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Water Transfer (water + transfer)

Distribution by Scientific Domains

Engineering	50%
Humanities and Social Sciences	20%

Selected Abstracts

Ground Water Transfer Initiates Complete Reductive Dechlorination in a PCE-Contaminated Aquifer

GROUND WATER MONITORING & REMEDIATION, Issue 3 2007
R. Lookman
We conducted a field test to investigate whether ground water transfer from one site (showing complete natural reductive dechlorination of chlorinated ethenes to ethene) could induce full reductive dechlorination at another site polluted with tetrachloroethene and its partial dechlorination products trichloroethene and cis -dichloroethene (cDCE). Addition of electron donor (lactate) at the test site established low redox conditions but did not stimulate further dechlorination past cDCE. After transferring 2 m3 of ground water from the first site to the test site, full dechlorination commenced and high levels of ethene were measured to distances up to 6 m downstream of the injection location within 7 months. Ground water samples from monitoring wells were analyzed before and after inoculation of the test site for the presence of Dehalococcoides species (16S ribosomal RNA) and vinyl chloride reductase (vCRA) genes using the polymerase chain reaction. These tests showed that Dehalococcoides species were present both before and after ground water transfer, while vCRA genes were detected at the test site only after ground water transfer. The vCRA genes were detected in ground water samples collected 6 m downstream of the injection locations 7 months after ground water transfer, suggesting that the microorganisms carrying the dehalogenase genes were effectively transported in the aquifer. [source]

Owens Valley Revisited: A Reassessment of the West's First Great Water Transfer by Gary D. Libecap

JOURNAL OF REGIONAL SCIENCE, Issue 2 2010
Eric Schuck
No abstract is available for this article. [source]

Periodic Mesoporous Organosilicas: A Type of Hybrid Support for Water-Mediated Reactions

CHEMISTRY - AN ASIAN JOURNAL, Issue 7 2007
Ying Wan Prof.
Abstract Hybrid mesoporous periodic organosilicas (Ph-PMOs) with phenylene moieties embedded inside the silica matrix were used as a heterogeneous catalyst for the Ullmann coupling reaction in water. XRD, N2 sorption, TEM, and solid-state NMR spectroscopy reveal that mesoporous Ph-PMO supports and Pd/Ph-PMO catalysts have highly ordered 2D hexagonal mesostructures and covalently bonded organic,inorganic (all Si atoms bonded with carbon) hybrid frameworks. In the Ullmann coupling reaction of iodobenzene in water, the yield of biphenyl was 94,%, 34,%, 74,% and for palladium-supported Ph-PMO, pure silica (MCM-41), and phenyl-group-modified Ph-MCM-41 catalysts, respectively. The selectivity toward biphenyl reached 91,% for the coupling of boromobenzene on the Pd/Ph-PMO catalyst. This value is much higher than that for Pd/Ph-MCM-41 (19,%) and Pd/MCM-41 (0,%), although the conversion of bromobenzene for these two catalysts is similar to that for Pd/Ph-PMO. The large difference in selectivity can be attributed to surface hydrophobicity, which was evaluated by the adsorption isotherms of water and toluene. Ph-PMO has the most hydrophobic surface, and in turn selectively adsorbs the reactant haloaryls from aqueous solution. Water transfer inside the mesochannels is thus restricted, and the coupling reaction of bromobenzene is improved. [source]

Ground Water Transfer Initiates Complete Reductive Dechlorination in a PCE-Contaminated Aquifer

Improvement of the hydrological component of an urban soil,vegetation,atmosphere,transfer model

HYDROLOGICAL PROCESSES, Issue 16 2007
A. Lemonsu
Abstract A numerical study was conducted on the Rezé suburban catchment (Nantes, France) to evaluate the hydrological component of the town energy balance (TEB) scheme, which simulates in a coupled way the water and energy balances for the urban covers. The catchment is a residential area where hydrological data were continuously collected from 1993 to 1998 by the Laboratoire Central des Ponts et Chaussées (LCPC), notably the runoff in the stormwater drainage network. A 6-year simulation with the TEB and interaction soil,biosphere,atmosphere (ISBA) schemes in off-line mode enabled the comparison of modelled and observed runoff. Some weaknesses of the TEB were uncovered and led to improved parameterization of water exchanges: (1) calibration of the maximum capacity of the rainfall interception reservoir on roads and roofs and (2) inclusion of water infiltration through the roads, according to a simple formulation. The calibration of this water flux gives results that are consistent with direct measurements of water infiltration performed on the Rezé site and from the literature. The new parameterization produces better runoff in terms of timing and magnitude, which are comparable to those obtained by the LCPC with other hydrological models. It shows also the impact of the water infiltration through the roads, corresponding to a water transfer from the TEB to ISBA, on the water balance: the water contents of road, roof and soil reservoirs being modified, the evaporation from artificial surfaces decreases, while the evapotranspiration from natural covers increases. Through the evaporative flux, such a modification of the water balance induces large repercussions on the surface energy balance. Copyright © 2007 John Wiley & Sons, Ltd. [source]

The GEOTOP snow module

HYDROLOGICAL PROCESSES, Issue 18 2004
Fabrizio Zanotti
Abstract A snow accumulation and melt module implemented in the GEOTOP model is presented and tested. GEOTOP, a distributed model of the hydrological cycle, based on digital elevation models (DEMs), calculates the discharge at the basin outlet and estimates the local and distributed values of several hydro-meteorological quantities. It solves the energy and the mass balance jointly and deals accurately with the effects of topography on the interactions among radiation physics, energy balance and the hydrological cycle. Soil properties are considered to depend on soil temperature and moisture, and the heat and water transfer in the soil is modelled using a multilayer approach. The snow module solves for the soil,snow energy and mass exchanges, and, together with a runoff production module, is embedded in a more general energy balance model that provides all the boundary conditions required. The snowpack is schematized as a single snow layer where a limited number of physical processes are described. The module can be seen essentially as a parameter-free model. The application to an alpine catchment (Rio Valbiolo, Trentino, Italy), monitored by an in situ snow-depth sensor, is discussed and shown to give results comparable to those of more complex models. Copyright © 2004 John Wiley & Sons, Ltd. [source]

The simulation of heat and water exchange at the land,atmosphere interface for the boreal grassland by the land-surface model SWAP

HYDROLOGICAL PROCESSES, Issue 10 2002
Yeugeniy M. Gusev
Abstract The major goal of this paper is to evaluate the ability of the physically based land surface model SWAP to reproduce heat and water exchange processes that occur in mid-latitude boreal grassland regions characterized by a clear seasonal course of hydrometeorological conditions, deep snow cover, seasonally frozen soil, as well as seasonally mobile and shallow water table depth. A unique set of hydrometeorological data measured over 18 years (1966,83) at the Usadievskiy catchment (grassland) situated in the central part of Valdai Hills (Russia) provides an opportunity to validate the model. To perform such validation in a proper way, SWAP is modified to take into account a shallow water table depth. The new model differs from its previous version mainly in the parameterization of water transfer in a soil column; besides that, it includes soil water,groundwater interaction. A brief description of the new version of SWAP and the results of its validation are presented. Simulations of snow density, snow depth, snow water equivalent, daily snow surface temperature, daily evaporation from snow cover, water yield of snow cover, water table depth, depth of soil freezing and thawing, soil water storage in two layers, daily surface and total runoff from the catchment, and monthly evaporation from the catchment are validated against observations on a long-term basis. The root-mean-square errors (RMSEs) of simulations of soil water storage in the layers of 0,50 cm and 0,100 cm are equal to 16 mm and 24 mm respectively; the relative RMSE of simulated annual total runoff is 16%; the RMSE of daily snow surface temperature is 2·9 °C (the temperature varies from 0 to ,46 °C); the RMSE of maximum snow water equivalent (whose value averaged over 18 years is equal to 147 mm) is 32 mm. Analysis of the results of validation shows that the new version of the model SWAP reproduces the heat and water exchange processes occurring in mid-latitude boreal grassland reasonably well. Copyright © 2002 John Wiley & Sons, Ltd. [source]

Urban,agricultural water appropriation: the Hyderabad, India case

THE GEOGRAPHICAL JOURNAL, Issue 1 2010
MATTIA CELIO
With the urbanisation drive comes steady growth in urban water demand. Although in the past this new demand could often be met by tapping unclaimed water sources, this option is increasingly untenable in many regions where little if any unclaimed water remains. The result is that urban water capture, and the appropriation of associated physical and institutional infrastructure, now often implies conflict with other existing uses and users. While the urbanisation process has been studied in great depth, the processes and, critically, impacts of urban water capture and appropriation are not well researched or understood. This paper undertakes a critical examination of the specific case of Hyderabad, one of India's fastest growing cities, to shed light more generally on the process of water capture by cities and the resultant impacts on pre-existing claims, particularly agriculture. It does this by examining the history and institutional response to Hyderabad's urban,rural water contest; how the results of that contest are reflected in surface and groundwater hydrology; and the eventual impacts on agriculture. The findings show that the magnitude, and sometimes even direction, of impact from urban water transfer vary in space and time and depend on location-specific rainfall patterns, the nature of existing water infrastructure and institutions, and farmers' adaptive capacities and options, notably recourse to groundwater. Broader consideration of the specific findings provides insights into policy mechanisms to reduce the possible negative impacts from the global, and seemingly inexorable, flow of water to the world's growing cities. [source]

Structure of the Lining Epithelium of the Cauda Epididymis of the Golden Hamster

ANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 1 2009
C. C. L. Beu
Summary The ductus epididymis has roles in the maturation and storage of spermatozoa. The main function of the cauda epididymis is the storage of spermatozoa; however, this region exerts other morphophysiological roles. So, this study was aimed at investigating structural features of the cauda epididymis epithelium, which could indicate roles other than the storage. The relative percentages of the cell types in the epithelium were 74.9, 6.9, 12.5 and 5.6% of principal, clear, basal and halo cells respectively. Large intercellular spaces were seen among the lateral plasmatic membranes of adjacent principal cells or among these cells and others cell types. These spaces were found to be filled with multivesicular bodies, myelin figures, scrolls and debris of membranes or flocculent dense material. Clear cells had the cytoplasms filled with lysosomes (¾ of basal cytoplasm), and vacuoles and vesicles (¼ of apical cytoplasm). The observations allowed us to infer that clear cells could act in the process of endocytosis and also in water transfer from the lumen to the interstitium through the epithelium compartment. Moreover, transcytosis may occur at the cauda epididymis of Golden hamster. [source]

Water rights and legal pluralism: four contexts for negotiation

NATURAL RESOURCES FORUM, Issue 1 2001
Bryan Randolph Bruns
Abstract Increasing water scarcity is increasing pressure on water management institutions, particularly in the area of water rights. A common response is to formalise water tenure, one of several options for securing access and resolving conflicts concerning water allocation. This article looks at four contexts where negotiation, self-governance and concepts of legal pluralism may help improve water resource management. Existing users and potential new users need to negotiate before water resources are developed. Users can participate in forums with authority to solve basin management problems through self-governance. Negotiated water transfers offer an alternative to water acquisition by expropriation. [source]