectively. Vegetation cover types were identified within the affected area and acreages of each type at each time period were determined. Ten wildlife target species were selected to represent a cross-section of species groups affected by the project. An interagency team evaluated the suitability of the habitat to support the target species at each time period. An evaluation procedure which accounted for both the quantity and quality of habitat was used to aid in assessing impacts resulting from the project. The Detroit Project extensively altered or affected 6324 acres of land and river in the North Santiam River drainage. Impacts to wildlife centered around the loss of 1,608 acres of conifer forest and 620 acres of riparian habitat. Impacts resulting from the Detroit Project included the loss of winter range for black-tailed deer and Roosevelt elk, and the loss of year-round habitat for deer, river otter, beaver, ruffed grouse, pileated woodpecker, spotted owl, and many other wildlife species. Bald eagle and osprey were benefited by an increase in foraging habitat. The potential of the affected area to support wildlife was greatly altered as a result of the Detroit Project. Losses or gains in the potential of the habitat to support wildlife will exist over the life of the project.

  10. Biology and Water Pollution Control.

    Science.gov (United States)

    Warren, Charles E.

    Within this text, the reader is attuned to the role biology can and should play in combating the alarming increase in water pollution. Both the urgency of the problem and the biological techniques that are being developed to cope with the water pollution crisis are scrutinized; what is and is not known about the problem is explained; past,…

  11. Biology and Water Pollution Control.

    Science.gov (United States)

    Warren, Charles E.

    Within this text, the reader is attuned to the role biology can and should play in combating the alarming increase in water pollution. Both the urgency of the problem and the biological techniques that are being developed to cope with the water pollution crisis are scrutinized; what is and is not known about the problem is explained; past,…

  12. Combined air and water pollution control system

    Science.gov (United States)

    Wolverton, Billy C. (Inventor); Jarrell, Lamont (Inventor)

    1990-01-01

    A bioaquatic air pollution control system for controlling both water and atmospheric pollution is disclosed. The pollution control system includes an exhaust for directing polluted gases out of a furnace and a fluid circulating system which circulates fluid, such as waste water, from a source, past the furnace where the fluid flow entrains the pollutants from the furnace. The combined fluid and pollutants are then directed through a rock/plant/microbial filtering system. A suction pump pumps the treated waste water from the filter system past the exhaust to again entrain more pollutants from the furnace where they are combined with the fluid (waste water) and directed to the filter system.

  13. Development of Mechanical Water Level Controller

    OpenAIRE

    Akonyi Nasiru Sule; Chinedu Cletus Obinwa; Christian Ebele Okekeze; Eyo Ifreke

    2012-01-01

    The automatic water level controller is a device designed to regulate automatically the pumping of water to an overhead tank without allowing the water in the tank to be exhausted. The design of this mechanical device was achieved using the Archimedes principle of floatation; having a float which determines the water level in the tank depending on the choice of the minimum (lower) and maximum (upper) level inscribed in the tank. The fundamental attribute of this device is the ease in design, ...

  14. Water-controlled wealth of nations

    OpenAIRE

    2013-01-01

    Population growth is in general constrained by food production, which in turn depends on the access to water resources. At a country level, some populations use more water than they control because of their ability to import food and the virtual water required for its production. Here, we investigate the dependence of demographic growth on available water resources for exporting and importing nations. By quantifying the carrying capacity of nations on the basis of calculations of the virtual ...

  15. Review of water pollution control in China

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Water resource shortage and pollution has seriously threatened the survival and development of developing countries.Because of China's specific economical and social circumstances,complete adoption of developed countries' experience is unrealistic.At present,China needs to develop strategies and technologies in source water pollution control and municipal environmental remediation that embrace the country's specific need to battle the water resource problem.Among them,efficient source water pretreatment is a critical step to ensure a safe municipal water supply.Unlike developed countries,it is not yet feasible in China to treat water supplied to the household and have it meet the standard of direct drinking;therefore,it is more appropriate to refer to it as service water.As a beneficial supplement,an additional community drinking water network and household drinking water apparatus can be considered.

  16. Virtual water controlled demographic growth of nations

    CERN Document Server

    Suweis, Samir; Maritan, Amos; D'Odorico, Paolo

    2013-01-01

    Population growth is in general constrained by food production, which in turn depends on the access to water resources. At a country level, some populations use more water than they control because of their ability to import food and the virtual water required for its production. Here, we investigate the dependence of demographic growth on available water resources for exporting and importing nations. By quantifying the carrying capacity of nations based on calculations of the virtual water available through the food trade network, we point to the existence of a global water unbalance. We suggest that current export rates will not be maintained and consequently we question the long-run sustainability of the food trade system as a whole. Water rich regions are likely to soon reduce the amount of virtual water they export, thus leaving import-dependent regions without enough water to sustain their populations. We also investigate the potential impact of possible scenarios that might mitigate these effects throu...

  17. MPC control of water supply networks

    DEFF Research Database (Denmark)

    Baunsgaard, Kenneth Marx Hoe; Ravn, Ole; Kallesoe, Carsten Skovmose;

    2016-01-01

    This paper investigates the modelling and predictive control of a drinking water supply network with the aim of minimising the energy and economic cost. A model predictive controller, MPC, is applied to a nonlinear model of a drinking water network that follows certain constraints to maintain...... consumer pressure desire. A model predictive controller, MPC, is based on a simple model that models the main characteristics of a water distribution network, optimizes a desired cost minimisation, and keeps the system inside specified constraints. In comparison to a logic (on/off) control design......, controlling the drinking water supply network with the MPC showed reduction of the energy and the economic cost of running the system. This has been achieved by minimising actuator control effort and by shifting the actuator use towards the night time, where energy prices are lower. Along with energy cost...

  18. Water-controlled wealth of nations.

    Science.gov (United States)

    Suweis, Samir; Rinaldo, Andrea; Maritan, Amos; D'Odorico, Paolo

    2013-03-12

    Population growth is in general constrained by food production, which in turn depends on the access to water resources. At a country level, some populations use more water than they control because of their ability to import food and the virtual water required for its production. Here, we investigate the dependence of demographic growth on available water resources for exporting and importing nations. By quantifying the carrying capacity of nations on the basis of calculations of the virtual water available through the food trade network, we point to the existence of a global water unbalance. We suggest that current export rates will not be maintained and consequently we question the long-term sustainability of the food trade system as a whole. Water-rich regions are likely to soon reduce the amount of virtual water they export, thus leaving import-dependent regions without enough water to sustain their populations. We also investigate the potential impact of possible scenarios that might mitigate these effects through (i) cooperative interactions among nations whereby water-rich countries maintain a tiny fraction of their food production available for export, (ii) changes in consumption patterns, and (iii) a positive feedback between demographic growth and technological innovations. We find that these strategies may indeed reduce the vulnerability of water-controlled societies.

  19. Development of Mechanical Water Level Controller

    Directory of Open Access Journals (Sweden)

    Akonyi Nasiru Sule

    2012-10-01

    Full Text Available The automatic water level controller is a device designed to regulate automatically the pumping of water to an overhead tank without allowing the water in the tank to be exhausted. The design of this mechanical device was achieved using the Archimedes principle of floatation; having a float which determines the water level in the tank depending on the choice of the minimum (lower and maximum (upper level inscribed in the tank. The fundamental attribute of this device is the ease in design, fabrication and mounting at a lower cost. Its testing had shown and proved that it works efficiently with Archimedes’ principle of floatation. This eliminates the frequent human intervention/monitoring of the water level in the overhead tank to control overflow manually, thereby eliminating water and energy wastages.

  20. Tingzikou key water control project started construction

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Tingzikou key water control project on Jialing River, one of 18 newly started key projects in 2009 for China's western part development program, formally started construction at the end of November last year.

  1. Residuals Management and Water Pollution Control Planning.

    Science.gov (United States)

    Environmental Protection Agency, Washington, DC. Office of Public Affairs.

    This pamphlet addresses the problems associated with residuals and water quality especially as it relates to the National Water Pollution Control Program. The types of residuals and appropriate management systems are discussed. Additionally, one section is devoted to the role of citizen participation in developing management programs. (CS)

  2. Residuals Management and Water Pollution Control Planning.

    Science.gov (United States)

    Environmental Protection Agency, Washington, DC. Office of Public Affairs.

    This pamphlet addresses the problems associated with residuals and water quality especially as it relates to the National Water Pollution Control Program. The types of residuals and appropriate management systems are discussed. Additionally, one section is devoted to the role of citizen participation in developing management programs. (CS)

  3. Human right to water and conventionality control

    Directory of Open Access Journals (Sweden)

    Adriana N. Martínez

    2013-12-01

    Full Text Available Humanity faces the challenge of achieving the sustainability of water resources supply for the satisfaction of human needs and ofensuring the sustainability of the natural ecosystems for the achievement of sustainable human development and the quality of life of present and future generations. For this reason the recognition of access to water as a Human Right has fundamental significance. We proceed to analyze the international instruments that provide content and legal basis to the human right to water and the obligations of States. In this context, we deal with the constitutional reception of human right to water in Argentina in the constitutional reform of 1994 and the control of conventionality as guarantor of access to water, which has led to different domestic courts to consider cases in which a violation ofthe right to water was proved.

  4. Public Information for Water Pollution Control.

    Science.gov (United States)

    Water Pollution Control Federation, Washington, DC.

    This publication is a handbook for water pollution control personnel to guide them towards a successful public relations program. This handbook was written to incorporate the latest methods of teaching basic public information techniques to the non-professional in this area. Contents include: (1) a rationale for a public information program; (2)…

  5. Water Pollution Control Across the Nation

    Science.gov (United States)

    Environmental Science and Technology, 1973

    1973-01-01

    Reviewed are accomplishments, problems, and frustrations faced by individual states in meeting requirements of P.L. 92-500, Federal Water Pollution Control Act Amendments of 1972. State Environmental officials complain the new law may be a hindrance to established cleanup programs. Statistics and charts are given. (BL)

  6. Public Information for Water Pollution Control.

    Science.gov (United States)

    Water Pollution Control Federation, Washington, DC.

    This publication is a handbook for water pollution control personnel to guide them towards a successful public relations program. This handbook was written to incorporate the latest methods of teaching basic public information techniques to the non-professional in this area. Contents include: (1) a rationale for a public information program; (2)…

  7. Water Pollution Control Across the Nation

    Science.gov (United States)

    Environmental Science and Technology, 1973

    1973-01-01

    Reviewed are accomplishments, problems, and frustrations faced by individual states in meeting requirements of P.L. 92-500, Federal Water Pollution Control Act Amendments of 1972. State Environmental officials complain the new law may be a hindrance to established cleanup programs. Statistics and charts are given. (BL)

  8. On fuzzy control of water desalination plants

    Energy Technology Data Exchange (ETDEWEB)

    Titli, A. [Centre National de la Recherche Scientifique (CNRS), 31 - Toulouse (France); Jamshidi, M. [New Mexico Univ., Albuquerque, NM (United States); Olafsson, F. [Institute of Technology, Norway (Norway)

    1995-12-31

    In this report we have chosen a sub-system of an MSF water desalination plant, the brine heater, for analysis, synthesis, and simulation. This system has been modelled and implemented on computer. A fuzzy logic controller (FLC) for the top brine temperature control loop has been designed and implemented on the computer. The performance of the proposed FLC is compared with three other conventional control strategies: PID, cascade and disturbance rejection control. One major concern on FLC`s has been the lack of stability criteria. An up to-date survey of stability of fuzzy control systems is given. We have shown stability of the proposed FLC using the Sinusoidal Input Describing Functions (SIDF) method. The potential applications of fuzzy controllers for complex and large-scale systems through hierarchy of rule sets and hybridization with conventional approaches are also investigated. (authors)

  9. Cavity filling water control below aerator devices

    Institute of Scientific and Technical Information of China (English)

    钱尚拓; 吴建华; 马飞; 徐建荣; 彭育; 汪振

    2014-01-01

    With the rapid development of high dam projects within China, the dragon-drop-tail spillway tunnel is introduced and widely used. In view of the high water head and the large flow velocity on the dragon-drop-tail section, aerator devices are usually placed for the cavitation damage control. For the device placed in its initial position, it is a serious concern to design a suitable flow regime of the cavity and to control the cavity filling water due to the large flow depth and the low Froude number through this aera-tor. In this study, the relationships between the geometries of the aerator device and the jet impact angle of the lower trajectory of the flow are theoretically analyzed with/without a local slope. Nine test cases with different geometries are designed, the effectiveness of the filling water control is experimentally investigated under different operation conditions, and two criteria of the local slope design are proposed. It is concluded that the cavity flow regime and the filling water can be improved if a small impact angle and some sui-table geometries of the local slope are designed.

  10. Separation control with fluidic oscillators in water

    Science.gov (United States)

    Schmidt, H.-J.; Woszidlo, R.; Nayeri, C. N.; Paschereit, C. O.

    2017-08-01

    The present study assesses the applicability of fluidic oscillators for separation control in water. The first part of this work evaluates the properties of the fluidic oscillators including frequency, cavitation effects, and exerted thrust. Derived from the governing internal dynamics, the oscillation frequency is found to scale directly with the jet's exit velocity and the size of the fluidic oscillator independent of the working fluid. Frequency data from various experiments collapse onto a single curve. The occurrence of cavitation is examined by visual inspection and hydrophone measurements. The oscillation frequency is not affected by cavitation because it does not occur inside the oscillators. The spectral information obtained with the hydrophone provide a reliable indicator for the onset of cavitation at the exit. The performance of the fluidic oscillators for separation control on a bluff body does not seem to be affected by the presence of cavitation. The thrust exerted by an array of fluidic oscillators with water as the working fluid is measured to be even larger than theoretically estimated values. The second part of the presented work compares the performance of fluidic oscillators for separation control in water with previous results in air. The array of fluidic oscillators is installed into the rear end of a bluff body model. The drag improvements based on force balance measurements agree well with previous wind tunnel experiments on the same model. The flow field is examined by pressure measurements and with particle image velocimetry. Similar performance and flow field characteristics are observed in both water and air.

  11. Adaptive Control and Synchronization of the Shallow Water Model

    Directory of Open Access Journals (Sweden)

    P. Sangapate

    2012-01-01

    Full Text Available The shallow water model is one of the important models in dynamical systems. This paper investigates the adaptive chaos control and synchronization of the shallow water model. First, adaptive control laws are designed to stabilize the shallow water model. Then adaptive control laws are derived to chaos synchronization of the shallow water model. The sufficient conditions for the adaptive control and synchronization have been analyzed theoretically, and the results are proved using a Barbalat's Lemma.

  12. Advanced control of a water supply system: a case study

    NARCIS (Netherlands)

    Bakker, M.; Rajewicz, T.; Kien, H.; Vreeburg, J.H.G.; Rietveld, L.C.

    2014-01-01

    Conventional automatic production flow control and pump pressure control of water supply systems are robust and simple: production flow is controlled based on the level in the clear water reservoir and pump pressure is controlled on a static set-point. Recently, more advanced computer-based control

  13. Artesian water supply control system in transient conditions

    Directory of Open Access Journals (Sweden)

    Костянтин Олегович Буравченко

    2016-06-01

    Full Text Available The paper describes an artesian water supply control system in the transition mode. The control system searches for the optimal performance trajectory of the water supply on the basis of a maximum return with a view to the fastest mode of stabilization. The analysis of artesian water supply control systems in transition mode and methods of improvement was conducted

  14. An efficient water flow control approach for water heaters in direct load control

    NARCIS (Netherlands)

    Belov, Alexander; Meratnia, Nirvana; Zwaag, van der Berend Jan; Havinga, Paul

    2014-01-01

    Tank water heaters (WHs) are present in a prevailing number of European households. Serving as energy buffers WHs have come under the spotlight of various direct load control (DLC) programs over the last few decades. Although DLC has proven to be an efficient measure towards daily peak demand shavin

  15. An interdisciplinary approach to valuing water from brush control

    OpenAIRE

    Lemberg, B.; Mjelde, J.; Conner, J; Griffin, R.; Rosenthal, W; Stuth, J

    2002-01-01

    Metadata only record This paper develops an integrated model to assess the viability of increasing water yields in the Frio River basin of Texas through brush control. The presented method accounts for the effect of brush control on forage productivity and water supply by incorporating ecological, hydrologic, and economic models. The simulation of water yields suggests that brush control would increase water yields on 35% of the land area, but the costs usually would exceed the financial b...

  16. Contamination Control and Monitoring of Tap Water as Fluid in Industrial Tap Water Hydraulic Systems

    DEFF Research Database (Denmark)

    Conrad, Finn; Adelstorp, Anders

    1998-01-01

    Presentation of results and methods addressed to contamination control and monitoring of tap water as fluid in tap water hydraulic systems.......Presentation of results and methods addressed to contamination control and monitoring of tap water as fluid in tap water hydraulic systems....

  17. Contamination Control and Monitoring of Tap Water as Fluid in Industrial Tap Water Hydraulic Systems

    DEFF Research Database (Denmark)

    Conrad, Finn; Adelstorp, Anders

    1998-01-01

    Presentation of results and methods addressed to contamination control and monitoring of tap water as fluid in tap water hydraulic systems.......Presentation of results and methods addressed to contamination control and monitoring of tap water as fluid in tap water hydraulic systems....

  18. Artificial Intelligence Based Alum Dosage Control in Water Treatment Plant

    Directory of Open Access Journals (Sweden)

    P Poongodi

    2013-08-01

    Full Text Available Supplying good quality of drinking water is a challenging task during the rainy season and floods. During this period water becomes highly polluted with suspended solids which increase the water turbidity. Alum is used to reduce the turbidity of the water. Typically in water treatment plants alum dosage is decided by the Jar test and the desired alum dosage is added manually. This research proposes an automatic alum dosage mixing process. The alum dosage is controlled by an intelligent controller which consists of a dosage predictor, an inverse model of the dosage pump and a Pulse Width Modulation (PWM controller. The optimal alum dosage is predicted by the dosage predictor. The PWM controller controls the flow rate of the alum dosing pump. This proposed method has been implemented in a laboratory based water treatment plant and it ensures the automation in water treatment plant to supply good quality drinking water.

  19. Aquatic weed control within an integrated water management framework.

    NARCIS (Netherlands)

    Querner, E.P.

    1993-01-01

    Aquatic weed control, carried out by the water boards in the Netherlands, is required to maintain sufficient discharge capacity of the surface water system. Weed control affects the conditions of both surface water and groundwater. The physically based model MOGROW was developed to simulate the flow

  20. Model predictive control on open water systems

    NARCIS (Netherlands)

    Van Overloop, P.J.

    2006-01-01

    Human life depends on water daily, especially for drinking and food production. Also, human life needs to be protected against excess of water caused by heavy precipitation and floods. People have formed water management organizations to guarantee these necessities of life for communities. These org

  1. Following the water: a controlled study of drinking water storage in northern coastal Ecuador.

    Science.gov (United States)

    Levy, Karen; Nelson, Kara L; Hubbard, Alan; Eisenberg, Joseph N S

    2008-11-01

    To design the most appropriate interventions to improve water quality and supply, information is needed to assess water contamination in a variety of community settings, including those that rely primarily on unimproved surface sources of drinking water. We explored the role of initial source water conditions as well as household factors in determining household water quality, and how levels of contamination of drinking water change over time, in a rural setting in northern coastal Ecuador. We sampled source waters concurrently with water collection by household members and followed this water over time, comparing Escherichia coli and enterococci concentrations in water stored in households with water stored under controlled conditions. We observed significant natural attenuation of indicator organisms in control containers and significant, although less pronounced, reductions of indicators between the source of drinking water and its point of use through the third day of sampling. These reductions were followed by recontamination in approximately half of the households. Water quality improved after water was transferred from the source to household storage containers, but then declined because of recontamination in the home. Our experimental design allowed us to observe these dynamics by controlling for initial source water quality and following changes in water quality over time. These data, because of our controlled experimental design, may explain why recontamination has been reported in the literature as less prominent in areas or households with highly contaminated source waters. Our results also suggest that efforts to improve source water quality and sanitation remain important.

  2. Economics of selected water control technologies and their ...

    African Journals Online (AJOL)

    Economics of selected water control technologies and their successful use: The case of Ethiopia. ... of these controls technologies and institutionalizing some sort of cost recovery schemes. ... DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT.

  3. Modeling Hydrodynamics, Water Temperature, and Suspended Sediment in Detroit Lake, Oregon

    Science.gov (United States)

    Sullivan, Annett B.; Rounds, Stewart A.; Sobieszczyk, Steven; Bragg, Heather M.

    2007-01-01

    Detroit Lake is a large reservoir on the North Santiam River in west-central Oregon. Water temperature and suspended sediment are issues of concern in the river downstream of the reservoir. A CE-QUAL-W2 model was constructed to simulate hydrodynamics, water temperature, total dissolved solids, and suspended sediment in Detroit Lake. The model was calibrated for calendar years 2002 and 2003, and for a period of storm runoff from December 1, 2005, to February 1, 2006. Input data included lake bathymetry, meteorology, reservoir outflows, and tributary inflows, water temperatures, total dissolved solids, and suspended sediment concentrations. Two suspended sediment size groups were modeled: one for suspended sand and silt with particle diameters larger than 2 micrometers, and another for suspended clay with particle diameters less than or equal to 2 micrometers. The model was calibrated using lake stage data, lake profile data, and data from a continuous water-quality monitor on the North Santiam River near Niagara, about 6 kilometers downstream of Detroit Dam. The calibrated model was used to estimate sediment deposition in the reservoir, examine the sources of suspended sediment exiting the reservoir, and examine the effect of the reservoir on downstream water temperatures.

  4. Invasion and control of water hyacinth (Eichhornia crassipes) in China

    Institute of Scientific and Technical Information of China (English)

    CHU Jian-jun; DING Yi; ZHUANG Qi-jia

    2006-01-01

    By the time of primary 21st century, water hyacinth had become a serious environmental problem in China. Water hyacinth contributes to the major part of ecological hazards from the invasion of foreign plant species, which is estimated about USD 7 billion a year in values.In the past 10 years, herbicides glyphosate, 2,4-D and paraquat have been used in controlling water hyacinth in China. Although the herbicides provided effective control on the weed in some areas, they could not provide the sustainable inhibition on the weed population, while would lead to pollution on water at various levels. At present, the herbicide application on water hyacinth is forbidden in many areas of China such as Shanghai. In this situation, the asexual reproduction inhibitor, KWH02, was invented for controlling water hyacinth and it provided about 70% of growth inhibition without any risk of dead plant pollution.It has been about 10 years for bio-control of water hyacinth in China. Works focused on mainly the efficacy and safety of the utilization of foreign insects. Researches on microorganism herbicides to control water hyacinth were started and obtained primary achievements in recent years.Although there are different opinions on how to face the water hyacinth problem in China, it is accepted widely that the control methods should be high efficient and safe with low cost. Some practical measures for integrated management of water hyacinth are suggested.

  5. Invasion and control of water hyacinth (Eichhornia crassipes) in China.

    Science.gov (United States)

    Chu, Jian-jun; Ding, Yi; Zhuang, Qi-jia

    2006-08-01

    By the time of primary 21st century, water hyacinth had become a serious environmental problem in China. Water hyacinth contributes to the major part of ecological hazards from the invasion of foreign plant species, which is estimated about USD 7 billion a year in values. In the past 10 years, herbicides glyphosate, 2,4-D and paraquat have been used in controlling water hyacinth in China. Although the herbicides provided effective control on the weed in some areas, they could not provide the sustainable inhibition on the weed population, while would lead to pollution of water at various levels. At present, the herbicide application on water hyacinth is forbidden in many areas of China such as Shanghai. In this situation, the asexual reproduction inhibitor, KWH02, was invented for controlling water hyacinth and it provided about 70% of growth inhibition without any risk of dead plant pollution. It has been about 10 years for bio-control of water hyacinth in China. Works focused on mainly the efficacy and safety of the utilization of foreign insects. Researches on microorganism herbicides to control water hyacinth were started and obtained primary achievements in recent years. Although there are different opinion on how to face the water hyacinth problem in China, it is accepted widely that the control methods should be high efficient and safe with low cost. Some practical measures for integrated management of water hyacinth are suggested.

  6. Overview on Treatment and Control Technology for Water Eutrophication

    Institute of Scientific and Technical Information of China (English)

    Anfeng; LI; Tao; PAN; Chong; YANG; Xiang; HU; Jianping; LIU; Chengxi; WU

    2013-01-01

    Eutrophication is one of the important reasons for water pollution and is also the problem for water pollution treatment at home and abroad. This article takes an overview on various technical methods and their characteristics applicable for treatment and control of water eutrophication from the aspects of physics, chemistry, biochemistry and environmental factors regulation, and discusses the application and development trend for relevant technologies.

  7. Controlling water evaporation through self-assembly.

    Science.gov (United States)

    Roger, Kevin; Liebi, Marianne; Heimdal, Jimmy; Pham, Quoc Dat; Sparr, Emma

    2016-09-13

    Water evaporation concerns all land-living organisms, as ambient air is dryer than their corresponding equilibrium humidity. Contrarily to plants, mammals are covered with a skin that not only hinders evaporation but also maintains its rate at a nearly constant value, independently of air humidity. Here, we show that simple amphiphiles/water systems reproduce this behavior, which suggests a common underlying mechanism originating from responding self-assembly structures. The composition and structure gradients arising from the evaporation process were characterized using optical microscopy, infrared microscopy, and small-angle X-ray scattering. We observed a thin and dry outer phase that responds to changes in air humidity by increasing its thickness as the air becomes dryer, which decreases its permeability to water, thus counterbalancing the increase in the evaporation driving force. This thin and dry outer phase therefore shields the systems from humidity variations. Such a feedback loop achieves a homeostatic regulation of water evaporation.

  8. CONTROL OF ZOONOTIC DISEASES IN DRINKING WATER

    Science.gov (United States)

    For over a century, the process of providing hygienically safe drinking water has focused on utilizing treatment processes to provide barriers to the passage of infectious disease-causing organisms to humans. This concept is often considered the cornerstone of sanitary engineerin...

  9. Robust Control of Urban Industrial Water Mismatching Uncertain System

    Directory of Open Access Journals (Sweden)

    LI Kebai

    2013-02-01

    Full Text Available Urban industrial water system parameter fluctuation producing uncertainty may not occur in a control input channel, can be applied mismatching uncertain system to describe. Based on Lyapunov direct method and linear matrix inequality, design the urban industrial water mismatching uncertain system feedback stabilization robust control scheme. Avoid the defects that the feedback stabilization control method based on the matrix Riccati equation need to preset equation parameters, easier to solve and can reduce the conservative.

  10. Grouting Control for Deep-Water Jacket Skirt Pile

    Institute of Scientific and Technical Information of China (English)

    ZHANG Qing; ZHANG Jianxin; XU Lianjiang

    2006-01-01

    Deep-water jacket skirt pile grouting is a critical step in ocean platform construction. Because of the complexity of the skirt pile structure and grouting pipeline, the calculation of grouting pressure and the control of output pressure are involved. Beginning with the jacket skirt pile grouting construction scheme, grouting pressure is estimated on the basis of engineering fluid mechanics theory and variable frequency control technique. Programmable logic controller is the center of grouting pressure control system, which accomplishes the flow control of cement buffer tank water buffer tank, additive buffer tank, cement metering tank, water metering tank, additive metering tank, mixer and agitator. Based on PROFIBUS-DP network, the output pressure of the slurry pump is controlled by the inverter. This method has been applied successfully in JZ20-2 Nor. high spot jacket platform construction.

  11. Radio Frequency Based Water Level Monitor and Controller for ...

    African Journals Online (AJOL)

    Radio Frequency Based Water Level Monitor and Controller for Residential Applications. ... Nigerian Journal of Technology ... This paper elucidates a radio frequency (RF) based transmission and reception system used to remotely monitor ...

  12. A Philosophy of Water Pollution Control--Past and Present.

    Science.gov (United States)

    Schroeffer, George J.

    1978-01-01

    An overview of water pollution control in the U.S. is given, leading to an analysis of present policy trends. A "rational environmental program" is called for to provide economic growth and environmental quality. (MDR)

  13. Recruitment and Employment of the Water Pollution Control Specialist.

    Science.gov (United States)

    Sherrard, J. H.; Sherrard, F. A.

    1979-01-01

    Presented are the basic principles of personnel recruitment and employment for the water pollution control field. Attention is given to determination of staffing requirements, effective planning, labor sources, affirmative action, and staffing policies. (CS)

  14. A Philosophy of Water Pollution Control--Past and Present.

    Science.gov (United States)

    Schroeffer, George J.

    1978-01-01

    An overview of water pollution control in the U.S. is given, leading to an analysis of present policy trends. A "rational environmental program" is called for to provide economic growth and environmental quality. (MDR)

  15. Recruitment and Employment of the Water Pollution Control Specialist.

    Science.gov (United States)

    Sherrard, J. H.; Sherrard, F. A.

    1979-01-01

    Presented are the basic principles of personnel recruitment and employment for the water pollution control field. Attention is given to determination of staffing requirements, effective planning, labor sources, affirmative action, and staffing policies. (CS)

  16. Internal Corrosion Control of Water Supply Systems Code of Practice

    Science.gov (United States)

    This Code of Practice is part of a series of publications by the IWA Specialist Group on Metals and Related Substances in Drinking Water. It complements the following IWA Specialist Group publications: 1. Best Practice Guide on the Control of Lead in Drinking Water 2. Best Prac...

  17. Internal Corrosion Control of Water Supply Systems Code of Practice

    Science.gov (United States)

    This Code of Practice is part of a series of publications by the IWA Specialist Group on Metals and Related Substances in Drinking Water. It complements the following IWA Specialist Group publications: 1. Best Practice Guide on the Control of Lead in Drinking Water 2. Best Prac...

  18. Quadratic controller syntheses for the steam generator water level

    Energy Technology Data Exchange (ETDEWEB)

    Arzelier, D.; Daafouz, J.; Bernussou, J.; Garcia, G

    1998-06-01

    The steam generator water level, (SGWL), control problem in the pressurized water reactor of a nuclear power plant is considered from robust control techniques point of view. The plant is a time-varying system with a non minimum phase behavior and an unstable open-loop response. The time-varying nature of the plant due to change in operating power is taken into account by including slowly time-varying uncertainty in the model. A linear Time-Invariant, (LTI) guaranteed cost quadratic stabilizing controller is designed in order to address some of the particular issues arising for such a control problem. (author) 17 refs.

  19. Modeling, control and optimization of water systems systems engineering methods for control and decision making tasks

    CERN Document Server

    2016-01-01

    This book provides essential background knowledge on the development of model-based real-world solutions in the field of control and decision making for water systems. It presents system engineering methods for modelling surface water and groundwater resources as well as water transportation systems (rivers, channels and pipelines). The models in turn provide information on both the water quantity (flow rates, water levels) of surface water and groundwater and on water quality. In addition, methods for modelling and predicting water demand are described. Sample applications of the models are presented, such as a water allocation decision support system for semi-arid regions, a multiple-criteria control model for run-of-river hydropower plants, and a supply network simulation for public services.

  20. Biological Stability of Drinking Water: Controlling Factors, Methods, and Challenges

    KAUST Repository

    Prest, Emmanuelle I.

    2016-02-01

    Biological stability of drinking water refers to the concept of providing consumers with drinking water of same microbial quality at the tap as produced at the water treatment facility. However, uncontrolled growth of bacteria can occur during distribution in water mains and premise plumbing, and can lead to hygienic (e.g., development of opportunistic pathogens), aesthetic (e.g., deterioration of taste, odor, color) or operational (e.g., fouling or biocorrosion of pipes) problems. Drinking water contains diverse microorganisms competing for limited available nutrients for growth. Bacterial growth and interactions are regulated by factors, such as (i) type and concentration of available organic and inorganic nutrients, (ii) type and concentration of residual disinfectant, (iii) presence of predators, such as protozoa and invertebrates, (iv) environmental conditions, such as water temperature, and (v) spatial location of microorganisms (bulk water, sediment, or biofilm). Water treatment and distribution conditions in water mains and premise plumbing affect each of these factors and shape bacterial community characteristics (abundance, composition, viability) in distribution systems. Improved understanding of bacterial interactions in distribution systems and of environmental conditions impact is needed for better control of bacterial communities during drinking water production and distribution. This article reviews (i) existing knowledge on biological stability controlling factors and (ii) how these factors are affected by drinking water production and distribution conditions. In addition, (iii) the concept of biological stability is discussed in light of experience with well-established and new analytical methods, enabling high throughput analysis and in-depth characterization of bacterial communities in drinking water. We discussed, how knowledge gained from novel techniques will improve design and monitoring of water treatment and distribution systems in order

  1. Biological Stability of Drinking Water: Controlling Factors, Methods, and Challenges

    Science.gov (United States)

    Prest, Emmanuelle I.; Hammes, Frederik; van Loosdrecht, Mark C. M.; Vrouwenvelder, Johannes S.

    2016-01-01

    Biological stability of drinking water refers to the concept of providing consumers with drinking water of same microbial quality at the tap as produced at the water treatment facility. However, uncontrolled growth of bacteria can occur during distribution in water mains and premise plumbing, and can lead to hygienic (e.g., development of opportunistic pathogens), aesthetic (e.g., deterioration of taste, odor, color) or operational (e.g., fouling or biocorrosion of pipes) problems. Drinking water contains diverse microorganisms competing for limited available nutrients for growth. Bacterial growth and interactions are regulated by factors, such as (i) type and concentration of available organic and inorganic nutrients, (ii) type and concentration of residual disinfectant, (iii) presence of predators, such as protozoa and invertebrates, (iv) environmental conditions, such as water temperature, and (v) spatial location of microorganisms (bulk water, sediment, or biofilm). Water treatment and distribution conditions in water mains and premise plumbing affect each of these factors and shape bacterial community characteristics (abundance, composition, viability) in distribution systems. Improved understanding of bacterial interactions in distribution systems and of environmental conditions impact is needed for better control of bacterial communities during drinking water production and distribution. This article reviews (i) existing knowledge on biological stability controlling factors and (ii) how these factors are affected by drinking water production and distribution conditions. In addition, (iii) the concept of biological stability is discussed in light of experience with well-established and new analytical methods, enabling high throughput analysis and in-depth characterization of bacterial communities in drinking water. We discussed, how knowledge gained from novel techniques will improve design and monitoring of water treatment and distribution systems in order

  2. Biological Stability of Drinking Water: Controlling Factors, Methods, and Challenges.

    Science.gov (United States)

    Prest, Emmanuelle I; Hammes, Frederik; van Loosdrecht, Mark C M; Vrouwenvelder, Johannes S

    2016-01-01

    Biological stability of drinking water refers to the concept of providing consumers with drinking water of same microbial quality at the tap as produced at the water treatment facility. However, uncontrolled growth of bacteria can occur during distribution in water mains and premise plumbing, and can lead to hygienic (e.g., development of opportunistic pathogens), aesthetic (e.g., deterioration of taste, odor, color) or operational (e.g., fouling or biocorrosion of pipes) problems. Drinking water contains diverse microorganisms competing for limited available nutrients for growth. Bacterial growth and interactions are regulated by factors, such as (i) type and concentration of available organic and inorganic nutrients, (ii) type and concentration of residual disinfectant, (iii) presence of predators, such as protozoa and invertebrates, (iv) environmental conditions, such as water temperature, and (v) spatial location of microorganisms (bulk water, sediment, or biofilm). Water treatment and distribution conditions in water mains and premise plumbing affect each of these factors and shape bacterial community characteristics (abundance, composition, viability) in distribution systems. Improved understanding of bacterial interactions in distribution systems and of environmental conditions impact is needed for better control of bacterial communities during drinking water production and distribution. This article reviews (i) existing knowledge on biological stability controlling factors and (ii) how these factors are affected by drinking water production and distribution conditions. In addition, (iii) the concept of biological stability is discussed in light of experience with well-established and new analytical methods, enabling high throughput analysis and in-depth characterization of bacterial communities in drinking water. We discussed, how knowledge gained from novel techniques will improve design and monitoring of water treatment and distribution systems in order

  3. Biological stability of drinking water: controlling factors, methods and challenges

    Directory of Open Access Journals (Sweden)

    Emmanuelle ePrest

    2016-02-01

    Full Text Available Biological stability of drinking water refers to the concept of providing consumers with drinking water of same microbial quality at the tap as produced at the water treatment facility. However, uncontrolled growth of bacteria can occur during distribution in water mains and premise plumbing, and can lead to hygienic (e.g. development of opportunistic pathogens, aesthetic (e.g. deterioration of taste, odour, colour or operational (e.g. fouling or biocorrosion of pipes problems. Drinking water contains diverse microorganisms competing for limited available nutrients for growth. Bacterial growth and interactions are regulated by factors such as (i type and concentration of available organic and inorganic nutrients, (ii type and concentration of residual disinfectant, (iii presence of predators such as protozoa and invertebrates, (iv environmental conditions such as water temperature, and (v spatial location of microorganisms (bulk water, sediment or biofilm. Water treatment and distribution conditions in water mains and premise plumbing affect each of these factors and shape bacterial community characteristics (abundance, composition, viability in distribution systems. Improved understanding of bacterial interactions in distribution systems and of environmental conditions impact is needed for better control of bacterial communities during drinking water production and distribution. This article reviews (i existing knowledge on biological stability controlling factors and (ii how these factors are affected by drinking water production and distribution conditions. In addition, (iii the concept of biological stability is discussed in light of experience with well-established and new analytical methods, enabling high throughput analysis and in-depth characterization of bacterial communities in drinking water. We discuss how knowledge gained from novel techniques will improve design and monitoring of water treatment and distribution systems in order to

  4. Hydraulic analysis of water supply networks and controlling the leak using WATER GEMS model

    Directory of Open Access Journals (Sweden)

    Mahmood Motevalizadeh

    2016-03-01

    Full Text Available Given that the discussion on water is strategic in terms of economic and social aspects as well as environmental impact, water leak in urban water-supply systems is very important, so, dealing with it is necessary and inevitable. Controlling and reducing water leak are of the main goals of water supplier organization due to limitations in terms of water resources, especially in dry lands which have few water resources. Pressure management is an efficient tool to reduce costs, enhance the operation of the network and therefore, it reduces the leak and increases the life of facilities and equipment and reduces the number of accidents. Smart pressure containment is a good way to prevent excess pressure in network to control undesirable phenomenon of leak which is directly related to pressure. In this study, Badamuiyeh water supply complex in Kerman City was selected to study on adjusting the pressure to control the leak of water and the hydraulic analysis was performed with demand-based method (DDSM, which is common technique and demand is constant, by Water GEMS software. For this end, the pressure reducing valves (prv were installed in critical point and they were timed to provide standard pressure in all nodes of the network and then, the impact of smart pressure management on water supply system has been investigated. Then its impact on the leak was examined and the results show that smart pressure control through pressure-reducing valve is a proper method for optimal management of water and reducing the leak significantly that with 45.15% reduction in average pressure, one can reduce the leak as much as 25.67% that as its result, 15380 m3 of water is annually saved in this region which is equal to 27.18% of consuming water.

  5. Optimal control of a waste water cleaning plant

    Directory of Open Access Journals (Sweden)

    Ellina V. Grigorieva

    2010-09-01

    Full Text Available In this work, a model of a waste water treatment plant is investigated. The model is described by a nonlinear system of two differential equations with one bounded control. An optimal control problem of minimizing concentration of the polluted water at the terminal time T is stated and solved analytically with the use of the Pontryagin Maximum Principle. Dependence of the optimal solution on the initial conditions is established. Computer simulations of a model of an industrial waste water treatment plant show the advantage of using our optimal strategy. Possible applications are discussed.

  6. Environmental control on cold-water carbonate mounds development

    Science.gov (United States)

    Rüggeberg, A.; Liebetrau, V.; Raddatz, J.; Flögel, S.; Dullo, W.-Chr.; Exp. 307 Scientific Party, Iodp

    2009-04-01

    Cold-water coral reefs are very abundant along the European continental margin in intermediate water depths and are able to build up large mound structures. These carbonate mounds particularly occur in distinct mound provinces on the Irish and British continental margins. Previous investigations resulted in a better understanding of the cold-water coral ecology and the development of conceptual models to explain carbonate mound build-up. Two different hypotheses were evoked to explain the origin and development of carbonate mounds, external versus internal control (e.g., Freiwald et al. 2004 versus e.g. Hovland 1990). Several short sediment cores have been obtained from Propeller Mound, Northern Porcupine Seabight, indicating that cold-water corals grew during interglacial and warm interstadial periods of the Late Pleistocene controlled by environmental and climatic variability supporting the external control hypothesis (e.g. Dorschel et al. 2005, R

  7. Operational water management of Rijnland water system and pilot of ensemble forecasting system for flood control

    Science.gov (United States)

    van der Zwan, Rene

    2013-04-01

    The Rijnland water system is situated in the western part of the Netherlands, and is a low-lying area of which 90% is below sea-level. The area covers 1,100 square kilometres, where 1.3 million people live, work, travel and enjoy leisure. The District Water Control Board of Rijnland is responsible for flood defence, water quantity and quality management. This includes design and maintenance of flood defence structures, control of regulating structures for an adequate water level management, and waste water treatment. For water quantity management Rijnland uses, besides an online monitoring network for collecting water level and precipitation data, a real time control decision support system. This decision support system consists of deterministic hydro-meteorological forecasts with a 24-hr forecast horizon, coupled with a control module that provides optimal operation schedules for the storage basin pumping stations. The uncertainty of the rainfall forecast is not forwarded in the hydrological prediction. At this moment 65% of the pumping capacity of the storage basin pumping stations can be automatically controlled by the decision control system. Within 5 years, after renovation of two other pumping stations, the total capacity of 200 m3/s will be automatically controlled. In critical conditions there is a need of both a longer forecast horizon and a probabilistic forecast. Therefore ensemble precipitation forecasts of the ECMWF are already consulted off-line during dry-spells, and Rijnland is running a pilot operational system providing 10-day water level ensemble forecasts. The use of EPS during dry-spells and the findings of the pilot will be presented. Challenges and next steps towards on-line implementation of ensemble forecasts for risk-based operational management of the Rijnland water system will be discussed. An important element in that discussion is the question: will policy and decision makers, operator and citizens adapt this Anticipatory Water

  8. How to Identify and Control Water Weeds and Algae.

    Science.gov (United States)

    Applied Biochemists, Inc., Mequon, WI.

    Included in this guide to water management are general descriptions of algae, toxic algae, weed problems in lakes, ponds, and canals, and general discussions of mechanical, biological and chemical control methods. In addition, pictures, descriptions, and recommended control methods are given for algae, 6 types of floating weeds, 18 types of…

  9. How to Identify and Control Water Weeds and Algae.

    Science.gov (United States)

    Applied Biochemists, Inc., Mequon, WI.

    Included in this guide to water management are general descriptions of algae, toxic algae, weed problems in lakes, ponds, and canals, and general discussions of mechanical, biological and chemical control methods. In addition, pictures, descriptions, and recommended control methods are given for algae, 6 types of floating weeds, 18 types of…

  10. Genetic and physiological controls of growth under water deficit.

    Science.gov (United States)

    Tardieu, François; Parent, Boris; Caldeira, Cecilio F; Welcker, Claude

    2014-04-01

    The sensitivity of expansive growth to water deficit has a large genetic variability, which is higher than that of photosynthesis. It is observed in several species, with some genotypes stopping growth in a relatively wet soil, whereas others continue growing until the lower limit of soil-available water. The responses of growth to soil water deficit and evaporative demand share an appreciable part of their genetic control through the colocation of quantitative trait loci as do the responses of the growth of different organs to water deficit. This result may be caused by common mechanisms of action discussed in this paper (particularly, plant hydraulic properties). We propose that expansive growth, putatively linked to hydraulic processes, determines the sink strength under water deficit, whereas photosynthesis determines source strength. These findings have large consequences for plant modeling under water deficit and for the design of breeding programs.

  11. The last gasp: controlling water production in wells

    Energy Technology Data Exchange (ETDEWEB)

    Lea, N.

    2002-03-01

    Produced water in oil and gas wells is highly undesirable. As it grows it saps productivity until wells finally shut-in. This article discusses a number of methods that have been tried over time with varying degrees of success and failure to control water influx into wells with operating and completion techniques. Water blocking chemicals that form downhole rubber-like barriers, sealing the water-producing zone from the oil and gas producing zones have had some recent successes, but performance has not always lived up to the salesman's claims. More success has been achieved with the downhole oil/water separation technology developed during the late 1990s by C{sub F}ER Technologies, which has since been licensed to Baker Hughes and Schlumberger. This technology essentially captures the hydrocarbon fluids into two streams -- one stream is clean water, which is then reinjected downhole, and the second oil-rich stream is brought to the surface where a hydrocyclone uses centrifugal forces to separate the oil from the water. Among the water blocking chemical technologies UNOCAL's gel placement technique has had some success. Once the produced water's origin is determined from production data, a liquid gel is injected downhole followed by nitrogen gas which helps position the gel within the wellbore while it hardens. Ideally, the produced water will enter the wellbore beneath the hardened gel while the oil or gas is above the gel plug. Aqueolic Canada's 'Direxit' is a newer water blocking chemical with a viscosity of one to three centipoise, resulting in low injection pressure. To eliminate problems with swelling clays Direxit can be also mixed with potassium chloride. Aqueolic has also filed notice of testing 'Bloxit' a water-blocking polymer with a density less than water, thus having the ability to float above a water producing zone.

  12. Dynamics of controlled release systems based on water-in-water emulsions: A general theory

    NARCIS (Netherlands)

    Sagis, L.M.C.

    2008-01-01

    Phase-separated biopolymer solutions, and aqueous dispersions of hydrogel beads, liposomes, polymersomes, aqueous polymer microcapsules, and colloidosomes are all examples of water-in-water emulsions. These systems can be used for encapsulation and controlled release purposes, in for example food or

  13. Model Design for Water Wheel Control System of Heumgyeonggaknu

    Science.gov (United States)

    Kim, Sang Hyuk; Ham, Seon Young; Lee, Yong Sam

    2016-03-01

    Heumgyeonggaknu (????) is powered by a water-hammering-type water wheel. The technique that maintains the constant speed of the water wheel is assumed to be the one used in the Cheonhyeong (???) apparatus in Shui Yun Yi Xiang Tai (???) made by the Northern Song (??) dynasty in the 11th century. We investigated the history of the development and characteristics of the Cheonhyeong apparatus, and we analyzed ways to transmit the power of Heumgyeonggaknu. In addition, we carried out a conceptual design to systematically examine the power control system. Based on the conceptual design, we built a model for a water wheel control system that could be used in experiments by drawing a 3D model and a basic design.

  14. Isotopic Controls of Rainwater and Water Vapor on Mangrove Leaf Water and Lipid Biomarkers

    Science.gov (United States)

    Ladd, N.; Wolfshorndl, M.; Sachs, J. P.

    2015-12-01

    Hydrogen isotope ratios (2H/1H or δ2H) of sedimentary mangrove lipid biomarkers can be used as a proxy of past salinity and water isotopes. This approach is based on the observation that apparent 2H/1H fractionation between surface water and mangrove lipids increases with surface water salinity in six species of mangroves with different salt management strategies growing at sites spanning a range of relative humidities throughout Australia and Micronesia. In order to more robustly apply mangrove lipid δ2H as a paleoclimate proxy, we investigated the cause of the correlation between apparent 2H fractionation and salinity. We present results from two related experiments that assessed controls on isotopes of mangrove leaf water, the direct source of hydrogen in lipids: (1) Measurements of natural δ2H in precipitation, surface water, and mangrove tissue water from a series of lakes with varying salinity and water isotope composition in Palau, and (2) measurements of mangrove tissue water and treatment water from a controlled simulation in which mangroves were treated with artificial rain of varying isotopic composition. Rainwater 2H/1H fluctuations of 30‰ over a one-month period explain up to 65% of the variance in leaf water δ2H for Bruguiera gymnorhiza mangroves from Palau despite lake water isotope differences among sites of up to 35‰. This indicates that in humid tropical settings, leaf water isotopes are more closely related to those of precipitation and water vapor than to those of lake surface water, explaining the observed change in apparent fractionation in B. gymnorhiza lipids with salinity. The relationship between leaf water and rainwater isotopes may be due to either equilibration of leaf water with water vapor in the nearly saturated air or direct foliar uptake of rain and/or dew. Foliar uptake is an important water source for many plants, but has not been documented in mangroves. We tested the capacity for mangroves to perform this function by

  15. Structure and Controls of the Global Virtual Water Trade Network

    Science.gov (United States)

    Suweis, S. S.

    2011-12-01

    Recurrent or ephemeral water shortages are a crucial global challenge, in particular because of their impacts on food production. The global character of this challenge is reflected in the trade among nations of virtual water, i.e. the amount of water used to produce a given commodity. We build, analyze and model the network describing the transfer of virtual water between world nations for staple food products. We find that all the key features of the network are well described by a model, the fitness model, that reproduces both the topological and weighted properties of the global virtual water trade network, by assuming as sole controls each country's gross domestic product and yearly rainfall on agricultural areas. We capture and quantitatively describe the high degree of globalization of water trade and show that a small group of nations play a key role in the connectivity of the network and in the global redistribution of virtual water. Finally, we illustrate examples of prediction of the structure of the network under future political, economic and climatic scenarios, suggesting that the crucial importance of the countries that trade large volumes of water will be strengthened. Our results show the importance of incorporating a network framework in the study of virtual water trades and provide a model to study the structure and resilience of the GVWTN under future scenarios for social, economic and climate change.

  16. Strategies to water pollution control in western China

    Institute of Scientific and Technical Information of China (English)

    JIANGWenchao; CHENGJijian; LONGTengrui; HEQiang

    2003-01-01

    Problems of and main limiting factors to Chinese western eco-environment are analyzea firstly and principles of integrating water pollution control with water resources planning and management, with ecological construction and with economic development planning and setting control priorities according to local conditions are proposed. Following strategies for water pollution control are suggested: 1) a master plan for western area need to be established as soon as possible; 2) total emission control should be regarded as the basic policy and measures such as clean production, charging and subsidy need to be implemented; 3) point sources pollution control should be considered the main task in short term and centralized wasteweter treatment plants by using sustainable processes should be constructed primarily for large and medium-size cities with heavier pollution; 4) sound institutional and regulation systems need to be established to create an enabling environment; 5) multiple investment system should be established; and 6) studies of pragmatic theories and methodologies for water pollution control and cost-effective technologies appropriate to western area, and training of local technicians need to be enhanced as well.

  17. Decision model to control water losses in distribution networks

    Directory of Open Access Journals (Sweden)

    Marcele Elisa Fontana

    2016-01-01

    Full Text Available Abstract The losses in the urban water supply networks have become a growing concern. There are several alternatives for the quantification, detection and monitoring of water losses. However, in general, water companies have budgetary and other constraints that hinder implementation. Therefore, this paper presents a model to aid the selection of a subset of preventive maintenance actions to control water losses while accounting for the water companies’ restrictions. The model combines an additive multi-attribute value analysis by applying the SMARTER method to evaluate alternatives with Integer Linear Programming (ILP. The model shows to be efficient in order to achieve a portfolio of preventive maintenance actions, particularly when the decision maker considers that, there is a compensation for attribute evaluations.

  18. Control of mitochondrial volume by mitochondrial metabolic water.

    Science.gov (United States)

    Casteilla, Louis; Devin, Anne; Carriere, Audrey; Salin, Bénédicte; Schaeffer, Jacques; Rigoulet, Michel

    2011-11-01

    It is well-known that mitochondrial volume largely controls mitochondrial functioning. We investigate whether metabolic water produced by oxidative phosphorylation could be involved in mitochondrial volume regulation. We modulated the generation of this water in liver mitochondria and assess their volume by two independent techniques. In liver mitochondria, the mitochondrial volume was specifically decreased when no water was produced independently of energetic parameters and uncoupling activity. In all other conditions associated with water generation, there was no significant change in mitochondrial metabolic volume. Altogether these data demonstrate that mitochondrial volume is regulated, independently of energetic status, by the mitochondrial metabolic water that acts as a signal. Copyright © 2011 Elsevier B.V. and Mitochondria Research Society. All rights reserved. All rights reserved.

  19. Conjunctively optimizing flash flood control and water quality in urban water reservoirs by model predictive control and dynamic emulation

    Science.gov (United States)

    Galelli, Stefano; Goedbloed, Albert; Schmitter, Petra; Castelletti, Andrea

    2014-05-01

    Urban water reservoirs are a viable adaptation option to account for increasing drinking water demand of urbanized areas as they allow storage and re-use of water that is normally lost. In addition, the direct availability of freshwater reduces pumping costs and diversifies the portfolios of drinking water supply. Yet, these benefits have an associated twofold cost. Firstly, the presence of large, impervious areas increases the hydraulic efficiency of urban catchments, with short time of concentration, increased runoff rates, losses of infiltration and baseflow, and higher risk of flash floods. Secondly, the high concentration of nutrients and sediments characterizing urban discharges is likely to cause water quality problems. In this study we propose a new control scheme combining Model Predictive Control (MPC), hydro-meteorological forecasts and dynamic model emulation to design real-time operating policies that conjunctively optimize water quantity and quality targets. The main advantage of this scheme stands in its capability of exploiting real-time hydro-meteorological forecasts, which are crucial in such fast-varying systems. In addition, the reduced computational requests of the MPC scheme allows coupling it with dynamic emulators of water quality processes. The approach is demonstrated on Marina Reservoir, a multi-purpose reservoir located in the heart of Singapore and characterized by a large, highly urbanized catchment with a short (i.e. approximately one hour) time of concentration. Results show that the MPC scheme, coupled with a water quality emulator, provides a good compromise between different operating objectives, namely flood risk reduction, drinking water supply and salinity control. Finally, the scheme is used to assess the effect of source control measures (e.g. green roofs) aimed at restoring the natural hydrological regime of Marina Reservoir catchment.

  20. Practical Optimal Control of Large-scale Water Distribution Network

    Institute of Scientific and Technical Information of China (English)

    Lv Mou(吕谋); Song Shuang

    2004-01-01

    According to the network characteristics and actual state of the water supply system in China, the implicit model, which can be solved by the hierarchical optimization method, was established. In special, based on the analyses of the water supply system containing variable-speed pumps, a software has been developed successfully. The application of this model to the city of Hangzhou (China) was compared to experiential strategy. The results of this study showed that the developed model is a promising optimization method to control the large-scale water supply systems.

  1. Options for water-level control in developed wetlands

    Science.gov (United States)

    Kelley, J. R.; Laubhan, M. K.; Reid, F. A.; Wortham, J. S.; Fredrickson, L. H.

    1993-01-01

    Wetland habitats in the United States currently are lost at a rate of 260,000 acres/year (105,218 ha/year). Consequently, water birds concentrate in fewer and smaller areas. Such concentrations may deplete food supplies and influence behavior, physiology, and survival. Continued losses increase the importance of sound management of the remaining wetlands because water birds depend on them. Human activities modified the natural hydrology of most remaining wetlands in the conterminous United States, and such hydrologic alterations frequently reduce wetland productivity. The restoration of original wetland functions and productivity often requires the development of water distribution and discharge systems to emulate natural hydrologic regimes. Construction of levees and correct placement of control structures and water-delivery and water-discharge systems are necessary to (1) create soil and water conditions for the germination of desirable plants, (2) control nuisance vegetation, (3) promote the production of invertebrates, and (4) make foods available for wildlife that depends of wetlands (Leaflets 13.2.1 and 13.4.6). This paper provides basic guidelines for the design of wetlands that benefit wildlife. If biological considerations are not incorporated into such designs, the capability of managing wetlands for water birds is reduced and costs often are greater. Although we address the development of palustrine wetlands in migration and wintering areas, many of the discussed principles are applicable to the development of other wetland types and in other locations.

  2. Process Control for Precipitation Prevention in Space Water Recovery Systems

    Science.gov (United States)

    Sargusingh, Miriam; Callahan, Michael R.; Muirhead, Dean

    2015-01-01

    The ability to recover and purify water through physiochemical processes is crucial for realizing long-term human space missions, including both planetary habitation and space travel. Because of their robust nature, rotary distillation systems have been actively pursued by NASA as one of the technologies for water recovery from wastewater primarily comprised of human urine. A specific area of interest is the prevention of the formation of solids that could clog fluid lines and damage rotating equipment. To mitigate the formation of solids, operational constraints are in place that limits such that the concentration of key precipitating ions in the wastewater brine are below the theoretical threshold. This control in effected by limiting the amount of water recovered such that the risk of reaching the precipitation threshold is within acceptable limits. The water recovery limit is based on an empirically derived worst case wastewater composition. During the batch process, water recovery is estimated by monitoring the throughput of the system. NASA Johnson Space Center is working on means of enhancing the process controls to increase water recovery. Options include more precise prediction of the precipitation threshold. To this end, JSC is developing a means of more accurately measuring the constituent of the brine and/or wastewater. Another means would be to more accurately monitor the throughput of the system. In spring of 2015, testing will be performed to test strategies for optimizing water recovery without increasing the risk of solids formation in the brine.

  3. A vadose zone water fluxmeter with divergence control

    Science.gov (United States)

    Gee, G. W.; Ward, A. L.; Caldwell, T. G.; Ritter, J. C.

    2002-08-01

    Unsaturated water flux densities are needed to quantify water and contaminant transfer within the vadose zone. However, water flux densities are seldom measured directly and often are predicted with uncertainties of an order or magnitude or more. A water fluxmeter was designed, constructed, and tested to directly measure drainage fluxes in field soils. The fluxmeter was designed to minimize divergence. It concentrates flow into a narrow sensing region filled with a fiberglass wick. The wick applies suction, proportional to its length, and passively drains the meter. The meter can be installed in an augured borehole at almost any depth below the root zone. Water flux through the meter is measured with a self-calibrating tipping bucket, with a sensitivity of ~4 mL tip-1. For our meter this is equivalent to detection limit of ~0.1 mm. Passive-wick devices previously have not properly corrected for flow divergence. Laboratory measurements supported predictions of a two-dimensional (2-D) numerical model, which showed that control of the collector height H and knowledge of soil hydraulic properties are required for improving divergence control, particularly at fluxes below 1000 mm yr-1. The water fluxmeter is simple in concept, is inexpensive, and has the capability of providing continuous and reliable monitoring of unsaturated water fluxes ranging from less than 1 mm yr-1 to more than 1000 mm yr-1.

  4. Rootstock control of scion transpiration and its acclimation to water deficit are controlled by different genes.

    Science.gov (United States)

    Marguerit, Elisa; Brendel, Oliver; Lebon, Eric; Van Leeuwen, Cornelis; Ollat, Nathalie

    2012-04-01

    The stomatal control of transpiration is one of the major strategies by which plants cope with water stress. Here, we investigated the genetic architecture of the rootstock control of scion transpiration-related traits over a period of 3 yr. The rootstocks studied were full sibs from a controlled interspecific cross (Vitis vinifera cv. Cabernet Sauvignon × Vitis riparia cv. Gloire de Montpellier), onto which we grafted a single scion genotype. After 10 d without stress, the water supply was progressively limited over a period of 10 d, and a stable water deficit was then applied for 15 d. Transpiration rate was estimated daily and a mathematical curve was fitted to its response to water deficit intensity. We also determined δ(13) C values in leaves, transpiration efficiency and water extraction capacity. These traits were then analysed in a multienvironment (year and water status) quantitative trait locus (QTL) analysis. Quantitative trait loci, independent of year and water status, were detected for each trait. One genomic region was specifically implicated in the acclimation of scion transpiration induced by the rootstock. The QTLs identified colocalized with genes involved in water deficit responses, such as those relating to ABA and hydraulic regulation. Scion transpiration rate and its acclimation to water deficit are thus controlled genetically by the rootstock, through different genetic architectures. © 2012 INRA. New Phytologist © 2012 New Phytologist Trust.

  5. Saline water pollution in groundwater: issues and its control

    Directory of Open Access Journals (Sweden)

    Setyawan Purnama

    2012-10-01

    Full Text Available Nowadays, saline water pollution has been gaining its importance as the major issue around the world, especially in the urban coastal area. Saline water pollution has major impact on human life and livelihood. It´s mainly a result from static fossil water and the dynamics of sea water intrusion.. The problem of saline water pollution caused by seawater intrusion has been increasing since the beginning of urban population. The problem of sea water intrusion in the urban coastal area must be anticipated as soon as possible especially in the urban areas developed in coastal zones,. This review article aims to; (i analyze the distribution of saline water pollution on urban coastal area in Indonesia and (ii analyze some methods in controlling saline water pollution, especially due to seawater intrusion in urban coastal area. The strength and weakness of each method have been compared, including (a applying different pumping patterns, (b artificial recharge, (c extraction barrier, (d injection barrier and (e subsurface barrier. The best method has been selected considering its possible development in coastal areas of developing countries. The review is based considering the location of Semarang coastal area, Indonesia. The results have shown that artificial recharge and extraction barrier are the most suitable methods to be applied in the area.

  6. Assessment of Ilam Reservoir Eutrophication Response in Controlling Water Inflow

    Directory of Open Access Journals (Sweden)

    Fereshteh Nourmohammadi Dehbalaei

    2016-12-01

    Full Text Available In this research, a 2D laterally averaged model of hydrodynamics and water quality, CE-QUAL-W2, was applied to simulate water quality parameters in the Ilam reservoir. The water quality of Ilam reservoir was obtained between mesotrophic and eutrophic based on the measured data including chlorophyll a, total phosphorus and subsurface oxygen saturation. The CE-QUAL-W2 model was calibrated and verified by using the data of the year 2009 and 2010, respectively. Nutrients, chlorophyll a and dissolved oxygen were the water quality constituents simulated by the CE-QUAL-W2 model. The comparison of the simulated water surface elevation with the measurement records indicated that the flow was fully balanced in the numerical model. There was a good agreement between the simulated and measured results of the hydrodynamics and water quality constituents in the calibration and verification periods. Some scenarios have been made base on decreasing in water quantity and nutrient inputs of reservoir inflows. The results have shown that the water quality improvements of the Ilam reservoir will not be achieved by reducing a portion of the reservoir inflow. The retention time of water in reservoir would be changed by decreasing of inflows and it made of the negative effects on the chlorophyll-a concentration by reduction of nutrient inputs and keeping constant of discharge inflow to reservoir, the concentration of total phosphorus would be significantly changed and also the concentration of chlorophyll-a was constant approximately. Thus, the effects of control in nutrient inputs are much more than control in discharge inflows in the Ilam reservoir.

  7. Controlled iodine release from polyurethane sponges for water decontamination.

    Science.gov (United States)

    Aviv, Oren; Laout, Natalia; Ratner, Stanislav; Harik, Oshrat; Kunduru, Konda Reddy; Domb, Abraham J

    2013-12-28

    Iodinated polyurethane (IPU) sponges were prepared by immersing sponges in aqueous/organic solutions of iodine or exposing sponges to iodine vapors. Iodine was readily adsorbed into the polymers up to 100% (w/w). The adsorption of iodine on the surface was characterized by XPS and SEM analyses. The iodine loaded IPU sponges were coated with ethylene vinyl acetate (EVA), in order to release iodine in a controlled rate for water decontamination combined with active carbon cartridge, which adsorbs the iodine residues after the microbial inactivation. The EVA coated IPU were incorporated in a water purifier and tested for iodine release to water and for microbial inactivation efficiency according to WQA certification program against P231/EPA for 250l, using 25l a day with flow rate of 6-8min/1l. The antimicrobial activity was also studied against Escherichia coli and MS2 phage. Bacterial results exceeded the minimal requirement for bacterial removal of 6log reduction throughout the entire lifespan. At any testing point, no bacteria was detected in the outlet achieving more than 7.1 to more than 8log reduction as calculated upon the inlet concentration. Virus surrogate, MS2, reduction results varied from 4.11log reduction under tap water, and 5.11log reduction under basic water (pH9) to 1.32 for acidic water (pH5). Controlled and stable iodine release was observed with the EVA coated IPU sponges and was effective in deactivating the bacteria and virus present in the contaminated water and thus, these iodinated PU systems could be used in water purification to provide safe drinking water. These sponges may find applications as disinfectants in medicine.

  8. Environmental control on aerobic methane oxidation in coastal waters

    Science.gov (United States)

    Steinle, Lea; Maltby, Johanna; Engbersen, Nadine; Zopfi, Jakob; Bange, Hermann; Elvert, Marcus; Hinrichs, Kai-Uwe; Kock, Annette; Lehmann, Moritz; Treude, Tina; Niemann, Helge

    2016-04-01

    Large quantities of methane are produced in anoxic sediments of continental margins and may be liberated to the overlying water column, where some of it is consumed by aerobic methane oxidizing bacteria (MOB). Aerobic methane oxidation (MOx) in the water column is consequently the final sink for methane before its release to the atmosphere, where it acts as a potent greenhouse gas. In the context of the ocean's contribution to atmospheric methane, coastal seas are particularly important accounting >75% of global methane emission from marine systems. Coastal oceans are highly dynamic, in particular with regard to the variability of methane and oxygen concentrations as well as temperature and salinity, all of which are potential key environmental factors controlling MOx. To determine important environmental controls on the activity of MOBs in coastal seas, we conducted a two-year time-series study with measurements of physicochemical water column parameters, MOx activity and the composition of the MOB community in a coastal inlet in the Baltic Sea (Boknis Eck Time Series Station, Eckernförde Bay - E-Bay). In addition, we investigated the influence of temperature and oxygen on MOx during controlled laboratory experiments. In E-Bay, hypoxia developed in bottom waters towards the end of the stratification period. Constant methane liberation from sediments resulted in bottom water methane accumulations and supersaturation (with respect to the atmospheric equilibrium) in surface waters. Here, we will discuss the factors impacting MOx the most, which were (i) perturbations of the water column (ii) temperature and (iii) oxygen concentration. (i) Perturbations of the water column caused by storm events or seasonal mixing led to a decrease in MOx, probably caused by replacement of stagnant water with a high standing stock of MOB by 'new' waters with a lower abundance of methanotrophs. b) An increase in temperature generally led to higher MOx rates. c) Even though methane was

  9. Adaptive Reference Control for Pressure Management in Water Networks

    DEFF Research Database (Denmark)

    Kallesøe, Carsten; Jensen, Tom Nørgaard; Wisniewski, Rafal

    2015-01-01

    Water scarcity is an increasing problem worldwide and at the same time a huge amount of water is lost through leakages in the distribution network. It is well known that improved pressure control can lower the leakage problems. In this work water networks with a single pressure actuator and several...... consumers are considered. Under mild assumptions on the consumption pattern and hydraulic resistances of pipes we use properties of the network graph and Kirchhoffs node and mesh laws to show that simple relations exist between the actuator pressure and critical point pressures inside the network....... Subsequently, these relations are exploited in an adaptive reference control scheme for the actuator pressure that ensures constant pressure at the critical points. Numerical experiments underpin the results. © Copyright IEEE - All rights reserved....

  10. The Role of Monitoring in Controlling Water Pollution

    Science.gov (United States)

    Hirsch, Allan

    1971-01-01

    The purpose of this paper is to provide an overview of trends in the national water pollution control effort and to describe the role of monitoring in that effort, particularly in relation to the responsibilities of the Environmental Protection Agency (EPA). I hope the paper will serve as a useful framework for the more specific discussions of monitoring technology to follow.

  11. Ultrasonic system for operational ecological control of water pollution

    OpenAIRE

    Pohrebennyk, V.; Romanyuk, A.; Politylo, R.

    2013-01-01

    The work is dedicated to the issues of the developing the methods of the data-processing system creation for the ecological control of the water pollution. It was created the methodological approach towards the solving of the tasks based on the simultaneous measurement of the integral, selective and hydro-physical parameters and geographical coordinates.

  12. THE CORROSION CONTROL-WATER QUALITY SPIDER WEB

    Science.gov (United States)

    This presentation provides an overview of new research results and emerging research needs with respect to both corrosion control issues, (lead, copper, iron) and to issues of inorganic contaminants that can form or accumulate in distribution system, water, pipe scales and distri...

  13. AN INTERDISCIPLINARY APPROACH TO VALUING WATER FROM BRUSH CONTROL

    Science.gov (United States)

    An analytical methodology utilizing models from three disciplines is developed to assess the viability of brush control for wate yield in the Frio River Basin, TX. Ecological, hydrologic, and economic models are used to portray changes in forage production and water supply result...

  14. Control algorithm for multiscale flow simulations of water

    DEFF Research Database (Denmark)

    Kotsalis, E. M.; Walther, Jens Honore; Kaxiras, E.

    2009-01-01

    . The use of a mass conserving specular wall results in turn to spurious oscillations in the density profile of the atomistic description of water. These oscillations can be eliminated by using an external boundary force that effectively accounts for the virial component of the pressure. In this Rapid......We present a multiscale algorithm to couple atomistic water models with continuum incompressible flow simulations via a Schwarz domain decomposition approach. The coupling introduces an inhomogeneity in the description of the atomistic domain and prevents the use of periodic boundary conditions...... Communication, we extend a control algorithm, previously introduced for monatomic molecules, to the case of atomistic water and demonstrate the effectiveness of this approach. The proposed computational method is validated for the cases of equilibrium and Couette flow of water....

  15. Sea-water battery for subsea control systems

    Science.gov (United States)

    Hasvold, Øistein; Henriksen, Henrich; Melv˦r, Einar; Citi, Gianfederico; Johansen, Bent Ø.; Kjønigsen, Tom; Galetti, Robin

    This paper describes a power source for the autonomous control system of a subsea well (SWACS) in the Ionian Sea. The unit was deployed in Jan. 1996 at a depth of 180 m. The 650 kWh sea-water battery uses anodes made from commercial magnesium alloys, sea-water as the electrolyte and oxygen dissolved in the sea-water as oxidant. The inert cathodes are made from carbon fibers. The system is composed of six, two-metre high sea-water cells integrated in a steel structure, a d.c./d.c. converter and a valve regulated lead-acid accumulator enclosed in a titanium container together with a monitoring unit which transfers data to the surface via an acoustic link.

  16. Optimal drinking water composition for caries control in populations

    DEFF Research Database (Denmark)

    Bruvo, M.; Ekstrand, K.; Arvin, Erik;

    2008-01-01

    Apart from the well-documented effect of fluoride in drinking water on dental caries, little is known about other chemical effects. Since other ions in drinking water may also theoretically influence caries, as well as binding of fluoride in the oral environment, we hypothesized that the effect...... of drinking water on caries may not be limited to fluoride only. Among 22 standard chemical variables, including 15 ions and trace elements as well as gases, organic compounds, and physical measures, iterative search and testing identified that calcium and fluoride together explained 45% of the variations...... in the numbers of decayed, filled, and missing tooth surfaces (DMF-S) among 52,057 15-year-old schoolchildren in 249 Danish municipalities. Both ions had reducing effects on DMF-S independently of each other, and could be used in combination for the design of optimal drinking water for caries control...

  17. Control algorithm for multiscale flow simulations of water

    Science.gov (United States)

    Kotsalis, Evangelos M.; Walther, Jens H.; Kaxiras, Efthimios; Koumoutsakos, Petros

    2009-04-01

    We present a multiscale algorithm to couple atomistic water models with continuum incompressible flow simulations via a Schwarz domain decomposition approach. The coupling introduces an inhomogeneity in the description of the atomistic domain and prevents the use of periodic boundary conditions. The use of a mass conserving specular wall results in turn to spurious oscillations in the density profile of the atomistic description of water. These oscillations can be eliminated by using an external boundary force that effectively accounts for the virial component of the pressure. In this Rapid Communication, we extend a control algorithm, previously introduced for monatomic molecules, to the case of atomistic water and demonstrate the effectiveness of this approach. The proposed computational method is validated for the cases of equilibrium and Couette flow of water.

  18. Structure and Controls of the Global Virtual Water Trade Network

    CERN Document Server

    Suweis, S; Dalin, C; Hanasaki, N; Rinaldo, A; Rodriguez-Iturbe, I; 10.1029/2011GL046837

    2012-01-01

    Recurrent or ephemeral water shortages are a crucial global challenge, in particular because of their impacts on food production. The global character of this challenge is reflected in the trade among nations of virtual water, i.e. the amount of water used to produce a given commodity. We build, analyze and model the network describing the transfer of virtual water between world nations for staple food products. We find that all the key features of the network are well described by a model that reproduces both the topological and weighted properties of the global virtual water trade network, by assuming as sole controls each country's gross domestic product and yearly rainfall on agricultural areas. We capture and quantitatively describe the high degree of globalization of water trade and show that a small group of nations play a key role in the connectivity of the network and in the global redistribution of virtual water. Finally, we illustrate examples of prediction of the structure of the network under fut...

  19. Metasomatic control of water contents in the Kaapvaal cratonic mantle

    Science.gov (United States)

    Peslier, A. H.; Woodland, A. B.; Bell, D. R.; Lazarov, M.; Lapen, T. J.

    2012-11-01

    Water and trace element contents were measured by FTIR and laser ablation-ICPMS on minerals from peridotite xenoliths in kimberlites of the Kaapvaal craton from Finsch, Kimberley, Jagersfontein (South Africa), Letseng-La-Terae, and Liqhobong (Lesotho) mines. The peridotites record a wide range of pressure, temperature, oxygen fugacity, and metasomatic events. Correlations between water content or OH vibration bands with major, minor and trace elements in pyroxene and garnet precludes disturbance during xenolith entrainment by the host kimberlite magma and indicate preservation of mantle water contents. Clinopyroxene water contents (150-400 ppm H2O, by weight) correlate with those of orthopyroxene (40-250 ppm). Olivines (Peslier et al., 2008, 2010) and garnets have 0-86 and 0-20 ppm H2O, respectively. Relations in individual xenolith suites between the amount of water and that of incompatible elements Ti, Na, Fe3+ and rare earths in minerals suggests that metasomatism by oxidizing melts controls the water content of olivine, pyroxene and garnet. At pressures ⩽5.5 GPa, hydrous, alkaline, siliceous fluids or melts metasomatized Liqhobong and Kimberley peridotites, producing high water contents in their olivine, pyroxenes and garnet. At higher pressures, the percolation of ultramafic melts reacting with peridotite resulted in co-variation of Ca, Ti and water at the edge of garnets at Jagersfontein, and the overall crystallization of garnet with lower water contents than those in the original peridotites. The upward migration of these ultramafic melts through the lithospheric mantle also increased the water content of olivines with decreasing pressure at Finsch Mine. H2O/Ce ratios of melts in equilibrium with Kaapvaal peridotites range from 100 to 20,000 and the larger values may indicate metasomatism in subduction zone settings. Metasomatic events in Kaapvaal peridotites are thought to have occurred from the Archean to the Mesozoic. However, circumstantial evidence

  20. 33 CFR 222.5 - Water control management (ER 1110-2-240).

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Water control management (ER 1110... ARMY, DEPARTMENT OF DEFENSE ENGINEERING AND DESIGN § 222.5 Water control management (ER 1110-2-240). (a... Engineers in carrying out water control management activities, including establishment of water...

  1. Instrumentation and control strategies for an integral pressurized water reactor

    Directory of Open Access Journals (Sweden)

    Belle R. Upadhyaya

    2015-03-01

    Full Text Available Several vendors have recently been actively pursuing the development of integral pressurized water reactors (iPWRs that range in power levels from small to large reactors. Integral reactors have the features of minimum vessel penetrations, passive heat removal after reactor shutdown, and modular construction that allow fast plant integration and a secure fuel cycle. The features of an integral reactor limit the options for placing control and safety system instruments. The development of instrumentation and control (I&C strategies for a large 1,000 MWe iPWR is described. Reactor system modeling—which includes reactor core dynamics, primary heat exchanger, and the steam flashing drum—is an important part of I&C development and validation, and thereby consolidates the overall implementation for a large iPWR. The results of simulation models, control development, and instrumentation features illustrate the systematic approach that is applicable to integral light water reactors.

  2. High Resolution Sensing and Control of Urban Water Networks

    Science.gov (United States)

    Bartos, M. D.; Wong, B. P.; Kerkez, B.

    2016-12-01

    We present a framework to enable high-resolution sensing, modeling, and control of urban watersheds using (i) a distributed sensor network based on low-cost cellular-enabled motes, (ii) hydraulic models powered by a cloud computing infrastructure, and (iii) automated actuation valves that allow infrastructure to be controlled in real time. This platform initiates two major advances. First, we achieve a high density of measurements in urban environments, with an anticipated 40+ sensors over each urban area of interest. In addition to new measurements, we also illustrate the design and evaluation of a "smart" control system for real-world hydraulic networks. This control system improves water quality and mitigates flooding by using real-time hydraulic models to adaptively control releases from retention basins. We evaluate the potential of this platform through two ongoing deployments: (i) a flood monitoring network in the Dallas-Fort Worth metropolitan area that detects and anticipates floods at the level of individual roadways, and (ii) a real-time hydraulic control system in the city of Ann Arbor, MI—soon to be one of the most densely instrumented urban watersheds in the United States. Through these applications, we demonstrate that distributed sensing and control of water infrastructure can improve flash flood predictions, emergency response, and stormwater contaminant mitigation.

  3. P controller with partial feed forward compensation and decoupling control for the steam generator water level

    Energy Technology Data Exchange (ETDEWEB)

    Liu Cheng, E-mail: liuch_2004@stu.xjtu.edu.c [School of Energy and Power Engineering, Xi' an Jiaotong University, Xi' an, Shaanxi 710049 (China); Zhao Fuyu; Hu Ping; Hou Suxia; Li Chong [School of Energy and Power Engineering, Xi' an Jiaotong University, Xi' an, Shaanxi 710049 (China)

    2010-01-15

    In this paper, a P controller with partial feed forward compensation and decoupling control for the steam generator water level is presented. While taking the steam flowrate as a disturbance to water level, the controller design can be completed in three stages. (1) Main circuit controller is designed without regard to disturbance. Since the transfer function of the steam generator model contains integrate element and differential element, the proportional (P) controller can selected as main circuit controller instead of PID controller for steam generator water level. (2) Partial feed forward compensation is introduced to remove the disturbance from the steam flowrate. If disregarding the differential element, the partial feed forward compensation's designing turns to be very simple. Partial feed forward compensation coefficient is set as reciprocal of P controller gain. (3) The coupling effects between the water level regulating and steam flowrate disturbance can be decreased by model reference decoupling control. The proposed methodology shows satisfactory transient responses, disturbance rejection and robustness.

  4. Skin lipid structure controls water permeability in snake molts.

    Science.gov (United States)

    Torri, Cristian; Mangoni, Alfonso; Teta, Roberta; Fattorusso, Ernesto; Alibardi, Lorenzo; Fermani, Simona; Bonacini, Irene; Gazzano, Massimo; Burghammer, Manfred; Fabbri, Daniele; Falini, Giuseppe

    2014-01-01

    The role of lipids in controlling water exchange is fundamentally a matter of molecular organization. In the present study we have observed that in snake molt the water permeability drastically varies among species living in different climates and habitats. The analysis of molts from four snake species: tiger snake, Notechis scutatus, gabon viper, Bitis gabonica, rattle snake, Crotalus atrox, and grass snake, Natrix natrix, revealed correlations between the molecular composition and the structural organization of the lipid-rich mesos layer with control in water exchange as a function of temperature. It was discovered, merging data from micro-diffraction and micro-spectroscopy with those from thermal, NMR and chromatographic analyses, that this control is generated from a sophisticated structural organization that changes size and phase distribution of crystalline domains of specific lipid molecules as a function of temperature. Thus, the results of this research on four snake species suggest that in snake skins different structured lipid layers have evolved and adapted to different climates. Moreover, these lipid structures can protect, "safety", the snakes from water lost even at temperatures higher than those of their usual habitat.

  5. 14 CFR 1274.926 - Clean Air-Water Pollution Control Acts.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 5 2010-01-01 2010-01-01 false Clean Air-Water Pollution Control Acts...-Water Pollution Control Acts. Clean Air-Water Pollution Control Acts July 2002 If this cooperative... 91-604) and section 308 of the Federal Water Pollution Control Act, as amended (33 U.S.C. 1251 et...

  6. Ecohydrological controls over water budgets in floodplain meadows

    Science.gov (United States)

    Morris, Paul J.; Verhoef, Anne; Macdonald, David M. J.; Gardner, Cate M.; Punalekar, Suvarna M.; Tatarenko, Irina; Gowing, David

    2013-04-01

    Floodplain meadows are important ecosystems, characterised by high plant species richness including rare species. Fine-scale partitioning along soil hydrological gradients allows many species to co-exist. Concerns exist that even modest changes to soil hydrological regime as a result of changes in management or climate may endanger floodplain meadows communities. As such, understanding the interaction between biological and physical controls over floodplain meadow water budgets is important to understanding their likely vulnerability or resilience. Floodplain meadow plant communities are highly heterogeneous, leading to patchy landscapes with distinct vegetation. However, it is unclear whether this patchiness in plant distribution is likely to translate into heterogeneous soil-vegetation-atmosphere transfer (SVAT) rates of water and heat, or whether floodplain meadows can reasonably be treated as internally homogeneous in physical terms despite this patchy vegetation. We used a SVAT model, the Soil-Water-Atmosphere-Plants (SWAP) model by J.C. van Dam and co-workers, to explore the controls over the partitioning of water budgets in floodplain meadows. We conducted our research at Yarnton Mead on the River Thames in Oxfordshire, one of the UK's best remaining examples of a floodplain meadow, and which is still managed and farmed in a low-intensity mixed-use manner. We used soil and plant data from our site to parameterise SWAP; we drove the model using in-situ half-hourly meteorological data. We analysed the model's sensitivity to a range of soil and plant parameters - informed by our measurements - in order to assess the effects of different plant communities on SVAT fluxes. We used a novel method to simulate water-table dynamics at the site; the simulated water tables provide a lower boundary condition for SWAP's hydrological submodel. We adjusted the water-table model's parameters so as to represent areas of the mead with contrasting topography, and so different

  7. Control of microbially generated hydrogen sulfide in produced waters

    Energy Technology Data Exchange (ETDEWEB)

    Burger, E.D.; Vance, I.; Gammack, G.F.; Duncan, S.E.

    1995-12-31

    Production of hydrogen sulfide in produced waters due to the activity of sulfate-reducing bacteria (SRB) is a potentially serious problem. The hydrogen sulfide is not only a safety and environmental concern, it also contributes to corrosion, solids formation, a reduction in produced oil and gas values, and limitations on water discharge. Waters produced from seawater-flooded reservoirs typically contain all of the nutrients required to support SRB metabolism. Surface processing facilities provide a favorable environment in which SRB flourish, converting water-borne nutrients into biomass and H{sub 2}S. This paper will present results from a field trial in which a new technology for the biochemical control of SRB metabolism was successfully applied. A slip stream of water downstream of separators on a produced water handling facility was routed through a bioreactor in a side-steam device where microbial growth was allowed to develop fully. This slip stream was then treated with slug doses of two forms of a proprietary, nonbiocidal metabolic modifier. Results indicated that H{sub 2}S production was halted almost immediately and that the residual effect of the treatment lasted for well over one week.

  8. Desalination and water recovery: Control of membrane fouling

    Energy Technology Data Exchange (ETDEWEB)

    Reddy, A.V.R.; Jagan Mohan, D.; Buch, P.R.; Joshi, S.V.; Pushpito Kumar Ghosh [Reverse Osmosis Discipline, Central Salt and Marine Chemicals Research Institute, Bhavnagar, Gujarat (India)]. E-mail: salt@csir.res.in

    2006-07-01

    Ultrafiltration (UF), Nanofiltration (NF) and Reverse Osmosis (RO) technologies are widely used for the production of safe drinking water, and for the recovery of reusable water from various industrial effluent streams. The most commonly encountered phenomenon in these processes, especially in water recovery application, is membrane fouling, and control of membrane fouling is regarded as a significant challenge. Membranes with charged and hydrophilic surfaces are reported to be less susceptible to fouling and often reversible. UF/RO membranes containing negatively charged and/or neutral hydrophilic functional groups on the surface were prepared by surface modification of suitable membranes. The surface modified membranes exhibited separations of 68%-85% for Na{sub 2}SO{sub 4}, 19%-31% for MgSO{sub 4}, 10%-26% for NaCl and 2%-12% for CaCl{sub 2} with water permeation rates of 9-50 l/m{sup 2}-h at the operating pressure of 4 kg/cm{sup 2}. The UF membranes were tested for water recovery from reactive dye effluents containing solutes with molecular sizes in the range of 600-1000 Da along with inorganic solutes. Surface-modified RO membranes were utilised for desalination of brackish water. (author)

  9. Control and Coordination of Frequency Responsive Residential Water Heaters

    Energy Technology Data Exchange (ETDEWEB)

    Williams, Tess L.; Kalsi, Karanjit; Elizondo, Marcelo A.; Marinovici, Laurentiu D.; Pratt, Richard M.

    2016-07-31

    Demand-side frequency control can complement traditional generator controls to maintain the stability of large electric systems in the face of rising uncertainty and variability associated with renewable energy resources. This paper presents a hierarchical frequency-based load control strategy that uses a supervisor to flexibly adjust control gains that a population of end-use loads respond to in a decentralized manner to help meet the NERC BAL-003-1 frequency response standard at both the area level and interconnection level. The load model is calibrated and used to model populations of frequency-responsive water heaters in a PowerWorld simulation of the U.S. Western Interconnection (WECC). The proposed design is implemented and demonstrated on physical water heaters in a laboratory setting. A significant fraction of the required frequency response in the WECC could be supplied by electric water heaters alone at penetration levels of less than 15%, while contributing to NERC requirements at the interconnection and area levels.

  10. Adaptive control model of water resources regulation in the Yellow River

    Institute of Scientific and Technical Information of China (English)

    WEI; Jiahua; WANG; Guangqian; WENG; Wenbin; CAI; Zhiguo; C

    2004-01-01

    According to the principle of procedure control and the characteristic of stochastic of inflow and water demands, this paper deals with the application of adaptive control to a water resources regulation system. The main control objective is to approach the vested target of water resources allocation by controlling the reservoir discharge and water demand. The adaptive control implemented is based on the linear quadratic control approach. Models of water balance, reservoir adjusted model and allocation model are used for the control purposes. The results show the performance of this adaptive scheme and its ability to control the water resources allocation process.

  11. Water hammer prediction and control: the Green's function method

    Institute of Scientific and Technical Information of China (English)

    Li-Jun Xuan; Feng Mao; Jie-Zhi Wu

    2012-01-01

    By Green's function method we show that the water hammer (WH) can be analytically predicted for both laminar and turbulent flows (for the latter,with an eddy viscosity depending solely on the space coordinates),and thus its hazardous effect can be rationally controlled and minimized.To this end,we generalize a laminar water hammer equation of Wang et al.(J.Hydrodynamics,B2,51,1995)to include arbitrary initial condition and variable viscosity,and obtain its solution by Green's function method.The predicted characteristic WH behaviors by the solutions are in excellent agreement with both direct numerical simulation of the original governing equations and,by adjusting the eddy viscosity coefficient,experimentally measured turbulent flow data.Optimal WH control principle is thereby constructed and demonstrated.

  12. Boundary conditions control for a Shallow-Water model

    CERN Document Server

    Kazantsev, Eugene

    2012-01-01

    A variational data assimilation technique was used to estimate optimal discretization of interpolation operators and derivatives in the nodes adjacent to the rigid boundary. Assimilation of artificially generated observational data in the shallow-water model in a square box and assimilation of real observations in the model of the Black sea are discussed. It is shown in both experiments that controlling the discretization of operators near a rigid boundary can bring the model solution closer to observations as in the assimilation window and beyond the window. This type of control allows also to improve climatic variability of the model.

  13. Under Water Wireless Control Using Zigbee For Transmissions Systems

    Directory of Open Access Journals (Sweden)

    Sreenivsa Reddy P,

    2014-07-01

    Full Text Available The aim of this project is to develop under water communication system using the zigbee protocol stack. A robot can be defined as a programmable, self-controlled device consisting of electronic, electrical, or mechanical units. An industrial robot is officially defined by as an automatically controlled, reprogrammable, multipurpose, manipulator, programmable in three or more axes. Robots are especially desirable for certain work functions because, unlike humans, they never get tired. They can endure physical conditions that are uncomfortable or even dangerous; they can operate in airless conditions.

  14. Ultrasonic treatment for microbiological control of water systems

    Energy Technology Data Exchange (ETDEWEB)

    Broekman, S.; Pohlmann, O.; Beardwooden, E. S.; Cordemans de Meulenaer, E. [Ashland Hercules Water Technologies, Krefeld (Germany)

    2010-08-15

    A combination treatment of shear, micro-bubbles, and high-frequency low-power ultrasound introduced via side-stream treatment of industrial water systems has shown excellent results in controlling bacteria and algae; Through the physical, high-stress environment created by ultrasonic waves, sessile and planktonic biological populations, some of which may undergo programmed cell death (PCD), can be controlled. Additionally, the instability and reduction of biofilm have been observed in systems treated by ultrasound and may be attributed to starvation-stress and lack of available cross-linking cations in the biofilm. (authors)

  15. Processes Controlling Water Vapor in the Winter Arctic Tropopause Region

    Science.gov (United States)

    Pfister, Leonhard; Selkirk, Henry B.; Jensen, Eric J.; Padolske, James; Sachse, Glen; Avery, Melody; Schoeberl, Mark R.; Mahoney, Michael J.; Richard, Erik

    2002-01-01

    This work describes transport and thermodynamic processes that control water vapor near the tropopause during the SAGE III-Ozone Loss and Validation Experiment (SOLVE), held during the Arctic 1999/2000 winter season. Aircraft-based water vapor, carbon monoxide, and ozone measurements were analyzed so as to establish how deeply tropospheric air mixes into the Arctic lowermost stratosphere and what the implications are for cloud formation and water vapor removal in this region of the atmosphere. There are three major findings. First, troposphere-to-stratosphere exchange extends into the Arctic stratosphere to about 13 km. Penetration is to similar levels throughout the winter, however, because ozone increases with altitude most rapidly in the early spring, tropospheric air mixes with the highest values of ozone in that season. The effect of this upward mixing is to elevate water vapor mixing ratios significantly above their prevailing stratospheric values of above 5ppmv. Second, the potential for cloud formation in the stratosphere is highest during early spring, with about 20% of the parcels which have ozone values of 300-350 ppbv experiencing ice saturation in a given 10 day period. Third, during early spring, temperatures at the troposphere are cold enough so that 5-10% of parcels experience relative humidities above 100%, even if the water content is as low as 5 ppmv. The implication is that during this period, dynamical processes near the Arctic tropopause can dehydrate air and keep the Arctic tropopause region very dry during early spring.

  16. Physical controls on cold-water coral growth

    Science.gov (United States)

    Floegel, S.; Rueggeberg, A.; Dullo, C.

    2009-04-01

    observation is an Atlantic-wide phenomenon. In areas where coral growth is restricted to some small patches and reefs, or recent mound growth is limited, like in the Gulf of Cadiz or off Mauritania, recent sigma theta values lay outside the envelope of 27.5 ± 0.15 kg m-3. However, it has to be mentioned that corals do not occur everywhere along the European continental margins where sigma theta values are around 27.5 kg m-3. In this case, second order parameters like sedimentation rates, currents, the lack or presence of good settlement substrates, nutrient concentrations, etc. are controlling the coral growth and settlement. Literature Dullo, W.-Chr., Flögel, S., Rüggeberg, A. (in press) Cold-water coral growth in relation to the hydrography of the Celtic and Nordic European Continental Margin. Marine Ecology Progress Series.

  17. INVESTIGATION OF QUANTIFICATION OF FLOOD CONTROL AND WATER UTILIZATION EFFECT OF RAINFALL INFILTRATION FACILITY BY USING WATER BALANCE ANALYSIS MODEL

    OpenAIRE

    文, 勇起; BUN, Yuki

    2013-01-01

    In recent years, many flood damage and drought attributed to urbanization has occurred. At present infiltration facility is suggested for the solution of these problems. Based on this background, the purpose of this study is investigation of quantification of flood control and water utilization effect of rainfall infiltration facility by using water balance analysis model. Key Words : flood control, water utilization , rainfall infiltration facility

  18. Fracture control of ground water flow and water chemistry in a rock aquitard.

    Science.gov (United States)

    Eaton, Timothy T; Anderson, Mary P; Bradbury, Kenneth R

    2007-01-01

    There are few studies on the hydrogeology of sedimentary rock aquitards although they are important controls in regional ground water flow systems. We formulate and test a three-dimensional (3D) conceptual model of ground water flow and hydrochemistry in a fractured sedimentary rock aquitard to show that flow dynamics within the aquitard are more complex than previously believed. Similar conceptual models, based on regional observations and recently emerging principles of mechanical stratigraphy in heterogeneous sedimentary rocks, have previously been applied only to aquifers, but we show that they are potentially applicable to aquitards. The major elements of this conceptual model, which is based on detailed information from two sites in the Maquoketa Formation in southeastern Wisconsin, include orders of magnitude contrast between hydraulic diffusivity (K/S(s)) of fractured zones and relatively intact aquitard rock matrix, laterally extensive bedding-plane fracture zones extending over distances of over 10 km, very low vertical hydraulic conductivity of thick shale-rich intervals of the aquitard, and a vertical hydraulic head profile controlled by a lateral boundary at the aquitard subcrop, where numerous surface water bodies dominate the shallow aquifer system. Results from a 3D numerical flow model based on this conceptual model are consistent with field observations, which did not fit the typical conceptual model of strictly vertical flow through an aquitard. The 3D flow through an aquitard has implications for predicting ground water flow and for planning and protecting water supplies.

  19. 75 FR 43554 - Notice of Lodging of Consent Decree Under the Federal Water Pollution Control Act (“Clean Water...

    Science.gov (United States)

    2010-07-26

    ... of Lodging of Consent Decree Under the Federal Water Pollution Control Act (``Clean Water Act... Water Act, 33 U.S.C. 1311 and 1318, at thirteen of its facilities in Massachusetts by discharging pollutants in storm water associated with construction activity without a permit, failing to timely ]...

  20. 40 CFR 40.140-3 - Federal Water Pollution Control Act.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 1 2010-07-01 2010-07-01 false Federal Water Pollution Control Act. 40... FEDERAL ASSISTANCE RESEARCH AND DEMONSTRATION GRANTS § 40.140-3 Federal Water Pollution Control Act. (a... such safe water and such elimination or control of water pollution for all native villages in the...

  1. Water chemistry controlled aggregation and photo-transformation of silver nanoparticles in environmental waters.

    Science.gov (United States)

    Yin, Yongguang; Yang, Xiaoya; Zhou, Xiaoxia; Wang, Weidong; Yu, Sujuan; Liu, Jingfu; Jiang, Guibin

    2015-08-01

    The inevitable release of engineered silver nanoparticles (AgNPs) into aquatic environments has drawn great concerns about its environmental toxicity and safety. Although aggregation and transformation play crucial roles in the transport and toxicity of AgNPs, how the water chemistry of environmental waters influences the aggregation and transformation of engineered AgNPs is still not well understood. In this study, the aggregation of polyvinylpyrrolidone (PVP) coated AgNPs was investigated in eight typical environmental water samples (with different ionic strengths, hardness, and dissolved organic matter (DOM) concentrations) by using UV-visible spectroscopy and dynamic light scattering. Raman spectroscopy was applied to probe the interaction of DOM with the surface of AgNPs. Further, the photo-transformation and morphology changes of AgNPs in environmental waters were studied by UV-visible spectroscopy, inductively coupled plasma mass spectrometry, and transmission electron microscopy. The results suggested that both electrolytes (especially Ca(2+) and Mg(2+)) and DOM in the surface waters are key parameters for AgNP aggregation, and sunlight could accelerate the morphology change, aggregation, and further sedimentation of AgNPs. This water chemistry controlled aggregation and photo-transformation should have significant environmental impacts on the transport and toxicity of AgNPs in the aquatic environments. Copyright © 2015. Published by Elsevier B.V.

  2. CASE STUDY ON WATER QUALITY CONTROL IN AN AQUAPONIC SYSTEM

    Directory of Open Access Journals (Sweden)

    Radu Mihai Filep

    2016-07-01

    Full Text Available Aquaponic systems are integrated systems that combine fish farming and different types of plants. It involves a dynamic interaction between fish plants and bacteria. Fish and plants are dependent the equilibrium of dissolved nutrients and water quality. Only by striking a balance between dissolved nutrients and water quality we can achieve a large production of plants and healthy fish. Thus, control of water quality in an aquaponic system is essential in order to obtain performance in raising fish and plants. The experiment was conducted in the laboratory of Fisheries and Aquaculture of the Faculty of Animal Science of the University of Agronomic Sciences and Veterinary Medicine of Bucharest within a period of 30 days. The system used for the experiment was designed and developed in the laboratory mentioned above. The plant used for water treatment in the system was basil (Ocimum basilicum. Fish species grown in the system was culture carp (Cyprinus carpio. Indicators measured to assess water quality in the system were: temperature, pH, dissolved oxygen, total ammonia, nitrites, nitrates and phosphates. The values determined pH 7.4-7.6, dissolved oxygen 8-10 mg / l, NH4 0.05-05 mg/ l, NO2 0.1-3.2 mg / l, NO3 0-80 mg / l, 0.02-0.3 mg, PO4 0.02-0.3 mg/l were not too high. In conclusion it was demonstrated that water quality in the aquaponic system studied is propitious to the growth and welfare of fish the registered values are not to be harmful.

  3. Assessment of water quality in the South Indian River Water Control District, Palm Beach County, Florida, 1989-94

    Science.gov (United States)

    Lietz, A.C.

    1996-01-01

    A study was conducted to assess ground-water and surface-water quality in the South Indian River Water Control District in northern Palm Beach County from 1989 to 1994. Contamination of the surficial aquifer system and availability of a potable water supply have become of increasing concern. The study consisted of sampling 11 ground-water wells and 14 surface- water sites for determination of major inorganic constituents and physical characteristics, trace metals, nitrogen and phosphorus species, and synthetic organic compounds. Sodium and chloride concentrations exceeded Florida drinking-water standards in ground water at two wells, dissolved- solids concentrations at five ground-water wells and one surface-water site, and color values at all 11 ground-water wells and all 14 surface-water sites. Other constituents also exhibited concentrations that exceeded drinking-water standards. Cadmium and zinc concentrations exceeded the standards in ground water at one well, and lead concentrations exceeded the standard in ground water at five wells. Nitrogen and phosphorus specie concentrations did not exceed respective drinking-water standards in any ground-water or surface-water samples. Several synthetic organic compounds were detected at or above 50 micrograms per liter in water samples collected from six ground-water wells and three surface-water sites.

  4. Antimicrobial Materials for Advanced Microbial Control in Spacecraft Water Systems

    Science.gov (United States)

    Birmele, Michele; Caro, Janicce; Newsham, Gerard; Roberts, Michael; Morford, Megan; Wheeler, Ray

    2012-01-01

    Microbial detection, identification, and control are essential for the maintenance and preservation of spacecraft water systems. Requirements set by NASA put limitations on the energy, mass, materials, noise, cost, and crew time that can be devoted to microbial control. Efforts are being made to attain real-time detection and identification of microbial contamination in microgravity environments. Research for evaluating technologies for capability enhancement on-orbit is currently focused on the use of adenosine triphosphate (ATP) analysis for detection purposes and polymerase chain reaction (peR) for microbial identification. Additional research is being conducted on how to control for microbial contamination on a continual basis. Existing microbial control methods in spacecraft utilize iodine or ionic silver biocides, physical disinfection, and point-of-use sterilization filters. Although these methods are effective, they require re-dosing due to loss of efficacy, have low human toxicity thresholds, produce poor taste, and consume valuable mass and crew time. Thus, alternative methods for microbial control are needed. This project also explores ultraviolet light-emitting diodes (UV-LEDs), surface passivation methods for maintaining residual biocide levels, and several antimicrobial materials aimed at improving current microbial control techniques, as well as addressing other materials presently under analysis and future directions to be pursued.

  5. Geochemical factors controlling free Cu ion concentrations in river water

    Science.gov (United States)

    Rozan, Tim F.; Benoit, Gaboury

    1999-10-01

    Copper speciation was determined monthly at seven sites on four rivers in southern New England to understand which geochemical factors control free metal ion concentrations in river water. Samples were conventionally filtered (stripping voltammetry (DPASV) was used to quantify natural organic complexation and cathodic stripping square wave voltammetry (CSSWV) to measure directly both Cu sulfide complexes and total EDTA concentrations. The results showed both dissolved organic matter (DOM) and sulfide complexation dominate Cu speciation and control the concentrations of free ion. Free Cu2+ was calculated to be in the subnanomolar range for the majority of the year. Only in the winter months, when concentrations of DOM and metal sulfides complexes were at a minimum were free metal ions directly measurable by DPASV at low nanomolar concentrations. The extent of sulfide complexation appears to be dominated by the size of headwater marshes (upstream sampling sites) and by the amount of sewage treatment plant effluent (downstream sites). DOM complexation was related to the organic matter composition and followed model organic ligands. Indirect evidence suggests variations in river water pH and Ca2+ (metal competition) has only a minor role in Cu complexation. Measured concentrations of total EDTA suggest this synthetic ligand can control Cu speciation in some highly developed watersheds; however, competition from Ni (and possibly Fe) limits the extent of this complexation.

  6. Radio-controlled boat for measuring water velocities and bathymetry

    Science.gov (United States)

    Vidmar, Andrej; Bezak, Nejc; Sečnik, Matej

    2016-04-01

    Radio-controlled boat named "Hi3" was designed and developed in order to facilitate water velocity and bathymetry measurements. The boat is equipped with the SonTek RiverSurveyor M9 instrument that is designed for measuring open channel hydraulics (discharge and bathymetry). Usually channel cross sections measurements are performed either from a bridge or from a vessel. However, these approaches have some limitations such as performing bathymetry measurements close to the hydropower plant turbine or downstream from a hydropower plant gate where bathymetry changes are often the most extreme. Therefore, the radio-controlled boat was designed, built and tested in order overcome these limitations. The boat is made from a surf board and two additional small balance support floats. Additional floats are used to improve stability in fast flowing and turbulent parts of rivers. The boat is powered by two electric motors, steering is achieved with changing the power applied to left and right motor. Furthermore, remotely controlled boat "Hi3" can be powered in two ways, either by a gasoline electric generator or by lithium batteries. Lithium batteries are lighter, quieter, but they operation time is shorter compared to an electrical generator. With the radio-controlled boat "Hi3" we can perform measurements in potentially dangerous areas such as under the lock gates at hydroelectric power plant or near the turbine outflow. Until today, the boat "Hi3" has driven more than 200 km in lakes and rivers, performing various water speed and bathymetry measurements. Moreover, in future development the boat "Hi3" will be upgraded in order to be able to perform measurements automatically. The future plans are to develop and implement the autopilot. With this approach the user will define the route that has to be driven by the boat and the boat will drive the pre-defined route automatically. This will be possible because of the very accurate differential GPS from the Sontek River

  7. Downhole water flow controller for aquifer storage recovery wells

    Energy Technology Data Exchange (ETDEWEB)

    Pyne, R.D.

    1987-09-08

    This patent describes a downhole flow control device for continuous automatic control of water flowing into or out of wells, aquifers and the like through pipe columns. The upper end of the first tubular member is mounted to the pipe column so as to be in fluid communication therewith. The lower end of the first tubular member is substantially closed. A second tubular member is mounted concentrically within and proximate to the first tubular member and has an open upper end and side walls and a substantially closed lower end. First openings are spaced in vertical relationship to the second openings. Third openings are through the second tubular member. The second tubular member is vertically movable with respect to the first tubular member so as to selectively align the third openings with either of the first and second openings. Biasing means are located between the lower ends of the first and second tubular members for normally urging the second tubular member vertically upward with respect to the first tubular member. The biasing means are yieldable upon the introduction of water into the pump column to permit the second tubular member to be vertically displaced relative to the first tubular member to thereby close the third openings with respect to the first or second openings. The third openings align with one of the first and second openings dependent upon the direction of fluid flow within the pipe column.

  8. Photochemical control of the distribution of Venusian water

    Science.gov (United States)

    Parkinson, Christopher D.; Gao, Peter; Esposito, Larry; Yung, Yuk; Bougher, Stephen; Hirtzig, Mathieu

    2015-08-01

    We use the JPL/Caltech 1-D photochemical model to solve continuity diffusion equation for atmospheric constituent abundances and total number density as a function of radial distance from the planet Venus. Photochemistry of the Venus atmosphere from 58 to 112 km is modeled using an updated and expanded chemical scheme (Zhang et al., 2010, 2012), guided by the results of recent observations and we mainly follow these references in our choice of boundary conditions for 40 species. We model water between 10 and 35 ppm at our 58 km lower boundary using an SO2 mixing ratio of 25 ppm as our nominal reference value. We then vary the SO2 mixing ratio at the lower boundary between 5 and 75 ppm holding water mixing ratio of 18 ppm at the lower boundary and finding that it can control the water distribution at higher altitudes. SO2 and H2O can regulate each other via formation of H2SO4. In regions of high mixing ratios of SO2 there exists a "runaway effect" such that SO2 gets oxidized to SO3, which quickly soaks up H2O causing a major depletion of water between 70 and 100 km. Eddy diffusion sensitivity studies performed characterizing variability due to mixing that show less of an effect than varying the lower boundary mixing ratio value. However, calculations using our nominal eddy diffusion profile multiplied and divided by a factor of four can give an order of magnitude maximum difference in the SO2 mixing ratio and a factor of a few difference in the H2O mixing ratio when compared with the respective nominal mixing ratio for these two species. In addition to explaining some of the observed variability in SO2 and H2O on Venus, our work also sheds light on the observations of dark and bright contrasts at the Venus cloud tops observed in an ultraviolet spectrum. Our calculations produce results in agreement with the SOIR Venus Express results of 1 ppm at 70-90 km (Bertaux et al., 2007) by using an SO2 mixing ratio of 25 ppm SO2 and 18 ppm water as our nominal reference

  9. Irrelevant water-management scales for flood prevention, water harvesting and eutrophication control.

    Science.gov (United States)

    Andersson, Jafet; Arheimer, Berit

    2017-04-01

    This poster will give three examples of popular water-management methods, which we discovered had very little effect in practice because they were applied on irrelevant scales. They all use small scale solutions to large scale problems, and did not provide expected results due to neglecting the magnitude of components in the large-scale water budget. 1) Flood prevention: ponds are considered to be able to buffer water discharge in catchments and was suggested as a measure to reduce the 20-years return floods in an exposed areas in Sweden. However, when experimenting with several ponds allocation and size in a computational model, we found out that ponds had to cover 5-10% of the catchment to convert the 20-yr flood into an average flood. Most effective was to allocate one single water body at the catchment outlet, but this would correspond to 95 km2 which is by far too big to be called a pond. 2) Water Harvesting: At small-scale it is designed to increase water availability and agricultural productivity in smallholder agriculture. On field scale, we show that water harvesting decreases runoff by 55% on average in 62 investigated field-scale trials of drainage area ≤ 1ha in sub-Saharan Africa (Andersson et al., 2011). When upscaling, to river basin scale in South Africa (8-1.8×106 km2), using a scenario approach and the SWAT hydrological model we found that all smallholder fields would not significantly alter downstream river discharge (effect on low flows). It shows some potential to increase crop yields but only in some water-scarce areas and conditioned on sufficient fertilizers being available (Andersson et al., 2013). 3) Eutrophication control: Constructed wetlands are supposed to remove nutrients from surface water and therefore 1,574 wetlands were constructed in southern Sweden during the years 1996-2006 as a measure to reduce coastal eutrophication. From our detailed calculations, the gross removal was estimated at 140 tonnes Nitrogen per year and 12

  10. Dynamics of controlled release systems based on water-in-water emulsions: a general theory.

    Science.gov (United States)

    Sagis, Leonard M C

    2008-10-06

    Phase-separated biopolymer solutions, and aqueous dispersions of hydrogel beads, liposomes, polymersomes, aqueous polymer microcapsules, and colloidosomes are all examples of water-in-water emulsions. These systems can be used for encapsulation and controlled release purposes, in for example food or pharmaceutical applications. The stress-deformation behavior of the droplets in these systems is very complex, and affected by mass transfer across the interface. The relaxation time of a deformation of a droplet may depend on interfacial properties such as surface tension, bending rigidity, spontaneous curvature, permeability, and interfacial viscoelasticity. It also depends on bulk viscoelasticity and composition. A non-equilibrium thermodynamic model is developed for the dynamic behavior of these systems, which incorporates all these parameters, and is based on the interfacial transport phenomena (ITP) formalism. The ITP formalism allows us to describe all water-in-water emulsions with one general theory. Phase-separated biopolymer solutions, and dispersions of hydrogel beads, liposomes, polymersomes, polymer microcapsules, and colloidosomes are basically limiting cases of this general theory with respect to bulk and interfacial rheological behavior.

  11. 33 CFR 223.1 - Mississippi River Water Control Management Board.

    Science.gov (United States)

    2010-07-01

    ..., responsibilities and authority of the Mississippi River Water Control Management Board. (b) Applicability. This...) Composition. The Mississippi River Water Control Management Board is a continuing board consisting of the... improving inter-divisional coordination of water control management activities within the Mississippi...

  12. 15 CFR 923.45 - Air and water pollution control requirements.

    Science.gov (United States)

    2010-01-01

    ... 15 Commerce and Foreign Trade 3 2010-01-01 2010-01-01 false Air and water pollution control....45 Air and water pollution control requirements. The program must incorporate, by reference or otherwise, all requirements established by the Federal Water Pollution Control Act, as amended (Clean...

  13. 40 CFR 40.145-2 - Federal Water Pollution Control Act.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 1 2010-07-01 2010-07-01 false Federal Water Pollution Control Act. 40... FEDERAL ASSISTANCE RESEARCH AND DEMONSTRATION GRANTS § 40.145-2 Federal Water Pollution Control Act. (a... or control of acid or other mine water pollution; and (2) That the State shall provide legal...

  14. Microbiological water methods: quality control measures for Federal Clean Water Act and Safe Drinking Water Act regulatory compliance.

    Science.gov (United States)

    Root, Patsy; Hunt, Margo; Fjeld, Karla; Kundrat, Laurie

    2014-01-01

    Quality assurance (QA) and quality control (QC) data are required in order to have confidence in the results from analytical tests and the equipment used to produce those results. Some AOAC water methods include specific QA/QC procedures, frequencies, and acceptance criteria, but these are considered to be the minimum controls needed to perform a microbiological method successfully. Some regulatory programs, such as those at Code of Federal Regulations (CFR), Title 40, Part 136.7 for chemistry methods, require additional QA/QC measures beyond those listed in the method, which can also apply to microbiological methods. Essential QA/QC measures include sterility checks, reagent specificity and sensitivity checks, assessment of each analyst's capabilities, analysis of blind check samples, and evaluation of the presence of laboratory contamination and instrument calibration and checks. The details of these procedures, their performance frequency, and expected results are set out in this report as they apply to microbiological methods. The specific regulatory requirements of CFR Title 40 Part 136.7 for the Clean Water Act, the laboratory certification requirements of CFR Title 40 Part 141 for the Safe Drinking Water Act, and the International Organization for Standardization 17025 accreditation requirements under The NELAC Institute are also discussed.

  15. Can control of soil erosion mitigate water pollution by sediments?

    Science.gov (United States)

    Rickson, R J

    2014-01-15

    The detrimental impact of sediment and associated pollutants on water quality is widely acknowledged, with many watercourses in the UK failing to meet the standard of 'good ecological status'. Catchment sediment budgets show that hill slope erosion processes can be significant sources of waterborne sediment, with rates of erosion likely to increase given predicted future weather patterns. However, linking on-site erosion rates with off-site impacts is complicated because of the limited data on soil erosion rates in the UK and the dynamic nature of the source-pathway-receptor continuum over space and time. Even so, soil erosion control measures are designed to reduce sediment production (source) and mobilisation/transport (pathway) on hill slopes, with consequent mitigation of pollution incidents in watercourses (receptors). The purpose of this paper is to review the scientific evidence of the effectiveness of erosion control measures used in the UK to reduce sediment loads of hill slope origin in watercourses. Although over 73 soil erosion mitigation measures have been identified from the literature, empirical data on erosion control effectiveness are limited. Baseline comparisons for the 18 measures where data do exist reveal erosion control effectiveness is highly variable over time and between study locations. Given the limitations of the evidence base in terms of geographical coverage and duration of monitoring, performance of the different measures cannot be extrapolated to other areas. This uncertainty in effectiveness has implications for implementing erosion/sediment risk reduction policies, where quantified targets are stipulated, as is the case in the EU Freshwater Fish and draft Soil Framework Directives. Also, demonstrating technical effectiveness of erosion control measures alone will not encourage uptake by land managers: quantifying the costs and benefits of adopting erosion mitigation is equally important, but these are uncertain and difficult to

  16. Boron nitride nanosheet coatings with controllable water repellency.

    Science.gov (United States)

    Pakdel, Amir; Zhi, Chunyi; Bando, Yoshio; Nakayama, Tomonobu; Golberg, Dmitri

    2011-08-23

    The growth, structure, and properties of two-dimensional boron nitride (BN) nanostructures synthesized by a thermal chemical vapor deposition method have been systematically investigated. Most of the BN nanosheets (BNNSs) were less than 5 nm in thickness, and their purity was confirmed by X-ray energy dispersive spectroscopy, X-ray photoelectron spectroscopy, electron energy loss spectroscopy, and Raman spectroscopy. The effects of the process variables on the morphology and roughness of the coatings were studied using atomic force microscopy and scanning electron microscopy. A smooth BN coating was obtained at 900 °C, while compact BNNS coatings composed of partially vertically aligned nanosheets could be achieved at 1000 °C and higher temperatures. These nanosheets were mostly separated and exhibited high surface area especially at higher synthesis temperatures. The nonwetting properties of the BNNS coatings were independent of the water pH and were examined by contact angle goniometry. The present results enable a convenient growth of pure BNNS coatings with controllable levels of water repellency, ranging from partial hydrophilicity to superhydrophobicity with contact angles exceeding 150°. © 2011 American Chemical Society

  17. Biological stability of drinking water: Controlling factors, methods, and challenges

    NARCIS (Netherlands)

    Prest, E.I.E.D.; Hammes, F.; Van Loosdrecht, M.C.M.; Vrouwenvelder, J.S.

    2016-01-01

    Biological stability of drinking water refers to the concept of providing consumers with drinking water of same microbial quality at the tap as produced at the water treatment facility. However, uncontrolled growth of bacteria can occur during distribution in water mains and premise plumbing, and ca

  18. Biological stability of drinking water: Controlling factors, methods, and challenges

    NARCIS (Netherlands)

    Prest, E.I.E.D.; Hammes, F.; Van Loosdrecht, M.C.M.; Vrouwenvelder, J.S.

    2016-01-01

    Biological stability of drinking water refers to the concept of providing consumers with drinking water of same microbial quality at the tap as produced at the water treatment facility. However, uncontrolled growth of bacteria can occur during distribution in water mains and premise plumbing, and ca

  19. Water Pollution Scrubber Activity Simulates Pollution Control Devices.

    Science.gov (United States)

    Kennedy, Edward C., III; Waggoner, Todd C.

    2003-01-01

    A laboratory activity caused students to think actively about water pollution. The students realized that it would be easier to keep water clean than to remove pollutants. They created a water scrubbing system allowing them to pour water in one end and have it emerge clean at the other end. (JOW)

  20. Water Pollution Scrubber Activity Simulates Pollution Control Devices.

    Science.gov (United States)

    Kennedy, Edward C., III; Waggoner, Todd C.

    2003-01-01

    A laboratory activity caused students to think actively about water pollution. The students realized that it would be easier to keep water clean than to remove pollutants. They created a water scrubbing system allowing them to pour water in one end and have it emerge clean at the other end. (JOW)

  1. Biological stability of drinking water: Controlling factors, methods, and challenges

    NARCIS (Netherlands)

    Prest, E.I.E.D.; Hammes, F.; Van Loosdrecht, M.C.M.; Vrouwenvelder, J.S.

    2016-01-01

    Biological stability of drinking water refers to the concept of providing consumers with drinking water of same microbial quality at the tap as produced at the water treatment facility. However, uncontrolled growth of bacteria can occur during distribution in water mains and premise plumbing, and

  2. From Flood Control to Water Management: A Journey of Bangladesh towards Integrated Water Resources Management

    Directory of Open Access Journals (Sweden)

    Animesh K. Gain

    2017-01-01

    Full Text Available Integrated Water Resources Management (IWRM is considered as a practical approach in solving water-related problems, which are socio-ecologically complex in nature. Bangladesh has also embraced the IWRM approach against its earlier attempt to flood control. In this paper, we evaluate the current status of IWRM in Bangladesh through the lens of policy shifts, institutional transitions and project transformations using seven key dimensions of IWRM. Looking at IWRM from such perspectives is lacking in current literature. A thorough review of policy shifts suggests that all the key dimensions of IWRM are “highly reflected” in the current policy documents. The dimension of “integrated management” is “highly reflected” in both institutional transition and project-level transformation. Most other dimensions are also recognised at both institutional and project levels. However, such reflections gradually weaken as we move from policies to institutions to projects. Despite catchment being considered as a spatial unit of water management at both institutional and project levels, transboundary basin planning is yet to be accomplished. The participation of local people is highly promoted in various recent projects. However, equity and social issues have received less attention at project level, although it has significant potential for supporting some of the key determinants of adaptive capacity. Thus, the IWRM dimensions are in general reflected in recent policies, institutional reforms and project formulation in Bangladesh. However, to solve the complex water-problems, basin scale management through transboundary cooperation and equity and social issues need to be implemented at institutional and project levels.

  3. Particle Size Controls on Water Adsorption and Condensation Regimes at Mineral Surfaces

    OpenAIRE

    Merve Yeşilbaş; Jean-François Boily

    2016-01-01

    Atmospheric water vapour interacting with hydrophilic mineral surfaces can produce water films of various thicknesses and structures. In this work we show that mineral particle size controls water loadings achieved by water vapour deposition on 21 contrasting mineral samples exposed to atmospheres of up to ~16 Torr water (70% relative humidity at 25 °C). Submicrometer-sized particles hosted up to ~5 monolayers of water, while micrometer-sized particles up to several thousand monolayers. All f...

  4. [Operational control of water fluoridation in Niterói, Rio de Janeiro, Brazil].

    Science.gov (United States)

    Maia, Lucianne Cople; Valença, Ana Maria Gondim; Soares, Eduardo Lúcio; Cury, Jaime Aparecido

    2003-01-01

    The aim of this study was to evaluate the operational control of water fluoridation at the city water supply plant in Niterói, Rio de Janeiro, Brazil, from January to December 2000. The water treatment supervisor filled out a questionnaire on the control of water fluoridation. In addition, water samples were collected every two weeks for fluoride analysis before and after treatment. Samples were analyzed by an independent laboratory using an ion-specific electrode. According to the water treatment supervisor, the entire process for controlling fluoride concentration in the water was rigorous and complied with Brazilian guidelines, but according to testing, 96% of samples were inadequate in terms of risks/benefits of fluoride use from water. The information obtained from the plant supervisor and the test data were thus mutually inconsistent. Based on these data, an independent water fluoride concentration control program is needed to ensure the benefits of dental caries prevention for the population.

  5. Study on chemical control indicators for circulating cooling systems water chemistry at power plants

    OpenAIRE

    Кишневский, Виктор Афанасьевич; Чиченин, Вадим Валентинович

    2014-01-01

    An analysis of applied stability indices, used for water chemistry control of circulating cooling systems at TPP and NPP is given in the paper.The spectrum of controlled indicators of circulating and make-up water during long-term operation of various water chemistries on scale models of circulating cooling systems at TPP and NPP is investigated.The results of chemical control of water chemistry with dosing mineral acid to make-up water and acrylic water chemistry without dosing mineral acid ...

  6. Water-Saving and High-Yielding Irrigation for Lowland Rice by Controlling Limiting Values of Soil Water Potential

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The present study investigated whether an irrigation system could be established to save water and increase grain yield to enhance water productivity by proper water management at the field level in irrigated lowland rice (Oryza sativa L.). Using two field-grown rice cultivars, two irrigation systems; conventional irrigation and water-saving irrigation, were conducted.In the water-saving irrigation system, limiting values of soil water potential related to specific growth stages were proposed as irrigation indices. Compared with conventional irrigation where drainage was in mid-season and flooded at other times,the water-saving irrigation increased grain yield by 7.4% to 11.3%, reduced irrigation water by 24.5% to 29.2%, and increased water productivity (grain yield per cubic meter of irrigation water) by 43.1% to 50.3%. The water-saving irrigation significantly increased harvest index, improved milling and appearance qualities, elevated zeatin +zeatin riboside concentrations in root bleedings and enhanced activities of sucrose synthase, adenosine diphosphate glucose pyrophosphorylase, starch synthase and starch branching enzyme in grains. Our results indicate that water-saving irrigation by controlling limiting values of soil water potential related to specific growth stages can enhance physiological activities of roots and grains,reduce water input, and increase grain yield.

  7. Supplement Analysis for the Transmission System Vegetation Management Program FEIS (DOE/EIS-0285/SA-109) - (Santiam-Alvey # 1 and #2 access road and structure clearing)

    Energy Technology Data Exchange (ETDEWEB)

    Barndt, Shawn L. [Bonneville Power Administration (BPA), Portland, OR (United States)

    2002-09-09

    Tall-growing vegetation that is currently or will soon be a hazard to the line will be removed. Vegetation that will grow tall will be selectively eliminated before it reaches a height or density to begin competing with low-growing species. Cut-stump or follow-up herbicide treatments on re-sprouting-type species will be carried out to ensure that the roots are killed. Desirable low-growing plants will not be disturbed. Only selective vegetation control methods that have little potential to harm non-target vegetation will be used.

  8. Recovery Act: Water Heater ZigBee Open Standard Wireless Controller

    Energy Technology Data Exchange (ETDEWEB)

    Butler, William P. [Emerson Electric Co., St. Louis, MO (United States); Buescher, Tom [Emerson Electric Co., St. Louis, MO (United States)

    2014-04-30

    The objective of Emerson's Water Heater ZigBee Open Standard Wireless Controller is to support the DOE's AARA priority for Clean, Secure Energy by designing a water heater control that levels out residential and small business peak electricity demand through thermal energy storage in the water heater tank.

  9. Economics of Selected Water Control Technologies and their ...

    African Journals Online (AJOL)

    management, water for multiple use systems and all relevant aspects of ... would add to our understanding of adoption decisions (Doss, 2006). ... Methodology .... International Water Management Institute (IWMI) with support from United States.

  10. Polymer gels for water control: NMR and CT scan studies

    NARCIS (Netherlands)

    Al-Muntasheri, G.A.

    2008-01-01

    As oil and gas reservoirs mature, larger volumes of water are produced. These large volumes of produced water need to be separated, processed, treated and re-injected into the reservoir. All of these processes impose extra costs to the hydrocarbon production. Water rates can increase until productio

  11. Suspended sediment control and water quality conservation through riparian vegetation:

    Science.gov (United States)

    Pavanelli, D.; Cavazza, C.; Correggiari, S.

    2009-04-01

    Soil erosion and Suspended Sediment River are strongly related in the Apennines catchments which are generally characterised by a clayey lithology and impermeable soils and extensive and severe erosion and slope stability problems. In fact the suspended sediment yield represents one of the most reliable tools to assess real basin soil loss (Pavanelli and Pagliarani, 2002; Pavanelli and Rigotti, 2007) from the surface rain erosive features in a mountain watershed, as rills and interrills erosion, gullies, bad-lands (calanchi basins). Suspended sediment yield is known to imply several detrimental consequences: soil losses from agricultural land, worsening of the quality of the water, clogging of water supply filters and reservoir siltation. In addition, suspended sediment yield is also one of the main vector for pollutants and nutrients: various studies have already proved how nitrogen content has been constantly rising in aquifers and surface waters [Böhlke and Denver, 1995]. Finer particles and their aggregates have been proved to be the preferential vehicle for particulate nitrogen [Droppo et al., 1997; Ongley et al., 1992]. In one research [Pavanelli and al. 2006] four Apennines torrents (Gaiana, Sillaro, Savena and Lavino) with mountain basins ranging from 8.7 to 139 Km2 were monitored via automatic sampling devices, the samples of water collected were analysed to characterise suspended solids in terms of their grain size distribution and total nitrogen with respect to the source of eroded area in the catchment. Preliminary results [Pavanelli and al. 2007] seem to show the existence of a direct relationship between nitrogen concentration and finer particle concentration (position within the catchment and the availability of suspended particles. The results seem to indicate hillsides as main sources of suspended sediment to the torrents monitored. The problem of controlling the river suspended sediment concentration can be tackled by increasing the riparian

  12. Drinking water quality: stakes of control and sanitation in the town of ...

    African Journals Online (AJOL)

    Drinking water quality: stakes of control and sanitation in the town of Dschang - Cameroon. ... used 728 alternative points for water assessment (705 wells and 23 springs), ... For the wastewater drainage and treatment, no device is constructed.

  13. The Model and Control Methods of Access to Information and Technology Resources of Automated Control Systems in Water Supply Industry

    Science.gov (United States)

    Rytov, M. Yu; Spichyack, S. A.; Fedorov, V. P.; Petreshin, D. I.

    2017-01-01

    The paper describes a formalized control model of access to information and technological resources of automated control systems at water supply enterprises. The given model considers the availability of various communication links with information systems and technological equipment. There are also studied control methods of access to information and technological resources of automated control systems at water supply enterprises. On the basis of the formalized control model and appropriate methods there was developed a software-hardware complex for rapid access to information and technological resources of automated control systems, which contains an administrator’s automated workplace and ultimate users.

  14. Aquaporins: highly regulated channels controlling plant water relations.

    Science.gov (United States)

    Chaumont, François; Tyerman, Stephen D

    2014-04-01

    Plant growth and development are dependent on tight regulation of water movement. Water diffusion across cell membranes is facilitated by aquaporins that provide plants with the means to rapidly and reversibly modify water permeability. This is done by changing aquaporin density and activity in the membrane, including posttranslational modifications and protein interaction that act on their trafficking and gating. At the whole organ level aquaporins modify water conductance and gradients at key "gatekeeper" cell layers that impact on whole plant water flow and plant water potential. In this way they may act in concert with stomatal regulation to determine the degree of isohydry/anisohydry. Molecular, physiological, and biophysical approaches have demonstrated that variations in root and leaf hydraulic conductivity can be accounted for by aquaporins but this must be integrated with anatomical considerations. This Update integrates these data and emphasizes the central role played by aquaporins in regulating plant water relations.

  15. Control and Central Monitoring of a Large Multipurpose Water Delivery System

    OpenAIRE

    Rijo, Manuel; Prado, Miguel; Paulo, Victor

    2001-01-01

    This paper presents the first approach to the centralized SCADA system and automation of the Multipurpose Alqueva Project (MAP). MAP is located in the South of Portugal, mainly in the Guadiana River Basin. It will transfer water to the Sado River Basin. The MAP water delivery control system will guarantee on-line water demands and minimizes water operational losses and energy costs due to pumping. A general modular and hierarchical configuration for the control system is presented. Each compo...

  16. Soft-Sensing Method of Water Temperature Measurement for Controlled Cooling System

    Institute of Scientific and Technical Information of China (English)

    CAI Xiao-hui; ZHANG Dian-hua; WANG Guo-dong; LIU Xiang-hua; FAN Lei

    2003-01-01

    Aiming at the water temperature measuring problem for controlled cooling system of rolling plant, a new water temperature measuring method based on soft-sensing method with a water temperature model of on-line self correction parameter was built. A water temperature compensation factor model was also built to improve coiling temperature control precision. It was proved that the model meets production requirements. The soft-sensing technique has extensive applications in the field of metal forming.

  17. Institutions, technology and water control; water users associations and irrigation management reform in two large-scale systems in India

    NARCIS (Netherlands)

    Narain, V.

    2003-01-01

    Few studies of resource management have paid as much attention or intelligently surveyed the operational aspects of Water User Associations (WUAs) as Institutions, Technology and Water Control. The implementation of WUAs policies, argues this pioneering study, is shaped by the aspirations of its use

  18. Pollution source control by water utilities – characterisation and implications for water management: research results from England and Wales

    NARCIS (Netherlands)

    Spiller, M.; McIntosh, B.S.; Seaton, R.A.F.; Jeffrey, P.

    2013-01-01

    The treatment of agriculturally polluted water to potable standards is costly for water companies. Changes in agricultural practice can reduce these costs while also meeting the objectives of European Union (EU) environmental legislation. In this paper, the uptake of source control interventions (SC

  19. Pollution source control by water utilities – characterisation and implications for water management: research results from England and Wales

    NARCIS (Netherlands)

    Spiller, M.; McIntosh, B.S.; Seaton, R.A.F.; Jeffrey, P.

    2013-01-01

    The treatment of agriculturally polluted water to potable standards is costly for water companies. Changes in agricultural practice can reduce these costs while also meeting the objectives of European Union (EU) environmental legislation. In this paper, the uptake of source control interventions

  20. [Discussion on water conservancy projects and schistosomiasis control in Poyang Lake area].

    Science.gov (United States)

    Liu, Dao-Nan

    2013-02-01

    According to the schistosomiasis endemic situation in the Poyang Lake area, this paper analyzes the relationship between the water conservancy projects and schistosomiasis control, and reviews and discusses the effects of the Water Level Control Project of Poyang Lake, the Lake Dike Slope Hardening Project, and the Lifting Delta and Descending Beach Project on Oncomelania snail control.

  1. Model Predictive Control for Operational Water Management: A Case Study of the Dutch Water System

    NARCIS (Netherlands)

    Tian, X.

    2015-01-01

    Water is needed everywhere to satisfy domestic, agricultural and industrial water demands, to maintain navigation systems, and to preserve healthy and sustainable ecosystems. In order to protect us from floods and to reallocate water resources in a man-made environment, the 'hardware', water-related

  2. Model Predictive Control for Operational Water Management: A Case Study of the Dutch Water System

    NARCIS (Netherlands)

    Tian, X.

    2015-01-01

    Water is needed everywhere to satisfy domestic, agricultural and industrial water demands, to maintain navigation systems, and to preserve healthy and sustainable ecosystems. In order to protect us from floods and to reallocate water resources in a man-made environment, the 'hardware', water-related

  3. Sustainable water use in cities: water tariff as tool for consumption control; El uso sostenible del agua en nucleos urbanos: las tarifas como herramienta de control del consumo

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez Garcia, V.E.; Blanco Jimenez, F.J.

    2012-07-01

    The Water Framework Directive requires the adoption of a tariff system that recovers the costs of water resources and the establishment of national water-pricing policies that help to achieve a sustainable water use. Water rates (tariffs) should be used as an auxiliary tool for consumption control, seeking for efficiency and a sustainable resource use. In this research, we studied the characteristics of the existing rates in seven Spanish cities, analyzing the behavior of consumption of domestic water during the period 2003-2010, in order to check whether the current Spanish rates conforms to the state of resources and the objectives of the Directive. The main conclusion of our work is that the current system has lost its effectiveness as a control consumption tool, making it necessary to rethink the pricing policy and a new tariff system in Spain. (Author)

  4. Water outlet control mechanism for fuel cell system operation in variable gravity environments

    Science.gov (United States)

    Vasquez, Arturo (Inventor); McCurdy, Kerri L. (Inventor); Bradley, Karla F. (Inventor)

    2007-01-01

    A self-regulated water separator provides centrifugal separation of fuel cell product water from oxidant gas. The system uses the flow energy of the fuel cell's two-phase water and oxidant flow stream and a regulated ejector or other reactant circulation pump providing the two-phase fluid flow. The system further uses a means of controlling the water outlet flow rate away from the water separator that uses both the ejector's or reactant pump's supply pressure and a compressibility sensor to provide overall control of separated water flow either back to the separator or away from the separator.

  5. Water Rights Arenas in the Andes: Upscaling Networks to Strengthen Local Water Control

    Directory of Open Access Journals (Sweden)

    Rutgerd Boelens

    2008-06-01

    Full Text Available The threats that Andean water user collectives face are ever-growing in a globalising society. Water is power and engenders social struggle. In the Andean region, water rights struggles involve not only disputes over the access to water, infrastructure and related resources, but also over the contents of water rules and rights, the recognition of legitimate authority, and the discourses that are mobilised to sustain water governance structures and rights orders. While open and large-scale water battles such as Bolivia’s 'Water Wars' or nationwide mobilisations in Ecuador get the most public attention, low-profile and more localised water rights encounters, ingrained in local territories, are far more widespread and have an enormous impact on the Andean waterscapes. This paper highlights both water arenas and the ways they operate between the legal and the extralegal. It shows how local collectives build on their own water rights foundations to manage internal water affairs but which simultaneously offer an important home-base for strategising wider water defence manoeuvres. Hand-in-hand with inwardly reinforcing their rights bases, water user groups aim for horizontal and vertical linkages thereby creating strategic alliances. Sheltering an internal school for rights and identity development, reflection and organisation, these local community foundations, through open and subsurface linkages and fluxes, provide the groundwork for upscaling their water rights defence networks to national and transnational arenas.

  6. Shrinking, growing, and bursting: microfluidic equilibrium control of water-in-water droplets.

    Science.gov (United States)

    Moon, Byeong-Ui; Hwang, Dae Kun; Tsai, Scott S H

    2016-07-05

    We demonstrate the dynamic control of aqueous two phase system (ATPS) droplets in shrinking, growing, and dissolving conditions. The ATPS droplets are formed passively in a flow focusing microfluidic channel, where the dextran-rich (DEX) and polyethylene glycol-rich (PEG) solutions are introduced as disperse and continuous phases, respectively. To vary the ATPS equilibrium condition, we infuse into a secondary inlet the PEG phase from a different polymer concentration ATPS. We find that the resulting alteration of the continuous PEG phase can cause droplets to shrink or grow by approximately 45 and 30%, respectively. This volume change is due to water exchange between the disperse DEX and continuous PEG phases, as the system tends towards new equilibria. We also develop a simple model, based on the ATPS binodal curve and tie lines, that predicts the amount of droplet shrinkage or growth, based on the change in the continuous phase PEG concentration. We observe a good agreement between our experimental results and the model. Additionally, we find that when the continuous phase PEG concentration is reduced such that PEG and DEX phases no longer phase separate, the ATPS droplets are dissolved into the continuous phase. We apply this method to controllably release encapsulated microparticles and cells, and we find that their release occurs within 10 seconds. Our approach uses the dynamic equilibrium of ATPS to control droplet size along the microfluidic channel. By modulating the ATPS equilibrium, we are able to shrink, grow, and dissolve ATPS droplets in situ. We anticipate that this approach may find utility in many biomedical settings, for example, in drug and cell delivery and release applications.

  7. ENVIRONMENTAL CONTROL OF NANNOPLANKTON AND FORAMINIFERA ASSEMBLAGES IN MADURA WATERS

    Directory of Open Access Journals (Sweden)

    Vijaya Isnaniawardhani

    2017-07-01

    Full Text Available Nannoplankton is widely used for determining age of sediments following the other microorganism foraminifera since the late 1960s; and it was started being used for marine geography study in the year of 1984. This topic interests to be done in Indonesia as one of the tropic region. The research covered a study about environment using nannoplankton and it is compared with the same study using foraminifera. Methods of the study include: (1 collecting secondary data and samples; (2 collecting field data record; (3 laboratory analyses upon sediment samples to determine the content of nannoplankton and foraminifera (micropaleontology analyses, the texture and composition of minerals (by means of grain size, petrology megascopic and microscopic analyses (4 intergrating all of the analyses result. Madura waters can be divided into four zones, among all : (I inner shelf (water depth less than 30 m in Madura Strait, (II inner shelf in open marine north of Madura, (III outer shelf (water depth 30 to 80 m in Madura Strait, and (IV outer shelf in open marine north of Madura. Inner shelf in the Madura Strait (Zone I is characterized by less than 1% sediment of nannoplankton (are made up of Gephyrocapsa oceanica; rare assemblages of benthic foraminifera only (Ammonia spp., arenaceous carbonate test taxa such as : Ammobaculites spp., Textularia agglutinans, Haplophragmoides spp., and milliolidae. Inner shelf open marine north of Madura (Zone II yielded few nannoplankton assemblages, dominated by Gephyrocapsa oceanica with low number of Emiliania huxleyi, Helicosphaera carteri, H. pavimentum, H. walichii and Pontosphaera spp; common foraminifera assemblages consist of rare planktic Globigerinoides ruber, G. trilobus sacculiferus, G. conglobatus with one or two dominant benthic (Elphidium spp, Ammonia spp., Pseudorotalia spp., Asterorotalia spp.. Outer shelf of Madura Strait (Zone III assigned by common nannoplankton assemblages, dominated by Gephyrocapsa

  8. Operation and Maintenance of Water Pollution Control Facilities: A WPCF White Paper.

    Science.gov (United States)

    Hill, William R.; And Others

    1979-01-01

    Presented are the recommendations of the Water Pollution Control Federation for operation and maintenance consideration during the planning design, construction, and operation of wastewater treatment facilities. (CS)

  9. Operation and Maintenance of Water Pollution Control Facilities: A WPCF White Paper.

    Science.gov (United States)

    Hill, William R.; And Others

    1979-01-01

    Presented are the recommendations of the Water Pollution Control Federation for operation and maintenance consideration during the planning design, construction, and operation of wastewater treatment facilities. (CS)

  10. CONTROLLING EXCESS STORM WATER RUNOFF WITH TRADABLE CREDITS

    Science.gov (United States)

    Development that increases the impervious surface in a watershed causes excess storm water runoff (SWR) that has been identified as a major contributor to stream and riparian habitat degradation. Reduction of storm water runoff can be achieved through establishment of a number of...

  11. Topographic, edaphic, and vegetative controls on plant-available water

    Science.gov (United States)

    Dymond, Salli F.; Bradford, John B.; Bolstad, Paul V.; Kolka, Randall K.; Sebestyen, Stephen D.; DeSutter, Thomas S.

    2017-01-01

    Soil moisture varies within landscapes in response to vegetative, physiographic, and climatic drivers, which makes quantifying soil moisture over time and space difficult. Nevertheless, understanding soil moisture dynamics for different ecosystems is critical, as the amount of water in a soil determines a myriad ecosystem services and processes such as net primary productivity, runoff, microbial decomposition, and soil fertility. We investigated the patterns and variability in in situ soil moisture measurements converted to plant-available water across time and space under different vegetative cover types and topographic positions at the Marcell Experimental Forest (Minnesota, USA). From 0 – 228.6 cm soil depth, plant-available water was significantly higher under the hardwoods (12%), followed by the aspen (8%) and red pine (5%) cover types. Across the same soil depth, toeslopes were wetter (mean plant-available water = 10%) than ridges and backslopes (mean plant-available water was 8%), although these differences were not statistically significant (p plant-available water and that topography was not significantly related to plant-available water within this low-relief landscape. Additionally, during the three-year monitoring period, red pine and quaking aspen sites experienced plant-available water levels that may be considered limiting to plant growth and function. Given that increasing temperatures and more erratic precipitation patterns associated with climate change may result in decreased soil moisture in this region, these species may be sensitive and vulnerable to future shifts in climate.

  12. Emission Control in River Network System of the Taihu Basin for Water Quality Assurance of Water Environmentally Sensitive Areas

    Directory of Open Access Journals (Sweden)

    Xiao Wang

    2017-02-01

    Full Text Available As pollution incidents frequently occurred in the functional water areas of the Taihu Basin, Yangtze Delta, effective emission control to guarantee water quality in the Taihu Basin became the priority for environmental management. In this study, a new total emission control (TEC method was proposed with an emphasis on the concept of water environmentally sensitive areas (WESAs. This method was verified in Wujiang District and the techniques can be concluded in three steps: (1 a 1-D mathematical model for the study area was established and the model was calibrated using field measurement data; (2 based on an analysis of administrative planning and regulations, WESAs were identified as the main controlling objectives for emission control calculations. The weighting coefficient of local pollution sources was investigated to discuss the effectiveness of TEC on water quality improvement at WESAs; and (3 applying the river network mathematical model, water quality along the river segments was simulated under different pollution control plans. The results proved the effectiveness of TEC in the study area and indicated that a 14.6% reduction in the total amount of ammonia-nitrogen (NH3-N, as well as a 31.1% reduction in the total amount of chemical oxygen demand (CODcr, was essential in order to meet the water quality standard in the WESAs.

  13. Control of health risks in drinking water through point-of-use systems

    Institute of Scientific and Technical Information of China (English)

    LIU RuiPing; QU JiuHui

    2009-01-01

    The control of health risks and the provision of safe drinking water have received great concern in the research field of the science and technologies of drinking water purification. The chemicals, microorganisms, and nano-materials in drinking water exhibit the basic characteristics of low-dosage, complexity, and hard-to-control, and promote potential health risks during the treatment, distribution, and storing of drinking water. The establishment of point-of-use (POU) systems is required for the control of health risks in drinking water according to these practical requirements. This study proposed the philosophy of point-of-use (POU) systems which aimed to control the health risks in drinking water, and introduced several key unit processes. Based on the idea above, the POU systems for health risks control have been developed and successfully used in the Olympic Village and its core areas during the period of 2008 Beijing Olympic Games.

  14. Measurement and control of water content of organic solvents

    Energy Technology Data Exchange (ETDEWEB)

    Goderis, H.L.; Fouwe, B.L.; Van Cauwenbergh, S.M.; Tobback, P.P.

    1986-06-01

    An isotopic dilution procedure is described for the quantitative determination of the solubility of water in organic solvents as a function of the relative humidity at which the sample is equilibrated. /sup 3/H/sub 2/O is used as a tracer, and the relative humidity conditions are realized by incubation of the organic solvent above a saturated salt solution having a known water activity. The technique is applicable independent of the concentration range of water present, the minimum amount of moisture being only limited by the concentration of the tritium label used. Solubility isotherms of water in hydrocarbon solvents such as n-hexane are sigmoidal in shape, reflecting cooperative effects in the solubilization of water molecules at the higher relative humidity portion of the curve. Solubility increases with increasing temperature.

  15. Processes Controlling Water Vapor in the Winter Arctic Stratospheric Middleworld

    Science.gov (United States)

    Pfister, Leonhard; Selkirk, Henry; Jensen, Eric; Sachse, Glenn; Podolske, James; Schoeberl, Mark; Browell, Edward; Ismail, Syed; Hipskind, R. Stephen (Technical Monitor)

    2000-01-01

    Water vapor in the winter arctic stratospheric middleworld is import-an: for two reasons: (1) the arctic middleworld is a source of air for the upper Troposphere because of the generally downward motion, and thus its water vapor content helps determine upper tropospheric water, a critical part of the earth's radiation budget; and (2) under appropriate conditions, relative humidities will be large, even to the point of stratospheric cirrus cloud formation, leading to the production of active chlorine species that could destroy ozone. On a number of occasions during SOLVE, clouds were observed in the stratospheric middleworld by the DC-8 aircraft. These tended to coincide with regions of low temperatures, though some cases suggest water vapor enhancements due to troposphere-to-stratosphere transport. The goal of this work is to understand the importance of processes in and at the edge of the arctic stratospheric middleworld in determining water vapor at these levels. Specifically, is water vapor at these levels determined largely by the descent of air from above, or are clouds both within and at the edge of the stratospheric middleworld potentially important? How important is troposphere-to-stratosphere transport of air in determining stratospheric middleworld water vapor content? To this end, we will first examine the minimum saturation mixing ratios along theta/EPV tubes during the SOLVE winter and compare these with DC-8 water vapor observations. This will be a rough indicator of how high relative humidities can get, and the likelihood of cirrus cloud formation in various parts of the stratospheric middleworld. We will then examine saturation mixing ratios along both diabatic and adiabatic trajectories, comparing these values with actual aircraft water vapor observations, both in situ and remote. Finally, we will attempt to actually predict water vapor using minimum saturation mixing ratios along trajectories, cloud injection (derived from satellite imagery) along

  16. Shedding the waters : institutional change and water control in the Lerma-Chapala Basin, Mexico

    NARCIS (Netherlands)

    Wester, P.

    2008-01-01

    Water resources development has led to water overexploitation in many river basins around the world. This is clearly the case in the Lerma-Chapala Basin in central Mexico, where excessive surface water use nearly resulted in the drying up of Lake Chapala, one of the world’s largest shallow lakes. It

  17. Shedding the waters : institutional change and water control in the Lerma-Chapala Basin, Mexico

    NARCIS (Netherlands)

    Wester, P.

    2008-01-01

    Water resources development has led to water overexploitation in many river basins around the world. This is clearly the case in the Lerma-Chapala Basin in central Mexico, where excessive surface water use nearly resulted in the drying up of Lake Chapala, one of the world’s largest shallow lakes. It

  18. Gulf of Maine - Control Points Used to Validate the Accuracies of the Interpolated Water Density Rasters

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This feature dataset contains the control points used to validate the accuracies of the interpolated water density rasters for the Gulf of Maine. These control...

  19. Endotoxin contamination and control in surface water sources and a drinking water treatment plant in Beijing, China.

    Science.gov (United States)

    Can, Zhang; Wenjun, Liu; Wen, Sun; Minglu, Zhang; Lingjia, Qian; Cuiping, Li; Fang, Tian

    2013-07-01

    In this paper, endotoxin contamination was determined in treated water following each unit of a drinking water treatment plant (WTP) in Beijing, China and its source water (SW) from a long water diversion channel (Shijiazhuang-Beijing) originating from four reservoirs in Hebei province, China. The total-endotoxin activities in SW ranged from 21 to 41 EU/ml at five selected cross sections of the diversion channel. The total-endotoxin in raw water of the WTP ranged from 11 to 16 EU/ml due to dilution and pretreatment during water transportation from Tuancheng Lake to the WTP, and finished water of the WTP ranged from 4 to 10 EU/ml, showing a 49% decrease following the full-scale treatment process at the WTP. Compared with the 31% removal of free-endotoxin, the WTP removed up to 71% of bound-endotoxin in raw water. The traditional treatment processes (coagulation, sedimentation and filtration) in the WTP removed substantial amounts of total-endotoxin (up to 63%), while endotoxin activities increased after granular activated carbon (GAC) adsorption and chlorination. The total-endotoxin in the actual water was composed of free-endotoxin and bound-endotoxin (endotoxin aggregates, bacteria-bound endotoxins and particle-attached endotoxins). The endotoxin aggregates, bacteria-bound endotoxins and particle-attached endotoxins co-exist as suspended particles in water, and only the bacteria-bound endotoxins were correlated with bacterial cells suspended in water. The particle distribution of endotoxin aggregates in ultrapure water was also tested and the results showed that the majority (64-89%) of endotoxin aggregates had diameters endotoxin contamination and control in treated water following each unit of the WTP processes and its SW from reservoirs are discussed and compared with regard to bacterial cell counts and particle characteristics, which were dependent, to a certain extent, on different flow rates and turbulence of the water environments.

  20. Occurrence and Control of Legionella in Recycled Water Systems

    Science.gov (United States)

    Jjemba, Patrick K.; Johnson, William; Bukhari, Zia; LeChevallier, Mark W.

    2015-01-01

    Legionella pneumophila is on the United States Environmental Protection Agency (USEPA) Candidate Contaminant list (CCL) as an important pathogen. It is commonly encountered in recycled water and is typically associated with amoeba, notably Naegleria fowleri (also on the CCL) and Acanthamoeba sp. No legionellosis outbreak has been linked to recycled water and it is important for the industry to proactively keep things that way. A review was conducted examine the occurrence of Legionella and its protozoa symbionts in recycled water with the aim of developing a risk management strategy. The review considered the intricate ecological relationships between Legionella and protozoa, methods for detecting both symbionts, and the efficacy of various disinfectants. PMID:26140674

  1. Hydrologic control on water trade in dry land areas

    Science.gov (United States)

    Pande, S.

    2009-12-01

    Water resource (and agriculture) in arid/semi arid areas, especially in developing countries, is increasingly under pressure in the face of global change. While expansion of physical infrastructure such as expansion of irrigation or dam structures can help, many (such as International Monetary Fund) have emphasized introduction of other adaptive mechanisms, such as the use of financial instruments, to smooth out fluctuations in water availability (or agricultural income) caused by (even increasing) erraticity in rainfall patterns. One such mechanism is water trade, where a downstream agent makes a payment to an upstream agent for additional natural flow and if the upstream agent agrees she releases additional flow by changing her landuse pattern. However, such a mechanism is fraught with questions ranging from region to region physical and financial viability of trade in water, role of hydrology in its viability, to the challenges of implementing it in developing countries. Answers to such questions are of utmost importance if water trade is to be considered as a serious coping mechanism. This paper delves on the role that hydrology, specifically hydrologic properties, plays in viability of water trade in a region. We consider water management at basin level, each of the agents (here a ‘representative’ water use, for eg. a farmer) occupies a sub-catchment within a basin and hydrology underlying each such agent is represented by a lumped single linear reservoir model. This allows us to consider non-steady state conditions at monthly scale while calculating prices of water trade securities between contiguous agents based on partial equilibrium modeling. A novel result from this innovative approach is that equilibrium pricing of water trade depends on “effective” hydraulic conductivity of the basin as well as erraticity in rainfall. We implement and present the results for basins in Gujarat and Rajasthan, two semi-arid states in western India that are most

  2. Gated or ungated : water control in government-built irrigation systems : comparative research in Nepal

    NARCIS (Netherlands)

    Pradhan, T.M.S.

    1996-01-01


    The control, allocation and distribution, of water is the core process of an irrigation system. It is the process by which the available water is divided and distributed to the smaller irrigation units within the system, which in turn is distributed further down to the individual water us

  3. Gated or ungated water control in government-built irrigation systems. Comparative research in Nepal.

    NARCIS (Netherlands)

    Pradhan, T.M.S.

    1996-01-01

    The control, allocation and distribution, of water is the core process of an irrigation system. It is the process by which the available water is divided and distributed to the smaller irrigation units within the system, which in turn is distributed further down to the individual water user who must

  4. 45 CFR 2543.86 - Clean Air Act and the Federal Water Pollution Control Act.

    Science.gov (United States)

    2010-10-01

    ... 45 Public Welfare 4 2010-10-01 2010-10-01 false Clean Air Act and the Federal Water Pollution... Water Pollution Control Act. Contracts and subgrants of amounts in excess of $100,000 shall contain a... regulations issued pursuant to the Clean Air Act (42 U.S.C. 7401 et seq.) and the Federal Water...

  5. Gated or ungated : water control in government-built irrigation systems : comparative research in Nepal

    NARCIS (Netherlands)

    Pradhan, T.M.S.

    1996-01-01


    The control, allocation and distribution, of water is the core process of an irrigation system. It is the process by which the available water is divided and distributed to the smaller irrigation units within the system, which in turn is distributed further down to the individual water

  6. Seawater ultrafiltration fouling control: Backwashing with demineralized water/SWRO permeate

    KAUST Repository

    Li, Sheng

    2012-09-01

    In this study, the effect of demineralized water backwashing on fouling control of seawater ultrafiltration was investigated. Seawater from Scheveningen beach in The Hague and a desalination plant of Evides Company at Zeeland in the Netherlands was used as feed water, while demineralized water and UF permeate were used as backwash water for a fouling control efficiency comparison under different fluxes and backwash durations. Furthermore, demineralized waters with 5 or 50 mmol/l NaCl were applied for backwashing as well, to check the influence of monovalent cations on UF fouling control. Additionally, SWRO permeate was used for backwashes in long-term experiments to check the possibility of it replacing demineralized water. Results show that seawater UF fouling control is substantially improved by demineralized water backwashing. However, due to the high salinity of seawater, more water was required to dilute the cation concentration and limit the dispersion effect near the membrane surface than was needed for surface water. A 2-min demineralized water backwash showed better fouling control efficiency than a 1-min backwash. Furthermore, the presence of monovalent cations in the backwash water deteriorated the fouling control efficiency of the backwash, indicating the existence of a charge screening effect. The demineralized water with 5 and 50 mmol/l NaCl both showed a similar fouling control efficiency which is better than the UF permeate backwash. The calcium ions in UF permeate probably deteriorates the fouling control efficiency by maintaining a Ca-bridging effect between the membranes and NOM. SWRO permeate backwashing successfully controls membrane fouling as well. © 2012 Elsevier B.V. All rights reserved.

  7. Learn About the Water Pollution Control (Section 106) Grant Program

    Science.gov (United States)

    Under CWA Section 106, EPA is authorized to provide grants to states, eligible interstate agencies, and eligible tribes to establish and administer programs, including enforcement programs,for the prevention, reduction, and elimination of water pollution.

  8. Corrosion and Corrosion Control in Light Water Reactors

    Science.gov (United States)

    Gordon, Barry M.

    2013-08-01

    Serious corrosion problems have plagued the light water reactor (LWR) industry for decades. The complex corrosion mechanisms involved and the development of practical engineering solutions for their mitigation will be discussed in this article. After a brief overview of the basic designs of the boiling water reactor (BWR) and pressurized water reactor (PWR), emphasis will be placed on the general corrosion of LWR containments, flow-accelerated corrosion of carbon steel components, intergranular stress corrosion cracking (IGSCC) in BWRs, primary water stress corrosion cracking (PWSCC) in PWRs, and irradiation-assisted stress corrosion cracking (IASCC) in both systems. Finally, the corrosion future of both plants will be discussed as plants extend their period of operation for an additional 20 to 40 years.

  9. ENVIRONMENTAL POLLUTION CONTROL ALTERNATIVES: DRINKING WATER TREATMENT FOR SMALL COMMUNITIES

    Science.gov (United States)

    This document provides information for small system owners, operators, managers, and local decision makers, such as town officials, regarding drinking water treatment requirements and the treatment technologies suitable for small systems. t is not intended to be a comprehensive m...

  10. Water quality control program in experimental circuits; Programa de controle de qualidade da agua em circuitos experimentais

    Energy Technology Data Exchange (ETDEWEB)

    Cegalla, Miriam A. [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo, SP (Brazil)

    1996-07-01

    The Water Quality Control Program of the Experimental Circuits visualizes studying the water chemistry of the cooling in the primary and secondary circuits, monitoring the corrosion of the systems and studying the mechanism of the corrosion products transport in the systems. (author)

  11. Gated or ungated : water control in government-built irrigation systems : comparative research in Nepal

    OpenAIRE

    Pradhan, T.M.S.

    1996-01-01


    The control, allocation and distribution, of water is the core process of an irrigation system. It is the process by which the available water is divided and distributed to the smaller irrigation units within the system, which in turn is distributed further down to the individual water user who must control it to place it in the crop root zones in particular fields. This study is based on the thesis that water control is a function of both technical/engineering, and organizational ...

  12. Reducing energy consumption and leakage by active pressure control in a water supply system

    NARCIS (Netherlands)

    Bakker, M.; Rajewicz, T.; Kien, H.; Vreeburg, J.H.G.; Rietveld, L.C.

    2013-01-01

    WTP Gruszczyn supplies drinking water to a part of the city of Poznań, in the Midwest of Poland. For the optimal automatic pressure control of the clear water pumping station, nine pressure measuring points were installed in the distribution network, and an active pressure control model was

  13. Reducing energy consumption and leakage by active pressure control in a water supply system

    NARCIS (Netherlands)

    Bakker, M.; Rajewicz, T.; Kien, H.; Vreeburg, J.H.G.; Rietveld, L.C.

    2013-01-01

    WTP Gruszczyn supplies drinking water to a part of the city of Poznań, in the Midwest of Poland. For the optimal automatic pressure control of the clear water pumping station, nine pressure measuring points were installed in the distribution network, and an active pressure control model was develope

  14. Water Pollution Control Training: The Educational Role of the United States Environmental Protection Agency.

    Science.gov (United States)

    Williams, Frederick D.

    Presented are the results of a study to determine the perceived needs of environmental control education programs as seen by students, instructors, deans or program directors, and field-related employers in the field of water pollution control. Data were collected utilizing three approaches: survey instruments, information from Water Quality…

  15. Water Pollution Control Training: The Educational Role of the United States Environmental Protection Agency.

    Science.gov (United States)

    Williams, Frederick D.

    Presented are the results of a study to determine the perceived needs of environmental control education programs as seen by students, instructors, deans or program directors, and field-related employers in the field of water pollution control. Data were collected utilizing three approaches: survey instruments, information from Water Quality…

  16. Occurrence and Control of Legionella in Recycled Water Systems

    Directory of Open Access Journals (Sweden)

    Patrick K. Jjemba

    2015-07-01

    Full Text Available Legionella pneumophila is on the United States Environmental Protection Agency (USEPA Candidate Contaminant list (CCL as an important pathogen. It is commonly encountered in recycled water and is typically associated with amoeba, notably Naegleria fowleri (also on the CCL and Acanthamoeba sp. No legionellosis outbreak has been linked to recycled water and it is important for the industry to proactively keep things that way. A review was conducted examine the occurrence of Legionella and its protozoa symbionts in recycled water with the aim of developing a risk management strategy. The review considered the intricate ecological relationships between Legionella and protozoa, methods for detecting both symbionts, and the efficacy of various disinfectants.

  17. Olive oil waste waters: Controlled fermentation and materials recovery

    Energy Technology Data Exchange (ETDEWEB)

    Federici, F.; Montedoro, G.F.; Pozzi, V. (Tuscia Univ., Viterbo (Italy). Detp. di Agrobiologia e Agrochimica Perugia Univ. (Italy). Ist. di Industrie Agrarie UNIECO s.c.r.l., Reggio Emilia (Italy))

    Land and water pollution due to waste water and oils deriving from the processing of olives to produce oil represents a serious environmental problem for Spain, Italy and Greece. This paper reports and discusses the results (time dependent enzyme activity) of performance tests on an innovative fermentation process to be used in olive oil waste water anaerobic digestion. An outline is then given of a demonstration depolymerization/materials recovery (including polyphenols, enzymes, etc.) process scheme based on the the tested fermentation method. The fermentation process tests involved the use of an albidus yeast in an Applikon bench scale experimental device. Process parameters were varied to determine optimum fermentation conditions. The European Communities sponsored one cubic meter/day demonstration plant utilizes a preliminary treatment process based on the use of gelatin, bentonite and polyclar.

  18. Offset-Free Model Predictive Control of Open Water Channel Based on Moving Horizon Estimation

    Science.gov (United States)

    Ekin Aydin, Boran; Rutten, Martine

    2016-04-01

    Model predictive control (MPC) is a powerful control option which is increasingly used by operational water managers for managing water systems. The explicit consideration of constraints and multi-objective management are important features of MPC. However, due to the water loss in open water systems by seepage, leakage and evaporation a mismatch between the model and the real system will be created. These mismatch affects the performance of MPC and creates an offset from the reference set point of the water level. We present model predictive control based on moving horizon estimation (MHE-MPC) to achieve offset free control of water level for open water canals. MHE-MPC uses the past predictions of the model and the past measurements of the system to estimate unknown disturbances and the offset in the controlled water level is systematically removed. We numerically tested MHE-MPC on an accurate hydro-dynamic model of the laboratory canal UPC-PAC located in Barcelona. In addition, we also used well known disturbance modeling offset free control scheme for the same test case. Simulation experiments on a single canal reach show that MHE-MPC outperforms disturbance modeling offset free control scheme.

  19. Does mountain permafrost in Mongolia control water availability?

    Science.gov (United States)

    Menzel, Lucas; Kopp, Benjamin; Munkhjargal, Munkhdavaa

    2016-04-01

    In semi-arid Mongolia, continuous and discontinuous permafrost covers wide parts of the mountains, especially in the northwest of the country. Long-term analysis of annual discharge from rivers draining the mountainous parts shows high temporal variability, with some evidence of decreasing trends, accompanied by decreased intra-annual variability. Investigations show that annual precipitation features small changes while annual air temperature significantly increased over the last decades, with warming rates clearly outranging the global average. Widespread and drastic changes in land cover through forest fires in northern Mongolia might have an additional impact on water retention and the stability of permafrost. Hence, there is concern about an increased degradation of mountain permafrost and a possible impact on river discharge and water availability. Decreased water availability from the mountains would have strong socio-economic implications for the population living in the steppe belt downstream the mountains. Therefore, a monitoring program has been conducted in northern Mongolia that aims to improve the understanding of how climate change and forest fires are influencing mountain permafrost and water resources. The study region, Sugnugur valley, is located about 100 km north of Ulaanbaatar and includes the transition belt between the steppe, the boreal zone and the alpine tundra of the Khentii Mountains. Extensive measurements of soil temperatures, soil moisture, discharge and climatic parameters have been carried out along transects which stretch across the Sugnugur river valley and include steppe, boreal forest as well as burnt forest. First results indicate that the environmental conditions show drastic changes after forest fire, with reduced water retention in the headwaters. After forest fires, changing runoff processes above the permafrost table have been observed, where water drains rapidly along preferential flow paths. This eventually leads to

  20. Application of Cooling Water in Controlled Runout Table Cooling on Hot Strip Mill

    Institute of Scientific and Technical Information of China (English)

    LIU Zheng-dong; I V Samarasekera

    2004-01-01

    The controlled runout table cooling is essential in determining the final mechanical properties and flatness of steel strip. The heat of a hot steel strip is mainly extracted by cooling water during runout. In order to study the heat transfer by water jet impingement boiling during runout, a pilot facility was constructed at the University of British Columbia. On this pilot facility, the water jet impingement tests were carried out under various cooling conditions to investigate the effect of processing parameters, such as cooling water temperature, water jet impingement velocity, initial strip temperature, water flow rate, water nozzle diameter and array of water nozzles, on the heat transfer of heated strip. The results obtained contribute to the optimization of cooling water during runout.

  1. Worldwide Eutrophication of Water Bodies: Causes, Concerns, Controls

    Science.gov (United States)

    Prepas, E. E.; Charette, T.

    2003-12-01

    Eutrophication is the nutrient enrichment of waters that stimulates an array of symptomatic changes, that can include increased phytoplankton and rooted aquatic plant (macrophyte) production, fisheries and water quality deterioration, and other undesirable changes that interfere with water uses (Bartsch, 1972). The trophic state, or degree of fertility, of water bodies ranges from oligotrophic to mesotrophic to eutrophic with increasing supply of nutrients and organic matter ( Table 1). Eutrophication is most often the result of an elevated supply of nutrients, particularly nitrogen and phosphorus, to surface waters that results in enhanced production of primary producers, particularly phytoplankton and aquatic plants. Table 1. Mean annual values for the trophic classification system Total phosphorus (μg L-1)Chlorophyll a (μg L-1)Secchi disk depth (m) Ultra-oligotrophic12 Oligotrophic6 Mesotrophic10-352.5-86-3 Eutrophic35-1008-253-1.5 Hypertrophic>100>25systems can lead to high decomposition rates by bacteria. Dissolved oxygen consumption by decomposers, combined with a barrier to gas exchange (thermocline or ice cover), can reduce (hypoxia) or eliminate (anoxia) dissolved oxygen in bottom waters. (A thermocline is the junction between an upper layer of warm, less dense water (the epilimnion) and a deeper layer of cold water (the hypolimnion). When this stratification is in place, the typically oxygen-rich waters of the epilimnion do not mix with the waters of the hypolimnion.) Oxygen depletion is one of the most harmful side effects of eutrophication because it can cause catastrophic fish kills, devastating local fisheries.The accumulation of plant biomass depends on the addition of factors that stimulate plant growth. On average, the macronutrients nitrogen and phosphorus are present in marine phytoplankton at an atomic ratio 16 : 1 (Redfield, 1958). The ratio of nitrogen to phosphorus in freshwaters tends to be greater than the ratio in phytoplankton

  2. Unit process engineering for water quality control and biosecurity in marine water recirculating systems

    Science.gov (United States)

    High-intensity systems that treat and recirculate water must maintain a culture environment that can sustain near optimum fish health and growth at the design carrying capacity. Water recirculating systems that use centralized treatment systems can benefit from the economies of scale to decrease th...

  3. Numerical Study of Water Control with Downhole Oil-Water Separation Technology

    Directory of Open Access Journals (Sweden)

    Yin Khor Yin

    2014-07-01

    Full Text Available The maturing oil fields with increasing water production can pose a challenging produced water handling and disposal issues. This paper presents a numerical study of a motorless hydrocyclone to enhance understanding of the downhole oil-water separation. The turbulence of fluid flow is obtained using K-ε Realizable Turbulence model for complex swirl dominated flow, while the interface between hydrocarbon and water is described using the Discrete Phase model. In this approach, factors which contribute to the hydrocyclone separation instability were discussed. Discussion is then extended to the relationship of residence time with pressure difference between overflow and underflow. These pressure differences are able to relate to pressure condition for high water cut well which require downhole separation.

  4. A controlled experiment for water front monitoring using GPR technology

    NARCIS (Netherlands)

    Miorali, M.; Slob, E.C.; Arts, R.J.

    2010-01-01

    We use a stepped frequency continuous wave (SFCW) radar and an impulse radar to monitor a water flood experiment in a sand box. The SFCW system operates in the bandwidth from 800 MHz to 2.8 GHz. The impulse radar system is bi-static and works with a central frequency of 1 GHz. The sand box is a mete

  5. design and implementation of a water level controller

    African Journals Online (AJOL)

    2012-03-01

    Mar 1, 2012 ... ... E.C. Anoliefod,a a. National Ctr. For Energy Research and Development, Univ. of Nigeria Nsukka ... Experimental performance results indicated that the device is quite suitable for .... the water level indicator. In the design ...

  6. CONTROLLING STORM WATER RUNOFF WITH TRADABLE CREDITS FOR IMPERVIOUS SURFACES

    Science.gov (United States)

    Storm water flow off impervious surface in a watershed can lead to stream degradation, habitat alteration, low base flows and toxic leading. We show that a properly designed tradable runoff credit (TRC) system creates economic incentives for landowners to employ best management p...

  7. an automatic safety control for immersion water heater

    African Journals Online (AJOL)

    NIJOTECH

    heater in the Nigerian market in its current form is depicted ... the comparator used is an open collector type. It is instructive to take a close look at the operation of the Schmitt trigger. The equivalent .... additional advantage of keeping the water.

  8. A controlled experiment for water front monitoring using GPR technology

    NARCIS (Netherlands)

    Miorali, M.; Slob, E.C.; Arts, R.J.

    2010-01-01

    We use a stepped frequency continuous wave (SFCW) radar and an impulse radar to monitor a water flood experiment in a sand box. The SFCW system operates in the bandwidth from 800 MHz to 2.8 GHz. The impulse radar system is bi-static and works with a central frequency of 1 GHz. The sand box is a

  9. Acoustic control of mosquito larvae in artificial drinking water containers

    Science.gov (United States)

    Acoustic larvicide devices are part of an emerging technology that provides a non-chemical and non-biological means to reduce larval populations of key medically important mosquito species such as Aedes aegypti in containers or catchments of water. These devices could benefit integrated vector manag...

  10. Model-Based Control of Drinking-Water Treatment Plants

    NARCIS (Netherlands)

    Van Schagen, K.M.

    2009-01-01

    The drinking water in the Netherlands is of high quality and the production cost is low. This is the result of extensive research in the past decades to innovate and optimise the treatment processes. The processes are monitored and operated by motivated and skilled operators and process technologist

  11. Real-time monitoring and operational control of drinking-water systems

    CERN Document Server

    Ocampo-Martínez, Carlos; Pérez, Ramon; Cembrano, Gabriela; Quevedo, Joseba; Escobet, Teresa

    2017-01-01

    This book presents a set of approaches for the real-time monitoring and control of drinking-water networks based on advanced information and communication technologies. It shows the reader how to achieve significant improvements in efficiency in terms of water use, energy consumption, water loss minimization, and water quality guarantees. The methods and approaches presented are illustrated and have been applied using real-life pilot demonstrations based on the drinking-water network in Barcelona, Spain. The proposed approaches and tools cover: • decision-making support for real-time optimal control of water transport networks, explaining how stochastic model predictive control algorithms that take explicit account of uncertainties associated with energy prices and real demand allow the main flow and pressure actuators—pumping stations and pressure regulation valves—and intermediate storage tanks to be operated to meet demand using the most sustainable types of source and with minimum electricity costs;...

  12. Control-oriented modeling and real-time control for the ozone dosing process of drinking water treatment.

    Science.gov (United States)

    Wang, Dongsheng; Li, Shihua; Zhou, Xingpeng

    2013-03-01

    Ozonation is one of the most important steps during drinking water treatment. To improve the efficiency of ozonation and to stabilize the quality of the treated water, control-oriented modeling and a real-time control method for the ozone dosing process are developed in this study. Compared with existing ozonation models developed by bench-scale and pilot-scale batch experiments, the model reported herein is control-oriented and based on plant-scale batch experiments. A real-time control strategy for maintaining a constant ozone exposure is attempted to meet primary disinfection requirements. An internal model control scheme is proposed to maintain a constant ozone exposure by adjusting the ozone dosage. The proposed real-time control method can cope with changing water quality, water flow rate, and process operational conditions. Both simulations and experimental studies have been carried out and implemented for the ozone dosing process control system, and the results demonstrate the effectiveness and practicality of this real-time control method.

  13. Feedback control of water supply in an NFT growing system

    NARCIS (Netherlands)

    Gieling, Th.H.; Janssen, H.J.J.; Vries, de H.C.; Loef, P.

    2001-01-01

    The paper explores a concept of irrigation control, where the supply of nutrient solution is controlled without the use of predictive uptake models but rather by the use of a direct feedback of a drain flow measurement. This concept proves to be a viable approach. Results are presented, showing the

  14. Differential responses of plumbagin content in Plumbago zeylanica L. (Chitrak under controlled water stress treatments

    Directory of Open Access Journals (Sweden)

    Kharadi R.

    2011-12-01

    Full Text Available A pot experiment was conducted on Plumbago zeylanica L. (Chitrak under controlled water stress environment in greenhouse during the kharif season. The experiment was laid out in completely randomized design with five treatments of different water stress levels i.e. control, 20%, 40%, 60% and 80% and four replications. Out of five stress levels, 80% water stress has influenced root length, dry herbage, plumbagin, potassium and proline content. In control conditions the plant height, number of leaf, total leaf area, stomatal conductance, transpiration rate, photosynthesis, CO2 utilization, H2O utilization and chlorophyll were found to be maximum. The impact of water stress on plumbagin content has shown increase trend with respect to different water stress levels that is maximum at 80 % and minimum at control.

  15. Control of water erosion and sediment in open cut coal mines in tropical areas

    Energy Technology Data Exchange (ETDEWEB)

    Ueda, T.; Nugraha, C.; Matsui, K.; Shimada, H.; Ichinose, M.; Gottfried, J. [Kyushu University, Fukuoka (Japan). Department of Earth Resources Engineering

    2005-07-01

    The purpose is to reduce the environmental impacts from open cut mining in tropical areas, such as Indonesia and Vietnam. Research conducted on methods for the control of water erosion and sediment from open cut coal mines is described. Data were collected on climate and weathering in tropical areas, mechanism of water erosion and sedimentation, characteristics of rocks in coal measures under wet conditions, water management at pits and haul roads and ramps, and construction of waste dumps and water management. The results will be applied to the optimum control and management of erosion and sediments in open cut mining. 6 refs., 8 figs.

  16. Design study of water chemistry control system for IASCC irradiation test

    Energy Technology Data Exchange (ETDEWEB)

    Mori, Yuichiro; Ide, Hiroshi; Nabeya, Hideaki [Japan Atomic Energy Research Inst., Oarai, Ibaraki (Japan). Oarai Research Establishment; Tsukada, Takashi [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    2002-02-01

    In relation to the aging of Light Water Reactor (LWR), the Irradiation Assisted Stress Corrosion Cracking (IASCC) has been regarded as a significant and urgent issue for the reliability of in-core components of LWR, and the irradiation research on the IASCC is now under schedule. With the progress of the irradiation research on reactor materials, well-controlled environment conditions during irradiation testing are required. Especially for irradiation testing of IASCC studies, water chemistry control is essential in addition to the control of neutron fluence and irradiation temperature. According to these requirements, at the Japan Atomic Energy Research Institute (JAERI), an irradiation testing facility that simulates in-core environment of Boiling Water Reactor (BWR) has been designed to be installed in the Japan Materials Testing Reactor (JMTR). This facility is composed of the Saturated Temperature Capsules (SATCAP) that are installed into the JMTR's core to irradiate material specimens, the Water Control Unit that is able to supply high-temperature and high-pressure chemical controlled water to SATCAP, and other components. This report describes the design study of water chemistry control system of the Water Control Unit. The design work has been performed in the fiscal year 1999. (author)

  17. Main Injector Lcw (low Conductivity Water) Control System

    CERN Document Server

    Seino, K C

    2001-01-01

    There are six service buildings uniformly spaced along the perimeter of MI (Main Injector). A total of 18 LCW pumps were installed around the MI ring with 3 pumps per building. Approximately 8,000 GPM of LCW is required to cool magnets, bus and power supplies in the MI enclosure and service buildings. In each service building, a PLC control system controls pumps and valves, and it monitors pressures, flow, resistivities and temperatures. The PLC hardware system consists of a Gateway module and a variety of I/O modules, which are made by Sixnet of Clifton Park, NY. The control system communicates with other buildings including MCR (Main Control Room) via an Ethernet link and front-end computers. For more details of the MI LCW control system, refer to [1] and [2]. One of the key elements of the PLC software is called ISaGRAF workbench, which was created by CJ International of Seyssins, France. The workbench provides a comprehensive control-programming environment, where control programs can be written in five d...

  18. Water-friendly virtual reality pain control during wound care.

    Science.gov (United States)

    Hoffman, Hunter G; Patterson, David R; Magula, Jeff; Carrougher, Gretchen J; Zeltzer, Karen; Dagadakis, Stephen; Sharar, Sam R

    2004-02-01

    Recent research suggests that entering an immersive virtual environment can serve as a powerful nonpharmacologic analgesic for severe burn pain. The present case study describes an attempt to use water-friendly virtual reality (VR) technology with a burn patient undergoing wound care in a hydrotherapy tub. The patient was a 40-year-old male with 19% total body surface area deep flame/flash burns to his legs, neck, back, and buttocks. The virtual reality treatment decreased the patient's sensory and affective pain ratings and decreased the amount of time spent thinking about his pain during wound care. We believe that VR analgesia works by drawing attention away from the wound care, leaving less attention available to process incoming pain signals. The water-friendly VR helmet dramatically increases the number of patients with severe burns that could potentially be treated with VR (see http://www.vrpain.com).

  19. The water question in feminism: water control and gender inequities in a neo-liberal era

    NARCIS (Netherlands)

    Ahlers, R.; Zwarteveen, M.Z.

    2009-01-01

    The current neo-liberal moment in water policy appears to offer possibilities for realizing feminist ambitions. Several feminist scholars see the individualization and privatization of resource rights as offering possibilities for confronting gender inequalities rooted in, and reproduced by,

  20. Surfactant controlled switching of water-in-oil wetting behaviour of porous silica films grown at oil-water interfaces

    Indian Academy of Sciences (India)

    Manish M Kulkarni; Rajdip Bandyopadhyaya; Ashutosh Sharma

    2008-11-01

    Selective permeation of oil and water across a porous medium, as in oil recovery operations, depends on the preferential wetting properties of the porous medium. We show a profound influence of surfactants in wetting of porous media and thus demonstrate a new route for the control of water-in-oil wetting of porous substrates by changing the concentration of surfactants in an aqueous sub-phase below the substrate. This strategy is employed to engineer partial reversible wetting transitions on a porous silica film. The film itself is grown and stabilized on a flat, macroscopic interface between an oil phase and an aqueous sub-phase. On increasing the surfactant (CTAB) concentration in the sub-phase, contact angle of a water drop (placed on the oil side of the film) changes from 140° to 16° in 25 min by diffusion of the surfactant across the porous film. On further replacement of the sub-phase with pure water, diffusion of the surfactant from the water drop back to the sub-phase was slower, increasing the contact angle in the process from 16° to 90° in 2 h. Wettability control by a cationic surfactant (CTAB) was found to be much faster (6 deg/min) than that offered by an anionic surfactant, SDS (0.05 deg/min). Switching of the surface wettability due to the surfactant diffusion may have implications in oil-water separation, chemical bed reactors and microfluidic devices.

  1. Design and Implementation of a Water Level Controller using Fuzzy Logic

    Directory of Open Access Journals (Sweden)

    Namrata Dey

    2013-06-01

    Full Text Available This paper analyzes the effectiveness of water level control using fuzzy logic. The water level in the tank is sensed using transistor switching principle. The level sensed is fed to the PIC16 microcontroller. The user provides the set point to the microcontroller through serial communication using the COM development port software, Terminal. It computes the error as the difference between the set point and the process variable. The fuzzy logic programmed in the microcontroller is applied which controls the water level in the tank using the drain and the feed pumps. Once the set point has been reached, the message along with the present level is sent back through serial communication to the user interface on a PC. Thus, the water level in the tank is controlled according to the set point given by the user. The implementation of a fuzzy level controller has many applications such as boiler drum level control, reverse osmosis plant, demineralisation plant etc.

  2. microcontroller based automatic control for water pumping machine ...

    African Journals Online (AJOL)

    user

    efforts to store and retrieve it when needed by the development of ... the challenges of achieving high energy efficiency and extended ... complexity, hence reduced high cost and energy .... Frequency Control", Jordan Journal of Mechanical.

  3. Organic carbon decomposition rates controlled by water retention time across inland waters

    Science.gov (United States)

    Catalán, Núria; Marcé, Rafael; Kothawala, Dolly N.; Tranvik, Lars. J.

    2016-07-01

    The loss of organic carbon during passage through the continuum of inland waters from soils to the sea is a critical component of the global carbon cycle. Yet, the amount of organic carbon mineralized and released to the atmosphere during its transport remains an open question, hampered by the absence of a common predictor of organic carbon decay rates. Here we analyse a compilation of existing field and laboratory measurements of organic carbon decay rates and water residence times across a wide range of aquatic ecosystems and climates. We find a negative relationship between the rate of organic carbon decay and water retention time across systems, entailing a decrease in organic carbon reactivity along the continuum of inland waters. We find that the half-life of organic carbon is short in inland waters (2.5 +/- 4.7 yr) compared to terrestrial soils and marine ecosystems, highlighting that freshwaters are hotspots of organic carbon degradation. Finally, we evaluate the response of organic carbon decay rates to projected changes in runoff. We calculate that regions projected to become drier or wetter as the global climate warms will experience changes in organic carbon decay rates of up to about 10%, which illustrates the influence of hydrological variability on the inland waters carbon cycle.

  4. Mechanism of Germacradien-4-ol Synthase-Controlled Water Capture

    Science.gov (United States)

    2016-01-01

    The sesquiterpene synthase germacradiene-4-ol synthase (GdolS) from Streptomyces citricolor is one of only a few known high-fidelity terpene synthases that convert farnesyl diphosphate (FDP) into a single hydroxylated product. Crystals of unliganded GdolS-E248A diffracted to 1.50 Å and revealed a typical class 1 sesquiterpene synthase fold with the active site in an open conformation. The metal binding motifs were identified as D80DQFD and N218DVRSFAQE. Some bound water molecules were evident in the X-ray crystal structure, but none were obviously positioned to quench a putative final carbocation intermediate. Incubations in H218O generated labeled product, confirming that the alcohol functionality arises from nucleophilic capture of the final carbocation by water originating from solution. Site-directed mutagenesis of amino acid residues from both within the metal binding motifs and without identified by sequence alignment with aristolochene synthase from Aspergillus terreus generated mostly functional germacradien-4-ol synthases. Only GdolS-N218Q generated radically different products (∼50% germacrene A), but no direct evidence of the mechanism of incorporation of water into the active site was obtained. Fluorinated FDP analogues 2F-FDP and 15,15,15-F3-FDP were potent noncompetitive inhibitors of GdolS. 12,13-DiF-FDP generated 12,13-(E)-β-farnesene upon being incubated with GdolS, suggesting stepwise formation of the germacryl cation during the catalytic cycle. Incubation of GdolS with [1-2H2]FDP and (R)-[1-2H]FDP demonstrated that following germacryl cation formation a [1,3]-hydride shift generates the final carbocation prior to nucleophilic capture. The stereochemistry of this shift is not defined, and the deuteron in the final product was scrambled. Because no clear candidate residue for binding of a nucleophilic water molecule in the active site and no significant perturbation of product distribution from the replacement of active site residues were

  5. Quality-control results for ground-water and surface-water data, Sacramento River Basin, California, National Water-Quality Assessment, 1996-1998

    Science.gov (United States)

    Munday, Cathy; Domagalski, Joseph L.

    2003-01-01

    Evaluating the extent that bias and variability affect the interpretation of ground- and surface-water data is necessary to meet the objectives of the National Water-Quality Assessment (NAWQA) Program. Quality-control samples used to evaluate the bias and variability include annual equipment blanks, field blanks, field matrix spikes, surrogates, and replicates. This report contains quality-control results for the constituents critical to the ground- and surface-water components of the Sacramento River Basin study unit of the NAWQA Program. A critical constituent is one that was detected frequently (more than 50 percent of the time in blank samples), was detected at amounts exceeding water-quality standards or goals, or was important for the interpretation of water-quality data. Quality-control samples were collected along with ground- and surface-water samples during the high intensity phase (cycle 1) of the Sacramento River Basin NAWQA beginning early in 1996 and ending in 1998. Ground-water field blanks indicated contamination of varying levels of significance when compared with concentrations detected in environmental ground-water samples for ammonia, dissolved organic carbon, aluminum, and copper. Concentrations of aluminum in surface-water field blanks were significant when compared with environmental samples. Field blank samples collected for pesticide and volatile organic compound analyses revealed no contamination in either ground- or surface-water samples that would effect the interpretation of environmental data, with the possible exception of the volatile organic compound trichloromethane (chloroform) in ground water. Replicate samples for ground water and surface water indicate that variability resulting from sample collection, processing, and analysis was generally low. Some of the larger maximum relative percentage differences calculated for replicate samples occurred between samples having lowest absolute concentration differences and(or) values near

  6. A theoretical study of the modelling and control of a solar water electrolysis plant

    Science.gov (United States)

    Vandergeest, P.; Fahidy, T. Z.

    1980-01-01

    A control-oriented model is presented for a hydrogen producing plant consisting of a conventional water electrolysis process and a photo-assisted water electrolytic installation which utilizes solar energy via a suitable semiconductor/electrolyte assembly. A control strategy for daily hydrogen production is illustrated by a numerical example. The proposed simulation of solar water electrolysis plants is of potential usefulness for automatic control of the photoelectrolytic process when combined with statistical data-logging and model updating carried out in a practical installation.

  7. Local drinking water filters reduce diarrheal disease in Cambodia: a randomized, controlled trial of the ceramic water purifier.

    Science.gov (United States)

    Brown, Joe; Sobsey, Mark D; Loomis, Dana

    2008-09-01

    A randomized, controlled intervention trial of two household-scale drinking water filters was conducted in a rural village in Cambodia. After collecting four weeks of baseline data on household water quality, diarrheal disease, and other data related to water use and handling practices, households were randomly assigned to one of three groups of 60 households: those receiving a ceramic water purifier (CWP), those receiving a second filter employing an iron-rich ceramic (CWP-Fe), and a control group receiving no intervention. Households were followed for 18 weeks post-baseline with biweekly follow-up. Households using either filter reported significantly less diarrheal disease during the study compared with a control group of households without filters as indicated by longitudinal prevalence ratios CWP: 0.51 (95% confidence interval [CI]: 0.41-0.63); CWP-Fe: 0.58 (95% CI: 0.47-0.71), an effect that was observed in all age groups and both sexes after controlling for clustering within households and within individuals over time.

  8. WATER QUALITY MODELING AND POLLUTION CONTROL FOR THE EASTERN ROUTE OF SOUTH TO NORTH WATER TRANSFER PROJECT IN CHINA

    Institute of Scientific and Technical Information of China (English)

    WANG Chao; WANG Yan-ying; WANG Pei-fang

    2006-01-01

    South to North Water Transfer Project in China is the largest project over centuries to solve the water shortage problem in vast areas of northern China. It comprises of three routes: the eastern, central and western route and this study mainly focused on the eastern route. As water quality is the key factor for the eastern route, this paper examined the main factors influencing water quality of the main route south of the Yellow River, by investigating the point source, non-point source (diffusive source) and internal source pollutions along the main eastern route and in its drainage basins, and assessing the current water quality in the waterways. According to the complicated and combined systems of rivers and lakes in this route, one-dimensional water quantity and quality model for rivers and two-dimensional model for lakes were developed to simulate the hydrodynamic and pollutant transport processes. The numerical method and model algorithm were described. The values of model parameters were estimated by using field-monitoring data along the main route and the inverse modeling technique. Established models were employed to predict the degradations of CODMn and NH4+-N in the main stream, under the conditions of current pollution loads and different hydrologic conditions. Schemes were present for controlling total quantities of pollutants from point source and non-point source along the main route to secure water quality for the eastern route.

  9. Breaking the Chain of Infection: Dental Unit Water Quality Control

    Science.gov (United States)

    Pawar, Amrita; Mehta, Sonia; Dang, Rajat

    2016-01-01

    Introduction The air–water syringes, ultrasonic scalers, high speed air turbine handpieces are connected to dental units by a network of small-bore plastic tubes through which water and air travel to activate or cool the instruments and it had been shown that this system is extensively contaminated with microbial biofilms and pose a potential risk of infection for patients as well as dental professionals. Aim To evaluate and compare the efficacy of various disinfectants in reducing the microbial colony count in water derived from Dental Unit Waterlines. Materials and Methods Five random dental units were selected and samples were collected before and after intervention with 5 disinfectants (0.02% H2O2 continuously, 0.02% H2O2 continuously with shock treatment with 0.25% H2O2 weekly, 0.12% Chlorohexidine and 12% Ethanol overnight, 1:50 Original Listerine overnight, 2% Sodium Perborate and 2% EDTA 5 minutes in morning) using different disinfection methods for 4 weeks. Samples were cultured on Reasoner’s 2A (R2A) agar for microbial counting. Results Results were recorded as Colony forming units/ml (cfu/ml) and were evaluated statistically. Results showed that all the dental unit waterlines were heavily contaminated with microbes before any intervention. After 1 day of disinfection regime the counts reduced significantly and showed progressive reduction in consecutive weeks. Goals set by ADA & CDC were ultimately achieved at the end of 4 weeks. Conclusion All the disinfectants were equally effective in reducing the microbial colony count of DUWLs, irrespective of their concentration and method of disinfection. PMID:27630960

  10. Space Station Environmental Control and Life Support Systems: An Update on Waste Water Reclamation

    Science.gov (United States)

    Ferner, Kathleen M.

    1994-01-01

    Since the mid-1980's, work has been ongoing In the development of the various environmental control and life support systems (ECLSS) for the space station. Part of this effort has been focused on the development of a new subsystem to reclaim waste water that had not been previously required for shuttle missions. Because of the extended manned missions proposed, reclamation of waste water becomes imperative to avoid the weight penalties associated with resupplying a crew's entire water needs for consumption and daily hygiene. Hamilton Standard, under contract to Boeing Aerospace and Electronics, has been designing the water reclamation system for space station use. Since June of 1991, Hamilton Standard has developed a combined water processor capable of reclaiming potable quality water from waste hygiene water, used laundry water, processed urine, Shuttle fuel cell water, humidity condensate and other minor waste water sources. The system was assembled and then tested with over 27,700 pounds of 'real' waste water. During the 1700 hours of system operation required to process this waste water, potable quality water meeting NASA and Boeing specifications was produced. This paper gives a schematic overview of the system, describes the test conditions and test results and outlines the next steps for system development.

  11. PLIO: a generic tool for real-time operational predictive optimal control of water networks.

    Science.gov (United States)

    Cembrano, G; Quevedo, J; Puig, V; Pérez, R; Figueras, J; Verdejo, J M; Escaler, I; Ramón, G; Barnet, G; Rodríguez, P; Casas, M

    2011-01-01

    This paper presents a generic tool, named PLIO, that allows to implement the real-time operational control of water networks. Control strategies are generated using predictive optimal control techniques. This tool allows the flow management in a large water supply and distribution system including reservoirs, open-flow channels for water transport, water treatment plants, pressurized water pipe networks, tanks, flow/pressure control elements and a telemetry/telecontrol system. Predictive optimal control is used to generate flow control strategies from the sources to the consumer areas to meet future demands with appropriate pressure levels, optimizing operational goals such as network safety volumes and flow control stability. PLIO allows to build the network model graphically and then to automatically generate the model equations used by the predictive optimal controller. Additionally, PLIO can work off-line (in simulation) and on-line (in real-time mode). The case study of Santiago-Chile is presented to exemplify the control results obtained using PLIO off-line (in simulation).

  12. Development of a Robust Model-Based Water Level Controller for U-Tube Steam Generator

    Energy Technology Data Exchange (ETDEWEB)

    Basher, A.M.H.

    2001-09-04

    Poor control of steam generator water level of a nuclear power plant may lead to frequent nuclear reactor shutdowns. These shutdowns are more common at low power where the plant exhibits strong non-minimum phase characteristics and flow measurements at low power are unreliable in many instances. There is need to investigate this problem and systematically design a controller for water level regulation. This work is concerned with the study and the design of a suitable controller for a U-Tube Steam Generator (UTSG) of a Pressurized Water Reactor (PWR) which has time varying dynamics. The controller should be suitable for the water level control of UTSG without manual operation from start-up to full load transient condition. Some preliminary simulation results are presented that demonstrate the effectiveness of the proposed controller. The development of the complete control algorithm includes components such as robust output tracking, and adaptively estimating both the system parameters and state variables simultaneously. At the present time all these components are not completed due to time constraints. A robust tracking component of the controller for water level control is developed and its effectiveness on the parameter variations is demonstrated in this study. The results appear encouraging and they are only preliminary. Additional work is warranted to resolve other issues such as robust adaptive estimation.

  13. Safe household water treatment and storage using ceramic drip filters: a randomised controlled trial in Bolivia.

    Science.gov (United States)

    Clasen, T; Brown, J; Suntura, O; Collin, S

    2004-01-01

    A randomised controlled field trial was conducted to evaluate the effectiveness of ceramic drip filters to improve the microbiological quality of drinking water in a low-income community in rural Bolivia. In four rounds of water sampling over five months, 100% of the samples were free of thermotolerant (faecal) coliforms (TTC) compared to an arithmetic mean TTC count of 1517, 406, 167 and 245 among control households which continued to use their customary sources of drinking water. The filter systems produced water that consistently met WHO drinking-water standards despite levels of turbidity that presented a challenge to other low-cost POU treatment methods. The filter systems also demonstrated an ability to maintain the high quality of the treated water against subsequent re-contamination in the home.

  14. Adaptive Path Control of Surface Ships in Restricted Waters.

    Science.gov (United States)

    1980-08-01

    about the rudder model included in eq. (11), we assume exact knowledge of the rudder angle. Astrom and K9llstr6m18 note that all sensors have...properties of the ship o 11 and the control loop. Further, Astrom and Wittenmark have noted the fol- lowing conditions as necessary for the convergence...Symposium, VeL. 4, Annapolis, MD., Oct. 30-Nov. 3, 1978, pp. P 1-1 to P 1-13. 1-. Astrom , K.J., "Some Aspwcts, of the Control of Large Tankers

  15. Modeling and control of water disinfection process in annular photoreactors

    NARCIS (Netherlands)

    Keesman, K.J.; Vries, D.; Mourik, van S.; Zwart, H.J.; Tzafestas, S.

    2007-01-01

    As an alternative or addition to complex physical modeling, in this paper transfer function models of the disinfection process in annular photoreactors under different flow conditions are derived. These transfer function models allow an analytical evaluation of the system dynamics and the control st

  16. Chirality controlled responsive self-assembled nanotubes in water

    NARCIS (Netherlands)

    van Dijken, D. J.; Stacko, P.; Stuart, M. C. A.; Browne, W. R.; Feringa, B. L.

    2017-01-01

    The concept of using chirality to dictate dimensions and to store chiral information in self-assembled nanotubes in a fully controlled manner is presented. We report a photoresponsive amphiphile that co-assembles with its chiral counterpart to form nanotubes and demonstrate how chirality can be used

  17. Army Corps of Engineers: Additional Steps Needed for Review and Revision of Water Control Manuals

    Science.gov (United States)

    2016-07-01

    water supply, recreation, and fish and wildlife conservation. However, much of the Corps’ infrastructure for these dams and their associated...according to the report, a shift in precipitation from snow to rain , combined with earlier melting of mountain snowpack, has been documented in...statistical analysis of historical rain events. For those projects that have multiple authorized purposes, water control plans attempt to balance water

  18. Water Control System In The Great Dismal Swamp National Wildlife Refuge

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Reference is made to your letter of 21 September 1977, requesting a description of the water control system in the Great Dismal Swamp National Wildlife Refuge....

  19. System A and B Water Control Structure (WCS) Use in 2002

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This memo outlines the opening and closing of water control structures on St. Vincent National Wildlife Refuge in 2002. Wcs’s were opened for heavy rain in January...

  20. Formal Law and Local Water Control in the Andean Region: A Fiercely Contested Field

    NARCIS (Netherlands)

    Vos, de H.; Boelens, R.A.; Bustamente, R.R.

    2006-01-01

    Water access and control rights of peasant and indigenous communities in Andean countries are threatened. Vertical state law and intervention practices, as well as new privatization policies generally ignore, discriminate or undermine local normative frameworks. Recognition of diverse local rights

  1. Effects of Proposed Water Control Structure at Prime Hook National Wildlife Refuge 1981

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The United States Fish and Wildlife Service is studying the feasibility of constructing a water control structure on the Prime Hook National Wildlife Refuge. The...

  2. Environmental Assessment for the Reestablishment of Water Control Unit 2: Prime Hook National Wildlife Refuge: 1986

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — An environmental assessment for reestablishment of water control in Unit II of the Prime Hook National Wildlife Refuge was prepared in November, 1985. The Fish and...

  3. Small-signal modelling and control of photovoltaic based water pumping system.

    Science.gov (United States)

    Ghosh, Arun; Ganesh Malla, Siva; Narayan Bhende, Chandrasekhar

    2015-07-01

    This paper studies small-signal modelling and control design for a photovoltaic (PV) based water pumping system without energy storage. First, the small-signal model is obtained and then, using this model, two proportional-integral (PI) controllers, where one controller is used to control the dc-link voltage and the other one to control the speed of induction motor, are designed to meet control goals such as settling time and peak overshoot of the closed loop responses. The loop robustness of the design is also studied. For a given set of system parameters, simulations are carried out to validate the modelling and the control design.

  4. pH-controllable water permeation through a nanostructured copper mesh film.

    Science.gov (United States)

    Cheng, Zhongjun; Du, Ming; Fu, Kewei; Zhang, Naiqing; Sun, Kening

    2012-11-01

    Water permeation is an important issue in both fundamental research and industrial applications. In this work, we report a novel strategy to realize the controllable water permeation on the mixed thiol (containing both alkyl and carboxylic acid groups) modified nanostructured copper mesh films. For acidic and neutral water, the film is superhydrophobic, and the water cannot permeate the film because of the large negative capillary effect resulting from the nanostructures. For basic water, the film shows superhydrophilic property, and thus the water can permeate the film easily. The permeation process of water can be controlled just by simply altering the water pH. A detailed investigation indicates that nanostructures on the substrate and the appropriate size of the microscale mesh pores can enhance not only the static wettability but also the dynamic properties. The excellent controllability of water permeation is ascribed to the combined effect of the chemical variation of the carboxylic acid group and the microstructures on the substrate. This work may provide interesting insight into the new applications that are relevant to the surface wettability, such as filtration, microfluidic device, and some separation systems.

  5. The water question in feminism: water control and gender inequities in a neo-liberal era

    NARCIS (Netherlands)

    Ahlers, R.; Zwarteveen, M.Z.

    2009-01-01

    The current neo-liberal moment in water policy appears to offer possibilities for realizing feminist ambitions. Several feminist scholars see the individualization and privatization of resource rights as offering possibilities for confronting gender inequalities rooted in, and reproduced by, histori

  6. Parameter-less remote real-time control for the adjustment of pressure in water distribution systems

    CSIR Research Space (South Africa)

    Page, Philip R

    2017-09-01

    Full Text Available Reducing pressure in a water distribution system leads to a decrease in water leakage, decreased cracks in pipes, and consumption decreases. Pressure management includes an advanced type called remote real-time control. Here pressure control valves...

  7. Water

    Science.gov (United States)

    ... www.girlshealth.gov/ Home Nutrition Nutrition basics Water Water Did you know that water makes up more ... to drink more water Other drinks How much water do you need? top Water is very important, ...

  8. Risk of gastric cancer by water source: evidence from the Golestan case-control study.

    Directory of Open Access Journals (Sweden)

    Laura Eichelberger

    Full Text Available Gastric cancer (GC is the world's fifth most common cancer, and the third leading cause of cancer-related death. Over 70% of incident cases and deaths occur in developing countries. We explored whether disparities in access to improved drinking water sources were associated with GC risk in the Golestan Gastric Cancer Case Control Study.306 cases and 605 controls were matched on age, gender, and place of residence. We conducted unconditional logistic regression to calculate odds ratios (ORs and 95% confidence intervals (CI, adjusted for age, gender, ethnicity, marital status, education, head of household education, place of birth and residence, homeownership, home size, wealth score, vegetable consumption, and H. pylori seropositivity. Fully-adjusted ORs were 0.23 (95% CI: 0.05-1.04 for chlorinated well water, 4.58 (95% CI: 2.07-10.16 for unchlorinated well water, 4.26 (95% CI: 1.81-10.04 for surface water, 1.11 (95% CI: 0.61-2.03 for water from cisterns, and 1.79 (95% CI: 1.20-2.69 for all unpiped sources, compared to in-home piped water. Comparing unchlorinated water to chlorinated water, we found over a two-fold increased GC risk (OR 2.37, 95% CI: 1.56-3.61.Unpiped and unchlorinated drinking water sources, particularly wells and surface water, were significantly associated with the risk of GC.

  9. Scram simulation of a control rod drive mechanism of a pressurized water reactor under seismic conditions

    Energy Technology Data Exchange (ETDEWEB)

    Fujita, Katsuhisa; Shinohara, Yoshikazu; Ichinoo, Hiroyuki; Yoshikawa, Eiji; Nambu, Kiyoshi; Nomura, Tomonori.

    1987-03-01

    Control rod drop verification experiments of Mitsubishi pressurized water reactor under seismic conditions are performed to confirm the insertion function of control rods into the core. To evaluate these tests, computer simulations are performed. The scram time of control rods under seismic conditions was confirmed to meet the scram function. The behavior of the dropping control rods and the scram time obtained by the computer simulation show a very good correspondence with the results of verification experiments.

  10. Comparing a microbial biocide and chlorine as zebra mussel control strategies in an Irish drinking water treatment plant

    National Research Council Canada - National Science Library

    Sara Meehan; Frances E. Lucy; Bridget Gruber; Sarahann Rackl

    2013-01-01

    A need exists for an environmentally friendly mussel control method to replace chlorine and other traditional control methods currentlyutilised in drinking water plants and other infested facilities. Zequanox...

  11. Model Predictive Control-based Power take-off Control of an Oscillating Water Column Wave Energy Conversion System

    Science.gov (United States)

    Rajapakse, G.; Jayasinghe, S. G.; Fleming, A.; Shahnia, F.

    2017-07-01

    Australia’s extended coastline asserts abundance of wave and tidal power. The predictability of these energy sources and their proximity to cities and towns make them more desirable. Several tidal current turbine and ocean wave energy conversion projects have already been planned in the coastline of southern Australia. Some of these projects use air turbine technology with air driven turbines to harvest the energy from an oscillating water column. This study focuses on the power take-off control of a single stage unidirectional oscillating water column air turbine generator system, and proposes a model predictive control-based speed controller for the generator-turbine assembly. The proposed method is verified with simulation results that show the efficacy of the controller in extracting power from the turbine while maintaining the speed at the desired level.

  12. Cleaning the Produced Water in Offshore Oil Production by Using Plant-wide Optimal Control Strategy

    DEFF Research Database (Denmark)

    Yang, Zhenyu; Pedersen, Simon; Løhndorf, Petar Durdevic

    2014-01-01

    To clean the produced water is always a challenging critical issue in the offshore oil & gas industry. By employing the plant-wide control technology, this paper discussed the opportunity to optimize the most popular hydrocyclone-based Produced Water Treatment (PWT) system. The optimizations...... of the efficiency control of the de-oiling hydrocyclone and the water level control of the upstream separator, are discussed and formulated. Some of our latest research results on the analysis and control of slugging flows in production well-pipeline-riser systems are also presented. The ultimate objective...... of this research is to promote a technical breakthrough in the PWT control design, which can lead to the best environmental protection in the oil & gas production, without sacrificing the production capability and production costs....

  13. Geomorphological control of water tables in a blanket peat landscape: implications for carbon cycling

    Science.gov (United States)

    Allott, Tim; Evans, Martin; Lindsay, John; Agnew, Clive; Freer, Jim

    2010-05-01

    Water tables are an important control on carbon cycling and rates of carbon sequestration in peatland systems, and water table depth is therefore a key parameter in carbon models for blanket peat systems. Although there is a wide literature on blanket peat hydrology, including studies which specifically evaluate water table conditions, detailed data on water table behaviour and variability at the landscape scale are sparse. In particular, many British blanket peats are affected by gully erosion and this has been generally assumed to influence water table conditions. However, there has been limited evaluation of this geomomorphological control on peatland water tables. This paper presents results from a project which evaluated water table conditions in the blanket peatlands of the Peak District National Park, UK. A key aim was to quantify the impact of gully erosion on peatland water tables. A detailed programme of water table monitoring was undertaken during 2008/09, involving regular measurements of water table depth in over 530 dipwells at 19 sites across the 47 km2 peatland landscape of the Kinder Scout / Bleaklow area. This included a campaign of regular, simultaneous water table measurements from clusters of dipwells at the main sites, supplemented by continuous (hourly) water table monitoring in selected dipwells. It also included studies to evaluate within-site variation in water table conditions and local water table drawdown effects associated with gully erosion. Results indicate that gully erosion causes water table drawdown through two distinct processes. The first is local water table drawdown immediately adjacent to erosion gullies. This effect is restricted to a zone within 2 m of gully edges, and water tables within the gully edge drawdown zone are approximately 200 mm lower than in the adjacent peatland. The second effect is a more general water table lowering at eroded sites, with median water table depths at heavily eroded sites up to 300 mm lower

  14. 76 FR 39091 - San Luis Obispo Flood Control and Water Conservation District; Notice of Effectiveness of Surrender

    Science.gov (United States)

    2011-07-05

    ... Energy Regulatory Commission San Luis Obispo Flood Control and Water Conservation District; Notice of... for a Conduit Hydroelectric Project \\1\\ to the San Luis Obispo Flood Control and Water Conservation...\\ San Luis Obispo Flood Control and Water Conservation District, 17 FERC ] 62,113 (1981). On October...

  15. Hydrological forecast of maximal water level in Lepenica river basin and flood control measures

    Directory of Open Access Journals (Sweden)

    Milanović Ana

    2006-01-01

    Full Text Available Lepenica river basin territory has became axis of economic and urban development of Šumadija district. However, considering Lepenica River with its tributaries, and their disordered river regime, there is insufficient of water for water supply and irrigation, while on the other hand, this area is suffering big flood and torrent damages (especially Kragujevac basin. The paper presents flood problems in the river basin, maximum water level forecasts, and flood control measures carried out until now. Some of the potential solutions, aiming to achieve the effective flood control, are suggested as well.

  16. Use of fluid injection of Krylamin D for control of water influx to underground workings

    Energy Technology Data Exchange (ETDEWEB)

    Postawa, J.; Stryczek, S.; Rakoczy, W.

    1987-05-01

    Water influx to a 270 m deep mine roadway in the Jaworzno black coal mine is associated with a tectonic fault. Injection of Krylamin D urea-formaldehyde resin was used to control water influx. Injection boreholes, 42 mm in diameter, were drilled perpendicular to the roadway axis. Resin consumption rate ranged from 50-150 dm/sup 3/ in coal to 30-80 dm/sup 3/ in shales. About 5 t of resin were used for water influx control in a 5.0 m long roadway section. Resin injection equipment and distribution of injection boreholes are discussed.

  17. An arduino based control system for a brackish water desalination plant

    Science.gov (United States)

    Caraballo, Ginna

    Water scarcity for agriculture is one of the most important challenges to improve food security worldwide. In this thesis we study the potential to develop a low-cost controller for a small scale brackish desalination plant that consists of proven water treatment technologies, reverse osmosis, cation exchange, and nanofiltration to treat groundwater into two final products: drinking water and irrigation water. The plant is powered by a combination of wind and solar power systems. The low-cost controller uses Arduino Mega, and Arduino DUE, which consist of ATmega2560 and Atmel SAM3X8E ARM Cortex-M3 CPU microcontrollers. These are widely used systems characterized for good performance and low cost. However, Arduino also requires drivers and interfaces to allow the control and monitoring of sensors and actuators. The thesis explains the process, as well as the hardware and software implemented.

  18. Water-related environmental control requirements at municipal solid waste-to-energy conversion facilities

    Energy Technology Data Exchange (ETDEWEB)

    Young, J C; Johnson, L D

    1980-09-01

    Water use and waste water production, water pollution control technology requirements, and water-related limitations to their design and commercialization are identified at municipal solid waste-to-energy conversion systems. In Part I, a summary of conclusions and recommendations provides concise statements of findings relative to water management and waste water treatment of each of four municipal solid waste-to-energy conversion categories investigated. These include: mass burning, with direct production of steam for use as a supplemental energy source; mechanical processing to produce a refuse-derived fuel (RDF) for co-firing in gas, coal or oil-fired power plants; pyrolysis for production of a burnable oil or gas; and biological conversion of organic wastes to methane. Part II contains a brief description of each waste-to-energy facility visited during the subject survey showing points of water use and wastewater production. One or more facilities of each type were selected for sampling of waste waters and follow-up tests to determine requirements for water-related environmental controls. A comprehensive summary of the results are presented. (MCW)

  19. Effects of Several Natural Macromolecules on the Stability and Controlled Release Properties of Water-in-Oil-in-Water Emulsions.

    Science.gov (United States)

    Li, Jinlong; Shi, Yiheng; Zhu, Yunping; Teng, Chao; Li, Xiuting

    2016-05-18

    Water-in-oil-in-water (W/O/W) emulsions are effective vehicles for embedding application of active compounds but limited by their thermodynamic instability and rapid release properties. The present study added bovine serum albumin, whey protein isolate, whey protein hydrolysate, sodium caseinate, carboxymethylcellulose sodium, fish gelatin, apple pectin, gum arabic, ι-carrageenan, and hydroxypropyl chitosan separately to the internal or external aqueous phase to investigate their effects on the physical stabilities and controlled release properties of W/O/W emulsions. The effects of the natural macromolecules in the internal and external aqueous phases were different and depended upon the macromolecule structure and its mass fraction. The addition of the natural macromolecule strengthened the interfaces of emulsions, which improved the physical stability. The natural macromolecules that improved the stability often did not improve controlled release. Therefore, the balance between these properties needs to be considered when adding natural macromolecules to a W/O/W emulsion.

  20. Local Adaptive Control of Solar Photovoltaics and Electric Water Heaters for Real-time Grid Support

    DEFF Research Database (Denmark)

    Bhattarai, Bishnu Prasad; Mendaza, Iker Diaz de Cerio; Bak-Jensen, Birgitte

    2016-01-01

    , such as electric vehicles, electric water heaters (EWHs) etc. An adaptive control using only local measurements for the EWHs and PVs is proposed in this study to alleviate OV as well as UV issues. The adaptive control is designed such that it monitors the voltage at the point of connection and adjusts active...

  1. Air dehumidification by membrane with cold water for manned spacecraft environmental control

    Directory of Open Access Journals (Sweden)

    Shang Yonghong

    2017-01-01

    Full Text Available The traditional condensation dehumidification method requires additional gas-liquid separation and water recovery process in the manned spacecraft humidity control system, which would increase weight and complexity of systems. A new membrane dehumidification with cold water is proposed, which uses water vapor partial pressure difference to promote water vapor transmembrane mass transfer for dehumidification. The permeability of the membrane was measured and the experimental results agree well with the theoretical calculations. Based on the simulation of dehumidification process of cold water-membrane, the influence of module structure and working condition on dehumidification performance was analyzed, which provided reference for the design of membrane module construct. It can be seen from the simulation and experiments that the cold water-membrane dehumidification can effectively reduce the thermal load of the manned spacecraft.

  2. Zeta potential in oil-water-carbonate systems and its impact on oil recovery during controlled salinity water-flooding

    Science.gov (United States)

    Jackson, Matthew D.; Al-Mahrouqi, Dawoud; Vinogradov, Jan

    2016-11-01

    Laboratory experiments and field trials have shown that oil recovery from carbonate reservoirs can be increased by modifying the brine composition injected during recovery in a process termed controlled salinity water-flooding (CSW). However, CSW remains poorly understood and there is no method to predict the optimum CSW composition. This work demonstrates for the first time that improved oil recovery (IOR) during CSW is strongly correlated to changes in zeta potential at both the mineral-water and oil-water interfaces. We report experiments in which IOR during CSW occurs only when the change in brine composition induces a repulsive electrostatic force between the oil-brine and mineral-brine interfaces. The polarity of the zeta potential at both interfaces must be determined when designing the optimum CSW composition. A new experimental method is presented that allows this. Results also show for the first time that the zeta potential at the oil-water interface may be positive at conditions relevant to carbonate reservoirs. A key challenge for any model of CSW is to explain why IOR is not always observed. Here we suggest that failures using the conventional (dilution) approach to CSW may have been caused by a positively charged oil-water interface that had not been identified.

  3. Environmental controls on the spatial variability of soil water dynamics in a small watershed

    Science.gov (United States)

    Hu, Wei; Chau, Henry Wai; Qiu, Weiwen; Si, Bingcheng

    2017-08-01

    Soil water content (SWC) in the root zone is controlled by a suite of environmental variables. Complication arises from the cross-correlation between these environmental variables. Therefore, there is still a poor understanding on the controls of root zone SWC dynamics due, in part, to a lack of an appropriate method to untangle the controls. The objective of this study was to reveal the dominant controls of root zone soil water dynamics in a small watershed using an appropriate method based on empirical orthogonal function (EOF). For this purpose, SWC of 0-0.8 m layer in a small watershed on the Chinese Loess Plateau was used. The space-variant temporal anomaly (Rtn) of SWC, which is responsible for the spatial variability of soil water dynamics, was decomposed using the EOF. Results indicated that 86% of the total variations of Rtn were explained by three significant spatial structures (EOFs). Sand content and grass yield dominated the EOF1 of Rtn and elevation and aspect dominated EOF2 and EOF3 of Rtn , respectively. Moreover, their effects on soil water dynamics were time-dependent. The EOF analysis showed that three independent groups of factors (i.e., soil and vegetation dominated earth surface condition, elevation related near surface air humidity, and aspect regulated energy input) may drive the variability in soil water dynamics. Traditional correlation analysis, however, indicated that SWC was greater at higher elevation and sun-facing slopes, which distorted the soil water dynamics controls. Although original SWC-based partial correlation basically supported our findings, the results highly depended on the controlling factors selected. This study implied that Rtn rather than original SWC should be preferred for understanding soil water dynamics controls.

  4. A rapid approach to rational water pollution control strategies.

    Science.gov (United States)

    Economopoulos, A P

    1996-10-01

    The formulation of rational wastewater control strategies is becoming increasingly important in many countries where, exploding urbanization, industrialization and/or tourism, often combined with improved standards of living and better awareness of the environmental problems, are resulting in enlarged pollution problems, but also in the availability of expanding financial resources for environmental protection. However, more often than one tends to believe, lack of planning, or planning with limited understanding of the principles involved, has resulted in solutions that are both expensive and incapable of addressing the key problems.As rigorous planning is extremely resource intensive, and for this reason impractical for most study areas, the development of a much simplified analysis procedure, capable of generating rational, near-optimum, strategies and detailed action programs, is required, if proper environmental management is to be widely practiced.In an effort to achieve the above objectives, a systems analysis approach is selected as the most suitable at rationalizing the allocation of available resources and at producing detailed action programs that promote implementation. In the context of this approach, new, easy to use models have been developed, while others, have been selected, adapted and streamlined in their use. The entire problem analysis and strategy synthesis procedures have thus been simplified and defined to a degree appropriate for widespread use, and the resultant procedure is actively promoted by WHO and UNEP.

  5. Biofouling of Water Treatment Membranes: A Review of the Underlying Causes, Monitoring Techniques and Control Measures

    Directory of Open Access Journals (Sweden)

    Felicity A. Roddick

    2012-11-01

    Full Text Available Biofouling is a critical issue in membrane water and wastewater treatment as it greatly compromises the efficiency of the treatment processes. It is difficult to control, and significant economic resources have been dedicated to the development of effective biofouling monitoring and control strategies. This paper highlights the underlying causes of membrane biofouling and provides a review on recent developments of potential monitoring and control methods in water and wastewater treatment with the aim of identifying the remaining issues and challenges in this area.

  6. Efficacy of highly bioavailable zinc from fortified water: a randomized controlled trial in rural Beninese children.

    Science.gov (United States)

    Galetti, Valeria; Kujinga, Prosper; Mitchikpè, Comlan Evariste S; Zeder, Christophe; Tay, Fabian; Tossou, Félicien; Hounhouigan, Joseph D; Zimmermann, Michael B; Moretti, Diego

    2015-11-01

    Zinc deficiency and contaminated water are major contributors to diarrhea in developing countries. Food fortification with zinc has not shown clear benefits, possibly because of low zinc absorption from inhibitory food matrices. We used a novel point-of-use water ultrafiltration device configured with glass zinc plates to produce zinc-fortified, potable water. The objective was to determine zinc bioavailability from filtered water and the efficacy of zinc-fortified water in improving zinc status. In a crossover balanced study, we measured fractional zinc absorption (FAZ) from the zinc-fortified water in 18 healthy Swiss adults using zinc stable isotopes and compared it with zinc-fortified maize porridge. We conducted a 20-wk double-blind randomized controlled trial (RCT) in 277 Beninese school children from rural settings who were randomly assigned to receive a daily portion of zinc-fortified filtered water delivering 2.8 mg Zn (Zn+filter), nonfortified filtered water (Filter), or nonfortified nonfiltered water (Pump) from the local improved supply, acting as the control group. The main outcome was plasma zinc concentration (PZn), and the 3 groups were compared by using mixed-effects models. Secondary outcomes were prevalence of zinc deficiency, diarrhea prevalence, and growth. Geometric mean (-SD, +SD) FAZ was 7-fold higher from fortified water (65.9%; 42.2, 102.4) than from fortified maize (9.1%; 6.0, 13.7; P diarrhea or growth, but our study did not have the duration and power to detect such effects. Consumption of filtered water fortified with a low dose of highly bioavailable zinc is an effective intervention in children from rural African settings. Large community-based trials are needed to assess the effectiveness of zinc-fortified filtered water on diarrhea and growth. These trials were registered at clinicaltrials.gov as NCT01636583 and NCT01790321. © 2015 American Society for Nutrition.

  7. Design, analysis, and interpretation of field quality-control data for water-sampling projects

    Science.gov (United States)

    Mueller, David K.; Schertz, Terry L.; Martin, Jeffrey D.; Sandstrom, Mark W.

    2015-01-01

    The process of obtaining and analyzing water samples from the environment includes a number of steps that can affect the reported result. The equipment used to collect and filter samples, the bottles used for specific subsamples, any added preservatives, sample storage in the field, and shipment to the laboratory have the potential to affect how accurately samples represent the environment from which they were collected. During the early 1990s, the U.S. Geological Survey implemented policies to include the routine collection of quality-control samples in order to evaluate these effects and to ensure that water-quality data were adequately representing environmental conditions. Since that time, the U.S. Geological Survey Office of Water Quality has provided training in how to design effective field quality-control sampling programs and how to evaluate the resultant quality-control data. This report documents that training material and provides a reference for methods used to analyze quality-control data.

  8. Effect of Jeju Water on Blood Glucose Levels in Diabetic Patients: A Randomized Controlled Trial

    Directory of Open Access Journals (Sweden)

    Gwanpyo Koh

    2013-01-01

    Full Text Available Jeju water is the groundwater of Jeju Island, a volcanic island located in Republic of Korea. We investigated whether Jeju water improved glycemic control in patients with diabetes. This was a 12-week single-center, double-blind, randomized, and controlled trial. The subjects daily drank a liter of one of three kinds of water: two Jeju waters (S1 and S2 and Seoul tap water (SS. The primary outcome was the proportion of patients in the per-protocol (PP population achieving glycated hemoglobin (HbA1c < 7.0% at week 12. In total, 196 patients were randomized and analyzed in the intention-to-treat (ITT population (66 consuming S1, 63 consuming S2, and 67 consuming SS; 146 patients were considered in the PP population. There were no significant differences in the primary outcomes of the groups consuming S1, S2, or SS. However, the percentage of patients achieving HbA1c < 8% was significantly higher in the S2 group than in the SS group. In the ITT population, the 12-week HbA1c and fructosamine levels were lower in the S1 group than in the SS group and the 4-, 8-, and 12-week fructosamine levels were lower in the S2 group than in the SS group. Although we failed to achieve the primary outcome, it is possible that the Jeju waters improve glycemic control compared with the Seoul tap water in diabetic patients.

  9. Biological control experiment of excess propagation of Cyclops for drinking water security

    Institute of Scientific and Technical Information of China (English)

    LIN Tao; CUI Fu-yi; LIU Dong-mei

    2007-01-01

    Cyclops of zooplankton propagated excessively in eutrophic water body and could not be effectively inactivated by the conventional disinfections process like chlorination due to its stronger resistance to oxidation.In this study,an ecological project was put forward for the excess propagation control of Cyclops by stocking the filter-feeding fishes such as silver carp and bighead carp under the condition of no extaneous nutrient feeding.The results of experiments with different stocking biomass showed that the propagation of Cyclops could be controlled effectively,and the water quality was improved simultaneously by impacting on nutriment level and plankton community structure at proper stocking density of 30 g/m3 of water.The growth of Cyclops may not be effectually controlled with lower biomass of fish(10 g),and the natural food chain relation may be destroyed for Cyclops dying out in water while the intense stocking of 120 g per cubic meter of water.In addition,the high predator pressure may accelerate supplemental rate of nutrients from bottom sediments to water body to add the content of total nitrogen and phosphorus in water.

  10. [GIS and scenario analysis aid to water pollution control planning of river basin].

    Science.gov (United States)

    Wang, Shao-ping; Cheng, Sheng-tong; Jia, Hai-feng; Ou, Zhi-dan; Tan, Bin

    2004-07-01

    The forward and backward algorithms for watershed water pollution control planning were summarized in this paper as well as their advantages and shortages. The spatial databases of water environmental function region, pollution sources, monitoring sections and sewer outlets were built with ARCGIS8.1 as the platform in the case study of Ganjiang valley, Jiangxi province. Based on the principles of the forward algorithm, four scenarios were designed for the watershed pollution control. Under these scenarios, ten sets of planning schemes were generated to implement cascade pollution source control. The investment costs of sewage treatment for these schemes were estimated by means of a series of cost-effective functions; with pollution source prediction, the water quality was modeled with CSTR model for each planning scheme. The modeled results of different planning schemes were visualized through GIS to aid decision-making. With the results of investment cost and water quality attainment as decision-making accords and based on the analysis of the economic endurable capacity for water pollution control in Ganjiang river basin, two optimized schemes were proposed. The research shows that GIS technology and scenario analysis can provide a good guidance to the synthesis, integrity and sustainability aspects for river basin water quality planning.

  11. Improving water management efficiency by using optimization-based control strategies: the Barcelona case study

    OpenAIRE

    2009-01-01

    This paper describes the application of model-based predictive control (MPC) techniques to the flow management in large-scale drinking water networks including a telemetry/telecontrol system. MPC technique is used to generate flow control strategies from the sources to the consumer areas to meet future demands, optimizing performance indexes associated to operational goals such as economic cost, network safety volumes and flow control stability. The designed management strategies are...

  12. Toward city-scale water quality control: building a theory for smart stormwater systems

    Science.gov (United States)

    Kerkez, B.; Mullapudi, A. M.; Wong, B. P.

    2016-12-01

    Urban stormwater systems are rarely designed as actual systems. Rather, it is often assumed that individual Best Management Practices (BMPs) will add up to achieve desired watershed outcomes. Given the rise of BMPs and green infrastructure, we ask: does doing "best" at the local scale guarantee the "best" at the global scale? Existing studies suggest that the system-level performance of distributed stormwater practices may actually adversely impact watersheds by increasing downstream erosion and reducing water quality. Optimizing spatial placement may not be sufficient, however, since precipitation variability and other sources of uncertainty can drive the overall system into undesirable states. To that end, it is also important to control the temporal behavior of the system, which can be achieved by equipping stormwater elements (ponds, wetlands, basins, bioswales, etc.) with "smart" sensors and valves. Rather than building new infrastructure, this permits for existing assets to be repurposed and controlled to adapt to individual storm events. While we have learned how to build and deploy the necessary sensing and control technologies, we do not have a framework or theory that combines our knowledge of hydrology, hydraulics, water quality and control. We discuss the development of such a framework and investigate how existing water domain knowledge can be transferred into a system-theoretic context to enable real-time, city-scale stormwater control. We apply this framework to water quality control in an urban watershed in southeast Michigan, which has been heavily instrumented and retrofitted for control over the past year.

  13. An Integrated Model for Simulating Regional Water Resources Based on Total Evapotranspiration Control Approach

    Directory of Open Access Journals (Sweden)

    Jianhua Wang

    2014-01-01

    Full Text Available Total evapotranspiration and water consumption (ET control is considered an efficient method for water management. In this study, we developed a water allocation and simulation (WAS model, which can simulate the water cycle and output different ET values for natural and artificial water use, such as crop evapotranspiration, grass evapotranspiration, forest evapotranspiration, living water consumption, and industry water consumption. In the calibration and validation periods, a “piece-by-piece” approach was used to evaluate the model from runoff to ET data, including the remote sensing ET data and regional measured ET data, which differ from the data from the traditional hydrology method. We applied the model to Tianjin City, China. The Nash-Sutcliffe efficiency (Ens of the runoff simulation was 0.82, and its regression coefficient R2 was 0.92. The Nash-Sutcliffe Efficiency (Ens of regional total ET simulation was 0.93, and its regression coefficient R2 was 0.98. These results demonstrate that ET of irrigation lands is the dominant part, which accounts for 53% of the total ET. The latter is also a priority in ET control for water management.

  14. EFFECT OF GROUNDWATER TABLE CONTROL ON WATER SAVING IRRIGATION STRATEGIES IN THE QINGTONGXIA IRRIGATION DISTRICT

    Institute of Scientific and Technical Information of China (English)

    WANG Xiu-gui; HOLLANDERS P. H. J.

    2004-01-01

    This paper focuses on the analysis of the effects of groundwater table control under different irrigation water amounts on the water and salinity balance and on crop yield. Two experimental areas, the Pingluo and Huinong experimental sites, were selected to collect the required data.The agro-hydrological model Soil-Water Atmosphere-Plant(SWAP) was used to analyse the water flows and salt transport processes for different groundwater levels and irrigation scenarios. Six scenarios, which resulted from different groundwater table regimes combined with different irrigation amounts, were simulated. The results show that high groundwater tables due to the excessive irrigation are the main cause of the large amount of drainage water and low crop yield;reducing irrigation water without a lower groundwater table will not lead to a large reduction of the drainage water, and will reduce the crop yield even more; to lower the groundwater table is a good measure to control the drainage water and increase crop yield.

  15. The controllability analysis of the purification system for heavy water reactors

    Energy Technology Data Exchange (ETDEWEB)

    Lee, K. D.; Cho, B. H.; Shin, C. H.; Kim, S. H. [KEPRI, Taejon (Korea, Republic of); Lee, Y. K.; Kim, K. U. [KHNP, Kyungju (Korea, Republic of)

    2001-10-01

    The heavy water reactor such as Wolsung No.1 and No.2 has a purification system to purify the reactor coolant. The control system regulates the coolant temperature to protect the ion exchanger. After the fuel exchanges of operating plant, the increase of the coolant pressure makes the purification temperature control difficult. In this paper, the controllability of the control dynamics of the purification system was analysed and the optimal parameters were proposed. To reduce the effects of the flow disturbance, the feedforward control structure was proposed and analysed.

  16. Building America Case Study: Control Retrofits for Multifamily Domestic Hot Water Recirculation Systems, Brooklyn, New York

    Energy Technology Data Exchange (ETDEWEB)

    2016-12-01

    Domestic hot water (DHW) heating is the second largest energy end use in U.S. buildings, exceeded only by space conditioning. Recirculation systems consisting of a pump and piping loop(s) are commonly used in multifamily buildings to reduce wait time for hot water at faucets; however, constant pumping increases energy consumption by exposing supply and return line piping to continuous heat loss, even during periods when there is no demand for hot water. In this study, ARIES installed and tested two types of recirculation controls in a pair of buildings in order to evaluate their energy savings potential. Demand control, temperature modulation controls, and the simultaneous operation of both were compared to the baseline case of constant recirculation. Additionally, interactive effects between DHW control fuel reductions and space conditioning (heating and cooling) were estimated in order to make more realistic predictions of the payback and financial viability of retrofitting DHW systems with these controls. Results showed that DHW fuel consumption reduced by 7 percent after implementing the demand control technique, 2 percent after implementing temperature modulation, and 15 percent after implementing demand control and temperature modulation techniques simultaneously; recirculation pump runtime was reduced to 14 minutes or less per day. With space heating and cooling interactions included, the estimated annual cost savings were 8 percent, 1 percent, and 14 percent for the respective control techniques. Possible complications in the installation, commissioning and operation of the controls were identified and solutions offered.

  17. Control Strategies to Reduce the Energy Consumption of Central Domestic Hot Water Systems

    Energy Technology Data Exchange (ETDEWEB)

    Dentz, Jordan; Ansanelli, Eric; Henderson, Hugh; Varshney, Kapil

    2016-06-03

    Domestic hot water (DHW) heating is the second largest energy end use in U.S. buildings, exceeded only by space conditioning. Recirculation systems consisting of a pump and piping loop(s) are commonly used in multifamily buildings to reduce wait time for hot water at faucets; however, constant pumping increases energy consumption by exposing supply and return line piping to continuous heat loss, even during periods when there is no demand for hot water. In this study, ARIES installed and tested two types of recirculation controls in a pair of buildings in order to evaluate their energy savings potential. Demand control, temperature modulation controls, and the simultaneous operation of both were compared to the baseline case of constant recirculation. Additionally, interactive effects between DHW control fuel reductions and space conditioning (heating and cooling) were estimated in order to make more realistic predictions of the payback and financial viability of retrofitting DHW systems with these controls. Results showed that DHW fuel consumption reduced by 7% after implementing the demand control technique, 2% after implementing temperature modulation, and 15% after implementing demand control and temperature modulation techniques simultaneously; recirculation pump runtime was reduced to 14 minutes or less per day. With space heating and cooling interactions included, the estimated annual cost savings were 8%, 1%, and 14% for the respective control techniques. Possible complications in the installation, commissioning and operation of the controls were identified and solutions offered.

  18. Control Strategies to Reduce the Energy Consumption of Central Domestic Hot Water Systems

    Energy Technology Data Exchange (ETDEWEB)

    Dentz, Jordan [The Levy Partnership, Inc., New York, NY (United States). Advanced Residential Integrated Energy Solutions; Ansanelli, Eric [The Levy Partnership, Inc., New York, NY (United States). Advanced Residential Integrated Energy Solutions; Henderson, Hugh [The Levy Partnership, Inc., New York, NY (United States). Advanced Residential Integrated Energy Solutions; Varshney, Kapil [The Levy Partnership, Inc., New York, NY (United States). Advanced Residential Integrated Energy Solutions

    2016-06-23

    Domestic hot water (DHW) heating is the second largest energy end use in U.S. buildings, exceeded only by space conditioning. Recirculation systems consisting of a pump and piping loop(s) are commonly used in multifamily buildings to reduce wait time for hot water at faucets; however, constant pumping increases energy consumption by exposing supply and return line piping to continuous heat loss, even during periods when there is no demand for hot water. In this study, ARIES installed and tested two types of recirculation controls in a pair of buildings in order to evaluate their energy savings potential. Demand control, temperature modulation controls, and the simultaneous operation of both were compared to the baseline case of constant recirculation. Additionally, interactive effects between DHW control fuel reductions and space conditioning (heating and cooling) were estimated in order to make more realistic predictions of the payback and financial viability of retrofitting DHW systems with these controls. Results showed that DHW fuel consumption reduced by 7% after implementing the demand control technique, 2% after implementing temperature modulation, and 15% after implementing demand control and temperature modulation techniques simultaneously; recirculation pump runtime was reduced to 14 minutes or less per day. With space heating and cooling interactions included, the estimated annual cost savings were 8%, 1%, and 14% for the respective control techniques. Possible complications in the installation, commissioning and operation of the controls were identified and solutions offered.

  19. Water-based exercise in COPD with physical comorbidities: a randomised controlled trial.

    Science.gov (United States)

    McNamara, Renae J; McKeough, Zoe J; McKenzie, David K; Alison, Jennifer A

    2013-06-01

    Land-based exercise is often difficult for people with chronic obstructive pulmonary disease (COPD) who have coexisting obesity or musculoskeletal or neurological conditions. This randomised controlled trial aimed to determine the effectiveness of water-based exercise training in improving exercise capacity and quality of life compared to land-based exercise training and control (no exercise) in people with COPD and physical comorbidities. Participants referred to pulmonary rehabilitation were randomly allocated to a water-based exercise, land-based exercise or the control group. The two exercise groups trained for 8 weeks, completing three sessions per week. 45 out of 53 participants (mean ± SD age 72 ± 9 years; forced expiratory volume in 1 s 59 ± 15% predicted) completed the study. Compared to controls, water-based exercise training significantly increased 6-min walking distance, incremental and endurance shuttle walk distances, and improved Chronic Respiratory Disease Questionnaire (CRDQ) dyspnoea and fatigue. Compared to land-based exercise training, water-based exercise training significantly increased incremental shuttle walk distance (mean difference 39 m, 95% CI 5-72 m), endurance shuttle walk distance (mean difference 228 m, 95% CI 19-438 m) and improved CRDQ fatigue. Water-based exercise training was significantly more effective than land-based exercise training and control in increasing peak and endurance exercise capacity and improving aspects of quality of life in people with COPD and physical comorbidities.

  20. Flint Water Crisis Caused By Interrupted Corrosion Control: Investigating "Ground Zero" Home.

    Science.gov (United States)

    Pieper, Kelsey J; Tang, Min; Edwards, Marc A

    2017-02-21

    Flint, Michigan switched to the Flint River as a temporary drinking water source without implementing corrosion control in April 2014. Ten months later, water samples collected from a Flint residence revealed progressively rising water lead levels (104, 397, and 707 μg/L) coinciding with increasing water discoloration. An intensive follow-up monitoring event at this home investigated patterns of lead release by flow rate-all water samples contained lead above 15 μg/L and several exceeded hazardous waste levels (>5000 μg/L). Forensic evaluation of exhumed service line pipes compared to water contamination "fingerprint" analysis of trace elements, revealed that the immediate cause of the high water lead levels was the destabilization of lead-bearing corrosion rust layers that accumulated over decades on a galvanized iron pipe downstream of a lead pipe. After analysis of blood lead data revealed spiking lead in blood of Flint children in September 2015, a state of emergency was declared and public health interventions (distribution of filters and bottled water) likely averted an even worse exposure event due to rising water lead levels.

  1. Fire Source Accessibility of Water Mist Fire Suppression Improvement through Flow Method Control

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Jun Ho; Kim, Hyeong Taek; Kim, Yun Jung; Park, Mun Hee [KHNP CRI, Daejeon (Korea, Republic of)

    2013-10-15

    Recently, nuclear power plants set CO{sub 2} fire suppression system. However it is hard to establish and to maintain and it also has difficulties performing function test. Therefore, it needs to develop a new fire suppression system to replace the existing CO{sub 2} fire suppression systems in nuclear power plant. In fact, already, there exist alternatives - gas fire suppression system or clean fire extinguishing agent, but it is hard to apply because it requires a highly complicated plan. However, water mist fire suppression system which has both water system and gas system uses small amount of water and droplet, so it is excellent at oxygen displacement and more suitable for nuclear power plant because it can avoid second damage caused by fire fighting water. This paper explains about enclosure effect of water mist fire suppression. And it suggests a study direction about water mist fire source approach improvement and enclosure effect improvement, using flow method control of ventilation system. Water mist fire suppression can be influenced by various variable. And flow and direction of ventilation system are important variable. Expectations of the plan for more fire source ventilation system is as in the following. It enhances enclosure effects of water mists, so it improves extinguish performance. Also the same effect as a inert gas injection causes can be achieved. Lastly, it is considered that combustible accessibility of water mists will increase because of descending air currents.

  2. Controls on Surface Water Chemistry in the Upper Merced River Basin, Yosemite National Park, California

    Science.gov (United States)

    Clow, David W.; Alisa Mast, M.; Campbell, Donald H.

    1996-05-01

    Surface water draining granitic bedrock in Yosemite National Park exhibits considerable variability in chemical composition, despite the relative homogeneity of bedrock chemistry. Other geological factors, including the jointing and distribution of glacial till, appear to exert strong controls on water composition. Chemical data from three surface water surveys in the upper Merced River basin conducted in August 1981, June 1988 and August 1991 were analysed and compared with mapped geological, hydrological and topographic features to identify the solute sources and processes that control water chemistry within the basin during baseflow. Water at most of the sampling sites was dilute, with alkalinities ranging from 26 to 77 equiv. l-1. Alkalinity was much higher in two subcatchments, however, ranging from 51 to 302 equiv. l-1. Base cations and silica were also significantly higher in these two catchments than in the rest of the watershed. Concentrations of weathering products in surface water were correlated to the fraction of each subcatchment underlain by surficial material, which is mostly glacial till. Silicate mineral weathering is the dominant control on concentrations of alkalinity, silica and base cations, and ratios of these constituents in surface water reflect the composition of local bedrock. Chloride concentrations in surface water samples varied widely, ranging from Happy Isles gauge from 1968 to 1990 was 26 equiv. l-1, which was five times higher than in atmospheric deposition (4-5 equiv. l-1), suggesting that a source of chloride exists within the watershed. Saline groundwater springs, whose locations are probably controlled by vertical jointing in the bedrock, are the most likely source of the chloride. Sulphate concentrations varied much less than most other solutes, ranging from 3 to 14 equiv. l-1. Concentrations of sulphate in quarterly samples collected at the watershed outlet also showed relatively little variation, suggesting that sulphate may

  3. Cyanobacteria and cyanotoxins: need for their control in water for human consumption

    Directory of Open Access Journals (Sweden)

    Ana Mª Cameán Fernández

    2005-12-01

    Full Text Available Cyanobacterial waterblooms are becoming an important water quality problem in many countries in the world, as a result of its hepatotoxic and neurotoxic cyanotoxins production, which make these toxins a health risk. Microcystins (MC are the most frequent cyanotoxins detected on superficial freshwaters. In the present work, toxic risks derived from exposure to MC have been revised, mainly due to the consumption of contaminated waters. This fact makes necessary to perform control and monitoring programs.

  4. Construction of Genetically Engineered Streptococcus gordonii Strains to Provide Control in QPCR Assays for Assessing Microbiological Quality in Recreational Water.

    Science.gov (United States)

    Quantitative PCR (QPCR) methods for beach monitoring by estimating abundance of Enterococcus spp. in recreational waters use internal, positive controls which address only the amplification of target DNA. In this study two internal, positive controls were developed to control for...

  5. Identification and robust water level control of horizontal steam generators using quantitative feedback theory

    Energy Technology Data Exchange (ETDEWEB)

    Safarzadeh, O., E-mail: O_Safarzadeh@sbu.ac.ir [Shahid Beheshti University, P.O. Box: 19839-63113, Tehran (Iran, Islamic Republic of); Khaki-Sedigh, A. [K. N. Toosi University of Technology, Tehran (Iran, Islamic Republic of); Shirani, A.S. [Shahid Beheshti University, P.O. Box: 19839-63113, Tehran (Iran, Islamic Republic of)

    2011-09-15

    Highlights: {yields} A robust water level controller for steam generators (SGs) is designed based on the Quantitative Feedback Theory. {yields} To design the controller, fairly accurate linear models are identified for the SG. {yields} The designed controller is verified using a developed novel global locally linear neuro-fuzzy model of the SG. {yields} Both of the linear and nonlinear models are based on the SG mathematical thermal-hydraulic model developed using the simulation computer code. {yields} The proposed method is easy to apply and guarantees desired closed loop performance. - Abstract: In this paper, a robust water level control system for the horizontal steam generator (SG) using the quantitative feedback theory (QFT) method is presented. To design a robust QFT controller for the nonlinear uncertain SG, control oriented linear models are identified. Then, the nonlinear system is modeled as an uncertain linear time invariant (LTI) system. The robust designed controller is applied to the nonlinear plant model. This nonlinear model is based on a locally linear neuro-fuzzy (LLNF) model. This model is trained using the locally linear model tree (LOLIMOT) algorithm. Finally, simulation results are employed to show the effectiveness of the designed QFT level controller. It is shown that it will ensure the entire designer's water level closed loop specifications.

  6. Anopheles culicifacies breeding in Sri Lanka and options for control through water management

    DEFF Research Database (Denmark)

    Konradsen, F; Matsuno, Y; Amerasinghe, F P

    1998-01-01

    This paper assesses the options for control of malaria vectors through different water management practices in a natural stream in Sri Lanka. The association between water level in the stream and breeding of the immature stages of the primary vector Anopheles culicifacies was investigated...... and the feasibility of using existing irrigation infrastructure to reduce the breeding potential discussed. The most feasible option would be to implement a management routine where water is released periodically from an upstream reservoir to reduce the number of breeding sites downstream. This study indicates...... that by regulating the water level above 20 cm in the stream throughout the dry season the breeding of A. culicifacies could be significantly reduced. The intervention would have only limited impact on the water lost for agriculture and the management input would be minimal. However, for the intervention to work...

  7. Improved Water Network Macroscopic Model Utilising Auto-Control Adjusting Valve by PLS

    Institute of Scientific and Technical Information of China (English)

    LI Xia; ZHAO Xinhua; WANG Xiaodong

    2005-01-01

    In order to overcome the low precision and weak applicability problems of the current municipal water network state simulation model, the water network structure is studied. Since the telemetry system has been applied increasingly in the water network, and in order to reflect the network operational condition more accurately, a new water network macroscopic model is developed by taking the auto-control adjusting valve opening state into consideration. Then for highly correlated or collinear independent variables in the model, the partial least squares (PLS) regression method provides a model solution which can distinguish between the system information and the noisy data. Finally, a hypothetical water network is introduced for validating the model. The simulation results show that the relative error is less than 5.2%, indicating that the model is efficient and feasible, and has better generalization performance.

  8. Advancements in oxygen generation and humidity control by water vapor electrolysis

    Science.gov (United States)

    Heppner, D. B.; Sudar, M.; Lee, M. C.

    1988-01-01

    Regenerative processes for the revitalization of manned spacecraft atmospheres or other manned habitats are essential for realization of long-term space missions. These processes include oxygen generation through water electrolysis. One promising technique of water electrolysis is the direct conversion of the water vapor contained in the cabin air to oxygen. This technique is the subject of the present program on water vapor electrolysis development. The objectives were to incorporate technology improvements developed under other similar electrochemical programs and add new ones; design and fabricate a mutli-cell electrochemical module and a testing facility; and demonstrate through testing the improvements. Each aspect of the water vapor electrolysis cell was reviewed. The materials of construction and sizing of each element were investigated analytically and sometime experimentally. In addition, operational considerations such as temperature control in response to inlet conditions were investigated. Three specific quantitative goals were established.

  9. Role of water quality assessments in hospital infection control: Experience from a new oncology center in eastern India

    Directory of Open Access Journals (Sweden)

    Ramkrishna Bhalchandra

    2014-01-01

    Full Text Available Water quality assessment and timely intervention are essential for health. Microbiology, total dissolved solids (TDS and free residual chlorine were measured for water quality maintenance in an oncology center in India. Impact of these interventions over a period of 22 months has been demonstrated with four cardinal events. Pseudomonas in hospital water was controlled by adequate chlorination, whereas high TDS in the central sterile supply department water was corrected by the installation of electro-deionization plant. Contaminated bottled water was replaced using quality controlled hospital supply. Timely detection and correction of water-related issues, including reverse osmosis plant was possible through multi-faceted approach to water quality.

  10. Water Pollution and Control Measures%水污染与治理措施

    Institute of Scientific and Technical Information of China (English)

    李秉龙

    2016-01-01

    近年来,伴随着工业进程的不断发展,各类工业废水、废气、废弃物等急剧增加。大气、海洋、河流污染日益严重,对于水污染水及主要污染物排放的总体情况及各地区的实际情况,对生活污水、工业废水、农田排水以及畜禽养殖等污染提出了相应的治理措施。%In recent years, with the continuous development of industrial process and rapid increase of various industrial waste water, waste gas and waste and occasional occurrence of serious pollution accidents, the atmosphere, ocean and river have increasingly been polluted, the control of water pollution is vital, only when we do a good job in water pollution control and ensure the water security can the sustainable development be realized. The paper summarizes the total conditions of polluted water in our country and major pollutant discharge and practical conditions in various regions, and puts forwards the corresponding control measures of sanitary sewage, industrial waste water, farm drainage and livestock pollutions.

  11. Independent Design of Multivariable Controllers for A 24-Tray Separating Mixture of Methanol and Water

    Directory of Open Access Journals (Sweden)

    Elham Sareban

    2015-03-01

    Full Text Available Most industrial processes are characterized with large uncertainties. To deal with these kinds of processes and achieve fast and accurate control in a stable fashion, the multiple-model control methods have been demonstrated to be very effective. It is difficult to build the precise mathematic model of the object and to accurately control the object with the traditional control methods. This paper applies H-infinity robust control strategies to a 24-tray separating a mixture of methanol and water. The idea has favorable controls on control targets (rise time, settling time, overshoot and undershoot, the interaction between input and output and help on stability of the system output. Then in order to show that the proposed controller affords a good robust performance consistently we have implemented four controllers.Performance analysis of the H-infinity robust controller, Model Predictive Control (MPC, conventional PID controller and also LQG/LTR has been done using MATLAB. The comparison of various time domain parameters was done to prove that the H-Infinity robust controller has best time characteristics and in face with uncertainties has better reacts as compared to other controllers. Beside this, MPC controller has satisfied result in robust stability.

  12. A real-time control framework for urban water reservoirs operation

    Science.gov (United States)

    Galelli, S.; Goedbloed, A.; Schwanenberg, D.

    2012-04-01

    Drinking water demand in urban areas is growing parallel to the worldwide urban population, and it is acquiring an increasing part of the total water consumption. Since the delivery of sufficient water volumes in urban areas represents a difficult logistic and economical problem, different metropolitan areas are evaluating the opportunity of constructing relatively small reservoirs within urban areas. Singapore, for example, is developing the so-called 'Four National Taps Strategies', which detects the maximization of water yields from local, urban catchments as one of the most important water sources. However, the peculiar location of these reservoirs can provide a certain advantage from the logistical point of view, but it can pose serious difficulties in their daily management. Urban catchments are indeed characterized by large impervious areas: this results in a change of the hydrological cycle, with decreased infiltration and groundwater recharge, and increased patterns of surface and river discharges, with higher peak flows, volumes and concentration time. Moreover, the high concentrations of nutrients and sediments characterizing urban discharges can cause further water quality problems. In this critical hydrological context, the effective operation of urban water reservoirs must rely on real-time control techniques, which can exploit hydro-meteorological information available in real-time from hydrological and nowcasting models. This work proposes a novel framework for the real-time control of combined water quality and quantity objectives in urban reservoirs. The core of this framework is a non-linear Model Predictive Control (MPC) scheme, which employs the current state of the system, the future discharges furnished by a predictive model and a further model describing the internal dynamics of the controlled sub-system to determine an optimal control sequence over a finite prediction horizon. The main advantage of this scheme stands in its reduced

  13. Integrating water quality modeling with ecological risk assessment for nonpoint source pollution control: A conceptual framework

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Y.D.; McCutcheon, S.C.; Rasmussen, T.C.; Nutter, W.L.; Carsel, R.F.

    1993-01-01

    The historical development of water quality protection goals and strategies in the United States is reviewed. The review leads to the identification and discussion of three components (i.e., management mechanism, environmental investigation approaches, and environmental assessment and criteria) for establishing a management framework for nonpoint source pollution control. Water quality modeling and ecological risk assessment are the two most important and promising approaches to the operation of the proposed management framework. A conceptual framework that shows the general integrative relationships between water quality modeling and ecological risk assessment is presented. (Copyright (c) 1993 IAWQ.)

  14. Cylindrical Water Triboelectric Nanogenerator via Controlling Geometrical Shape of Anodized Aluminum for Enhanced Electrostatic Induction.

    Science.gov (United States)

    Lee, Sukyung; Chung, Jihoon; Kim, Dae Yun; Jung, Jung-Yeul; Lee, Seong Hyuk; Lee, Sangmin

    2016-09-28

    We demonstrate a cylindrical water triboelectric nanogenerator (CW-TENG) that generates sustainable electrical output. The inner surface of the cylinder was patterned into superhydrophobic and hydrophilic parts to control water flow inside the packaged design of CW-TENG. Here, various thicknesses and roughnesses of the superhydrophobic surface, generated using aluminum oxide nanostructures for enhanced electrostatic induction, were measured to obtain the maximum output and superhydrophobicity. Also, we demonstrate the possibility of using a hydrophilic surface for energy harvesting and as a water reservoir in the packaged design.

  15. Water management in cities of the future using emission control strategies for priority hazardous substances

    DEFF Research Database (Denmark)

    Eriksson, Eva; Revitt, D. M.; Ledin, A.

    2011-01-01

    Cities of the future face challenges with respect to the quantity and quality of water resources, and multiple managerial options need to be considered in order to safeguard urban surface water quality. In a recently completed project on “Source Control Options for Reducing Emissions of Priority...... in the results. The selected PPs differ in their uses and environmental fate and therefore accumulate in different urban environmental compartment. To achieve the required reduction in PP levels in urban waters the full implementation of existing EU regulation is essential and appropriate combinations...

  16. Controllability analysis as a pre-selection method for sensor placement in water distribution systems.

    Science.gov (United States)

    Diao, Kegong; Rauch, Wolfgang

    2013-10-15

    Detection of contamination events in water distribution systems is a crucial task for maintaining water security. Online monitoring is considered as the most cost-effective technology to protect against the impacts of contaminant intrusions. Optimization methods for sensor placement enable automated sensor layout design based on hydraulic and water quality simulation. However, this approach results in an excessive computational burden. In this paper we outline the application of controllability analysis as preprocessing method for sensor placement. Based on case studies we demonstrate that the method decreases the number of decision variables for subsequent optimization dramatically to app. 30 to 40 percent.

  17. Influence of Air Humidity and Water Particles on Dust Control Using Ultrasonic Atomization

    Science.gov (United States)

    Okawa, Hirokazu; Nishi, Kentaro; Shindo, Dai; Kawamura, Youhei

    2012-07-01

    The influence of air humidity and water particles on dust control was examined using ultrasonic atomization at 2.4 MHz, an acrylic box (61 L), and four types of ore dust samples: green tuff (4 µm), green tuff (6 µm), kaolin, and silica. It was clearly demonstrated that ultrasonic atomization was effective in raising humidity rapidly. However, at high relative air humidity, the water particles remained stable in the box without changing to water vapor. Ultrasonic atomization was applied to suppress dust dispersion and 40-95% dust reduction was achieved at 83% relative air humidity. Dust dispersion was more effective with ultrasonic atomization than without.

  18. 75 FR 7627 - Notice of Lodging of Proposed Consent Decree Under the Federal Water Pollution Control Act

    Science.gov (United States)

    2010-02-22

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF JUSTICE Notice of Lodging of Proposed Consent Decree Under the Federal Water Pollution Control Act Notice is hereby... requirements of the Federal Water Pollution Control Act (Clean Water Act), 40 CFR part 403 and 33 U.S.C....

  19. A case study of regional catchment water quality modelling to identify pollution control requirements.

    Science.gov (United States)

    Crabtree, B; Seward, A J; Thompson, L

    2006-01-01

    There are four ecologically important river catchments that contain candidate Special Areas of Conservation (cSACs) under the Habitats Directive in the Lake District National Park located in the North of England. These are the rivers Ehen, Kent, Derwent and Eden. For each cSAC, there are defined ecological criteria that include water quality targets to protect the designated species. Stretches of the riverine cSACs in each catchment are failing to meet these and other water quality targets. The Environment Agency commissioned a study of each catchment to provide the underpinning scientific knowledge to allow it to deliver its statutory obligations under the Habitats Directive. SIMCAT river water quality models were produced and used to predict the water quality impacts resulting from a number of water quality planning scenarios aimed at achieving full compliance with the Habitats Directive and other national and EEC water quality targets. The results indicated that further controls on effluent discharges will allow the majority of targets to be met but other sources of pollution will also need to be controlled. The outcome of the study also recognised that water quality improvements alone will not necessarily produce the required improvement to the ecological interest features in each cSAC.

  20. HYDRAULIC CHARACTERISTICS OF BOTTOM UNDERLAY-TYPE PIER FOR WATER-WING CONTROL

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The pier, placed at the outlet of the pressure flow section, is an effective design to deal with the problems of the manufacture and operation of the gates for a discharge tunnel with high water head. It is crucial to control the water-wing, induced by this type of the pier. Through observing the phenomena of the water-wing, the reason of the water-wing inception, i.e., the concave of the flow surface, was presented, and a type of the new pier with bottom underlay was designed. The hydraulic characteristics of the pier, including the variations of the water-wing features, both length and height, with the water head, as well as with the concave depth, and with the height of the bottom underlay, and the variations of the concave depth with the height of the bottom underlay, were investigated by physical model experiments. The results show that the approach of the modification of the concave through the structures with the bottom underlay-type pier is remarkably effective in the water-wing control.

  1. Improved algorithms in the CE-QUAL-W2 water-quality model for blending dam releases to meet downstream water-temperature targets

    Science.gov (United States)

    Rounds, Stewart A.; Buccola, Norman L.

    2015-01-01

    Water-quality models allow water resource professionals to examine conditions under an almost unlimited variety of potential future scenarios. The two-dimensional (longitudinal, vertical) water-quality model CE-QUAL-W2, version 3.7, was enhanced and augmented with new features to help dam operators and managers explore and optimize potential solutions for temperature management downstream of thermally stratified reservoirs. Such temperature management often is accomplished by blending releases from multiple dam outlets that access water of different temperatures at different depths. The modified blending algorithm in version 3.7 of CE-QUAL-W2 allows the user to specify a time-series of target release temperatures, designate from 2 to 10 floating or fixed-elevation outlets for blending, impose minimum and maximum head and flow constraints for any blended outlet, and set priority designations for each outlet that allow the model to choose which outlets to use and how to balance releases among them. The modified model was tested with a variety of examples and against a previously calibrated model of Detroit Lake on the North Santiam River in northwestern Oregon, and the results compared well. These updates to the blending algorithms will allow more complicated dam-operation scenarios to be evaluated somewhat automatically with the model, with decreased need for multiple model runs or preprocessing of model inputs to fully characterize the operational constraints.

  2. High Precision Temperature Control and Analysis of RF Deionized Cooling Water System

    CERN Document Server

    Tsai, Zong-Da; Chen June Rong; Liu, Chen-Yao

    2005-01-01

    Previously, the Taiwan Light Source (TLS) has proven the good beam quality mainly depends on the utility system stability. A serial of efforts were devoted to these studies. Further, a high precision temperature control of the RF deionized cooling water system will be achieved to meet the more critical stability requirement. The paper investigates the mixing mechanism through thermal and flow analysis and verifies the practical influences. A flow mixing mechanism and control philosophy is studied and processed to optimize temperature variation which has been reduced from ±0.1? to ±0.01?. Also, the improvement of correlation between RF performance and water cooling stability will be presented.

  3. Effect of sediment settling on controlling golden mussel invasion in water transfer project

    Science.gov (United States)

    Xu, Mengzhen; Wang, Zhaoyin; Bogen, Jim; Pan, Baozhu

    2013-04-01

    golden mussels by preventing them from filtering food and oxygen from water, and in this way killing them. The attachment density decreased with increased sediment deposition. Golden mussel density decreased by about 70-90% when the sedimentation rate increased by 3-6 times. Therefore, spraying with fine sediment or creating hyper-concentration of sediment water to treat golden mussels before they enter tunnels is recommended as an effective strategy for controlling golden mussel invasion and high-density bio-fouling. Key words: golden mussel invasion; bio-fouling; sediment settling; habitat; controlling strategy

  4. Development of Fuzzy Controller for Water Level in Stream Boiler Tank

    Directory of Open Access Journals (Sweden)

    Surachai Panich

    2010-01-01

    Full Text Available Problem statement: The process control of steam boiler is very popular used in the industrial. The temperature of the water is transferred directly by electrical heater. The pressure will increase based on the changing of the temperature. The purpose of the control is to change the opening set point for the valve when the temperature and pressure in the tank are changed. For this problem, we develop fuzzy algorithm to adjust the optimal percentage of valve open. Approach: In this study, the fuzzy control application was programmed in fuzzy control language in form of the function block using structure control language. The input information consisted of real variables in the form of measurable process variables, as well as set points. And the output variables were real variables in the form of correcting variables. Results: The fuzzy control was developed, which consists of two input variables, the degree of temperature and pressure in boiler tank measured by sensor. For fuzzy system of water level control, the algorithm is basically implemented in form of the MATLAB code. In the experiment, we assumed that the water level would not effect to the temperature and pressure. Conclusion: The research for the development of the fuzzy logic and the model was tested with the step inputs and the changing of the inputs. The whole simulation process was built to test the behavior of the system when the inputs change.

  5. Lung cancer and arsenic exposure in drinking water: a case-control study in northern Chile

    Directory of Open Access Journals (Sweden)

    Catterina Ferreccio

    1998-01-01

    Full Text Available In some Chilean cities, levels of arsenic (As in drinking water reached 800 µg/L between 1950 and 1970, while current levels are 40 µg/L. To evaluate the causal role of this exposure in lung and bladder cancers, we conducted a case-control study in Regions I, II, and III of the country. From 1994 to 1996, cases diagnosed as lung cancer and two hospital controls were entered in the study; one control was a patient with a cancer, while the other was a patient without cancer, both conditions unrelated to As. Controls were matched with cases by age and sex. A standard survey containing questions about residence, employment, health history, was administered to study subjects. Data on As concentrations in water were obtained from records of the municipal water companies. A total of 151 lung cancer cases and 419 controls (167 with cancer and 242 without cancer were enrolled. Median level of lifetime As exposure was significantly higher among cases, with a clear dose-response relationship between mean As exposure levels, with an OR (95% CI of: 1, 1.7 (0.5-5.1, 3.9 (1.2-13.4, 5.5 (2.2-13.5, and 9.0 (3.6-22 for strata one to five respectively. This study provides new evidence that As in drinking water can cause internal cancers and gives an estimate of the form of this relationship.

  6. Searching for full power control rod patterns in a boiling water reactor using genetic algorithms

    Energy Technology Data Exchange (ETDEWEB)

    Montes, Jose Luis [Departamento Sistemas Nucleares, ININ, Carr. Mexico-Toluca Km. 36.5, Ocoyoacac, Edo. de Mexico (Mexico)]. E-mail: jlmt@nuclear.inin.mx; Ortiz, Juan Jose [Departamento Sistemas Nucleares, ININ, Carr. Mexico-Toluca Km. 36.5, Ocoyoacac, Edo. de Mexico (Mexico)]. E-mail: jjortiz@nuclear.inin.mx; Requena, Ignacio [Departamento Ciencias Computacion e I.A. ETSII, Informatica, Universidad de Granada, C. Daniel Saucedo Aranda s/n. 18071 Granada (Spain)]. E-mail: requena@decsai.ugr.es; Perusquia, Raul [Departamento Sistemas Nucleares, ININ, Carr. Mexico-Toluca Km. 36.5, Ocoyoacac, Edo. de Mexico (Mexico)]. E-mail: rpc@nuclear.inin.mx

    2004-11-01

    One of the most important questions related to both safety and economic aspects in a nuclear power reactor operation, is without any doubt its reactivity control. During normal operation of a boiling water reactor, the reactivity control of its core is strongly determined by control rods patterns efficiency. In this paper, GACRP system is proposed based on the concepts of genetic algorithms for full power control rod patterns search. This system was carried out using LVNPP transition cycle characteristics, being applied too to an equilibrium cycle. Several operation scenarios, including core water flow variation throughout the cycle and different target axial power distributions, are considered. Genetic algorithm fitness function includes reactor security parameters, such as MLHGR, MCPR, reactor k{sub eff} and axial power density.

  7. Effects of source- versus household contamination of tubewell water on child diarrhea in rural Bangladesh: a randomized controlled trial

    National Research Council Canada - National Science Library

    Ercumen, Ayse; Naser, Abu Mohd; Unicomb, Leanne; Arnold, Benjamin F; Colford, Jr, John M; Luby, Stephen P

    2015-01-01

    .... We conducted a randomized controlled trial to assess whether improving the microbiological quality of tubewell drinking water by household water treatment and safe storage would reduce diarrhea in children...

  8. Development of an Accurate Feed-Forward Temperature Control Tankless Water Heater

    Energy Technology Data Exchange (ETDEWEB)

    David Yuill

    2008-06-30

    The following document is the final report for DE-FC26-05NT42327: Development of an Accurate Feed-Forward Temperature Control Tankless Water Heater. This work was carried out under a cooperative agreement from the Department of Energy's National Energy Technology Laboratory, with additional funding from Keltech, Inc. The objective of the project was to improve the temperature control performance of an electric tankless water heater (TWH). The reason for doing this is to minimize or eliminate one of the barriers to wider adoption of the TWH. TWH use less energy than typical (storage) water heaters because of the elimination of standby losses, so wider adoption will lead to reduced energy consumption. The project was carried out by Building Solutions, Inc. (BSI), a small business based in Omaha, Nebraska. BSI partnered with Keltech, Inc., a manufacturer of electric tankless water heaters based in Delton, Michigan. Additional work was carried out by the University of Nebraska and Mike Coward. A background study revealed several advantages and disadvantages to TWH. Besides using less energy than storage heaters, TWH provide an endless supply of hot water, have a longer life, use less floor space, can be used at point-of-use, and are suitable as boosters to enable alternative water heating technologies, such as solar or heat-pump water heaters. Their disadvantages are their higher cost, large instantaneous power requirement, and poor temperature control. A test method was developed to quantify performance under a representative range of disturbances to flow rate and inlet temperature. A device capable of conducting this test was designed and built. Some heaters currently on the market were tested, and were found to perform quite poorly. A new controller was designed using model predictive control (MPC). This control method required an accurate dynamic model to be created and required significant tuning to the controller before good control was achieved. The MPC

  9. Water Level Loggers as a Low-Cost Tool for Monitoring of Stormwater Control Measures

    OpenAIRE

    Laura Toran

    2016-01-01

    Stormwater control measures (SCMs) are a key component of watershed health in urbanized areas. SCMs are used to increase infiltration and reduce discharge to streams or storm sewer systems during rain events. Monitoring is important for the evaluation of design and causes of failure in SCMs. However, the expense of monitoring means it is not always included in stormwater control planning. This study shows how low-cost water level loggers can be used to answer certain questions about SCM perfo...

  10. Wave Synchronizing Crane Control during Water Entry in Offshore Moonpool Operations - Experimental Results

    OpenAIRE

    2004-01-01

    A new strategy for active control in heavy-lift offshore crane operations is suggested, by introducing a new concept referred to as wave synchronization. Wave synchronization reduces the hydrodynamic forces by minimization of variations in the relative vertical velocity between payload and water using a wave amplitude measurement. Wave synchronization is combined with conventional active heave compensation to obtain accurate control. Experimental results using a scale model of a semi-submerge...

  11. Experimental and Numerical Studies of Controlling Thermal Cracks in Mass Concrete Foundation by Circulating Water

    OpenAIRE

    Wenchao Liu; Wanlin Cao; Huiqing Yan; Tianxiang Ye; Wang Jia

    2016-01-01

    This paper summarizes an engineering experience of solving the problem of thermal cracking in mass concrete by using a large project, Zhongguancun No.1 (Beijing, China), as an example. A new method is presented for controlling temperature cracks in the mass concrete of a foundation. The method involves controlled cycles of water circulating between the surface of mass concrete foundation and the atmospheric environment. The temperature gradient between the surface and the core of the mass con...

  12. Carbon dioxide and the stomatal control of water balance and photosynthesis in higher plants

    Energy Technology Data Exchange (ETDEWEB)

    Taiz, L.; Zeiger, E.; Mawson, B. T.; Cornish, K.; Radin, J. W.; Turcotte, E. L.; Hercovitz, S.; Tallman, G.; Karlsson, P. E.; Bogomolni, R. A.; Talbott, L. D.; Srivastava, A.

    1992-01-01

    Research continued into the investigation of the effects of carbon dioxide on stomatal control of water balance and photosynthesis in higher plants. Topics discussed this period include a method of isolating a sufficient number of guard cell chloroplasts for biochemical studies by mechanical isolation of epidermal peels; the measurement of stomatal apertures with a digital image analysis system; development of a high performance liquid chromatography method for quantification of metabolites in guard cells; and genetic control of stomatal movements in Pima cotton. (CBS)

  13. Water management in cities of the future using emission control strategies for priority hazardous substances.

    Science.gov (United States)

    Eriksson, E; Revitt, D M; Ledin, A; Lundy, L; Holten Lützhøft, H C; Wickman, T; Mikkelsen, P S

    2011-01-01

    Cities of the future face challenges with respect to the quantity and quality of water resources, and multiple managerial options need to be considered in order to safeguard urban surface water quality. In a recently completed project on 'Source control options for reducing emissions of Priority Pollutants' (ScorePP), seven emission control strategies (ECSs) were developed and tested within a semi-hypothetical case city (SHCC) to evaluate their potential to reduce the emission of selected European priority hazardous substances (PHSs) to surface waters. The ECSs included (1) business-as-usual, (2) full implementation of relevant European (EU) directives, (3) ECS2 in combination with voluntary options for household, municipalities and industry, (4) ECS2 combined with industrial treatment and best available technologies (BAT), (5) ECS2 in combination with stormwater and combined sewer overflow treatment, (6) ECS2 in combination with advanced wastewater treatment, and (7) combinations of ECS3-6. The SHCC approach was chosen to facilitate transparency, to allow compensating for data gaps and to decrease the level of uncertainty in the results. The selected PHSs: cadmium (Cd), hexachlorobenzene (HCB), nonylphenol (NP) and pentabromodiphenyl ether (PBDE) differ in their uses and environmental fate and therefore accumulate in surface waters to differing extents in response to the application of alternative ECS. To achieve the required reduction in PHS levels in urban waters the full implementation of existing EU regulation is prioritised and feasible combinations of managerial and technological options (source control and treatment) can be highly relevant for mitigating releases.

  14. Microprocessor controlled anodic stripping voltameter for trace metals analysis in tap water

    Energy Technology Data Exchange (ETDEWEB)

    Clem, R.G.; Park, F.W.; Kirsten, F.A.; Phillips, S.L.; Binnall, E.P.

    1981-04-01

    The construction and use of a portable, microprocessor controlled anodic stripping voltameter for on-site simultaneous metal analysis of copper, lead and cadmium in tap water is discussed. The instrumental system is comprised of a programmable controller which permits keying in analytical parameters such as sparge time and plating time; a rotating cell for efficient oxygen removal and amalgam formation; and, a magnetic tape which can be used for data storage. Analysis time can be as short as 10 to 15 minutes. The stripping analysis is based on a pre-measurement step during which the metals from a water sample are concentrated into a thin mercury film by deposition from an acetate solution of pH 4.5. The concentrated metals are then electrochemically dissolved from the film by application of a linearly increasing anodic potential. Typical peak-shaped curves are obtained. The heights of these curves are related to the concentration of metals in the water by calibration data. Results of tap water analysis showed 3 +- 1 ..mu..g/L lead, 22 +- 0.3 ..mu..g/L copper, and less than 0.2 ..mu..g/L cadmium for a Berkeley, California tap water, and 1 to 1000 ..mu..g/L Cu, 1 to 2 ..mu..g/L Pb for ten samples of Seattle, Washington tap water. Recommendations are given for a next generation instrument system.

  15. Questa baseline and pre-mining ground-water-quality investigation. 16. Quality assurance and quality control for water analyses

    Science.gov (United States)

    McCleskey, R. Blaine; Nordstrom, D. Kirk; Naus, Cheryl A.

    2004-01-01

    The Questa baseline and pre-mining ground-water quality investigation has the main objective of inferring the ground-water chemistry at an active mine site. Hence, existing ground-water chemistry and its quality assurance and quality control is of crucial importance to this study and a substantial effort was spent on this activity. Analyses of seventy-two blanks demonstrated that contamination from processing, handling, and analyses were minimal. Blanks collected using water deionized with anion and cation exchange resins contained elevated concentrations of boron (0.17 milligrams per liter (mg/L)) and silica (3.90 mg/L), whereas double-distilled water did not. Boron and silica were not completely retained by the resins because they can exist as uncharged species in water. Chloride was detected in ten blanks, the highest being 3.9 mg/L, probably as the result of washing bottles, filter apparatuses, and tubing with hydrochloric acid. Sulfate was detected in seven blanks; the highest value was 3.0 mg/L, most likely because of carryover from the high sulfate waters sampled. With only a few exceptions, the remaining blank analyses were near or below method detection limits. Analyses of standard reference water samples by cold-vapor atomic fluorescence spectrometry, ion chromatography, inductively coupled plasma-optical emission spectrometry, inductively coupled plasma-mass spectrometry, FerroZine, graphite furnace atomic absorption spectrometry, hydride generation atomic spectrometry, and titration provided an accuracy check. For constituents greater than 10 times the detection limit, 95 percent of the samples had a percent error of less than 8.5. For constituents within 10 percent of the detection limit, the percent error often increased as a result of measurement imprecision. Charge imbalance was calculated using WATEQ4F and 251 out of 257 samples had a charge imbalance less than 11.8 percent. The charge imbalance for all samples ranged from -16 to 16 percent. Spike

  16. Drinking water from alternative water sources: differences in beliefs, social norms and factors of perceived behavioural control across eight Australian locations.

    Science.gov (United States)

    Dolnicar, S; Hurlimann, A

    2009-01-01

    Australia is facing serious challenges in the management of water in various urban and regional locations. Two popular responses to these challenges are increasing supply through alternative water sources such as recycled and desalinated water. However, significant gaps exist in our knowledge of community attitudes to these alternative sources of water, particularly for potable use. This paper reports results from an Australian study of community attitudes to alternative water sources. Sixty six qualitative interviews were held at eight locations with distinctly different water situations. This paper explores all three antecedents to the behaviour of drinking recycled water and desalinated water as postulated by the Theory of Planned Behaviour: attitudes, social norms and factors of perceived behavioural control. Key results indicate that while people hold both positive and negative beliefs (mostly cost, health and environmental concerns) about water from alternative sources, nearly all of them are willing to drink it if the water crisis were to deteriorate further. People also feel they lack knowledge and state that information from scientists would influence their decision to drink recycled and desalinated water most. Friends and relatives are most influential in preventing people from drinking recycled water. The findings reported in this paper have major implications for water policy, and will be of particular interest to water engineers. The paper raises a provocative question: Is it better to avoid public consultation in introducing water from alternative sources?

  17. Control of bacterial contamination in microfiltered water dispensers (MWDs) by disinfection.

    Science.gov (United States)

    Zanetti, Franca; De Luca, Giovanna; Sacchetti, Rossella

    2009-01-15

    Three microfiltered water dispensers (MWDs) for domestic use were bacteriologically monitored over a period of 1 year to evaluate their hygienic status and to compare the ability of two disinfectants (peracetic acid and hydrogen peroxide) to ensure adequate bacteriological quality of the dispensed water. To this end, two dispensers were purposely contaminated with a strain of Pseudomonas aeruginosa of environmental origin. A total of 324 samples of input and output water were analyzed. Heterotrophic plate count (HPC) bacteria at 22 degrees C and 36 degrees C, total coliforms (CT), Escherichia coli (EC), enterococci (ENT), P. aeruginosa and Staphylococcus aureus were enumerated. Throughout the study period, the supply water was always of excellent bacteriological quality. All water samples taken from the MWDs complied with the legal requirements for drinking water: CT, EC, ENT and S. aureus were all consistently absent. P. aeruginosa was never isolated from the uncontaminated dispenser. However, an increase in HPCs up to levels of 10(3)-10(4) cfu/mL was found in the dispensed water. Under the present operative conditions, hydrogen peroxide was seen to be more effective than peracetic acid in controlling bacterial contamination in the water circuits. Periodic disinfection with hydrogen peroxide made it possible to obtain water with HPC levels conforming to Italian regulations for drinking water (disinfection led to a reduction in the concentrations of P. aeruginosa to only a few colony forming units/100 mL or to a complete, albeit temporary, disappearance of the microorganism. In conclusion, hydrogen peroxide at 3% can be proposed as a suitable product for periodic disinfection of domestic MWDs, taking into consideration also its low cost and easy availability.

  18. Hydrogeochemical processes controlling water and dissolved gas chemistry at the Accesa sinkhole (southern Tuscany, central Italy

    Directory of Open Access Journals (Sweden)

    Franco Tassi

    2014-05-01

    Full Text Available The 38.5 m deep Lake Accesa is a sinkhole located in southern Tuscany (Italy that shows a peculiar water composition, being characterized by relatively high total dissolved solids (TDS values (2 g L-1 and a Ca(Mg-SO4 geochemical facies. The presence of significant amounts of extra-atmospheric gases (CO2 and CH4, which increase their concentrations with depth, is also recognized. These chemical features, mimicking those commonly shown by volcanic lakes fed by hydrothermal-magmatic reservoirs, are consistent with those of mineral springs emerging in the study area whose chemistry is produced by the interaction of meteoric-derived waters with Mesozoic carbonates and Triassic evaporites. Although the lake has a pronounced thermocline, water chemistry does not show significant changes along the vertical profile. Lake water balance calculations demonstrate that Lake Accesa has >90% of its water supply from sublacustrine springs whose subterranean pathways are controlled by the local structural assessment that likely determined the sinking event, the resulting funnel-shape being then filled by the Accesa waters. Such a huge water inflow from the lake bottom (~9·106 m3 yr-1 feeds the lake effluent (Bruna River and promotes the formation of water currents, which are able to prevent the establishment of a vertical density gradient. Consequently, a continuous mixing along the whole vertical water column is established. Changes of the drainage system by the deep-originated waters in the nearby former mining district have strongly affected the outflow rates of the local mineral springs; thus, future intervention associated with the ongoing remediation activities should carefully be evaluated to preserve the peculiar chemical features of Lake Accesa.

  19. Multifactorial control of water and saline intake: role of a2-adrenoceptors

    Directory of Open Access Journals (Sweden)

    L.A. De-Luca Jr.

    1997-04-01

    Full Text Available Water and saline intake is controlled by several mechanisms activated during dehydration. Some mechanisms, such as the production of angiotensin II and unloading of cardiovascular receptors, activate both behaviors, while others, such as the increase in blood osmolality or sodium concentration, activate water, but inhibit saline intake. Aldosterone probably activates only saline intake. Clonidine, an a2-adrenergic agonist, inhibits water and saline intake induced by these mechanisms. One model to describe the interactions between these multiple mechanisms is a wire-block diagram, where the brain circuit that controls each intake is represented by a summing point of its respective inhibiting and activating factors. The a2-adrenoceptors constitute an inhibitory factor common to both summing points

  20. Control policies for a water-treatment system using the Markov Decision Process.

    Science.gov (United States)

    Chiam, Tze; Mitchell, Cary; Yih, Yuehwern

    In order to build a decision-making tool for choosing a control policy from a set of predefined policies for a water-treatment system, a simulation was developed. This technology-independent simulation focuses on the functions of a simplified representation of the water system based on documentation by NASA in the Baseline Value and Assumption Documents (BVAD). The clean-water requirement (consumption) and dirty-water generation (production) are based on crewmember demographics, activity schedules, and intensity of each activity. The water system consists of hygiene and potable-water subsystems. The hygiene-water subsystem supplies water for purposes such as laundry, urinal flush, dish wash, oral hygiene, and shower. The potable-water subsystem supplies water for drinking and re-hydration of food. Due to a lack of stochastic property descriptions for a real-world system in the BVAD, stochastic variables are introduced in this research to reflect a more realistic system. These variables describe the magnitude of deviation of system variables from their theoretical values through predetermined statistical distributions. These variables include hygiene and potable-water-treatment efficiencies, amounts of hygiene and potable water consumed, and amount of dirty water produced following potable-water consumption. Conditions of the system occurring hourly result from the intricate interaction of crewmembers and the water system. The primary measure of the condition of the system is the "state" representation of the system, assessed at the beginning of every hour. Conditions of the system examined include the amount of clean water available for consumption, amount of overflow (in excess of storage capacity) of clean and dirty water, amount of hourly water deficiency, amount of accumulated water deficiency, etc. State transitions of the system based on these assessments are affected by the stochastic properties of the system described above. The transitions also depend on

  1. National Conference on Mining-Influenced Waters: Approaches for Characterization, Source Control and Treatment

    Science.gov (United States)

    The conference goal was to provide a forum for the exchange of scientific information on current and emerging approaches to assessing characterization, monitoring, source control, treatment and/or remediation on mining-influenced waters. The conference was aimed at mining remedi...

  2. An Inductive Water Thermostat Using On‐Off Triac Control and Platinum Sensing

    DEFF Research Database (Denmark)

    Diamond, Joseph M.

    1971-01-01

    An on‐off thermostat is described using novel means for heating, sensing, and triac control. Heating is performed by sending the water through a coil of silver tubing which forms the short‐circuited secondary winding of a transformer. This arrangement permits extremely good insulation, which was ...

  3. Vortex breakdown and control experiments in the Ames-Dryden water tunnel

    Science.gov (United States)

    Owen, F. K.; Peake, D. J.

    1987-01-01

    Flow-field measurements have been made to determine the effects of core blowing on vortex breakdown and control. The results of these proof-of-concept experiments clearly demonstrate the usefulness of water tunnels as test platforms for advanced flow-field simulation and measurement.

  4. INVERSE PROBLEM METHOD FOR WATER ENVIRONMENT TOTAL CAPACITY CONTROL OF A TIDAL RIVER

    Institute of Scientific and Technical Information of China (English)

    WANG Dao-zeng; ZHAO Yu-feng; LIN Wei-qing

    2005-01-01

    In this paper, an improved method for water environment total capacity control of tidal rivers was presented. The maximal capacity of point pollution sources for the Huangpu River was computed by this method, and the result was compared with the practically observed data. The numerical result shows that the method is effective and efficient.

  5. Controlling tulip stem nematodes in tulip bulbs by a hot water treatment

    NARCIS (Netherlands)

    Dam, van M.F.N.

    2013-01-01

    A hot water treatment (HWT) protocol is needed to control tulip stem nematode (TSN) in tulip bulbs. A HWT above approximately 45°C in tulips is assumed to be harmful to the bulbs. Experience with HWT to destroy stem nematodes in daffodils shows that the required temperature for this is 4 hours at

  6. Processes controlling the production of aromatic water-soluble organic matter during litter decomposition

    NARCIS (Netherlands)

    Klotzbücher, T.; Kaiser, K.; Filley, T.R.; Kalbitz, K.

    2013-01-01

    Dissolved organic matter (DOM) plays a fundamental role for many soil processes. For instance, production, transport, and retention of DOM control properties and long-term storage of organic matter in mineral soils. Production of water-soluble compounds during the decomposition of plant litter is a

  7. Formal Law and Local Water Control in the Andean Region: A Fiercely Contested Field

    NARCIS (Netherlands)

    Vos, de H.; Boelens, R.A.; Bustamente, R.R.

    2006-01-01

    Water access and control rights of peasant and indigenous communities in Andean countries are threatened. Vertical state law and intervention practices, as well as new privatization policies generally ignore, discriminate or undermine local normative frameworks. Recognition of diverse local rights a

  8. Optimizaton of corrosion control for lead in drinking water using computational modeling techniques

    Science.gov (United States)

    Computational modeling techniques have been used to very good effect in the UK in the optimization of corrosion control for lead in drinking water. A “proof-of-concept” project with three US/CA case studies sought to demonstrate that such techniques could work equally well in the...

  9. Drinking Water Corrosion Control and POU/POE: Where Are the Boundaries?

    Science.gov (United States)

    Protection of public health often has to go beyond regulatory limits, because the health threats do not necessarily arise under the "legal control" of the public water system. Residential and building plumbing can be a very significant contamination source under typical usage co...

  10. Controlling tulip stem nematodes in tulip bulbs by a hot water treatment

    NARCIS (Netherlands)

    Dam, van M.F.N.

    2013-01-01

    A hot water treatment (HWT) protocol is needed to control tulip stem nematode (TSN) in tulip bulbs. A HWT above approximately 45°C in tulips is assumed to be harmful to the bulbs. Experience with HWT to destroy stem nematodes in daffodils shows that the required temperature for this is 4 hours at 47

  11. Measuring the Change in Water Table with Gravity Methods - a Controlled Experiment

    DEFF Research Database (Denmark)

    Lund, S; Christiansen, Lars; Andersen, O. B.;

    2009-01-01

    Gravity changes linearly with the change in soil water content. With the GRACE satellite mission the interest for ground-based gravity methods in hydrology has gained new attention. Time-lapse gravity data have the potential to constrain hydrological model parameters in a calibration scheme...... in water content, a controlled experiment was set up in 30 m by 20 m basin. The water table was lowered 0.69 m within 1½ hours and the corresponding gravity signal measured using two different approaches: a time series measurements at one location and a gravity network measurement including four points....... Both where in agreement with the calculated maximum theoretical gravity change of 27*10^-8 m/s^2. Uncertainties on the change in gravity in the network measurements where 4*10^-8 m/s^2 (one standard deviation). This corresponds to an infinite horizontal slab of water with a thickness of 0.1 m. The time...

  12. Biofilm formation and control in a simulated spacecraft water system - Two-year results

    Science.gov (United States)

    Schultz, John R.; Taylor, Robert D.; Flanagan, David T.; Carr, Sandra E.; Bruce, Rebekah J.; Svoboda, Judy V.; Huls, M. H.; Sauer, Richard L.; Pierson, Duane L.

    1991-01-01

    The ability of iodine to maintain microbial water quality in a simulated spacecraft water system is being studied. An iodine level of about 2.0 mg/L is maintained by passing ultrapure influent water through an iodinated ion exchange resin. Six liters are withdrawn daily and the chemical and microbial quality of the water is monitored regularly. Stainless steel coupons used to monitor biofilm formation are being analyzed by culture methods, epifluorescence microscopy, and scanning electron microscopy. Results from the first two years of operation show a single episode of high bacterial colony counts in the iodinated system. This growth was apparently controlled by replacing the iodinated ion exchange resin. Scanning electron microscopy indicates that the iodine has limited but not completely eliminated the formation of biofilm during the first two years of operation. Significant microbial contamination has been present continuously in a parallel noniodinated system since the third week of operation.

  13. Environmental controls over carbon dioxide and water vapor exchange of terrestrial vegetation

    DEFF Research Database (Denmark)

    Law, B.E.; Falge, E.; Gu, L.;

    2002-01-01

    . FLUXNETs goals are to understand the mechanisms controlling the exchanges of CO2, water vapor and energy across a spectrum of time and space scales, and to provide information for modeling of carbon and water cycling across regions and the globe. At a subset of sites, net carbon uptake (net ecosystem......The objective of this research was to compare seasonal and annual estimates of CO2 and water vapor exchange across sites in forests, grasslands, crops, and tundra that are part of an international network called FLUXNET, and to investigating the responses of vegetation to environmental variables...... associated with reduced temperature. The slope of the relation between monthly gross ecosystem production and evapotranspiration was similar between biomes. except for tundra vegetation, showing a strong linkage between carbon gain and water loss integrated over the year (slopes = 3.4 g CO2/kg H2O...

  14. Breast cancer risk and drinking water contaminated by wastewater: a case control study

    Directory of Open Access Journals (Sweden)

    Swartz Christopher H

    2006-10-01

    Full Text Available Abstract Background Drinking water contaminated by wastewater is a potential source of exposure to mammary carcinogens and endocrine disrupting compounds from commercial products and excreted natural and pharmaceutical hormones. These contaminants are hypothesized to increase breast cancer risk. Cape Cod, Massachusetts, has a history of wastewater contamination in many, but not all, of its public water supplies; and the region has a history of higher breast cancer incidence that is unexplained by the population's age, in-migration, mammography use, or established breast cancer risk factors. We conducted a case-control study to investigate whether exposure to drinking water contaminated by wastewater increases the risk of breast cancer. Methods Participants were 824 Cape Cod women diagnosed with breast cancer in 1988–1995 and 745 controls who lived in homes served by public drinking water supplies and never lived in a home served by a Cape Cod private well. We assessed each woman's exposure yearly since 1972 at each of her Cape Cod addresses, using nitrate nitrogen (nitrate-N levels measured in public wells and pumping volumes for the wells. Nitrate-N is an established wastewater indicator in the region. As an alternative drinking water quality indicator, we calculated the fraction of recharge zones in residential, commercial, and pesticide land use areas. Results After controlling for established breast cancer risk factors, mammography, and length of residence on Cape Cod, results showed no consistent association between breast cancer and average annual nitrate-N (OR = 1.8; 95% CI 0.6 – 5.0 for ≥ 1.2 vs. Conclusion Results did not provide evidence of an association between breast cancer and drinking water contaminated by wastewater. The computer mapping methods used in this study to link routine measurements required by the Safe Drinking Water Act with interview data can enhance individual-level epidemiologic studies of multiple health

  15. Water radiological sanitary control of Veracruz State; Control sanitario radiologico de agua del Estado de Veracruz

    Energy Technology Data Exchange (ETDEWEB)

    Carreon G, E.; Vazquez C, J. A.; Aguilar P, M. del C.; Parissi C, A., E-mail: eulaliacarreon@gmail.com [Laboratorio Estatal de Salud Publica, Eucalipto Mza. 12, Lote 7, Corredor Industrial Bruno Pagliai, 91697 Veracruz (Mexico)

    2014-10-15

    This work is carried out in Veracruz State covering over 11 jurisdictions of the State (Panuco, Tuxpan, Poza Rica, Martinez de la Torre, Xalapa, Cordoba, Orizaba, Veracruz, Cosamaloapan, San Andres Tuxtla and Coatzacoalcos). The sampling was realized in a period from 2009 to 2013 analyzing home drinking water, supply sources and wells, the sampling was done by the sanitary checkers of different jurisdictions with approved methods and the methodology was validated at the State Laboratory of Public Health. 1637 samples were analyzed by counting equipment Tennelec Canberra series 5 and a gas supply system P-10 with calibration curves for alpha and gross beta. The results of measurements ranging from 0.07 to 0.25 Bq/L in the activity concentration gross alpha annual average, an gross beta were from 0.12 to 0.17 Bq/L in the activity concentration gross beta annual average, and with a concentration range of alpha activity up to 0.62 and a minimum 0.02, and the concentration of beta activity of a maximum value 1.54 and a minimum 0.02, taking also as resulted in five years of analysis only 1.16% of the analyzed samples (19 samples) showed a value of alpha activity concentration above the minimum detectable concentration and 62.43% (1022 samples) of the analyzed samples showed a value of beta activity concentration above the minimum detectable concentration, is also clear that the results of the sanitary jurisdictions of Panuco and Tuxpan not have corresponding activity values for the years 2009, 2011-2013 except 2010. We can conclude that the regular measurements of alpha and gross beta activity in water are invaluable for timely detection of radioactive contamination. (Author)

  16. Toward high permeability, selectivity and controllability of water desalination with FePc nanopores.

    Science.gov (United States)

    Deng, Qingming; Pan, Jun; Yin, Xiaohui; Wang, Xiaofeng; Zhao, Lina; Kang, Seung-gu; Jimenez-Cruz, Camilo A; Zhou, Ruhong; Li, Jingyuan

    2016-03-21

    Nanoporous materials exhibit promising potential in water transportation applications, especially in ocean water desalination. It is highly desired to have great permeability, selectivity and controllability in the desalination performance of these nanopores. However, it is still a challenge to achieve all three features in one material or device. Here, we demonstrate efficient and controllable water desalination with a nanoporous 2D Fe phthalocyanine (FePc) membrane using molecular dynamics simulations. We find the FePc membrane not only conducts fast water flow, but it also suppresses ion permeation. The selectivity is attributed to a mechanism distinct from the traditional steric exclusion: cations are excluded due to electrostatic repulsion, whereas anions can be trapped in the nanopore and induce the reorganization of ions in the vicinity of the nanopore, which in turn creates a tendency for the trapped anions to move back into the saline reservoir. More interestingly, we find such mechanism is largely due to the sufficiently strong electrostatic interaction of the charged nanopore region with ions and is not restricted to the FePc nanopore. In addition, the number of protonated nitrogen atoms in FePc pores can be modulated by adjusting the pH value of the solution. The extent of the anion occupancy can thus be regulated, giving rise to control of the water flow. Taken together, great permeability, selectivity and controllability can be achieved with this nanosheet system. Moreover, our study suggests there is an alternative mechanism of water desalination which may be realized by intrinsically nanoporous materials such as FePc membranes.

  17. Research on Controlled Volume Operation Method of Large-scale Water Transfer Canal

    Institute of Scientific and Technical Information of China (English)

    DING Zhiliang; WANG Changde; XU Duo; XIAO Hua

    2011-01-01

    The controlled volume method of operation is especially suitable for large-scale water delivery canal system with complex operation requirements. An operating simulation model based on the storage volume control method for multi-reach canal system in series was established. In allusion to the deficiency of existing controlled volume algorithm, the improved controlled volume algorithm of the whole canal pools was proposed, and the simulation results indicated that the storage volume and water level of each canal pool could be accurately controlled after the improved algorithm had been adopted. However, for some typical discharge demand operating conditions, if the previously mentioned algorithm was adopted, then it certainly would cause some unnecessary gate adjustments, and consequently the disturbed canal pools would be increased. Therefore, the idea of controlled volume operation method of continuous canal pools was proposed, and corresponding algorithm was designed. Through simulating practical project, the results indicated that the new controlled volume algorithm proposed for typical operating conditions could comparatively and obviously reduce the number of regulated check gates and disturb canal pools for some typical discharge demand operating conditions, thus the control efficiency of canal system could be improved.

  18. Synthesis of US Public Water Supply: Spatio-temporal Patterns and Socio-Economic Controls

    Science.gov (United States)

    Arumugam, S.; Sabo, J. L.; Larson, K.; Sinha, T.; Seo, S. B.; Das Bhowmik, R.; Ruhi, A.

    2016-12-01

    Recent USGS water use report suggest that continuously water-use efficiency could mitigate the supply-and-demand imbalance arising from changing climate and growing population. However, this rich data have not been analyzed to understand the underlying spatio-temporal patterns in public supply water use, nor have been investigated to identify the factors contributing to this increased water-use efficiency. A national-scale synthesis of public supply withdrawals ("withdrawals") reveals a strong North-South gradient in public supply water use with the increased population in the US Sunbelt contributing to the increased withdrawal over the South. In contrast, a reverse South-North gradient exists in and per-capita withdrawals ("efficiency"), with northern states consistently improving the efficiency, while the southern states' efficiency declined. Analysis on the role of socio-economic indicators reveals that efficiency has improved in urban counties relative to rural ones, and in counties with higher income and education. We argue that there is a critical need for monthly-to-annual updating of the USGS water-use data for identifying effective strategies that control the water-use efficiency in various geographic settings under a changing climate.

  19. Analysis and control on anomaly water inrush in roof of fully-mechanized mining field

    Institute of Scientific and Technical Information of China (English)

    Peng Linjun; Yang Xiaojie; Sun Xiaoming

    2011-01-01

    Caving of mine roofs from water inrush due to anomalous pressure is one of the major disasters and accidents that can occur in mines during production. Roof water inrush can trigger a wide range of roof collapse, causing major accidents from breaking roof supports while caving. These failures flood wells and do a great deal of damage to mines and endanger mine safety. Our objective is to analyze the anomalies of water inrush crushing the support at the #6301 working face in the ]isan Coal Mine of the Yanzhou Mining Group. Through information of water inrush to the roof, damage caused by tectonic movements, information on the damage caused by roof collapse and the theory about the distribution of pressure in mine abutments, we advice adjusting the length of the working face and the position of open-off cut relatively to the rich water area. In the case of anomalous roof pressure we should develop a state equation to estimate preventive measures with "transferring rock beam" theory. Simultaneously,we improve the capacity of drainage equipment and ensured adequate water retention at the storehouse.These are all major technologies to ensure the control and prevention against accidents caused by anomalous water inrush in roofs, thus ensuring safety in the production process of a coal mine.

  20. Total control-based unified allocation model for allowable basin water withdrawal and sewage discharge

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    In this paper,a new model with a total amount control target of allowable water withdrawal based on initial water right is built for the implementation of initial water right allocation scheme as well as unified allocation for allowable water withdrawal and sewage discharge.The model couples the water allocation simulation model and the computational model of permissible pol-lution bearing capacity.In view of the model complexity,a new technology which synthesizes system simulation,iterative reservoir turns and intelligent computation is proposed to improve the operability of allocation scheme and computational efficiency.Taking the Beijiang River Basin in the Pearl River Basin as an example,the study explains the model establishment,solution and application,and draws an optimized operation graph of large-scale reservoirs.The study also obtains a long-term operation strategy of river basin water resources system,the allocation schemes of allowable water withdrawal and sewage discharge in a typical year and the flow hydrographs of trans-boundary sections.The validity of the model and the allocation rationality are analyzed as well.

  1. Integrated control of landscape irrigation and rainwater harvesting for urban water management

    Science.gov (United States)

    Lee, J. H.; Dhakal, B.; Noh, S.; Seo, D. J.

    2016-12-01

    Demand for freshwater is increasing rapidly in large and fast-growing urban areas such as the Dallas-Fort Worth Metroplex (DFW). With almost complete reliance on surface water, water supply for DFW is limited by the available storage in the reservoir systems which is now subject to larger variability due to climate change. Landscape irrigation is estimated to account for nearly one-third of all residential water use in the US and as much as 60% in dry climate areas. In landscape irrigation, a large portion of freshwater is commonly lost by sub-optimal practices. If practiced over a large area, one may expect optimized smart irrigation to significantly reduce urban freshwater demand. For increasing on-site water supply, rainwater harvesting (RHW) is particularly attractive in that it conserves potable water while reducing stormwater runoff. Traditional static RWH methods, however, have limited success due to the inefficient water usage. If, on the other hand, lawn irrigation and rainwater harvesting can be optimized as an integrated operation and controlled adaptively to the feedback from the environmental sensors, weather conditions and forecast, one may expect the combined benefits for water conservation and stormwater management to be larger. In this work, we develop a prototype system for integrated control of lawn irrigation and RWH for water conservation and stormwater management, and assess and demonstrate the potential impact and value of the system. For in-situ evaluation, we deploy a wireless sensor network consisting of low-cost off-the-shelf sensors and open-sourced components, and collect observations of temperature, humidity, soil moisture, and solar radiation at the test site at the UTA community garden in Arlington, Texas. We assess the health of the lawn grass using normalized vegetation index (NDVI) from the time lapse images at the site. In this poster, we describe the approach and share the initial results.

  2. Controls of interactions between iron hydroxide colloid and water on REE fractionations in surface waters: Experimen-tal study on pH-controlling mechanism

    Institute of Scientific and Technical Information of China (English)

    刘丛强; 吴佳红; 于文辉

    2002-01-01

    The influence of pH on the partitioning behavior of REE at the water/particulate interface has been studied experimentally. At the beginning of colloid formation the adsorption of REE on iron hydroxide colloids is dominant, followed by REE desorption. Finally adsorption and desorption tend to reach equilibration. The capability of iron hydroxide colloids to adsorb the HREE is greater than that to adsorb the LREE. With increasing pH, LREE/HREE fractionations will take place between iron hydroxide colloids and water, leading to the reduction of their partition coefficient ratio (DLREE/DHREE). The DREE distribution patterns show Y anomalies (DY/DHo <1), with obvious REE tetrad effects appearing under low pH conditions. Experimental results have shown that there do exist REE tetrad effects in nature. In addition to pH, the chemical type of surface water and ion intensity are also the important factors controlling REE tetrad effects and leading to fractionations between particulate-adsorbed REE and dissolved REE.

  3. The effects of co-cultivation of pearl mussels and fishes on water pollution control in middle or small sized water

    Institute of Scientific and Technical Information of China (English)

    ZHANG Genfang; DENG Minzhong; FANG Aiping

    2004-01-01

    Our field experiments showed that the cultivation of pearl mussels formed a new biocoene composed of filamentous algae, protozoa, porifera and coelenterate. It effectively reduced nitrogen, phosphorus, chemical oxygen demand and biochemical oxygen demand in the water by 67.3%, 73.2%, 38.1% and 15.5%, respectively, during May to September 1998 when the water eutrophication was developing. This could control water eutrophication and produce pearls, shellfish meat and shells. This is an economical and effective way to control water eutrophication by using the ultra strong filtering capability of freshwater pearl mussels.

  4. The effects of co-cultivation of pearl mussels and fishes on water pollution control in middle or small sized water

    Science.gov (United States)

    Zhang, Genfang; Deng, Minzhong; Fang, Aiping

    2004-12-01

    Our field experiments showed that the cultivation of pearl mussels formed a new biocoene composed of filamentous algae, protozoa, porifera and coelenterate. It effectively reduced nitrogen, phosphorus, chemical oxygen demand and biochemical oxygen demand in the water by 67.3%, 73.2%, 38.1% and 15.5%, respectively, during May to September 1998 when the water eutrophication was developing. This could control water eutrophication and produce pearls, shellfish meat and shells. This is an economical and effective way to control water eutrophication by using the ultra strong filtering capability of freshwater pearl mussels.

  5. Study of Dynamic Robustness of Servo Control System on a Water Press

    Institute of Scientific and Technical Information of China (English)

    KONG Xiangdong; YAO Jing; GAO Yingjie; ZHANG Qin

    2006-01-01

    The reliability and robustness of the electro-hydraulic servo control system for heavy-duty forging machine play an important role in forging processes. A mathematic model of 50 MN water press for free forging was created in this research. The dynamic robust compensator integrating with PID control method is designed and applied to the mathematical model simulation. The simulated results approved that the dynamic robust compensator application restrains interference from extra load and improves the electro-hydraulic position servo control system accuracy and stability.

  6. Fresh water swimming as a risk factor for otitis externa: a case-control study.

    Science.gov (United States)

    Springer, G L; Shapiro, E D

    1985-01-01

    A case-control study was conducted in which the amount and sites (fresh-water lakes and rivers, chlorinated pools, or the ocean) of recent swimming by 105 patients with otitis externa were compared with that of 239 controls. Swimming during the week prior to the visit was strongly associated with otitis externa. When the 80 cases and 127 controls with a history of recent swimming were compared, otitis externa was positively associated with the amount of swimming during the preceding week. Otitis externa was also positively associated with swimming in fresh water compared with ocean or pool swimming with the magnitude of this association being more pronounced at higher levels of exposure.

  7. Water sources and controls on water-loss rates of epigeous ectomycorrhizal fungal sporocarps during summer drought

    Science.gov (United States)

    Erik A. Lilleskov; Thomas D. Bruns; Todd E. Dawson; Francisco J. Camacho

    2009-01-01

    Access to deeper soil water and water-conserving traits should reduce water stress for ectomycorrhizal fungi, permitting function during drought. Here, we explored whether epigeous fruiting of ectomycorrhizal fungi during drought was facilitated by access to deep soil water, how much water was lost from sporocarps, and how sporocarp surface to volume ratios affected...

  8. Hydrogeologic controls of surface-water chemistry in the Adirondack region of New York State

    Science.gov (United States)

    Peters, N.E.; Driscoll, C.T.

    1987-01-01

    Relationships between surface-water discharge, water chemistry, and watershed geology were investigated to evaluate factors affecting the sensitivity of drainage waters in the Adirondack region of New York to acidification by atmospheric deposition. Instantaneous discharge per unit area was derived from relationships between flow and staff-gage readings at 10 drainage basins throughout the region. The average chemical composition of the waters was assessed from monthly samples collected from July 1982 through July 1984. The ratio of flow at the 50-percent exceedence level to the flow at the 95-percent exceedence level of flow duration was negatively correlated with mean values of alkalinity or acid-neutralizing capacity (ANC), sum of basic cations (SBC), and dissolved silica, for basins containing predominantly aluminosilicate minerals and little or no carbonate-bearing minerals. Low ratios are indicative of systems in which flow is predominately derived from surface- and ground-water storage, whereas high ratios are characteristic of watersheds with variable flow that is largely derived from surface runoff. In an evaluation of two representative surface-water sites, concentrations of ANC, SBC, and dissolved silica, derived primarily from soil mineral weathering reactions. decreased with increasing flow. Furthermore, the ANC was highest at low flow when the percentage of streamflow derived from ground water was maximum. As flow increased, the ANC decreased because the contribution of dilute surface runoff and lateral flow through the shallow acidic soil horizons to total flow increased. Basins having relatively high ground-water contributions to total flow, in general, have large deposits of thick till or stratified drift. A major factor controlling the sensitivity of these streams and lakes to acidification is the relative contribution of ground water to total discharge. ?? 1987 Martinus Nijhoff/Dr W. Junk Publishers.

  9. Biofilm problems in dental unit water systems and its practical control.

    LENUS (Irish Health Repository)

    Coleman, D C

    2009-05-01

    Dental chair units (DCUs) contain integrated systems that provide the instruments and services for a wide range of dental procedures. DCUs use water to cool and irrigate DCU-supplied instruments and tooth surfaces during dental treatment. Water is supplied to these instruments by a network of interconnected narrow-bore (2-3 mm) plastic tubes called dental unit waterlines (DUWLs). Many studies over the last 40 years demonstrated that DUWL output water is often contaminated with high densities of micro-organisms, predominantly Gram-negative aerobic heterotropic environmental bacteria, including Legionella and Pseudomonas species. Untreated DUWLs host biofilms that permit micro-organisms to multiply and disperse through the water network and which are aerosolized by DCU instrument use, thus exposing patients and staff to these micro-organisms, to fragments of biofilm and bacterial endotoxins. This review concentrates on how practical developments and innovations in specific areas can contribute to effective DUWL biofilm control. These include the use of effective DUWL treatment agents, improvements to DCU supply water quality, DCU design changes, development of automated DUWL treatment procedures that are effective at controlling biofilm in the long-term and require minimal human intervention, are safe for patients and staff, and which do not cause deterioration of DCU components following prolonged use.

  10. Legionella Risk Management and Control in Potable Water Systems: Argument for the Abolishment of Routine Testing.

    Science.gov (United States)

    Whiley, Harriet

    2016-12-24

    Legionella is an opportunistic pathogen of public health significance. One of the main sources of Legionella is potable water systems. As a consequence of aging populations there is an increasing demographic considered at high risk for Legionellosis and, as such, a review of the guidelines is required. Worldwide, Legionella has been detected from many potable water sources, suggesting it is ubiquitous in this environment. Previous studies have identified the limitations of the current standard method for Legionella detection and the high possibility of it returning both false negative and false positive results. There is also huge variability in Legionella test results for the same water sample when conducted at different laboratories. However, many guidelines still recommend the testing of water systems. This commentary argues for the removal of routine Legionella monitoring from all water distribution guidelines. This procedure is financially consuming and false negatives may result in managers being over-confident with a system or a control mechanism. Instead, the presence of the pathogen should be assumed and focus spent on managing appropriate control measures and protecting high-risk population groups.

  11. Legionella Risk Management and Control in Potable Water Systems: Argument for the Abolishment of Routine Testing

    Science.gov (United States)

    Whiley, Harriet

    2016-01-01

    Legionella is an opportunistic pathogen of public health significance. One of the main sources of Legionella is potable water systems. As a consequence of aging populations there is an increasing demographic considered at high risk for Legionellosis and, as such, a review of the guidelines is required. Worldwide, Legionella has been detected from many potable water sources, suggesting it is ubiquitous in this environment. Previous studies have identified the limitations of the current standard method for Legionella detection and the high possibility of it returning both false negative and false positive results. There is also huge variability in Legionella test results for the same water sample when conducted at different laboratories. However, many guidelines still recommend the testing of water systems. This commentary argues for the removal of routine Legionella monitoring from all water distribution guidelines. This procedure is financially consuming and false negatives may result in managers being over-confident with a system or a control mechanism. Instead, the presence of the pathogen should be assumed and focus spent on managing appropriate control measures and protecting high-risk population groups. PMID:28029126

  12. The Consumption of Bicarbonate-Rich Mineral Water Improves Glycemic Control

    Directory of Open Access Journals (Sweden)

    Shinnosuke Murakami

    2015-01-01

    Full Text Available Hot spring water and natural mineral water have been therapeutically used to prevent or improve various diseases. Specifically, consumption of bicarbonate-rich mineral water (BMW has been reported to prevent or improve type 2 diabetes (T2D in humans. However, the molecular mechanisms of the beneficial effects behind mineral water consumption remain unclear. To elucidate the molecular level effects of BMW consumption on glycemic control, blood metabolome analysis and fecal microbiome analysis were applied to the BMW consumption test. During the study, 19 healthy volunteers drank 500 mL of commercially available tap water (TW or BMW daily. TW consumption periods and BMW consumption periods lasted for a week each and this cycle was repeated twice. Biochemical tests indicated that serum glycoalbumin levels, one of the indexes of glycemic controls, decreased significantly after BMW consumption. Metabolome analysis of blood samples revealed that 19 metabolites including glycolysis-related metabolites and 3 amino acids were significantly different between TW and BMW consumption periods. Additionally, microbiome analysis demonstrated that composition of lean-inducible bacteria was increased after BMW consumption. Our results suggested that consumption of BMW has the possible potential to prevent and/or improve T2D through the alterations of host metabolism and gut microbiota composition.

  13. System Level Analysis of a Water PCM HX Integrated Into Orion's Thermal Control System Abstract

    Science.gov (United States)

    Navarro, Moses; Hansen, Scott; Ungar, Eugene; Sheth, Rubik

    2015-01-01

    In a cyclical heat load environment such as low Lunar orbit, a spacecraft's radiators are not sized to reject the full heat load requirement. Traditionally, a supplemental heat rejection device (SHReD) such as an evaporator or sublimator is used to act as a "topper" to meet the additional heat rejection demands. Utilizing a Phase Change Material (PCM) heat exchanger (HX) as a SHReD provides an attractive alternative to evaporators and sublimators as PCM HXs do not use a consumable, thereby leading to reduced launch mass and volume requirements. In continued pursuit of water PCM HX development an Orion system level analysis was performed using Thermal Desktop for a water PCM HX integrated into Orion's thermal control system and in a 100km Lunar orbit. The study analyzed 1) placing the PCM on the Internal Thermal Control System (ITCS) versus the External Thermal Control System (ETCS) 2) use of 30/70 PGW verses 50/50 PGW and 3) increasing the radiator area in order to reduce PCM freeze times. The analysis showed that for the assumed operating and boundary conditions utilizing a water PCM HX on Orion is not a viable option. Additionally, it was found that the radiator area would have to be increased over 20% in order to have a viable water-based PCM HX.

  14. System Level Analysis of a Water PCM HX Integrated into Orion's Thermal Control System

    Science.gov (United States)

    Navarro, Moses; Hansen, Scott; Seth, Rubik; Ungar, Eugene

    2015-01-01

    In a cyclical heat load environment such as low Lunar orbit, a spacecraft's radiators are not sized to reject the full heat load requirement. Traditionally, a supplemental heat rejection device (SHReD) such as an evaporator or sublimator is used to act as a "topper" to meet the additional heat rejection demands. Utilizing a Phase Change Material (PCM) heat exchanger (HX) as a SHReD provides an attractive alternative to evaporators and sublimators as PCM HXs do not use a consumable, thereby leading to reduced launch mass and volume requirements. In continued pursuit of water PCM HX development an Orion system level analysis was performed using Thermal Desktop for a water PCM HX integrated into Orion's thermal control system in a 100km Lunar orbit. The study verified of the thermal model by using a wax PCM and analyzed 1) placing the PCM on the Internal Thermal Control System (ITCS) versus the External Thermal Control System (ETCS) 2) use of 30/70 PGW verses 50/50 PGW and 3) increasing the radiator area in order to reduce PCM freeze times. The analysis showed that for the assumed operating and boundary conditions utilizing a water PCM HX on Orion is not a viable option for any case. Additionally, it was found that the radiator area would have to be increased by at least 40% in order to support a viable water-based PCM HX.

  15. Experimental and Numerical Studies of Controlling Thermal Cracks in Mass Concrete Foundation by Circulating Water

    Directory of Open Access Journals (Sweden)

    Wenchao Liu

    2016-04-01

    Full Text Available This paper summarizes an engineering experience of solving the problem of thermal cracking in mass concrete by using a large project, Zhongguancun No.1 (Beijing, China, as an example. A new method is presented for controlling temperature cracks in the mass concrete of a foundation. The method involves controlled cycles of water circulating between the surface of mass concrete foundation and the atmospheric environment. The temperature gradient between the surface and the core of the mass concrete is controlled at a relatively stable state. Water collected from the well-points used for dewatering and from rainfall is used as the source for circulating water. Mass concrete of a foundation slab is experimentally investigated through field temperature monitoring. Numerical analyses are performed by developing a finite element model of the foundation with and without water circulation. The calculation parameters are proposed based on the experiment, and finite element analysis software MIDAS/CIVIL is used to calculate the 3D temperature field of the mass concrete during the entire process of heat of hydration. The numerical results are in good agreement with the measured results. The proposed method provides an alternative practical basis for preventing thermal cracks in mass concrete.

  16. Bioinspired Smart Peristome Surface for Temperature-Controlled Unidirectional Water Spreading.

    Science.gov (United States)

    Zhang, Pengfei; Chen, Huawei; Li, Li; Liu, Hongliang; Liu, Guang; Zhang, Liwen; Zhang, Deyuan; Jiang, Lei

    2017-02-15

    Unidirectional liquid spreading without energy input has attracted considerable attention due to various potential applications such as biofluidics devices and self-lubrication. Introducing a surface wettable gradient or asymmetric nanostructures onto the surface has successfully harnessed the liquid to spread unidirectionally. However, these surfaces are still plagued with problems that restrict their practical applications: fixed spreading state for a fixed surface, and spreading slowly over a short distance. Herein, bioinspired from the fast continuous unidirectional water transport on the peristome of Nepenthes alata, we report a smart peristome with temperature-controlled unidirectional water spreading. The smart artificial peristome was fabricated by grafting the thermoresponsive material PNIPAAm onto the artificial PDMS peristome. Unidirectional water spreading on the smart peristome can be dynamically regulated by changing the surface temperature. Besides, the water spreading is demonstrated with a remarkable reversibility and stability. By investigating the relationship between liquid spreading distance and wettability, the underlying mechanism was revealed. This work gives a new way to achieve the control of unidirectional liquid spreading available for controllable microfluidics and medical devices.

  17. Storm water management in an urban catchment: effects of source control and real-time management of sewer systems on receiving water quality.

    Science.gov (United States)

    Frehmann, T; Nafo, I; Niemann, A; Geiger, W F

    2002-01-01

    For the examination of the effects of different storm water management strategies in an urban catchment area on receiving water quality, an integrated simulation of the sewer system, wastewater treatment plant and receiving water is carried out. In the sewer system real-time control measures are implemented. As examples of source control measures the reduction of wastewater and the reduction of the amount of impervious surfaces producing storm water discharges are examined. The surface runoff calculation and the simulation of the sewer system and the WWTP are based on a MATLAB/SIMULINK simulation environment. The impact of the measures on the receiving water is simulated using AQUASIM. It can be shown that the examined storm water management measures, especially the source control measures, can reduce the combined sewer overflow volume and the pollutant discharge load considerably. All examined measures also have positive effects on the receiving water quality. Moreover, the reduction of impervious surfaces avoids combined sewer overflow activities, and in consequence prevents pollutants from discharging into the receiving water after small rainfall events. However, the receiving water quality improvement may not be seen as important enough to avoid acute receiving water effects in general.

  18. Better well control through safe drilling margin identification, influx analysis and direct bottom hole pressure control method for deep water

    Energy Technology Data Exchange (ETDEWEB)

    Veeningen, Daan [National Oilwell Varco IntelliServ (NOV), Houston, TX (United States)

    2012-07-01

    Currently, well control events are almost exclusively detected by using surface measurements. Measuring a volume increase in the 'closed loop' mud circulation system; a standpipe pressure decrease; or changes in a variety of drilling parameters provide indicators of a kick. Especially in deep water, where the riser comprises a substantial section of the well bore, early kick detection is paramount for limiting the severity of a well bore influx and improve the ability to regain well control. While downhole data is presently available from downhole tools nearby the bit, available data rates are sparse as mud pulse telemetry bandwidth is limited and well bore measurements compete with transmission of other subsurface data. Further, data transfer is one-directional, latency is significant and conditions along the string are unknown. High-bandwidth downhole data transmission system, via a wired or networked drill string system, has the unique capability to acquire real-time pressure and temperature measurement at a number of locations along the drill string. This system provides high-resolution downhole data available at very high speed, eliminating latency and restrictions that typically limit the availability of downhole data. The paper describes well control opportunities for deep water operations through the use of downhole data independent from surface measurements. First, the networked drill string provides efficient ways to identify pore pressure, fracture gradient, and true mud weight that comprise the safe drilling margin. Second, the independent measurement capability provides early kick detection and improved ability to analyze an influx even with a heterogeneous mud column through distributed along-string annular pressure measurements. Third, a methodology is proposed for a direct measurement method using downhole real-time pressure for maintaining constant bottom hole pressure during well kills in deep water. (author)

  19. Determining optimal corrosion control techniques for small water systems: A unique and systematic approach

    Energy Technology Data Exchange (ETDEWEB)

    Tarallo, S.M.; Beardsley, E. [Camp Dresser & McKee Inc., Povidence, RI (United States); Pytel, D.; Chaplin, T. [Rhode Island Department of Health, Providence, RI (United States)

    1996-11-01

    The Lead and Copper Rule represents one of the most complex rules currently in effect for small water treatment systems. In an effort to attain timely compliance by small systems with limited technical and financial resources, the Rhode Island Department of Health (RIDOH) Division of Drinking Water Quality initiated a study to recommend appropriate corrosion control approaches. The study encompassed three goals: to continue a good compliance record, to help small systems reduce their lead and copper levels, and to avoid unnecessary safety risks to operators and customers.

  20. Information Management System for the California State Water Resources Control Board (SWRCB)

    Science.gov (United States)

    Heald, T. C.; Redmann, G. H.

    1973-01-01

    A study was made to establish the requirements for an integrated state-wide information management system for water quality control and water quality rights for the State of California. The data sources and end requirements were analyzed for the data collected and used by the numerous agencies, both State and Federal, as well as the nine Regional Boards under the jurisdiction of the State Board. The report details the data interfaces and outlines the system design. A program plan and statement of work for implementation of the project is included.

  1. Implementing supercritical water oxidation technology in a lunar base environmental control/life support system

    Science.gov (United States)

    Meyer Sedej, M.

    1985-01-01

    A supercritical water oxidation system (SCWOS) offers several advantages for a lunar base environmental control/life support system (ECLSS) compared to an ECLSS based on Space Station technology. In supercritically heated water (630 K, 250 atm) organic materials mix freely with oxygen and undergo complete combustion. Inorganic salts lose solubility and precipitate out. Implementation of SCWOS can make an ECLSS more efficient and reliable by elimination of several subsystems and by reduction in potential losses of life support consumables. More complete closure of the total system reduces resupply requirements from the earth, a crucial cost item in maintaining a lunar base.

  2. Water control wells methodology, applied in Orinoco Belt Morichal district, Venezuela

    Energy Technology Data Exchange (ETDEWEB)

    Marcano, B.; Ramos, M.; Brown, J.; Lagrave, G.; Lista, H.; Ugas, L. [Petroleos de Venezuela SA, Caracas (Venezuela)

    2006-07-01

    The Orinoco Oil Belt is located next to the lower Orinoco River in eastern Venezuela, and contains large deposits of extra heavy oil. Water cut is a significant problem in the area due to aquifer activity and the fact that many wells are drilled in close proximity to the aquifer. This paper provided details of a pilot test conducted in the Carabobo and Morichal oilfield to evaluate a water control technique designed for use with horizontal wells. The method drained water through the horizontal wells that reached a water cut of higher than 80 per cent in order to protect neighbouring wells from potential water breakthrough in cases where the wells were completed close to aquifers. Results of the 2 pilot tests demonstrated that the method reduced water cut in the wells by 45 per cent. Total expected production increases were estimated at 542 bpd for a 4 well cluster. It was concluded that simulation and reservoir characterization studies are needed to optimize the methodology. 2 refs., 2 tabs., 11 figs.

  3. Evaporation of sessile water/ethanol drops in a controlled environment.

    Science.gov (United States)

    Liu, Chuanjun; Bonaccurso, Elmar; Butt, Hans-Jürgen

    2008-12-21

    The evaporation of water/ethanol drops with different mixing ratios was investigated at controlled vapor pressure of water (relative humidity) and ethanol in the background gas. Therefore, a drop of about 1 microL was deposited on a hydrophobized silicon substrate at room temperature in a closed cell. With a microscope camera we monitored the contact angle, the volume and the contact radius of the drops as function of time. Pure water drops evaporated in constant contact angle mode. The evaporation rate of water decreased with increasing humidity. In mixed drops ethanol did not evaporate completely at first, but a fraction still remained in the drop until the end of evaporation. Depending on ethanol concentration in the drop and on relative humidity in the background gas, water vapor condensed at the beginning of the evaporation of mixed drops. Also, at a high vapor pressure of ethanol, ethanol condensed at the beginning of the evaporation. The presence of ethanol vapor accelerated the total evaporation time of water drops.

  4. Bioretention storm water control measures decrease the toxicity of copper roof runoff.

    Science.gov (United States)

    LaBarre, William J; Ownby, David R; Rader, Kevin J; Lev, Steven M; Casey, Ryan E

    2016-11-17

    The present study evaluated the ability of 2 different bioretention storm water control measures (SCMs), planter boxes and swales, to decrease the toxicity of sheet copper (Cu) roofing runoff to Daphnia magna. The present study quantified changes in storm water chemistry as it passed through the bioretention systems and utilized the biotic ligand model (BLM) to assess whether the observed D. magna toxicity could be predicted by variations found in water chemistry. Laboratory toxicity tests were performed using select storm samples with D. magna cultured under low ionic strength conditions that were appropriate for the low ionic strength of the storm water samples being tested. The SCMs decreased toxicity of Cu roof runoff in both the BLM results and the storm water bioassays. Water exiting the SCMs was substantially higher than influent runoff in pH, ions, alkalinity, and dissolved organic carbon and substantially lower in total and dissolved Cu. Daphnids experienced complete mortality in untreated runoff from the Cu roof (the SCM influent); however, for planter and swale effluents, survival averaged 86% and 95%, respectively. The present study demonstrated that conventional bioretention practices, including planter boxes and swales, are capable of decreasing the risk of adverse effects from sheet Cu roof runoff to receiving systems, even before considering dilution of effluents in those receiving systems and associated further reductions in copper bioavailability. Environ Toxicol Chem 2016;9999:1-9. © 2016 SETAC.

  5. Tunable, Strain-Controlled Nanoporous MoS₂ Filter for Water Desalination.

    Science.gov (United States)

    Li, Weifeng; Yang, Yanmei; Weber, Jeffrey K; Zhang, Gang; Zhou, Ruhong

    2016-02-23

    The deteriorating state of global fresh water resources represents one of the most serious challenges that scientists and policymakers currently face. Desalination technologies, which are designed to extract potable water from the planet's bountiful stores of seawater, could serve to alleviate much of the stress that presently plagues fresh water supplies. In recent decades, desalination methods have improved via water-filtering architectures based on nanoporous graphene filters and artificial membranes integrated with biological water channels. Here, we report the auspicious performance (in simulations) of an alternative nanoporous desalination filter constructed from a MoS2 nanosheet. In striking contrast to graphene-based filters, we find that the "open" and "closed" states of the MoS2 filter can be regulated by the introduction of mechanical strain, yielding a highly tunable nanopore interface. By applying lateral strain to the MoS2 filter in our simulations, we see that the transition point between "open" and "closed" states occurs under tension that induces about 6% cross-sectional expansion in the membrane (6% strain); the open state of the MoS2 filter demonstrates high water transparency and a strong salt filtering capability even under 12% strain. Our results thus demonstrate the promise of a controllable nanoporous MoS2 desalination filter, wherein the morphology and size of the central nanopore can be precisely regulated by tensile strain. These findings support the design and proliferation of tunable nanodevices for filtration and other applications.

  6. Study of polymorphic control in an ethanol-water binary solvent

    Science.gov (United States)

    Kitano, Hiroshi; Tanaka, Takayuki; Hirasawa, Izumi

    2017-07-01

    Three polymorphs of L-Citrulline crystals, anhydrate (Form α, γ and δ) and pseudo polymorph (dihydrate), were confirmed. In this study, polymorphic control of L-Citrulline was attempted by changing the ethanol concentration in ethanol-water binary solvents. First, each polymorph of L-Citrulline crystals was added to the prepared ethanol-water binary solvents and samples which were obtained chronologically were measured by XRD. Also, the crystal sizes and shapes in transformation were observed by microscope. Then, polymorphs of the crystals after transformation were determined by XRD pattern. As a result, the transformation from dihydrate to anhydrate was observed by adding dihydrate crystals to the ethanol-water binary solvent. Similarly, the transformation from anhydrate to another anhydrate was observed. Especially in the case of adding dihydrate, the existences of all polymorphs were confirmed by adjusting ethanol-water binary solvent. According to the results, it was revealed that polymorphic transformation was affected by the trace amount of water contained in ethanol-water binary solvent. Moreover, transformation from dihydrate to anhydrate was constructed with three phases, dissolution of dihydrate, nucleation and growth of anhydrate. Therefore, the solution-mediated polymorphic transformation was supposed to be a key mechanism for this transformation.

  7. Application of the control method by visual path to the water injection projects of Petroleos Mexicanos

    Energy Technology Data Exchange (ETDEWEB)

    Pechir, Q.V.M.

    1972-04-01

    In the present work, the importance is pointed out of the physical and economical magnitude of secondary recovery of oil by injection of water. This is for the purpose of emphasizing the urgent necessity of attending to the problems of control and supervision which present themselves during the development of the projects. An example of such a project is cited (Tamaulipas-Constitucion) where the problems and failures gave many opportunities for delay in completion of some of the work. In some instances, there was overspending which might have been avoided in great part, if there had been controls and supervision suitable and adequate in importance to the magnitude and complexity of the project. Because of such situations, and for overcoming the initial deficiencies in control and supervision of these water-injection projects, it was decided to adopt the Visiflex method of control and the Visual Path method of work scheduling. A description of the parts is integrated into the method as well as the techniques of its application n the mentioned project, including a model of the Visual Path Program for the water- injection project in the Caliza San Andres (San Andres Limestone) formations of the Tamaulipas-Constitucion oil field.

  8. Water pollution control technology and strategy for river-lake systems: a case study in Gehu Lake and Taige Canal.

    Science.gov (United States)

    Zhang, Yimin; Zhang, Yongchun; Gao, Yuexiang; Zhang, Houhu; Cao, Jianying; Cai, Jinbang; Kong, Xiangji

    2011-07-01

    The Taoge water system is located in the upstream of Taihu Lake basin and is characterized by its multi-connected rivers and lakes. In this paper, current analyses of hydrology, hydrodynamics and water pollution of Gehu Lake and Taige Canal are presented. Several technologies are proposed for pollution prevention and control, and water environmental protection in the Taihu Lake basin. These included water pollution control integration technology for the water systems of Gehu Lake, Taige Canal and Caoqiao River. Additionally, river-lake water quality and quantity regulation technology, ecological restoration technology for polluted and degraded water bodies, and water environmental integration management and optimization strategies were also examined. The main objectives of these strategies are to: (a) improve environmental quality of relative water bodies, prevent pollutants from entering Gehu Lake and Taige Canal, and ensure that the clean water after the pre-treatment through Gehu Lake is not polluted before entering the Taihu Lake through Taige Canal; (b) stably and efficiently intercept and decrease the pollution load entering the lake through enhancing the river outlet ecological system structure function and water self-purifying capacity, and (c) designate Gehu Lake as a regulation system for water quality and water quantity in the Taoge water system and thus guarantee the improvement of the water quality of the inflow into Taihu Lake.

  9. Measuring the Change in Water Table with Gravity Methods - a Controlled Experiment

    DEFF Research Database (Denmark)

    Lund, S; Christiansen, Lars; Andersen, O. B.

    2009-01-01

    in water content, a controlled experiment was set up in 30 m by 20 m basin. The water table was lowered 0.69 m within 1½ hours and the corresponding gravity signal measured using two different approaches: a time series measurements at one location and a gravity network measurement including four points....... Both where in agreement with the calculated maximum theoretical gravity change of 27*10^-8 m/s^2. Uncertainties on the change in gravity in the network measurements where 4*10^-8 m/s^2 (one standard deviation). This corresponds to an infinite horizontal slab of water with a thickness of 0.1 m. The time...

  10. Coaxial electrospinning for encapsulation and controlled release of fragile water-soluble bioactive agents.

    Science.gov (United States)

    Jiang, Hongliang; Wang, Liqun; Zhu, Kangjie

    2014-11-10

    Coaxial electrospinning is a robust technique for one-step encapsulation of fragile, water-soluble bioactive agents, including growth factors, DNA and even living organisms, into core-shell nanofibers. The coaxial electrospinning process eliminates the damaging effects due to direct contact of the agents with organic solvents or harsh conditions during emulsification. The shell layer serves as a barrier to prevent the premature release of the water-soluble core contents. By varying the structure and composition of the nanofibers, it is possible to precisely modulate the release of the encapsulated agents. Promising work has been done with coaxially electrospun non-woven mats integrated with bioactive agents for use in tissue engineering, in local delivery and in wound healing, etc. This paper reviews the origins of the coaxial electrospinning method, its updated status and potential future developments for controlled release of the class of fragile, water-soluble bioactive agents.

  11. Criminal sanctions applicable to Federal water pollution control measures. Master's thesis

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, J.C.

    1991-09-30

    Overkill or not enough: Two decades ago, Congress realized that a system of civil remedies alone, devoid of any lasting punitive consequences, was inadequate to insure compliance with environmental protection statutes. Other than the Rivers and Harbors Act of 1899, which was designed to protect navigation, Federal criminal sanctions were not applicable to water pollution offenses. The Federal Water Pollution Control Act, more commonly known as the Clean Water Act (CWA), was twenty-four years old before Federal criminal enforcement of its provisions was allowed. But since the early 1970's, the criminal provisions of the CWA have been strengthened, the United States Department of Justice has beefed up its environmental enforcement efforts, and environmental polluters have been prosecuted. This Federal effort is now approaching overkill.

  12. Chlorine dioxide as a disinfectant for Ralstonia solanacearum control in water, storage and equipment

    Directory of Open Access Journals (Sweden)

    Popović Tatjana

    2016-01-01

    Full Text Available Brown rot or bacterial wilt caused by bacterium Ralstonia solanacearum is the main limiting factor in potato production. Quarantine measures are necessary to avoid spread of disease to disease-free areas. R. solanacearum has been shown to contaminate watercourses from which crop irrigation is then prohibited causing further potential losses in yield and quality. The bacteria also spread via surfaces that diseased seed potatoes come into contact with. This study showed bactericidal activity of chlorine dioxide (CIO2 on R. solanacearum for disinfection of water, surface and equipment. The results showed that CIO2 solution at concentration of 2 ppm at 30 minutes of exposure time had bactericidal effect for disinfection of water. For surface and equipment disinfection, concentration of 50 ppm showed total efficacy at 30 min and 5 sec exposure time, respectively. Results suggest that use of CIO2 as a disinfectant has a potential for control of brown rot pathogen in water, storage and equipment.

  13. Biofilm formation and control in a simulated spacecraft water system - Interim results

    Science.gov (United States)

    Schultz, John R.; Taylor, Robert D.; Flanagan, David T.; Gibbons, Randall E.; Brown, Harlan D.; Sauer, Richard L.

    1989-01-01

    The ability of iodine to control microbial contamination and biofilm formation in spacecraft water distribution systems is studied using two stainless steel water subsystems. One subsystem has an iodine level of 2.5 mg/L maintained by an iodinated ion-exchange resin. The other subsystem has no iodine added. Stainless steel coupons are removed from each system to monitor biofilm formation. Results from the first six months of operation indicate that 2.5 mg/L of iodine has limited the number of viable bacteria that can be recovered from the iodinated subsystem. Epifluorescence microscopy of the coupons taken from this subsystem, however, indicates some evidence of microbial colonization after 15 weeks of operation. Numerous bacteria have been continually removed from both the water samples and the coupons taken from the noniodinated subsystem after only 3 weeks of operation.

  14. Long Duration Life Test of Propylene Glycol Water Based Thermal Fluid Within Thermal Control Loop

    Science.gov (United States)

    Le, Hung; Hill, Charles; Stephan, Ryan A.

    2010-01-01

    Evaluations of thermal properties and resistance to microbial growth concluded that 50% Propylene Glycol (PG)-based fluid and 50% de-ionized water mixture was desirable for use as a fluid within a vehicle s thermal control loop. However, previous testing with a commercial mixture of PG and water containing phosphate corrosion inhibitors resulted in corrosion of aluminum within the test system and instability of the test fluid. This paper describes a follow-on long duration testing and analysis of 50% Propylene Glycol (PG)-based fluid and 50% de-ionized water mixture with inorganic corrosion inhibitors used in place of phosphates. The test evaluates the long-term fluid stability and resistance to microbial and chemical changes

  15. Dominant processes controlling water chemistry of the Pecos River in American southwest

    Science.gov (United States)

    Yuan, Fasong; Miyamoto, Seiichi

    2005-09-01

    Here we show an analysis of river flow and water chemistry data from eleven gauging stations along the Pecos River in eastern New Mexico and western Texas, with time spanning 1959-2002. Analysis of spatial relationship between the long-term average flow and total dissolved solids (TDS) concentration allows us to illuminate four major processes controlling river chemistry, namely saline water addition, evaporative concentration with salt gain or loss, dilution with salt gain or loss, and salt storage. Of the 10 river reaches studied, six reaches exhibit the process dominated by evaporative concentration or freshwater dilution with little change in salt load. Four reaches show considerable salt gains or losses that are induced by surface-ground water interactions. This analysis suggests that the evaporative concentration and freshwater dilution are the prevailing mechanisms, but local processes (e.g., variations in hydrologic flowpath and lithologic formation) also play an important role in regulating the hydrochemistry of the Pecos River.

  16. Behavioral Determinants of Switching to Arsenic-Safe Water Wells: An Analysis of a Randomized Controlled Trial of Health Education Interventions Coupled With Water Arsenic Testing

    Science.gov (United States)

    George, Christine Marie; Inauen, Jennifer; Perin, Jamie; Tighe, Jennifer; Hasan, Khaled; Zheng, Yan

    2017-01-01

    More than 100 million people globally are estimated to be exposed to arsenic in drinking water that exceeds the World Health Organization guideline of 10 µg/L. In an effort to develop and test a low-cost sustainable approach for water arsenic testing in Bangladesh, we conducted a randomized controlled trial which found arsenic educational…

  17. The ethno-politics of water security: contestations of ethnicity and gender in strategies to control water in the Andes of Peru

    NARCIS (Netherlands)

    Vera-Delgado, J.

    2011-01-01

    This thesis is the result of a multidisciplinary research which tries to explain water injustices and the threats to water rights access and control experienced by indigenous peasants of the Peruvian Andes. It attempts to contribute to the analysis of the interactions between ethnicity and gender, a

  18. Behavioral Determinants of Switching to Arsenic-Safe Water Wells: An Analysis of a Randomized Controlled Trial of Health Education Interventions Coupled With Water Arsenic Testing

    Science.gov (United States)

    George, Christine Marie; Inauen, Jennifer; Perin, Jamie; Tighe, Jennifer; Hasan, Khaled; Zheng, Yan

    2017-01-01

    More than 100 million people globally are estimated to be exposed to arsenic in drinking water that exceeds the World Health Organization guideline of 10 µg/L. In an effort to develop and test a low-cost sustainable approach for water arsenic testing in Bangladesh, we conducted a randomized controlled trial which found arsenic educational…

  19. Reducing diarrhea through the use of household-based ceramic water filters: a randomized, controlled trial in rural Bolivia.

    Science.gov (United States)

    Clasen, Thomas F; Brown, Joseph; Collin, Simon; Suntura, Oscar; Cairncross, Sandy

    2004-06-01

    Ceramic water filters have been identified as one of the most promising and accessible technologies for treating water at the household level. In a six-month trial, water filters were distributed randomly to half of the 50 participating households in a rural community in Bolivia; the remaining households continued to use customary water handling practices and served as controls. In four rounds of sampling following distribution of the filters, 100% of the 96 water samples from the filter households were free of thermotolerant coliforms compared with 15.5% of the control household samples. Diarrheal disease risk for individuals in intervention households was 70% lower than for controls (95% confidence interval [CI] = 53-80%; P ceramic water filters enable low-income households to treat and maintain the microbiologic quality of their drinking water.

  20. Assessing trichloromethane formation and control in algal-stimulated waters amended with nitrogen and phosphorus.

    Science.gov (United States)

    Mash, Clinton A; Winston, Byron A; Meints Ii, David A; Pifer, Ashley D; Scott, J Thad; Zhang, Wen; Fairey, Julian L

    2014-05-01

    Nitrogen (N) and phosphorus (P) enrichments can stimulate algal growth in drinking water sources, which can cause increased production of disinfection byproduct (DBP) precursors. However, the effect of systematic N and P enrichments on DBP formation and control has not been adequately studied. In this work, we enriched samples from a drinking water source - sampled on April 5, May 30, and August 19, 2013 - with N and P to stimulate algal growth at N : P ratios covering almost five orders of magnitude (0.2-4429). To simulate DBP-precursor removal processes at drinking water treatment plants (DWTPs), the samples were treated with ClO2 followed by alum coagulation prior to free chlorine addition to assess the DBP formation potential (FP). Trichloromethane (TCM) was the predominant DBP formed and the TCMFP was the highest at intermediate N : P molar ratios (∼10 to 50), which corresponded with the peak in algal biomass, as measured by chlorophyll-a (Chl-a). Algal biomass was P-limited throughout the study period, and co-limited by N for the August 19 sampling set. The differences in TCMFP between the raw and treated waters decreased with increasing P amendment, indicating that ClO2 and alum coagulation became less effective for TCM precursor removal as algal biomass increased. This study highlights the impact of nutrient enrichments on TCM formation and control and has implications for nutrient management strategies related to source water protection and for DWTPs that use source waters increasingly enriched with N and P.

  1. Research and control of well water pollution in high esophageal cancer areas

    Institute of Scientific and Technical Information of China (English)

    Xiu-Lan Zhang; Xiu-Lan Bai; Bing Zhang; Xing Zhang; Zhi-Feng Chen; Jun-Zhen Zhang; Shuo-Yuang Liang; Fan-Shu Men; Shu-Liang Zheng; Xiang-Ping Li

    2003-01-01

    AIM: In order to detect risk factors for esophageal cancer,a national research program was carried out during the Eighth Five-Year Plan (from 1991 to 1995). METHODS: Cixian County and Chichen County in Hebei Province were selected as the index and the control for the study fields with higher or lower incidence of esophagus cancer in China, respectively. In these areas, we investigated the pollution of three nitrogenous compounds in well water for drinking and the use of nitrogen fertilizer in farming. RESULTS: In well water, nitrate nitrogen, nitrite nitrogen and ammonia nitrogen were 8.77 mg/L, 0.014 mg/L and 0.009 mg/L in Cixian County in 1993, respectively. They were significantly higher than their levels (3.84 mg/L, 0.004 mg/L and 0.004 mg/L) in Chichen County (P<0.01, t=6.281,t=3.784,t=3.775). There was a trend that the nitrogenous compounds in well water increased from 1993 to 1996.The amount of nitrogen fertilizer used in farming was 787.6 kg per hectare land in Cixian County in 1991, significantly higher than 186 kg per hectare in Chichen County (t=9.603,P<0.001). CONCLUSION: These investigations indicate that the poilution of nitrogenous compounds in well water for drinking is closely related to the use of nitrogen fertlizer in farming, and there is a significantly positive correlation between the level of three nitrogenous compounds in well water and the mortality ofesophageal cancer (correlation coefficient =0.5992). We suggest that improvement of well system for drinking water quality should be an effective measure for esophageal cancer prevention and control in rural areas.

  2. Does eating slowly influence appetite and energy intake when water intake is controlled?

    Directory of Open Access Journals (Sweden)

    Andrade Ana M

    2012-11-01

    Full Text Available Abstract Background Slow eating has been associated with enhanced satiation, but also with increased water intake. Therefore, the role of water ingestion in regard to eating rate needs to be discerned. This study examined the influence of eating rate on appetite regulation and energy intake when water intake is controlled. Methods In a randomized design, slow and fast eating rates were compared on two occasions, in 30 women (22.7±1.2y; BMI=22.4±0.4kg/m2 who consumed an ad libitum mixed-macronutrient lunch with water (300 mL. Satiation was examined as the main outcome by measuring energy intake during meals. At designated times, subjects rated hunger, satiety, desire-to-eat, thirst, and meal palatability on visual analogue scales. Paired t-tests were used to compare hypothesis-driven outcomes. Appetite ratings were compared across time points and conditions by repeated measures analysis of variance (ANOVA using a within-subject model. Results Energy intake and appetite ratings did not differ between conditions at meal completion. However, subjects rated less hunger and tended to rate lower desire-to-eat and greater satiety at 1 hour following the slow condition. Conclusions Results tend to support a role of slow eating on decreased hunger and higher inter-meal satiety when water intake is controlled. However, the lack of significant differences in energy intake under these conditions indicates that water intake may account for the effects of eating rate on appetite regulation.

  3. Development of theoretical approaches to the control of a water-treatment system

    Science.gov (United States)

    Chiam, Tze Chao; Yih, Yuehwern; Mitchell, Cary

    2010-12-01

    The Advanced Life Support/NASA Specialized Center of Research and Training (ALS/NSCORT) focuses on research and development of technologies to support human habitation during space missions. This research was done as part of an effort to maintain crewmembers' water supply in a closed life-support system. The water subsystem was the primary focus of this study because water is one of the most expensive and important resources for human survival. This paper focuses on the application of previously-developed methodologies for controlling a water-treatment system. The water-treatment and usage model was set up based on the Baseline Value and Assumptions Document (BVAD) published by NASA. The conditions, or "states", of the system are captured hourly in the model. Control policies are defined in terms of treatment efficiencies. One control policy is to be used for the system at the beginning of each hour. A simulation is developed to study the impact of different control policies to this model. The Markov Decision Process (MDP) is used to aid the decision of choosing a policy to be used. In order for the MDP to pick the best policy, a state-space exploration technique, the Controlled Random Walk, is used for state-space exploration. This technique, together with re-initialization of initial system conditions, allow the system to visit a larger portion of the state space compared to some other techniques. In order to describe the state transitions, transition-probability matrices need to be computed. A probability-convergence technique is developed to minimize bias while computing these matrices. This technique is based on the Kullback-Leibler divergence measure, but modified for this application. A test case is constructed to assess the performance of best policies. Three scenarios with different levels of fluctuation, or disturbances, of water-consumption and treatment efficiencies are introduced in the test case. Results show that the best policies outperformed cases

  4. 78 FR 15007 - Notice of Open House-Draft Environmental Impact Statement for Revised Water Control Manuals for...

    Science.gov (United States)

    2013-03-08

    ... Revised Water Control Manuals for the Alabama-Coosa-Tallapoosa River Basin AGENCY: Department of the Army... Alabama-Coosa-Tallapoosa River Basin (ACT) Water Control Master Manual (Master Manual). The public comment... CONTACT: Mr. Lewis Sumner at telephone (251) 694-3857. SUPPLEMENTARY INFORMATION: The Master...

  5. 23 CFR 633.211 - Implementation of the Clean Air Act and the Federal Water Pollution Control Act.

    Science.gov (United States)

    2010-04-01

    ... Water Pollution Control Act. 633.211 Section 633.211 Highways FEDERAL HIGHWAY ADMINISTRATION, DEPARTMENT...) implementing requirements with respect to the Clean Air Act and the Federal Water Pollution Control Act are... Contracts (Appalachian Contracts) § 633.211 Implementation of the Clean Air Act and the Federal...

  6. Instability mechanism and control technology of soft rock roadway affected by mining and high confined water

    Institute of Scientific and Technical Information of China (English)

    Li Guichen; Jiang Zuohan; Lv Chuangxin; Huang Chao; Chen Gui; Li Mingyuan

    2015-01-01

    Based on deformation and failure characteristics of the second belt conveyor roadway at level II of Zhuxianzhuang coal mine, laboratory experiments, numerical calculation and field test were adopted to analyze the composition and microstructure of mudstone, the law of mudstone hydration and its strength weakening induced by water, the characteristics of surrounding rock deformation and failure under the action of confined water. Results showed that montmorillonite clay minerals accounted for as much as 76% of mudstone, with a large number of pores existing in the microstructure. Besides, as the molecular structure of montmorillonite changed, mudstone microstructure damage occurred with the macroscopic manifestation of its rheological instability. Weakening degree of confined water on residual strength of mudstone was almost 50%. The instability mechanism of soft rock roadway caused by high confined water is that surrounding rock circulates the process of ‘fracture-seepage-mud ding-closed’ twice, which weakens its strength and leads to roadway instability. A combined support technology, namely the, ‘high-toughness sealing layer+hollow grouting cables+full-length anchoring bolts with deep borehole’ was proposed. Based on field observation, the soft rock roadway was controlled effectively, which also verified the effectiveness of new control technology for surrounding rock.

  7. Case-control study of bladder cancer and drinking water arsenic in the western United States.

    Science.gov (United States)

    Steinmaus, Craig; Yuan, Yan; Bates, Michael N; Smith, Allan H

    2003-12-15

    Numerous epidemiologic investigations have identified links between high concentrations of arsenic in drinking water and cancer, although the risks at lower exposures are largely unknown. This paper presents the results of a case-control study of arsenic ingestion and bladder cancer in seven counties in the western United States. These counties contain the largest populations historically exposed to drinking water arsenic at concentrations near 100 microg/liter. All incident cases diagnosed from 1994 to 2000 were recruited. Individual data on water sources, water consumption patterns, smoking, and other factors were collected for 181 cases and 328 controls. Overall, no increased risks were identified for arsenic intakes greater than 80 microg/day (odds ratio=0.94, 95% confidence interval: 0.56, 1.57; linear trend, p=0.48). These risks are below predictions based on high dose studies from Taiwan. When the analysis was focused on exposures 40 or more years ago, an odds ratio of 3.67 (95% confidence interval: 1.43, 9.42; linear trend, p<0.01) was identified for intakes greater than 80 microg/day (median intake, 177 microg/day) in smokers. These data provide some evidence that smokers who ingest arsenic at concentrations near 200 microg/day may be at increased risk of bladder cancer.

  8. Evaluating Performance of Water Hammer Control Equipment using Hytran Software in Hasanlu Dam Pumping Station

    Directory of Open Access Journals (Sweden)

    Parisa Nazari

    2016-09-01

    Full Text Available Unsteady flows start from a steady state and end the other steady state condition. In water lines unsteady flows occur mainly due to the closure of valves, sudden pumps stops or sudden pumps starts. To prevent these losses, the major ways which can be used are pressure valves, air tanks and surge tanks. All various methods of controlling water hammer pursue a common goal, and that is to balance pressure from water hammer to adjust the pressure in an acceptable range in the network. In this paper, unsteady hydraulic flow control methods include protective measures such as the use of check valve and installation of air valves, air chambers and surge tanks are investigated and compared. And so that the1400 mm existing pipe line of Hasanlu dam pump station, can be simulated using Hytran software, and then minimum and maximum pressure due to the different choking in the throat connecting the main route was evaluated. The results presented that the use of check valve with built-in soft starter in the present case study reduces the positive and negative pressure caused by the water hammer phenomenon as possible value.

  9. Path-programmable water droplet manipulations on an adhesion controlled superhydrophobic surface

    Science.gov (United States)

    Seo, Jungmok; Lee, Seoung-Ki; Lee, Jaehong; Seung Lee, Jung; Kwon, Hyukho; Cho, Seung-Woo; Ahn, Jong-Hyun; Lee, Taeyoon

    2015-01-01

    Here, we developed a novel and facile method to control the local water adhesion force of a thin and stretchable superhydrophobic polydimethylsiloxane (PDMS) substrate with micro-pillar arrays that allows the individual manipulation of droplet motions including moving, merging and mixing. When a vacuum pressure was applied below the PDMS substrate, a local dimple structure was formed and the water adhesion force of structure was significantly changed owing to the dynamically varied pillar density. With the help of the lowered water adhesion force and the slope angle of the formed dimple structure, the motion of individual water droplets could be precisely controlled, which facilitated the creation of a droplet-based microfluidic platform capable of a programmable manipulation of droplets. We showed that the platform could be used in newer and emerging microfluidic operations such as surface-enhanced Raman spectroscopy with extremely high sensing capability (10−15 M) and in vitro small interfering RNA transfection with enhanced transfection efficiency of ~80%. PMID:26202206

  10. Fabrication of Superhydrophobic Surfaces with Controllable Electrical Conductivity and Water Adhesion.

    Science.gov (United States)

    Ye, Lijun; Guan, Jipeng; Li, Zhixiang; Zhao, Jingxin; Ye, Cuicui; You, Jichun; Li, Yongjin

    2017-02-14

    A facile and versatile strategy for fabricating superhydrophobic surfaces with controllable electrical conductivity and water adhesion is reported. "Vine-on-fence"-structured and cerebral cortex-like superhydrophobic surfaces are constructed by filtering a suspension of multiwalled carbon nanotubes (MWCNTs), using polyoxymethylene nonwovens as the filter paper. The nonwovens with micro- and nanoporous two-tier structures act as the skeleton, introducing a microscale structure. The MWCNTs act as nanoscale structures, creating hierarchical surface roughness. The surface topography and the electrical conductivity of the superhydrophobic surfaces are controlled by varying the MWCNT loading. The vine-on-fence-structured surfaces exhibit "sticky" superhydrophobicity with high water adhesion. The cerebral cortex-like surfaces exhibit self-cleaning properties with low water adhesion. The as-prepared superhydrophobic surfaces are chemically resistant to acidic and alkaline environments of pH 2-12. They therefore have potential in applications such as droplet-based microreactors and thin-film microextraction. These findings aid our understanding of the role that surface topography plays in the design and fabrication of superhydrophobic surfaces with different water-adhesion properties.

  11. Water

    Science.gov (United States)

    Leopold, Luna Bergere; Baldwin, Helene L.

    1962-01-01

    What do you use water for?If someone asked you this question you would probably think right away of water for drinking. Then you would think of water for bathing, brushing teeth, flushing the toilet. Your list would get longer as you thought of water for cooking, washing the dishes, running the garbage grinder. Water for lawn watering, for play pools, for swimming pools, for washing the car and the dog. Water for washing machines and for air conditioning. You can hardly do without water for fun and pleasure—water for swimming, boating, fishing, water-skiing, and skin diving. In school or the public library, you need water to wash your hands, or to have a drink. If your home or school bursts into flames, quantities of water are needed to put it out.In fact, life to Americans is unthinkable without large supplies of fresh, clean water. If you give the matter a little thought, you will realize that people in many countries, even in our own, may suffer from disease and dirt simply because their homes are not equipped with running water. Imagine your own town if for some reason - an explosion, perhaps - water service were cut off for a week or several weeks. You would have to drive or walk to a neighboring town and bring water back in pails. Certainly if people had to carry water themselves they might not be inclined to bathe very often; washing clothes would be a real chore.Nothing can live without water. The earth is covered by water over three-fourths of its surface - water as a liquid in rivers, lakes and oceans, and water as ice and snow on the tops of high mountains and in the polar regions. Only one-quarter of our bodies is bone and muscle; the other three-fourths is made of water. We need water to live, and so do plants and animals. People and animals can live a long time without food, but without water they die in a few days. Without water, everything would die, and the world would turn into a huge desert.

  12. Equilibrating Pressure with Auto-Control Valve in Water Distribution Networks

    Institute of Scientific and Technical Information of China (English)

    张宏伟; 闫晓强; 张丽

    2003-01-01

    This paper probes into the feasibility of equilibrating pressure of water distribution network through using auto-control valves in theory and in the economy. An optimal valve control model is designed to minimize the sum of squares of residual pressure in the network. Such an analog simulation has been performed on the year 2003 programming network of a certain littoral district in North China, through which this paper confirms that it is feasible to equilibrate pressure with auto-control valves in theory. The research work has brought about a discovery of applicable conditions of valves in economic feasibility, which avoids a great economic loss due to the wild use of auto-control valve. In addition, simulated annealing algorithm is applied to optimize valve settings and shown to identify global optimum or near-optimum.

  13. Modelling and control of cholera on networks with a common water source.

    Science.gov (United States)

    Shuai, Zhisheng; van den Driessche, P

    2015-01-01

    A mathematical model is formulated for the transmission and spread of cholera in a heterogeneous host population that consists of several patches of homogeneous host populations sharing a common water source. The basic reproduction number ℛ0 is derived and shown to determine whether or not cholera dies out. Explicit formulas are derived for target/type reproduction numbers that measure the control strategies required to eradicate cholera from all patches.

  14. A New Concept of Ultrafiltration Fouling Control: Backwashing with Low Ionic Strength Water

    OpenAIRE

    Li, S.

    2011-01-01

    Ultrafiltration (UF) is a proven technology in water treatment nowadays. However, fouling remains a major challenge in the operation of UF, especially in regard to colloidal NOM fouling. In general, a number of colloidal NOM fouling mechanisms may occur, such as adsorption, gel formation. Colloidal NOM fouling is influenced by multivalent cations, ionic strength and pH. In order to control membrane fouling, different pretreatments such as powder activated carbon adsorption, lime softening, io...

  15. Monitoring the anaerobic treatment of waste waters; Control en la depuracion anaerobia de aguas residuales

    Energy Technology Data Exchange (ETDEWEB)

    Leon de Mora, C.; Molina Cantero, F.J.; Romero Galey, F.J.; Gomez Banderas, J.M. [Dpto. Tecnologia Electronica. Esc. Univ. Politec. Sevilla, Sevilla, (Spain)

    1997-04-01

    This article describes the results obtained in developing a system for monitoring sewage treatment. The system, supported by a PC, includes a fuzzy logic control algorithm for monitoring the anaerobic treatment of waste waters on the basis of data from sensors attached to an industrial robot (PLC). Its most outstanding features is that it is also capable of evaluating new monitoring strategies using parameters not originally included. (Author) 6 refs.

  16. A New Concept of Ultrafiltration Fouling Control: Backwashing with Low Ionic Strength Water

    OpenAIRE

    Li, S.

    2011-01-01

    Ultrafiltration (UF) is a proven technology in water treatment nowadays. However, fouling remains a major challenge in the operation of UF, especially in regard to colloidal NOM fouling. In general, a number of colloidal NOM fouling mechanisms may occur, such as adsorption, gel formation. Colloidal NOM fouling is influenced by multivalent cations, ionic strength and pH. In order to control membrane fouling, different pretreatments such as powder activated carbon adsorption, lime softening, io...

  17. Control of expansive growth in water deficit: from phenotyping to field simulations

    OpenAIRE

    Parent, Boris; Cabrera Bosquet, Llorenç; Cané, Maria Angela; Chaumont, François; Alvarez Prado, Santiago; Caldeira, Cecilio Frois; Lacube, Sébastien; Fleury, Delphine; Welcker, Claude; Tuberosa, Roberto; Tardieu, Francois

    2015-01-01

    Maintenance of expansive growth under water deficit has been selected as a key target trait of DROPS because of its early response in drying conditions, its large genetic variability, its partially common control with reproductive growth and its consequences on light interception and transpiration. Development of methods to measure shoot growth in Phenotyping platforms (PhenoArch and Phenodyn, M3P, Montpellier, France; The Plant Accelerator, Adelaide, Australia) allowed identification of a...

  18. 45Ca uptake from water by snails (Lymnaea vulgaris) in control and detergent-polluted samples.

    Science.gov (United States)

    Misra, V; Lal, H; Viswanathan, P N; Murti, C R

    1984-02-01

    A biostatic assay method involving 45Ca uptake into shells and tissues of snails (Lymnaea vulgaris) in 72 hr was developed to follow the effect of detergent-polluted water on ecosystems. There was a marked decrease in the 45Ca uptake by shells and tissues of linear alkyl benzene sulfonate-exposed animals as compared to controls. No change in 45Ca uptake was observed in dead shells, thereby excluding the possibility of passive exchange.

  19. A Water Hammer Protection Method for Mine Drainage System Based on Velocity Adjustment of Hydraulic Control Valve

    OpenAIRE

    Yanfei Kou; Jieming Yang; Ziming Kou

    2016-01-01

    Water hammer analysis is a fundamental work of pipeline systems design process for water distribution networks. The main characteristics for mine drainage system are the limited space and high cost of equipment and pipeline changing. In order to solve the protection problem of valve-closing water hammer for mine drainage system, a water hammer protection method for mine drainage system based on velocity adjustment of HCV (Hydraulic Control Valve) is proposed in this paper. The mathematic mode...

  20. Scheduling of Domestic Water Heater Power Demand for Maximizing PV Self-Consumption Using Model Predictive Control

    DEFF Research Database (Denmark)

    Sossan, Fabrizio; Kosek, Anna Magdalena; Martinenas, Sergejus

    2013-01-01

    to predict the future temperature of the water and it manages its state (on and off) according to the forecasted PV production, which are computed starting from forecast of the solar irradiance. Simulations for the proof of concept and for validating the proposed control strategy are proposed. Results......This paper presents a model predictive control (MPC) strategy for maximizing photo-voltaic (PV) selfconsumption in a household context exploiting the flexible demand of an electric water heater. The predictive controller uses a water heater model and forecast of the hot Water consumption in order...... of the control approach are compared with a traditional thermostatic controller using historical measurements of a 10 kW PV installation. Economic results based on the Italian self consumption tariffs are also reported. The model of the water heater complex is a mixed grey and white box and its parameters have...

  1. Fouling control mechanisms of demineralized water backwash: Reduction of charge screening and calcium bridging effects

    KAUST Repository

    Li, Sheng

    2011-12-01

    This paper investigates the impact of the ionic environment on the charge of colloidal natural organic matter (NOM) and ultrafiltration (UF) membranes (charge screening effect) and the calcium adsorption/bridging on new and fouled membranes (calcium bridging effect) by measuring the zeta potentials of membranes and colloidal NOM. Fouling experiments were conducted with natural water to determine whether the reduction of the charge screening effect and/or calcium bridging effect by backwashing with demineralized water can explain the observed reduction in fouling. Results show that the charge of both membranes and NOM, as measured by the zeta potential, became more negative at a lower pH and a lower concentration of electrolytes, in particular, divalent electrolytes. In addition, calcium also adsorbed onto the membranes, and consequently bridged colloidal NOM and membranes via binding with functional groups. The charge screening effect could be eliminated by flushing NOM and membranes with demineralized water, since a cation-free environment was established. However, only a limited amount of the calcium bridging connection was removed with demineralized water backwashes, so the calcium bridging effect mostly could not be eliminated. As demineralized water backwash was found to be effective in fouling control, it can be concluded that the reduction of the charge screening is the dominant mechanism for this. © 2011 Elsevier Ltd.

  2. Environmental Controls on Water Use Efficiency during Severe Drought in an Ozark Forest in Missouri, USA

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Bai [ORNL; Pallardy, Stephen G. [University of Missouri; Meyers, T. P. [NOAA ATDD; Gu, Lianhong [ORNL; Hanson, Paul J [ORNL; Wullschleger, Stan D [ORNL; Heuer, Mark [ATDD, NOAA; Hosman, K. P. [University of Missouri; Riggs, Jeffery S [ORNL; Sluss, Daniel Wayne [ORNL

    2010-01-01

    Environmental control of canopy-level water use efficiency (WUE) during drought was studied at an eddy flux site in an oak-hickory forest in central Missouri, USA. Two consecutive severe droughts in the summers of 2006 and 2007 afforded coverage of a broad range of environmental conditions. We stratified data so as to obtain sub-ranges that minimized cross-correlations among WUE-controlling factors. Our results showed that WUE was subject to control by atmospheric vapor pressure deficit (VPD), soil water potential (SWP) and the ratio of diffuse to total photosynthetically active radiation (If/It). The relationship between WUE and VPD was found to be an exponential decay function, whereas SWP and If/It appeared to control WUE in a linear fashion. VPD was a stronger controller than the other two factors since the former had much better correlations with WUE. It was also observed that the relationship between WUE and any single controlling factor was subject to regulations by the other two. One such example was an opposite response of WUE to SWP between low and high VPD values. An examination of WUE-SWP relationship within the full range of VPD obscured this difference. We also found that the slope of the linear regression between WUE and If/It, if determined within the full range of VPD, was exaggerated in comparison to that obtained in the sub-ranges of VPD. This was attributable to the fact that the two controlling parameters, VPD and If/It, were themselves correlated and direct controls of VPD on WUE were partially reflected in WUE-If/It relationship if considered within the full range of VPD.

  3. The Reduction of Distress Using Therapeutic Geothermal Water Procedures in a Randomized Controlled Clinical Trial

    Directory of Open Access Journals (Sweden)

    Lolita Rapolienė

    2015-01-01

    Full Text Available Stress is an element of each human’s life and an indicator of its quality. Thermal mineral waters have been used empirically for the treatment of different diseases for centuries. Aim of the Study. To investigate the effects of highly mineralised geothermal water balneotherapy on distress and health risk. Methodology. A randomized controlled clinical trial was performed with 130 seafarers: 65 underwent 2 weeks of balneotherapy with 108 g/L full-mineralisation bath treatment; the others were in control group. The effect of distress was measured using the General Symptoms Distress Scale. Factorial and logistic regression analyses were used for statistical analysis. Results. A significant positive effect on distress (P<0.001 was established after 2 weeks of treatment: the number of stress symptoms declined by 60%, while the intensity of stress symptoms reduced by 41%, and the control improved by 32%. Health risks caused by distress were reduced, and resources increased, whereas the probability of general health risk decreased by 18% (P=0.01. Conclusion. Balneotherapy with highly mineralised geothermal water reduces distress, by reducing the health risk posed by distress by 26%, increasing the health resources by 11%, and reducing probability of general health risk by 18%. Balneotherapy is an effective preventive tool and can take a significant place in integrative medicine.

  4. The Reduction of Distress Using Therapeutic Geothermal Water Procedures in a Randomized Controlled Clinical Trial

    Science.gov (United States)

    Rapolienė, Lolita; Razbadauskas, Artūras; Jurgelėnas, Antanas

    2015-01-01

    Stress is an element of each human's life and an indicator of its quality. Thermal mineral waters have been used empirically for the treatment of different diseases for centuries. Aim of the Study. To investigate the effects of highly mineralised geothermal water balneotherapy on distress and health risk. Methodology. A randomized controlled clinical trial was performed with 130 seafarers: 65 underwent 2 weeks of balneotherapy with 108 g/L full-mineralisation bath treatment; the others were in control group. The effect of distress was measured using the General Symptoms Distress Scale. Factorial and logistic regression analyses were used for statistical analysis. Results. A significant positive effect on distress (P < 0.001) was established after 2 weeks of treatment: the number of stress symptoms declined by 60%, while the intensity of stress symptoms reduced by 41%, and the control improved by 32%. Health risks caused by distress were reduced, and resources increased, whereas the probability of general health risk decreased by 18% (P = 0.01). Conclusion. Balneotherapy with highly mineralised geothermal water reduces distress, by reducing the health risk posed by distress by 26%, increasing the health resources by 11%, and reducing probability of general health risk by 18%. Balneotherapy is an effective preventive tool and can take a significant place in integrative medicine. PMID:25866680

  5. Experimental Investigation on the Basic Law of Hydraulic Fracturing After Water Pressure Control Blasting

    Science.gov (United States)

    Huang, Bingxiang; Li, Pengfeng; Ma, Jian; Chen, Shuliang

    2014-07-01

    Because of the advantages of integrating water pressure blasting and hydraulic fracturing, the use of hydraulic fracturing after water pressure control blasting is a method that is used to fully transform the structure of a coal-rock mass by increasing the number and range of hydraulic cracks. An experiment to study hydraulic fracturing after water pressure blasting on cement mortar samples (300 × 300 × 300 mm3) was conducted using a large-sized true triaxial hydraulic fracturing experimental system. A traditional hydraulic fracturing experiment was also performed for comparison. The experimental results show that water pressure blasting produces many blasting cracks, and follow-up hydraulic fracturing forces blasting cracks to propagate further and to form numerous multidirectional hydraulic cracks. Four macroscopic main hydraulic cracks in total were noted along the borehole axial and radial directions on the sample surfaces. Axial and radial main failure planes induced by macroscopic main hydraulic cracks split the sample into three big parts. Meanwhile, numerous local hydraulic cracks were formed on the main failure planes, in different directions and of different types. Local hydraulic cracks are mainly of three types: local hydraulic crack bands, local branched hydraulic cracks, and axial layered cracks. Because local hydraulic cracks produce multiple local layered failure planes and lamellar ruptures inside the sample, the integrity of the sample decreases greatly. The formation and propagation process of many multidirectional hydraulic cracks is affected by a combination of water pressure blasting, water pressure of fracturing, and the stress field of the surrounding rock. To a certain degree, the stress field of surrounding rock guides the formation and propagation process of the blasting crack and the follow-up hydraulic crack. Following hydraulic fracturing that has been conducted after water pressure blasting, the integrity of the sample is found to

  6. Can an Alder Disease Influence the Controls of Ecosystem Water Flux?

    Science.gov (United States)

    Rohrs-Richey, J. K.; Mulder, C. P.; Ruess, R. W.; Winton, L. M.; Stanosz, G. R.

    2007-12-01

    In Alaska, nitrogen-fixing shrubs (Alnus spp.) comprise a large component of the vegetation and are important for water and energy flux in the Alaskan tundra, the Interior boreal forest, and south-central Alaska. Recently there has been high incidence and severity of a canker disease on Alnus which alters small scale controls (e.g., leaves, branches) of water and carbon flux and may have ecosystem scale effects in severely diseased areas. The fungal pathogen, Valsa melanodiscus (anamorph =Cytospora umbrina), kills active xylem and phloem, causes long, girdling cankers on stems, and is frequently associated with stem mortality in the thin leaf alder (Alnus tenuifolia) and green alder (Alnus crispa). We are just beginning to understand how this canker disease affects the physiology of its host and the implications for water loss and carbon fixation. An inoculation experiment at the University of Alaska is currently being conducted on well-watered and water-limited green alders to: 1) monitor the response of the water transport system to infection and canker development; 2) assess the ability of colonized alders to adjust water use efficiency; and 3) measure the effect of canker development on photosynthesis. Only 4 weeks after inoculation, stems (3-5 mm diam.) with incipient cankers had an overall reduction in total daily water loss and up to 50 percent decrease in daily peak water loss. Stems with incipient cankers were also unable to attain the maximum photosynthetic rate of healthy stems, and had lower light saturation points and quantum efficiencies. Further quantification of these relationships is underway. This study, in combination with recent field measurements of sapflow, will allow us to estimate the impact of varying degrees of disease severity on stand-level water flux. Alders are a keystone species and are currently responding to climate change by expanding into the Alaska tundra, increasing abundance in northern Alaska, and migrating into river

  7. Vapour pressure deficit control in relation to water transport and water productivity in greenhouse tomato production during summer

    Science.gov (United States)

    Zhang, Dalong; Du, Qingjie; Zhang, Zhi; Jiao, Xiaocong; Song, Xiaoming; Li, Jianming

    2017-01-01

    Although atmospheric vapour pressure deficit (VPD) has been widely recognized as the evaporative driving force for water transport, the potential to reduce plant water consumption and improve water productivity by regulating VPD is highly uncertain. To bridge this gap, water transport in combination with plant productivity was examined in tomato (Solanum lycopersicum L.) plants grown under contrasting VPD gradients. The driving force for water transport was substantially reduced in low-VPD treatment, which consequently decreased water loss rate and moderated plant water stress: leaf desiccation, hydraulic limitation and excessive negative water potential were prevented by maintaining water balance. Alleviation in water stress by reducing VPD sustained stomatal function and photosynthesis, with concomitant improvements in biomass and fruit production. From physiological perspectives, suppression of the driving force and water flow rate substantially reduced cumulative transpiration by 19.9%. In accordance with physiological principles, irrigation water use efficiency as criterions of biomass and fruit yield in low-VPD treatment was significantly increased by 36.8% and 39.1%, respectively. The reduction in irrigation was counterbalanced by input of fogging water to some extent. Net water saving can be increased by enabling greater planting densities and improving the evaporative efficiency of the mechanical system. PMID:28266524

  8. The Impact of Water, Sanitation and Hygiene Interventions to Control Cholera: A Systematic Review

    Science.gov (United States)

    Taylor, Dawn L.; Kahawita, Tanya M.; Cairncross, Sandy; Ensink, Jeroen H. J.

    2015-01-01

    Background and Methods Cholera remains a significant threat to global public health with an estimated 100,000 deaths per year. Water, sanitation and hygiene (WASH) interventions are frequently employed to control outbreaks though evidence regarding their effectiveness is often missing. This paper presents a systematic literature review investigating the function, use and impact of WASH interventions implemented to control cholera. Results The review yielded eighteen studies and of the five studies reporting on health impact, four reported outcomes associated with water treatment at the point of use, and one with the provision of improved water and sanitation infrastructure. Furthermore, whilst the reporting of function and use of interventions has become more common in recent publications, the quality of studies remains low. The majority of papers (>60%) described water quality interventions, with those at the water source focussing on ineffective chlorination of wells, and the remaining being applied at the point of use. Interventions such as filtration, solar disinfection and distribution of chlorine products were implemented but their limitations regarding the need for adherence and correct use were not fully considered. Hand washing and hygiene interventions address several transmission routes but only 22% of the studies attempted to evaluate them and mainly focussed on improving knowledge and uptake of messages but not necessarily translating this into safer practices. The use and maintenance of safe water storage containers was only evaluated once, under-estimating the considerable potential for contamination between collection and use. This problem was confirmed in another study evaluating methods of container disinfection. One study investigated uptake of household disinfection kits which were accepted by the target population. A single study in an endemic setting compared a combination of interventions to improve water and sanitation infrastructure, and

  9. The Impact of Water, Sanitation and Hygiene Interventions to Control Cholera: A Systematic Review.

    Directory of Open Access Journals (Sweden)

    Dawn L Taylor

    Full Text Available Cholera remains a significant threat to global public health with an estimated 100,000 deaths per year. Water, sanitation and hygiene (WASH interventions are frequently employed to control outbreaks though evidence regarding their effectiveness is often missing. This paper presents a systematic literature review investigating the function, use and impact of WASH interventions implemented to control cholera.The review yielded eighteen studies and of the five studies reporting on health impact, four reported outcomes associated with water treatment at the point of use, and one with the provision of improved water and sanitation infrastructure. Furthermore, whilst the reporting of function and use of interventions has become more common in recent publications, the quality of studies remains low. The majority of papers (>60% described water quality interventions, with those at the water source focussing on ineffective chlorination of wells, and the remaining being applied at the point of use. Interventions such as filtration, solar disinfection and distribution of chlorine products were implemented but their limitations regarding the need for adherence and correct use were not fully considered. Hand washing and hygiene interventions address several transmission routes but only 22% of the studies attempted to evaluate them and mainly focussed on improving knowledge and uptake of messages but not necessarily translating this into safer practices. The use and maintenance of safe water storage containers was only evaluated once, under-estimating the considerable potential for contamination between collection and use. This problem was confirmed in another study evaluating methods of container disinfection. One study investigated uptake of household disinfection kits which were accepted by the target population. A single study in an endemic setting compared a combination of interventions to improve water and sanitation infrastructure, and the resulting

  10. Water

    Science.gov (United States)

    ... Lead Poisoning Prevention Training Center (HHLPPTC) Training Tracks Water Language: English Español (Spanish) Recommend on Facebook Tweet Share Compartir For information about lead in water in Flint, MI, please visit http://www.phe. ...

  11. Study on the introduction of hazard analysis and critical control point (HACCP) concept of the water quality management in water supply systems.

    Science.gov (United States)

    Yokoi, H; Embutsu, I; Yoda, M; Waseda, K

    2006-01-01

    In the latest revision in 2004, the 3rd edition, the Water Safety Plans (WSP) was newly introduced into the World Health Organization (WHO) Guidelines for Drinking Water Quality. The Hazard analysis and critical control point (HACCP) is a basic concept that underlies the WSPs, and is also known as the product quality management method in the field of food and the medical manufacturing industries. In the amendments of the Drinking Water Quality Standards in Japan, water suppliers are required to reasonably achieve both safe water and efficient water quality management. Therefore, the HACCP concept is focused as an adequate management method covering a whole process of water supply systems, in a systematic way. The purpose of this study is to investigate a practical procedure in introducing the HACCP into water quality management in Japan. In comparison to conventional applications of the HACCP, unmanageable variations of raw water quality, continuous treatment and supply, and numerous standards of water quality items need to be considered. The HACCP system is expected to achieve a quick response to improvements in water quality, accountability towards consumers and a decrease in accidents.

  12. Automatic controller to water plants Acionador automático para irrigar plantas

    Directory of Open Access Journals (Sweden)

    Leonardo Oliveira Medici

    2010-12-01

    Full Text Available Despite the massive demand of water for plant irrigation, there are few devices being used in the automation of this process in agriculture. This work evaluates a simple controller to water plants automatically that can be set up with low cost commercial materials, which are large-scale produced. This controller is composed by a ceramic capsule used in common domestic water filters; a plastic tube around 1.5 m long, and a pressostate used in domestic washing machines. The capsule and the pressostate are connected through the tube so that all parts are filled with water. The ceramic capsule is the sensor of the controller and has to be placed into the plant substrate. The pressostate has to be placed below the sensor and the lower it is, the higher is the water tension to start the irrigation, since the lower is the pressostate the higher is the water column above it and, therefore, the higher is the tension inside the ceramic cup to pull up the water column. The controller was evaluated in the control of drip irrigation for small containers filled with commercial organic substrate or soil. Linear regressions explained the relationship between the position of pressostate and the maximum water tension in the commercial substrate (p A despeito da enorme demanda por água na irrigação de plantas, existem poucos aparelhos para automação deste processo sendo usados na agricultura. Avaliou-se um acionador automático para irrigação, o qual pode ser confeccionado com materiais comerciais de baixo custo, pois são produzidos em larga escala. Este acionador é composto por uma cápsula cerâmica usada em filtros de água domésticos; um tubo plástico com cerca de um metro e meio de comprimento e um pressostato de máquinas de lavar roupas domésticas. A cápsula e o pressostato são conectados pelo tubo de forma que todo o espaço interno seja preenchido com água. A cápsula é o sensor do acionador e deve ser posicionada dentro do substrato das

  13. Nonlinear control for core power of pressurized water nuclear reactors using constant axial offset strategy

    Directory of Open Access Journals (Sweden)

    Gholam Reza Ansarifar

    2015-12-01

    Full Text Available One of the most important operations in nuclear power plants is load following, in which an imbalance of axial power distribution induces xenon oscillations. These oscillations must be maintained within acceptable limits otherwise the nuclear power plant could become unstable. Therefore, bounded xenon oscillation is considered to be a constraint for the load following operation. In this paper, the design of a sliding mode control (SMC, which is a robust nonlinear controller, is presented. SMC is a means to control pressurized water nuclear reactor (PWR power for the load following operation problem in a way that ensures xenon oscillations are kept bounded within acceptable limits. The proposed controller uses constant axial offset (AO strategy to ensure xenon oscillations remain bounded. The constant AO is a robust state constraint for the load following problem. The reactor core is simulated based on the two-point nuclear reactor model with a three delayed neutron groups. The stability analysis is given by means of the Lyapunov approach, thus the control system is guaranteed to be stable within a large range. The employed method is easy to implement in practical applications and moreover, the SMC exhibits the desired dynamic properties during the entire output-tracking process independent of perturbations. Simulation results are presented to demonstrate the effectiveness of the proposed controller in terms of performance, robustness, and stability. Results show that the proposed controller for the load following operation is so effective that the xenon oscillations are kept bounded in the given region.

  14. Nonlinear control for core power of pressurized water nuclear reactors using constant axial offset strategy

    Energy Technology Data Exchange (ETDEWEB)

    Ansarifar, Gholam Reza; Saadatzi, Saeed [Dept. of Nuclear Engineering, Faculty of Advanced Sciences and Technology, University of Isfahan, Isfahan (Iran, Islamic Republic of)

    2015-12-15

    One of the most important operations in nuclear power plants is load following, in which an imbalance of axial power distribution induces xenon oscillations. These oscillations must be maintained within acceptable limits otherwise the nuclear power plant could become unstable. Therefore, bounded xenon oscillation is considered to be a constraint for the load following operation. In this paper, the design of a sliding mode control (SMC), which is a robust nonlinear controller, is presented. SMC is a means to control pressurized water nuclear reactor (PWR) power for the load following operation problem in a way that ensures xenon oscillations are kept bounded within acceptable limits. The proposed controller uses constant axial offset (AO) strategy to ensure xenon oscillations remain bounded. The constant AO is a robust state constraint for the load following problem. The reactor core is simulated based on the two-point nuclear reactor model with a three delayed neutron groups. The stability analysis is given by means of the Lyapunov approach, thus the control system is guaranteed to be stable within a large range. The employed method is easy to implement in practical applications and moreover, the SMC exhibits the desired dynamic properties during the entire output-tracking process independent of perturbations. Simulation results are presented to demonstrate the effectiveness of the proposed controller in terms of performance, robustness, and stability. Results show that the proposed controller for the load following operation is so effective that the xenon oscillations are kept bounded in the given region.

  15. [Comparative study of some clinical and laboratory indicators in a group of patients using wells as source of drinking water and a control group using safe water].

    Science.gov (United States)

    Vasilescu, L; Ciochină, D A

    2011-01-01

    In time, well water, as a source of drinking and coking water, with physical-chemical, bacteriological, and biological indicators suggestive of alteration in water potability, determines complex, sometimes irreversible, metabolic disorders. Sixty individuals residing in a rural community were divided into 2 groups: study group -30 subjects using well water, and control group--30 subjects using safe water. For the study group the selection criteria were: age, sex, use of well water as drinking and cooking water, history suggestive of chronic poisoning (pregnancy course, birth weight, susceptibility to infectious agents, and current chronic diseases). In the study group, gestosis, prematurity, and altered body mass index are more frequent as compared to the subjects in the control group. The identified laboratory changes indicate moderate anemia, hepatic cytolysis, dyslipidemia, presence of nitrites in urine, and positive urine cultures. Long-term use of water with mineral constituents in excess, absent, or inadequate, the direct biological and chemical water pollution, or most frequently the indirect pollution through the soil determine, in time, complex, sometimes irreversible, metabolic disorders.

  16. Scenario-based fitted Q-iteration for adaptive control of water reservoir systems under uncertainty

    Science.gov (United States)

    Bertoni, Federica; Giuliani, Matteo; Castelletti, Andrea

    2017-04-01

    Over recent years, mathematical models have largely been used to support planning and management of water resources systems. Yet, the increasing uncertainties in their inputs - due to increased variability in the hydrological regimes - are a major challenge to the optimal operations of these systems. Such uncertainty, boosted by projected changing climate, violates the stationarity principle generally used for describing hydro-meteorological processes, which assumes time persisting statistical characteristics of a given variable as inferred by historical data. As this principle is unlikely to be valid in the future, the probability density function used for modeling stochastic disturbances (e.g., inflows) becomes an additional uncertain parameter of the problem, which can be described in a deterministic and set-membership based fashion. This study contributes a novel method for designing optimal, adaptive policies for controlling water reservoir systems under climate-related uncertainty. The proposed method, called scenario-based Fitted Q-Iteration (sFQI), extends the original Fitted Q-Iteration algorithm by enlarging the state space to include the space of the uncertain system's parameters (i.e., the uncertain climate scenarios). As a result, sFQI embeds the set-membership uncertainty of the future inflow scenarios in the action-value function and is able to approximate, with a single learning process, the optimal control policy associated to any scenario included in the uncertainty set. The method is demonstrated on a synthetic water system, consisting of a regulated lake operated for ensuring reliable water supply to downstream users. Numerical results show that the sFQI algorithm successfully identifies adaptive solutions to operate the system under different inflow scenarios, which outperform the control policy designed under historical conditions. Moreover, the sFQI policy generalizes over inflow scenarios not directly experienced during the policy design

  17. The Design of Water Level Controller in Electro-heating Water Dispensers%电加热饮水机的水位控制器设计

    Institute of Scientific and Technical Information of China (English)

    杨丽寰; 白晓梅

    2015-01-01

    设计了电加热饮水机的水位控制器,用74 HC138译码器控制的指示灯做为监视器件的水位监视电路;通过D锁存器控制三极管的导通或截止来控制继电器,进而实现基本控制功能的水位控制电路。该设计的原理是当水位低于下限水位A时,红灯亮危险,自动注水;注水到BC之间时,绿灯亮正常,自动停止注水;水位在上限C以上或 AB之间时,黄灯亮异常,可以通过触摸键手动注水、停水。本文首先确定了总体的设计方案,其次是单元电路的设计,包括供电电源电路的设计(电路参数的估算以及元器件的选择)、水位监视电路的设计和水位控制电路的设计。%This thesis presents the design of the water level controller in electric heating water dispensers. The design takes a 74 HC138 decoder as a monitor which controls light as the water level monitoring cir-cuit and a D latch to control the conduction of transistors or cut-off and then to control relay so as to real-ize the basic control of water level control circuit.The principle of the design is: when the water level reaches Level A,the minimum water level,the red light is on which signs the danger and at the same time water is automatically injected.When water reaches between B and C,the normal level,the green light gets on and the injection stops immediately.When the water level reaches over C or between A and B, yellow light anomalies,and the user can touch keys to get water injected or stop injection.The paper first gives the general design and then shows the unit circuit design including the design of the power supply circuit (circuit parameters estimation and components selection),the design of water level monitor cir-cuit,and the design of water level control circuit.

  18. Water Chemistry Control System for Recovery of Damaged and Degraded Spent Fuel

    Energy Technology Data Exchange (ETDEWEB)

    Sindelar, R.; Fisher, D.; Thomas, J.

    2011-02-18

    The International Atomic Energy Agency (IAEA) and the government of Serbia have led the project cosponsored by the U.S, Russia, European Commission, and others to repackage and repatriate approximately 8000 spent fuel elements from the RA reactor fuel storage basins at the VIN?A Institute of Nuclear Sciences to Russia for reprocessing. The repackaging and transportation activities were implemented by a Russian consortium which includes the Sosny Company, Tekhsnabeksport (TENEX) and Mayak Production Association. High activity of the water of the fuel storage basin posed serious risk and challenges to the fuel removal from storage containers and repackaging for transportation. The risk centered on personnel exposure, even above the basin water, due to the high water activity levels caused by Cs-137 leached from fuel elements with failed cladding. A team of engineers from the U.S. DOE-NNSA's Global Threat Reduction Initiative, the Vinca Institute, and the IAEA performed the design, development, and deployment of a compact underwater water chemistry control system (WCCS) to remove the Cs-137 from the basin water and enable personnel safety above the basin water for repackaging operations. Key elements of the WCCS system included filters, multiple columns containing an inorganic sorbent, submersible pumps and flow meters. All system components were designed to be remotely serviceable and replaceable. The system was assembled and successfully deployed at the Vinca basin to support the fuel removal and repackaging activities. Following the successful operations, the Cs-137 is now safely contained and consolidated on the zeolite sorbent used in the columns of the WCCS, and the fuel has been removed from the basins. This paper reviews the functional requirements, design, and deployment of the WCCS.

  19. The challenge of improving boiling: lessons learned from a randomized controlled trial of water pasteurization and safe storage in Peru.

    Science.gov (United States)

    Heitzinger, K; Rocha, C A; Quick, R E; Montano, S M; Tilley, D H; Mock, C N; Carrasco, A J; Cabrera, R M; Hawes, S E

    2016-07-01

    Boiling is the most common method of household water treatment in developing countries; however, it is not always effectively practised. We conducted a randomized controlled trial among 210 households to assess the effectiveness of water pasteurization and safe-storage interventions in reducing Escherichia coli contamination of household drinking water in a water-boiling population in rural Peru. Households were randomized to receive either a safe-storage container or a safe-storage container plus water pasteurization indicator or to a control group. During a 13-week follow-up period, households that received a safe-storage container and water pasteurization indicator did not have a significantly different prevalence of stored drinking-water contamination relative to the control group [prevalence ratio (PR) 1·18, 95% confidence interval (CI) 0·92-1·52]. Similarly, receipt of a safe-storage container alone had no effect on prevalence of contamination (PR 1·02, 95% CI 0·79-1·31). Although use of water pasteurization indicators and locally available storage containers did not increase the safety of household drinking water in this study, future research could illuminate factors that facilitate the effective use of these interventions to improve water quality and reduce the risk of waterborne disease in populations that boil drinking water.

  20. Control of Hydrogen Generation from Water Molecules Dissociated by Activated Aluminum Particles Based on Fuzzy Logic

    Science.gov (United States)

    Maekawa, Koji; Takahara, Kenji; Kajiwara, Toshinori; Watanabe, Masao

    This paper proposes a control system to keep hydrogen generation by a reaction between water and activated aluminum particles at desired level. Because the activated aluminum particles are produced shredded aluminum sawdust, the characteristics of hydrogen generation vary depending on its samples. Therefore, the fuzzy control system to determine the quantum of the activated aluminum particles is designed based on the measured characteristics of hydrogen generation. Error form a desired value, error rate and dead time of the reaction are chosen as the labels of the proposed fuzzy membership functions. The reactor vessel that the activated aluminum particles are put into is developed to generate hydrogen continuously. Three types of aluminum particles of the characteristic are used for the experiments. The proposed system is confirmed to be useful for the control of hydrogen generation, coping with the effect of reacting characteristic changes according to the activated aluminum samples.

  1. An improved biofilter to control the dissolved organic nitrogen concentration during drinking water treatment.

    Science.gov (United States)

    Zhang, Huining; Gu, Li; Liu, Bing; Gan, Huihui; Zhang, Kefeng; Jin, Huixia; Yu, Xin

    2016-09-01

    Dissolved organic nitrogen (DON) is a key precursor of numerous disinfection by-products (DBPs), especially nitrogenous DBPs (N-DBPs) formed during disinfection in drinking water treatment. To effectively control DBPs, reduction of the DON concentration before the disinfection process is critical. Traditional biofilters can increase the DON concentration in the effluent, so an improved biofilter is needed. In this study, an improved biofilter was set up with two-layer columns using activated carbon and quartz sand under different influent patterns. Compared with the single-layer filter, the two-layer biofilter controlled the DON concentration more efficiently. The two-point influent biofilter controlled the DON concentration more effectively than the single-point influent biofilter. The improved biofilter resulted in an environment (including matrix, DO, and pH) suitable for microbial growth. Along the depth of the biofilter column, the environment affected the microbial biomass and microbial activity and thus affected the DON concentration.

  2. Small variations of soil properties control fire-induced water repellency

    Directory of Open Access Journals (Sweden)

    Jorge Mataix-Solera

    2014-03-01

    Full Text Available Fire induced soil water repellency (WR is controlled by many different factors (temperature reached, amount and type of fuel, etc.. Soil properties may determine the occurrence and intensity of this property in burned soils. The objectives of this paper are to make advances in the study of soil properties as key factors controlling the behaviour of fire-induced WR, and to study the impact of pre-fire SOM content and SOM quality in fire-induced soil WR. In this research, experimental laboratory burnings were carried out using soil samples from different sites with different lithologies, soil types and plant species. Soil samples taken from the same site differ only in quantity and quality of soil organic matter, as they were collected from under different plant species. All soil samples were heated in a muffle furnace at 200, 250, 300 and 350 ºC without the addition of any fuel load. WR was measured using the water drop penetration time test (WDPT. The results showed significant differences between soil types and plant species, indicating that small differences in soil properties may act as key factors controlling the development and persistence of WR reached, with burned soil samples ranging from wettable to extremely water repellent. The main soil property controlling the response was texture, specifically sand content. The quality of organic matter was also observed to have an effect, since soil samples from the same site with similar organic matter contents, but taken from beneath different plant species, showed different WR values after burning.

  3. UK experience in the monitoring and control of lead in drinking water.

    Science.gov (United States)

    Hayes, Colin R; Hydes, Owen D

    2012-09-01

    At the zonal scale (e.g. a city or town), random daytime (RDT) sampling succeeded in demonstrating both the need for corrective action and the benefits of optimised orthophosphate dosing for plumbosolvency control, despite initial concerns about sampling reproducibility. Stagnation sampling techniques were found to be less successful. Optimised treatment measures to minimise lead in drinking water, comprising orthophosphate at an optimum dose and at an appropriate pH, have succeeded in raising compliance with the future European Union (EU) lead standard of 10 μg/L from 80.4% in 1989-94 to 99.0% in 2010 across England and Wales, with compliance greater than 99.5% in some regions. There may be scope to achieve 99.8% compliance with 10 μg/L by further optimisation coupled to selective lead pipe removal, without widespread lead pipe removal. It is unlikely that optimised corrosion control, that includes the dosing of orthophosphate, will be capable of achieving a standard much lower than 10 μg/L for lead in drinking water. The experience gained in the UK provides an important reference for any other country or region that is considering its options for minimising lead in their drinking water supplies.

  4. Control factors and scale analysis of annual river water, sediments and carbon transport in China

    Science.gov (United States)

    Song, Chunlin; Wang, Genxu; Sun, Xiangyang; Chang, Ruiying; Mao, Tianxu

    2016-05-01

    Under the context of dramatic human disturbances on river system, the processes that control the transport of water, sediment, and carbon from river basins to coastal seas are not completely understood. Here we performed a quantitative synthesis for 121 sites across China to find control factors of annual river exports (Rc: runoff coefficient; TSSC: total suspended sediment concentration; TSSL: total suspended sediment loads; TOCL: total organic carbon loads) at different spatial scales. The results indicated that human activities such as dam construction and vegetation restoration might have a greater influence than climate on the transport of river sediment and carbon, although climate was a major driver of Rc. Multiple spatial scale analyses indicated that Rc increased from the small to medium scale by 20% and then decreased at the sizable scale by 20%. TSSC decreased from the small to sizeable scale but increase from the sizeable to large scales; however, TSSL significantly decreased from small (768 g·m‑2·a‑1) to medium spatial scale basins (258 g·m‑2·a‑1), and TOCL decreased from the medium to large scale. Our results will improve the understanding of water, sediment and carbon transport processes and contribute better water and land resources management strategies from different spatial scales.

  5. Water Level Loggers as a Low-Cost Tool for Monitoring of Stormwater Control Measures

    Directory of Open Access Journals (Sweden)

    Laura Toran

    2016-08-01

    Full Text Available Stormwater control measures (SCMs are a key component of watershed health in urbanized areas. SCMs are used to increase infiltration and reduce discharge to streams or storm sewer systems during rain events. Monitoring is important for the evaluation of design and causes of failure in SCMs. However, the expense of monitoring means it is not always included in stormwater control planning. This study shows how low-cost water level loggers can be used to answer certain questions about SCM performance. Five case studies are presented that use water level loggers to evaluate the overflow of basins, compare a traditional stormpipe trench with an infiltration trench, monitor timing of blue roof storage, show the effects of retrofitting a basin, and provide long term performance data. Water level loggers can be used to answer questions about the timing and location of stormwater overflows, which helps to evaluate the effectiveness of SCMs. More expensive monitoring and modeling can be used as a follow up if needed to more thoroughly assess a site. Nonetheless, low-cost monitoring can be a first step in identifying sites that need improvement or additional monitoring.

  6. Controls of catchments` sub-storage contributions to dynamic water quality patterns in the stream network

    Science.gov (United States)

    Schuetz, Tobias; Maike Hegenauer, Anja

    2016-04-01

    Water quality is usually observed either continuously at a few stations within a catchment or with few snapshot sampling campaigns throughout the whole stream network. Although we know that the depletion of catchment sub-storages can vary throughout the stream network according to their actual water content (spatial variability of actual storage conditions can be caused amongst others by unevenly distributed rainfall, storage size or spatial differences in soil characteristics and land use), we know little about the impact of this process on spatial water quality patterns. For summer low flow recession periods, when stream water composition can be crucial for aquatic ecosystem conditions and the exceedance of water quality thresholds, knowledge on the controls of the dynamic interplay of catchment storages and stream water composition might improve water quality management and the implementation of corresponding mitigation measures. We studied this process throughout the stream network of a first-order agricultural headwater catchment in south-western Germany during two summer low flow recession periods. The underlying geology of the study area is a deep layer of aeolian loess, whilst the dominating soil is a silty calcaric regosol with gleizations in the colluvium. The land use in the catchment is dominated by viniculture (63 %) and arable crops (18 %). Due to the dense drainpipe network within the catchment we could identify 12 sub-catchments contributing during summer low flow recession periods to total stream discharge. We continuously observed discharge, electrical conductivity and water temperatures for 8 of the sub-catchments and at the catchment outlet. This data set was accomplished by 10 snapshot campaigns where we sampled for water temperatures, electrical conductivity, major ions, pH and O2 throughout the stream network. Using either discharge concentration relationships or time dependent functions, we derived continuous export rates for all measures in

  7. Diagnosis of processes controlling water vapour in the tropical tropopause layer by a Lagrangian cirrus model

    Directory of Open Access Journals (Sweden)

    C. Ren

    2007-04-01

    Full Text Available We have developed a Lagrangian air-parcel cirrus model (LACM, to diagnose the processes controlling water in the tropical tropopause layer (TTL. LACM applies parameterised microphysics to air parcel trajectories. The parameterisation includes the homogeneous freezing of aerosol droplets, the growth/sublimation of ice particles, and sedimentation of ice particles, so capturing the main dehydration mechanism for air in the TTL. Rehydration is also considered by resetting the water vapour mixing ratio in an air parcel to the value at the point in the 4-D analysis/forecast data used to generate the trajectories, but only when certain conditions, indicative of convection, are satisfied. These conditions are imposed to confine what processes contribute to rehydration. The conditions act to restrict rehydration of the Lagrangian air parcels to regions where convective transport of water vapour from below is significant, at least to the extent that the analysis/forecast captures this process. The inclusion of hydration and dehydration mechanisms in LACM results in total water fields near tropical convection that have more of the "stripey" character of satellite observations of high cloud, than do either the ECMWF analysis or trajectories without microphysics.

    The mixing ratios of total water in the TTL, measured by a high-altitude aircraft over Brazil (during the TROCCINOX campaign, have been reconstructed by LACM using trajectories generated from ECMWF analysis. Two other Lagrangian reconstructions are also tested: linear interpolation of ECMWF analysed specific humidity onto the aircraft flight track, and instantaneous dehydration to the saturation vapour pressure over ice along trajectories. The reconstructed total water mixing ratios along aircraft flight tracks are compared with observations from the FISH total water hygrometer. Process-oriented analysis shows that modelled cirrus cloud events are responsible for dehydrating the air

  8. Metrological Analysis of Geopotential Gravity Field for Harbor Waterside Management and Water Quality Control

    Directory of Open Access Journals (Sweden)

    Osvaldo Faggioni

    2013-01-01

    Full Text Available Sea level oscillations are the superposition of many contributions. In particular, tide is a sea level up-down water motion basically depending on three different phenomena: the Earth-Moon-Sun gravitational relationship, the water surface fluid reaction to atmospheric meteorological dynamic, and the Newtonian vertical adjustment of the sea surface due to atmospheric pressure variations. The first tide component (astrotide is periodic and well known in all points of the Earth surface; the second one is directly related to the meteorological phenomenon, and then it is foreseeable; the Newtonian component, on the contrary, is not readily predictable by a general hydrostatic law, because the J factor that represents the Newtonian transfer (from the atmospheric weight to the consequent sea level is variable in each harbor area. The analysis of the gravity field permits to forecast the sea level variation due to meteorological tide events, and its metrological analysis highlights a compensation in the inverse hydrobarometric factor to be taken into account to correctly compensate atmospheric pressure variations in semibinding basins. This phenomenon has several consequences in Harbor Waterside management and in water quality control as shown by the reported case studies and introduces a new reference parameter: the so-called Water 1000.

  9. Occurrence and control of nitrogenous disinfection by-products in drinking water--a review.

    Science.gov (United States)

    Bond, Tom; Huang, Jin; Templeton, Michael R; Graham, Nigel

    2011-10-01

    The presence of nitrogenous disinfection by-products (N-DBPs), including nitrosamines, cyanogen halides, haloacetonitriles, haloacetamides and halonitromethanes, in drinking water is of concern due to their high genotoxicity and cytotoxicity compared with regulated DBPs. Occurrence of N-DBPs is likely to increase if water sources become impacted by wastewater and algae. Moreover, a shift from chlorination to chloramination, an option for water providers wanting to reduce regulated DBPs such as trihalomethanes (THMs) and haloacetic acids (HAAs), can also increase certain N-DBPs. This paper provides a critical review of the occurrence and control of N-DBPs. Data collated from surveys undertaken in the United States and Scotland were used to calculate that the sum of analysed halonitromethanes represented 3-4% of the mass of THMs on a median basis; with Pearson product moment correlation coefficients of 0.78 and 0.83 between formation of dihaloacetonitriles and that of THMs and HAAs respectively. The impact of water treatment processes on N-DBP formation is complex and variable. While coagulation and filtration are of moderate efficacy for the removal of N-DBP precursors, such as amino acids and amines, biofiltration, if used prior to disinfection, is particularly successful at removing cyanogen halide precursors. Oxidation before final disinfection can increase halonitromethane formation and decrease N-nitrosodimethylamine, and chloramination is likely to increase cyanogen halides and NDMA relative to chlorination. Copyright © 2011 Elsevier Ltd. All rights reserved.

  10. Intracutaneous or subcutaneous sterile water injection compared with blinded controls for pain management in labour.

    Science.gov (United States)

    Derry, Sheena; Straube, Sebastian; Moore, R Andrew; Hancock, Heather; Collins, Sally L

    2012-01-18

    Intracutaneous or subcutaneous injection of sterile water is rapidly gaining popularity as a method of pain relief in labour and it is therefore essential that it is properly evaluated. Adequate analgesia in labour is important to women worldwide. Sterile water injection is inexpensive, requires basic equipment, and appears to have few side effects. It is purported to work for labour pain. To determine the efficacy of sterile water injections for relief of pain (both typical contraction pain and intractable back pain) during labour compared to placebo (isotonic saline injections) or non-pharmacological interventions, and to identify any relevant effects on mode and timing of delivery, or safety of both mother and baby. We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (30 May 2011), MEDLINE, and EMBASE (January 2010 to 30 May 2011), together with reference lists in retrieved studies and review articles. We included randomised, double blind, controlled studies using intracutaneous or subcutaneous sterile water injections for pain relief during labour. There were no restrictions on birth place, parity, risk, age, weight, gestation, or stage of labour. Potential comparators were placebo (saline) and non-pharmacological interventions (e.g. hypnosis or biofeedback). Two review authors independently assessed eligibility and quality of trials, and extracted data. We resolved any disagreements or uncertainties by discussion with a third review author. Primary outcome measures were at least 50% pain relief, or at least 30%, pain relief, patient global impression of change of at least 'good', mode of delivery, perinatal morbidity and mortality, maternal complications and adverse events. Secondary outcomes were women with any pain relief, use of rescue analgesia, and treatment group average pain relief. We made explicit judgements about potential biases in the studies. We included seven studies, with 766 participants: four used intracutaneous

  11. Evaluation of some natural water-insoluble cellulosic material as lost circulation control additives in water-based drilling fluid

    Directory of Open Access Journals (Sweden)

    Ahmed Mohamed Alsabagh

    2015-12-01

    In this work, three natural water-insoluble cellulosic materials; peanut hulls, bagasse and sawdust were investigated as lost circulation control materials. One hundred and eight different LCM samples made of various materials were tested with mud. The experiments were conducted in a permeability plugging apparatus (PPA at a differential pressure of 100 psi and 300 psi, using 10, 60 and 90 ceramic discs. The performance of each LCM sample was determined based on the amount of spurt loss and total fluid loss of the mud according to the American Petroleum Institute (API standard. The obtained results showed that, the amount of the fluid loss depends on the LCM material, concentration and size distribution, testing results show that, the peanut gives the best results among the bagasse and sawdust, especially fine size which exhibited better results in the filtration characteristics due to the better filling properties of this size. Peanut hulls, bagasse and sawdust show a slight effect on the rheological properties of the mud. The results were discussed on light of particle size distribution.

  12. Field experiments of Controlled Drainage of agricultural clay soils show positive effects on water quantity (retention, runoff) and water quality (nitrate leaching).

    Science.gov (United States)

    schipper, peter; stuyt, lodewijk; straat, van der, andre; schans, van der, martin

    2014-05-01

    Despite best management practices, agriculture is still facing major challenges to reduce nutrients leaching to the aquatic environment. In deltas, most of total nutrient losses from artificially drained agricultural soils are discharged via drains. Controlled drainage is a promising measure to prevent drainage of valuable nutrients, improve water quality and agricultural yield and adapt to climate change (reduce peak runoff, manage water scarcity and drought). In The Netherlands, this technique has attracted much attention by water managers and farmers alike, yet field studies to determine the expected (positive) effects for Dutch conditions were scarce. Recently, a field experiment was set up on clay soils. Research questions were: how does controlled, subsurface drainage perform on clay soils? Will deeper tile drains function just as well? What are the effects on drain water quality (especially with respect to nitrogen and salt) and crop yield? An agricultural field on clay soils was used to test different tile drainage configurations. Four types of tile drainage systems were installed, all in duplicate: eight plots in total. Each plot has its own outlet to a control box, where equipment was installed to control drain discharge and to measure the flow, concentrations of macro-ions, pH, nitrogen, N-isotopes and heavy metals. In each plot, groundwater observation wells and suction cups are installed in the saturated and vadose zones, at different depths, and crop yield is determined. Four plots discharge into a hydrologic isolated ditch, enabling the determination of water- and nutrient balances. Automatic drain water samplers and innovative nitrate sensors were installed in four plots. These enable identification and unravelling so-called first flush effects (changes in concentrations after a storm event). Water-, chloride- and nitrogen balances have been set up, and the interaction between groundwater and surface water has been quantified. The hydrological

  13. Evidence for soil water control on carbon and water dynamics in European forests during the extremely dry year: 2003

    DEFF Research Database (Denmark)

    Granier, A.; Reichstein, M.; Breda, N.

    2007-01-01

    stand to estimate the water balance terms: trees and understorey transpiration, rainfall interception, throughfall, drainage in the different soil layers and soil water content. This model calculated the onset date, duration and intensity of the soil water shortage (called water stress) using measured...... European monitoring sites covering various forest ecosystem types and a large climatic range in order to characterise the consequences of this drought on ecosystems functioning. As soil water content in the root zone was only monitored in a few sites, a daily water balance model was implemented at each...... measured and modelled soil water content. Our analysis showed a wide spatial distribution of drought stress over Europe, with a maximum intensity within a large band extending from Portugal to NE Germany. Vapour fluxes in all the investigated sites were reduced by drought, due to stomatal closure, when...

  14. Obliquity-Controlled Water Vapor/Trace Gas Feedback in the Martian Greenhouse Cycle

    Science.gov (United States)

    Mischna, M. A.; Baker, V. R.; Milliken, R.; Richardson, M. I.; Lee, C.

    2013-12-01

    We have explored possible mechanisms for the generation of warm, wet climates on early Mars as a result of greenhouse warming by both water vapor and periodic volcanic trace gas emissions, using the Mars Weather Research and Forecasting (MarsWRF) general circulation model. The presence of both water vapor (a strong greenhouse gas) and other trace greenhouse gases (such as SO2) in a predominantly CO2 atmosphere may act, under certain conditions, to elevate surface temperatures above the freezing point of liquid water, at least episodically. The levels of warming obtained in our simulations do not reach the values seen in Johnson et al., (2008, JGR, 113, E08005), nor are they widespread for extended periods. Rather, warming above 273 K is found in more localized environments and for geologically brief periods of time. Such periodic episodes are controlled by two factors. First is the obliquity of the planet, which plays a significant role is ';activating' extant surface water ice reservoirs, allowing levels of atmospheric water vapor to rise when obliquity is high, and fall precipitously when the obliquity is low. During these low-obliquity periods, the atmosphere is all but incapable of supporting warm surface temperatures except for brief episodes localized wholly in the tropics; thus, there is a natural regulator in the obliquity cycle for maintaining periodic warming. Second is the presence of a secondary trace gas 'trigger', like volcanically released SO2, in the atmosphere. In the absence of such a trace gas, water vapor alone appears incapable of raising temperatures above the melting point; however, by temporarily raising the baseline global temperatures (in the absence of warming by water vapor) by 10-15 K, as with SO2, the trigger gas keeps atmospheric temperatures sufficiently warm, especially during nighttime, to maintain levels of water vapor in the atmosphere that provide the needed warming. Furthermore, we find that global warming can be achieved more

  15. Graphite-moderated and heavy water-moderated spectral shift controlled reactors; Reactores de moderador solido controlados por desplazamiento espectral

    Energy Technology Data Exchange (ETDEWEB)

    Alcala Ruiz, F.

    1984-07-01

    It has been studied the physical mechanisms related with the spectral shift control method and their general positive effects on economical and non-proliferant aspects (extension of the fuel cycle length and low proliferation index). This methods has been extended to non-hydrogenous fuel cells of high moderator/fuel ratio: heavy water cells have been con- trolled by graphite rods graphite-moderated and gas-cooled cells have been controlled by berylium rods and graphite-moderated and water-cooled cells have been controlled by a changing mixture of heavy and light water. It has been carried out neutron and thermal analysis on a pre design of these types of fuel cells. We have studied its neutron optimization and their fuel cycles, temperature coefficients and proliferation indices. Finally, we have carried out a comparative analysis of the fuel cycles of conventionally controlled PWRs and graphite-moderated, water-cooled and spectral shift controlled reactors. (Author) 71 refs.

  16. 1st International Conference on Hydraulic Design in Water Resources Engineering : Channels and Channel Control Structures

    CERN Document Server

    1984-01-01

    The development of water resources has proceeded at an amazing speed around the world in the last few decades. The hydraulic engineer has played his part: in constructing much larger artificial channels than ever before, larger and more sophisticated control structures, and systems of irrigation, drainage and water supply channels in which the flow by its nature is complex and unsteady requiring computer-based techniques at both the design and operation stage. It seemed appropriate to look briefly at some of the developments in hydraulic design resulting from this situation. Hence the idea of the Conference was formed. The Proceedings of the Conference show that hydraulic engineers have been able to acquire a very substantial base of design capability from the experience of the period referred to. The most outstanding development to have occurred is in the combination of physical and mathematical modelling, which in hydraulic engineering has followed a parallel path to that in other branches of engineering sc...

  17. Wettability Control of Gold Surfaces Modified with Benzenethiol Derivatives: Water Contact Angle and Thermal Stability.

    Science.gov (United States)

    Tatara, Shingo; Kuzumoto, Yasutaka; Kitamura, Masatoshi

    2016-04-01

    The water wettability of Au surfaces has been controlled using various benzenethiol derivatives including 4-methylbenzenethiol, pentafluorobenzenethiol, 4-flubrobenzenethiol, 4-methoxy-benzenethiol, 4-nitrobenzenethiol, and 4-hydroxybenzenethiol. The water contact angle of the Au surface modified with the benzenethiol derivative was found to vary in the wide range of 30.9° to 88.3°. The contact angle of the modified Au films annealed was also measured in order to investigate their thermal stability. The change in the contact angle indicated that the modified surface is stable at temperatures below about 400 K. Meanwhile, the activation energy of desorption from the modified surface was estimated from the change in the contact angle. The modified Au surface was also examined using X-ray photoelectron spectroscopy.

  18. Physical controls of hypoxia in waters adjacent to the Yangtze Estuary: A numerical modeling study.

    Science.gov (United States)

    Chen, Xiaofeng; Shen, Zhenyao; Li, Yangyang; Yang, Ye

    2015-08-15

    A three-dimensional circulation model (the Environmental Fluid Dynamic Code) was used to examine the role that physical forcing (river discharge, wind speed and direction) plays in controlling hypoxia in waters adjacent to the Yangtze Estuary. The model assumes that the biological consumption of oxygen is constant in both time and space, which allows the role of physical forcing in modulating the oxygen dynamics to be isolated. Despite of the simplicity of this model, the simulation results showed that it can reproduce the observed variability of dissolved oxygen in waters adjacent to the Yangtze Estuary, thereby highlighting the important role of changes in physical forcing in the variation of hypoxia. The scenarios tested revealed appreciable changes in the areal extent of hypoxia as a function of wind speed and wind direction. Interestingly, well-developed hypoxia was insensitive to river discharge.

  19. Acousto-optic method used to control water pollution by miscible liquids

    Science.gov (United States)

    Ferria, Kouider; Griani, Lazhar; Laouar, Naamane

    2012-05-01

    An acousto-optic (A.O.) method has been developed for controlling the quality of water mixed by miscible liquids like acetone or ethanol… The liquid mixture is filled in a rectangular glass cell, which is placed orthogonally to the incident collimated beam of light. This cell consists of a piezoelectric transducer for generating ultrasonic waves. The collimated light while passing through this cell undergoes a diffraction phenomenon. The diffracted dots are collected by a converging photographic objective and displayed in its back focal plane. The location of the diffracted dots and their intensity are sensitive to any variation of the interaction medium. This result leads to decide about the quality of the water.

  20. Trends in Modelling, Simulation and Design of Water Hydraulic Systems – Motion Control and Open-Ended Solutions

    DEFF Research Database (Denmark)

    Conrad, Finn

    2006-01-01

    The paper presents and discusses a R&D-view on trends in development and best practise in modelling, simulation and design of both low-pressure and high-pressure tap water hydraulic components and systems for motion control as well as open-ended solutions various industrial applications. The focus...... is on the advantages using ordinary tap water and the range of application areas are illustrated with examples, in particular within the food processing industry, humidification operations, water mist systems for fire fighting, high water pressure cleaners, water moisturising systems for wood processing, lumber drying...... is that the components operate with pure water from the tap without additives of any kind. Hence water hydraulics takes the benefit of pure water as fluid being environmentally friendly, easy to clean sanitary design, non-toxic, non-flammable, inexpensive, readily available and easily disposable. The low-pressure tap...

  1. An Intervention with Mineral Water Decreases Cardiometabolic Risk Biomarkers. A Crossover, Randomised, Controlled Trial with Two Mineral Waters in Moderately Hypercholesterolaemic Adults

    Directory of Open Access Journals (Sweden)

    Laura Toxqui

    2016-06-01

    Full Text Available Water intake is essential for health maintenance and disease prevention. The effects of an intervention with two mineral waters, sodium-bicarbonated mineral water (BW or control mineral water low in mineral content (CW, on cardiometabolic risk biomarkers were studied. In a randomised-controlled crossover-trial, sixty-four moderately hypercholesterolaemic adults were randomly assigned to consume 1 L/day of either BW (sodium, 1 g/L; bicarbonate, 2 g/L or CW with the main meals for eight weeks, separated by an eight-week washout period. Blood lipids, lipid oxidation, glucose, insulin, aldosterone, urine pH, urinary electrolytes, blood pressure, body weight, fluid intake, energy, and nutrients from total diet and beverages were determined. Total cholesterol, LDL cholesterol, and glucose decreased (p < 0.01, oxidised LDL tended to decrease (p = 0.073, and apolipoprotein B increased during the intervention, without water type effect. Energy and carbohydrates from beverages decreased since soft drinks and fruit juice consumptions decreased throughout the trial. BW increased urinary pH (p = 0.006 and reduced calcium/creatinine excretion (p = 0.011. Urinary potassium/creatinine decreased with both waters. Consumption of 1 L/day of mineral water with the main meals reduces cardiometabolic risk biomarkers, likely to be attributed to a replacement of soft drinks by water. In addition, BW does not affect blood pressure and exerts a moderate alkalizing effect in the body.

  2. Using inferential sensors for quality control of Everglades Depth Estimation Network water-level data

    Science.gov (United States)

    Petkewich, Matthew D.; Daamen, Ruby C.; Roehl, Edwin A.; Conrads, Paul A.

    2016-09-29

    The Everglades Depth Estimation Network (EDEN), with over 240 real-time gaging stations, provides hydrologic data for freshwater and tidal areas of the Everglades. These data are used to generate daily water-level and water-depth maps of the Everglades that are used to assess biotic responses to hydrologic change resulting from the U.S. Army Corps of Engineers Comprehensive Everglades Restoration Plan. The generation of EDEN daily water-level and water-depth maps is dependent on high quality real-time data from water-level stations. Real-time data are automatically checked for outliers by assigning minimum and maximum thresholds for each station. Small errors in the real-time data, such as gradual drift of malfunctioning pressure transducers, are more difficult to immediately identify with visual inspection of time-series plots and may only be identified during on-site inspections of the stations. Correcting these small errors in the data often is time consuming and water-level data may not be finalized for several months. To provide daily water-level and water-depth maps on a near real-time basis, EDEN needed an automated process to identify errors in water-level data and to provide estimates for missing or erroneous water-level data.The Automated Data Assurance and Management (ADAM) software uses inferential sensor technology often used in industrial applications. Rather than installing a redundant sensor to measure a process, such as an additional water-level station, inferential sensors, or virtual sensors, were developed for each station that make accurate estimates of the process measured by the hard sensor (water-level gaging station). The inferential sensors in the ADAM software are empirical models that use inputs from one or more proximal stations. The advantage of ADAM is that it provides a redundant signal to the sensor in the field without the environmental threats associated with field conditions at stations (flood or hurricane, for example). In the

  3. Diagnosis of processes controlling water vapour in the tropical tropopause layer by a Lagrangian cirrus model

    Directory of Open Access Journals (Sweden)

    C. Ren

    2007-10-01

    Full Text Available We have developed a Lagrangian air-parcel cirrus model (LACM, to diagnose the processes controlling water in the tropical tropopause layer (TTL. LACM applies parameterised microphysics to air parcel trajectories. The parameterisation includes the homogeneous freezing of aerosol droplets, the growth/sublimation of ice particles, and sedimentation of ice particles, so capturing the main dehydration mechanism for air in the TTL. Rehydration is also considered by resetting the water vapour mixing ratio in an air parcel to the value at the point in the 4-D analysis/forecast data used to generate the trajectories, but only when certain conditions, indicative of convection, are satisfied. The conditions act to restrict rehydration of the Lagrangian air parcels to regions where convective transport of water vapour from below is significant, at least to the extent that the analysis/forecast captures this process. The inclusion of hydration and dehydration mechanisms in LACM results in total water fields near tropical convection that have more of the "stripy" character of satellite observations of high cloud, than do either the ECMWF analysis or trajectories without microphysics.

    The mixing ratios of total water in the TTL, measured by a high-altitude aircraft over Brazil (during the TROCCINOX campaign, have been reconstructed by LACM using trajectories generated from ECMWF analysis. Two other Lagrangian reconstructions are also tested: linear interpolation of ECMWF analysed specific humidity onto the aircraft flight track, and instantaneous dehydration to the saturation vapour pressure over ice along trajectories. The reconstructed total water mixing ratios along aircraft flight tracks are compared with observations from the FISH total water hygrometer. Process-oriented analysis shows that modelled cirrus cloud events are responsible for dehydrating the air parcels coming from lower levels, resulting in total water mixing ratios as low as 2

  4. Controls on pH in surface waters of northwestern European shelf seas

    Directory of Open Access Journals (Sweden)

    V. M. C. Rérolle

    2014-01-01

    Full Text Available We present here a high resolution surface water pH dataset obtained in the Northwest European shelf seas in summer 2011. This is the first time that pH has been measured at such a high spatial resolution (10 measurements h–1 in this region. The aim of our paper is to investigate the carbonate chemistry dynamics of the surface water using pH and ancillary data. The main processes controlling the pH distribution along the ship's transect, and their relative importance, were determined using a statistical approach. The study highlights the impact of biological activity, temperature and riverine inputs on the carbonate chemistry dynamics of the shelf seas surface water. For this summer cruise, the biological activity formed the main control of the pH distribution along the cruise transect. Variations in chlorophyll and nutrients explained 29% of the pH variance along the full transect and as much as 68% in the northern part of the transect. In contrast, the temperature distribution explained ca. 50% of the pH variation in the Skagerrak region. Riverine inputs were evidenced by high dissolved organic carbon (DOC levels in the Strait of Moyle (northern Irish Sea and the southern North Sea with consequent remineralisation processes and a reduction in pH. The DOC distribution described 15% of the pH variance along the full transect. This study highlights the high spatial variability of the surface water pH in shelf seawaters where a range of processes simultaneously impacts the carbonate chemistry.

  5. Ice‐water immersion and delayed‐onset muscle soreness: a randomised controlled trial

    Science.gov (United States)

    Sellwood, Kylie Louise; Brukner, Peter; Williams, David; Nicol, Alastair; Hinman, Rana

    2007-01-01

    Objective To determine if ice‐water immersion after eccentric quadriceps exercise minimises the symptoms of delayed‐onset muscle soreness (DOMS). Design A prospective randomised double‐blind controlled trial was undertaken. 40 untrained volunteers performed an eccentric loading protocol with their non‐dominant leg. Interventions Participants were randomised to three 1‐min immersions in either ice water (5±1°C) or tepid water (24°C). Main outcome measures Pain and tenderness (visual analogue scale), swelling (thigh circumference), function (one‐legged hop for distance), maximal isometric strength and serum creatine kinase (CK) recorded at baseline, 24, 48 and 72 h after exercise. Changes in outcome measures over time were compared to determine the effect of group allocation using independent t tests or Mann–Whitney U tests. Results No significant differences were observed between groups with regard to changes in most pain parameters, tenderness, isometric strength, swelling, hop‐for‐distance or serum CK over time. There was a significant difference in pain on sit‐to‐stand at 24 h, with the intervention group demonstrating a greater increase in pain than the control group (median change 8.0 vs 2.0 mm, respectively, p = 0.009). Conclusions The protocol of ice‐water immersion used in this study was ineffectual in minimising markers of DOMS in untrained individuals. This study challenges the wide use of this intervention as a recovery strategy by athletes. PMID:17261562

  6. System Monitoring And Controlling Water Nutrition aquaponics Using Arduino Uno Based Web Server

    Directory of Open Access Journals (Sweden)

    Amanda Fahmi Maarif

    2016-10-01

    Full Text Available Aquaponics is a sustainable farming system that combines aquaculture and hydroponics systems as an integrated system that is symbiotic. In an aquaponics system results from animal excretion contained in this system will be used as natural nutrients hydroponic plants. As for the animals that live on this system will also result in clean water that has been filtered naturally by the plant roots. In the cultivation of an aquaponics system an important factor affecting the development of the ecosystem is the degree of acidity (PH which have a direct impact on the absorption of nutrients in the roots of plants and development of animals that live in this ecosystem. In addition, factors that are not less important is the electroconductivity (EC is the ability to conduct an electric ion in solution to the plant roots. The degree of acidity (pH of water that is normal for an aquaponics ecosystem at 6-7 and value for EC ranged in value of 0.8-1.2 ms / cm. From this study produced a tool that is capable of monitoring in the form of a web server and conduct automatic action in controlling the levels of PH and EC. Based on the results of system testing results obtained sensor Analog PH Meter Kit and Analog Electrical Conductivity Meter capable of monitoring water tank in accordance with the standard measurement tool used is PH meter and EC Solution and the system is also able to control the changes that occur in the water tank in accordance with the standards of PH and EC.

  7. Water turbine control: Historical outline; Zur Entwicklungsgeschichte der Regelung der Wasserturbinen

    Energy Technology Data Exchange (ETDEWEB)

    Fasol, K.H.

    1999-07-01

    Controlled water turbines were first introduced in the second half of the 19th century. The report takes a look at the history of controlled turbines, including those inventions and technologies that paved the way for water turbines as we know them today and for turbine speed control. The report is based on a lecture presented by the author on 10 Nov 1998 in the opening session of the 10th international seminar on hydroelectric power systems at the university of Vienna. The contents are presented in more detail and illustrated by examples. [German] Seit langem widmen sich Wissenschaftshistoriker und auch Ingenieure der Erforschung und Aufarbeitung der Technikgeschichte als eigenstaendige Disziplin der Wissenschaftsgeschichte, wofuer an vielen Universitaeten und Hochschulen entsprechende Lehrstuehle bestehen. Auch an der Entwicklung der Regelungstechnik im Allgemeinen ist das Interesse mit langem erwacht. Die ersten geregelten Wasserturbinen wurden in der zweiten Haelfte des 19. Jahrhunderts bekannt und so ist es denn auch angebracht, die zumindest 130 Jahre der Entwicklungsgeschichte dieser Turbinenregelung darzustellen. Dies ginge nicht, ohne zunaechst auch auf jene anderen Erfindungen und Technologien kurz zurueckzublicken, die Wegbereiter fuer die heutigen Wasserturbinen und fuer die ersten Ansaetze zu deren Drehzahlregelung waren. Diese Arbeit beruht auf einem Hauptvortrag, der am 10 November 1998 in der Eroeffnungssitzung des 10. Internationalen Seminars Wasserkraftanlagen an der Technischen Universitaet Wien gehalten wurde. Gegenueber der schriftlichen Fassung jenes Vortrags wird mit diesem Heft den an diesem speziellen Sektor der Technikgeschichte interessierten Kollegen eine stark erweiterte Fassung vorgelegt. (orig./GL)

  8. Optimization of cycloidal water turbine and the performance improvement by individual blade control

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, In Seong; Lee, Yun Han; Kim, Seung Jo [School of Mechanical and Aerospace Engineering, Seoul National University, San 56-1, Sillim-dong, Gwanak-gu, Seoul, 151-742 (Korea)

    2009-09-15

    This paper investigates an advanced vertical axis turbine to enhance power generation from water energy. The turbine, known as a cycloidal water turbine, is a straight-bladed type adopting a cycloidal blade system that actively controls the rotor blades for improved turbine efficiency, according to the operating conditions. These characteristics enable the turbine to self-start and produce high electric power at a low flow speed, or under complex flow conditions. A parametric study has been carried out by CFD analysis, with various characteristics including different number of blades, chord length variations, variety of tip speed ratios, various hydrofoil shapes, and changing pitch and phase angles. Optimal parameters have been determined, and the performance of the turbine has achieved approximately 70% better performance than that of a fixed pitch turbine. An experimental study has also been carried out which shows that the results correlate quite well with the theoretical predictions although the power output was reduced due to the drag forces of the mechanical devices. Another numerical optimization was carried out to improve the rotor performance by adopting an individual blade control method. Controllable pitch angles were employed to maximize the rotor performance at various operating conditions. The optimized result obtained using genetic algorithm and parallel computing, shows an improvement in performance of around 25% compared with the cycloidal motion. (author)

  9. Biofilm formation and control in a simulated spacecraft water system - Three year results

    Science.gov (United States)

    Schultz, John R.; Flanagan, David T.; Bruce, Rebekah J.; Mudgett, Paul D.; Carr, Sandra E.; Rutz, Jeffrey A.; Huls, M. H.; Sauer, Richard L.; Pierson, Duane L.

    1992-01-01

    Two simulated spacecraft water systems are being used to evaluate the effectiveness of iodine for controlling microbial contamination within such systems. An iodine concentration of about 2.0 mg/L is maintained in one system by passing ultrapure water through an iodinated ion exchange resin. Stainless steel coupons with electropolished and mechanically-polished sides are being used to monitor biofilm formation. Results after three years of operation show a single episode of significant bacterial growth in the iodinated system when the iodine level dropped to 1.9 mg/L. This growth was apparently controlled by replacing the iodinated ion exchange resin, thereby increasing the iodine level. The second batch of resin has remained effective in controlling microbial growth down to an iodine level of 1.0 mg/L. SEM indicates that the iodine has impeded but may have not completely eliminated the formation of biofilm. Metals analyses reveal some corrosion in the iodinated system after 3 years of continuous exposure. Significant microbial contamination has been present continuously in a parallel noniodinated system since the third week of operation.

  10. Training of panellists for the sensory control of bottled natural mineral water in connection with water chemical properties.

    Science.gov (United States)

    Rey-Salgueiro, Ledicia; Gosálbez-García, Aitana; Pérez-Lamela, Concepción; Simal-Gándara, Jesús; Falqué-López, Elena

    2013-11-01

    As bottled mineral water market is increasing in the world (especially in emergent and developed countries), the development of a simple protocol to train a panel to evaluate sensory properties would be a useful tool for natural drinking water industry. A sensory protocol was developed to evaluate bottled natural mineral water (17 still and 10 carbonated trademarks). The tasting questionnaire included 13 attributes for still water plus overall impression and they were sorted by: colour hues, transparency and brightness, odour/aroma and taste/flavour/texture and 2 more for carbonated waters (bubbles and effervescence). The training lasted two months with, at least, 10 sessions, was adequate to evaluate bottled natural mineral water. To confirm the efficiency of the sensory training procedure two sensory groups formed the whole panel. One trained panel (6 persons) and one professional panel (6 sommeliers) and both participated simultaneously in the water tasting evaluation of 3 sample lots. Similar average scores obtained from trained and professional judges, with the same water trademarks, confirmed the usefulness of the training protocol. The differences obtained for trained panel in the first lot confirm the necessity to train always before a sensory procedure. A sensory water wheel is proposed to guide the training in bottled mineral water used for drinking, in connection with their chemical mineral content.

  11. The chronic kidney disease Water Intake Trial (WIT): results from the pilot randomised controlled trial

    Science.gov (United States)

    Clark, William F; Sontrop, Jessica M; Huang, Shih-Han; Gallo, Kerri; Moist, Louise; House, Andrew A; Weir, Matthew A; Garg, Amit X

    2013-01-01

    Background and objectives Increased water intake may benefit kidney function. Prior to initiating a larger randomised controlled trial (RCT), we examined the safety and feasibility of asking adults with chronic kidney disease (CKD) to increase their water intake. Design, setting, participants and measurements Beginning in October 2012, we randomly assigned 29 adults with stage 3 CKD (estimated glomerular filtration rate (eGFR) 30–60 mL/min/1.73 m2 and albuminuria) to one of the two groups of water intake: hydration (n=18) or standard (n=11). We asked the hydration group to increase their water intake by 1.0–1.5 L/day (in addition to usual intake, depending on sex and weight) for 6 weeks, while the control group carried on with their usual intake. Participants collected a 24 h urine sample at baseline and at 2 and 6 weeks after randomisation. Our primary outcome was the between-group difference in change in 24 h urine volume from baseline to 6 weeks. Results (63%)of participants were men, 81% were Caucasians and the average age was 61 years (SD 14 years). The average baseline eGFR was 40 mL/min/1.73 m2 (SD 11 mL/min/1.73 m2); the median albumin to creatinine ratio was 19 mg/mmol (IQR 6–74 mg/mmol). Between baseline and 6-week follow-up, the hydration group's average 24 h urine volume increased by 0.7 L/day (from 2.3 to 3.0 L/day) and the control group's 24 h urine decreased by 0.3 L/day (from 2.0 to 1.7 L/day; between-group difference in change: 0.9 L/day (95% CI 0.4 to 1.5; p=0.002)). We found no significant changes in urine, serum osmolality or electrolyte concentrations, or eGFR. No serious adverse events or changes in quality of life were reported. Conclusions A pilot RCT indicates adults with stage 3 CKD can successfully and safely increase water intake by up to 0.7 L/day in addition to usual fluid intake. Trial registration Registered with Clinical Trials—government identifier NCT01753466. PMID:24362012

  12. Heat dissipation in controlled environment enclosures through the application of water screens

    Science.gov (United States)

    Warrington, I. J.; Halligan, E. A.; Ruby, L. C.; Mcnaughton, K. G.

    1994-01-01

    The use of plate glass-water thermal barriers in controlled environment facilities effectively reduces the thermal load within the plant growth chamber. This allows high PPFs to be provided for plant growth and development studies, adequate simulation of daily light integrals, and simulation of peak PPF's. Further, substantial amounts of incandescent lamp supplementation can be used to achieve simulation of daylight R:FR ratios which are needed to ensure adequate stem development in some species. While the focus in this paper is on the use of entire thermal barriers which separate the lighting enclosure from the plant growth chamber, the same principles apply to the use of water jackets for cooling individual lamps (such as can occur with xenon-arc lamps). In this instance, the barrier separating the lamps from the plant chamber can be much simpler (e.g., plexiglass) as the main function of the barrier is to separate the air ventilation of the lamp enclosure from the air system within the plant growth chamber. The main advantage of water as a thermal barrier is the negligible absorption of radiation in the photosynthetically-active and near infrared wavebands. Consequently, plate glass-water barriers typically allow transmission of approximately 90% of radiation in these regions. While ventilated double and triple glazing systems appear to be attractive alternative to water barriers from an operating standpoint, their significant absorption in the biologically-important wavebands (7 - 12%) with each glass layer and longer-wave cut-offs (typically 2500 - 4000 nm) makes them a much less attractive alternative. The data presented here demonstrate clearly that measurement of PPF alone is not an adequate representation of the radiation environment being used in a controlled environment study. The amounts and proportions of long-wave and short-wave radiation in a plant growth chamber are dependent on lamp type, lamp combination, presence of a thermal barrier, the type of

  13. Light Water Reactor Sustainability Program A Reference Plan for Control Room Modernization: Planning and Analysis Phase

    Energy Technology Data Exchange (ETDEWEB)

    Jacques Hugo; Ronald Boring; Lew Hanes; Kenneth Thomas

    2013-09-01

    The U.S. Department of Energy’s Light Water Reactor Sustainability (LWRS) program is collaborating with a U.S. nuclear utility to bring about a systematic fleet-wide control room modernization. To facilitate this upgrade, a new distributed control system (DCS) is being introduced into the control rooms of these plants. The DCS will upgrade the legacy plant process computer and emergency response facility information system. In addition, the DCS will replace an existing analog turbine control system with a display-based system. With technology upgrades comes the opportunity to improve the overall human-system interaction between the operators and the control room. To optimize operator performance, the LWRS Control Room Modernization research team followed a human-centered approach published by the U.S. Nuclear Regulatory Commission. NUREG-0711, Rev. 3, Human Factors Engineering Program Review Model (O’Hara et al., 2012), prescribes four phases for human factors engineering. This report provides examples of the first phase, Planning and Analysis. The three elements of Planning and Analysis in NUREG-0711 that are most crucial to initiating control room upgrades are: • Operating Experience Review: Identifies opportunities for improvement in the existing system and provides lessons learned from implemented systems. • Function Analysis and Allocation: Identifies which functions at the plant may be optimally handled by the DCS vs. the operators. • Task Analysis: Identifies how tasks might be optimized for the operators. Each of these elements is covered in a separate chapter. Examples are drawn from workshops with reactor operators that were conducted at the LWRS Human System Simulation Laboratory HSSL and at the respective plants. The findings in this report represent generalized accounts of more detailed proprietary reports produced for the utility for each plant. The goal of this LWRS report is to disseminate the technique and provide examples sufficient to

  14. Plasmon-Enhanced Photoelectrochemical Water Splitting with Size-Controllable Gold Nanodot Arrays

    Energy Technology Data Exchange (ETDEWEB)

    Kim, HJ; Lee, SH; Upadhye, AA; Ro, I; Tejedor-Tejedor, MI; Anderson, MA; Kim, WB; Huber, GW

    2014-10-01

    Size-controllable Au nanodot arrays (50, 63, and 83 nm dot size) with a narrow size distribution (+/- 5%) were prepared by a direct contact printing method on an indium tin oxide (ITO) substrate. Titania was added to the Au nanodots using TiO2 sols of 2-3 nm in size. This created a precisely controlled Au nanodot with 110 nm of TiO2 overcoats. Using these precisely controlled nanodot arrays, the effects of Au nanodot size and TiO2 overcoats were investigated for photoelectrochemical water splitting using a three-electrode system with a fiber-optic visible light source. From UV-vis measurement, the localized surface plasmon resonance (LSPR) peak energy (ELSPR) increased and the LSPR line width (G) decreased with decreasing Au nanodot size. The generated plasmonic enhancement for the photoelectrochemical water splitting reaction increased with decreasing Au particle size. The measured plasmonic enhancement for light on/off experiments was 25 times for the 50 nm Au size and 10 times for the 83 nm Au nanodot size. The activity of each catalyst increased by a factor of 6 when TiO2 was added to the Au nanodots for all the samples. The activity of the catalyst was proportional to the quality factor (defined as Q = E-LSPR/Gamma) of the plasmonic metal nanostructure. The enhanced water splitting performance with the decreased Au nanodot size is probably due to more generated charge carriers (electron/hole pair) by local field enhancement as the quality factor increases.

  15. Control Effect of 80%Nicosulfuron·Atrazine Water-dispersible Granules on Weeds in Spring Maize Field

    Institute of Scientific and Technical Information of China (English)

    Yueqi SHEN; Rende Ql

    2014-01-01

    This study aimed to investigate the control effect of different concentrations of 80% nicosulfuron·atrazine water-dispersible granules on weeds in spring maize field. [Method] Maize field was sprayed with 300, 375, 450, 750 g/hm2 80% nicosulfuron·atrazine water-dispersible granules respectively, with 40 g/L nico-sulfuron suspending concentrate and 38% atrazine suspending concentrate as con-trol agents. Artificial weeding and control (CK) plots were set. [Result] Fresh weight control efficiency of 375-750 g/hm2 80% nicosulfuron ·atrazine water-dispersible granules was significantly higher than that of 40 g/L nicosulfuron suspending con-centrate and 38% atrazine suspending concentrate; no obvious phytotoxicity symp-toms were observed after application of 300-450 g/hm2 80% nicosulfuron·atrazine water-dispersible granules; 750 g/hm2 80% nicosulfuron·atrazine water-dispersible granules posed certain impact on the growth of maize seedlings. Compared with control plots, various doses of 80% nicosulfuron·atrazine water-dispersible granules signifi-cantly improved the yield of maize. [Conclusion] ln the present study, 375-450 g/hm2 80% nicosulfuron·atrazine water-dispersible granules exhibited high control effect on weeds in maize field and were safe for the growth of maize seedlings.

  16. Control of erosion and water pollution during exploitation of the Meirama lignites. Control de la erosion y contaminacion de las aguas en la explotacion de lignitos de Meirama

    Energy Technology Data Exchange (ETDEWEB)

    Lopez Jimeno, E. (Lignitos de Meirama, S.A. (Spain))

    1989-01-01

    The required reclamation of land disturbed by surface coal mining often results in the creation of some slopes and soils that are prone to rapid erosion and sediment production. The are two general methods of preventing or controlling soil erosion from rainfall and water running. These two methods are the building of mechanical structures and covering the soil with live vegetation. This paper discusses the water control methods, the design of the drainage and acid water treatment plant of Lignitos de Meirama. 5 refs., 10 figs.

  17. Economic Model Predictive Control for Hot Water Based Heating Systems in Smart Buildings

    DEFF Research Database (Denmark)

    Awadelrahman, M. A. Ahmed; Zong, Yi; Li, Hongwei

    2017-01-01

    This paper presents a study to optimize the heating energy costs in a residential building with varying electricity price signals based on an Economic Model Predictive Controller (EMPC). The investigated heating system consists of an air source heat pump (ASHP) incorporated with a hot water tank...... as active Thermal Energy Storage (TES), where two optimization problems are integrated together to optimize both the ASHP electricity consumption and the building heating consumption utilizing a heat dynamic model of the building. The results show that the proposed EMPC can save the energy cost by load...

  18. Monitoring protozoa in water destined for human consumption; Control de protozoos en aguas de consumo humano

    Energy Technology Data Exchange (ETDEWEB)

    Miralles, F.; Moreno, C.; Apraiz, D.; Catalan, V. [LABAQUA, Alicante (Spain)

    1995-12-31

    It has been demonstrated that the protozoa Giardia and Cryptosporidium are agents that cause the appearance of epidemic outbreaks of gastro enteritis of variable gravity. Because of their resistance to traditional water treatment processes it is important to control them periodically, for which microscopic techniques, subjective and of low sensitivity, are generally used. Nevertheless, and thanks to the molecular biology development, the new and powerful techniques based on the amplification of the DNA by the polymerase chain reaction (PCR) have started to take the place of the traditional methods. (Author) 54 refs.

  19. Beneficial effect of sulphate-bicarbonate-calcium water on gallstone risk and weight control

    Institute of Scientific and Technical Information of China (English)

    Stefano Ginanni Corradini; Edoardo Poli; Adriano De Santis; Aldo Roda; Carolina Colliva; Patrizia Simoni; Adolfo Francesco Attili; Flaminia Ferri; Michela Mordenti; Luigi Iuliano; Maria Siciliano; Maria Antonella Burza; Bruno Sordi; Barbara Caciotti; Maria Pacini

    2012-01-01

    AIM:To investigate the effect of drinking sulphate-bicarbonate-calcium thermal water (TW) on risk factors for atherosclerosis and cholesterol gallstone disease.METHODS:Postmenopausal women with functional dyspepsia and/or constipation underwent a 12 d cycle of thermal (n =20) or tap (n =20) water controlled drinking.Gallbladder fasting volume at ultrasound,blood vitamin E,oxysterols (7-β-hydroxycholesterol.and 7-ketocholesterol),bile acid (BA),triglycerides,total/low density lipoprotein and high density lipoprotein cholesterol were measured at baseline and at the end of the study.Food consumption,stool frequency and body weight were recorded daily.RESULTS:Blood lipids,oxysterols and vitamin E were not affected by either thermal or tap water consumption.Fasting gallbladder volume was significantly (P <0.005) smaller at the end of the study than at baseline in the TW (15.7 ± 1.1 mL vs 20.1 ± 1.7 mL) but not in the tap water group (19.0 ± 1.4 mL vs 19.4 ± 1.5 mL).Total serum BA concentration was significantly (P <0.05) higher at the end of the study than at baseline in the TW (5.83-1.24 μmol vs 4.25 ± 1.00 μmol) but not in the tap water group (3.41 ± 0.46 μmol vs 2.91 ± 0.56 μmol).The increased BA concentration after TW consumption was mainly accounted for by glycochenodeoxycholic acid.The number of pasta (P < 0.001),meat (P < 0.001) and vegetable (P < 0.005) portions consumed during the study and of bowel movements per day (P < 0.05) were significantly higher in the TW than in the tap water group.Body weight did not change at the end of the study as compared to baseline in both groups.CONCLUSION:Sulphate-bicarbonate-calcium water consumption has a positive effect on lithogenic risk and intestinal transit and allows maintenance of a stable body weight despite a high food intake.

  20. Beneficial effect of sulphate-bicarbonate-calcium water on gallstone risk and weight control

    Science.gov (United States)

    Corradini, Stefano Ginanni; Ferri, Flaminia; Mordenti, Michela; Iuliano, Luigi; Siciliano, Maria; Burza, Maria Antonella; Sordi, Bruno; Caciotti, Barbara; Pacini, Maria; Poli, Edoardo; Santis, Adriano De; Roda, Aldo; Colliva, Carolina; Simoni, Patrizia; Attili, Adolfo Francesco

    2012-01-01

    AIM: To investigate the effect of drinking sulphate-bicarbonate-calcium thermal water (TW) on risk factors for atherosclerosis and cholesterol gallstone disease. METHODS: Postmenopausal women with functional dyspepsia and/or constipation underwent a 12 d cycle of thermal (n = 20) or tap (n = 20) water controlled drinking. Gallbladder fasting volume at ultrasound, blood vitamin E, oxysterols (7-β-hydroxycholesterol and 7-ketocholesterol), bile acid (BA), triglycerides, total/low density lipoprotein and high density lipoprotein cholesterol were measured at baseline and at the end of the study. Food consumption, stool frequency and body weight were recorded daily. RESULTS: Blood lipids, oxysterols and vitamin E were not affected by either thermal or tap water consumption. Fasting gallbladder volume was significantly (P < 0.005) smaller at the end of the study than at baseline in the TW (15.7 ± 1.1 mL vs 20.1 ± 1.7 mL) but not in the tap water group (19.0 ± 1.4 mL vs 19.4 ± 1.5 mL). Total serum BA concentration was significantly (P < 0.05) higher at the end of the study than at baseline in the TW (5.83 ± 1.24 μmol vs 4.25 ± 1.00 μmol) but not in the tap water group (3.41 ± 0.46 μmol vs 2.91 ± 0.56 μmol). The increased BA concentration after TW consumption was mainly accounted for by glycochenodeoxycholic acid. The number of pasta (P < 0.001), meat (P < 0.001) and vegetable (P < 0.005) portions consumed during the study and of bowel movements per day (P < 0.05) were significantly higher in the TW than in the tap water group. Body weight did not change at the end of the study as compared to baseline in both groups. CONCLUSION: Sulphate-bicarbonate-calcium water consumption has a positive effect on lithogenic risk and intestinal transit and allows maintenance of a stable body weight despite a high food intake. PMID:22408352

  1. Water

    CSIR Research Space (South Africa)

    Van Wyk, Llewellyn V

    2010-08-01

    Full Text Available Water scarcity is without a doubt on of the greatest threats to the human species and has all the potential to destabilise world peace. Falling water tables are a new phenomenon. Up until the development of steam and electric motors, deep groudwater...

  2. A Water Hammer Protection Method for Mine Drainage System Based on Velocity Adjustment of Hydraulic Control Valve

    Directory of Open Access Journals (Sweden)

    Yanfei Kou

    2016-01-01

    Full Text Available Water hammer analysis is a fundamental work of pipeline systems design process for water distribution networks. The main characteristics for mine drainage system are the limited space and high cost of equipment and pipeline changing. In order to solve the protection problem of valve-closing water hammer for mine drainage system, a water hammer protection method for mine drainage system based on velocity adjustment of HCV (Hydraulic Control Valve is proposed in this paper. The mathematic model of water hammer fluctuations is established based on the characteristic line method. Then, boundary conditions of water hammer controlling for mine drainage system are determined and its simplex model is established. The optimization adjustment strategy is solved from the mathematic model of multistage valve-closing. Taking a mine drainage system as an example, compared results between simulations and experiments show that the proposed method and the optimized valve-closing strategy are effective.

  3. Understanding, Monitoring, and Controlling Biofilm Growth in Drinking Water Distribution Systems.

    Science.gov (United States)

    Liu, Sanly; Gunawan, Cindy; Barraud, Nicolas; Rice, Scott A; Harry, Elizabeth J; Amal, Rose

    2016-09-06

    In drinking water distribution systems (DWDS), biofilms are the predominant mode of microbial growth, with the presence of extracellular polymeric substance (EPS) protecting the biomass from environmental and shear stresses. Biofilm formation poses a significant problem to the drinking water industry as a potential source of bacterial contamination, including pathogens, and, in many cases, also affecting the taste and odor of drinking water and promoting the corrosion of pipes. This article critically reviews important research findings on biofilm growth in DWDS, examining the factors affecting their formation and characteristics as well as the various technologies to characterize and monitor and, ultimately, to control their growth. Research indicates that temperature fluctuations potentially affect not only the initial bacteria-to-surface attachment but also the growth rates of biofilms. For the latter, the effect is unique for each type of biofilm-forming bacteria; ammonia-oxidizing bacteria, for example, grow more-developed biofilms at a typical summer temperature of 22 °C compared to 12 °C in fall, and the opposite occurs for the pathogenic Vibrio cholerae. Recent investigations have found the formation of thinner yet denser biofilms under high and turbulent flow regimes of drinking water, in comparison to the more porous and loosely attached biofilms at low flow rates. Furthermore, in addition to the rather well-known tendency of significant biofilm growth on corrosion-prone metal pipes, research efforts also found leaching of growth-promoting organic compounds from the increasingly popular use of polymer-based pipes. Knowledge of the unique microbial members of drinking water biofilms and, importantly, the influence of water characteristics and operational conditions on their growth can be applied to optimize various operational parameters to minimize biofilm accumulation. More-detailed characterizations of the biofilm population size and structure are now

  4. Water Use Practices Limit the Effectiveness of a Temephos-Based Aedes aegypti Larval Control Program in Northern Argentina

    Science.gov (United States)

    Garelli, Fernando M.; Espinosa, Manuel O.; Weinberg, Diego; Trinelli, María A.; Gürtler, Ricardo E.

    2011-01-01

    Background A five-year citywide control program based on regular application of temephos significantly reduced Aedes aegypti larval indices but failed to maintain them below target levels in Clorinda, northern Argentina. Incomplete surveillance coverage and reduced residuality of temephos were held as the main putative causes limiting effectiveness of control actions. Methodology The duration of temephos residual effects in household-owned water-holding tanks (the most productive container type and main target for control) was estimated prospectively in two trials. Temephos was applied using spoons or inside perforated small zip-lock bags. Water samples from the study tanks (including positive and negative controls) were collected weekly and subjected to larval mortality bioassays. Water turnover was estimated quantitatively by adding sodium chloride to the study tanks and measuring its dilution 48 hs later. Principal Findings The median duration of residual effects of temephos applied using spoons (2.4 weeks) was significantly lower than with zip-lock bags (3.4 weeks), and widely heterogeneous between tanks. Generalized estimating equations models showed that bioassay larval mortality was strongly affected by water type and type of temephos application depending on water type. Water type and water turnover were highly significantly associated. Tanks filled with piped water had high turnover rates and short-lasting residual effects, whereas tanks filled with rain water showed the opposite pattern. On average, larval infestations reappeared nine weeks post-treatment and seven weeks after estimated loss of residuality. Conclusions Temephos residuality in the field was much shorter and more variable than expected. The main factor limiting temephos residuality was fast water turnover, caused by householders' practice of refilling tanks overnight to counteract the intermittence of the local water supply. Limited field residuality of temephos accounts in part for the

  5. 基于PLC控制的水塔供水系统设计%Water Supply System Design of Water Tower Based on PLC Control

    Institute of Scientific and Technical Information of China (English)

    刘杰

    2014-01-01

    This article compared the traditional control method of automatic water system, designed the electrical control system based on PLC control which has the advantages of high reliability, strong anti-interference ability, convenient programming, ease of use, etc., developed the scheme of using the programmable controller to control the water supply system of water tower, completed the hardware and software design of electrical control system, including PLC model selection, assignment of I/O ports, I/O hardware wiring diagram drawing, PLC ladder program design. This article also elaborated the water supply process of water tower based on PLC control, and gave the corresponding control schematic.%文章在对比了传统的自动供水系统的控制方法,设计了基于PLC控制的电气控制系统,具有可靠性高,抗干扰能力强,编程方便,易于使用等优点,制定了采用可编程控制器控制水塔供水系统的方案,完成了电气控制系统硬件和软件的设计,其中包括PLC机型的选择、I/O端口的分配、I/O硬件接线图的绘制、PLC梯形图程序的设计。文章对PLC控制水塔供水工作过程也作了详细阐述,并给出了相应的控制原理图。

  6. Sustainable Improvement of Urban River Network Water Quality and Flood Control Capacity by a Hydrodynamic Control Approach-Case Study of Changshu City

    Science.gov (United States)

    Xie, Chen; Yang, Fan; Liu, Guoqing; Liu, Yang; Wang, Long; Fan, Ziwu

    2017-01-01

    Water environment of urban rivers suffers degradation with the impacts of urban expansion, especially in Yangtze River Delta. The water area in cites decreased sharply, and some rivers were cut off because of estate development, which brings the problems of urban flooding, flow stagnation and water deterioration. The approach aims to enhance flood control capability and improve the urban river water quality by planning gate-pump stations surrounding the cities and optimizing the locations and functions of the pumps, sluice gates, weirs in the urban river network. These gate-pump stations together with the sluice gates and weirs guarantee the ability to control the water level in the rivers and creating hydraulic gradient artificially according to mathematical model. Therefore the flow velocity increases, which increases the rate of water exchange, the DO concentration and water body self-purification ability. By site survey and prototype measurement, the river problems are evaluated and basic data are collected. The hydrodynamic model of the river network is established and calibrated to simulate the scenarios. The schemes of water quality improvement, including optimizing layout of the water distribution projects, improvement of the flow discharge in the river network and planning the drainage capacity are decided by comprehensive Analysis. Finally the paper introduces the case study of the approach in Changshu City, where the approach is successfully implemented.

  7. Selection, efficacy, ecological characterization and formulation of fungal control agents against water hyacinth [Eichhornia crassipes (Martius) Solms] in Mali

    OpenAIRE

    Dagno, Karim

    2011-01-01

    Rice and irrigated orchards are considered as the most important food and economical sources in Mali, which watered from Niger River. However, stable productions of rice and orchards products have been limited by many disease, insects, and weeds. Recently, water hyacinth infestation in river of Niger has increased drastically and as affected by the decrease of water flow due to clogging dams and irrigation work. Biological control of weeds is an alternative approach to chemical herbicide use,...

  8. Operations GUNNERSIDE and GROUSE - Special Operations During World War II Against the German Controlled Heavy Water Plant in Norway

    Science.gov (United States)

    2010-04-07

    Vemork be attacked with sufficient force to destroy all accumulated stocks of heavy water , the major pieces of machinery in the electrolysis plant...chain reaction within the nuclear reactor . Jens-Anton Poulsson, The Heavy Water Raid: The Race for the Atom Bomb 1942-1944 (Orion Forlag AS, 2009...Special Operations during N/A World War ll against the German Controlled Heavy Water Plant in NoiWay. 5b. GRANT NUMBER N/A 5c. PROGRAM ELEMENT NUMBER

  9. Green rust formation controls nutrient availability in a ferruginous water column

    DEFF Research Database (Denmark)

    Zegeye, Asfaw; Bonneville, Steeve; Benning, Liane G.

    2013-01-01

    Iron-rich (ferruginous) conditions were a prevalent feature of the ocean throughout much of Earth's history. The nature of elemental cycling in such settings is poorly understood, however, thus hampering reconstruction of paleoenvironmental conditions during key periods in Earth evolution...... a mechanism for reconstructing ancient ocean chemistry. Such reconstructions depend, however, on precise knowledge of the iron minerals formed in the water column. Here, we combine mineralogical and geochemical analyses to demonstrate formation of the mixed-valence iron mineral, green rust, in ferruginous....... This is particularly true regarding controls on nutrient bioavailability, which is intimately linked to Earth's oxygenation history. Elemental scavenging during precipitation of iron minerals exerts a major control on nutrient cycling in ferruginous basins, and the predictable nature of removal processes provides...

  10. Wave Synchronizing Crane Control during Water Entry in Offshore Moonpool Operations - Experimental Results

    Directory of Open Access Journals (Sweden)

    Tor A. Johansen

    2004-01-01

    Full Text Available A new strategy for active control in heavy-lift offshore crane operations is suggested, by introducing a new concept referred to as wave synchronization. Wave synchronization reduces the hydrodynamic forces by minimization of variations in the relative vertical velocity between payload and water using a wave amplitude measurement. Wave synchronization is combined with conventional active heave compensation to obtain accurate control. Experimental results using a scale model of a semi-submerged vessel with a moonpool shows that wave synchronization leads to significant improvements in performance. Depending on the sea state and payload, the results indicate that the reduction in the standard deviation of the wire tension may be up to 50

  11. Control of degreening in postharvest green sour citrus fruit by electrostatic atomized water particles.

    Science.gov (United States)

    Yamauchi, Naoki; Takamura, Kohtaro; Shigyo, Masayoshi; Migita, Catharina Taiko; Masuda, Yukihiro; Maekawa, Tetsuya

    2014-08-01

    The effect of electrostatic atomized water particles (EAWP) on degreening of green sour citrus fruit during storage was determined. Superoxide anion and hydroxyl radicals included in EAWP were present on the surface of the fruit peel after the treatment. Hydrogen peroxide was formed from EAWP in an aqueous solution, which could indicate that a hydroxyl radical of EAWP turns to hydrogen peroxide in the fruit flavedo as well as in the aqueous solution. EAWP treatment effectively suppressed the degreening of green yuzu and Nagato-yuzukichi fruits during storage at 20°C. The enhancement in K+ ion leakage of both EAWP-treated fruits reduced in comparison with the control. In spite of EAWP treatment, total peroxide level in both fruits showed almost no changes during storage, suggesting that hydrogen peroxide formed by EAWP treatment could stimulate the activation of hydrogen peroxide scavenging system and control degreening of these fruits during storage.

  12. Controlled synthesis of titania using water-soluble titanium complexes: A review

    Science.gov (United States)

    Truong, Quang Duc; Dien, Luong Xuan; Vo, Dai-Viet N.; Le, Thanh Son

    2017-07-01

    The development of human society has led to the increase in energy and resources consumption as well as the arising problems of environmental damage and the toxicity to the human health. The development of novel synthesis method which tolerates utilization of toxic solvents and chemicals would fulfill the demand of the society for safer, softer, and environmental friendly technologies. For the past decades, a remarkable progress has been attained in the development of new water-soluble titanium complexes (WSTC) and their use for the synthesis of nanocrystalline titanium dioxide materials by aqueous solution-based approaches. The progress of synthesis of nanocrystalline titanium dioxide using such WSTCs is reviewed in this work. The key structural features responsible for the successfully controlled synthesis of TiO2 are discussed to provide guidelines for the morphology-controlled synthesis. Finally, this review ends with a summary and some perspectives on the challenges as well as new directions in this fascinating research.

  13. The control of Simuliidae (Diptera, Nematocera) in South African rivers by modification of the water flow volume.

    Science.gov (United States)

    Howell, C J; Begemann, G J; Muir, R W; Louw, P

    1981-03-01

    It was found that the build-up of simuliid numbers subsequent to the construction of dams in the Vaal and Orange Rivers could be successfully prevented by periodic, artificially controlled reductions in the water-levels in these rivers.

  14. Report: State of Washington Water Pollution Control State Revolving Fund Financial Statements with Independent Auditor's Report, June 30, 2003

    Science.gov (United States)

    Report #2004-1-00067, May 26, 2004. The financial statements referred to in the first paragraph present fairly the financial position of the Washington Department of Ecology Water Pollution Control State Revolving Fund as of June 30, 2003.

  15. Microbiological quality and quality control of purified water and ultrapure dialysis fluids for online hemodiafiltration in routine clinical practice.

    NARCIS (Netherlands)

    Penne, E.L.; Visser, L.; Dorpel, M.A. van den; Weerd, N.C. van der; Mazairac, A.H.; Jaarsveld, B.C. van; Koopman, M.G.; Vos, P.; Feith, G.W.; Kremer Hovinga, T.K.; Hamersvelt, H.W. van; Wauters, I.M.; Bots, M.L.; Nube, M.J.; Wee, P.M. ter; Blankestijn, P.J.; Grooteman, M.P.C.

    2009-01-01

    During online hemodiafiltration, patients are directly infused with sterile substitution solutions to maintain fluid balance. Adequate water treatment and a well-organized quality control process are essential to provide non-pyrogenic fluids with consistent optimal quality. We sought to assess water

  16. Microbiological quality and quality control of purified water and ultrapure dialysis fluids for online hemodiafiltration in routine clinical practice

    NARCIS (Netherlands)

    Penne, E. Lars; Visser, Linda; van den Dorpel, Marinus A.; van der Weerd, Neelke C.; Mazairac, Albert H. A.; van Jaarsveld, Brigit C.; Koopman, Marion G.; Vos, Pieter; Feith, Geert W.; Kremer Hovinga, T; van Hamersvelt, Henk W.; Wauters, Inge M.; Bots, Michiel L.; Nube, Menso J.; ter Wee, Piet M.; Blankestijn, Peter J.; Grooteman, Muriel P. C.

    2009-01-01

    During online hemodiafiltration, patients are directly infused with sterile substitution solutions to maintain fluid balance. Adequate water treatment and a well-organized quality control process are essential to provide non-pyrogenic fluids with consistent optimal quality. We sought to assess water

  17. Pilot-scale cooling tower to evaluate corrosion, scaling, and biofouling control strategies for cooling system makeup water.

    Science.gov (United States)

    Chien, S H; Hsieh, M K; Li, H; Monnell, J; Dzombak, D; Vidic, R

    2012-02-01

    Pilot-scale cooling towers can be used to evaluate corrosion, scaling, and biofouling control strategies when using particular cooling system makeup water and particular operating conditions. To study the potential for using a number of different impaired waters as makeup water, a pilot-scale system capable of generating 27,000 kJ∕h heat load and maintaining recirculating water flow with a Reynolds number of 1.92 × 10(4) was designed to study these critical processes under conditions that are similar to full-scale systems. The pilot-scale cooling tower was equipped with an automatic makeup water control system, automatic blowdown control system, semi-automatic biocide feeding system, and corrosion, scaling, and biofouling monitoring systems. Observed operational data revealed that the major operating parameters, including temperature change (6.6 °C), cycles of concentration (N = 4.6), water flow velocity (0.66 m∕s), and air mass velocity (3660 kg∕h m(2)), were controlled quite well for an extended period of time (up to 2 months). Overall, the performance of the pilot-scale cooling towers using treated municipal wastewater was shown to be suitable to study critical processes (corrosion, scaling, biofouling) and evaluate cooling water management strategies for makeup waters of complex quality.

  18. A novel eco-friendly technique for efficient control of lime water softening process.

    Science.gov (United States)

    Ostovar, Mohamad; Amiri, Mohamad

    2013-12-01

    Lime softening is an established type of water treatment used for water softening. The performance of this process is highly dependent on lime dosage. Currently, lime dosage is adjusted manually based on chemical tests, aimed at maintaining the phenolphthalein (P) and total (M) alkalinities within a certain range (2 P - M > or = 5). In this paper, a critical study of the softening process has been presented. It has been shown that the current method is frequently incorrect. Furthermore, electrical conductivity (EC) has been introduced as a novel indicator for effectively characterizing the lime softening process.This novel technique has several advantages over the current alkalinities method. Because no chemical reagents are needed for titration, which is a simple test, there is a considerable reduction in test costs. Additionally, there is a reduction in the treated water hardness and generated sludge during the lime softening process. Therefore, it is highly eco-friendly, and is a very cost effective alternative technique for efficient control of the lime softening process.

  19. Rapid and controlled transformation of nitrate in water and brine by stabilized iron nanoparticles

    Science.gov (United States)

    Xiong, Zhong; Zhao, Dongye; Pan, Gang

    2009-05-01

    Highly reactive zero-valent iron (ZVI) nanoparticles stabilized with carboxymethyl cellulose (CMC) were tested for reduction of nitrate in fresh water and brine. Batch kinetic tests showed that the pseudo first-order rate constant ( k obs) with the stabilized nanoparticles was five times greater than that for non-stabilized counterparts. The stabilizer not only increased the specific surface area of the nanoparticles, but also increased the reactive particle surface. The allocation between the two reduction products, NH4 + and N2, can be manipulated by varying the ZVI-to-nitrate molar ratio and/or applying a Cu-Pd bimetallic catalyst. Greater CMC-to-ZVI ratios lead to faster nitrate reduction. Application of a 0.05 M HEPES buffer increased the k obs value by 15 times compared to that without pH control. Although the presence of 6% NaCl decreased k obs by 30%, 100% nitrate was transformed within 2 h in the saline water. The technology provides a powerful alternative for treating water with concentrated nitrate such as ion exchange brine.

  20. Controllable Edge Oxidation and Bubbling Exfoliation Enable the Fabrication of High Quality Water Dispersible Graphene

    Science.gov (United States)

    Tian, Suyun; Sun, Jing; Yang, Siwei; He, Peng; Wang, Gang; di, Zengfeng; Ding, Guqiao; Xie, Xiaoming; Jiang, Mianheng

    2016-09-01

    Despite significant progresses made on mass production of chemically exfoliated graphene, the quality, cost and environmental friendliness remain major challenges for its market penetration. Here, we present a fast and green exfoliation strategy for large scale production of high quality water dispersible few layer graphene through a controllable edge oxidation and localized gas bubbling process. Mild edge oxidation guarantees that the pristine sp2 lattice is largely intact and the edges are functionalized with hydrophilic groups, giving rise to high conductivity and good water dispersibility at the same time. The aqueous concentration can be as high as 5.0 mg mL‑1, which is an order of magnitude higher than previously reports. The water soluble graphene can be directly spray-coated on various substrates, and the back-gated field effect transistor give hole and electron mobility of ~496 and ~676 cm2 V‑1 s‑1, respectively. These results achieved are expected to expedite various applications of graphene.