WorldWideScience

Sample records for solution water motor

  1. 2010 Water & Aqueous Solutions

    Energy Technology Data Exchange (ETDEWEB)

    Dor Ben-Amotz

    2010-08-13

    Water covers more than two thirds of the surface of the Earth and about the same fraction of water forms the total mass of a human body. Since the early days of our civilization water has also been in the focus of technological developments, starting from converting it to wine to more modern achievements. The meeting will focus on recent advances in experimental, theoretical, and computational understanding of the behavior of the most important and fascinating liquid in a variety of situations and applications. The emphasis will be less on water properties per se than on water as a medium in which fundamental dynamic and reactive processes take place. In the following sessions, speakers will discuss the latest breakthroughs in unraveling these processes at the molecular level: Water in Solutions; Water in Motion I and II; Water in Biology I and II; Water in the Environment I and II; Water in Confined Geometries and Water in Discussion (keynote lecture and poster winners presentations).

  2. Canned motor pumps at Heavy Water Project, Baroda

    International Nuclear Information System (INIS)

    Batra, R.K.; Waishampayan, S.C.

    1981-01-01

    Pumps to be used in heavy water plants must be reliable and should require negligible maintenance, because most of them are totally unapproachable under normal circumstances. Canned motor pumps fulfil these requirements. Their design features are described briefly. The details of: (1) the pumps in the isotopic exchange tower and (2) pumps for liquid ammonia and catalyst are given. Problems faced during commissioning of such pumps in Baroda Heavy Water Project were bulging of rotors of tower pumps, bulging of stators, jamming and failure of bearings. Solution of these problems is described. (M.G.B.)

  3. Dielectric Analysis for Torque of a Solute Ion Coulomb Force Monopole Motor

    Science.gov (United States)

    Fresco, Anthony N.

    ASME Technical Paper ES2010-90396 "Solute Ion Coulomb Force Monopole Motor and Solute Ion Linear Alignment Propulsion" by the author describes a motor that is based on an arrangement of solute ion electric field monopoles.[1] That is, through a process called capacitive deionization, sodium and chlorine ions in salt water are captured and confined by an electrically conductive material to form electric field monopoles. At least four of the like charged monopoles (all negative or all positive) can be arranged on a disc. At least one stationary monopole of the same charge is placed adjacent to the disc and positioned so that a repulsive electric field is formed between the stationary monopole and at least one of the monopoles positioned on the disc so that the disc is then forced to rotate a shaft at the center of the disc. This paper analyzes the behavior of the dielectric materials forming part of the monopoles to show that the net torque on the motor is greater than zero and also illustrates a novel effect of polarization of a dielectric material positioned between two like-charged monopoles as occurs in the configuration of the monopole motor and a deficiency in the conventional closed path analysis for work performed during movement of electric charges that emit electrostatic fields by failing to consider the effects of dielectric materials in shielding the electrostatic fields. The monopole motor connected to an to electrical generator can provide continuous on-board electrical power to electrical loads for local and deep space applications including power to electrode assemblies designed for linear alignment of like-charged solute ions as a means of propulsion and particle acceleration as described in the ES2010-90396 paper. Details of the monopole motor and the propulsion are available in WO 2008/024927 A2 (and US2010/0199632 A1) "Solute Ion Coulomb Force Acceleration and Electric Field Monopole Passive Voltage Source" by the author Ref.[2].

  4. Water Pollution (Causes, Mechanisms, Solution).

    Science.gov (United States)

    Strandberg, Carl

    Written for the general public, this book illustrates the causes, status, problem areas, and prediction and control of water pollution. Water pollution is one of the most pressing issues of our time and the author communicates the complexities of this problem to the reader in common language. The purpose of the introductory chapter is to show what…

  5. Pretreatment Solution for Water Recovery Systems

    Science.gov (United States)

    Muirhead, Dean (Inventor)

    2018-01-01

    Chemical pretreatments are used to produce usable water by treating a water source with a chemical pretreatment that contains a hexavalent chromium and an acid to generate a treated water source, wherein the concentration of sulfate compounds in the acid is negligible, and wherein the treated water source remains substantially free of precipitates after the addition of the chemical pretreatment. Other methods include reducing the pH in urine to be distilled for potable water extraction by pretreating the urine before distillation with a pretreatment solution comprising one or more acid sources selected from a group consisting of phosphoric acid, hydrochloric acid, and nitric acid, wherein the urine remains substantially precipitate free after the addition of the pretreatment solution. Another method described comprises a process for reducing precipitation in urine to be processed for water extraction by mixing the urine with a pretreatment solution comprising hexavalent chromium compound and phosphoric acid.

  6. WaterNet: The NASA Water Cycle Solutions Network

    Science.gov (United States)

    Houser, P. R.; Belvedere, D. R.; Pozzi, W. H.; Imam, B.; Schiffer, R.; Lawford, R.; Schlosser, C. A.; Gupta, H.; Welty, C.; Vorosmarty, C.; Matthews, D.

    2007-12-01

    Water is essential to life and directly impacts and constrains society's welfare, progress, and sustainable growth, and is continuously being transformed by climate change, erosion, pollution, and engineering practices. The water cycle is a critical resource for industry, agriculture, natural ecosystems, fisheries, aquaculture, hydroelectric power, recreation, and water supply, and is central to drought, flood, transportation-aviation, and disease hazards. It is therefore a national priority to use advancements in scientific observations and knowledge to develop solutions to the water challenges faced by society. NASA's unique role is to use its view from space to improve water and energy cycle monitoring and prediction. NASA has collected substantial water cycle information and knowledge that must be transitioned to develop solutions for all twelve National Priority Application (NPA) areas. NASA cannot achieve this goal alone -it must establish collaborations and interoperability with existing networks and nodes of research organizations, operational agencies, science communities, and private industry. Therefore, WaterNet: The NASA Water Cycle Solutions Network goal is to improve and optimize the sustained ability of water cycle researchers, stakeholders, organizations and networks to interact, identify, harness, and extend NASA research results to augment decision support tools and meet national needs. WaterNet is a catalyst for discovery and sharing of creative solutions to water problems. It serves as a creative, discovery process that is the entry-path for a research-to-solutions systems engineering NASA framework, with the end result to ultimately improve decision support.

  7. Effects of a water activity intervention programme on motor ...

    African Journals Online (AJOL)

    The aim of this study was to investigate the effect of a specially designed water activity programme on the motor competency levels of children with Down's syndrome. Six institutionalised children classified as having Down\\'s syndrome, from a school for the mentally retarded, took part in the study. The children\\'s ...

  8. Desalination - A solution to water shortage

    International Nuclear Information System (INIS)

    Shakaib, M.

    2005-01-01

    Pakistan as well as neighbouring countries are faced with critical water shortage for the last few decades. The demand for water has outstripped its supply making the availability of safe water sources an issue Also conflicts over water sharing are expected in many regions of the world. Thus, because of this looming crisis water problems are getting increasing attention all over the world. With the advancement of desalination technology many countries had resorted removal of salts from brackish and sea water as an alternative water supply and they are now viewing desalination as a future solution to problems of lack of water. Today, over 100 countries use desalting requirement. A total of 12,451 desalting units (of a unit size of 100 m/sup 3//d or more) with a total capacity of 22,735,000 m /d had been installed or contracted worldwide. Brackish water desalination plants contribute with 9,400,000 m3/d, whereas the capacity of the sea water plants had reached up to 13,300,000 m3/d. This paper will discuss the use of desalination to produce potable water from saline water for domestic or municipal purposes and also the available desalination techniques that have been developed over the years and have achieved commercial success. (author)

  9. 49 CFR 1090.3 - Use of TOFC/COFC service by motor and water carriers.

    Science.gov (United States)

    2010-10-01

    ... authorized service. (b) Motor and water common carriers may use rail TOFC/COFC service only if their tariff... common or water contract carriers providing for the use of rail TOFC/COFC service shall set forth the... motor and water carriers. (a) Except as otherwise prohibited by these rules, motor and water common and...

  10. CNT based thermal Brownian motor to pump water in nanodevices

    DEFF Research Database (Denmark)

    Oyarzua, Elton; Zambrano, Harvey; Walther, Jens Honore

    2016-01-01

    asymmetry drive the water ow in a preferential direction. We systematically modified the magnitude of the applied thermal gradient and the axial position of the fixed points. The analysis involves measurement of the vibrational modes in the CNTs using a Fast Fourier Transform (FFT) algorithm. We observed......Brownian molecular motors are nanoscale machines that exploit thermal fluctuations for directional motion by employing mechanisms such as the Feynman-Smoluchowski ratchet. In this study, using Non Equilibrium Molecular Dynamics, we propose a novel thermal Brownian motor for pumping water through...... Carbon Nanotubes (CNTs). To achieve this we impose a thermal gradient along the axis of a CNT filled with water and impose, in addition, a spatial asymmetry by flxing specific zones on the CNT in order to modify the vibrational modes of the CNT. We find that the temperature gradient and imposed spatial...

  11. Energy-Water System Solutions | Energy Analysis | NREL

    Science.gov (United States)

    System Solutions Energy-Water System Solutions NREL has been a pioneer in the development of energy -water system solutions that explicitly address and optimize energy-water tradeoffs. NREL has evaluated energy-water system solutions for Department of Defense bases, islands, communities recovering from

  12. Recirculating cooling water solute depletion models

    International Nuclear Information System (INIS)

    Price, W.T.

    1990-01-01

    Chromates have been used for years to inhibit copper corrosion in the plant Recirculating Cooling Water (RCW) system. However, chromates have become an environmental problem in recent years both in the chromate removal plant (X-616) operation and from cooling tower drift. In response to this concern, PORTS is replacing chromates with Betz Dianodic II, a combination of phosphates, BZT, and a dispersant. This changeover started with the X-326 system in 1989. In order to control chemical concentrations in X-326 and in systems linked to it, we needed to be able to predict solute concentrations in advance of the changeover. Failure to predict and control these concentrations can result in wasted chemicals, equipment fouling, or increased corrosion. Consequently, Systems Analysis developed two solute concentration models. The first simulation represents the X-326 RCW system by itself; and models the depletion of a solute once the feed has stopped. The second simulation represents the X-326, X-330, and the X-333 systems linked together by blowdown. This second simulation represents the concentration of a solute in all three systems simultaneously. 4 figs

  13. Access to water: Technical and social solutions help communities ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    2010-12-08

    Dec 8, 2010 ... English · Français ... Access to water: Technical and social solutions help communities make the most of ... IDRC-supported research engages communities, and countries, in developing durable solutions to water problems.

  14. 36 CFR 13.1180 - Closed waters, motor vessels and seaplanes.

    Science.gov (United States)

    2010-07-01

    ... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false Closed waters, motor vessels... and Preserve Vessel Operating Restrictions § 13.1180 Closed waters, motor vessels and seaplanes. (a... Hugh Miller Inlet. (4) Waters within the Beardslee Island group (except the Beardslee Entrance), that...

  15. Structure of water and the thermodynamics of aqueous solutions

    Energy Technology Data Exchange (ETDEWEB)

    Nemethy, G.

    1970-10-26

    This report represents the summary of a series of lectures held at the Istituto Superiore di Sanita, Laboratori di Fisica, from 18 September to 26 October 1970. The topics discussed were: Intermolecular forces, the individual water molecule and the hydrogen bond, the structures of the solid phases of water, experimental information on the strucuture of liquid water, theoretical models of water structure, experimental properties and theoretical models of aqueous solutions of nonpolar solutes, polar solutes, and electrolytes, the conformational stability of biological macromolecules.

  16. Acidities of Water and Methanol in Aqueous Solution and DMSO

    Science.gov (United States)

    Gao, Daqing

    2009-01-01

    The relative acidities of water and methanol have been a nagging issue. In gas phase, methanol is more acidic than water by 36.0 kJ/mol; however, in aqueous solution, the acidities of methanol and water are almost identical. The acidity of an acid in solution is determined by both the intrinsic gas-phase ionization Gibbs energy and the solvent…

  17. Smart solutions to a worsening water crisis | IDRC - International ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    2013-01-23

    Jan 23, 2013 ... Innovative policies and new technologies that reduce water waste are helping countries across the Middle East and North Africa deal with chronic ... Home · Resources · Publications. Smart solutions to a worsening water crisis.

  18. Hydrogen/deuterium substitution methods: understanding water structure in solution

    International Nuclear Information System (INIS)

    Soper, A.K.

    1993-01-01

    The hydrogen/deuterium substitution method has been used for different applications, such as the short range order between water molecules in a number of different environments (aqueous solutions of organic molecules), or to study the partial structure factors of water at high pressure and temperature. The absolute accuracy that can be obtained remains uncertain, but important qualitative information can be obtained on the local organization of water in aqueous solution. Some recent results with pure water, methanol and dimethyl sulphoxide (DMSO) solutions are presented. It is shown that the short range water structure is not greatly affected by most solutes except at high concentrations and when the solute species has its own distinctive interaction with water (such as a dissolved small ion). 3 figs., 14 refs

  19. NASA's Water Solutions Using Remote Sensing

    Science.gov (United States)

    Toll, David

    2012-01-01

    NASA Water Resources works within Earth sciences to leverage investments of space-based observation, model results, and development and deployment of enabling technologies, systems, and capabilities into water resources management decision support tools for the sustainable use of water. Earth science satellite observations and modelling products provide a huge volume of valuable data in both near-real-time and extended back nearly 50 years about the Earth's land surface conditions such as land cover type, vegetation type and health, precipitation, snow, soil moisture, and water levels and radiation. Observations of this type combined with models and analysis enable satellite-based assessment of the water cycle. With increasing population pressure and water usage coupled with climate variability and change, water issues are being reported by numerous groups as the most critical environmental problems facing us in the 21st century. Competitive uses and the prevalence of river basins and aquifers that extend across boundaries engender political tensions between communities, stakeholders and countries. The NASA Water Resources Program has the objective to provide NASA products to help deal with these issues with the goal for the sustainable use of water. The Water Resources program organizes its projects under five functional themes: 1) stream-flow and flood forecasting; 2) water consumptive use (includes evapotranspiration) and irrigation; 3) drought; 4) water quality; and 5) climate and water resources. NASA primarily works with national and international groups such as other US government agencies (NOAA, EPA, USGS, USAID) and various other groups to maximize the widest use of the water products. A summary of NASA's water activities linked to helping solve issues for developing countries will be highlighted.

  20. Access to water: Technical and social solutions help communities ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Access to water: Technical and social solutions help communities make the most of available sources. 08 décembre 2010. Image. IDRC Communications. LASTING IMPACTS. IDRC-supported research engages communities, and countries, in developing durable solutions to water problems. Whatever the challenge, people ...

  1. Enthalpy of solution of rubidium nitrate in water

    International Nuclear Information System (INIS)

    Weintraub, R.; Apelblat, A.; Tamir, A.

    1984-01-01

    Molar enthalpies of solution of RbNO 3 in water at 298.15 K were measured in an LKB calorimeter. The molar enthalpies of solution extrapolated to infinite solution are: (36788 +- 30)J. mol -1 (Alfa) and (36539 +- 52)J.mol -1 (Aldrich). (author)

  2. Treatment for hydrazine-containing waste water solution

    Science.gov (United States)

    Yade, N.

    1986-01-01

    The treatment for waste solutions containing hydrazine is presented. The invention attempts oxidation and decomposition of hydrazine in waste water in a simple and effective processing. The method adds activated charcoal to waste solutions containing hydrazine while maintaining a pH value higher than 8, and adding iron salts if necessary. Then, the solution is aerated.

  3. The Influence of Water and Mineral Oil On Volumetric Losses in a Hydraulic Motor

    Directory of Open Access Journals (Sweden)

    Śliwiński Pawel

    2017-04-01

    Full Text Available In this paper volumetric losses in hydraulic motor supplied with water and mineral oil (two liquids having significantly different viscosity and lubricating properties are described and compared. The experimental tests were conducted using an innovative hydraulic satellite motor, that is dedicated to work with different liquids, including water. The sources of leaks in this motor are also characterized and described. On this basis, a mathematical model of volumetric losses and model of effective rotational speed have been developed and presented. The results of calculation of volumetric losses according to the model are compared with the results of experiment. It was found that the difference is not more than 20%. Furthermore, it has been demonstrated that this model well describes in both the volumetric losses in the motor supplied with water and oil. Experimental studies have shown that the volumetric losses in the motor supplied with water are even three times greater than the volumetric losses in the motor supplied with oil. It has been shown, that in a small constant stream of water the speed of the motor is reduced even by half in comparison of speed of motor supplied with the same stream of oil.

  4. Integrated Solution Support System for Water Management

    NARCIS (Netherlands)

    Kassahun, A.; Blind, M.; Krause, A.U.M.; Roosenschoon, O.R.

    2008-01-01

    Solving water management problems involves technical, social, economic, political and legal challenges and thus requires an integrated approach involving people from different backgrounds and roles. The integrated approach has been given a prominent role within the European Union¿s Water Framework

  5. Effects of Water Solutions on Extracting Green Tea Leaves

    Directory of Open Access Journals (Sweden)

    Wen-Ying Huang

    2013-01-01

    Full Text Available This study investigates the effects of water solutions on the antioxidant content of green tea leaf extracts. Green teas prepared with tap water and distilled water were compared with respect to four antioxidant assays: total phenol content, reducing power, DMPD assay, and trolox equivalent antioxidant capacity assay. The results indicate that green tea prepared with distilled water exhibits higher antioxidant activity than that made with tap water. The high performance liquid chromatography showed that major constituents of green tea were found in higher concentrations in tea made with distilled water than in that made with tap water. This could be due to less calcium fixation in leaves and small water clusters. Water solutions composed of less mineralisation are more effective in promoting the quality of green tea leaf extracts.

  6. Anomalous water diffusion in salt solutions

    Science.gov (United States)

    Ding, Yun; Hassanali, Ali A.; Parrinello, Michele

    2014-01-01

    The dynamics of water exhibits anomalous behavior in the presence of different electrolytes. Recent experiments [Kim JS, Wu Z, Morrow AR, Yethiraj A, Yethiraj A (2012) J Phys Chem B 116(39):12007–12013] have found that the self-diffusion of water can either be enhanced or suppressed around CsI and NaCl, respectively, relative to that of neat water. Here we show that unlike classical empirical potentials, ab initio molecular dynamics simulations successfully reproduce the qualitative trends observed experimentally. These types of phenomena have often been rationalized in terms of the “structure-making” or “structure-breaking” effects of different ions on the solvent, although the microscopic origins of these features have remained elusive. Rather than disrupting the network in a significant manner, the electrolytes studied here cause rather subtle changes in both structural and dynamical properties of water. In particular, we show that water in the ab initio molecular dynamics simulations is characterized by dynamic heterogeneity, which turns out to be critical in reproducing the experimental trends. PMID:24522111

  7. No Solutions: Resisting Certainty in Water Supply Management

    Science.gov (United States)

    Cockerill, K.; Armstrong, M.; Richter, J.; Okie, J. G.

    2017-12-01

    Although most scholars and water managers implicitly understand that managing water resources is an ongoing need, both popular and academic literature routinely use the words `solution' and `solve' in discussing water management concerns. The word `solution' reflects a quest for certainty, stability, permanence. A focus on `solving' creates a simplistic expectation that some person or institution is responsible for implementing a solution and that once `solved' the issue no longer requires attention. The reality, however, is water management is a wicked problem, meaning it is amorphous, involves multiple definitions, is embedded in complex systems, and hence is intractable. By definition, wicked problems defy solution. Our interdisciplinary project integrates research from across a broad spectrum of biological, physical, and social sciences. We find that framing a problem in terms of `solving' affects how people think, feel, behave toward the problem. Further, our work suggests that the prevalence of solution- based language has simultaneously generated expectations that science / scientists can predict and control biophysical systems and that science is not to be trusted because it has failed to deliver on previous promises to permanently `solve' events like floods or droughts. Hydrologic systems, are, of course highly uncertain. Hence, reiterating a simplistic insistence on `solving' water management concerns may result in decreased public attention to or support for more complex policy discussions that could provide long-term management strategies. Using the language of `solutions' with expectations of certainty sets hydrologic researchers and water managers up to fail. Managing water is a social responsibility and it will require consistent attention in the future, just as it has throughout human history. Scientists have a key role to play in explaining how various hydrologic systems function, but they should not be expected to `solve' pressing water management

  8. Industrial Water Waste, Problems and the Solution

    Directory of Open Access Journals (Sweden)

    Alif Noor Anna

    2004-01-01

    Full Text Available Recently, the long term development in Indonesia has changed agricultural sector to the industrial sector. This development can apparently harm our own people. This is due to the waste that is produced from factories. The waste from various factories seems to have different characteristics. This defference encourages us to be able to find out different of methods of managing waste so that cost can be reduced, especially in water treatment. In order that industrial development and environmental preservation can run together in balance, many institutions involved should be consider, especially in the industrial chain, the environment, and human resource, these three elements can be examined in terms of their tolerance to waste.

  9. Analysis of the Numerical Solution of the Shallow Water Equations

    National Research Council Canada - National Science Library

    Hamrick, Thomas

    1997-01-01

    .... The two schemes are finite difference method (FDM) and the finite element method (FEM). After presenting the shallow water equations in several formulations, some examples will be presented. The use of the Fourier transform to find the solution of a semidiscrete analog of the shallow water equations is also demonstrated.

  10. QENS and NMR studies of 3-picoline-water solutions

    CERN Document Server

    Almasy, L; Bokor, M; Cser, L; Tompa, K; Zanotti, J M; Jancso, G

    2002-01-01

    Quasi-elastic neutron scattering measurements were performed on aqueous solutions of 3-picoline (3-methylpyridine) at room temperature. H-D substitution on both the solute and the water was used to separate the dynamics of the two species. The analysis of the translational diffusive motion at different concentrations shows that at high picoline content the diffusion coefficient of water decreases strongly and becomes similar to that of the solute, indicating strong coupling between the motions of the solute and the solvent. Activation energies characteristic of the dynamic behavior of the methyl group were determined from sup 1 H spin-lattice relaxation rate measurements for H sub 2 O and D sub 2 O solutions of 3-picoline above 310 K. (orig.)

  11. Water Evaporation from Acoustically Levitated Aqueous Solution Droplets.

    Science.gov (United States)

    Combe, Nicole A; Donaldson, D James

    2017-09-28

    We present a systematic study of the effect of solutes on the evaporation rate of acoustically levitated aqueous solution droplets by suspending individual droplets in a zero-relative humidity environment and measuring their size as a function of time. The ratios of the early time evaporation rates of six simple salts (NaCl, NaBr, NaNO 3 , KCl, MgCl 2 , CaCl 2 ) and malonic acid to that of water are in excellent agreement with predictions made by modifying the Maxwell equation to include the time-dependent water activity of the evaporating aqueous salt solution droplets. However, the early time evaporation rates of three ammonium salt solutions (NH 4 Cl, NH 4 NO 3 , (NH 4 ) 2 SO 4 ) are not significantly different from the evaporation rate of pure water. This finding is in accord with a previous report that ammonium sulfate does not depress the evaporation rate of its solutions, despite reducing its water vapor pressure, perhaps due to specific surface effects. At longer evaporation times, as the droplets approach crystallization, all but one (MgCl 2 ) of the solution evaporation rates are well described by the modified Maxwell equation.

  12. Shallow water equations: viscous solutions and inviscid limit

    Science.gov (United States)

    Chen, Gui-Qiang; Perepelitsa, Mikhail

    2012-12-01

    We establish the inviscid limit of the viscous shallow water equations to the Saint-Venant system. For the viscous equations, the viscosity terms are more degenerate when the shallow water is close to the bottom, in comparison with the classical Navier-Stokes equations for barotropic gases; thus, the analysis in our earlier work for the classical Navier-Stokes equations does not apply directly, which require new estimates to deal with the additional degeneracy. We first introduce a notion of entropy solutions to the viscous shallow water equations and develop an approach to establish the global existence of such solutions and their uniform energy-type estimates with respect to the viscosity coefficient. These uniform estimates yield the existence of measure-valued solutions to the Saint-Venant system generated by the viscous solutions. Based on the uniform energy-type estimates and the features of the Saint-Venant system, we further establish that the entropy dissipation measures of the viscous solutions for weak entropy-entropy flux pairs, generated by compactly supported C 2 test-functions, are confined in a compact set in H -1, which yields that the measure-valued solutions are confined by the Tartar-Murat commutator relation. Then, the reduction theorem established in Chen and Perepelitsa [5] for the measure-valued solutions with unbounded support leads to the convergence of the viscous solutions to a finite-energy entropy solution of the Saint-Venant system with finite-energy initial data, which is relative with respect to the different end-states of the bottom topography of the shallow water at infinity. The analysis also applies to the inviscid limit problem for the Saint-Venant system in the presence of friction.

  13. Radiation-chemical degradation of chloroform in water solutions

    International Nuclear Information System (INIS)

    Ahmadov, S.A.; Gurbanov, M.A.; Iskenderova, Z.I.; Abdullayev, E.T.; Ibadov, N.A.

    2006-01-01

    Full text: Chloroform is the major chlorine-containing compound forming at chlorination of drinking water. As our basic water resources of Kur and Araz rivers are mostly polluted along the territory of the neighbour republics their chlorination for the purpose of biological purification can result in forming of chloroform. Unfortunately, there are only poor data about containing of chloroform in drinking water in the Republic, however the particular problem is to develop new methods of drinking water purification from chloroform, taking into account the high toxicity of this compounds. Appropriate works indicate that radiation-chemical processing can mostly reduce the concentration of chloroform in drinking water. The purification degree can achieve 95-98 percent. This work studies the tendency of chloroform decomposition at its radiolysis processes in water solutions. The concentration of chloroform changed in the range of 0,03-1 weight percentage. Taking into account the dissolvability of chloroform in water solutions it can be said that examined water solutions are homogeneous. Following advancements are studied: 1) Determination of radiation-chemical yield of chloroform decomposition at its various initial concentrations; 2) Impact of adsorbed dose on pH of solutions; 3) Formation of by-products. It is set that radiation-chemical output of chloroform decomposition is equal to 3 * 10 - 3 - 125 mol/100 ev. The high yield of chloroform decomposition can be connected with the chain process of oxidation with presence of dissolved oxygen. However, taking into account the fact that at its water radiolysis the yield of active particles of OH, e - aq, H-atoms does not exceed 6-7 particles/100 ev, the observed high yield can be explained only with the chain process with presence of dissolved oxygen

  14. Radiation-chemical degradation of chloroform in water solutions

    International Nuclear Information System (INIS)

    Ahmadov, S.A; Gurbanov, M.A; Iskenderova, Z.I; Abdullaev, E.T; Ibadov, N.A.

    2006-01-01

    Full text: Chloroform is the major chlorine-containing compound forming at chlorination of drinking water. As our basic water resources of Kur and Araz rivers are mostly polluted along the territory of the neighbor republics their chlorination for the purpose of biological purification can result in forming of chloroform. Unfortunately, there are only poor data about containing of chloroform in drinking water in the Republic, however the particular problem is to develop new methods of drinking water purification from chloroform, taking into account the high toxicity of this compounds. Appropriate works indicate that radiation-chemical processing can mostly reduce the concentration of chloroform in drinking water. The purification degree can achieve 95-98%. This work studies the tendency of chloroform decomposition at its radiolysis processes in percentage. Taking into account the dissolvability of chloroform in water solutions it can be said that examined water solutions are homogeneous. Following advancements are studied: b Determination of radiation-chemical yield of chloroform decomposition at its various initial concentrations;Impact of adsorbed dose on pH of solutions;Formation of by-products.It is set that radiation-chemical output of chloroform decomposition is equal to 3.10-3-125 mol 100ev.

  15. The thermodynamic water retention capacity of solutions and gels.

    Science.gov (United States)

    Borchard, W; Jablonski, P

    2003-01-01

    The thermodynamic water retention capacity (WRC) has been defined and applied to different heterogeneous phase equilibria. This definition includes others known from the literature for testing heterogeneous systems. For the type of a real solution it is shown that at constant values of temperature and pressure the WRC is related to the difference of the chemical potential of water between the original state and the state after having applied a constraint. The dependence of WRC on concentration of a solute is predicted to be described by an e-function which has been experimentally confirmed in the literature.

  16. MSWT-01, flood disaster water treatment solution from common ideas

    Science.gov (United States)

    Ananto, Gamawan; Setiawan, Albertus B.; Z, Darman M.

    2013-06-01

    Indonesia has a lot of potential flood disaster places with clean water problems faced. Various solution programs always initiated by Government, companies CSR, and people sporadical actions to provide clean water; with their advantages and disadvantages respectively. One solution is easy to operate for instance, but didn't provide adequate capacity, whereas the other had ideal performance but more costly. This situation inspired to develop a water treatment machine that could be an alternative favor. There are many methods could be choosed; whether in simple, middle or high technology, depends on water source input and output result quality. MSWT, Mobile Surface Water Treatment, is an idea for raw water in flood area, basically made for 1m3 per hour. This water treatment design adopted from combined existing technologies and related literatures. Using common ideas, the highlight is how to make such modular process put in compact design elegantly, and would be equipped with mobile feature due to make easier in operational. Through prototype level experiment trials, the machine is capable for producing clean water that suitable for sanitation and cooking/drinking purposes although using contaminated water input source. From the investment point of view, such machine could be also treated as an asset that will be used from time to time when needed, instead of made for project approach only.

  17. MSWT-01, flood disaster water treatment solution from common ideas

    International Nuclear Information System (INIS)

    Ananto, Gamawan; Setiawan, Albertus B; Darman M Z

    2013-01-01

    Indonesia has a lot of potential flood disaster places with clean water problems faced. Various solution programs always initiated by Government, companies CSR, and people sporadical actions to provide clean water; with their advantages and disadvantages respectively. One solution is easy to operate for instance, but didn't provide adequate capacity, whereas the other had ideal performance but more costly. This situation inspired to develop a water treatment machine that could be an alternative favor. There are many methods could be choosed; whether in simple, middle or high technology, depends on water source input and output result quality. MSWT, Mobile Surface Water Treatment, is an idea for raw water in flood area, basically made for 1m 3 per hour. This water treatment design adopted from combined existing technologies and related literatures. Using common ideas, the highlight is how to make such modular process put in compact design elegantly, and would be equipped with mobile feature due to make easier in operational. Through prototype level experiment trials, the machine is capable for producing clean water that suitable for sanitation and cooking/drinking purposes although using contaminated water input source. From the investment point of view, such machine could be also treated as an asset that will be used from time to time when needed, instead of made for project approach only.

  18. Solution enthalpies of alkali metal halides in water and heavy water mixtures with dimethyl sulfoxide

    International Nuclear Information System (INIS)

    Egorov, G.I.

    1994-01-01

    Solution enthalpies of CsF, LiCl, NaI, CsI and some other halides of alkali metals and tetrabutylammonium have been measured by the method of calorimetry. Standard solution enthalpies of all alkali metals (except rubidium) halides in water and heavy water mixtures with dimethylsulfoxide at 298.15 K have been calculated. Isotopic effects in solvation enthalpy of the electrolytes mentioned in aqueous solutions of dimethylsulfoxide have been discussed. 29 refs., 2 figs., 4 tabs

  19. Heterogeneous primary nucleation of ice in water and aqueous solutions

    NARCIS (Netherlands)

    Thijssen, H.A.C.; Vorstman, M.A.G.; Roels, J.A.

    1968-01-01

    The effect of the volume of the liquid sample, the degree of turbulence in the liquid, and the rate of cooling upon the probability of nucleation has been studied for water and aqueous solutions. Nucleation rates were measured for droplets nearly instantaneously cooled to a predetermined

  20. Water hammer (with FSI): exact solution : parallelization and application

    NARCIS (Netherlands)

    Loh, K.; Tijsseling, A.S.

    2014-01-01

    The 1D fully coupled Fluid-Structure Interaction (FSI) model can adequately describe the water hammer effect on the fluid, and the structural behaviour of the pipe. This paper attempts to increase the capability of using an exact solution of the 1D FSI problem applied to a straight pipe with a

  1. Barriers and Solutions to Smart Water Grid Development.

    Science.gov (United States)

    Cheong, So-Min; Choi, Gye-Woon; Lee, Ho-Sun

    2016-03-01

    This limited review of smart water grid (SWG) development, challenges, and solutions provides an initial assessment of early attempts at operating SWGs. Though the cost and adoption issues are critical, potential benefits of SWGs such as efficient water conservation and distribution sustain the development of SWGs around the world. The review finds that the keys to success are the new regulations concerning data access and ownership to solve problems of security and privacy; consumer literacy to accept and use SWGs; active private sector involvement to coordinate SWG development; government-funded pilot projects and trial centers; and integration with sustainable water management.

  2. Analytical steady-state solutions for water-limited cropping systems using saline irrigation water

    Science.gov (United States)

    Skaggs, T. H.; Anderson, R. G.; Corwin, D. L.; Suarez, D. L.

    2014-12-01

    Due to the diminishing availability of good quality water for irrigation, it is increasingly important that irrigation and salinity management tools be able to target submaximal crop yields and support the use of marginal quality waters. In this work, we present a steady-state irrigated systems modeling framework that accounts for reduced plant water uptake due to root zone salinity. Two explicit, closed-form analytical solutions for the root zone solute concentration profile are obtained, corresponding to two alternative functional forms of the uptake reduction function. The solutions express a general relationship between irrigation water salinity, irrigation rate, crop salt tolerance, crop transpiration, and (using standard approximations) crop yield. Example applications are illustrated, including the calculation of irrigation requirements for obtaining targeted submaximal yields, and the generation of crop-water production functions for varying irrigation waters, irrigation rates, and crops. Model predictions are shown to be mostly consistent with existing models and available experimental data. Yet the new solutions possess advantages over available alternatives, including: (i) the solutions were derived from a complete physical-mathematical description of the system, rather than based on an ad hoc formulation; (ii) the analytical solutions are explicit and can be evaluated without iterative techniques; (iii) the solutions permit consideration of two common functional forms of salinity induced reductions in crop water uptake, rather than being tied to one particular representation; and (iv) the utilized modeling framework is compatible with leading transient-state numerical models.

  3. Isothermal dehydration of thin films of water and sugar solutions

    Energy Technology Data Exchange (ETDEWEB)

    Heyd, R. [Centre de Recherche sur la Matière Divisée, University of Orleans and CNRS, rue de la Férollerie 1B, 45071 Orléans Cedex 2 (France); Rampino, A. [Centre de Recherche sur la Matière Divisée, University of Orleans and CNRS, rue de la Férollerie 1B, 45071 Orléans Cedex 2 (France); Laboratory of Physical and Macromolecular Chemistry, University of Trieste, Via Giorgieri 1, 34127 Trieste (Italy); Bellich, B.; Elisei, E. [Laboratory of Physical and Macromolecular Chemistry, University of Trieste, Via Giorgieri 1, 34127 Trieste (Italy); Cesàro, A. [Laboratory of Physical and Macromolecular Chemistry, University of Trieste, Via Giorgieri 1, 34127 Trieste (Italy); Elettra Sincrotrone Trieste, Area Science Park, I-34149 Trieste (Italy); Saboungi, M.-L. [Centre de Recherche sur la Matière Divisée, University of Orleans and CNRS, rue de la Férollerie 1B, 45071 Orléans Cedex 2 (France); Institut de Minéralogie, de Physique des Matériaux, et de Cosmochimie (IMPMC), Sorbonne Univ-UPMC, Univ Paris 06, UMR CNRS 7590, Museum National d’Histoire Naturelle, IRD UMR 206, 4 Place Jussieu, F-75005 Paris (France)

    2014-03-28

    The process of quasi-isothermal dehydration of thin films of pure water and aqueous sugar solutions is investigated with a dual experimental and theoretical approach. A nanoporous paper disk with a homogeneous internal structure was used as a substrate. This experimental set-up makes it possible to gather thermodynamic data under well-defined conditions, develop a numerical model, and extract needed information about the dehydration process, in particular the water activity. It is found that the temperature evolution of the pure water film is not strictly isothermal during the drying process, possibly due to the influence of water diffusion through the cellulose web of the substrate. The role of sugar is clearly detectable and its influence on the dehydration process can be identified. At the end of the drying process, trehalose molecules slow down the diffusion of water molecules through the substrate in a more pronounced way than do the glucose molecules.

  4. Vibrational and orientational dynamics of water in aqueous hydroxide solutions.

    Science.gov (United States)

    Hunger, Johannes; Liu, Liyuan; Tielrooij, Klaas-Jan; Bonn, Mischa; Bakker, Huib

    2011-09-28

    We report the vibrational and orientational dynamics of water molecules in isotopically diluted NaOH and NaOD solutions using polarization-resolved femtosecond vibrational spectroscopy and terahertz time-domain dielectric relaxation measurements. We observe a speed-up of the vibrational relaxation of the O-D stretching vibration of HDO molecules outside the first hydration shell of OH(-) from 1.7 ± 0.2 ps for neat water to 1.0 ± 0.2 ps for a solution of 5 M NaOH in HDO:H(2)O. For the O-H vibration of HDO molecules outside the first hydration shell of OD(-), we observe a similar speed-up from 750 ± 50 fs to 600 ± 50 fs for a solution of 6 M NaOD in HDO:D(2)O. The acceleration of the decay is assigned to fluctuations in the energy levels of the HDO molecules due to charge transfer events and charge fluctuations. The reorientation dynamics of water molecules outside the first hydration shell are observed to show the same time constant of 2.5 ± 0.2 ps as in bulk liquid water, indicating that there is no long range effect of the hydroxide ion on the hydrogen-bond structure of liquid water. The terahertz dielectric relaxation experiments show that the transfer of the hydroxide ion through liquid water involves the simultaneous motion of ~7 surrounding water molecules, considerably less than previously reported for the proton. © 2011 American Institute of Physics

  5. A Mathematical Model of Solute Coupled Water Transport in Toad Intestine Incorporating Recirculation of the Actively Transported Solute

    DEFF Research Database (Denmark)

    Larsen, Erik Hviid; Sørensen, Jakob Balslev; Sørensen, Jens Nørkær

    2000-01-01

    those of tight junction and interspace basement membrane by convection-diffusion. With solute permeability of paracellular pathway large relative to paracellular water flow, the paracellular flux ratio of the solute (influx/outflux) is small (2-4) in agreement with experiments. The virtual solute......A mathematical model of an absorbing leaky epithelium is developed for analysis of solute coupled water transport. The non-charged driving solute diffuses into cells and is pumped from cells into the lateral intercellular space (lis). All membranes contain water channels with the solute passing...... increases with hydraulic conductance of the pathway carrying water from mucosal solution into lis. Uphill water transport is accomplished, but with high hydraulic conductance of cell membranes strength of transport is obscured by water flow through cells. Anomalous solvent drag occurs when back flux...

  6. Field-tested technology for gas compression: using high-speed induction motors to replace conventional solutions

    Energy Technology Data Exchange (ETDEWEB)

    Rodrigues, Karina Velloso; Pradurat, Jean Francois [Institut National Polytechnique de Lorraine (INPL), Nancy (France). Converteam Rotating Machines Division

    2009-07-01

    Industry leaders are all concerned about rationalization of electric power use, increase of efficiency and flexibility, environmental impact, installations size and maintenance efforts diminution. The high-speed induction motors are a good solution when addressing these parameters. How this technology works and how using it can help pipelines operators meet growing operational and environmental challenges is the main subject of this paper, that also explain how it can be used to replace conventional solutions. As a conclusion the future opportunities of electric high-speed drive systems application in production, transport and storage for natural gas industry are going to be discussed. (author)

  7. THE RELATIONS OF MORPHOLOGIC CHARACTERISTICS AND MOTOR ABILITIES OF JOUNG WATER POLO PLAYERS

    Directory of Open Access Journals (Sweden)

    Dragan Toskić

    2013-07-01

    Full Text Available The aim of our research was to determine the connection between morphologic characteristics and motor abilities of young water polo players. The sample of participants for this research can be defined as the population of water polo swimmers (N=60 aged 16 to 18, who were only included in the study under the condition that they have taken part in the water polo training process for a period of at least four years. In order to evaluate morphological characteristics of the participants we used 20 anthro¬po¬me¬tric variables (IBP to evaluated longitudinal and transversal dimenions, mass and body voluminosity and subcutaneous fatty tissue. In this study, the measurings of the sig¬ni¬ficant motor dimensions were carried by means of the following measuring instruments which the authors (Gredelj, Hošek, Metikoš, Momirović, 1975 had previously evaluated with the help of physiological mechanisms: the integration factor, based on the me¬cha¬nism for movement structure (MSK, the synergistic automatism and tonus regulation factor (SRT; the factor for excitation intensity regulation (RIE; the excitation duration re¬gulation factor (RTE. The relations between morphological and motor dimensions we¬re determined using a canonical correlation analysis. A correlation analysis was carried out and it indicated a very high correlation between dimesions morphological cha¬ra¬cte¬ri¬stics and motor abilities of young water polo players.

  8. Water and solute transport across the peritoneal membrane.

    Science.gov (United States)

    Morelle, Johann; Devuyst, Olivier

    2015-09-01

    We review the molecular mechanisms of peritoneal transport and discuss how a better understanding of these mechanisms is relevant for dialysis therapy. Peritoneal dialysis involves diffusion and osmosis through the highly vascularized peritoneal membrane. Computer simulations, expression studies and functional analyses in Aqp1 knockout mice demonstrated the critical role of the water channel aquaporin-1 (AQP1) in water removal during peritoneal dialysis. Pharmacologic regulation of AQP1, either through increased expression or gating, is associated with increased water transport in rodent models of peritoneal dialysis. Water transport is impaired during acute peritonitis, despite unchanged expression of AQP1, resulting from the increased microvascular area that dissipates the osmotic gradient across the membrane. In long-term peritoneal dialysis patients, the fibrotic interstitium also impairs water transport, resulting in ultrafiltration failure. Recent data suggest that stroke and drug intoxications might benefit from peritoneal dialysis and could represent novel applications of peritoneal transport in the future. A better understanding of the regulation of osmotic water transport across the peritoneum offers novel insights into the role of water channels in microvascular endothelia, the functional importance of structural changes in the peritoneal interstitium and the transport of water and solutes across biological membranes in general.

  9. Mobility of Hematite Submicron Particles in Water Solutions of Sugar

    International Nuclear Information System (INIS)

    Fornal, P.; Stanek, J.

    2008-01-01

    The mobility of the 100 nm Fe 2 O 3 particles in dense water solutions of sugar (sucrose) was determined from the analysis of the resonance absorption line shape of the Moessbauer spectra recorded in the -5 o C to 40 o C temperature range for different sugar concentrations. The discrepancy between the experimental data and the prediction of the classical theory of Brownian movement are interpreted in the term of the short observation time and the interaction between the solid particles in fluids, which extends in water up to 300 nm. The sedimentation process in the studied colloids was observed. (authors)

  10. Irradiation degradation of chlorpyrifos in water solution and asparagus

    International Nuclear Information System (INIS)

    Zhang Qingfang; Wang Feng; Ha Yiming; Li An; Yin Qinggang

    2009-01-01

    In order to seek an effective technique to degrade chlorpyrifos residue, chlorpyrifos water solution and asparagus containing chlorpyrifos as testing materials were irradiated by 60 Co γ-rays and their degradation rate were determined and compared. The results show the degradation rate in water-solution increases with irradiation dose in the range of 0 and 12 kGy, and it reached 95.5% at 4 kGy. The degradation rate of chlorpyrifos in asparagus is low and comes to the maximum of 30.0% when the dose is 8 kGy. Further study indicates that vitamin C, violaquercitrin and total sugar inhibit the irradiation degradation of chlorpyrifos in asparagus. (authors)

  11. Technical project for a new water purification solution

    Directory of Open Access Journals (Sweden)

    Toma Adina

    2018-01-01

    Full Text Available This research is part of the RO-BG Cross-Border Cooperation Program, project “CLEANDANUBE”, MIS-ETC 653, which has finalised by providing a common strategy to prevent the Danube’s pollution technological risks with oil and oil products. This paper presents a new sustainable water purification solution. A short introduction will be offered and an overview regarding the research and new methods to greening the waste is provided. The theoretical aspects of the centrifugal separation phenomenon are studied and the preliminary project bases were established. The paper conveys the possible constructive variations and the technological implications of those. Ultimately, the technical project for a new water purification solution and conclusions with critical points encountered during the designing phase are presented.

  12. Solar disinfection of drinking water and oral rehydration solutions

    Energy Technology Data Exchange (ETDEWEB)

    Acra, A; Raffoul, Z; Karahagopian, Y

    1984-01-01

    This document provides concise information on oral rehydration therapy for the control of diarrheal diseases in developing countries; however, the main emphasis has been placed on the disinfection of oral rehydration solutions, or the water used in their preparation, as achieved by exposure to sunlight in transparent containers. The fundamental principles of solar energy are presented as well as studies which demonstrate the efficacy of the method. 2 figures, 6 tables.

  13. Failure analysis of motor bearing of sea water pump in nuclear power plant

    International Nuclear Information System (INIS)

    Bian Chunhua; Zhang Wei

    2015-01-01

    The motor bearing of sea water pump in Qinshan Phase II Nuclear Power plant broke after only one year's using. This paper introduces failure analysis process of the motor bearing. Chemical composition analysis, metallic phase analysis, micrographic examination, and hardness analysis, dimension analysis of each part of the bearing, as well as the high temperature and low temperature performance analysis of lubricating grease are performed. According to the analysis above mentioned, the failure mode of the bearing is wearing, and the reason of wearing is inappropriate installation of the bearing. (authors)

  14. Used motor oil as a source of MTBE, TAME, and BTEX to ground water

    Science.gov (United States)

    Baker, R.J.; Best, E.W.; Baehr, A.L.

    2002-01-01

    Methyl tert-butyl ether (MTBE), the widely used gasoline oxygenate, has been identified as a common ground water contaminant, and BTEX compounds (benzene, toluene, ethylbenzene, and xylenes) have long been associated with gasoline spills. Because not all instances of ground water contamination by MTBE and BTEX can be attributed to spills or leaking storage tanks, other potential sources need to be considered. In this study, used motor oil was investigated as a potential source of these contaminants. MTBE in oil was measured directly by methanol extraction and gas chromatography using a flame ionization detector (GC/FID). Water was equilibrated with oil samples and analyzed for MTBE, BTEX, and the oxygenate tert-amyl methyl ether (TAME) by purge-and-trap concentration followed by GC/FID analysis. Raoult's law was used to calculate oil-phase concentrations of MTBE, BTEX, and TAME from aqueous-phase concentrations. MTBE, TAME, and BTEX were not detected in any of five new motor oil samples, whereas these compounds were found at significant concentrations in all six samples of the used motor oil tested for MTBE and all four samples tested for TAME and BTEX. MTBE concentrations in used motor oil were on the order of 100 mg/L. TAME concentrations ranged from 2.2 to 87 mg/L. Concentrations of benzene were 29 to 66 mg/L, but those of other BTEX compounds were higher, typically 500 to 2000 mg/L.

  15. Design and manufacturing of canned motors for exchange towers of heavy water plants (Preprint No. ED-4)

    International Nuclear Information System (INIS)

    Bhattacharya, S.; Badodkar, D.N.; Govindarajan, G.

    1989-04-01

    Canned motors which are specially munufactured for exchange towers of heavy water plants are supposed to be very reliable and rugged. Hence these motors are built with good safety margin in design. The efficiency of the motor is not the prime consideration but it should not fail under overload conditions. The designed output is higher than the output under normal operating condition. The failure of two pumps in one stage will need the opening of the tower and results in shutdown of the plant which will affect the production of heavy water. Keeping these things in mind, little higher capacity motors are used for this application. (author)

  16. ICT Solutions for Highly-Customized Water Demand Management Strategies

    Science.gov (United States)

    Giuliani, M.; Cominola, A.; Castelletti, A.; Fraternali, P.; Guardiola, J.; Barba, J.; Pulido-Velazquez, M.; Rizzoli, A. E.

    2016-12-01

    The recent deployment of smart metering networks is opening new opportunities for advancing the design of residential water demand management strategies (WDMS) relying on improved understanding of water consumers' behaviors. Recent applications showed that retrieving information on users' consumption behaviors, along with their explanatory and/or causal factors, is key to spot potential areas where targeting water saving efforts, and to design user-tailored WDMS. In this study, we explore the potential of ICT-based solutions in supporting the design and implementation of highly customized WDMS. On one side, the collection of consumption data at high spatial and temporal resolutions requires big data analytics and machine learning techniques to extract typical consumption features from the metered population of water users. On the other side, ICT solutions and gamifications can be used as effective means for facilitating both users' engagement and the collection of socio-psychographic users' information. This latter allows interpreting and improving the extracted profiles, ultimately supporting the customization of WDMS, such as awareness campaigns or personalized recommendations. Our approach is implemented in the SmartH2O platform and demonstrated in a pilot application in Valencia, Spain. Results show how the analysis of the smart metered consumption data, combined with the information retrieved from an ICT gamified web user portal, successfully identify the typical consumption profiles of the metered users and supports the design of alternative WDMS targeting the different users' profiles.

  17. Removal of Metal Nanoparticles Colloidal Solutions by Water Plants

    Science.gov (United States)

    Olkhovych, Olga; Svietlova, Nataliia; Konotop, Yevheniia; Karaushu, Olena; Hrechishkina, Svitlana

    2016-11-01

    The ability of seven species of aquatic plants ( Elodea canadensis, Najas guadelupensis, Vallisneria spiralis L., Riccia fluitans L., Limnobium laevigatum, Pistia stratiotes L., and Salvinia natans L.) to absorb metal nanoparticles from colloidal solutions was studied. It was established that investigated aquatic plants have a high capacity for removal of metal nanoparticles from aqueous solution (30-100%) which indicates their high phytoremediation potential. Analysis of the water samples content for elements including the mixture of colloidal solutions of metal nanoparticles (Mn, Cu, Zn, Ag + Ag2O) before and after exposure to plants showed no significant differences when using submerged or free-floating hydrophytes so-called pleuston. However, it was found that the presence of submerged hydrophytes in aqueous medium ( E. canadensis, N. guadelupensis, V. spiralis L., and R. fluitans L.) and significant changes in the content of photosynthetic pigments, unlike free-floating hydrophytes ( L. laevigatum, P. stratiotes L., S. natans L.), had occur. Pleuston possesses higher potential for phytoremediation of contaminated water basins polluted by metal nanoparticles. In terms of removal of nanoparticles among studied free-floating hydrophytes, P. stratiotes L. and S. natans L. deserve on special attention.

  18. Water flow and solute transport in floating fen root mats

    Science.gov (United States)

    Stofberg, Sija F.; EATM van der Zee, Sjoerd

    2015-04-01

    be very similar and likely functionally related. Our experimental field data were used for modelling water flow and solute transport in floating fens, using HYDRUS 2D. Fluctuations of surface water and root mat, as well as geometry and unsaturated zone parameters can have a major influence on groundwater fluctuations and the exchange between rain and surface water and the water in the root mats. In combination with the duration of salt pulses in surface water, and sensitivity of fen plants to salinity (Stofberg et al. 2014, submitted), risks for rare plants can be anticipated.

  19. WEB-GIS SOLUTIONS DEVELOPMENT FOR CITIZENS AND WATER COMPANIES

    Directory of Open Access Journals (Sweden)

    M. Şercăianu

    2013-05-01

    Full Text Available This paper describes the development of a web-GIS solution in which urban residents, from Buzau City, could be involved in decision-support process of water companies, in order to reduce water losses, by collecting information directly from citizens. In recent years, reducing material and economic losses, recorded in the entire municipal networks management process has become the main focus of public companies in Romania. Due to problems complexity that arise in collecting information from citizens and issues identified in urban areas, more analyzes were required related to web-GIS solutions used in areas such as local government, public utilities, environmental protection or financial management. Another important problem is the poor infrastructure development of spatial databases founded in public companies, and connection to web platforms. Developing the entire communication process between residents and municipal companies has required the use of concept "citizen-sensor" in the entire reporting process. Reported problems are related to water distribution networks with the possibility of covering the entire public utilities infrastructure.

  20. Web-Gis Solutions Development for Citizens and Water Companies

    Science.gov (United States)

    Şercăianu, M.

    2013-05-01

    This paper describes the development of a web-GIS solution in which urban residents, from Buzau City, could be involved in decision-support process of water companies, in order to reduce water losses, by collecting information directly from citizens. In recent years, reducing material and economic losses, recorded in the entire municipal networks management process has become the main focus of public companies in Romania. Due to problems complexity that arise in collecting information from citizens and issues identified in urban areas, more analyzes were required related to web-GIS solutions used in areas such as local government, public utilities, environmental protection or financial management. Another important problem is the poor infrastructure development of spatial databases founded in public companies, and connection to web platforms. Developing the entire communication process between residents and municipal companies has required the use of concept "citizen-sensor" in the entire reporting process. Reported problems are related to water distribution networks with the possibility of covering the entire public utilities infrastructure.

  1. Solution Thermodynamics of Lysine Clonixinate in Some Ethanol + Water Mixtures

    OpenAIRE

    Delgado, Daniel R.; Martínez, Fleming; Gutiérrez, Rahumir A.

    2012-01-01

    The solubility of lysine clonixinate (LysClon) in several ethanol + water mixtures was determined at 293.15 to 313.15 K. The thermodynamic functions, Gibbs energy, enthalpy, and entropy of solution and of mixing were obtained from these solubility data by using the van’t Hoff and Gibbs equations. In general this drug exhibit good solubility and the greatest value was obtained in the mixture 0.60 in mass fraction of ethanol. A non-linear enthalpy–entropy relationship was observed from ...

  2. Orientational order and dynamics of water in bulk and in aqueous solutions of uranyl ions

    International Nuclear Information System (INIS)

    Chopra, Manish; Choudhury, Niharendu

    2014-01-01

    Molecular dynamics simulations in canonical ensemble of aqueous solutions of uranyl nitrate and bulk water at ambient condition have been carried out to investigate orientational order and dynamics of water. The orientational distributions of water around a central water molecule in bulk water and around a uranyl ion in an aqueous uranyl solution have been calculated. Orientational dynamics of water in bulk and in aqueous uranyl nitrate solution have also been analysed. (author)

  3. Molecular dynamics simulations of lysozyme in water/sugar solutions

    Energy Technology Data Exchange (ETDEWEB)

    Lerbret, A. [Department of Food Science, Cornell University, 101 Stocking Hall, Ithaca, NY 14853 (United States); Affouard, F. [Laboratoire de Dynamique et Structure des Materiaux Moleculaires, UMR CNRS 8024, Universite Lille I, 59655 Villeneuve d' Ascq Cedex (France)], E-mail: frederic.affouard@univ-lille1.fr; Bordat, P. [Laboratoire de Chimie Theorique et de Physico-Chimie Moleculaire, UMR 5624, Universite de Pau et des Pays de l' Adour, 64000 Pau (France); Hedoux, A.; Guinet, Y.; Descamps, M. [Laboratoire de Dynamique et Structure des Materiaux Moleculaires, UMR CNRS 8024, Universite Lille I, 59655 Villeneuve d' Ascq Cedex (France)

    2008-04-18

    Structural and dynamical properties of the solvent at the protein/solvent interface have been investigated by molecular dynamics simulations of lysozyme in trehalose, maltose and sucrose solutions. Results are discussed in the framework of the bioprotection phenomena. The analysis of the relative concentration of water oxygen atoms around lysozyme suggests that lysozyme is preferentially hydrated. When comparing the three sugars, trehalose is seen more excluded than maltose and sucrose. The preferential exclusion of sugars from the protein surface induces some differences in the behavior of trehalose and maltose, particularly at 50 and 60 wt% concentrations, that are not observed experimentally in binary sugar/mixtures. The dynamical slowing down of the solvent is suggested to mainly arise from the homogeneity of the water/sugar matrices controlled by the percolation of the sugar hydrogen bonds networks. Furthermore, lysozyme strongly increases relaxation times of solvent molecules at the protein/solvent interface.

  4. High sensitivity pyrogen testing in water and dialysis solutions.

    Science.gov (United States)

    Daneshian, Mardas; Wendel, Albrecht; Hartung, Thomas; von Aulock, Sonja

    2008-07-20

    The dialysis patient is confronted with hundreds of litres of dialysis solution per week, which pass the natural protective barriers of the body and are brought into contact with the tissue directly in the case of peritoneal dialysis or indirectly in the case of renal dialysis (hemodialysis). The components can be tested for living specimens or dead pyrogenic (fever-inducing) contaminations. The former is usually detected by cultivation and the latter by the endotoxin-specific Limulus Amoebocyte Lysate Assay (LAL). However, the LAL assay does not reflect the response of the human immune system to the wide variety of possible pyrogenic contaminations in dialysis fluids. Furthermore, the test is limited in its sensitivity to detect extremely low concentrations of pyrogens, which in their sum result in chronic pathologies in dialysis patients. The In vitro Pyrogen Test (IPT) employs human whole blood to detect the spectrum of pyrogens to which humans respond by measuring the release of the endogenous fever mediator interleukin-1beta. Spike recovery checks exclude interference. The test has been validated in an international study for pyrogen detection in injectable solutions. In this study we adapted the IPT to the testing of dialysis solutions. Preincubation of 50 ml spiked samples with albumin-coated microspheres enhanced the sensitivity of the assay to detect contaminations down to 0.1 pg/ml LPS or 0.001 EU/ml in water or saline and allowed pyrogen detection in dialysis concentrates or final working solutions. This method offers high sensitivity detection of human-relevant pyrogens in dialysis solutions and components.

  5. Influence of Water and Mineral Oil on the Leaks in Satellite Motor Commutation Unit Clearances

    Directory of Open Access Journals (Sweden)

    Śliwiński Paweł

    2017-09-01

    Full Text Available The article describes the flow rates of mineral oil and water flowing, as working media, through the commutation unit of a hydraulic satellite motor. It is demonstrated that geometrical dimensions of commutation unit clearances change as a function of the machine shaft rotation angle. Methods for measuring the rate of this flow and the pressure in the working chamber are presented. The results of pressure measurements in the working chamber during the transition from the filling cycle to the emptying cycle are included. The pressure in the motor’s working chamber changes linearly as a function of the shaft rotation angle, which has a significant effect on the leakage in the commutation unit clearances. The paper presents new mathematical formulas in the form: Q=f(Δpγ to calculate the flow rate of water and mineral oil in the commutation unit clearances. The γ factor is described as a function of fluid viscosity and clearance length (the motor shaft rotation angle. The coefficients used in these formulas were determined based on the results of laboratory tests of a motor supplied with water and mineral oil.

  6. Water, gas and solute movement through argillaceous media

    International Nuclear Information System (INIS)

    Horseman, S.T.; Higgo, J.J.W.; Alexander, J.; Harrington, J.F.

    1996-01-01

    This report was commissioned by a consortium of companies and organisations with a common concern: the capacity of clay-rich media to act as barriers to the movement of radionuclides. Since the migration of such contaminants occurs primarily in aqueous solutions, considerable emphasis is placed on the motion of groundwater in the subsurface environment and on the advective and diffusive transport of solutes within this water. This report examines clay systems at a very wide range of scales, from the molecular-scale interactions between water molecules and clay surfaces, through to large-scale processes such as the movement of fluids in sedimentary basins. Its goal is to study the links between the colloidal interactions between clay mineral particles, the mechanical responses of the system and the movement of fluids. The Darcy's or Fick's laws were adopted as a basis for the phenomenological mass transfer calculations, and a very idealized porous medium having clearly identifiable characteristics and properties was considered to replace the inordinately complex and highly-variable geologic medium. It is also assumed that geological processes, other than transport processes, either cease to operate over the time-scale of interest or can have no secondary effect on mass transport. (J.S.). 737 refs., 25 figs., 4 tabs., 2 appends

  7. A parallel solution-adaptive scheme for predicting multi-phase core flows in solid propellant rocket motors

    International Nuclear Information System (INIS)

    Sachdev, J.S.; Groth, C.P.T.; Gottlieb, J.J.

    2003-01-01

    The development of a parallel adaptive mesh refinement (AMR) scheme is described for solving the governing equations for multi-phase (gas-particle) core flows in solid propellant rocket motors (SRM). An Eulerian formulation is used to described the coupled motion between the gas and particle phases. A cell-centred upwind finite-volume discretization and the use of limited solution reconstruction, Riemann solver based flux functions for the gas and particle phases, and explicit multi-stage time-stepping allows for high solution accuracy and computational robustness. A Riemann problem is formulated for prescribing boundary data at the burning surface. Efficient and scalable parallel implementations are achieved with domain decomposition on distributed memory multiprocessor architectures. Numerical results are described to demonstrate the capabilities of the approach for predicting SRM core flows. (author)

  8. WaterNet: The NASA water cycle solutions network - Danubian regional applications

    International Nuclear Information System (INIS)

    Matthews, Dave; Brilly, Mitja; Kobold, Mira; Zagar, Mark; Houser, Paul

    2008-01-01

    WaterNet is a new international network of researchers, stakeholders, and end-users of remote sensing tools that will benefit the water resources management community. This paper provides an overview and it discusses the concept of solutions networks focusing on the WaterNet. It invites Danubian research and applications teams to join our WaterNet network. The NASA Water cycle Solutions Network's goal is to improve and optimize the sustained ability of water cycle researchers, stakeholders, organizations and networks to interact, identify, harness, and extend NASA research results to augment decision support tools and meet national needs. Our team will develop WaterNet by engaging relevant NASA water cycle research resources and community-of-practice organizations, to develop what we term an 'actionable database' that can be used to communicate and connect NASA Water cycle research Results (NWRs) towards the improvement of water-related Decision Support Tools (DSTs). Recognizing that the European Commission and European Space Agency have also developed many related Water Research products (EWRs), we seek to learn about these and network with the EU teams to include their information in the WaterNet actionable data base and Community of Practice. WaterNet will then develop strategies to connect researchers and decision-makers via innovative communication strategies, improved user access to NASA and EU - Danubian resources, improved water cycle research community appreciation for user requirements, improved policymaker, management and stakeholder knowledge of research and application products, and improved identification of pathways for progress. Finally, WaterNet will develop relevant benchmarking and metrics, to understand the network's characteristics, to optimize its performance, and to establish sustainability. This paper provides examples of several NASA products based on remote sensing and land data assimilation systems that integrate remotely sensed and in

  9. Electrotechnics - AC motors. Asynchronous and brush-less motors - Lecture and exercises with solutions; Electrotechnique - Moteurs a courant alternatif. Moteurs asynchrones et brushless - Cours et problemes resolus

    Energy Technology Data Exchange (ETDEWEB)

    Jacob, D.

    2005-07-01

    This book proposes a presentation of AC electric motors essentially based on physics and technology. Its originality consists in avoiding to use mathematical formulations (like Park's transformation). The modeling retained, which only uses magnetic momentum, magnetic fields and reluctance concepts, leads simply and naturally to the vectorial control principle. The book develops some lecture elements which includes some topics rarely considered like the dimensioning of an asynchronous motor or of a single-phase brush-less motor. Experimental results illustrate the physical phenomena described and many original problems are resolved and commented at the end of each chapter. Content: signals and systems in electrotechnics, torque and rotating magnetic fields generation, asynchronous machine in permanent regime, speed variation of the asynchronous motor, special asynchronous motors, synchronous machine in permanent regime, brush-less motor, note about step motors, note about inverters, index. (J.S.)

  10. Deep subsurface drip irrigation using coal-bed sodic water: part I. water and solute movement

    Science.gov (United States)

    Bern, Carleton R.; Breit, George N.; Healy, Richard W.; Zupancic, John W.; Hammack, Richard

    2013-01-01

    Water co-produced with coal-bed methane (CBM) in the semi-arid Powder River Basin of Wyoming and Montana commonly has relatively low salinity and high sodium adsorption ratios that can degrade soil permeability where used for irrigation. Nevertheless, a desire to derive beneficial use from the water and a need to dispose of large volumes of it have motivated the design of a deep subsurface drip irrigation (SDI) system capable of utilizing that water. Drip tubing is buried 92 cm deep and irrigates at a relatively constant rate year-round, while evapotranspiration by the alfalfa and grass crops grown is seasonal. We use field data from two sites and computer simulations of unsaturated flow to understand water and solute movements in the SDI fields. Combined irrigation and precipitation exceed potential evapotranspiration by 300-480 mm annually. Initially, excess water contributes to increased storage in the unsaturated zone, and then drainage causes cyclical rises in the water table beneath the fields. Native chloride and nitrate below 200 cm depth are leached by the drainage. Some CBM water moves upward from the drip tubing, drawn by drier conditions above. Chloride from CBM water accumulates there as root uptake removes the water. Year over year accumulations indicated by computer simulations illustrate that infiltration of precipitation water from the surface only partially leaches such accumulations away. Field data show that 7% and 27% of added chloride has accumulated above the drip tubing in an alfalfa and grass field, respectively, following 6 years of irrigation. Maximum chloride concentrations in the alfalfa field are around 45 cm depth but reach the surface in parts of the grass field, illustrating differences driven by crop physiology. Deep SDI offers a means of utilizing marginal quality irrigation waters and managing the accumulation of their associated solutes in the crop rooting zone.

  11. A solution to water vapor in the National Transonic Facility

    Science.gov (United States)

    Gloss, Blair B.; Bruce, Robert A.

    1989-01-01

    As cryogenic wind tunnels are utilized, problems associated with the low temperature environment are being discovered and solved. Recently, water vapor contamination was discovered in the National Transonic Facility, and the source was shown to be the internal insulation which is a closed-cell polyisocyanurate foam. After an extensive study of the absorptivity characteristics of the NTF thermal insulation, the most practical solution to the problem was shown to be the maintaining of a dry environment in the circuit at all times. Utilizing a high aspect ratio transport model, it was shown that the moisture contamination effects on the supercritical wing pressure distributions were within the accuracy of setting test conditions and as such were considered negligible for this model.

  12. An Integrated Water Treatment Technology Solution for Sustainable Water Resource Management in the Marcellus Shale

    Energy Technology Data Exchange (ETDEWEB)

    Matthew Bruff; Ned Godshall; Karen Evans

    2011-04-30

    This Final Scientific/ Technical Report submitted with respect to Project DE-FE0000833 titled 'An Integrated Water Treatment Technology Solution for Sustainable Water Resource Management in the Marcellus Shale' in support of final reporting requirements. This final report contains a compilation of previous reports with the most current data in order to produce one final complete document. The goal of this research was to provide an integrated approach aimed at addressing the increasing water resource challenges between natural gas production and other water stakeholders in shale gas basins. The objective was to demonstrate that the AltelaRain{reg_sign} technology could be successfully deployed in the Marcellus Shale Basin to treat frac flow-back water. That objective has been successfully met.

  13. Roles of surface water areas for water and solute cycle in Hanoi city, Viet Nam

    Science.gov (United States)

    Hayashi, Takeshi; Kuroda, Keisuke; Do Thuan, An; Tran Thi Viet, Nga; Takizawa, Satoshi

    2013-04-01

    Hanoi city, the capital of Viet Nam, has developed beside the Red river. Recent rapid urbanization of this city has reduced a large number of natural water areas such as lakes, ponds and canals not only in the central area but the suburban area. Contrary, the urbanization has increased artificial water areas such as pond for fish cultivation and landscaping. On the other hand, the urbanization has induced the inflow of waste water from households and various kinds of factories to these water areas because of delay of sewerage system development. Inflow of the waste water has induced eutrophication and pollution of these water areas. Also, there is a possibility of groundwater pollution by infiltration of polluted surface water. However, the role of these water areas for water cycle and solute transport is not clarified. Therefore, this study focuses on the interaction between surface water areas and groundwater in Hanoi city to evaluate appropriate land development and groundwater resource management. We are carrying out three approaches: a) understanding of geochemical characteristics of surface water and groundwater, b) monitoring of water levels of pond and groundwater, c) sampling of soil and pond sediment. Correlation between d18O and dD of precipitation (after GNIP), the Red River (after GNIR) and the water samples of this study showed that the groundwater is composed of precipitation, the Red River and surface water that has evaporation process. Contribution of the surface water with evaporation process was widely found in the study area. As for groundwater monitoring, the Holocene aquifers at two sites were in unconfined condition in dry season and the groundwater levels in the aquifer continued to increase through rainy season. The results of isotopic analysis and groundwater level monitoring showed that the surface water areas are one of the major groundwater sources. On the other hand, concentrations of dissolved Arsenic (filtered by 0.45um) in the pore

  14. Glass-water interphase reactivity with calcium rich solutions

    International Nuclear Information System (INIS)

    Chave, T.; Frugier, P.; Gin, S.; Chave, T.; Ayral, A.

    2011-01-01

    The effect of calcium on synthetic glass alteration mechanisms has been studied. It is known that the higher the calcium content in the glass, the higher the forward rate. However, in a confined medium reaching apparent saturation state and a pH (90 degrees C) around 9, synthetic calcium-bearing glasses are those with the lowest alteration rates. This work brings new and fundamental evidence toward understanding the alteration mechanisms: the rate-decreasing effect of calcium exists even if the calcium comes from the solution. Calcium from solution reacts with silica network in the hydrated layer at the glass surface. The calcium effect on the alteration kinetics is explained by the condensation of a passivating reactive interphase (PRI) whose passivating properties are strongly enhanced when calcium participates in its construction. These experiments provide new evidence of the role of condensation mechanisms in glass alteration. This better understanding of the calcium effect on glass long-term behavior will be useful both for improving glass formulations and for understanding the influence of the water composition. (authors)

  15. Fluid transport with time on peritoneal dialysis: the contribution of free water transport and solute coupled water transport

    NARCIS (Netherlands)

    Coester, Annemieke M.; Smit, Watske; Struijk, Dirk G.; Krediet, Raymond T.

    2009-01-01

    Ultrafiltration in peritoneal dialysis occurs through endothelial water channels (free water transport) and together with solutes across small pores: solute coupled water transport. A review is given of cross-sectional studies and on the results of longitudinal follow-up

  16. Separation of motor oils, oily wastes and hydrocarbons from contaminated water by sorption on chrome shavings.

    Science.gov (United States)

    Gammoun, A; Tahiri, S; Albizane, A; Azzi, M; Moros, J; Garrigues, S; de la Guardia, M

    2007-06-25

    In this paper, the ability of chrome shavings to remove motor oils, oily wastes and hydrocarbons from water has been studied. To determine amount of hydrocarbons sorbed on tanned wastes, a FT-NIR methodology was used and a multivariate calibration based on partial least squares (PLS) was employed for data treatment. The light density, porous tanned waste granules float on the surface of water and remove hydrocarbons and oil films. Wastes fibers from tannery industry have high sorption capacity. These tanned solid wastes are capable of absorbing many times their weight in oil or hydrocarbons (6.5-7.6g of oil and 6.3g of hydrocarbons per gram of chrome shavings). The removal efficiency of the pollutants from water is complete. The sorption of pollutants is a quasi-instantaneous process.

  17. Water flow and solute transport using environmental isotopes and modeling

    International Nuclear Information System (INIS)

    Hussein, M.F.

    2001-01-01

    The deep unsaturated zone may be a useful hydrological archive in desert environments characterized by scant or sporadic rainfall and slow percolation of rainwater over decades or even centuries. This moisture archive provides a useful way to distinguish the net downward flow of recharge water, whereas the isotopic composition and concentration of the conservative solutes of the preserved moisture could be used to reconstruct the history of recharge under the prevailing deficient water balance. The major advantage of such coupled approach is to obtain independent estimates of groundwater recharge rates which are normally difficult to evaluate using the hydrological methods applied in the temperate zones. The study was conducted in the Shiekh-Zoweid/Raffa area in the northeastern coastal strip of Sinai Peninsula. Bore-holes were dry-drilled in a line perpendicular to the sea shoreline (using an 8-inch diameter hand-operated rotary rig) for the unsaturated sediment collection from successive 0.5m thick layers down to a depth of 20m. Samples were investigated for the moisture contents and the chemical and isotope composition of this moisture was determined. Physical parameters were also assessed including porosity and volumetric moisture content. Chloride mass-balance was used to calculate recharge rates through the unsaturated zone by predicting the position of the 1963-Tritium peak in the unsaturated column. Analysis of moisture, chloride and deuterium profiles showed three principle peaks (along with minor ones) in Karafin site indicating few major recharge events that have taken place during the last few decades. Adjustment of these episodes has also been attempted using two historical major rainfall events (known from nearby meteorological stations). Application of the methodology in water resources management in arid regions is discussed. (author)

  18. Hard paths, soft paths or no paths? Cross-cultural perceptions of water solutions

    Science.gov (United States)

    Wutich, A.; White, A. C.; White, D. D.; Larson, K. L.; Brewis, A.; Roberts, C.

    2014-01-01

    In this study, we examine how development status and water scarcity shape people's perceptions of "hard path" and "soft path" water solutions. Based on ethnographic research conducted in four semi-rural/peri-urban sites (in Bolivia, Fiji, New Zealand, and the US), we use content analysis to conduct statistical and thematic comparisons of interview data. Our results indicate clear differences associated with development status and, to a lesser extent, water scarcity. People in the two less developed sites were more likely to suggest hard path solutions, less likely to suggest soft path solutions, and more likely to see no path to solutions than people in the more developed sites. Thematically, people in the two less developed sites envisioned solutions that involve small-scale water infrastructure and decentralized, community-based solutions, while people in the more developed sites envisioned solutions that involve large-scale infrastructure and centralized, regulatory water solutions. People in the two water-scarce sites were less likely to suggest soft path solutions and more likely to see no path to solutions (but no more likely to suggest hard path solutions) than people in the water-rich sites. Thematically, people in the two water-rich sites seemed to perceive a wider array of unrealized potential soft path solutions than those in the water-scarce sites. On balance, our findings are encouraging in that they indicate that people are receptive to soft path solutions in a range of sites, even those with limited financial or water resources. Our research points to the need for more studies that investigate the social feasibility of soft path water solutions, particularly in sites with significant financial and natural resource constraints.

  19. Ab Initio Liquid Water Dynamics in Aqueous TMAO Solution.

    Science.gov (United States)

    Usui, Kota; Hunger, Johannes; Sulpizi, Marialore; Ohto, Tatsuhiko; Bonn, Mischa; Nagata, Yuki

    2015-08-20

    Ab initio molecular dynamics (AIMD) simulations in trimethylamine N-oxide (TMAO)-D2O solution are employed to elucidate the effects of TMAO on the reorientational dynamics of D2O molecules. By decomposing the O-D groups of the D2O molecules into specific subensembles, we reveal that water reorientational dynamics are retarded considerably in the vicinity of the hydrophilic TMAO oxygen (O(TMAO)) atom, due to the O-D···O(TMAO) hydrogen-bond. We find that this reorientational motion is governed by two distinct mechanisms: The O-D group rotates (1) after breaking the O-D···O(TMAO) hydrogen-bond, or (2) together with the TMAO molecule while keeping this hydrogen-bond intact. While the orientational slow-down is prominent in the AIMD simulation, simulations based on force field models exhibit much faster dynamics. The simulated angle-resolved radial distribution functions illustrate that the O-D···O(TMAO) hydrogen-bond has a strong directionality through the sp(3) orbital configuration in the AIMD simulation, and this directionality is not properly accounted for in the force field simulation. These results imply that care must be taken when modeling negatively charged oxygen atoms as single point charges; force field models may not adequately describe the hydration configuration and dynamics.

  20. The Antioxidant Activity of Quercetin in Water Solution

    Directory of Open Access Journals (Sweden)

    Riccardo Amorati

    2017-06-01

    Full Text Available Abstract: Despite its importance, little is known about the absolute performance and the mechanism for quercetin’s antioxidant activity in water solution. We have investigated this aspect by combining differential oxygen-uptake kinetic measurements and B3LYP/6311+g (d,p calculations. At pH = 2.1 (30 °C, quercetin had modest activity (kinh = 4.0 × 103 M−1 s−1, superimposable to catechol. On raising the pH to 7.4, reactivity was boosted 40-fold, trapping two peroxyl radicals in the chromen-4-one core and two in the catechol with kinh of 1.6 × 105 and 7.0 × 104 M−1 s−1. Reaction occurs from the equilibrating mono-anions in positions 4′ and 7 and involves firstly the OH in position 3, having bond dissociation enthalpies of 75.0 and 78.7 kcal/mol, respectively, for the two anions. Reaction proceeds by a combination of proton-coupled electron-transfer mechanisms: electron–proton transfer (EPT and sequential proton loss electron transfer (SPLET. Our results help rationalize quercetin’s reactivity with peroxyl radicals and its importance under biomimetic settings, to act as a nutritional antioxidant.

  1. Highly Water-Soluble Magnetic Nanoparticles as Novel Draw Solutes in Forward Osmosis for Water Reuse

    KAUST Repository

    Ling, Ming Ming

    2010-06-16

    Highly hydrophilic magnetic nanoparticles have been molecularly designed. For the first time, the application of highly water-soluble magnetic nanoparticles as novel draw solutes in forward osmosis (FO) was systematically investigated. Magnetic nanoparticles functionalized by various groups were synthesized to explore the correlation between the surface chemistry of magnetic nanoparticles and the achieved osmolality. We verified that magnetic nanoparticles capped with polyacrylic acid can yield the highest driving force and subsequently highest water flux among others. The used magnetic nanoparticles can be captured by the magnetic field and recycled back into the stream as draw solutes in the FO process. In addition, magnetic nanoparticles of different diameters were also synthesized to study the effect of particles size on FO performance. We demonstrate that the engineering of surface hydrophilicity and magnetic nanoparticle size is crucial in the application of nanoparticles as draw solutes in FO. It is believed that magnetic nanoparticles will soon be extensively used in this area. © 2010 American Chemical Society.

  2. Advanced development and operating experience with a canned motor pump under pressurized water reactor conditions

    International Nuclear Information System (INIS)

    Dittmer, H.; Reymann, A.; Seibig, B.; Reinecker, H.

    1988-01-01

    At the research reactor FRG-2, Geesthacht, an irradiation device is in operation for testing defective light-water-reactor (LWR) test fuel rods under pressurized water reactor conditions (320 0 C, 160 bar). The requirements to the canned motor pump for cooling water circulation: medium: Demineralized water, operating temperature 320 0 C, operating pressure 155 bar, radiation field of the reactor, integration in the irradiation capsule, helium leak rate -6 mbar.dm 3 .s -1 , minimum working life 3000 hours, were high and caused difficulties in the acquisition of this component. First test runs with supplied pumps showed that the desired working life could not be achieved. The results of the development steps, the test runs, and the performance in service show that for our range of applications, the best combination of materials for the radial bearings is silicon-infiltrated SiC (8% free Si) against the same material. These bearings allowed a good working life for the pump to be achieved. (orig./GL) [de

  3. Failure analysis of the stud bolt of a canned motor pump of heavy water plant, Talcher

    International Nuclear Information System (INIS)

    Kumar, Sunil; Sethumadhavan, V.; Sah, D.N.; Sivaramakrishnan, K.S.; Kain, Vivekanand; Gadiyar, H.S.

    1990-01-01

    Detailed investigations have been carried out on the failed stud bolts (made of DIN 1.4021 X 20Cr 13) of a canned motor pump of Heavy Water Plant, Talcher, using metallographic, microhardness testing, scanning electron microscopy and electron probe micro-analysis(EPMA) techniques. The studs had failed in a brittle manner in the mid-length portion. The origin of the fracture has been identified to be a corroded region on the stud surface. Branching cracks propagating through silicon rich inclusions have been noted. Two types of inclusions, one containing Mn and S and other containing S, Mn and O 2 have been found in the material. Clusters of large and small inclusions of the above types have been found near the origin of the fracture. It has been concluded that the fracture was caused by corrosion fatigue, initiating at the cluster of inclusions present on the surface of the stud bolts. (author). 7 refs., 5 figs

  4. Formation of H2O2 at UV-photolysis of water solutions of phenol

    International Nuclear Information System (INIS)

    Guliyeva, U.A.; Gurbanov, M.A.; Mahmudov, H.M.

    2013-01-01

    Non-traditional methods, based on application of ionizing and UV-radiation widely used for cleaning of water solutions from toxic substances, including phenols. These methods have simultaneously effect including of disinfection and chemical cleaning of water solutions from various industrial processes

  5. New methods For Modeling Transport Of Water And Solutes In Soils

    DEFF Research Database (Denmark)

    Møldrup, Per

    Recent models for water and solute transport in unsaturated soils have been mechanistically based but numerically very involved. This dissertation concerns the development of mechanistically-based but numerically simple models for calculating and analyzing transport of water and solutes in soil...

  6. The solution to avoid protection fuses' failure of the driving motor of the turbine-generator set during its startup in Daya Bay Nuclear Power Station

    International Nuclear Information System (INIS)

    Chen Jisheng

    2005-01-01

    Based on a detailed analysis of the inter-relationship in the current, voltage, electromagnetic torque and ratio of the difference between the speed of rotor and the speed of rotary magnetic field to the later in the motor, the root cause was point out, which leads to the protection fuses' failure of the motor in the starting stage, which drives the turbine-generator set to rotate at low speed before its startup. Two solutions to avoid the situation are proposed, too. (authors)

  7. Evaluation of Polyuria: The Roles of Solute Loading and Water Diuresis.

    Science.gov (United States)

    Bhasin, Bhavna; Velez, Juan Carlos Q

    2016-03-01

    Polyuria, defined as daily urine output in excess of 3.0 to 3.5L/d, can occur due to solute or water diuresis. Solute-induced polyuria can be seen in hospitalized patients after a high solute load from exogenous protein administration or following relief of urinary obstruction. Similar clinical scenarios are rarely encountered in the outpatient setting. We describe a case of polyuria due to high solute ingestion and excessive water intake leading to a mixed picture of solute and water diuresis. Restriction of the daily solute load and water intake resulted in complete resolution of polyuria. Determination of the daily excreted urinary osmoles may yield important clues to the cause of polyuria and should be included in the routine workup of polyuria. Copyright © 2016 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.

  8. Solution of tasks concerning protection of underground waters and environment

    International Nuclear Information System (INIS)

    Dubinchuk, V.T.; Polyakov, V.A.

    1988-01-01

    Use of environment isotopes and indicators in solving problems concerning protection of underground waters and environment is discussed. The applied methods permit to study dynamics of underground waters and to estimate risk of their contamination; to follow the surface and underground waters interrelations using data on infiltration recharge estimation etc. Complex nuclear-geophysical and isotope studies may be applied to detect hindered water exchange zones where liquid industrial waste disposals could be placed with minimum damage to environment. 48 refs.; 74 figs.; 22 tabs

  9. Is Storage a Solution to End Water Shortage?

    Science.gov (United States)

    Narayanan, M.

    2009-12-01

    Water shortage is a problem of supply and demand. Some authors refer to it as Water Scarcity. The author has discussed this in his previous presentation at the 2008 AGU International Conference. Part of it is reproduced here for purposes of clarification. It is important to recognize that water is essential for the survival of all life on earth. Many water-rich states have thought of water conservation as an art that is practiced mainly in the arid states. But one has to recite the famous quote: “You will never miss water till the well runs dry.” Researchers have also concluded that quantity deficiency experienced by groundwater supplies are affecting many communities around the world. Furthermore federal regulations pertaining to the quality of potable or drinking water have become more stringent (Narayanan, 2008). One must observe that water conservation schemes and efficient utilization practices also benefit the environment to a large extent. These water conservation practicies indeed have a short payback period althought it may seem that there is a heavy initial investment is required. Research scientists have studied MARR (Mean Annual River Runoff) pattern over the years and have arrived at some significant conclusions. Vörsömarty and other scientists have indicated that water scarcity exists when the demand to supply ratio exceeds the number 0.4. (Vörsömarty, 2005). Furthermore other researchers claim to have documented a six-fold increase in water use in the United States during the last century. It is interesting to note that the population of the United States has hardly doubled during the last century. This obviously, is indicative of higher living standards. Nevertheless, it also emphasizes an urgent need for establishing a strong, sound, sensible and sustainable management program for utilizing the available water supplies efficiently (Narayanan, 2008). Author of the 1998 book, Last Oasis: Facing Water Scarcity, Dr. Sandra Postel predicts big

  10. Prolonged river water pollution due to variable-density flow and solute transport in the riverbed

    Science.gov (United States)

    Jin, Guangqiu; Tang, Hongwu; Li, Ling; Barry, D. A.

    2015-04-01

    A laboratory experiment and numerical modeling were used to examine effects of density gradients on hyporheic flow and solute transport under the condition of a solute pulse input to a river with regular bed forms. Relatively low-density gradients due to an initial salt pulse concentration of 1.55 kg m-3 applied in the experiment were found to modulate significantly the pore-water flow and solute transport in the riverbed. Such density gradients increased downward flow and solute transport in the riverbed by factors up to 1.6. This resulted in a 12.2% increase in the total salt transfer from the water column to the riverbed over the salt pulse period. As the solute pulse passed, the effect of the density gradients reversed, slowing down the release of the solute back to the river water by a factor of 3.7. Numerical modeling indicated that these density effects intensified as salt concentrations in the water column increased. Simulations further showed that the density gradients might even lead to unstable flow and result in solute fingers in the bed of large bed forms. The slow release of solute from the bed back to the river led to a long tail of solute concentration in the river water. These findings have implications for assessment of impact of pollution events on river systems, in particular, long-term effects on both the river water and riverbed due to the hyporheic exchange.

  11. Water Soluble Vitamins Enhance the Growth of Microorganisms in Peripheral Parenteral Nutrition Solutions.

    Science.gov (United States)

    Omotani, Sachiko; Tani, Katsuji; Nagai, Katsuhito; Hatsuda, Yasutoshi; Mukai, Junji; Myotoku, Michiaki

    2017-01-01

    Peripheral parenteral nutrition (PPN) solutions contain amino acids, glucose, and electrolytes, with or without some water soluble vitamins. Peripheral venous catheters are one of the causes of catheter related blood stream infection (CRBSI), which requires infection control. In Japan, PPN solutions have rarely been prepared under aseptic conditions. However, in recent years, the necessity of adding vitamins to infusions has been reported. Therefore, we investigated the effects of water soluble vitamins on growth of microorganisms in PPN solutions. AMINOFLUID ® (AF), BFLUID ® (BF), PARESAFE ® (PS) and PAREPLUS ® (PP) PPN solutions were used. Water soluble vitamins contained in PP were also used. Causative microorganisms of CRBSI were used. Staphylococcus epidermidis decreased after 24 hours or 48 hours in all solutions. On the other hand, Escherichia coli , Serratia marcescens , Pseudomonas aeruginosa, Staphylococcus aureus and Candida albicans increased, especially in PP. When each water soluble vitamin was added to BF and PS, growth of S. aureus was greater in solutions that contained nicotinamide than in solutions that contained other vitamins. As for C. albicans , they grew in all test solutions. C. albicans grew especially well in solutions that contained biotin. When commercial amino acids and glucose solutions with electrolytes are administered, in particular those containing multivitamins or water soluble vitamins, efforts to control infection must be taken to prevent proliferation of microorganisms.

  12. Water chemistry at RBMK plants: Problems and solutions

    International Nuclear Information System (INIS)

    Mamet, V.; Yurmanov, V.

    2002-01-01

    After around 15 years of operation RBMK-1000 units undergo a major refit, which includes safety system upgrading, fuel tube replacement, etc. The above upgrading has created problems for water chemistry. In particular, in late 80's in-core insertion time of the portion of control rods was reduced 10-fold thanks to a transfer from water to filming cooling of scram channels. Scram channels are cooled with inner surface water film cooling and nitrogen is injected into heads via special pipelines. Such cooling system modernization ensures fast insertion of absorber rods. The above upgrade intensified nitric acid radiolytic generation in water coolant and pH 25 value shift to acid conditions (up to 4.5). The results of corrosion tests in such conditions proved the necessity to improve water chemistry to ensure corrosion protection of scram/control rod and circuit components, especially those made out of aluminium alloy. Since 1990 the new revision of the RBMK-1000 water chemistry standard specified the new normal operational limit and action levels for possible temporary deviations of pH 25 value. RBMK plant specific measures were implemented at RBMK plants to meet the above requirements of the 1990 revision of the RBMK-1000 water chemistry standard. Clean-up systems of the above circuit were upgraded to ensure intensive absorption of nitric acid from water and pH 25 maintenance in a slightly acid area. (authors)

  13. Overcoming water challenges through nature-based solutions

    NARCIS (Netherlands)

    Boelee, Eline; Janse, Jan; Gal, Le Antoine; Kok, Marcel; Alkemade, Rob; Ligtvoet, Willem

    2017-01-01

    Freshwater is a key resource and medium for various economic sectors and domestic purposes but its use is often at the expense of natural ecosystems. Water management must change to deal with urgent issues and protect aquatic ecosystems and their services, while addressing the demand for water from

  14. The end of abundance. Economic solutions to water scarcity

    NARCIS (Netherlands)

    Zetland, D.J.

    2011-01-01

    In a past of abundance, we had clean water to meet our demands for showers, pools, farms and rivers. Our laws and customs did not need to regulate or ration demand. Over time, our demand has grown, and scarcity has replaced abundance. We don't have as much clean water as we want. We can respond to

  15. Simultaneous transport of water and solutes under transient ...

    Indian Academy of Sciences (India)

    trol salt movement from the soil surface through the root zone to the ground water and stream flows. .... found from the slope of early-time plot of q∞ vs. St. 1/2 and q∞ from the ..... nutrients in the soil water increases, it results in greater total ...

  16. Water chemistry at RBMK plants: Problems and solutions

    Energy Technology Data Exchange (ETDEWEB)

    Mamet, V.; Yurmanov, V. [VNIIAES (Russian Federation)

    2002-07-01

    After around 15 years of operation RBMK-1000 units undergo a major refit, which includes safety system upgrading, fuel tube replacement, etc. The above upgrading has created problems for water chemistry. In particular, in late 80's in-core insertion time of the portion of control rods was reduced 10-fold thanks to a transfer from water to filming cooling of scram channels. Scram channels are cooled with inner surface water film cooling and nitrogen is injected into heads via special pipelines. Such cooling system modernization ensures fast insertion of absorber rods. The above upgrade intensified nitric acid radiolytic generation in water coolant and pH{sub 25} value shift to acid conditions (up to 4.5). The results of corrosion tests in such conditions proved the necessity to improve water chemistry to ensure corrosion protection of scram/control rod and circuit components, especially those made out of aluminium alloy. Since 1990 the new revision of the RBMK-1000 water chemistry standard specified the new normal operational limit and action levels for possible temporary deviations of pH{sub 25} value. RBMK plant specific measures were implemented at RBMK plants to meet the above requirements of the 1990 revision of the RBMK-1000 water chemistry standard. Clean-up systems of the above circuit were upgraded to ensure intensive absorption of nitric acid from water and pH{sub 25} maintenance in a slightly acid area. (authors)

  17. Diet change—a solution to reduce water use?

    International Nuclear Information System (INIS)

    Jalava, M; Kummu, M; Porkka, M; Varis, O; Siebert, S

    2014-01-01

    Water and land resources are under increasing pressure in many parts of the globe. Diet change has been suggested as a measure to contribute to adequate food security for the growing population. This paper assesses the impact of diet change on the blue and green water footprints of food consumption. We first compare the water consumption of the current diets with that of a scenario where dietary guidelines are followed. Then, we assess these footprints by applying four scenarios in which we gradually limit the amount of protein from animal products to 50%, 25%, 12.5% and finally 0% of the total protein intake. We find that the current water use at the global scale would be sufficient to secure a recommended diet and worldwide energy intake. Reducing the animal product contribution in the diet would decrease global green water consumption by 6%, 11%, 15% and 21% within the four applied scenarios, while for blue water, the reductions would be 4%, 6%, 9% and 14%. In Latin America, Europe, Central and Eastern Asia and Sub-Saharan Africa, diet change mainly reduces green water use, while in the Middle East region, North America, Australia and Oceania, both blue and green water footprints decrease considerably. At the same time, in South and Southeast Asia, diet change does not result in decreased water use. Our results show that reducing animal products in the human diet offers the potential to save water resources, up to the amount currently required to feed 1.8 billion additional people globally; however, our results show that the adjustments should be considered on a local level. (letter)

  18. Compatible solutes in lactic acid bacteria subjected to water stress

    NARCIS (Netherlands)

    Kets, E.P.W.

    1997-01-01

    The goal of the research project described in this thesis was to investigate the protective effect of compatible solutes on tactic acid bacteria subjected to drying. Dried preparations of lactic acid bacteria are applied as starter cultures in feed and food industries. Dried starter

  19. Water and Aqueous Solutions: Simple Non-Speculative Model Approach

    Czech Academy of Sciences Publication Activity Database

    Nezbeda, Ivo; Jirsák, Jan

    2011-01-01

    Roč. 13, č. 44 (2011), s. 19689-19703 ISSN 1463-9076 R&D Projects: GA AV ČR IAA400720802; GA AV ČR IAA200760905 Institutional research plan: CEZ:AV0Z40720504 Keywords : molecular modeling of water * separation * perturbation Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 3.573, year: 2011

  20. Nanofiltration: ion exchange system for effective surfactant removal from water solutions

    Directory of Open Access Journals (Sweden)

    I. Kowalska

    2014-12-01

    Full Text Available A system combining nanofiltration and ion exchange for highly effective separation of anionic surfactant from water solutions was proposed. The subjects of the study were nanofiltration polyethersulfone membranes and ion-exchange resins differing in type and structure. The quality of the treated solution was affected by numerous parameters, such as quality of the feed solution, membrane cut-off, resin type, dose and the solution contact time with the resin. A properly designed purification system made it possible to reduce the concentration of anionic surfactant below 1 mg L-1 from feed solutions containing surfactant in concentrations above the CMC value.

  1. Communication: Modeling of concentration dependent water diffusivity in ionic solutions: Role of intermolecular charge transfer

    Energy Technology Data Exchange (ETDEWEB)

    Yao, Yi; Berkowitz, Max L., E-mail: maxb@unc.edu, E-mail: ykanai@unc.edu; Kanai, Yosuke, E-mail: maxb@unc.edu, E-mail: ykanai@unc.edu [Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599 (United States)

    2015-12-28

    The translational diffusivity of water in solutions of alkali halide salts depends on the identity of ions, exhibiting dramatically different behavior even in solutions of similar salts of NaCl and KCl. The water diffusion coefficient decreases as the salt concentration increases in NaCl. Yet, in KCl solution, it slightly increases and remains above bulk value as salt concentration increases. Previous classical molecular dynamics simulations have failed to describe this important behavior even when polarizable models were used. Here, we show that inclusion of dynamical charge transfer among water molecules produces results in a quantitative agreement with experiments. Our results indicate that the concentration-dependent diffusivity reflects the importance of many-body effects among the water molecules in aqueous ionic solutions. Comparison with quantum mechanical calculations shows that a heterogeneous and extended distribution of charges on water molecules around the ions due to ion-water and also water-water charge transfer plays a very important role in controlling water diffusivity. Explicit inclusion of the charge transfer allows us to model accurately the difference in the concentration-dependent water diffusivity between Na{sup +} and K{sup +} ions in simulations, and it is likely to impact modeling of a wide range of systems for medical and technological applications.

  2. Use of azeotropic distillation for isotopic analysis of deuterium in soil water and saturate saline solution

    International Nuclear Information System (INIS)

    Santos, Antonio Vieira dos.

    1995-05-01

    The azeotropic distillation technique was adapted to extract soil water and saturate saline solution, which is similar to the sea water for the Isotopic Determination of Deuterium (D). A soil test was used to determine the precision and the nature of the methodology to extract soil water for stable isotopic analysis, using the azeotropic distillation and comparing with traditional methodology of heating under vacuum. This methodology has been very useful for several kinds of soil or saturate saline solution. The apparatus does not have a memory effect, and the chemical reagents do not affect the isotopic composition of soil water. (author). 43 refs., 10 figs., 12 tabs

  3. Canned motor pumps at Heavy Water Project, Baroda [Paper No.: II-2

    International Nuclear Information System (INIS)

    Batra, R.K.; Waishampayan, S.G.

    1981-01-01

    Heavy Water Project, Baroda is having special canned motor pumps for pumping ammonia and potassium amide. These pumps work under a pressure of 640 kg/cm 2 and are lubricated and cooled by the same fluid. These pumps are having special bearings consisting of mating surfaces of tungsten carbine Vs ceramic or stellite Vs carbon depending upon application. The total number of such pumps installed in the plant is around 52. These pumps being installed in high pressure vessels working at a pressure of 640 kg/cm 2 have special maintenance problems and need special care during maintenance. Pumps once boxed up are completely out of reach for immediate maintenance if needed. The failure of these pumps may mean a down time of one to two months for the plant. Besides above, there are multistage barrel type ammonia pumps with 24 stages developing a pressure of 140 kg/cm 2 . All these equipments need special maintenance methods as the problems faced are varied and difficult to solve. This paper deals with general and unique type of problems faced on these pumps. (author)

  4. Electrolytic separation factors for oxygen isotopes in light and heavy water solutions

    International Nuclear Information System (INIS)

    Gulens, J.; Olmstead, W.J.; Longhurst, T.H.; Gale, K.L.; Rolston, J.H.

    1987-01-01

    The electrolytic separation factor, α, has been measured for /sup 17/O and /sup 18/O at Pt and Ni anodes in both light and heavy water solutions of 6M KOH as a function of current density. For oxygen-17, isotopic separation effects were not observed, within the experimental uncertainty of +-2%, under all conditions studied. For oxygen-18, there is a small difference of 2% in α values between Pt and Ni in both light and heavy water solutions, but there is no significant difference in α values between light and heavy water solutions. In light waters solutions, the separation factor at Pt is small, α(/sup 18/O) ≤ 1.02 for i ≥ 0.1 A/cm/sub 2/. This value agrees reasonably well with theoretical estimates

  5. Liquid-phase and vapor-phase dehydration of organic/water solutions

    Science.gov (United States)

    Huang, Yu [Palo Alto, CA; Ly, Jennifer [San Jose, CA; Aldajani, Tiem [San Jose, CA; Baker, Richard W [Palo Alto, CA

    2011-08-23

    Processes for dehydrating an organic/water solution by pervaporation or vapor separation using fluorinated membranes. The processes are particularly useful for treating mixtures containing light organic components, such as ethanol, isopropanol or acetic acid.

  6. Cotransport of water and solutes in plant membranes: The molecular basis, and physiological functions

    Directory of Open Access Journals (Sweden)

    Lars H. Wegner

    2017-03-01

    Full Text Available Current concepts of plant membrane transport are based on the assumption that water and solutes move across membranes via separate pathways. According to this view, coupling between the fluxes is more or less exclusively constituted via the osmotic force that solutes exert on water transport. This view is questioned here, and experimental evidence for a cotransport of water and solutes is reviewed. The overview starts with ion channels that provide pathways for both ion and water transport, as exemplified for maxi K+ channels from cytoplasmic droplets of Chara corallina. Aquaporins are usually considered to be selective for water (just allowing for slippage of some other small, neutral molecules. Recently, however, a “dual function” aquaporin has been characterized from Arabidopsis thaliana (AtPIP2.1 that translocates water and at the same time conducts cations, preferentially Na+. By analogy with mammalian physiology, other candidates for solute-water flux coupling are cation-chloride cotransporters of the CCC type, and transporters of sugars and amino acids. The last part is dedicated to possible physiological functions that could rely on solute-water cotransport. Among these are the generation of root pressure, refilling of embolized xylem vessels, fast turgor-driven movements of leaves, cell elongation (growth, osmoregulation and adjustment of buoyancy in marine algae. This review will hopefully initiate further research in the field.

  7. Vibration Analysis and Experimental Research of the Linear-Motor-Driven Water Piston Pump Used in the Naval Ship

    Directory of Open Access Journals (Sweden)

    Ye-qing Huang

    2016-01-01

    Full Text Available Aiming at the existing problems of traditional water piston pump used in the naval ship, such as low efficiency, high noise, large vibration, and nonintelligent control, a new type of linear-motor-driven water piston pump is developed and its vibration characteristics are analyzed in this research. Based on the 3D model of the structure, the simulation analyses including static stress analysis, modal analysis, and harmonic response analysis are conducted. The simulation results reveal that the mode shape under low frequency stage is mainly associated with the eccentricity swing of the piston rod. The vibration experiment results show that the resonance frequency of linear-motor-driven water piston pump is concentrated upon 500 Hz and 800 Hz in the low frequency range. The dampers can change the resonance frequency of the system to a certain extent. The vibration under triangular motion curve is much better than that of S curve, which is consistent with the simulation conclusion. This research provides an effective method to detect the vibration characteristics and a reference for design and optimization of the linear-motor-driven water piston pump.

  8. Madawaska River water management review : issues, concerns, solutions

    International Nuclear Information System (INIS)

    1999-01-01

    Public consultations were held by the Public Advisory Committee, the Ontario Ministry of Natural Resources (MNR) and Ontario Hydro (OH) Working Group and Steering Committee, in an effort to develop a water management system for the Madawaska River, that would address public interests such as public safety, maintenance of the aquatic ecosystem and hydroelectric power generation. Provision of long-term opportunities for broad public involvement in the river's management was an additional objective. The report emphasizes the importance of limiting conflicts between hydroelectric generation and recreation/tourism on the Madawaska River, which runs within the Madawaska Highlands, Algonquin Provincial Park and the Upper Ottawa Valley. The major competing uses for water management in the Madawaska River are: (1) hydroelectric generation, (2) flood control, (3) recreation and tourism, and (4) fish and aquatic ecosystems. Each of these are described in detail, with details of the responses to the issue description and recommended actions

  9. An integrated engineering solution in treating tailings pond water (TPW)

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Z. [Alberta Univ., Edmonton, AB (Canada)

    2010-07-01

    This presentation described the progress that has been made in the treatment of tailings pond water (TPW). Several treatment technologies were examined for their potential use. Any valid treatment methods must be technically practicable and economically feasible in treating TPW. An integrated TPW treatment process was proposed in this paper after reviewing recent published literature related to TPW treatment. The process was proposed based on knowledge and experience gained from municipal and other industrial water and wastewater treatment operations. This engineered treatment process consists of bioadsorption, bioflocculation, suspended sludge blanket filtration, clarification, ozonation, and coke assisted hybrid biodegradation. The proposed treatment process was aiming at environmental release and/or further reuse of the treated TPW. This proposed treatment process features the reuse of 2 waste materials in order to enhance the treatment efficiency, to increase financial feasibility, and to maximize environmental benefits of the treatment. tabs., figs.

  10. Selected specific rates of reactions of transients from water in aqueous solution. Hydrated electron, supplemental data. [Reactions with transients from water, with inorganic solutes, and with solutes

    Energy Technology Data Exchange (ETDEWEB)

    Ross, A.B.

    1975-06-01

    A compilation of rates of reactions of hydrated electrons with other transients and with organic and inorganic solutes in aqueous solution appeared in NSRDS-NBS 43, and covered the literature up to early 1971. This supplement includes additional rates which have been published through July 1973.

  11. Influence of organobentonite structure on toluene adsorption from water solution

    Directory of Open Access Journals (Sweden)

    Nuria Vidal

    2012-12-01

    Full Text Available Due to increase water pollution by organic compound derived from hydrocarbons such as toluene, several alternative technologies for remediation of polluted water have been originated. In this work natural bentonites were modified with cetyltrimethylammonium (CTMA+ for obtaining organophilic bentonites. The obtained CTMA-bentonites would be suitable for use as adsorbents of toluene present in water. The influence of structural characteristics of CTMA-bentonites on their adsorption capacity was studied. It was shown that adsorption of toluene depended on homogeneous interlayer space associated with arrangements of CTMA+ paraffin-monolayer and bilayer models, accompanied by a high degree ordering of the carbon chain of organic cation in both arrangements. However, packing density would not have an evident influence on the retention capacity of these materials. The solids obtained were characterized by chemical analysis, X-ray diffractions and infrared spectroscopy. Toluene adsorption was measured by UV-visible spectrophotometer. Adsorption capacity was studied by determining adsorption isotherms and adsorption coefficient calculation. The adsorption isotherms were straight-line indicating a partition phenomenon of toluene between the aqueous and organic phase present in organophilic bentonites.

  12. Composite Transport Model and Water and Solute Transport across Plant Roots: An Update

    Directory of Open Access Journals (Sweden)

    Yangmin X. Kim

    2018-02-01

    Full Text Available The present review examines recent experimental findings in root transport phenomena in terms of the composite transport model (CTM. It has been a well-accepted conceptual model to explain the complex water and solute flows across the root that has been related to the composite anatomical structure. There are three parallel pathways involved in the transport of water and solutes in roots – apoplast, symplast, and transcellular paths. The role of aquaporins (AQPs, which facilitate water flows through the transcellular path, and root apoplast is examined in terms of the CTM. The contribution of the plasma membrane bound AQPs for the overall water transport in the whole plant level was varying depending on the plant species, age of roots with varying developmental stages of apoplastic barriers, and driving forces (hydrostatic vs. osmotic. Many studies have demonstrated that the apoplastic barriers, such as Casparian bands in the primary anticlinal walls and suberin lamellae in the secondary cell walls, in the endo- and exodermis are not perfect barriers and unable to completely block the transport of water and some solute transport into the stele. Recent research on water and solute transport of roots with and without exodermis triggered the importance of the extension of conventional CTM adding resistances that arrange in series (epidermis, exodermis, mid-cortex, endodermis, and pericycle. The extension of the model may answer current questions about the applicability of CTM for composite water and solute transport of roots that contain complex anatomical structures with heterogeneous cell layers.

  13. Composite Transport Model and Water and Solute Transport across Plant Roots: An Update.

    Science.gov (United States)

    Kim, Yangmin X; Ranathunge, Kosala; Lee, Seulbi; Lee, Yejin; Lee, Deogbae; Sung, Jwakyung

    2018-01-01

    The present review examines recent experimental findings in root transport phenomena in terms of the composite transport model (CTM). It has been a well-accepted conceptual model to explain the complex water and solute flows across the root that has been related to the composite anatomical structure. There are three parallel pathways involved in the transport of water and solutes in roots - apoplast, symplast, and transcellular paths. The role of aquaporins (AQPs), which facilitate water flows through the transcellular path, and root apoplast is examined in terms of the CTM. The contribution of the plasma membrane bound AQPs for the overall water transport in the whole plant level was varying depending on the plant species, age of roots with varying developmental stages of apoplastic barriers, and driving forces (hydrostatic vs. osmotic). Many studies have demonstrated that the apoplastic barriers, such as Casparian bands in the primary anticlinal walls and suberin lamellae in the secondary cell walls, in the endo- and exodermis are not perfect barriers and unable to completely block the transport of water and some solute transport into the stele. Recent research on water and solute transport of roots with and without exodermis triggered the importance of the extension of conventional CTM adding resistances that arrange in series (epidermis, exodermis, mid-cortex, endodermis, and pericycle). The extension of the model may answer current questions about the applicability of CTM for composite water and solute transport of roots that contain complex anatomical structures with heterogeneous cell layers.

  14. Coconut water solutions for the preservation of spleen, ovary, and skin autotransplants in rats.

    Science.gov (United States)

    Schettino César, J M; Petroianu, A; de Souza Vasconcelos, L; Cardoso, V N; das Graças Mota, L; Barbosa, A J A; Vianna Soares, C D; Lima de Oliveira, A

    2015-03-01

    The purpose of this study was to evaluate the efficacy of coconut water in the preservation of spleen, ovary, and skin autotransplantations in rats. Fifty female Wistar rats were divided randomly into 5 groups on the basis of the following tissue graft preservation solutions: group 1, lactated Ringer's; group 2, Belzer's solution; group 3, mature coconut water; group 4, green coconut water; and group 5, modified green coconut water. In group 5, the green coconut water solution was modified to obtain the same electrolyte composition as Belzer's solution. The spleen, ovaries, and a skin fragment were removed from each animal, stored for 6 hours in one of the solutions, and then re-implanted. The recoveries of tissue functions were assessed 90 days after surgery by means of spleen scintigraphy and blood tests. The implanted tissues were collected for histological analyses. Higher immunoglobulin G levels were observed in the animals of group 5 than in the animals of group 1. Differences in follicle-stimulating hormone levels were observed between groups 1 and 2 (P coconut water group (P coconut water allowed for the preservation of the spleen, ovaries, and skin for 6 hours, and the normal functions of these tissues were maintained in rats. Copyright © 2015 Elsevier Inc. All rights reserved.

  15. Structure of human insulin monomer in water/acetonitrile solution

    Energy Technology Data Exchange (ETDEWEB)

    Bocian, Wojciech; Sitkowski, Jerzy; Bednarek, Elzbieta [National Medicines Institute (Poland); Tarnowska, Anna; Kawecki, Robert [Institute of Organic Chemistry Polish Academy of Sciences (Poland); Kozerski, Lech [National Medicines Institute (Poland)], E-mail: lkoz@icho.edu.pl

    2008-01-15

    Here we present evidence that in water/acetonitrile solvent detailed structural and dynamic information can be obtained for important proteins that are naturally present as oligomers under native conditions. An NMR-derived human insulin monomer structure in H{sub 2}O/CD{sub 3}CN, 65/35 vol%, pH 3.6 is presented and compared with the available X-ray structure of a monomer that forms part of a hexamer (Acta Crystallogr. 2003 Sec. D59, 474) and with NMR structures in water and organic cosolvent. Detailed analysis using PFGSE NMR, temperature-dependent NMR, dilution experiments and CSI proves that the structure is monomeric in the concentration and temperature ranges 0.1-3 mM and 10-30 deg. C, respectively. The presence of long-range interstrand NOEs, as found in the crystal structure of the monomer, provides the evidence for conservation of the tertiary structure. Starting from structures calculated by the program CYANA, two different molecular dynamics simulated annealing refinement protocols were applied, either using the program AMBER in vacuum (AMBER{sub V}C), or including a generalized Born solvent model (AMBER{sub G}B)

  16. Structure of human insulin monomer in water/acetonitrile solution

    International Nuclear Information System (INIS)

    Bocian, Wojciech; Sitkowski, Jerzy; Bednarek, Elzbieta; Tarnowska, Anna; Kawecki, Robert; Kozerski, Lech

    2008-01-01

    Here we present evidence that in water/acetonitrile solvent detailed structural and dynamic information can be obtained for important proteins that are naturally present as oligomers under native conditions. An NMR-derived human insulin monomer structure in H 2 O/CD 3 CN, 65/35 vol%, pH 3.6 is presented and compared with the available X-ray structure of a monomer that forms part of a hexamer (Acta Crystallogr. 2003 Sec. D59, 474) and with NMR structures in water and organic cosolvent. Detailed analysis using PFGSE NMR, temperature-dependent NMR, dilution experiments and CSI proves that the structure is monomeric in the concentration and temperature ranges 0.1-3 mM and 10-30 deg. C, respectively. The presence of long-range interstrand NOEs, as found in the crystal structure of the monomer, provides the evidence for conservation of the tertiary structure. Starting from structures calculated by the program CYANA, two different molecular dynamics simulated annealing refinement protocols were applied, either using the program AMBER in vacuum (AMBER V C), or including a generalized Born solvent model (AMBER G B)

  17. Investigation of water and saline solution drops evaporation on a solid substrate

    Directory of Open Access Journals (Sweden)

    Orlova Evgenija G.

    2014-01-01

    Full Text Available Experimental investigation water and saline solution drops evaporation on a solid substrate made of anodized aluminum is presented in the paper. Parameters characterizing drop profile have been obtained (contact angle, contact diameter, height. The specific evaporation rate has been calculated from obtained values. It was found that water and saline solution drops with concentration up to 9.1% evaporate in the pinning mode. However, with increasing the salt concentration in the solution up to 16.7% spreading mode was observed. Two stages of drop evaporation depending on change of the evaporation rate have been separated.

  18. Structure of fullerene aggregates in pyridine/water solutions by small-angle neutron scattering

    International Nuclear Information System (INIS)

    Aksenov, V.L.; Belushkin, A.V.; Avdeev, M.V.; Rosta, L.; Mihailovic, D.; Mrzel, A.; Serdyuk, I.N.; Timchenko, A.A.

    2001-01-01

    Results of small-angle neutron scattering experiments on fullerenes (C 60 ) in pyridine/water solutions are reported. They confirm conclusions of the previous studies, in particular, dynamic light scattering experiments. Aggregates with characteristic radius of about 20 nm are formed in the solutions. The contrast variation using different combinations of protonated/deuterated components (water and pyridine) of the solutions points to the small pyridine content inside the aggregates. This fact testifies that the aggregates consist of a massive fullerene core covered by a thin pyridine shell

  19. Thickening agent for flood water in secondary recovery of oil and for other aqueous salt solutions

    Energy Technology Data Exchange (ETDEWEB)

    Roth, H H

    1966-04-14

    Alkenyl-aromatic polymer sulfonates are good thickeners for some aqueous solutions, but addition of salts to such solutions reduces the desirable viscosity. High-molecular, water-soluble alkenyl-aromatic polymers which carry sulfonic acid or sulfonate groups substituted at the aromatic nuclei yield thickened solutions (e.g., for waterflooding) which are not influenced by the presence of water-soluble salts. Such polymers are derivatives of polyvinyltoluene, alone or in combination with about 5% acrylonitrile. It was also found that such thickening agents are less adsorbed on the rock matrix in a waterflood formation. (1 claim)

  20. Enthalpy of solution of potassium iodide in the water-formamide-dimethyl sulfoxide mixtures

    International Nuclear Information System (INIS)

    Belova, L.N.; Solov'ev, S.N.; Vorob'ev, A.F.

    1985-01-01

    Solution enthalpies are measured for potassium iodide in the water-formamide-dimethyl sulfoxide mixtures in a sealed oscillating calorimeter with an isothermal shell at a constant water molar fraction equal to 0.3; 0.5 and 0.7 at 298.15 K. A diagram of the dependence of solution enthalpies on the of mixed solvent composition is plotted. Deviations of experimental solution enthalpies from the calculated ones are negative over the entire concentration range studied, which testifies to the preferable solvatation of electrolyte by the formid and dimthyl sulfoxide molecules

  1. Kinetics of phenol degradation in water solutions under gamma-irradiation

    International Nuclear Information System (INIS)

    Guliyeva, U.A.; Gurbanov, M.A.; Abdullayev, E.T.

    2014-01-01

    Full text : In this work the chemical oxygen demand and change of phenol concentration at the radiolysis of aqueous solutions of phenol was studied. Irradiation conducted under gamma-irradiation of 60Co at static conditions and at room temperature. The main component is water, therefore the radiolysis process of water plays an important role in radiolytic degradation of phenol

  2. A thermodynamic approach to assess organic solute adsorption onto activated carbon in water

    KAUST Repository

    De Ridder, David J.; Verliefde, Arne R. D.; Heijman, Bas G J; Gelin, Simon; Pereira, Manuel Fernando Ribeiro; Rocha, Raquel P.; Figueiredo, José Luí s M; Amy, Gary L.; Van Dijk, Hans C.

    2012-01-01

    In this paper, the hydrophobicity of 13 activated carbons is determined by various methods; water vapour adsorption, immersion calorimetry, and contact angle measurements. The quantity and type of oxygen-containing groups on the activated carbon were measured and related to the methods used to measure hydrophobicity. It was found that the water-activated carbon adsorption strength (based on immersion calorimetry, contact angles) depended on both type and quantity of oxygen-containing groups, while water vapour adsorption depended only on their quantity. Activated carbon hydrophobicity measurements alone could not be related to 1-hexanol and 1,3-dichloropropene adsorption. However, a relationship was found between work of adhesion and adsorption of these solutes. The work of adhesion depends not only on activated carbon-water interaction (carbon hydrophobicity), but also on solute-water (solute hydrophobicity) and activated carbon-solute interactions. Our research shows that the work of adhesion can explain solute adsorption and includes the effect of hydrogen bond formation between solute and activated carbon. © 2012 Elsevier Ltd. All rights reserved.

  3. Formation of by-products at radiation - chemical treatment of water solutions of chloroform

    International Nuclear Information System (INIS)

    Ahmedov, S.A.; Abdullayev, E.T.; Gurbanov, M.A.; Gurbanov, A.H.; Ibadov, N.A.

    2006-01-01

    Full text: Radiation-chemical treatment is considered as a perspective method of water purification from chloroform. It provides the high level of purification (98 percent) of water solutions from chloroform and other chlorine-containing compounds. Meanwhile, other chlorine-containing products can be formed during the process of chloroform degradation and as a result of it the quality of water can change. This work studies the formation of by-products of γ-radiolysis of water solutions at various initial contents of chloroform. Dichlormethane and tetrachlorethane are identified as by-products. It is shown that at high contents of chloroform after certain adsorbed dose the forming products are reducing till their full disappearing. At small contents of chloroform in the studied interval of doses di-chlor-methane is forming. Differences of dose dependences of by-products at various contents of chloroform can be connected with the transition from radical mechanism to chain reaction at high concentrations of chloroform in solutions saturated by oxygen. pH-solutions also reduces during the radiation till pH=1, although this reduction also depends on initial concentration of chloroform. Essential change of pH occurs only at the radiolysis of water solutions containing chloroform ≥0,2 percent. And at radiating of 0,03 percent solution pH reduces only till 4 - 4,5

  4. A thermodynamic approach to assess organic solute adsorption onto activated carbon in water

    KAUST Repository

    De Ridder, David J.

    2012-08-01

    In this paper, the hydrophobicity of 13 activated carbons is determined by various methods; water vapour adsorption, immersion calorimetry, and contact angle measurements. The quantity and type of oxygen-containing groups on the activated carbon were measured and related to the methods used to measure hydrophobicity. It was found that the water-activated carbon adsorption strength (based on immersion calorimetry, contact angles) depended on both type and quantity of oxygen-containing groups, while water vapour adsorption depended only on their quantity. Activated carbon hydrophobicity measurements alone could not be related to 1-hexanol and 1,3-dichloropropene adsorption. However, a relationship was found between work of adhesion and adsorption of these solutes. The work of adhesion depends not only on activated carbon-water interaction (carbon hydrophobicity), but also on solute-water (solute hydrophobicity) and activated carbon-solute interactions. Our research shows that the work of adhesion can explain solute adsorption and includes the effect of hydrogen bond formation between solute and activated carbon. © 2012 Elsevier Ltd. All rights reserved.

  5. Application of Information Technology Solution for Early Warning Systems at Water Utilities

    Science.gov (United States)

    Bałut, Alicja

    2018-02-01

    Deployment of IT solutions in water utilities in Poland concerns nowadays lots beyond GIS implementation projects [1]. The scope of modern IT platforms is truly advanced software for complete management of water treatment processes and involved objects, including ranges of various types of equipment. There are multiply factors that disrupt required volumes of supplied water. They are normally classified as natural, accidental and intentional. This paper addresses potential residing in already deployed IT solutions of water utilities in and also in new ones being now developed. Primarily- from the perspective of intentional, terrorist threats. This document depicts operating procedures that are called in case of spotted contamination in a water supply (damage of key elements of the network infrastructure) or in case of an introduction factors. This paper also discusses relevant IT tools with access provided to network operators or water plant owners that are extremely useful in accurate pinpointing the treat and in following relevant operating procedures and related actions.

  6. Multiple periodic-soliton solutions of the (3+1)-dimensional generalised shallow water equation

    Science.gov (United States)

    Li, Ye-Zhou; Liu, Jian-Guo

    2018-06-01

    Based on the extended variable-coefficient homogeneous balance method and two new ansätz functions, we construct auto-Bäcklund transformation and multiple periodic-soliton solutions of (3 {+} 1)-dimensional generalised shallow water equations. Completely new periodic-soliton solutions including periodic cross-kink wave, periodic two-solitary wave and breather type of two-solitary wave are obtained. In addition, cross-kink three-soliton and cross-kink four-soliton solutions are derived. Furthermore, propagation characteristics and interactions of the obtained solutions are discussed and illustrated in figures.

  7. Experimental investigation on an ammonia-water-lithium bromide absorption refrigeration system without solution pump

    International Nuclear Information System (INIS)

    Wu Tiehui; Wu Yuyuan; Yu Zhiqiang; Zhao Haichen; Wu Honglin

    2011-01-01

    Highlights: → An absorption refrigeration system with ternary solution of NH 3 -H 2 O-LiBr was set up. → Performance of the NH 3 -H 2 O-LiBr system without solution pump was firstly tested. → Generator pressure in NH 3 -H 2 O-LiBr system was lower than the one in NH 3 -H 2 O system. → The COP of the NH 3 -H 2 O-LiBr system was 51.89% larger than the NH 3 -H 2 O binary system. → The optimum mass fraction of LiBr of about 23% led to the largest COP of 0.401. -- Abstract: Experimental researches were carried out on a novel ammonia-water-lithium bromide ternary solution absorption refrigeration and air-conditioning system without solution pump and distillation equipments. The experiments were conducted by using three kinds of NH 3 -H 2 O binary solution and 17 kinds of ternary solution with difference in mass fraction of NH 3 and LiBr. The experimental results showed that the vapor pressure of the generator in the system would be lower than that of the generator in an ammonia-water absorption system. In above two situations the same ammonia mass fraction and the same solution temperature were kept. The amplitude of vapor pressure decrease of the system generator would be larger with the increase of the mass fraction of LiBr. The maximum amplitude of decrease would be of 50%. With the increase of the mass fraction of LiBr, the coefficient of performance (COP) of the system would be increased initially, and then decreased later when the mass fraction of LiBr exceeded a certain value. This value was about 23% for the solution with ammonia mass fraction of 50% and 55%, and about 30% for the solution with ammonia mass fraction of 60%. Compared with the ammonia-water system, the COP of the ternary solution system with the same mass fraction of ammonia would increase up to 30%. With the ammonia mass fraction of 60% and LiBr mass fraction of 30% applied, the COP of the ternary solution system was increased up to 0.401. It was 51.89% higher than that when binary

  8. Temperature dependence of water-water and ion-water correlations in bulk water and electrolyte solutions probed by femtosecond elastic second harmonic scattering

    Science.gov (United States)

    Chen, Yixing; Dupertuis, Nathan; Okur, Halil I.; Roke, Sylvie

    2018-06-01

    The temperature dependence of the femtosecond elastic second harmonic scattering (fs-ESHS) response of bulk light and heavy water and their electrolyte solutions is presented. We observe clear temperature dependent changes in the hydrogen (H)-bond network of water that show a decrease in the orientational order of water with increasing temperature. Although D2O has a more structured H-bond network (giving rise to more fs-ESHS intensity), the relative temperature dependence is larger in H2O. The changes are interpreted in terms of the symmetry of H-bonds and are indicators of nuclear quantum effects. Increasing the temperature in electrolyte solutions decreases the influence of the total electrostatic field from ions on the water-water correlations, as expected from Debye-Hückel theory, since the Debye length becomes longer. The effects are, however, 1.9 times (6.3 times) larger than those predicted for H2O (D2O). Since fs-ESHS responses can be computed from known molecular coordinates, our observations provide a unique opportunity to refine quantum mechanical models of water.

  9. Effect of water content on dispersion of transferred solute in unsaturated porous media

    Energy Technology Data Exchange (ETDEWEB)

    Latrille, C. [CEA Saclay, DEN/DANS/DPC/SECR/L3MR, 91191 Gif sur Yvette (France)

    2013-07-01

    Estimating contaminant migration in the context of waste disposal and/or environmental remediation of polluted soils requires a complete understanding of the underlying transport processes. In unsaturated porous media, water content impacts directly on porous solute transfer. Depending on the spatial distribution of water content, the flow pathway is more complex than in water saturated media. Dispersivity is consequently dependent on water content. Non-reactive tracer experiments performed using unsaturated sand columns confirm the dependence of dispersivity with pore velocity; moreover, a power law relationship between dispersivity and water content is evidenced. (authors)

  10. Degradation of nicotine in water solutions using a water falling film DBD plasma reactor: direct and indirect treatment

    Science.gov (United States)

    Krupež, Jelena; Kovačević, Vesna V.; Jović, Milica; Roglić, Goran M.; Natić, Maja M.; Kuraica, Milorad M.; Obradović, Bratislav M.; Dojčinović, Biljana P.

    2018-05-01

    Nicotine degradation efficiency in water solutions was studied using a water falling film dielectric barrier discharge (DBD) reactor. Two different treatments were applied: direct treatment, the recirculation of the solution through a DBD reactor, and indirect treatment, the bubbling of the gas from the DBD through the porous filter into the solution. In a separate experiment, samples spiked with nicotine in double distilled water (ddH2O) and tap water were studied and compared after both treatments. Furthermore, the effects of the homogeneous catalysts, namely, Fe2+ and H2O2, were tested in the direct treatment. Nicotine degradation efficiency was determined using high-performance liquid chromatography. A degradation efficiency of 90% was achieved after the direct treatment catalyzed with Fe2+. In order to analyze the biodegradability, mineralization level, and toxicity of the obtained solutions, after all degradation procedures the values of the following parameters were determined: total organic carbon, chemical oxygen demand, biochemical oxygen demand, and the Artemia salina toxicity test. The results showed that an increase in biodegradability was obtained, after all treatments. A partial nicotine mineralization was achieved and the mortality of the A. salina organism decreased in the treated samples, all of which indicating the effective removal of nicotine and the creation of less toxic solutions. Nicotine degradation products were identified using ultrahigh-performance liquid chromatography coupled with a linear ion trap Orbitrap hybrid mass spectrometer and a simple mechanism for oxidative degradation of nicotine in non-thermal plasma systems is proposed.

  11. Recrystallization of freezable bound water in aqueous solutions of medium concentrations

    Institute of Scientific and Technical Information of China (English)

    赵立山; 潘礼庆; 纪爱玲; 曹则贤; 王强

    2016-01-01

    For aqueous solutions with freezable bound water, vitrification and recrystallization are mingled, which brings diffi-culty to application and misleads the interpretation of relevant experiments. Here, we report a quantification scheme for the freezable bound water based on the water-content dependence of glass transition temperature, by which also the concentra-tion range for the solutions that may undergo recrystallization finds a clear definition. Furthermore, we find that depending on the amount of the freezable bound water, different temperature protocols should be devised to achieve a complete recrys-tallization. Our results may be helpful for understanding the dynamics of supercooled aqueous solutions and for improving their manipulation in various industries.

  12. Installation design of pump motor control systems for supplied of the RSG-GAS secondary raw water cooling system

    International Nuclear Information System (INIS)

    Kiswanto; Teguh Sulistyo; M-Taufik

    2013-01-01

    It has designed already of an installation of the pump motor control system for supplied of raw water to fulfil the RSG-GAS secondary cooling system. The installation design of this plant is used to supply electrical energy from PLN and 3 phase generator to operate the pump motor embedded multilevel type, capacity, Q = 30 m 3 /h; electric power, PN = 4 kW; voltage, 380V/3-/50Hz, and Y connections that can be operated manually or automatically by using the automatic transfer switch. The results obtained recapitulation total load of 4 kW, the magnitude of the nominal current of 9.5 A; kind of safety and capacity are used NFB 16 A, use of this type of cable to the control panel is PLN NYY 6 mm 2 diameter maximum current capacity of 25 A cable and use the control panel to the pump motor cable type NYY 4 mm 2 diameter maximum current capacity of 20 A. The design of the pump motor control system installation is ready to be implemented. (author)

  13. The Energy and Water Emergency Module; A containerized solution for meeting the energy and water needs in protracted displacement situations

    International Nuclear Information System (INIS)

    Fuso Nerini, Francesco; Valentini, Francesco; Modi, Anish; Upadhyay, Govinda; Abeysekera, Muditha; Salehin, Sayedus; Appleyard, Eduardo

    2015-01-01

    Highlights: • Energy and water services are a key need in long-term displacement situations. • At present electricity is supplied mostly with diesel generators and water is imported. • On-site electricity and clean water production can decrease costs and increase security. • The proposed containerized solution produces electricity and purifies water locally. • Model results show the cost-competitiveness and technical potential of the solution. - Abstract: The world has faced many natural and man-made disasters in the past few years, resulting in millions of people living in temporary camps across the globe. The energy and clean water needs of the relief operators in such emergency situations are primarily satisfied by diesel engine based generators and importing clean water to the site, in certain cases even for several years after the emergency. This approach results in problems such as low security of supply and high costs. Especially targeting the prolonged displacement situations, this paper presents an alternative solution – the Energy and Water Emergency Module. The proposed solution aims towards reducing the dependency on fossil fuel in prolonged emergency situations to a minimum while including local energy sources in the energy supply in a flexible and reliable way. The proposed module is built in a standard 20 ft container, and encompasses hybrid generation from solar, wind and biomass, with the possibility of using fossil sources too thanks to a dual fuel gas engine. The module can work both in grid connected and stand-alone mode. In addition the module includes a water purification unit to meet the water needs of displaced population. A demonstration unit was assembled at the Royal Institute of Technology in Stockholm during the year 2012 as a ‘concept proof’, and is now being tested and optimized for future deployment on the field. Preliminary testing and modelling shows that the proposed solution can reliably support emergency

  14. Land-Water-Food Nexus and Indications of Crop Adjustment for Water Shortage Solution

    Science.gov (United States)

    Yang, Y.; Ren, D.; Zhou, X.

    2017-12-01

    Agriculture places the greatest demand on water resources, and increasing agricultural production is worsening a global water shortage. Reducing the cultivation of water-consuming crops may be the most effective way to reduce agricultural water use. However, when also taking food demand into consideration, sustaining the balance between regional water and food securities is a growing challenge. This paper addresses this task for regions where water is unsustainable for food production (Beijing-Tianjin-Hebei Region for example), by (i) assessing the different effects of wheat and maize on water use; (ii) analyzing virtual water and virtual land flows associated with food imports and exports between Beijing-Tianjin-Hebei and elsewhere in China; (iii) identifying sub-regions where grain are produced using scarce water resources but exported to other regions. (iv) analyzing the potentiality for mitigating water shortage via Land-Water-Food Nexus. In the Beijing-Tianjin-Hebei Region, the study reveals that 29.76 bn m3 of virtual water (10.81 bn m3 of blue virtual water) are used by wheat and maize production and nearly 2 million ha of cropland using 8.77 bn m3 of virtual water overproduced 12 million ton of maize for external food consumption. As an importing-based sub-region with high population density, Beijing and Tianjin (BT) imported mostly grain (wheat and maize) from Shandong (SD). Whereas, Hebei (HB), as an exporting-based sub-region with sever water shortage, overproduced too much grain for other regions (like Central area), which aggravated water crisis. To achieve Beijing-Tianjin-Hebei's integrated and sustainable development, HB should not undertake the breadbasket role for BT but pay more attention to groundwater depletion. The analysis of the Land-Water-Food Nexus indicates how shifts in the cultivated crops can potentially solve the overuse of water resources without adverse effect on food supply, and provides meaningful information to support policy

  15. Modeling Global Water Use for the 21st Century: Water Futures and Solutions (WFaS) Initiative and Its Approaches

    Science.gov (United States)

    Wada, Y.; Florke, M.; Hanasaki, N.; Eisner, S.; Fischer, G.; Tramberend, S.; Satoh, Y.; van Vliet, M. T. H.; Yillia, P.; Ringler, C.; hide

    2016-01-01

    To sustain growing food demand and increasing standard of living, global water use increased by nearly 6 times during the last 100 years, and continues to grow. As water demands get closer and closer to the water availability in many regions, each drop of water becomes increasingly valuable and water must be managed more efficiently and intensively. However, soaring water use worsens water scarcity conditions already prevalent in semi-arid and arid regions, increasing uncertainty for sustainable food production and economic development. Planning for future development and investments requires that we prepare water projections for the future. However, estimations are complicated because the future of the world's waters will be influenced by a combination of environmental, social, economic, and political factors, and there is only limited knowledge and data available about freshwater resources and how they are being used. The Water Futures and Solutions (WFaS) initiative coordinates its work with other ongoing scenario efforts for the sake of establishing a consistent set of new global water scenarios based on the shared socio-economic pathways (SSPs) and the representative concentration pathways (RCPs). The WFaS "fast track" assessment uses three global water models, namely H08, PCR-GLOBWB, and WaterGAP. This study assesses the state of the art for estimating and projecting water use regionally and globally in a consistent manner. It provides an overview of different approaches, the uncertainty, strengths and weaknesses of the various estimation methods, types of management and policy decisions for which the current estimation methods are useful. We also discuss additional information most needed to be able to improve water use estimates and be able to assess a greater range of management options across the water-energy-climate nexus.

  16. Fractionation of hydrogen and oxygen isotopes between hydrated and free water molecules in aqueous urea solution

    International Nuclear Information System (INIS)

    Kakiuchi, M.; Matsuo, S.

    1985-01-01

    Ratios of D/H and 18 O/ 16 O in the vapor phase in equilibrium with aqueous urea solution with different urea molalities were measured at 15 and 25 0 C. Under the assumption that urea solutions consist of two species, i.e., the urea-water cluster and free water, the results are interpreted to give the average hydration number, i.e., the number of water molecules per urea molecule in the urea-water cluster. Good agreement was obtained for the hydration number estimated independently from hydrogen and oxygen isotopic fractions. On the basis of hydrogen isotopic data at 25 0 C, the average hydration number of urea in the cluster is 6.3 +/- 0.8 at 2.1 m and 2.75 +/- 0.08 at saturation (20.15 m). The corresponding average hydration numbers based on oxygen isotopic data were calculated to be 6.7 +/- 2.4 at 2.1 m and 2.75 +/- 0.25 at urea saturation. HD 16 O is enriched in the urea-water cluster and H 2 18 O is enriched in free water. Isotopic partitioning between the cluster and free water is markedly different from those between hydration spheres and free water in aqueous electrolyte solutions. 29 references, 6 figures, 5 tables

  17. Ground-water solute transport modeling using a three-dimensional scaled model

    International Nuclear Information System (INIS)

    Crider, S.S.

    1987-01-01

    Scaled models are used extensively in current hydraulic research on sediment transport and solute dispersion in free surface flows (rivers, estuaries), but are neglected in current ground-water model research. Thus, an investigation was conducted to test the efficacy of a three-dimensional scaled model of solute transport in ground water. No previous results from such a model have been reported. Experiments performed on uniform scaled models indicated that some historical problems (e.g., construction and scaling difficulties; disproportionate capillary rise in model) were partly overcome by using simple model materials (sand, cement and water), by restricting model application to selective classes of problems, and by physically controlling the effect of the model capillary zone. Results from these tests were compared with mathematical models. Model scaling laws were derived for ground-water solute transport and used to build a three-dimensional scaled model of a ground-water tritium plume in a prototype aquifer on the Savannah River Plant near Aiken, South Carolina. Model results compared favorably with field data and with a numerical model. Scaled models are recommended as a useful additional tool for prediction of ground-water solute transport

  18. Water and solute balances as a basis for sustainable irrigation agriculture

    Science.gov (United States)

    Pla-Sentís, Ildefonso

    2015-04-01

    The growing development of irrigated agriculture is necessary for the sustainable production of the food required by the increasing World's population. Such development is limited by the increasing scarcity and low quality of the available water resources and by the competitive use of the water for other purposes. There are also increasing problems of contamination of surface and ground waters to be used for other purposes by the drainage effluents of irrigated lands. Irrigation and drainage may cause drastic changes in the regime and balance of water and solutes (salts, sodium, contaminants) in the soil profile, resulting in problems of water supply to crops and problems of salinization, sodification and contamination of soils and ground waters. This is affected by climate, crops, soils, ground water depth, irrigation and groundwater composition, and by irrigation and drainage management. In order to predict and prevent such problems for a sustainable irrigated agriculture and increased efficiency in water use, under each particular set of conditions, there have to be considered both the hydrological, physical and chemical processes determining such water and solute balances in the soil profile. In this contribution there are proposed the new versions of two modeling approaches (SOMORE and SALSODIMAR) to predict those balances and to guide irrigation water use and management, integrating the different factors involved in such processes. Examples of their application under Mediterranean and tropical climate conditions are also presented.

  19. Study of the separation of strontium from solutions which imitate natural waters of increased mineralization

    International Nuclear Information System (INIS)

    Golub, A.M.; Voitko, I.N.; Glushchenko, L.V.; Mitrofanova, O.G.; Zyryanova, N.P.

    1976-01-01

    It has been shown by experiments on synthetically prepared solutions that it is possible to separate strontium and calcium by carbonate precipitation from the larger part of the magnesium accompanying them in natural high mineral waters. In this way the residual content of strontium is reduced to a value of 40-50 mg/liter and, under conditions of removing CO 2 from the solution, to 5-10 mg/liter. The high ionic strength of the solution prevented a more complete precipitation of strontium. Magnesium may be isolated from the filtrate after precipitation of the calcium-strontium mixture. The possibility has been shown of isolating strontium from the mixture of carbonates by means of pyrolysis at 1100-1200 0 and the selective solution of SrO in hot water

  20. Vibrational spectra of water solutions of azoles from QM/MM calculations: effects of solvation.

    Science.gov (United States)

    Tanzi, Luana; Ramondo, Fabio; Guidoni, Leonardo

    2012-10-18

    Using microsolvation models and mixed quantum/classical ab initio molecular dynamics simulations, we investigate the vibrational properties of two azoles in water solution: pyrazole and oxazole. The effects of the water-azole hydrogen bonding are rationalized by an extensive comparison between structural parameters and harmonic frequencies obtained by microsolvation models. Following the effective normal-mode analysis introduced by Martinez et al. [Martinez et al., J. Chem. Phys. 2006, 125, 144106], we identify the vibrational frequencies of the solutes using the decomposition of the vibrational density of states of the gas phase and solution dynamics. The calculated shifts from gas phase to solution are fairly in agreement with the available experimental data.

  1. The Energy and Water Emergency Module; A containerized solution for meeting the energy and water needs in protracted displacement situations

    DEFF Research Database (Denmark)

    Nerini, Francesco Fuso; Valentini, Francesco; Modi, Anish

    2015-01-01

    The world has faced many natural and man-made disasters in the past few years, resulting in millions of people living in temporary camps across the globe. The energy and clean water needs of the relief operators in such emergency situations are primarily satisfied by diesel engine based generators...... and importing clean water to the site, in certain cases even for several years after the emergency. This approach results in problems such as low security of supply and high costs. Especially targeting the prolonged displacement situations, this paper presents an alternative solution – the Energy and Water...

  2. 2012 Gordon Research Conference on Water and Aqueous Solutions, Final Progress Report

    Energy Technology Data Exchange (ETDEWEB)

    Ben-Amotz, Dor [Purdue Univ., West Lafayette, IN (United States)

    2012-08-17

    Understanding the fundamental principles governing the structure and dynamics of water - and particularly how water mediates chemical interactions and processes - continues to pose formidable challenges and yield abundant surprises. The focus of this Gordon Research Conference is on identifying key questions, describing emerging understandings, and unveiling surprising discoveries related to water and aqueous solutions. The talks and posters at this meeting will describe studies of water and its interactions with objects such as interfaces, channels, electrons, oils, ions, and proteins; probed using optical, electrical, and particle experiments, and described using classical, quantum, and multi-scale theories.

  3. DMSO-Water Clustering in Solution Observed in Soft X-ray Spectra.

    Science.gov (United States)

    Engel, Nicholas; Atak, Kaan; Lange, Kathrin M; Gotz, Malte; Soldatov, Mikhail; Golnak, Ronny; Suljoti, Edlira; Rubensson, Jan-Erik; Aziz, Emad F

    2012-12-20

    The significant deviation from the ideality of dimethyl sulfoxide (DMSO)/water mixtures can be addressed based on the change of the local molecular orbitals of each solvent upon mixing. Oxygen K-edge absorption and emission spectra of DMSO/water solutions were measured using the liquid microjet technique. The spectra demonstrate that the hydrogen bond network in liquid water is already influenced at small DMSO concentrations, and at the molar fraction xDMSO = 0.43 we find strong evidence of DMSO-water clustering reflected by the influence on the occupied molecular orbitals.

  4. Method of determining local distribution of water or aqueous solutions penetrated into plastics

    International Nuclear Information System (INIS)

    Krejci, M.; Joks, Z.

    1983-01-01

    Penetrating water is labelled with tritium and the distribution is autoradiographically monitored. The discovery consists in that the plastic with the penetrating water or aqueous solution is cooled with liquid nitrogen and under the stream of liquid nitrogen the plastic is cut and exposed on the autoradiographic film in the freezer at temperatures from -15 to -30 degC. The autoradiogram will show the distribution of water in the whole area of the section. The described method may be used to detect water distribution also in filled plastics. (J.P.)

  5. Effect of Hfe Deficiency on Memory Capacity and Motor Coordination after Manganese Exposure by Drinking Water in Mice.

    Science.gov (United States)

    Alsulimani, Helal Hussain; Ye, Qi; Kim, Jonghan

    2015-12-01

    Excess manganese (Mn) is neurotoxic. Increased manganese stores in the brain are associated with a number of behavioral problems, including motor dysfunction, memory loss and psychiatric disorders. We previously showed that the transport and neurotoxicity of manganese after intranasal instillation of the metal are altered in Hfe-deficient mice, a mouse model of the iron overload disorder hereditary hemochromatosis (HH). However, it is not fully understood whether loss of Hfe function modifies Mn neurotoxicity after ingestion. To investigate the role of Hfe in oral Mn toxicity, we exposed Hfe-knockout (Hfe (-/-)) and their control wild-type (Hfe (+/+)) mice to MnCl2 in drinking water (5 mg/mL) for 5 weeks. Motor coordination and spatial memory capacity were determined by the rotarod test and the Barnes maze test, respectively. Brain and liver metal levels were analyzed by inductively coupled plasma mass spectrometry. Compared with the water-drinking group, mice drinking Mn significantly increased Mn concentrations in the liver and brain of both genotypes. Mn exposure decreased iron levels in the liver, but not in the brain. Neither Mn nor Hfe deficiency altered tissue concentrations of copper or zinc. The rotarod test showed that Mn exposure decreased motor skills in Hfe (+/+) mice, but not in Hfe (-/-) mice (p = 0.023). In the Barns maze test, latency to find the target hole was not altered in Mn-exposed Hfe (+/+) compared with water-drinking Hfe (+/+) mice. However, Mn-exposed Hfe (-/-) mice spent more time to find the target hole than Mn-drinking Hfe (+/+) mice (p = 0.028). These data indicate that loss of Hfe function impairs spatial memory upon Mn exposure in drinking water. Our results suggest that individuals with hemochromatosis could be more vulnerable to memory deficits induced by Mn ingestion from our environment. The pathophysiological role of HFE in manganese neurotoxicity should be carefully examined in patients with HFE-associated hemochromatosis and

  6. The Modification of Sodium Polyacrylate Water Solution Cooling Properties by AL2O3

    Directory of Open Access Journals (Sweden)

    Wojciech Gęstwa

    2010-01-01

    Based on cooling curves, it can be concluded that for the water solution of sodium polyacrylate with AL2O3 nanoparticles in comparison to water and 10% polymer water solution lower cooling speed is obtained. The cooling medium containing nanoparticles provides lower cooling speed in the smallest surface austenite occurance (500–600 C in the charts of the CTP for most nonalloy structural steels and low-alloy steels. However lower cooling temperature at the beginning of martensitic transformation causes the formation of smaller internal stresses, leading to smaller dimensional changes and hardening deformation. For the quenching media the wetting angle was appointed by the drop-shape method. These studies showed the best wettability of polymer water solution (sodium polyacrylate with the addition of AL2O3 nanoparticles, whose wetting angle was about 65 degrees. Obtaining the smallest wetting angle for the medium containing nanoparticles suggests that the heat transfer to the cooling medium is larger. This allows slower cooling at the same time ensuring its homogeneity. The obtained values of wetting angle confirm the conclusions drawn on the basis of cooling curves and allowus to conclude that in the case of the heat transfer rate it will have a lower value than for water and 10% polymer water solution. In the research on hardened carburized steel samples C10 and 16MnCr5 surface hardness, impact strength and changes in the size of cracks in Navy C-ring sample are examined. On this basis of the obtained results it can be concluded that polymer water solution with nanoparticles allows to obtain a better impact strength at comparable hardness on the surface. Research on the dimensional changes on the basis of the sample of Navy C-ring also shows small dimensional changes for samples carburized and hardened in 10% polymer water solution with the addition of nanoparticles AL2O3. Smaller dimensional changes were obtained for samples of steel 16MnCr5 thanfar C10. The

  7. Effect on growth and nickel content of cabbage plants watered with nickel solutions

    Energy Technology Data Exchange (ETDEWEB)

    Christensen, O B

    1979-01-01

    Chinese cabbage plants were watered with different concentrations of NiCl/sub 2/ solutions and the effect on growth and uptake of nickel in the plants were studied. No toxic effect on plant growth was observed. A higher content of nickel was found in the plants exposed to more concentrated nickel solutions. Nickel contamination and its clinical consequences are discussed. 29 references, 1 figure, 1 table.

  8. Approximate analytical solution to the Boussinesq equation with a sloping water-land boundary

    Science.gov (United States)

    Tang, Yuehao; Jiang, Qinghui; Zhou, Chuangbing

    2016-04-01

    An approximate solution is presented to the 1-D Boussinesq equation (BEQ) characterizing transient groundwater flow in an unconfined aquifer subject to a constant water variation at the sloping water-land boundary. The flow equation is decomposed to a linearized BEQ and a head correction equation. The linearized BEQ is solved using a Laplace transform. By means of the frozen-coefficient technique and Gauss function method, the approximate solution for the head correction equation can be obtained, which is further simplified to a closed-form expression under the condition of local energy equilibrium. The solutions of the linearized and head correction equations are discussed from physical concepts. Especially for the head correction equation, the well posedness of the approximate solution obtained by the frozen-coefficient method is verified to demonstrate its boundedness, which can be further embodied as the upper and lower error bounds to the exact solution of the head correction by statistical analysis. The advantage of this approximate solution is in its simplicity while preserving the inherent nonlinearity of the physical phenomenon. Comparisons between the analytical and numerical solutions of the BEQ validate that the approximation method can achieve desirable precisions, even in the cases with strong nonlinearity. The proposed approximate solution is applied to various hydrological problems, in which the algebraic expressions that quantify the water flow processes are derived from its basic solutions. The results are useful for the quantification of stream-aquifer exchange flow rates, aquifer response due to the sudden reservoir release, bank storage and depletion, and front position and propagation speed.

  9. A third-order asymptotic solution of nonlinear standing water waves in Lagrangian coordinates

    International Nuclear Information System (INIS)

    Yang-Yih, Chen; Hung-Chu, Hsu

    2009-01-01

    Asymptotic solutions up to third-order which describe irrotational finite amplitude standing waves are derived in Lagrangian coordinates. The analytical Lagrangian solution that is uniformly valid for large times satisfies the irrotational condition and the pressure p = 0 at the free surface, which is in contrast with the Eulerian solution existing under a residual pressure at the free surface due to Taylor's series expansion. In the third-order Lagrangian approximation, the explicit parametric equation and the Lagrangian wave frequency of water particles could be obtained. In particular, the Lagrangian mean level of a particle motion that is a function of vertical label is found as a part of the solution which is different from that in an Eulerian description. The dynamic properties of nonlinear standing waves in water of a finite depth, including particle trajectory, surface profile and wave pressure are investigated. It is also shown that the Lagrangian solution is superior to an Eulerian solution of the same order for describing the wave shape and the kinematics above the mean water level. (general)

  10. One-step microwave synthesis of photoluminescent carbon nanoparticles from sodium dextran sulfate water solution

    Science.gov (United States)

    Kokorina, Alina A.; Goryacheva, Irina Y.; Sapelkin, Andrei V.; Sukhorukov, Gleb B.

    2018-04-01

    Photoluminescent (PL) carbon nanoparticles (CNPs) have been synthesized by one-step microwave irradiation from water solution of sodium dextran sulfate (DSS) as the sole carbon source. Microwave (MW) method is very simple and cheap and it provides fast synthesis of CNPs. We have varied synthesis time for obtaining high luminescent CNPs. The synthesized CNPs exhibit excitation-dependent photoluminescent. Final CNPs water solution has a blue- green luminescence. CNPs have low cytotoxicity, good photostability and can be potentially suitable candidates for bioimaging, analysis or analytical tests.

  11. Analytical solution using computer algebra of a biosensor for detecting toxic substances in water

    Science.gov (United States)

    Rúa Taborda, María. Isabel

    2014-05-01

    In a relatively recent paper an electrochemical biosensor for water toxicity detection based on a bio-chip as a whole cell was proposed and numerically solved and analyzed. In such paper the kinetic processes in a miniaturized electrochemical biosensor system was described using the equations for specific enzymatic reaction and the diffusion equation. The numerical solution shown excellent agreement with the measured data but such numerical solution is not enough to design efficiently the corresponding bio-chip. For this reason an analytical solution is demanded. The object of the present work is to provide such analytical solution and then to give algebraic guides to design the bio-sensor. The analytical solution is obtained using computer algebra software, specifically Maple. The method of solution is the Laplace transform, with Bromwich integral and residue theorem. The final solution is given as a series of Bessel functions and the effective time for the bio-sensor is computed. It is claimed that the analytical solutions that were obtained will be very useful to predict further current variations in similar systems with different geometries, materials and biological components. Beside of this the analytical solution that we provide is very useful to investigate the relationship between different chamber parameters such as cell radius and height; and electrode radius.

  12. Calculated k-effectives for light water reactor typical, U + Pu nitrate solution critical experiments

    International Nuclear Information System (INIS)

    Primm, R.T. III; Mincey, J.F.

    1982-01-01

    The Department of Energy's Consolidated Fuel Reprocessing Program has as a goal the design of nuclear fuel reprocessing equipment. In order to validate computer codes used for criticality analyses in the design of such equipment, k-effectives have been calculated for several U + Pu nitrate solution critical experiments. As of January 1981, descriptions of 45 unpoisoned, U + Pu solution experiments were available in the open literature. Twelve of these experiments were performed with solutions which have physical characteristics typical of dissolved, light water reactor fuel. This paper contains a discussion of these twelve experiments, a review of the calculational procedure used to determine k-effectives, and the results of the calculations

  13. Non-Invasive Acoustic-Based Monitoring of Heavy Water and Uranium Process Solutions

    Energy Technology Data Exchange (ETDEWEB)

    Pantea, Cristian [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Sinha, Dipen N. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Lakis, Rollin Evan [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Beedle, Christopher Craig [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Davis, Eric Sean [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-10-20

    This presentation includes slides on Project Goals; Heavy Water Production Monitoring: A New Challenge for the IAEA; Noninvasive Measurements in SFAI Cell; Large Scatter in Literature Values; Large Scatter in Literature Values; Highest Precision Sound Speed Data Available: New Standard in H/D; ~400 pts of data; Noninvasive Measurements in SFAI Cell; New funding from NA241 SGTech; Uranium Solution Monitoring: Inspired by IAEA Challenge in Kazakhstan; Non-Invasive Acoustic-Based Monitoring of Uranium in Solutions; Non-Invasive Acoustic-Based Monitoring of Uranium in Solutions; and finally a summary.

  14. Land-Water-Food Nexus and indications of crop adjustment for water shortage solution.

    Science.gov (United States)

    Ren, Dandan; Yang, Yonghui; Yang, Yanmin; Richards, Keith; Zhou, Xinyao

    2018-06-01

    While agriculture places the greatest demand on water resources, increasing agricultural production is worsening a global water shortage. Reducing the cultivation of water-consuming crops may be the most effective way to reduce agricultural water use. However, when also taking food demand into consideration, sustaining the balance between regional water and food securities is a growing challenge. This paper addresses this task for regions where water is unsustainable for food production (Beijing-Tianjin-Hebei Region for example) by: (i) assessing the different effects of wheat and maize on water use; (ii) analyzing virtual water and virtual land flows associated with food imports and exports between Beijing-Tianjin-Hebei and elsewhere in China; (iii) identifying sub-regions where grain is produced using scarce water resources but exported to other regions; and (iv) analyzing the potentiality for mitigating water shortage via Land-Water-Food Nexus. In the Beijing-Tianjin-Hebei Region, the study reveals that 29.76 bn m 3 of virtual water (10.81 bn m 3 of blue virtual water) are used by wheat and maize production and 8.77 bn m 3 of virtual water used in nearly 2 million ha of cropland to overproduce 12 million ton of maize for external food consumption. As an importing-based sub-region with high population density, Beijing & Tianjin imported mostly grain (wheat and maize) from Shandong Province. Then, Hebei Province, as an exporting-based sub-region with severe water shortage, overproduced too much grain for other regions, which aggravated the water crisis. To achieve an integrated and sustainable development of the Beijing-Tianjin-Hebei Region, Hebei Province should stop undertaking the breadbasket role for Beijing & Tianjin and pay more attention to groundwater depletion. The analysis of the Land-Water-Food Nexus indicates how shifts in cultivated crops can potentially solve the overuse of water resources without adverse effects on food supply

  15. Highly Water-Soluble Magnetic Nanoparticles as Novel Draw Solutes in Forward Osmosis for Water Reuse

    KAUST Repository

    Ling, Ming Ming; Wang, Kai Yu; Chung, Tai-Shung

    2010-01-01

    of different diameters were also synthesized to study the effect of particles size on FO performance. We demonstrate that the engineering of surface hydrophilicity and magnetic nanoparticle size is crucial in the application of nanoparticles as draw solutes

  16. Extraction-spectrophotometric determination of purine alkaloids in water solutions using aliphatic alcohols

    Directory of Open Access Journals (Sweden)

    Y. I. Korenman

    2012-01-01

    Full Text Available For extraction of caffeine, theobromin and theophylline from water solutions are applied aliphatic alcohols С3 – С9. Water concentrates analyzed method UF- spectrophotometry. Factors of distribution and extraction degree are calculated. Influence of length of a hydrocarbonic radical in a solvent and nature olecule salting-out agent on interphase distribution of alkaloids is studied. Dependence of quantitative characteristics extraction from number active groups in structure alkaloids is established.

  17. Solvation thermodynamics and heat capacity of polar and charged solutes in water

    Science.gov (United States)

    Sedlmeier, Felix; Netz, Roland R.

    2013-03-01

    The solvation thermodynamics and in particular the solvation heat capacity of polar and charged solutes in water is studied using atomistic molecular dynamics simulations. As ionic solutes we consider a F- and a Na+ ion, as an example for a polar molecule with vanishing net charge we take a SPC/E water molecule. The partial charges of all three solutes are varied in a wide range by a scaling factor. Using a recently introduced method for the accurate determination of the solvation free energy of polar solutes, we determine the free energy, entropy, enthalpy, and heat capacity of the three different solutes as a function of temperature and partial solute charge. We find that the sum of the solvation heat capacities of the Na+ and F- ions is negative, in agreement with experimental observations, but our results uncover a pronounced difference in the heat capacity between positively and negatively charged groups. While the solvation heat capacity ΔCp stays positive and even increases slightly upon charging the Na+ ion, it decreases upon charging the F- ion and becomes negative beyond an ion charge of q = -0.3e. On the other hand, the heat capacity of the overall charge-neutral polar solute derived from a SPC/E water molecule is positive for all charge scaling factors considered by us. This means that the heat capacity of a wide class of polar solutes with vanishing net charge is positive. The common ascription of negative heat capacities to polar chemical groups might arise from the neglect of non-additive interaction effects between polar and apolar groups. The reason behind this non-additivity is suggested to be related to the second solvation shell that significantly affects the solvation thermodynamics and due to its large spatial extent induces quite long-ranged interactions between solvated molecular parts and groups.

  18. Simulations of water and solute movement in the buried waste repository at Vaalputs

    International Nuclear Information System (INIS)

    Hutson, J.L.

    1987-01-01

    A previous series of simulations examined the movement of water through trench cap configurations of several types. The objectives of this series are i) to extent the simulations from the surface to the bottom of the repository, accounting for the placement of drums, ii) to examine the magnitude and direction of water fluxes throughout this depth and iii) to simulate the movement of solutes, using various assumptions regarding solute adsorption. Two models were used. The first was an adaptation of a solute transport model which incorporates the transient water flow model used in previous simulations. This was used primarily to estimate the likely water fluxes in the drum placement region. Since it requires large amounts of computer time this model was used to simulate periods of one or two years only. The second model was a very simple steady state solute transport model which was used to simulate Cs distribution after a 100 year period, using flux data obtained from the transient model simulations. The most important conclusion reached from this series of simulations is that the movement of Cs in the soil under the likely water regime is extremely slow. 'Worst case' situations were simulated. Some of these situations are unlikely in reality but provide a useful indication of the rates of movement of solute under various conditions. For this reason it was assumed that plants were absent in cases when maximum percolation was simulated and present when maximum upward flow was simulated. In no case was a 'wick' (a textural barrier to unsaturated water flow) assumed to be present

  19. Some exact solutions to the potential Kadomtsev-Petviashvili equation and to a system of shallow water wave equations

    International Nuclear Information System (INIS)

    Inan, Ibrahim E.; Kaya, Dogan

    2006-01-01

    In this Letter by considering an improved tanh function method, we found some exact solutions of the potential Kadomtsev-Petviashvili equation. Some exact solutions of the system of the shallow water wave equation were also found

  20. Molecular dynamics study of salt–solution interface: Solubility and surface charge of salt in water

    International Nuclear Information System (INIS)

    Kobayashi, Kazuya; Liang, Yunfeng; Matsuoka, Toshifumi; Sakka, Tetsuo

    2014-01-01

    The NaCl salt–solution interface often serves as an example of an uncharged surface. However, recent laser-Doppler electrophoresis has shown some evidence that the NaCl crystal is positively charged in its saturated solution. Using molecular dynamics (MD) simulations, we have investigated the NaCl salt–solution interface system, and calculated the solubility of the salt using the direct method and free energy calculations, which are kinetic and thermodynamic approaches, respectively. The direct method calculation uses a salt–solution combined system. When the system is equilibrated, the concentration in the solution area is the solubility. In the free energy calculation, we separately calculate the chemical potential of NaCl in two systems, the solid and the solution, using thermodynamic integration with MD simulations. When the chemical potential of NaCl in the solution phase is equal to the chemical potential of the solid phase, the concentration of the solution system is the solubility. The advantage of using two different methods is that the computational methods can be mutually verified. We found that a relatively good estimate of the solubility of the system can be obtained through comparison of the two methods. Furthermore, we found using microsecond time-scale MD simulations that the positively charged NaCl surface was induced by a combination of a sodium-rich surface and the orientation of the interfacial water molecules

  1. Potential of Nanotechnology based water treatment solutions for the improvement of drinking water supplies in developing countries

    Science.gov (United States)

    Dutta, Joydeep; Bhattacharya, Prosun; Bundschuh, Jochen

    2016-04-01

    Over the last decades explosive population growth in the world has led to water scarcity across the globe putting additional pressure already scarce ground water resources and is pushing scientists and researchers to come up with new alternatives to monitor and treat water for use by mankind and for food security. Nearly 4 billion people around the world are known to lack access to clean water supply. Systematic water quality data is important for the assessment of health risks as well as for developing appropriate and affordable technologies for waste and drinking water treatments, and long-term decision making policy against water quality management. Traditional water treatment technologies are generally chemical-intensive processes requiring extremely large infrastructural support thus limiting their effective applications in developing nations which creates an artificial barrier to the application of technological solutions for the provision of clean water. Nanotechnology-based systems are in retrospect, smaller, energy and resource efficient. Economic impact assessment of the implementation of nanotechnology in water treatment and studies on cost-effectiveness and environmental and social impacts is of key importance prior to its wide spread acceptance. Government agencies and inter-governmental bodies driving research and development activities need to measure the effective potential of nanotechnology as a solution to global water challenges in order to effectively engage in fiscal, economic and social issues at national and international levels for different types of source waters with new national and international initiatives on nanotechnology and water need to be launched. Environmental pollution and industrialization in global scale is further leading to pollution of available water sources and thus hygienically friendly purification technologies are the need of the hour. Thus cost-effective treatment of pollutants for the transformation of hazardous

  2. A potential model for sodium chloride solutions based on the TIP4P/2005 water model

    Science.gov (United States)

    Benavides, A. L.; Portillo, M. A.; Chamorro, V. C.; Espinosa, J. R.; Abascal, J. L. F.; Vega, C.

    2017-09-01

    Despite considerable efforts over more than two decades, our knowledge of the interactions in electrolyte solutions is not yet satisfactory. Not even one of the most simple and important aqueous solutions, NaCl(aq), escapes this assertion. A requisite for the development of a force field for any water solution is the availability of a good model for water. Despite the fact that TIP4P/2005 seems to fulfill the requirement, little work has been devoted to build a force field based on TIP4P/2005. In this work, we try to fill this gap for NaCl(aq). After unsuccessful attempts to produce accurate predictions for a wide range of properties using unity ionic charges, we decided to follow recent suggestions indicating that the charges should be scaled in the ionic solution. In this way, we have been able to develop a satisfactory non-polarizable force field for NaCl(aq). We evaluate a number of thermodynamic properties of the solution (equation of state, maximum in density, enthalpies of solution, activity coefficients, radial distribution functions, solubility, surface tension, diffusion coefficients, and viscosity). Overall the results for the solution are very good. An important achievement of our model is that it also accounts for the dynamical properties of the solution, a test for which the force fields so far proposed failed. The same is true for the solubility and for the maximum in density where the model describes the experimental results almost quantitatively. The price to pay is that the model is not so good at describing NaCl in the solid phase, although the results for several properties (density and melting temperature) are still acceptable. We conclude that the scaling of the charges improves the overall description of NaCl aqueous solutions when the polarization is not included.

  3. Selected specific rates of reactions of transients from water in aqueous solution. II. Hydrogen atom

    International Nuclear Information System (INIS)

    Anbar, M.; Farhataziz; Ross, A.B.

    1975-05-01

    Rates of reactions of hydrogen atoms (from radiolysis of water and other sources) with organic and inorganic molecules, ions, and transients in aqueous solution were tabulated. Directly measured rates obtained by kinetic spectroscopy or conductimetric methods, and relative rates determined by competition kinetics are included. (U.S.)

  4. A Comparison of Numerical and Analytical Radiative-Transfer Solutions for Plane Albedo in Natural Waters

    Science.gov (United States)

    Several numerical and analytical solutions of the radiative transfer equation (RTE) for plane albedo were compared for solar light reflection by sea water. The study incorporated the simplest case, that being a semi-infinite one-dimensional plane-parallel absorbing and scattering...

  5. Water, solute and heat transport in the soil: the Australian connection

    Science.gov (United States)

    Knight, John

    2016-04-01

    The interest of Peter Raats in water, solute and heat transport in the soil has led to scientific and/or personal interactions with several Australian scientists such as John Philip, David Smiles, Greg Davis and John Knight. Along with John Philip and Robin Wooding, Peter was an early user of the Gardner (1958) linearised model of soil water flow, which brought him into competition with John Philip. I will discuss some of Peter's solutions relevant to infiltration from line and point sources, cavities and basins. A visit to Canberra, Australia in the early 1980s led to joint work on soil water flow, and on combined water and solute movement with David Smiles and others. In 1983 Peter was on the PhD committee for Greg Davis at the University of Wollongong, and some of the methods in his thesis 'Mathematical modelling of rate-limiting mechanisms of pyritic oxidation in overburden dumps' were later used by Peter's student Sjoerd van der Zee. David Smiles and Peter wrote a survey article 'Hydrology of swelling clay soils' in 2005. In the last decade Peter has been investigating the history of groundwater and vadose zone hydrology, and recently he and I have been bringing to light the largely forgotten work of Lewis Fry Richardson on finite difference solution of the heat equation, drainage theory, soil physics, and the soil-plant-atmosphere continuum.

  6. Accounting for multiple functions in environmental life cycle assessment of storm water management solutions

    DEFF Research Database (Denmark)

    Brudler, Sarah; Arnbjerg-Nielsen, Karsten; Rygaard, Martin

    The wide range of approaches to handle storm water runoff have varying effects on the environment. Local stormwater control measures for retention and treatment are increasingly used components in urban climate adaptation plans. Often, these solutions modify the multiple functions of urban...

  7. Forward and pressure retarded osmosis: potential solutions for global challenges in energy and water supply.

    Science.gov (United States)

    Klaysom, Chalida; Cath, Tazhi Y; Depuydt, Tom; Vankelecom, Ivo F J

    2013-08-21

    Osmotically driven membrane processes (ODMP) have gained renewed interest in recent years and they might become a potential solution for the world's most challenging problems of water and energy scarcity. Though the concept of utilizing osmotic pressure difference between high and low salinity streams across semipermeable membranes has been explored for several decades, lack of optimal membranes and draw solutions hindered competition between forward osmosis (FO) and pressure retarded osmosis (PRO) with existing water purification and power generation technologies, respectively. Driven by growing global water scarcity and by energy cost and negative environmental impacts, novel membranes and draw solutions are being developed for ODMPs, mass and heat transfer in osmotic process are becoming better understood, and new applications of ODMPs are emerging. Therefore, OMDPs might become promising green technologies to provide clean water and clean energy from abundantly available renewable resources. This review focuses primarily on new insights into osmotic membrane transport mechanisms and on novel membranes and draw solutions that are currently being developed. Furthermore, the effects of operating conditions on the overall performance of osmotic membranes will be highlighted and future perspectives will be presented.

  8. Solubility of corrosion products of plain steel in oxygen-containing water solutions at high parameters

    International Nuclear Information System (INIS)

    Martynova, O.I.; Samojlov, Yu.F.; Petrova, T.I.; Kharitonova, N.L.

    1983-01-01

    Technique for calculation of solubility of iron corrosion products in oxygen-containing aqueous solutions in the 298-573 K temperature range is presented. Solubility of corrosion products of plain steel in deeply-desalinizated water in the presence of oxygen for the such range of the temperatures is experimentally determined. Rather good convergence between calculated and experimental data is noted

  9. Influence of water and salt solutions on UVB irradiation of normal skin and psoriasis

    International Nuclear Information System (INIS)

    Boer, J.; Schothorst, A.A.; Boom, B.; Suurmond, D.; Hermans, J.

    1982-01-01

    The influence of tap-water (TW) and salt solutions on the minimal erythema dose (MED) was investigated for normal human skin and uninvolved skin of psoriasis patients. MED (UVB) determinations on the forearm revealed that: (1) the MED definitely decreases whenever the arm is immersed in TW or NaCl solutions with a low concentration (4%) prior to UVB exposure, whereas almost saturated NaCl solution (26%), as well as locum Dead Sea water (LDSW), do not produce a change in the MED, and (2) the decrease in MED obtained by wetting the skin with TW was no longer present when the skin was allowed to dry for 20 min. A decrease in water uptake by skin (in vivo) and by callus (in vitro) was found as the salt concentration of the external solution increased. It is proposed that water taken up by the skin plays an important role in the sensitivity of the skin to UVB exposure. Bathing in TW or 4% NaCl prior to UVB exposure offered a slight to moderate improvement in psoriasis over UVB irradiation alone. Finally, it was shown that there is no obvious difference in clearance of the psoriatic skin between a bath in TW, 4% NaCl, or LDSW prior to UVB exposure. (orig.)

  10. Kinetics of reactions of aquacobalamin with aspartic and glutamic acids and their amides in water solutions

    Science.gov (United States)

    Bui, T. T. T.; Sal'nikov, D. S.; Dereven'kov, I. A.; Makarov, S. V.

    2017-04-01

    The kinetics of aquacobalamin reaction with aspartic and glutamic acids, and with their amides in water solutions, is studied via spectrophotometry. The kinetic and activation parameters of the process are determined. It is shown that the reaction product is cobalamin-amino acid complex. The data are compared to results on the reaction between aquacobalamin and primary amines.

  11. The solution of the dam-break problem in the Porous Shallow water Equations

    Science.gov (United States)

    Cozzolino, Luca; Pepe, Veronica; Cimorelli, Luigi; D'Aniello, Andrea; Della Morte, Renata; Pianese, Domenico

    2018-04-01

    The Porous Shallow water Equations are commonly used to evaluate the propagation of flooding waves in the urban environment. These equations may exhibit not only classic shocks, rarefactions, and contact discontinuities, as in the ordinary two-dimensional Shallow water Equations, but also special discontinuities at abrupt porosity jumps. In this paper, an appropriate parameterization of the stationary weak solutions of one-dimensional Porous Shallow water Equations supplies the inner structure of the porosity jumps. The exact solution of the corresponding dam-break problem is presented, and six different wave configurations are individuated, proving that the solution exists and it is unique for given initial conditions and geometric characteristics. These results can be used as a benchmark in order to validate one- and two-dimensional numerical models for the solution of the Porous Shallow water Equations. In addition, it is presented a novel Finite Volume scheme where the porosity jumps are taken into account by means of a variables reconstruction approach. The dam-break results supplied by this numerical scheme are compared with the exact dam-break results, showing the promising capabilities of this numerical approach. Finally, the advantages of the novel porosity jump definition are shown by comparison with other definitions available in the literature, demonstrating its advantages, and the issues raising in real world applications are discussed.

  12. Ice crystallization in ultrafine water-salt aerosols: nucleation, ice-solution equilibrium, and internal structure.

    Science.gov (United States)

    Hudait, Arpa; Molinero, Valeria

    2014-06-04

    Atmospheric aerosols have a strong influence on Earth's climate. Elucidating the physical state and internal structure of atmospheric aqueous aerosols is essential to predict their gas and water uptake, and the locus and rate of atmospherically important heterogeneous reactions. Ultrafine aerosols with sizes between 3 and 15 nm have been detected in large numbers in the troposphere and tropopause. Nanoscopic aerosols arising from bubble bursting of natural and artificial seawater have been identified in laboratory and field experiments. The internal structure and phase state of these aerosols, however, cannot yet be determined in experiments. Here we use molecular simulations to investigate the phase behavior and internal structure of liquid, vitrified, and crystallized water-salt ultrafine aerosols with radii from 2.5 to 9.5 nm and with up to 10% moles of ions. We find that both ice crystallization and vitrification of the nanodroplets lead to demixing of pure water from the solutions. Vitrification of aqueous nanodroplets yields nanodomains of pure low-density amorphous ice in coexistence with vitrified solute rich aqueous glass. The melting temperature of ice in the aerosols decreases monotonically with an increase of solute fraction and decrease of radius. The simulations reveal that nucleation of ice occurs homogeneously at the subsurface of the water-salt nanoparticles. Subsequent ice growth yields phase-segregated, internally mixed, aerosols with two phases in equilibrium: a concentrated water-salt amorphous mixture and a spherical cap-like ice nanophase. The surface of the crystallized aerosols is heterogeneous, with ice and solution exposed to the vapor. Free energy calculations indicate that as the concentration of salt in the particles, the advance of the crystallization, or the size of the particles increase, the stability of the spherical cap structure increases with respect to the alternative structure in which a core of ice is fully surrounded by

  13. MARSOL: Demonstrating Managed Aquifer Recharge as a Solution to Water Scarcity and Drought

    Science.gov (United States)

    Schueth, Christoph

    2014-05-01

    Southern Europe and the Mediterranean region are facing the challenge of managing its water resources under conditions of increasing scarcity and concerns about water quality. Already, the availability of fresh water in sufficient quality and quantity is one of the major factors limiting socio economic development. Innovative water management strategies such as the storage of reclaimed water or excess water from different sources in Managed Aquifer Recharge (MAR) schemes can greatly increase water availability and therefore improve water security. Main objective of the proposed project MARSOL is to demonstrate that MAR is a sound, safe and sustainable strategy that can be applied with great confidence and therefore offering a key approach for tackling water scarcity in Southern Europe. For this, eight field sites were selected that will demonstrate the applicability of MAR using various water sources, ranging from treated wastewater to desalinated seawater, and a variety of technical solutions. Targets are the alleviation of the effect of climate change on water resources, the mitigation of droughts, to countermeasure temporal and spatial misfit of water availability, to sustain agricultural water supply and rural socio-economic development, to combat agricultural related pollutants, to sustain future urban and industrial water supply and to limit seawater intrusion in coastal aquifers. Results of the demonstration sites will be used to develop guidelines for MAR site selection, technical realization, monitoring strategies, and modeling approaches, to offer stakeholders a comprehensive, state of the art and proven toolbox for MAR implementation. Further, the economic and legal aspects of MAR will be analyzed to enable and accelerate market penetration. The MARSOL consortium combines the expertise of consultancies, water suppliers, research institutions, and public authorities, ensuring high practical relevance and market intimacy.

  14. [Ultrasound induced the formation of nitric oxide and nitrosonium ions in water and aqueous solutions].

    Science.gov (United States)

    Stepuro, I I; Adamchuk, R I; Stepuro, V I

    2004-01-01

    Nitric oxide, nitrosonium ions, nitrites, and nitrates are formed in water saturated with air under the action of ultrasound. Nitrosonium ions react with water and hydrogen peroxide to form nitrites and nitrates in sonicated solution, correspondingly. Nitric oxide is practically completely released from sonicated water into the atmosphere and reacts with air oxygen, forming NOx compounds. The oxidation of nitric oxide in aqueous medium by hydroxyl radicals and dissolved oxygen is a minor route of the formation of nitrites and nitrates in ultrasonic field.

  15. Multiphase flow experiments, mathematical modeling and numerical simulation of the water - gas - solute movement

    Science.gov (United States)

    Li, Y.; Ma, X.; Su, N.

    2013-12-01

    The movement of water and solute into and through the vadose zone is, in essence, an issue of immiscible displacement in pore-space network of a soil. Therefore, multiphase flow and transport in porous media, referring to three medium: air, water, and the solute, pose one of the largest unresolved challenges for porous medium fluid seepage. However, this phenomenon has always been largely neglected. It is expected that a reliable analysis model of the multi-phase flow in soil can truly reflect the process of natural movement about the infiltration, which is impossible to be observed directly. In such cases, geophysical applications of the nuclear magnetic resonance (NMR) provides the opportunity to measure the water movements into soils directly over a large scale from tiny pore to regional scale, accordingly enable it available both on the laboratory and on the field. In addition, the NMR provides useful information about the pore space properties. In this study, we proposed both laboratory and field experiments to measure the multi-phase flow parameters, together with optimize the model in computer programming based on the fractional partial differential equations (fPDE). In addition, we establish, for the first time, an infiltration model including solute flowing with water, which has huge influence on agriculture and soil environment pollution. Afterwards, with data collected from experiments, we simulate the model and analyze the spatial variability of parameters. Simulations are also conducted according to the model to evaluate the effects of airflow on water infiltration and other effects such as solute and absorption. It has significant meaning to oxygen irrigation aiming to higher crop yield, and shed more light into the dam slope stability. In summary, our framework is a first-time model added in solute to have a mathematic analysis with the fPDE and more instructive to agriculture activities.

  16. Modeling water flow and solute transport in unsaturated zone inside NSRAWD project

    International Nuclear Information System (INIS)

    Constantin, A.; Diaconu, D.; Bucur, C.; Genty, A.

    2015-01-01

    The NSRAWD project (2010-2013) - Numerical Simulations for Radioactive Waste Disposal was initiated under a collaboration agreement between the Institute for Nuclear Research and the French Alternative Energies and Atomic Energy Commission (CEA). The context of the project was favorable to combine the modeling activities with an experimental part in order to improve and validate the numerical models used so far to simulate water flow and solute transport at Saligny site, Romania. The numerical models developed in the project were refined and validated on new hydrological data gathered between 2010-2012 by a monitoring station existent on site which performs automatic determination of soil water content and matrix potential, as well as several climate parameters (wind, temperature and precipitations). Water flow and solute transport was modeled in transient conditions, by taking into consideration, as well as neglecting the evapotranspiration phenomenon, on the basis of a tracer test launched on site. The determination of dispersivities for solute transport was targeted from the solute plume. The paper presents the main results achieved in the NSRAWD project related to water flow and solute transport in the unsaturated area of the Saligny site. The results indicated satisfactory predictions for the simulation of water flow in the unsaturated area, in steady state and transient conditions. In the case of tracer transport modeling, dispersivity coefficients could not be finally well fitted for the data measured on site and in order to obtain a realistic preview over the values of these parameters, further investigations are recommended. The article is followed by the slides of the presentation

  17. Waters associated with an active basaltic volcano, Kilauea, Hawaii: Variation in solute sources, 1973-1991

    Science.gov (United States)

    Tilling, R.I.; Jones, B.F.

    1996-01-01

    Chemical and isotopic analyses of samples collected from a 1262-m-deep research borehole at the summit of Kilauea Volcano provide unique time-series data for composition of waters in the uppermost part of its hydrothermal system. These waters have a distinctive geochemical signature: a very low proportion of chloride relative to other anions compared with other Hawaiian wa-ters - thermal (???30 ??C) or nonthermal (eruption (December 31, 1974) and associated intense seismicity. Following the initial sharp increase, the PCO2 then decreased, approaching preemption values in April 1976. Beginning in mid-1975, solute concentrations of the borehole waters decreased substantially, from ???45 meq/L to <25 meq/L in only eight months; by 1991, total solute concentrations were <17 meq/L. This decline in solutes cannot be attributed to rainfall dilution and is inferred to reflect the decreasing availability with time of the easily leachable salts of alkali metals and sulfate, which originated in sublimates and fumarolic encrustations in fractures and cavities of rocks along the hydrologic flow paths. The overall chemistry of the summit-borehole waters is largely determined by hydrolysis reactions associated with normal weathering of host tholeiitic basalts on a geologic time scale, despite short-term perturbations in composition caused by rainfall dilution or volcanic activity.

  18. Accelerating the Integration of Distributed Water Solutions: A Conceptual Financing Model from the Electricity Sector

    Science.gov (United States)

    Quesnel, Kimberly J.; Ajami, Newsha K.; Wyss, Noemi

    2017-11-01

    Modern challenges require new approaches to urban water management. One solution in the portfolio of potential strategies is the integration of distributed water infrastructure, practices, and technologies into existing systems. However, many practical barriers have prevented the widespread adoption of these systems in the US. The objective of this paper is to address these challenges by developing a conceptual model encompassing regulatory, financial, and governance components that can be used to incorporate new distributed water solutions into our current network. To construct the model, case studies of successfully implemented distributed electricity systems, specifically energy efficiency and renewable energy technologies, were examined to determine how these solutions have become prominent in recent years and what lessons can be applied to the water sector in a similar pursuit. The proposed model includes four action-oriented elements: catalyzing change, establishing funding sources, using resource pathways, and creating innovative governance structures. As illustrated in the model, the water sector should use suite of coordinated policies to promote change, engage end users through fiscal incentives, and encourage research, development and dissemination of new technologies over time.

  19. Molecular Dynamics and Neutron Scattering Studies of Mixed Solutions of Caffeine and Pyridine in Water.

    Science.gov (United States)

    Tavagnacco, Letizia; Mason, Philip E; Neilson, George W; Saboungi, Marie-Louise; Cesàro, Attilio; Brady, John W

    2018-05-31

    Insight into the molecular interactions of homotactic and heterotactic association of caffeine and pyridine in aqueous solution is given on the basis of both experimental and simulation studies. Caffeine is about 5 times more soluble in a 3 m aqueous pyridine solution than it is in pure water (an increase from ∼0.1 m to 0.5 m). At this elevated concentration the system becomes suitable for neutron scattering study. Caffeine-pyridine interactions were studied by neutron scattering and molecular dynamics simulations, allowing a detailed characterization of the spatial and orientational structure of the solution. It was found that while pyridine-caffeine interactions are not as strong as caffeine-caffeine interactions, the pyridine-caffeine interactions still significantly disrupted caffeine-caffeine stacking. The alteration of the caffeine-caffeine stacking, occasioned by the presence of pyridine molecules in solution and the consequent formation of heterotactic interactions, leads to the experimentally detected increase in caffeine solubility.

  20. Water activity of aqueous solutions of ethylene oxide-propylene oxide block copolymers and maltodextrins

    Directory of Open Access Journals (Sweden)

    N. D. D. Carareto

    2010-03-01

    Full Text Available The water activity of aqueous solutions of EO-PO block copolymers of six different molar masses and EO/PO ratios and of maltodextrins of three different molar masses was determined at 298.15 K. The results showed that these aqueous solutions present a negative deviation from Raoult's law. The Flory-Huggins and UNIFAC excess Gibbs energy models were employed to model the experimental data. While a good agreement was obtained with the Flory-Huggins equation, discrepancies were observed when predicting the experimental behavior with the UNIFAC model. The water activities of ternary systems formed by a synthetic polymer, maltodextrin and water were also measured and used to test the predictive capability of both models.

  1. Regularities of thermochemical characteristics of 1-1, 2-1, 3-1 electrolyte solutions in dimethyl sulfoxide-water and propylene carbonate water mixtures

    International Nuclear Information System (INIS)

    Vorob'ev, A.F.; Monaenkova, A.S.; AlekseeV, G.I.

    1987-01-01

    In an air-tight tilting calorimeter with an isothermal casing enthalpies of praseodymium chloride solution in water, dimethyl sulfoxide (DMSO) - water mixtures, contaning 3.86 and 18.53 mol.% DMSO, and propylene carbonate (PC) - water mixtures, containing 1.85 and 3.23 mol.% PC are measured. The enthalpies of praseodymium chloride solution in the given mixtures in case of infinite solution dilution are determined. Solvation enthalpies of praseodymium and neodymium chlorides, as well as alkali earth metal and magnesium chlorides in water and DMSO - water and PC - water mixtures are calculated. Regularities in thermochemical characteristics of solutions of the given salts in DMSO - water and PC - water mixtures are discussed

  2. Supercooling of aqueous dimethylsulfoxide solution at normal and high pressures: Evidence for the coexistence of phase-separated aqueous dimethylsulfoxide solutions of different water structures

    Science.gov (United States)

    Kanno, H.; Kajiwara, K.; Miyata, K.

    2010-05-01

    Supercooling behavior of aqueous dimethylsulfoxide (DMSO) solution was investigated as a function of DMSO concentration and at high pressures. A linear relationship was observed for TH (homogeneous ice nucleation temperature) and Tm (melting temperature) for the supercooling of aqueous DMSO solution at normal pressure. Analysis of the DTA (differential thermal analysis) traces for homogeneous ice crystallization in the bottom region of the TH curve for a DMSO solution of R =20 (R: moles of water/moles of DMSO) at high pressures supported the contention that the second critical point (SCP) of liquid water should exist at Pc2=˜200 MPa and at Tc2pressure of SCP, Tc2: temperature of SCP). The presence of two TH peaks for DMSO solutions (R =15, 12, and 10) suggests that phase separation occurs in aqueous DMSO solution (R ≤15) at high pressures and low temperatures (pressure dependence of the two TH curves for DMSO solutions of R =10 and 12 indicates that the two phase-separated components in the DMSO solution of R =10 have different liquid water structures [LDL-like and HDL-like structures (LDL: low-density liquid water, HDL: high-density liquid water)] in the pressure range of 120-230 MPa.

  3. The vapour pressure of water as a function of solute concentration above aqueous solutions of fructose, sucrose, raffinose, erythritol, xylitol, and sorbitol

    DEFF Research Database (Denmark)

    Cooke, S.A.; Jonsdottir, Svava Osk; Westh, Peter

    2002-01-01

    The vapour pressure of water above an aqueous solution of sucrose at T = 298.06 K has been measured for 9 sucrose mole fractions up to 0.12. Vapour pressure measurements have also been made on aqueous solutions of meso-erythritol, xylitol, sorbitol, fructose, and raffinose at T = 317.99 K...

  4. Improved prediction of octanol-water partition coefficients from liquid-solute water solubilities and molar volumes

    Science.gov (United States)

    Chiou, C.T.; Schmedding, D.W.; Manes, M.

    2005-01-01

    A volume-fraction-based solvent-water partition model for dilute solutes, in which the partition coefficient shows a dependence on solute molar volume (V??), is adapted to predict the octanol-water partition coefficient (K ow) from the liquid or supercooled-liquid solute water solubility (Sw), or vice versa. The established correlation is tested for a wide range of industrial compounds and pesticides (e.g., halogenated aliphatic hydrocarbons, alkylbenzenes, halogenated benzenes, ethers, esters, PAHs, PCBs, organochlorines, organophosphates, carbamates, and amidesureas-triazines), which comprise a total of 215 test compounds spanning about 10 orders of magnitude in Sw and 8.5 orders of magnitude in Kow. Except for phenols and alcohols, which require special considerations of the Kow data, the correlation predicts the Kow within 0.1 log units for most compounds, much independent of the compound type or the magnitude in K ow. With reliable Sw and V data for compounds of interest, the correlation provides an effective means for either predicting the unavailable log Kow values or verifying the reliability of the reported log Kow data. ?? 2005 American Chemical Society.

  5. Small hydropower plant in Ruetenen - Drainage water utilization from the Alpine motor way tunnel 'Seelisberg' in Switzerland

    International Nuclear Information System (INIS)

    Odermatt, K.; Ettlin, M.

    2001-01-01

    This report for the Swiss Federal Office of Energy (SFOE) describes a project that uses the drainage water from the Seelisberg motor way tunnel in central Switzerland to drive a small turbine that uses the fall distance between the collection point near the tunnel portal and the lake of Lucerne, which lies 48 meters below, to generate more than 100 kW of electrical power. The operation of the hydraulic power station and the experience gained during initial operation are described and the somewhat erratic amounts of water - depending on rainfall, snow-melting etc. - are discussed. Figures are given on the building and operational costs, electricity production and the price of the electricity produced. The report is illustrated with technical drawings and photos of the installation

  6. Using UCST ionic liquid as a draw solute in forward osmosis to treat high-salinity water

    KAUST Repository

    Zhong, Yujiang

    2015-12-09

    The concept of using a thermo-responsive ionic liquid (IL) with an upper critical solution temperature (UCST) as a draw solute in forward osmosis (FO) was successfully demonstrated here experimentally. A 3.2 M solution of protonated betaine bis(trifluoromethylsulfonyl)imide ([Hbet][Tf2N]) was obtained by heating and maintaining the temperature above 56°C. This solution successfully drew water from high-salinity water up to 3.0 M through FO. When the IL solution cooled to room temperature, it spontaneously separated into a water-rich phase and an IL-rich phase: the water-rich phase was the produced water that contained a low IL concentration, and the IL-rich phase could be used directly as the draw solution in the next cycle of the FO process. The thermal stability, thermal-responsive solubility and UV-vis absorption spectra of the IL were also studied in detail.

  7. Multiobjective optimization of urban water resources: Moving toward more practical solutions

    Science.gov (United States)

    Mortazavi, Mohammad; Kuczera, George; Cui, Lijie

    2012-03-01

    The issue of drought security is of paramount importance for cities located in regions subject to severe prolonged droughts. The prospect of "running out of water" for an extended period would threaten the very existence of the city. Managing drought security for an urban water supply is a complex task involving trade-offs between conflicting objectives. In this paper a multiobjective optimization approach for urban water resource planning and operation is developed to overcome practically significant shortcomings identified in previous work. A case study based on the headworks system for Sydney (Australia) demonstrates the approach and highlights the potentially serious shortcomings of Pareto optimal solutions conditioned on short climate records, incomplete decision spaces, and constraints to which system response is sensitive. Where high levels of drought security are required, optimal solutions conditioned on short climate records are flawed. Our approach addresses drought security explicitly by identifying approximate optimal solutions in which the system does not "run dry" in severe droughts with expected return periods up to a nominated (typically large) value. In addition, it is shown that failure to optimize the full mix of interacting operational and infrastructure decisions and to explore the trade-offs associated with sensitive constraints can lead to significantly more costly solutions.

  8. EXPERIENCE OF SEA WATER HYPERTONIC SOLUTION APPLICATION FOR TOPICAL TREATMENT OF CHRONIC TONSILLITIS

    Directory of Open Access Journals (Sweden)

    E.P. Karpova

    2006-01-01

    Full Text Available The study examined the effectiveness of sea water hypertonic solution (Aqua Maris troath and oral cavity spray, Jadran, Croatia medication to treat chronic tonsillitis of the compensated form on 84 children aged between 5 and 15. All children had their tonsil lacunae rinsed in a day № 6–8. 64 children had them rinsed with the sea water hypertonic solution (main group, while 20 children had them rinsed with the nitrofural solution (comparison group. Treatment effectiveness was determined according to dynamics of main symptoms (odynophagia, dysphagia, hyperemia and mucosa infiltration of pillars of the fauces, as well as the degree of tonsil bacterial number before and after treatment (by the 14th day. The dynamic analysis of subjective data during treatment revealed more significant and positive changes among the children of the main group if compared with patients from the comparison group. After treatment the researchers noticed reduction of tonsil bacterial number among 90,62% of children from the main group, whereas this rate made up 60% in the comparison group. Acquired data allowed recommending this medication for the multimodality therapy of infant adenoid disease.Key words: chronic tonsillitis, treatment, children, sea water hypertonic solution.

  9. The role of water in cholinium carboxylate ionic liquid’s aqueous solutions

    International Nuclear Information System (INIS)

    Patinha, David J.S.; Tomé, Liliana C.; Garcia, Helga; Ferreira, Rui; Pereira, Cristina Silva; Rebelo, Luís Paulo N.; Marrucho, Isabel M.

    2015-01-01

    Highlights: • Densities and viscosities of aqueous solutions of cholinium carboxylate ionic liquids. • 1 H NMR experiments were used to probe nanoscale organization of ionic liquids in water. • Different nanoscale organization in water for the 3 ionic liquids. - Abstract: Binary systems composed of water and cholinium carboxylate ionic liquids, namely cholinium lactate ([Ch][Lac]), cholinium propanoate ([Ch][Prop]) and cholinium malonate ([Ch][Mal]) were studied from the neat ionic liquid to very diluted aqueous solutions. Densities and viscosities were measured and atypical behaviors were observed, such as the increasing density of the binary [Ch][Prop] + H 2 O mixtures with increasing water content. In order to get molecular level insights on the IL + H 2 O solvation schemes, 1 H NMR studies were performed. Large deviations were obtained in the aniońs resonances when compared to those of the cation suggesting that water interacts preferentially with the anion counter-part of the ionic liquid. The increasing density of [Ch][Prop] + H 2 O system with increasing water content can be related to the orientation of the alkyl chains, as a result of their nanoscale organization. This behavior was confirmed through the study of the thermophysical properties of [Ch][Hex] + H 2 O mixtures, where this phenomenon is known to occur

  10. Application of Information Technology Solution for Early Warning Systems at Water Utilities

    Directory of Open Access Journals (Sweden)

    Bałut Alicja

    2018-01-01

    Full Text Available Deployment of IT solutions in water utilities in Poland concerns nowadays lots beyond GIS implementation projects [1]. The scope of modern IT platforms is truly advanced software for complete management of water treatment processes and involved objects, including ranges of various types of equipment. There are multiply factors that disrupt required volumes of supplied water. They are normally classified as natural, accidental and intentional. This paper addresses potential residing in already deployed IT solutions of water utilities in and also in new ones being now developed. Primarily- from the perspective of intentional, terrorist threats. This document depicts operating procedures that are called in case of spotted contamination in a water supply (damage of key elements of the network infrastructure or in case of an introduction factors. This paper also discusses relevant IT tools with access provided to network operators or water plant owners that are extremely useful in accurate pinpointing the treat and in following relevant operating procedures and related actions.

  11. Heterogeneous ice nucleation in aqueous solutions: the role of water activity.

    Science.gov (United States)

    Zobrist, B; Marcolli, C; Peter, T; Koop, T

    2008-05-01

    Heterogeneous ice nucleation experiments have been performed with four different ice nuclei (IN), namely nonadecanol, silica, silver iodide and Arizona test dust. All IN are either immersed in the droplets or located at the droplets surface. The IN were exposed to various aqueous solutions, which consist of (NH4)2SO4, H2SO4, MgCl2, NaCl, LiCl, Ca(NO3)2, K2CO3, CH3COONa, ethylene glycol, glycerol, malonic acid, PEG300 or a NaCl/malonic acid mixture. Freezing was studied using a differential scanning calorimeter and a cold finger cell. The results show that the heterogeneous ice freezing temperatures decrease with increasing solute concentration; however, the magnitude of this effect is solute dependent. In contrast, when the results are analyzed in terms of the solution water activity a very consistent behavior emerges: heterogeneous ice nucleation temperatures for all four IN converge each onto a single line, irrespective of the nature of the solute. We find that a constant offset with respect to the ice melting point curve, Deltaaw,het, can describe the observed freezing temperatures for each IN. Such a behavior is well-known for homogeneous ice nucleation from supercooled liquid droplets and has led to the development of water-activity-based ice nucleation theory. The large variety of investigated solutes together with different general types of ice nuclei studied (monolayers, ionic crystals, covalently bound network-forming compounds, and a mixture of chemically different crystallites) underlines the general applicability of water-activity-based ice nucleation theory also for heterogeneous ice nucleation in the immersion mode. Finally, the ice nucleation efficiencies of the various IN, as well as the atmospheric implication of the developed parametrization are discussed.

  12. Don't Cry over Spilled Water: Identifying Risks and Solutions for Produced Water Spills

    Science.gov (United States)

    Shores, Amanda Rose

    Resource requirements and future energy generation requires careful evaluation, particularly due to climate change and water scarcity. This thesis discusses one aspect of energy generation linked to water; oil-and-gas extraction and the large volumes of waste water produced, otherwise known as "produced water". This research focuses on surface spills of produced water, their ramifications, safeguards against groundwater contamination at spill sites and potential remediation strategies. Produced water contains a variety of contaminants that include the group of known toxins, BTEX (benzene, toluene, ethylbenzene and xylene), and high salt concentrations. A combination of factors such as large volumes of generated produced water, the need for storage and transportation across large distances and the toxic-and-mobile nature of produced water constituents creates risks for spills that can pollute groundwater. Spills occur regularly, particularly in Weld County, Colorado, where the demand for natural gas is high. To answer spill-related hypotheses, a multitude of methodology were employed: modeling, greenhouse experimentation, gas chromatography and summarization of spill reports and statistical analyses. Using publically available spill data, this research found that the frequency of oil-and-gas related spills and the average spilled volume has increased in Weld County from 2011-2015. Additionally, the number of spills that have resulted in groundwater contamination has increased in the area. By focusing on the oil-and-gas operators responsible for these spills, a linear relationship was found between the volumes of oil-and-gas produced compared to the volumes of produced-water generated. However, larger oil-and-gas producers did not show a linear relationship between oil-and-gas produced and produced-water generated, such that larger producers were more efficient and generated less water per unit of energy. So while scale-up efficiency seems to exist for produced-water

  13. Transport of water and solutes in wettable and water repellent sandy soils

    NARCIS (Netherlands)

    Ritsema, C.J.; Dekker, L.W.

    1996-01-01

    The research yielded the following conclusions and results: preferential flow can be expected in recently deposited, loosely packed, wettable dune sands; preferential flow is common in most water-repellent sandy soils; distribution flow in topsoils isa process of major importance, resulting in a

  14. Note: Nonpolar solute partial molar volume response to attractive interactions with water.

    Science.gov (United States)

    Williams, Steven M; Ashbaugh, Henry S

    2014-01-07

    The impact of attractive interactions on the partial molar volumes of methane-like solutes in water is characterized using molecular simulations. Attractions account for a significant 20% volume drop between a repulsive Weeks-Chandler-Andersen and full Lennard-Jones description of methane interactions. The response of the volume to interaction perturbations is characterized by linear fits to our simulations and a rigorous statistical thermodynamic expression for the derivative of the volume to increasing attractions. While a weak non-linear response is observed, an average effective slope accurately captures the volume decrease. This response, however, is anticipated to become more non-linear with increasing solute size.

  15. Note: Nonpolar solute partial molar volume response to attractive interactions with water

    Energy Technology Data Exchange (ETDEWEB)

    Williams, Steven M.; Ashbaugh, Henry S., E-mail: hanka@tulane.edu [Department of Chemical and Biomolecular Engineering, Tulane University, New Orleans, Louisiana 70118 (United States)

    2014-01-07

    The impact of attractive interactions on the partial molar volumes of methane-like solutes in water is characterized using molecular simulations. Attractions account for a significant 20% volume drop between a repulsive Weeks-Chandler-Andersen and full Lennard-Jones description of methane interactions. The response of the volume to interaction perturbations is characterized by linear fits to our simulations and a rigorous statistical thermodynamic expression for the derivative of the volume to increasing attractions. While a weak non-linear response is observed, an average effective slope accurately captures the volume decrease. This response, however, is anticipated to become more non-linear with increasing solute size.

  16. On the influence of molecular structure on the conductivity of electrolyte solutions - sodium nitrate in water

    Directory of Open Access Journals (Sweden)

    H. Krienke

    2013-01-01

    Full Text Available Theoretical calculations of the conductivity of sodium nitrate in water are presented and compared with experimental measurements. The method of direct correlation force in the framework of the interionic theory is used for the calculation of transport properties in connection with the associative mean spherical approximation (AMSA. The effective interactions between ions in solutions are derived with the help of Monte Carlo and Molecular Dynamics calculations on the Born-Oppenheimer level. This work is based on earlier theoretical and experimental studies of the structure of concentrated aqueous sodium nitrate solutions.

  17. Randomized cross-over trial of polyethylene glycol electrolyte solution and water for colostomy irrigation.

    Science.gov (United States)

    O'Bichere, Austin; Green, Colin; Phillips, Robin K S

    2004-09-01

    Water for colostomy irrigation is largely absorbed by the colon, which may result in less efficient expulsion of stool. This study compared the outcome of colonic cleansing with water and polyethylene glycol solution. In a cross-over study, 41 colostomy irrigators were randomly assigned to water or polyethylene glycol solution irrigation first and then the other regimen, each for one week. Patients recorded fluid inflow time, total washout time, cramps, leakage episodes, number of stoma pouches used, and satisfaction scores (Visual Analog Scale, 1-10: 1 = poor, and 10 = excellent). The median and interquartile range for each variable was calculated, and the two treatments were compared (Wilcoxon's test). Eight patients failed to complete the study. Thirty-three patients (20 females; mean age, 55 (range, 39-73) years) provided 352 irrigation sessions: water (n = 176), and polyethylene glycol solution (n = 176). Irrigation was performed every 24, 48, and 72 hours by 17, 9, and 7 patients respectively, using 500 ml (n = 1), 750 ml (n = 2), 1,000 ml (n = 16), 1,500 ml (n = 11), 2,000 ml (n = 2), and 3,500 ml (n = 1) of fluid. The median and interquartile range for water vs. polyethylene glycol solution were: fluid inflow time (6 (range, 4.4-10.8) vs. 6.3 (range, 4.1-11) minutes; P = 0.48), total washout time (53 (range, 33-69) vs. 38 (range, 28-55) minutes; P = 0.01), leakage episodes (2.3 (range, 1.7-3.8) vs. 0.7 (range, 0.2-1); P colostomy irrigation.

  18. Modeling of water flow and solute transport in unsaturated heterogeneous fields

    International Nuclear Information System (INIS)

    Bresler, E.; Dagan, G.

    1982-01-01

    A comprehensive model which considers dispersive solute transport, nonsteady moisture flow regimes and complex boundary conditions is described. The main assumptions are: vertical flow; spatial variability which is associated with the saturated hydraulic conductivity K/sub s/ occurs in the horizontal plane, but is constant in the profile, and has a lognormal probability distribution function (PDF); deterministic recharge and solute concentration are applied during infiltration; the soil is at uniform water content and salt concentration prior to infiltration. The problem is to solve, for arbitrary K/sub s/, the Richards' equation of flow simultaneously with the diffusion-convection equation for salt transport, with the boundary and initial conditions appropriate to infiltration-redistribution. Once this is achieved, the expectation and variance of various quantities of interest (solute concentration, moisture content) are obtained by using the statistical averaging procedure and the given PDF of K/sub s/. Since the solution of Richards' equation for the infiltration-redistribution cycle is extremely difficult (for a given K/sub s/), an approxiate solution is derived by using the concept of piston flow type wetting fronts. Similarly, accurate numerical solutions are used as input for the same statistical averaging procedure. The stochastic model is applied to two spatially variable soils by using both accurate numerical solutions and the simplified water and salt transport models. A comparison between the results shows that the approximate simplified models lead to quite accurate values of the expectations and variances of the flow variables for the entire field. It is suggested that in spatially variable fields, stochastic modeling represents the actual flow phenomena realistically, and provides the main statistical moments by using simplified flow models which can be used with confidence in applications

  19. Modeling the effects of different irrigation water salinity on soil water movement, uptake and multicomponent solute transport

    Science.gov (United States)

    Lekakis, E. H.; Antonopoulos, V. Z.

    2015-11-01

    Simulation models can be important tools for analyzing and managing irrigation, soil salinization or crop production problems. In this study a mathematical model that describes the water movement and mass transport of individual ions (Ca2+, Mg2+ and Na+) and overall soil salinity by means of the soil solution electrical conductivity, is used. The mass transport equations of Ca2+, Mg2+ and Na+ have been incorporated as part of the integrated model WANISIM and the soil salinity was computed as the sum of individual ions. The model was calibrated and validated against field data, collected during a three year experiment in plots of maize, irrigated with three different irrigation water qualities, at Thessaloniki area in Northern Greece. The model was also used to evaluate salinization and sodification hazards by the use of irrigation water with increasing electrical conductivity of 0.8, 3.2 and 6.4 dS m-1, while maintaining a ratio of Ca2+:Mg2+:Na+ equal to 3:3:2. The qualitative and quantitative procedures for results evaluation showed that there was good agreement between the simulated and measured values of the water content, overall salinity and the concentration of individual soluble cations, at two soil layers (0-35 and 35-75 cm). Nutrient uptake was also taken into account. Locally available irrigation water (ECiw = 0.8 dS m-1) did not cause soil salinization or sodification. On the other hand, irrigation water with ECiw equal to 3.2 and 6.4 dS m-1 caused severe soil salinization, but not sodification. The rainfall water during the winter seasons was not sufficient to leach salts below the soil profile of 110 cm. The modified version of model WANISIM is able to predict the effects of irrigation with saline waters on soil and plant growth and it is suitable for irrigation management in areas with scarce and low quality water resources.

  20. Glass transition and relaxation dynamics of propylene glycol-water solutions confined in clay

    Science.gov (United States)

    Elamin, Khalid; Björklund, Jimmy; Nyhlén, Fredrik; Yttergren, Madeleine; Mârtensson, Lena; Swenson, Jan

    2014-07-01

    The molecular dynamics of aqueous solutions of propylene glycol (PG) and propylene glycol methylether (PGME) confined in a two-dimensional layer-structured Na-vermiculite clay has been studied by broadband dielectric spectroscopy and differential scanning calorimetry. As typical for liquids in confined geometries the intensity of the cooperative α-relaxation becomes considerably more suppressed than the more local β-like relaxation processes. In fact, at high water contents the calorimetric glass transition and related structural α-relaxation cannot even be observed, due to the confinement. Thus, the intensity of the viscosity related α-relaxation is dramatically reduced, but its time scale as well as the related glass transition temperature Tg are for both systems only weakly influenced by the confinement. In the case of the PGME-water solutions it is an important finding since in the corresponding bulk system a pronounced non-monotonic concentration dependence of the glass transition related dynamics has been observed due to the growth of hydrogen bonded relaxing entities of water bridging between PGME molecules [J. Sjöström, J. Mattsson, R. Bergman, and J. Swenson, Phys. Chem. B 115, 10013 (2011)]. The present results suggest that the same type of structural entities are formed in the quasi-two-dimensional space between the clay platelets. It is also observed that the main water relaxation cannot be distinguished from the β-relaxation of PG or PGME in the concentration range up to intermediate water contents. This suggests that these two processes are coupled and that the water molecules affect the time scale of the β-relaxation. However, this is most likely true also for the corresponding bulk solutions, which exhibit similar time scales of this combined relaxation process below Tg. Finally, it is found that at higher water contents the water relaxation does not merge with, or follow, the α-relaxation above Tg, but instead crosses the

  1. A Facile All-Solution-Processed Surface with High Water Contact Angle and High Water Adhesive Force.

    Science.gov (United States)

    Chen, Mei; Hu, Wei; Liang, Xiao; Zou, Cheng; Li, Fasheng; Zhang, Lanying; Chen, Feiwu; Yang, Huai

    2017-07-12

    A series of sticky superhydrophobicity surfaces with high water contact angle and high water adhesive force is facilely prepared via an all-solution-processed method based on polymerization-induced phase separation between liquid crystals (LCs) and epoxy resin, which produces layers of epoxy microspheres (EMSs) with nanofolds on the surface of a substrate. The morphologies and size distributions of EMSs are confirmed by scanning electron microscopy. Results reveal that the obtained EMS coated-surface exhibits high apparent contact angle of 152.0° and high water adhesive force up to 117.6 μN. By varying the composition of the sample or preparing conditions, the sizes of the produced EMSs can be artificially regulated and, thus, control the wetting properties and water adhesive behaviors. Also, the sticky superhydrophobic surface exhibits excellent chemical stability, as well as long-term durability. Water droplet transportation experiments further prove that the as-made surface can be effectively used as a mechanical hand for water transportation applications. Based on this, it is believed that the simple method proposed in this paper will pave a new way for producing a sticky superhydrophobic surface and obtain a wide range of use.

  2. Comparision of Incidental Reflection From Containerized Maintenance/Housekeeping Solutions and One Inch of Water

    Energy Technology Data Exchange (ETDEWEB)

    Chapman, Bryan Scott [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); MacQuigg, Michael Robert [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Wysong, Andrew Russell [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-12-15

    This document addresses the incidental reflector reactivity worth of containerized maintenance/housekeeping fluids for use in PF-4 at Los Alamos National Laboratory (LANL). The intent of the document is to analyze containerized maintenance/housekeeping fluids which will be analyzed as water that may be present under normal conditions of an operation. The reactivity worth is compared to the reactivity worth due to I-inch of close-fitting 4n water reflection and I-inch of close-fitting radial water reflection. Both have been used to bound incidental reflection by 2-liter bottles in criticality safety evaluations. The conclusion is that, when the maintenance/housekeeping fluids are containerized the reactivity increase from a configuration which is bounding of normal conditions (up to eight bottles modeled with 2-liters of solution at varying diameter) is bound by I-inch of close fitting 4n water relection.

  3. SFG study on potential-dependent structure of water at Pt electrode/electrolyte solution interface

    Energy Technology Data Exchange (ETDEWEB)

    Noguchi, Hidenori; Okada, Tsubasa; Uosaki, Kohei [Physical Chemistry Laboratory, Division of Chemistry, Graduate School of Science, Hokkaido University, Sapporo 060-0810 (Japan)

    2008-10-01

    Structure of water at Pt/electrolyte solution interface was investigated by sum frequency generation (SFG) spectroscopy. Two broad peaks were observed in OH stretching region at ca. 3200 cm{sup -1} and ca. 3400 cm{sup -1}, which are known to be due to the symmetric OH stretching (U{sub 1}) of tetrahedrally coordinated, i.e., strongly hydrogen bonded 'ice-like' water, and the asymmetric OH stretching (U{sub 3}) of water molecules in a more random arrangement, i.e., weakly hydrogen bonded 'liquid-like' water, respectively. The SFG intensity strongly depended on electrode potential. Several possibilities are suggested for the potential dependence of the SFG intensity. (author)

  4. Contribution of the actomyosin motor to the temperature-dependent translational diffusion of water by cytoplasmic streaming in Elodea canadensis cells.

    Science.gov (United States)

    Vorob'ev, V N; Anisimov, A V; Dautova, N R

    2004-12-01

    The extent to which the actomyosin motor responsible for cytoplasmic streaming contributes to the translational diffusion of water in Elodea canadensis cells was studied by a nuclear magnetic resonance (NMR) spin-echo technique. The relative contribution of the actomyosin motor was determined from the corresponding apparent diffusion coefficient by the Einstein-Smolukhovsky relation. It is equal to the difference between the diffusional displacements of the cytoplasmic and the bulk water (deltaX). The NMR data show that the temperature dependence of deltaX is humpshaped, which is characteristic of enzyme reactions. At the same time, the apparent diffusion coefficient of cytoplasmic water increases with an increase in temperature. The most significant contribution of the actomyosin motor to deltaX is observed at temperatures below 20 degrees C. Within the temperature range of 20 to 33 degrees C, deltaX changes only slightly, and a further increase in temperature reduces deltaX to zero.

  5. GENETIC ALGORITHM BASED SOLUTION IN PWM CONVERTER SWITCHING FOR VOLTAGE SOURCE INVERTER FEEDING AN INDUCTION MOTOR DRIVE

    Directory of Open Access Journals (Sweden)

    V. Jegathesan

    2017-11-01

    Full Text Available This paper presents an efficient and reliable Genetic Algorithm based solution for Selective Harmonic Elimination (SHE switching pattern. This method eliminates considerable amount of lower order line voltage harmonics in Pulse Width Modulation (PWM inverter. Determination of pulse pattern for the elimination of some lower order harmonics of a PWM inverter necessitates solving a system of nonlinear transcendental equations. Genetic Algorithm is used to solve nonlinear transcendental equations for PWM-SHE. Many methods are available to eliminate the higher order harmonics and it can be easily removed. But the greatest challenge is to eliminate the lower order harmonics and this is successfully achieved using Genetic Algorithm without using Dual transformer. Simulations using MATLABTM and Powersim with experimental results are carried out to validate the solution. The experimental results show that the harmonics up to 13th were totally eliminated.

  6. Large zero-tension plate lysimeters for soil water and solute collection in undisturbed soils

    Directory of Open Access Journals (Sweden)

    A. Peters

    2009-09-01

    Full Text Available Water collection from undisturbed unsaturated soils to estimate in situ water and solute fluxes in the field is a challenge, in particular if soils are heterogeneous. Large sampling devices are required if preferential flow paths are present. We present a modular plate system that allows installation of large zero-tension lysimeter plates under undisturbed soils in the field. To investigate the influence of the lysimeter on the water flow field in the soil, a numerical 2-D simulation study was conducted for homogeneous soils with uni- and bimodal pore-size distributions and stochastic Miller-Miller heterogeneity. The collection efficiency was found to be highly dependent on the hydraulic functions, infiltration rate, and lysimeter size, and was furthermore affected by the degree of heterogeneity. In homogeneous soils with high saturated conductivities the devices perform poorly and even large lysimeters (width 250 cm can be bypassed by the soil water. Heterogeneities of soil hydraulic properties result into a network of flow channels that enhance the sampling efficiency of the lysimeter plates. Solute breakthrough into zero-tension lysimeter occurs slightly retarded as compared to the free soil, but concentrations in the collected water are similar to the mean flux concentration in the undisturbed soil. To validate the results from the numerical study, a dual tracer study with seven lysimeters of 1.25×1.25 m area was conducted in the field. Three lysimeters were installed underneath a 1.2 m filling of contaminated silty sand, the others deeper in the undisturbed soil. The lysimeters directly underneath the filled soil material collected water with a collection efficiency of 45%. The deeper lysimeters did not collect any water. The arrival of the tracers showed that almost all collected water came from preferential flow paths.

  7. Using UCST ionic liquid as a draw solute in forward osmosis to treat high-salinity water

    KAUST Repository

    Zhong, Yujiang; Feng, Xiaoshuang; Chen, Wei; Wang, Xinbo; Huang, Kuo-Wei; Gnanou, Yves; Lai, Zhiping

    2015-01-01

    (trifluoromethylsulfonyl)imide ([Hbet][Tf2N]) was obtained by heating and maintaining the temperature above 56°C. This solution successfully drew water from high-salinity water up to 3.0 M through FO. When the IL solution cooled to room temperature, it spontaneously separated into a

  8. Probing ion-specific effects on aqueous acetate solutions: Ion pairing versus water structure modifications.

    Science.gov (United States)

    Petit, Tristan; Lange, Kathrin M; Conrad, Gerrit; Yamamoto, Kenji; Schwanke, Christoph; Hodeck, Kai F; Dantz, Marcus; Brandenburg, Tim; Suljoti, Edlira; Aziz, Emad F

    2014-05-01

    The effect of monovalent cations (Li(+), K(+), NH4 (+), Na(+)) on the water structure in aqueous chloride and acetate solutions was characterized by oxygen K-edge X-ray absorption spectroscopy (XAS), X-ray emission spectroscopy, and resonant inelastic X-ray scattering (RIXS) of a liquid microjet. We show ion- and counterion dependent effects on the emission spectra of the oxygen K-edge, which we attribute to modifications of the hydrogen bond network of water. For acetates, ion pairing with carboxylates was also probed selectively by XAS and RIXS. We correlate our experimental results to speciation data and to the salting-out properties of the cations.

  9. Recovery of uranium from uranium mine waters and copper ore leaching solutions

    Energy Technology Data Exchange (ETDEWEB)

    George, D R; Ross, J R [Salt Lake City Metallurgy Research Center, Salt Lake City, UT (United States)

    1967-06-15

    Waters pumped from uranium mines in New Mexico are processed by ion exchange to recover uranium. Production is approximately 200 lb U{sub 3}O{sub 8}/d from waters containing 5 to 15 ppm U{sub 3}O{sub 8}. Recoveries range from 80 to 90%. Processing plants are described. Uranium has been found in the solutions resulting from the leaching of copper-bearing waste rock at most of the major copper mines in western United States. These solutions, which are processed on a very large scale for recovery of copper, contain 2 to 12 ppm U{sub 3}O{sub 8}. Currently, uranium is not being recovered, but a potential production of up to 6000 lb U{sub 3}O{sub 8}/d is indicated. Ion exchange and solvent extraction research studies are described. (author)

  10. Distribution of trace elements between clays and zeolites and aqueous solutions similar to sea water

    International Nuclear Information System (INIS)

    Berger, G.

    1992-01-01

    The mechanisms of solid-solution partitioning during mineral crystallization in sea water have been investigated for Rb, Cs, Co, Sr, U, Th and lanthanides as trace elements, and Fe, Mg-chlorite/smectites and Na-zeolites as solid phases. These minerals have been synthesized by alteration at 40 o C in saline solutions of silicate glasses of appropriate compositions. The variation of the distribution coefficients (D) with the concentration of the elements as well as competition mechanisms between elements of analogous crystallochemical properties have been studied. The ''trapping'' of trace elements is shown to be governed by two mechanisms, according to D values or to water-rock ratios. At low values of D the incorporation of elements is controlled only by D, whereas at high values it is controlled by the number of available crystallochemical sites. (Author)

  11. Biologically Pre-Treated Habitation Waste Water as a Sustainable Green Urine Pre-Treat Solution

    Science.gov (United States)

    Jackson, W. Andrew; Thompson, Bret; Sevanthi, Ritesh; Morse, Audra; Meyer, Caitlin; Callahan, Michael

    2017-01-01

    The ability to recover water from urine and flush water is a critical process to allow long term sustainable human habitation in space or bases on the moon or mars. Organic N present as urea or similar compounds can hydrolyze producing free ammonia. This reaction results in an increase in the pH converting ammonium to ammonia which is volatile and not removed by distillation. The increase in pH will also cause precipitation reactions to occur. In order to prevent this, urine on ISS is combined with a pretreat solution. While use of a pretreatment solution has been successful, there are numerous draw backs including: storage and use of highly hazardous solutions, limitations on water recovery (less than 85%), and production of brine with pore dewatering characteristics. We evaluated the use of biologically treated habitation wastewaters (ISS and early planetary base) to replace the current pretreat solution. We evaluated both amended and un-amended bioreactor effluent. For the amended effluent, we evaluated "green" pretreat chemicals including citric acid and citric acid amended with benzoic acid. We used a mock urine/air separator modeled after the urine collection assembly on ISS. The urine/air separator was challenged continually for >6 months. Depending on the test point, the separator was challenged daily with donated urine and flushed with amended or un-amended reactor effluent. We monitored the pH of the urine, flush solution and residual pH in the urine/air separator after each urine event. We also evaluated solids production and biological growth. Our results support the use of both un-amended and amended bioreactor effluent to maintain the operability of the urine /air separator. The ability to use bioreactor effluent could decrease consumable cost, reduce hazards associated with current pre-treat chemicals, allow other membrane based desalination processes to be utilized, and improve brine characteristics.

  12. The magnetoviscous effect of micellar solutions doped with water based ferrofluids

    Energy Technology Data Exchange (ETDEWEB)

    Arantes, Fabiana R., E-mail: farantes@if.usp.br [Institute of Physics, University of Sao Paulo (Brazil); Institute of Fluid Mechanics, Technische Universität Dresden (Germany); Odenbach, Stefan, E-mail: stefan.odenbach@tu-dresden.de [Institute of Fluid Mechanics, Technische Universität Dresden (Germany)

    2015-09-15

    This work presents a magnetorheological study of micellar solutions of potassium laurate and water doped with magnetite nanoparticles, accompanied by auxiliary dynamic light scattering measurements. An increase in the viscosity of the samples under applied field was observed and, furthermore, a considerable magnetoviscous effect was revealed even at magnetic particles' concentrations as low as 0.005–0.01 vol%. This indicates that the rheological behavior of the micelles is changed by the interaction of the magnetic particles with the applied field, leading to different microscopic arrangements in the micellar solutions. - Highlights: • We study the magnetorheological behavior of micellar solutions doped with ferrofluids. • We observe an increase in the viscosity of the samples under an applied field. • We find a large magnetoviscous effect even at low magnetic particles' concentration. • Interaction of particles with the field changes the micelles' rheological behavior.

  13. Analysis of the Sodium Recirculation Theory of Solute Coupled Water Transport in Small Intestine

    DEFF Research Database (Denmark)

    Larsen, E. H.; Sørensen, Jens Nørkær; Sørensen, J. B.

    2002-01-01

    Our previous mathematical model of solute-coupled water transport through the intestinal epithelium is extended for dealing with electrolytes rather than electroneutral solutes. A 3Na+-2K+ pump in the lateral membranes provides the energy-requiring step for driving transjunctional and translateral......, computations predict that the concentration differences between lis and bathing solutions are small for all three ions. Nevertheless, the diffusion fluxes of the ions out of lis significantly exceed their mass transports. It is concluded that isotonic transport requires recirculation of all three ions....... The computed sodium recirculation flux that is required for isotonic transport corresponds to that estimated in experiments on toad small intestine. This result is shown to be robust and independent of whether the apical entrance mechanism for the sodium ion is a channel, a SGLT1 transporter driving inward...

  14. Iterative solution to the optimal poison management problem in pressurized water reactors

    International Nuclear Information System (INIS)

    Colletti, J.P.; Levine, S.H.; Lewis, J.B.

    1983-01-01

    A new method for solving the optimal poison management problem for a multiregion pressurized water reactor has been developed. The optimization objective is to maximize the end-of-cycle core excess reactivity for any given beginning-of-cycle fuel loading. The problem is treated as an optimal control problem with the region burnup and control absorber concentrations acting as the state and control variables, respectively. Constraints are placed on the power peaking, soluble boron concentration, and control absorber concentrations. The solution method consists of successive relinearizations of the system equations resulting in a sequence of nonlinear programming problems whose solutions converge to the desired optimal control solution. Application of the method to several test problems based on a simplified three-region reactor suggests a bang-bang optimal control strategy with the peak power location switching between the inner and outer regions of the core and the critical soluble boron concentration as low as possible throughout the cycle

  15. Study of influence of various factors on electrochemical signal of lead in water solutions

    Science.gov (United States)

    Zhikharev, Yu N.; Andrianova, L. I.; Ogudova, E. V.

    2018-05-01

    The conditions for obtaining a reproducible signal of lead in water solutions of indifferent electrolytes on various substrates (working electrodes) for analytical purposes were studied. Attention was also paid to studying the regularities of the initial stage of formation of lead sediments by the method of inversion voltammetry. The possibility of using different working electrodes to obtain stable current-potential curves is shown depending on the conditions of electrolysis, pH of the medium, the electrolysis potential and impurities.

  16. Comparative study of structural properties of trehalose water solutions by neutron diffraction, synchrotron radiation and simulation

    Energy Technology Data Exchange (ETDEWEB)

    Cesaro, A.; Magazu, V.; Migliardo, F.; Sussich, F.; Vadala, M

    2004-07-15

    Neutron diffraction measurements combined with H/D substitution have been performed on trehalose aqueous solutions as a function of temperature and concentration by using the SANDALS diffractometer at ISIS Facility (UK). The findings point out a high capability of trehalose to strongly affect the tetrahedral hydrogen bond network of water. The neutron diffraction results are also compared with simulation and experimental data obtained by synchrotron radiation on the phospholipid bilayer membranes (DPPC)/trehalose/H{sub 2}O ternary system.

  17. Influence of pressure on acoustic and rheologic parameters in water solutions of laury sodium sulfate

    Science.gov (United States)

    Khamidov, B. T.; Lezhnev, N. B.

    1995-10-01

    Ultrasonic velocity and density in water solutions of lauril sodium sulphate at frequency 36 MHz, within the range of pressures from 0.1 to 105 MPa at temperature T equals 293 K were measured. According to data of ultrasonic velocity and density under high pressures there was calculated adiabatic compressibility in objects studied from pressure. It was found out that the region of critical concentration of micelle formation has been shifted to the zone of much more low concentrations.

  18. Crystallization of DNA fragments from water-salt solutions, containing 2-methylpentane-2,3-diol.

    Science.gov (United States)

    Osica, V D; Sukharevsky, B Y; Vasilchenko, V N; Verkin, B I; Polyvtsev, O F

    1976-09-01

    Fragments of calf thymus DNA have been crystallized by precipitation from water-salt solutions, containing 2-methylpentane-2,3-diol (MPD). DNA crystals usually take the form either of spherulites up to 100 mu in diameter or of needles with the length up to 50 mu. No irreversible denaturation of DNA occurs during the crystallization process. X-ray diffraction from dense slurries of DNA crystals yields crystalline powder patterns.

  19. Flow friction and heat transfer of ethanol–water solutions through silicon microchannels

    International Nuclear Information System (INIS)

    Wu Huiying; Wu Xinyu; Wei Zhen

    2009-01-01

    An experimental investigation was performed on the flow friction and convective heat transfer characteristics of the ethanol–water solutions flowing through five sets of trapezoidal silicon microchannels having hydraulic diameters ranging from 141.7 µm to 268.6 µm. Four kinds of ethanol–water solutions with the ethanol volume concentrations ranging from 0 to 0.8 were tested under different flow and heating conditions. It was found that the cross-sectional geometric parameters had great effect on the flow friction and heat transfer, and the microchannels with a larger W b /W t (bottom width-to-top width ratio) and a smaller H/W t (depth-to-top width ratio) usually had a larger friction constant and a higher Nusselt number. Entrance effects were significant for the flow friction and heat transfer in silicon microchannels, and decreased with the increase of dimensionless hydrodynamic length L and dimensionless thermal length L + h . When L > 1.0, the hydrodynamic entrance effect on the flow friction was ignorable. For the developed laminar flow in silicon microchannels, the Navier–Stokes equation was applicable. It was also found that the volume concentrations had different effects on the flow friction and heat transfer. Within the experimental range, the effect of volume concentrations on the flow friction was ignorable, and the friction constants of the ethanol–water solutions having different concentrations were the same as those of the pure water. However, volume concentrations had great effect on the convection heat transfer in silicon microchannels. With the increase of the volume concentrations, the Nusselt number of the ethanol–water solutions increased obviously, which was attributed to the combination effect of the increase in the Prantdtl number as well as the volatilization effect of the ethanol. Based on the experimental data, the dimensionless correlations for the flow friction and heat transfer of the ethanol–water solutions in the silicon

  20. Electron spectra and mechanism of complexing of uranyl nitrate in water-acetone solutions

    International Nuclear Information System (INIS)

    Zazhogin, A.A.; Zazhogin, A.P.; Komyak, A.I.; Serafimovich, A.I.

    2003-01-01

    Based on the analysis of the luminescence and electronic absorption spectra, the processes of complexing in an aqueous solution of UO 2 (NO 3 ) 2 ·6H 2 O with small additions of acetone have been studied. In a pure aqueous solution, uranyl exists as the complex UO 2 ·5H 2 O. It is shown that the addition of acetone to the solution leads to the displacement of some water molecules out of the first coordination sphere of uranyl and the formation of the uranyl nitrate dihydrate complexes UO 2 (NO 3 ) 2 ·2H 2 O. It has been established that the stability of these complexes is determined by the decrease in the water activity and in the degree of hydration of uranyl and nitrate, which is the result of the local increase in the concentration of acetone molecules (due to their hydrophobicity) in the regions of the solution where uranyl and nitrate ions are found. The experimental facts supported the mechanism proposed are presented. (authors)

  1. Vapor-liquid equilibria for nitric acid-water and plutonium nitrate-nitric acid-water solutions

    International Nuclear Information System (INIS)

    Maimoni, A.

    1980-01-01

    The liquid-vapor equilibrium data for nitric acid and nitric acid-plutnonium nitrate-water solutions were examined to develop correlations covering the range of conditions encountered in nuclear fuel reprocessing. The scanty available data for plutonium nitrate solutions are of poor quality but allow an order of magnitude estimate to be made. A formal thermodynamic analysis was attempted initially but was not successful due to the poor quality of the data as well as the complex chemical equilibria involved in the nitric acid and in the plutonium nitrate solutions. Thus, while there was no difficulty in correlating activity coefficients for nitric acid solutions over relatively narrow temperature ranges, attempts to extend the correlations over the range 25 0 C to the boiling point were not successful. The available data were then analyzed using empirical correlations from which normal boiling points and relative volatilities can be obtained over the concentration ranges 0 to 700 g/l Pu, 0 to 13 M nitric acid. Activity coefficients are required, however, if estimates of individual component vapor pressures are needed. The required ternary activity coefficients can be approximated from the correlations

  2. The Best Efficiency Point of the Performance of Solar Cell Panel System for Pumping Water at Various Lifting Heads Using 100 W Motor Pump Unit

    OpenAIRE

    Himran, Sukri

    2013-01-01

    This study was carried out experimentally and analytically about the performance of solar cell panel system for operating the pump coupled by dc motor. The solar cell panel with total area 1.9848 m2 consists of three modules of 80 Wp each. The small centrifugal pump powered by dc motor is operated to lift water from 1m to 7m heads in sequence and gives the amount of water pumped over the whole day from 08.00 to 16.00 h are 11988, 10851, 8874, 7695, 5760, 3600...

  3. The Best Efficiency Point of the Performance of Solar Cell Panel System for Pumping Water at Various Lifting Heads Using 100 W Motor- Pump Unit

    OpenAIRE

    S. Himran; B. Mire; N. Salam; L. Sule

    2013-01-01

    This study was carried out experimentally and analytically about the performance of solar cell panel system for operating the pump coupled by dc-motor. The solar cell panel with total area 1.9848 m2 consists of three modules of 80 Wp each. The small centrifugal pump powered by dc-motor is operated to lift water from 1m to 7m heads in sequence and gives the amount of water pumped over the whole day from 08.00 to 16.00 h are 11988, 10851, 8874, 7695, 5760, 3600, 2340 L/d respectively. The hourl...

  4. Replica exchange with solute tempering: A method for sampling biological systems in explicit water

    Science.gov (United States)

    Liu, Pu; Kim, Byungchan; Friesner, Richard A.; Berne, B. J.

    2005-09-01

    An innovative replica exchange (parallel tempering) method called replica exchange with solute tempering (REST) for the efficient sampling of aqueous protein solutions is presented here. The method bypasses the poor scaling with system size of standard replica exchange and thus reduces the number of replicas (parallel processes) that must be used. This reduction is accomplished by deforming the Hamiltonian function for each replica in such a way that the acceptance probability for the exchange of replica configurations does not depend on the number of explicit water molecules in the system. For proof of concept, REST is compared with standard replica exchange for an alanine dipeptide molecule in water. The comparisons confirm that REST greatly reduces the number of CPUs required by regular replica exchange and increases the sampling efficiency. This method reduces the CPU time required for calculating thermodynamic averages and for the ab initio folding of proteins in explicit water. Author contributions: B.J.B. designed research; P.L. and B.K. performed research; P.L. and B.K. analyzed data; and P.L., B.K., R.A.F., and B.J.B. wrote the paper.Abbreviations: REST, replica exchange with solute tempering; REM, replica exchange method; MD, molecular dynamics.*P.L. and B.K. contributed equally to this work.

  5. Enthalpy of solution of α- and β-cyclodextrin in water and in some organic solvents

    International Nuclear Information System (INIS)

    Belica, Sylwia; Sadowska, Monika; Stępniak, Artur; Graca, Anna; Pałecz, Bartłomiej

    2014-01-01

    Highlights: • A great influence of crystalline water on the energetic of dissolving compounds. • The strongest interaction between β-cyclodextrin and DMSO. • The enthalpic pair interaction coefficient, h βCD-EtOH , obtained is positive. • Predominating effects of the partial dehydration of the molecules – βCD-EtOH. -- Abstract: The calorimetric measurements of solution enthalpy of α-cyclodextrin, β-cyclodextrin in water (H 2 O), dimetyloformamid (DMF), dimethyl sulfoxide (DMSO) and aqueous ethanol solutions (H 2 O + EtOH) at 298.15 K were made. The experimental results were used to calculate the enthalpic coefficients of the interactions between cyclodextrin and ethanol molecules in water based on McMillan–Mayer’s model. The results were compared with literature data and with hydrodynamic radii of cyclodextrin in examined solvents and with donor numbers of these solvents. In order to check, if the inclusion complex formation between the solvent with the highest enthalpy of solution and cyclodextrin has happened, the calorimetric isothermal titration measurements were made and the results were interpreted

  6. Behavior of supercooled aqueous solutions stemming from hidden liquid–liquid transition in water

    Energy Technology Data Exchange (ETDEWEB)

    Biddle, John W.; Holten, Vincent; Anisimov, Mikhail A., E-mail: anisimov@umd.edu [Institute for Physical Science and Technology and Department of Chemical and Biomolecular Engineering, University of Maryland, College Park, Maryland 20742 (United States)

    2014-08-21

    A popular hypothesis that explains the anomalies of supercooled water is the existence of a metastable liquid–liquid transition hidden below the line of homogeneous nucleation. If this transition exists and if it is terminated by a critical point, the addition of a solute should generate a line of liquid–liquid critical points emanating from the critical point of pure metastable water. We have analyzed thermodynamic consequences of this scenario. In particular, we consider the behavior of two systems, H{sub 2}O-NaCl and H{sub 2}O-glycerol. We find the behavior of the heat capacity in supercooled aqueous solutions of NaCl, as reported by Archer and Carter [J. Phys. Chem. B 104, 8563 (2000)], to be consistent with the presence of the metastable liquid–liquid transition. We elucidate the non-conserved nature of the order parameter (extent of “reaction” between two alternative structures of water) and the consequences of its coupling with conserved properties (density and concentration). We also show how the shape of the critical line in a solution controls the difference in concentration of the coexisting liquid phases.

  7. Behavior of supercooled aqueous solutions stemming from hidden liquid–liquid transition in water

    International Nuclear Information System (INIS)

    Biddle, John W.; Holten, Vincent; Anisimov, Mikhail A.

    2014-01-01

    A popular hypothesis that explains the anomalies of supercooled water is the existence of a metastable liquid–liquid transition hidden below the line of homogeneous nucleation. If this transition exists and if it is terminated by a critical point, the addition of a solute should generate a line of liquid–liquid critical points emanating from the critical point of pure metastable water. We have analyzed thermodynamic consequences of this scenario. In particular, we consider the behavior of two systems, H 2 O-NaCl and H 2 O-glycerol. We find the behavior of the heat capacity in supercooled aqueous solutions of NaCl, as reported by Archer and Carter [J. Phys. Chem. B 104, 8563 (2000)], to be consistent with the presence of the metastable liquid–liquid transition. We elucidate the non-conserved nature of the order parameter (extent of “reaction” between two alternative structures of water) and the consequences of its coupling with conserved properties (density and concentration). We also show how the shape of the critical line in a solution controls the difference in concentration of the coexisting liquid phases

  8. Behavior of supercooled aqueous solutions stemming from hidden liquid-liquid transition in water.

    Science.gov (United States)

    Biddle, John W; Holten, Vincent; Anisimov, Mikhail A

    2014-08-21

    A popular hypothesis that explains the anomalies of supercooled water is the existence of a metastable liquid-liquid transition hidden below the line of homogeneous nucleation. If this transition exists and if it is terminated by a critical point, the addition of a solute should generate a line of liquid-liquid critical points emanating from the critical point of pure metastable water. We have analyzed thermodynamic consequences of this scenario. In particular, we consider the behavior of two systems, H2O-NaCl and H2O-glycerol. We find the behavior of the heat capacity in supercooled aqueous solutions of NaCl, as reported by Archer and Carter [J. Phys. Chem. B 104, 8563 (2000)], to be consistent with the presence of the metastable liquid-liquid transition. We elucidate the non-conserved nature of the order parameter (extent of "reaction" between two alternative structures of water) and the consequences of its coupling with conserved properties (density and concentration). We also show how the shape of the critical line in a solution controls the difference in concentration of the coexisting liquid phases.

  9. Effect of ionizing radiation on solid and water solution Penicillin G

    International Nuclear Information System (INIS)

    Ben Salem, I.; Amine, Kh.M.; Mabrouk, Y.; Saidi, M.; Mezni, M; Boulila, N; Hafez, E

    2015-01-01

    Penicillin G is a conventional antibiotic used for treatment of different kinds of infectious diseases. Due to its huge quantity production and resistance to biodegradability, this molecule has been a serious concern for clinicians and environmentalists. In this study, the effect of ionizing radiation on the penicillin G powder and in water solution was investigated. The Nuclear Magnetic Resonance (NMR) and fourier transform infrared spectroscopy (FTIR) analysis showed that the ionizing radiation at 50 kGy has no effect on the integrity of solid Penicillin G. The anti-microbial assays revealed that the activity of irradiated solid Penicillin G did not reduce and was stable after storage for one month. Ionizing radiation at 50 kGy led to degradation of water solution Penicillin G. The complete disappear of peaks observed in the control sample confirmed the broken of β-lactam ring, the decarboxylation and cleavage of the thiazolidine ring. The product issued from the irradiation of Penicillin G, was completely removed by the bacterium Cupriavidus.metallidurans. Thus, the ionizing irradiation followed by a biological treatment was very effective method for removing of Penicillin G antibiotics residuals from water solution.

  10. Effect of simple solutes on the long range dipolar correlations in liquid water

    Energy Technology Data Exchange (ETDEWEB)

    Baul, Upayan, E-mail: upayanb@imsc.res.in; Anishetty, Ramesh, E-mail: ramesha@imsc.res.in; Vemparala, Satyavani, E-mail: vani@imsc.res.in [The Institute of Mathematical Sciences, C.I.T. Campus, Taramani, Chennai 600113 (India); Kanth, J. Maruthi Pradeep, E-mail: jmpkanth@gmail.com [Vectra LLC, Mount Road, Chennai 600006 (India)

    2016-03-14

    Intermolecular correlations in liquid water at ambient conditions have generally been characterized through short range density fluctuations described through the atomic pair distribution functions. Recent numerical and experimental results have suggested that such a description of order or structure in liquid water is incomplete and there exist considerably longer ranged orientational correlations in water that can be studied through dipolar correlations. In this study, using large scale classical, atomistic molecular dynamics simulations using TIP4P-Ew and TIP3P models of water, we show that salts such as sodium chloride (NaCl), potassium chloride (KCl), caesium chloride (CsCl), and magnesium chloride (MgCl{sub 2}) have a long range effect on the dipolar correlations, which cannot be explained by the notion of structure making and breaking by dissolved ions. Observed effects are explained through orientational stratification of water molecules around ions and their long range coupling to the global hydrogen bond network by virtue of the sum rule for water. The observations for single hydrophilic solutes are contrasted with the same for a single methane (CH{sub 4}) molecule. We observe that even a single small hydrophobe can result in enhancement of long range orientational correlations in liquid water, contrary to the case of dissolved ions, which have been observed to have a reducing effect. The observations from this study are discussed in the context of hydrophobic effect.

  11. Hybrid solution and pump-storage optimization in water supply system efficiency: A case study

    International Nuclear Information System (INIS)

    Vieira, F.; Ramos, H.M.

    2008-01-01

    Environmental targets and saving energy have become ones of the world main concerns over the last years and it will increase and become more important in a near future. The world population growth rate is the major factor contributing for the increase in global pollution and energy and water consumption. In 2005, the world population was approximately 6.5 billion and this number is expected to reach 9 billion by 2050 [United Nations, 2008. (www.un.org), accessed on July]. Water supply systems use energy for pumping water, so new strategies must be developed and implemented in order to reduce this consumption. In addition, if there is excess of hydraulic energy in a water system, some type of water power generation can be implemented. This paper presents an optimization model that determines the best hourly operation for 1 day, according to the electricity tariff, for a pumped storage system with water consumption and inlet discharge. Wind turbines are introduced in the system. The rules obtained as output of the optimization process are subsequently introduced in a hydraulic simulator, in order to verify the system behaviour. A comparison with the normal water supply operating mode is done and the energy cost savings with this hybrid solution are calculated

  12. Groundwater-Surface Water Interactions and Downstream Transport of Water, Heat, and Solutes in a Hydropeaked River

    Science.gov (United States)

    Ferencz, S. B.; Cardenas, M. B.; Neilson, B. T.; Watson, J.

    2017-12-01

    A majority of the world's largest river systems are regulated by dams. In addition to being used for water resources management and flood prevention, many large dams are also used for hydroelectric power generation. In the United States, dams account for 7% of domestic electricity, and hydropower accounts for 16% of worldwide electricity production. To help meet electricity demand during peak usage times, hydropower utilities often increase their releases of water during high demand periods. This practice, termed hydropeaking, can cause large transient flow regimes downstream of hydroelectric dams. These transient flow increases can result in order of magnitude daily fluctuations in discharge, and the released water can have different thermal and chemical properties than ambient river water. As hydropeaking releases travel downstream, the temporary rise in stage and increase in discharge can enhance surface water-groundwater (SW-GW) exchange between the river and its alluvial aquifer. This dam-induced SW-GW exchange, combined with hydrodynamic attenuation and heat exchange processes, result in complex responses downstream. The dam-regulated Lower Colorado River downstream of Austin, TX was used as a natural laboratory to observe SW-GW interactions and downstream transport of water, heat, and solutes under hydropeaking conditions. To characterize SW-GW interactions, well transects were installed in the banks of the river to observe exchanges between the river and alluvial aquifer. The well transects were installed at three different distances from the dam (15km, 35km, and 80km). At each well transect conductivity, temperature, and pressure sensors were deployed in the monitoring wells and in the channel. Additional conductivity and temperature sensors were deployed along the study reach to provide a more detailed record of heat and solute transport during hydropeaking releases. The field data spans over two months of daily dam releases that were punctuated by two

  13. Engaging the creative to better build science into water resource solutions

    Science.gov (United States)

    Klos, P. Z.

    2014-12-01

    Psychological thought suggests that social engagement with an environmental problem requires 1) cognitive understanding of the problem, 2) emotional engagement with the problem, and 3) perceived efficacy that there is something we can do to solve the problem. Within the water sciences, we form problem-focused, cross-disciplinary teams to help address complex water resource problems, but often we only seek teammates from other disciplines within the realms of engineering and the natural/social sciences. Here I argue that this science-centric focus fails to fully solve these water resource problems, and often the science goes unheard because it is heavily cognitive and lacks the ability to effectively engage the audience through crucial social-psychological aspects of emotion and efficacy. To solve this, future cross-disciplinary collaborations that seek to include creative actors from the worlds of art, humanities, and design can begin to provide a much stronger overlap of the cognition, emotion, and efficacy needed to communicate the science, engage the audience, and create the solutions needed to solve or world's most complex water resource problems. Disciplines across the arts, sciences, and engineering all bring unique strengths that, through collaboration, allow for uniquely creative modes of art-science overlap that can engage people through additions of emotion and efficacy that compliment the science and go beyond the traditional cognitive approach. I highlight examples of this art-science overlap in action and argue that water resource collaborations like these will be more likely to have their hydrologic science accepted and applied by those who decide on water resource solutions. For this Pop-up Talk session, I aim to share the details of this proposed framework in the context of my own research and the work of others. I hope to incite discussion regarding the utility and relevance of this framework as a future option for other water resource

  14. A water activity based model of heterogeneous ice nucleation kinetics for freezing of water and aqueous solution droplets.

    Science.gov (United States)

    Knopf, Daniel A; Alpert, Peter A

    2013-01-01

    Immersion freezing of water and aqueous solutions by particles acting as ice nuclei (IN) is a common process of heterogeneous ice nucleation which occurs in many environments, especially in the atmosphere where it results in the glaciation of clouds. Here we experimentally show, using a variety of IN types suspended in various aqueous solutions, that immersion freezing temperatures and kinetics can be described solely by temperature, T, and solution water activity, a(w), which is the ratio of the vapour pressure of the solution and the saturation water vapour pressure under the same conditions and, in equilibrium, equivalent to relative humidity (RH). This allows the freezing point and corresponding heterogeneous ice nucleation rate coefficient, J(het), to be uniquely expressed by T and a(w), a result we term the a(w) based immersion freezing model (ABIFM). This method is independent of the nature of the solute and accounts for several varying parameters, including cooling rate and IN surface area, while providing a holistic description of immersion freezing and allowing prediction of freezing temperatures, J(het), frozen fractions, ice particle production rates and numbers. Our findings are based on experimental freezing data collected for various IN surface areas, A, and cooling rates, r, of droplets variously containing marine biogenic material, two soil humic acids, four mineral dusts, and one organic monolayer acting as IN. For all investigated IN types we demonstrate that droplet freezing temperatures increase as A increases. Similarly, droplet freezing temperatures increase as the cooling rate decreases. The log10(J(het)) values for the various IN types derived exclusively by Tand a(w), provide a complete description of the heterogeneous ice nucleation kinetics. Thus, the ABIFM can be applied over the entire range of T, RH, total particulate surface area, and cloud activation timescales typical of atmospheric conditions. Lastly, we demonstrate that ABIFM can

  15. Hammerhead ribozyme activity and oligonucleotide duplex stability in mixed solutions of water and organic compounds

    Directory of Open Access Journals (Sweden)

    Shu-ichi Nakano

    2014-01-01

    Full Text Available Nucleic acids are useful for biomedical targeting and sensing applications in which the molecular environment is different from that of a dilute aqueous solution. In this study, the influence of various types of mixed solutions of water and water-soluble organic compounds on RNA was investigated by measuring the catalytic activity of the hammerhead ribozyme and the thermodynamic stability of an oligonucleotide duplex. The compounds with a net neutral charge, such as poly(ethylene glycol, small primary alcohols, amide compounds, and aprotic solvent molecules, added at high concentrations changed the ribozyme-catalyzed RNA cleavage rate, with the magnitude of the effect dependent on the NaCl concentration. These compounds also changed the thermodynamic stability of RNA base pairs of an oligonucleotide duplex and its dependence on the NaCl concentration. Specific interactions with RNA molecules and reduced water activity could account for the inhibiting effects on the ribozyme catalysis and destabilizing effects on the duplex stability. The salt concentration dependence data correlated with the dielectric constant, but not with water activity, viscosity, and the size of organic compounds. This observation suggests the significance of the dielectric constant effects on the RNA reactions under molecular crowding conditions created by organic compounds.

  16. Hydrologic and biogeochemical controls of river subsurface solutes under agriculturally enhanced ground water flow

    Science.gov (United States)

    Wildman, R.A.; Domagalski, Joseph L.; Hering, J.G.

    2009-01-01

    The relative influences of hydrologic processes and biogeochemistry on the transport and retention of minor solutes were compared in the riverbed of the lower Merced River (California, USA). The subsurface of this reach receives ground water discharge and surface water infiltration due to an altered hydraulic setting resulting from agricultural irrigation. Filtered ground water samples were collected from 30 drive point locations in March, June, and October 2004. Hydrologic processes, described previously, were verified by observations of bromine concentrations; manganese was used to indicate redox conditions. The separate responses of the minor solutes strontium, barium, uranium, and phosphorus to these influences were examined. Correlation and principal component analyses indicate that hydrologic processes dominate the distribution of trace elements in the ground water. Redox conditions appear to be independent of hydrologic processes and account for most of the remaining data variability. With some variability, major processes are consistent in two sampling transects separated by 100 m. Copyright ?? 2009 by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America. All rights reserved.

  17. Hydrostatic pressure effect on PNIPAM cononsolvency in water-methanol solutions.

    Science.gov (United States)

    Pica, Andrea; Graziano, Giuseppe

    2017-12-01

    When methanol is added to water at room temperature and 1atm, poly (N-isopropylacrylamide), PNIPAM, undergoes a coil-to-globule collapse transition. This intriguing phenomenon is called cononsolvency. Spectroscopic measurements have shown that application of high hydrostatic pressure destroys PNIPAM cononsolvency in water-methanol solutions. We have developed a theoretical approach that identifies the decrease in solvent-excluded volume effect as the driving force of PNIPAM collapse on increasing the temperature. The same approach indicates that cononsolvency, at room temperature and P=1atm, is caused by the inability of PNIPAM to make all the attractive energetic interactions that it could be engaged in, due to competition between water and methanol molecules. The present analysis suggests that high hydrostatic pressure destroys cononsolvency because the coil state becomes more compact, and the quantity measuring PNIPAM-solvent attractions increases in magnitude due to the solution density increase, and the ability of small water molecules to substitute methanol molecules on PNIPAM surface. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. Milles Iles River : study of solutions to address critically low water levels; Riviere des Milles Iles : etude des solutions de soutien des etiages critiques

    Energy Technology Data Exchange (ETDEWEB)

    Cyr, J F; Fontin, M [Centre d' Expertise Hydrique du Quebec, Quebec, PQ (Canada). Service de la Securite des Barrages

    2006-07-01

    Water management for the Mille Iles River, which supplies drinking water to 400,000 people, was discussed with reference to solutions for critically low water flow which was experienced in 2001 and 2002. The river is part of the Lac des Deux Montagnes watershed in the region of Montreal which is characterized as a high population growth area. In the summer of 2001, municipalities served by the Mille Iles River were faced with problems in the supply of drinking water when the river flow reached only 13 cubic metres per second. The minimal values of flow observed for this time of year have rarely been under 20 cubic metres per second since 1970. The quality of water was reduced under such conditions of flow because the dilution of wastewater discharged into the river became so weak that the aging water treatment facilities had to work beyond their capacity. Quebec's Center of Water Expertise (CEHQ) intervened in an emergency measure to ensure water quality. This study investigated the following 3 possible scenarios for a solution to this problem: (1) to increase the Mille Iles River capacity at the Lac des Deux Montagnes outlet, (2) to reduce the flow discharged by the 3 other outlets of Lac des Deux Montagnes, and (3) to increase the inflow to Lac des Deux Montagnes from reservoirs located in the Ottawa River watershed. The first solution was favoured. 2 refs., 1 tab., 8 figs.

  19. Milles Iles River : study of solutions to address critically low water levels; Riviere des Milles Iles : etude des solutions de soutien des etiages critiques

    Energy Technology Data Exchange (ETDEWEB)

    Cyr, J.F.; Fontin, M. [Centre d' Expertise Hydrique du Quebec, Quebec, PQ (Canada). Service de la Securite des Barrages

    2006-07-01

    Water management for the Mille Iles River, which supplies drinking water to 400,000 people, was discussed with reference to solutions for critically low water flow which was experienced in 2001 and 2002. The river is part of the Lac des Deux Montagnes watershed in the region of Montreal which is characterized as a high population growth area. In the summer of 2001, municipalities served by the Mille Iles River were faced with problems in the supply of drinking water when the river flow reached only 13 cubic metres per second. The minimal values of flow observed for this time of year have rarely been under 20 cubic metres per second since 1970. The quality of water was reduced under such conditions of flow because the dilution of wastewater discharged into the river became so weak that the aging water treatment facilities had to work beyond their capacity. Quebec's Center of Water Expertise (CEHQ) intervened in an emergency measure to ensure water quality. This study investigated the following 3 possible scenarios for a solution to this problem: (1) to increase the Mille Iles River capacity at the Lac des Deux Montagnes outlet, (2) to reduce the flow discharged by the 3 other outlets of Lac des Deux Montagnes, and (3) to increase the inflow to Lac des Deux Montagnes from reservoirs located in the Ottawa River watershed. The first solution was favoured. 2 refs., 1 tab., 8 figs.

  20. Markov process of muscle motors

    International Nuclear Information System (INIS)

    Kondratiev, Yu; Pechersky, E; Pirogov, S

    2008-01-01

    We study a Markov random process describing muscle molecular motor behaviour. Every motor is either bound up with a thin filament or unbound. In the bound state the motor creates a force proportional to its displacement from the neutral position. In both states the motor spends an exponential time depending on the state. The thin filament moves at a velocity proportional to the average of all displacements of all motors. We assume that the time which a motor stays in the bound state does not depend on its displacement. Then one can find an exact solution of a nonlinear equation appearing in the limit of an infinite number of motors

  1. Stainless steels in boiling water reactors. Corrosion problems and possible solutions

    International Nuclear Information System (INIS)

    Combrade, P.; Desestret, A.; Leroy, F.; Coriou, H.

    1977-01-01

    In boiling water reactors, the heat-carrying water may have an up to 0.1 or even 0.2 ppm oxygen content, which can make it highly agressive at operating temperature for stainless steels subject to high physical stresses. Several metallurgical solutions can be considered, and in particular the use of stainless steels having a mixed austenitic-ferritic structure or of standard austenitic steels (18.10 or 18.10 Mo, such as AISI 304 and 316) with carefully controlled carbon and alloy element contents. The behavior of these steels during prolonged tests in water at 288 0 C with a 30 and even 100 ppm oxygen content turned out to be quite satisfactory [fr

  2. Corrosion of dissimilar metal crevices in simulated concentrated ground water solutions at elevated temperature

    Energy Technology Data Exchange (ETDEWEB)

    Ikeda, B.M.; Quinn, M.J

    2003-01-01

    The disposal of high-level nuclear waste in the Yucca Mountain, Nevada is under consideration by the US Department of Energy. The proposed facility will be located in the unsaturated zone approximately 300 m below the surface and 300 m above the water table. The proposed waste container consists of an outer corrosion-resistant Alloy 22 shell surrounding a 316 NG stainless steel structural inner container that encapsulates the used nuclear fuel waste. A titanium drip shield is proposed to protect the waste container from ground water seepage arid rock-fail. A cycle of dripping/evaporation could result in the generation of concentrated aggressive solutions, which could contact the waste container. The waste container material could be susceptible to crevice corrosion from such solutions. The experiments described in this report support the modeling of waste package degradation processes. The intent was to provide parameter values that are required to model crevice corrosion chemistry, as it relates to hydrogen pick-up, and stress corrosion cracking for selected candidate waste package materials. The purpose of the experiments was to study the crevice corrosion behavior of various candidate materials under near freely corroding conditions and to determine the pH developed in crevice solutions. Experimental results of crevice corrosion of dissimilar metal pairs (Alloy 22, Grade-7 and -16 titanium and 316 stainless steel) immersed in a simulated concentrated ground water at {approx}90{sup o}C are reported. The corrosion potential was measured during exposure periods of between 330 and 630 h. Following the experiments, the pH of the crevice solution was measured. The results indicate that a limited degree of crevice acidification occurred during the experiment. The values for corrosion potential suggest that crevice corrosion may have initiated. The total corrosion was limited, with little visible evidence for crevice corrosion being observed on the sample coupon faces

  3. Corrosion of dissimilar metal crevices in simulated concentrated ground water solutions at elevated temperature

    International Nuclear Information System (INIS)

    Ikeda, B.M.; Quinn, M.J.

    2003-01-01

    The disposal of high-level nuclear waste in the Yucca Mountain, Nevada is under consideration by the US Department of Energy. The proposed facility will be located in the unsaturated zone approximately 300 m below the surface and 300 m above the water table. The proposed waste container consists of an outer corrosion-resistant Alloy 22 shell surrounding a 316 NG stainless steel structural inner container that encapsulates the used nuclear fuel waste. A titanium drip shield is proposed to protect the waste container from ground water seepage arid rock-fail. A cycle of dripping/evaporation could result in the generation of concentrated aggressive solutions, which could contact the waste container. The waste container material could be susceptible to crevice corrosion from such solutions. The experiments described in this report support the modeling of waste package degradation processes. The intent was to provide parameter values that are required to model crevice corrosion chemistry, as it relates to hydrogen pick-up, and stress corrosion cracking for selected candidate waste package materials. The purpose of the experiments was to study the crevice corrosion behavior of various candidate materials under near freely corroding conditions and to determine the pH developed in crevice solutions. Experimental results of crevice corrosion of dissimilar metal pairs (Alloy 22, Grade-7 and -16 titanium and 316 stainless steel) immersed in a simulated concentrated ground water at ∼90 o C are reported. The corrosion potential was measured during exposure periods of between 330 and 630 h. Following the experiments, the pH of the crevice solution was measured. The results indicate that a limited degree of crevice acidification occurred during the experiment. The values for corrosion potential suggest that crevice corrosion may have initiated. The total corrosion was limited, with little visible evidence for crevice corrosion being observed on the sample coupon faces. The

  4. Vadose Zone Monitoring of Dairy Green Water Lagoons using Soil Solution Samplers.

    Energy Technology Data Exchange (ETDEWEB)

    Brainard, James R.; Coplen, Amy K

    2005-11-01

    Over the last decade, dairy farms in New Mexico have become an important component to the economy of many rural ranching and farming communities. Dairy operations are water intensive and use groundwater that otherwise would be used for irrigation purposes. Most dairies reuse their process/green water three times and utilize lined lagoons for temporary storage of green water. Leakage of water from lagoons can pose a risk to groundwater quality. Groundwater resource protection infrastructures at dairies are regulated by the New Mexico Environment Department which currently relies on monitoring wells installed in the saturated zone for detecting leakage of waste water lagoon liners. Here we present a proposal to monitor the unsaturated zone beneath the lagoons with soil water solution samplers to provide early detection of leaking liners. Early detection of leaking liners along with rapid repair can minimize contamination of aquifers and reduce dairy liability for aquifer remediation. Additionally, acceptance of vadose zone monitoring as a NMED requirement over saturated zone monitoring would very likely significantly reduce dairy startup and expansion costs. Acknowledgment Funding for this project was provided by the Sandia National Laboratories Small Business Assistance Program

  5. Optimal Water-Power Flow Problem: Formulation and Distributed Optimal Solution

    Energy Technology Data Exchange (ETDEWEB)

    Dall-Anese, Emiliano [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Zhao, Changhong [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Zamzam, Admed S. [University of Minnesota; Sidiropoulos, Nicholas D. [University of Minnesota; Taylor, Josh A. [University of Toronto

    2018-01-12

    This paper formalizes an optimal water-power flow (OWPF) problem to optimize the use of controllable assets across power and water systems while accounting for the couplings between the two infrastructures. Tanks and pumps are optimally managed to satisfy water demand while improving power grid operations; {for the power network, an AC optimal power flow formulation is augmented to accommodate the controllability of water pumps.} Unfortunately, the physics governing the operation of the two infrastructures and coupling constraints lead to a nonconvex (and, in fact, NP-hard) problem; however, after reformulating OWPF as a nonconvex, quadratically-constrained quadratic problem, a feasible point pursuit-successive convex approximation approach is used to identify feasible and optimal solutions. In addition, a distributed solver based on the alternating direction method of multipliers enables water and power operators to pursue individual objectives while respecting the couplings between the two networks. The merits of the proposed approach are demonstrated for the case of a distribution feeder coupled with a municipal water distribution network.

  6. Migration through soil of organic solutes in an oil-shale process water

    Science.gov (United States)

    Leenheer, J.A.; Stuber, H.A.

    1981-01-01

    The migration through soil of organic solutes in an oil-shale process water (retort water) was studied by using soil columns and analyzing leachates for various organic constituents. Retort water extracted significant quantities of organic anions leached from ammonium-saturated-soil organic matter, and a distilled-water rinse, which followed retort-water leaching, released additional organic acids from the soil. After being corrected for organic constitutents extracted from soil by retort water, dissolved-organic-carbon fractionation analyses of effluent fractions showed that the order of increasing affinity of six organic compound classes for the soil was as follows: hydrophilic neutrals nearly equal to hydrophilic acids, followed by the sequence of hydrophobic acids, hydrophilic bases, hydrophobic bases, and hydrophobic neutrals. Liquid-chromatographic analysis of the aromatic amines in the hydrophobic- and hydrophilic-base fractions showed that the relative order of the rates of migration through the soil column was the same as the order of migration on a reversed-phase, octadecylsilica liquid-chromatographic column.

  7. Towards integrated solutions for water, energy, and land using an integrated nexus modeling framework

    Science.gov (United States)

    Wada, Y.

    2017-12-01

    Humanity has already reached or even exceeded the Earth's carrying capacity. Growing needs for food, energy and water will only exacerbate existing challenges over the next decades. Consequently, the acceptance of "business as usual" is eroding and we are being challenged to adopt new, more integrated, and more inclusive development pathways that avoid dangerous interference with the local environment and global planetary boundaries. This challenge is embodied in the United Nation's Sustainable Development Goals (SDGs), which endeavor to set a global agenda for moving towards more sustainable development strategies. To improve and sustain human welfare, it is critical that access to modern, reliable, and affordable water, energy, and food is expanded and maintained. The Integrated Solutions for Water, Energy, and Land (IS-WEL) project has been launched by IIASA, together with the Global Environment Facility (GEF) and the United Nations Industrial Development Organization (UNIDO). This project focuses on the water-energy-land nexus in the context of other major global challenges such as urbanization, environmental degradation, and equitable and sustainable futures. It develops a consistent framework for looking at the water-energy-land nexus and identify strategies for achieving the needed transformational outcomes through an advanced assessment framework. A multi-scalar approach are being developed that aims to combine global and regional integrated assessment tools with local stakeholder knowledge in order to identify robust solutions to energy, water, food, and ecosystem security in selected regions of the world. These are regions facing multiple energy, water and land use challenges and rapid demographic and economic changes, and are hardest hit by increasing climate variability and change. This project combines the global integrated assessment model (MESSAGE) with the global land (GLOBIOM) and water (Community Water Model) model respectively, and the integrated

  8. Assessment of solute fluxes beneath an orchard irrigated with treated sewage water: A numerical study

    Science.gov (United States)

    Russo, David; Laufer, Asher; Shapira, Roi H.; Kurtzman, Daniel

    2013-02-01

    Detailed numerical simulations were used to analyze water flow and transport of nitrate, chloride, and a tracer solute in a 3-D, spatially heterogeneous, variably saturated soil, originating from a citrus orchard irrigated with treated sewage water (TSW) considering realistic features of the soil-water-plant-atmosphere system. Results of this study suggest that under long-term irrigation with TSW, because of nitrate uptake by the tree roots and nitrogen transformations, the vadose zone may provide more capacity for the attenuation of the nitrate load in the groundwater than for the chloride load in the groundwater. Results of the 3-D simulations were used to assess their counterparts based on a simplified, deterministic, 1-D vertical simulation and on limited soil monitoring. Results of the analyses suggest that the information that may be gained from a single sampling point (located close to the area active in water uptake by the tree roots) or from the results of the 1-D simulation is insufficient for a quantitative description of the response of the complicated, 3-D flow system. Both might considerably underestimate the movement and spreading of a pulse of a tracer solute and also the groundwater contamination hazard posed by nitrate and particularly by chloride moving through the vadose zone. This stems mainly from the rain that drove water through the flow system away from the rooted area and could not be represented by the 1-D model or by the single sampling point. It was shown, however, that an additional sampling point, located outside the area active in water uptake, may substantially improve the quantitative description of the response of the complicated, 3-D flow system.

  9. Mathematical model formulation and validation of water and solute transport in whole hamster pancreatic islets.

    Science.gov (United States)

    Benson, James D; Benson, Charles T; Critser, John K

    2014-08-01

    Optimization of cryopreservation protocols for cells and tissues requires accurate models of heat and mass transport. Model selection often depends on the configuration of the tissue. Here, a mathematical and conceptual model of water and solute transport for whole hamster pancreatic islets has been developed and experimentally validated incorporating fundamental biophysical data from previous studies on individual hamster islet cells while retaining whole-islet structural information. It describes coupled transport of water and solutes through the islet by three methods: intracellularly, intercellularly, and in combination. In particular we use domain decomposition techniques to couple a transmembrane flux model with an interstitial mass transfer model. The only significant undetermined variable is the cellular surface area which is in contact with the intercellularly transported solutes, Ais. The model was validated and Ais determined using a 3×3 factorial experimental design blocked for experimental day. Whole islet physical experiments were compared with model predictions at three temperatures, three perfusing solutions, and three islet size groups. A mean of 4.4 islets were compared at each of the 27 experimental conditions and found to correlate with a coefficient of determination of 0.87±0.06 (mean ± SD). Only the treatment variable of perfusing solution was found to be significant (p<0.05). We have devised a model that retains much of the intrinsic geometric configuration of the system, and thus fewer laboratory experiments are needed to determine model parameters and thus to develop new optimized cryopreservation protocols. Additionally, extensions to ovarian follicles and other concentric tissue structures may be made. Copyright © 2014 Elsevier Inc. All rights reserved.

  10. Influence of soil water repellency on runoff and solute loss from New Zealand pasture

    Science.gov (United States)

    Jeyakumar, P.; Müller, K.; Deurer, M.; van den Dijssel, C.; Mason, K.; Green, S.; Clothier, B. E.

    2012-04-01

    Soil water repellency (SWR) has been reported in New Zealand, but knowledge on its importance for the country's economy and environment is limited. Our recent survey on the occurrence of SWR under pasture across the North Island of New Zealand showed that most soils exhibited SWR when dry independent of climate but influenced by the soil order. SWR is discussed as an important soil surface condition enhancing run-off and the transfer of fertilizers and pesticides from agricultural land into waterways. So far, the impact of SWR on run-off has rarely been measured. We developed a laboratory-scale run-off measurement apparatus (ROMA) to quantify directly the impact of SWR on run-off from undisturbed soil slabs. We compared the run-off resulting from the run-on of water with that resulting from an ethanol (30% v/v) solution, which is a fully-wetting liquid even in severely hydrophobic soils. Thus, the experiments with the ethanol solution can be understood as a proxy measure of the wetting-up behaviour of hydrophilic soils. We conducted ROMA run-off experiments with air-dried soil slabs (460 mm long x 190 mm wide x 50 mm deep) collected from pastoral sites, representing three major soil orders in the North Island: Recent Soil (Fluvisol), Gley Soil (Gleysol), and Organic Soil (Histosol), with water followed by the ethanol solution at a run-on rate of 60 mm/h. Bromide was applied at 80 kg KBr/ha prior to the water experiments to assess potential solute losses via run-off. The air-dried soils had a high degree and persistence of SWR (contact angles, 97, 98 and 104° , and potential water drop penetration times, 42, 54 and 231 min for the Fluvisol, Gleysol and Histosol, respectively). Under identical soil and experimental conditions, water generated run-off from all soils, but in the experiments with the ethanol solution, the entire ethanol solution infiltrated into the soils. The ranking of the run-off coefficients of the soils directly reflected their ranking in

  11. 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...

  12. Comparision of Chitosan Function as Adsorbent for Nitrate Removal Using Synthetic Aqueous Solution and Drinking Water

    Directory of Open Access Journals (Sweden)

    Mohammad Norisepehr

    2013-12-01

    Full Text Available Background & Objectives: Nitrate and nitrite compounds pollution of groundwater resources in recent years which recently their mean concentration due to enhancement of different kind of municipal, industrial and agriculture waste water, were increased. The most common source of nitrates entering the water include chemical fertilizers and animal manure in agriculture, septic tank effluent, wastewater, wastewater treatment plants, animal and plant residue analysis on the ground of non-sanitary disposal of solid waste and the use of absorbing wells for sewage disposal. Materials and methods: This experimental study is applied to the nitrate removal using chitosan in laboratory scale at ambient temperature and the design of the system was Batch. Effects of parameters such as pH, contact time, initial concentration and adsorbent concentration of nitrate on nitrate removal from aqueous solution was studied. Results: Function of chitosan in synthetic aqueous solution and drinking water according to the slurry system results, the optimum condition was obtained at pH=4, 20 min contact time and increasing the initial concentration of nitrate enhance the adsorption capacity of chitosan. Also optimum dosage of adsorbent was obtained at 0.5 g/l. The data obtained from the experiments of adsorbent isotherm were analyzed using Langmuir and Freundlich isotherm models. The Langmuir equation was found to be the best fitness with the experimental data (R2>0.93. Conclusion: Although efficiency of Nitrate removal in synthetic aqueous solution was better than drinking water, adsorption process using chitosan as an option for the design and selection nitrate removal should be considered in order to achieve environmental standards.

  13. Modelling transport of water and solutes in future wetlands in Forsmark

    Energy Technology Data Exchange (ETDEWEB)

    Vikstroem, Maria; Gustafsson, Lars-Goeran [DHI Water and Environment AB, Vaexjoe (Sweden)

    2006-03-15

    been analyzed. Results from the transport modelling show that a solute in the bedrock is transported quickly towards the peat surface in discharge areas for Bolundsfjaerden. After around 10 years, a stationary condition is reached. For the recharge area that develops in large parts of the mire, the solute is transported through horizontal dispersion, which results in much lower concentrations. The solute concentration is at the lowest where the overland water pressure is at the highest close to the south western inlet. Puttan has a vertical flow pattern that differs from Bolundsfjaerden. The pressure from water on the peat surface is considerably lower and for a major part of the year Puttan is a discharge area with an upwards flow direction. The spatial distribution of solutes is more even over the surface than for Bolundsfjaerden, but higher concentrations are found around today's shoreline. A solute reaching the wetland through surface runoff is transported relatively slow through the mire at Bolundsfjaerden. Due to the recharge conditions, the solute is spread to the underlying soil layers. The vertical solute transport follows the discharge and recharge areas, where high concentrations, up to the source strength, are reached in major parts of the formation, while lower concentrations are reached in the discharge areas and underneath clay sediment.

  14. Modelling transport of water and solutes in future wetlands in Forsmark

    International Nuclear Information System (INIS)

    Vikstroem, Maria; Gustafsson, Lars-Goeran

    2006-03-01

    analyzed. Results from the transport modelling show that a solute in the bedrock is transported quickly towards the peat surface in discharge areas for Bolundsfjaerden. After around 10 years, a stationary condition is reached. For the recharge area that develops in large parts of the mire, the solute is transported through horizontal dispersion, which results in much lower concentrations. The solute concentration is at the lowest where the overland water pressure is at the highest close to the south western inlet. Puttan has a vertical flow pattern that differs from Bolundsfjaerden. The pressure from water on the peat surface is considerably lower and for a major part of the year Puttan is a discharge area with an upwards flow direction. The spatial distribution of solutes is more even over the surface than for Bolundsfjaerden, but higher concentrations are found around today's shoreline. A solute reaching the wetland through surface runoff is transported relatively slow through the mire at Bolundsfjaerden. Due to the recharge conditions, the solute is spread to the underlying soil layers. The vertical solute transport follows the discharge and recharge areas, where high concentrations, up to the source strength, are reached in major parts of the formation, while lower concentrations are reached in the discharge areas and underneath clay sediment

  15. The composite water and solute transport of barley (Hordeum vulgare) roots: effect of suberized barriers.

    Science.gov (United States)

    Ranathunge, Kosala; Kim, Yangmin X; Wassmann, Friedrich; Kreszies, Tino; Zeisler, Viktoria; Schreiber, Lukas

    2017-03-01

    Roots have complex anatomical structures, and certain localized cell layers develop suberized apoplastic barriers. The size and tightness of these barriers depend on the growth conditions and on the age of the root. Such complex anatomical structures result in a composite water and solute transport in roots. Development of apoplastic barriers along barley seminal roots was detected using various staining methods, and the suberin amounts in the apical and basal zones were analysed using gas chromatography-mass spectometry (GC-MS). The hydraulic conductivity of roots ( Lp r ) and of cortical cells ( Lp c ) was measured using root and cell pressure probes. When grown in hydroponics, barley roots did not form an exodermis, even at their basal zones. However, they developed an endodermis. Endodermal Casparian bands first appeared as 'dots' as early as at 20 mm from the apex, whereas a patchy suberin lamellae appeared at 60 mm. The endodermal suberin accounted for the total suberin of the roots. The absolute amount in the basal zone was significantly higher than in the apical zone, which was inversely proportional to the Lp r . Comparison of Lp r and Lp c suggested that cell to cell pathways dominate for water transport in roots. However, the calculation of Lp r from Lp c showed that at least 26 % of water transport occurs through the apoplast. Roots had different solute permeabilities ( P sr ) and reflection coefficients ( σ sr ) for the solutes used. The σ sr was below unity for the solutes, which have virtually zero permeability for semi-permeable membranes. Suberized endodermis significantly reduces Lp r of seminal roots. The water and solute transport across barley roots is composite in nature and they do not behave like ideal osmometers. The composite transport model should be extended by adding components arranged in series (cortex, endodermis) in addition to the currently included components arranged in parallel (apoplastic, cell to cell pathways). © The

  16. Total phenol content and antioxidant activity of water solutions of plant extracts

    Directory of Open Access Journals (Sweden)

    Mirela Kopjar

    2009-01-01

    Full Text Available Water solutions of extracts were investigated for total phenol content, flavonoid content and antioxidant activity. Susceptibility to degradation of water solutions of plant extracts, under light and in the dark, during storage at room temperature was investigated in order to determine their stability prior to their application for fortification of food products. Large dispersion of total phenol (TP content in the investigated model solutions of selected extracts (olive leaves, green tea, red grape, red wine, pine bark PE 5:1, pine bark PE 95 %, resveratrol, ranging from 11.10 mg GAE/100 mL to 92.19 mg GAE/100 mL was observed. Consequently, large dispersion of total flavonoids (TF content (8.89 mg to 61.75 mg CTE/100 mL was also observed. Since phenols have been mostly responsible for antioxidant activity of extracts, in most cases, antioxidant activity followed the TP content. That was proven by estimation of correlation coefficient between the total phenol content and antioxidant activity. Correlation coefficients between investigated parameters ranged from 0.5749 to 0.9604. During storage of 5 weeks at room temperature loss of phenols and flavonoids occurred. Antioxidant activity decreased with the decrease of TP and TF content. Degradations of phenols and flavonoids were more pronounced in samples stored at light.

  17. Liquid microjet synchrotron-radiation spectroscopy for biomolecules in water solution 2

    International Nuclear Information System (INIS)

    Shimada, Hiroyuki; Ukai, Masatoshi

    2014-01-01

    A new spectroscopic research of radiation induced damage on DNA and its constituent molecules is proposed, which is made possible using a liquid microjet technique for bio-solution under vacuum in combination with synchrotron-radiation aided site-selective excitation. The latter part of the proposal article describes the present state of research on the selective primary radiation interaction by looking at base moieties of nucleotides. X-ray absorption near edge structure (XANES) spectra at energies around the nitrogen K-edge for nucleotides, adenosine-5'-monophosphate (AMP), guanosine-5'-monophosophate (GMP), cytidine-5'-monophosophate (CMP), and adenosine-5'-triphosphate (ATP) in aqueous solutions are presented. Selective excitation of a base moiety using a synchrotron radiation allows us to investigate the interaction of the base moiety with water solvent. We discuss the change of spectral character of XANES which reveals to the structural change of the base moiety under different pH environmental condition of water solution. Through the present research a scope for cooperative direct and indirect primary radiation effects is given. (author)

  18. Water-Reflected 233U Uranyl Nitrate Solutions in Simple Geometry

    International Nuclear Information System (INIS)

    Elam, K.R.

    2001-01-01

    A number of critical experiments involving 233 U were performed in the Oak Ridge National Laboratory Building 9213 Critical Experiments Facility during the years 1952 and 1953. These experiments, reported in Reference 1, were directed toward determining bounding values for the minimum critical mass, minimum critical volume, and maximum safe pipe size of water-moderated solutions of 233 U. Additional information on the critical experiments was found in the experimental logbooks. Two experiments utilizing uranyl nitrate (UO 2 (NO 3 ) 2 ) solutions in simple geometry are evaluated in this report. Experiment 37 is in a 10.4-inch diameter sphere, and Experiment 39 is in a 10-inch diameter cylinder. The 233 U concentration ranges from 49 to 62 g 233 U/l. Both experiments were reflected by at least 6 inches of water in all directions. Paraffin-reflected uranyl nitrate experiments, also reported in Reference 1, are evaluated elsewhere. Experiments with smaller paraffin reflected 5-, 6-, and 7.5-inch diameter cylinders are evaluated in U233-SOL-THERM-004. Experiments with paraffin reflected 8-, 8.5-, 9-, 10-, and 12-inch diameter cylinders are evaluated in U233-SOL-THERM-002. Later experiments with highly-enriched 235 U uranyl fluoride solution in the same 10.4-inch diameter sphere are reported in HEU-SOL-THERM-010. Both experiments were judged acceptable for use as criticality-safety benchmark experiments

  19. Evaporation of a sessile water drop and a drop of aqueous salt solution.

    Science.gov (United States)

    Misyura, S Y

    2017-11-07

    The influence of various factors on the evaporation of drops of water and aqueous salt solution has been experimentally studied. Typically, in the studies of drop evaporation, only the diffusive vapor transfer, radiation and the molecular heat conduction are taken into account. However, vapor-gas convection plays an important role at droplet evaporation. In the absence of droplet boiling, the influence of gas convection turns out to be the prevailing factor. At nucleate boiling, a prevailing role is played by bubbles generation and vapor jet discharge at a bubble collapse. The gas convection behavior for water and aqueous salt solution is substantially different. With a growth of salt concentration over time, the influence of the convective component first increases, reaches an extremum and then significantly decreases. At nucleate boiling in a salt solution it is incorrect to simulate the droplet evaporation and the heat transfer in quasi-stationary approximation. The evaporation at nucleate boiling in a liquid drop is divided into several characteristic time intervals. Each of these intervals is characterized by a noticeable change in both the evaporation rate and the convection role.

  20. Two-dimensional finite element solution for the simultaneous transport of water and solutes through a nonhomogeneous aquifer under transient saturated unsaturated flow conditions

    International Nuclear Information System (INIS)

    Gureghian, A.B.

    1979-01-01

    A mathematical model of ground water transport through an aquifer is presented. The solute of interest is a metal tracer or radioactive material which may undergo decay through a sorbing unconfined aquifer. The subject is developed under the following headings: flow equation, solute equation, boundary conditions, finite element formulation, element formulation, solution scheme (flow equation, solute equation), results and discussions, water movement in a ditch drained aquifer under transient state, water and solute movement in a homogeneous and unsaturated soil, transport of 226 Ra in nonhomogeneous aquifer, tailings pond lined, and tailings pond unlined. It is concluded that this mathematical model may have a wide variety of applications. The uranium milling industry may find it useful to evaluate the hydrogeological suitability of their disposal sites. It may prove suited for the design of clay disposal ponds destined to hold hazardous liquids. It may also provide a means of estimating the long-term impact of radionuclides or other pollutants on the quality of ground water. 31 references, 9 figures, 3 tables

  1. Artificial molecular motors

    NARCIS (Netherlands)

    Kassem, Salma; van Leeuwen, Thomas; Lubbe, Anouk S.; Wilson, Miriam R.; Feringa, Ben L.; Leigh, David A.

    2017-01-01

    Motor proteins are nature's solution for directing movement at the molecular level. The field of artificial molecular motors takes inspiration from these tiny but powerful machines. Although directional motion on the nanoscale performed by synthetic molecular machines is a relatively new

  2. Performance of Potassium Bicarbonate and Calcium Chloride Draw Solutions for Desalination of Saline Water Using Forward Osmosis

    Directory of Open Access Journals (Sweden)

    M. Nematzadeh

    2015-01-01

    Full Text Available Forward osmosis (FO has recently drawn attention as a promising membrane based method for seawater and brackish water desalination. In this study, we focus on the use of calciun chloride (CaCl2 and potassium bicarbonate (KHCO3 as inorganic salt draw solution candidates due to their appropriate performance in water flux and reverse salt diffusion as well as reasonable cost. The experiments were carried at 25 °C and cross-flow rate of 3 L min−1.  At the same osmotic pressure, the water flux of CaCl2 draw solution tested against deionized feed water, showed 20% higher permeation than KHCO3, which it was attributed to the lower internal concentration polarization (ICP. The reverse diffusion of CaCl2 was found higher than KHCO3 solution which it would be related to the smaller ionic size and the higher permeation of this salt through the membrane. The water flux for both draw solutions against 0.33 M NaCl feed solution was about 2.8 times lower than deionized feed water because of ICP. Higher concentrations of draw solution is required for increasing the water permeation from saline water feed towards the draw side.

  3. Effect of pH Upper Control Limit on Nutrient Solution Component and Water Spinach Growth under Hydroponics

    OpenAIRE

    Xuzhang Xue; Yinkun Li; Feng Li; Fang Zhang; Wenzhong Guo

    2015-01-01

    In this study, experiment with four levels of nutrient solution pH control upper limit was conducted to explore the optimal nutrient solution pH management scheme under hydroponics by evaluating the nutrient solution characters i.e., pH, Electric Conductivity (EC), nitrate, soluble phosphorus (soluble-P), water spinach growth and quality. The results showed that the nutrient solution pH was 8.2 and unsuitable for water spinach growth under the treatment with no pH regulation during the experi...

  4. Water and Solute Transport in Arid Vadose Zones: Innovations in Measurement and Analysis

    International Nuclear Information System (INIS)

    Tyler, S W.; Scanlon, Bridget R.; Gee, Glendon W.; Allison, G B.; Parlange, M. B.; Hopmans, J. W.

    1999-01-01

    Understanding the physics of flow and transport through the vadose zone has advanced significantly in the last three decades. These advances have been made primarily in humid regions or in irrigated agricultural settings. While some of the techniques are useful, many are not suited to arid regions. The fluxes of water and solutes typically found in arid regions are often orders of magnitude smaller than those found in agricultural settings, while the time scales for transport can be orders of magnitude larger. The depth over which transport must be characterized is also often much greater than in humid regions. Rather than relying on advances in applied tracers, arid-zone researchers have developed natural tracer techniques that are capable of quantifying transport over tens to thousands of years. Techniques have been developed to measure the hydraulic properties of sediments at all water contents, including the very dry range and at far greater depths. As arid and semiarid regions come under increased development pressures for such activities as hazardous- and radioactive-waste disposal, the development of techniques and the understanding of water and solute transport have become crucial components in defining the environmental impacts of activities at the landsurface

  5. Solution to valve failures at Braidwood induced by service water cavitation

    International Nuclear Information System (INIS)

    Ozol, J.; Schipiour, B.K.; Wix, J.E.

    1994-01-01

    Control valves throttle fluid from a high pressure to a lower pressure. On water systems, this throttling process may be accompanied by cavitation, which induces valve noise, vibration, and material damage. Extensive and significant caviation erosion has been experienced the last 10 years in most service water control valve bodies, downstream flanges, and reducers at Braidwood Station. There have been 40 different and distinct cavitation-induced failures in the service water system at Braidwood Station. These failures have created significant costs and continue to be a lingering source of operational maintenance costs to the Commonwealth Edison Company, which is incurring significant financial losses. It should be noted that almost all service water control valves experience some cavitation effects. Cavitation and cavitation damage are complex and elusive phenomena for which no single, simple analytical model exists. The purpose of this paper is to explain features of service water control valve cavitation failures and some of the solutions used by Commonwealth Edison at their six nuclear stations. The paper discusses the following: (1) Braidwood's history of erosion from cavitation; (2) Erosion-corrosion considerations; (3) The Instrument Society of America's valve sizing equations and how they relate to cavitation; (4) Methods to eliminate cavitation; (5) Corrective actions and practical approaches used by Commonwealth Edison to eliminate cavitation

  6. Water as a solute in aprotic dipolar solvents. 2. D2O-H2O solute isotope effects on the enthalpy of water dissolution in nitromethane, acetonitrile and propylene carbonate at 298.15 K

    International Nuclear Information System (INIS)

    Ivanov, Evgeniy V.; Smirnov, Valeriy I.

    2010-01-01

    The enthalpies of solution of ordinary (H 2 O) and heavy (D 2 O) water in nitromethane (NM), acetonitrile (ACN) and propylene carbonate (PC) were measured calorimetrically at 298.15 K. Standard (at the infinite dilution) enthalpies of solution and solvation, along with D 2 O-H 2 O solute isotope effects on the quantities in question, were calculated. The enthalpies of solution of water H/D isotopologues were found to be positive by sign and substantially increasing in magnitude on going from ACN and PC to NM, whereas the corresponding positive solute H/D isotope effect changes in a consequence: NM > ACN > PC. The qualitative interrelations between the enthalpy-isotopic effect of dissolution (solvation) of water and the electron-accepting/donating ability of aprotic dipolar solvent (within a series considered) were found.

  7. Pin Hole Discharge Creation in Na2SO4 Water Solutions

    Directory of Open Access Journals (Sweden)

    Lucie Hlavatá

    2013-01-01

    Full Text Available This work deals with the diaphragm discharge generated in water solutions containing Na2SO4 as a supporting electrolyte. The solution conductivity was varied in the range of 270 ÷ 750 µScm-1. The batch plasma reactor with volume of 100 ml was divided into two electrode spaces by the Shapal-MTM ceramics dielectric barrier with a pin-hole (diameter of 0.6 mm. Three variable barrier thicknesses (0.3; 0.7 and 1.5 mm and non-pulsed DC voltage up to 2 kV were used for the discharge creation. Each of the current–voltage characteristic can be divided into three parts: electrolysis, bubble formation and discharge operation. The experimental results showed that the discharge ignition moment in the pin-hole was significantly dependent on the dielectric diaphragm thickness. Breakdown voltage increases with the increase of the dielectric barrier thickness.

  8. Sorption and permeation of solutions of chloride salts, water and methanol in a Nafion membrane

    International Nuclear Information System (INIS)

    Villaluenga, J.P.G.; Barragan, V.M.; Seoane, B.; Ruiz-Bauza, C.

    2006-01-01

    The sorption of water-methanol mixtures containing a dissolved chloride salt in a Nafion 117 membrane, and their transport through the membrane under the driving force of a pressure gradient, have been studied. Both type of experiments was performed by using five different salts: lithium chloride, sodium chloride, cesium chloride, magnesium chloride and calcium chloride. It was observed that both the permeation flow through the membrane and the membrane swelling increase significantly with the methanol content of the solutions. These facts are attributed to the increase in wet membrane porosity, which brings about the increase of the mobility of solvents in the membrane, besides the increase of the mobility of the polymer pendant chains. In contrast, the influence of the type of electrolyte on the membrane porosity and permeability is not very important, with the exception of the CsCl solutions, which is probably due to the small hydration ability of the Cs + ion

  9. Irrigation solutions in open fractures of the lower extremities: evaluation of isotonic saline and distilled water.

    Science.gov (United States)

    Olufemi, Olukemi Temiloluwa; Adeyeye, Adeolu Ikechukwu

    2017-01-01

    Open fractures are widely considered as orthopaedic emergencies requiring immediate intervention. The initial management of these injuries usually affects the ultimate outcome because open fractures may be associated with significant morbidity. Wound irrigation forms one of the pivotal principles in the treatment of open fractures. The choice of irrigation fluid has since been a source of debate. This study aimed to evaluate and compare the effects of isotonic saline and distilled water as irrigation solutions in the management of open fractures of the lower extremities. Wound infection and wound healing rates using both solutions were evaluated. This was a prospective hospital-based study of 109 patients who presented to the Accident and Emergency department with open lower limb fractures. Approval was sought and obtained from the Ethics Committee of the Hospital. Patients were randomized into either the isotonic saline (NS) or the distilled water (DW) group using a simple ballot technique. Twelve patients were lost to follow-up, while 97 patients were available until conclusion of the study. There were 50 patients in the isotonic saline group and 47 patients in the distilled water group. Forty-one (42.3%) of the patients were in the young and economically productive strata of the population. There was a male preponderance with a 1.7:1 male-to-female ratio. The wound infection rate was 34% in the distilled water group and 44% in the isotonic saline group (p = 0.315). The mean time ± SD to wound healing was 2.7 ± 1.5 weeks in the distilled water group and 3.1 ± 1.8 weeks in the isotonic saline group (p = 0.389). It was concluded from this study that the use of distilled water compares favourably with isotonic saline as an irrigation solution in open fractures of the lower extremities. © The Authors, published by EDP Sciences, 2017.

  10. Irrigation solutions in open fractures of the lower extremities: evaluation of isotonic saline and distilled water

    Directory of Open Access Journals (Sweden)

    Olufemi Olukemi Temiloluwa

    2017-01-01

    Full Text Available Introduction: Open fractures are widely considered as orthopaedic emergencies requiring immediate intervention. The initial management of these injuries usually affects the ultimate outcome because open fractures may be associated with significant morbidity. Wound irrigation forms one of the pivotal principles in the treatment of open fractures. The choice of irrigation fluid has since been a source of debate. This study aimed to evaluate and compare the effects of isotonic saline and distilled water as irrigation solutions in the management of open fractures of the lower extremities. Wound infection and wound healing rates using both solutions were evaluated. Methods: This was a prospective hospital-based study of 109 patients who presented to the Accident and Emergency department with open lower limb fractures. Approval was sought and obtained from the Ethics Committee of the Hospital. Patients were randomized into either the isotonic saline (NS or the distilled water (DW group using a simple ballot technique. Twelve patients were lost to follow-up, while 97 patients were available until conclusion of the study. There were 50 patients in the isotonic saline group and 47 patients in the distilled water group. Results: Forty-one (42.3% of the patients were in the young and economically productive strata of the population. There was a male preponderance with a 1.7:1 male-to-female ratio. The wound infection rate was 34% in the distilled water group and 44% in the isotonic saline group (p = 0.315. The mean time ± SD to wound healing was 2.7 ± 1.5 weeks in the distilled water group and 3.1 ± 1.8 weeks in the isotonic saline group (p = 0.389. Conclusions: It was concluded from this study that the use of distilled water compares favourably with isotonic saline as an irrigation solution in open fractures of the lower extremities.

  11. Using a hybrid model to predict solute transfer from initially saturated soil into surface runoff with controlled drainage water.

    Science.gov (United States)

    Tong, Juxiu; Hu, Bill X; Yang, Jinzhong; Zhu, Yan

    2016-06-01

    The mixing layer theory is not suitable for predicting solute transfer from initially saturated soil to surface runoff water under controlled drainage conditions. By coupling the mixing layer theory model with the numerical model Hydrus-1D, a hybrid solute transfer model has been proposed to predict soil solute transfer from an initially saturated soil into surface water, under controlled drainage water conditions. The model can also consider the increasing ponding water conditions on soil surface before surface runoff. The data of solute concentration in surface runoff and drainage water from a sand experiment is used as the reference experiment. The parameters for the water flow and solute transfer model and mixing layer depth under controlled drainage water condition are identified. Based on these identified parameters, the model is applied to another initially saturated sand experiment with constant and time-increasing mixing layer depth after surface runoff, under the controlled drainage water condition with lower drainage height at the bottom. The simulation results agree well with the observed data. Study results suggest that the hybrid model can accurately simulate the solute transfer from initially saturated soil into surface runoff under controlled drainage water condition. And it has been found that the prediction with increasing mixing layer depth is better than that with the constant one in the experiment with lower drainage condition. Since lower drainage condition and deeper ponded water depth result in later runoff start time, more solute sources in the mixing layer are needed for the surface water, and larger change rate results in the increasing mixing layer depth.

  12. The phase equilibria of multicomponent gas hydrate in methanol/ethylene glycol solution based formation water

    International Nuclear Information System (INIS)

    Xu, Shurui; Fan, Shuanshi; Yao, Haiyuan; Wang, Yanhong; Lang, Xuemei; Lv, Pingping; Fang, Songtian

    2017-01-01

    Highlights: • The equilibrium data in THI solution based formation water is first investigated. • The 0.55 mass fraction concentration of EG 0.55 mass fraction fills the vacancy of this area. • The testing pressure range from 4.22 MPa to 34.72 MPa was rare in published data. - Abstract: In this paper, the three-phase coexistence points are generated for multicomponent gas hydrate in methanol (MeOH) solution for (0.05, 0.10, 0.15, and 0.35) mass fraction and ethylene glycol (EG) solution for (0.05, 0.10, 0.15, 0.35, 0.40 and 0.55) mass fraction. The phase equilibrium curves of different system were obtained by an isochoric pressure-search method on high pressure apparatus. The phase equilibrium regions of multicomponent gas hydrate were measured using the same composition of natural gas distributed in the South China Sea. And the different concentration solutions were prepared based formation water. The experimental data were measured in a wide range temperature from 267.74 to 298.53 K and a wide range pressure from 4.22 MPa to 34.72 MPa. The results showed that the hydrate phase equilibrium curves shifted to the inhibition region in accordance with the increased inhibitor concentration. In addition, the equilibrium temperature would decrease about 2.7 K when the concentration of MeOH increased 0.05 mass fraction. Besides, the suppression temperature was 1.25 K with the 0.05 mass fraction increase of EG concentration in the range of 0.05 mass fraction to 0.15 mass fraction. While in high EG concentration region, the suppression temperature was 3.3 K with the same increase of EG concentration (0.05 mass fraction).

  13. Solution thermodynamics and preferential solvation of sulfamethazine in (methanol + water) mixtures

    International Nuclear Information System (INIS)

    Delgado, Daniel R.; Almanza, Ovidio A.; Martínez, Fleming; Peña, María A.; Jouyban, Abolghasem; Acree, William E.

    2016-01-01

    Highlights: • Solubility of sulfamethazine (SMT) was measured in (methanol + water) mixtures. • SMT solubility was correlated with Jouyban–Acree model. • Gibbs energy, enthalpy, and entropy of dissolution of SMT were calculated. • Non-linear enthalpy–entropy relationship was observed for SMT. • Preferential solvation of SMT by methanol was analyzed by using the IKBI method. - Abstract: The solubility of sulfamethazine (SMT) in {methanol (1) + water (2)} co-solvent mixtures was determined at five different temperatures from (293.15 to 313.15) K. The sulfonamide exhibited its highest mole fraction solubility in pure methanol (δ 1 = 29.6 MPa 1/2 ) and its lowest mole fraction solubility in water (δ 2 = 47.8 MPa 1/2 ) at each of the five temperatures studied. The Jouyban–Acree model was used to correlate/predict the solubility values. The respective apparent thermodynamic functions Gibbs energy, enthalpy, and entropy of solution were obtained from the solubility data through the van’t Hoff and Gibbs equations. Apparent thermodynamic quantities of mixing were also calculated for this drug using values of the ideal solubility reported in the literature. A non-linear enthalpy–entropy relationship was noted for SMT in plots of both the enthalpy vs. Gibbs energy of mixing and the enthalpy vs. entropy of mixing. These plots suggest two different trends according to the slopes obtained when the composition of the mixtures changes. Accordingly, the mechanism for SMT transfer processes in water-rich mixtures from water to the mixture with 0.70 in mass fraction of methanol is entropy driven. Conversely, the mechanism is enthalpy driven in mixtures whenever the methanol composition exceeds 0.70 mol fraction. An inverse Kirkwood–Buff integral analysis of the preferential solvation of SMT indicated that the drug is preferentially solvated by water in water-rich mixtures but is preferentially solvated by methanol in methanol-rich mixtures.

  14. A Holistic ICT Solution to Improve Matching between Supply and Demand over the Water Supply Distribution Chain

    Directory of Open Access Journals (Sweden)

    Gabriel Anzaldi

    2014-12-01

    Full Text Available While many water management tools exist, these systems are not usually interconnected and therefore cannot communicate between one another, preventing Integrated Water Resources Management to be fully achieved. This paper presents the solution proposed by WatERP project* where a novel solution enables better matching between water supply and demand from holistic perspective. Subsystems that control the production, management and consumption of water will be interconnected through both information architecture and intelligent infrastructure. The main outcome will consist of, a web-based Open Management Platform integrating near real-time knowledge on water supplies and demand, from sources to users, across geographic and organizational scales and supported by a knowledge base where information will be structured in water management ontology to ensure interoperability and maximize usability. WatERP will thus provide a major contribution to: 1 Improve coordination among actors, 2 Foster behavioural change, 3 Reduce water and energy consumption, 4 Optimize water accountability.

  15. Benchmark calculation for water reflected STACY cores containing low enriched uranyl nitrate solution

    International Nuclear Information System (INIS)

    Miyoshi, Yoshinori; Yamamoto, Toshihiro; Nakamura, Takemi

    2001-01-01

    In order to validate the availability of criticality calculation codes and related nuclear data library, a series of fundamental benchmark experiments on low enriched uranyl nitrate solution have been performed with a Static Experiment Criticality Facility, STACY in JAERI. The basic core composed of a single tank with water reflector was used for accumulating the systematic data with well-known experimental uncertainties. This paper presents the outline of the core configurations of STACY, the standard calculation model, and calculation results with a Monte Carlo code and JENDL 3.2 nuclear data library. (author)

  16. Osmotic coefficients of water for thorium nitrate solutions at 25, 37, and 50oC

    International Nuclear Information System (INIS)

    Lemire, R.J.; Sagert, N.H.; Lau, D.W.P.

    1983-01-01

    Vapor pressure osmometry was used to measure osmotic coefficients of water for thorium nitrate solutions at 25, 37, and 50 o C and at molalities up to 0.2 mol·kg -1 . The data were fitted to three- and four-parameter equations containing limiting-law terms for a 4:1 electrolyte. The variation of the osmotic coefficients as a function of temperature was found to be small. The results are compared to published values for the osmotic coefficients. (author)

  17. The main mechanisms of flotation extraction of heavy metal ions out of water solutions

    International Nuclear Information System (INIS)

    Zubareva, G.I.

    2002-01-01

    Flotation extraction of heavy metal ions out of water solutions using reagent EMKO (sodium soaps of vat residues of C grade) is presented. It is established that it is related to hydration energy and stability of sublates being formed. These two parameters affect contrariwise. A difference of molar ratios [EMKO]:[Me] in the course of extracting metals into froth can be explained by their different aggregative state, and a proportion of ionic form of metals and hydroxides being formed. Metal flotation rate is different for each of metal cations to be floated and is dependant on hydrogen ion concentrations [ru

  18. WATSFAR: numerical simulation of soil WATer and Solute fluxes using a FAst and Robust method

    Science.gov (United States)

    Crevoisier, David; Voltz, Marc

    2013-04-01

    To simulate the evolution of hydro- and agro-systems, numerous spatialised models are based on a multi-local approach and improvement of simulation accuracy by data-assimilation techniques are now used in many application field. The latest acquisition techniques provide a large amount of experimental data, which increase the efficiency of parameters estimation and inverse modelling approaches. In turn simulations are often run on large temporal and spatial domains which requires a large number of model runs. Eventually, despite the regular increase in computing capacities, the development of fast and robust methods describing the evolution of saturated-unsaturated soil water and solute fluxes is still a challenge. Ross (2003, Agron J; 95:1352-1361) proposed a method, solving 1D Richards' and convection-diffusion equation, that fulfil these characteristics. The method is based on a non iterative approach which reduces the numerical divergence risks and allows the use of coarser spatial and temporal discretisations, while assuring a satisfying accuracy of the results. Crevoisier et al. (2009, Adv Wat Res; 32:936-947) proposed some technical improvements and validated this method on a wider range of agro- pedo- climatic situations. In this poster, we present the simulation code WATSFAR which generalises the Ross method to other mathematical representations of soil water retention curve (i.e. standard and modified van Genuchten model) and includes a dual permeability context (preferential fluxes) for both water and solute transfers. The situations tested are those known to be the less favourable when using standard numerical methods: fine textured and extremely dry soils, intense rainfall and solute fluxes, soils near saturation, ... The results of WATSFAR have been compared with the standard finite element model Hydrus. The analysis of these comparisons highlights two main advantages for WATSFAR, i) robustness: even on fine textured soil or high water and solute

  19. 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

    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......, dedicated pumps and accessories running with sea-water as fluid are available. A unique solution is to use reverse osmosis to generate drinking water from sea-water, and furthermore for several off-shore applications. Furthermore, tap water hydraulic components of the Nessie® family and examples of measured...

  20. Atmospheric-pressure electric discharge as an instrument of chemical activation of water solutions

    Science.gov (United States)

    Rybkin, V. V.; Shutov, D. A.

    2017-11-01

    Results of experimental studies and numerical simulations of physicochemical characteristics of plasmas generated in different types of atmospheric-pressure discharges (pulsed streamer corona, gliding electric arc, dielectric barrier discharge, glow-discharge electrolysis, diaphragmatic discharge, and dc glow discharge) used to initiate various chemical processes in water solutions are analyzed. Typical reactor designs are considered. Data on the power supply characteristics, plasma electron parameters, gas temperatures, and densities of active particles in different types of discharges excited in different gases and their dependences on the external parameters of discharges are presented. The chemical composition of active particles formed in water is described. Possible mechanisms of production and loss of plasma particles are discussed.

  1. Potential of the application of the modified polysaccharides water solutions as binders of moulding sands

    Directory of Open Access Journals (Sweden)

    K. Kaczmarska

    2015-10-01

    Full Text Available The results of preliminary tests of selected properties of the moulding sands with the binder in the form of a 5 % water solution of the sodium salt of carboxymethyl starch (with a degree of substitution (DS of 0,2 and 0,87 arepresented in this study. The moulding sand properties such as permeability, abrasion resistance, tensile and bendingstrength - after curing - are shown in series of tests. The cure process was conducted in a field of electromagnetic radiation within the microwave range. The effect of the microwave treatment on the moulding sand was evaporating of water (solvent in a binder and cross-linking of the polymeric binder. As a result the cured moulding sands with particular properties, essential in the context of its application in the mould technology in the foundry industry, were obtained.

  2. Redox-Phen solution: A water equivalent dosimeter for UVA, UVB and X-rays radiation

    Science.gov (United States)

    Marini, A.; Ciribolla, C.; Lazzeri, L.; d'Errico, F.

    2018-06-01

    Polysulphone films are the only type of UV passive dosimeters that are widely adopted for research and personal monitoring. Even though many studies concentrated on the development and characterization of these films, they still present some shortcomings. The more important limitations of them are that they can measure only UVB radiations and that they change color at 330 nm, requiring special equipment to read them. To overcome these limitations we developed an aqueous dosimeter that is sensitive to UVA, UVB and X-rays named Redox-Phen solution. This dosimeter is inexpensive and water equivalent, being made of more than 99 wt% of water. It changes color in the visible region upon irradiation, thus it can be measured via simple optical method, and an evaluation of the exposition can be made also by naked eyes.

  3. Thermodynamic characteristics of the acid dissociation of dopamine hydrochloride in water-ethanol solutions

    Science.gov (United States)

    Ledenkov, S. F.; Vandyshev, V. N.; Molchanov, A. S.

    2012-06-01

    Enthalpies of the interaction of protonated dopamine with a hydroxide ion in water-ethanol mixtures in the concentration range of 0-0.8 EtOH mole fractions are measured calorimetrically. The neutralization process of dopamine hydrochloride is shown to occur endothermally in solvents with an ethanol concentration of ≥0.5 mole fractions. Standard thermodynamic characteristics (Δr H ○, Δr G ○, and Δr S ○) of the first-step acid dissociation of dopamine hydrochloride in solutions are calculated with regard to the autoprotolysis enthalpy of binary solvents. It is found that dissociation enthalpies vary within 9.1-64.8 kJ/mol, depending on the water-ethanol solvent composition.

  4. Probing ion-specific effects on aqueous acetate solutions: Ion pairing versus water structure modifications

    Directory of Open Access Journals (Sweden)

    Tristan Petit

    2014-05-01

    Full Text Available The effect of monovalent cations (Li+, K+, NH4+, Na+ on the water structure in aqueous chloride and acetate solutions was characterized by oxygen K-edge X-ray absorption spectroscopy (XAS, X-ray emission spectroscopy, and resonant inelastic X-ray scattering (RIXS of a liquid microjet. We show ion- and counterion dependent effects on the emission spectra of the oxygen K-edge, which we attribute to modifications of the hydrogen bond network of water. For acetates, ion pairing with carboxylates was also probed selectively by XAS and RIXS. We correlate our experimental results to speciation data and to the salting-out properties of the cations.

  5. Kinetics of hydrolysis of 4-methoxyphenyl-2,2-dichloroethanoate in binary water-cosolvent mixtures; the role of solvent activity and solute-solute interactions

    NARCIS (Netherlands)

    Rispens, T; Cabaleiro-Lago, C; Engberts, JBFN

    2005-01-01

    Rate constants are reported for the pH-independent hydrolysis of 4-methoxyphenyl-2,2-dichloroethanoate in aqueous solution as a function of the concentration of added cyanomethane ( acetonitrile), polyethylene glycol ( PEG 400) and tetrahydrofuran ( THF). The concentration of water was varied

  6. Aqueous pathways dominate permeation of solutes across Pisum sativum seed coats and mediate solute transport via diffusion and bulk flow of water.

    Science.gov (United States)

    Niemann, Sylvia; Burghardt, Markus; Popp, Christian; Riederer, Markus

    2013-05-01

    The permeability of seed coats to solutes either of biological or anthropogenic origin plays a major role in germination, seedling growth and seed treatment by pesticides. An experimental set-up was designed for investigating the mechanisms of seed coat permeation, which allows steady-state experiments with isolated seed coats of Pisum sativum. Permeances were measured for a set of organic model compounds with different physicochemical properties and sizes. The results show that narrow aqueous pathways dominate the diffusion of solutes across pea seed coats, as indicated by a correlation of permeances with the molecular sizes of the compounds instead of their lipophilicity. Further indicators for an aqueous pathway are small size selectivity and a small effect of temperature on permeation. The application of an osmotic water potential gradient across isolated seed coats leads to an increase in solute transfer, indicating that the aqueous pathways form a water-filled continuum across the seed coat allowing the bulk flow of water. Thus, the uptake of organic solutes across pea testae has two components: (1) by diffusion and (2) by bulk water inflow, which, however, is relevant only during imbibition. © 2012 Blackwell Publishing Ltd.

  7. Kinetics of hydrolysis of 4-methoxyphenyl-2,2-dichloroethanoate in binary water-cosolvent mixtures; the role of solvent activity and solute-solute interactions

    NARCIS (Netherlands)

    Rispens, Theo; Cabaleiro-Lago, Celia; Engberts, Jan B. F. N.

    2005-01-01

    Rate constants are reported for the pH-independent hydrolysis of 4-methoxyphenyl-2,2-dichloroethanoate in aqueous solution as a function of the concentration of added cyanomethane (acetonitrile), polyethylene glycol (PEG 400) and tetrahydrofuran (THF). The concentration of water was varied between

  8. Finite-bias electronic transport of molecules in a water solution

    KAUST Repository

    Rungger, Ivan; Chen, X.; Sanvito, Stefano; Schwingenschlö gl, Udo

    2010-01-01

    The effects of water wetting conditions on the transport properties of molecular nanojunctions are investigated theoretically by using a combination of empirical-potential molecular-dynamics and first-principles electronic-transport calculations. These are at the level of the nonequilibrium Green’s-function method implemented for self-interaction corrected density-functional theory. We find that water effectively produces electrostatic gating to the molecular junction with a gating potential determined by the time-averaged water dipole field. Such a field is large for the polar benzene-dithiol molecule, resulting in a transmission spectrum shifted by about 0.6 eV with respect to that of the dry junction. The situation is drastically different for carbon nanotubes (CNTs). In fact, because of their hydrophobic nature the gating is almost negligible so that the average transmission spectrum of wet Au/CNT/Au junctions is essentially the same as that in dry conditions. This suggests that CNTs can be used as molecular interconnects also in water-wet situations, for instance, as tips for scanning tunnel microscopy in solution or in biological sensors.

  9. Finite-bias electronic transport of molecules in a water solution

    KAUST Repository

    Rungger, Ivan

    2010-06-04

    The effects of water wetting conditions on the transport properties of molecular nanojunctions are investigated theoretically by using a combination of empirical-potential molecular-dynamics and first-principles electronic-transport calculations. These are at the level of the nonequilibrium Green’s-function method implemented for self-interaction corrected density-functional theory. We find that water effectively produces electrostatic gating to the molecular junction with a gating potential determined by the time-averaged water dipole field. Such a field is large for the polar benzene-dithiol molecule, resulting in a transmission spectrum shifted by about 0.6 eV with respect to that of the dry junction. The situation is drastically different for carbon nanotubes (CNTs). In fact, because of their hydrophobic nature the gating is almost negligible so that the average transmission spectrum of wet Au/CNT/Au junctions is essentially the same as that in dry conditions. This suggests that CNTs can be used as molecular interconnects also in water-wet situations, for instance, as tips for scanning tunnel microscopy in solution or in biological sensors.

  10. Interfacial free energy governs single polystyrene chain collapse in water and aqueous solutions.

    Science.gov (United States)

    Li, Isaac T S; Walker, Gilbert C

    2010-05-12

    The hydrophobic interaction is significantly responsible for driving protein folding and self-assembly. To understand it, the thermodynamics, the role of water structure, the dewetting process surrounding hydrophobes, and related aspects have undergone extensive investigations. Here, we examine the hypothesis that polymer-solvent interfacial free energy is adequate to describe the energetics of the collapse of a hydrophobic homopolymer chain at fixed temperature, which serves as a much simplified model for studying the hydrophobic collapse of a protein. This implies that changes in polymer-solvent interfacial free energy should be directly proportional to the force to extend a collapsed polymer into a bad solvent. To test this hypothesis, we undertook single-molecule force spectroscopy on a collapsed, single, polystyrene chain in water-ethanol and water-salt mixtures where we measured the monomer solvation free energy from an ensemble average conformations. Different proportions within the binary mixture were used to create solvents with different interfacial free energies with polystyrene. In these mixed solvents, we observed a linear correlation between the interfacial free energy and the force required to extend the chain into solution, which is a direct measure of the solvation free energy per monomer on a single chain at room temperature. A simple analytical model compares favorably with the experimental results. This knowledge supports a common assumption that explicit water solvent may not be necessary for cases whose primary concerns are hydrophobic interactions and hydrophobic hydration.

  11. Water and power for the desert -- Energy solutions for the Near and Middle East

    Energy Technology Data Exchange (ETDEWEB)

    Siersdorfer, D.

    2007-07-01

    2007 will mark a unique milestone in human history: for the first time ever, more people on earth will live and work in cities than in rural areas. Moreover, only four of the twenty biggest megacities with populations over 10 million will be in industrial nations; the others will be in threshold and developing countries. Accelerating urbanization and economic growth will fuel a massive demand for adequate infrastructures - such as power and water supplies. Reliable and economical supply of power and water to populations in regions of harsh environments, e.g. in the Near and Middle East, ensures basic survival rather than merely providing for a pleasant life. Economical supply of power and water for desert regions requires a wide mix of reliable technologies already available today and new technologies under development for future needs. Siemens Power Generation's Energy Solution Division, having proven its responsiveness in the past by playing a vital role in the development of the Near and Middle East, will continue to provide answers in future for meeting power and water demand within the regionally specific environment. (auth)

  12. Structure and dynamics of POPC bilayers in water solutions of room temperature ionic liquids

    International Nuclear Information System (INIS)

    Benedetto, Antonio; Bingham, Richard J.; Ballone, Pietro

    2015-01-01

    Molecular dynamics simulations in the NPT ensemble have been carried out to investigate the effect of two room temperature ionic liquids (RTILs), on stacks of phospholipid bilayers in water. We consider RTIL compounds consisting of chloride ([bmim][Cl]) and hexafluorophosphate ([bmim][PF 6 ]) salts of the 1-buthyl-3-methylimidazolium ([bmim] + ) cation, while the phospholipid bilayer is made of 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC). Our investigations focus on structural and dynamical properties of phospholipid and water molecules that could be probed by inelastic and quasi-elastic neutron scattering measurements. The results confirm the fast incorporation of [bmim] + into the lipid phase already observed in previous simulations, driven by the Coulomb attraction of the cation for the most electronegative oxygens in the POPC head group and by sizeable dispersion forces binding the neutral hydrocarbon tails of [bmim] + and of POPC. The [bmim] + absorption into the bilayer favours the penetration of water into POPC, causes a slight but systematic thinning of the bilayer, and further stabilises hydrogen bonds at the lipid/water interface that already in pure samples (no RTIL) display a lifetime much longer than in bulk water. On the other hand, the effect of RTILs on the diffusion constant of POPC (D POPC ) does not reveal a clearly identifiable trend, since D POPC increases upon addition of [bmim][Cl] and decreases in the [bmim][PF 6 ] case. Moreover, because of screening, the electrostatic signature of each bilayer is only moderately affected by the addition of RTIL ions in solution. The analysis of long wavelength fluctuations of the bilayers shows that RTIL sorption causes a general decrease of the lipid/water interfacial tension and bending rigidity, pointing to the destabilizing effect of RTILs on lipid bilayers

  13. Structure and dynamics of POPC bilayers in water solutions of room temperature ionic liquids

    Energy Technology Data Exchange (ETDEWEB)

    Benedetto, Antonio [School of Physics, University College Dublin, Dublin 4 (Ireland); Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institut, 5232 Villigen (Switzerland); Bingham, Richard J. [York Centre for Complex Systems Analysis, University of York, York YO10 5GE (United Kingdom); Ballone, Pietro [Center for Life Nano Science @Sapienza, Istituto Italiano di Tecnologia (IIT), 00185 Roma (Italy); Department of Physics, Università di Roma “La Sapienza,” 00185 Roma (Italy)

    2015-03-28

    Molecular dynamics simulations in the NPT ensemble have been carried out to investigate the effect of two room temperature ionic liquids (RTILs), on stacks of phospholipid bilayers in water. We consider RTIL compounds consisting of chloride ([bmim][Cl]) and hexafluorophosphate ([bmim][PF{sub 6}]) salts of the 1-buthyl-3-methylimidazolium ([bmim]{sup +}) cation, while the phospholipid bilayer is made of 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC). Our investigations focus on structural and dynamical properties of phospholipid and water molecules that could be probed by inelastic and quasi-elastic neutron scattering measurements. The results confirm the fast incorporation of [bmim]{sup +} into the lipid phase already observed in previous simulations, driven by the Coulomb attraction of the cation for the most electronegative oxygens in the POPC head group and by sizeable dispersion forces binding the neutral hydrocarbon tails of [bmim]{sup +} and of POPC. The [bmim]{sup +} absorption into the bilayer favours the penetration of water into POPC, causes a slight but systematic thinning of the bilayer, and further stabilises hydrogen bonds at the lipid/water interface that already in pure samples (no RTIL) display a lifetime much longer than in bulk water. On the other hand, the effect of RTILs on the diffusion constant of POPC (D{sub POPC}) does not reveal a clearly identifiable trend, since D{sub POPC} increases upon addition of [bmim][Cl] and decreases in the [bmim][PF{sub 6}] case. Moreover, because of screening, the electrostatic signature of each bilayer is only moderately affected by the addition of RTIL ions in solution. The analysis of long wavelength fluctuations of the bilayers shows that RTIL sorption causes a general decrease of the lipid/water interfacial tension and bending rigidity, pointing to the destabilizing effect of RTILs on lipid bilayers.

  14. A new water permeability measurement method for unsaturated tight materials using saline solutions

    International Nuclear Information System (INIS)

    Malinsky, Laurent; Talandier, Jean

    2012-01-01

    Document available in extended abstract form only. Relative water permeability of material in a radioactive waste disposal is a key parameter to simulate and predict saturation state evolution. In this paper we present a new measurement method and the results obtained for Callovo-Oxfordian (Cox) clay-stone, host rock of the underground Andra laboratory at Bure (Meuse/Haute-Marne). Relative water permeability of such a low permeability rock as Cox clay-stone has been measured up to now by an indirect method. It consists in submitting a rock sample to successive relative humidity steps imposed by saline solutions. The transient mass variation during each step and the mass at hydric equilibrium are interpreted generally by using an inverse analysis method. The water relative permeability function of water saturation is derived from water diffusion coefficient evolution and water retention curve. The proposed new method consists in directly measuring the water flux across a flat cylindrical submitted to a relative humidity gradient. Two special cells have been developed. The tightness of the lateral sample surface is insured by crushing a polyurethane ring surrounding the sample set in an aluminium device placed over a Plexiglas vessel filled with a saline solution. One of the cells is designed to allow humidity measurement in the cell. These cells can also be used to measure the relative humidity produced by a saline solution or by an unsaturated material. During a permeability measurement, the cell with the sample to be tested is continuously weighted in a Plexiglas box in which a saline solution imposes a different relative humidity at the upper sample face. The experimental set-up is shown on Figure 1. The mean permeability of the sample is proportional to the rate of mass variation when steady state is reached. The result of one test is shown on Figure 2(a). Twenty four permeability measurements have been performed on four argillite samples of 15 mm in height and

  15. Prague’s Water Supply Station in Podolí — a Solution for the Problems of Clean Water in the 1930s

    Directory of Open Access Journals (Sweden)

    K. Drnek

    2011-01-01

    Full Text Available In the 1920s Prague was seeking a solution to the problem of supplying its inhabitants with drinkable water. The water plant in Káraný was not able to provide enough water, and the bold plan to bring water from a reservoir and to provide a dual system of potable and non-potable water faced an uncertain future. In order to stave off the crisis and make time to complete its plans, the city council decided to construct a new water supply plant inside the city next to the Vltava river in the city district of Podolí.

  16. Market-Driven Solutions to Economic, Environmental, and Social Issues Related to Water Management in the Western USA

    Directory of Open Access Journals (Sweden)

    Jordan A. Clayton

    2009-10-01

    Full Text Available Water management issues continue to plague the western United States, including rapid population growth, degraded aquatic ecosystems, unfulfilled claims to American Indian users, the threat of global warming, an economic recession, and many other issues. This essay outlines some advantages of market-driven reforms to the management of water resources in the western USA. Historical and contemporary western water resource issues are examined from economic, environmental, and social viewpoints. In all such contexts, it is argued that regulated water markets provide flexible and just solutions to western water dilemmas, and reallocations may provide much-needed additional water supply.

  17. The SOLUTIONS project : Challenges and responses for present and future emerging pollutants in land and water resources management

    NARCIS (Netherlands)

    Brack, Werner; Altenburger, Rolf; Schüürmann, Gerrit; Krauss, Martin; López Herráez, David; van Gils, Jos; Slobodnik, Jaroslav; Munthe, John; Gawlik, Bernd Manfred; van Wezel, Annemarie|info:eu-repo/dai/nl/141376074; Schriks, Merijn; Hollender, Juliane; Tollefsen, Knut Erik; Mekenyan, Ovanes; Dimitrov, Saby; Bunke, Dirk; Cousins, Ian; Posthuma, Leo; van den Brink, Paul J.; López de Alda, Miren; Barceló, Damià; Faust, Michael; Kortenkamp, Andreas; Scrimshaw, Mark; Ignatova, Svetlana; Engelen, Guy; Massmann, Gudrun; Lemkine, Gregory; Teodorovic, Ivana; Walz, Karl Heinz; Dulio, Valeria; Jonker, Michiel T O|info:eu-repo/dai/nl/175518793; Jäger, Felix; Chipman, Kevin; Falciani, Francesco; Liska, Igor; Rooke, David; Zhang, Xiaowei; Hollert, Henner; Vrana, Branislav; Hilscherova, Klara; Kramer, Kees; Neumann, Steffen; Hammerbacher, Ruth; Backhaus, Thomas; Mack, Juliane; Segner, Helmut; Escher, Beate; de Aragão Umbuzeiro, Gisela

    2015-01-01

    SOLUTIONS (2013 to 2018) is a European Union Seventh Framework Programme Project (EU-FP7). The project aims to deliver a conceptual framework to support the evidence-based development of environmental policies with regard to water quality. SOLUTIONS will develop the tools for the identification,

  18. The SOLUTIONS project: Challenges and responses for present and future emerging pollutants in land and water resources management

    NARCIS (Netherlands)

    Brack, W.; Altenburger, R.; Schuurmann, G.; Krauss, M.; Brink, van den P.J.

    2015-01-01

    SOLUTIONS (2013 to 2018) is a European Union Seventh Framework Programme Project (EU-FP7). The project aims to deliver a conceptual framework to support the evidence-based development of environmental policies with regard to water quality. SOLUTIONS will develop the tools for the identification,

  19. A water-cooling solution for PC-racks of the LHC experiments

    CERN Document Server

    Vannerem, P

    2004-01-01

    With ever increasing power consumption and heat dissipation of todays CPUs, cooling of rack-mounted PCs is an issue for the future online farms of the LHC experiments. In order to investigate the viability of a water-cooling solution, a prototype PC-farm rack has been equipped with a commercially available retrofitted heat exchanger. The project has been carried out as a collaboration of the four LHC experiments and the PH-ESS group . This note reports on the results of a series of cooling and power measurements of the prototype rack with configurations of 30 to 48 PCs. The cooling performance of the rack-cooler is found to be adequate; it extracts the heat dissipated by the CPUs efficiently into the cooling water. Hence, the closed PC rack transfers almost no heat into the room. The measurements and the failure tests show that the rack-cooler concept is a viable solution for the future PC farms of the LHC experiments.

  20. Liquid-microjet synchrotron-radiation spectroscopy for biomolecules in water solution 1

    International Nuclear Information System (INIS)

    Ukai, Masatoshi; Shimada, Hiroyuki

    2012-01-01

    A new spectroscopic research of radiation induced damage on DNA and its constituent molecules is proposed, which is made possible using a liquid micro-jet technique for bio-solution under vacuum in combination with synchrotron-radiation aided site-selective excitation. We emphasize a view point of time-evolutional production and destruction of irregular chemical species characteristic of time domains after irradiation, which finally result in the alternative processes to give rise to a irreparable damage or to avoid it by a thermodynamical restoration. Up to now a method of spectroscopy to identify the initial molecular site of radiation interaction is almost completed. The former part of the proposal article is presented in this volume. We describe the objectives of the new spectroscopy for observing the early processes of direct radiation effect on DNA leading to damage induction using a site-selective synchrotron-radiation excitation to identify the initial site of radiation interaction. The present status of development is described by presenting the new results of the spectra of X-ray absorption near edge structure and ejected electron energy spectra for liquid water as examples. The forthcoming latter part of this article will discuss the conformational and electronic structure of nucleotides in water solution prior to time evolution. (author)

  1. Volumetric properties of MES, MOPS, MOPSO, and MOBS in water and in aqueous electrolyte solutions

    International Nuclear Information System (INIS)

    Taha, Mohamed; Lee, Ming-Jer

    2010-01-01

    4-Morpholineethanesulfonic acid (MES), 4-morpholinepropanesulfonic acid (MOPS), 3-morpholino-2-hydroxypropanesulfonic acid (MOPSO), and 4-(N-morpholino)butanesulfonic acid (MOBS), are useful for pH control as standard buffers in the physiological region of 5.5-6.7 for MES, 6.5-7.9 for MOPS, 6.2-7.6 for MOPSO, and 6.9-8.3 for MOBS, respectively. On the basis of density measurements at 298.15 K, the apparent molar volumes, V φ , of the above-mentioned buffers in water and in (0.05, 0.16, and 0.25) mol kg -1 aqueous solutions of NaCl, KCl, KBr, and CH 3 COOK have been calculated. The partial molar volumes at infinite dilution, V φ o , obtained from V φ , have been used to calculate the volume of transfer, Δ tr V φ o , from water to aqueous electrolyte solutions. It was found that both V φ o and Δ tr V φ o vary linearly with increasing the number of carbon atoms in the alkyl group side chain of the zwitterionic buffers. These linear correlations have been utilized to estimate the contributions of the zwitterionic end group (morpholinium ion, -SO 3 - ) and -CH 2 - group to V φ o and Δ tr V φ o . The values of V φ o and Δ tr V φ o for some functional group contributions of the zwittierionic buffers with salts have also been reported.

  2. (Liquid + liquid) phase equilibrium and critical behavior of binary solution {heavy water + 2,6-dimethylpyridine}

    International Nuclear Information System (INIS)

    Xu, Chen; Chai, Shouning; Yin, Tianxiang; Chen, Zhiyun; Shen, Weiguo

    2015-01-01

    Highlights: • Coexistence curves, heat capacities and turbidities were measured. • Deuterium effect on coexistence curves was discussed. • Universal critical amplitude ratios were tested. • Asymmetry of coexistence curves was analyzed by the complete scaling theory. - Abstract: The (liquid + liquid) coexistence curves, the isobaric heat capacities per unit volume and the turbidities for the binary solution of {heavy water + 2,6-dimethylpyridine} have been precisely measured. The values of the critical exponents were obtained, which confirmed the 3D-Ising universality. It was found that the critical temperature dropped by 5.9 K and the critical amplitude of the coexistence curve significantly increased as compared to the binary solution of {water + 2,6-dimethylpyridine}. The complete scaling theory was applied to well describe the asymmetric behavior of the diameter of the coexistence curve as the heat capacity contribution was considered. Moreover, the values of the critical amplitudes of the correlation length and the osmotic compressibility were deduced, which together with the critical amplitudes of the coexistence curve and the heat capacity to test universal amplitude ratios

  3. Small angle neutron scattering study of the gemini nonionic surfactant in heavy water solutions

    International Nuclear Information System (INIS)

    Rajewska, A

    2012-01-01

    The nonionic gemini surfactant α α'-[2,4,7,9-tetramethyl-5-decyne-4,7diyl]bis[ω hydroxyl-polyoxyethylene] (S-10) was investigated in heavy water solutions only for concentrations: 2.3%, 2.5%,3%, 3.4%, 4% and 5% at temperature 25 C with small angle neutron scattering (SANS) method. All of surfactants solutions were prepared using D 2 O (99.9% deuterated, Prikladnaia Chimia, St. Petersburg, Russia) as a solvent. The nonionic gemini surfactant S-10 was obtained from Air Products and Chemicals, Inc., and used without further purification. All SANS measurements were performed on V-4 SANS spectrometer at BENSC, Berlin (Germany). Neutrons were used in wavelength range of 0.02 - 4 nm - 1. For the measurements quartz cells of were used during experiment. Up to 14 such cells were placed in a holder. Results from experiment was calculated and evaluated with PCG 2.0 program from Graz University (Austria). In the investigated solutions two axis ellipsoidal micelles was observed.

  4. Quasielastic scattering of slow-neutron in water-alcohol solutions

    Directory of Open Access Journals (Sweden)

    N. O. Atamas

    2010-06-01

    Full Text Available Research of molecules dynamics of solutionswater - propyl alcohol” of different concentration at the temperature 281 K is conducted by the method of slow-neutron quasi-elastic scattering. There were experimentally exposed the feature of effective self-diffusion coefficient of molecules of the indicated solutions. Based on the time- scale hierarchy the division of selfdiffusion coefficient to one-particle and collective contributions was conducted, and the time of the molecules settled life in position of equilibrium was calculated. There were also exposed the feature of self-diffusion concentration dependence of coefficient of self-diffusion and his selfpart contribution, namely: presence of two minimums is in the areas of concentrations (0,04 ÷ 0,05 of mass fraction and (0,18 ÷ 0,22 m.c. of the alcohol and continuous character of diffusion at concentrations higher then 0,4 m.c. of the alcohol. It is shown that the indicated concentration areas correspond the certain local structures of investigational solution.

  5. Investigating effects of hypertonic saline solutions on lipid monolayers at the air-water interface

    KAUST Repository

    Nava Ocampo, Maria F.

    2017-05-01

    More than 70,000 people worldwide suffer from cystic fibrosis, a genetic disease characterized by chronic accumulation of mucus in patients’ lungs provoking bacterial infections, and leading to respiratory failure. An employed age-old treatment to prevent the symptoms of the disease is inhalation of hypertonic saline solution, NaCl at concentrations higher than in the human body (~150 mM). This procedure clears the mucus in the lungs, bringing relief to the patient. However, the biophysical mechanisms underlying this process are not entirely clear. We undertook a new experimental approach to understand the effects of sprayed saline solutions on model lung surfactants towards understanding the mechanisms of the treatment. The surface of lungs contains mainly 1,2-Dipalmitol-sn-glycero-3-phosphocoline (DPPC). As previously assumed by others, we considered that monolayer of DPPC at the air-water interface serves as model system for the lungs surface; we employed a Langmuir-Blodgett (LB) trough and PM-IRRAS to measure surface-specific infrared spectra of the surfactant monolayers and effects on the interfacial tensions. We investigated spraying hyper-saline solutions onto surfactant monolayers at the airwater interface in two parts: (i) validation of our methodology and techniques with stearic acid and (ii) experiments with DPPC monolayers at the air-water interface. Remarkably, when micro-droplets of NaCl were sprayed to the monolayer of stearic acid, we observed enhanced organization of the surfactant, interpreted from the intensities of the CH2 peaks in the surface-specific IR spectra. However, our results with DPPC monolayers didn’t show an effect with the salt added as aerosol, possibly indicating that the experimental methodology proposed is not adequate for the phenomena studied. In parallel, we mimicked respiratory mucous by preparing salt solutions containing 1% (wt%) agar and measured effects on their viscosities. Interestingly, we found that NaCl was much

  6. PHAST--a program for simulating ground-water flow, solute transport, and multicomponent geochemical reactions

    Science.gov (United States)

    Parkhurst, David L.; Kipp, Kenneth L.; Engesgaard, Peter; Charlton, Scott R.

    2004-01-01

    The computer program PHAST simulates multi-component, reactive solute transport in three-dimensional saturated ground-water flow systems. PHAST is a versatile ground-water flow and solute-transport simulator with capabilities to model a wide range of equilibrium and kinetic geochemical reactions. The flow and transport calculations are based on a modified version of HST3D that is restricted to constant fluid density and constant temperature. The geochemical reactions are simulated with the geochemical model PHREEQC, which is embedded in PHAST. PHAST is applicable to the study of natural and contaminated ground-water systems at a variety of scales ranging from laboratory experiments to local and regional field scales. PHAST can be used in studies of migration of nutrients, inorganic and organic contaminants, and radionuclides; in projects such as aquifer storage and recovery or engineered remediation; and in investigations of the natural rock-water interactions in aquifers. PHAST is not appropriate for unsaturated-zone flow, multiphase flow, density-dependent flow, or waters with high ionic strengths. A variety of boundary conditions are available in PHAST to simulate flow and transport, including specified-head, flux, and leaky conditions, as well as the special cases of rivers and wells. Chemical reactions in PHAST include (1) homogeneous equilibria using an ion-association thermodynamic model; (2) heterogeneous equilibria between the aqueous solution and minerals, gases, surface complexation sites, ion exchange sites, and solid solutions; and (3) kinetic reactions with rates that are a function of solution composition. The aqueous model (elements, chemical reactions, and equilibrium constants), minerals, gases, exchangers, surfaces, and rate expressions may be defined or modified by the user. A number of options are available to save results of simulations to output files. The data may be saved in three formats: a format suitable for viewing with a text editor; a

  7. An expanded conceptual framework for solution-focused management of chemical pollution in European waters.

    Science.gov (United States)

    Munthe, John; Brorström-Lundén, Eva; Rahmberg, Magnus; Posthuma, Leo; Altenburger, Rolf; Brack, Werner; Bunke, Dirk; Engelen, Guy; Gawlik, Bernd Manfred; van Gils, Jos; Herráez, David López; Rydberg, Tomas; Slobodnik, Jaroslav; van Wezel, Annemarie

    2017-01-01

    This paper describes a conceptual framework for solutions-focused management of chemical contaminants built on novel and systematic approaches for identifying, quantifying and reducing risks of these substances. The conceptual framework was developed in interaction with stakeholders representing relevant authorities and organisations responsible for managing environmental quality of water bodies. Stakeholder needs were compiled via a survey and dialogue. The content of the conceptual framework was thereafter developed with inputs from relevant scientific disciplines. The conceptual framework consists of four access points: Chemicals, Environment, Abatement and Society, representing different aspects and approaches to engaging in the issue of chemical contamination of surface waters. It widens the scope for assessment and management of chemicals in comparison to a traditional (mostly) perchemical risk assessment approaches by including abatement- and societal approaches as optional solutions. The solution-focused approach implies an identification of abatement- and policy options upfront in the risk assessment process. The conceptual framework was designed for use in current and future chemical pollution assessments for the aquatic environment, including the specific challenges encountered in prioritising individual chemicals and mixtures, and is applicable for the development of approaches for safe chemical management in a broader sense. The four access points of the conceptual framework are interlinked by four key topics representing the main scientific challenges that need to be addressed, i.e.: identifying and prioritising hazardous chemicals at different scales; selecting relevant and efficient abatement options; providing regulatory support for chemicals management; predicting and prioritising future chemical risks. The conceptual framework aligns current challenges in the safe production and use of chemicals. The current state of knowledge and implementation

  8. Apparent molal volumes of HMT and TATD in aqueous solutions around the temperature of maximum density of water

    International Nuclear Information System (INIS)

    Clavijo Penagos, J.A.; Blanco, L.H.

    2012-01-01

    Highlights: ►V φ for HMT and TATD in aqueous solutions around the temperature of maximum density of water are reported. ► V φ is linear in m form m = 0.025 for all the aqueous solutions investigated. ► Variation of V ¯ 2 ∞ with T obeys a second grade polynomial trend. ► The solutes are classified as structure breakers according to Hepler’s criterion. - Abstract: Apparent molal volumes V φ have been determined from density measurements for several aqueous solutions of 1,3,5,7-tetraazatricyclo[3.3.1.1(3,7)]decane (HMT) and 1,3,6,8-tetraazatricyclo[4.4.1.1(3,8)]dodecane (TATD) at T = (275.15, 275.65, 276.15, 276.65, 277.15, 277.65 and 278.15) K as function of composition. The infinite dilution partial molar volumes of solutes in aqueous solution are evaluated through extrapolation. Interactions of the solutes with water are discussed in terms of the effect of the temperature on the volumetric properties and the structure of the solutes. The results are interpreted in terms of water structure-breaking or structure forming character of the solutes.

  9. Heat Transfer from Optically Excited Gold Nanostructures into Water, Sugar, and Salt Solutions

    Science.gov (United States)

    Green, Andrew J.

    coherence length associated with the liquid-liquid transition. The second topic will measure the change in heat dissipation with respect to solute adhesion onto the nanoheater. A small amount of aqueous solute molecules (1 solute molecule in 550 water molecules) dramatically increases the heat dissipation from a nanoparticle into the surrounding liquid. This result is consistent with a thermal conductance that is limited by an interface interaction where minority aqueous components significantly alter the surface properties and heat transport through the interface. The increase in heat dissipation can be used to make an extremely sensitive molecular detector that can be scaled to give single molecule detection without amplification or utilizing fluorescence labels.

  10. Long-term solute diffusion in a granite block immersed in sea water

    International Nuclear Information System (INIS)

    Jefferies, N.L.

    1988-01-01

    Solute diffusion profiles for Cl - , Br - , F - and SO 4 -- have been measured in a granite block which was immersed in the sea at Falmouth, Cornwall, for 30 years. Leachable concentrations of Cl - and Br - were found to be higher in the block than in quarry samples of granite, which demonstrates that solutes from the sea water have diffused into the block. The Cl - and Br - profiles within the block were flat, implying that equilibrium has been reached between the seawater and granite porewater. The apparent diffusion coefficient and the solute accessible porosity have been estimated from these profiles, and these were used to calculate the intrinsic diffusion coefficient which was then compared with previously obtained laboratory data. Concentration profiles for F - and S0 4 -- indicate that these elements have high concentrations at the margins of the block (to depths of up to 15 cm) and are in the process of diffusing outwards into the surrounding seawater. The initially high porewater concentrations of F - and SO 4 -- in the block are believed to result from weathering of the granite prior to its immersion in the sea, due to the breakdown of primary minerals such as pyrite and the micas. F - and SO 4 -- sorptivity has been estimated from an analysis of the porewater concentration profiles. This preliminary experiment has demonstrated the potential for the measurement of solute migration in granite, as a result of the rock having been immersed in seawater. This work is part of the CEC project MIRAGE (radionuclide migration in the geosphere)- Second phase (1985-89) Research area 'Natural analogues'

  11. Dalia integrated production bundle (IPB): an innovative riser solution for deep water fields

    Energy Technology Data Exchange (ETDEWEB)

    Reals, Th Boscals de; Gloaguen, M.; Roche, F. [Total E and P (Angola); Marion, A.; Poincheval, A. [Technip, Paris (France)

    2008-07-01

    The Dalia field is located 210 km north west of Luanda (Angola), about 140 km from shore in 1400 meter water-depth. It was the second major discovery out of 15 made in the block 17 operated by Total. The Dalia Umbilical, Flow lines and Risers EPCI Contract was awarded in 2003. The sea-line network to connect and control the 71 wells and 9 manifolds consist of the following: 40 km of insulated pipe in pipe (12 inches into 17 inches) production flow lines; 45 km of 12 inches water and gas injection lines; 6 off 1.7 km flexible water and gas injection risers; 8 off 1.65 km flexible Integrated Production Bundle (IPB) risers; 75 km of control umbilicals. The flow assurance and associated insulation requirement of the production transport system was one of the main challenges of the project. With a crude temperature of 45 deg C at the wellhead and the required minimum temperature of 35 deg C on arrival at the FPSO, this problem was complex. Understanding that, due to the Joule Thompson effect of the riser gas lift, a 'built in' loss of about 5 deg C is induced and together with further losses through the sub sea pipelines, some up to 6 km long, the agreed solution was 'pipe in pipe' for the production flow lines. The innovative flexible IPB riser, incorporating gas lift and heating to keep the fluid temperature above hydrate formation zone, was the selected riser solution. The IPB is new technology for deep water, developed by Technip for Dalia, and consists of a 12 inches nominal central flexible, surrounded by layers of heat tracing cables, small bore gas lift lines, optical fibres and many insulation layers with an Overall Heat Transfer Coefficient of approximately 3,4 W/m{sup 2}K. After an earlier research and development programme, a further extensive qualification programme was conducted during the course of the project, culminating with the deep water testing phase offshore Brazil. The IPB was then approved for fabrication and installation

  12. The impact of kosmotropes and chaotropes on bulk and hydration shell water dynamics in a model peptide solution

    International Nuclear Information System (INIS)

    Russo, Daniela

    2008-01-01

    Kosmotropic (order-making) and chaotropic (order-breaking) co-solvents influence stability and biochemical equilibrium in aqueous solutions of proteins, acting indirectly through the structure and dynamics of the hydration water that surrounds the protein molecules. We have investigated the influence of kosmotropic and chaotropic co-solvents on the hydrogen bonding network dynamics of both bulk water and hydration water. To this end the evolution of bulk water and hydration water dynamics of a prototypical hydrophobic amino acid with polar backbone, N-acetyl-leucine-methylamide (NALMA), has been studied by quasielastic neutron scattering as a function of solvent composition. The results show that bulk water and hydration water dynamics, apart from a dynamical suppression that depends on the NALMA solute, exhibit the same dependence on addition of co-solvent for all of the co-solvents studied (urea, glycerol, MgSO 4 , and dimethyl sulfoxide). The hydrophobic solute and the high concentration water-structuring additive have the same effect on the water hydrogen bonding network. Water remains the preferential hydration of the hydrophobic side chain and backbone. We also find that the reorganization of the bulk water hydrogen bond network, upon addition of kosmotrope and chaotrope additives, is not dynamically perturbed, and that the hydrogen bond lifetime is maintained at 1 ps as in pure bulk water. On the other hand the addition of NALMA to the water/co-solvent binary system causes reorganization of the hydrogen bonds, resulting in an increased hydrogen bond lifetime. Furthermore, the solute's side chain dynamics is not affected by high concentrations of co-solvent. We shall discuss the hydration dynamics results in the context of protein folding and protein-solvent interactions

  13. Solute's perspective on how trimethylamine oxide, urea, and guanidine hydrochloride affect water's hydrogen bonding ability.

    Science.gov (United States)

    Pazos, Ileana M; Gai, Feng

    2012-10-18

    While the thermodynamic effects of trimethylamine oxide (TMAO), urea, and guanidine hydrochloride (GdnHCl) on protein stability are well understood, the underlying mechanisms of action are less well characterized and, in some cases, even under debate. Herein, we employ the stretching vibration of two infrared (IR) reporters, i.e., nitrile (C≡N) and carbonyl (C═O), to directly probe how these cosolvents mediate the ability of water to form hydrogen bonds with the solute of interest, e.g., a peptide. Our results show that these three agents, despite having different effects on protein stability, all act to decrease the strength of the hydrogen bonds formed between water and the infrared probe. While the behavior of TMAO appears to be consistent with its protein-protecting ability, those of urea and GdnHCl are inconsistent with their role as protein denaturants. The latter is of particular interest as it provides strong evidence indicating that although urea and GdnHCl can perturb the hydrogen-bonding property of water their protein-denaturing ability does not arise from a simple indirect mechanism.

  14. Immobilization of zinc from metallurgical waste and water solutions using geopolymerization technology

    Directory of Open Access Journals (Sweden)

    Nikolići I.

    2014-07-01

    Full Text Available Geopolymeraization technology is recognized as a promising method for immobilization of heavy metals by the stabilization or solidification process. This process involves the chemical reaction of alumino-silicate oxides with highly alkaline activator yielding the new material with amorphous or semi-amorphous structure, called geopolymer. Fly ash and blast furnace slag were mainly used as a raw material for geopolymerization process. In this paper we have investigated the possibility of immobilization of Zn from electric arc furnace dust (EAFD through geopolymerization of fly ash and possibility of Zn2+ adsorption from waste waters using fly ash based geopolymers. Efficacy of Zn immobilization from electric arc furnace dust was evaluated by TCLP test while the immobilization of Zn2+ ions from the water solution was evaluated through the removal efficiency. The results have shown that geopolymerization process may successfully be used for immobilization of Zn by stabilization of EAFD and for production of low cost adsorbent for waste water treatment.

  15. Heating homes and water with the sun. Solar thermal solutions adapted to individual homes

    International Nuclear Information System (INIS)

    Bareau, Helene; Juniere, Olivier; Leplay, Camille

    2016-09-01

    This brochure, edited by ADEME, the French office for energy management and sustainable development, gives a basic outlook of the way to complete the installation of a solar space and hot water heating system in an individual home. After some recall of the key points to be considered before taking the decision to invest in a solar heating system (minimum surface, orientation, etc.) and the main administrative procedures to be respected (in France), this document presents the common individual solar water heating system (which is now reliable and robust), its various equipment and operating principles, the dimensioning of the system, gives recommendations on points such as the panel position and orientation, the risk of overheating and the way to avoid it, etc. It also presents combined solar heating solutions that simultaneously heat water and space, their operating principles and the way to complete their installation for a home. Informations on financing, selection of the equipment and the installer, and installation maintenance are also proposed

  16. How Subsurface Water Technologies (SWT) can Provide Robust, Effective, and Cost-Efficient Solutions for Freshwater Management in Coastal Zones

    NARCIS (Netherlands)

    Zuurbier, K.G.; Raat, K.J.; Paalman, M.; Oosterhof, A.T.; Stuyfzand, P.J.

    2016-01-01

    Freshwater resources in coastal zones are limited while demands are high, resulting in problems like seasonal water shortage, overexploitation of freshwater aquifers, and seawater intrusion. Three subsurface water technologies (SWT) that can provide robust, effective, and cost-efficient solutions to

  17. Motor Neurons

    DEFF Research Database (Denmark)

    Hounsgaard, Jorn

    2017-01-01

    Motor neurons translate synaptic input from widely distributed premotor networks into patterns of action potentials that orchestrate motor unit force and motor behavior. Intercalated between the CNS and muscles, motor neurons add to and adjust the final motor command. The identity and functional...... in in vitro preparations is far from complete. Nevertheless, a foundation has been provided for pursuing functional significance of intrinsic response properties in motoneurons in vivo during motor behavior at levels from molecules to systems....

  18. Thousand Islands River : study of solutions to address critically low water levels : summary report; Riviere des Milles Iles : etude des solutions de soutien des etiages critiques : rapport sommaire

    Energy Technology Data Exchange (ETDEWEB)

    Cyr, J F; Fontin, M [Centre d' Expertise Hydrique du Quebec, Quebec, PQ (Canada). Service de la Securite des Barrages

    2005-07-01

    A study was conducted to find solutions to very low water flow in the Thousand Islands River, near the Island of Montreal, Quebec. It was launched in response to the critically low water levels that were experienced in 2001 and 2002. In the summer of 2001, municipalities served by the Thousand Island River were faced with problems in the supply of drinking water when the river flow reached approximately 13 cubic metres per second. Since 1970, the minimal values of flow observed for this time of year had seldom passed under 20 cubic metres per second. Under such conditions of flow, the dilution of any water discharged into the river became so weak that the aging water treatment facilities had to work beyond their capacity. In addition, the population served by this river has increased significantly in the past 2 decades. During this episode of critically low water levels, Quebec's Center of Water Expertise (CEHQ)intervened in an emergency measure to drain flows from a water reservoir in the catchment area to ensure a minimal flow of approximately 25 cubic metres per second. Thereafter, the affected municipalities had to ask the Quebec Environment Ministry to define permanent interventions to ensure a minimal flow the river in the event of similar episodes. The CEHQ carried out a preliminary study of possible solutions to address the critically low water levels and presented its report in the spring 2002. In the winter of 2002, CEHQ created an emergency management procedure in preparation of a repeat episode. 28 refs., 11 figs.

  19. Thousand Islands River : study of solutions to address critically low water levels : summary report; Riviere des Milles Iles : etude des solutions de soutien des etiages critiques : rapport sommaire

    Energy Technology Data Exchange (ETDEWEB)

    Cyr, J.F.; Fontin, M. [Centre d' Expertise Hydrique du Quebec, Quebec, PQ (Canada). Service de la Securite des Barrages

    2005-07-01

    A study was conducted to find solutions to very low water flow in the Thousand Islands River, near the Island of Montreal, Quebec. It was launched in response to the critically low water levels that were experienced in 2001 and 2002. In the summer of 2001, municipalities served by the Thousand Island River were faced with problems in the supply of drinking water when the river flow reached approximately 13 cubic metres per second. Since 1970, the minimal values of flow observed for this time of year had seldom passed under 20 cubic metres per second. Under such conditions of flow, the dilution of any water discharged into the river became so weak that the aging water treatment facilities had to work beyond their capacity. In addition, the population served by this river has increased significantly in the past 2 decades. During this episode of critically low water levels, Quebec's Center of Water Expertise (CEHQ)intervened in an emergency measure to drain flows from a water reservoir in the catchment area to ensure a minimal flow of approximately 25 cubic metres per second. Thereafter, the affected municipalities had to ask the Quebec Environment Ministry to define permanent interventions to ensure a minimal flow the river in the event of similar episodes. The CEHQ carried out a preliminary study of possible solutions to address the critically low water levels and presented its report in the spring 2002. In the winter of 2002, CEHQ created an emergency management procedure in preparation of a repeat episode. 28 refs., 11 figs.

  20. Mechanism of the extraction of nitric acid and water by organic solutions of tertiary alkyl-amines

    International Nuclear Information System (INIS)

    Gourisse, D.

    1966-06-01

    The micellar aggregation of tri-alkyl-ammonium nitrates in low polarity organic solvents has been verified by viscosity, conductivity and sedimentation velocity measurements. The aggregation depends upon the polarity of solvent, the length of the alkyl radicals and the organic concentration of the various constituents (tri-alkyl-ammonium nitrate, tri-alkyl-amine, nitric acid, water). The amine salification law has been established and the excess nitric acid and water solubilities in the organic solutions have been measured. Nitric acid and water are slightly more soluble in micellar organic solutions than in molecular organic solutions. A description of excess nitric acid containing tri-alkyl-ammonium nitrate solutions is proposed. (author) [fr

  1. Derivation of an empirical formula for determining water content of mixed uranyl nitrate-thorium nitrate solutions

    International Nuclear Information System (INIS)

    Min, Duck Kee; Choi, Byung Il; Ro, Seung Gy; Eom, Tae Yoon; Kim, Zong Goo

    1986-01-01

    Densities of a large number of mixed uranyl nitrate-thorium nitrate solutions were measured with pycnometer. By the least squares analysis of the experimental result, an empirical formula for determining water content of mixed uranyl nitrate-thorium nitrate solutions as functions of uranium concentration, thorium concentration and nitric acid normality is derived; W=1.0-0.3580 C u -0.4538 C Th -0.0307H + where W, C u , C Th , and H + stand for water content(g/cc), uranium concentration (g/cc), thorium concentration(g/cc), and nitric acid normality, respectively. Water contents of the mixed uranyl nitrate-thorium nitrate solutions are calculated by using the empirical formular, and compared with the values calculated by Bouly's equation in which an additional data, solution density, is required. The two results show good agreements within 2.7%. (Author)

  2. Effect of Solution Properties on Arsenic Adsorption by Drinking Water Treatment Residuals

    Science.gov (United States)

    Nagar, R.; Sarkar, D.; Datta, R.; Sharma, S.

    2005-05-01

    Arsenic (As) is a ubiquitous element in the environment. Higher levels of As in soils may result from various anthropogenic sources such as use of arsenical pesticides, fertilizers, wood preservatives, smelter wastes, and coal combustion. This is of great environmental and human health concern due to the high toxicity and proven carcinogenicity of several arsenical species. Thus there is a need for developing cost effective technologies capable of lowering bioavailable As concentrations in soils to environmentally acceptable levels. In-situ immobilization of metals using inexpensive amendments such as minerals (apatite, zeolite, or clay minerals) or waste by-products (steel shot, beringite, and iron-rich biosolids) to reduce bioavailability is an inexpensive alternative to the more expensive ex-situ remediation methods. One such emerging in-situ technique is the application of drinking water treatment residuals (WTRs). WTRs can be classified as a byproduct of drinking water treatment plants and are generally composed of amorphous Fe/Al oxides, activated C and cationic polymers. WTRs possess amorphous structure and generally have high positive charge. Because As is chemically similar to phosphorus, the oxyanions As (V) and As (III) may have the potential of being retained by the WTRs. Thus, it is hypothesized that WTRs retain As irreversibly, thereby reducing As biavailability. As mobility of arsenic is controlled by adsorption reactions, knowledge of adsorption of As by WTRs is of primary relevance. Although the overall rate of adsorption is dependent on numerous factors, review of the literature indicates that competing ions in solution play an important role in the overall retention of As; however, little work has been conducted to identify which ions provide the most competition. As arsenic adsorption appears to be influenced by the variable pH-dependent charges developed on the soil particle surfaces, the effect of pH is also of critical importance. Hence, the

  3. Correlation and prediction of osmotic coefficient and water activity of aqueous electrolyte solutions by a two-ionic parameter model

    International Nuclear Information System (INIS)

    Pazuki, G.R.

    2005-01-01

    In this study, osmotic coefficients and water activities in aqueous solutions have been modeled using a new approach based on the Pitzer model. This model contains two physically significant ionic parameters regarding ionic solvation and the closest distance of approach between ions in a solution. The proposed model was evaluated by estimating the osmotic coefficients of nine electrolytes in aqueous solutions. The obtained results showed that the model is suitable for predicting the osmotic coefficients in aqueous electrolyte solutions. Using adjustable parameters, which have been calculated from regression between the experimental osmotic coefficient and the results of this model, the water activity coefficients of aqueous solutions were calculated. The average absolute relative deviations of the osmotic coefficients between the experimental data and the calculated results were in agreement

  4. Water solubilization and the dielectric permeability of isomolar solutions of oleic acid and triethanolamine soap of oleic acid

    Energy Technology Data Exchange (ETDEWEB)

    Demchenko, P.A.; Novitskaya, L.D.

    The investigation of the dependence of water solubilization on the dielectric permeability of isomolar solutions of oleic acid and triethanolamine soap of oleic acid in benzene has shown that at certain acid additions, the solubilization effect can increase almost 6 times, as compared to the soap solution without acid additions. In some cases, electron donor-acceptor complexes are formed, which are more polar than the original components. This leads to a change in the molecular-disperse and micellar part of solution and affects significantly the structure and properties of micellar hydrocarbon solutions of surfactants.

  5. Influence of convection on the diffusive transport and sieving of water and small solutes across the peritoneal membrane.

    Science.gov (United States)

    Asghar, Ramzana B; Diskin, Ann M; Spanel, Patrik; Smith, David; Davies, Simon J

    2005-02-01

    The three-pore model of peritoneal membrane physiology predicts sieving of small solutes as a result of the presence of a water-exclusive pathway. The purpose of this study was to measure the diffusive and convective components of small solute transport, including water, under differing convection. Triplicate studies were performed in eight stable individuals using 2-L exchanges of bicarbonate buffered 1.36 or 3.86% glucose and icodextrin. Diffusion of water was estimated by establishing an artificial gradient of deuterated water (HDO) between blood/body water and the dialysate. (125)RISA (radio-iodinated serum albumin) was used as an intraperitoneal volume marker to determine the net ultrafiltration and reabsorption of fluid. The mass transfer area coefficient (MTAC) for HDO and solutes was estimated using the Garred and Waniewski equations. The MTAC of HDO calculated for 1.36% glucose and icodextrin were similar (36.8 versus 39.7 ml/min; P = 0.3), whereas for other solutes, values obtained using icodextrin were consistently higher (P solutes is a reflection of their sieving. The increase in the MTAC of water and urea associated with an increase in convection is most likely due to increased mixing within the interstitium.

  6. Initial-Boundary Value Problem Solution of the Nonlinear Shallow-water Wave Equations

    Science.gov (United States)

    Kanoglu, U.; Aydin, B.

    2014-12-01

    The hodograph transformation solutions of the one-dimensional nonlinear shallow-water wave (NSW) equations are usually obtained through integral transform techniques such as Fourier-Bessel transforms. However, the original formulation of Carrier and Greenspan (1958 J Fluid Mech) and its variant Carrier et al. (2003 J Fluid Mech) involve evaluation integrals. Since elliptic integrals are highly singular as discussed in Carrier et al. (2003), this solution methodology requires either approximation of the associated integrands by smooth functions or selection of regular initial/boundary data. It should be noted that Kanoglu (2004 J Fluid Mech) partly resolves this issue by simplifying the resulting integrals in closed form. Here, the hodograph transform approach is coupled with the classical eigenfunction expansion method rather than integral transform techniques and a new analytical model for nonlinear long wave propagation over a plane beach is derived. This approach is based on the solution methodology used in Aydın & Kanoglu (2007 CMES-Comp Model Eng) for wind set-down relaxation problem. In contrast to classical initial- or boundary-value problem solutions, here, the NSW equations are formulated to yield an initial-boundary value problem (IBVP) solution. In general, initial wave profile with nonzero initial velocity distribution is assumed and the flow variables are given in the form of Fourier-Bessel series. The results reveal that the developed method allows accurate estimation of the spatial and temporal variation of the flow quantities, i.e., free-surface height and depth-averaged velocity, with much less computational effort compared to the integral transform techniques such as Carrier et al. (2003), Kanoglu (2004), Tinti & Tonini (2005 J Fluid Mech), and Kanoglu & Synolakis (2006 Phys Rev Lett). Acknowledgments: This work is funded by project ASTARTE- Assessment, STrategy And Risk Reduction for Tsunamis in Europe. Grant 603839, 7th FP (ENV.2013.6.4-3 ENV

  7. New era / new solutions: The role of alternative tariff structures in water supply projects.

    Science.gov (United States)

    Pinto, F Silva; Marques, R Cunha

    2017-12-01

    Water utilities face different challenges that may force them to seek prioritized objectives. When doing so, particular projects may have to be developed, being important to understand their impact on water tariffs, and thus, on customers. Such consequences may bear an increased relevance in cases stressed with, e.g., resource scarcity, poverty, and the need for infrastructure investments. The resulting cost and revenue variability demand a comprehensive study. If the first may require a stochastic modeling (in major cost components) in order to consider its inherent uncertainty, the second needs to be modeled following context-specific objectives set by the relevant stakeholders. The solutions achieved will likely promote distinct revenue sources, as well as diversified water tariff structures. A multi-objective optimization model (i.e., a Framework for Suitable Prices) is built to deal with those diversified requirements (e.g., stochastic energy costs, affordability, cost recovery, or administrative simplicity). The model is solved through achievement scalarizing functions with several weighting coefficients for a reference point, so as to provide a significant perception of possible revenue options (and their impact) to the decision makers. The proposed method is applied to a case study, Boa Vista Island in Cabo Verde, in which the background characteristics, namely water sources availability (e.g., the adoption of desalination technologies), economic development and other contextual factors were considered. The key role of tariff structure selection is displayed, instead of assuming it a priori, giving important insights regarding project feasibility. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Entropy of adsorption of mixed surfactants from solutions onto the air/water interface

    Science.gov (United States)

    Chen, L.-W.; Chen, J.-H.; Zhou, N.-F.

    1995-01-01

    The partial molar entropy change for mixed surfactant molecules adsorbed from solution at the air/water interface has been investigated by surface thermodynamics based upon the experimental surface tension isotherms at various temperatures. Results for different surfactant mixtures of sodium dodecyl sulfate and sodium tetradecyl sulfate, decylpyridinium chloride and sodium alkylsulfonates have shown that the partial molar entropy changes for adsorption of the mixed surfactants were generally negative and decreased with increasing adsorption to a minimum near the maximum adsorption and then increased abruptly. The entropy decrease can be explained by the adsorption-orientation of surfactant molecules in the adsorbed monolayer and the abrupt entropy increase at the maximum adsorption is possible due to the strong repulsion between the adsorbed molecules.

  9. Field-scale evaluation of water fluxes and manure solution leaching in feedlot pen soils.

    Science.gov (United States)

    García, Ana R; Maisonnave, Roberto; Massobrio, Marcelo J; Fabrizio de Iorio, Alicia R

    2012-01-01

    Accumulation of beef cattle manure on feedlot pen surfaces generates large amounts of dissolved solutes that can be mobilized by water fluxes, affecting surface and groundwater quality. Our objective was to examine the long-term impacts of a beef cattle feeding operation on water fluxes and manure leaching in feedlot pens located on sandy loam soils of the subhumid Sandy Pampa region in Argentina. Bulk density, gravimetric moisture content, and chloride concentration were quantified. Rain simulation trials were performed to estimate infiltration and runoff rates. Using chloride ion as a tracer, profile analysis techniques were applied to estimate the soil moisture flux and manure conservative chemical components leaching rates. An organic stratum was found over the surface of the pen soil, separated from the underlying soil by a highly compacted thin layer (the manure-soil interface). The soil beneath the organic layer showed greater bulk density in the A horizon than in the control soil and had greater moisture content. Greater concentrations of chloride were found as a consequence of the partial sealing of the manure-soil interface. Surface runoff was the dominant process in the feedlot pen soil, whereas infiltration was the main process in control soil. Soil moisture flux beneath pens decreased substantially after 15 yr of activity. The estimated minimum leaching rate of chloride was 13 times faster than the estimated soil moisture flux. This difference suggests that chloride ions are not exclusively transported by advective flow under our conditions but also by solute diffusion and preferential flow. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  10. A post Gurney quantum mechanical perspective on the electrolysis of water: ion neutralization in solution

    Science.gov (United States)

    Guo, Enyi; McKenzie, David R.

    2017-11-01

    Electron fluxes crossing the interface between a metallic conductor and an aqueous environment are important in many fields; hydrogen production, environmental scanning tunnelling microscopy, scanning electrochemical microscopy being some of them. Gurney (Gurney 1931 Proc. R. Soc. Lond. 134, 137 (doi:10.1098/rspa.1931.0187)) provided in 1931 a scheme for tunnelling during electrolysis and outlined conditions for it to occur. We measure the low-voltage current flows between gold electrodes in pure water and use the time-dependent behaviour at voltage switch-on and switch-off to evaluate the relative contribution to the steady current arising from tunnelling of electrons between the electrodes and ions in solution and from the neutralization of ions adsorbed onto the electrode surface. We ascribe the larger current contribution to quantum tunnelling of electrons to and from ions in solution near the electrodes. We refine Gurney's barrier scheme to include solvated electron states and quantify energy differences using updated information. We show that Gurney's conditions would prevent the current flow at low voltages we observe but outline how the ideas of Marcus (Marcus 1956 J. Chem. Phys. 24, 966-978 (doi:10.1063/1.1742723)) concerning solvation fluctuations enable the condition to be relaxed. We derive an average barrier tunnelling model and a multiple pathways tunnelling model and compare predictions with measurements of the steady-state current-voltage relation. The tunnelling barrier was found to be wide and low in agreement with other experimental studies. Applications as a biosensing mechanism are discussed that exploit the fast tunnelling pathways along molecules in solution.

  11. Deposition of Coating to Protect Waste Water Reservoir in Acidic Solution by Arc Thermal Spray Process

    Directory of Open Access Journals (Sweden)

    Han-Seung Lee

    2018-01-01

    Full Text Available The corrosion characteristics of 304 stainless steel (SS and titanium (Ti coatings deposited by the arc thermal spray process in pH 4 solution were assessed. The Ti-sprayed coating exhibits uniform, less porous, and adherent coating morphology compared to the SS-sprayed coating. The electrochemical study, that is, electrochemical impedance spectroscopy (EIS, revealed that as exposure periods to solution were increased, the polarization resistance (Rp decreased and the charge transfer resistance (Rct increased owing to corrosion of the metallic surface and simultaneously at the same time the deposition of oxide films/corrosion on the SS-sprayed surface, while Ti coating transformed unstable oxides into the stable phase. Potentiodynamic studies confirmed that both sprayed coatings exhibited passive tendency attributed due to the deposition of corrosion products on SS samples, whereas the Ti-sprayed sample formed passive oxide films. The Ti coating reduced the corrosion rate by more than six times compared to the SS coating after 312 h of exposure to sulfuric acid- (H2SO4- contaminated water solution, that is, pH 4. Scanning electron microscope (SEM results confirmed the uniform and globular morphology of the passive film on the Ti coating resulting in reduced corrosion. On the other hand, the corrosion products formed on SS-sprayed coating exhibit micropores with a net-like microstructure. X-ray diffraction (XRD revealed the presence of the composite oxide film on Ti-sprayed samples and lepidocrocite (γ-FeOOH on the SS-coated surface. The transformation of TiO and Ti3O into TiO2 (rutile and anatase and Ti3O5 after 312 h of exposure to H2SO4 acid reveals the improved corrosion resistance properties of Ti-sprayed coating.

  12. Water pumping system using solar photovoltaic induction motor; Sistema de bombeamento de agua com energia solar fotovoltaica utilizando motor de inducao trifasico

    Energy Technology Data Exchange (ETDEWEB)

    Andrade, Eduardo Henrique Pereira de; Bezerra, Luiz Daniel Santos; Antunes, Fernando Luiz Marcelo [Universidade Federal do Ceara (DEE/PPGEE/UFC), Fortaleza, CE (Brazil). Dept. de Engenharia Eletrica. Programa de Pos -Graduacao em Engenharia Eletrica; Borges Neto, Manuel Rangel [Centro Federal de Educacao Tecnologica de Petrolina (CEFET), PE (Brazil)

    2008-07-01

    One of the main difficulties to people who live in remote areas or isolated community and not grid connected, certainly is to access potable drink water. In the world, more than 6000 children dies everyday by some kind of illnesses associated to non-potable drink water. At state of Ceara, during the dry weather periods, remain water reservoir becomes practically a mud puddle, as a result, people and animals are forced to drink this inappropriate water. To minimize this consequences in this periods some water is distributed by tankers but, sometimes, even this water is not enough potable. Underground water is an alternative to mitigate this problem. The most common technique is the use of direct current (DC) pumps set supplied by solar photovoltaic systems. However, this kind of pump-set is relatively expensive and too hard to maintain. This paper brings an alternative lower expensive and sustainable to water pumping system, it uses a three phase induction machine coupled to an underwater centrifugal pump supplied by solar photovoltaic energy system. (author)

  13. Phytoextraction of cadmium by Ipomoea aquatica (water spinach) in hydroponic solution: effects of cadmium speciation.

    Science.gov (United States)

    Wang, Kai-Sung; Huang, Lung-Chiu; Lee, Hong-Shen; Chen, Pai-Ye; Chang, Shih-Hsien

    2008-06-01

    Phytoextraction is a promising technique to remediate heavy metals from contaminated wastewater. However, the interactions of multi-contaminants are not fully clear. This study employed cadmium, Triton X-100 (TX-100), and EDTA to investigate their interactions on phytotoxicity and Cd phytoextraction of Ipomoea aquatica (water spinach) in simulated wastewater. The Cd speciation was estimated by a chemical equilibrium model and MINEQL+. Statistic regression was applied to evaluate Cd speciation on Cd uptake in shoots and stems of I. aquatica. Results indicated that the root length was a more sensitive parameter than root weight and shoot weight. Root elongation was affected by Cd in the Cd-EDTA solution and TX-100 in the Cd-TX-100 solution. Both the root length and the root biomass were negatively correlated with the total soluble Cd ions. In contrast, Cd phytoextraction of I. aquatic was correlated with the aqueous Cd ions in the free and complex forms rather than in the chelating form. Additionally, the high Cd bioconcentration factors of I. aquatica (375-2227 l kg(-1) for roots, 45-144 l kg(-1) for shoots) imply that I. aquatica is a potential aquatic plant to remediate Cd-contaminated wastewater.

  14. Solubility of jarosite solid solutions precipitated from acid mine waters, Iron Mountain, California

    Science.gov (United States)

    Alpers, Charles N.; Nordstrom, D. Kirk; Ball, J.W.

    1989-01-01

    Because of the common occurrence of 15 to 25 mole percent hydronium substitution on the alkali site in jarosites, it is necessary to consider the hydronium content of jarosites in any attempt at rigorous evaluation of jarosite solubility or of the saturation state of natural waters with respect to jarosite. A Gibbs free energy of 3293.5±2.1 kJ mol-1 is recommended for a jarosite solid solution of composition K.77Na.03(H3O).20Fe3(SO4)2(OH)6. Solubility determinations for a wider range of natural and synthetic jarosite solid solutions will be necessary to quantify the binary and ternary mixing parameters in the (K-Na-H3O) system. In the absence of such studies, molar volume data for endmember minerals indicate that the K-H3O substitution in jarosite is probably closer to ideal mixing than either the Na-K or Na-H3O substitution.

  15. Energy-preserving H1-Galerkin schemes for shallow water wave equations with peakon solutions

    International Nuclear Information System (INIS)

    Miyatake, Yuto; Matsuo, Takayasu

    2012-01-01

    New energy-preserving Galerkin schemes for the Camassa–Holm and the Degasperis–Procesi equations which model shallow water waves are presented. The schemes can be implemented only with cheap H 1 elements, which is expected to be sufficient to catch the characteristic peakon solutions. The keys of the derivation are the Hamiltonian structures of the equations and an L 2 -projection technique newly employed in the present Letter to mimic the Hamiltonian structures in a discrete setting, so that the desired energy-preserving property rightly follows. Numerical examples confirm the effectiveness of the schemes. -- Highlights: ► Numerical integration of the Camassa–Holm and Degasperis–Procesi equation. ► New energy-preserving Galerkin schemes for these equations are proposed. ► They can be implemented only with P1 elements. ► They well capture the characteristic peakon solutions over long time. ► The keys are the Hamiltonian structures and L 2 -projection technique.

  16. Behavior of gellan in aqueous-salt solutions and oilfield saline water

    Directory of Open Access Journals (Sweden)

    Zhanar Nurakhmetova

    2015-09-01

    Full Text Available The influence of storage time and temperature on the behavior of low acyl gellan (LAG was studied by viscometry and 1H NMR spectroscopy without salt addition. The viscometric results revealed that the effectiveness of salts to enhance gelation of gellan changes in the following order: BaСl2>CaCl2»MgCl2>KCl>NaCl. The sol-gel and liquid-solid phase transitions of gellan solutions were observed upon addition of oilfield water containing 73 g L-1 of alkaline and alkaline earth metal ions. The effectiveness of salts to induce the separation of liquid and solid phases changes in the sequence: NaCl>KCl>MgCl2»CaCl2»BaСl2. The hydrodynamic behavior of 0.5 wt.% gellan solution injected into the sand pack model with high (20 Darcy and lower (2 Darcy permeability is useful to model the oil reservoirs in the process of enhanced oil recovery.

  17. Enzymatic hydrolysis of cellulose dissolved in N-methyl morpholine oxide/water solutions.

    Science.gov (United States)

    Ramakrishnan, S; Collier, J; Oyetunji, R; Stutts, B; Burnett, R

    2010-07-01

    In situ hydrolysis of cellulose (dissolving pulp) in N-methyl morpholine oxide (NMMO) solutions by commercially available Accellerase1000 is carried out. The yield of reducing sugars is followed as a function of time at three different temperatures and four different enzyme loadings to study the effect of system parameters on enzymatic hydrolysis. Initial results show that rates of hydrolysis of cellulose and yields of reducing sugars in the presence of NMMO-water is superior initially (ratio of initial reaction rates approximately 4) and comparable to that of regenerated cellulose (for times greater than 5h) when suspended in aqueous solutions. The usage of Accellerase1000 results predominantly in the formation of glucose with minimal amounts of cellobiose. This study proves the ability of cellulases to remain active in NMMO to carry out an in situ saccharification of cellulose thus eliminating the need to recover regenerated cellulose. Thus this work will form the basis for developing a continuous process for conversion of biomass to hydrogen, ethanol and other hydrocarbons. Copyright 2009 Elsevier Ltd. All rights reserved.

  18. Improved water and sodium absorption from oral rehydration solutions based on rice syrup in a rat model of osmotic diarrhea.

    Science.gov (United States)

    Wapnir, R A; Litov, R E; Zdanowicz, M M; Lifshitz, F

    1991-04-01

    Rice syrup solids, rice protein, and casein hydrolysate were added to experimental oral rehydration solutions in various combinations and tested in a rat intestinal perfusion system. Chronic osmotic diarrhea was induced in juvenile rats by supplying the cathartic agents, magnesium citrate and phenolphthalein, in their drinking water for 1 week. The experimental oral rehydration solutions were compared with standard oral rehydration solutions containing 20 gm/L or 30 gm/L of glucose and with each other to determine if there were significant differences in net water, sodium, or potassium absorption. An oral rehydration solution containing 30 gm/L of rice syrup solids had a net water absorption rate significantly higher than that of the standard 20 gm/L glucose-based oral rehydration solution (2.1 +/- 0.62 versus 1.5 +/- 0.48 microliters/[min x cm], p less than 0.05). Casein hydrolysate did not significantly affect net water absorption. However, combinations of 30 gm/L rice syrup solids and 5 gm/L casein hydrolysate significantly increased (p less than 0.05) net sodium and potassium absorption compared with the 20 gm/L glucose-based oral rehydration solution but not versus rice syrup solids alone. Oral rehydration solutions containing 30 gm/L rice syrup solids plus 5 gm/L rice protein, and 30 gm/L rice syrup solids plus 5 gm/L casein hydrolysate, had net water absorption rates significantly higher than the rate of a 30 gm/L glucose-based oral rehydration solution (2.5 +/- 0.36 and 2.4 +/- 0.38, respectively, versus 0.87 +/- 0.40 microliters/[min x cm], p less than 0.05). Rice protein and casein hydrolysate, however, did not significantly affect net water, sodium, or potassium absorption when added to rice protein glucose-based oral rehydration solutions. An inverse correlation between osmolality and net water absorption was observed (r = -0.653, p less than 0.02). The data suggest that substitution of rice syrup solids for glucose in oral rehydration solutions will

  19. Whole-body water flow stimulation to the lower limbs modulates excitability of primary motor cortical regions innervating the hands: a transcranial magnetic stimulation study.

    Directory of Open Access Journals (Sweden)

    Daisuke Sato

    Full Text Available Whole-body water immersion (WI has been reported to change sensorimotor integration. However, primary motor cortical excitability is not affected by low-intensity afferent input. Here we explored the effects of whole-body WI and water flow stimulation (WF on corticospinal excitability and intracortical circuits. Eight healthy subjects participated in this study. We measured the amplitude of motor-evoked potentials (MEPs produced by single transcranial magnetic stimulation (TMS pulses and examined conditioned MEP amplitudes by paired-pulse TMS. We evaluated short-interval intracortical inhibition (SICI and intracortical facilitation (ICF using the paired-TMS technique before and after 15-min intervention periods. Two interventions used were whole-body WI with water flow to the lower limbs (whole-body WF and whole-body WI without water flow to the lower limbs (whole-body WI. The experimental sequence included a baseline TMS assessment (T0, intervention for 15 min, a second TMS assessment immediately after intervention (T1, a 10 min resting period, a third TMS assessment (T2, a 10 min resting period, a fourth TMS assessment (T3, a 10 min resting period, and the final TMS assessment (T4. SICI and ICF were evaluated using a conditioning stimulus of 90% active motor threshold and a test stimulus adjusted to produce MEPs of approximately 1-1.2 mV, and were tested at intrastimulus intervals of 3 and 10 ms, respectively. Whole-body WF significantly increased MEP amplitude by single-pulse TMS and led to a decrease in SICI in the contralateral motor cortex at T1, T2 and T3. Whole-body WF also induced increased corticospinal excitability and decreased SICI. In contrast, whole-body WI did not change corticospinal excitability or intracortical circuits.

  20. Whole-body water flow stimulation to the lower limbs modulates excitability of primary motor cortical regions innervating the hands: a transcranial magnetic stimulation study.

    Science.gov (United States)

    Sato, Daisuke; Yamashiro, Koya; Onishi, Hideaki; Baba, Yasuhiro; Nakazawa, Sho; Shimoyama, Yoshimitsu; Maruyama, Atsuo

    2014-01-01

    Whole-body water immersion (WI) has been reported to change sensorimotor integration. However, primary motor cortical excitability is not affected by low-intensity afferent input. Here we explored the effects of whole-body WI and water flow stimulation (WF) on corticospinal excitability and intracortical circuits. Eight healthy subjects participated in this study. We measured the amplitude of motor-evoked potentials (MEPs) produced by single transcranial magnetic stimulation (TMS) pulses and examined conditioned MEP amplitudes by paired-pulse TMS. We evaluated short-interval intracortical inhibition (SICI) and intracortical facilitation (ICF) using the paired-TMS technique before and after 15-min intervention periods. Two interventions used were whole-body WI with water flow to the lower limbs (whole-body WF) and whole-body WI without water flow to the lower limbs (whole-body WI). The experimental sequence included a baseline TMS assessment (T0), intervention for 15 min, a second TMS assessment immediately after intervention (T1), a 10 min resting period, a third TMS assessment (T2), a 10 min resting period, a fourth TMS assessment (T3), a 10 min resting period, and the final TMS assessment (T4). SICI and ICF were evaluated using a conditioning stimulus of 90% active motor threshold and a test stimulus adjusted to produce MEPs of approximately 1-1.2 mV, and were tested at intrastimulus intervals of 3 and 10 ms, respectively. Whole-body WF significantly increased MEP amplitude by single-pulse TMS and led to a decrease in SICI in the contralateral motor cortex at T1, T2 and T3. Whole-body WF also induced increased corticospinal excitability and decreased SICI. In contrast, whole-body WI did not change corticospinal excitability or intracortical circuits.

  1. The SOLUTIONS project: challenges and responses for present and future emerging pollutants in land and water resources management.

    Science.gov (United States)

    Brack, Werner; Altenburger, Rolf; Schüürmann, Gerrit; Krauss, Martin; López Herráez, David; van Gils, Jos; Slobodnik, Jaroslav; Munthe, John; Gawlik, Bernd Manfred; van Wezel, Annemarie; Schriks, Merijn; Hollender, Juliane; Tollefsen, Knut Erik; Mekenyan, Ovanes; Dimitrov, Saby; Bunke, Dirk; Cousins, Ian; Posthuma, Leo; van den Brink, Paul J; López de Alda, Miren; Barceló, Damià; Faust, Michael; Kortenkamp, Andreas; Scrimshaw, Mark; Ignatova, Svetlana; Engelen, Guy; Massmann, Gudrun; Lemkine, Gregory; Teodorovic, Ivana; Walz, Karl-Heinz; Dulio, Valeria; Jonker, Michiel T O; Jäger, Felix; Chipman, Kevin; Falciani, Francesco; Liska, Igor; Rooke, David; Zhang, Xiaowei; Hollert, Henner; Vrana, Branislav; Hilscherova, Klara; Kramer, Kees; Neumann, Steffen; Hammerbacher, Ruth; Backhaus, Thomas; Mack, Juliane; Segner, Helmut; Escher, Beate; de Aragão Umbuzeiro, Gisela

    2015-01-15

    SOLUTIONS (2013 to 2018) is a European Union Seventh Framework Programme Project (EU-FP7). The project aims to deliver a conceptual framework to support the evidence-based development of environmental policies with regard to water quality. SOLUTIONS will develop the tools for the identification, prioritisation and assessment of those water contaminants that may pose a risk to ecosystems and human health. To this end, a new generation of chemical and effect-based monitoring tools is developed and integrated with a full set of exposure, effect and risk assessment models. SOLUTIONS attempts to address legacy, present and future contamination by integrating monitoring and modelling based approaches with scenarios on future developments in society, economy and technology and thus in contamination. The project follows a solutions-oriented approach by addressing major problems of water and chemicals management and by assessing abatement options. SOLUTIONS takes advantage of the access to the infrastructure necessary to investigate the large basins of the Danube and Rhine as well as relevant Mediterranean basins as case studies, and puts major efforts on stakeholder dialogue and support. Particularly, the EU Water Framework Directive (WFD) Common Implementation Strategy (CIS) working groups, International River Commissions, and water works associations are directly supported with consistent guidance for the early detection, identification, prioritisation, and abatement of chemicals in the water cycle. SOLUTIONS will give a specific emphasis on concepts and tools for the impact and risk assessment of complex mixtures of emerging pollutants, their metabolites and transformation products. Analytical and effect-based screening tools will be applied together with ecological assessment tools for the identification of toxicants and their impacts. The SOLUTIONS approach is expected to provide transparent and evidence-based candidates or River Basin Specific Pollutants in the case

  2. Fertilizer drawn forward osmosis process for sustainable water reuse to grow hydroponic lettuce using commercial nutrient solution

    KAUST Repository

    Chekli, Laura

    2017-03-10

    This study investigated the sustainable reuse of wastewater using fertilizer drawn forward osmosis (FDFO) process through osmotic dilution of commercial nutrient solution for hydroponics, a widely used technique for growing plants without soil. Results from the bench-scale experiments showed that the commercial hydroponic nutrient solution (i.e. solution containing water and essential nutrients) exhibited similar performance (i.e., water flux and reverse salt flux) to other inorganic draw solutions when treating synthetic wastewater. The use of hydroponic solution is highly advantageous since it provides all the required macro- (i.e., N, P and K) and micronutrients (i.e., Ca, Mg, S, Mn, B, Zn and Mo) in a single balanced solution and can therefore be used directly after dilution without the need to add any elements. After long-term operation (i.e. up to 75% water recovery), different physical cleaning methods were tested and results showed that hydraulic flushing can effectively restore up to 75% of the initial water flux while osmotic backwashing was able to restore the initial water flux by more than 95%; illustrating the low-fouling potential of the FDFO process. Pilot-scale studies demonstrated that the FDFO process is able to produce the required nutrient concentration and final water quality (i.e., pH and conductivity) suitable for hydroponic applications. Coupling FDFO with pressure assisted osmosis (PAO) in the later stages could help in saving operational costs (i.e., energy and membrane replacement costs). Finally, the test application of nutrient solution produced by the pilot FDFO process to hydroponic lettuce showed similar growth pattern as the control without any signs of nutrient deficiency.

  3. New design solutions for low-power energy production in water pipe systems

    Directory of Open Access Journals (Sweden)

    Helena M. Ramos

    2009-12-01

    Full Text Available This study is the result of ongoing research for a European Union 7th Framework Program Project regarding energy converters for very low heads, and aims to analyze optimization of new cost-effective hydraulic turbine designs for possible implementation in water supply systems (WSSs or in other pressurized water pipe infrastructures, such as irrigation, wastewater, or drainage systems. A new methodology is presented based on a theoretical, technical and economic analysis. Viability studies focused on small power values for different pipe systems were investigated. Detailed analyses of alternative typical volumetric energy converters were conducted on the basis of mathematical and physical fundamentals as well as computational fluid dynamics (CFD associated with the interaction between the flow conditions and the system operation. Important constraints (e.g., size, stability, efficiency, and continuous steady flow conditions can be identified and a search for alternative rotary volumetric converters is being conducted. As promising cost-effective solutions for the coming years, adapted rotor-dynamic turbomachines and non-conventional axial propeller devices were analyzed based on the basic principles of pumps operating as turbines, as well as through an extensive comparison between simulations and experimental tests.

  4. Comparison of acidic polymers for the removal of cobalt from water solutions by polymer assisted ultrafiltration

    Energy Technology Data Exchange (ETDEWEB)

    Dambies, Laurent, E-mail: chemjobs@netcourrir.com [Institute of Nuclear Chemistry and Technology, Dorodna 16, 03-195 Warsaw (Poland); Jaworska, Agnieszka, E-mail: a.jaworska@ichtj.waw.pl [Institute of Nuclear Chemistry and Technology, Dorodna 16, 03-195 Warsaw (Poland); Zakrzewska-Trznadel, Grazyna; Sartowska, Bozena [Institute of Nuclear Chemistry and Technology, Dorodna 16, 03-195 Warsaw (Poland)

    2010-06-15

    In this study, three sulfonated water-soluble polymers based on poly(vinyl alcohol) of different molecular weights (10,000, 50,000 and 100,000 Da) were prepared and tested against commercially available poly(acrylic acid) for the removal of cobalt using polymer assisted ultrafiltration. High rejection rates were obtained between pH 3 and 6 with sulfonated poly(vinyl alcohol) (PVA 10,000 and 50,000 Da) whereas poly(acrylic acid) (PAA) of similar molecular weights performed rather poorly in this pH range. Sulfonation improved significantly sorption capability of PVA. Sulfonated PVA 10,000 was the best complexing agent with rejection rate above 95% between pH 3 and 6. For unmodified PVA the rejection rate was only 30-45% at pH 6 and there was no rejection at pH 3 at all. PAA rejection rate was above 90% at pH 6 and only about 10% at pH 3. Large scale experiment in cross-flow, continuous apparatus conducted by using PVA-SO{sub 3}H 10,000 Da to remove {sup 60}Co radioisotope from water solutions showed excellent results demonstrating the potential of this polymer to purify acidic radioactive wastes containing cobalt radioisotopes.

  5. BIOSORPTION AND RECOVERY OF HEAVY METALS FROM AQUEOUS SOLUTIONS BY EICHHORNIA CRASSIPES (WATER HYACINTH ASH

    Directory of Open Access Journals (Sweden)

    Tariq Mahmood

    2010-04-01

    Full Text Available Heavy metal’s release without treatment poses a significant threat to the environment. Heavy metals are non-biodegradable and persistent. In the present study the ash of water hyacinth (Eichhornia crassipes, was used to remove six metals from aqueous solutions through biosorption. Results of batch and column experiments showed excellent adsorption capacity. Removal of lead, chromium, zinc, cadmium, copper, and nickel was 29.83, 1.263, 1.575, 3.323, 2.984 and 1.978 µgg-1, respectively. The biosorptive capacity was maximum with pH >8.00. Desorption in µgg-1 of ash for lead, chromium, zinc, cadmium, copper, and nickel was 18.10, 9.99, 11.99, 27.54, 21.09, and 3.71 respectively. Adsorption/desorption of these metals from ash showed the potential of this technology for recovery of metals for further usages. Hydrogen adsorption was also studied with a Sievert-type apparatus. Hydrogen adsorption experiments showed significant storage capacity of water hyacinth ash.

  6. Two-state model of excess electron relaxation and geminate recombination in water and aqueous solutions

    International Nuclear Information System (INIS)

    Fedorenko, S.G.

    2010-01-01

    Graphical abstract: After photo-induced ionization a free electron suffers a quick conversion to a solvated state, and then recombines with the parent atom or ion. However, high mobility and reactivity of a free electron can allow the electron to delocalize and recombine in the free state. The theory of two channel processes of geminate electron recombination is developed and applied to the experiment of three-pulse generation of excess electrons in water. - Abstract: After photo-induced ionization a free electron suffers a quick conversion to a solvated state, and then can recombine with the parent atom or ion. However, high mobility and reactivity of a free electron can allow the electron to delocalize and recombine in the free state. The theory of two channel processes of geminate electron recombination is developed here for the general type of the Markovian motion of reactants. A contact model is used for analytical solution of the problem of geminate recombination of neutral and charged reactants. The theory is applied to the experiment of three-pulse generation of excess electrons in water.

  7. Solution properties of targacanthin (water-soluble part of gum tragacanth exudate from Astragalus gossypinus).

    Science.gov (United States)

    Mohammadifar, Mohammad Amin; Musavi, Seyed Mohammad; Kiumarsi, Amir; Williams, Peter A

    2006-02-28

    Solution properties of tragacanthin (the water-soluble part of gum tragacanth) were studied by gel permeation chromatography (GPC) combined with multi-angle light scattering and viscometry at 25 degrees C. Photon correlation spectroscopy was used to determine the hydrodynamic radius. Ultrasonic degradation was applied to obtain biopolymer fractions of different molecular weights. The dependence of intrinsic viscosity [eta] and radius of gyration (s2)z(1/2) on weight average molecular mass M(w) for this biopolymer were found to be [eta] = 9.077 x 10(-5) M(w)(0.87) (dL g(-1)) and (s2)z(1/2) in the range of M(w) from 1.8 x 10(5) to 1.6 x 10(6). The conformational parameters of tragacanthin were calculated to be 1111 nm for molar mass per unit contour length (M(L)), 26 nm for persistence length (q) and 1.87 ratio of R(g)/R(h). It was found that the Smidsrød parameter B, the empirical stiffness parameter was 0.013, which is lower than that of several polysaccharides indicating the stiff backbone for tragacanthin. The rheological behavior of aqueous solutions of gum tragacanth and its insoluble and soluble fractions (bassorin and tragacanthin, respectively) were studied. For concentrations equal to 1%, at 25 degrees C and in the absence of salt, bassorin solution showed the highest viscosity and shear thinning behaviour. Power law and Williamson models were used to describe the rheological behaviour of bassorin and tragacanthin, respectively. Oscillatory shear experiments showed a gel like structure for the bassorin but for tragacanthin the oscillatory data were as would be expected for semi-dilute to concentrated solution of entangled, random coil polymers. NaCl changed the steady and oscillatory rheological properties of both fractions and in this way the final viscosity of bassorin was even less than tragacanthin. The calculated activation energy for bassorin and tragacanthin indicated a more rapid decrease in viscosity with temperature for tragacanthin. The plot of

  8. Water movement through plant roots - exact solutions of the water flow equation in roots with linear or exponential piecewise hydraulic properties

    Science.gov (United States)

    Meunier, Félicien; Couvreur, Valentin; Draye, Xavier; Zarebanadkouki, Mohsen; Vanderborght, Jan; Javaux, Mathieu

    2017-12-01

    In 1978, Landsberg and Fowkes presented a solution of the water flow equation inside a root with uniform hydraulic properties. These properties are root radial conductivity and axial conductance, which control, respectively, the radial water flow between the root surface and xylem and the axial flow within the xylem. From the solution for the xylem water potential, functions that describe the radial and axial flow along the root axis were derived. These solutions can also be used to derive root macroscopic parameters that are potential input parameters of hydrological and crop models. In this paper, novel analytical solutions of the water flow equation are developed for roots whose hydraulic properties vary along their axis, which is the case for most plants. We derived solutions for single roots with linear or exponential variations of hydraulic properties with distance to root tip. These solutions were subsequently combined to construct single roots with complex hydraulic property profiles. The analytical solutions allow one to verify numerical solutions and to get a generalization of the hydric behaviour with the main influencing parameters of the solutions. The resulting flow distributions in heterogeneous roots differed from those in uniform roots and simulations led to more regular, less abrupt variations of xylem suction or radial flux along root axes. The model could successfully be applied to maize effective root conductance measurements to derive radial and axial hydraulic properties. We also show that very contrasted root water uptake patterns arise when using either uniform or heterogeneous root hydraulic properties in a soil-root model. The optimal root radius that maximizes water uptake under a carbon cost constraint was also studied. The optimal radius was shown to be highly dependent on the root hydraulic properties and close to observed properties in maize roots. We finally used the obtained functions for evaluating the impact of root maturation

  9. Water movement through plant roots – exact solutions of the water flow equation in roots with linear or exponential piecewise hydraulic properties

    Directory of Open Access Journals (Sweden)

    F. Meunier

    2017-12-01

    Full Text Available In 1978, Landsberg and Fowkes presented a solution of the water flow equation inside a root with uniform hydraulic properties. These properties are root radial conductivity and axial conductance, which control, respectively, the radial water flow between the root surface and xylem and the axial flow within the xylem. From the solution for the xylem water potential, functions that describe the radial and axial flow along the root axis were derived. These solutions can also be used to derive root macroscopic parameters that are potential input parameters of hydrological and crop models. In this paper, novel analytical solutions of the water flow equation are developed for roots whose hydraulic properties vary along their axis, which is the case for most plants. We derived solutions for single roots with linear or exponential variations of hydraulic properties with distance to root tip. These solutions were subsequently combined to construct single roots with complex hydraulic property profiles. The analytical solutions allow one to verify numerical solutions and to get a generalization of the hydric behaviour with the main influencing parameters of the solutions. The resulting flow distributions in heterogeneous roots differed from those in uniform roots and simulations led to more regular, less abrupt variations of xylem suction or radial flux along root axes. The model could successfully be applied to maize effective root conductance measurements to derive radial and axial hydraulic properties. We also show that very contrasted root water uptake patterns arise when using either uniform or heterogeneous root hydraulic properties in a soil–root model. The optimal root radius that maximizes water uptake under a carbon cost constraint was also studied. The optimal radius was shown to be highly dependent on the root hydraulic properties and close to observed properties in maize roots. We finally used the obtained functions for evaluating the impact

  10. Development of nanocomposites polyamide66/ bentonite clay membranes obtained by solution for water-oil separation

    International Nuclear Information System (INIS)

    Medeiros, Keila Machado de

    2010-01-01

    Microporous membranes were obtained from nanocomposites polyamide66 and regional bentonite clay, through the technique of immersion precipitation. The nanocomposites were obtained by solution with a pre-established reaction time. The clay was treated with quaternary ammonium salt (Cetremide®) in order to make it organophilic. Untreated and treated clay were characterized by X-ray fluorescence (XRF) spectroscopy, Fourier transform infrared (FTIR), X-ray diffraction (XRD) and thermogravimetry (TG), which confirmed the insertion of the Cetremide® salt in the layers of clay and their thermal stability. While the membranes were characterized by XRD, TG, differential scanning calorimetry (DSC), scanning electron microscopy (SEM) and flow measurements. The results of XRD, TG and DSC confirmed the thermal stability and morphological structure with intercalated/partially exfoliated lamellae of clay in the polymer matrix. By SEM, it was revealed an asymmetric morphology consisting of a skin layer and a porous sublayer. The higher clay content in the membrane give the lower film thickness. This influencing directly the flow measurements of the membranes produced from the nanocomposites. In general, the initial flow with distilled water through the membranes decrease and stabilise after 60 min, this due to a compression or swelling occurred in the membranes. In tests of water-oil separation it was found that the relationship J/J0 tends to be greater when using emulsions with lower concentration. The water-oil separation tests at concentrations of 300 and 500 ppm for all membranes showed a significant reduction in oil concentration in the permeate, thus showing that these membranes have potential for this application. (author)

  11. Solute transport in coupled inland-coastal water systems. General conceptualisation and application to Forsmark

    International Nuclear Information System (INIS)

    Jarsjoe, Jerker; Destouni, Georgia; Persson, Klas; Prieto, Carmen

    2007-12-01

    We formulate a general theoretical conceptualisation of solute transport from inland sources to downstream recipients, considering main recipient load contributions from all different nutrient and pollutant sources that may exist within any catchment. Since the conceptualisation is model independent, its main hydrological factors and mass delivery factors can be quantified on the basis of inputs to and outputs from any considered analytical or numerical model. Some of the conceptually considered source contribution and transport pathway combinations are however commonly neglected in catchment-scale solute transport and attenuation modelling, in particular those related to subsurface sources, diffuse sources at the land surface and direct groundwater transport into the recipient. The conceptual framework provides a possible tool for clarification of underlying and often implicit model assumptions, which can be useful for e.g. inter-model comparisons. In order to further clarify and explain research questions that may be of particular importance for transport pathways from deep groundwater surrounding a repository, we concretise and interpret some selected transport scenarios for model conditions in the Forsmark area. Possible uncertainties in coastal discharge predictions, related to uncertain spatial variation of evapotranspiration within the catchment, were shown to be small for the relatively large, focused surface water discharges from land to sea, because local differences were averaged out along the length of the main water flow paths. In contrast, local flux values within the diffuse groundwater flow field from land to sea are more uncertain, although estimates of mean values and total sums of submarine groundwater discharge (SGD) along some considerable coastline length may be robust. The present results show that 80% to 90% of the total coastal discharge of Forsmark occurred through focused flows in visible streams, whereas the remaining 10% to 20% was

  12. Solution deposited and modified iron oxide for enhanced solar water splitting

    Science.gov (United States)

    Abel, Anthony J.

    Growing worldwide energy demand coupled with an increasing awareness of anthropogenic climate change has driven research into carbon-neutral and solar-derived energy sources. One attractive strategy is the storage of solar energy in the bonds of H2 formed by photoelectrochemical (PEC) water splitting. Hematite, an iron oxide, has been widely investigated as a candidate material for PEC water splitting due to its stability, non-toxicity, earth abundance and consequent low cost, and a theoretical 15% solar-to-hydrogen conversion efficiency. However, poor electrical properties and slow rates of the water oxidation reaction have limited its potential as an economical water splitting catalyst. Additionally, the most efficient hematite-based devices are fabricated via expensive, vacuum-phase techniques, limiting scalability to broad integration into the energy supply. In this thesis, I develop a new, solution-based deposition method for high quality, planar hematite thin films using successive ionic layer adsorption and reaction (SILAR). The constant geometry and tight control over layer thickness possible with SILAR makes these films ideal model systems to understand the two key steps of PEC water oxidation: charge separation and interfacial hole transfer. In Chapter 3, I report on facile annealing treatments to dope hematite with Ti and Sn, and I show that these impurity atoms at the hematite/electrolyte interface increase hole transfer efficiency from nearly 0 to above 60%. However, charge separation remains below 15% with these dopants incorporated via solid state diffusion, mainly due to low hole mobility. To overcome this associated small transport length, extremely thin hematite coatings were deposited on Sb:SnO2 monolayer inverse opal scaffolds. With this modified substrate, photocurrent increased proportionately to the surface area of the scaffold. While Chapter 3 discusses incorporation of dopants via solid state diffusion, Chapter 4 examines methods to

  13. A model for radiolysis of water and aqueous solutions of H2, H2O2 and O2

    International Nuclear Information System (INIS)

    Ershov, B.G.; Gordeev, A.V.

    2008-01-01

    Kinetic model for the radiolysis of pure water describing the formation of H 2 , H 2 O 2 and O 2 and the radiation chemical transformations of aqueous solutions containing these compounds over a broad range of concentrations, pH, absorbed doses and dose rates is proposed and substantiated. The model includes a set of chemical reactions with optimized rate constants and the radiation chemical yields of radiolysis products. The model applicability to the description of the whole set of data on the radiation chemical transformations of water and aqueous solutions of H 2 , H 2 O 2 and O 2 is demonstrated

  14. Solute transport in coupled inland-coastal water systems. General conceptualisation and application to Forsmark

    Energy Technology Data Exchange (ETDEWEB)

    Jarsjoe, Jerker; Destouni, Georgia; Persson, Klas; Prieto, Carmen (Dept. of Physical Geography, Quaternary Geology, Stockholm Univ., Stockholm (Sweden))

    2007-12-15

    We formulate a general theoretical conceptualisation of solute transport from inland sources to downstream recipients, considering main recipient load contributions from all different nutrient and pollutant sources that may exist within any catchment. Since the conceptualisation is model independent, its main hydrological factors and mass delivery factors can be quantified on the basis of inputs to and outputs from any considered analytical or numerical model. Some of the conceptually considered source contribution and transport pathway combinations are however commonly neglected in catchment-scale solute transport and attenuation modelling, in particular those related to subsurface sources, diffuse sources at the land surface and direct groundwater transport into the recipient. The conceptual framework provides a possible tool for clarification of underlying and often implicit model assumptions, which can be useful for e.g. inter-model comparisons. In order to further clarify and explain research questions that may be of particular importance for transport pathways from deep groundwater surrounding a repository, we concretise and interpret some selected transport scenarios for model conditions in the Forsmark area. Possible uncertainties in coastal discharge predictions, related to uncertain spatial variation of evapotranspiration within the catchment, were shown to be small for the relatively large, focused surface water discharges from land to sea, because local differences were averaged out along the length of the main water flow paths. In contrast, local flux values within the diffuse groundwater flow field from land to sea are more uncertain, although estimates of mean values and total sums of submarine groundwater discharge (SGD) along some considerable coastline length may be robust. The present results show that 80% to 90% of the total coastal discharge of Forsmark occurred through focused flows in visible streams, whereas the remaining 10% to 20% was

  15. Concentration Dependences of the Surface Tension and Density of Solutions of Acetone-Ethanol-Water Systems at 293 K

    Science.gov (United States)

    Dadashev, R. Kh.; Dzhambulatov, R. S.; Mezhidov, V. Kh.; Elimkhanov, D. Z.

    2018-05-01

    Concentration dependences of the surface tension and density of solutions of three-component acetone-ethanol-water systems and the bounding binary systems at 273 K are studied. The molar volume, adsorption, and composition of surface layers are calculated. Experimental data and calculations show that three-component solutions are close to ideal ones. The surface tensions of these solutions are calculated using semi-empirical and theoretical equations. Theoretical equations qualitatively convey the concentration dependence of surface tension. A semi-empirical method based on the Köhler equation allows us to predict the concentration dependence of surface tension within the experimental error.

  16. Analytic solution to verify code predictions of two-phase flow in a boiling water reactor core channel

    International Nuclear Information System (INIS)

    Chen, K.F.; Olson, C.A.

    1983-01-01

    One reliable method that can be used to verify the solution scheme of a computer code is to compare the code prediction to a simplified problem for which an analytic solution can be derived. An analytic solution for the axial pressure drop as a function of the flow was obtained for the simplified problem of homogeneous equilibrium two-phase flow in a vertical, heated channel with a cosine axial heat flux shape. This analytic solution was then used to verify the predictions of the CONDOR computer code, which is used to evaluate the thermal-hydraulic performance of boiling water reactors. The results show excellent agreement between the analytic solution and CONDOR prediction

  17. Photoelectrochemical water splitting with mesoporous hematite prepared by a solution-based colloidal approach.

    Science.gov (United States)

    Sivula, Kevin; Zboril, Radek; Le Formal, Florian; Robert, Rosa; Weidenkaff, Anke; Tucek, Jiri; Frydrych, Jiri; Grätzel, Michael

    2010-06-02

    Sustainable hydrogen production through photoelectrochemical water splitting using hematite (alpha-Fe(2)O(3)) is a promising approach for the chemical storage of solar energy, but is complicated by the material's nonoptimal optoelectronic properties. Nanostructuring approaches have been shown to increase the performance of hematite, but the ideal nanostructure giving high efficiencies for all absorbed light wavelengths remains elusive. Here, we report for the first time mesoporous hematite photoelectodes prepared by a solution-based colloidal method which yield water-splitting photocurrents of 0.56 mA cm(-2) under standard conditions (AM 1.5G 100 mW cm(-2), 1.23 V vs reversible hydrogen electrode, RHE) and over 1.0 mA cm(-2) before the dark current onset (1.55 V vs RHE). The sintering temperature is found to increase the average particle size, and have a drastic effect on the photoactivity. X-ray photoelectron spectroscopy and magnetic measurements using a SQUID magnetometer link this effect to the diffusion and incorporation of dopant atoms from the transparent conducting substrate. In addition, examining the optical properties of the films reveals a considerable change in the absorption coefficient and onset properties, critical aspects for hematite as a solar energy converter, as a function of the sintering temperature. A detailed investigation into hematite's crystal structure using powder X-ray diffraction with Rietveld refinement to account for these effects correlates an increase in a C(3v)-type crystal lattice distortion to the improved optical properties.

  18. Plugging solution

    Energy Technology Data Exchange (ETDEWEB)

    Sharipov, A U; Yangirov, I Z

    1982-01-01

    A clay-powder, cement, and water-base plugging solution is proposed having reduced solution viscosity characteristics while maintaining tensile strength in cement stone. This solution utilizes silver graphite and its ingredients, by mass weight, are as follows: cement 51.2-54.3%; claypowder 6.06-9.1%; silver graphite 0.24-0.33%; with water making up the remainder.

  19. Highly water soluble nanoparticles as a draw solute in forward osmosis for the treatment of radioactive liquid waste

    International Nuclear Information System (INIS)

    Yang, Heeman; Choi, Hye Min; Jang, Sungchan; Seo, Bumkyoung; Lee, Kune Woo; Moon, Jei Kwon

    2014-01-01

    . In this study, we introduced highly water-soluble hyperbranched caroboxylated polyglycerol-coated magnetic nanoparticles (CPG-MNPs). It is known that the highly branched, globular architecture of PG significantly increase solubility compared to linear polymer and they are eco-friendly. The CPG-MNPs showed no aggregate of particles in water even after placing external magnet, and exhibited a high water flux in FO process. The CPG-MNPs are, therefore, potentially useful as a draw solute in FO processes. The operation of nuclear pressurized water reactors (PWRs) results in numerous radioactive waste streams which vary in radioactivity content. Most PWR stations have experienced leakages of boric acid into liquid radioactive waste systems. These wastes contain about 0.3∼0.8 wt% of boric acid. It is known that reverse osmosis (RO) membrane can eliminate boron at high pH and boron of 40∼90% can be removed by RO membrane in pH condition. RO uses hydraulic pressure to oppose, and exceed, the osmotic pressure of an aqueous feed solution containing boric acid. Forward osmosis (FO), a low energy technique based on membrane technologies, has recently garnered attention for its utility in wastewater treatment and desalination applications. In the FO process, water flows across a semi-permeable membrane from a solution with a low osmotic pressure (the feed solution) to a solution with a high osmotic pressure (the draw solution). The driving force in FO processes is provided by the osmotic gradient between the two solutions. Low energy costs and low degrees of membrane fouling are two of the advantages conveyed by FO processes over other processes, such as reverse osmosis processes that rely on a hydraulic pressure driving force. However, the challenges of FO still lie in the fabrication of eligible FO membranes and the readily separable draw solutes of high osmotic pressures. Superparamagnetic Fe3O4 nanoparticles can be separated from water by an external magnet field

  20. Highly water soluble nanoparticles as a draw solute in forward osmosis for the treatment of radioactive liquid waste

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Heeman; Choi, Hye Min; Jang, Sungchan; Seo, Bumkyoung; Lee, Kune Woo; Moon, Jei Kwon [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2014-05-15

    . In this study, we introduced highly water-soluble hyperbranched caroboxylated polyglycerol-coated magnetic nanoparticles (CPG-MNPs). It is known that the highly branched, globular architecture of PG significantly increase solubility compared to linear polymer and they are eco-friendly. The CPG-MNPs showed no aggregate of particles in water even after placing external magnet, and exhibited a high water flux in FO process. The CPG-MNPs are, therefore, potentially useful as a draw solute in FO processes. The operation of nuclear pressurized water reactors (PWRs) results in numerous radioactive waste streams which vary in radioactivity content. Most PWR stations have experienced leakages of boric acid into liquid radioactive waste systems. These wastes contain about 0.3∼0.8 wt% of boric acid. It is known that reverse osmosis (RO) membrane can eliminate boron at high pH and boron of 40∼90% can be removed by RO membrane in pH condition. RO uses hydraulic pressure to oppose, and exceed, the osmotic pressure of an aqueous feed solution containing boric acid. Forward osmosis (FO), a low energy technique based on membrane technologies, has recently garnered attention for its utility in wastewater treatment and desalination applications. In the FO process, water flows across a semi-permeable membrane from a solution with a low osmotic pressure (the feed solution) to a solution with a high osmotic pressure (the draw solution). The driving force in FO processes is provided by the osmotic gradient between the two solutions. Low energy costs and low degrees of membrane fouling are two of the advantages conveyed by FO processes over other processes, such as reverse osmosis processes that rely on a hydraulic pressure driving force. However, the challenges of FO still lie in the fabrication of eligible FO membranes and the readily separable draw solutes of high osmotic pressures. Superparamagnetic Fe3O4 nanoparticles can be separated from water by an external magnet field

  1. Field-scale water flow and solute transport : SWAP model concepts, parameter estimation and case studies = [Waterstroming en transport van opgeloste stoffen op veldschaal

    NARCIS (Netherlands)

    Dam, van J.C.

    2000-01-01

    Water flow and solute transport in top soils are important elements in many environmental studies. The agro- and ecohydrological model SWAP (Soil-Water-Plant-Atmosphere) has been developed to simulate simultaneously water flow, solute transport, heat flow and crop growth at field scale

  2. Analysis of water sorption isotherms of amorphous food materials by solution thermodynamics with relevance to glass transition: evaluation of plasticizing effect of water by the thermodynamic parameters.

    Science.gov (United States)

    Shimazaki, Eriko; Tashiro, Akiko; Kumagai, Hitomi; Kumagai, Hitoshi

    2017-04-01

    Relation between the thermodynamic parameters obtained from water sorption isotherms and the degree of reduction in the glass transition temperature (T g ), accompanied by water sorption, was quantitatively studied. Two well-known glassy food materials namely, wheat gluten and maltodextrin were used as samples. The difference between the chemical potential of water in a solution and that of pure water ([Formula: see text]), the difference between the chemical potential of solid in a solution and that of a pure solid ([Formula: see text]), and the change in the integral Gibbs free energy ([Formula: see text]) were obtained by analyzing the water sorption isotherms using solution thermodynamics. The parameter [Formula: see text] correlated well with ΔT g (≡T g  - T g0 ; where T g0 is the glass transition temperature of dry material), which had been taken to be an index of plasticizing effect. This indicates that plasticizing effect of water on foods can be evaluated through the parameter [Formula: see text].

  3. Removal of Lanthanum (III) From Aqueous Solution Using Non-Living Water Hyacinth Roots

    International Nuclear Information System (INIS)

    Aly, A.; Amer, H.A.; Shawky, S.; Shawky, S.; Kandil, A.T.

    2013-01-01

    Removal of lanthanum (III) from aqueous solution using dried roots of water hyacinth (Eichhornia crassipes) has been investigated. The roots have been characterized by determining the ash percentage, the ph of the slurry, the elemental composition, the thermal gravimetric analysis, the surface area, the pore size, the zeta potential and ph of zero point charge. A surface area of 128 m 2 /g has been found and the micropore structure of the roots has been confirmed. Zeta potential and ph of zero point charge of the roots surfaces showed that they are positively charged within the ph range from 2 to 7.5. Sorption is rapid and depends on ph, weight of roots, concentration of lanthanum (III) and ionic strength. The sorption of lanthanum (III) was confirmed by scanning electron microscope, energy dispersive spectroscopy and the release of Ca +2 , Mg +2 and K +1 after sorption of lanthanum (III) have been indicated an ion exchange mechanism. Fourier transform infrared spectra indicated surface complexation mechanism, and sorption isotherms and kinetics were discussed. The roots were tested for removal of radioactive lanthanum ( 140 La) from simulated radioactive waste. Accepted June 2013.

  4. Implementation of the national desalination and water purification technology roadmap : structuring and directing the development of water supply solutions.

    Energy Technology Data Exchange (ETDEWEB)

    Price, Kevin M.; Dorsey, Zachary; Miller, G. Wade; Brady, Patrick Vane; Mulligan, Conrad; Rayburn, Chris

    2006-06-01

    In the United States, economic growth increasingly requires that greater volumes of freshwater be made available for new users, yet supplies of freshwater are already allocated to existing users. Currently, water for new users is made available through re-allocation of xisting water supplies-for example, by cities purchasing agricultural water rights. Water may also be made available through conservation efforts and, in some locales, through the development of ''new'' water from non-traditional sources such as the oceans, deep aquifer rackish groundwater, and water reuse.

  5. Summary: High Temperature Downhole Motor

    Energy Technology Data Exchange (ETDEWEB)

    Raymond, David W. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2017-10-01

    Directional drilling can be used to enable multi-lateral completions from a single well pad to improve well productivity and decrease environmental impact. Downhole rotation is typically developed with a motor in the Bottom Hole Assembly (BHA) that develops drilling power (speed and torque) necessary to drive rock reduction mechanisms (i.e., the bit) apart from the rotation developed by the surface rig. Historically, wellbore deviation has been introduced by a “bent-sub,” located in the BHA, that introduces a small angular deviation, typically less than 3 degrees, to allow the bit to drill off-axis with orientation of the BHA controlled at the surface. The development of a high temperature downhole motor would allow reliable use of bent subs for geothermal directional drilling. Sandia National Laboratories is pursuing the development of a high temperature motor that will operate on either drilling fluid (water-based mud) or compressed air to enable drilling high temperature, high strength, fractured rock. The project consists of designing a power section based upon geothermal drilling requirements; modeling and analysis of potential solutions; and design, development and testing of prototype hardware to validate the concept. Drilling costs contribute substantially to geothermal electricity production costs. The present development will result in more reliable access to deep, hot geothermal resources and allow preferential wellbore trajectories to be achieved. This will enable development of geothermal wells with multi-lateral completions resulting in improved geothermal resource recovery, decreased environmental impact and enhanced well construction economics.

  6. Proposing buffer zones and simple technical solutions for safeguarding river water quality and public health

    Science.gov (United States)

    Podimata, M. V.; Bekri, E. S.; Yannopoulos, P. C.

    2012-04-01

    Alfeios River Basin (ARB) constitutes one of the major hydrologic basins (≈3650km2) of Peloponnisos peninsula in Southern Greece. It is drained by Alfeios River and its tributaries, such as Lousios, Ladhon, Erymanthos, Kladheos, Selinous etc. The present manuscript takes a closer look at the importance of tributary basins and focuses on Erymanthos sub-basin that covers about 360 km2. Erymanthos River springs from Erymanthos Mountain that reaches altitudes of 2200 m and discharges 10 m3/sec, approximately, during the winter period, presenting a sound decrease from half to about an order of magnitude during summertime. Two factors stand out as reasons to select Erymanthos sub-basin as a case study. First, the sub-basin presents a significant variety of ecosystems and comprises a very important river system, since Erymanthos Tributary satisfies, among other uses, drinking water supply for a great majority of citizens in the region. Second, authors' experience of the study area in Research Program Pythagoras II, funded by the European Social Fund (ESF) and the Operational Program for Educational and Vocational Training II (EPEAEK II) of Greece, offers a basis for better understanding of the real problems in the area. Erymanthos watershed, in fact, faces a lot of pressures, in several levels, provoked by human activities and Erymanthos Tributary is vulnerable to pollution. Recognizing the importance of clean water for healthy people, a developing economy, and a sustainable environment, the challenge of the present paper is elaborating human-induced pressures in the study area, analyzing their effects, estimating pollution factors and proposing integrated solutions/tools and a number of methodologies/initiatives used to overcome the problem of contaminating water supply in a catchment that lacks of wastewater treatment and disposal systems. The preservation of a good ecological status in Erymanthos River is not only a necessity for achieving the goals of EU Water

  7. Thermodynamic analysis of sol-gel transition of gelatin in terms of water activity in various solutions.

    Science.gov (United States)

    Miyawaki, Osato; Omote, Chiaki; Matsuhira, Keiko

    2015-12-01

    Sol-gel transition of gelatin was analyzed as a multisite stoichiometric reaction of a gelatin molecule with water and solute molecules. The equilibrium sol-gel transition temperature, Tt , was estimated from the average of gelation and melting temperature measured by differential scanning calorimetry. From Tt and the melting enthalpy, ΔHsol , the equilibrium sol-to-gel ratio was estimated by the van't Hoff equation. The reciprocal form of the Wyman-Tanford equation, which describes the sol-to-gel ratio as a function of water activity, was successfully applied to obtain a good linear relationship. From this analysis, the role of water activity on the sol-gel transition of gelatin was clearly explained and the contributions of hydration and solute binding to gelatin molecules were separately discussed in sol-gel transition. The general solution for the free energy for gel-stabilization in various solutions was obtained as a simple function of solute concentration. © 2015 Wiley Periodicals, Inc.

  8. Formulation and make-up of simulated concentrated water, high ionic content aqueous solution

    International Nuclear Information System (INIS)

    Gdowski, G.

    1997-01-01

    This procedure describes the formulation and make-up of Simulated Concentrated Water (SCW), a high-ionic-content water to be used for Activity E-20-50 Long-Term Corrosion Studies. This water has an ionic content which is nominally a factor of a thousand higher than that of representative waters at or near Yucca Mountain. Representative waters were chosen as J-13 well water [Harrar, 1990] and perched water at Yucca Mountain [Glassley, 1996]. J-13 well water is obtained from ground water that is in contact with the Topopah Spring tuff, which is the repository horizon rock. The perched water is located in the Topopah Spring tuff, but below the repository horizon and above the water table. A nominal thousand times higher ionic content was chosen to simulate the water that would result from the wetting of salts which have been previously deposited on a container surface

  9. Formulation and make-up of simulate dilute water, low ionic content aqueous solution

    International Nuclear Information System (INIS)

    Gdowski, G.

    1997-01-01

    This procedure describes the formulation and make-up of Simulated Dilute Water (SOW), a low-ionic-content water to be used for Activity E-20-50, Long-Term Corrosion Studies. This water has an ionic content which is nominally a factor of ten higher than that of representative waters at or near Yucca Mountain. Representative waters were chosen as J-13 well water [Harrar, 1990] and perched water at Yucca Mountain [Glassley, 1996]. J-13 well water is obtained from ground water that is in contact with the Topopah Spring tuff, which is the repository horizon rock. The perched water is located in the Topopah Spring tuff, but below the repository horizon and above the water table. A nominal times ten higher ionic content was chosen to simulate the effect of ionic concentrating due to elevated temperature water flowing through fractures where salts and minerals have been deposited due to evaporation and boiling

  10. Retro-Diels-Alder reaction in aqueous solution : Toward a better understanding of organic reactivity in water

    NARCIS (Netherlands)

    Wijnen, J.W.; Engberts, Jan B.F.N.

    1997-01-01

    The retro-Diels-Alder (RDA) reaction of anthracenedione 1a proceeds considerably faster in aqueous solutions than in organic solvents. Addition of organic solvents to water retards the reaction, whereas glucose induces a modest acceleration. SDS micelles induce a considerable retardation, but even

  11. A mass conservative numerical solution of vertical water flow and mass transport equations in unsaturated porous media

    International Nuclear Information System (INIS)

    Lim, S.C.; Lee, K.J.

    1993-01-01

    The Galerkin finite element method is used to solve the problem of one-dimensional, vertical flow of water and mass transport of conservative-nonconservative solutes in unsaturated porous media. Numerical approximations based on different forms of the governing equation, although they are equivalent in continuous forms, can result in remarkably different solutions in an unsaturated flow problem. Solutions given by a simple Galerkin method based on the h-based Richards equation yield a large mass balance error and an underestimation of the infiltration depth. With the employment of the ROMV (restoration of main variable) concept in the discretization step, the mass conservative numerical solution algorithm for water flow has been derived. The resulting computational schemes for water flow and mass transport are applied to sandy soil. The ROMV method shows good mass conservation in water flow analysis, whereas it seems to have a minor effect on mass transport. However, it may relax the time-step size restriction and so ensure an improved calculation output. (author)

  12. Correlation between the solubility of aromatic hydrocarbons in water and micellar solutions, with their normal boiling points

    International Nuclear Information System (INIS)

    Almgren, M.; Grieser, F.; Powell, J.R.; Thomas, J.K.

    1979-01-01

    A linear correlation between the logarithm of the solubility in water of aromatic hydrocarbons and their normal boiling points is shown. Similarly, the logarithm of the distribution ratio of aromatic hydrocarbons in aqueous micellar solution is shown to be linearly related to the boiling points of the hydrocarbons. 2 figures, 2 tables

  13. Anti radiation action of 'Vin-Vita' food additive solution in 'Kuyalnik' mineral water under sublethal gamma-irradiation conditions

    International Nuclear Information System (INIS)

    Baraboj, V.A.; Lobasyuk, B.O.; Oleksyijenko, N.O.; Kujev, V.L.; Goncharov, M.Yi.; Smul's'kij, S.P.; Kolker, Yi.A.; Babov, K.D.

    1996-01-01

    The study involved four groups of female Wistar rats. Protective anti radiation action of 'Vin-Vita' food additive solution in 'Kuyalnik' mineral water especially in the concentration of 500 mg/l has been revealed, which was proved by hemoglobin, hematocrit, ESR, white blood parameters and animal behaviour

  14. Large-scale Water-related Innovative Renewable Energy Projects and the Water Framework Directive : Legal Issues and Solutions

    NARCIS (Netherlands)

    van Hees, S.R.W.

    2017-01-01

    This article discusses two legal issues that relate to the conflict between the interest of protecting water quality under the Water Framework Directive (WFD), versus the interest of promoting the use of innovative water-related renewable energy, with regard to the quota in the Renewable Energy

  15. Ag-to-urban water transfer in California: Win-win solutions

    International Nuclear Information System (INIS)

    Jacobi, L.A.; Carley, R.L.

    1993-01-01

    The current long-term drought in California has generated interest in water transfers. Water transfers from farms to the cities are widely viewed as the next major source of supply to urban California. Ag-to-Urban permanent water transfers may have negative consequences to the agricultural sector and to the environment. This paper presents agricultural water use statistics, discusses sources of water for transfer, and suggests sources of water for win-win transfers

  16. The stability of high-Tc BSCCO/Ag superconducting microcomposites in water, some inorganic solutions and organic solvents

    International Nuclear Information System (INIS)

    Gao, W.; Chen, J.; Yang, C.O.; McNabb, D.; Sande, J. vander

    1992-01-01

    Bi(Pb)-Sr-Ca-Cu-O/Ag (BSCCO/Ag) superconducting microcomposites with zero-resistance temperatures from 102 to 108 K and critical current densities of ∝600 A/cm 2 at 77 K were produced by oxidation and annealling of metallic precursor alloys. The stabilities and degradation behavior of BSCCO/Ag specimens in various environments were studied by a combination of mass loss measurement, electrical transport measurement and microstructural observation. The environmental conditions used in the present work were moist air, distilled water, aqueous solutions of NaCl, NaOH and acetic acid, and organic solvents methanol and acetone. Although there is a general tendency toward a decrease in critical current density after a long exposure to most of the testing conditions, the specimens containing a high percent of Ag (≥70 wt.%) showed very little decrease in Tc and J c up to 200 days of exposure in moist air and distilled water, and up to 20 days in NaCl solution, methanol and acetone. It was found that the superconducting ''2223'' phase is stable in water, neutral solutions and the organic solvents, reacts very slowly with basic solutions, and dissolves rapidly in acidic solutions. Some non-superconducting Ca-rich oxides dissolve in water and neutral and basic solutions and therefore damage the connection of the superconducting grains in low-Ag containing specimens. The excellent stability of the BSCCO/Ag superconducting microcomposites containing high Ag provides an important advantage for their potential industrial application. (orig.)

  17. Experimental Study of the Effect for Water Depth on the Mass Transfer of Passive Solar Still Chemical Solutions

    Directory of Open Access Journals (Sweden)

    Fayadh M. Abed

    2018-01-01

    Full Text Available An experimental study on a passive solar distiller in the Tikrit city on (latitude line"34 36o north, longitude line "45 43o east, and purpose of that study to raise the efficiency and productivity of the solar distiller. And then design the monoclinic solar distiller and add reflector plate and a solar concentrate. The Practical tests were conducted at a rate of every half-hour from the beginning of February to the beginning of the month of June. The study began by comparing the solar distiller that contain the concentrates and without contain it. Then study the influence of adding coal and chemical solutions, like blue Thymol solution and blue bromophenol solution to see the additions effect on the productivity and efficiency of distiller, and also The study was conducted to see the effect of the water depth on the productivity of distiller with take four water depths within the basin are (2,1.5,1,0.5 cm of water. The tests were conducted in weather conditions close. and the results of the study, That distilled added his concentrates improved its productivity by 46% and efficiency increases 43% with non-use of concentrates, and coal increased efficiency by 36% and productivity improved up to 38%, the addition of  blue Thymol solution increases the efficiency by 19% and productivity by 16%, as well as bromophenol solution  increase productivity by 23% and improve efficiency by 25%, when comparing the additions found that the best one is coal. Through the study of the depth of the water show that increases productivity and efficiency by reducing the depth of the water in the basin distiller. DOI: http://dx.doi.org/10.25130/tjes.24.2017.13

  18. Conceptual design of stepper motor replacing servo motor for control rod controller

    International Nuclear Information System (INIS)

    Mohd Dzul Aiman Aslan; Mohd Idris Taib; Izhar Abu Hussin; Mohd Khairulezwan Abdul Manan; Mohd Sabri Minhat

    2010-01-01

    In PUSPATI TRIGA Reactor, current control rod controller are using servo motor to control the movement. Control rod is a very important safety element and measure in every nuclear reactor. So, precision is very important in measurement of security in the nuclear reactor. In this case, there are a few disadvantages when using the servo motor is measurement of the motor is not precise. One solution to overcome this is by shifting servo motor with stepper motor. A stepper motor (or step motor) is a brush less, synchronous electric motor that can divide a full rotation into a large number of steps. (author)

  19. Adsorption characteristics of sulfur solution by acticarbon against drinking-water toxicosis.

    Science.gov (United States)

    Ge, Shengbo; Liu, Zhenling; Furuta, Yuzo; Peng, Wanxi

    2017-09-01

    , 600 cm -1 achieved the maximum with 2 g/1000 g at 100 min. It provided that acticarbon could adsorb and desulphurize from sulfur solution against drinking-water toxicosis.

  20. Adsorption characteristics of sulfur solution by acticarbon against drinking-water toxicosis

    Directory of Open Access Journals (Sweden)

    Shengbo Ge

    2017-09-01

    from sulfur solution against drinking-water toxicosis.

  1. Technical solutions for tritium removal from Cernavoda NPP heavy water systems

    International Nuclear Information System (INIS)

    Barariu, Gheorghe; Panait, Adrian

    2002-01-01

    In CANDU nuclear plants 2400 KCi/GW(e) - year tritium is generated. At a CANDU - 600 reactor similar to Cernavoda NPP Unit 1, 1500 KCi/year of tritium is generated 95% being in the D 2 O moderator, which can achieve a radioactivity level of 80 - 100 Ci/kg. Tritium in heavy water contributes with 30 - 50% to the doses received by operation personnel and with 20% to the radioactivity released to the environment. The extraction of tritium heavy water at CANDU reactors implies the following possibilities: - the radioactivity level reduction in the operation area; - the maintenance and repair cost reduction due to reduction of personnel protection measures and increased labor productivity; - the increase of NPP utilization factor by shutdown time reduction for maintenance and repair; - tritium concentration reduction from technological systems, ensuring thus the possibility of redesigning the systems in order to lower the cost of investment; - profitable use of extracted tritium. Technical measures provided by AECL project for CANDU 600 at Cernavoda make possible to satisfy the current standards concerning tritium concentration in the operation area atmosphere of 5 x 10 -6 Ci/m 3 . The regulations recommend that the radioactivity level should be maintained as low as possible in conformity with ALARA principles. Also, it is possible that norms will become more restrictive in the future, so the tritium removal technology is a good preventive measure which may become very necessary. The methods, which currently reached the industrial or pilot stages, are based on catalyzed chemical exchange, the heavy water electrolysis, and deuterium distillation. They are known as: VPCE - Vapour Phase Catalytic Exchange; LPCE - Liquid Phase Catalytic Exchange; DE - Direct Electrolysis; CD - Cryogenic Distillation. As transfer processes the catalyzed chemical exchange and heavy water electrolysis are used while concentration of tritium gas is done by cryogenic distillation. At present the

  2. Molecular mechanics and microcalorimetric investigations of the effects of molecular water on the aggregation of asphaltenes in solutions

    DEFF Research Database (Denmark)

    Murgich, J.; Lira-Galeana, C.; Garcia, Daniel Merino

    2002-01-01

    The interaction of two model asphaltene molecules from the Athabasca sand oil with a water molecule in a toluene solution was studied by means of molecular mechanics calculations. It was found that water forms bridging H bonds between the heteroatoms of asphaltenes with a considerable span...... in energies. The stronger H bond found has energies higher than those corresponding to the stacking of the aromatic areas of the same asphaltene molecules. This shows that the water molecule may generate additional mechanisms of aggregation of asphaltenes in toluene solution, as found experimentally. The H...... by titration calorimetry. A simple dimer dissociation model was used to derive the information about the heat and the constant of dissociation from asphaltenes of Mexico and Alaska obtained from the calorimetric data. The association enthalpies calculated were found to be in excellent agreement with those...

  3. Life Cycle Network Modeling Framework and Solution Algorithms for Systems Analysis and Optimization of the Water-Energy Nexus

    Directory of Open Access Journals (Sweden)

    Daniel J. Garcia

    2015-07-01

    Full Text Available The water footprint of energy systems must be considered, as future water scarcity has been identified as a major concern. This work presents a general life cycle network modeling and optimization framework for energy-based products and processes using a functional unit of liters of water consumed in the processing pathway. We analyze and optimize the water-energy nexus over the objectives of water footprint minimization, maximization of economic output per liter of water consumed (economic efficiency of water, and maximization of energy output per liter of water consumed (energy efficiency of water. A mixed integer, multiobjective nonlinear fractional programming (MINLFP model is formulated. A mixed integer linear programing (MILP-based branch and refine algorithm that incorporates both the parametric algorithm and nonlinear programming (NLP subproblems is developed to boost solving efficiency. A case study in bioenergy is presented, and the water footprint is considered from biomass cultivation to biofuel production, providing a novel perspective into the consumption of water throughout the value chain. The case study, optimized successively over the three aforementioned objectives, utilizes a variety of candidate biomass feedstocks to meet primary fuel products demand (ethanol, diesel, and gasoline. A minimum water footprint of 55.1 ML/year was found, economic efficiencies of water range from −$1.31/L to $0.76/L, and energy efficiencies of water ranged from 15.32 MJ/L to 27.98 MJ/L. These results show optimization provides avenues for process improvement, as reported values for the energy efficiency of bioethanol range from 0.62 MJ/L to 3.18 MJ/L. Furthermore, the proposed solution approach was shown to be an order of magnitude more efficient than directly solving the original MINLFP problem with general purpose solvers.

  4. Mitigation options for chemicals of emerging concern in surface waters operationalising solutions-focused risk assessment

    NARCIS (Netherlands)

    Van Wezel, Annemarie P.; Ter Laak, Thomas L.; Fischer, Astrid; Bäuerlein, Patrick S.; Munthe, John; Posthuma, Leo

    2017-01-01

    The water system provides many services to society; industries, municipalities and agriculture all withdraw, use and return water and demand a water quality fit for the intended purposes. Both global production of chemicals and global water withdrawal grow faster than human population. This implies

  5. Induction of micronuclei by 2-hydroxypyridine in water and elimination of solution genotoxicity by UVC (254 nm) photolysis

    International Nuclear Information System (INIS)

    Skoutelis, Charalambos G.; Vlastos, Dimitris; Kortsinidou, Marianna C.; Theodoridis, Ioannis T.; Papadaki, Maria I.

    2011-01-01

    Highlights: ► 2-Hydroxypyridine (2-HPY) is the major metabolite of 2-halogenated pyridines photolysis. ► We examine the genotoxicity of 2-HPY in cultured human lymphocytes applying the micronucleus assay. ► 2-HPY was found to be genotoxic. ► Aqueous solutions of 2-HPY were irradiated by UV at 254 nm. ► Solution genotoxicity can be completely removed after prolonged phototreatment. - Abstract: 2-Hydroxypyridine (2-HPY) is a major first-stage product formed upon the photolytic destruction of 2-halogenated pyridines. Genotoxicity of 2-HPY in water was studied as a function of concentration. Aqueous solutions of 2-HPY were irradiated by ultraviolet (UV) at 254 nm. 2-HPY concentration, solution total organic carbon (TOC) concentration and solution genotoxicity were measured as a function of treatment time and their profile as a function of time is presented in this work. 2-HPY was found to be genotoxic at all concentrations in the range of 5–400 μg ml −1 . 2-HPY mineralises completely upon prolonged UV irradiation. All untreated and irradiated solution samples, taken at different photo-treatment times, were tested in cultured human lymphocytes applying the cytokinesis block micronucleus (CBMN) assay. The genotoxicity of the solution was reduced near to the control level after prolonged UV irradiation.

  6. Higher Efficiency HVAC Motors

    Energy Technology Data Exchange (ETDEWEB)

    Flynn, Charles Joseph [QM Power, Inc., Kansas City, MO (United States)

    2018-02-13

    The objective of this project was to design and build a cost competitive, more efficient heating, ventilation, and air conditioning (HVAC) motor than what is currently available on the market. Though different potential motor architectures among QMP’s primary technology platforms were investigated and evaluated, including through the building of numerous prototypes, the project ultimately focused on scaling up QM Power, Inc.’s (QMP) Q-Sync permanent magnet synchronous motors from available sub-fractional horsepower (HP) sizes for commercial refrigeration fan applications to larger fractional horsepower sizes appropriate for HVAC applications, and to add multi-speed functionality. The more specific goal became the research, design, development, and testing of a prototype 1/2 HP Q-Sync motor that has at least two operating speeds and 87% peak efficiency compared to incumbent electronically commutated motors (EC or ECM, also known as brushless direct current (DC) motors), the heretofore highest efficiency HVACR fan motor solution, at approximately 82% peak efficiency. The resulting motor prototype built achieved these goals, hitting 90% efficiency and .95 power factor at full load and speed, and 80% efficiency and .7 power factor at half speed. Q-Sync, developed in part through a DOE SBIR grant (Award # DE-SC0006311), is a novel, patented motor technology that improves on electronically commutated permanent magnet motors through an advanced electronic circuit technology. It allows a motor to “sync” with the alternating current (AC) power flow. It does so by eliminating the constant, wasteful power conversions from AC to DC and back to AC through the synthetic creation of a new AC wave on the primary circuit board (PCB) by a process called pulse width modulation (PWM; aka electronic commutation) that is incessantly required to sustain motor operation in an EC permanent magnet motor. The Q-Sync circuit improves the power factor of the motor by removing all

  7. The water extract of Liuwei dihuang possesses multi-protective properties on neurons and muscle tissue against deficiency of survival motor neuron protein.

    Science.gov (United States)

    Tseng, Yu-Ting; Jong, Yuh-Jyh; Liang, Wei-Fang; Chang, Fang-Rong; Lo, Yi-Ching

    2017-10-15

    Deficiency of survival motor neuron (SMN) protein, which is encoded by the SMN1 and SMN2 genes, induces widespread splicing defects mainly in spinal motor neurons, and leads to spinal muscular atrophy (SMA). Currently, there is no effective treatment for SMA. Liuwei dihuang (LWDH), a traditional Chinese herbal formula, possesses multiple therapeutic benefits against various diseases via modulation of the nervous, immune and endocrine systems. Previously, we demonstrated water extract of LWDH (LWDH-WE) protects dopaminergic neurons and improves motor activity in models of Parkinson's disease. This study aimed to investigate the potential protection of LWDH-WE on SMN deficiency-induced neurodegeneration and muscle weakness. The effects of LWDH-WE on SMN deficiency-induced neurotoxicity and muscle atrophy were examined by using SMN-deficient NSC34 motor neuron-like cells and SMA-like mice, respectively. Inducible SMN-knockdown NSC34 motor neuron-like cells were used to mimic SMN-deficient condition. Doxycycline (1 µg/ml) was used to induce SMN deficiency in stable NSC34 cell line carrying SMN-specific shRNA. SMAΔ7 mice were used as a severe type of SMA mouse model. Cell viability was measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT) and lactate dehydrogenase (LDH) assays. Apoptotic cells and neurite length were observed by inverted microscope. Protein expressions were examined by western blots. Muscle strength of animals was evaluated by hind-limb suspension test. LWDH-WE significantly increased SMN protein level, mitochondrial membrane potential and cell viability of SMN-deficient NSC34 cells. LWDH-WE attenuated SMN deficiency-induced down-regulation of B-cell lymphoma-2 (Bcl-2) and up-regulation of cytosolic cytochrome c and cleaved caspase-3. Moreover, LWDH-WE prevented SMN deficiency-induced inhibition of neurite outgrowth and activation of Ras homolog gene family, member A (RhoA)/ Rho-associated protein kinase (ROCK2)/ phospho

  8. A new unconditionally stable and consistent quasi-analytical in-stream water quality solution scheme for CSTR-based water quality simulators

    Science.gov (United States)

    Woldegiorgis, Befekadu Taddesse; van Griensven, Ann; Pereira, Fernando; Bauwens, Willy

    2017-06-01

    Most common numerical solutions used in CSTR-based in-stream water quality simulators are susceptible to instabilities and/or solution inconsistencies. Usually, they cope with instability problems by adopting computationally expensive small time steps. However, some simulators use fixed computation time steps and hence do not have the flexibility to do so. This paper presents a novel quasi-analytical solution for CSTR-based water quality simulators of an unsteady system. The robustness of the new method is compared with the commonly used fourth-order Runge-Kutta methods, the Euler method and three versions of the SWAT model (SWAT2012, SWAT-TCEQ, and ESWAT). The performance of each method is tested for different hypothetical experiments. Besides the hypothetical data, a real case study is used for comparison. The growth factors we derived as stability measures for the different methods and the R-factor—considered as a consistency measure—turned out to be very useful for determining the most robust method. The new method outperformed all the numerical methods used in the hypothetical comparisons. The application for the Zenne River (Belgium) shows that the new method provides stable and consistent BOD simulations whereas the SWAT2012 model is shown to be unstable for the standard daily computation time step. The new method unconditionally simulates robust solutions. Therefore, it is a reliable scheme for CSTR-based water quality simulators that use first-order reaction formulations.

  9. Analytical solutions for benchmarking cold regions subsurface water flow and energy transport models: one-dimensional soil thaw with conduction and advection

    Science.gov (United States)

    Kurylyk, Barret L.; McKenzie, Jeffrey M; MacQuarrie, Kerry T. B.; Voss, Clifford I.

    2014-01-01

    Numerous cold regions water flow and energy transport models have emerged in recent years. Dissimilarities often exist in their mathematical formulations and/or numerical solution techniques, but few analytical solutions exist for benchmarking flow and energy transport models that include pore water phase change. This paper presents a detailed derivation of the Lunardini solution, an approximate analytical solution for predicting soil thawing subject to conduction, advection, and phase change. Fifteen thawing scenarios are examined by considering differences in porosity, surface temperature, Darcy velocity, and initial temperature. The accuracy of the Lunardini solution is shown to be proportional to the Stefan number. The analytical solution results obtained for soil thawing scenarios with water flow and advection are compared to those obtained from the finite element model SUTRA. Three problems, two involving the Lunardini solution and one involving the classic Neumann solution, are recommended as standard benchmarks for future model development and testing.

  10. Ultrasonic speed, densities and viscosities of xylitol in water and in aqueous tyrosine and phenylalanine solutions at different temperatures

    Science.gov (United States)

    Ali, A.; Bidhuri, P.; Uzair, S.

    2014-07-01

    Ultrasonic speed u, densities ρ and viscosities η of xylitol in water and in 0.001 m aqueous l-tyrosine (Tyr) and l-phenylalanine (Phe) have been measured at different temperatures. From the density and ultrasonic speed measurements apparent molar isentropic compression κ_{φ}, apparent molar isentropic compressions at infinite dilution κ_{{S,φ}}0 , experimental slope S K , hydration number n H , transfer partial molar isentropic compressibility Δ_{tr} κ_{{S,φ}}0 of xylitol from water to aqueous Tyr and Phe have been obtained. From the viscosity data, B-coefficient and B-coefficient of transfer Δ tr B of xylitol from water to aqueous Phe and Tyr at different temperatures have also been estimated. Gibbs free energies of activation of viscous flow per mole of solvent Δ μ 1 0# and per mole of solute Δ μ 2 0# have been calculated by using Feakins transition state theory for the studied systems. The calculated parameters have been interpreted in terms of solute-solute and solute-solvent interactions and hydration behavior of xylitol.

  11. Dichlorvos (DDVP residue removal from tomato by washing with tap and ozone water, a commercial detergent solution and ultrasonic cleaner

    Directory of Open Access Journals (Sweden)

    Ali HESHMATI

    Full Text Available Abstract Dichlorvos (DDVP is one of the most consumption chlorinated organophosphate insecticide used on tomato. The knowledge about the influence of postharvest household processes on the levels of DDVP residues in vegetables is required to estimate dietary exposure. In this study, the removal of sprayed dichlorvos (DDVP on tomato by washing with tap, ozonated water (in dosages of 2, 4 and 6 mg ozone/L, a commercial detergent solution (in concentration of 1, 2 and 3% and ultrasonic cleaner (with power of 100, 200 and 300 W was investigated. DDVP residue was determined by gas chromatography with electron capture detector. Washing processes led to the significant reduction of DDVP. The gradual increase in the percentage of the removal was observed due to increment of washing time, ozone dosage, and concentration of detergent solution as well as ultrasonic power. The maximum removal percentage of DDVP after 15 min of washing with tap and ozonated water, a detergent solution and ultrasonic cleaner was 30.7, 91.9, 70.7, and 88.9%, respectively. In general, results indicated washing with tap, ozonated water, a detergent solution and ultrasonic cleaning are effective methods for removal of DDVP from tomato and reduction of its dietary exposure without influence on product quality.

  12. Alternative solutions for inhibiting Legionella in domestic hot water systems based on low-temperature district heating

    DEFF Research Database (Denmark)

    Yang, Xiaochen; Li, Hongwei; Svendsen, Svend

    2015-01-01

    Abstract District heating is a cost-effective way of providing heat to high heat density areas. Low-temperature district heating (LTDH) is a promising way to make district heating more energy-efficient and adaptable to well-insulated buildings with low heating demand in the future. However, one c...... systems. They have the additional benefit of reducing the heat loss of the hot water system. The alternative design solutions both enrich our options for water sanitation and improve the energy efficiency of our energy systems....... concern is the multiplication of Legionella due to insufficient temperature elevation with low-temperature supply. The aim of this study was to find optimal solutions to this dilemma for specific situations. The solutions were of two types: alternative system designs and various methods of sterilization...... methods, thermal treatment, ionization, chlorine, chlorine dioxide, ultraviolet light, photocatalysis and filtration are discussed as the most frequently used methods in hot water systems. The characteristics, efficacy and operation methods of LTDH using the solutions investigated are documented...

  13. Barley root hair growth and morphology in soil, sand, and water solution media and relationship with nickel toxicity.

    Science.gov (United States)

    Lin, Yanqing; Allen, Herbert E; Di Toro, Dominic M

    2016-08-01

    Barley, Hordeum vulgare (Doyce), was grown in the 3 media of soil, hydroponic sand solution (sand), and hydroponic water solution (water) culture at the same environmental conditions for 4 d. Barley roots were scanned, and root morphology was analyzed. Plants grown in the 3 media had different root morphology and nickel (Ni) toxicity response. Root elongations and total root lengths followed the sequence soil > sand > water. Plants grown in water culture were more sensitive to Ni toxicity and had greater root hair length than those from soil and sand cultures, which increased root surface area. The unit root surface area as root surface area per centimeter of length of root followed the sequence water > sand > soil and was found to be related with root elongation. Including the unit root surface area, the difference in root elongation and 50% effective concentration were diminished, and percentage of root elongations can be improved with a root mean square error approximately 10% for plants grown in different media. Because the unit root surface area of plants in sand culture is closer to that in soil culture, the sand culture method, not water culture, is recommended for toxicity parameter estimation. Environ Toxicol Chem 2016;35:2125-2133. © 2016 SETAC. © 2016 SETAC.

  14. 33 CFR 159.69 - Motor ratings.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Motor ratings. 159.69 Section 159.69 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) POLLUTION MARINE SANITATION DEVICES Design, Construction, and Testing § 159.69 Motor ratings. Motors must be rated...

  15. Photoelectron spectroscopy of liquid water and aqueous solution: Electron effective attenuation lengths and emission-angle anisotropy

    Energy Technology Data Exchange (ETDEWEB)

    Ottosson, Niklas [Department of Physics, Uppsala University, SE-75121 Uppsala (Sweden); Faubel, Manfred [Max-Planck-Institut fuer Dynamik und Selbstorganisation, Bunsenstrasse 10, D-37073 Goettingen (Germany); Bradforth, Stephen E. [Department of Chemistry, University of Southern California, Los Angeles, CA 90089 (United States); Jungwirth, Pavel [Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, and Center for Biomolecules and Complex Molecular Systems, Flemingovo nam. 2, 16610 Prague 6 (Czech Republic); Winter, Bernd, E-mail: winter@bessy.d [Helmholtz-Zentrum Berlin fuer Materialien und Energie, and BESSY, Albert-Einstein-Strasse 15, D-12489 Berlin (Germany); Max-Born-Institut, Max-Born-Strasse 2A, D-12489 Berlin (Germany)

    2010-03-15

    Photoelectron (PE) spectroscopy measurements from liquid water and from a 4 m NaI aqueous solution are performed using a liquid microjet in combination with soft X-ray synchrotron radiation. From the oxygen 1s PE signal intensity from liquid water, measured as a function of photon energy (up to 1500 eV), we quantitatively determine relative electron inelastic effective attenuation lengths (EAL) for (photo)electron kinetic energies in the 70-900 eV range. In order to determine the absolute electron escape depths a calibration point is needed, which is not directly accessible by experiment. This information can instead be indirectly derived by comparing PE experiments and molecular dynamics (MD) simulations of an aqueous solution interface where density profiles of water, anions, and cations are distinctively different. We have chosen sodium iodide in water because iodide has a considerable propensity for the solution surface, whereas the sodium cation is repelled from the surface. By measuring the intensities of photoelectrons emitted from different orbitals of different symmetries from each aqueous ion we also evaluate whether gas-phase ionization cross sections and asymmetry parameters can describe the photoemission from ions at and near the aqueous solution/vapor interface. We show that gas-phase data reproduce surprisingly well the experimental observations for hydrated ions as long as the photon energy is sufficiently far above the ionization threshold. Electrons detected at the higher photon energies originate predominantly from deeper layers, suggesting that bulk-solution electron elastic scattering is relatively weak.

  16. Farmers, Trust, and the Market Solution to Water Pollution: The Role of Social Embeddedness in Water Quality Trading

    Science.gov (United States)

    Mariola, Matt J.

    2012-01-01

    Water quality trading (WQT) is a market arrangement in which a point-source water polluter pays farmers to implement conservation practices and claims the resulting benefits as credits toward meeting a pollution permit. Success rates of WQT programs nationwide are highly variable. Most of the literature on WQT is from an economic perspective…

  17. Water Uptake By Mars Salt Analogs: An Investigation Of Stable Aqueous Solutions On Mars Using Raman Microscopy

    Science.gov (United States)

    Nuding, D.; Gough, R. V.; Jorgensen, S. K.; Tolbert, M. A.

    2013-12-01

    To understand the formation of briny aqueous solutions on Mars, a salt analog was developed to closely match the individual cation and anion concentrations as reported by the Wet Chemistry Laboratory aboard the Phoenix Lander. ';Instant Mars' is a salt analog developed to fully encompass the correct concentrations of magnesium, calcium, potassium, sodium, perchlorate, chloride, and sulfate ions. Using environmental Raman microscopy, we have studied the water uptake by the Instant Mars analog as a function of temperature and relative humidity. Water uptake was monitored using Raman spectroscopy in combination with optical microscopy. A MicroJet droplet generator was used to generate 30 μm diameter particles that were deposited onto a quartz disc. The particles undergo visual transformations as the relative humidity (RH) is increased and the presence of water uptake is confirmed by Raman spectroscopy. At -30° C, water uptake begins at ~ 35% RH as humidity is increased. The water uptake is marked by the growth of a sulfate peak at 990 cm-1, an indicator that sulfate has undergone a phase transition into an aqueous state. As the RH continues to increase, the peak in the O-H region (~3500 cm-1) broadens as more liquid water accumulates in the particles. The Instant Mars particles achieve complete deliquescence at 68% RH, indicated both visually and with Raman spectroscopy. The gradual water uptake observed suggests that deliquescence of the Instant Mars particles is not an immediate process, but that it occurs in steps marked by the deliquescence of the individual salts. Perhaps of even more significance is the tendency for the Instant Mars particles to remain aqueous at low humidity as RH is decreased. Raman spectra indicate that liquid water is present as low as 2% RH at -30° C. Ongoing work will examine the phase of Instant Mars particles under simulated Martian surface and subsurface conditions to gain insight into the possibility for aqueous solutions on Mars

  18. Direct numerical solution of the Ornstein-Zernike integral equation and spatial distribution of water around hydrophobic molecules

    Science.gov (United States)

    Ikeguchi, Mitsunori; Doi, Junta

    1995-09-01

    The Ornstein-Zernike integral equation (OZ equation) has been used to evaluate the distribution function of solvents around solutes, but its numerical solution is difficult for molecules with a complicated shape. This paper proposes a numerical method to directly solve the OZ equation by introducing the 3D lattice. The method employs no approximation the reference interaction site model (RISM) equation employed. The method enables one to obtain the spatial distribution of spherical solvents around solutes with an arbitrary shape. Numerical accuracy is sufficient when the grid-spacing is less than 0.5 Å for solvent water. The spatial water distribution around a propane molecule is demonstrated as an example of a nonspherical hydrophobic molecule using iso-value surfaces. The water model proposed by Pratt and Chandler is used. The distribution agrees with the molecular dynamics simulation. The distribution increases offshore molecular concavities. The spatial distribution of water around 5α-cholest-2-ene (C27H46) is visualized using computer graphics techniques and a similar trend is observed.

  19. Effects of coal gangue content on water movement and solute transport in a China loess plateau soil

    Energy Technology Data Exchange (ETDEWEB)

    Beibei, Zhou; Quanjiu, Wang [Institute of Water Resources and Hydro-electric Engineering, Xi' an University of Technology, Xi' an (China); State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, Northwest A and F University, Yangling, Shaanxi (China); Ming' an, Shao; Mingxia, Wen [State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, Northwest A and F University, Yangling, Shaanxi (China); College of Resources and Environment, Northwest A and F University, Yangling, Shaanxi (China); Horton, Robert [Department of Agronomy, Iowa State University, Ames, Iowa (United States)

    2010-11-15

    The mining industry has grown strongly in China in recent decades, resulting in large amounts of coal gangues, which cause water and soil pollution, soil erosion, and various other environmental problems. They are often used in reclamation projects in attempts to restore land damaged by mining, hence they are frequently present (in widely varying proportions) in the topsoil in areas around mines. Their presence can strongly affect key soil variables, including its bulk density, structure, water retention, water movement, and solute transport rates. In the study presented here, the effects of gangue contents on infiltration, saturated hydraulic conductivity, and solute transport parameters of a Chinese Loess plateau soil were examined. The results show that infiltration rates and saturated hydraulic conductivity decreased with increasing gangue content. The Peck-Watson equation modeled these relationships well, but Bouwer-Rice equations provided poorer matches with the acquired data. Cumulative infiltration over time was described well by both the Philip equation and Kostiakov equation. Both the simplified convection-dispersion equation and a two-region model described the solute transport processes well. In addition, the dispersion increased, while both the Peclet number and mobile water fraction decreased, with increases in gangue contents. (Copyright copyright 2010 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  20. Characterizing the correlation between dephosphorization and solution pH in a calcined water treatment plant sludge.

    Science.gov (United States)

    Zhou, Zhenming; Liu, Qidi; Li, Shuwen; Li, Fei; Zou, Jing; Liao, Xiaobin; Yuan, Baoling; Sun, Wenjie

    2018-04-26

    This study focused on characterizing the correlation between the dephosphorization process of calcined water treatment plant sludge (C-WTPS) and the solution initial pH in batch experiments. The specific aim was to illustrate the effect of different initial pH on the adsorption and desorption of phosphorous in C-WTPS. In addition, the effects of solution initial pH on the release of ammonia nitrogen and total organic carbon (TOC) from C-WTPS and the change of pH after adsorption were also investigated. The results demonstrated that the initial pH significantly influenced the adsorption of phosphorus on C-WTPS. When initial pH was increased from 3 to 10, the phosphorous absorption capacity reduced by 76.5%. Especially, when the initial pH reached to 11, the phosphorus adsorption capacity became a negative value, indicating that C-WTPS released phosphorus into the solution. The addition of C-WTPS to the solution had little impact on the initial pH of the solution. The absorbed phosphorous on C-WTPS was relatively stable in the pH range of 3 to 10. Nevertheless, when the solution pH was higher than 11, it can be easily released into the solution. Furthermore, by comparison with WTPS, C-WTPS released less ammonia nitrogen and TOC into the solution and adsorbed more phosphorus from the solution in the experimental pH range. Therefore, C-WTPS is more suitable to serve as a cost-effective sorbent for phosphorus removal.

  1. Classification of the Group Invariant Solutions for Contaminant Transport in Saturated Soils under Radial Uniform Water Flows

    Directory of Open Access Journals (Sweden)

    M. M. Potsane

    2014-01-01

    Full Text Available The transport of chemicals through soils to the groundwater or precipitation at the soils surfaces leads to degradation of these resources. Serious consequences may be suffered in the long run. In this paper, we consider macroscopic deterministic models describing contaminant transport in saturated soils under uniform radial water flow backgrounds. The arising convection-dispersion equation given in terms of the stream functions is analyzed using classical Lie point symmetries. A number of exotic Lie point symmetries are admitted. Group invariant solutions are classified according to the elements of the one-dimensional optimal systems. We analyzed the group invariant solutions which satisfy the physical boundary conditions.

  2. Synthesis and spectral properties of axially substituted zirconium(IV) and hafnium(IV) water soluble phthalocyanines in solutions

    International Nuclear Information System (INIS)

    Gerasymchuk, Y.S.; Volkov, S.V.; Chernii, V.Ya.; Tomachynski, L.A.; Radzki, St.

    2004-01-01

    Methods of synthesis of novel water soluble axially substituted Zr(IV) and Hf(IV) phthalocyanines with gallic, 5-sulfosalicyllic, oxalic acids, and methyl ester of gallic acid as axial ligands coordinated to the central atom metal of phthalocyanine are presented. The absorption spectra of complex solutions in various solvents were characterized. The dependence of the spectral red shift from Reichardt's empirical polarity parameter is described. The deviation from the linearity of Beer-Bouguer-Lambert law was investigated for the range of concentration 5x10 -6 to 10x10 -5 M. Fluorescent properties of axially substituted phthalocyaninato metal complexes in DMSO solutions were investigated

  3. Enthalpies of Dissolution of Crystalline Naproxen Sodium in Water and Potassium Hydroxide Aqueous Solutions at 298 K

    Science.gov (United States)

    Lytkin, A. I.; Chernikov, V. V.; Krutova, O. N.; Bychkova, S. A.; Volkov, A. V.; Skvortsov, I. A.

    2018-03-01

    The enthalpies of dissolution of crystalline naproxen sodium in water and aqueous solutions of KOH at 298.15 K are measured by direct calorimetric means in a wide range of concentrations. The acid-base properties of naproxen sodium at ionic strength I 0 and I = 0.1 (KNO3) and a temperature of 298.15 K are studied by spectrophotometric means. The concentration and thermodynamic dissociation constants are determined. The standard enthalpies of the formation of naproxen sodium and the products of its dissociation in aqueous solution are calculated.

  4. Predicting Hyporheic Exchange of Water and Solutes in Streams on the Basis of a Priori Estimates of Stream Physical Characteristics

    Science.gov (United States)

    Stone, S. H.; Harvey, J.; Packman, A.; Worman, A.

    2005-12-01

    It is very important to accurately model solute transport in rivers in order to analyze contaminant transport, water quality, and a variety of ecological processes. The purpose of this research is to determine the physical characteristics of a stream or river that are sufficient to predict hyporheic exchange and downstream solute transport. In the fall of 2004, we conducted a bromide tracer injection and made physical measurements in Sugar Creek, a small agricultural stream in northwestern Indiana. As is typical for small mid-western agricultural streams, Sugar Creek has been ditched and straightened, and subsequent downcutting through glacial sediments and slumpage of bank sediments composed of finer grain sizes has created a stream of intermediate complexity. In order to relate the observed solute transport to more basic physical characteristics of the stream, we determined the bathymetry of Sugar Creek over a wide range of scales (centimeters to decameters), and measured velocity profiles, the water elevation surface profile, hydraulic conductivity via in situ measurements, and bed sediment grain size distributions throughout the study reach. Our most detailed topographic measurements revealed fine scale bed variations with wavelengths on the order of ten centimeters, while surveying of the entire study reach characterized large scale meanders with wavelengths on the order of five meters. The distribution of wavelengths influences the driving forces that cause solute to enter the bed and banks. Hydraulic conductivity determines the resistance to flow of stream water through the (meander) stream banks and streambed. We used a scaling approach to relate the geometric and hydrogeologic characteristics of the stream to solute transport and also applied a new analytical solution for the subsurface flows resulting from topographic variations over a wide range of spatial scales. These models captured the main features of the observed solute transport. The greatest

  5. Considerations Regarding the Opportunity of Using Psychological Techniques to Stimulate Solutions Characterized by Novelty and Inventive Step in TISR Transformers and Electric Motors with Shorted Moving Coil

    Directory of Open Access Journals (Sweden)

    Georgescu Daniel Ștefan

    2014-09-01

    Full Text Available This paper presents the appreciations and contributions regarding the use of psychological techniques to stimulate technical creativity with special reference to consonant association technique and inversion technique. The study is performed in the field of TISR transformers and electric motors with limited movement, starting from the analogy between a transformer and an electric motor with shorted coil. It approached a particular aspect of inversion technique in relation with the transformation of negative effects and results of laws, phenomena and processes into useful applications. The matter reffered to is related to the question: ,,why disadvantages and no advantages ?". At the end of the paper are presented and discussed some experimental models produced and studied by the authors in the Research Laboratory of Machines, Equipment and Drives at the University of Suceava and are exposed conclusions drawn from the experimental study and directions for future research.

  6. Accumulation of dissolved gases at hydrophobic surfaces in water and sodium chloride solutions: Implications for coal flotation

    Energy Technology Data Exchange (ETDEWEB)

    Hampton, M.A.; Nguyen, A.V. [University of Queensland, Brisbane, Qld. (Australia). Division of Chemical Engineering

    2009-08-15

    Dissolved gases can preferentially accumulate at the hydrophobic solid-water interface as revealed by neutron reflectivity measurements. In this paper, atomic force microscopy (AFM) was used to examine accumulation of dissolved gases at a hydrophobic surface in water and sodium chloride solutions. The solvent-exchange method was used to artificially form gaseous domains accumulated at the interface suitable for AFM imaging. Smooth graphite surfaces were used as model surfaces to minimize the secondary effect of surface roughness on the imaging. The concentration of NaCl up to 1 M was found to have a negligible influence on the geometry and population of pre-existing nanobubbles, nanopancakes and nanobubble-nanopancake composites. The implications of the findings on coal flotation in saline water are discussed in terms of attraction between hydrophobic surfaces in water, bubble-particle attachment and hydrophobic coagulation between particles.

  7. Experimental study of formation and dynamics of cavitation bubbles and acoustic flows in NaCl, KCl water solutions

    Science.gov (United States)

    Rybkin, K. A.; Bratukhin, Yu. K.; Lyubimova, T. P.; Fatallov, O.; Filippov, L. O.

    2017-07-01

    The acoustic flows and the phenomena associated with them arising under the action of ultrasound of different power on distilled water and aqueous solutions of a mixture of NaCl and KCl salts of various concentrations are studied experimentally. It is found that in the distilled water, under the action of ultrasound, the appearance of inertial and non-inertial cavitation bubbles takes place, then the formation of stable clusters, the distance between which depends on the power of the ultrasound source is observed. Experiments show that an increase in the mass concentration of salts in water leads to the decrease in the average diameter of the arising inertial cavitation bubbles and to the gradual decrease in their number, up to an almost complete disappearance at nearly 13% of the concentration of the salt mixture in the water.

  8. Water resources management: traditional technology and communities as part of the solution

    Science.gov (United States)

    Hussain, J.; Husain, I.; Arif, M.

    2014-09-01

    Rajasthan, the largest State in India, has one of the most critical water statuses. Rajasthan, with more than 10.4 % of the country's geographical area, supports more than 5.5 % of the human population and 18.70 % of the livestock, but only has 1.16 % of the total surface water available in the country. More than 60 % of the state is a part of the Great Thar Desert, and of the total 142 desert blocks in the country, 85 blocks are in the state of Rajasthan. The per capita annual water availability in the state is about 780 m3, compared with the minimum requirement of 1000 m3. It is feared that the availability would fall below 450 m3 by the year 2050. Thus, increasing population coupled with erratic rainfall further aggravates the water crisis. It is possible to harvest and augment water resources through the construction of small water harvesting structures called johads and the implementation of local water governance. This has been amply demonstrated by the successful experience of local communities in Alwar District in Rajasthan. Since 1985, 8600 johads have been built in 1086 villages. This has resulted in the rise in water levels in the shallow aquifer, increase in the area under single and double crops, increase in forest cover and drinking water supply security. The water collected in a johad during the monsoon penetrates into the sub-soil. This recharges the groundwater and improves the soil moisture in vast areas. The water in the johad can be used directly for irrigation, drinking water by animals, and other domestic purposes. The other advantage of this structure is that it checks soil erosion, mitigates floods, and ensures water availability in wells or boreholes used for drinking water supply, even for several successive drought years. Also, during the dry season when the water gradually recedes in the johad, the land inside the johad itself becomes available for cultivation.

  9. Water resources management: traditional technology and communities as part of the solution

    Directory of Open Access Journals (Sweden)

    J. Hussain

    2014-09-01

    Full Text Available Rajasthan, the largest State in India, has one of the most critical water statuses. Rajasthan, with more than 10.4 % of the country’s geographical area, supports more than 5.5 % of the human population and 18.70 % of the livestock, but only has 1.16 % of the total surface water available in the country. More than 60 % of the state is a part of the Great Thar Desert, and of the total 142 desert blocks in the country, 85 blocks are in the state of Rajasthan. The per capita annual water availability in the state is about 780 m3, compared with the minimum requirement of 1000 m3. It is feared that the availability would fall below 450 m3 by the year 2050. Thus, increasing population coupled with erratic rainfall further aggravates the water crisis. It is possible to harvest and augment water resources through the construction of small water harvesting structures called johads and the implementation of local water governance. This has been amply demonstrated by the successful experience of local communities in Alwar District in Rajasthan. Since 1985, 8600 johads have been built in 1086 villages. This has resulted in the rise in water levels in the shallow aquifer, increase in the area under single and double crops, increase in forest cover and drinking water supply security. The water collected in a johad during the monsoon penetrates into the sub-soil. This recharges the groundwater and improves the soil moisture in vast areas. The water in the johad can be used directly for irrigation, drinking water by animals, and other domestic purposes. The other advantage of this structure is that it checks soil erosion, mitigates floods, and ensures water availability in wells or boreholes used for drinking water supply, even for several successive drought years. Also, during the dry season when the water gradually recedes in the johad, the land inside the johad itself becomes available for cultivation.

  10. Developing a cost effective environmental solution for produced water and creating a ''new'' water resource

    Energy Technology Data Exchange (ETDEWEB)

    Doran, Glenn; Leong, Lawrence Y.C.

    2000-05-01

    The project goal is to convert a currently usable by-product of oil production, produced water, into a valuable drinking water resource. The project was located at the Placate Oil Field in Santa Clarita, California, approximately 25 miles north of Los Angeles. The project included a literature review of treatment technologies; preliminary bench-scale studies to refine a planning level cost estimate; and a 10-100 gpm pilot study to develop the conceptual design and cost estimate for a 44,000 bpd treatment facility. A reverse osmosis system was constructed, pilot tested, and the data used to develop a conceptual design and operation of four operational scenarios, two industrial waters levels and two irrigation/potable water.

  11. A half-baked solution: drivers of water crises in Mexico

    Science.gov (United States)

    Godinez Madrigal, Jonatan; van der Zaag, Pieter; van Cauwenbergh, Nora

    2018-02-01

    Mexico is considered a regional economic and political powerhouse because of the size of its economy, and a large population in constant growth. However, this same growth accompanied by management and governance failures are causing several water crises across the country. The paper aims at identifying and analyzing the drivers of water crises. Water authorities seem to focus solely on large infrastructural schemes to counter the looming water crises, but fail to structure a set of policies for the improvement of management and governance institutions. The paper concludes with the implications of a business-as-usual policy based on infrastructure for solving water problems, which include a non-compliance to the human right to water and sanitation, ecosystem collapses and water conflicts.

  12. Simulation of ground-water flow and solute transport in the Glen Canyon aquifer, East-Central Utah

    Science.gov (United States)

    Freethey, Geoffrey W.; Stolp, Bernard J.

    2010-01-01

    The extraction of methane from coal beds in the Ferron coal trend in central Utah started in the mid-1980s. Beginning in 1994, water from the extraction process was pressure injected into the Glen Canyon aquifer. The lateral extent of the aquifer that could be affected by injection is about 7,600 square miles. To address regional-scale effects of injection over a decadal time frame, a conceptual model of ground-water movement and transport of dissolved solids was formulated. A numerical model that incorporates aquifer concepts was then constructed and used to simulate injection.The Glen Canyon aquifer within the study area is conceptualized in two parts—an active area of ground-water flow and solute transport that exists between recharge areas in the San Rafael Swell and Desert, Waterpocket Fold, and Henry Mountains and discharge locations along the Muddy, Dirty Devil, San Rafael, and Green Rivers. An area of little or negligible ground-water flow exists north of Price, Utah, and beneath the Wasatch Plateau. Pressurized injection of coal-bed methane production water occurs in this area where dissolved-solids concentrations can be more than 100,000 milligrams per liter. Injection has the potential to increase hydrologic interaction with the active flow area, where dissolved-solids concentrations are generally less than 3,000 milligrams per liter.Pressurized injection of coal-bed methane production water in 1994 initiated a net addition of flow and mass of solutes into the Glen Canyon aquifer. To better understand the regional scale hydrologic interaction between the two areas of the Glen Canyon aquifer, pressurized injection was numerically simulated. Data constraints precluded development of a fully calibrated simulation; instead, an uncalibrated model was constructed that is a plausible representation of the conceptual flow and solute-transport processes. The amount of injected water over the 36-year simulation period is about 25,000 acre-feet. As a result

  13. Adsorption at air-water and oil-water interfaces and self-assembly in aqueous solution of ethoxylated polysorbate nonionic surfactants.

    Science.gov (United States)

    Penfold, Jeffrey; Thomas, Robert K; Li, Peixun X; Petkov, Jordan T; Tucker, Ian; Webster, John R P; Terry, Ann E

    2015-03-17

    The Tween nonionic surfactants are ethoxylated sorbitan esters, which have 20 ethylene oxide groups attached to the sorbitan headgroup and a single alkyl chain, lauryl, palmityl, stearyl, or oleyl. They are an important class of surfactants that are extensively used in emulsion and foam stabilization and in applications associated with foods, cosmetics and pharmaceuticals. A range of ethoxylated polysorbate surfactants, with differing degrees of ethoxylation from 3 to 50 ethylene oxide groups, have been synthesized and characterized by neutron reflection, small-angle neutron scattering, and surface tension. In conjunction with different alkyl chain groups, this provides the opportunity to modify their surface properties, their self-assembly in solution, and their interaction with macromolecules, such as proteins. Adsorption at the air-water and oil-water interfaces and solution self-assembly of the range of ethoxylated polysorbate surfactants synthesized are presented and discussed.

  14. In-situ x-ray absorption study of copper films in ground water solutions

    International Nuclear Information System (INIS)

    Kvashnina, K.O.; Butorin, S.M.; Modin, A.; Soroka, I.; Marcellini, M.; Nordgren, J.; Guo, J.-H.; Werme, L.

    2007-01-01

    This study illustrates how the damage from copper corrosion can be reduced by modifying the chemistry of the copper surface environment. The surface modification of oxidized copper films induced by chemical reaction with Cl - and HCO 3 - in aqueous solutions was monitored by in situ X-ray absorption spectroscopy. The results show that corrosion of copper can be significantly reduced by adding even a small amount of sodium bicarbonate. The studied copper films corroded quickly in chloride solutions, whereas the same solution containing 1.1 mM HCO 3 - prevented or slowed down the corrosion processes

  15. Fixed bed column study for Cu (II) removal from aqueous solution using water hyacinth (Eichornia crassipes) biomass.

    Science.gov (United States)

    Gandhimathi, R; Ramesh, S T; Yadu, Anubhav; Bharathi, K S

    2013-07-01

    This paper reports the results of the study on the performance of low-cost biosorbent water hyacinth (WH) in removing Cu (II) from aqueous solution. The adsorbent material adopted was found to be an efficient media for the removal of Cu (II) in continuous mode using fixed bed column. The column studies were conducted with 10 mg/L metal solution with a flow rate of 10 mL/min with different bed depths such as 10, 20 and 30 cm. The column design parameters like adsorption rate constant, adsorption capacity and minimum bed depth were calculated. It was found that, the adsorption capacity of copper ions by water hyacinth increased by increasing the bed depth and the contact time.

  16. Measurement of solute proton spin-lattice relaxation times in water using the 1,3,3,1 sequence

    International Nuclear Information System (INIS)

    Sankar, S.S.; Mole, P.A.; Coulson, R.L.

    1986-01-01

    1 H NMR spin-lattice relaxation times (T1) of the N-CH3 proton resonances of phosphocreatine (PCr) and creatine (Cr) in water solutions were obtained using the 1,3,3,1 pulse sequence. These T1 values were equivalent to those obtained in D 2 O and water using either the conventional inversion-recovery experiment or the 1,3,3,1 pulse sequence. Thus, the 1,3,3,1 sequence of proton NMR can provide an independent means along with phosphorous NMR for assess PCr and for the study of the creatine kinase reaction (PCr + ADP in equilibrium ATP + Cr) in aqueous solutions and perhaps in biological preparations

  17. X-ray CT-Derived Soil Characteristics Explain Varying Air, Water, and Solute Transport Properties across a Loamy Field

    DEFF Research Database (Denmark)

    Paradelo Pérez, Marcos; Katuwal, Sheela; Møldrup, Per

    2016-01-01

    -derived parameters by using a best subsets regression analysis. The regression coefficients improved using CTmatrix, limiting macroporosity, and genus density, while the best model for t0.05 used CTmatrix only. The scanning resolution and the time for soil structure development after mechanical activities could......The characterization of soil pore space geometry is important for explaining fluxes of air, water, and solutes through soil and understanding soil hydrogeochemical functions. X-ray computed tomography (CT) can be applied for this characterization, and in this study CT-derived parameters were used...... to explain water, air, and solute transport through soil. Forty-five soil columns (20 by 20 cm) were collected from an agricultural field in Estrup, Denmark, and subsequently scanned using a medical CT scanner. Nonreactive tracer leaching experiments were performed in the laboratory along with measurements...

  18. A numerical method for osmotic water flow and solute diffusion with deformable membrane boundaries in two spatial dimension

    Science.gov (United States)

    Yao, Lingxing; Mori, Yoichiro

    2017-12-01

    Osmotic forces and solute diffusion are increasingly seen as playing a fundamental role in cell movement. Here, we present a numerical method that allows for studying the interplay between diffusive, osmotic and mechanical effects. An osmotically active solute obeys a advection-diffusion equation in a region demarcated by a deformable membrane. The interfacial membrane allows transmembrane water flow which is determined by osmotic and mechanical pressure differences across the membrane. The numerical method is based on an immersed boundary method for fluid-structure interaction and a Cartesian grid embedded boundary method for the solute. We demonstrate our numerical algorithm with the test case of an osmotic engine, a recently proposed mechanism for cell propulsion.

  19. Effect of soaking in water and rumen digeta solutions on metabolizable energy content and chemical composition of barley seeds for use in poultry diet.

    Science.gov (United States)

    Tabatabee, S N; Sadeghi, G H; Tabeidian, S A

    2007-03-15

    An experiment was carried out to evaluate the effect of soaking in water and different rumen digesta solutions on nutritional value of dry barley seeds. Treatments were included distilled water as control and rumen digesta that diluted with distilled water to obtain 20, 40 and 60% digesta solutions. Solutions have added to 10 kg of barley seed samples to achieve final 30% moisture content. After 21 days the chemical composition and energy content of barley seed were determined. Gross energy of barley seeds did not affected by different experimental treatments. Use of 20% rumen digesta solution resulted to a significant (pcontent of barley seeds. Barley seed that treated with 40% of rumen digesta solution had highest TME and TMEn content and its different from seeds that treated with 60 and 100% rumen digesta solutions was significant (prumen digesta solutions increased crud protein, ether extract, crude fiber and ash content of barley seeds numerically.

  20. Partition coefficients of organics between water and carbon dioxide revisited: Correlation with solute molecular descriptors and solvent cohesive properties

    Czech Academy of Sciences Publication Activity Database

    Roth, Michal

    2016-01-01

    Roč. 50, č. 23 (2016), s. 12857-12863 ISSN 0013-936X R&D Projects: GA ČR(CZ) GA16-03749S Institutional support: RVO:68081715 Keywords : partitioning between water and supercritical CO2 * organic solutes * K-factor modeling * linear solvation energy relationship Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 6.198, year: 2016

  1. An expanded conceptual framework for solution-focused management of chemical pollution in European waters

    NARCIS (Netherlands)

    Munthe, John; Brorström-Lundén, Eva; Rahmberg, Magnus; Posthuma, Leo; Altenburger, Rolf; Brack, Werner; Bunke, Dirk; Engelen, Guy; Gawlik, Bernd Manfred; van Gils, Jos; Herráez, David López; Rydberg, Tomas; Slobodnik, Jaroslav; van Wezel, Annemarie

    2017-01-01

    Background: This paper describes a conceptual framework for solutions-focused management of chemical contaminants built on novel and systematic approaches for identifying, quantifying and reducing risks of these substances. Methods: The conceptual framework was developed in interaction with

  2. Process Analytical Technology in Freeze-Drying: Detection of the Secondary Solute + Water Crystallization with Heat Flux Sensors.

    Science.gov (United States)

    Wang, Qiming; Shalaev, Evgenyi

    2018-04-01

    In situ and non-invasive detection of solute crystallization during freeze-drying would facilitate cycle optimization and scale-up from the laboratory to commercial manufacturing scale. The objective of the study is to evaluate heat flux sensor (HFS) as a tool for monitoring solute crystallization and other first-order phase transitions (e.g., onset of freezing). HFS is a thin-film differential thermopile, which acts as a transducer to generate an electrical signal proportional to the total heat applied to its surface. In this study, HFS is used to detect both primary (ice formation) and secondary (also known as eutectic) solute + water crystallization during cooling and heating of solutions in a freeze-dryer. Binary water-solute mixtures with typical excipients concentrations (e.g., 0.9% of NaCl and 5% mannitol) and fill volumes (1 to 3 ml/vial) are studied. Secondary crystallization is detected by the HFS during cooling in all experiments with NaCl solutions, whereas timing of mannitol crystallization depends on the cooling conditions. In particular, mannitol crystallization takes place during cooling, if the cooling rate is lower than the critical value. On the other hand, if the cooling rate exceeds the critical cooling rate, mannitol crystallization during cooling is prevented, and crystallization occurs during subsequent warming or annealing. It is also observed that, while controlled ice nucleation allows initiation of the primary freezing event in different vials simultaneously, there is a noticeable vial-to-vial difference in the timing of secondary crystallization. The HFS could be a valuable process monitoring tool for non-invasive detection of various crystallization events during freeze-drying manufacturing.

  3. The Development and Full-Scale Experimental Validation of an Optimal Water Treatment Solution in Improving Chiller Performances

    Directory of Open Access Journals (Sweden)

    Chen-Yu Chiang

    2016-06-01

    Full Text Available An optimal solution, in combining physical and chemical water treatment methods, has been developed. This method uses a high voltage capacitance based (HVCB electrodes, coupled with biocides to form a sustainable solution in improving chiller plant performances. In this study, the industrial full-scale tests, instead of laboratory tests, have been conducted on chiller plants at the size of 5000 RT to 10,000 RT cooling capacities under commercial operation for more than two years. The experimental results indicated that the condenser approach temperatures can be maintained at below 1 °C for over two years. It has been validated that the coefficient of performance (COP of a chiller can be improved by over 5% by implementing this solution. Every 1 °C reduction in condenser approach temperature can yield approximately 3% increase on chiller COP, which warrants its future application potential in the HVAC industry, where Ta can degrade by 1 °C every three to six months. The solution developed in this study could also reduce chemical dosages and conserve makeup water substantially and is more environment friendly.

  4. Multi-model and multi-scenario assessments of Asian water futures: The Water Futures and Solutions (WFaS) initiative

    Science.gov (United States)

    Satoh, Yusuke; Kahil, Taher; Byers, Edward; Burek, Peter; Fischer, Günther; Tramberend, Sylvia; Greve, Peter; Flörke, Martina; Eisner, Stephanie; Hanasaki, Naota; Magnuszewski, Piotr; Nava, Luzma Fabiola; Cosgrove, William; Langan, Simon; Wada, Yoshihide

    2017-07-01

    This paper presents one of the first quantitative scenario assessments for future water supply and demand in Asia to 2050. The assessment, developed by the Water Futures and Solutions (WFaS) initiative, uses the latest set of global climate change and socioeconomic scenarios and state-of-the-art global hydrological models. In Asia, water demand for irrigation, industry, and households is projected to increase substantially in the coming decades (30-40% by 2050 compared to 2010). These changes are expected to exacerbate water stress, especially in the current hotspots such as north India and Pakistan, and north China. By 2050, 20% of the land area in the Asia-Pacific region, with a population of 1.6-2 billion, is projected to experience severe water stress. We find that socioeconomic changes are the main drivers of worsening water scarcity in Asia, with climate change impacts further increasing the challenge into the 21st century. Moreover, a detailed basin-level analysis of the hydro-economic conditions of 40 Asian basins shows that although the coping capacity of all basins is expected to improve due to gross domestic product (GDP) growth, some basins continuously face severe water challenges. These basins will potentially be home to up to 1.6 billion people by mid-21st century.

  5. Antimicrobial activity of copper against organisms in aqueous solution: a case for copper-based water pipelines in hospitals?

    Science.gov (United States)

    Cervantes, Hilda I; Alvarez, Jose A; Muñoz, Juan M; Arreguín, Virginia; Mosqueda, Juan L; Macías, Alejandro E

    2013-12-01

    An association exists between water of poor quality and health care-associated infections. Copper shows microbiocidal action on dry surfaces; it is necessary to evaluate its antimicrobial effect against organisms in aqueous solution. The objective was to determine the in vitro antimicrobial activity of copper against common nosocomial pathogens in aqueous solution. Copper and polyvinyl chloride containers were used. Glass was used as control material. Fourteen organisms isolated from hospital-acquired infections, and 3 control strains were tested. Inocula were prepared by direct suspension of colonies in saline solution and water in each container tested. Bacterial counts in colony-forming units (CFU)/mL were determined at the beginning of the experiment; at 30 minutes; and at 1, 2, 24, and 48 hours. Organisms in glass and polyvinyl chloride remained viable until the end of the experiment. Organisms in copper showed a reduction from more than 100,000 CFU/mL to 0 CFU/mL within the first 2 hours of contact (F > 4.29, P water for human use, particularly in hospitals. Copyright © 2013 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Mosby, Inc. All rights reserved.

  6. City-scale analysis of water-related energy identifies more cost-effective solutions.

    Science.gov (United States)

    Lam, Ka Leung; Kenway, Steven J; Lant, Paul A

    2017-02-01

    Energy and greenhouse gas management in urban water systems typically focus on optimising within the direct system boundary of water utilities that covers the centralised water supply and wastewater treatment systems, despite a greater energy influence by the water end use. This work develops a cost curve of water-related energy management options from a city perspective for a hypothetical Australian city. It is compared with that from the water utility perspective. The curves are based on 18 water-related energy management options that have been implemented or evaluated in Australia. In the studied scenario, the cost-effective energy saving potential from a city perspective (292 GWh/year) is far more significant than that from a utility perspective (65 GWh/year). In some cases, for similar capital cost, if regional water planners invested in end use options instead of utility options, a greater energy saving potential at a greater cost-effectiveness could be achieved in urban water systems. For example, upgrading a wastewater treatment plant for biogas recovery at a capital cost of $27.2 million would save 31 GWh/year with a marginal cost saving of $63/MWh, while solar hot water system rebates at a cost of $28.6 million would save 67 GWh/year with a marginal cost saving of $111/MWh. Options related to hot water use such as water-efficient shower heads, water-efficient clothes washers and solar hot water system rebates are among the most cost-effective city-scale opportunities. This study demonstrates the use of cost curves to compare both utility and end use options in a consistent framework. It also illustrates that focusing solely on managing the energy use within the utility would miss substantial non-utility water-related energy saving opportunities. There is a need to broaden the conventional scope of cost curve analysis to include water-related energy and greenhouse gas at the water end use, and to value their management from a city perspective. This

  7. Viability of human periodontal ligament fibroblasts in milk, Hank's balanced salt solution and coconut water as storage media.

    Science.gov (United States)

    Souza, B D M; Lückemeyer, D D; Reyes-Carmona, J F; Felippe, W T; Simões, C M O; Felippe, M C S

    2011-02-01

    To evaluate the effectiveness of various storage media at 5 °C for maintaining the viability of human periodontal ligament fibroblasts (PDLF). Plates with PDLF were soaked in recently prepared Hank's balanced salt solution (HBSS), skimmed milk, whole milk, Save-A-Tooth(®) system's HBSS (Save), natural coconut water, industrialized coconut water or tap water (negative control) at 5 °C for 3, 6, 24, 48, 72, 96 and 120 h. Minimum essential medium (MEM) at 37 °C served as the positive control. PDL cell viability was determined by MTT assay. Data were statistically analysed by Kruskal-Wallis test complemented by the Scheffé test (α=5%). The greatest number of viable cells was observed for MEM. Skimmed and whole milk, followed by natural coconut water and HBSS, were the most effective media in maintaining cell viability (Pmilk had the greatest capacity to maintain PDLF viability when compared with natural coconut water, HBSS, Save, industrialized coconut water and tap water. © 2010 International Endodontic Journal.

  8. Ice nucleation activity of silicates and aluminosilicates in pure water and aqueous solutions - Part 1: The K-feldspar microcline

    Science.gov (United States)

    Kumar, Anand; Marcolli, Claudia; Luo, Beiping; Peter, Thomas

    2018-05-01

    Potassium-containing feldspars (K-feldspars) have been considered as key mineral dusts for ice nucleation (IN) in mixed-phase clouds. To investigate the effect of solutes on their IN efficiency, we performed immersion freezing experiments with the K-feldspar microcline, which is highly IN active. Freezing of emulsified droplets with microcline suspended in aqueous solutions of NH3, (NH4)2SO4, NH4HSO4, NH4NO3, NH4Cl, Na2SO4, H2SO4, K2SO4 and KCl, with solute concentrations corresponding to water activities aw = 0.9-1.0, were investigated by means of a differential scanning calorimeter (DSC). The measured heterogeneous IN onset temperatures, Thet(aw), deviate strongly from ThetΔawhet(aw), the values calculated from the water-activity-based approach (where ThetΔawhet(aw) = Tmelt(aw + Δawhet) with a constant offset Δawhet with respect to the ice melting point curve). Surprisingly, for very dilute solutions of NH3 and NH4+ salts (molalities ≲1 mol kg-1 corresponding to aw ≳ 0.96), we find IN temperatures raised by up to 4.5 K above the onset freezing temperature of microcline in pure water (Thet(aw = 1)) and 5.5 K above ThetΔawhet(aw), revealing NH3 and NH4+ to significantly enhance the IN of the microcline surface. Conversely, more concentrated NH3 and NH4+ solutions show a depression of the onset temperature below ThetΔawhet(aw) by as much as 13.5 K caused by a decline in IN ability accompanied with a reduction in the volume fraction of water frozen heterogeneously. All salt solutions not containing NH4+ as cation exhibit nucleation temperatures Thet(aw) NH4+). However, the presence of a similar increase in IN efficiency in dilute ammonia solutions indicates that the cation exchange cannot explain the increase in IN temperatures. Instead, we hypothesize that NH3 molecules hydrogen bonded on the microcline surface form an ice-like overlayer, which provides hydrogen bonding favorable for ice to nucleate on, thus enhancing both the freezing temperatures and the

  9. How do glycerol and dimethyl sulphoxide affect local tetrahedral structure of water around a nonpolar solute at low temperature? Importance of preferential interaction

    Science.gov (United States)

    Daschakraborty, Snehasis

    2018-04-01

    Glycerol and dimethyl sulphoxide (DMSO) have vital roles in cryoprotection of living cells, tissues, etc. The above action has been directly linked with disruption of hydrogen (H-) bond structure and dynamics of water by these cosolvents at bulk region and around various complex units, such as peptide, amino acid, protein, and lipid membrane. However, the disruption of the local structure of the water solvent around a purely hydrophobic solute is still not studied extensively. The latter is also important in the context of stabilization of protein from cold denaturation. Through all-atom molecular dynamics simulation, we have investigated the comparative effect of glycerol and DMSO on the orientational order of water around a nonpolar solute at -5 °C. A steady reduction of the tetrahedral order of water is observed at bulk (>10 Å distance from the solute) and solute interface (structure of the interfacial water more than that of the bulk water, glycerol affects the water structure almost uniformly at all regions around the solute. Furthermore, while glycerol helps to retain water molecules at the interface, DMSO significantly reduces the water content in that region. We have put forward a plausible mechanism for these contrasting roles of these cosolvents. The solute-cosolvent hydrophobic-interaction-induced orientational alignment of an interfacial cosolvent molecule determines whether the involvement of the cosolvent molecules in H-bonding with solvent water in the interface is akin to the bulk region or not.

  10. Irrigation Water Quality for Leafy Crops: A Perspective of Risks and Potential Solutions

    Directory of Open Access Journals (Sweden)

    Ana Allende

    2015-07-01

    Full Text Available There is increasing evidence of the contribution of irrigation water in the contamination of produce leading to subsequent outbreaks of foodborne illness. This is a particular risk in the production of leafy vegetables that will be eaten raw without cooking. Retailers selling leafy vegetables are increasingly targeting zero-risk production systems and the associated requirements for irrigation water quality have become more stringent in regulations and quality assurance schemes (QAS followed by growers. Growers can identify water sources that are contaminated with potential pathogens through a monitoring regime and only use water free of pathogens, but the low prevalence of pathogens makes the use of faecal indicators, particularly E. coli, a more practical approach. Where growers have to utilise water sources of moderate quality, they can reduce the risk of contamination of the edible portion of the crop (i.e., the leaves by treating irrigation water before use through physical or chemical disinfection systems, or avoid contact between the leaves and irrigation water through the use of drip or furrow irrigation, or the use of hydroponic growing systems. This study gives an overview of the main problems in the production of leafy vegetables associated with irrigation water, including microbial risk and difficulties in water monitoring, compliance with evolving regulations and quality standards, and summarises the current alternatives available for growers to reduce microbial risks.

  11. Irrigation Water Quality for Leafy Crops: A Perspective of Risks and Potential Solutions

    Science.gov (United States)

    Allende, Ana; Monaghan, James

    2015-01-01

    There is increasing evidence of the contribution of irrigation water in the contamination of produce leading to subsequent outbreaks of foodborne illness. This is a particular risk in the production of leafy vegetables that will be eaten raw without cooking. Retailers selling leafy vegetables are increasingly targeting zero-risk production systems and the associated requirements for irrigation water quality have become more stringent in regulations and quality assurance schemes (QAS) followed by growers. Growers can identify water sources that are contaminated with potential pathogens through a monitoring regime and only use water free of pathogens, but the low prevalence of pathogens makes the use of faecal indicators, particularly E. coli, a more practical approach. Where growers have to utilise water sources of moderate quality, they can reduce the risk of contamination of the edible portion of the crop (i.e., the leaves) by treating irrigation water before use through physical or chemical disinfection systems, or avoid contact between the leaves and irrigation water through the use of drip or furrow irrigation, or the use of hydroponic growing systems. This study gives an overview of the main problems in the production of leafy vegetables associated with irrigation water, including microbial risk and difficulties in water monitoring, compliance with evolving regulations and quality standards, and summarises the current alternatives available for growers to reduce microbial risks. PMID:26151764

  12. Preconditions for market solution to urban water scarcity: Empirical results from Hyderabad City, India

    Science.gov (United States)

    Saleth, R. Maria; Dinar, Ariel

    2001-01-01

    Utilizing both primary and secondary information pertaining to the water sector of Hyderabad City, India, this paper (1) evaluates the economics of various technically feasible supply augmentations options; (2) estimates the group-specific water demand and consumption response functions under alternative pricing behaviors; (3) calculates the net willingness to pay (NWTP, considered to be the value of raw water at source) of different user groups as derived from their respective price elasticities; (4) shows how inadequate the NWTP is to justify most supply augmentation options including intersectoral water transfers under the existing water rate structure; (5) argues that the economic and institutional conditions internal to urban water sector cannot justify an externally imposed water transfers, whether market-based or otherwise, as long as the water rate structure is inefficient and regressive; and (6) concludes by underlining the central role that the pricing option, both the level and structure, plays not only in activating a number of nonprice options but also in generating incentives for the emergence of new and the consolidation of existing institutional conditions needed to support economically rooted water transfers and conservation initiatives.

  13. Irrigation Water Quality for Leafy Crops: A Perspective of Risks and Potential Solutions.

    Science.gov (United States)

    Allende, Ana; Monaghan, James

    2015-07-03

    There is increasing evidence of the contribution of irrigation water in the contamination of produce leading to subsequent outbreaks of foodborne illness. This is a particular risk in the production of leafy vegetables that will be eaten raw without cooking. Retailers selling leafy vegetables are increasingly targeting zero-risk production systems and the associated requirements for irrigation water quality have become more stringent in regulations and quality assurance schemes (QAS) followed by growers. Growers can identify water sources that are contaminated with potential pathogens through a monitoring regime and only use water free of pathogens, but the low prevalence of pathogens makes the use of faecal indicators, particularly E. coli, a more practical approach. Where growers have to utilise water sources of moderate quality, they can reduce the risk of contamination of the edible portion of the crop (i.e., the leaves) by treating irrigation water before use through physical or chemical disinfection systems, or avoid contact between the leaves and irrigation water through the use of drip or furrow irrigation, or the use of hydroponic growing systems. This study gives an overview of the main problems in the production of leafy vegetables associated with irrigation water, including microbial risk and difficulties in water monitoring, compliance with evolving regulations and quality standards, and summarises the current alternatives available for growers to reduce microbial risks.

  14. Oxygen and air nanobubble water solution promote the growth of plants, fishes, and mice.

    Directory of Open Access Journals (Sweden)

    Kosuke Ebina

    Full Text Available Nanobubbles (<200 nm in diameter have several unique properties such as long lifetime in liquid owing to its negatively charged surface, and its high gas solubility into the liquid owing to its high internal pressure. They are used in variety of fields including diagnostic aids and drug delivery, while there are no reports assessing their effects on the growth of lives. Nanobubbles of air or oxygen gas were generated using a nanobubble aerator (BUVITAS; Ligaric Company Limited, Osaka, Japan. Brassica campestris were cultured hydroponically for 4 weeks within air-nanobubble water or within normal water. Sweetfish (for 3 weeks and rainbow trout (for 6 weeks were kept either within air-nanobubble water or within normal water. Finally, 5 week-old male DBA1/J mice were bred with normal free-chaw and free-drinking either of oxygen-nanobubble water or of normal water for 12 weeks. Oxygen-nanobubble significantly increased the dissolved oxygen concentration of water as well as concentration/size of nanobubbles which were relatively stable for 70 days. Air-nanobubble water significantly promoted the height (19.1 vs. 16.7 cm; P<0.05, length of leaves (24.4 vs. 22.4 cm; P<0.01, and aerial fresh weight (27.3 vs. 20.3 g; P<0.01 of Brassica campestris compared to normal water. Total weight of sweetfish increased from 3.0 to 6.4 kg in normal water, whereas it increased from 3.0 to 10.2 kg in air-nanobubble water. In addition, total weight of rainbow trout increased from 50.0 to 129.5 kg in normal water, whereas it increased from 50.0 to 148.0 kg in air-nanobubble water. Free oral intake of oxygen-nanobubble water significantly promoted the weight (23.5 vs. 21.8 g; P<0.01 and the length (17.0 vs. 16.1 cm; P<0.001 of mice compared to that of normal water. We have demonstrated for the first time that oxygen and air-nanobubble water may be potentially effective tools for the growth of lives.

  15. Reactions of organic free radicals at colloidal silver in aqueous solution. Electron pool effect and water decomposition

    International Nuclear Information System (INIS)

    Henglein, A.

    1979-01-01

    Organic free radicals of high negative redox potential such as α-alcohol radicals were found to transfer electrons to colloidal silver particles stabilized by sodium dodecyl sulfate in aqueous solution. The colloidal particles thus became a pool of stored electrons that could reduce water to form hydrogen or react with suitable acceptors in solution. The organic radicals were produced by irradiation, using suitable scavengers for the primary radicals from the radiolysis of the aqueous solvent. The solutions initially contained silver ions at 1 x 10 -4 - 2 x 10 -3 M. At doses below 10 5 rd, the silver ions were completely reduced to form the colloidal catalyst. In this dose range, the corresponding hydrogen yield amounted to 1 molecule per 100 eV. It increased steeply at higher doses up to 3 molecules per 100 eV. The H 2 yield decreased with increasing dose rate and with increasing pH in alkaline solutions. It was highest at a concentration of sodium dodecyl sulfate of 1 x 10 -3 M, i.e., far below the critical micelle concentration of this surfactant. Changes in the absorption spectrum of the colloid are attributed to changes in the size of the silver particles upon charging up with electrons. The competition of radical-colloid reactions with radical-radical deactivation in the bulk of solution or at the surface of the colloidal particles is also discussed. 11 figures

  16. Thermodynamics of Highly Supersaturated Aqueous Solutions of Poorly Water-Soluble Drugs-Impact of a Second Drug on the Solution Phase Behavior and Implications for Combination Products.

    Science.gov (United States)

    Trasi, Niraj S; Taylor, Lynne S

    2015-08-01

    There is increasing interest in formulating combination products that contain two or more drugs. Furthermore, it is also common for different drug products to be taken simultaneously. This raises the possibility of interactions between different drugs that may impact formulation performance. For poorly water-soluble compounds, the supersaturation behavior may be a critical factor in determining the extent of oral absorption. The goal of the current study was to evaluate the maximum achievable supersaturation for several poorly water-soluble compounds alone, and in combination. Model compounds included ritonavir, lopinavir, paclitaxel, felodipine, and diclofenac. The "amorphous solubility" for the pure drugs was determined using different techniques and the change in this solubility was then measured in the presence of differing amounts of a second drug. The results showed that "amorphous solubility" of each component in aqueous solution is substantially decreased by the second component, as long as the two drugs are miscible in the amorphous state. A simple thermodynamic model could be used to predict the changes in solubility as a function of composition. This information is of great value when developing co-amorphous or other supersaturating formulations and should contribute to a broader understanding of drug-drug physicochemical interactions in in vitro assays as well as in the gastrointestinal tract. © 2015 Wiley Periodicals, Inc. and the American Pharmacists Association.

  17. The electric motor handbook

    Energy Technology Data Exchange (ETDEWEB)

    Hurst, R.W.; Feltham, P. (eds.)

    2004-05-01

    This handbook outlines the important role that electric motors play in modern society. It covers the field of motor applications from various motor types to their use and repair. It also presents practical applications of electric motors and methods on motor efficiency. More than half of all electricity generated, and 75 per cent of all industrial electricity consumption is consumed by electric motors. Electrical personnel must be aware of all factors involved in electric motors in order to choose and apply the appropriate size of electric motor. These factors include efficiency, sizing and proper application. The efficient use and maximum life expectancy of electric motors depends on proper motor protection, control and maintenance. This handbook includes articles from leading experts on electric motors in modern electrical systems. The content includes: design considerations; proper electric motor sizing techniques; optimal electric motor application; electric motor protection technology; electric motor control principles; electric motor maintenance and troubleshooting; induction electric motors; electric motor bearing currents; electric motor bearing lubrication; electromagnetism; electric motor enclosures; electric motor testing; electric motor repair; DC electric motor; electric motor starters; electric motor brushes; industrial electric motors; electric motor diagrams; AC electric motors; electric motor wiring; electric motor service; electric motor rewinding; electric motor winding; diagram of electric motor wiring; electric motor kit; and, troubleshooting electric motors. A directory of motor manufacturers and suppliers was also included. refs., tabs., figs.

  18. Response of three soil water sensors to variable solution electrical conductivity in different soils

    Science.gov (United States)

    Commercial dielectric soil water sensors may improve management of irrigated agriculture by providing continuous field soil water information. Use of these sensors is partly limited by sensor sensitivity to variations in soil salinity and texture, which force expensive, time consuming, soil specific...

  19. Acid and base recovery from brine solution using PVP intermediate-based bipolar membrane through water splitting technology

    Science.gov (United States)

    Venugopal, Krishnaveni; Murugappan, Minnoli; Dharmalingam, Sangeetha

    2017-07-01

    Potable water has become a scarce resource in many countries. In fact, the world is not running out of water, but rather, the relatively fixed quantity is becoming too contaminated for many applications. Hence, the present work was designed to evaluate the desalination efficiency of resin and glass fiber-reinforced Polysulfone polymer-based monopolar and bipolar (BPM) ion exchange membranes (with polyvinyl pyrrolidone as the intermediate layer) on a real sample brine solution for 8 h duration. The prepared ion exchange membranes (IEMs) were characterized using FTIR, SEM, TGA, water absorption, and contact angle measurements. The BPM efficiency, electrical conductivity, salinity, sodium, and chloride ion concentration were evaluated for both prepared and commercial-based IEM systems. The current efficiency and energy consumption values obtained during BPMED process were found to be 45 % and 0.41 Wh for RPSu-PVP-based IEM system and 38 % and 1.60 Wh for PSDVB-based IEM system, respectively.

  20. Retrieval of water cloud characteristic from active sensor data using the analytical solution of radiative transfer equation

    International Nuclear Information System (INIS)

    Cai, W.; Gayen, S.K.

    2010-01-01

    An analytical forward model and numerical algorithm for retrieving the parameters of water cloud of earth atmosphere from optical measurements carried out by satellite-based lidars is presented. The forward model, based on the analytical solution of the radiative transfer equation, is used to fit the temporal profile of the laser light pulses backscattered from the cloud layers. The cloud parameters extracted from the analysis at each position on earth include the transport mean free path, the average radius of water drops, the density of drops, the scattering length, the scattering cross section, the anisotropy factor, and the altitude of top level of major clouds. Also estimated is the possible thickness of cloud layers. The efficacy of the approach is demonstrated by generating parameters of water cloud using the data collected by NASA's cloud-aerosol lidar and infrared pathfinder satellite observations (CALIPSO) satellite when it passed through North America on August 7, 2007.

  1. Thermodynamics of micelle formation in a water-alcohol solution of sodium tetradecyl sulfate

    Science.gov (United States)

    Shilova, S. V.; Tret'yakova, A. Ya.; Barabanov, V. P.

    2016-01-01

    The effects of addition of ethanol and propan-1-ol on sodium tetradecyl sulfate micelle formation in an aqueous solution are studied via microprobe fluorescence microscopy and conductometry. The critical micelle concentration, quantitative characteristics of micelles, and thermodynamic parameters of micelle formation are determined. Addition of 5-15 vol % of ethanol or 5-10 vol % of propan-1-ol is shown to result in a lower critical micelle concentration than in the aqueous solution, and in the formation of mixed spherical micelles whose sizes and aggregation numbers are less than those for the systems without alcohol. The contribution from the enthalpy factor to the free energy of sodium tetradecyl sulfate micelle formation is found to dominate in mixed solvents, in contrast to aqueous solutions.

  2. Determination of the unfrozen water content of maximally freeze-concentrated carbohydrate solutions.

    Science.gov (United States)

    Hatley, R H; Mant, A

    1993-08-01

    The heat capacity change at T'g has been studied in freeze-concentrated carbohydrate solutions. The values obtained have been compared with those found for high concentration solutions that do not undergo freezing above Tg. The analysis has indicated that the freezing process influences the degree of stress in the glassy phase. This results in a complex power-time curve when frozen solutions are heated in a differential scanning calorimeter. The endotherm produced by the stress relaxation can cause considerable error in W'g measurement obtained by any method that relies on the integration of the power-time curve. A more reliable method for W'g determination is via the intersection of T'g with a previously prepared Tg/Wg calibration curve.

  3. Extraction of lanthanide(III) nitrates from water-salt solutions with n.-octanol

    International Nuclear Information System (INIS)

    Keskinov, V.A.; Kudrova, A.V.; Valueva, O.V.; Pyartman, A.K.

    2004-01-01

    Extraction of lanthanide(III) nitrates (Ln=La-Nd, Sm-Gd) from aqueous-salt solutions at 298.15 K was studied using solution of n.-octanol, its concentration 6.31 mol/l. It was ascertained that at Ln(NO 3 ) 3 concentration in aqueous phase below 0.6 mol/l, there is actually no extraction. At higher concentrations of nitrates in aqueous phase the content of lanthanides(III) in organic phase increases in the series La-Gd. Isotherms of extraction were ascertained, its phase equilibria being described mathematically. It is shown that extraction of lanthanide(III) nitrates with n.-octanol should be realized from concentrated aqueous solutions [ru

  4. Variable Step Integration Coupled with the Method of Characteristics Solution for Water-Hammer Analysis, A Case Study

    Science.gov (United States)

    Turpin, Jason B.

    2004-01-01

    One-dimensional water-hammer modeling involves the solution of two coupled non-linear hyperbolic partial differential equations (PDEs). These equations result from applying the principles of conservation of mass and momentum to flow through a pipe, and usually the assumption that the speed at which pressure waves propagate through the pipe is constant. In order to solve these equations for the interested quantities (i.e. pressures and flow rates), they must first be converted to a system of ordinary differential equations (ODEs) by either approximating the spatial derivative terms with numerical techniques or using the Method of Characteristics (MOC). The MOC approach is ideal in that no numerical approximation errors are introduced in converting the original system of PDEs into an equivalent system of ODEs. Unfortunately this resulting system of ODEs is bound by a time step constraint so that when integrating the equations the solution can only be obtained at fixed time intervals. If the fluid system to be modeled also contains dynamic components (i.e. components that are best modeled by a system of ODEs), it may be necessary to take extremely small time steps during certain points of the model simulation in order to achieve stability and/or accuracy in the solution. Coupled together, the fixed time step constraint invoked by the MOC, and the occasional need for extremely small time steps in order to obtain stability and/or accuracy, can greatly increase simulation run times. As one solution to this problem, a method for combining variable step integration (VSI) algorithms with the MOC was developed for modeling water-hammer in systems with highly dynamic components. A case study is presented in which reverse flow through a dual-flapper check valve introduces a water-hammer event. The predicted pressure responses upstream of the check-valve are compared with test data.

  5. Innovative solutions for intractable water problems in the face of climate change in southern and East African sub regions

    Science.gov (United States)

    Mapani, Benjamin; Makurira, Hodson; Magole, Lapologang; Meck, Maideyi; Mkandawire, Theresa; Mul, Marloes; Ngongondo, Cosmo

    2018-06-01

    This issue has a total of thirty-two (32) papers; and covers the IWRM sub themes of Hydrology, Land and People, Water Resources Management, Water and Environment and Wastewater and Sanitation. Water issues have become more and more complex as the supply side is affected by issues of quantity, availability and vulnerability due to natural factors such as climate change and urbanization. These challenges call for new management strategies and governance styles. Access to clean freshwater is a basic requirement for enhanced quality of life and development by all. However, this access has three main components that must be met adequately as this issue illustrates. These components are firstly, the quantity of water available; secondly, the quality and thirdly supply and appropriate delivery of this precious resource to domestic, commercial and industrial users. The demand side has also become more challenging, especially in urban areas as more and more people move from the rural areas to the cities. It has become a daily challenge in many African cities to supply water to these new urban dwellers and more so in unplanned settlements. These issues require a way and manner of delivering solutions and new innovative ideas. The topics in this issue vary from climate variability and how we are to improve our management strategies to mitigation, through to vulnerability of water resources and how to strengthen governance issues that plague some institutions in our region.

  6. Assessment of trace ground-water contaminants release from south Texas in-situ uranium solution-mining sites

    Energy Technology Data Exchange (ETDEWEB)

    Kidwell, J.R.; Humenick, M.J.

    1981-01-01

    The future of uranium solution mining in south Texas depends heavily on the industry's ability to restore production zone ground water to acceptable standards. This study investigated the extent of trace contaminant solubilization during mining and subsequent restoration attempts, first through a literature search centered on uranium control mechanisms, and then by laboratory experiments simulating the mining process. The literature search indicated the complexity of the situation. The number of possible interactions between indigenous elements and materials pointed on the site specificity of the problem. The column studies evaluated three different production area ores. Uranium, molybdenum, arsenic, vanadium, and selenium were analyzed in column effluents. After simulated mining operations were completed, uranium was found to be the most persistent trace element. However, subsequent ground water flushing of the columns could restore in-situ water to EPA recommended drinking water concentrations. Limited data indicated that ground water flowing through mined areas may solubilize molybdenum present in down gradient areas adjacent to the production zone due to increased oxidation potential of ground water if adequate restoration procedures are not followed.

  7. Low temperature hydrolysis of laboratory tholins in ammonia-water solutions: Implications for prebiotic chemistry on Titan

    Science.gov (United States)

    Neish, Catherine D.; Somogyi, Árpád; Lunine, Jonathan I.; Smith, Mark A.

    2009-05-01

    Laboratory tholins react rapidly in 13 wt% ammonia-water at low temperature, producing complex organic molecules containing both oxygen and altered nitrogen functional groups. These reactions display first-order kinetics with half-lives between 0.3 and 14 days at 253 K. The reaction timescales are much shorter than the freezing timescales of impact melts and volcanic sites on Titan, providing ample time for the formation of oxygenated, possibly prebiotic, molecules on its surface. Comparing the rates of the hydrolysis reactions in ammonia-water to those measured in pure water [Neish, C.D, Somogyi, A., Imanaka, H., Lunine, J.I., Smith, M.A., 2008a. Astrobiology 8, 273-287], we find that incorporation of oxygen into the tholins is faster in the presence of ammonia. The rate increases could be due to the increased pH of the solution, or to the availability of new reaction pathways made possible by the presence of ammonia. Using labeled 15NH 3 water, we find that ammonia does incorporate into some products, and that the reactions with ammonia are largely independent of those with water. A related study in HO18 confirms water as the source of the oxygen incorporated into the oxygen containing products.

  8. Forced intrusion of water and aqueous solutions in microporous materials: from fundamental thermodynamics to energy storage devices.

    Science.gov (United States)

    Fraux, Guillaume; Coudert, François-Xavier; Boutin, Anne; Fuchs, Alain H

    2017-12-07

    We review the high pressure forced intrusion studies of water in hydrophobic microporous materials such as zeolites and MOFs, a field of research that has emerged some 15 years ago and is now very active. Many of these studies are aimed at investigating the possibility of using these systems as energy storage devices. A series of all-silica zeolites (zeosil) frameworks were found suitable for reversible energy storage because of their stability with respect to hydrolysis after several water intrusion-extrusion cycles. Several microporous hydrophobic zeolite imidazolate frameworks (ZIFs) also happen to be quite stable and resistant towards hydrolysis and thus seem very promising for energy storage applications. Replacing pure water by electrolyte aqueous solutions enables to increase the stored energy by a factor close to 3, on account of the high pressure shift of the intrusion transition. In addition to the fact that aqueous solutions and microporous silica materials are environmental friendly, these systems are thus becoming increasingly interesting for the design of new energy storage devices. This review also addresses the theoretical approaches and molecular simulations performed in order to better understand the experimental behavior of nano-confined water. Molecular simulation studies showed that water condensation takes place through a genuine first-order phase transition, provided that the interconnected pores structure is 3-dimensional and sufficiently open. In an extreme confinement situations such as in ferrierite zeosil, condensation seem to take place through a continuous supercritical crossing from a diluted to a dense fluid, on account of the fact that the first-order transition line is shifted to higher pressure, and the confined water critical point is correlatively shifted to lower temperature. These molecular simulation studies suggest that the most important features of the intrusion/extrusion process can be understood in terms of equilibrium

  9. Application of Sargassum biomass to remove heavy metal ions from synthetic multi-metal solutions and urban storm water runoff.

    Science.gov (United States)

    Vijayaraghavan, K; Teo, Ting Ting; Balasubramanian, R; Joshi, Umid Man

    2009-05-30

    The ability of Sargassum sp. to biosorb four metal ions, namely lead, copper, zinc, and manganese from a synthetic multi-solute system and real storm water runoff has been investigated for the first time. Experiments on synthetic multi-solute systems revealed that Sargassum performed well in the biosorption of all four metal ions, with preference towards Pb, followed by Cu, Zn, and Mn. The solution pH strongly affected the metal biosorption, with pH 6 being identified as the optimal condition for achieving maximum biosorption. Experiments at different biosorbent dosages revealed that good biosorption capacity as well as high metal removal efficiency was observed at 3g/L. The biosorption kinetics was found to be fast with equilibrium being attained within 50 min. According to the Langmuir isotherm model, Sargassum exhibited maximum uptakes of 214, 67.5, 24.2 and 20.2mg/g for lead, copper, zinc, and manganese, respectively in single-solute systems. In multi-metal systems, strong competition between four metal ions in terms of occupancy binding sites was observed, and Sargassum showed preference in the order of Pb>Cu>Zn>Mn. The application of Sargassum to remove four heavy metal ions in real storm water runoff revealed that the biomass was capable of removing the heavy metal ions. However, the biosorption performance was slightly lower compared to that of synthetic metal solutions. Several factors were responsible for this difference, and the most important factor is the presence of other contaminants such as anions, organics, and other trace metals in the runoff.

  10. Hydro-economic modeling of integrated solutions for the water-energy-land nexus in Africa

    Science.gov (United States)

    Parkinson, S.; Kahil, M.; Wada, Y.; Krey, V.; Byers, E.; Johnson, N. A.; Burek, P.; Satoh, Y.; Willaarts, B.; Langan, S.; Riahi, K.

    2017-12-01

    This study focused on the development of the Extended Continental-scale Hydro-economic Optimization model (ECHO) and its application to the analysis of long-term water, energy and land use pathways for Africa. The framework is important because it integrates multi-decadal decisions surrounding investments into new water infrastructure, electric power generation and irrigation technologies. The improved linkages in ECHO reveal synergies between water allocation strategies across sectors and the greenhouse gas emissions resulting from electricity supply. The African case study features a reduced-form transboundary river network and associated environmental flow constraints covering surface and groundwater withdrawals. Interactions between local water constraints and the continental-scale economy are captured in the model through the combination of regional electricity markets. Spatially-explicit analysis of land availability is used to restrict future reservoir expansion. The analysis demonstrates the massive investments required to ensure rapidly expanding water, energy and food demands in Africa aligned with human development objectives are met in a sustainable way. Modeled constraints on environmental flows in line with presumptive ecological guidelines trigger diffusion of energy-intensive water supply technologies in water-stressed regions, with implications for the cost and speed of the electricity sector decarbonization required to achieve climate targets.

  11. On the Control of Solute Mass Fluxes and Concentrations Below Fields Irrigated With Low-Quality Water: A Numerical Study

    Science.gov (United States)

    Russo, David

    2017-11-01

    The main goal of this study was to test the capability of irrigation water-based and soil-based approaches to control nitrate and chloride mass fluxes and concentrations below the root zone of agricultural fields irrigated with treated waste water (TWW). Using numerical simulations of flow and transport in relatively a fine-textured, unsaturated, spatially heterogeneous, flow domain, scenarios examined include: (i) irrigating with TWW only (REF); (ii) irrigation water is substituted between TWW and desalinized water (ADW); (iii) soil includes a capillary barrier (CB) and irrigating with TWW only (CB + TWW); and (iv) combination of (ii) and a CB (CB + ADW). Considering groundwater quality protection, plausible goals are: (i) to minimize solute discharges leaving the root zone, and, (ii) to maximize the probability that solute concentrations leaving the root zone will not exceed a prescribed, critical value. Results of the analyses suggest that in the case of a seasonal crop (a corn field) subject to irrigations only, with respect to the first goal, the CB + TWW and CB + ADW scenarios provide similar, excellent results, better than the ADW scenario; with respect to the second goal, however, the CB + ADW scenario gave substantially better results than the CB + TWW scenario. In the case a multiyear, perennial crop (a citrus orchard), subject to a sequence of irrigation and rainfall periods, for both solutes, and, particularly, nitrate, with respect to the two goals, both the ADW and CB + ADW scenarios perform better than the CB + TWW scenario. As compared with the REF and CB + TWW scenarios, the ADW and CB + ADW scenarios substantially reduce nitrogen mass fluxes to the groundwater and to the atmosphere, and, essentially, did not reduce nitrogen mass fluxes to the trees. Similar results, even better, were demonstrated for a relatively coarse-textured, spatially heterogeneous soil.

  12. Investigation of factors affecting the stability of lysozyme spray dried from ethanol-water solutions

    DEFF Research Database (Denmark)

    Ji, Shuying; Thulstrup, Peter Waaben; Mu, Huiling

    2017-01-01

    -ethanol mixtures. The effect of formulation additives (trehalose, Tween 20 and phosphate-buffered saline) and processing conditions (inlet temperature and storage time of lysozyme in the feed solution before the spray drying process) on the protein bioactivity was investigated. The results showed...

  13. New Class of Solutions for Water Infiltration Problems in Unsaturated Soils

    DEFF Research Database (Denmark)

    Barari, Amin; Omidvar, M; Momeni, M

    2010-01-01

    This paper presents the results of approximate analytical solutions to Richards’ equation, which governs the problem of unsaturated flow in porous media. The existing methods generally fall within the category of numerical and analytical methods, often having many restrictions for practical situa...

  14. Approximate analytical solution to diurnal atmospheric boundary-layer growth under well-watered conditions

    Science.gov (United States)

    The system of governing equations of a simplified slab model of the uniformly-mixed, purely convective, diurnal atmospheric boundary layer (ABL) is shown to allow immediate solutions for the potential temperature and specific humidity as functions of the ABL height and net radiation when expressed i...

  15. Inhibition of localized attack on the aluminium alloy AA 6351 in glycol/water solutions

    Energy Technology Data Exchange (ETDEWEB)

    Monticelli, C; Brunoro, G; Zucchi, F; Fagioli, F

    1989-06-01

    The objective of this work was to examine the feasibility of enhancing pitting resistance of AA 6351 (nominal composition: 1% Si, 0.6% Mg, 0.3% Mn, balance Al) by adding suitable inhibitors to the solutions. The compounds used were two inorganic salts: sodium molybdate and sodium tungstate and two derivatives of pyrimidine: 2-aminopyrimidine (2AP) and 2-hydroxypyrimidine (2HP). The inhibiting efficiencies of these substances were tested by both short-time electrochemical tests (galvanic coupling tests and polarization curves) and long-time immersions under experimental conditions causing the localized attack. Molybdate, tungstate and, to some extent, also 2AP efficiently inhibit AA 6351 localized corrosion in degraded solutions at 80/sup 0/C and in pure boiling solutions, for long exposure periods. The short-time electrochemical tests suggest that molybdate and tungstate are able to retard the electrochemical processes occurring on both the aluminium alloy and the small copper cathodic area produced by copper deposition. On the other hand, the 2AP efficiency is attributed to some complexing capability of this pyrimidine derivative towards dissolved copper ions, that are stabilized in solution. 2HP does not prevent AA 6351 localized attack. (orig./MM).

  16. Review of Various Solutions for avoiding critical levels of Legionella Bacteria in Domestic Hot Water System

    DEFF Research Database (Denmark)

    Yang, Xiaochen; Li, Hongwei; Svendsen, Svend

    2013-01-01

    , electric boiler, compact heat exchanger, water filter, chlorine dioxide, Monochloramine, UV sterilization, copper and silver electrodes. The implementary conditions, effect, limits as well as economic performance of them are demonstrated. For buildings with complicated networks and large volume, chemical...

  17. Functional test of pedotransfer functions to predict water flow and solute transport with the dual-permeability model MACRO

    Directory of Open Access Journals (Sweden)

    J. Moeys

    2012-07-01

    Full Text Available Estimating pesticide leaching risks at the regional scale requires the ability to completely parameterise a pesticide fate model using only survey data, such as soil and land-use maps. Such parameterisations usually rely on a set of lookup tables and (pedotransfer functions, relating elementary soil and site properties to model parameters. The aim of this paper is to describe and test a complete set of parameter estimation algorithms developed for the pesticide fate model MACRO, which accounts for preferential flow in soil macropores. We used tracer monitoring data from 16 lysimeter studies, carried out in three European countries, to evaluate the ability of MACRO and this "blind parameterisation" scheme to reproduce measured solute leaching at the base of each lysimeter. We focused on the prediction of early tracer breakthrough due to preferential flow, because this is critical for pesticide leaching. We then calibrated a selected number of parameters in order to assess to what extent the prediction of water and solute leaching could be improved.

    Our results show that water flow was generally reasonably well predicted (median model efficiency, ME, of 0.42. Although the general pattern of solute leaching was reproduced well by the model, the overall model efficiency was low (median ME = −0.26 due to errors in the timing and magnitude of some peaks. Preferential solute leaching at early pore volumes was also systematically underestimated. Nonetheless, the ranking of soils according to solute loads at early pore volumes was reasonably well estimated (concordance correlation coefficient, CCC, between 0.54 and 0.72. Moreover, we also found that ignoring macropore flow leads to a significant deterioration in the ability of the model to reproduce the observed leaching pattern, and especially the early breakthrough in some soils. Finally, the calibration procedure showed that improving the estimation of solute transport parameters is

  18. Functional test of pedotransfer functions to predict water flow and solute transport with the dual-permeability model MACRO

    Science.gov (United States)

    Moeys, J.; Larsbo, M.; Bergström, L.; Brown, C. D.; Coquet, Y.; Jarvis, N. J.

    2012-07-01

    Estimating pesticide leaching risks at the regional scale requires the ability to completely parameterise a pesticide fate model using only survey data, such as soil and land-use maps. Such parameterisations usually rely on a set of lookup tables and (pedo)transfer functions, relating elementary soil and site properties to model parameters. The aim of this paper is to describe and test a complete set of parameter estimation algorithms developed for the pesticide fate model MACRO, which accounts for preferential flow in soil macropores. We used tracer monitoring data from 16 lysimeter studies, carried out in three European countries, to evaluate the ability of MACRO and this "blind parameterisation" scheme to reproduce measured solute leaching at the base of each lysimeter. We focused on the prediction of early tracer breakthrough due to preferential flow, because this is critical for pesticide leaching. We then calibrated a selected number of parameters in order to assess to what extent the prediction of water and solute leaching could be improved. Our results show that water flow was generally reasonably well predicted (median model efficiency, ME, of 0.42). Although the general pattern of solute leaching was reproduced well by the model, the overall model efficiency was low (median ME = -0.26) due to errors in the timing and magnitude of some peaks. Preferential solute leaching at early pore volumes was also systematically underestimated. Nonetheless, the ranking of soils according to solute loads at early pore volumes was reasonably well estimated (concordance correlation coefficient, CCC, between 0.54 and 0.72). Moreover, we also found that ignoring macropore flow leads to a significant deterioration in the ability of the model to reproduce the observed leaching pattern, and especially the early breakthrough in some soils. Finally, the calibration procedure showed that improving the estimation of solute transport parameters is probably more important than the

  19. On the hydrophilicity of polyzwitterion poly (N,N-dimethyl-N-(3-(methacrylamido)propyl)ammoniopropane sulfonate) in water, deuterated water, and aqueous salt solutions.

    Science.gov (United States)

    Hildebrand, Viet; Laschewsky, André; Zehm, Daniel

    2014-01-01

    A series of zwitterionic model polymers with defined molar masses up to 150,000 Da and defined end groups are prepared from sulfobetaine monomer N,N-dimethyl-N-(3-(methacrylamido)propyl)ammoniopropanesulfonate (SPP). Polymers are synthesized by reversible addition-fragmentation chain transfer polymerization (RAFT) using a functional chain transfer agent labeled with a fluorescent probe. Their upper critical solution temperature-type coil-to-globule phase transition in water, deuterated water, and various salt solutions is studied by turbidimetry. Cloud points increase with polyzwitterion concentration and molar mass, being considerably higher in D2O than in H2O. Moreover, cloud points are strongly affected by the amount and nature of added salts. Typically, they increase with increasing salt concentration up to a maximum value, whereas further addition of salt lowers the cloud points again, mostly down to below freezing point. The different salting-in and salting-out effects of the studied anions can be correlated with the Hofmeister series. In physiological sodium chloride solution and in phosphate buffered saline (PBS), the cloud point is suppressed even for high molar mass samples. Accordingly, SPP-polymers behave strongly hydrophilic under most conditions encountered in biomedical applications. However, the direct transfer of results from model studies in D2O, using, e.g. (1)H NMR or neutron scattering techniques, to 'normal' systems in H2O is not obvious.

  20. The European Pressurized Water Reactor. A safe and competitive solution for future energy needs

    International Nuclear Information System (INIS)

    Leverenz, R.; Gerhard, L.; Goebel, A.

    2004-01-01

    The European Pressurized Water Reactor - the EPR - is a PWR in the 1600 MW class. Its design is based on experience feedback from several thousand reactors x years of light water reactor operation worldwide, primarily those incorporating the most recent technologies: the French N4 and the German KONVOI reactors. It is an evolutionary design that ensures continuity in the mastery of PWR technology, minimizing the risk for the customer. (author)

  1. Stratigraphic controls on fluid and solute fluxes across the sediment-water interface of an estuary

    Science.gov (United States)

    Sawyer, Audrey H.; Lazareva, Olesya; Kroeger, Kevin D.; Crespo, Kyle; Chan, Clara S.; Stieglitz, Thomas; Michael, Holly A.

    2014-01-01

    Shallow stratigraphic features, such as infilled paleovalleys, modify fresh groundwater discharge to coastal waters and fluxes of saltwater and nutrients across the sediment–water interface. We quantify the spatial distribution of shallow surface water–groundwater exchange and nitrogen fluxes near a paleovalley in Indian River Bay, Delaware, using a hand resistivity probe, conventional seepage meters, and pore-water samples. In the interfluve (region outside the paleovalley) most nitrate-rich fresh groundwater discharges rapidly near the coast with little mixing of saline pore water, and nitrogen transport is largely conservative. In the peat-filled paleovalley, fresh groundwater discharge is negligible, and saltwater exchange is deep (∼1 m). Long pore-water residence times and abundant sulfate and organic matter promote sulfate reduction and ammonium production in shallow sediment. Reducing, iron-rich fresh groundwater beneath paleovalley peat discharges diffusely around paleovalley margins offshore. In this zone of diffuse fresh groundwater discharge, saltwater exchange and dispersion are enhanced, ammonium is produced in shallow sediments, and fluxes of ammonium to surface water are large. By modifying patterns of groundwater discharge and the nature of saltwater exchange in shallow sediments, paleovalleys and other stratigraphic features influence the geochemistry of discharging groundwater. Redox reactions near the sediment–water interface affect rates and patterns of geochemical fluxes to coastal surface waters. For example, at this site, more than 99% of the groundwater-borne nitrate flux to the Delaware Inland Bays occurs within the interfluve portion of the coastline, and more than 50% of the ammonium flux occurs at the paleovalley margin.

  2. Solution Properties of Water-Soluble “Smart” Poly(N-acryloyl-N′-ethyl piperazine-co-methyl methacrylate

    Directory of Open Access Journals (Sweden)

    G. Roshan Deen

    2012-01-01

    Full Text Available Water-soluble copolymers of N-acryloyl-N′-ethylpiperazine (AcrNEP with methyl methacrylate (MMA were synthesized to high conversion by free-radical solution polymerization. The composition of the copolymers was determined using Fourier Transform Infra-red Spectroscopy (FTIR. Copolymers containing AcrNEP content above 44 mol% were readily soluble in water and exhibited the critical solution temperature behavior. The copolymers were strongly responsive to changes in pH of the external medium due to the presence of tertiary amine functions that could be protonated at low pH. The influence of various factors such as copolymer composition, pH, temperature, salt and surfactant concentration on the LCST of the copolymers were systematically studied. The intrinsic viscosity of the copolymers in dimethyl formamide decreased with increase in temperature due to a decrease in thermodynamic affinity between polymer chains and solvent molecules. The viscosity behavior of the copolymers in sodium chloride solution was similar to that of classical polyelectrolytes and hydrophobically modified polyacrylate systems.

  3. Activity coefficients at infinite dilution measurements for organic solutes and water in the ionic liquid 1-ethyl-3-methylimidazolium tetracyanoborate

    International Nuclear Information System (INIS)

    Domanska, Urszula; Krolikowska, Marta; Acree, William E.; Baker, Gary A.

    2011-01-01

    Research highlights: → Measurements of activity coefficients at infinite dilution using GLC. → 36 organic solvents and water in the ionic liquid 1-ethyl-3-methylimidazolium tetracyanoborate, [EMIM][TCB]. → Possible entrainer for different separation processes. → The partial molar excess thermodynamic functions at infinite dilution were calculated. - Abstract: The activity coefficients at infinite dilution, γ 13 ∞ , for 36 solutes, including alkanes, cycloalkanes, alkenes, alkynes, aromatic hydrocarbons, alcohols, thiophene, tetrahydrofuran, ethers, acetone, and water, in the ionic liquid 1-ethyl-3-methylimidazolium tetracyanoborate, [EMIM][TCB], were determined by gas-liquid chromatography at temperatures from 298.15 K to 358.15 K. These values are compared to those previously published for selected solutes in the same ionic liquid. The values of the partial molar excess Gibbs free energy ΔG 1 E,∞ , enthalpy ΔH 1 E,∞ , and entropy ΔS 1 E,∞ at infinite dilution were calculated from the experimental γ 13 ∞ values obtained over the temperature range. Three gas-liquid partition coefficients, K L were calculated for all solutes and the Abraham solvation parameter model is discussed. The values of the selectivity for different separation problems were calculated from γ 13 ∞ and compared to literature values for N-methyl-2-pyrrolidinone (NMP), sulfolane, 1-decyl-3-methylimidazolium tetracyanoborate, [DMIM][TCB], and additional ionic liquids.

  4. Stable Isotope Analyses of water and Aqueous Solutions by Conventional Dual-inlet Mass Spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Horita, Juske [ORNL; Kendall, C. [U.S. Geological Survey, Menlo Park, CA

    2004-01-01

    The foundation of various analytical methods for the stable isotope composition of water and other aqueous samples (natural abundance, {sup 1}H : {sup 2}H (D) = 99.985 : 0.015 atom%, and {sup 16}O : {sup 17}O : {sup 18}O = 99.762 : 0.038 : 0.200 atom%) was established during the Manhatten Project in the U.S.A., when large amounts of heavy water were produced for nuclear reactors (see Kirshenbaum, 1951, for a detailed account). From early on, there was great interest in the oxygen and hydrogen isotopic compositions of water, because they are the ideal tracers of water sources and reactions. The increased analytical precisions made possible by the subsequent development of modern gas-source isotope-ratio mass spectrometers with dual-inlets and multi-collectors, have caused the proliferation of new analytical methods and applications for the oxygen and hydrogen isotopic compositions of water. These stable isotopes have found wide applications in basic as well as applied sciences (chemistry, geology, hydrology, biology, medical sciences, and food sciences). This is because water is ubiquitous, is an essential and predominant ingredient of living organisms, and is perhaps the most reactive compound in the Earth.

  5. Caution on the storage of waters and aqueous solutions in plastic containers for hydrogen and oxygen stable isotope analysis.

    Science.gov (United States)

    Spangenberg, Jorge E

    2012-11-30

    The choice of containers for storage of aqueous samples between their collection, transport and water hydrogen ((2)H) and oxygen ((18)O) stable isotope analysis is a topic of concern for a wide range of fields in environmental, geological, biomedical, food, and forensic sciences. The transport and separation of water molecules during water vapor or liquid uptake by sorption or solution and the diffusive transport of water molecules through organic polymer material by permeation or pervaporation may entail an isotopic fractionation. An experiment was conducted to evaluate the extent of such fractionation. Sixteen bottle-like containers of eleven different organic polymers, including low and high density polyethylene (LDPE and HDPE), polypropylene (PP), polycarbonate (PC), polyethylene terephthalate (PET), and perfluoroalkoxy-Teflon (PFA), of different wall thickness and size were completely filled with the same mineral water and stored for 659 days under the same conditions of temperature and humidity. Particular care was exercised to keep the bottles tightly closed and prevent loss of water vapor through the seals. Changes of up to +5‰ for δ(2)H values and +2.0‰ for δ(18)O values were measured for water after more than 1 year of storage within a plastic container, with the magnitude of change depending mainly on the type of organic polymer, wall thickness, and container size. The most important variations were measured for the PET and PC bottles. Waters stored in glass bottles with Polyseal™ cone-lined PP screw caps and thick-walled HDPE or PFA containers with linerless screw caps having an integrally molded inner sealing ring preserved their original δ(2)H and δ(18)O values. The carbon, hydrogen, and oxygen stable isotope compositions of the organic polymeric materials were also determined. The results of this study clearly show that for precise and accurate measurements of the water stable isotope composition in aqueous solutions, rigorous sampling and

  6. Discoloration and detoxicification of a Congo red dye solution by means of ozone treatment for a possible water reuse.

    Science.gov (United States)

    Khadhraoui, M; Trabelsi, H; Ksibi, M; Bouguerra, S; Elleuch, B

    2009-01-30

    The objective of this study was to investigate the degradation and mineralization of an azo-dye, the Congo red, in aqueous solutions using ozone. Phytotoxicity and the inhibitory effects on the microbial activity of the raw and the ozonated solutions were also carried out with the aim of water reuse and environment protection. Decolorization of the aqueous solutions, disappearance of the parent compound, chemical oxygen demand (COD) and total organic carbon (TOC) removal were the main parameters monitored in this study. To control the mineralization of the Congo red, pH of the ozonated solution and heteroatoms released from the mother molecule such NH(4)(+), NO(3)(-) and SO(4)(2-) were determined. It was concluded that ozone by itself is strong enough to decolorize these aqueous solutions in the early stage of the oxidation process. Nonetheless, efficient mineralization had not been achieved. Significant drops in COD (54%) were registered. The extent of TOC removal was about 32%. Sulfur heteroatom was totally oxidized to SO(4)(2-) ions while the central -NN- azo ring was partially converted to NH(4)(+) and NO(3)(-). Results of the kinetic studies showed that ozonation of the selected molecule was a pseudo-first-order reaction with respect to dye concentration. The obtained results also demonstrate that ozone process reduced the phytotoxicity of the raw solution and enhanced the biodegradability of the treated azo-dyes-wastewater. Hence, this show that ozone remains one of the effective technologies for the discoloration and the detoxification of organic dyes in wastewater.

  7. INFLUENCE OF QUARTZ CERAMICS SINGLE-STAGE PROCESSING BY GEL-FORMING WATER SOLUTIONS ON ITS STRENGTH

    Directory of Open Access Journals (Sweden)

    S. K. Evstropiev

    2014-09-01

    Full Text Available The main research results of the influence of quartz ceramics processing by silicon- and aluminum-containing gel- forming water solutions on its durability and porosity are given. Aqueous-alcoholic solutions based on tetraethoxysilane (TEOS, Si(C2H5O4 with additives of aluminum nitrate are proposed for impregnation of porous quartz ceramics samples. Ceramic samples are being impregnated with solutions at the room temperature for 12 minutes. After impregnation they are being exposed to drying at the room temperature for 24 hours and heat treatment in the electric muffle furnace. The made experiments show that impregnation of quartz ceramics porous samples by gel-forming solutions leads to durability growth of not burned samples by 6-7 times even without additional heat treatment. High-temperature heat treatment of previously impregnated ceramic samples leads to decomposition of aluminum nitrate and removal of fossils, and also to hardening of the formed additional bonds between material particles. It considerably improves strength characteristics of quartz ceramics as well. Thus, the possibility of considerable hardening of porous quartz ceramics and stability growth of its strength properties by preliminary impregnation of silicon- and aluminum-bearing gel-forming solutions even without additional heat treatment is experimentally shown. It is revealed that impregnation of porous quartz ceramic samples by these solutions leads only to insignificant reduction of porosity of samples. Subsequent heat treatment of the impregnated porous ceramic samples at the temperatures, equal to 900-1200oC, results in additional significant increase in their mechanical durability.

  8. Comparison of Temporal Profiles among Sucrose, Sucralose, and Acesulfame Potassium after Swallowing Sweetened Coffee Beverages and Sweetened Water Solutions

    Directory of Open Access Journals (Sweden)

    Naomi Gotow

    2018-04-01

    Full Text Available Non-nutritive sweeteners have been used as substitutes for nutritive sweeteners with the goal of preventing obesity and dental caries. The main factor responsible for the difference in taste between beverages containing a nutritive sweetener and those containing a non-nutritive sweetener is the temporal profile of sensory attributes. In this study, untrained panelists performed a time–intensity evaluation of sweetness, using one coffee beverage containing a nutritive sweetener (sucrose and two coffee beverages containing non-nutritive sweeteners (sucralose or acesulfame potassium (acesulfame K. They evaluated continuously perceived intensity of sweetness for 150 s after swallowing each coffee beverage. We did not detect a significant difference in temporal profiles among the three coffee beverages. To investigate why the temporal profiles of the three coffee beverages followed similar traces, all untrained participants who had participated in the coffee beverage session also performed a time–intensity evaluation of sweetness using three water solutions (sucrose-sweetened, sucralose-sweetened, and acesulfame K–sweetened deionized water. We observed a significant difference in temporal profiles among the three water solutions. These results indicate that differences in the temporal profiles of coffee beverages might be masked by factors other than the sweetness of the sweetener.

  9. Beta-adrenergic activation of solute coupled water uptake by toad skin epithelium results in near-isosmotic transport

    DEFF Research Database (Denmark)

    Nielsen, Robert; Larsen, Erik Hviid

    2007-01-01

    (V) with a [Na+] of the transported fluid of 130+/-24 mM ([Na+]Ringer's solution = 117.4 mM). Addition of bumetanide to the inside solution reduced J(V). Water was transported uphill and J(V) reversed at an excess outside osmotic concentration, deltaC(S,rev) = 28.9+/-3.9 mOsm, amiloride decreased delta......C(S,rev) to 7.5+/-1.5 mOsm. It is concluded that water uptake is accomplished by osmotic coupling in the lateral intercellular space (lis), and hypothesized that a small fraction of the Na+ flux pumped into lis is recirculated via basolateral NKCC transporters.......Transepithelial potential (V(T)), conductance (G(T)), and water flow (J(V)) were measured simultaneously with good time resolution (min) in isolated toad (Bufo bufo) skin epithelium with Ringer on both sides. Inside application of 5 microM isoproterenol resulted in the fast increase in G(T) from 1...

  10. Oxidizing dissolution of spent MOX47 fuel subjected to water radiolysis: Solution chemistry and surface characterization by Raman spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Jegou, C., E-mail: christophe.jegou@cea.f [Commissariat a l' Energie Atomique (CEA), Marcoule Reasearch Center, B.P. 17171, F-30207 Bagnols-sur-Ceze Cedex (France); Caraballo, R.; De Bonfils, J.; Broudic, V.; Peuget, S. [Commissariat a l' Energie Atomique (CEA), Marcoule Reasearch Center, B.P. 17171, F-30207 Bagnols-sur-Ceze Cedex (France); Vercouter, T. [Commissariat a l' Energie Atomique (CEA), Saclay Reasearch Center, B.P. 11, F-91191 Gif-sur-Yvette Cedex (France); Roudil, D. [Commissariat a l' Energie Atomique (CEA), Marcoule Reasearch Center, B.P. 17171, F-30207 Bagnols-sur-Ceze Cedex (France)

    2010-04-01

    The mechanisms of oxidizing dissolution of spent MOX fuel (MIMAS TU2 (registered) ) subjected to water radiolysis were investigated experimentally by leaching spent MOX47 fuel samples in pure water at 25 deg. C under different oxidizing conditions (with and without external gamma irradiation); the leached surfaces were characterized by Raman spectroscopy. The highly oxidizing conditions resulting from external gamma irradiation significantly increased the concentration of plutonium (Pu(V)) and uranium (U(VI)) compared with a benchmark experiment (without external irradiation). The oxidation behavior of the plutonium-enriched aggregates differed significantly from that of the UO{sub 2} matrix after several months of leaching in water under gamma irradiation. The plutonium in the aggregates appears to limit fuel oxidation. The only secondary phases formed and identified to date by Raman spectroscopy are uranium peroxides that generally precipitate on the surface of the UO{sub 2} grains. Concerning the behavior of plutonium, solution analysis results appear to be compatible with a conventional explanation based on an equilibrium with a Pu(OH){sub 4(am)} phase. The fission product release - considered as a general indicator of matrix alteration - from MOX47 fuel also increases under external gamma irradiation and a change in the leaching mode is observed. Diffusive leaching was clearly identified, coinciding with the rapid onset of steady-state actinide concentrations in the bulk solution.

  11. A Reconsideration of the Link between the Energetics of Water and of ATP Hydrolysis Energy in the Power Strokes of Molecular Motors in Protein Structures

    Directory of Open Access Journals (Sweden)

    Wilfred F. Widdas

    2008-09-01

    Full Text Available Mechanical energy from oxygen metabolism by mammalian tissues has been studied since 1837. The production of heat by mechanical work was studied by Fick in about 1860. Prior to Fick’s work, energetics were revised by Joule’s experiments which founded the First Law of Thermodynamics. Fenn in 1923/24 found that frog muscle contractions generated extra heat proportional to the amount of work done in shortening the muscle. This was fully consistent with the Joule, Helmholtz concept used for the First Law of Thermodynamics. The link between the energetics of water and ATP hydrolysis in molecular motors is recommended for reconsideration.

  12. A mathematical model for the transfer of soil solutes to runoff under water scouring.

    Science.gov (United States)

    Yang, Ting; Wang, Quanjiu; Wu, Laosheng; Zhang, Pengyu; Zhao, Guangxu; Liu, Yanli

    2016-11-01

    The transfer of nutrients from soil to runoff often causes unexpected pollution in water bodies. In this study, a mathematical model that relates to the detachment of soil particles by water flow and the degree of mixing between overland flow and soil nutrients was proposed. The model assumes that the mixing depth is an integral of average water flow depth, and it was evaluated by experiments with three water inflow rates to bare soil surfaces and to surfaces with eight treatments of different stone coverages. The model predicted outflow rates were compared with the experimentally observed data to test the accuracy of the infiltration parameters obtained by curve fitting the models to the data. Further analysis showed that the comprehensive mixing coefficient (ke) was linearly correlated with Reynolds' number Re (R(2)>0.9), and this relationship was verified by comparing the simulated potassium concentration and cumulative mass with observed data, respectively. The best performance with the bias error analysis (Nash Sutcliffe coefficient of efficiency (NS), relative error (RE) and the coefficient of determination (R(2))) showed that the predicted data by the proposed model was in good agreement with the measured data. Thus the model can be used to guide soil-water and fertilization management to minimize nutrient runoff from cropland. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. Water and solute transport in agricultural soils predicted by volumetric clay and silt contents

    DEFF Research Database (Denmark)

    Karup, Dan; Møldrup, Per; Paradelo Pérez, Marcos

    2016-01-01

    tracer mass could be well fitted to an analytical solution to the classical convection-dispersion equation. Both cumulative tracer mass and concentration as a function of time were hereby reasonable well predicted from the simple inputs of bulk density, clay and silt contents, and applied tracer mass......Solute transport through the soil matrix is heterogeneous and greatly affected by soil texture, soil structure, and macropore networks. This study examined the relationship between tracer breakthrough characteristics, soil hydraulic properties, and basic soil properties. Hundred...... of the soil structure rather than the actual formation of macropores causing preferential flow. The arrival times of 5 % and up to 50 % of the tracer mass were found to be strongly correlated with volumetric fines content. The hereby predicted tracer concentration breakthrough points up to 50% of applied...

  14. Modeling of water and solute transport under variably saturated conditions: state of the art

    International Nuclear Information System (INIS)

    Lappala, E.G.

    1980-01-01

    This paper reviews the equations used in deterministic models of mass and energy transport in variably saturated porous media. Analytic, quasi-analytic, and numerical solution methods to the nonlinear forms of transport equations are discussed with respect to their advantages and limitations. The factors that influence the selection of a modeling method are discussed in this paper; they include the following: (1) the degree of coupling required among the equations describing the transport of liquids, gases, solutes, and energy; (2) the inclusion of an advection term in the equations; (3) the existence of sharp fronts; (4) the degree of nonlinearity and hysteresis in the transport coefficients and boundary conditions; (5) the existence of complex boundaries; and (6) the availability and reliability of data required by the models

  15. Possibility of Modification of Zeolites by Iron Oxides and its Utilization for Removal of Pb(II from Water Solutions

    Directory of Open Access Journals (Sweden)

    Michal Lovás

    2004-12-01

    Full Text Available Ion-exchange properties of cations from lattice and ions from solutions are characteristic for zeolites. Zeolites as sorbents are used in many branches of industry. Ion-exchange reactions of cations on zeolites have been a theme of many works. With the exception of using natural zeolites as the sorbent, a modification of surface of zeolites and preparation of synthetic zeolites has received interest lately. One of the common modification of zeolites is modification by iron oxides, which increases capacity of adsorption. In this work, we prepared a modified zeolite by the precipitation of magnetite on the surface of zeolite. This new adsorbent was used to remove of Pb(II from waste water. The maximum adsorption capacity was 73,25 mg/g from the solution of Pb with the concentration of 400 mg/l.

  16. Prediction of non-polar gas solubilities in water, alcohols and aqueous alcohol solutions by the modified ASOG method

    Energy Technology Data Exchange (ETDEWEB)

    Tochigi, K.; Kojima, K.

    1982-07-01

    This study evaluated a technique for predicting gas solubilities based on a modified ASOG group-contribution method, considering water, alcohols, and aqueous alcohol solutions as the solvents. The nonpolar gaseous solutes considered were oxygen, nitrogen, hydrogen, carbon dioxide, argon, methane, ethane, ethylene, propane, and butane. Gas solubilities were correlated and predicted for a partial gas pressure of 1 atm and a temperature range of 50/sup 0/-100/sup 0/F (10/sup 0/-40/sup 0/C) in pure solvents, and then predicted for the same pressure and temperature range in mixed solvents using only the solubility data for the pure solvents. The deviations between the observed and predicted solubilities averaged 6.0% in pure systems and 10.2% in mixed solvents.

  17. Determination of boron in water solution by an indirect neutron activation technique from a 241Am/Be source

    International Nuclear Information System (INIS)

    Sales, H.B.

    1981-08-01

    Boron content in water solutions has been analysed by Indirect Activation Technique a twin 241 Am/Be neutron source with a source strength of 9x10 6 n/seg. The boron concentration was inferred from the measurement of the activity induced in a vanadium flux monitor. The vanadium rod was located inside the boron solution in a standart geometrical set up with respect to the neutron source. Boron concentrations in the range of 100 to 1000 ppm were determined with an overall accuracy of about 2% during a total analysis time of about 20 minutes. Eventhough the analysis is not selective for boron yet due the rapid, simple and precise nature, it is proposed for the analysis of boron in the primary coolant circuit of Nuclear Power Plants of PWR type. (Author) [pt

  18. Estruturação de cristais de gelo em soluções aquosas contendo solutos diversos Ice crystals structuring in water solutions containing different solutes

    Directory of Open Access Journals (Sweden)

    CLÉCIA SILVA CARNEIRO

    2000-02-01

    Full Text Available Existe uma grande demanda de conhecimentos na área de criopreservação de frutos tropicais com vistas a reduzir os danos celulares provocados por cristais de gelo durante o congelamento. O objetivo deste trabalho foi estudar a capacidade de estruturação de cristais de gelo. Soluções aquosas contendo arabinose, glicose, piridoxina, creatina, metionina, lisina e arginina, foram submetidas a congelamento lento em ar estático e as amostras resultantes examinadas por microscopia ótica sob luz polarizada. Os açúcares arabinose e glicose provocaram nos cristais de gelo estruturações que variaram de uma configuração hexagonal a uma arbórea, dentre outras. Vitaminas hidrossolúveis e compostos hidrofílicos ou hidrofóbicos favoreceram a formação de arranjamentos circulares filamentosos.There is a great demand for information about the cryopreservation of tropical fruits to reduce cell damage caused by ice crystals during freezing. The objective of this work was to study the structuring capacity of ice cristals. Water solutions having arabinose, glucose, pyridoxine, creatine, methionine, lysine and arginine were submitted to a slow freezing process and the resulting samples were examined under an optical microscope under polarized light. Sugars (arabinose and glucose caused a range of structures, from hexagonal to tree-like configurations, among others. Water soluble vitamins and hydrophilic or hydrophobic compounds favored the formation of needles arranged in a circular-type manner.

  19. Level Recession Of Emissions Release By Motor-And-Tractor Diesel Engines Through The Application Of Water-Fuel Emulsions

    Science.gov (United States)

    Ivanov, A.; Chikishev, E.

    2017-01-01

    The paper is dedicated to a problem of environmental pollution by emissions of hazardous substances with the exhaust gases of internal combustion engines. It is found that application of water-fuel emulsions yields the best results in diesels where production of a qualitative carburetion is the main problem for the organization of working process. During pilot studies the composition of a water-fuel emulsion with the patent held is developed. The developed composition of a water-fuel emulsion provides its stability within 14-18 months depending on mass content of components in it while stability of emulsions’ analogues makes 8-12 months. The mode of operation of pilot unit is described. Methodology and results of pilot study of operation of diesel engine on a water-fuel emulsion are presented. Cutting time of droplet combustion of a water-fuel emulsion improves combustion efficiency and reduces carbon deposition (varnish) on working surfaces. Partial dismantling of the engine after its operating time during 60 engine hours has shown that there is a removal of a carbon deposition in cylinder-piston group which can be observed visually. It is found that for steady operation of the diesel and ensuring decrease in level of emission of hazardous substances the water-fuel emulsion with water concentration of 18-20% is optimal.

  20. FURFURAL YIELD AND DECOMPOSITION IN SODIUM 2,4DIMETHYLBENZENESULFONATE--SULFURIC ACID--WATER SOLUTIONS.

    Science.gov (United States)

    Batch-type microreactors (about 1/40 milliliter of reactants) were used to measure furfural yields from acidified xylose solutions containing sodium...It was found that presence of the salt did not affect the quantity of furfural produced, but greatly increased the rate of formation. The regular...increase in rate of furfural formation was directly related to the increase in the rate xylose decomposition, and furfural yields for all salt and acid

  1. Estimates of water and solute release from a coal waste rock dump in the Elk Valley, British Columbia, Canada.

    Science.gov (United States)

    Villeneuve, S A; Barbour, S L; Hendry, M J; Carey, S K

    2017-12-01

    Long term (1999 to 2014) flow and water quality data from a rock drain located at the base of a coal waste rock dump constructed in the Elk Valley, British Columbia was used to characterize the release of three solutes (NO 3 - , Cl - and SO 4 2- ) from the dump and obtain whole dump estimates of net percolation (NP). The concentrations of dump derived solutes in the rock drain water were diluted by snowmelt waters from the adjacent natural watershed during the spring freshet and reached a maximum concentration during the winter baseflow period. Historical peak baseflow concentrations of conservative ions (NO 3 - and Cl - ) increased until 2006/07 after which they decreased. This decrease was attributed to completion of the flushing of the first pore volume of water stored within the dump. The baseflow SO 4 2- concentrations increased proportionally with NO 3 - and Cl - to 2007, but then continued to slowly increase as NO 3 - and Cl - concentrations decreased. This was attributed to ongoing production of SO 4 2- due to oxidation of sulfide minerals within the dump. Based on partitioning of the annual volume of water discharged from the rock drain to waste rock effluent (NP) and water entering the rock drain laterally from the natural watershed, the mean NP values were estimated to be 446±50mm/a (area normalized net percolation/year) for the dump and 172±71mm/a for the natural watershed. The difference was attributed to greater rates of recharge in the dump from summer precipitation compared to the natural watershed where rainfall interception and enhanced evapotranspiration will increase water losses. These estimates included water moving through subsurface pathways. However, given the limitations in quantifying these flows the estimated NP rates for both the natural watershed and the waste rock dump are considered to be low, and could be much higher (e.g. ~450mm/a and ~800mm/a). Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Motor homopolar

    OpenAIRE

    Martín Muñoz, Agustín

    2007-01-01

    Mostramos la construcción de un modelo de motor homopolar, uno de los más antiguos tipos de motores eléctricos. Se caracterizan porque el campo magnético del imán mantiene siempre la misma polaridad (de ahí su nombre, del griego homos, igual), de modo que, cuando una corriente eléctrica atraviesa el campo magnético, aparece una fuerza que hace girar los elementos no fijados mecánicamente. En el sencillísimo motor homopolar colgado (Schlichting y Ucke 2004), el imán puede girar ...

  3. THE SOLUTION TO THE PROBLEM OF USING GROUND WATER TO COOL LIVESTOCK BUILDINGS

    Directory of Open Access Journals (Sweden)

    Thay Ngok Shon

    2017-01-01

    Full Text Available Ambient temperature in the central part of Vietnam in summer can reach 32–35°C; in some places it can be more than 42°C. Hot climate strongly affects the animal organism alongside with the animal weight reduction and reduction the quantity of egg-laying in poultry. Therefore, air conditioning in livestock buildings is necessary. There are several ways to cool the temperature in such buildings, and each one has its own advantages and disadvantages. We propose to use underground water at the temperature of 24–25°C for this purpose. One of the methods of cooling sheds for livestock is sprinkler irrigation of water on the roof. For calculating the amount of heat, removed from the indoor air in the shed to the cooling water, in the first approximation specialists believe in some cases that an appropriate amount of heat being removed is determined mainly by heat transfer from the air inside the shed to the cooling water through the surface of the roof, represented by the lower part of the wave that form the surface of a metal tile, neglecting the influence of heat conduction on top of the wave of the tile surface. Consequentially, such a simplification leads to possible errors. Therefore, the authors solved the problem of cooling shed by irrigation of water on the roof by an analytical method. Specifically, we solved the problem of heat conductivity of the fin of the finite length of constant cross section, wherein different sides of the fin are conjugate with different environments. Additionally, the calculation considered the effect of solar radiation. For this purpose, the authors have created a heat balance equation at steady state for any infinitesimal element of the fin, and solved the differential equation afterwards. The authors applied the results for calculating practical problem of ground water irrigation of a roof of a livestock shed made of metal areas tiles. 

  4. Investigation of water content in electrolyte solution on electrochromic properties of WO3 thin Films

    Directory of Open Access Journals (Sweden)

    Zahra Abadi

    2017-05-01

    Full Text Available Tungsten oxide thin films were prepared by a cathodic electrodeposition method at -0.450 mV in order to investigate how water content affects their electrochromic properties. FESEM images exhibit that WO3 thin films consist of 65 nm uniform grains. Thin Films were electrochemically investigated in 0.1M LiClO4 in propylene carbonate electrolyte with and without 5vol% water content by cyclic voltammetry and chronoamperometry. The results indicate that tungsten oxide thin films exhibit faster switching time between coloration and bleaching states and also higher coloration efficiency in hydrated electrolyte.  

  5. Treatment of Fukushima contaminated waters TEPCO selected Areva and Veolia solution

    International Nuclear Information System (INIS)

    Seberac, Philippe; Paillard, Herve; Thierry, Jean-Marie; Bae, Ho-Il; Prevost, Thierry; Piot, Gregoire; Bertrand Ytournel

    2012-09-01

    The Actiflo-Rad TM system successfully contributed to treat the contaminated wastewaters from the damaged Fukushima Daiichi nuclear power plant. The decontamination system jointly designed by AREVA and Veolia Water treated about 77 500 m 3 of high activity wastewater (∼10 6 Bq/cm 3 ), combining radionuclides adsorbents developed by AREVA and the know-how of Veolia in water treatment for the settlement of the adsorbed radioactive elements, producing sludge with a weight concentration of 80 g/L. Both companies delivered the treatment facility quickly with an efficient joint organization - in a very complex environment. Assembled on Fukushima site - badly damaged by the tsunami following the earthquake of March 11 th - the system was designed, built and started in a record time of 2 month 1 / 2 , instead of several years in a classical nuclear engineering project. The Actiflo-Rad TM was a key equipment to achieve a stable situation of reactors, allowing treated water to be reused for core cooling. Commissioned with the on-site support of Veolia experts, the system reduced by 10 000 the Cs-activity of the wastewater even with significant salt content (seawater diluted twice) at a flow-rate slightly below the design value of 50 m 3 /hr. The implemented technologies are already used separately on AREVA sites (la Hague, fuel reprocessing plant) and for many water treatment projects by Veolia all over the world (Actiflo TM and Multiflo TM processes, using lamellar settling devices - in addition, the first one making use of micro-sand for a better floc quality). The complete treatment process selected by TEPCO features a physico-chemical treatment and water desalination, in five steps. After de-oiling, wastewater is primarily decontaminated through zeolite columns (Kurion process). This pre-decontaminated water is then treated on the AREVA-Veolia two stages system; at each stage, more than 30 minutes contact time with radionuclides adsorbents is needed, adsorbed

  6. Blow-up of solutions to the rotation b-family system modeling equatorial water waves

    Directory of Open Access Journals (Sweden)

    Min Zhu

    2018-03-01

    Full Text Available We consider the blow-up mechanism to the periodic generalized rotation b-family system (R-b-family system. This model can be derived from the f-plane governing equations for the geographical water waves with a constant underlying current in the equatorial water waves with effect of the Coriolis force. When b=2, it is a rotation two-component Camassa-Holm (R2CH system. We consider the periodic R2CH system when linear dispersion is absent (which model is called r2CH system and derive two finite-time blow-up results.

  7. A solution to the water resources crisis in wetlands: development of a scenario-based modeling approach with uncertain features.

    Science.gov (United States)

    Lv, Ying; Huang, Guohe; Sun, Wei

    2013-01-01

    A scenario-based interval two-phase fuzzy programming (SITF) method was developed for water resources planning in a wetland ecosystem. The SITF approach incorporates two-phase fuzzy programming, interval mathematical programming, and scenario analysis within a general framework. It can tackle fuzzy and interval uncertainties in terms of cost coefficients, resources availabilities, water demands, hydrological conditions and other parameters within a multi-source supply and multi-sector consumption context. The SITF method has the advantage in effectively improving the membership degrees of the system objective and all fuzzy constraints, so that both higher satisfactory grade of the objective and more efficient utilization of system resources can be guaranteed. Under the systematic consideration of water demands by the ecosystem, the SITF method was successfully applied to Baiyangdian Lake, which is the largest wetland in North China. Multi-source supplies (including the inter-basin water sources of Yuecheng Reservoir and Yellow River), and multiple water users (including agricultural, industrial and domestic sectors) were taken into account. The results indicated that, the SITF approach would generate useful solutions to identify long-term water allocation and transfer schemes under multiple economic, environmental, ecological, and system-security targets. It can address a comparative analysis for the system satisfactory degrees of decisions under various policy scenarios. Moreover, it is of significance to quantify the relationship between hydrological change and human activities, such that a scheme on ecologically sustainable water supply to Baiyangdian Lake can be achieved. Copyright © 2012 Elsevier B.V. All rights reserved.

  8. 33 CFR 127.1311 - Motor vehicles.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Motor vehicles. 127.1311 Section... Waterfront Facilities Handling Liquefied Hazardous Gas Operations § 127.1311 Motor vehicles. (a) When LHG is... operator shall ensure that no person— (1) Stops or parks a motor vehicle in a space other than a designated...

  9. The Interaction between Zein and Lecithin in Ethanol-Water Solution and Characterization of Zein?Lecithin Composite Colloidal Nanoparticles

    OpenAIRE

    Dai, Lei; Sun, Cuixia; Wang, Di; Gao, Yanxiang

    2016-01-01

    Lecithin, a naturally small molecular surfactant, which is widely used in the food industry, can delay aging, enhance memory, prevent and treat diabetes. The interaction between zein and soy lecithin with different mass ratios (20:1, 10:1, 5:1, 3:1, 2:1, 1:1 and 1:2) in ethanol-water solution and characterisation of zein and lecithin composite colloidal nanoparticles prepared by antisolvent co-precipitation method were investigated. The mean size of zein-lecithin composite colloidal nanoparti...

  10. Dissolution enthalpy of sodium sulfacetamide in water: comparison between solution isoperibolic calorimetry and the van't Hoff method

    OpenAIRE

    Torres, Daniel R.; Sosnik, Alejandro; Chiappetta, Diego; Vargas, Edgar F.; Martínez, Fleming

    2008-01-01

    The dissolution enthalpy (ΔH0soln) of sodium sulfacetamide in water was determined by means of isoperibolic solution calorimetry. It was found that ΔH0soln diminishes as the drug concentration increases. Otherwise, the calorimetric values obtained as a function of the drug concentration were significantly different than those predicted by the van't Hoff method. It was demonstrated that the later is not a fully reliable method for the determination of ΔH0soln values in the speci...

  11. A salt water battery with high stability and charging rates made from solution processed conjugated polymers with polar side chains

    OpenAIRE

    Moia, Davide; Giovannitti, Alexander; Szumska, Anna A.; Schnurr, Martin; Rezasoltani, Elham; Maria, Iuliana P.; Barnes, Piers R. F.; McCulloch, Iain; Nelson, Jenny

    2017-01-01

    We report a neutral salt water based battery which uses p-type and n-type solution processed polymer films as the cathode and the anode of the cell. The specific capacity of the electrodes (approximately 30 mAh cm-3) is achieved via formation of bipolarons in both the p-type and n-type polymers. By engineering ethylene glycol and zwitterion based side chains attached to the polymer backbone we facilitate rapid ion transport through the non-porous polymer films. This, combined with efficient t...

  12. Studies of mechanism of radioactive cesium-134 adsorption from water solutions onto tri ammonium dodecamolybdenophosphate(V)

    International Nuclear Information System (INIS)

    Choma, J.; Stasiuk, J.

    1992-01-01

    A mechanism of radioactive cesium-134 adsorption from water solutions on new, inorganic adsorbent composed from 85% of tri ammonium dodecamolibdophosphate(V) and 15% of urea resin is presented. A migration is found of Cs cations into the adsorbent grains. The absorption of Cs-134 beta radiation is studied as a function of WMF-15 tablet thickness. The penetration depth of radionuclide was found to be function of the process duration and the adsorbent density. Diffusion of cesium into the adsorbent grains explains the effect of ''recreation'' of its adsorption capacitance. (author). 2 refs, 2 figs

  13. Penetration of protective gloves as a route of intake for tritiated water and 125I-labelled sodium iodine solution

    International Nuclear Information System (INIS)

    Harris, S.J.; Gilmore, A.

    1980-01-01

    Measurements have been made of the rate at which tritiated water and 125 I-labelled sodium iodide solution penetrate various types of protective gloves, both isotopes being in common use in this form in universities and similar establishments. Diffusion coefficients relating to the glove materials are also determined. The health physics aspects are discussed and it is concluded that intakes by workers through intact gloves are not likely to be of major significance and can easily be minimised by the correct use and choice of glove. (author)