WorldWideScience

Sample records for treat light water

  1. Light & Water

    Directory of Open Access Journals (Sweden)

    Óscar Natividad Puig

    2013-06-01

    Full Text Available The proposal explores the Caos Theories, specifically, how applicable they are on local architectural interventions. It compiles a short study about possible variations of a same piece, in order to create difeerent ruled surfaces. Those pieces are distributed around a fractal attractor. The cores of these attractors are the ones responsible of collecting all the water flowing through the system. Once built, the project will enclose an open but covered space. Within this space, many different activities can be embraced, which allows its adaptability to each community where it?s placed. An open market will be the most common use though. It will allow selling agricultural products developed among the same community. Products irrigated with the extra water source collected by the cores of the fractal attractors.

  2. Light water reactor safety

    CERN Document Server

    Pershagen, B

    2013-01-01

    This book describes the principles and practices of reactor safety as applied to the design, regulation and operation of light water reactors, combining a historical approach with an up-to-date account of the safety, technology and operating experience of both pressurized water reactors and boiling water reactors. The introductory chapters set out the basic facts upon which the safety of light water reactors depend. The central section is devoted to the methods and results of safety analysis. The accidents at Three Mile Island and Chernobyl are reviewed and their implications for light wate

  3. Light water lattices

    International Nuclear Information System (INIS)

    1962-01-01

    The panel was attended by prominent physicists from most of the well-known laboratories in the field of light-water lattices, who exchanged the latest information on the status of work in their countries and discussed both the theoretical and the experimental aspects of the subjects. The supporting papers covered most problems, including criticality, resonance absorption, thermal utilization, spectrum calculations and the physics of plutonium bearing systems. Refs, figs and tabs

  4. Method of treating waste water

    Science.gov (United States)

    Deininger, James P.; Chatfield, Linda K.

    1995-01-01

    A process of treating water to remove metal ion contaminants contained therein, said metal ion contaminants selected from the group consisting of metals in Groups 8, 1b, 2b, 4a, 5a, or 6a of the periodic table, lanthanide metals, and actinide metals including transuranic element metals, by adjusting the pH of a metal ion contaminant-containing water source to within the range of about 6.5 to about 14.0, admixing the water source with a mixture of an alkali or alkaline earth ferrate and a water soluble salt, e.g., a zirconium salt, in an amount sufficient to form a precipitate within the water source, the amount the mixture of ferrate and water soluble salt effective to reduce the metal ion contaminant concentration in the water source, permitting the precipitate in the admixture to separate and thereby yield a supernatant liquid having a reduced metal ion contaminant concentration, and separating the supernatant liquid having the reduced metal ion contaminant concentration from the admixture is provided. A composition of matter including an alkali or alkaline earth ferrate and a water soluble salt, e.g., a zirconium salt, is also provided.

  5. Treating water-reactive wastes

    International Nuclear Information System (INIS)

    Lussiez, G.W.

    1993-01-01

    Some compounds and elements, such as lithium hydride, magnesium, sodium, and calcium react violently with water to generate much heat and produce hydrogen. The hydrogen can ignite or even form an explosive mixture with air. Other metals may react rapidly only if they are finely divided. Some of the waste produced at Los Alamos National Laboratory includes these metals that are contaminated with radioactivity. By far the greatest volume of water-reactive waste is lithium hydride contaminated with depleted uranium. Reactivity of the water-reactive wastes is neutralized with an atmosphere of humid nitrogen, which prevents the formation of an explosive mixture of hydrogen and air. When we adjust the temperature of the nitrogen and the humidifier, the nitrogen can be more or less humid, and the rate of reaction can be adjusted and controlled. Los Alamos has investigated the rates of reaction of lithium hydride as a function of the temperature and humidity, and, as anticipated, they in with in temperature and humidity. Los Alamos will investigate other variables. For example, the nitrogen flow will be optimized to conserve nitrogen and yet keep the reaction rates high. Reaction rates will be determined for various forms of lithium waste, from small chips to powder. Bench work will lead to the design of a skid-mounted process for treating wastes. Other water-reactive wastes will also be investigated

  6. Effect of water treated and urea treated neem ( Azadirachta indica ...

    African Journals Online (AJOL)

    In a study to evaluate the carcass haematological and biochemical characteristics of broiler birds fed graded levels of water and urea-treated neem kernel cake (NKC), 300 day-old broilers (Cobb, 500) were randomly assigned to five dietary treatments for 56 days. Water and feed were fed adlibitum. The diets were ...

  7. Neutron thermalization in light water

    International Nuclear Information System (INIS)

    Abbate, M.J.; Lolich, J.V.

    1975-05-01

    Investigations related to neutron thermalization in light water have been made. Neutron spectra under quasi-infinite-medium conditions have been measured by the time-of-flight technique and calculations were performed with different codes. Through the use of improved experimental techniques and the best known calculational techniques available, the known discrepancies between experimentals and theoretical values were below from 40% to 16%. The present disagreement is believed to be due the scattering model used (ENDF-GASKET, based on the modified Haywood II frequency spectra), that shows to be very satisfactory for poisoned light water cases. Moreover, previous experiments were completed and differential, integral and pulse-source experimental techniques were improved. Also a second step of a neutron and reactor calculation system was completed. (author)

  8. LIGHT WATER MODERATED NEUTRONIC REACTOR

    Science.gov (United States)

    Christy, R.F.; Weinberg, A.M.

    1957-09-17

    A uranium fuel reactor designed to utilize light water as a moderator is described. The reactor core is in a tank at the bottom of a substantially cylindrical cross-section pit, the core being supported by an apertured grid member and comprised of hexagonal tubes each containing a pluralily of fuel rods held in a geometrical arrangement between end caps of the tubes. The end caps are apertured to permit passage of the coolant water through the tubes and the fuel elements are aluminum clad to prevent corrosion. The tubes are hexagonally arranged in the center of the tank providing an amulus between the core and tank wall which is filled with water to serve as a reflector. In use, the entire pit and tank are filled with water in which is circulated during operation by coming in at the bottom of the tank, passing upwardly through the grid member and fuel tubes and carried off near the top of the pit, thereby picking up the heat generated by the fuel elements during the fission thereof. With this particular design the light water coolant can also be used as the moderator when the uranium is enriched by fissionable isotope to an abundance of U/sup 235/ between 0.78% and 2%.

  9. Advanced light water reactor plant

    International Nuclear Information System (INIS)

    Giedraityte, Zivile

    2008-01-01

    For nuclear power to be competitive with the other methods of electrical power generation the economic performance should be significantly improved by increasing the time spent on line generating electricity relative to time spent off-line conducting maintenance and refueling. Maintenance includes planned actions (surveillances) and unplanned actions (corrective maintenance) to respond to component degradation or failure. A methodology is described which is used to resolve maintenance related operating cycle length barriers. Advanced light water nuclear power plant is designed with the purpose to maximize online generating time by increasing operating cycle length. (author)

  10. Light-water reactor research and development

    International Nuclear Information System (INIS)

    1985-05-01

    This report on the national program of research and development on light water reactors is the second of two reports requested in 1982 by W. Kenneth Davis, Deputy Secretary of the Department of Energy. A first report, published in September 1983, treated the needs for safety-related R and D. In this second report, the Energy Research Advisory Board finds that, although many light water reactors are providing reliable and economic electricity, it appears unlikely that U.S. utilities will order additional reactors until the currently unacceptable economic risk, created by the regulatory climate and uncertain demand, is reduced. Thus it is unlikely that the private sector alone will fund major LWR design improvements. However, nuclear power will continue on its current course of expansion overseas. DOE participation is vitally needed to support the national interest in LWR technology. The report outlines R and D needs for a program to improve the safety, reliability, and economics of the present generation of plants; to develop evolutionary improved designs to be ready when needed; and to explore innovative longer-term concepts for deployment after the year 2000. The respective roles of government and the private sector are discussed

  11. Can we treat enough water to meet water quality goals

    Science.gov (United States)

    Denitrifying woodchip bioreactors are sized to treat a portion of subsurface drainage flow from a given system. Over sizing them can create conditions under which unintended consequences could occur. A potential solution for treating additional water is to use a cascading series of bioreactor cell...

  12. High performance light water reactor

    International Nuclear Information System (INIS)

    Squarer, D.; Schulenberg, T.; Struwe, D.; Oka, Y.; Bittermann, D.; Aksan, N.; Maraczy, C.; Kyrki-Rajamaeki, R.; Souyri, A.; Dumaz, P.

    2003-01-01

    The objective of the high performance light water reactor (HPLWR) project is to assess the merit and economic feasibility of a high efficiency LWR operating at thermodynamically supercritical regime. An efficiency of approximately 44% is expected. To accomplish this objective, a highly qualified team of European research institutes and industrial partners together with the University of Tokyo is assessing the major issues pertaining to a new reactor concept, under the co-sponsorship of the European Commission. The assessment has emphasized the recent advancement achieved in this area by Japan. Additionally, it accounts for advanced European reactor design requirements, recent improvements, practical design aspects, availability of plant components and the availability of high temperature materials. The final objective of this project is to reach a conclusion on the potential of the HPLWR to help sustain the nuclear option, by supplying competitively priced electricity, as well as to continue the nuclear competence in LWR technology. The following is a brief summary of the main project achievements:-A state-of-the-art review of supercritical water-cooled reactors has been performed for the HPLWR project.-Extensive studies have been performed in the last 10 years by the University of Tokyo. Therefore, a 'reference design', developed by the University of Tokyo, was selected in order to assess the available technological tools (i.e. computer codes, analyses, advanced materials, water chemistry, etc.). Design data and results of the analysis were supplied by the University of Tokyo. A benchmark problem, based on the 'reference design' was defined for neutronics calculations and several partners of the HPLWR project carried out independent analyses. The results of these analyses, which in addition help to 'calibrate' the codes, have guided the assessment of the core and the design of an improved HPLWR fuel assembly. Preliminary selection was made for the HPLWR scale

  13. Treat mine water using passive methods

    International Nuclear Information System (INIS)

    Kleinmann, R.L.P.; Hedin, R.S.

    1993-01-01

    Passive treatment represents an alternative to conventional chemical treatment of coal mine drainage. When successful, passive systems require less investment, less maintenance and usually are less expensive than conventional chemical treatment systems. As a result, during the last seven years, more than 500 passive systems have been constructed in the United States to treat coal mine drainage. Some exist as an alternative to conventional treatment; others serve as an inexpensive pretreatment step than can decrease subsequent chemical requirements. Sulfide minerals present in rock disturbed during mining can oxidize to form an acidic metal-laden solution, commonly known as acid mine drainage (AMD). Alkalinity present in the rock may partially or completely neutralize AMD, but if either acidity or excessive metal contaminants remain, the water must be treated before it can be discharged legally. The principal regulated contaminant metals of coal mine drainage are iron and manganese. Metal mine drainage often contains more toxic metals, such as cadmium, nickel, copper and zinc. Chemical treatment of AMD is estimated to cost America's mining industry more than $1 million a day. Three principal passive technologies are used in the treatment of coal mine drainage: Aerobic wetlands, wetlands constructed with an organic substrate and anoxic limestone drains (ALDS). The selection of the technology or combination of technologies to be used depends on the quality of the water being treated

  14. The Effects of Different Light Qualities on Gamma Ray-Treated Scenedesmus

    Directory of Open Access Journals (Sweden)

    Adoracion Arañez

    1992-06-01

    Full Text Available Unialgal culture of Scenedesmus quadricauda (Turp. Breb. suspended in distilled water was treated with 0 Gy (control, 40 Gy, 80 Gy, and 120 Gy gamma rays from a to 60Co source at Philippine Nuclear Research Institute, placed in one-liter flasks, enough Bold basal medium added to give a transmittance of 97% determined by using a spectrophotometer, kept in the dark for 24 hrs., then placed in vials and distributed equally in three growth chambers with white light, red light, and blue light. The lighting was continuous with algae subjected to the same light intensity, and the temperature maintained at 30±1° C. A sterile regimen was followed.For the first two weeks, the growth rates of algae under white light were highest, followed by those under red light, while those grown under blue light had the lowest growth rate. After the second week, differences in growth rates were not significant anymore. During the first week, generally low doses of gamma radiation had stimulating effects on growth rates while high doses had inhibitory effects on growth. The abnormal Scenedesmus observed were enlarged cells of normal shape in coenobia of two cells and four cells, enlarged cells that were not forming coenobia, coenobia composed of enlarged cells of abnormal shape, coenobia composed of enlarged cells of different sizes, cells with kidney-shape chloroplast, coenobia with cells that were not in alignment as in the normal ones, and cells that were colorless. Percentage of coenobia with enlarged cells determined one week after the treatment showed that higher doses generally produced more enlarged cells than lower doses. Treated algae grown in red light and blue light which showed lesser growth rates than those under white light had higher percentage of enlarged cells. Enlarged cells of normal shape were successfully propagated for more than ten generations.

  15. Supercritical-pressure light water cooled reactors

    CERN Document Server

    Oka, Yoshiaki

    2014-01-01

    This book focuses on the latest reactor concepts, single pass core and experimental findings in thermal hydraulics, materials, corrosion, and water chemistry. It highlights research on supercritical-pressure light water cooled reactors (SCWRs), one of the Generation IV reactors that are studied around the world. This book includes cladding material development and experimental findings on heat transfer, corrosion and water chemistry. The work presented here will help readers to understand the fundamental elements of reactor design and analysis methods, thermal hydraulics, materials and water

  16. Advances in light water reactor technologies

    CERN Document Server

    Saito, Takehiko; Ishiwatari, Yuki; Oka, Yoshiaki

    2010-01-01

    ""Advances in Light Water Reactor Technologies"" focuses on the design and analysis of advanced nuclear power reactors. This volume provides readers with thorough descriptions of the general characteristics of various advanced light water reactors currently being developed worldwide. Safety, design, development and maintenance of these reactors is the main focus, with key technologies like full MOX core design, next-generation digital I&C systems and seismic design and evaluation described at length. This book is ideal for researchers and engineers working in nuclear power that are interested

  17. Equations of state for light water

    International Nuclear Information System (INIS)

    Rubin, G.A.; Granziera, M.R.

    1983-01-01

    The equations of state for light water were developed, based on the tables of Keenan and Keyes. Equations are presented, describing the specific volume, internal energy, enthalpy and entropy of saturated steam, superheated vapor and subcooled liquid as a function of pressure and temperature. For each property, several equations are shown, with different precisions and different degress of complexity. (Author) [pt

  18. Facilitation of decommissioning light water reactors

    International Nuclear Information System (INIS)

    Moore, E.B. Jr.

    1979-12-01

    Information on design features, special equipment, and construction methods useful in the facilitation of decommissioning light water reactors is presented. A wide range of facilitation methods - from improved documentation to special decommissioning tools and techniques - is discussed. In addition, estimates of capital costs, cost savings, and radiation dose reduction associated with these facilitation methods are given

  19. Light-water reactor accident classification

    International Nuclear Information System (INIS)

    Washburn, B.W.

    1980-02-01

    The evolution of existing classifications and definitions of light-water reactor accidents is considered. Licensing practice and licensing trends are examined with respect to terms of art such as Class 8 and Class 9 accidents. Interim definitions, consistent with current licensing practice and the regulations, are proposed for these terms of art

  20. Developmental Light-Water Reactor Program

    International Nuclear Information System (INIS)

    Forsberg, C.W.

    1989-12-01

    This report summarizes the progress of the Developmental Light-Water Reactor (DLWR) Program at Oak Ridge National Laboratory in FY 1989. It also includes (1) a brief description of the program, (2) definition of goals, (3) earlier achievements, and (4) proposed future activities

  1. Steam explosions in light water reactors

    International Nuclear Information System (INIS)

    1981-01-01

    The report deals with a postulated accident caused by molten fuel falling into the lower plenum of the containment of a reactor. The analysis which is presented in the report shows that the thermal energy released in the resulting steam explosion is not enough to destroy the pressure vessel or the containment. The report was prepared for the Swedish Governmental Committee on steam explosion in light water reactors. It includes statements issued by internationally well-known specialists. (G.B.)

  2. effects of magnetically treated water on germination and growth

    African Journals Online (AJOL)

    Toshiba

    Keywords: irrigation, magnetically treated water, magnetic water, tomato. INTRODUCTION. Magnetic treatment of water is a modern technology in Agriculture and a non – chemical method of water treatment to soften the water, boost crop yield, improve crop quality and enhance effective utilization of the arable land.

  3. Ionic behavior of treated water at a water purification plant

    OpenAIRE

    Yanagida, Kazumi; Kawahigashi, Tatsuo

    2012-01-01

    [Abstract] Water at each processing stage in a water purification plant was extracted and analyzed to investigate changes of water quality. Investigations of water at each processing stage at the water purification plant are discussed herein.

  4. Penn State advanced light water reactor concept

    International Nuclear Information System (INIS)

    Borkowski, J.A.; Smith, K.A.; Edwards, R.M.; Robinson, G.E.; Schultz, M.A.; Klevans, E.H.

    1987-01-01

    The accident at Three Mile Island heightened concerns over the safety of nuclear power. In response to these concerns, a research group at the Pennsylvania State University (Penn State) undertook the conceptual design of an advanced light water reactor (ALWR) under sponsorship of the US Dept. of Energy (DOE). The design builds on the literally hundreds of years worth of experience with light water reactor technology. The concept is a reconfigured pressurized water reactor (PWR) with the capability of being shut down to a safe condition simply by removing all ac power, both off-site and on-site. Using additional passively activated heat sinks and replacing the pressurizer with a pressurizing pump system, the concept essentially eliminates the concerns of core damage associated with a total station blackout. Evaluation of the Penn State ALWR concept has been conducted using the EPRI Modular Modeling System (MMS). Results show that a superior response to normal operating transients can be achieved in comparison to the response with a conventional PWR pressurizer. The DOE-sponsored Penn State ALWR concept has evolved into a significant reconfiguration of a PWR leading to enhanced safety characteristics. The reconfiguration has touched a number of areas in overall plant design including a shutdown turbine in the secondary system, additional passively activated heat sinks, a unique primary side pressurizing concept, a low pressure cleanup system, reactor building layout, and a low power density core design

  5. Carbonation of Water Repellent-Treated Concrete

    Directory of Open Access Journals (Sweden)

    Peng Zhang

    2017-01-01

    Full Text Available Water repellent treatment has been considered an effective preventive method against water and aggressive ions penetration into concrete and consequently can improve the durability of concrete structures. In reality, many concrete structures are exposed to conditions with high risk of carbonation. In this contribution, one type of ordinary concrete had been prepared and surface impregnated by 400 g/m2 silane cream and 100 g/m2 and 400 g/m2 silane gel. In addition, integral water repellent concrete was produced by adding 2% silane emulsion. Then, the specimens were exposed to accelerated carbonation for 7, 28, and 72 days. The effect of water repellent treatment on carbonation of concrete has been investigated. The results indicate that surface impregnation reduced carbonation depth of concrete under RH 70%, but integral water repellent concrete increased carbonation. Carbonation reaction started behind the hydrophobic layer in the surface-impregnated concrete. The coefficient of carbonation can be described better by a hyperbolic function of time. Treatment by 400 g/m2 silane gel and silane cream showed better efficiency on reducing carbonation than usage of 100 g/m2. Coefficient of water capillary suction was decreased significantly by both surface impregnation and integral water repellent treatment. It is an effective method to protect concrete from water penetration into the material.

  6. Is light water reactor technology sustainable?

    International Nuclear Information System (INIS)

    Rothwell, G.; Van der Zwaan, B.

    2001-01-01

    This paper proposes criteria for determining ''intermediate sustainability'' over a 500-year horizon. We apply these criteria to Light Water Reactor (LWR) technology and the LWR industry. We conclude that LWR technology does not violate intermediate sustainability criteria for (1) environmental externalities, (2) worker and public health and safety, or (3) accidental radioactive release. However, it does not meet criteria to (1) efficiently use depleted uranium and (2) avoid uranium enrichment technologies that can lead to nuclear weapons proliferation. Finally, current and future global demand for LWR technology might be below the minimum needed to sustain the current global LWR industry. (author)

  7. Light-reactivation of (Tris-washed)-DPIP-treated chloroplasts

    International Nuclear Information System (INIS)

    Yamashita, Takashi; Tomita, Giiti

    1976-01-01

    Incorporation of 54 Mn into Tris (pH8.8, 1hr)-washed chloroplasts and oxygen evolving activity were stimulated by DPIP treatment and light-reactivation, but inhibited by atebrin, DCCD, gramicidin J, DCMU and EDTA. Omission of DTT on the light-reactivation resulted in accumulation or deposit of Mn in chloroplasts which had no function for the recovery of oxygen-evolving activity. The chlorophyll fluorescence quenched by Tris-washing was restored by DPIP-treatment and light-reactivation. The chloroplast structure, monitored by its packed volume and optical density at 750mm, changed reversibly with inhibition and DPIP-treatment. The action spectrum of light-reactivation suggested that the effective light-receptor might be photosystem II. (auth.)

  8. Materials for high performance light water reactors

    Science.gov (United States)

    Ehrlich, K.; Konys, J.; Heikinheimo, L.

    2004-05-01

    A state-of-the-art study was performed to investigate the operational conditions for in-core and out-of-core materials in a high performance light water reactor (HPLWR) and to evaluate the potential of existing structural materials for application in fuel elements, core structures and out-of-core components. In the conventional parts of a HPLWR-plant the approved materials of supercritical fossil power plants (SCFPP) can be used for given temperatures (⩽600 °C) and pressures (≈250 bar). These are either commercial ferritic/martensitic or austenitic stainless steels. Taking the conditions of existing light water reactors (LWR) into account an assessment of potential cladding materials was made, based on existing creep-rupture data, an extensive analysis of the corrosion in conventional steam power plants and available information on material behaviour under irradiation. As a major result it is shown that for an assumed maximum temperature of 650 °C not only Ni-alloys, but also austenitic stainless steels can be used as cladding materials.

  9. Environmentally assisted cracking in Light Water Reactors

    International Nuclear Information System (INIS)

    Chung, H.M.; Chopra, O.K.; Ruther, W.E.; Kassner, T.F.; Michaud, W.F.; Park, J.Y.; Sanecki, J.E.; Shack, W.J.

    1993-09-01

    This report summarizes work performed by Argonne National Laboratory on fatigue and environmentally assisted cracking (EAC) in light water reactors (LWRs) during the six months from October 1992 to March 1993. Fatigue and EAC of piping, pressure vessels, and core components in LWRs are important concerns as extended reactor lifetimes are envisaged. Topics that have been investigated include (1) fatigue of low-alloy steel used in piping, steam generators, and reactor pressure vessels. (2) EAC of cast stainless steels (SSs), (3) radiation-induced segregation and irradiation-assisted stress corrosion cracking of Type 304 SS after accumulation of relatively high fluence, and (4) EAC of low-alloy steels. Fatigue tests were conducted on medium-sulfur-content A106-Gr B piping and A533-Gr B pressure vessel steels in simulated PWR water and in air. Additional crack growth data were obtained on fracture-mechanics specimens of cast austenitic SSs in the as-received and thermally aged conditions and chromium-nickel-plated A533-Gr B steel in simulated boiling-water reactor (BWR) water at 289 degrees C. The data were compared with predictions based on crack growth correlations for ferritic steels in oxygenated water and correlations for wrought austenitic SS in oxygenated water developed at ANL and rates in air from Section XI of the ASME Code. Microchemical and microstructural changes in high- and commercial-purity Type 304 SS specimens from control-blade absorber tubes and a control-blade sheath from operating BWRs were studied by Auger electron spectroscopy and scanning electron microscopy

  10. Pre-treating water with non-thermal plasma

    Science.gov (United States)

    Cho, Young I.; Fridman, Alexander; Rabinovich, Alexander; Cho, Daniel J.

    2017-07-04

    The present invention consists of a method of pre-treatment of adulterated water for distillation, including adulterated water produced during hydraulic fracturing ("fracking") of shale rock during natural gas drilling. In particular, the invention is directed to a method of treating adulterated water, said adulterated water having an initial level of bicarbonate ion in a range of about 250 ppm to about 5000 ppm and an initial level of calcium ion in a range of about 500 ppm to about 50,000 ppm, said method comprising contacting the adulterated water with a non-thermal arc discharge plasma to produce plasma treated water having a level of bicarbonate ion of less than about 100 ppm. Optionally, the plasma treated water may be further distilled.

  11. Attosecond light sources in the water window

    Science.gov (United States)

    Ren, Xiaoming; Li, Jie; Yin, Yanchun; Zhao, Kun; Chew, Andrew; Wang, Yang; Hu, Shuyuan; Cheng, Yan; Cunningham, Eric; Wu, Yi; Chini, Michael; Chang, Zenghu

    2018-02-01

    As a compact and burgeoning alternative to synchrotron radiation and free-electron lasers, high harmonic generation (HHG) has proven its superiority in static and time-resolved extreme ultraviolet spectroscopy for the past two decades and has recently gained many interests and successes in generating soft x-ray emissions covering the biologically important water window spectral region. Unlike synchrotron and free-electron sources, which suffer from relatively long pulse width or large time jitter, soft x-ray sources from HHG could offer attosecond time resolution and be synchronized with their driving field to investigate time-resolved near edge absorption spectroscopy, which could reveal rich structural and dynamical information of the interrogated samples. In this paper, we review recent progresses on generating and characterizing attosecond light sources in the water window region. We show our development of an energetic, two-cycle, carrier-envelope phase stable laser source at 1.7 μm and our achievement in producing a 53 as soft x-ray pulse covering the carbon K-edge in the water window. Such source paves the ways for the next generation x-ray spectroscopy with unprecedented temporal resolution.

  12. Radiation Protection at Light Water Reactors

    CERN Document Server

    Prince, Robert

    2012-01-01

    This book is aimed at Health Physicists wishing to gain a better understanding of the principles and practices associated with a light water reactor (LWR) radiation protection program. The role of key program elements is presented in sufficient detail to assist practicing radiation protection professionals in improving and strengthening their current program. Details related to daily operation and discipline areas vital to maintaining an effective LWR radiation protection program are presented. Programmatic areas and functions important in preventing, responding to, and minimizing radiological incidents and the importance of performing effective incident evaluations and investigations are described. Elements that are integral in ensuring continuous program improvements are emphasized throughout the text.

  13. Light water reactor lower head failure analysis

    Energy Technology Data Exchange (ETDEWEB)

    Rempe, J.L.; Chavez, S.A.; Thinnes, G.L. [EG and G Idaho, Inc., Idaho Falls, ID (United States)] [and others

    1993-10-01

    This document presents the results from a US Nuclear Regulatory Commission-sponsored research program to investigate the mode and timing of vessel lower head failure. Major objectives of the analysis were to identify plausible failure mechanisms and to develop a method for determining which failure mode would occur first in different light water reactor designs and accident conditions. Failure mechanisms, such as tube ejection, tube rupture, global vessel failure, and localized vessel creep rupture, were studied. Newly developed models and existing models were applied to predict which failure mechanism would occur first in various severe accident scenarios. So that a broader range of conditions could be considered simultaneously, calculations relied heavily on models with closed-form or simplified numerical solution techniques. Finite element techniques-were employed for analytical model verification and examining more detailed phenomena. High-temperature creep and tensile data were obtained for predicting vessel and penetration structural response.

  14. Light water reactor lower head failure analysis

    International Nuclear Information System (INIS)

    Rempe, J.L.; Chavez, S.A.; Thinnes, G.L.

    1993-10-01

    This document presents the results from a US Nuclear Regulatory Commission-sponsored research program to investigate the mode and timing of vessel lower head failure. Major objectives of the analysis were to identify plausible failure mechanisms and to develop a method for determining which failure mode would occur first in different light water reactor designs and accident conditions. Failure mechanisms, such as tube ejection, tube rupture, global vessel failure, and localized vessel creep rupture, were studied. Newly developed models and existing models were applied to predict which failure mechanism would occur first in various severe accident scenarios. So that a broader range of conditions could be considered simultaneously, calculations relied heavily on models with closed-form or simplified numerical solution techniques. Finite element techniques-were employed for analytical model verification and examining more detailed phenomena. High-temperature creep and tensile data were obtained for predicting vessel and penetration structural response

  15. Lasers or light sources for treating port-wine stains

    DEFF Research Database (Denmark)

    Faurschou, Annesofie; Olesen, Anne Braae; Leonardi-Bee, Jo

    2011-01-01

    Port-wine stains are birthmarks caused by malformations of blood vessels in the skin. Port-wine stains manifest themselves in infancy as a flat, red mark and do not regress spontaneously but may, if untreated, become darker and thicker in adult life. The profusion of various lasers and light...

  16. Environmentally assisted cracking in light water reactors

    Energy Technology Data Exchange (ETDEWEB)

    Chopra, O.K.; Chung, H.M.; Gruber, E.E. [and others

    1996-07-01

    This report summarizes work performed by Argonne National Laboratory on fatigue and environmentally assisted cracking (EAC) in light water reactors (LWRs) from April 1995 to December 1995. Topics that have been investigated include fatigue of carbon and low-alloy steel used in reactor piping and pressure vessels, EAC of Alloy 600 and 690, and irradiation-assisted stress corrosion cracking (IASCC) of Type 304 SS. Fatigue tests were conducted on ferritic steels in water that contained various concentrations of dissolved oxygen (DO) to determine whether a slow strain rate applied during different portions of a tensile-loading cycle are equally effective in decreasing fatigue life. Crack-growth-rate tests were conducted on compact-tension specimens from several heats of Alloys 600 and 690 in simulated LWR environments. Effects of fluoride-ion contamination on susceptibility to intergranular cracking of high- and commercial- purity Type 304 SS specimens from control-tensile tests at 288 degrees Centigrade. Microchemical changes in the specimens were studied by Auger electron spectroscopy and scanning electron microscopy to determine whether trace impurity elements may contribute to IASCC of these materials.

  17. Visible light photocatalytic properties of novel molybdenum treated ...

    Indian Academy of Sciences (India)

    si, Chungnam-do 356-706, Korea. MS received 17 August 2010; revised 21 October 2010. Abstract. Two types of molybdenum–carbon nanotubes and molybdenum treated carbon nanotubes/titania com- posites were prepared using a sol–gel ...

  18. Visible Light Activated Photocatalytic Water Polishing System, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — This proposal targets development of a LED light activated photocatalytic water polishing system that enables reduction of organic impurities (TOC and...

  19. Environmentally assisted cracking in light water reactors

    International Nuclear Information System (INIS)

    Shack, W.J.

    1983-01-01

    The objectives of this program are to develop an independent capability for the detection and control of stress-corrosion cracking (SCC) in light-water reactor (LWR) systems and to evaluate of the technical merits of proposed remedies for the problem. The experimental work is initially concentrated on problems related to intergranular SCC in BWR piping systems. The BWR utilities, the reactor vendors, and related research organizations have developed remedies for the pipe cracking problems and have begun to develop the crack-growth-rate data base which is needed to assure the integrity of degraded piping and to develop an adequate plan for the inspection and monitoring of such piping. The performance of the remedies in laboratory tests is quite encouraging, but there are still technical questions which must be addressed to ensure that the laboratory results will accurately reflect performance in-reactor. For existing plants even with the assurance of leak-before-break it is important to upgrade the capability to detect leaks rather than completely relying on periodic in-service inspection. Although other leak detection system (e.g., moisture-sensitive tapes) will be considered, acoustic leak detection systems seem to offer the best combination of sensitivity, ability to locate a leak, and leak-rate measurement. The assessment and development of a practical leak detection system is another important objective of this program

  20. Nuclear fuel for light water reactors

    International Nuclear Information System (INIS)

    Etemad, A.

    1976-01-01

    The goal of the present speech is to point out some of the now-a-day existing problems related to the fuel cycle of light water reactors and to foresee their present and future solutions. Economical aspects of nuclear power generation have been considerably improving, partly through technological advancements and partly due to the enlargement of unit capacity. The fuel cycle, defined in the course of this talk, discusses the exploration, mining, ore concentration, purification, conversion, enrichment, manufacturing of fuel elements, their utilization in a reactor, their discharge and subsequent storage, reprocessing, and their re-use or disposal. Uranium market in the world and the general policy of several uranium owning countries are described. The western world requirement for uranium until the year 2000, uranium resources and the nuclear power programs in the United States, Australia, Canada, South Africa, France, India, Spain, and Argentina are discussed. The participation of Iran in a large uranium enrichment plant based on French diffusion technology is mentioned

  1. Photoelectrochemical water splitting: optimizing interfaces and light absorption

    NARCIS (Netherlands)

    Park, Sun-Young

    2015-01-01

    In this thesis several photoelectrochemical water splitting devices based on semiconductor materials were investigated. The aim was the design, characterization, and fabrication of solar-to-fuel devices which can absorb solar light and split water to produce hydrogen.

  2. Diverse biological effects of electromagnetic-treated water.

    Science.gov (United States)

    Yamabhai, Montarop; Chumseng, Suchintana; Yoohat, Kirana; Srila, Witsanu

    2014-07-01

    The effects of water treated with an electromagnetic field (EMF) were investigated on two biological systems, humans and plants. Purified de-ionised water was treated by (1) boiling, (2) exposure to microwave radiation, and (3) low frequency electromagnetic oscillation molecular resonance effect technology (MRET), before being used to prepare media for culturing human peripheral blood mononuclear cells (PBMC) from three healthy females. Our results indicated that PBMC culture in MRET-activated medium showed significantly less oxidative metabolism when compared to media prepared from other types of water. As for the effects on soybean, our results indicated that both MRET- and microwave-treated water greatly enhanced the length of the root. These results suggested that electromagnetic-treated water can have diverse biological effects on both animal and plant cells. Since these effects are related to the 'Memory of Water', hypothesis which has been suggested as an explanation of the action of high homeopathic dilutions, our finding warrant a further investigation on the mechanisms of various types of physically conditioned water on specific cellular activities. Copyright © 2013 The Faculty of Homeopathy. Published by Elsevier Ltd. All rights reserved.

  3. Light scattering by particles in water theoretical and experimental foundations

    CERN Document Server

    Jonasz, Miroslaw

    2007-01-01

    Light scattering-based methods are used to characterize small particles suspended in water in a wide range of disciplines ranging from oceanography, through medicine, to industry. The scope and accuracy of these methods steadily increases with the progress in light scattering research. This book focuses on the theoretical and experimental foundations of the study and modeling of light scattering by particles in water and critically evaluates the key constraints of light scattering models. It begins with a brief review of the relevant theoretical fundamentals of the interaction of light with condensed matter, followed by an extended discussion of the basic optical properties of pure water and seawater and the physical principles that explain them. The book continues with a discussion of key optical features of the pure water/seawater and the most common components of natural waters. In order to clarify and put in focus some of the basic physical principles and most important features of the experimental data o...

  4. Engineering Characteristics of Chemically Treated Water-Repellent Kaolin

    Directory of Open Access Journals (Sweden)

    Youngmin Choi

    2016-12-01

    Full Text Available Water-repellent soils have a potential as alternative construction materials that will improve conventional geotechnical structures. In this study, the potential of chemically treated water-repellent kaolin clay as a landfill cover material is explored by examining its characteristics including hydraulic and mechanical properties. In order to provide water repellency to the kaolin clay, the surface of clay particle is modified with organosilanes in concentrations (CO ranging from 0.5% to 10% by weight. As the CO increases, the specific gravity of treated clay tends to decrease, whereas the total organic carbon content of the treated clay tends to increase. The soil-water contact angle increases with an increase in CO until CO = 2.5%, and then maintains an almost constant value (≈134.0°. Resistance to water infiltration is improved by organosilane treatment under low hydrostatic pressure. However, water infiltration resistance under high hydrostatic pressure is reduced or exacerbated to the level of untreated clay. The maximum compacted dry weight density decreases with increasing CO. As the CO increases, the small strain shear modulus increases, whereas the effect of organosilane treatment on the constrained modulus is minimal. The results indicate that water-repellent kaolin clay possesses excellent engineering characteristics for a landfill cover material.

  5. A strategy for improving pump and treat ground water remediation

    International Nuclear Information System (INIS)

    Hoffman, F.

    1992-07-01

    Established pump and treat ground water remediation has a reputation for being too expensive and time consuming, especially when cleanup standards are set at very low levels, e.g., 50 ft below ground surface) widespread ground water contamination. The perceived shortcomings of pump and treat result from the (1) tendency of most contaminants to sorb to formation materials, thus retarding contaminant removal; (2) geologic complexity, which requires detailed characterization for the design of optimal extraction systems within available resources; and (3) failure to apply dynamic well field management techniques. An alternative strategy for improving pump and treat ground water remediation consists of (1) detailed characterization of the geology, hydrology, and chemistry; (2) use of computer-aided data interpretation, data display, and decision support systems; (3) removal of sources, if possible; (4) initial design for plume containment and source remediation; (5) phased installation of the well field; (6) detailed monitoring of the remediation; (7) active ongoing re-evaluation of the operating well field, including redesign as appropriate (dynamic management); (8) re-injection of treated ground water to speed the flushing of contaminants; and (9) setting of appropriate cleanup levels or goals. Use of some or all of these techniques can dramatically reduce the time required to achieve cleanup goals and thus the cost of ground water remediation

  6. Light Water Reactor Sustainability Accomplishments Report

    Energy Technology Data Exchange (ETDEWEB)

    McCarthy, Kathryn A. [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2015-02-01

    Welcome to the 2014 Light Water Reactor Sustainability (LWRS) Program Accomplishments Report, covering research and development highlights from 2014. The LWRS Program is a U.S. Department of Energy research and development program to inform and support the long-term operation of our nation’s commercial nuclear power plants. The research uses the unique facilities and capabilities at the Department of Energy national laboratories in collaboration with industry, academia, and international partners. Extending the operating lifetimes of current plants is essential to supporting our nation’s base load energy infrastructure, as well as reaching the Administration’s goal of reducing greenhouse gas emissions to 80% below 1990 levels by the year 2050. The purpose of the LWRS Program is to provide technical results for plant owners to make informed decisions on long-term operation and subsequent license renewal, reducing the uncertainty, and therefore the risk, associated with those decisions. In January 2013, 104 nuclear power plants operated in 31 states. However, since then, five plants have been shut down (several due to economic reasons), with additional shutdowns under consideration. The LWRS Program aims to minimize the number of plants that are shut down, with R&D that supports long-term operation both directly (via data that is needed for subsequent license renewal), as well indirectly (with models and technology that provide economic benefits). The LWRS Program continues to work closely with the Electric Power Research Institute (EPRI) to ensure that the body of information needed to support SLR decisions and actions is available in a timely manner. This report covers selected highlights from the three research pathways in the LWRS Program: Materials Aging and Degradation, Risk-Informed Safety Margin Characterization, and Advanced Instrumentation, Information, and Control Systems Technologies, as well as a look-ahead at planned activities for 2015. If you

  7. Transmission of Curing Light through Moist, Air-Dried, and EDTA Treated Dentine and Enamel.

    Science.gov (United States)

    Uusitalo, E; Varrela, J; Lassila, L; Vallittu, P K

    2016-01-01

    Objective. This study measured light transmission through enamel and dentin and the effect of exposed dentinal tubules to light propagation. Methods. Light attenuation through enamel and dentin layers of various thicknesses (1 mm, 2 mm, 3 mm, and 4 mm) was measured using specimens that were (1) moist and (2) air-dried (n = 5). Measurements were repeated after the specimens were treated with EDTA. Specimens were transilluminated with a light curing unit (maximum power output 1869 mW/cm(2)), and the mean irradiance power of transmitting light was measured. The transmission of light through teeth was studied using 10 extracted intact human incisors and premolars. Results. Transmitted light irradiance through 1 mm thick moist discs was 500 mW/cm(2) for enamel and 398 mW/cm(2) for dentin (p Beer-Lambert's law.

  8. Identification of Entamoeba moshkovskii in Treated Waste Water Used for Agriculture.

    Science.gov (United States)

    Fonseca, Jairo Andres; Heredia, Rubén Darío; Ortiz, Carolina; Mazo, Martín; Clavijo-Ramírez, Carlos Arturo; Lopez, Myriam Consuelo

    2016-03-01

    We conducted an observational study to determine the prevalence of Entamoeba spp., in samples collected in a waste water treatment plant that provides water for agricultural irrigation. Samples were collected weekly over a period of 10 weeks at representative contamination stages from within the treatment plant. Protozoan identification was performed via light microscopy and culture. PCR amplification of small subunit rRNA gene sequences of E. histolytica/dispar/moshkovskii was performed in culture positive samples. Light microscopy revealed the presence of Entamoeba spp., in 70% (14/20) of the raw waste water samples and in 80% (8/10) of the treated water samples. PCR amplification after culture at both 24 and 37°C revealed that 100% (29/29) of the raw waste water samples and 78.6% (11/14) of the treated waste water were positive for E. moshkovskii. We report the first isolation of E. moshkovskii in Colombia, confirmed by PCR. Recent reports of E. moshkovskii pathogenic potential suggest this finding could constitute a public health risk for people exposed to this water.

  9. Near real-time analysis of tritium in treated water

    Energy Technology Data Exchange (ETDEWEB)

    Skibo, A. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2017-09-27

    The Tokyo Electric Power Company (TEPCO) is managing large quantities of treated water at the Fukushima Daiichi Nuclear Power Station. Moving forward, TEPCO will be discharging from the site clean water that meets agreed criteria. As part of agreements with stakeholders, TEPCO is planning to carefully monitor the water prior to discharge to assure compliance. The objective of this proposal is to support implementation of an on-line “real-time” (continuous or semi-continuous) tritium monitor that will reliably measure levels down to the agreed target 1500 Becquerels per liter (Bq/L).

  10. Mechanical properties of wood from Pinus sylvestris L. treated with Light Organic Solvent Preservative and with waterborne Copper Azole

    Energy Technology Data Exchange (ETDEWEB)

    Villasante, A.; Laina, R.; Rojas, J. A. M.; Rojas, I. M.; Vignote, S.

    2013-07-01

    Aim of study: To determine the effect on wood from Pinus sylvestris of treatment with preservatives on mechanical properties and to establish the relation between the penetration and compression strenght. Area of study: Spain. Material and methods: 40 samples of defect-free wood from Pinus sylvestris L. were treated with Light Organic Solvent Preservative (Vacsol Azure WR 2601) and 50 with waterborne Copper Azole (Tanalith E 3492). 40 control samples were not treated (water or preservative). Mechanical resistance to static bending, modulus of elasticity and compression strength parallel to the grain were compared with untreated wood. Regression analysis between the penetration and compression strength parallel was done with the samples treated with waterborne preservative. Main results: The results indicate that the treated wood (with either product) presents a statistically significant increase in mechanical resistance in all three mechanical characteristics. The results obtained differ from earlier studies carried out by other authors. There was no correlation between parallel compression strength and the degree of impregnation of the wood with waterborne Copper Azole. The most probable explanation for these results concerns changes in pressure during treatment. The use of untreated control samples instead of samples treated only with water is more likely to produce significant results in the mechanical resistance studies. Research highlights: Treated wood presents a statistically significant increase in MOE, modulus of rupture to static bending and parallel compression strength. There was no correlation between parallel compression strength and the degree of impregnation with waterborne preservative. (Author)

  11. Can light water reactors be proliferation resistant?

    International Nuclear Information System (INIS)

    Abushady, Yousry

    2001-01-01

    During the last decade several questions were raised concerning the proliferation issues of Light Water Reactors (LWRs) in comparison with other types of power reactors, particularly Gas Cooled Reactors (GCRs) and Heavy Water Reactors (HWRs). These questions were strongly highlighted when the Agreed Framework between the United States and the DPRK was signed in October 1994 and following the formation of KEDO organization to provide two LWRs to DPRK in replacement of all its GCRs in its nuclear program. One might summarize the main questions into three groups, mainly: 1. Can LWRs produce weapon-grade Plutonium (Pu)? 2. Why is the LWR type considered as a better option with regard to non-proliferation compared to other power reactors - particularly GCR and HWR types? 3. How could LWRs be more resistant to proliferation? This paper summarizes the effort to answer these questions. Included tables present numerical parameters for Pu production capability of the three main reactor types (LWRs, GCRs and HWRs) of a 400 MWe power reactor unit, during normal operation, and during abnormal operation to produce weapon grade Pu. Can LWRs produce weapon-grade Pu? It is seen from the available data that weapon-grade Pu could be produced in LWR fuel, as in the fuel of most other power reactor types, by limiting fuel irradiation to two or three months only. However, such production, though possible, is exceptional. In a recent study 5% of LWRs under IAEA safeguards have spent fuel inventory containing limited amount of high-grade Pu. The equilibrium burnup of discharged fuel is in the order of 33,000 MWD/T. However and due to lower enrichment of initial inventory almost half of that burnup is produced. In normal situations the discharged initial inventory has a Pu grade which is less than weapon grade and is unlikely to be used for weapon production. Why LWR the type is considered as a better option for non-proliferation Referring to tables, one can conclude that LWRs make less Pu

  12. Environmentally assisted cracking in light water reactors

    International Nuclear Information System (INIS)

    Kassner, T.F.; Ruther, W.E.; Chung, H.M.; Hicks, P.D.; Hins, A.G.; Park, J.Y.; Soppet, W.K.; Shack, W.J.

    1992-03-01

    This report summarizes work performed by Argonne National Laboratory on fatigue and environmentally assisted cracking in high water reactors during the six months from April 1991 through September 1991. Topics that have been investigated during this period include (1) fatigue and stress corrosion cracking (SCC) of low-alloy steel used in piping and in steam generator and reactor pressure vessels; (2) role of chromate and sulfate in simulated boiling water reactor (BWR) water on SCC of sensitized Type 304 SS; and (3) radiation-induced segregation (RIS) and irradiation-assisted SCC of Type 304 SS after accumulation of relatively high fluence. Fatigue data were obtained on medium-S-content A533-Gr B and A106-Gr B steels in high-purity (HP) deoxygenated water, in simulated pressurized water reactor (PWR) water, and in air. Crack-growth-rates (CGRs) of composite specimens of A533-Gr B/Inconel-182/Inconel-600 (plated with nickel) and homogeneous specimens of A533-Gr B were determined under small- amplitude cyclic loading in HP water with ∼ 300 ppb dissolved oxygen. CGR tests on sensitized Type 304 SS indicate that low chromate concentrations in BWR water (25--35 ppb) may actually have a beneficial effect on SCC if the sulfate concentration is below a critical level. Microchemical and microstructural changes in HP and commercial-purity Type 304 SS specimens from control-blade absorber tubes used in two operating BWRs were studied by Auger electron spectroscopy and scanning electron microscopy, and slow-strain,rate- tensile tests were conducts on tubular specimens in air and in simulated BWR water at 289 degrees C

  13. Microbial pathogens in source and treated waters from drinking water treatment plants in the US

    Science.gov (United States)

    An occurrence survey was conducted on selected pathogens in source and treated drinking water collected from 25 drinking water treatment plants (DWTPs) in the United States. Water samples were analyzed for the protozoa Giardia and Cryptosporidium (EPA Method 1623); the fungi Asp...

  14. Water quality changes in a post-herbicide treated water hyacinth ...

    African Journals Online (AJOL)

    Water quality changes after in situ chemical control of water hyacinth (Eichhornia crassipes (Mart.) Solm-Laub. using five chemical products were monitored in a green house experiment. The observed changes in water quality coincided with the loss of treated plant photosynthetic activities, submerging of the dead plants in ...

  15. Modeling Water Clarity and Light Quality in Oceans

    Directory of Open Access Journals (Sweden)

    Mohamed A. Abdelrhman

    2016-11-01

    Full Text Available Phytoplankton is a primary producer of organic compounds, and it forms the base of the food chain in ocean waters. The concentration of phytoplankton in the water column controls water clarity and the amount and quality of light that penetrates through it. The availability of adequate light intensity is a major factor in the health of algae and phytoplankton. There is a strong negative coupling between light intensity and phytoplankton concentration (e.g., through self-shading by the cells, which reduces available light and in return affects the growth rate of the cells. Proper modeling of this coupling is essential to understand primary productivity in the oceans. This paper provides the methodology to model light intensity in the water column, which can be included in relevant water quality models. The methodology implements relationships from bio-optical models, which use phytoplankton chlorophyll a (chl-a concentration as a surrogate for light attenuation, including absorption and scattering by other attenuators. The presented mathematical methodology estimates the reduction in light intensity due to absorption by pure seawater, chl-a pigment, non-algae particles (NAPs and colored dissolved organic matter (CDOM, as well as backscattering by pure seawater, phytoplankton particles and NAPs. The methods presented facilitate the prediction of the effects of various environmental and management scenarios (e.g., global warming, altered precipitation patterns, greenhouse gases on the wellbeing of phytoplankton communities in the oceans as temperature-driven chl-a changes take place.

  16. The safety of light water reactors

    International Nuclear Information System (INIS)

    Pershagen, B.

    1986-04-01

    The book describes the principles and practices of reactor safety as applied to the design, regulation and operation of both pressurized water reactors and boiling water reactors. The central part of the book is devoted to methods and results of safety analysis. Some significant events are described, notably the Three Mile Island accident. The book concludes with a chapter on the PIUS principle of inherent reactor safety as applied to the SECURE type of reactor developed in Sweden. (G.B.)

  17. 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.

  18. Process for treating waste water having low concentrations of metallic contaminants

    Science.gov (United States)

    Looney, Brian B; Millings, Margaret R; Nichols, Ralph L; Payne, William L

    2014-12-16

    A process for treating waste water having a low level of metallic contaminants by reducing the toxicity level of metallic contaminants to an acceptable level and subsequently discharging the treated waste water into the environment without removing the treated contaminants.

  19. Mechanical properties of wood from Pinus sylvestris L. treated with Light Organic Solvent Preservative and with waterborne Copper Azole

    Directory of Open Access Journals (Sweden)

    A.M. Villasante

    2013-12-01

    Full Text Available Aim of study: To determine the effect on wood from Pinus sylvestris of treatment with preservatives on mechanical properties and to establish the relation between the penetration and compression strength.Area of study: SpainMaterial and Methods: 40 samples of defect-free wood from Pinus sylvestris L. were treated with Light Organic Solvent Preservative (Vacsol Azure WR 2601 and 50 with waterborne Copper Azole (Tanalith E 3492. 40 control samples were not treated (water or preservative. Mechanical resistance to static bending, modulus of elasticity and compression strength parallel to the grain were compared with untreated wood. Regression analysis between the penetration and compression strength parallel was done with the samples treated with waterborne preservative.Main results: The results indicate that the treated wood (with either product presents a statistically significant increase in mechanical resistance in all three mechanical characteristics. The results obtained differ from earlier studies carried out by other authors.There was no correlation between parallel compression strength and the degree of impregnation of the wood with waterborne Copper Azole . The most probable explanation for these results concerns changes in pressure during treatment.The use of untreated control samples instead of samples treated only with water is more likely to produce significant results in the mechanical resistance studies.Research highlights: Treated wood presents a statistically significant increase in MOE, modulus of rupture to static bending  and parallel compression strength.There was no correlation between parallel compression strength and the degree of impregnation with waterborne preservative.Keywords: Light Organic Solvent Preservative; MOE; parallel compression; static bending; waterborne Copper Azole; wood technology.

  20. Transmission of Curing Light through Moist, Air-Dried, and EDTA Treated Dentine and Enamel

    Directory of Open Access Journals (Sweden)

    E. Uusitalo

    2016-01-01

    Full Text Available Objective. This study measured light transmission through enamel and dentin and the effect of exposed dentinal tubules to light propagation. Methods. Light attenuation through enamel and dentin layers of various thicknesses (1 mm, 2 mm, 3 mm, and 4 mm was measured using specimens that were (1 moist and (2 air-dried (n=5. Measurements were repeated after the specimens were treated with EDTA. Specimens were transilluminated with a light curing unit (maximum power output 1869 mW/cm2, and the mean irradiance power of transmitting light was measured. The transmission of light through teeth was studied using 10 extracted intact human incisors and premolars. Results. Transmitted light irradiance through 1 mm thick moist discs was 500 mW/cm2 for enamel and 398 mW/cm2 for dentin (p<0.05. The increase of the specimen thickness decreased light transmission in all groups (p<0.005, and moist specimens attenuated light less than air-dried specimens in all thicknesses (p<0.05. EDTA treatment increased light transmission from 398 mW/cm2 to 439 mW/cm2 (1 mm dentin specimen thickness (p<0.05. Light transmission through intact premolar was 6.2 mW/cm2 (average thickness 8.2 mm and through incisor was 37.6 mW/cm2 (average thickness 5.6 mm. Conclusion. Light transmission through enamel is greater than that through dentin, probably reflecting differences in refractive indices and extinction coefficients. Light transmission through enamel, dentin, and extracted teeth seemed to follow Beer-Lambert’s law.

  1. Passive systems for light water reactors

    International Nuclear Information System (INIS)

    Adinolfi, R.; Noviello, L.

    1990-01-01

    The paper reviews the most original concepts that have been considered in Italy for the back-fitting of the nuclear power plants in order to reduce the probability and the importance of the release to the environment in case of a core melt. With reference either to BWR or PWR, passive concepts have been considered for back-fitting in the following areas: pump seals damage prevention and ECCS passive operation; reactor passive depressurization; molten reactor core passive cooling; metal containment passive water cooling through a water tank located at high level; containment isolation improvement through a sealing system; containment leaks control and limitation of environmental release. In addition some considerations will be made on the protection against external events introduced from the beginning on the PUN design either on building and equipment lay-out either on structure design. (author). 5 figs

  2. Light induced degradation of testosterone in waters

    Energy Technology Data Exchange (ETDEWEB)

    Vulliet, Emmanuelle, E-mail: e.vulliet@sca.cnrs.fr [Service Central d' Analyse du CNRS - USR59, Chemin du Canal, F-69360 Solaize (France); Falletta, Marine; Marote, Pedro [Laboratoire des Sciences Analytiques - UMR 5180, Universite Claude Bernard, 43 bd du 11 Novembre 1918, F-69622 Villeurbanne Cedex (France); Lomberget, Thierry [Laboratoire de Chimie Therapeutique, Universite de Lyon, Universite Lyon 1, Faculte de Pharmacie-ISPB, EA 4443 Biomolecules, Cancer et Chimioresistances, INSERM U863 Hormones steroides et proteines de liaison, IFR 62, 8 avenue Rockefeller, F-69373, Lyon Cedex 08 (France); Paisse, Jean-Olivier; Grenier-Loustalot, Marie-Florence [Service Central d' Analyse du CNRS - USR59, Chemin du Canal, F-69360 Solaize (France)

    2010-08-01

    The degradation of testosterone under simulated irradiations was studied in phosphate buffers and in natural waters at various excitation wavelengths. The quantum yield of photolysis was significantly lower at 313 nm (2.4 x 10{sup -3}) than at 254 nm (0.225). The formation of several photoproducts was observed, some of them being rapidly transformed in turn while others show higher stability towards subsequent irradiations. The nature of the main products was tentatively identified, both deduced from their spectral and spectrometric data and by comparison with synthesised standard compounds. Among the obtained photoproducts, the main one is possibly a spiro-compound, hydroxylated derivative of testosterone originating from the photohydratation of the enone group. The photodegradation pathway includes also photorearrangements. One of them leads to (1,5,10)-cyclopropyl-17{beta}-hydroxyandrostane-2-one. The pH of the water does not seem to affect the rate of phototransformation and the nature of the by-products.

  3. Pustular Palmoplantar Psoriasis Successfully Treated with Nb-UVB Monochromatic Excimer Light: A Case-Report

    Directory of Open Access Journals (Sweden)

    Serena Gianfaldoni

    2017-07-01

    Full Text Available Barber’s palmoplantar pustulosis (PPP is a form of localised pustular psoriasis, affecting the palmar and plantar surfaces. It is a chronic disease, with a deep impact on the patients’ quality of life. The Authors discuss a case of Baber Psoriasis successfully treated with monochromatic excimer light.

  4. Plant Control of the High Performance Light Water Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Schlagenhaufer, Marc; Starflinger, J.; Schulenberg, T. [Institute for Nuclear and Energy Technologies, Forschungszentrum Karlsruhe GmbH, Hermann-von-Helmholtz-Platz 1, Eggenstein-Leopoldshafen, Baden-Wuertemberg 76344 (Germany)

    2009-06-15

    The latest design concept of the High Performance Light Water Reactor (HPLWR) includes a thermal core in which supercritical water at 25 MPa inlet pressure is heated up from 280 deg. C reactor inlet temperature to 500 deg. C core exit temperature in three steps with intermediate coolant mixing to minimize peak cladding temperatures of the fuel rods. A direct supercritical steam cycle of the HPLWR has been designed with high, intermediate and low pressure turbines with a single reheat to 441 deg. C at 4.04 MPa pressure. Three low pressure pre-heaters and four high pressure pre-heaters are foreseen to achieve the envisaged reactor inlet temperature of 280 deg. C at full load. A feedwater tank of 603 m{sup 3} at 0.55 MPa pressure serves as an accumulator for normal and accidental conditions. The steam cycle has been modelled with APROS, developed by VTT Finland, to provide thermodynamic data and cycle efficiency values under full load and part load operation conditions as well as the transient response to load changes. A plant control system has been designed in which the reactor inlet pressure is controlled by the turbine valve, the reactor power is controlled by the feedwater pumps while the life steam temperature is controlled by control rods, and the reheat temperature is controlled by the reheater valve. Neglecting the reactivity control, the core power can also be treated as input parameter such that the life steam temperature is directly controlled by the feedwater mass flow. The plant control can handle all loading and de-loading cycles including complete shut down. A constant pressure at reactor inlet is foreseen for all load cases. Peak temperatures of the fuel pins are checked with a simplified core model. Two shut down procedures starting at 50% load are presented. A reactor scram with turbine states the safe shut down of the whole plant. To avoid hard material temperature changes, a controlled shut down procedure is designed. The rotational speed of the

  5. Investigation of the Corrosion and Scaling Potentials of Raw and Treated Water and Its Effect on Concrete Tanks at Al-Tayyaraa Water Treatment Plant

    Directory of Open Access Journals (Sweden)

    Layla Abdulkareem Mokif

    2018-01-01

    Full Text Available This study is conducted to evaluate corrosion and scaling potentials of raw and treated water at Al-Tayyaraa water treatment plant during a period of twelve months, starting from January to December 2016. Three indices of corrosion and scaling in this study are considered including Ryznar Index (RI, Langelier Saturation Index (LSI, and Aggressive Index (AI. Water quality parameters pH, Alk, (Ca, temperature, calcium as CaCO3, and (TDS are measured. For raw water, the values of LSI and RI are (0.14-0.504 and (6.956 -7.62, respectively, whereas for treated water, the values of LSI and RI are (0.03-0.4 and (7.02-7.7, respectively. The values of AI are (11.77-12 for raw water and (11.67-11.948 for treated water. The calculated values of Langelier Saturation Index (LSI reveal that the treated and raw water are balanced to some faint coating (light scale forming. The values of RI point that the raw and treated water are corrosive and values of aggressive index show that the water is moderate corrosion and no obvious effect on concrete tank at water treatment plants.

  6. Why Do People Stop Treating Contaminated Drinking Water with Solar Water Disinfection (SODIS)?

    Science.gov (United States)

    Tamas, Andrea; Mosler, Hans-Joachim

    2011-01-01

    Solar Water Disinfection (SODIS) is a simple method designed to treat microbiologically contaminated drinking water at household level. This article characterizes relapse behavior in comparison with continued SODIS use after a 7-month nonpromotion period. In addition, different subtypes among relapsers and continuers were assumed to diverge mainly…

  7. Towards intrinsically safe light-water reactors

    Energy Technology Data Exchange (ETDEWEB)

    Hannerz, K

    1983-07-01

    Most of the present impediments to the rational use of the nuclear option have their roots in the reactor safety issue. The approach taken to satisfy the escalating safety concerns has resulted in excessively complex and expensive plant designs but has failed to create public confidence. This paper describes a new approach based on the principle of Process Inherent Ultimate Safety (PIUS). With the PIUS principle, ultimate safety is obtained by guaranteeing core integrity under all credible conditions. This is accomplished on the basis of the laws of gravity and thermohydraulics alone, interacting with the heat extraction process in an intact or damaged primary circuit, without recourse to engineered safety systems that may fail or dependence on error-prone human intervention. Application of the PIUS principle to the pressurized water reactor involves a substantial redesign of the reactor and primary system but builds on established PWR technology where long-term operation is needed for verification.

  8. Towards intrinsically safe light-water reactors

    International Nuclear Information System (INIS)

    Hannerz, K.

    1983-07-01

    Most of the present impediments to the rational use of the nuclear option have their roots in the reactor safety issue. The approach taken to satisfy the escalating safety concerns has resulted in excessively complex and expensive plant designs but has failed to create public confidence. This paper describes a new approach based on the principle of Process Inherent Ultimate Safety (PIUS). With the PIUS principle, ultimate safety is obtained by guaranteeing core integrity under all credible conditions. This is accomplished on the basis of the laws of gravity and thermohydraulics alone, interacting with the heat extraction process in an intact or damaged primary circuit, without recourse to engineered safety systems that may fail or dependence on error-prone human intervention. Application of the PIUS principle to the pressurized water reactor involves a substantial redesign of the reactor and primary system but builds on established PWR technology where long-term operation is needed for verification

  9. Corrosion problems in light water nuclear reactors

    International Nuclear Information System (INIS)

    Berry, W.E.

    1984-01-01

    The corrosion problems encountered during the author's career are reviewed. Attention is given to the development of Zircaloys and attendant factors that affect corrosion; the caustic and chloride stress corrosion cracking (SCC) of austenitic stainless steel steam generator tubing; the qualification of Inconel Alloy 600 for steam generator tubing and the subsequent corrosion problem of secondary side wastage, caustic SCC, pitting, intergranular attack, denting, and primary side SCC; and SCC in weld and furnace sensitized stainless steel piping and internals in boiling water reactor primary coolants. Also mentioned are corrosion of metallic uranium alloy fuels; corrosion of aluminum and niobium candidate fuel element claddings; crevice corrosion and seizing of stainless steel journal-sleeve combinations; SCC of precipitation hardened and martensitic stainless steels; low temperature SCC of welded austenitic stainless steels by chloride, fluoride, and sulfur oxy-anions; and corrosion problems experienced by condensers

  10. Optimum refuelling strategy in light water reactors

    International Nuclear Information System (INIS)

    Hermansky, B.

    1977-01-01

    The flow sheets are presented of refuelling schedules aimed at obtaining deep average fuel burnup with levelling up the output along the reactor radius in large PWR reactors. The zone refuelling is described in which only 1/3 of the fuel element number is replaced. The elements are placed in the outer zone of the core. Also described is the distributed refuelling in which fuel elements with different burnups are evenly spaced. A modified refuelling schedule is shown involving the replacement from the outside to the inside where a uniform radial distribution of thermal output is achieved. Calculation methods are shown of determining the optimum refuelling strategy. Dynamic programming is one of the prospective computer methods. Its general algorithm is indicated. A survey is made of some studies on the optimum refuelling strategy in pressurized water reactors. (J.B.)

  11. Safety aspects of water chemistry in light water reactors

    International Nuclear Information System (INIS)

    1988-12-01

    The goals of the water chemistry control programmes are to maximize operational safety and the availability and operating life of primary system components, to maximize fuel integrity, and to control radiation buildup. To achieve these goals an effective corporate policy should be developed and implemented. Essential management responsibilities are: Recognizing of the long-term benefits of avoiding or minimizing: a) system corrosion; b) fuel failure; and c) radiation buildup. The following control or diagnostic parameters are suitable performance indicators: for PWR primary coolant circuits: pH of reactor water (by operating temperature); Concentration of chlorides in reactor water; Hydrogen (or oxygen) in reactor water. For PWR secondary coolant circuits: pH in feedwater; Cation productivity in steam generator blowdown; Iron concentration in feedwater; Oxygen concentration in condensate. And BWR coolant circuits: Conductivity of reactor water; Concentration of chlorides in reactor water; Iron concentration in feedwater; Copper concentration in feedwater. The present document represents a review of the developments in some Member States on how to implement a reasonable water chemistry programme and how to assess its effectiveness through numerical indicators. 12 figs, 20 tabs

  12. Neutron fluence determination for light water reactor pressure vessels

    International Nuclear Information System (INIS)

    Gold, R.

    1994-01-01

    A general description of limitations that exist in pressure vessel neutron fluence determinations for commercial light water reactors is presented. Complexity factors that arise in light water reactor pressure vessel neutron fluence calculations are identified and used to analyze calculational limitations. Two broad categories of calculational limitations are introduced, namely benchmark field limitations and deep penetration limitations. Explicit examples of limitations that can arise in each of these two broad categories are presented. These limitations are used to show that the recent draft regulatory guide for the determination of pressure vessel neutron fluence, developed by the Nuclear Regulatory Commission, is based upon procedures and assumptions that are not valid. To eliminate the complexity and limitations of calculational methods, it is recommended that the determination of light water reactor pressure vessel neutron fluence be based upon experiment. Recommendations for improved methods of pressure vessel surveillance neutron dosimetry are advanced

  13. Ultraviolet light: sterile water without chlorine smell and taste

    International Nuclear Information System (INIS)

    Anon.

    1977-01-01

    The use of chlorine and hypochlorite is necessary in larger waterworks, but it is a disadvantage in smaller plants, where overtreatment easily leads to smell and taste of chlorine in the water. Ultraviolet light with a wavelength of 2535 Angstrom gives 100% disinfection with a dose of 10 mWs/cm 2 for all known bacteria. In practice a dose of 40 mWs/cm 2 and an irradiation time of 15 minutes is desireable. A standard unit utilising six UV light tubes arranged concentrically around a quartz tube, through which the water flows, is described briefly. (JIW)

  14. 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.

  15. TREAT Neutronics Analysis of Water-Loop Concept Accommodating LWR 9-rod Bundle

    Energy Technology Data Exchange (ETDEWEB)

    Hill, Connie M.; Woolstenhulme, Nicolas E.; Parry, James R.; Bess, John D.; Housley, Gregory K.

    2016-09-01

    Abstract. Simulation of a variety of transient conditions has been successfully achieved in the Transient Reactor Test (TREAT) facility during operation between 1959 and 1994 to support characterization and safety analysis of nuclear fuels and materials. A majority of previously conducted tests were focused on supporting sodium-cooled fast reactor (SFR) designs. Experiments evolved in complexity. Simulation of thermal-hydraulic conditions expected to be encountered by fuels and materials in a reactor environment was realized in the development of TREAT sodium loop experiment vehicles. These loops accommodated up to 7-pin fuel bundles and served to simulate more closely the reactor environment while safely delivering large quantities of energy into the test specimen. Some of the immediate TREAT restart operations will be focused on testing light water reactor (LWR) accident tolerant fuels (ATF). Similar to the sodium loop objectives, a water loop concept, developed and analyzed in the 1990’s, aimed at achieving thermal-hydraulic conditions encountered in commercial power reactors. The historic water loop concept has been analyzed in the context of a reactivity insertion accident (RIA) simulation for high burnup LWR 2-pin and 3-pin fuel bundles. Findings showed sufficient energy could be deposited into the specimens for evaluation. Similar results of experimental feasibility for the water loop concept (past and present) have recently been obtained using MCNP6.1 with ENDF/B-VII.1 nuclear data libraries. The old water loop concept required only two central TREAT core grid spaces. Preparation for future experiments has resulted in a modified water loop conceptual design designated the TREAT water environment recirculating loop (TWERL). The current TWERL design requires nine TREAT core grid spaces in order to place the water recirculating pump under the TREAT core. Due to the effectiveness of water moderation, neutronics analysis shows that removal of seven additional

  16. Review of advanced methods for treating radioactive contaminated water

    International Nuclear Information System (INIS)

    Dubourg, M.

    2002-01-01

    The accidental release of large quantities of radionuclide after a nuclear accident tends to contaminate the groundwater system of rivers and lakes by the transfer of the main radionuclides such as Cesium 137, Strontium 90 or Cobalt 60, Ruthenium 106 and others (including transuranic radionuclides, such as: Pu 239, Pu 240, Am 241..). The aim of this paper is to review the possible solutions for the removal of these contaminants from large quantities of water. the use of crown ethers for the selective removal of strontium 90 such as the di-cyclohexyl 18 crown 6 which is able to remove with 90% of efficiency the strontium. the use of zeolites for the removal of Cesium 137. On larger scale the use of electromagnetic filtration technology is able to process in a relatively short time large quantities of water by using a seeding system of resin coated metallic magnetic particles to enhance the filtering efficiency under cold conditions. Examples of efficiencies and results obtained on loops at a fairly large will be given in this paper, theses examples show rather high efficiency of removal even at low concentration of contaminants (a few ppb: part per billion). Examples of water treatment concepts will be also given for treatment of contaminated surface water and to treat large groundwater applications. Major applications could be implemented on various sites namely in Russia (Karatchai lake) or in Belarus and Ukraine. The magnetic filtration is not a new concept but with the use of various selective adsorbing treatment particles, this concept has been proven so effective that dissolved metals in process water have been reduced to level in the very low ppb range. (authors)

  17. Loose parts monitoring in light water reactor cooling systems

    International Nuclear Information System (INIS)

    Santos, A.; Alma, B.J.

    1982-01-01

    The work related to loose monitoring system for light water reactor, developed at GRS - Munique, are described. The basic problems due to the exact localization and detection of the loose part as well the research activities and development necessary aiming to obtain the best techniques in this field. (E.G.) [pt

  18. Overview of environmental materials degradation in light-water reactors

    International Nuclear Information System (INIS)

    Shaaban, H.I.; Wu, P.

    1986-08-01

    This report provides a brief overview of analyses and conclusions reported in published literature regarding environmentally induced degradation of materials in operating light-water reactors. It is intended to provide a synopsis of subjects of concern rather than to address a licensing basis for any newly discovered problems related to reactor materials

  19. European community light water reactor safety research projects. Experimental issue

    International Nuclear Information System (INIS)

    1975-01-01

    Research programs on light water reactor safety currently carried out in the European Community are presented. They cover: accident conditions (LOCA, ECCS, core meltdown, external influences, etc...), fault and accident prevention and means of mitigation, normal operation conditions, on and off site implications and equipment under severe accident conditions, and miscellaneous subjects

  20. Tritium formation and elimination in light-water reactors

    International Nuclear Information System (INIS)

    Dolle, L.; Briec, M.; Miquel, P.

    1976-01-01

    Light-water reactors have a tritium balance which should be considered from both the working constraint and environmental pollution aspects. The formation of tritium in the primary circuit and in the fuel, the elimination and enrichment processes are considered [fr

  1. utilization of some agricultural wastes in treating water pollutants

    International Nuclear Information System (INIS)

    Gad, H.M.H.H.

    2003-01-01

    Rice husks, a locally available agricultural by-product, were investigated with aim of producing good adsorbing materials suitable for remediating water pollution . Raw lignocellulose was treated through various procedures: simple carbonization to high temperature, pyrolysis under flowing steam at moderate temperatures and chemical activation with H 3 PO 4 followed by pyrolysis at moderate temperature . A partially deashed precursor was obtained by boiling in alkali solution, thereafter botanical residue was steam activated at a single temperature, and leachate acidified whereby silica was precipitated, many types of adsorbents were thus derived: chars, activated carbon and silica. the obtained various categories of sorbents were characterized by different techniques to asses their physico-chemical and adsorptive properties . this involved: ash content, thermogravimetry, FTIR, electron microscopy, N 2 gas adsorption at 77 k and adsorption capacity from solution using probe molecules

  2. Microbial water quality of treated water and raw water sources in the ...

    African Journals Online (AJOL)

    2015-10-05

    Oct 5, 2015 ... study investigated microbial water quality and the impact of microbial water quality related disasters in the area supplied by the Morton ... water sources state that water used for domestic purposes should not be contain than 100 CFU/mℓ. ... water should be appealing in terms of colour, smell and taste.

  3. Blood flow in transplantable bladder tumors treated with hematoporphyrin derivative and light

    International Nuclear Information System (INIS)

    Selman, S.H.; Kreimer-Birnbaum, M.; Klaunig, J.E.; Goldblatt, P.J.; Keck, R.W.; Britton, S.L.

    1984-01-01

    Following hematoporphyrin derivative (HPD) photochemotherapy, blood flow to transplantable N-[4-(5-nitro-2-furyl)-2-thia-zolyl] formamide-induced urothelial tumors was determined by a radioactive microsphere technique using either 103 Ru or 141 Ce. Two tumors were implanted s.c. on the abdominal wall of Fischer 344 weanling rats. HPD (10 mg/kg body weight) was administered 24 hr prior to phototherapy (red light, greater than 590 nm; 360 J/sq cm). One of the two tumors was shielded from light exposure and served as an internal control. Blood flows were determined in control animals that received no treatment (Group 1), HPD only (Group 2), or light only (Group 3). In Groups 4 and 5, animals received the combination of HPD and light but differed in the time interval between treatment and blood flow determinations (10 min and 24 hr, respectively). Only blood flow to tumors treated with HPD and light showed a significant decrease (p less than 0.05) when compared with their internal controls both at 10 min (Group 4) and 24 hr (Group 5) after completion of phototherapy. These studies suggest that disruption of tumor blood flow may be an important mechanism of action of this method of cancer therapy

  4. Predicting spectral and PAR light attenuation in Greenlandic coastal waters

    DEFF Research Database (Denmark)

    Murray, Ciarán; Markager, Stiig; Stedmon, Colin

    The spectral quality and penetration of light are key parameters controlling the productivity of Greenlandic fjords. Solar elevation and sea ice play an important role, but during the increasing ice free period and summer months in particular, light is also regulated by water constituents. We...... (CDOM), phytoplankton pigments and inorganic particles. These differences are due in part to hydrography and to the sources of meltwater: respectively, fjord-terminating and land-terminating glaciers. We present a model to explain the variation in spectral and PAR irradiance in terms of the variation...

  5. Microbial water quality of treated water and raw water sources in the ...

    African Journals Online (AJOL)

    Microbial water quality is an essential aspect in the provision of potable water for domestic use. The provision of adequate amounts of safe water for domestic purposes has become difficult for most municipalities mandated to do so in Zimbabwe. Morton-Jaffray Treatment Plant supplies potable water to Harare City and ...

  6. Self-propagating solar light reduction of graphite oxide in water

    Energy Technology Data Exchange (ETDEWEB)

    Todorova, N.; Giannakopoulou, T.; Boukos, N.; Vermisoglou, E. [Institute of Nanoscience and Nanotechnology, NCSR “Demokritos”, 153 41 Attikis (Greece); Lekakou, C. [Division of Mechanical, Medical, and Aerospace Engineering, Faculty of Engineering and Physical Sciences, University of Surrey, Guildford (United Kingdom); Trapalis, C., E-mail: c.trapalis@inn.demokritos.gr [Institute of Nanoscience and Nanotechnology, NCSR “Demokritos”, 153 41 Attikis (Greece)

    2017-01-01

    Highlights: • Graphite oxide was partially reduced by solar light irradiation in water media. • No addition of catalysts nor reductive agent were used for the reduction. • Specific capacitance increased stepwise with increase of irradiation time. • Self-propagating reduction of graphene oxide by solar light is suggested. - Abstract: Graphite Oxide (GtO) is commonly used as an intermediate material for preparation of graphene in the form of reduced graphene oxide (rGO). Being a semiconductor with tunable band gap rGO is often coupled with various photocatalysts to enhance their visible light activity. The behavior of such rGO-based composites could be affected after prolonged exposure to solar light. In the present work, the alteration of the GtO properties under solar light irradiation is investigated. Water dispersions of GtO manufactured by oxidation of natural graphite via Hummers method were irradiated into solar light simulator for different periods of time without addition of catalysts or reductive agent. The FT-IR analysis of the treated dispersions revealed gradual reduction of the GtO with the increase of the irradiation time. The XRD, FT-IR and XPS analyses of the obtained solid materials confirmed the transition of GtO to rGO under solar light irradiation. The reduction of the GtO was also manifested by the CV measurements that revealed stepwise increase of the specific capacitance connected with the restoration of the sp{sup 2} domains. Photothermal self-propagating reduction of graphene oxide in aqueous media under solar light irradiation is suggested as a possible mechanism. The self-photoreduction of GtO utilizing solar light provides a green, sustainable route towards preparation of reduced graphene oxide. However, the instability of the GtO and partially reduced GO under irradiation should be considered when choosing the field of its application.

  7. Assessment of the high performance light water reactor concept

    Energy Technology Data Exchange (ETDEWEB)

    Starflinger, J. [Univ. of Stuttgart, IKE, (Germany); Schulenberg, T. [Karlsruhe Inst. of Tech., Karlsruhe (Germany); Bittermann, D. [AREVA NP GmbH, Erlangen (Germany); Andreani, M. [Paul Scherrer Inst., Villigen (Switzerland); Maraczy, C. [AEKI-KFKI, Budapest (Hungary)

    2011-07-01

    From 2006-2010, the High Performance Light Water Reactor (HPLWR) was investigated within a European Funded project called HPLWR Phase 2. Operated at 25MPa with a heat-up rate in the core from 280{sup o}C to 500{sup o}C, this reactor concept provides a technological challenge in the fields of design, neutronics, thermal-hydraulics and heat transfer, materials, and safety. The assessment of the concept with respect to the goals of the technology roadmap for Generation IV Nuclear Reactors of the Generation IV International Forum shows that the HPLWR has a potential to fulfil the goals of economics, safety and proliferation resistance and physical protection. In terms of sustainability, the HPLWR with a thermal neutron spectrum investigated within this project, does not differ from existing Light Water Reactors in terms of usage of fuel and waste production. (author)

  8. Assessment of light water reactor accident management programs and experience

    International Nuclear Information System (INIS)

    Hammersley, R.J.

    1992-03-01

    The objective of this report is to provide an assessment of the current light water reactor experience regarding accident management programs and associated technology developments. This assessment for light water reactor (LWR) designs is provided as a resource and reference for the development of accident management capabilities for the production reactors at the Savannah River Site. The specific objectives of this assessment are as follows: 1. Perform a review of the NRC, utility, and industry (NUMARC, EPRI) accident management programs and implementation experience. 2. Provide an assessment of the problems and opportunities in developing an accident management program in conjunction or following the Individual Plant Examination process. 3. Review current NRC, utility, and industry technological developments in the areas of computational tools, severe accident predictive tools, diagnostic aids, and severe accident training and simulation

  9. Light water breeder reactor using a uranium-plutonium cycle

    International Nuclear Information System (INIS)

    Radkowsky, A.; Chen, R.

    1990-01-01

    This patent describes a light water receptor (LWR) for breeding fissile material using a uranium-plutonium cycle. It comprises: a prebreeder section having plutonium fuel containing a Pu-241 component, the prebreeder section being operable to produce enriched plutonium having an increased Pu-241 component; and a breeder section for receiving the enriched plutonium from the prebreeder section, the breeder section being operable for breeding fissile material from the enriched plutonium fuel. This patent describes a method of operating a light water nuclear reactor (LWR) for breeding fissile material using a uranium-plutonium cycle. It comprises: operating the prebreeder to produce enriched plutonium fuel having an increased Pu-241 component; fueling a breeder section with the enriched plutonium fuel to breed the fissile material

  10. Analysis of an accelerator-driven subcritical light water reactor

    International Nuclear Information System (INIS)

    Kruijf, W.J.M. de; Wakker, P.H.; Wetering, T.F.H. van de; Verkooijen, A.H.M.

    1997-01-01

    An analysis of the basic characteristics of an accelerator-driven light water reactor has been made. The waste in the nuclear fuel cycle is considerably less than in the light water reactor open fuel cycle. This is mainly caused by the use of equilibrium nuclear fuel in the reactor. The accelerator enables the use of a fuel composition with infinite multiplication factor k ∞ < 1. The main problem of the use of this type of fuel is the strongly peaked flux distribution in the reactor core. A simple analytical model shows that a large core is needed with a high peak power factor in order to generate net electric energy. The fuel in the outer regions of the reactor core is used very poorly. 7 refs., 4 figs., 1 tab

  11. Uranium utilization of light water cooled reactors and fast breeders

    International Nuclear Information System (INIS)

    Stojadinovic, Timm

    1991-08-01

    The better uranium utilization of fast breeder reactors as compared with water cooled reactors is one argument in favour of the breeder introduction. This report tries to quantify this difference. It gives a generally valid formalism for the uranium utilization as a function of the fuel burnup, the conversion rate, fuel cycle losses and the fuel enrichment. On the basis of realistic assumptions, the ratio between the utilizations of breeder reactors to that of light water cooled reactors (LWR) amounts to 180 for the open LWR cycle and 100 in case of plutonium recycling in LWRs

  12. Recurrent syncope and cardiac arrest in a patient with systemic light chain amyloidosis treated with bortezomib

    Directory of Open Access Journals (Sweden)

    Navin Jaipaul

    2016-05-01

    Full Text Available About 10-15% of patients with multiple myeloma develop light chain (AL amyloidosis. AL amyloidosis is a systemic disease that may involve multiple organs, often including the heart. It may present clinically with bradyarrhythmia and syncope. The proteasome inhibitor bortezomib has been used with clinical efficacy in treating patients with AL amyloidosis but also implicated as a possible cause of cardiomyocyte injury. We report a case of a 48-year-old man with AL amyloidosis and increased frequency of syncope and cardiac arrest after starting bortezomib. The biologic and clinical plausibility of a heightened risk for cardiac arrest in patients with cardiac AL amyloidosis and history of syncope being treated with bortezomib is a possibility that is not well documented in the medical literature and warrants further investigation.

  13. Nuclear Data Libraries for Hydrogen in Light Water Ice

    International Nuclear Information System (INIS)

    Torres, L; Gillette, V.H

    2000-01-01

    Nuclear data libraries were produced for hydrogen (H) in light water ice at different temperatures, 20, 30, 50, 77, 112, 180, 230 K.These libraries were produced using the NJOY nuclear data processing system.With this code we produce pointwise cross sections and related quantities, in the ENDF format, and in the ACE format for MCNP.Experimental neutron spectra at such temperatures were compared with MCNP4B simulations, based on the locally produced libraries, leading to satisfactory results

  14. Coatings used in light-water nuclear power plants

    International Nuclear Information System (INIS)

    Anon.

    1981-01-01

    The guide is intended to provide a common basis in the selection of test methods which may be required to evaluate and qualify protective coatings (paints) to be used in a light-water nuclear power plant. Standard test methods for the determination of fire resistance, chemical resistance, physical properties, effects of radiation, decontaminability, thermal conductivity, repairability, and for evaluation under accident conditions are included

  15. Water quality improvement of treated wastewater by intermittent soil percolation.

    Science.gov (United States)

    Castillo, G; Mena, M P; Dibarrart, F; Honeyman, G

    2001-01-01

    Our research aimed to evaluate intermittent soil infiltration of treated sewage for reuse in the north of Chile. Aerated lagoon effluent was infiltrated in columns packed with native soils (sandy-lime, lime-gravel and limey-sand). Columns were operated for more than a year under different cycles of filling and drying, depths and load pressures depending on soil characteristics. The efficiency of the system was determined through influent-effluent microbiological indicators level (faecal coliforms, E. coli, Salmonella spp, MS2 phage, and protozoan cysts), physicochemical characterisation (TOC, COD, BOD, nitrogen), and hydraulic flow measurement. Results showed: (a) high reduction of enteric bacteria (5-7 log10), some inactivation of phage (2-4 log10) and complete removal of intestinal cyst; (b) stable removal of organic matter (80-90% reduction of TOC, COD, BOD); and (c) partial ammonia reduction through adsorption and nitrification with denitrification mainly occurring in sandy soil. Preliminary data from pilot plant working in the field showed better results that those obtained in the laboratory especially removal of microbiological indicators. Microbiological quality of effluent met Class A regulations for agricultural reuse (WHO, 1989) and the system looks like an attractive alternative to cope with water shortage in the region.

  16. A process for treating radioactive water-reactive wastes

    International Nuclear Information System (INIS)

    Dziewinski, J.; Lussiez, G.; Munger, D.

    1995-01-01

    Los Alamos National Laboratory and other locations in the complex of experimental and production facilities operated by the United States Department of Energy (DOE) have generated an appreciable quantity of hazardous and radioactive wastes. The Resource Conservation and Recovery Act (RCRA) enacted by the United States Congress in 1976 and subsequently amended in 1984, 1986, and 1988 requires that every hazardous waste must be rendered nonhazardous before disposal. Many of the wastes generated by the DOE complex are both hazardous and radioactive. These wastes, called mixed wastes, require applying appropriate regulations for radioactive waste disposal and the regulations under RCRA. Mixed wastes must be treated to remove the hazardous waste component before they are disposed as radioactive waste. This paper discusses the development of a treatment process for mixed wastes that exhibit the reactive hazardous characteristic. Specifically, these wastes react readily and violently with water. Wastes such as lithium hydride (LiH), sodium metal, and potassium metal are the primary wastes in this category

  17. Effects of Intentionally Treated Water on Growth of Arabidopsis thaliana Seeds with Cryptochrome Mutations.

    Science.gov (United States)

    Shiah, Yung-Jong; Hsieh, Hsu-Liang; Chen, Huai-Ju; Radin, Dean I

    A previous experiment suggested that consumption of intentionally treated tea influenced subjective mood under double-blind, controlled conditions. To investigate that effect objectively, again under double-blind, controlled conditions, we studied whether Arabidopsis thaliana seeds hydrated with intentionally treated vs. untreated water would show differences in hypocotyl length, anthocyanin, and chlorophyll. Three Buddhist monks focused their intention on commercially bottled water with the goal of improving the growth of seeds; bottled water from the same source served as an untreated control. Seeds with the following three variations of cryptochrome (CRY) were used: the wild type Arabidopsis (Columbia-4), a gain-of-function mutation (His-CRY2), and a loss-of function mutation (cry1/2), where "gain" and "loss" refer to enhanced and reduced sensitivity to blue light, respectively. Seeds were hydrated with treated or untreated water under blinded conditions, and then placed in random positions in an incubator. The germination process was repeated three times in each experiment, each time using new seeds, and then the entire experiment was repeated four times. Data combined across the four experiments showed a significant decrease in hypocotyl length in the His-CRY2 seedlings (treated mean 1.31 ± 0.01mm, untreated mean 1.43 ± 0.01mm, P < 10 -13 ), a significant increase in anthocyanin with all three forms of cry, particularly His-CRY2 (treated mean 17.0 ± 0.31mg, untreated mean 14.5 ± 0.31mg, P < 10 -4 ), and a modest increase in chlorophyll in His-CRY2 (treated mean 247.6 ± 5.63mg, untreated mean 230.6 ± 5.63mg, P = .05). These outcomes conformed to the monks' intentions because a decrease in hypocotyl length and increase in anthocyanin and chlorophyll are associated with enhanced photomorphogenic growth. These experiments suggest that the His-CRY2 mutation of Arabidopsis may be an especially robust "detector" of intention. Copyright © 2017 Elsevier Inc. All

  18. Design concept of the high performance light water reactor

    Energy Technology Data Exchange (ETDEWEB)

    Schulenberg, Thomas; Starflinger, Joerg [Forschungszentrum Karlsruhe GmbH Technik und Umwelt (Germany). Inst. for Nuclear and Energy Technologies; Bittermann, Dietmar [AREVA NP GmbH, Erlangen (Germany). NEP-G Process

    2009-04-15

    The 'High Performance Light Water Reactor' (HPLWR) is a Light Water Reactor operating with supercritical water as coolant. At a pressure of 25 MPa in the core, water is heated up from 280 to 500 C. For these conditions, the envisaged net plant efficiency is 43.5%. The core design concept is based on a so-called '3-pass-core' in which the coolant is heated up in three subsequent steps. After each step, the coolant is mixed avoiding hot streaks possibly leading to unacceptable wall temperatures. The design of such a core comprises fuel assemblies containing 40 fuel rods and an inner and outer box for a better neutron moderation. Nine of these are assembled to a cluster with common head- and foot piece. The coolant is mixed inside an upper and inside a lower mixing chamber and leaves the reactor pressure vessel through a co-axial pipe, which protects the vessel wall against too high temperatures. (orig.)

  19. Dual-purpose light water reactor supplying heat for desalination

    International Nuclear Information System (INIS)

    Waplington, G.; Fichtner, H.

    1978-01-01

    The technical as well as the economic aspects of using a large commercial light water reactor for the production of both electricity and potable water have been examined. For the basis of the study, the multistage flash distillation process was selected, in conjunction with a reactor rated at not less than 2100 MW (thermal). Combined use of a condensing and a back-pressure turbine (the latter matched to distillation plant steam requirements) represents a convenient method for supplying process heat. Overall costs can be fairly allocated to the two products using the ''power credit'' method. A sample economic evaluation indicates highly favorable water costs as compared with more conventional distillation schemes based on fossil fuel

  20. Critical heat flux experiments in a circular tube with heavy water and light water. (AWBA Development Program)

    International Nuclear Information System (INIS)

    Williams, C.L.; Beus, S.G.

    1980-05-01

    Experiments were performed to establish the critical heat flux (CHF) characteristics of heavy water and light water. Testing was performed with the up-flow of heavy and of light water within a 0.3744 inch inside diameter circular tube with 72.3 inches of heated length. Comparisons were made between heavy water and light water critical heat flux levels for the same local equilibrium quality at CHF, operating pressure, and nominal mass velocity. Results showed that heavy water CHF values were, on the average, 8 percent below the light water CHF values

  1. Evaluation of coagulation factors in fresh frozen plasma treated with riboflavin and ultraviolet light

    Directory of Open Access Journals (Sweden)

    Antić Ana

    2012-01-01

    Full Text Available Background/Aim. Pathogen inactivation in blood products using riboflavin and ultraviolet (UV light represents a proactive approach to blood safety, not only for known infectious agents but also for new ones or not yet recognized as threats to the blood supply. This method inactivates a virus, bacteria, fungus, or protozoan pathogen from the blood product without damaging its function or shelf-life. The aim of the study was to study the influence of photoinactivation using riboflavin on the concentration of coagulation factors and coagulation inhibitors in plasma that was treated before freezing. Methods. The examination included 30 units of plasma, separated from whole blood donated by voluntary blood donors around 6 h from the moment of collection. They were treated by riboflavin (35 mL and UV rays (6.24 J/mL, 265-370 nm on Mirasol aparature (Caridian BCT Biotechnologies, USA in approximate duration of 6 min. The samples for examining were taken before (K - control units and after illumination (I - illuminated units. Results. Comparing the middle values of coagulation factors in the control and illuminated units we noticed their statistically significant decrease in illuminated units (p < 0.001, but the activity of coagulation ones was still in the reference range. The most sensitive coagulation factors to photoinactivation were FVIII, FIX and FXI (21.99%, 20.54% and 17.26% loss, respectively. Anticoagulant factors were better preseved than coagulation factors. Conclusion. Plasma separated from whole blood donation within 6 h, treated with riboflavin and UV light within 6 h from separation and frozen at temperature below -30ºC within 24 h, shows good retention of pro- and anticoagulation activity.

  2. Aging management of major light water reactor components

    International Nuclear Information System (INIS)

    Shah, V.N.; Sinha, U.P.; Ware, A.G.

    1992-01-01

    Review of technical literature and field experience has identified stress corrosion cracking as one of the major degradation mechanisms for the major light water reactor components. Three of the stress corrosion cracking mechanisms of current concern are (a) primary water stress corrosion cracking (PWSCC) in pressurized water reactors, and (b) intergranular stress corrosion cracking (IGSCC) and (c) irradiation-assisted stress corrosion cracking (IASCC) in boiling water reactors. Effective aging management of stress corrosion cracking mechanisms includes evaluation of interactions between design, materials, stressors, and environment; identification and ranking of susceptible sites; reliable inspection of any damage; assessment of damage rate; mitigation of damage; and repair and replacement using corrosion-resistant materials. Management of PWSCC includes use of lower operating temperatures, reduction in residual tensile stresses, development of reliable inspection techniques, and use of Alloy 690 as replacement material. Management of IGSCC of nozzle and attachment welds includes use of Alloy 82 as weld material, and potential use of hydrogen water chemistry. Management of IASCC also includes potential use of hydrogen water chemistry

  3. Computational fluid dynamics simulations of light water reactor flows

    International Nuclear Information System (INIS)

    Tzanos, C.P.; Weber, D.P.

    1999-01-01

    Advances in computational fluid dynamics (CFD), turbulence simulation, and parallel computing have made feasible the development of three-dimensional (3-D) single-phase and two-phase flow CFD codes that can simulate fluid flow and heat transfer in realistic reactor geometries with significantly reduced reliance, especially in single phase, on empirical correlations. The objective of this work was to assess the predictive power and computational efficiency of a CFD code in the analysis of a challenging single-phase light water reactor problem, as well as to identify areas where further improvements are needed

  4. Nuclear safety in light water reactors severe accident phenomenology

    CERN Document Server

    Sehgal, Bal Raj

    2011-01-01

    This vital reference is the only one-stop resource on how to assess, prevent, and manage severe nuclear accidents in the light water reactors (LWRs) that pose the most risk to the public. LWRs are the predominant nuclear reactor in use around the world today, and they will continue to be the most frequently utilized in the near future. Therefore, accurate determination of the safety issues associated with such reactors is central to a consideration of the risks and benefits of nuclear power. This book emphasizes the prevention and management of severe accidents to teach nuclear professionals

  5. Automated ultrasonic examination of light water reactor systems

    International Nuclear Information System (INIS)

    Walter, J.H.

    1975-01-01

    An automated ultrasonic examination system has been developed to meet the pre- and inservice inspection requirements of light water reactors. This system features remotely-controlled travelling instrument carriers, computerized collection and storage or inspection data in a manner providing real time comparison against code standards, and computer control over the positioning of the instrument carriers to provide precise location data. The system is currently being utilized in the field for a variety of reactor inspections. The principal features of the system and the recent inspection experience are discussed. (author)

  6. Spent fuel data base: commercial light water reactors. [PWR; BWR

    Energy Technology Data Exchange (ETDEWEB)

    Hauf, M.J.; Kniazewycz, B.G.

    1979-12-01

    As a consequence of this country's non-proliferation policy, the reprocessing of spent nuclear fuel has been delayed indefinitely. This has resulted in spent light water reactor (LWR) fuel being considered as a potential waste form for disposal. Since the Nuclear Regulatory Commission (NRC) is currently developing methodologies for use in the regulation of the management and disposal of high-level and transuranic wastes, a comprehensive data base describing LWR fuel technology must be compiled. This document provides that technology baseline and, as such, will support the development of those evaluation standards and criteria applicable to spent nuclear fuel.

  7. Properties of light water reactor spent fuel cladding. Interim report

    International Nuclear Information System (INIS)

    Farwick, D.G.; Moen, R.A.

    1979-08-01

    The Commercial Waste and Spent Fuel Packaging Program will provide containment packages for the safe storage or disposal of spent Light Water Reactor (LWR) fuel. Maintaining containment of radionuclides during transportation, handling, processing and storage is essential, so the best understanding of the properties of the materials to be stored is necessary. This report provides data collection, assessment and recommendations for spent LWR fuel cladding materials properties. Major emphasis is placed on mechanical properties of the zircaloys and austenitic stainless steels. Limited information on elastic constants, physical properties, and anticipated corrosion behavior is also provided. Work is in progress to revise these evaluations as the program proceeds

  8. Determination of oestrogen hormones in raw and treated water ...

    African Journals Online (AJOL)

    Hormones in water samples have been classified as 'emerging pollutants' and may pose a potential risk for humans. Hormones can be found in both surface and ground water at low concentrations. These compounds enter water streams through wastewater treatment plants (WWTP) and may elicit endocrine disruption to ...

  9. Bacteriological and Physcio – Chemical Evaluation of Water Treated ...

    African Journals Online (AJOL)

    Bacteriological and physico-chemical evaluation of water coagulated with Moringa oleifera seed powder preparations on Challawa river water intake station was conducted for a period of ... The implications of the results are discussed in relation to water sanitation and human health and some recommendations presented.

  10. chemical evaluation of water treated with seed powder of moringa ...

    African Journals Online (AJOL)

    DR. AMIN

    2011-12-02

    Dec 2, 2011 ... Bacteriological and physico-chemical evaluation of water coagulated with Moringa oleifera seed powder preparations on Challawa ... About 1.3 billion people still lack safe drinking water and more than 6 million children .... Temperature of the raw water samples was determined using a mercury – in – glass.

  11. Treating bulimia with hypnosis and low-level light therapy: a case report

    Science.gov (United States)

    Laser, Eleanor; Sassack, Michael

    2012-03-01

    This case report describes an effort to control bulimia nervosa by combining low-level laser therapy (LLLT)-the application of red and near-infrared light to specific body points-and hypnosis. A 29-year old female with a 14-year history of bulimia received one session of LLLT combined with hypnosis. Two weeks later, following a measurable decrease in bulimic episodes (purging), a session of psychotherapy and hypnosis was administered. Six months post-treatment, the patient has experienced a complete cessation of purging activities without recurrence. LLLT, when used in conjunction with hypnosis and psychotherapy, was effective in managing bulimia and may prove useful in treating other eating disorders.

  12. Multiregion, multigroup collision probability method with white boundary condition for light water reactor thermalization calculations

    International Nuclear Information System (INIS)

    Ozgener, B.; Ozgener, H.A.

    2005-01-01

    A multiregion, multigroup collision probability method with white boundary condition is developed for thermalization calculations of light water moderated reactors. Hydrogen scatterings are treated by Nelkin's kernel while scatterings from other nuclei are assumed to obey the free-gas scattering kernel. The isotropic return (white) boundary condition is applied directly by using the appropriate collision probabilities. Comparisons with alternate numerical methods show the validity of the present formulation. Comparisons with some experimental results indicate that the present formulation is capable of calculating disadvantage factors which are closer to the experimental results than alternative methods

  13. Comparative evaluation of recent water hammer events in light water reactors

    International Nuclear Information System (INIS)

    House, R.K.; Sursock, J.P.; Kim, J.H.

    1987-01-01

    Water hammer events that occurred in commercial U.S. light water reactors in the five-year period from 1981 to 1985 were surveyed, and a preliminary evaluation of the events was conducted. The information developed supplements a previous study which evaluated water hammer events in the twelve-year period from 1969 to 1981. The current study of water hammer events in the 1980's confirms that the rate of events remains relatively constant (less than 0.25 events per plant year) in both PWRs and BWRs. Although water hammer events are not normally considered a safety issue, the economic impact of the events on plant operations can be significant. One particular severe water hammer event is estimated to have cost the plant owner $10 million for repair and evaluation alone. A variety of key characteristics of the recent water hammer events are summarized to establish a basis for further study of preventative methods

  14. Fuel Summary Report: Shippingport Light Water Breeder Reactor - Rev. 2

    Energy Technology Data Exchange (ETDEWEB)

    Olson, Gail Lynn; Mc Cardell, Richard Keith; Illum, Douglas Brent

    2002-09-01

    The Shippingport Light Water Breeder Reactor (LWBR) was developed by Bettis Atomic Power Laboratory to demonstrate the potential of a water-cooled, thorium oxide fuel cycle breeder reactor. The LWBR core operated from 1977-82 without major incident. The fuel and fuel components suffered minimal damage during operation, and the reactor testing was deemed successful. Extensive destructive and nondestructive postirradiation examinations confirmed that the fuel was in good condition with minimal amounts of cladding deformities and fuel pellet cracks. Fuel was placed in wet storage upon arrival at the Expended Core Facility, then dried and sent to the Idaho Nuclear Technology and Engineering Center for underground dry storage. It is likely that the fuel remains in good condition at its current underground dry storage location at the Idaho Nuclear Technology and Engineering Center. Reports show no indication of damage to the core associated with shipping, loading, or storage.

  15. International students workshop on innovative light water reactors

    Energy Technology Data Exchange (ETDEWEB)

    Anglart, H. [Royal Inst. of Tech., Stockholm (Sweden). Nuclear Reactor Technology; Laurien, E. [Stuttgart Univ. (Germany). Inst. fuer Kernenergetik und Energiesysteme; Schulenberg, T. [Forschungszentrum Karlsruhe GmbH Technik und Umwelt (Germany). Inst. fuer Kern- und Energietechnik

    2008-06-15

    Nuclear reactor design is still one of the most fascinating subjects of mechanical engineering. Thirty students from 10 worldwide nations demonstrated this impressively in a recent workshop on supercritical water cooled reactors of the 4{sup th} generation, held from March 31 to April 3, 2008, in Karlsruhe, Germany, hosted by the Karlsruhe Institute of Technology. Bachelor and master students as well as young scientists working on their doctorate presented their own particular contribution to design and analyses of innovative reactor components, including its safety systems and other plant design. Their presentations were accompanied by lectures of leading scientists working in the European project of the 'High Performance Light Water Reactor' which is sponsored by the European Commission as part of its 6{sup th} Framework Programme. The workshop is an initiative of the Generation IV International Forum. (orig.)

  16. International students workshop on innovative light water reactors

    International Nuclear Information System (INIS)

    Anglart, H.; Laurien, E.; Schulenberg, T.

    2008-01-01

    Nuclear reactor design is still one of the most fascinating subjects of mechanical engineering. Thirty students from 10 worldwide nations demonstrated this impressively in a recent workshop on supercritical water cooled reactors of the 4 th generation, held from March 31 to April 3, 2008, in Karlsruhe, Germany, hosted by the Karlsruhe Institute of Technology. Bachelor and master students as well as young scientists working on their doctorate presented their own particular contribution to design and analyses of innovative reactor components, including its safety systems and other plant design. Their presentations were accompanied by lectures of leading scientists working in the European project of the 'High Performance Light Water Reactor' which is sponsored by the European Commission as part of its 6 th Framework Programme. The workshop is an initiative of the Generation IV International Forum. (orig.)

  17. Toward visible light response: Overall water splitting using heterogeneous photocatalysts

    KAUST Repository

    Takanabe, Kazuhiro

    2011-01-01

    Extensive energy conversion of solar energy can only be achieved by large-scale collection of solar flux. The technology that satisfies this requirement must be as simple as possible to reduce capital cost. Overall water splitting by powder-form photocatalysts directly produces a mixture of H 2 and O2 (chemical energy) in a single reactor, which does not require any complicated parabolic mirrors and electronic devices. Because of its simplicity and low capital cost, it has tremendous potential to become the major technology of solar energy conversion. Development of highly efficient photocatalysts is desired. This review addresses why visible light responsive photocatalysts are essential to be developed. The state of the art for the photocatalysts for overall water splitting is briefly described. Moreover, various fundamental aspects for developing efficient photocatalysts, such as particle size of photocatalysts, cocatalysts, and reaction kinetics are discussed. Copyright © 2011 De Gruyter.

  18. Effects of Corn Cob Treated with Sodium Chloride on Water ...

    African Journals Online (AJOL)

    The effects of four dietary treatments involving 50% cotton seed cake (CSC) and 50% corn cob treated with 0,5,10, and 15% were determined using a Completely Randomized Design in a 20-day trial. Treated corn cob and CSC (5%NaCl) increased the consumption of DM (317.88+54.65g/d) and CP (39.95±1.49g/d) ...

  19. ANALISIS PENGOLAHAN AIR TERPRODUKSI DI WATER TREATING PLANT PERUSAHAAN EKSPLOITASI MINYAK BUMI (STUDI KASUS: PT XYZ

    Directory of Open Access Journals (Sweden)

    Pertiwi Andaran

    2015-09-01

    Full Text Available The exploration and production process of oil and its supporting operations always generates waste as by-product. If they are uncontrolled, it might decrease the environmental quality. Thus, it is necessary to manage and treat the waste in order to meet the regulation standard of quality and quantity. PT XYZ is an energy company, particularly oil and gas production, which its production activity generate a large amount of waste as well as produced water. Thus, PT XYZ must have facilities or produced water handling plant which could minimize pollution caused by produced water. PT XYZ already has a system of produced water handling with recycling principle. After oil and water separation including water treating at Water Treating Plant (WTP, produced water will be used for steam injection. This is the part of enhanced oil recovery by steam flooding in Duri Field. Besides, produced water could be used as backwash water at WTP, that is Oil Removal Filter (ORF and Water Softener, which is called brine water. If the produced water and brine water is over load the capacity of oil enhanced recovery injection, it might be disposed through injection to Disposal Well and there are certain condition that produced water should be discharged into canal. The objective f this study is to analyze the performance of a water treating plant in PT XYZ. Water Treating Plant is a facility for treating produced water. Basically, WTP is on good condition and each unit has high efficiency for separating oil and water (60-99%. Horizontal velocity at pit #A of API Separator was larger than the design criteria. In addition, Water Softeners have efficiency until 99% for the hardness.

  20. Multi-Applications Small Light Water Reactor - NERI Final Report

    Energy Technology Data Exchange (ETDEWEB)

    S. Michale Modro; James E. Fisher; Kevan D. Weaver; Jose N. Reyes, Jr.; John T. Groome; Pierre Babka; Thomas M. Carlson

    2003-12-01

    The Multi-Application Small Light Water Reactor (MASLWR) project was conducted under the auspices of the Nuclear Energy Research Initiative (NERI) of the U.S. Department of Energy (DOE). The primary project objectives were to develop the conceptual design for a safe and economic small, natural circulation light water reactor, to address the economic and safety attributes of the concept, and to demonstrate the technical feasibility by testing in an integral test facility. This report presents the results of the project. After an initial exploratory and evolutionary process, as documented in the October 2000 report, the project focused on developing a modular reactor design that consists of a self-contained assembly with a reactor vessel, steam generators, and containment. These modular units would be manufactured at a single centralized facility, transported by rail, road, and/or ship, and installed as a series of self-contained units. This approach also allows for staged construction of an NPP and ''pull and replace'' refueling and maintenance during each five-year refueling cycle.

  1. Mechanical design of a light water breeder reactor

    Science.gov (United States)

    Fauth, Jr., William L.; Jones, Daniel S.; Kolsun, George J.; Erbes, John G.; Brennan, John J.; Weissburg, James A.; Sharbaugh, John E.

    1976-01-01

    In a light water reactor system using the thorium-232 -- uranium-233 fuel system in a seed-blanket modular core configuration having the modules arranged in a symmetrical array surrounded by a reflector blanket region, the seed regions are disposed for a longitudinal movement between the fixed or stationary blanket region which surrounds each seed region. Control of the reactor is obtained by moving the inner seed region thus changing the geometry of the reactor, and thereby changing the leakage of neutrons from the relatively small seed region into the blanket region. The mechanical design of the Light Water Breeder Reactor (LWBR) core includes means for axially positioning of movable fuel assemblies to achieve the neutron economy required of a breeder reactor, a structure necessary to adequately support the fuel modules without imposing penalties on the breeding capability, a structure necessary to support fuel rods in a closely packed array and a structure necessary to direct and control the flow of coolant to regions in the core in accordance with the heat transfer requirements.

  2. Qualification issues for advanced light-water reactor protection systems

    International Nuclear Information System (INIS)

    Korsah, K.; Clark, R.L.; Antonescu, C.

    1993-01-01

    The instrumentation and control (I ampersand C) systems in advanced reactors will make extensive use of digital controls, microprocessors, multiplexing, and fiber optic transmission. Elements of these advances in I ampersand C have been implemented on some current operating plants. However, the widespread use of the above technologies, as well as the use of artificial intelligence with minimum reliance on human operator control of reactors, highlights the need to develop standards for qualifying the I ampersand C used in the next generation of nuclear power plants. As a first step in this direction, the protection system I ampersand C for present-day plants was compared to that proposed for advanced light-water reactors (ALWRs). An evaluation template was developed by assembling a configuration of a safety channel instrument string for a generic ALWR, then comparing the impact of environmental stressors on that string to their effect on an equivalent instrument string from an existing light-water reactor. The template was then used to suggest a methodology for the qualification of microprocessor-based protection systems. The methodology identifies standards/regulatory guides (or lack thereof) for the qualification of microprocessor-based safety I ampersand C systems. This approach addresses in part issues raised in NRC policy document SECY-91-292, which recognizes that advanced I ampersand C systems for the nuclear industry are ''being developed without consensus standards. as the technology available for design is ahead of the technology that is well understood through experience and supported by application standards.''

  3. Ultraviolet light in the use of water disinfection

    International Nuclear Information System (INIS)

    Dabbagh, R.

    1999-01-01

    Ultraviolet light is an effective method in the use of water disinfection for swimming pools, potable water and industry required water. For many reasons UV light and UV compounded with chlorine (UV/chlorine) has been brought to attention in resent years. In this research, a swimming pool water disinfection was carried out by means of a system with the use of a reactor which was made of stainless steel (SS-304) and with many another standards required. Operation of system was carried out at first in the pilot plant and then installation in essential water treatment integrated. Inactivation of pollution index, E. Coli or Total coliform and Pseudomonas aeroginosa studied with 6000,16000 and 30000 μW.s/cm 2 UV dose and then in presence of 0.3,0.6,0.9 and 1.2 mg/1 free chlorine (UV/chlorine). In swimming pools minimum free chlorine residual usually is 1.5 mg/1. Optimum UV dose was 16000 μW.s/cm 2 attention to 50 percent UV absorption caused to TSS,TDS and turbidity. In the UV/chlorine system suitable rate was 16000μW.s/cm 2 UV dose /0.6 mg/1 chlorine in the 2.4 * 10 5 CFU/100 ml for Total coliform and 3600CFU/100 ml for Pseudomonas aeroginosa. Most probable number(MPN) estimated multiple tube fermentation technique. In this way the flow rate for system indicated about 240 cm 3 /s or 0.9 m 3 /h. The samples polluted for secondary pollution with 54000 CFU/100 ml for E.Coli and 1800 CFU/100ml Pseudomonas aeroginosa. The number of microbes decreased to zero duration after 45 minutes contact time in presence of free chlorine residual in samples. In practical conditions which that disinfectant system was installed in essential water treatment circuit under 1.4 atm hydraulic pressure no growth was seen for pollution index in disinfected water with UV in microbial density about 840 CFU/100 ml for Total coliform and 12CFU/100 ml for Pseudomonas aeroginosa. Attention to lower turbidity, TSS and TDS in tap water, higher flow rate about 560 cm 3 /s or 2 m 3 /h acessesed

  4. Histological changes in kidneys of adult rats treated with Monosodium glutamate: A light microscopic study

    Directory of Open Access Journals (Sweden)

    Singh BR, Ujwal Gajbe, Anil Kumar Reddy, Vandana Kumbhare

    2015-01-01

    Full Text Available Introduction: Monosodium Glutamate (MSG, which is chemically known as AJI-NO-MOTO also familiar as MSG in routine life. MSG is always considered to be a controversial food additive used in the world. It is a natural excitatory neurotransmitter, helps in transmitting the fast synaptic signals in one third of CNS. Liver and kidney play a crucial role in metabolism as well as elimination of MSG from the body. Present study is to detect structural changes in adult rat kidney tissue treated with MSG; observations are done with a light microscope. Materials & Methods: The study was conducted in the department of Anatomy, J.N.M.C, Sawangi (M Wardha. Thirty (30 adult Wistar rats (2-3 months old weighing about (200 ± 20g were used in the current study, animals were divided into three groups (Group – A, B, C. Group A: Control, Group B: 3 mg /gm body weight, Group C: 6 mg /gm body weight, MSG were administered orally daily for 45 days along with the regular diet. Observations & Results: The Mean values of animals weight at the end of experiment (46th day respectively were 251.2 ± 13, 244.4 ± 19.9 and 320 ± 31.1. Early degenerative changes like, Glomerular shrinkage (GSr, loss of brush border in proximal convoluted tubules and Cloudy degeneration was observed in sections of kidney treated with 3 mg/gm body weight of MSG. Animals treated with 6 mg/gm body weight of MSG showed rare changes like interstitial chronic inflammatory infiltrate with vacuolation in some of the glomeruli, and much glomerular shrinkage invaginated by fatty lobules. Conclusion: The effects of MSG on kidney tissues of adult rats revealed that the revelatory changes are directly proportional to the doses of MSG.

  5. Possible Use of Treated Wastewater as Irrigation Water at Urban Green Area

    Directory of Open Access Journals (Sweden)

    Elif Bozdoğan

    2014-08-01

    Full Text Available Ever increasing demands for fresh water resources have brought the reuse of treated wastewater into agendas. Wastewater has year-long potential to be used as an irrigation water source. Therefore, treated wastewater is used as irrigation water over agricultural lands and urban landscapes, as process water in industrial applications, as back-up water in environmental applications in water resources and wetlands of dry regions. The present study was conducted to investigate the possible use of domestic wastewater treated through pilot-scale constructed wetland of Adana-Karaisalı with dominant Mediterranean climate in irrigation of marigold (Tagetes erecta, commonly used over urban landscapes. Experiments were carried out between the dates May-November 2008 for 7 months with fresh water and treated wastewater. Plant growth parameters (plant height, plant diameter, number of branches and flowering parameters (number of flowers, flower diameter, flower pedicle thickness were monitored in monthly basis. Results revealed positive impacts of treated wastewater irrigations on plant growth during the initial 5 months between May-September but negative impacts in October and November. Similarly, treated wastewater irrigations had positive impacts on flowering parameters during the initial 3 months but had negative impacts during the subsequent 4 months. Such a case indicated shortened visual efficiencies of marigold. Therefore, treated wastewater can be used as an alternative water resource in irrigation of annual flowers, but better results can be attained by mixing treated wastewater with fresh water at certain ratios.

  6. One-year Surveillance of Human Enteric Viruses in Raw and Treated Wastewaters, Downstream River Waters, and Drinking Waters.

    Science.gov (United States)

    Iaconelli, M; Muscillo, M; Della Libera, S; Fratini, M; Meucci, L; De Ceglia, M; Giacosa, D; La Rosa, G

    2017-03-01

    Human enteric viruses are a major cause of waterborne diseases, and can be transmitted by contaminated water of all kinds, including drinking and recreational water. The objectives of the present study were to assess the occurrence of enteric viruses (enterovirus, norovirus, adenovirus, hepatitis A and E virus) in raw and treated wastewaters, in rivers receiving wastewater discharges, and in drinking waters. Wastewater treatment plants' (WWTP) pathogen removal efficiencies by adenovirus quantitative real-time PCR and the presence of infectious enterovirus, by cell culture assays, in treated wastewaters and in surface waters were also evaluated. A total of 90 water samples were collected: raw and treated wastewaters (treated effluents and ultrafiltered water reused for industrial purposes), water from two rivers receiving treated discharges, and drinking water. Nested PCR assays were used for the identification of viral DNA/RNA, followed by direct amplicon sequencing. All raw sewage samples (21/21), 61.9 % of treated wastewater samples (13/21), and 25 % of ultrafiltered water samples (3/12) were contaminated with at least one viral family. Multiple virus families and genera were frequently detected. Mean positive PCRs per sample decreased significantly from raw to treated sewage and to ultrafiltered waters. Moreover, quantitative adenovirus data showed a reduction in excess of 99 % in viral genome copies following wastewater treatment. In surface waters, 78.6 % (22/28) of samples tested positive for one or more viruses by molecular methods, but enterovirus-specific infectivity assays did not reveal infectious particles in these samples. All drinking water samples tested negative for all viruses, demonstrating the effectiveness of treatment in removing viral pathogens from drinking water. Integrated strategies to manage water from all sources are crucial to ensure water quality.

  7. Design of water rod cores of a direct cycle supercritical-pressure light water reactor

    International Nuclear Information System (INIS)

    Okano, Yasushi; Koshizuka, Sei-Ichi; Oka, Yoshiaki

    1994-01-01

    A conceptual design of a direct-cycle supercritical-pressure light water reactor with water rods is presented. Three types of water rods are analyzed: single, semi-double and full-double tubes. A water rod replaces seven fuel rods in a triangular lattice. The coolant density change in the water rods and the fuel channel is calculated using a code developed in the present study. The full double tube is most superior in terms of the distribution of the moderator. The number of fuel rods to water rods is 198:19, which makes optimum moderation. The average enrichment becomes 4.13%. The axial power flattening is finally achieved by partial length fuel rods and enrichment split of 0.25%. The discharge burnup is 45 GWd/t. (author)

  8. Status of advanced technology and design for water cooled reactors: Light water reactors

    International Nuclear Information System (INIS)

    1988-10-01

    Water reactors represent a high level of performance and safety. They are mature technology and they will undoubtedly continue to be the main stream of nuclear power. There are substantial technological development programmes in Member States for further improving the technology and for the development of new concepts in water reactors. Therefore the establishment of an international forum for the exchange of information and stimulation of international co-operation in this field has emerged. In 1987 the IAEA established the International Working Group on Advanced Technologies for Water-Cooled Reactors (IWGATWR). Within the framework of IWGATWR the IAEA Technical Report on Status of Advanced Technology and Design for Water Cooled Reactors, Part I: Light Water Reactors and Part II: Heavy Water Reactors has been undertaken to document the major current activities and different trends of technological improvements and developments for future water reactors. Part I of the report dealing with LWRs has now been prepared and is based mainly on submissions from Member States. It is hoped that this part of the report, containing the status of advanced light water reactor design and technology of the year 1987 and early 1988 will be useful for disseminating information to Agency Member States and for stimulating international cooperation in this subject area. 93 refs, figs and tabs

  9. Potential Of Water Hyacinth ( Eichhornia crassipes ) In Treating ...

    African Journals Online (AJOL)

    The potential use of water hyacinth (Eichhornia crassipes) as a means for water pollution abatement was investigated. Two types of industrial wastewaters, namely that from the textile/dyeing industry and raw sugar manufacturing were studied in batch systems. The percentage reduction in COD for textile effluents was on ...

  10. Assessment of microbiological quality of drinking water treated with ...

    African Journals Online (AJOL)

    The quality of drinking water at the point of delivery to the consumer is crucial in safeguarding consumer's health. The current study was undertaken to assess the changes in residual chlorine content with distance in water distribution system in Gwalior city of Madhya Pradesh and assess its relation with the occurrence of ...

  11. WET-tests on UV-treated ballast water

    NARCIS (Netherlands)

    Kaag, N.H.B.M.

    2015-01-01

    Damen Shipyards has developed a barge-based ballast water management system (BWMS) that enables direct treatment of ballast water during discharge in a receiving harbour. The treatment is based upon filtration and a once-through UV-treatment. As part of the Type Approval process, the Dutch

  12. [Diurnal variations in purifying-tanks when use Pontederia cordata treating the Malodorous River water].

    Science.gov (United States)

    Chen, Jian-jun; Lu, Xiao-ming; Lu, Shao-yong; Jin, Xiang-can; Huang, Min-sheng; Zhang, Yong; Zhao, Feng

    2009-12-01

    Aquatic plants (Ponsederie cordaza) were waked in two purifying-tanks to investigate the effects of illumination intensity and aeration on diurnal variations of Chla, SP, POD of Ponsederia cordaza and pH, DO, COD, NH4+ -N, TP of water from purifying-tanks when treating the malodorous river water at seven different times, another blank purifying-tank was set as a control. Comparative studies and correlation analysis of these different indicators were carried out to improve the plants working efficiency and provide scientific basis for optimal operation of plant purifying-tanks. Results showed that all indicators affected by changes of light, TP shows best correlation coefficient Cr = 0.93, p < 0.01) of physicochemical indicators and SP behaves best correlation coefficient Cr = 0.91 , p < 0.01) of plant physiology indicators in non-aeration purifying-tank;aeration is necessary as diurnal average of DO shows an increase of 0.13 mg/L by treatment of plant meanwhile 1.8 mg/L by plant with aeration,purifying-tanks with aeration got 7.1%, 6.3% higher removing rates of COD, NH4+ -N and 38% less TP removing rate than non-aeration plant purifying-tanks (p < 0.01); with aeration treatment, significant reduction of Chla, SP content (p < 0.05) and increase of POD activity (p < 0.05) observed in plants; the changes of illumination intensity and aeration can significantly affect physiological characteristics of plants and should be considered carefully and need further study when treating malodorous river water by plant purifying-tanks.

  13. Method of treating radioactive waste waters from uranium industry

    International Nuclear Information System (INIS)

    Priban, V.; Novak, L.; Zubcek, L.; Hinterholzinger, O.

    1987-01-01

    radioactive mine waters with suspended solid particles and acid salinated solutions from the process of underground leaching of radioactive ores with sulfuric acid, are discharged in a specified ratio to a common sump. The acid salinated solutions are used as a coagulation agent for the treatment of radioactive mine waters. Both solutions are mixed at simultaneous addition of lime milk suspension. In a sedimentation tank, the precipitate thus produced is sedimented and the clarified water is carried from the tank to a public water flow. The advantages of the method include the treatment of an over-balance 3 m 3 /min of acid salinated solutions from the process of underground leaching of radioactive ores with sulfuric acid, and reduction in the cost of radioactive mine water treatment. (E.S.)

  14. Fuel Summary Report: Shippingport Light Water Breeder Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Illum, D.B.; Olson, G.L.; McCardell, R.K.

    1999-01-01

    The Shippingport Light Water Breeder Reactor (LWBR) was a small water cooled, U-233/Th-232 cycle breeder reactor developed by the Pittsburgh Naval Reactors to improve utilization of the nation's nuclear fuel resources in light water reactors. The LWBR was operated at Shippingport Atomic Power Station (APS), which was a Department of Energy (DOE) (formerly Atomic Energy Commission)-owned reactor plant. Shippingport APS was the first large-scale, central-station nuclear power plant in the United States and the first plant of such size in the world operated solely to produce electric power. The Shippingport LWBR was operated successfully from 1977 to 1982 at the APS. During the five years of operation, the LWBR generated more than 29,000 effective full power hours (EFPH) of energy. After final shutdown, the 39 core modules of the LWBR were shipped to the Expended Core Facility (ECF) at Naval Reactors Facility at the Idaho National Engineering and Environmental Laboratory (INEEL). At ECF, 12 of the 39 modules were dismantled and about 1000 of more than 17,000 rods were removed from the modules of proof-of-breeding and fuel performance testing. Some of the removed rods were kept at ECF, some were sent to Argonne National Laboratory-West (ANL-W) in Idaho and some to ANL-East in Chicago for a variety of physical, chemical and radiological examinations. All rods and rod sections remaining after the experiments were shipped back to ECF, where modules and loose rods were repackaged in liners for dry storage. In a series of shipments, the liners were transported from ECF to Idaho Nuclear Technology Engineering Center (INTEC), formerly the Idaho Chemical Processing Plant (ICPP). The 47 liners containing the fully-rodded and partially-derodded core modules, the loose rods, and the rod scraps, are now stored in underground dry wells at CPP-749.

  15. Fuel Summary Report: Shippingport Light Water Breeder Reactor

    International Nuclear Information System (INIS)

    Illum, D.B.; Olson, G.L.; McCardell, R.K.

    1999-01-01

    The Shippingport Light Water Breeder Reactor (LWBR) was a small water cooled, U-233/Th-232 cycle breeder reactor developed by the Pittsburgh Naval Reactors to improve utilization of the nation's nuclear fuel resources in light water reactors. The LWBR was operated at Shippingport Atomic Power Station (APS), which was a Department of Energy (DOE) (formerly Atomic Energy Commission)-owned reactor plant. Shippingport APS was the first large-scale, central-station nuclear power plant in the United States and the first plant of such size in the world operated solely to produce electric power. The Shippingport LWBR was operated successfully from 1977 to 1982 at the APS. During the five years of operation, the LWBR generated more than 29,000 effective full power hours (EFPH) of energy. After final shutdown, the 39 core modules of the LWBR were shipped to the Expended Core Facility (ECF) at Naval Reactors Facility at the Idaho National Engineering and Environmental Laboratory (INEEL). At ECF, 12 of the 39 modules were dismantled and about 1000 of more than 17,000 rods were removed from the modules of proof-of-breeding and fuel performance testing. Some of the removed rods were kept at ECF, some were sent to Argonne National Laboratory-West (ANL-W) in Idaho and some to ANL-East in Chicago for a variety of physical, chemical and radiological examinations. All rods and rod sections remaining after the experiments were shipped back to ECF, where modules and loose rods were repackaged in liners for dry storage. In a series of shipments, the liners were transported from ECF to Idaho Nuclear Technology Engineering Center (INTEC), formerly the Idaho Chemical Processing Plant (ICPP). The 47 liners containing the fully-rodded and partially-derodded core modules, the loose rods, and the rod scraps, are now stored in underground dry wells at CPP-749

  16. The Consortium for Advanced Simulation of Light Water Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Ronaldo Szilard; Hongbin Zhang; Doug Kothe; Paul Turinsky

    2011-10-01

    The Consortium for Advanced Simulation of Light Water Reactors (CASL) is a DOE Energy Innovation Hub for modeling and simulation of nuclear reactors. It brings together an exceptionally capable team from national labs, industry and academia that will apply existing modeling and simulation capabilities and develop advanced capabilities to create a usable environment for predictive simulation of light water reactors (LWRs). This environment, designated as the Virtual Environment for Reactor Applications (VERA), will incorporate science-based models, state-of-the-art numerical methods, modern computational science and engineering practices, and uncertainty quantification (UQ) and validation against data from operating pressurized water reactors (PWRs). It will couple state-of-the-art fuel performance, neutronics, thermal-hydraulics (T-H), and structural models with existing tools for systems and safety analysis and will be designed for implementation on both today's leadership-class computers and the advanced architecture platforms now under development by the DOE. CASL focuses on a set of challenge problems such as CRUD induced power shift and localized corrosion, grid-to-rod fretting fuel failures, pellet clad interaction, fuel assembly distortion, etc. that encompass the key phenomena limiting the performance of PWRs. It is expected that much of the capability developed will be applicable to other types of reactors. CASL's mission is to develop and apply modeling and simulation capabilities to address three critical areas of performance for nuclear power plants: (1) reduce capital and operating costs per unit energy by enabling power uprates and plant lifetime extension, (2) reduce nuclear waste volume generated by enabling higher fuel burnup, and (3) enhance nuclear safety by enabling high-fidelity predictive capability for component performance.

  17. Light requirements of water lobelia (Lobelia dortmanna L.

    Directory of Open Access Journals (Sweden)

    Borowiak Dariusz

    2017-12-01

    Full Text Available Maximum depth of colonization (zC and total area covered by a population of Lobelia dortmanna, as well as underwater light regime were studied in 25 soft water lobelia lakes in north-western Poland. Variations in underwater light conditions among the lakes were described by Secchi disc depths (zSD, and by attenuation coefficients of irradiance within photosynthetically active radiation range (Kd,PAR, and euphotic zone depths (zEU derived from photometric measurements conducted twice a year (in midspring and midsummer during the period 2014–2015. Maximum depth of colonization of water lobelia ranged from 0.1 to 2.2 m (median zC = 0.8 m; mean zC = 1.0 m. Nine lakes showed the relative coverage of the littoral zone (RCLZ by L. dortmanna to be greater than the mean value, which was 4.8%. Studies showed that light requirements of water lobelia increase when the maximum depth of colonization also increases. This pattern could be partially related to the greater energy needs of deeper growing individuals due to enlarged seed production and their incubation, and for the creation of much heavier inflorescences. Assessment of the light requirements of L. dortmanna along the depth gradient indicates that relative irradiance (percentage of subsurface irradiance of PAR should be at the level of: (i 47–50% (annual total of quantum irradiance 3083–3280 mol m−2 yr−2 for plants growing within a depth range of 2.0–2.5 m; (ii 44–47% (2886–3083 mol m−2yr−1 for plants growing within a depth range of 1.5–2.0 m; (iii 41–44% (2690–2886 mol m−2yr−2 for plants growing within a depth range of 1.0–1.5 m; and (iv 34–41% (2230–2690 mol m−1 yr−1 for those growing in the littoral zone at a depth of between 0.5 and 1.0 m. In average conditions in the Pomeranian lakes, the maximum depth of colonization by L. dortmanna accounts for approximately a third of the Secchi disc depth and a fifth of the depth of the euphotic zone with irradiance

  18. Influence of untreated and bacterial-treated Yamuna water on the ...

    African Journals Online (AJOL)

    In present study an attempt has been made to study the pollution level of river Yamuna at Agra, by analyzing the physico-chemical parameters of untreated and bacterial-treated water and its effect on the growth of maize plant. Among different concentrations (25, 50, 75 and 100%) of treated water, the 100% concentration of ...

  19. High-level radioactive waste from light-water reactors

    International Nuclear Information System (INIS)

    Cohen, B.L.

    1977-01-01

    The production of radioactive nuclei during the operation of a light-water reactor is traced, and their decay history is followed. The potential environmental impacts of this waste are calculated and shown to be comparable to those of other materials we produce. Assuming deep burial, it is shown that there are important time delays which prevent the waste from reaching the biosphere in the first few hundred years while its toxicity is decreasing by several orders of magnitude. In the long term,,the most important pathway to man was found to be through groundwater into food and water supplies, with consequences calculated t to be 0.4 fatalities in 10 6 years from each year of all-nuclear power in U.S. Other pathways considered and found to be less important include meteorites, volcanism, release through ground water to airborne particulate, and human intrusion by drilling and mining for unspecified materials and for salt. For time scales longer than 10 6 years, nuclear power is shown to reduce man's exposure to radiation by consuming uranium. A cost-benefit analysis is developed for surveillance of buried waste. It is shown that buried high-level waste is environmentally much less dangerous than uranium mill tailings

  20. Multiangular hyperspectral investigation of polarized light in case 2 waters

    Science.gov (United States)

    Tonizzo, A.; Zhou, J.; Gilerson, A.; Chowdhary, J.; Gross, B.; Moshary, F.; Ahmed, S.

    2009-09-01

    The focus of this work is on the dependence of in situ hyperspectral and multiangular polarized data on the size distribution and refractive index of the suspended particles. Underwater polarization measurements were obtained using a polarimeter developed at the Optical Remote Sensing Laboratory of the City College of New York, NY. The degree of polarization (DOP) of the underwater light field in coastal environments was measured and the water-leaving polarized radiance was derived. In-water optical properties were also measured with an ac-9 (WET Labs). Absorption and attenuation spectra are then used to derive information on the dissolved and suspend components in the water medium which are used in a vector radiative transfer code which provides the upwelling radiance. The model was run for various values of the refractive index of mineral particles until the modeled DOP matched the measured one. The relationship between the intensity of the maximum of the DOP and both the refractive index of the mineral particles and the shapes of their size distributions is analyzed in detail.

  1. Creosote movement from treated wood immersed in fresh water

    Science.gov (United States)

    Sung-Mo Kang; Jeffrey J. Morrell; John Simonsen; Stan Lebow

    2005-01-01

    Creosote has a long history of successful use as a wood preservative, but polycyclic aromatic hydrocarbons in this preservative have raised environmental concerns, particularly when creosote-treated wood is used in aquatic environments. A number of models have been developed to predict the risk of creosote use in aquatic environments, but one limitation of these models...

  2. Status of advanced light water reactor designs 2004

    International Nuclear Information System (INIS)

    2004-05-01

    The report is intended to be a source of reference information for interested organizations and individuals. Among them are decision makers of countries considering implementation of nuclear power programmes. Further, the report is addressed to government officials with an appropriate technical background and to research institutes of countries with existing nuclear programmes that wish to be informed on the global status in order to plan their nuclear power programmes including both research and development efforts and means for meeting future. The future utilization of nuclear power worldwide depends primarily on the ability of the nuclear community to further improve the economic competitiveness of nuclear power plants while meeting stringent safety requirements. The IAEA's activities in nuclear power technology development include the preparation of status reports on advanced reactor designs to provide all interested IAEA Member States with balanced and objective information on advances in nuclear plant technology. In the field of light water reactors, the last status report published by the IAEA was 'Status of Advanced Light Water Cooled Reactor Designs: 1996' (IAEA-TECDOC-968). Since its publication, quite a lot has happened: some designs have been taken into commercial operation, others have achieved significant steps toward becoming commercial products, including certification from regulatory authorities, some are in a design optimization phase to reduce capital costs, development for other designs began after 1996, and a few designs are no longer pursued by their promoters. With this general progress in mind, on the advice and with the support of the IAEA Department of Nuclear Energy's Technical Working Group on Advanced Technologies for Light Water Reactors (LWRs), the IAEA has prepared this new status report on advanced LWR designs that updates IAEA-TECDOC-968, presenting the various advanced LWR designs in a balanced way according to a common outline

  3. Japanese simplified light water reactors using passive safety systems

    International Nuclear Information System (INIS)

    Oka, Y.; Naitoh, M.; Kiyose, R.

    1991-01-01

    Concepts fo small and medium-sized light water reactors for the next generation have been developed by Japanese nuclear plant vendors. These are called HSBWR and MSPWR. The basic design philosophy was (1) to improve economy to avoid scale demerits mainly by decreasing the capital costs of construction and (2) to improve safety margin by incorporating passive safety systems. Both HSBWR and MSPWR utilize active components as part of safety systems, but their role is greatly limited, whereas passive components are widely incorporated. The grace period of HSBWR is one day of infinite as an option for emergency core cooling, and three days for residual heat removal. As for MSPWR, it is three days for both events. For both HSBWR and MSPWR, improvement of economy is largely contributed by short construction period less than three years, continuous operation period of two years, and periodical inspection time required less than 40 days. (author)

  4. Power generation versus fuel production in light water hybrid reactors

    International Nuclear Information System (INIS)

    Greenspan, E.

    1977-06-01

    The economic potentials of fissile-fuel-producing light-water hybrid reactors (FFP-LWHR) and of fuel-self-sufficient (FSS) LWHR's are compared. A simple economic model is constructed that gives the capital investment allowed for the hybrid reactor so that the cost of electricity generated in the hybrid based energy system equals the cost of electricity generated in LWR's. The power systems considered are LWR, FSS-LWHR, and FFP-LWHR plus LWR, both with and without plutonium recycling. The economic potential of FFP-LWHR's is found superior to that of FSS-LWHR's. Moreover, LWHR's may compete, economically, with LWR's. Criteria for determining the more economical approach to hybrid fuel or power production are derived for blankets having a linear dependence between F and M. The examples considered favor the power generation rather than fuel production

  5. Standard Guide for Benchmark Testing of Light Water Reactor Calculations

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2010-01-01

    1.1 This guide covers general approaches for benchmarking neutron transport calculations in light water reactor systems. A companion guide (Guide E2005) covers use of benchmark fields for testing neutron transport calculations and cross sections in well controlled environments. This guide covers experimental benchmarking of neutron fluence calculations (or calculations of other exposure parameters such as dpa) in more complex geometries relevant to reactor surveillance. Particular sections of the guide discuss: the use of well-characterized benchmark neutron fields to provide an indication of the accuracy of the calculational methods and nuclear data when applied to typical cases; and the use of plant specific measurements to indicate bias in individual plant calculations. Use of these two benchmark techniques will serve to limit plant-specific calculational uncertainty, and, when combined with analytical uncertainty estimates for the calculations, will provide uncertainty estimates for reactor fluences with ...

  6. Non-linear analysis in Light Water Reactor design

    International Nuclear Information System (INIS)

    Rashid, Y.R.; Sharabi, M.N.; Nickell, R.E.; Esztergar, E.P.; Jones, J.W.

    1980-03-01

    The results obtained from a scoping study sponsored by the US Department of Energy (DOE) under the Light Water Reactor (LWR) Safety Technology Program at Sandia National Laboratories are presented. Basically, this project calls for the examination of the hypothesis that the use of nonlinear analysis methods in the design of LWR systems and components of interest include such items as: the reactor vessel, vessel internals, nozzles and penetrations, component support structures, and containment structures. Piping systems are excluded because they are being addressed by a separate study. Essentially, the findings were that nonlinear analysis methods are beneficial to LWR design from a technical point of view. However, the costs needed to implement these methods are the roadblock to readily adopting them. In this sense, a cost-benefit type of analysis must be made on the various topics identified by these studies and priorities must be established. This document is the complete report by ANATECH International Corporation

  7. Non-linear analysis in Light Water Reactor design

    Energy Technology Data Exchange (ETDEWEB)

    Rashid, Y.R.; Sharabi, M.N.; Nickell, R.E.; Esztergar, E.P.; Jones, J.W.

    1980-03-01

    The results obtained from a scoping study sponsored by the US Department of Energy (DOE) under the Light Water Reactor (LWR) Safety Technology Program at Sandia National Laboratories are presented. Basically, this project calls for the examination of the hypothesis that the use of nonlinear analysis methods in the design of LWR systems and components of interest include such items as: the reactor vessel, vessel internals, nozzles and penetrations, component support structures, and containment structures. Piping systems are excluded because they are being addressed by a separate study. Essentially, the findings were that nonlinear analysis methods are beneficial to LWR design from a technical point of view. However, the costs needed to implement these methods are the roadblock to readily adopting them. In this sense, a cost-benefit type of analysis must be made on the various topics identified by these studies and priorities must be established. This document is the complete report by ANATECH International Corporation.

  8. Commercial Light Water Reactor Tritium Extraction Facility Geotechnical Summary Report

    Energy Technology Data Exchange (ETDEWEB)

    Lewis, M R

    2000-01-11

    A geotechnical investigation program has been completed for the Circulating Light Water Reactor - Tritium Extraction Facility (CLWR-TEF) at the Savannah River Site (SRS). The program consisted of reviewing previous geotechnical and geologic data and reports, performing subsurface field exploration, field and laboratory testing and geologic and engineering analyses. The purpose of this investigation was to characterize the subsurface conditions for the CLWR-TEF in terms of subsurface stratigraphy and engineering properties for design and to perform selected engineering analyses. The objectives of the evaluation were to establish site-specific geologic conditions, obtain representative engineering properties of the subsurface and potential fill materials, evaluate the lateral and vertical extent of any soft zones encountered, and perform engineering analyses for slope stability, bearing capacity and settlement, and liquefaction potential. In addition, provide general recommendations for construction and earthwork.

  9. Safety considerations concerning light water reactors in Sweden

    International Nuclear Information System (INIS)

    Nilsson, T.

    1977-01-01

    In 1975 the Swedish Nuclear Power Inspectorate was commissioned by the Government to perform a Reactor Safety Study concerning commercial light water reactors. The study will contain an account of: - rules and regulations for reactor designs; - operation experience of the Swedish nuclear power plants with international comparisons; - the development of reactor designs during the last 10 years; - demands and conditions for inspection and inspection methods; - nuclear power plant operation organization; - training of operators; and - the results of research into nuclear safety. The study is scheduled for completion by July 1st, 1977, however, this paper gives a summary of the results of the Reactor Safety Study already available. The paper contains detailed statistics concerning safety related occurrences and reactor scrams in Sweden from July 1st, 1974 until the beginning of 1977

  10. The United States Advanced Light Water reactor (USALWR) development program

    International Nuclear Information System (INIS)

    Stahlkopf, K.E.; Noble, D.M.; Devine, Jr.J.C.; Sugnet, W.R.

    1987-01-01

    For the United States Nuclear power industry to remain viable, it must be prepared to meet the expected need for a new generation capacity in the late 90s with an improved reactor system. The best hope of meeting this requirement is with revolutionary changes to current LWR systems through simplification and re-evaluation of safety and operational design margins. In addition, the grid characteristics and the difficulty in raising capital for large projects indicate the smaller light water reactors (600 MWe) may play an important role in the next generation. A cooperative and coordinated program between EPRI, U.S. DOE, the major architect engineers, nuclear steam supply vendors, and the NRC in the U.S. has been undertaken with four major goals in mind. (author)

  11. Isotopic correlations in fission gases applied to light water reactors

    International Nuclear Information System (INIS)

    Rousset, Pierre.

    1978-01-01

    The study of stable fission gases, released from irradiated fuel elements, allows not only the kinetics of release to be determined as a function of the irradiation conditions, but also very useful experimental correlations to be laid down in view of specifying irradiation parameters: specific burn-up and linear power. The LECI (Laboratoire d'Etude des Combustibles Irradies) at Saclay has effected for many years qualitative and quantitative analysis of the stable fission gases released from enriched UO 2 based fuels in the framework of quality control of the fuels for light water reactors (especially PWR). The use of the numerous results obtained in various conditions allowed a detail study of the isotope ratio for Xe and Kr, which may be applied to test elements and power assemblies [fr

  12. Nuclide inventories of spent fuels from light water reactors

    International Nuclear Information System (INIS)

    Okumura, Keisuke; Okamoto, Tsutomu

    2012-02-01

    Accurate information on nuclide inventories of spent fuels from Light Water Reactors (LWRs) is important for evaluations of criticality, decay heat, radioactivity, toxicity, and so on, in the safety assessments of storage, transportation, reprocessing and waste disposal of the spent fuels. So, a lot of lattice burn-up calculations were carried out for the possible fuel specifications and irradiation conditions in Japanese commercial LWRs by using the latest nuclear data library JENDL-4.0 and a sophisticated lattice burn-up calculation code MOSRA-SRAC. As a result, burn-up changes of nuclide inventories and their possible ranges were clarified for 21 heavy nuclides and 118 fission products, which are important from the viewpoint of impacts to nuclear characteristics and nuclear fuel cycle and environment. (author)

  13. The United States advanced light water reactor (USALWR) development program

    International Nuclear Information System (INIS)

    Stahlkopf, K.E.; Noble, D.M.; Devine, J.C. Jr.; Sugnet, W.R.

    1987-01-01

    For the United States Nuclear Power industry to remain viable, it must be prepared to meet the expected need for a new generation capacity in the late 90s with an improved reactor system. The best hope of meeting this requirement is with revolutionary changes to current LWR systems through simplification and re-evaluation of safety and operational design margins. In addition, the grid characteristics and the difficulty in raising capital for large projects indicate the smaller light water reactors (600 MWe) may play an important role in the next generation. A cooperative and coordinated program between EPRI, U.S. DOE, the major architect engineers, nuclear steam supply vendors, and the NRC in the U.S. has been undertaken with four major goals in mind

  14. Conceptual design study of high conversion light water reactor

    International Nuclear Information System (INIS)

    Okumura, Keisuke; Akie, Hiroshi; Mori, Takamasa; Nakagawa, Masayuki; Ishiguro, Yukio

    1990-06-01

    Since 1984, R and D work has been made for high conversion light water reactors (HCLWRs), at JAERI, to improve the natural uranium saving and effective plutonium utilization by the use of conventional or extended LWR technology. This report summarizes the results of the feasibility study made mainly from the viewpoint of nuclear design in the Phase-I Program (1985∼1989). Until now, the following various types of HCLWR core concepts have been investigated; 1) homogeneous core with tight pitch lattice of fuel rods, 2) homogeneous core with semi-tight pitch lattice, 3) spectral shift core using fertile rod with semi-tight pitch lattice, 4) flat-core, 5) axial heterogeneous core. The core burnup and thermohydraulic analyses during normal operations have been performed to clear up the burnup performances and feasibility for each core. Based on the analysis results, the axial heterogeneous HCLWR core was selected as the JAERI reference core. (author)

  15. Materials Inventory Database for the Light Water Reactor Sustainability Program

    Energy Technology Data Exchange (ETDEWEB)

    Kazi Ahmed; Shannon M. Bragg-Sitton

    2013-08-01

    Scientific research involves the purchasing, processing, characterization, and fabrication of many sample materials. The history of such materials can become complicated over their lifetime – materials might be cut into pieces or moved to various storage locations, for example. A database with built-in functions to track these kinds of processes facilitates well-organized research. The Material Inventory Database Accounting System (MIDAS) is an easy-to-use tracking and reference system for such items. The Light Water Reactor Sustainability Program (LWRS), which seeks to advance the long-term reliability and productivity of existing nuclear reactors in the United States through multiple research pathways, proposed MIDAS as an efficient way to organize and track all items used in its research. The database software ensures traceability of all items used in research using built-in functions which can emulate actions on tracked items – fabrication, processing, splitting, and more – by performing operations on the data. MIDAS can recover and display the complete history of any item as a simple report. To ensure the database functions suitably for the organization of research, it was developed alongside a specific experiment to test accident tolerant nuclear fuel cladding under the LWRS Advanced Light Water Reactor Nuclear Fuels Pathway. MIDAS kept track of materials used in this experiment from receipt at the laboratory through all processes, test conduct and, ultimately, post-test analysis. By the end of this process, the database proved to be right tool for this program. The database software will help LWRS more efficiently conduct research experiments, from simple characterization tests to in-reactor experiments. Furthermore, MIDAS is a universal tool that any other research team could use to organize their material inventory.

  16. Hole injection enhancement in organic light emitting devices using plasma treated graphene oxide

    Energy Technology Data Exchange (ETDEWEB)

    Jesuraj, P. Justin; Parameshwari, R. [Centre for Nanoscience and Nanotechnology, School of Physics, Bharathidasan University, Tiruchirappalli, 620 024, Tamil Nadu (India); Kanthasamy, K.; Koch, J. [Institut für Festkörperphysik, ATMOS, Appelstr. 2, D-30167, Hannover (Germany); Pfnür, H. [Institut für Festkörperphysik, ATMOS, Appelstr. 2, D-30167, Hannover (Germany); Laboratorium für Nano- und Quantene$ngineering, Schneiderberg 30, D-30167, Hannover (Germany); Jeganathan, K., E-mail: kjeganathan@yahoo.com [Centre for Nanoscience and Nanotechnology, School of Physics, Bharathidasan University, Tiruchirappalli, 620 024, Tamil Nadu (India)

    2017-03-01

    Graphical abstract: Plasma treated Graphene oxide for hole injection enhancement in OLEDs. - Highlights: • Oxygen (O{sub 2}) and hydrogen (H{sub 2}) plasma exposed graphene oxide (GO) sheets have been demonstrated as hole buffer layers in OLEDs. • O{sub 2} plasma exposure induces assimilation of oxygen contents in GO lattice resulting in improved work function that reduced the hole injection barrier further. Whereas, H{sub 2} plasma contrastingly reduced the GO by excluding oxygen which ensuing lower work function. • X-ray photoelectron spectroscopy and ultraviolet photoelectron spectroscopy investigations reveal the capricious amount of oxygen in GO lattice and its corresponding work function variations. • GO and O{sub 2} plasma treated GO significantly improves the current efficiency of OLEDs more than one order with notable reduction in turn on voltage. - Abstract: The hole injection layer (HIL) with high work function (WF) is desirable to reduce the injection barrier between anode and hole transport layer in organic light emitting devices (OLED). Here, we report a novel approach to tune the WF of graphene oxide (GO) using oxygen and hydrogen plasma treatment and its hole injection properties in OLEDs. The mild exposure of oxygen plasma on GO (O{sub 2}-GO) significantly reduces the injection barrier by increasing the WF of anode (4.98 eV) through expansion of C−O bonds. In contrast, the hole injection barrier was drastically increased for hydrogen plasma treated GO (H{sub 2}-GO) layers as the WF is lowered by the contraction of C−O bond. By employing active O{sub 2}-GO as HIL in OLEDs found to exhibit superior current efficiency of 4.2 cd/A as compared to 3.3 cd/A for pristine GO. Further, the high injection efficiency of O{sub 2}-GO infused hole only device can be attributed to the improved energy level matching. Ultraviolet and X-ray photoelectron spectroscopy were used to correlate the WF of HIL infused anode towards the enhanced performance of

  17. Assessment of microbiological quality of drinking water treated with ...

    African Journals Online (AJOL)

    user

    mainly covers detection of coliforms and total bacterial count. Coliforms are common bacteria that exist in the intestines of human beings and mammals, and excreted out in the dejection. If large quantities of coliforms are present in the water, it is a prominent indicator of possible contamination caused by dejection of human ...

  18. Effects of magnetically treated water on germination and growth of ...

    African Journals Online (AJOL)

    Lycopersicon Esculentum: variety UC82B) plant. The water was allowed to pass through magnetic treatment pipe for duration of 113 s. The mean magnetic flux density used was 719 gauss (G) measured inside the pipe. The treatments (T1 to T5) were ...

  19. Water cooled metal optics for the Advanced Light Source

    International Nuclear Information System (INIS)

    McKinney, W.R.; Irick, S.C.; Lunt, D.L.J.

    1991-01-01

    The program for providing water cooled metal optics for the Advanced Light Source at Berkeley is reviewed with respect to fabrication and metrology of the surfaces. Materials choices, surface figure and smoothness specifications, and metrology systems for measuring the plated metal surfaces are discussed. Results from prototype mirrors and grating blanks will be presented, which show exceptionally low microroughness and mid-period error. We will briefly describe out improved version of the Long Trace Profiler, and its importance to out metrology program. We have completely redesigned the mechanical, optical and computational parts of the profiler system with the cooperation of Peter Takacs of Brookhaven, Continental Optical, and Baker Manufacturing. Most important is that one of our profilers is in use at the vendor to allow testing during fabrication. Metrology from the first water cooled mirror for an ALS beamline is presented as an example. The preplating processing and grinding and polishing were done by Tucson Optical. We will show significantly better surface microroughness on electroless nickel, over large areas, than has been reported previously

  20. A new book : 'light-water reactor materials'

    International Nuclear Information System (INIS)

    Olander, Donald R.; Motta, Arthur T.

    2005-01-01

    The contents of a new book currently in preparation are described. The dearth of books in the field of nuclear materials has left both students in nuclear materials classes and professionals in the same field without a resource for the broad fundamentals of this important sub-discipline of nuclear engineering. The new book is devoted entirely to materials problems in the core of light-water reactors, from the pressure vessel into the fuel. Key topics deal with the UO 2 fuel, zircaloy cladding, stainless steel, and of course, water. The restriction to LWR materials does not mean a short monograph; the enormous quantity of experimental and theoretical work over the past 50 years on these materials presents a challenge of culling the most important features and explaining them in the simplest quantitative fashion. Moreover, LWRs will probably be the sole instrument of the return of nuclear energy in electric power production for the next decade or so. By that time, a new book will be needed

  1. Tritium separation from light and heavy water by bipolar electrolysis

    International Nuclear Information System (INIS)

    Ramey, D.W.; Petek, M.; Taylor, R.D.; Kobisk, E.H.; Ramey, J.; Sampson, C.A.

    1979-10-01

    Use of bipolar electrolysis with countercurrent electrolyte flow to separate hydrogen isotopes was investigated for the removal of tritium from light water effluents or from heavy water moderator. Deuterium-tritium and protium-tritium separation factors occurring on a Pd-25% Ag bipolar electrode were measured to be 2.05 to 2.16 and 11.6 to 12.4 respectively, at current densities between 0.21 and 0.50 A cm -2 , and at 35 to 90 0 C. Current densities up to 0.3 A cm -2 have been achieved in continuous operation, at 80 to 90 0 C, without significant gas formation on the bipolar electrodes. From the measured overvoltage at the bipolar electrodes and the electrolyte conductivity the power consumption per stage was calculated to be 3.0 kwh/kg H 2 O at 0.2 A cm -2 and 5.0 kwh/kg H 2 O at 0.5 A cm -2 current density, compared to 6.4 and 8.0 kwh/kg H 2 O for normal electrolysis. A mathematical model derived for hydrogen isotope separation by bipolar electrolysis, i.e., for a square cascade, accurately describes the results for protium-tritium separation in two laboratory scale, multistage experiments with countercurrent electrolyte flow; the measured tiritum concentration gradient through the cascade agreed with the calculated values

  2. Water cooled metal optics for the Advanced Light Source

    International Nuclear Information System (INIS)

    McKinney, W.R.; Irick, S.C.; Lunt, D.L.J.

    1992-01-01

    The program for providing water cooled metal optics for the Advanced Light Source at Berkeley is reviewed with respect to fabrication and metrology of the surfaces. Materials choices, surface figure and smoothness specifications, and metrology systems for measuring the plated metal surfaces are discussed. Results from prototype mirrors and grating blanks will be presented, which show exceptionally low microroughness and midperiod error. We will briefly describe our improved version of the long trace profiler, and its importance to our metrology program. We have completely redesigned the mechanical, optical and computational parts of the profiler system with the cooperation of P. Takacs of Brookhaven, Continental Optical, and Baker Manufacturing. Most important is that one of our profilers is in use at the vendor to allow testing during fabrication. Metrology from the first water cooled mirror for an ALS beamline is presented as an example. This 15 in. long Glidcop T M mirror is coated with electroless nickel from Acteron Corporation in Redwood City, CA. The preplating processing and grinding and polishing were done by Tucson Optical. We will show significantly better surface microroughness on electroless nickel, over large areas, than has been reported previously. (orig.)

  3. Plasma Treated Active Carbon for Capacitive Deionization of Saline Water

    Directory of Open Access Journals (Sweden)

    Aiping Zeng

    2017-01-01

    Full Text Available The plasma treatment on commercial active carbon (AC was carried out in a capacitively coupled plasma system using Ar + 10% O2 at pressure of 4.0 Torr. The RF plasma power ranged from 50 W to 100 W and the processing time was 10 min. The carbon film electrode was fabricated by electrophoretic deposition. Micro-Raman spectroscopy revealed the highly increased disorder of sp2 C lattice for the AC treated at 75 W. An electrosorption capacity of 6.15 mg/g was recorded for the carbon treated at 75 W in a 0.1 mM NaCl solution when 1.5 V was applied for 5 hours, while the capacity of the untreated AC was 1.01 mg/g. The plasma treatment led to 5.09 times increase in the absorption capacity. The jump of electrosorption capacity by plasma treatment was consistent with the Raman spectra and electrochemical double layer capacitance. This work demonstrated that plasma treatment was a potentially efficient approach to activating biochar to serve as electrode material for capacitive deionization (CDI.

  4. Water chemistry control to meet the advanced design and operation of light water reactors

    International Nuclear Information System (INIS)

    Shirai, Hiroshi; Uchida, Shunsuke; Naitoh, Masanori; Okada, Hidetoshi; Sato, Masatoshi

    2014-01-01

    Water chemistry control is one of the key technologies to establish safe and reliable operation of nuclear power plants. The road maps on R and D plans for water chemistry of nuclear power systems in Japan have been proposed along with promotion of R and D related water chemistry improvement for the advanced application of light water reactors (LWRs). The technical trends were divided into four categories, dose rate reduction, structural integrity, fuel integrity and radioactive waste reduction, and latest technical break through for each category was shown for the advanced application of LWRs. At the same time, the technical break through and the latest movements for regulation of water chemistry were introduced for each of major organizations related to nuclear engineering in the world. The conclusions were summarized as follows; 1. Water chemistry improvements might contribute to achieve the advanced application of LWRs, while water chemistry should be often changed to achieve the advanced application of LWRs. 2. Only one solution for water chemistry control was not obtained for achieving the advanced application of LWRs, but miscellaneous solutions were possible for achieving one. Optimal water chemistry control was desired for having the good practices for satisfying multi-targets at the same time and it was much affected by the plant unique systems and operational history. 3. That meant it was difficult to determine water chemistry regulation targets for achieving application of LWRs but it was necessary to prepare suitable guideline for good achievement of application of LWRs. That meant the guideline should be recommendation for good practice in the plant. 4. The water chemistry guide line should be modified along with progress of plant operation and water chemistry and related technologies. (author)

  5. 77 FR 55877 - Initial Test Program of Condensate and Feedwater Systems for Light-Water Reactors

    Science.gov (United States)

    2012-09-11

    ... Systems for Light-Water Reactors AGENCY: Nuclear Regulatory Commission. ACTION: Regulatory guide; issuance... Systems for Boiling Water Reactor Power Plants.'' This regulatory guide is being revised to: (1) Expand... for the condensate and feedwater systems in all types of light water reactor facilities; and (2) to...

  6. Comparison of Novel Carboneous Structures to Treat Nitroaromatic Impacted Water

    Science.gov (United States)

    2015-12-01

    34 Fluidized - bed system : activated activated of a using anaerobic reactors reactors granular and aerobic carbon sludge." Water Environment Research 67(7...3 Figure 2. SEM images of the grinded GAC granules ...................................................... 30 Figure 3. SEM images of...their pristine states after receipt. However, GAC was pulverized with a mortar and pestle in order to increase homogeneity of the granules , and reduce

  7. Effects of treated waste water irrigation on some qualitative charcterstics of forage sorghum, corn and millet

    Directory of Open Access Journals (Sweden)

    alireza emami

    2009-06-01

    Full Text Available In order to study the effects of irrigation with different levels of urban treated waste water on feeding value of forage sorghum (Var. Speed feed and Sugar graze, maize (Var. SC 704 and millet (Var. Nutrifeed an experiment was conducted at Experimental Station No.1, Astan Qods Razavi Mashhad, and Animal Nutrition Laboratory, College of Agriculture, Ferdowsi University of Mashhad. Four varieties of forage plants with five levels of treated waste water: %0, %25, %50, %75 and %100 were compared in a split-plot experiment based on Randomized Complete Block Design with four replications per treatment. Feeding values of forage plants such as Crude Protein content (CP, Neutral Detergent Fiber content (NDF, in vitro Dry Matter Digestibility (DMD, Organic Matter Digestibility (OMD and D-Value were measured. Results showed that treated waste water irrigation had a significant effect on crude protein content. The highest crude protein content was shown at % 100 treated waste water ( %13.76 and the lowest was shown at % treated waste water (%9.54. There were no significant differences between %0 and %25, and also %75 and %100 treated waste water in terms of crude protein content, but there were significant differences between %50 and other treated waste water treatments (except 75% treatments. There were no significant difference between irrigation with different levels of treated waste water in terms of NDF, in vitro DMD, OMD, and D-Value. There were significant differences between forage plants in all studied characteristics, but there were no significant differences on interactions between forage plants and different levels of treated waste water treatments. Forage maize had the highest in vitro DMD at %75 treated waste water and forage sorghum (var. Speed feed had the lowest in vitro DMD at %0 treated waste water treatments with averages of %77.57 and %61.6, respectively. The results indicated that treated waste water increased the percentage of crude

  8. Finding Balance Between Biological Groundwater Treatment and Treated Injection Water

    Energy Technology Data Exchange (ETDEWEB)

    Carlson, Mark A.; Nielsen, Kellin R.; Byrnes, Mark E.; Simmons, Sally A.; Morse, John J.; Geiger, James B.; Watkins, Louis E.; McFee, Phillip M.; Martins, K.

    2015-01-14

    At the U.S. Department of Energy’s Hanford Site, CH2M HILL Plateau Remediation Company operates the 200 West Pump and Treat which was engineered to treat radiological and chemical contaminants in groundwater as a result of the site’s former plutonium production years. Fluidized bed bioreactors (FBRs) are used to remove nitrate, metals, and volatile organic compounds. Increasing nitrate concentrations in the treatment plant effluent and the presence of a slimy biomass (a typical microorganism response to stress) in the FBRs triggered an investigation of nutrient levels in the system. Little, if any, micronutrient feed was coming into the bioreactors. Additionally, carbon substrate (used to promote biological growth) was passing through to the injection wells, causing biological fouling of the wells and reduced specific injectivity. Adjustments to the micronutrient feed improved microorganism health, but the micronutrients were being overfed (particularly manganese) plugging the injection wells further. Injection well rehabilitation to restore specific injectivity required repeated treatments to remove the biological fouling and precipitated metal oxides. A combination of sulfamic and citric acids worked well to dissolve metal oxides and sodium hypochlorite effectively removed the biological growth. Intensive surging and development techniques successfully removed clogging material from the injection wells. Ultimately, the investigation and nutrient adjustments took months to restore proper balance to the microbial system and over a year to stabilize injection well capacities. Carefully tracking and managing the FBRs and well performance monitoring are critical to balancing the needs of the treatment system while reducing fouling mechanisms in the injection wells.

  9. A collection of publications and articles for a light water ultra-safe plant concept

    International Nuclear Information System (INIS)

    Klevans, E.H.

    1988-01-01

    This collection contains reports titled: ''The Penn State Ultra-Safe Reactor Concept; '' ''Ultra Safe Nuclear Power; '' ''Use of the Modular Modeling System, in the Design of the Penn State Advanced Light Water Reactor; '' ''Use of the Modular Modeling System in Severe Transient Analysis of Penn State Advanced Light Water Reactor; '' ''PSU Engineers' Reactor Design May Stop a Future TMI; '' and ''The Penn State Advanced Light Water reactor Concept.''

  10. Shining new light on treating dementia: integrating EEG neurofeedback training and near infrared photobiomodulation (Conference Presentation)

    Science.gov (United States)

    Berman, Marvin H.

    2017-02-01

    Evidence from animal and human studies regarding the biological impact of near infrared light stimulation has significantly increased of late noting the disease modifying properties of photobiomodulation for improving physical and cognitive performance in subjects with a variety of neurodegenerative conditions. Concurrently we see a growing body of literature regarding the efficacy of operant conditioning of EEG amplitude and connectivity in remediating both cognitive and behavioral symptoms of both neuropsychiatric and neurodegenerative disorders including traumatic brain injury, ADHD, PTSD, and dementia. This presentation seeks to outline a treatment model combining these two treatment methods to stop the progression of neurodegeneration using pulsed (10hz), brief (5-20minutes) repeated (1-2x/daily) transcranial and intranasal photobiomodulation with 810nm and 1068nm near infrared phototherapy and operant conditioning of EEG amplitude and coherence. Our initial study on treating dementia with EEG biofeedback (N=37) showed neuroplasticity's potential for modifying cognitive and behavioral symptoms using the evidence from decades of neurological research that never felt the warm touch of a translational researcher's hand. The near infrared interventional studies clarified the order of treatment, i.e., tissue health and renewal were achieved, followed by neural connectivity enhancement. Significant improvements in both immediate and delayed recall and praxis memory as well as executive functioning and behavioral regulation were obtained with each intervention. The inferred synergistic impact of properly combining these approaches is what informs our current clinical applications and future research efforts examining the value of combined treatments for all dementias, parkinson's disease and age-related dry macular degeneration.

  11. Evaluation of 660 nm LED light irradiation on the strategies for treating experimental periodontal intrabony defects.

    Science.gov (United States)

    Tao, Chih-Yun; Lee, Ning; Chang, Hao-Chieh; Yang, Connie; Yu, Xin-Hong; Chang, Po-Chun

    2016-08-01

    This study aims to investigate the therapeutic value of 660 nm light-emitting diode (LED) light irradiation on the strategies for treating experimental periodontal intrabony defects in vivo. Large-sized periodontal intrabony defects were created bilaterally on the mesial aspect of the maxillary second molars of 48 Sprague-Dawley rats, and the rats were equally divided into four treatment groups with primary wound intention (n = 6/treatment/time point), including open flap debridement alone (OD), barrier membrane alone (MB), xenograft alone (BG), and xenograft plus barrier membrane (MG). Each group received daily 0 or 10 J/cm(2) LED light irradiation. The animals were sacrificed after 1 or 4 weeks. The treatment outcome was evaluated by gross observation of wound dehiscence and healing, micro-CT imaging for osteogenesis, and histological assessments for inflammatory cell infiltration and periodontal reattachment. With LED light irradiation, the extent of wound dehiscence was reduced, wound closure was accelerated, epithelial downgrowth was prevented, inflammation was reduced, and periodontal reattachment was promoted in all treatment strategies. Significant reduction of inflammation with LED light irradiation was noted at 1 week in the groups BG and MG (p LED light accelerates mucoperiosteal flap healing and periodontal reattachment. However, the enhancement of osteogenesis appeared to be limited while simultaneously treating with a barrier membrane or xenograft.

  12. Application of Fully Ceramic Microencapsulated Fuels in Light Water Reactors

    International Nuclear Information System (INIS)

    Gehin, Jess C.

    2012-01-01

    This study aims to perform a preliminary evaluation of the feasibility of incorporation of Fully Ceramic Microencapsulated (FCM) fuels in Light Water Reactors (LWRs). In particular pin cell, lattice, and full core analyses are carried out on FCM fuel in a pressurized water reactor. Using uranium-based fuel and transuranic (TRU) based fuel in TRistructural ISOtropic (TRISO) particle form, each fuel design was examined using the SCALE 6.1 analytical suite. In regards to the uranium-based fuel, pin cell calculations were used to determine which fuel material performed best when implemented in the fuel kernel as well as the size of the kernel and surrounding particle layers. The higher physical density of uranium mononitride (UN) proved to be favorable, while the parametric studies showed that the FCM particle fuel design would need roughly 12% additional fissile material in comparison to that of a standard UO2 rod in order to match the lifetime of an 18-month PWR cycle. As part of the fuel assembly design evaluations, fresh feed lattices were modeled to analyze the within-assembly pin power peaking. Also, a color-set array of assemblies was constructed to evaluate power peaking and power sharing between a once-burned and a fresh feed assembly. In regards to the TRU based fuel, lattice calculations were performed to determine an optimal lattice design based on reactivity behavior, pin power peaking, and isotopic content. After obtaining a satisfactory lattice design, feasibility of core designs fully loaded with TRU FCM lattices was demonstrated using the NESTLE three-dimensional core simulator.

  13. Application of fully ceramic microencapsulated fuels in light water reactors

    International Nuclear Information System (INIS)

    Gentry, C.; George, N.; Maldonado, I.; Godfrey, A.; Terrani, K.; Gehin, J.

    2012-01-01

    This study performs a preliminary evaluation of the feasibility of incorporation of Fully Ceramic Microencapsulated (FCM) fuels in light water reactors (LWRs). In particular, pin cell, lattice, and full core analyses are carried out on FCM fuel in a pressurized water reactor (PWR). Using uranium-based fuel and Pu/Np-based fuel in TRistructural isotropic (TRISO) particle form, each fuel design was examined using the SCALE 6.1 analytical suite. In regards to the uranium-based fuel, pin cell calculations were used to determine which fuel material performed best when implemented in the fuel kernel as well as the size of the kernel and surrounding particle layers. The higher fissile material density of uranium mononitride (UN) proved to be favorable, while the parametric studies showed that the FCM particle fuel design with 19.75% enrichment would need roughly 12% additional fissile material in comparison to that of a standard UO 2 rod in order to match the lifetime of an 18-month PWR cycle. As part of the fuel assembly design evaluations, fresh feed lattices were modeled to analyze the within-assembly pin power peaking. Also, a 'color-set' array of assemblies was constructed to evaluate power peaking and power sharing between a once-burned and a fresh feed assembly. In regards to the Pu/Np-based fuel, lattice calculations were performed to determine an optimal lattice design based on reactivity behavior, pin power peaking, and isotopic content. After obtaining a satisfactory lattice design, the feasibility of core designs fully loaded with Pu/Np FCM lattices was demonstrated using the NESTLE three-dimensional core simulator. (authors)

  14. Capital costs of light water reactors: the USA

    International Nuclear Information System (INIS)

    MacKerron, G.

    1979-10-01

    The cost of building a modern nuclear power plant is greater than that of almost any other single civilian project - costs of individual plants are reckoned in hundreds of millions of pounds in the UK, and up to a billion dollars or more in the USA. Hence, depending on the size of nuclear programmes and their funding, escalation of nuclear capital costs may have important economic and social consequences through its effects on overall resource allocation. It is therefore important to analyse the extent and, as far as possible, the sources of cost increases and escalation, in order to see if the experience yields implications for technology policy. The USA has much the greatest experience in nuclear construction: it also has by far the largest amount of published information on the subject of capital costs. As all other countries lack either sufficient experience and/or adequate published cost information, it is impossible to conduct a genuine international comparison, and this paper is confined to an examination of US experience. This paper therefore assembles and evaluates currently available data on light water reactor (PWR and BWR) capital costs in the USA. (author)

  15. Light water reactor pressure isolation valve performance testing

    International Nuclear Information System (INIS)

    Neely, H.H.; Jeanmougin, N.M.; Corugedo, J.J.

    1990-07-01

    The Light Water Reactor Valve Performance Testing Program was initiated by the NRC to evaluate leakage as an indication of valve condition, provide input to Section XI of the ASME Code, evaluate emission monitoring for condition and degradation and in-service inspection techniques. Six typical check and gate valves were purchased for testing at typical plant conditions (550F at 2250 psig) for an assumed number of cycles for a 40-year plant lifetime. Tests revealed that there were variances between the test results and the present statement of the Code; however, the testing was not conclusive. The life cycle tests showed that high tech acoustic emission can be utilized to trend small leaks, that specific motor signature measurement on gate valves can trend and indicate potential failure, and that in-service inspection techniques for check valves was shown to be both feasible and an excellent preventive maintenance indicator. Life cycle testing performed here did not cause large valve leakage typical of some plant operation. Other testing is required to fully understand the implication of these results and the required program to fully implement them. (author)

  16. Controlling radiation fields in siemans designed light water reactors

    Energy Technology Data Exchange (ETDEWEB)

    Riess, R.; Marchl, T. [Siemens Power Generation Group, Erlangen (Germany)

    1995-03-01

    An essential item for the control of radiation fields is the minimization of the use of satellites in the reactor systems of Light Water Reactors (LWRs). A short description of the qualification of Co-replacement materials will be followed by an illustration of the locations where these materials were implemented in Siemens designed LWRs. Especially experiences in PWRs show the immense influence of reduction of cobalt sources on dose rate buildup. The corrosion and the fatique and wear behavior of the replacement materials has not created concern up to now. A second tool to keep occupational radiation doses at a low level in PWRs is the use of the modified B/Li-chemistry. This is practized in Siemens designed plants by keeping the Li level at a max. value of 2 ppm until it reaches a pH (at 300{degrees}C) of {approximately}7.4. This pH is kept constant until the end of the cycle. The substitution of cobalt base alloys and thus the removal of the Co-59 sources from the system had the largest impact on the radiation levels. Nonetheless, the effectiveness of the coolant chemistry should not be neglected either. Several years of successful operation of PWRs with the replacement materials resulted in an occupational radiation exposure which is below 0.5 man-Sievert/plant and year.

  17. Studies of severe accidents in light-water reactors

    International Nuclear Information System (INIS)

    1987-01-01

    From 10 to 12 November 1986 some 80 delegates met under the auspices of the CEC working group on the safety of light-water reactors. The participants from EC Member States were joined by colleagues from Sweden, Finland and the USA and met to discuss the subject of severe accidents in LWRs. Although this seminar had been planned well before Chernobyl, the ''severe-accident-that-really-happened'' made its mark on the seminar. The four main seminar topics were: (i) high source-term accident sequences identified in PSAs, (ii) containment performance, (iii) mitigation of core melt consequences, (iv) severe accident management in LWRs. In addition to the final panel discussion there was also a separate panel discussion on lessons learned from the Chernobyl accident. These proceedings include the papers presented during the seminar and they are arranged following the seminar programme outline. The presentations and discussions of the two panels are not included in the proceedings. The general conclusions and directions following from these two panels were, however, considered in a seminar review paper which was published in the March 1987 issue of Nuclear Engineering International

  18. Technologies for Upgrading Light Water Reactor Outlet Temperature

    Energy Technology Data Exchange (ETDEWEB)

    Daniel S. Wendt; Piyush Sabharwall; Vivek Utgikar

    2013-07-01

    Nuclear energy could potentially be utilized in hybrid energy systems to produce synthetic fuels and feedstocks from indigenous carbon sources such as coal and biomass. First generation nuclear hybrid energy system (NHES) technology will most likely be based on conventional light water reactors (LWRs). However, these LWRs provide thermal energy at temperatures of approximately 300°C, while the desired temperatures for many chemical processes are much higher. In order to realize the benefits of nuclear hybrid energy systems with the current LWR reactor fleets, selection and development of a complimentary temperature upgrading technology is necessary. This paper provides an initial assessment of technologies that may be well suited toward LWR outlet temperature upgrading for powering elevated temperature industrial and chemical processes during periods of off-peak power demand. Chemical heat transformers (CHTs) are a technology with the potential to meet LWR temperature upgrading requirements for NHESs. CHTs utilize chemical heat of reaction to change the temperature at which selected heat sources supply or consume thermal energy. CHTs could directly utilize LWR heat output without intermediate mechanical or electrical power conversion operations and the associated thermodynamic losses. CHT thermal characteristics are determined by selection of the chemical working pair and operating conditions. This paper discusses the chemical working pairs applicable to LWR outlet temperature upgrading and the CHT operating conditions required for providing process heat in NHES applications.

  19. Job-related doses in light water reactors

    International Nuclear Information System (INIS)

    Schnuer, K.

    1993-01-01

    The Treaty of 1957 establishing the European Atomic Energy Community, (EURATOM) was an essential prerequisite for the development of a strong nuclear industry in Europe. Among other things the Treaty provides that the Community shall lay down Basic Safety Standards for the protection of the health of workers and the general public against the dangers arising from ionizing radiation and ensure that they are applied. Following adoption of the Council Directive of 1980, the European Commission defined the basic principles of Justification, Optimization and Limitation to be applied in order to ensure the greatest possible protection of workers and the general public. Subsequently the Commission took initiatives in order to find ways of implementing these three basic principles in practical radiation protection. In 1980 the Commission in close collaboration with the leading nuclear power station operators, set up its own system of 'occupational radiation dose statistics from light water reactors operating in Western Europe'. This was designed for PWRs and BWRs, and the Commission benefited from the experience of neighbouring non-EC countries such as Sweden, Finland, Switzerland and Spain (not yet a member) operating nuclear power stations made by different manufacturers. The paper provides some general information on developments and trends in collective and individual doses to workers in nuclear power stations, based on a unique European databank of approximately 1000 operating reactor years. 9 figs

  20. Radiation-induced embrittlement in light water reactor pressure vessels

    International Nuclear Information System (INIS)

    Gold, R.; McElroy, W.N.

    1987-01-01

    In operating light water reactor (LWR) commercial power plants, neutron radiation induces embrittlement of the pressure vessel (PV) and its support structures. As a consequence, LWR-PV integrity is a primary safety consideration. LWR-PV integry is a significant economic consideration because the PV and its support structures are nonreplaceable power plant components and embrittlement of these components can therefore limit the effective operating lifetime of the plant. In addition to plant life considerations, LWR-PV embrittlement creates significant cycle-to-cycle impact through the restriction of normal heat-up and cool-down reactor operations. Recent LWR-PV benchmark experiments are analyzed. On this bases, it is established that an exponential representation accurately describes the spatial dependence of neutron exposure in LWR-PV. Implications produced by simple exponental behavior are explained and trend-curve models for the predictions of PV embrittelment are derived. These derivations provide for a clearer understanding and assessment of the assumptions underlying these trend-curve models. It is demonstrated that LWR-PV embrittlement possesses significant material dependence. (orig.)

  1. Universal Long-Range Nanometric Bending of Water by Light

    Science.gov (United States)

    Verma, Gopal; Singh, Kamal P.

    2015-10-01

    Resolving mechanical effects of light on fluids has fundamental importance with wide applications. Most experiments to date on optofluidic interface deformation exploited radiation forces exerted by normally incident lasers. However, the intriguing effects of photon momentum for any configuration, including the unique total internal reflection regime, where an evanescent wave leaks above the interface, remain largely unexplored. A major difficulty in resolving nanomechanical effects has been the lack of a sensitive detection technique. Here, we devise a simple setup whereby a probe laser produces high-contrast Newton-ring-like fringes from a sessile water drop. The mechanical action of the photon momentum of a pump beam modulates the fringes, thus allowing us to perform a direct noninvasive measurement of a nanometric bulge with sub-5-nm precision. Remarkably, a laser polarizations and nonlinear enhancement in the bulge near total internal reflection is isolated. In addition, the nanometric bulge is shown to extend far longer, 100 times beyond the pump spot. Our high precision data validate the century-old Minkowski theory for a general angle and offer potential for novel optofluidic devices and noncontact nanomanipulation strategies.

  2. Study on unstable fracture characteristics of light water reactor piping

    International Nuclear Information System (INIS)

    Kurihara, Ryoichi

    1998-08-01

    Many testing studies have been conducted to validate the applicability of the leak before break (LBB) concept for the light water reactor piping in the world. It is especially important among them to clarify the condition that an inside surface crack of the piping wall does not cause an unstable fracture but ends in a stable fracture propagating only in the pipe thickness direction, even if the excessive loading works to the pipe. Pipe unstable fracture tests performed in Japan Atomic Energy Research Institute had been planned under such background, and clarified the condition for the cracked pipe to cause the unstable fracture under monotonous increase loading or cyclic loading by using test pipes with the inside circumferential surface crack. This paper examines the pipe unstable fracture by dividing it into two parts. One is the static unstable fracture that breaks the pipe with the inside circumferential surface crack by increasing load monotonously. Another is the dynamic unstable fracture that breaks the pipe by the cyclic loading. (author). 79 refs

  3. Some critical corrosion issues and mitigation strategies affecting light water reactors

    International Nuclear Information System (INIS)

    Jones, R.L.

    1996-01-01

    Recent corrosion experience in US light water reactor nuclear power plants is reviewed with emphasis on mitigation strategies to control the cost of corrosion to light water reactor operators. The most costly issues have been stress corrosion cracking of stainless steel coolant piping in boiling water reactors and corrosion damage to steam generator tubes in pressurized water reactors. Other significant corrosion problems for both reactor types are briefly reviewed

  4. Effects of Irrigating with Treated Oil and Gas Product Water on Crop Biomass and Soil Permeability

    Energy Technology Data Exchange (ETDEWEB)

    Terry Brown; Jeffrey Morris; Patrick Richards; Joel Mason

    2010-09-30

    Demonstrating effective treatment technologies and beneficial uses for oil and gas produced water is essential for producers who must meet environmental standards and deal with high costs associated with produced water management. Proven, effective produced-water treatment technologies coupled with comprehensive data regarding blending ratios for productive long-term irrigation will improve the state-of-knowledge surrounding produced-water management. Effective produced-water management scenarios such as cost-effective treatment and irrigation will discourage discharge practices that result in legal battles between stakeholder entities. The goal of this work is to determine the optimal blending ratio required for irrigating crops with CBNG and conventional oil and gas produced water treated by ion exchange (IX), reverse osmosis (RO), or electro-dialysis reversal (EDR) in order to maintain the long term physical integrity of soils and to achieve normal crop production. The soils treated with CBNG produced water were characterized with significantly lower SAR values compared to those impacted with conventional oil and gas produced water. The CBNG produced water treated with RO at the 100% treatment level was significantly different from the untreated produced water, while the 25%, 50% and 75% water treatment levels were not significantly different from the untreated water. Conventional oil and gas produced water treated with EDR and RO showed comparable SAR results for the water treatment technologies. There was no significant difference between the 100% treated produced water and the control (river water). The EDR water treatment resulted with differences at each level of treatment, which were similar to RO treated conventional oil and gas water. The 100% treated water had SAR values significantly lower than the 75% and 50% treatments, which were similar (not significantly different). The results of the greenhouse irrigation study found the differences in biomass

  5. Visible-Light-Responsive Graphitic Carbon Nitride: Rational Design and Photocatalytic Applications for Water Treatment.

    Science.gov (United States)

    Zheng, Qinmin; Durkin, David P; Elenewski, Justin E; Sun, Yingxue; Banek, Nathan A; Hua, Likun; Chen, Hanning; Wagner, Michael J; Zhang, Wen; Shuai, Danmeng

    2016-12-06

    Graphitic carbon nitride (g-C 3 N 4 ) has recently emerged as a promising visible-light-responsive polymeric photocatalyst; however, a molecular-level understanding of material properties and its application for water purification were underexplored. In this study, we rationally designed nonmetal doped, supramolecule-based g-C 3 N 4 with improved surface area and charge separation. Density functional theory (DFT) simulations indicated that carbon-doped g-C 3 N 4 showed a thermodynamically stable structure, promoted charge separation, and had suitable energy levels of conduction and valence bands for photocatalytic oxidation compared to phosphorus-doped g-C 3 N 4 . The optimized carbon-doped, supramolecule-based g-C 3 N 4 showed a reaction rate enhancement of 2.3-10.5-fold for the degradation of phenol and persistent organic micropollutants compared to that of conventional, melamine-based g-C 3 N 4 in a model buffer system under the irradiation of simulated visible sunlight. Carbon-doping but not phosphorus-doping improved reactivity for contaminant degradation in agreement with DFT simulation results. Selective contaminant degradation was observed on g-C 3 N 4 , likely due to differences in reactive oxygen species production and/or contaminant-photocatalyst interfacial interactions on different g-C 3 N 4 samples. Moreover, g-C 3 N 4 is a robust photocatalyst for contaminant degradation in raw natural water and (partially) treated water and wastewater. In summary, DFT simulations are a viable tool to predict photocatalyst properties and oxidation performance for contaminant removal, and they guide the rational design, fabrication, and implementation of visible-light-responsive g-C 3 N 4 for efficient, robust, and sustainable water treatment.

  6. Water cooled breeder program summary report (LWBR (Light Water Breeder Reactor) development program)

    Energy Technology Data Exchange (ETDEWEB)

    1987-10-01

    The purpose of the Department of Energy Water Cooled Breeder Program was to demonstrate pratical breeding in a uranium-233/thorium fueled core while producing electrical energy in a commercial water reactor generating station. A demonstration Light Water Breeder Reactor (LWBR) was successfully operated for more than 29,000 effective full power hours in the Shippingport Atomic Power Station. The reactor operated with an availability factor of 76% and had a gross electrical output of 2,128,943,470 kilowatt hours. Following operation, the expended core was examined and no evidence of any fuel element defects was found. Nondestructive assay of 524 fuel rods determined that 1.39 percent more fissile fuel was present at the end of core life than at the beginning, proving that breeding had occurred. This demonstrates the existence of a vast source of electrical energy using plentiful domestic thorium potentially capable of supplying the entire national need for many centuries. To build on the successful design and operation of the Shippingport Breeder Core and to provide the technology to implement this concept, several reactor designs of large breeders and prebreeders were developed for commercial-sized plants of 900--1000 Mw(e) net. This report summarizes the Water Cooled Breeder Program from its inception in 1965 to its completion in 1987. Four hundred thirty-six technical reports are referenced which document the work conducted as part of this program. This work demonstrated that the Light Water Breeder Reactor is a viable alternative as a PWR replacement in the next generation of nuclear reactors. This transition would only require a minimum of change in design and fabrication of the reactor and operation of the plant.

  7. Influence of untreated and bacterial-treated Yamuna water on the ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-09-01

    Sep 1, 2009 ... treated effluent for irrigation fields and grow vegetables ... dilution agar plate technique (Aneja, 2001) and then these cultures ... of bacterial cultures. 5% of stock culture of bacterial consortium was used for the inoculation of sterilized water sample and this water sample was incubated at 37○C for 5 days of ...

  8. Impact of partially treated sewage effluent on the water quality of ...

    African Journals Online (AJOL)

    Impact of partially treated sewage effluent on the water quality of recipient. Epie Creek in the Niger Delta area of Nigeria was investigated experimentally by analysing the physico-chemical and biological characteristics of the surface water samples collected at four (4) sampling stations: at the effluent discharge point (fall ...

  9. Prevalence of enteropathogenic bacteria in treated effluents and receiving water bodies and their potential health risks

    CSIR Research Space (South Africa)

    Teklehaimanot, GZ

    2015-06-01

    Full Text Available . dysenteriae and V. cholerae infection was above the lowest acceptable risk limit of 10(-4) as estimated by the World Health Organization for drinking water. This study showed that the target treated wastewater effluents and their receiving water bodies could...

  10. Removal of micropollutants from aerobically treated grey water via ozone and activated carbon

    NARCIS (Netherlands)

    Hernandez Leal, L.; Temmink, B.G.; Zeeman, G.; Buisman, C.J.N.

    2011-01-01

    Ozonation and adsorption onto activated carbon were tested for the removal micropollutants of personal care products from aerobically treated grey water. MilliQ water spiked with micropollutants (100–1600 µgL-1) was ozonated at a dosing rate of 1.22. In 45 min, this effectively removed (>99%):

  11. Real-time PCR detection of enteric viruses in source water and treated drinking water in Wuhan, China.

    Science.gov (United States)

    Ye, Xiao Yan; Ming, Xing; Zhang, Yong Lu; Xiao, Wen Qing; Huang, Xia Ning; Cao, Yu Guang; Gu, Kang Ding

    2012-09-01

    A total of 48 water samples were collected from six water treatment plants in Wuhan and analyzed by real-time PCR assay for viral identification of enterovirus (EV), rotavirus group A (RVA), human adenovirus (HAdV) as well as human adenovirus subgroup F (HAdVF) during the period from December 2010 to October 2011. HAdV, HAdVF, and RVA were all positively detected in the samples of source water and treated drinking water. EV could be found in 46 % (11/24) of all the source water samples, but only 21 % (5/24) positive in treated drinking water. The concentrations of these three kinds of enteric viruses detected were as follows: HAdV > RVA > EV. The highest removal rate was EV (97 %), followed by RVA (82 %), HAdV (73 %), and HAdVF (72 %). HAdV and RVA have been abundant in untreated river water and finished water after conventional processes of water treatment plants, while bacterial indicators could not be detected in tap water, which met the standard of China for drinking water bacterial quality. Some factors that could affect the accuracy of qPCR detection are also discussed in this study.

  12. Stability analysis of the high performance light water reactor

    Energy Technology Data Exchange (ETDEWEB)

    Ortega Gomez, Tino

    2009-03-15

    In the Generation IV international advanced nuclear reactor development program, the High Performance Light Water Reactor (HPLWR) is one of the most promising candidates. Important features are its inherently high thermodynamic efficiency (of approximately 45 %) and the ability to use existing supercritical water technology which previously has been developed and deployed for fossil fired power plants. Within a HPLWR core, the fluid experiences a drastic change in thermal and transport properties such as density, dynamic viscosity, specific heat and thermal conductivity, as the supercritical water is heated from 280 C to 500 C. The density change substantially exceeds that in a Boiling Water Reactor (i.e., HPLWR: density changes from 780 kg/m{sup 3} to 90 kg/m{sup 3}; BWR: density changes from 750 kg/m{sup 3} to 198 kg/m3). Due to this density change, the HPLWR can be - under certain operation parameters - susceptible to various thermal-hydraulic flow instabilities, which have to be avoided. In this thesis a stability analysis for the HPLWR is presented. This analysis is based on analytical considerations and numerical results, which were obtained by a computer code developed by the author. The heat-up stages of the HPLWR three-pass core are identified in respect to the relevant flow instability phenomena. The modeling approach successfully used for BWR stability analysis is extended to supercritical pressure operation conditions. In particular, a one-dimensional equation set representing the coolant flow of HPLWR fuel assemblies has been implemented in a commercial software named COMSOL to perform steady-state, time-dependent, and modal analyses. An investigation of important static instabilities (i.e., Ledinegg instabilities, flow maldistribution) and Pressure Drop Oscillations (PDO) have been carried out and none were found under operation conditions of the HPLWR. Three types of Density Wave Oscillation (DWO) modes have been studied: the single channel DWO, the

  13. Techniques for detecting the Cherenkov light from cascade showers in water

    Science.gov (United States)

    Khomyakov, V. A.; Bogdanov, A. G.; Kindin, V. V.; Kokoulin, R. P.; Petrukhin, A. A.; Khokhlov, S. S.; Shutenko, V. V.; Yashin, I. I.

    2018-01-01

    The NEVOD Cherenkov water detector (CWD) features a denser lattice of sensitive elements than the existing large-scale CWDs, whereby the spatial distribution of Cherenkov light from cascade showers is sampled with a superior resolution of 0.5 m, which is close to one radiation length for water (36 cm). The experimental techniques for investigating the Cherenkov light generated by particle cascades in water is proposed. The dependence of light intensity on the depth of shower development is for the first time measured at different distances from the shower axis. The results are compared with the Cherenkov light distributions predicted by various model descriptions for the scattering of cascade particles.

  14. Revised accident source terms for light-water reactors

    Energy Technology Data Exchange (ETDEWEB)

    Soffer, L. [Nuclear Regulatory Commission, Washington, DC (United States)

    1995-02-01

    This paper presents revised accident source terms for light-water reactors incorporating the severe accident research insights gained in this area over the last 15 years. Current LWR reactor accident source terms used for licensing date from 1962 and are contained in Regulatory Guides 1.3 and 1.4. These specify that 100% of the core inventory of noble gases and 25% of the iodine fission products are assumed to be instantaneously available for release from the containment. The chemical form of the iodine fission products is also assumed to be predominantly elemental iodine. These assumptions have strongly affected present nuclear air cleaning requirements by emphasizing rapid actuation of spray systems and filtration systems optimized to retain elemental iodine. A proposed revision of reactor accident source terms and some im implications for nuclear air cleaning requirements was presented at the 22nd DOE/NRC Nuclear Air Cleaning Conference. A draft report was issued by the NRC for comment in July 1992. Extensive comments were received, with the most significant comments involving (a) release fractions for both volatile and non-volatile species in the early in-vessel release phase, (b) gap release fractions of the noble gases, iodine and cesium, and (c) the timing and duration for the release phases. The final source term report is expected to be issued in late 1994. Although the revised source terms are intended primarily for future plants, current nuclear power plants may request use of revised accident source term insights as well in licensing. This paper emphasizes additional information obtained since the 22nd Conference, including studies on fission product removal mechanisms, results obtained from improved severe accident code calculations and resolution of major comments, and their impact upon the revised accident source terms. Revised accident source terms for both BWRS and PWRS are presented.

  15. Light Water Reactor Sustainability Program Integrated Program Plan

    Energy Technology Data Exchange (ETDEWEB)

    McCarthy, Kathryn A. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Busby, Jeremy [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Hallbert, Bruce [Idaho National Lab. (INL), Idaho Falls, ID (United States); Bragg-Sitton, Shannon [Idaho National Lab. (INL), Idaho Falls, ID (United States); Smith, Curtis [Idaho National Lab. (INL), Idaho Falls, ID (United States); Barnard, Cathy [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2014-04-01

    Nuclear power has safely, reliably, and economically contributed almost 20% of electrical generation in the United States over the past two decades. It remains the single largest contributor (more than 70%) of non-greenhouse-gas-emitting electric power generation in the United States. Domestic demand for electrical energy is expected to experience a 31% growth from 2009 to 2035. At the same time, most of the currently operating nuclear power plants will begin reaching the end of their initial 20-year extension to their original 40-year operating license for a total of 60 years of operation. Figure E-1 shows projected nuclear energy contribution to the domestic generating capacity. If current operating nuclear power plants do not operate beyond 60 years, the total fraction of generated electrical energy from nuclear power will begin to decline—even with the expected addition of new nuclear generating capacity. The oldest commercial plants in the United States reached their 40th anniversary in 2009. The U.S. Department of Energy Office of Nuclear Energy’s Research and Development Roadmap (Nuclear Energy Roadmap) organizes its activities around four objectives that ensure nuclear energy remains a compelling and viable energy option for the United States. The four objectives are as follows: (1) develop technologies and other solutions that can improve the reliability, sustain the safety, and extend the life of the current reactors; (2) develop improvements in the affordability of new reactors to enable nuclear energy to help meet the Administration’s energy security and climate change goals; (3) develop sustainable nuclear fuel cycles; and (4) understand and minimize the risks of nuclear proliferation and terrorism. The Light Water Reactor Sustainability (LWRS) Program is the primary programmatic activity that addresses Objective 1. This document summarizes the LWRS Program’s plans.

  16. Reliability assurance programme guidebook for advanced light water reactors

    International Nuclear Information System (INIS)

    2001-12-01

    To facilitate the implementation of reliability assurance programmes (RAP) within future advanced reactor programmes and to ensure that the next generation of commercial nuclear reactors achieves the very high levels of safety, reliability and economy which are expected of them, in 1996, the International Atomic Energy Agency (IAEA) established a task to develop a guidebook for reliability assurance programmes. The draft RAP guidebook was prepared by an expert consultant and was reviewed/modified at an Advisory Group meeting (7-10 April 1997) and at a consults meeting (7-10 October 1997). The programme for the RAP guidebook was reported to and guided by the Technical Working Group on Advanced Technologies for Light Water Reactors (TWG-LWR). This guidebook will demonstrate how the designers and operators of future commercial nuclear plants can exploit the risk, reliability and availability engineering methods and techniques developed over the past two decades to augment existing design and operational nuclear plant decision-making capabilities. This guidebook is intended to provide the necessary understanding, insights and examples of RAP management systems and processes from which a future user can derive his own plant specific reliability assurance programmes. The RAP guidebook is intended to augment, not replace, specific reliability assurance requirements defined by the utility requirements documents and by individual nuclear steam supply system (NSSS) designers. This guidebook draws from utility experience gained during implementation of reliability and availability improvement and risk based management programmes to provide both written and diagrammatic 'how to' guidance which can be followed to assure conformance with the specific requirements outlined by utility requirements documents and in the development of a practical and effective plant specific RAP in any IAEA Member State

  17. Light Water Reactor Sustainability Program Integrated Program Plan

    Energy Technology Data Exchange (ETDEWEB)

    Kathryn McCarthy; Jeremy Busby; Bruce Hallbert; Shannon Bragg-Sitton; Curtis Smith; Cathy Barnard

    2013-04-01

    Nuclear power has safely, reliably, and economically contributed almost 20% of electrical generation in the United States over the past two decades. It remains the single largest contributor (more than 70%) of non-greenhouse-gas-emitting electric power generation in the United States. Domestic demand for electrical energy is expected to experience a 31% growth from 2009 to 2035. At the same time, most of the currently operating nuclear power plants will begin reaching the end of their initial 20-year extension to their original 40-year operating license for a total of 60 years of operation. Figure E-1 shows projected nuclear energy contribution to the domestic generating capacity. If current operating nuclear power plants do not operate beyond 60 years, the total fraction of generated electrical energy from nuclear power will begin to decline—even with the expected addition of new nuclear generating capacity. The oldest commercial plants in the United States reached their 40th anniversary in 2009. The U.S. Department of Energy Office of Nuclear Energy’s Research and Development Roadmap (Nuclear Energy Roadmap) organizes its activities around four objectives that ensure nuclear energy remains a compelling and viable energy option for the United States. The four objectives are as follows: (1) develop technologies and other solutions that can improve the reliability, sustain the safety, and extend the life of the current reactors; (2) develop improvements in the affordability of new reactors to enable nuclear energy to help meet the Administration’s energy security and climate change goals; (3) develop sustainable nuclear fuel cycles; and (4) understand and minimize the risks of nuclear proliferation and terrorism. The Light Water Reactor Sustainability (LWRS) Program is the primary programmatic activity that addresses Objective 1. This document summarizes the LWRS Program’s plans.

  18. Factors in the economic viability of advanced light water reactors

    International Nuclear Information System (INIS)

    Matzie, R.A.; Bagnal, C.W.; Rohde, K.R.

    1997-01-01

    Nuclear power currently produces over 20% of the electricity generated in the United States, and a similar number for the entire world. Electricity generated from these nuclear power plants is typically some of the most economical of all sources, and is becoming even more economical with time as utilities focus on reducing production costs. Nevertheless, with the exception of the Asia Pacific region, no new nuclear orders have been placed in many years, and none are planned for the forseeable future. Two reasons for this demise for nuclear power in the western world are usually put forward: the current price of alternative means of electric power generation and the political climate, which tends to be anti-nuclear. The first of these reasons is founded in the low price of natural gas, which has been the preferred fuel for recent power generation additions. These additions have principally been used as peaking units, which are required only at the highest demand periods and not as base load units. The second reason stems from some bad experiences in the post-TMI era, when projects experienced a rapidly changing regulatory environment, long schedule stretchouts, and huge cost overruns. In spite of this relatively poor environment for new nuclear power plants, major programs to develop advanced light water reactors are continuing to keep the nuclear option alive, both in the United States and Europe. These programs are aimed at capturing the lessons learned from past experience, to ensure the success of future nuclear projects. 6 refs., 8 figs., 1 tab

  19. Light Water Reactor Sustainability Program Integrated Program Plan

    Energy Technology Data Exchange (ETDEWEB)

    George Griffith; Robert Youngblood; Jeremy Busby; Bruce Hallbert; Cathy Barnard; Kathryn McCarthy

    2012-01-01

    Nuclear power has safely, reliably, and economically contributed almost 20% of electrical generation in the United States over the past two decades. It remains the single largest contributor (more than 70%) of non-greenhouse-gas-emitting electric power generation in the United States. Domestic demand for electrical energy is expected to experience a 31% growth from 2009 to 2035. At the same time, most of the currently operating nuclear power plants will begin reaching the end of their initial 20-year extension to their original 40-year operating license for a total of 60 years of operation. Figure E-1 shows projected nuclear energy contribution to the domestic generating capacity. If current operating nuclear power plants do not operate beyond 60 years, the total fraction of generated electrical energy from nuclear power will begin to decline - even with the expected addition of new nuclear generating capacity. The oldest commercial plants in the United States reached their 40th anniversary in 2009. The U.S. Department of Energy Office of Nuclear Energy's Research and Development Roadmap (Nuclear Energy Roadmap) organizes its activities around four objectives that ensure nuclear energy remains a compelling and viable energy option for the United States. The four objectives are as follows: (1) develop technologies and other solutions that can improve the reliability, sustain the safety, and extend the life of the current reactors; (2) develop improvements in the affordability of new reactors to enable nuclear energy to help meet the Administration's energy security and climate change goals; (3) develop sustainable nuclear fuel cycles; and (4) understand and minimize the risks of nuclear proliferation and terrorism. The Light Water Reactor Sustainability (LWRS) Program is the primary programmatic activity that addresses Objective 1. This document summarizes the LWRS Program's plans.

  20. 77 FR 15812 - Initial Test Program of Condensate and Feedwater Systems for Light-Water Reactors

    Science.gov (United States)

    2012-03-16

    ... Systems for Light-Water Reactors AGENCY: Nuclear Regulatory Commission. ACTION: Draft regulatory guide... Feedwater Systems for Light- Water Reactors.'' DG-1265 is proposed revision 2 of Regulatory Guide 1.68.1... Plants,'' dated January 1977. This regulatory guide is being revised to: (1) expand the scope of the...

  1. Technology Implementation Plan. Fully Ceramic Microencapsulated Fuel for Commercial Light Water Reactor Application

    Energy Technology Data Exchange (ETDEWEB)

    Snead, Lance Lewis [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Terrani, Kurt A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Powers, Jeffrey J. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Worrall, Andrew [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Robb, Kevin R. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Snead, Mary A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2015-04-01

    This report is an overview of the implementation plan for ORNL's fully ceramic microencapsulated (FCM) light water reactor fuel. The fully ceramic microencapsulated fuel consists of tristructural isotropic (TRISO) particles embedded inside a fully dense SiC matrix and is intended for utilization in commercial light water reactor application.

  2. Technology Implementation Plan. Fully Ceramic Microencapsulated Fuel for Commercial Light Water Reactor Application

    International Nuclear Information System (INIS)

    Snead, Lance Lewis; Terrani, Kurt A.; Powers, Jeffrey J.; Worrall, Andrew; Robb, Kevin R.; Snead, Mary A.

    2015-01-01

    This report is an overview of the implementation plan for ORNL's fully ceramic microencapsulated (FCM) light water reactor fuel. The fully ceramic microencapsulated fuel consists of tristructural isotropic (TRISO) particles embedded inside a fully dense SiC matrix and is intended for utilization in commercial light water reactor application.

  3. Whole blood treated with riboflavin and ultraviolet light: quality assessment of all blood components produced by the buffy coat method.

    Science.gov (United States)

    Schubert, Peter; Culibrk, Brankica; Karwal, Simrath; Serrano, Katherine; Levin, Elena; Bu, Daniel; Bhakta, Varsha; Sheffield, William P; Goodrich, Raymond P; Devine, Dana V

    2015-04-01

    Pathogen inactivation (PI) technologies are currently licensed for use with platelet (PLT) and plasma components. Treatment of whole blood (WB) would be of benefit to the blood banking community by saving time and costs compared to individual component treatment. However, no paired, pool-and-split study directly assessing the impact of WB PI on the subsequently produced components has yet been reported. In a "pool-and-split" study, WB either was treated with riboflavin and ultraviolet (UV) light or was kept untreated as control. The buffy coat (BC) method produced plasma, PLT, and red blood cell (RBC) components. PLT units arising from the untreated WB study arm were treated with riboflavin and UV light on day of production and compared to PLT concentrates (PCs) produced from the treated WB units. A panel of common in vitro variables for the three types of components was used to monitor quality throughout their respective storage periods. PCs derived from the WB PI treatment were of significantly better quality than treated PLT components for most variables. RBCs produced from the WB treatment deteriorated earlier during storage than untreated units. Plasma components showed a 3% to 44% loss in activity for several clotting factors. Treatment of WB with riboflavin and UV before production of components by the BC method shows a negative impact on all three blood components. PLT units produced from PI-treated WB exhibited less damage compared to PLT component treatment. © 2014 AABB.

  4. Effects of light and microbial activity on the degradation of two fluoroquinolone antibiotics in pond water and sediment.

    Science.gov (United States)

    Lin, Juo-Shan; Pan, Hung-Yu; Liu, Shiu-Mei; Lai, Hong-Thih

    2010-07-01

    Enrofloxacin (ENR) and ciprofloxacin (CIP) are two fluoroquinolone (FQ) antibiotics widely used to treat diseases of human beings and cultured animals. These two FQs are usually detected in the effluent of municipal sewage plants and related aquatic environments. The purpose of this study was to understand the fates of ENR and CIP in aquaculture pond water and a sediment slurry in a laboratory-scale experiment. Effects of light and microbial activity on the degradation of these two FQs were investigated. Results indicated that natural irradiation plays a major role in the degradation of ENR and CIP in pond water and the sediment slurry. The 50 % dissipation times (DT(50)) with non-sterile treatment were 0.01 and 18.4 d for ENR, and 0.04 and 17.3 d for CIP in the water and sediment slurry, respectively. On the other hand, the degradation of ENR and CIP under dark conditions was slow or even hindered, and all of their DT(50) values exceeded 100 d. These two FQs degraded faster in the sediment slurry than in pond water under dark conditions. Artificial ultraviolet (UV) and fluorescence light had similar effects on the degradation of ENR in the pond water and sediment slurry. Degradation of CIP was faster with UV than with fluorescence light treatment, while no such difference was found for ENR degradation. CIP was a degradation product of ENR under both light and dark conditions, and DT(50) values for both compounds were shorter in the presence of light. The phenomenon of biodegradation was observed during degradation of CIP in the sediment slurry under natural light.

  5. Minimizing residual aluminum concentration in treated water by tailoring properties of polyaluminum coagulants

    OpenAIRE

    Kimura, Masaoki; Matsui, Yoshihiko; Kondo, Kenta; Ishikawa, Tairyo B.; Matsushita, Taku; Shirasaki, Nobutaka

    2013-01-01

    Aluminum coagulants are widely used in water treatment plants to remove turbidity and dissolved substances. However, because high aluminum concentrations in treated water are associated with increased turbidity and because aluminum exerts undeniable human health effects, its concentration should be controlled in water treatment plants, especially in plants that use aluminum coagulants. In this study, the effect of polyaluminum chloride (PACl) coagulant characteristics on dissolved residual al...

  6. Neutronic study of a light water core reflected with heavy water

    International Nuclear Information System (INIS)

    Golinelli, C.; Tellier, H.

    1967-01-01

    For the design of the high flux reactor with extracted beams, we have performed an experimental study on a light water and highly enriched uranium core surrounded by a thick heavy water reflector. This study was made with a critical facility specially designed. The scope of the measurements was double: i) to check the calculation methods then available ii) to evaluate effects not easily calculated owing to the reactor geometry. The main experiments were the following - criticality measurements for various core geometries - measurement of void and temperature coefficients - distribution of neutron density and fission sources - study of kinetic parameters and calibration of control elements - measurements of spectral indices and of flux perturbations due to the presence in the reflector of channels for the neutron beam extraction. The primary analysis of the experimental results gives generally a satisfactory agreement with calculations and shows that in some cases better hypotheses should be taken. (authors) [fr

  7. Light Reflection from Water Surfaces Perturbed by Falling Rain Droplets

    Science.gov (United States)

    Molesini, Giuseppe; Vannoni, Maurizio

    2009-01-01

    An account of peculiar light patterns produced by reflection in a pool under falling rain droplets was recently reported by Molesini and Vannoni (2008 Eur. J. Phys. 29 403-11). The mathematical approach, however, only covered the case of a symmetrical location of a light source and the observer's eyes with respect to the vertical of the falling…

  8. Restoration of Wadi Aquifers by Artificial Recharge with Treated Waste Water

    KAUST Repository

    Missimer, Thomas M.

    2012-04-26

    Fresh water resources within the Kingdom of Saudi Arabia are a rare and precious commodity that must be managed within a context of integrated water management. Wadi aquifers contain a high percentage of the naturally occurring fresh groundwater in the Kingdom. This resource is currently overused and has become depleted or contaminated at many locations. One resource that could be used to restore or enhance the fresh water resources within wadi aquifers is treated municipal waste water (reclaimed water). Each year about 80 percent of the country\\'s treated municipal waste water is discharged to waste without any beneficial use. These discharges not only represent a lost water resource, but also create a number of adverse environmental impacts, such as damage to sensitive nearshore marine environments and creation of high-salinity interior surface water areas. An investigation of the hydrogeology of wadi aquifers in Saudi Arabia revealed that these aquifers can be used to develop aquifer recharge and recovery (ARR) systems that will be able to treat the impaired-quality water, store it until needed, and allow recovery of the water for transmittal to areas in demand. Full-engineered ARR systems can be designed at high capacities within wadi aquifer systems that can operate in concert with the natural role of wadis, while providing the required functions of additional treatment, storage and recovery of reclaimed water, while reducing the need to develop additional, energy-intensive desalination to meet new water supply demands. © 2012, The Author(s). Ground Water © 2012, National Ground Water Association.

  9. Treatment of ground water contaminated with volatile organic compounds using second generation ultraviolet light technology

    International Nuclear Information System (INIS)

    Lyandres, S.E.; Rees, J.T.; Folsom, E.N.; Boegel, A.J.

    1991-03-01

    Pilot tests, using a second generation ultraviolet (UV) light technology, were run on ground water samples taken f rom two separate aquifers contaminated with volatile organic compounds (VOCS) at the Lawrence Livermore National Laboratory (LLNL) in Alameda County, California. The VOCs included gasoline, TCE, and 1,2-DCA. VOC concentrations in the ground water ranged from 11 to 1,000 ppB. Discharges of treated ground water at LLNL are not to exceed 5 ppb total VOCs under a Federal National Pollution Discharge Elimination System discharge permit. Test results indicated that double-bonded VOCS, including aromatic compounds and TCE, were decomposed quickly and efficiently to low or nondetectable levels (<0.5 ppB, analyzed with a gas chromatograph). An equivalent level of degradation for 1,2-DCA required a moderately higher UV energy input and greater concentrations of additives. Concentrations of peroxide tested ranged between 10 and 60 ppM; however, those above 30 ppM did not significantly increase the rate of VOC destruction

  10. Multi-Application Small Light Water Reactor Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Modro, S.M.; Fisher, J.E.; Weaver, K.D.; Reyes, J.N.; Groome, J.T.; Babka, P.; Carlson, T.M.

    2003-12-01

    The Multi-Application Small Light Water Reactor (MASLWR) project was conducted under the auspices of the Nuclear Energy Research Initiative (NERI) of the U.S. Department of Energy (DOE). The primary project objectives were to develop the conceptual design for a safe and economic small, natural circulation light water reactor, to address the economic and safety attributes of the concept, and to demonstrate the technical feasibility by testing in an integral test facility. This report presents the results of the project. After an initial exploratory and evolutionary process, as documented in the October 2000 report, the project focused on developing a modular reactor design that consists of a self-contained assembly with a reactor vessel, steam generators, and containment. These modular units would be manufactured at a single centralized facility, transported by rail, road, and/or ship, and installed as a series of self-contained units. This approach also allows for staged construction of an NPP and ''pull and replace'' refueling and maintenance during each five-year refueling cycle. Development of the baseline design concept has been sufficiently completed to determine that it complies with the safety requirements and criteria, and satisfies the major goals already noted. The more significant features of the baseline single-unit design concept include: (1) Thermal Power--150 MWt; (2) Net Electrical Output--35 MWe; (3) Steam Generator Type--Vertical, helical tubes; (4) Fuel UO{sub 2}, 8% enriched; (5) Refueling Intervals--5 years; (6) Life-Cycle--60 years. The economic performance was assessed by designing a power plant with an electric generation capacity in the range of current and advanced evolutionary systems. This approach allows for direct comparison of economic performance and forms a basis for further evaluation, economic and technical, of the proposed design and for the design evolution towards a more cost competitive concept

  11. Hospital hydrotherapy pools treated with ultra violet light: bad bacteriological quality and presence of thermophilic Naegleria.

    Science.gov (United States)

    De Jonckheere, J F

    1982-04-01

    The microbiological quality of eight halogenated and two u.v.-treated hydrotherapy pools in hospitals was investigated. The microbiological quality of halogenated hydrotherapy pools was comparable to halogenated public swimming pools, although in some Pseudomonas aeruginosa and faecal pollution indicators were more frequent due to bad management. On the other hand u.v.-treated hydrotherapy pools had very bad microbiological quality. Apart from faecal pollution indicators, P. aeruginosa was present in very high numbers. Halogenated hydrotherapy pools were not highly contaminated with amoebae, and Naegleria spp. were never detected. On the other hand u.v.-treated pools contained very high numbers of thermophilic Naegleria. The Naegleria isolated were identified as N. lovaniensis, a species commonly found in association with N. fowleri. Isoenzyme analysis showed a different type of N. lovaniensis was present in each of two u.v.-treated pools.

  12. Hospital hydrotherapy pools treated with ultra violet light: bad bacteriological quality and presence of thermophilic Naegleria.

    Science.gov (United States)

    De Jonckheere, J. F.

    1982-01-01

    The microbiological quality of eight halogenated and two u.v.-treated hydrotherapy pools in hospitals was investigated. The microbiological quality of halogenated hydrotherapy pools was comparable to halogenated public swimming pools, although in some Pseudomonas aeruginosa and faecal pollution indicators were more frequent due to bad management. On the other hand u.v.-treated hydrotherapy pools had very bad microbiological quality. Apart from faecal pollution indicators, P. aeruginosa was present in very high numbers. Halogenated hydrotherapy pools were not highly contaminated with amoebae, and Naegleria spp. were never detected. On the other hand u.v.-treated pools contained very high numbers of thermophilic Naegleria. The Naegleria isolated were identified as N. lovaniensis, a species commonly found in association with N. fowleri. Isoenzyme analysis showed a different type of N. lovaniensis was present in each of two u.v.-treated pools. Images Plate 1 PMID:7061835

  13. Light Water Reactor Sustainability Program. Digital Architecture Requirements

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, Kenneth [Idaho National Lab. (INL), Idaho Falls, ID (United States); Oxstrand, Johanna [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2015-03-01

    The Digital Architecture effort is a part of the Department of Energy (DOE) sponsored Light-Water Reactor Sustainability (LWRS) Program conducted at Idaho National Laboratory (INL). The LWRS program is performed in close collaboration with industry research and development (R&D) programs that provides the technical foundations for licensing and managing the long-term, safe, and economical operation of current nuclear power plants (NPPs). One of the primary missions of the LWRS program is to help the U.S. nuclear industry adopt new technologies and engineering solutions that facilitate the continued safe operation of the plants and extension of the current operating licenses. Therefore, a major objective of the LWRS program is the development of a seamless digital environment for plant operations and support by integrating information from plant systems with plant processes for nuclear workers through an array of interconnected technologies. In order to get the most benefits of the advanced technology suggested by the different research activities in the LWRS program, the nuclear utilities need a digital architecture in place to support the technology. A digital architecture can be defined as a collection of information technology (IT) capabilities needed to support and integrate a wide-spectrum of real-time digital capabilities for nuclear power plant performance improvements. It is not hard to imagine that many processes within the plant can be largely improved from both a system and human performance perspective by utilizing a plant wide (or near plant wide) wireless network. For example, a plant wide wireless network allows for real time plant status information to easily be accessed in the control room, field workers’ computer-based procedures can be updated based on the real time plant status, and status on ongoing procedures can be incorporated into smart schedules in the outage command center to allow for more accurate planning of critical tasks. The goal

  14. Light Water Reactor Sustainability Program: Integrated Program Plan

    International Nuclear Information System (INIS)

    2016-02-01

    proliferation and terrorism. The Light Water Reactor Sustainability (LWRS) Program is the primary programmatic activity that addresses Objective 1. This document summarizes the LWRS Program's plans. For the LWRS Program, sustainability is defined as the ability to maintain safe and economic operation of the existing fleet of nuclear power plants for a longer-than-initially-licensed lifetime. It has two facets with respect to long-term operations: (1) manage the aging of plant systems, structures, and components so that nuclear power plant lifetimes can be extended and the plants can continue to operate safely, efficiently, and economically; and (2) provide science-based solutions to the industry to implement technology to exceed the performance of the current labor-intensive business model.

  15. Light Water Reactor Sustainability Program: Integrated Program Plan

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    2017-05-01

    proliferation and terrorism. The Light Water Reactor Sustainability (LWRS) Program is the primary programmatic activity that addresses Objective 1. This document summarizes the LWRS Program’s plans. For the LWRS Program, sustainability is defined as the ability to maintain safe and economic operation of the existing fleet of nuclear power plants for a longer-than-initially-licensed lifetime. It has two facets with respect to long-term operations: (1) manage the aging of plant systems, structures, and components so that nuclear power plant lifetimes can be extended and the plants can continue to operate safely, efficiently, and economically; and (2) provide science-based solutions to the industry to implement technology to exceed the performance of the current labor-intensive business model.

  16. Hospital hydrotherapy pools treated with ultra violet light: bad bacteriological quality and presence of thermophilic Naegleria.

    OpenAIRE

    De Jonckheere, J. F.

    1982-01-01

    The microbiological quality of eight halogenated and two u.v.-treated hydrotherapy pools in hospitals was investigated. The microbiological quality of halogenated hydrotherapy pools was comparable to halogenated public swimming pools, although in some Pseudomonas aeruginosa and faecal pollution indicators were more frequent due to bad management. On the other hand u.v.-treated hydrotherapy pools had very bad microbiological quality. Apart from faecal pollution indicators, P. aeruginosa was pr...

  17. Treating cooling pond water for Wabamun Lake level mitigation project in Alberta

    Energy Technology Data Exchange (ETDEWEB)

    Anon

    2004-05-01

    Dealing with the challenge of recharging Wabamun Lake by treating nearby cooling pond water, fed by the North Saskatchewan River, and returning it to the lake, is discussed. To deal with the problem, TransAlta Utilities constructed a treatment plant in 1997 next to the 2,029 MW Sundance power plant to mitigate the effect the power plant's ongoing and historical effect on the lake's water level. The objective of the treatment plant is to treat cooling pond water and return it to the lake to raise water levels there, which have been significantly reduced over the last 25 years mostly by power plant intake, but also by lack of rainfall, surface runoff, and natural evaporation. At the Treatment Facility the water to be treated is first chlorinated to kill zooplankton, algae and bacteria, followed by adjusting the pH using sulfuric acid. Alum coagulant is used to destabilize colour, particles and colloids. The next step is feeding the water to the Actiflo clarifiers which use microsand to provide increased surface area for floc attachment, and to act as ballast. Clarified water from the Actiflo system is then fed to to the Dusenflo filters to remove the largest particles of suspended solids, and through a finer sand media to remove the remaining turbidity, colour and bacteria. Thiosulfate is used in the ozonation system to inactivate any remaining bacteria and zooplankton in the filtered water, before discharging it to the lake. The cooling towers, which are part of the system, ensure that the treated water returned to the lake is kept at a constant temperature, varying no more than three degrees C from the lake water temperature. 3 figs.

  18. Treating cooling pond water for Wabamun Lake level mitigation project in Alberta

    International Nuclear Information System (INIS)

    Anon

    2004-01-01

    Dealing with the challenge of recharging Wabamun Lake by treating nearby cooling pond water, fed by the North Saskatchewan River, and returning it to the lake, is discussed. To deal with the problem, TransAlta Utilities constructed a treatment plant in 1997 next to the 2,029 MW Sundance power plant to mitigate the effect the power plant's ongoing and historical effect on the lake's water level. The objective of the treatment plant is to treat cooling pond water and return it to the lake to raise water levels there, which have been significantly reduced over the last 25 years mostly by power plant intake, but also by lack of rainfall, surface runoff, and natural evaporation. At the Treatment Facility the water to be treated is first chlorinated to kill zooplankton, algae and bacteria, followed by adjusting the pH using sulfuric acid. Alum coagulant is used to destabilize colour, particles and colloids. The next step is feeding the water to the Actiflo clarifiers which use microsand to provide increased surface area for floc attachment, and to act as ballast. Clarified water from the Actiflo system is then fed to to the Dusenflo filters to remove the largest particles of suspended solids, and through a finer sand media to remove the remaining turbidity, colour and bacteria. Thiosulfate is used in the ozonation system to inactivate any remaining bacteria and zooplankton in the filtered water, before discharging it to the lake. The cooling towers, which are part of the system, ensure that the treated water returned to the lake is kept at a constant temperature, varying no more than three degrees C from the lake water temperature. 3 figs

  19. Visible Light Responsive Catalyst for Air & Water Purification

    Data.gov (United States)

    National Aeronautics and Space Administration — The objective for this project was to investigate and develop viable approaches to render the normally UV-activated titanium dioxide (TiO2) catalyst visible light...

  20. Light penetration in the coastal waters off Goa

    Digital Repository Service at National Institute of Oceanography (India)

    Sathyendranath, S.; Varadachari, V.V.R.

    Observations of light penetration have been carried out at 6 stations along the Goa Coast, India, for different periods during 1975-76, using a submarine photometer. Seasonal and spatial variations in the values of irradiance attenuation coefficient...

  1. Visible Light Responsive Catalyst for Air Water Purification Project

    Science.gov (United States)

    Wheeler, Raymond M.

    2014-01-01

    Investigate and develop viable approaches to render the normally UV-activated TIO2 catalyst visible light responsive (VLR) and achieve high and sustaining catalytic activity under the visible region of the solar spectrum.

  2. Alkaline hydrogen peroxide treatment for TiO{sub 2} nanoparticles with superior water-dispersibility and visible-light photocatalytic activity

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Chung-Yi; Tu, Kuan-Ju; Lo, Yu-Shiu [Department of Biomedical Engineering and Environmental Sciences, College of Nuclear Science, National Tsing Hua University, Hsinchu 30013, Taiwan (China); Pang, Yean Ling [Department of Chemical Engineering, Lee Kong Chian Faculty of Engineering and Science, Universiti Tunku Abdul Rahman, 43000 Kajang, Selangor (Malaysia); Wu, Chien-Hou, E-mail: chwu@mx.nthu.edu.tw [Department of Biomedical Engineering and Environmental Sciences, College of Nuclear Science, National Tsing Hua University, Hsinchu 30013, Taiwan (China)

    2016-09-15

    Alkaline hydrogen peroxide treatment was proposed as a simple and green way to improve the performance of commercial TiO{sub 2} powder for water-dispersibility and visible-light photocatalytic activity on the degradation of dye pollutants. The performance of treated TiO{sub 2} was evaluated as a function of NaOH concentration, H{sub 2}O{sub 2} concentration, and treatment time. The optimal conditions were determined to be 24 h in 100 mM H{sub 2}O{sub 2} and 8 M NaOH. The treated samples were characterized by Raman spectroscopy, high-resolution transmission electron microscopy (HR-TEM), X-ray photoelectron spectroscopy (XPS), dynamic light scattering (DLS), Fourier transform infrared spectroscopy (FTIR), and ultraviolet–visible spectrophotometry. The analysis revealed that the crystal structure, morphology, and absorption band gap were retained, but the surface of the treated TiO{sub 2} was dramatically changed. The treated TiO{sub 2} was highly dispersible with a uniform hydrodynamic size of 41 ± 12 nm and stable over months in water at pH 3 without any stabilizing ligand and could significantly enhance the visible-light photodegradation of dye pollutants. The superior performance might be attributed to the formation of abundant surface hydroxyl groups. This treatment paves the way for developing water-dispersible TiO{sub 2} with superior visible-light induced photocatalytic degradation of dye pollutants without any complicated and expensive surface modification. - Highlights: • Alkaline hydrogen peroxide is proposed to treat commercial TiO{sub 2} powder. • The treated TiO{sub 2} powder exhibits superior water-dispersibility with a uniform size distribution. • The treated TiO{sub 2} powder can significantly enhance the visible-light photodegradation of dyes.

  3. Lighting

    Data.gov (United States)

    Federal Laboratory Consortium — Lighting Systems Test Facilities aid research that improves the energy efficiency of lighting systems. • Gonio-Photometer: Measures illuminance from each portion of...

  4. Removal of nitrate from water by adsorption onto zinc chloride treated activated carbon

    DEFF Research Database (Denmark)

    Bhatnagar, A.; Ji, M.; Choi, Y.H.

    2008-01-01

    Adsorption study with untreated and zinc chloride (ZnCl2) treated coconut granular activated carbon (GAC) for nitrate removal from water has been carried out. Untreated coconut GAC was treated with ZnCl2 and carbonized. The optimal conditions were selected by studying the influence of process...... variables such as chemical ratio and activation temperature. Experimental results reveal that chemical weight ratio of 200% and temperature of 500 degrees C was found to be optimum for the maximum removal of nitrate from water. Both untreated and ZnCl2 treated coconut GACs were characterized by scanning...... electron microscopy (SEM), Brunauer Emmett Teller (BET) N-2-gas adsorption, surface area and Energy Dispersive X-Ray (EDX) analysis. The comparison between untreated and ZnCl2 treated GAC indicates that treatment with ZnCl2 has significantly improved the adsorption efficacy of untreated GAC. The adsorption...

  5. Inactivation of Escherichia coli O157:H7 using ultraviolet light-treated bacteriophages.

    Science.gov (United States)

    Hudson, J A; Billington, C; Premaratne, A; On, S L W

    2016-01-01

    Escherichia coli O157:H7 causes serious foodborne infections warranting the development of effective control measures. One control option is to use bacteriophages (phages), which are regarded as safe to humans and an environmentally friendly alternative to chemical antimicrobials. One of the few remaining safety concerns is the potential for phages to facilitate genetic exchange between bacteria so resulting in undesirable mobilisation of genes. UV treatment of phages causes a rapid loss in their ability to replicate, while maintaining their antibacterial activity, and so the use of UV-treated phages could be an alternative to the use of viable phages. Data presented here show the inactivation of E. coli O157:H7 by UV-treated phages in milk and on the surface of raw and cooked meat. A minimum concentration of approximately 10(5) PFU cm(-2) (pre-UV treatment titre) of UV-treated phages was required before inactivation of E. coli O157:H7 on the surface of meat was measurable, and 1-2 log10 CFU cm(-2) reductions were typically obtained at concentrations of around 10(7) UV-treated phages cm(-2) (pre-UV treatment titre). Inactivation of E. coli O157:H7 by UV-treated phages was less than that for untreated phages. The production of UV-treated phages was not optimised and it is possible that better reductions in pathogen concentration could be achieved for the same input UV-treated phages concentrations. © The Author(s) 2014.

  6. Wetlands receiving water treated with coagulants improve water quality by removing dissolved organic carbon and disinfection byproduct precursors.

    Science.gov (United States)

    Hansen, Angela M; Kraus, Tamara E C; Bachand, Sandra M; Horwath, William R; Bachand, Philip A M

    2018-05-01

    Constructed wetlands are used worldwide to improve water quality while also providing critical wetland habitat. However, wetlands have the potential to negatively impact drinking water quality by exporting dissolved organic carbon (DOC) that upon disinfection can form disinfection byproducts (DBPs) like trihalomethanes (THMs) and haloacetic acids (HAAs). We used a replicated field-scale study located on organic rich soils in California's Sacramento-San Joaquin Delta to test whether constructed flow-through wetlands which receive water high in DOC that is treated with either iron- or aluminum-based coagulants can improve water quality with respect to DBP formation. Coagulation alone removed DOC (66-77%) and THM (67-70%) precursors, and was even more effective at removing HAA precursors (77-90%). Passage of water through the wetlands increased DOC concentrations (1.5-7.5mgL -1 ), particularly during the warmer summer months, thereby reversing some of the benefits from coagulant addition. Despite this addition, water exiting the wetlands treated with coagulants had lower DOC and DBP precursor concentrations relative to untreated source water. Benefits of the coagulation-wetland systems were greatest during the winter months (approx. 50-70% reduction in DOC and DBP precursor concentrations) when inflow water DOC concentrations were higher and wetland DOC production was lower. Optical properties suggest DOC in this system is predominantly comprised of high molecular weight, aromatic compounds, likely derived from degraded peat soils. Published by Elsevier B.V.

  7. NO treated TiO2 as an efficient visible light photocatalyst for NO removal

    International Nuclear Information System (INIS)

    Ai Zhihui; Zhu Linli; Lee Shuncheng; Zhang Lizhi

    2011-01-01

    Highlights: → We reported that nitrogen doped TiO 2 could be achieved via thermal treatment of Degussa P25 TiO 2 in NO atmosphere directly (P25-NO). → In comparison with that of P25, the P25-NO exhibited significantly enhanced photocatalytic activities under visible light irradiation (λ > 420 nm) for gaseous NO removal. → We proposed a possible mechanism for the enhanced visible light driven photocatalytic oxidation process over the interstitial N doping P25 samples. - Abstract: In this study, we report that nitrogen doped TiO 2 could be achieved via thermal treatment of Degussa P25 TiO 2 in NO atmosphere directly (P25-NO). The samples were characterized with XRD, XPS, and FT-IR. The characterization results suggested that nitrogen species were interstitially doped in P25-NO during the NO thermal treatment process. In comparison with P25, the P25-NO exhibited significantly enhanced photocatalytic activities under visible light irradiation (λ > 420 nm) for gaseous NO removal. On the basis of electronic band structure theory, we proposed a possible mechanism for the enhanced visible light driven photocatalytic oxidation process over the interstitial N doping P25-NO samples. This work could not only deepen understanding of the enhanced photoactivity originated from interstitial N doping in TiO 2 , but also provide a facile route to prepare nitrogen doped TiO 2 for environmental and energy applications.

  8. Control of a high temperature supercritical pressure light water cooled and moderated reactor with water rods

    International Nuclear Information System (INIS)

    Ishiwatari, Yuki; Oka, Yoshiaki; Koshizuka, Seiichi

    2003-01-01

    The plant system of a supercritical pressure light water reactor (SCR) is once-through direct cycle. The whole coolant from the feedwater pumps is driven to the turbines. The core flow rate is less than 1/7 of that of a boiling water reactor. In the present design of the high temperature thermal reactor (SCLWR-H), the fuel assemblies contain many water rods in which the coolant flows downward. The stepwise responses of the SCLWR-H are analyzed against perturbations without a control system. Based on these analyses, a control system of the SCLWR-H is designed. The pressure is controlled by the turbine control valves. The main steam temperature is controlled by the feedwater pumps. The reactor power is controlled by the control rods. The control parameters are optimized by the test calculations to satisfy the criteria of both fast convergence and stability. The reactor is controlled stably with the designed control systems against various perturbations, such as setpoint change of the pressure, the main steam temperature and the core power, decrease in the feedwater temperature, and decrease in the feedwater flow rate. (author)

  9. Removal of micropollutants from aerobically treated grey water via ozone and activated carbon.

    Science.gov (United States)

    Hernández-Leal, L; Temmink, H; Zeeman, G; Buisman, C J N

    2011-04-01

    Ozonation and adsorption onto activated carbon were tested for the removal micropollutants of personal care products from aerobically treated grey water. MilliQ water spiked with micropollutants (100-1600 μgL(-1)) was ozonated at a dosing rate of 1.22. In 45 min, this effectively removed (>99%): Four parabens, bisphenol-A, hexylcinnamic aldehyde, 4-methylbenzylidene-camphor (4MBC), benzophenone-3 (BP3), triclosan, galaxolide and ethylhexyl methoxycinnamate. After 60 min, the removal efficiency of benzalkonium chloride was 98%, tonalide and nonylphenol 95%, octocrylene 92% and 2-phenyl-5-benzimidazolesulfonic acid (PBSA) 84%. Ozonation of aerobically treated grey water at an applied ozone dose of 15 mgL(-1), reduced the concentrations of octocrylene, nonylphenol, triclosan, galaxolide, tonalide and 4-methylbenzylidene-camphor to below limits of quantification, with removal efficiencies of at least 79%. Complete adsorption of all studied micropollutants onto powdered activated carbon (PAC) was observed in batch tests with milliQ water spiked with 100-1600 μgL(-1) at a PAC dose of 1.25 gL(-1) and a contact time of 5 min. Three granular activated carbon (GAC) column experiments were operated to treat aerobically treated grey water. The operation of a GAC column with aerobically treated grey water spiked with micropollutants in the range of 0.1-10 μgL(-1) at a flow of 0.5 bed volumes (BV)h(-1) showed micropollutant removal efficiencies higher than 72%. During the operation time of 1728 BV, no breakthrough of TOC or micropollutants was observed. Removal of micropollutants from aerobically treated grey water was tested in a GAC column at a flow of 2 BVh(-1). Bisphenol-A, triclosan, tonalide, BP3, galaxolide, nonylphenol and PBSA were effectively removed even after a stable TOC breakthrough of 65% had been reached. After spiking the aerobically treated effluent with micropollutants to concentrations of 10-100 μgL(-1), efficient removal to below limits of quantification

  10. Investigation the Stability of Treated Water Produced from Six Stations in Babylon

    Directory of Open Access Journals (Sweden)

    Hadeel Ali Abdulhussein

    2017-11-01

    Full Text Available Corrosion and scaling are mutual problems appeared in water distribution systems. The strictness of such problems depends on the quality of the water conveyed and the characteristics of the pipeline material. For solving and minimizing such problems, the probability of corrosivity and scaling of water as well as the factors effecting them should be investigated.  Four water stability indices (Langlier Saturation Index (LSI, Ryznar Stability Index (RSI, Pockurius Scaling Index (PSI, and Aggressive Index (AIwere used to investigate the stability of treated water from six selected water treatment plants in Babylon province (Al-Hillah Al-Jadeed, Al-Hillah Al-Kadeem, Al-Taiyara, Al-Hussain, Al-Mahaweel and Al-Hashmia during 2009-2013. According to LSI the treated water quality of the all stations was oversaturated with CaCO3 during the whole studied period (positive LSI values with a potential of forming a protective layer from calcium carbonate. RSI, PSI and AI results displayed that the water quality was of moderately corrosive which can be considered not harmful for water distribution systems.

  11. Gill histopathological alterations in Nile tilapia, Oreochromis niloticus exposed to treated sewage Water

    Directory of Open Access Journals (Sweden)

    António Fontaínhas-Fernandes

    2008-10-01

    Full Text Available Adult Nile tilapia, Oreochromis niloticus, of both sexes were exposed in wastewater from a sewage treatment plant for a period of 4 days. Gill samples were collected after 24, 48, 72 and 96 h and histopathological changes were analyzed by light and scanning electronic microscopy. Gill epithelium of control O. niloticus (freshwater group was similar to that of other teleosts, while histopathological lesions were observed in exposed fishes. The main histopathological changes were edema, lifting of lamellar and filamentar epithelia and lamellar fusion. Cell proliferation with consequent thickening of the filament epithelium was also found in fishes exposed to the treated sewage water. The severity of the lesions increased with the time of exposure, namely the hyperplasia of the epithelial cells with proliferation of filamentar epithelium and fusion of lamellae observed at 96 h. Additionally, several histopathological results obtained by light microscopy were confirmed through scanning microscopy.Tilápias adultas, Oreochromis niloticus, de ambos os sexos foram expostas em águas residuais de uma estação de tratamento de esgoto durante 4 dias. Amostras de brânquia foram recolhidas após 24, 48, 72 e 96 h e as alterações histopatológicas foram analisadas por microscopia óptica e eletrônica de varredura. O epitélio da brânquia do grupo controle apresentou uma morfologia similar à de outros peixes teleosteos, enquanto foram observadas lesões nos peixes expostos. As principais alterações histopatológicas foram edema, destacamento dos epitélios lamelar e filamentar e fusão lamelar. Os peixes expostos às águas residuais mostraram também proliferação celular com consequente aumento da espessura do filamento branquial. A severidade das lesões aumentou com o tempo de exposição, nomeadamente a hiperplasia das células epiteliais com proliferação do epitélio filamentar e fusão das lamelas observadas preferencialmente às 96 h

  12. How to treat Alzheimer’s with new LED light technology

    DEFF Research Database (Denmark)

    Nguyen, Ngoc Mai; Petersen, Paul Michael; Broeng, Jes

    We have developed a new therapeutic LED lamp that modulates with 40 Hz the neuron responses in different parts of the brain without affecting the human vision. The lamp may in the future be used to treat patients with Alzheimer’s disease.......We have developed a new therapeutic LED lamp that modulates with 40 Hz the neuron responses in different parts of the brain without affecting the human vision. The lamp may in the future be used to treat patients with Alzheimer’s disease....

  13. Light

    DEFF Research Database (Denmark)

    Prescott, N.B.; Kristensen, Helle Halkjær; Wathes, C.M.

    2004-01-01

    This chapter presents the effect of artificial light environments (light levels, colour, photoperiod and flicker) on the welfare of broilers in terms of vision, behaviour, lameness and mortality......This chapter presents the effect of artificial light environments (light levels, colour, photoperiod and flicker) on the welfare of broilers in terms of vision, behaviour, lameness and mortality...

  14. Removal of fluorescence and ultraviolet absorbance of dissolved organic matter in reclaimed water by solar light.

    Science.gov (United States)

    Wu, Qianyuan; Li, Chao; Wang, Wenlong; He, Tao; Hu, Hongying; Du, Ye; Wang, Ting

    2016-05-01

    Storing reclaimed water in lakes is a widely used method of accommodating changes in the consumption of reclaimed water during wastewater reclamation and reuse. Solar light serves as an important function in degrading pollutants during storage, and its effect on dissolved organic matter (DOM) was investigated in this study. Solar light significantly decreased the UV254 absorbance and fluorescence (FLU) intensity of reclaimed water. However, its effect on the dissolved organic carbon (DOC) value of reclaimed water was very limited. The decrease in the UV254 absorbance intensity and FLU excitation-emission matrix regional integration volume (FLU volume) of reclaimed water during solar light irradiation was fit with pseudo-first order reaction kinetics. The decrease of UV254 absorbance was much slower than that of the FLU volume. Ultraviolet light in solar light had a key role in decreasing the UV254 absorbance and FLU intensity during solar light irradiation. The light fluence-based removal kinetic constants of the UV254 and FLU intensity were independent of light intensity. The peaks of the UV254 absorbance and FLU intensity with an apparent molecular weight (AMW) of 100Da to 2000Da decreased after solar irradiation, whereas the DOC value of the major peaks did not significantly change. Copyright © 2015. Published by Elsevier B.V.

  15. An environmentalist's perspective on alternatives to pump and treat for ground water remediation

    International Nuclear Information System (INIS)

    Ross, D.L.

    1993-01-01

    Pump and treat is far-and-away the most prevalent technique to remediate contaminated ground water. There is, however, a growing awareness of the limitations of this remediation method to achieve either background or health-based water quality standards, particularly for petroleum hydrocarbon constituents. Given these limitations, this paper explores advantages and disadvantages of some remediation alternatives from an environmentalist's perspective. They are: Do it anyway; Quit; Use supplementary remediation technology; Set alternative concentration standards; and Transfer resources to pollution prevention

  16. Solar light irradiation significantly reduced cytotoxicity and disinfection byproducts in chlorinated reclaimed water.

    Science.gov (United States)

    Lv, Xiao-Tong; Zhang, Xue; Du, Ye; Wu, Qian-Yuan; Lu, Yun; Hu, Hong-Ying

    2017-11-15

    Chlorinated reclaimed water is widely used for landscaping and recreational purposes, resulting in human exposure to toxic disinfection byproducts. Although the quality of chlorinated reclaimed water might be affected by sunlight during storage, the effects of solar light irradiation on the toxicity remain unknown. This study investigated the changes in cytotoxicity and total organic halogen (TOX) of chlorinated reclaimed water exposed to solar light. Irradiation with solar light for 12 h was found to significantly reduce the cytotoxicity of chlorinated reclaimed water by about 75%, with ultraviolet light being responsible for the majority of this reduction. Chlorine residual in reclaimed water tended to increase the cytotoxicity, and the synergy between solar light and free chlorine could not enhance the reduction of cytotoxicity. Adding hydroxyl radical scavengers revealed that the contribution of hydroxyl radical to cytotoxicity reduction was limited. Solar light irradiation concurrently reduced TOX. The low molecular weight (cytotoxicity and TOX in chlorinated reclaimed water. Detoxification of the low molecular weight fraction by light irradiation was mainly a result of TOX dehalogenation, while detoxification of the high molecular weight (>1 kDa) fraction was probably caused by photoconversion from high toxic TOX to low toxic TOX. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Critical behavior of 2,6-dimethylpyridine-water: Measurements of specific heat, dynamic light scattering, and shear viscosity

    DEFF Research Database (Denmark)

    Mirzaev, S. Z.; Behrends, R.; Heimburg, Thomas Rainer

    2006-01-01

    2,6-dimethylpyridine-water, specific heat, dynamic light scattering, shear viscosity Udgivelsesdato: 14 April......2,6-dimethylpyridine-water, specific heat, dynamic light scattering, shear viscosity Udgivelsesdato: 14 April...

  18. A novel water-assisted pulsed light processing for decontamination of blueberries.

    Science.gov (United States)

    Huang, Yaoxin; Chen, Haiqiang

    2014-06-01

    Sample heating and shadowing effect have limited the application of pulsed light (PL) technology for decontamination of fresh produce. In this study, a novel setup using water-assisted PL processing was developed to overcome these limitations. Blueberries inoculated with Escherichia coli O157:H7 or Salmonella were either treated with PL directly (dry PL treatment) or immersed in agitated water during the PL treatment (wet PL treatment) for 5-60 s. Although both pathogens were effectively inactivated by the dry PL treatments, the appearance of the blueberries was adversely affected and a maximum temperature of 64.8 °C on the blueberry surface was recorded. On the other hand, the visual appearance of blueberries remained unchanged after wet PL treatments and sample heating was significantly reduced. The wet PL treatments were more effective than chlorine washing on inactivating both pathogens. After a 60-s wet PL treatment, the populations of E. coli O157:H7 inoculated on calyx and skin of blueberries were reduced by 3.0 and >5.8 log CFU/g, respectively. Salmonella on blueberry calyx and skin was reduced by 3.6 and >5.9 log CFU/g, respectively. No viable bacterial cells were recovered from the water used in the wet PL treatments, demonstrating that this setup could prevent the risk of cross-contamination during fresh produce washing. Our results suggest that this new water-assisted PL treatment could be a potential non-chemical alternative (residue free) to chlorine washing since it is both more effective and environmentally friendly than chlorine washing. Copyright © 2013 Elsevier Ltd. All rights reserved.

  19. The management plan of liquid effluent in Korean advanced light water reactor

    International Nuclear Information System (INIS)

    Kim, S. H.; Lim, H. S.; Jeong, D. W.; Jeong, D. Y.

    2001-01-01

    Non-radioactive liquid effluent in Korean Advanced Light Water Reactor is transferred and treated in centralized waste treatment facility after the radioactivity in effluent is checked within power block. The liquid effluent from centralized waste treatment facility will be discharged by way of discharge canal in order to be in the sufficient condition. As a result of investigating the radiation monitoring design in accordance with 20 provisions by Korean Regulatory Authority, each effluent radiation monitoring with 20 provisions by Korean Regulatory Authority, each effluent radiation monitoring design satisfies the regulatory guideline. In relation to sampling and analyses, most systems satisfy the regulatory guideline except for some effluents from turbine building. And, though sampling and analyses are performed after radioactivity is monitored at each system in turbine building, these exceptions in turbine building effluents are expected to cause no significant problems because radioactivity is monitored by direct or indirect methods prior to release from turbine building. Integrated monitoring on liquid effluent from the centralized waste water treatment facility is not necessary because radiation monitoring, sampling and analyses on each system within power block are performed, and operational effectiveness compared with cost according to adding the radiation monitoring equipment is too low. So, whether the radiation monitoring in this effluent is reflected on design or not is planned to be determined through discussion with regulatory authority

  20. Water cooling of high power light emitting diode

    DEFF Research Database (Denmark)

    Sørensen, Henrik

    2012-01-01

    The development in light technologies for entertainment is moving towards LED based solutions. This progress is not without problems, when more than a single LED is used. The amount of generated heat is often in the same order as in a conventional discharge lamp, but the allowable operating...

  1. Quality of Drinking Water Treated at Point of Use in Residential Healthcare Facilities for the Elderly.

    Science.gov (United States)

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

    2015-09-09

    Municipal tap water is increasingly treated at the point of use (POU) to improve the acceptability and palatability of its taste. The aim of this study was to assess the bacteriologic and nutritional characteristics of tap water treated at the point of use in residential healthcare facilities for the elderly. Two types of POU devices were used: microfiltered water dispensers (MWDs) and reverse-osmosis water dispensers (ROWDs). All samples of water entering the devices and leaving them were tested for the bacteriological parameters set by Italian regulations for drinking water and for opportunistic pathogens associated with various infections in healthcare settings; in addition, the degree of mineralization of the water was assessed. The results revealed widespread bacterial contamination in the POU treatment devices, particularly from potentially pathogenic species. As expected, the use of ROWDs led to a decrease in the saline content of the water. In conclusion, the use of POU treatment in healthcare facilities for the elderly can be considered advisable only if the devices are constantly and carefully maintained.

  2. Ability of treated kapok (Ceiba pentandra) fiber for removal of clay particle from water turbidity

    Science.gov (United States)

    Gafur, Nurfitri Abdul; Sakakibara, Masayuki; Jahja, Mohamad

    2017-06-01

    Kapok (Ceiba pentandra, family Bombacaceae) fiber (KF) is a by-product of traditional agriculture in tropical countries and is mainly used as fiberfill in fabric. The aim of this study was to explore the possibility of using KF to remove clay particles from turbid water. Firstly, KF was boiled at 100 ºC in deionized water for 15 min to remove the surface oil. A suspension of montmorillonite powder mixed 1 L of deionized water, divided into volumes of 100, 200, 300, and 400 mL, was used as the turbid water source. The ability of KF to remove clay particles from the water was assessed by filtering the water through 60 g of treated KF in a ∼397.9 cm3 acrylic column. Results showed that the treated KF effectively removed the clay particles from the entire volume of turbid water in this experiment; the results also demonstrate that this KF fiber has value as a simple and inexpensive tool for water treatment, especially in developing countries.

  3. The Physical, Chemical and Microbial Quality of Treated Water in Qom s Desalination Plants

    Directory of Open Access Journals (Sweden)

    A. R. Yari

    2007-04-01

    Full Text Available Background and objectivesWater is the basis of life and health. The health of food and water supply plays an important role in human health. One of the methods of water desalination is membrane filter reverse osmosis method. This method is used for desalination of drinking water supply in Qom.MethodsThis is a descriptive, cross-sectional study designed to determine the quality of treated water in Qom desalination plant in year 2002. Inlet and outlet water samples of this plant were examined by the standard examination methods and the collected data were compared with national and international standards. Excel software was used for statistical analysis.ResultsThe results showed that the residual chlorine concentration, total hardness and fluoride concentration were lower than the minimum standard limit set for drinking water. The pH was also lower than the minimum standard limit. Microbial contamination was detected in 6% of samples.ConclusionThe results show that the acidity of water was lower than standard in whole plant. This gives corrosive properties to the water and increases the dissolution of materials, which are in contact with this water. In order to eliminate the secondary contamination, the concentration of residual chlorine should be 1 mg/l. But, none of the measurements showed a concentration as high as this value. As fluoride is an important element for health and growth of bone and teeth, especially in growing children, fluoride should be added to the drinking water. As the relationship between hardness of water and cardiovascular diseases has been established, it can be concluded that this drinking water supply can increase the risk of cardiovascular diseases in long time. Dilution of this water is recommended to adjust various factors to the standard limits and keep the total dissolved solids low.Keywords: Qom ;Water; Reverse Osmosis; Desalination Plant; Water Quality

  4. Water quality changes in a post-herbicide treated water hyacinth ...

    African Journals Online (AJOL)

    Treatment in all cases significantly (P < 0.05) increased the mean alkalinity, pH, conductivity, organic matter, ionic and the solids contents of the water 28 days after treatment. Irrespective of herbicidal treatment, mortality of water hyacinth and subsequent decay in situ significantly lowered (P < 0.05) the amount of dissolved ...

  5. Apparatus and method for treating pollutants in a gas using hydrogen peroxide and UV light

    Science.gov (United States)

    Cooper, Charles David (Inventor); Clausen, Christian Anthony (Inventor)

    2005-01-01

    An apparatus for treating pollutants in a gas may include a source of hydrogen peroxide, and a treatment injector for creating and injecting dissociated hydrogen peroxide into the flow of gas. The treatment injector may further include an injector housing having an inlet, an outlet, and a hollow interior extending therebetween. The inlet may be connected in fluid communication with the source of hydrogen peroxide so that hydrogen peroxide flows through the hollow interior and toward the outlet. At least one ultraviolet (UV) lamp may be positioned within the hollow interior of the injector housing. The at least one UV lamp may dissociate the hydrogen peroxide flowing through the tube. The dissociated hydrogen peroxide may be injected into the flow of gas from the outlet for treating pollutants, such as nitrogen oxides.

  6. Microbial pathogens in source and treated waters from drinking water treatment plants in the United States and implications for human health

    Science.gov (United States)

    King, Dawn N.; Donohue, Maura J.; Vesper, Stephen J.; Villegas, Eric N.; Ware, Michael W.; Vogel, Megan E.; Furlong, Edward; Kolpin, Dana W.; Glassmeyer, Susan T.; Pfaller, Stacy

    2016-01-01

    An occurrence survey was conducted on selected pathogens in source and treated drinking water collected from 25 drinking water treatment plants (DWTPs) in the United States. Water samples were analyzed for the protozoa Giardia and Cryptosporidium (EPA Method 1623); the fungi Aspergillus fumigatus, Aspergillus niger and Aspergillus terreus (quantitative PCR [qPCR]); and the bacteria Legionella pneumophila (qPCR), Mycobacterium avium, M. avium subspecies paratuberculosis, and Mycobacterium intracellulare (qPCR and culture). Cryptosporidium and Giardia were detected in 25% and in 46% of the source water samples, respectively (treated waters were not tested). Aspergillus fumigatus was the most commonly detected fungus in source waters (48%) but none of the three fungi were detected in treated water. Legionella pneumophila was detected in 25% of the source water samples but in only 4% of treated water samples. M. avium and M. intracellulare were both detected in 25% of source water, while all three mycobacteria were detected in 36% of treated water samples. Five species of mycobacteria, Mycobacterium mucogenicum, Mycobacterium phocaicum, Mycobacterium triplex, Mycobacterium fortuitum, and Mycobacterium lentiflavum were cultured from treated water samples. Although these DWTPs represent a fraction of those in the U.S., the results suggest that many of these pathogens are widespread in source waters but that treatment is generally effective in reducing them to below detection limits. The one exception is the mycobacteria, which were commonly detected in treated water, even when not detected in source waters.

  7. Microbial pathogens in source and treated waters from drinking water treatment plants in the United States and implications for human health.

    Science.gov (United States)

    King, Dawn N; Donohue, Maura J; Vesper, Stephen J; Villegas, Eric N; Ware, Michael W; Vogel, Megan E; Furlong, Edward F; Kolpin, Dana W; Glassmeyer, Susan T; Pfaller, Stacy

    2016-08-15

    An occurrence survey was conducted on selected pathogens in source and treated drinking water collected from 25 drinking water treatment plants (DWTPs) in the United States. Water samples were analyzed for the protozoa Giardia and Cryptosporidium (EPA Method 1623); the fungi Aspergillus fumigatus, Aspergillus niger and Aspergillus terreus (quantitative PCR [qPCR]); and the bacteria Legionella pneumophila (qPCR), Mycobacterium avium, M. avium subspecies paratuberculosis, and Mycobacterium intracellulare (qPCR and culture). Cryptosporidium and Giardia were detected in 25% and in 46% of the source water samples, respectively (treated waters were not tested). Aspergillus fumigatus was the most commonly detected fungus in source waters (48%) but none of the three fungi were detected in treated water. Legionella pneumophila was detected in 25% of the source water samples but in only 4% of treated water samples. M. avium and M. intracellulare were both detected in 25% of source water, while all three mycobacteria were detected in 36% of treated water samples. Five species of mycobacteria, Mycobacterium mucogenicum, Mycobacterium phocaicum, Mycobacterium triplex, Mycobacterium fortuitum, and Mycobacterium lentiflavum were cultured from treated water samples. Although these DWTPs represent a fraction of those in the U.S., the results suggest that many of these pathogens are widespread in source waters but that treatment is generally effective in reducing them to below detection limits. The one exception is the mycobacteria, which were commonly detected in treated water, even when not detected in source waters. Published by Elsevier B.V.

  8. Development of infrared water sensors based on novel light sources

    Science.gov (United States)

    Donohue, John R.; Masterson, Hugh J.; Maze, Gwenael; O'Dwyer, Kieran; MacCraith, Brian D.

    2003-03-01

    The detection and measurement of vapour-phase or liquid-phase water is important in many industrial and chemical processes. Water exhibits strong absorption bands compared to other substances in the near infrared (NIR), and for this reason NIR spectroscopy is especially well suited to moisture determination. A lack of suitable sources in the NIR, however, has impeded the application of optical sensors to water detection. We have developed a modulatable IR source for use in a moisture sensor. In the system, the luminescent emission from optically pumped rare earth doped glasses is used. Thulium doped zirconium fluoride glass, which luminesces at 1.83 mm was the material chosen. The spectral overlap with the water absorption band is significant, and the output stability matches that of the pump source, which is typically an internally modulated diode laser emitting at 685nm. The detection system uses a reference beam and a probe beam to monitor changes in absorption due to moisture or water vapour. Results illustrating the effectiveness of the novel IR source in a sensor platform to measure trace amounts of liquid water and water vapor will be presented.

  9. Catalogue and classification of technical safety rules for light-water reactors and reprocessing plants

    International Nuclear Information System (INIS)

    Bloser, M.; Fichtner, N.; Neider, R.

    1975-08-01

    This report on the cataloguing and classification of technical rules for land-based light-water reactors and reprocessing plants contains a list of classified rules. The reasons for the classification system used are given and discussed

  10. Treated bottom ash medium and method of arsenic removal from drinking water

    Science.gov (United States)

    Gadgil, Ashok

    2009-06-09

    A method for low-cost arsenic removal from drinking water using chemically prepared bottom ash pre-treated with ferrous sulfate and then sodium hydroxide. Deposits on the surface of particles of bottom ash form of activated iron adsorbent with a high affinity for arsenic. In laboratory tests, a miniscule 5 grams of pre-treated bottom ash was sufficient to remove the arsenic from 2 liters of 2400 ppb (parts per billion) arsenic-laden water to a level below 50 ppb (the present United States Environmental Protection Agency limit). By increasing the amount of pre-treated bottom ash, even lower levels of post-treatment arsenic are expected. It is further expected that this invention supplies a very low-cost solution to arsenic poisoning for large population segments.

  11. Characterization samples of Tigris river water treated with nano colloidal silver (physically, chemically, microbiologically)

    International Nuclear Information System (INIS)

    Dumboos, H. I.; Beden, S. J.; Zouari, K.; Chkir, N.; Ahmed, H. A.

    2012-12-01

    Many researches of using nano silver in purification of drinking water from bacteria and its effect on stan dared properties as drinking water were established. Two stages accomplished in these projects. First stage include preparation of colloidal silver with characterization process and prepare water samples through sedimentation, filtration process, PH and turbidity measure then treated with colloidal silver in volume ratio (0.1-Λ) ml/100ml. The second stage represent select the better results from stage one and take samples to determine the standard characterization values with chemical, physical and microbiological taste. Results will be compared with Iraq standard certification. (Author)

  12. 10 CFR 50.46 - Acceptance criteria for emergency core cooling systems for light-water nuclear power reactors.

    Science.gov (United States)

    2010-01-01

    ... light-water nuclear power reactors. 50.46 Section 50.46 Energy NUCLEAR REGULATORY COMMISSION DOMESTIC... Approvals § 50.46 Acceptance criteria for emergency core cooling systems for light-water nuclear power reactors. (a)(1)(i) Each boiling or pressurized light-water nuclear power reactor fueled with uranium oxide...

  13. Position Of Light And Water In Architecture And Philosophy Of Art

    OpenAIRE

    Yurtyapan Salimi, Aysegul; Salimi, Amineddin; Kara Pilehvarian, Nuran

    2016-01-01

    Light and water re key elements and indicators are in human life. Water as a lifeblood is important in views, philosophies and cultures in the world and its role is considered beyond its functional role as a symbol of purity, birth and beauty. In ancient Persia, water was a sign of lighting and purity and was so valuable. Architects have always tried to make the best possible use of the environmental resources and water that was an important element to use all the beauty and perfe...

  14. 10-fold enhancement in light-driven water splitting using niobium oxynitride microcone array films

    KAUST Repository

    Shaheen, Basamat

    2016-03-26

    We demonstrate, for the first time, the synthesis of highly ordered niobium oxynitride microcones as an attractive class of materials for visible-light-driven water splitting. As revealed by the ultraviolet photoelectron spectroscopy (UPS), photoelectrochemical and transient photocurrent measurements, the microcones showed enhanced performance (~1000% compared to mesoporous niobium oxide) as photoanodes for water splitting with remarkable stability and visible light activity. © 2016 Elsevier B.V. All rights reserved.

  15. Recent advances of ultraviolet light technologies in water treatment

    Energy Technology Data Exchange (ETDEWEB)

    Traksel, D.; Vinnicombe, D.A.

    2001-05-01

    UV light is part of the electromagnetic spectrum, situated between X-rays and visible light, with a wavelength between 100 and 400 nm. The UV spectrum is split into a number of bands; each band is used in specific applications. UV-C and parts of UV-B band are used for disinfection purposes (between 200 and 315 nm). Vacuum UV is associated with the oxidation of organic carbon. UV disinfection technology has been around for a long time, but major advances have been made only in the last few decades. These advances include lamp manufacture technology with respect to output, wavelength spread and operating life, configuration design and monitoring. The use of specialized medium pressure lamps, as well as the combination of medium pressure and low pressure lamps has shown a number of advantages. (orig.)

  16. Seawater desalination using small and medium light water reactors

    Energy Technology Data Exchange (ETDEWEB)

    Shimamura, Kazuo [Mitsubishi Heavy Industries, Ltd., Yokohama, Kanagawa (Japan)

    2000-03-01

    Water is an essential substance for sustaining human life. As Japan is an island country, surrounded by the sea and having abundant rainfall, there is no scarcity of water in daily life except during abnormally dry summers or after disasters such as earthquakes. Consequently, there is hardly any demand for seawater desalination plants except on remote islands, Okinawa and a part of Kyushu. However, the IAEA has forecast a scarcity of drinking water in developing countries at the beginning of the 21st century. Further, much more irrigation water will be required every year to prevent cultivated areas from being lost by desertification. If developing countries were to produce such water by seawater desalination using current fossil fuel energy technology, it would cause increased air pollution and global warming. This paper explains the concept of seawater desalination plants using small and medium water reactors (hereinafter called 'nuclear desalination'), as well as important matters regarding the export nuclear desalination plants to developing countries. (author)

  17. Application of water-assisted ultraviolet light in combination of chlorine and hydrogen peroxide to inactivate Salmonella on fresh produce.

    Science.gov (United States)

    Guo, Shuanghuan; Huang, Runze; Chen, Haiqiang

    2017-09-18

    With the demand for fresh produce increases in recent decades, concerns for microbiological safety of fresh produce are also raised. To identify effective ultraviolet (UV) light treatment for fresh produce decontamination, we first determined the effect of three forms of UV treatment, dry UV (samples were treated by UV directly), wet UV (samples were dipped in water briefly and then exposed to UV), and water-assisted UV (samples were treated by UV while being immersed in agitated water) on inactivation of Salmonella inoculated on tomatoes and fresh-cut lettuce. In general, the water-assisted UV treatment was found to be the most effective for both produce items. Chlorine and hydrogen peroxide were then tested to determine whether they could be used to enhance the decontamination efficacy of water-assisted UV treatment and prevent transfer of Salmonella via wash water by completely eliminating it. Neither of them significantly enhanced water-assisted UV inactivation of Salmonella on tomatoes. Chlorine significantly improved the decontamination effectiveness of the water-assisted UV treatment for baby-cut carrots and lettuce, but not for spinach. In general, the single water-assisted UV treatment and the combined treatment of water-assisted UV and chlorine were similar or more effective than the chlorine washing treatment. In most of the cases, no Salmonella was detected in the wash water when the single water-assisted UV treatment was used to decontaminate tomatoes. In a few cases when Salmonella was detected in the wash water, the populations were very low,≤2CFU/mL, and the wash water contained an extremely high level of organic load and soil level. Therefore, the single water-assisted UV treatment could potentially be used as an environmentally friendly and non-chemical alternative to chlorine washing for tomatoes after validation in industrial scale. For lettuce, spinach and baby-cut carrots, the combined treatment of water-assisted UV treatment and chlorine

  18. The Physical, Chemical and Microbial Quality of Treated Water in Qom s Desalination Plants

    Directory of Open Access Journals (Sweden)

    A.R Yari

    2012-05-01

    Full Text Available

    Background and objectives

    Water is the basis of life and health. The health of food and water supply plays an important role in human health. One of the methods of water desalination is membrane filter reverse osmosis method. This method is used for desalination of drinking water supply in Qom.

    Methods

    This is a descriptive, cross-sectional study designed to determine the quality of treated water in Qom desalination plant in year 2002. Inlet and outlet water samples of this plant were examined by the standard examination methods and the collected data were compared with national and international standards. Excel software was used for statistical analysis.

    Results

    The results showed that the residual chlorine concentration, total hardness and fluoride concentration were lower than the minimum standard limit set for drinking water. The pH was also lower than the minimum standard limit. Microbial contamination was detected in 6% of samples.

    Conclusion

    The results show that the acidity of water was lower than standard in whole plant. This gives corrosive properties to the water and increases the dissolution of materials, which are in contact with this water. In order to eliminate the secondary contamination, the concentration of residual chlorine should be 1 mg/l. But, none of the measurements showed a concentration as high as this value. As fluoride is an important element for health and growth of bone and teeth, especially in growing children, fluoride should be added to the drinking water. As the relationship between hardness of water and cardiovascular diseases has been established, it can be concluded that this drinking water supply can increase the risk of cardiovascular diseases in long time. Dilution of this water is recommended to adjust various factors to the standard limits and keep the total dissolved solids low.

  19. Toxicity evaluation of surface water treated with different disinfectants in HepG2 cells.

    Science.gov (United States)

    Marabini, Laura; Frigerio, Silvia; Chiesara, Enzo; Radice, Sonia

    2006-01-01

    It is well known that water disinfection through chlorination causes the formation of a mixture of disinfection by-products (DBPs), many of which are genotoxic and carcinogenic. To demonstrate the formation of such compounds, a pilot water plant supplied with water from Lake Trasimeno was set up at the waterworks of Castiglione del Lago (PG, Italy). The disinfectants, continuously added to pre-filtered lake water flowing into three different basins, were sodium hypochlorite, chlorine dioxide and peracetic acid, an alternative disinfectant used until now for disinfecting waste waters, but not yet studied for a possible use in drinking water treatment. The aim of this study was to evaluate the formation during the disinfection processes of some toxic compounds that could explain the genotoxic effects of drinking waters. Differently treated waters were concentrated by solid-phase adsorption on silica C(18) columns and toxicity was assessed in a line of human hepatoma cells (HepG2), a metabolically competent cellular line very useful for human risk evaluation. The seasonal variability of the physical-chemical water characteristics (AOX, UV 254 nm, potential formation of THM, pH and temperature) made indispensable experimentation with water samples taken during the various seasons. Autumn waters cause greater toxicity compared to those of other seasons, in particular dilution of the concentrate at 0.5l equivalent of disinfected waters with chlorine dioxide and peracetic acid causes a 55% reduction in cellular vitality while the cellular vitality is over 80% with the all other water concentrates. Moreover it is very interesting underline that non-cytotoxic quantities of the autumnal water concentrates cause, after 2h treatment, a decrease in GSH and a statistically significant increase in oxygen radicals, while after prolonged treatment (24h) cause a GSH increase, without variations in the oxygen radical content. This phenomenon could be interpreted as the cellular

  20. REUSE OF TREATED WASTEWATER IN AGRICULTURE: SOLVING WATER DEFICIT PROBLEMS IN ARID AREAS (REVIEW

    Directory of Open Access Journals (Sweden)

    Faissal AZIZ

    2014-12-01

    Full Text Available In the arid and semiarid areas, the availability and the management of irrigation water have become priorities of great importance. The successive years of drought, induced by climate change and population growth, increasingly reduced the amount of water reserved for agriculture. Consequently, many countries have included wastewater reuse as an important dimension of water resources planning. In the more arid areas wastewater is used in agriculture, releasing high resource of water supplies. In this context, the present work is a review focusing the reuse of treated wastewater in agriculture as an important strategy for solving water deficit problems in arid areas. Much information concerning the wastewater reuse in different regions of the world and in Morocco, the different wastewater treatment technologies existing in Morocco were discussed. The review focused also the fertilizing potential of wastewater in agriculture, the role of nutrients and their concentrations in wastewater and their advantages effects on plant growth and yield.

  1. Comparison of in vitro estrogenic activity and estrogen concentrations in source and treated waters from 25 U.S. drinking water treatment plants

    Science.gov (United States)

    In vitro bioassays have been successfully used to screen for estrogenic activity in wastewater and surface water, however, few have been applied to treated drinking water. Here, extracts of source and treated drinking water samples were assayed for estrogenic activity using T47D...

  2. Potential Application of Nanomaterials to treat and detect the contaminated water

    Science.gov (United States)

    Singh, R. P.

    2011-12-01

    disinfectants to control water contamination and biofouling. To be developed items are as follows. Nanocatalysis (Au, Ag, Pd) approach to treat contaminated water, using desired form of nanocatalysts immobilized on a solid support. Nanostructured nanomaterials used, via filtration, adsorption to treat contaminated water. and To developed nanobiosensors to detect desired analytes of interest, and then bioremediation (use of microorganisms) and phytoremediation (use of plants) to treat contaminated water.

  3. The High-Altitude Water Cherenkov Observatory: First Light

    Science.gov (United States)

    Weisgarber, Thomas

    2013-04-01

    The High-Altitude Water Cherenkov (HAWC) Observatory is under construction at Sierra Negra in the state of Puebla in Mexico. Operation began in September 2012, with the first 30 out of the final 300 water Cherenkov detectors deployed and in data acquisition. The HAWC Observatory is designed to record particle air showers from gamma rays and cosmic rays with TeV energies. Though the detector is only 10% complete, HAWC is already the world's largest water Cherenkov detector in the TeV band. In this presentation, I will summarize the performance of the detector to date and discuss preliminary observations of cosmic-ray and gamma-ray sources. I will also describe deployment plans for the remainder of the detector and outline prospects for TeV observations in the coming year.

  4. Light water cooled, high temperature and high performance nuclear power plants concept of once-through coolant cycle, supercritical-pressure, light water cooled nuclear reactors

    Energy Technology Data Exchange (ETDEWEB)

    Oka, Yoshiaki; Koshizuka, Seiichi [Tokyo Univ.,Tokai Ibaraki (Japan). Nuclear Engineering Research Lab.

    2002-08-01

    Supercritical-pressure, light water cooled nuclear reactors corresponding to nuclear reactors of once-through boilers, are of theoretical development from LWR. Under supercritical pressure, a steam turbine can be driven directly with cooled water with high enthalpy, as not seen boiling and required for recycling. The reactor has no steam-water separation and recycling systems on comparison with the boiling water type LWR, and is the same once-through type as supercritical-pressure thermal power generation plants. Then, all of cooling water at reactor core are sent to turbine. The reactor has no steam generator, and pressurizer, on comparison with PWR. As it requires no steam-water separator, steam drier, and recycling system on comparison with BWR, it becomes of smaller size and has shape and size nearly equal to those of PWR. And, its control bars can be inserted from upper direction like PWR, and can use its driving system. Here was introduced some concepts on high-temperature and high-performance light water reactor, nuclear power generation using a technology on supercritical-pressure thermal power generation. (G.K.)

  5. Potential of domestic sewage effluent treated as a source of water and nutrients in hydroponic lettuce

    Directory of Open Access Journals (Sweden)

    Renata da Silva Cuba

    2015-07-01

    Full Text Available The search for alternative sources of water for agriculture makes the use of treated sewage sludge an important strategy for achieving sustainability. This study evaluated the feasibility of reusing treated sewage effluent as alternative source of water and nutrients for the hydroponic cultivation of lettuce (Lactuca sativa L. The experiment was conducted in the greenhouse of the Center for Agricultural Sciences - UFSCar, in Araras, SP. The cultivation took place from February to March 2014. The hydroponic system used was the Nutrient Film Technique, and included three treatments: 1 water supply and mineral fertilizers (TA; 2 use of effluent treated and complemented with mineral fertilizers based on results of previous chemical analysis (TRA; and 3 use of treated effluent (TR. The applied experimental design was four randomly distributed blocks. We evaluated the fresh weight, nutritional status, the microbiological quality of the culture, and the amount of mineral fertilizers used in the treatments. The fresh weights were subjected to analysis of variance and means were compared by the Tukey test at 5% probability. Only the TR treatment showed a significant difference in the evaluated variables, as symptoms of nutritional deficiencies in plants and significant reduction in fresh weights (p <0.01 were found. There was no detectable presence of Escherichia coli in any treatment, and it was possible to use less of some fertilizers in the TRA treatment compared to TA.

  6. Endotoxin concentration in treated water of all hemodialysis units in Greece and inquisition of influencing factors.

    Science.gov (United States)

    Arvanitidou, M; Spaia, S; Askepidis, N; Kanetidis, D; Pazarloglou, M; Katsouyannopoulos, V; Vayonas, G

    1999-01-01

    Mains and purified water samples from all hemodialysis centers in Greece were surveyed to assess hemodialysis water quality and the potential consequences on the dialysis population of any microbial and endotoxin contamination. Total heterotrophic bacteria counts were estimated employing the pour-plate method, the membrane filter technique, for total coliforms, fecal coliforms, enterococci and Pseudomonas spp., and the most probable number method for sulfite-reducing clostridia. Overall 170 paired samples were tested. Endotoxin concentrations were assayed in treated water samples, by the Limulus Amebocyte Lysate method, employing a chromogenic substrate. Endotoxin concentration varied from 0-30 EU/ml and exceeded 5 EU/ml in 30.6% of the centers. Endotoxin contaminated samples showed higher counts of total heterotrophic bacteria, fecal coliforms, enterococci and Pseudomonas spp. than the rest of the samples, though the difference was significant only for total heterotrophic bacteria and enterococci. Additionally, samples with endotoxin contamination derived from the mains water had significantly higher counts of fecal coliforms, enterococci and Pseudomonas spp. Endotoxin concentration was correlated with the presence of a deionization system, counts of fecal coliforms in supply water and counts of total coliforms, fecal coliforms and enterococci in treated water. These results demonstrate that hemodialysis centers in Greece need to monitor and preventively maintain the entire hemodialysis system, in order to ensure renal replacement therapy of good quality.

  7. Corrosion control when using passively treated abandoned mine drainage as alternative makeup water for cooling systems.

    Science.gov (United States)

    Hsieh, Ming-Kai; Chien, Shih-Hsiang; Li, Heng; Monnell, Jason D; Dzombak, David A; Vidic, Radisav D

    2011-09-01

    Passively treated abandoned mine drainage (AMD) is a promising alternative to fresh water as power plant cooling water system makeup water in mining regions where such water is abundant. Passive treatment and reuse of AMD can avoid the contamination of surface water caused by discharge of abandoned mine water, which typically is acidic and contains high concentrations of metals, especially iron. The purpose of this study was to evaluate the feasibility of reusing passively treated AMD in cooling systems with respect to corrosion control through laboratory experiments and pilot-scale field testing. The results showed that, with the addition of the inhibitor mixture orthophosphate and tolyltriazole, mild steel and copper corrosion rates were reduced to acceptable levels (< 0.127 mm/y and < 0.0076 mm/y, respectively). Aluminum had pitting corrosion problems in every condition tested, while cupronickel showed that, even in the absence of any inhibitor and in the presence of the biocide monochloramine, its corrosion rate was still very low (0.018 mm/y).

  8. Visible-light-induced water splitting on a chip

    NARCIS (Netherlands)

    Zoontjes, M.G.C.

    2015-01-01

    In this thesis, a photoelectrochemical water splitting cell concept is discussed, based on a combination of semiconductors comprising a Z-scheme. The motivation for the development of the cell is that in the future a transition will take place from a fossil fuel-based economy, to an economy based on

  9. Conclusions drawn of tritium balance in light water reactors

    International Nuclear Information System (INIS)

    Dolle, L.; Bazin, J.

    1978-01-01

    In the tritium balance of pressurized water reactors, using boric acid and lithium in the cooling water, contribution of the tritium produced by fission, diffusing through the zircalloy of the fuel cladding estimated to 0.1%, was not in agreement with quantities measured in reactors. It is still difficult to estimate what percentage is represented by the tritium formed by fission in the fuel, owing to diffusion through cladding. The tritium balance in different working nuclear power stations is consequently of interest. The tritium balance method in the water of the cooling circuit of PWR is fast and experimentally simple. It is less sensitive to errors originating from fission yields than balance of tritium produced by fission in the fuel. A tritium balance in the water of the cooling circuit of Biblis-A, with a specific burn-up of 18000 MWd/t gives a better precision. Diffusion rate of tritium produced by fission was less than 0.2%. So low a contribution is a justification to the use of lithium with an isotopic purity of 99.9% of lithium 7 to limit at a low value the residual lithium 6 [fr

  10. Study of the light emitted in the moderation of a heavy-water pile

    International Nuclear Information System (INIS)

    Breton, D.

    1958-06-01

    During the running of a reactor which uses water as a neutron moderator, a bluish light is seen to appear inside the liquid. A detailed study of this radiation, undertaken on the Fontenay-aux-Roses pile, has shown that the spectrum is identical with that which characterises the light produced by the Cerenkov effect. The light intensity as a function of the pile power grows exponentially as a function of time when the pile diverges, with a lifetime equal to that of the rise in power. An examination of the various particles present in the pile has led to the conclusion that only electrons with an energy greater than 260 keV con produce the Cerenkov light. The light source thus produced is about 2.10 6 photons/cm 2 of water, when the pile power equals 1 watt. (author) [fr

  11. Compressive strength measurements of hybrid dental composites treated with dry heat and light emitting diodes (LED post cure treatment

    Directory of Open Access Journals (Sweden)

    Jenny Krisnawaty

    2014-11-01

    Full Text Available Hybrid composites are mostly used on large cavities as restorative dental materials, whether it is used directly or indirectly. The mechanical properties of composite resin shall increase if it is treated with post cure treatment. The aim of this study is to evaluate compressive strength differences between dry heat and Light Emitting Diodes (LED treatment on the hybrid dental composite. A quasi-experimental was applied on this research with a total of 30 samples that were divided into two groups. Each sample was tested using LLOYD Universal Testing Machine with 1 mm/min speed to evaluate the compressive strength. The compressive strength results were marked when the sample was broken. The results of two groups were then analyzed using t-test statistical calculation. The results of this study show that post cure treatment on hybrid composite using LED light box (194.138 MPa was lower than dry heat treatment (227.339 MPa, which was also significantly different from statistical analysis. It can be concluded that compressive strength of LED light box was lower than dry heat post-cure treatment on the hybrid composite resin.

  12. EPA and USGS scientists conduct study to determine prevalence of newly-emerging contaminants in treated and untreated drinking water

    Science.gov (United States)

    Scientists from the EPA and USGS are collaborating on a research study to determine the presence of contaminants of emerging concern in treated and untreated drinking water collected from drinking water treatment plants.

  13. On phenomenon of light radiation from miniature balls immersed in water

    Energy Technology Data Exchange (ETDEWEB)

    Torchigin, V.P., E-mail: v_torchigin@mail.r [Institute of Informatics Problems, Russian Academy of Sciences, Nakhimovsky prospect 36/1, 119278, Moscow (Russian Federation); Torchigin, A.V. [Institute of Informatics Problems, Russian Academy of Sciences, Nakhimovsky prospect 36/1, 119278, Moscow (Russian Federation)

    2010-01-11

    A phenomenon of light radiation from miniature silicon balls produced at arc discharge and immersed in water is described. Video film showing shining balls in a vessel with water is presented. An explanation of this phenomenon is considered. Similarities and differences of this phenomenon with a phenomenon of ball lightning are analyzed.

  14. On phenomenon of light radiation from miniature balls immersed in water

    Science.gov (United States)

    Torchigin, V. P.; Torchigin, A. V.

    2010-01-01

    A phenomenon of light radiation from miniature silicon balls produced at arc discharge and immersed in water is described. Video film showing shining balls in a vessel with water is presented. An explanation of this phenomenon is considered. Similarities and differences of this phenomenon with a phenomenon of ball lightning are analyzed.

  15. Electrophoretic mobility of PM2 DNA treated with ultimate chemical carcinogens or with ultraviolet light

    International Nuclear Information System (INIS)

    Thielmann, H.W.; Hecht, R.

    1980-01-01

    Superhelical DNA of the Pseudomonas phage PM2 was irradiated with UV-light or reacted with covalently binding carcinogens, such as 7-bromomethyl-benz[a]anthracene, (Ac) 2 ONFln, K-region epoxides, and alkylating agents. Migration velocity of the DNA products was determined using agarose gel electrophoresis. In gels of more than 1.3%-1.9% agarose, modified PM2 DNA exhibited a dose-(concentration-)dependent decrease of migration velocity. This phenomenon is probably due to a decrease in superhelix density which caused the compact DNA coil to assume eventually an open-circular conformation. Comparison of the extent of DNA modification with the decrease of migration velocity revealed that the superhelical structure sensitively reflected the chemical DNA alterations. DNA species exhibiting in 1.6% agarose gels, a migration velocity of up to 30% of that of control DNA showed an increase of velocity in 0.4% agarose. Therefore, in 1.3%-1.9% agarose gels, the decrease of superhelix density is accompanied by an increase of the frictional coefficient, whereas in 0.4%-0.9% agarose gels the same decrease of superhelix density apparently led to a higher degree of flexibility of the macromolecule and/or exposure of additional electric charges. (orig.) [de

  16. Light and electron microscopic analysis of tattoos treated by Q-switched ruby laser

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, C.R.; Anderson, R.R.; Gange, R.W.; Michaud, N.A.; Flotte, T.J. (Massachusetts General Hospital, Boston (USA))

    1991-07-01

    Short-pulse laser exposures can be used to alter pigmented structures in tissue by selective photothermolysis. Potential mechanisms of human tattoo pigment lightening with Q-switched ruby laser were explored by light and electron microscopy. Significant variation existed between and within tattoos. Electron microscopy of untreated tattoos revealed membrane-bound pigment granules, predominantly within fibroblasts and macrophages, and occasionally in mast cells. These granules contained pigment particles ranging from 2-in diameter. Immediately after exposure, dose-related injury was observed in cells containing pigment. Some pigment particles were smaller and lamellated. At fluences greater than or equal to 3 J/cm2, dermal vacuoles and homogenization of collagen bundles immediately adjacent to extracellular pigment were occasionally observed. A brisk neutrophilic infiltrate was apparent by 24 h. Eleven days later, the pigment was again intracellular. Half of the biopsies at 150 d revealed a mild persistent lymphocytic infiltrate. There was no fibrosis except for one case of clinical scarring. These findings confirm that short-pulse radiation can be used to selectively disrupt cells containing tattoo pigments. The physial alteration of pigment granules, redistribution, and elimination appear to account for clinical lightening of the tattoos.

  17. Petal abscission in rose flowers: effects of water potential, light intensity and light quality

    NARCIS (Netherlands)

    Doorn, van W.G.; Vojinovic, A.

    1996-01-01

    Petal abscission was studied in roses (Rosa hybrida L.), cvs. Korflapei (trade name Frisco), Sweet Promise (Sonia) and Cara Mia (trade name as officially registered cultivar name). Unlike flowers on plants in greenhouses, cut flowers placed in water in the greenhouse produced visible symptoms of

  18. Suitability of Using Duckweed as Feed and Treated Sewage as Water Source in Tilapia Aquaculture

    International Nuclear Information System (INIS)

    EI-Shafail, S.A.; Nasrl, F.A.; EI-Gohary, F.A. A.; Cijzen, H.J.; Steen, N.P.

    2004-01-01

    Use of treated effluent and duckweed biomass from a pilot-scale UASB-duckweed ponds system treating domestic sewage was evaluated in rearing Nile tilapia (Oreochromis niloticus). Nutritional value of duckweed as sole feed was compared with wheat bran. Two sources of water were used for each feed trial, treated-sewage and freshwater. The experiment was conducted in parallel with a conventional settled sewage-fed fishpond. Results of growth performance demonstrated that, in case of freshwater ponds specific growth rate (SGR) of tilapia fed on fresh duckweed was significantly (p 0.05) was observed between the two feeding regimes in treated sewage fed ponds. The SGR of tilapia reared in the treated sewage-wheat bran-fed pond (TWP) was significant higher (p <0.01) than the SGR in the freshwater-wheat bran-fed pond (FWP). On the other hand, due to the early spawning in the treated sewage-duckweed fed pond (TOP) SGR of tilapia in the latter was significantly lower (p <0.05) than the SGR in the freshwater-duckweed-fed pond (FDP). The results of net fish yield were 11.8, 8.9, 9.6 and 6.4 ton/ha/y in TDP, TWP, FDP and FWP, respectively. negative net yield (-0.16 ton/ha/y) was observed in the settled sewage- fed pond (SSP) due to high mortality

  19. Electron beam induced dis-infection of biologically treated waste water effluent

    International Nuclear Information System (INIS)

    Rawat, K.P.; Khader, S.A.; Sarma, K.S.S.

    2012-01-01

    The conservation of water is need of the hour as there is vast gap between demand and supply. The waste water generated in conventional waste water treatment plant can be recycled for irrigation. The presence of pathogenic micro-organism makes it unsafe for this purpose. EB is very effective in killing all forms of pathogens. The biologically treated waste water effluent was used for this purpose. The pathogen count reduced to undetectable level with the EB dose of 0.45 kGy. The BOD and COD values were within the permissible limit. The other physico-chemical parameters remained unaltered. The ability of EB to deliver higher dose rates makes it ideal for handling large volumes of effluent generated in megacities. (author)

  20. Low turn-on voltage perovskite light-emitting diodes with methanol treated PEDOT:PSS as hole transport layer

    Science.gov (United States)

    Wang, Zijun; Li, Zhirun; Zhou, Dianli; Yu, Junsheng

    2017-12-01

    We demonstrate the reduced low turn-on voltage of perovskite light-emitting diodes (PeLEDs) with methanol (MeOH) treated poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) as a hole transport layer (HTL). The MeOH treated PEDOT:PSS layer presents improved hole injection through reducing the contact barrier between the HTL and the CH3NH3PbBr3 emitting layer without sacrificing the quality of the perovskite film, which was characterized by X-ray diffraction, scanning electron microscopy, and time-resolved photoluminescence analysis. The optimized PeLEDs with the MeOH treated PEDOT:PSS layer exhibit a low turn-on voltage of 2.4 V and a maximum luminance of 1565 cd/m2, which represents a significant improvement over the PeLEDs using a pristine PEDOT:PSS layer. The approach could be used as a general method for decreasing the hole-injection barrier of PeLEDs and, eventually, to enhance the device performance.

  1. Treating metabolic syndrome's metaflammation with low level light therapy: preliminary results

    Science.gov (United States)

    Yoshimura, Tania M.; Kato, Ilka T.; Deana, Alessandro M.; Ribeiro, Martha S.

    2014-02-01

    Metabolic syndrome comprises a constellation of morbidities such as insulin resistance, hyperinsulinemia, atherogenic dyslipidemia, dysglycemia and obesity (especially abdominal). Metabolic alterations are observed in major insulin target organs, increasing the risk of cardiovascular diseases, type-2 diabetes and therefore mortality. Tissue alterations are characterized by immune cells infiltrates (especially activated macrophages). Released inflammatory mediators such as TNF-α induce chronic inflammation in subjects with metabolic syndrome, since inflammatory pathways are activated in the neighboring cells. The intra-abdominal adipose tissue appears to be of particular importance in the onset of the inflammatory state, and strategies contributing to modulate the inflammatory process within this adipose tissue can mitigate the metabolic syndrome consequences. Considering the low level light therapy (LLLT) recognized benefits in inflammatory conditions, we hypothesized this therapeutic approach could promote positive effects in modulating the inflammatory state of metabolic syndrome. That being the scope of this study, male C57BL/6 mice were submitted to a high-fat/high-fructose diet among 8 weeks to induce metabolic syndrome. Animals were then irradiated on the abdominal region during 21 days using an 850 nm LED (6 sessions, 300 seconds per session, 60 mW output power, ~6 J/cm2 fluence, ~19 mW/cm2 fluence rate). Before and during treatment, blood was sampled either from the retroorbital plexus or from tail puncture for glucose, total cholesterol and triglycerides analysis. So far our results indicate no alterations on these metabolic parameters after LLLT. For further investigations, blood was collected for plasma inflammatory cytokine quantification and fresh ex vivo samples of liver and intra-abdominal adipose tissue were harvested for immunohistochemistry purposes.

  2. DNA repair and induction of plasminogen activator in human fetal cells treated with ultraviolet light

    International Nuclear Information System (INIS)

    Ben-Ishai, R.; Sharon, R.; Rothman, M.; Miskin, R.

    1984-01-01

    We have tested human fetal fibroblasts for development associated changes in DNA repair by utilizing nucleoid sedimentation as an assay for excision repair. Among skin fibroblasts the rate of excision repair was significantly higher in non-fetal cells than in fibroblasts derived from an 8 week fetus; this was evident by a delay in both the relaxation and the restoration of DNA supercoiling in nucleoids after irradiation. Skin fibroblasts derived at 12 week gestation were more repair proficient than those derived at 8 week gestation. However, they exhibited a somewhat lower rate of repair than non-fetal cells. The same fetal and non-fetal cells were also tested for induction of the protease plasminogen activator (PA) after u.v. irradiation. Enhancement of PA was higher in skin fibroblasts derived at 8 week than in those derived at 12 week gestation and was absent in non-fetal skin fibroblasts. These results are consistent with our previous findings that in human cells u.v. light-induced PA synthesis is correlated with reduced DNA repair capacity. Excision repair and PA inducibility were found to depend on tissue of origin in addition to gestational stage, as shown for skin and lung fibroblasts from the same 12 week fetus. Lung compared to skin fibroblasts exhibited lower repair rates and produced higher levels of PA after irradiation. The sedimentation velocity of nucleoids, prepared from unirradiated fibroblasts, in neutral sucrose gradients with or without ethidium bromide, indicated the presence of DNA strand breaks in fetal cells. It is proposed that reduced DNA repair in fetal cells may result from alterations in DNA supercoiling, and that persistent DNA strand breaks enhance transcription of PA gene(s)

  3. Design and Fluid Dynamic Investigations for a High Performance Light Water Reactor Fuel Assembly

    Science.gov (United States)

    Hofmeister, Jan; Laurin, Eckart; Class, Andreas G.

    2005-11-01

    Within the 5th Framework Program of the European Commission a nuclear light water reactor with supercritical steam conditions has been investigated called High Performance Light Water Reactor (HPLWR). This reactor concept is distinct from conventional light water reactor concepts by the fact, that supercritical water is used to achieve higher core outlet temperatures. The reactor operates with a high system pressure, high heat-up of the coolant within the core, and high outlet temperatures of the coolant resulting in a thermal efficiency of up to 44%. We present the design concept proposed by IKET, and a fluid dynamic problem in the foot piece of the fuel assembly, where unacceptable temperature variations must be omitted.

  4. Effect of water chemistry improvement on flow accelerated corrosion in light-water nuclear reactor

    International Nuclear Information System (INIS)

    Sugino, Wataru; Ohira, Taku; Nagata, Nobuaki; Abe, Ayumi; Takiguchi, Hideki

    2009-01-01

    Flow Accelerated Corrosion (FAC) of Carbon Steel (CS) piping has been one of main issues in Light-Water Nuclear Reactor (LWRs). Wall thinning of CS piping due to FAC increases potential risk of pipe rupture and cost for inspection and replacement of damaged pipes. In particular, corrosion products generated by FAC of CS piping brought steam generator (SG) tube corrosion and degradation of thermal performance, when it intruded and accumulated in secondary side of PWR. To preserve SG integrity by suppressing the corrosion of CS, High-AVT chemistry (Feedwater pH9.8±0.2) has been adopted to Tsuruga-2 (1160 MWe PWR, commercial operation in 1987) in July 2005 instead of conventional Low-AVT chemistry (Feedwater pH 9.3). By the High-AVT adoption, the accumulation rate of iron in SG was reduced to one-quarter of that under conventional Low-AVT. As a result, a tendency to degradation of the SG thermal efficiency was improved. On the other hand, it was clarified that High-AVT is ineffective against Flow Accelerated Corrosion (FAC) at the region where the flow turbulence is much larger. By contrast, wall thinning of CS feed water pipes due to FAC has been successfully controlled by oxygen treatment (OT) for long time in BWRs. Because Magnetite film formed on CS surface under AVT chemistry has higher solubility and porosity in comparison with Hematite film, which is formed under OT. In this paper, behavior of the FAC under various pH and dissolved oxygen concentration are discussed based on the actual wall thinning rate of BWR and PWR plant and experimental results by FAC test-loop. And, it is clarified that the FAC is suppressed even under extremely low DO concentration such as 2ppb under AVT condition in PWR. Based on this result, we propose the oxygenated water chemistry (OWC) for PWR secondary system which can mitigate the FAC of CS piping without any adverse effect for the SG integrity. Furthermore, the applicability and effectiveness of this concept developed for FAC

  5. Highly treated mine waters may require major ion addition before environmental release.

    Science.gov (United States)

    Harford, Andrew J; Jones, David R; van Dam, Rick A

    2013-01-15

    Mining operations often use passive and/or active water treatments to improve water quality prior to environmental release. Key considerations in choosing a treatment process include the extent to which the water quality is actually improved, and the potential residual environmental risks of the release of such water. However, there are few published studies concerning the environmental impacts of treated waste waters. This study used toxicity identification evaluation (TIE) methods to quantify and identify the "toxic" constituents of a highly-treated water (distillate) produced by brine concentration of a mining process water. Exposure of five freshwater species (Chlorella sp., Lemna aequinoctialis, Hydra viridissima, Moinodaphnia macleayi and Mogurnda mogurnda) to a concentration range of the distillate (0, 25, 50 and 100%) found that it was toxic to H. viridissima (50-100% effect when exposed to 100% distillate). TIE tests demonstrated that the effect wasn't due to residual ammonia (~1 mg L(-1)N) or trace organics, and unlikely to be due to manganese (Mn; 130-230 μg L(-1)). Conversely, addition of 0.2 and 0.5 mg L(-1) calcium improved the growth rate of H. viridissima by 61 and 66%, respectively, while addition of calcium, sodium and potassium (0.5, 1.0 and 0.4 mg L(-1), respectively) to levels comparable to that in the local aquatic environment resulted in 100% recovery. Further assessment on the likelihood of residual metal toxicity indicated that Mn concentrations in the distillate were at levels that could inhibit the growth of H. viridissima. Ultimately, the results demonstrated that ion deficiency should be considered as a potential stressor in risk/impact assessments of the discharge of treated wastewaters, and these may need to be supplemented with the deficient ions to reduce environmental impacts. The findings have highlighted the need for water managers to consider the possibility of unintended environmental risks from the discharge of highly-treated

  6. Deposition of LDH on plasma treated polylactic acid to reduce water permeability

    KAUST Repository

    Bugatti, Valeria

    2013-04-01

    A simple and scalable deposition process was developed to prepare polylactic acid (PLA) coatings with enhanced water barrier properties for food packaging applications. This method based on electrostatic interactions between the positively charged layers of layered double hydroxides (LDHs) modified with ionic liquids (ILs) and the negatively charged plasma treated polylactic acid leads to homogeneous, stable, and highly durable coatings. Deposition of the LDH coatings increases the surface hydrophobicity of the neat PLA, which results to a decrease in water permeability by about 35%. © 2013 Elsevier Inc.

  7. Method and equipment for treating waste water resulting from the technological testing processes of NPP equipment

    International Nuclear Information System (INIS)

    Radulescu, M. C.; Valeca, S.; Iorga, C.

    2016-01-01

    Modern methods and technologies coupled together with advanced equipment for treating residual substances resulted from technological processes are mandatory measures for all industrial facilities. The correct management of the used working agents and of the all wastes resulted from the different technological process (preparation, use, collection, neutralization, discharge) is intended to reduce up to removal of their potential negative impact on the environment. The high pressure and temperature testing stands from INR intended for functional testing of nuclear components (fuel bundles, fuelling machines, etc.) were included in these measures since the use of oils, demineralized water chemically treated, greases, etc. This paper is focused on the method and equipment used at INR Pitesti in the chemical treatment of demineralized waters, as well as the equipment for collecting, neutralizing and discharging them after use. (authors)

  8. Bioassay using the water soluble fraction of a Nigerian Light Crude ...

    African Journals Online (AJOL)

    Summary: A 96-hour bioassay was conducted using the water soluble fraction of a Nigerian light crude oil sample on Clarias gariepinus fingerlings. 0, 2.5, 5.0, 7.5 and 10 mls of water soluble fractions (WSF) of the oil were added to 1000 litres of de-chlorinated tap water to form 0, 25, 50 , 75 and 100 parts per million ...

  9. New model for counter-current flow during reflood in light water reactors

    International Nuclear Information System (INIS)

    Carbajo, J.J.

    1984-01-01

    Counter-current flow (CCF) of steam and water may occur at the upper core plate of a light water reactor (LWR) under reflood conditions. This paper describes a new model for CCF and flooding at the upper core plate of a LWR. The model assumes separate paths for the water draining through some open area of the upper core plate and the steam rising up through the remaining open area. Condensation of steam is not considered

  10. Evaluation of Subsurface Flow and Free-water Surface Wetlands Treating NPR-3 Produced Water - Year No. 1

    Energy Technology Data Exchange (ETDEWEB)

    Myers, J. E.; Jackson, L. M.

    2001-10-13

    This paper is a summary of some of the activities conducted during the first year of a three-year cooperative research and development agreement (CRADA) between the Department of Energy (DOE) Rocky Mountain Oilfield Testing Center (RMOTC) and Texaco relating to the treatment of produced water by constructed wetlands. The first year of the CRADA is for design, construction and acclimation of the wetland pilot units. The second and third years of the CRADA are for tracking performance of pilot wetlands as the plant and microbial communities mature. A treatment wetland is a proven technology for the secondary and tertiary treatment of produced water, storm water and other wastewaters. Treatment wetlands are typically classified as either free-water surface (FWS) or subsurface flow (SSF). Both FWS and SSF wetlands work well when properly designed and operated. This paper presents a collection of kinetic data gathered from pilot units fed a slipstream of Wyoming (NPR-3) produced water. The pilot units are set up outdoors to test climatic influences on treatment. Monitoring parameters include evapotranspiration, plant growth, temperature, and NPDES discharge limits. The pilot wetlands (FWS and SSF) consist of a series of 100-gal plastic tubs filled with local soils, gravel, sharp sand and native wetland plants (cattail (Typha spp.), bulrush (Scirpus spp.), dwarf spikerush (Eleocharis)). Feed pumps control hydraulic retention time (HRT) and simple water control structures control the depth of water. The treated water is returned to the existing produced water treatment system. All NPDES discharge limits are met. Observations are included on training RMOTC summer students to do environmental work.

  11. Characterization of 14C in Swedish light water reactors.

    Science.gov (United States)

    Magnusson, Asa; Aronsson, Per-Olof; Lundgren, Klas; Stenström, Kristina

    2008-08-01

    This paper presents the results of a 4-y investigation of 14C in different waste streams of both boiling water reactors (BWRs) and pressurized water reactors (PWRs). Due to the potential impact of 14C on human health, minimizing waste and releases from the nuclear power industry is of considerable interest. The experimental data and conclusions may be implemented to select appropriate waste management strategies and practices at reactor units and disposal facilities. Organic and inorganic 14C in spent ion exchange resins, process water systems, ejector off-gas and replaced steam generator tubes were analyzed using a recently developed extraction method. Separate analysis of the chemical species is of importance in order to model and predict the fate of 14C within process systems as well as in dose calculations for disposal facilities. By combining the results of this investigation with newly calculated production rates, mass balance assessments were made of the 14C originating from production in the coolant. Of the 14C formed in the coolant of BWRs, 0.6-0.8% was found to be accumulated in the ion exchange resins (core-specific production rate in the coolant of a 2,500 MWth BWR calculated to be 580 GBq GW(e)(-1) y(-1)). The corresponding value for PWRs was 6-10% (production rate in a 2,775 MWth PWR calculated to be 350 GBq GW(e)(-1) y(-1)). The 14C released with liquid discharges was found to be insignificant, constituting less than 0.5% of the production in the coolant. The stack releases, routinely measured at the power plants, were found to correspond to 60-155% of the calculated coolant production, with large variations between the BWR units.

  12. The morphological changes of Ascaris lumbricoides ova in sewage sludge water treated by gamma irradiation

    Science.gov (United States)

    Shamma, M.; Al-Adawi, M. A.

    2002-10-01

    Untreated wastewater sampled from Damascus sewage water treatment plant containing nematode Ascaris lumbricoides ova were treated using gamma irradiation (doses between 1.5 and 8 kGy), immediately after irradiation the morphological and developmental status of eggs was examined microscopically. Major morphological changes of the contents of the eggs were detected. These eggs were incubated for 8 weeks, after this period no larvae "inside the eggs" were observed. Thus the morphological changes can be used as a viable parameter.

  13. EFFECTIVENESS OF CHITOSAN AS NATURAL COAGULANT AID IN TREATING TURBID WATERS

    OpenAIRE

    B. Bina ، M. H. Mehdinejad ، M. Nikaeen ، H. Movahedian Attar

    2009-01-01

    During the last decade, there has been a concern about the relation between aluminum residuals in treated water and Alzheimer disease, and more interest has been considered on the development of natural coagulants such as chitosan. Chitosan, a natural linear biopolyaminosaccharide, is obtained by alkaline deacetylation of chitin. The present study was aimed to investigate the effects of alum as coagulant in conjunction with chitosan as coagulant aid on the removal of turbidity, hardness and E...

  14. Volatile organic compounds in natural biofilm in polyethylene pipes supplied with lake water and treated water from the distribution network.

    Science.gov (United States)

    Skjevrak, Ingun; Lund, Vidar; Ormerod, Kari; Herikstad, Hallgeir

    2005-10-01

    The objective of this work was investigation of volatile organic compounds (VOC) in natural biofilm inside polyethylene (HDPE) pipelines at continuously flowing water. VOC in biofilm may contribute to off-flavour episodes in drinking water. The pipelines were supplied with raw lake water and treated water from the distribution network. Biofilm was established at test sites located at two different drinking water distribution networks and their raw water sources. A whole range of volatile compounds were identified in the biofilm, including compounds frequently associated with cyanobacteria and algae, such as ectocarpene, dictyopterene A and C', geosmin, beta-ionone and 6-methyl-5-hepten-2-one. In addition, volatile amines, dimethyldisulphide and 2-nonanone, presumably originating from microorganisms growing in the biofilm, were identified. C8-compounds such as 1-octen-3-one and 3-octanone were believed to be products from microfungi in the biofilm. Degradation products from antioxidants such as Irgafos 168, Irganox 1010 and Irganox 1076 used in HDPE pipes, corresponding to 2,4-di-tert-butylphenol and 2,6-di-tert-butylbenzoquinone, were present in the biofilm.

  15. Emergency action levels for light water reactors. Draft report

    International Nuclear Information System (INIS)

    1981-10-01

    United States nuclear power plants are currently preparing revised radiological emergency response plans. As part of these plans, each licensee is establishing plant-specific instrumentation readings, called emergency action levels (EALs), that indicate the presence of a problem and the need to declare one of four classes of emergency as designated by the U.S. Nuclear Regulatory Commission. In this report, the EALs prepared for a pressurized water reactor and a boiling water reactor are assessed to determine whether they meet the requirements of NUREG-0654, Rev. 1 Appendix 1. In addition, five recent nuclear incidents are studied to determine how their outcomes might have been affected by the new emergency response plans. Most of the EALs reviewed were judged adequate. In some cases, alternate EALs or sets of generic EALs are proposed to meet the intent of NUREG-0654 Rev 1 Appendix 1, and the wording of some of the initiating conditions for the four emergency classes is clarified. For three of the five incidents reviewed, the new emergency response plans probably would not have affected the outcome; in one case, the plans would probably have prevented core damage; and any effect on the outcome of the last incident is uncertain

  16. Experimental studies on catalytic hydrogen recombiners for light water reactors

    International Nuclear Information System (INIS)

    Drinovac, P.

    2006-01-01

    In the course of core melt accidents in nuclear power plants a large amount of hydrogen can be produced and form an explosive or even detonative gas mixture with aerial oxygen in the reactor building. In the containment atmosphere of pressurized water reactors hydrogen combines a phlogistically with the oxygen present to form water vapor even at room temperature. In the past, experimental work conducted at various facilities has contributed little or nothing to an understanding of the operating principles of catalytic recombiners. Hence, the purpose of the present study was to conduct detailed investigations on a section of a recombiner essentially in order to deepen the understanding of reaction kinetics and heat transport processes. The results of the experiments presented in this dissertation form a large data base of measurements which provides an insight into the processes taking place in recombiners. The reaction-kinetic interpretation of the measured data confirms and deepens the diffusion theory - proposed in an earlier study. Thus it is now possible to validate detailed numeric models representing the processes in recombiners. Consequently the present study serves to broaden and corroborate competence in this significant area of reactor technology. In addition, the empirical knowledge thus gained may be used for a critical reassessment of previous numeric model calculations. (orig.)

  17. Toxicity of treated bilge water: The need for revised regulatory control.

    Science.gov (United States)

    Tiselius, Peter; Magnusson, Kerstin

    2017-01-30

    Water accumulating in the bottom of ships (bilge water), contains a mixture of oil, detergents and other compounds from on board activities. To evaluate ecological effects of released bilge water the chemical composition and toxicity of treated bilge water from seven passenger ships was analysed. The oil content was below 15mgL -1 , the threshold for legal discharge, in all but one ship. Still, significant reductions in feeding and reproduction of Acartia tonsa were found after 48h exposure in dilutions with 2.5-5% of bilge water. Mortality was significant at dilutions of 5-10% in 4 of the 5 bilge water samples. Surfactants were the most significant contributor to the toxicity on copepod vital rates and survival. Toxicity was also tested with Microtox where an EC 50 was found at dilutions between 4.3% and 52%. The results show that ecological effects might occur also in diluted suspensions of bilge water. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Impact of different moderator ratios with light and heavy water cooled reactors in equilibrium states

    International Nuclear Information System (INIS)

    Permana, Sidik; Takaki, Naoyuki; Sekimoto, Hiroshi

    2006-01-01

    As an issue of sustainable development in the world, energy sustainability using nuclear energy may be possible using several different ways such as increasing breeding capability of the reactors and optimizing the fuel utilization using spent fuel after reprocessing as well as exploring additional nuclear resources from sea water. In this present study the characteristics of light and heavy water cooled reactors for different moderator ratios in equilibrium states have been investigated. The moderator to fuel ratio (MFR) is varied from 0.1 to 4.0. Four fuel cycle schemes are evaluated in order to investigate the effect of heavy metal (HM) recycling. A calculation method for determining the required uranium enrichment for criticality of the systems has been developed by coupling the equilibrium fuel cycle burn-up calculation and cell calculation of SRAC 2000 code using nuclear data library from the JENDL 3.2. The results show a thermal spectrum peak appears for light water coolant and no thermal peak for heavy water coolant along the MFR (0.1 ≤ MFR ≤ 4.0). The plutonium quality can be reduced effectively by increasing the MFR and number of recycled HM. Considering the effect of increasing number of recycled HM; it is also effective to reduce the uranium utilization and to increase the conversion ratio. trans-Plutonium production such as americium (Am) and curium (Cm) productions are smaller for heavy water coolant than light water coolant. The light water coolant shows the feasibility of breeding when HM is recycled with reducing the MFR. Wider feasible area of breeding has been obtained when light water coolant is replaced by heavy water coolant

  19. Investigation of Water Safety in Non-treated Drinking Water with Trace Toxic Metals.

    Science.gov (United States)

    Ly, Suw Young; Kim, Dae Hong; Lee, Ga Eun

    2013-09-01

    The trace toxic metal copper was assayed using mercury immobilized on a carbon nanotube electrode (MCW), with a graphite counter and a reference electrode. In this study, a macro-scale convection motor was interfaced with a MCW three-electrode system, in which a handmade MCW was optimized using cyclic- and square-wave stripping voltammetry. An analytical electrolyte for tap water was used instead of an expensive acid or base ionic solution. Under these conditions, optimum parameters were 0.09 V amplitude, 40 Hz frequency, 0.01 V incremental potential, and a 60-s accumulation time. A diagnostic working curve was obtained from 50.0 to 350 μg/L. At a constant Cu(II) concentration of 10.0 μg/L, the statistical relative standard deviation was 1.78% (RSD, n = 15), the analytical accumulation time was only 60 s, and the analytical detection limit approached 4.6 μg/L (signal/noise = 3). The results were applied to nontreated drinking water. The content of the analyzed copper using 9.0 and 4.0 μg/L standards were 8.68 μg/L and 3.96 μg/L; statistical values R(2) = 0.9987 and R(2) = 0.9534, respectively. This method is applicable to biological diagnostics or food surveys.

  20. Biomechanical evidence of the distribution of cross-links in corneas treated with riboflavin and ultraviolet A light.

    Science.gov (United States)

    Kohlhaas, Markus; Spoerl, Eberhard; Schilde, Thomas; Unger, Gabriele; Wittig, Christine; Pillunat, Lutz E

    2006-02-01

    To examine to which depth of the cornea the stiffening effect is biomechanically detectable. Department of Ophthalmology, University of Dresden, Dresden, Germany. Of 40 enucleated porcine eyes, 20 eyes were treated with the photosensitizer riboflavin (0.1%) and ultraviolet A (UVA) light (370 nm, 3 mW/cm2, 30 minutes); the other 20 eyes served as control. From each eye, 2 flaps of 200 microm thickness were cut with a microkeratome, and strips of 5 mm width and 7 mm length were prepared. Stress-strain behavior was measured with a material tester to characterize the stiffening effect. Five pairs of human donor eyes were tested in the same way. In porcine corneas, the stiffening effect was stronger in the anterior-treated flaps than in the posterior-treated flaps and the control flaps (P = .001). A 5% strain was achieved at a stress of 261.7 +/- 133.2 x 10(3) N/m2 in the anterior-treated flaps and 104.1 +/- 52.7 x 10(3) N/m2 in the anterior control flaps. The posterior-treated flaps (105.0 +/- 55.8 x 10(3) N/m2) and the posterior control flaps (103.7 +/- 61.8 x 10(3) N/m2) showed no difference (P = .95). A similar stiffening effect was observed in human eyes, but contrary to findings in porcine corneas, in human corneas the anterior control flaps were stiffer than the posterior control flaps (P = .027). Treatment of the cornea with riboflavin and UVA significantly stiffened the cornea only in the anterior 200 microm. This depth-dependent stiffening effect may be explained by the absorption behavior for UVA in the riboflavin-treated cornea. Sixty-five percent to 70% of UVA irradiation was absorbed within the anterior 200 microm and only 20% in the next 200 microm. Therefore, deeper structures and even the endothelium are not affected.

  1. Analysis of alternative light water reactor (LWR) fuel cycles

    International Nuclear Information System (INIS)

    Heeb, C.M.; Aaberg, R.L.; Boegel, A.J.; Jenquin, U.P.; Kottwitz, D.A.; Lewallen, M.A.; Merrill, E.T.; Nolan, A.M.

    1979-12-01

    Nine alternative LWR fuel cycles are analyzed in terms of the isotopic content of the fuel material, the relative amounts of primary and recycled material, the uranium and thorium requirements, the fuel cycle costs and the fraction of energy which must be generated at secured sites. The fuel materials include low-enriched uranium (LEU), plutonium-uranium (MOX), highly-enriched uranium-thorium (HEU-Th), denatured uranium-thorium (DU-Th) and plutonium-thorium (Pu-Th). The analysis is based on tracing the material requirements of a generic pressurized water reactor (PWR) for a 30-year period at constant annual energy output. During this time period all the created fissile material is recycled unless its reactivity worth is less than 0.2% uranium enrichment plant tails

  2. Advanced steam cycles for light water reactors. Final report

    International Nuclear Information System (INIS)

    Mitchell, R.C.

    1975-07-01

    An appraisal of the potential of adding superheat to improve the overall LWR plant cycle performance is presented. The study assesses the economic and technical problems associated with the addition of approximately 500 0 F of superheat to raise the steam temperature to 1000 0 F. The practicality of adding either nuclear or fossil superheat to LWR's is reviewed. The General Electric Company Boiling Water Reactor (BWR) model 238-732 (BWR/6) is chosen as the LWR starting point for this evaluation. The steam conditions of BWR/6 are representative of LWR's. The results of the fossil superheat portion of the evaluation are considered directly applicable to all LWR's. In spite of the potential of a nuclear superheater to provide a substantial boost to the LWR cycle efficiency, nuclear superheat offers little promise of development at this time. There are difficult technical problems to resolve in the areas of superheat fuel design and emergency core cooling. The absence of a developed high integrity, high temperature fuel for operation in the steam/water environment is fundamental to this conclusion. Fossil superheat offers the potential opportunity to utilize fossil fuel supplies more efficiently than in any other mode of central station power generation presently available. Fossil superheat topping cycles evaluated included atmospheric fluidized beds (AFB), pressurized fluidized beds, pressurized furnaces, conventional furnaces, and combined gas/steam turbine cycles. The use of an AFB is proposed as the preferred superheat furnace. Fossil superheat provides a cycle efficiency improvement for the LWR of two percentage points, reduces heat rejection by 15 percent per kWe generated, increases plant electrical output by 54 percent, and burns coal with an incremental net efficiency of approximately 40 percent. This compares with a net efficiency of 36--37 percent which might be achieved with an all-fluidized bed fossil superheat plant design

  3. Environmentally assisted cracking of light-water reactor materials

    International Nuclear Information System (INIS)

    Chopra, O.K.; Chung, H.M.; Kassner, T.F.; Shack, W.J.

    1996-02-01

    Environmentally assisted cracking (EAC) of lightwater reactor (LWR) materials has affected nuclear reactors from the very introduction of the technology. Corrosion problems have afflicted steam generators from the very introduction of pressurized water reactor (PWR) technology. Shippingport, the first commercial PWR operated in the United States, developed leaking cracks in two Type 304 stainless steel (SS) steam generator tubes as early as 1957, after only 150 h of operation. Stress corrosion cracks were observed in the heat-affected zones of welds in austenitic SS piping and associated components in boiling-water reactors (BRWs) as early as 1965. The degradation of steam generator tubing in PWRs and the stress corrosion cracking (SCC) of austenitic SS piping in BWRs have been the most visible and most expensive examples of EAC in LWRs, and the repair and replacement of steam generators and recirculation piping has cost hundreds of millions of dollars. However, other problems associated with the effects of the environment on reactor structures and components am important concerns in operating plants and for extended reactor lifetimes. Cast duplex austenitic-ferritic SSs are used extensively in the nuclear industry to fabricate pump casings and valve bodies for LWRs and primary coolant piping in many PWRs. Embrittlement of the ferrite phase in cast duplex SS may occur after 10 to 20 years at reactor operating temperatures, which could influence the mechanical response and integrity of pressure boundary components during high strain-rate loading (e.g., seismic events). The problem is of most concern in PWRs where slightly higher temperatures are typical and cast SS piping is widely used

  4. Structural, mechanical and light yield characterisation of heat treated LYSO:Ce single crystals for medical imaging applications

    CERN Document Server

    Mengucci, P; Auffray, E; Barucca, G; Cecchi, C; Chipaux, R; Cousson, A; Davì, F; Di Vara, N; Rinaldi, D; Santecchia, E

    2015-01-01

    Five single crystals of cerium-doped lutetium yttrium oxyorthosilicate (LYSO:Ce) grown by the Czochralski method were submitted to structural characterisation by X-ray (XRD) and neutron (ND) diffraction, scanning (SEM) and transmission (TEM) electron microscopy and energy dispersive microanalysis (EDS). The Ultimate Tensile Strength (UTS), the Young Modulus (YM) and the Light Yield (LY) of the samples were also measured in order to correlate the mechanical and the optical behaviour of the crystals with the characteristics of their microstructure. Two of the samples analysed were also heat treated at 300 °C for 10 h to evidence possible variations induced by the temperature in the optical and mechanical response of the crystals. Results showed that the mean compositional variations evidenced by the structural analyses do not affect the mechanical and optical behaviour of the samples. On the contrary, the thermal treatment could induce the formation of coherent spherical particles (size 10 to 15 nm), not unifo...

  5. Light

    CERN Document Server

    Robertson, William C

    2003-01-01

    Why is left right and right left in the mirror? Baffled by the basics of reflection and refraction? Wondering just how the eye works? If you have trouble teaching concepts about light that you don t fully grasp yourself, get help from a book that s both scientifically accurate and entertaining with Light. By combining clear explanations, clever drawings, and activities that use easy-to-find materials, this book covers what science teachers and parents need to know to teach about light with confidence. It uses ray, wave, and particle models of light to explain the basics of reflection and refraction, optical instruments, polarization of light, and interference and diffraction. There s also an entire chapter on how the eye works. Each chapter ends with a Summary and Applications section that reinforces concepts with everyday examples. Whether you need a deeper understanding of how light bends or a good explanation of why the sky is blue, you ll find Light more illuminating and accessible than a college textbook...

  6. Sound intensity probe for ultrasonic field in water using light-emitting diodes and piezoelectric elements

    Science.gov (United States)

    Zeng, Xi; Mizuno, Yosuke; Nakamura, Kentaro

    2017-12-01

    The sound intensity vector provides useful information on the state of an ultrasonic field in water, since sound intensity is a vector quantity expressing the direction and magnitude of the sound field. In the previous studies on sound intensity measurement in water, conventional piezoelectric sensors and metal cables were used, and the transmission distance was limited. A new configuration of a sound intensity probe suitable for ultrasonic measurement in water is proposed and constructed for trial in this study. The probe consists of light-emitting diodes and piezoelectric elements, and the output signals are transmitted through fiber optic cables as intensity-modulated light. Sound intensity measurements of a 26 kHz ultrasonic field in water are demonstrated. The difference in the intensity vector state between the water tank with and without sound-absorbing material on its walls was successfully observed.

  7. Inactivation of Escherichia Coli O157:H7 and Salmonella Enterica on Blueberries in Water Using Ultraviolet Light.

    Science.gov (United States)

    Liu, Chuhan; Huang, Yaoxin; Chen, Haiqiang

    2015-07-01

    Ultraviolet light (UV) has antimicrobial effects, but the shadowing effect has limited its application. In this study, a novel setup using UV processing in agitated water was developed to inactivate Escherichia coli O157:H7 and Salmonella on blueberries. Blueberries were dip- or spot-inoculated with E. coli or Salmonella. Blueberries inoculated with E. coli were treated for 2 to 10 min with UV directly (dry UV) or immersed in agitated water during UV treatment (wet UV). E. coli was most easily killed on spot-inoculated blueberries with a 5.2-log reduction after 10-min wet UV treatment. Dip-inoculated blueberries were the most difficult to be decontaminated with only 1.6-log reduction after 10-min wet UV treatment. Wet UV treatment generally showed higher efficacies than dry UV treatment, achieving an average of 1.4 log more reduction for spot-inoculated blueberries. For dip-inoculated blueberries, chlorine washing and UV treatments were less effective, achieving blueberries were UV-treated while being immersed in agitated water containing 100 ppm SDS, 0.5% levulinic acid or 10 ppm chlorine. The 3 chemicals did not significantly enhance the wet UV treatment. Findings of this study suggest that UV treatment could be used as an alternative to chlorine washing for blueberries and potentially for other fresh produce. A novel UV light system for decontamination of blueberries in water was developed and evaluated. Results demonstrated that the decontamination efficacy of this system was generally as effective as chlorine washing, indicating that it could potentially be used as an alternative to chlorine washing for blueberries and other fresh produce. © 2015 Institute of Food Technologists®

  8. Investigation into the use of water based brake fluid for light loads ...

    African Journals Online (AJOL)

    The actual test of the formulated brake fluid was carried out with a Nissan Sunny vehicle model 1.5 within the speed range of 20km/hr to 80km/hr at the permanent campus· of University of Uyo and the· braking effiqiency obtained at test to its suitability for light loads. Keywords·: Water-based, Brake fluid properties, Light loads ...

  9. A Co(II)-Ru(II) dyad relevant to light-driven water oxidation catalysis.

    Science.gov (United States)

    López, Alejandro Montellano; Natali, Mirco; Pizzolato, Erica; Chiorboli, Claudio; Bonchio, Marcella; Sartorel, Andrea; Scandola, Franco

    2014-06-28

    Artificial photosynthesis aims at efficient water splitting into hydrogen and oxygen, by exploiting solar light. As a priority requirement, this process entails the integration of suitable multi-electron catalysts with light absorbing units, where charge separation is generated in order to drive the catalytic routines. The final goal could be the transposition of such an asset into a photoelectrocatalytic cell, where the two half-reactions, proton reduction to hydrogen and water oxidation to oxygen, take place at two appropriately engineered photoelectrodes. We herein report a covalent approach to anchor a Co(II) water oxidation catalyst to a Ru(II) polypyridine photosensitizer unit; photophysical characterisation and the catalytic activity of such a dyad in a light activated cycle are reported, and implications for the development of regenerative systems are discussed.

  10. Programme of research and development on plutonium recycling in light-water reactors

    International Nuclear Information System (INIS)

    1979-01-01

    This is the third annual progress report concerning the programme on plutonium recycling in light-water reactors (indirect action) of the Commission of the European Communities. It covers the year 1978 and follows the annual reports for 1977 (EUR 6002 EN) and 1976 (EUR 5780). The preliminary results obtained under the 1975-79 programme indicate that: (a) assuming that plutonium recycling in light-water reactors is industrially developed by the end of the century, the foreseeable radiological impact on both workers and the general public can be maintained within the limits of current radiation protection standards; (b) on the whole, there is a good knowledge and mastery of the specific aspects involved in the plutonium recycling in light-water reactors and in particular they indicate that plutonium fuels have a similar behaviour to uranium fuels

  11. A role for calcium hydroxide and dolomite in water: acceleration of the reaction under ultraviolet light.

    Science.gov (United States)

    Nagase, Hiroyasu; Tsujino, Hidekazu; Kurihara, Daisuke; Saito, Hiroshi; Kawase, Masaya

    2014-04-01

    Organic environmental pollutants are now being detected with remarkably high frequency in the aquatic environment. Photodegradation by ultraviolet light is sometimes used as a method for removing organic chemicals from water; however, this method is relatively inefficient because of the low degradation rates involved, and more efficient methods are under development. Here we show that the removal of various organic pollutants can be assisted by calcined dolomite in aqueous solution under irradiation with ultraviolet light. It was possible to achieve substantial removal of bisphenol A, chlorophenols, alkylphenols, 1-naphthol and 17β-estradiol. The major component of dolomite responsible for the removal was calcium hydroxide. Our results demonstrate that the use of calcium hydroxide with ultraviolet light irradiation can be a very effective method of rapidly removing organic environmental pollutants from water. This is a new role for calcium hydroxide and dolomite in water treatment. Copyright © 2013 Elsevier Ltd. All rights reserved.

  12. Physicochemical and Microbiological Analysis of Drinking Water Treated by Using Ozone

    International Nuclear Information System (INIS)

    Subedi, D.P.; Khadgi, A.; Tyata, R.B.; Wong, C.S.

    2012-01-01

    This study focused on the application of a Dielectric Barrier Discharge (DBD ) unit to produce highly oxidizing ozone molecules for the treatment of drinking water. The samples of water were collected from three different sources, namely tap, stone spout and tube-well in the Kathmandu valley. Various physical, chemical and micro-biological analyses were carried out to both the ozone treated and untreated samples of water for comparison. Our results indicated that ozone does not alter the physical characteristics, namely pH, conductivity and turbidity of water but it has significant effect on the chemical properties such as nitrate concentration, total hardness, calcium hardness, Fe(II) and Fe(III) concentration. It was observed that ozone efficiently precipitates ferrous ion into ferric ion and is effective in the removal of fecal coliform, a key element for various water related health problems in most of the developing countries. It is shown that the treatment with ozone leads to a significant reduction in the number of fecal coliform in the samples of drinking water from tap, stone spout and tube well with p values 0.00182, 0.026 and 5.8 x 10 -15 , respectively at 0.05 level of significance. (author)

  13. Thermohydraulics of emergency core cooling in light water reactors

    International Nuclear Information System (INIS)

    1989-10-01

    This report, by a group of experts of the OECD-NEA Committee on the Safety of Nuclear Installations, reviews the current state-of-knowledge in the field of emergency core cooling (ECC) for design-basis, loss-of-coolant accidents (LOCA) and core uncover transients in pressurized- and boiling-water reactors. An overview of the LOCA scenarios and ECC phenomenology is provided for each type of reactor, together with a brief description of their ECC systems. Separate-effects and integral-test facilities, which contribute to understanding and assessing the phenomenology, are reviewed together with similarity and scaling compromises. All relevant LOCA phenomena are then brought together in the form of tables. Each phenomenon is weighted in terms of its importance to the course of a LOCA, and appraised for the adequacy of its data base and analytical modelling. This qualitative procedure focusses attention on the modelling requirements of dominant LOCA phenomena and the current capabilities of the two-fluid models in two-phase flows. This leads into the key issue with ECC: quantitative code assessment and the application of system codes to predict with a well defined uncertainty the behaviour of a nuclear power plant. This issue, the methodologies being developed for code assessment and the question of how good is good enough are discussed in detail. Some general conclusions and recommendations for future research activities are provided

  14. Coastdown in light water reactors as a fuel management strategy

    International Nuclear Information System (INIS)

    Lobo, L.G.

    1980-12-01

    Improved uranium utilization by means of extended burnup via routine end-of-cycle coastdown has been analyzed, with a specific focus on pressurided water reactors. Both computer and simple analytic models have been developed to determine the optimal coastdown length. Coastdown has been compared with the use of higher fuel-enrichment to achieve comparable burnup values. Temperature and Power coastdown modes were analyzed and changes in the plant thermodynamic efficiency determined. Effects on fuel integrity due to coastdown were examined using a fuel reliability code (SPEAR). Finally the effects on coastdown duration of major parameters involved in charaterizing reactor operation and the economic enviroment were examined. It was found that natural uranium savings up to 7% could be achieved in a typical application by the use of routine pre-planned coast down up to the economic optimun. If coastdown is carried out all the way up to the economic breakeven point yellowcake savings sum up to 16%. Coastdown is substantially more effective than increasing enrichment to extend cycle length without coastdown. Thermodynamic efficiency does not change appreciably during coastdown, a circumstance which greatly simplifies modeling. Coastdown was found to have no statistically significant effect on predicted fuel failure rates. Finally, simple back-of-the evenlope analytic models were found to give an excellent estimate of coastdown duration to both the optimum and breakeven points, and to correctly track the functional behavior induced by all major variables

  15. Study of plutonium recycling physics in light water reactors

    International Nuclear Information System (INIS)

    Reuss, Paul

    1979-10-01

    A stock of plutonium from the reprocessing of thermal neutron reactor fuel is likely to appear in the next few years. The use of this plutonium as fuel replacing 235 U in thermal reactors is probably more interesting than simple stock-piling storage: immobilization of a capital which moreover would deteriorate by radioactive decay of isotope 241 also fissile and present to an appreciable extend in plutonium from reprocessing (half-life 15 years); recycling, on the other hand, will supply energy without complete degradation of the stock for fast neutron reactor loads, the burned matter having been partially renewed by conversion; furthermore the use of plutonium will meet the needs created by a temporary pressure on the naturel and/or enriched uranium market. For these two reasons the recycling of plutonium in thermal neutron reactors is being considered seriously today. The present work is confined to neutronic aspects and centres mainly on pressurized water-moderated reactors, the most highly developed at present in France. Four aspects of the problem are examined: 1. the physics of a plutonium-recycling reactor special features of neutronic phenomena with respect to the 'conventional' scheme of the 235 U burning reactor; 2. calculation of a plutonium-recycling reactor: adaptation of standard methods; 3. qualification of these calculations from the viewpoint of both data and inevitable approximations; 4. the fuel cycle and particularly the equivalence of fissile matters [fr

  16. Study of Pu consumption in Advanced Light Water Reactors

    International Nuclear Information System (INIS)

    1993-01-01

    Timely disposal of the weapons plutonium is of paramount importance to permanently safeguarding this material. GE's 1300 MWe Advanced Boiling Water Reactor (ABWR) has been designed to utilize fill] core loading of mixed uranium-plutonium oxide fuel. Because of its large core size, a single ABWR reactor is capable of disposing 100 metric tons of plutonium within 15 years of project inception in the spiking mode. The same amount of material could be disposed of in 25 years after the start of the project as spent fuel, again using a single reactor, while operating at 75 percent capacity factor. In either case, the design permits reuse of the stored spent fuel assemblies for electrical energy generation for the remaining life of the plant for another 40 years. Up to 40 percent of the initial plutonium can also be completely destroyed using ABWRS, without reprocessing, either by utilizing six ABWRs over 25 years or by expanding the disposition time to 60 years, the design life of the plants and using two ABWRS. More complete destruction would require the development and testing of a plutonium-base fuel with a non-fertile matrix for an ABWR or use of an Advanced Liquid Metal Reactor (ALMR). The ABWR, in addition, is fully capable of meeting the tritium target production goals with already developed target technology

  17. Light

    CERN Document Server

    Rivera, Andrea

    2017-01-01

    Light is all around us. Learn how it is used in art, technology, and engineering. Five easy-to-read chapters explain the science behind light, as well as its real-world applications. Vibrant, full-color photos, bolded glossary words, and a key stats section let readers zoom in even deeper. Aligned to Common Core Standards and correlated to state standards. Abdo Zoom is a division of ABDO.

  18. Improved biostability assessment of drinking water with a suite of test methods at a water supply treating eutrophic lake water.

    Science.gov (United States)

    van der Kooij, Dick; Martijn, Bram; Schaap, Peter G; Hoogenboezem, Wim; Veenendaal, Harm R; van der Wielen, Paul W J J

    2015-12-15

    Assessment of drinking-water biostability is generally based on measuring bacterial growth in short-term batch tests. However, microbial growth in the distribution system is affected by multiple interactions between water, biofilms and sediments. Therefore a diversity of test methods was applied to characterize the biostability of drinking water distributed without disinfectant residual at a surface-water supply. This drinking water complied with the standards for the heterotrophic plate count and coliforms, but aeromonads periodically exceeded the regulatory limit (1000 CFU 100 mL(-1)). Compounds promoting growth of the biopolymer-utilizing Flavobacterium johnsoniae strain A3 accounted for c. 21% of the easily assimilable organic carbon (AOC) concentration (17 ± 2 μg C L(-1)) determined by growth of pure cultures in the water after granular activated-carbon filtration (GACF). Growth of the indigenous bacteria measured as adenosine tri-phosphate in water samples incubated at 25 °C confirmed the low AOC in the GACF but revealed the presence of compounds promoting growth after more than one week of incubation. Furthermore, the concentration of particulate organic carbon in the GACF (83 ± 42 μg C L(-1), including 65% carbohydrates) exceeded the AOC concentration. The increased biomass accumulation rate in the continuous biofouling monitor (CBM) at the distribution system reservoir demonstrated the presence of easily biodegradable by-products related to ClO2 dosage to the GACF and in the CBM at 42 km from the treatment plant an iron-associated biomass accumulation was observed. The various methods applied thus distinguished between easily assimilable compounds, biopolymers, slowly biodegradable compounds and biomass-accumulation potential, providing an improved assessment of the biostability of the water. Regrowth of aeromonads may be related to biomass-turnover processes in the distribution system, but establishment of quantitative relationships is needed for

  19. General application of system event tree analysis to light water reactors

    International Nuclear Information System (INIS)

    Asselin, S.V.; Carlson, D.D.

    1977-01-01

    The system event tree is a key element in the comparison of light water reactors when considering Reactor Safety Study (RSS) factors such as risk and dominant accident sequences. The development of system event trees involves drawing on the RSS experience and adapting the methodology to reactor plants that may differ considerably, in system functions and interactions, from the RSS plants. This paper describes the methods for the general application of system event trees to light water reactors and is based on work done by Sandia Laboratories for the Nuclear Regulatory Commission on the Reactor Safety Study Methodology Applications Program

  20. Flow-induced vibration for light-water reactors. Progress report, April 1978-December 1979

    International Nuclear Information System (INIS)

    Schardt, J.F.

    1980-03-01

    Flow-Induced vibration for Light Water Reactors (FIV for LWRs) is a four-year program designed to improve the FIV performance of light water reactors through the development of design criteria, analytical models for predicting behavior of components, general scaling laws to improve the accuracy of reduced-scale tests, and the identification of high FIV risk areas. The program commenced December 1, 1976, but was suspended on September 30, 1978, due to a shift in Department of Energy (DOE) priorities away from LWR productivity/availability. It was reinitiated as of August 1, 1979. This progress report summarizes the accomplishments achieved during the period from April 1978 to December 1979

  1. Investigation into the Use of Water Based Brake Fluid for Light Loads

    Directory of Open Access Journals (Sweden)

    W. A. Akpan

    2012-12-01

    Full Text Available This paper addresses the possibility of using water based fluid as a brake fluid for light loads. Characterization of both standard and water based braked fluids formulated was carried out. The properties of the latter were compared with that of a standard commercial brake fluid. The actual test of the formulated brake fluid was carried out with a Nissan Sunny vehicle model 1.5 within the speed range of 20km/hr to 80km/hr at the permanent campus of University of Uyo and the braking efficiency obtained attest to its suitability for light loads.

  2. Light Refraction by Water as a Rationale for the Poggendorff Illusion

    DEFF Research Database (Denmark)

    Bozhevolnyi, Sergey I.

    2017-01-01

    The Poggendorff illusion in its classical form of parallel lines interrupting a transversal is viewed from the perspective of being related to the everyday experience of observing the light refraction in water. It is argued that if one considers a transversal to be a light ray in air...... and the parallel lines to form an occluding strip of a medium with the refractive index being between that of air and water, then one should be able to account, both qualitatively and quantitatively, for most of the features associated with the Poggendorff illusion. Statistical treatment of the visual experiments...

  3. Effect on Compressive Strength of Concrete Using Treated Waste Water for Mixing and Curing of Concrete

    Directory of Open Access Journals (Sweden)

    Humaira Kanwal

    2018-04-01

    Full Text Available Effective utilization of the available resources is imperative approach to achieve the apex of productivity. The modern world is focusing on the conditioning, sustainability and recycling of the assets by imparting innovative techniques and methodologies. Keeping this in view, an experimental study was conducted to evaluate the strength of concrete made with treated waste water for structural use. In this study ninetysix cylinders of four mixes with coarse aggregates in combination with FW (Fresh Water, WW (Wastewater, TWW (Treated Wastewater and TS (Treated Sewagewere prepared. The workability of fresh concrete was checked before pouring of cylinders. The test cylinders were left for 7, 14, 21 and 28 days for curing. After curing, the compressive strength was measured on hardened concrete cylinders accordingly. Test results showed that workability of all the four mixes were between 25-50mm but ultimate compressive strength of concrete with WW was decreased and with TWW, TS at the age of 28 days do not change significantly. This research will open a new wicket in the horizon of recycling of construction materials. The conditioning and cyclic utilization will reduce the cost of the construction and building materials as well as minimize the use of natural resources. This novelty and calculating approach will save our natural assets and resources.

  4. Analysis and utilization of plasma treated water for food and agricultural interest

    Science.gov (United States)

    Park, Sanghoo; Lim, Youbong; Park, Joo Young; Choe, Wonho; Kim, Hyun-Joo; Yong, Hae In; Jo, Cheorun; Jung, Samooel

    2015-09-01

    Attention on aqueous chemical species produced in plasma-treated solutions through plasma-liquid interactions has been increased because of its strong relation to bio/medical and food applications. The long-lived and reactive oxygen and nitrogen species such as hydrogen peroxide, ozone, superoxide anion, and oxyacids play a crucial role in those applications. The plasma treatment brings about absorption of these species into the target liquid and also induces changes in liquid characteristics and composition via photolysis by plasma UV emission and post-discharge reactions. In this presentation, we discuss the result of our investigation of the chemical properties related to the two main oxyacids, HNO2 and HNO3, in plasma treated water (PTW). Water was treated in close proximity by our SDBD system developed specifically to meet the application requirements. The chemical properties of the solution varied gradually over the treatment time and storage time. Here we report the result of our experiment, theoretical analysis, and their consistency. Furthermore, the dependence of the nitrite ion production yield on the dissipated power, treatment time, and dielectric material will be discussed. Based on the revealed fundamental characteristics, the utilization of PTW in the meat curing process as one of the nitrite sources will be briefly demonstrated. In terms of sausage quality, there were no noticeable effects of PTW on the total aerobic bacteria counts, color, and peroxide values of sausages compared with those using celery powder and sodium nitrite.

  5. 78 FR 64029 - Cost-Benefit Analysis for Radwaste Systems for Light-Water-Cooled Nuclear Power Reactors

    Science.gov (United States)

    2013-10-25

    ...-Water-Cooled Nuclear Power Reactors AGENCY: Nuclear Regulatory Commission. ACTION: Regulatory guide... (RG) 1.110, ``Cost-Benefit Analysis for Radwaste Systems for Light-Water-Cooled Nuclear Power Reactors... components for light water nuclear power reactors. ADDRESSES: Please refer to Docket ID NRC-2013-0237 when...

  6. Instability of infiltration fronts due to long term irrigation of treated waste water

    Science.gov (United States)

    Leuther, Frederic; Weller, Ulrich; Schlüter, Steffen; Wallach, Rony; Vogel, Hans-Jörg

    2017-04-01

    Irrigation of treated waste water (TWW) is a common practice in arid and semiarid areas as it combines a sustainable, all-season available water recourse and the recycling of nutrients. Previous studies have shown that organic compounds can affect wettability of mineral surfaces and may change soil structure. Since TWW provides high loads of organic material, long-term irrigation can lead to persistent structure alteration, hydrophobicity, preferential flow, and leaching of chemicals and nutrients. In this study we (i) developed a new approach to quantify water movement in undisturbed soil cores via X-ray radiography and (ii) detected instabilities of water infiltration in soils irrigated with TWW since more than 20 years. We investigated soil samples from two orchards in Israel with long-term irrigation of TWW, one of them additionally irrigated with fresh water. The samples provide two different soil textures, and two different treatments of irrigation: fresh water and TWW. Furthermore, we included seasonal dependencies (dry season and rainy season) to determine persistency of effects. Undisturbed, cylindrical soil samples were taken from the upper soil layer (0-20cm) and irrigation experiments were performed inside an X-ray system. Via image analysis we quantified the infiltration front propagation and spatial moisture distribution as a function of time and repeated the experiments with different initial moisture contents. In this study we show that the stability of infiltration front in these soils is dependent on the irrigated water quality and on the initial water content. Furthermore, we demonstrate that long-term irrigation of TWW can lead to a persistent change in wettability, independent of the season. This study provides experimental evidence about importance of optimizing irrigation management to prevent preferential flow.

  7. Assessment of Trace Metal Ions on Raw and Treated Water in Dakahlia Drinking water Purification Stations .Behaviour of aluminium in water purification plants

    International Nuclear Information System (INIS)

    El-Defrawy, M.M.; El-Fadaly, H.; El-Zawawy, F.; Makia, D.

    1999-01-01

    The technology of improvement of water quality at water purification plants can be characterised by a large diversity of method and processes employed and by substantial differences in the design and process structure and equipment. The effect of operational parameters as ph, pre-, post- chlorination, coagulant index and mixing intensities on the level of some metal ions concentration in different sources of drinking water plants were studied. Results of the chemical analysis indicated that the dissolved and total AI 3+ concentration in treated water was much higher than raw water and sometimes with values over the international maximum limit. Much of the overall variation in aqua aluminium ion in treated water could be explained on the basis of ph, solubility, and filtration models efficiency, while ions as Fe 3+ and Mn 2+ were found within the acceptable limits. The data obtained indicated that relation between watershed inputs (CI 2 , H CI, alum dose) and output of soluble aluminium was not necessary simple and straightforward. The investigated water samples were collected from main stations and compact units in Dakahlia Governorate

  8. Rapid water disinfection using vertically aligned MoS2 nanofilms and visible light

    Science.gov (United States)

    Liu, Chong; Kong, Desheng; Hsu, Po-Chun; Yuan, Hongtao; Lee, Hyun-Wook; Liu, Yayuan; Wang, Haotian; Wang, Shuang; Yan, Kai; Lin, Dingchang; Maraccini, Peter A.; Parker, Kimberly M.; Boehm, Alexandria B.; Cui, Yi

    2016-12-01

    Solar energy is readily available in most climates and can be used for water purification. However, solar disinfection of drinking water mostly relies on ultraviolet light, which represents only 4% of the total solar energy, and this leads to a slow treatment speed. Therefore, the development of new materials that can harvest visible light for water disinfection, and so speed up solar water purification, is highly desirable. Here we show that few-layered vertically aligned MoS2 (FLV-MoS2) films can be used to harvest the whole spectrum of visible light (∼50% of solar energy) and achieve highly efficient water disinfection. The bandgap of MoS2 was increased from 1.3 to 1.55 eV by decreasing the domain size, which allowed the FLV-MoS2 to generate reactive oxygen species (ROS) for bacterial inactivation in the water. The FLV-MoS2 showed a ∼15 times better log inactivation efficiency of the indicator bacteria compared with that of bulk MoS2, and a much faster inactivation of bacteria under both visible light and sunlight illumination compared with the widely used TiO2. Moreover, by using a 5 nm copper film on top of the FLV-MoS2 as a catalyst to facilitate electron-hole pair separation and promote the generation of ROS, the disinfection rate was increased a further sixfold. With our approach, we achieved water disinfection of >99.999% inactivation of bacteria in 20 min with a small amount of material (1.6 mg l-1) under simulated visible light.

  9. Boreal Tree Light- and Water-Use: Asynchronous, Diverging, yet Complementary

    Science.gov (United States)

    Pappas, C.; Baltzer, J. L.; Barr, A.; Black, T. A.; Bohrer, G.; Detto, M.; Maillet, J.; Matheny, A. M.; Roy, A.; Sonnentag, O.; Stephens, J.

    2017-12-01

    Water stress has been suggested as a key mechanism behind the contemporary increase in tree mortality rates in northwestern North America. However, a detailed analysis of boreal tree light- and water-use strategies as well as their interspecific differences are still lacking. Here, we examine the tree hydraulic behaviour of co-occurring larch (Larix laricina) and black spruce (Picea mariana), two characteristic boreal tree species, near the southern limit of the boreal ecozone in central Canada. Sap flux density (Js) and concurrently recorded stem radius fluctuations and meteorological conditions are used to quantify tree hydraulic functioning and to scrutinize tree light- and water-use strategies. Our analysis reveals an asynchrony in the diel hydrodynamics of the two species with the initial rise in Js occurring two hours earlier in larch than in black spruce. Structural differences in the crown architecture of larch and black spruce lead to interspecific differences in light harvesting that can explain the observed asynchrony in their hydraulic function. Furthermore, the two species exhibit diverging stomatal regulation strategies with larch employing relatively isohydric whereas black spruce anisohydric behaviour. Such asynchronous and diverging tree-level light- and water-use strategies provide new insights into the ecosystem-level complementarity of tree form and function, with implications for understanding boreal forests' water and carbon dynamics and resilience to environmental stress.

  10. Materials Degradation in Light Water Reactors: Life After 60,???

    Energy Technology Data Exchange (ETDEWEB)

    Busby, Jeremy T [ORNL; Nanstad, Randy K [ORNL; Stoller, Roger E [ORNL; Feng, Zhili [ORNL; Naus, Dan J [ORNL

    2008-04-01

    Nuclear reactors present a very harsh environment for components service. Components within a reactor core must tolerate high temperature water, stress, vibration, and an intense neutron field. Degradation of materials in this environment can lead to reduced performance, and in some cases, sudden failure. A recent EPRI-led study interviewed 47 US nuclear utility executives to gauge perspectives on long-term operation of nuclear reactors. Nearly 90% indicated that extensions of reactor lifetimes to beyond 60 years were likely. When polled on the most challenging issues facing further life extension, two-thirds cited plant reliability as the key issue with materials aging and cable/piping as the top concerns for plant reliability. Materials degradation within a nuclear power plant is very complex. There are many different types of materials within the reactor itself: over 25 different metal alloys can be found with can be found within the primary and secondary systems, not to mention the concrete containment vessel, instrumentation and control, and other support facilities. When this diverse set of materials is placed in the complex and harsh environment coupled with load, degradation over an extended life is indeed quite complicated. To address this issue, the USNRC has developed a Progressive Materials Degradation Approach (NUREG/CR-6923). This approach is intended to develop a foundation for appropriate actions to keep materials degradation from adversely impacting component integrity and safety and identify materials and locations where degradation can reasonably be expected in the future. Clearly, materials degradation will impact reactor reliability, availability, and potentially, safe operation. Routine surveillance and component replacement can mitigate these factors, although failures still occur. With reactor life extensions to 60 years or beyond or power uprates, many components must tolerate the reactor environment for even longer times. This may increase

  11. Materials Degradation in Light Water Reactors: Life After 60,

    International Nuclear Information System (INIS)

    Busby, Jeremy T; Nanstad, Randy K; Stoller, Roger E; Feng, Zhili; Naus, Dan J

    2008-01-01

    Nuclear reactors present a very harsh environment for components service. Components within a reactor core must tolerate high temperature water, stress, vibration, and an intense neutron field. Degradation of materials in this environment can lead to reduced performance, and in some cases, sudden failure. A recent EPRI-led study interviewed 47 US nuclear utility executives to gauge perspectives on long-term operation of nuclear reactors. Nearly 90% indicated that extensions of reactor lifetimes to beyond 60 years were likely. When polled on the most challenging issues facing further life extension, two-thirds cited plant reliability as the key issue with materials aging and cable/piping as the top concerns for plant reliability. Materials degradation within a nuclear power plant is very complex. There are many different types of materials within the reactor itself: over 25 different metal alloys can be found with can be found within the primary and secondary systems, not to mention the concrete containment vessel, instrumentation and control, and other support facilities. When this diverse set of materials is placed in the complex and harsh environment coupled with load, degradation over an extended life is indeed quite complicated. To address this issue, the USNRC has developed a Progressive Materials Degradation Approach (NUREG/CR-6923). This approach is intended to develop a foundation for appropriate actions to keep materials degradation from adversely impacting component integrity and safety and identify materials and locations where degradation can reasonably be expected in the future. Clearly, materials degradation will impact reactor reliability, availability, and potentially, safe operation. Routine surveillance and component replacement can mitigate these factors, although failures still occur. With reactor life extensions to 60 years or beyond or power uprates, many components must tolerate the reactor environment for even longer times. This may increase

  12. [Impact of Light Polarization on the Measurement of Water Particulate Backscattering Coefficient].

    Science.gov (United States)

    Liu, Jia; Gong, Fang; He, Xian-qiang; Zhu, Qian-kun; Huang, Hai-qing

    2016-01-01

    Particulate backscattering coefficient is a main inherent optical properties (IOPs) of water, which is also a determining factor of ocean color and a basic parameter for inversion of satellite ocean color remote sensing. In-situ measurement with optical instruments is currently the main method for obtaining the particulate backscattering coefficient of water. Due to reflection and refraction by the mirrors in the instrument optical path, the emergent light source from the instrument may be partly polarized, thus to impact the measurement accuracy of water backscattering coefficient. At present, the light polarization of measuring instruments and its impact on the measurement accuracy of particulate backscattering coefficient are still poorly known. For this reason, taking a widely used backscattering coefficient measuring instrument HydroScat6 (HS-6) as an example in this paper, the polarization characteristic of the emergent light from the instrument was systematically measured, and further experimental study on the impact of the light polarization on the measurement accuracy of the particulate backscattering coefficient of water was carried out. The results show that the degree of polarization(DOP) of the central wavelength of emergent light ranges from 20% to 30% for all of the six channels of the HS-6, except the 590 nm channel from which the DOP of the emergent light is slightly low (-15%). Therefore, the emergent light from the HS-6 has significant polarization. Light polarization has non-neglectable impact on the measurement of particulate backscattering coefficient, and the impact degree varies with the wave band, linear polarization angle and suspended particulate matter (SPM) concentration. At different SPM concentrations, the mean difference caused by light polarization can reach 15.49%, 11.27%, 12.79%, 14.43%, 13.76%, and 12.46% in six bands, 420, 442, 470, 510, 590, and 670 nm, respectively. Consequently, the impact of light polarization on the

  13. Treating infected diabetic wounds with superoxidized water as anti-septic agent: a preliminary experience

    International Nuclear Information System (INIS)

    Hadi, S.F.; Khaliq, T.; Zubair, M.; Saaiq, M.; Sikandar, I.

    2007-01-01

    To evaluate the effectiveness of superoxidized water (MicrocynTM) in diabetic patients with different wounds. One hundred known diabetic patients were enrolled. Half were randomized to the intervention group (those whose wounds were managed with superoxidized water) and half to the control group (whose wounds were treated with normal saline) using a table of random numbers. The two groups were matched for age, gender, duration of diabetes and category of wound. All patients received appropriate surgical treatment for their wounds as required. Local wound treatment was carried out daily using superoxidized water soaked gauzes on twice daily basis in the intervention group and normal saline in the control group. The treatment was continued until wound healing. The main outcome measures were duration of hospital stay, downgrading of the wound category, wound healing time and need for interventions such as amputation. Statistically significant differences were found in favour of the superoxidized water group with respect to duration of hospital stay, downgrading of the wound category and wound healing time. Although the initial results of employing superoxidized water for the management of infected diabetic wounds are encouraging, further multicentre clinical trials are warranted before this antiseptic is recommended for general use. It may offer an economical alternative to other expensive antiseptics with positive impact on the prevailing infection rates, patient outcomes and patient satisfaction. (author)

  14. Flow-induced vibration for light water reactors. Program final report

    International Nuclear Information System (INIS)

    Corr, J.E.

    1983-03-01

    The Flow-Induced Vibrations for Light Water Reactors Program was a five-year effort to develop basic knowledge and understanding needed to improve the flow-induced vibration design of light water reactors. Major tasks included analytical and test investigations of the flow-induced vibration of cylinders in isolation and arrays in smooth and turbulent single-vibration testing of reactor components including reactor inlet plenum components, jet pumps, low-pressure coolant injection coupling, and fuel rods. Cases of self-excited limit cycle response were encountered which required design modifications. The fuel rod tests were made in axially flowing water and steam/water mixtures under adiabatic and boiling conditions

  15. Light-dependent changes in outer retinal water diffusion in rats in vivo.

    Science.gov (United States)

    Bissig, David; Berkowitz, Bruce A

    2012-01-01

    To test the hypothesis that in rats, intraretinal light-dependent changes on diffusion-weighted magnetic resonance imaging (MRI) in vivo are consistent with known retinal layer-specific physiology. In male Sprague-Dawley rats, retinal morphology (thickness, extent, surface area, volume) and intraretinal profiles of the apparent diffusion coefficient (ADC, i.e., water mobility) parallel and perpendicular to the optic nerve were measured in vivo using quantitative MRI methods during light and dark stimulation. The parallel ADC in the posterior half of the avascular, photoreceptor-dominated outer retina was significantly higher in light than dark, and this pattern was reversed (dark>light) in the anterior outer retina. The perpendicular ADC in the posterior outer retina was similar in light and dark, but was significantly higher in dark than light in the anterior outer retina. No light-dark changes in the inner retina were noted. We identified light-dependent intraretinal diffusion changes that reflected established stimulation-based changes in outer retinal hydration. These findings are expected to motivate future applications of functional diffusion-based MRI in blinding disorders of the outer retina.

  16. Removal Cu(II ions from water using sulphuric acid treated Lagenaria vulgaris Shell (Cucurbitaceae

    Directory of Open Access Journals (Sweden)

    Ljupković, R.B.

    2011-09-01

    Full Text Available Removal of Cu(II ions from water solutions by sulphuric acid treated Lagenaria vulgaris shell (ccLVB was studied. Batch experiments were done by shaking a fixed mass of biosorbent (1.0 g with 250 cm3 of 50.0 mg dm–3 Cu(II solutions, at pH ranged from 2 up to 6. Metal concentration in the filtrates as well as in the initial solution was determined by flame atomic absorption spectrometry. Results show that efficiency of Cu(II ions uptake by sulphuric acid treated Lagenaria vulgaris shell is significantly greater than raw Lagenaria vulgaris biosorbent. In addition, there is no significant effect of initial pH of solution on Cu(II ions uptake by ccLVB and obtained biosorbent can be applied in a wide range of pH.

  17. Water hammer caused by rapid gas production in a severe accident in a light water reactor

    International Nuclear Information System (INIS)

    Inasaka, Fujio; Adachi, Masaki; Aya, Izuo; Nariai, Hideki; Shiozaki, Kohki

    2005-01-01

    We investigated the water hammer caused by striking of water mass pushed up by a rapidly growing bubble and its scale effects using two cylindrical model containment vessels of 1.0 and 0.428 m diameters. We also closely observed the movement of water mass and the growing bubble in the vessels. In these experiments, rapid bubble growth was simulated by injecting high-pressure air into a water pool. It was clarified that the water mass was pushed up without any air penetration until the water level reached a certain elevation. On the basis of all data, experimental correlations for estimating the height and striking velocity of the water mass with coherency were proposed, and the water hammer pressure for exerting large forces on the structures was quantitatively evaluated. (author)

  18. Light

    CERN Document Server

    Ditchburn, R W

    1963-01-01

    This classic study, available for the first time in paperback, clearly demonstrates how quantum theory is a natural development of wave theory, and how these two theories, once thought to be irreconcilable, together comprise a single valid theory of light. Aimed at students with an intermediate-level knowledge of physics, the book first offers a historical introduction to the subject, then covers topics such as wave theory, interference, diffraction, Huygens' Principle, Fermat's Principle, and the accuracy of optical measurements. Additional topics include the velocity of light, relativistic o

  19. The morphological changes of Ascaris lumbricoides ova in sewage sludge water treated by gamma irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Shamma, M. E-mail: atom@sy.net; Al-Adawi, M.A

    2002-10-01

    Untreated wastewater sampled from Damascus sewage water treatment plant containing nematode Ascaris lumbricoides ova were treated using gamma irradiation (doses between 1.5 and 8 kGy), immediately after irradiation the morphological and developmental status of eggs was examined microscopically. Major morphological changes of the contents of the eggs were detected. These eggs were incubated for 8 weeks, after this period no larvae 'inside the eggs' were observed. Thus the morphological changes can be used as a viable parameter.

  20. Low-intensity blue-enriched white light (750 lux) and standard bright light (10 000 lux) are equally effective in treating SAD. A randomized controlled study

    NARCIS (Netherlands)

    Meesters, Ybe; Dekker, Vera; Schlangen, Luc J. M.; Bos, Elske H.; Ruiter, Martine J.

    2011-01-01

    Background: Photoreceptor cells containing melanopsin play a role in the phase-shifting effects of short-wavelength light. In a previous study, we compared the standard light treatment (SLT) of SAD with treatment using short-wavelength blue-enriched white light (BLT). Both treatments used the same

  1. Recent progress in oxynitride photocatalysts for visible-light-driven water splitting.

    Science.gov (United States)

    Takata, Tsuyoshi; Pan, Chengsi; Domen, Kazunari

    2015-06-01

    Photocatalytic water splitting into hydrogen and oxygen is a method to directly convert light energy into storable chemical energy, and has received considerable attention for use in large-scale solar energy utilization. Particulate semiconductors are generally used as photocatalysts, and semiconductor properties such as bandgap, band positions, and photocarrier mobility can heavily impact photocatalytic performance. The design of active photocatalysts has been performed with the consideration of such semiconductor properties. Photocatalysts have a catalytic aspect in addition to a semiconductor one. The ability to control surface redox reactions in order to efficiently produce targeted reactants is also important for photocatalysts. Over the past few decades, various photocatalysts for water splitting have been developed, and a recent main concern has been the development of visible-light sensitive photocatalysts for water splitting. This review introduces the study of water-splitting photocatalysts, with a focus on recent progress in visible-light induced overall water splitting on oxynitride photocatalysts. Various strategies for designing efficient photocatalysts for water splitting are also discussed herein.

  2. Light Illuminated α−Fe2O3/Pt Nanoparticles as Water Activation Agent for Photoelectrochemical Water Splitting

    Science.gov (United States)

    Li, Xiaodong; Wang, Zhi; Zhang, Zemin; Chen, Lulu; Cheng, Jianli; Ni, Wei; Wang, Bin; Xie, Erqing

    2015-01-01

    The photoelectrochemical (PEC) water splitting is hampered by strong bonds of H2O molecules and low ionic conductivity of pure water. The photocatalysts dispersed in pure water can serve as a water activation agent, which provides an alternative pathway to overcome such limitations. Here we report that the light illuminated α−Fe2O3/Pt nanoparticles may produce a reservoir of reactive intermediates including H2O2, ·OH, OH− and H+ capable of promoting the pure water reduction/oxidation half−reactions at cathode and highly photocatalytic−active TiO2/In2S3/AgInS2 photoanode, respectively. Remarkable photocurrent enhancement has been obtained with α−Fe2O3/Pt as water activation agent. The use of α−Fe2O3/Pt to promote the reactivity of pure water represents a new paradigm for reproducible hydrogen fuel provision by PEC water splitting, allowing efficient splitting of pure water without adding of corrosive chemicals or sacrificial agent. PMID:25773684

  3. Light illuminated α-Fe2O3/Pt nanoparticles as water activation agent for photoelectrochemical water splitting.

    Science.gov (United States)

    Li, Xiaodong; Wang, Zhi; Zhang, Zemin; Chen, Lulu; Cheng, Jianli; Ni, Wei; Wang, Bin; Xie, Erqing

    2015-03-16

    The photoelectrochemical (PEC) water splitting is hampered by strong bonds of H2O molecules and low ionic conductivity of pure water. The photocatalysts dispersed in pure water can serve as a water activation agent, which provides an alternative pathway to overcome such limitations. Here we report that the light illuminated α-Fe2O3/Pt nanoparticles may produce a reservoir of reactive intermediates including H2O2, ·OH, OH(-) and H(+) capable of promoting the pure water reduction/oxidation half-reactions at cathode and highly photocatalytic-active TiO2/In2S3/AgInS2 photoanode, respectively. Remarkable photocurrent enhancement has been obtained with α-Fe2O3/Pt as water activation agent. The use of α-Fe2O3/Pt to promote the reactivity of pure water represents a new paradigm for reproducible hydrogen fuel provision by PEC water splitting, allowing efficient splitting of pure water without adding of corrosive chemicals or sacrificial agent.

  4. European research activities within the project: High Performance Light Water Reactor phase 2 (HPLWR phase 2)

    Energy Technology Data Exchange (ETDEWEB)

    Starflinger, J.; Schulenberg, T. [Forschungszentrum Karlsruhe GmbH, Institute for Nuclear and Energy Technologies, Karlsruhe (Germany); Marsault, P. [CEA Cadarache (DER/SESI), 13 - Saint Paul lez Durance (France). Dept. d' Etudes des Reacteurs; Bittermann, D. [AREVA NP, NEPR-G, Erlangen (Germany); Maraczy, C. [AEKI-KFKI, Budapest (Hungary); Laurien, E. [Stuttgart Univ. IKE (Germany); Lycklama, J.A. [NRG Petten, NL (Netherlands); Anglart, H. [KTH Energy Technology, Stockholm (Sweden); Aksan, N. [Paul Scherrer Institut CH, Villigen PSI (Switzerland); Ruzickova, M. [UJV Rez plc, Husinec-Rez c.p. (Czech Republic); Heikinheimo, L. [VTT, FIN (Finland)

    2007-07-01

    The High Performance Light Water Reactor (HPLWR) is a Light Water Reactor (LWR) operating at supercritical pressure (25 MPa). It belongs to the six reactors currently being investigated under the framework of the Generation IV International Forum. The most visible advantage of the HPLWR shall be the low construction costs in the order of 1000 Euro/kWe, because of size reduction of components and buildings compared to current Light Water Reactors, and the low electricity production costs which are targeted at 3-4 cents/kWh. In Europe, investigations on the HPLWR have been integrated into a joint research project, called High Performance Light Water Reactor Phase 2 (HPLWR Phase 2), which is co-funded by the European Commission. Within 42 months, ten partners from eight European countries working on critical scientific issues shall show the feasibility of the HPLWR concept. This paper reports on 5 points relevant for HPLWR: 1) design and integration, 2) core design, 3) safety, 4) materials, and 5) heat transfer. The final goal is to assess the future potential of this reactor in the electricity market.

  5. Pigment specific in vivo light absorption of phytoplankton from estuarine, coastal and oceanic waters

    DEFF Research Database (Denmark)

    Stæhr, A.; Markager, S.; Sand-Jensen, K.

    2004-01-01

    -chemical environment from estuaries, over coastal, to oceanic waters, no clear relationships were found between a* ph and the prevailing light, temperature, salinity and nutrient concentrations, indicating that short-term cellular acclimation was of minor importance for the observed variability in a* ph. The clear...

  6. Generic environmental impact statement on handling and storage of spent light water power reactor fuel. Appendices

    International Nuclear Information System (INIS)

    1978-03-01

    Detailed appendices are included with the following titles: light water reactor fuel cycle, present practice, model 1000MW(e) coal-fired power plant, increasing fuel storage capacity, spent fuel transshipment, spent fuel generation and storage data (1976-2000), characteristics of nuclear fuel, and ''away-from-reactor'' storage concept

  7. Light Water Reactor Sustainability Constellation Pilot Project FY11 Summary Report

    International Nuclear Information System (INIS)

    Johansen, R.

    2011-01-01

    Summary report for Fiscal Year 2011 activities associated with the Constellation Pilot Project. The project is a joint effor between Constellation Nuclear Energy Group (CENG), EPRI, and the DOE Light Water Reactor Sustainability Program. The project utilizes two CENG reactor stations: R.E. Ginna and Nine Point Unit 1. Included in the report are activities associate with reactor internals and concrete containments.

  8. GENERIC, COMPONENT FAILURE DATA BASE FOR LIGHT WATER AND LIQUID SODIUM REACTOR PRAs

    Energy Technology Data Exchange (ETDEWEB)

    S. A. Eide; S. V. Chmielewski; T. D. Swantz

    1990-02-01

    A comprehensive generic component failure data base has been developed for light water and liquid sodium reactor probabilistic risk assessments (PRAs) . The Nuclear Computerized Library for Assessing Reactor Reliability (NUCLARR) and the Centralized Reliability Data Organization (CREDO) data bases were used to generate component failure rates . Using this approach, most of the failure rates are based on actual plant data rather than existing estimates .

  9. A light water excess heat reaction suggests that cold fusion may be alkali-hydrogen fusion

    International Nuclear Information System (INIS)

    Bush, R.T.

    1992-01-01

    This paper reports that Mills and Kneizys presented data in support of a light water excess heat reaction obtained with an electrolytic cell highly reminiscent of the Fleischmann-Pons cold fusion cell. The claim of Mills and Kneizys that their excess heat reaction can be explained on the basis of a novel chemistry, which supposedly also explains cold fusion, is rejected in favor of their reaction being, instead, a light water cold fusion reaction. It is the first known light water cold fusion reaction to exhibit excess heat, it may serve as a prototype to expand our understanding of cold fusion. From this new reactions are deduced, including those common to past cold fusion studies. This broader pattern of nuclear reactions is typically seen to involve a fusion of the nuclides of the alkali atoms with the simplest of the alkali-type nuclides, namely, protons, deuterons, and tritons. Thus, the term alkali-hydrogen fusion seems appropriate for this new type of reaction with three subclasses: alkali-hydrogen fusion, alkali-deuterium fusion, and alkali-tritium fusion. A new three-dimensional transmission resonance model (TRM) is sketched. Finally, preliminary experimental evidence in support of the hypothesis of a light water nuclear reaction and alkali-hydrogen fusion is reported. Evidence is presented that appears to strongly implicate the transmission resonance phenomenon of the new TRM

  10. Release of natural radionuclides in the Czech Republic - from water treatment plants where water from underground water sources is treated

    International Nuclear Information System (INIS)

    Sinaglova, R.

    2014-01-01

    In this abstract author deals with the treatment of drinking water in the Czech Republic with removing of natural radionuclides as well as with treatment of filter cartridges. The advantage of these technologies is that flushing is not required so no wastewater occurs. Used ion exchangers with higher content of uranium are processed in the chemical treatment of uranium ores, managed by DIAMO, state enterprise. (authors)

  11. Process of collecting tritium produced in light or heavy water moderated reactor

    International Nuclear Information System (INIS)

    Tachikawa, Enzo; Aratono, Yasuyuki; Takeda, Tsuneo.

    1973-01-01

    Purpose: To collect effectively tritium produced by nuclear reaction in coolant water of reactor, by means of transferring tritium to gaseous phase as tritium hydride, in the presence of compound comprising hydrogen whose combining energy is less than 95 Kcal/mol. Constitution: Process of collecting tritium produced by nuclear reaction in light or heavy water moderated and cooled reactor, including a step of adding compound comprising hydrogen atom, the combining energy of said hydrogen atom is less than 95 Kcal/mol, and a step of collecting tritium in the form of tritium hydride from coolant water. (M. K.)

  12. INACTIVATION OF PATHOGENIC BACTERIA USING PULSED UV-LIGHT AND ITS APPLICATION IN WATER DISINFECTION AND QUALITY CONTROL

    Directory of Open Access Journals (Sweden)

    M. K. Sharifi-Yazdi H. Darghahi

    2006-09-01

    Full Text Available The lethality of pulsed ultra-violet (UV rich light for the inactivation of pathogenic bacteria has been investigated. A low pressure xenon filled flash lamps that produced UV intensities have been used. The pulsed operation of the system enable the release of electrical energy stored in the capacitor into the flash lamp within a short time and produces the high current and high peak power required for emitting the intense UV flash. The flash frequency was adjusted to one pulse per second. Several types of bacteria were investigated for their susceptibility to pulsed UV illumination. The treated bacterial populations were reduced and determined by direct viable counts. Among the tested bacteria Pseudomonas aeruginosa was the most susceptible to the pulsed UV- light with a 8 log10 cfu/ml reduction after 11 pulses, while the spores of Bacillus megaterium was the most resistant and only 4 log10 cfu/ml reduction achieved after 50 pulses of illumination. The results of this study demonstrated that pulsed UV- light technology could be used as an effective method for the inactivation, of pathogenic bacteria in different environments such as drinking water.

  13. Irrigation of Solanum lycopersicum L. with magnetically treated water increases antioxidant properties of its tomato fruits.

    Science.gov (United States)

    Dubois, A E Ferrer; Leite, G O; Rocha, J B T

    2013-09-01

    Antioxidant effects of tomatoes (Solanum lycopersicum L.) have been studied and an association between dietary intake of tomatoes and lowered risk of cancer, neurodegenerative, and cardiovascular diseases has been suggested. Here we used magnetically treated water (MTW; 0.03-0.15 T), which promotes better germination and productivity in tomatoes, and we investigated the effects of aqueous and ethanolic (10-400 μg/ml) extracts of S. lycopersicum as potential antioxidant against 10 μM Fe(II)-induced thiobarbituric acid reactive species (TBARS) in liver and brain homogenates from rats. The ethanolic extracts from magnetically treated plants were more effective than aqueous extracts in preventing TBARS formation in brain and liver. The protective effects of ethanolic extract can be associated with antioxidants (polyphenols and flavonoids), lycopene and other lipophilic components found in the extract. In effect, magnetically treated plants had higher content of polyphenolic and flavonoid compounds than nontreated plants and they can be a better source of antioxidants than nontreated plants. Consequently, MTW can be used to produce functional foods with high contents of antioxidant components and may have better beneficial health effects than traditionally produced foods.

  14. Growth of Chironomus dilutus larvae exposed to ozone-treated and untreated oil sands process water

    International Nuclear Information System (INIS)

    Anderson, J.; Wiseman, S.; Franz, E.; Jones, P.; Liber, K.; Giesy, J.; Gamal El-Din, M.; Marin, J.

    2010-01-01

    Oil sand processing operations require large quantities of freshwater and produce large volumes of oil sands process water (OSPW) which must be stored on-site. This presentation reviewed various treatment methods for remediating OSPW in order to eliminate downstream toxicity. Naphthenic acids are the most important target fractions for treatment because they are primarily responsible for the acute toxicity of OSPW. Although ozonation has shown promise for reducing OSPW toxicity, the effects of ozonation on aquatic invertebrates remain unknown. This study investigated the effects of exposure to untreated and ozonated OSPW in Chironomus dilutus larvae. OSPW was treated with either a 50 or 80 mg O 3 /L dose of ozonation. The effects of ozonation levels on C. dilutus survival and growth were examined. The study showed that after a 10-day exposure, there were pronounced effects on survival of larvae exposed to ozone-treated or untreated OSPW. Larvae exposed to OSPW were 64-77 percent smaller than their respective controls, but the mean wet mass of organisms exposed to 50 mg O 3 /L ozonated OSPW was not much different from that of the controls. Larvae exposed to 80 mg O 3 /L ozone-treated OSPW were 40 percent smaller than the freshwater controls, and the mean wet mass was also much larger than the untreated OSPW. It was concluded that the toxicity of OSPW to benthic invertebrates may be reduced by ozone treatment.

  15. Growth of Chironomus dilutus larvae exposed to ozone-treated and untreated oil sands process water

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, J.; Wiseman, S.; Franz, E.; Jones, P.; Liber, K.; Giesy, J. [Saskatchewan Univ., Saskatoon, SK (Canada); Gamal El-Din, M.; Marin, J. [Alberta Univ., Edmonton, AB (Canada)

    2010-07-01

    Oil sand processing operations require large quantities of freshwater and produce large volumes of oil sands process water (OSPW) which must be stored on-site. This presentation reviewed various treatment methods for remediating OSPW in order to eliminate downstream toxicity. Naphthenic acids are the most important target fractions for treatment because they are primarily responsible for the acute toxicity of OSPW. Although ozonation has shown promise for reducing OSPW toxicity, the effects of ozonation on aquatic invertebrates remain unknown. This study investigated the effects of exposure to untreated and ozonated OSPW in Chironomus dilutus larvae. OSPW was treated with either a 50 or 80 mg O{sub 3}/L dose of ozonation. The effects of ozonation levels on C. dilutus survival and growth were examined. The study showed that after a 10-day exposure, there were pronounced effects on survival of larvae exposed to ozone-treated or untreated OSPW. Larvae exposed to OSPW were 64-77 percent smaller than their respective controls, but the mean wet mass of organisms exposed to 50 mg O{sub 3}/L ozonated OSPW was not much different from that of the controls. Larvae exposed to 80 mg O{sub 3}/L ozone-treated OSPW were 40 percent smaller than the freshwater controls, and the mean wet mass was also much larger than the untreated OSPW. It was concluded that the toxicity of OSPW to benthic invertebrates may be reduced by ozone treatment.

  16. Controlled cytotoxicity of plasma treated water formulated by open-air hybrid mode discharge

    Science.gov (United States)

    Lu, P.; Boehm, D.; Cullen, P.; Bourke, P.

    2017-06-01

    Plasma treated liquids (PTLs) provide a means to convey a broad range of effects of relevance for food, environmental, or clinical decontamination, plant growth promotion, and therapeutic applications. Devising the reactive species ingredients and controlling the biological response of PTLs are of great interest. We demonstrate an approach by using an open-air hybrid mode discharge (HMD) to control the principal reactive species composition within plasma treated water (PTW), which is then demonstrated to regulate the cytotoxicity of PTW. The cytotoxicity of HMD produced PTW demonstrates a non-monotonic change over the discharge time. Although hydrogen peroxide and nitrite are not the sole effectors for cell death caused by PTW, using them as principal reactive species indicators, cytotoxicity can be removed and/or enhanced by formulating their concentrations and composition through adjusting the discharge mode and time on-line during PTW generation without the addition of additional working gas or chemical scavengers. This work demonstrates that a hybrid mode discharge can be employed to generate a PTW formulation to control a biological response such as cytotoxicity. This provides insights into how plasma treated liquids may be harnessed for biological applications in a specific and controllable manner.

  17. Electric Field-Assisted Photochemical Water Splitting Should Operate with 287 nm Light.

    Science.gov (United States)

    Bachler, Vinzenz; Gärtner, Wolfgang

    2016-05-01

    The major photoreaction of water is the homolytic splitting of one O-H bond starting from the 1(1) B1 excited state (λmax = 167 nm). This reaction produces H• and •OH radicals. The combination of two H• atoms leads to the potential energy carrier dihydrogen. However, the energy required to obtain the photoreactive 1(1) B1 electronic state is about 7.4 eV, which cannot be effectively provided by solar radiation. The sun light spectrum on earth comprises the visible and ultraviolet region, but shows vanishing intensity near 7 eV (177.1 nm). This work provides theoretical evidence that the photoreactive 1(1) B1 state of water can be shifted into the ultraviolet (UV-B) light region (≈287 nm) by including explicitly an electric field in the calculations of the water absorption spectrum. To accomplish such bathochromic shift, a large field strength of 3.08 VÅ(-1) is required. The field-dependent excitation energies were calculated by applying the symmetry-adapted cluster configuration interaction (SAC-CI) procedure. Based on this theoretical analysis, we propose that photochemical water splitting can be accomplished by means of 287 nm light provided the water molecule is favorably oriented by an external electric field and is subsequently activated by a reversal of the field orientation. © 2016 The American Society of Photobiology.

  18. Structural, mechanical and light yield characterisation of heat treated LYSO:Ce single crystals for medical imaging applications

    Energy Technology Data Exchange (ETDEWEB)

    Mengucci, P., E-mail: p.mengucci@univpm.it [Università Politecnica delle Marche, Via Brecce Bianche, 60131 Ancona (Italy); André, G. [Laboratoire Léon Brillouin, CEA-CNRS, CE-Saclay, 91191 Gif sur Yvette cedex (France); Auffray, E. [Department PH-CMX CERN, Route de Meyrin, 1211 Geneva 23 (Switzerland); Barucca, G. [Università Politecnica delle Marche, Via Brecce Bianche, 60131 Ancona (Italy); Cecchi, C. [Dipartimento di Fisica e Geologia, Università di Perugia, Via A. Pascoli, 06123 Perugia (Italy); Chipaux, R. [CEA DSM/IRFU/SEDI, CE-Saclay, 91191 Gif sur Yvette cedex (France); Cousson, A. [Laboratoire Léon Brillouin, CEA-CNRS, CE-Saclay, 91191 Gif sur Yvette cedex (France); Davì, F. [Università Politecnica delle Marche, Via Brecce Bianche, 60131 Ancona (Italy); Di Vara, N. [Department PH-CMX CERN, Route de Meyrin, 1211 Geneva 23 (Switzerland); Rinaldi, D.; Santecchia, E. [Università Politecnica delle Marche, Via Brecce Bianche, 60131 Ancona (Italy)

    2015-06-11

    Five single crystals of cerium-doped lutetium yttrium oxyorthosilicate (LYSO:Ce) grown by the Czochralski method were submitted to structural characterisation by X-ray (XRD) and neutron (ND) diffraction, scanning (SEM) and transmission (TEM) electron microscopy and energy dispersive microanalysis (EDS). The Ultimate Tensile Strength (UTS), the Young Modulus (YM) and the Light Yield (LY) of the samples were also measured in order to correlate the mechanical and the optical behaviour of the crystals with the characteristics of their microstructure. Two of the samples analysed were also heat treated at 300 °C for 10 h to evidence possible variations induced by the temperature in the optical and mechanical response of the crystals. Results showed that the mean compositional variations evidenced by the structural analyses do not affect the mechanical and optical behaviour of the samples. On the contrary, the thermal treatment could induce the formation of coherent spherical particles (size 10 to 15 nm), not uniformly distributed inside the sample, that strongly reduce the UTS and YM values, but it does not affect the optical response of the crystal. This latter result was attributed to the low value of the heating temperature (300 °C) that is not sufficiently high to induce annealing of the oxygen vacancies traps that are responsible of the deterioration of the scintillation properties of the LYSO:Ce crystals. This study was carried out in the framework of the Crystal Clear Collaboration (CCC)

  19. Disinfection of Spacecraft Potable Water Systems by Photocatalytic Oxidation Using UV-A Light Emitting Diodes

    Science.gov (United States)

    Birmele, Michele N.; O'Neal, Jeremy A.; Roberts, Michael S.

    2011-01-01

    Ultraviolet (UV) light has long been used in terrestrial water treatment systems for photodisinfection and the removal of organic compounds by several processes including photoadsorption, photolysis, and photocatalytic oxidation/reduction. Despite its effectiveness for water treatment, UV has not been explored for spacecraft applications because of concerns about the safety and reliability of mercury-containing UV lamps. However, recent advances in ultraviolet light emitting diodes (UV LEDs) have enabled the utilization of nanomaterials that possess the appropriate optical properties for the manufacture of LEDs capable of producing monochromatic light at germicidal wavelengths. This report describes the testing of a commercial-off-the-shelf, high power Nichia UV-A LED (250mW A365nnJ for the excitation of titanium dioxide as a point-of-use (POD) disinfection device in a potable water system. The combination of an immobilized, high surface area photocatalyst with a UV-A LED is promising for potable water system disinfection since toxic chemicals and resupply requirements are reduced. No additional consumables like chemical biocides, absorption columns, or filters are required to disinfect and/or remove potentially toxic disinfectants from the potable water prior to use. Experiments were conducted in a static test stand consisting of a polypropylene microtiter plate containing 3mm glass balls coated with titanium dioxide. Wells filled with water were exposed to ultraviolet light from an actively-cooled UV-A LED positioned above each well and inoculated with six individual challenge microorganisms recovered from the International Space Station (ISS): Burkholderia cepacia, Cupriavidus metallidurans, Methylobacterium fujisawaense, Pseudomonas aeruginosa, Sphingomonas paucimobilis and Wautersia basilensis. Exposure to the Nichia UV-A LED with photocatalytic oxidation resulted in a complete (>7-log) reduction of each challenge bacteria population in <180 minutes of contact

  20. The Effect of Different Perturbations on the Stability Analysis of Light Water Reactors

    International Nuclear Information System (INIS)

    Dykin, Victor

    2010-09-01

    Neutron noise analysis techniques are studied and developed, with primary use of determining the stability of Boiling Water Reactors (BWRs). In particular, the role of a specific perturbation prevailing in Light Water Reactors, the propagating density perturbation, in the stability of BWRs and on the noise field of LWRs in general, is investigated by considering three topics. In the first topics, we investigate how the neutronic response of the reactor, usually described as a second order system driven by a white noise driving force, is affected by a non-white driving force. This latter arises from the reactivity effect of the propagating density perturbations. The investigation is performed by using spectral and correlation analysis. Propagating perturbations with different velocities are analyzed. We investigate how the accuracy of the determination of the so-called decay ratio (DR) of the system, based on the assumption of white noise driving force, deteriorates with deviations from the white noise character of the driving force. In the second topics, the space dependence of the neutron noise, induced by propagating density perturbations, represented through the perturbation of the absorption, is determined and discussed. A full analytical solution was obtained by the use of the Green's function technique. The solution was analyzed for different frequencies and different system sizes. An interesting new interference effect between the point-kinetic and space-dependent components of the induced noise was discovered and interpreted in physical terms. In the last topics, a non-linear stability analysis of a BWR is performed, using so called Reduced Order Model (ROM) techniques. A ROM is usually constructed by reducing the full set of 3D space-time dependent neutron-kinetics, thermal-hydraulics and heat transfer equations to time-dependent ones, by considering space dependence in a lumped parameter model (one or two discrete channels). The main novelty of our work

  1. EFFECTIVENESS OF CHITOSAN AS NATURAL COAGULANT AID IN TREATING TURBID WATERS

    Directory of Open Access Journals (Sweden)

    B. Bina ، M. H. Mehdinejad ، M. Nikaeen ، H. Movahedian Attar

    2009-10-01

    Full Text Available During the last decade, there has been a concern about the relation between aluminum residuals in treated water and Alzheimer disease, and more interest has been considered on the development of natural coagulants such as chitosan. Chitosan, a natural linear biopolyaminosaccharide, is obtained by alkaline deacetylation of chitin. The present study was aimed to investigate the effects of alum as coagulant in conjunction with chitosan as coagulant aid on the removal of turbidity, hardness and Escherichia coli from water. A conventional jar test apparatus was employed for the tests. The optimum pH was observed between 7 to 7.5 for all turbidities. The optimum doses of alum and chitosan when used in conjunction, were 10mg/L and 1mg/L, 5mg/L and 0.5mg/L, and 5mg/L and 0.5mg/L in low, medium and high turbidities, respectively. Turbidity removal efficiency was resulted between %74.3 to %98.2 by alum in conjunction with chitosan. Residual Al+3 in treated water was less than 0.2 mg/L, meeting the international guidelines. The results showed that turbidity decrease provided also a primary Escherichia coli reduction of 2-4 log units within the first 1 to 2 hr of treatment. Hardness removal efficiency decreased when the total hardness increased from 102 to 476mg/L as CaCO3. At low initial turbidity, chitosan showed marginally better performance on hardness, especially at the ranges of 100 to 210 mg/L as CaCO3. In conclusion, coagulant aid showed a useful method for coagulation process. By using natural coagulants, considerable savings in chemicals and sludge handling cost may be achieved.

  2. Assessing the Consistency and Microbiological Effectiveness of Household Water Treatment Practices by Urban and Rural Populations Claiming to Treat Their Water at Home: A Case Study in Peru

    Science.gov (United States)

    Rosa, Ghislaine; Huaylinos, Maria L.; Gil, Ana; Lanata, Claudio; Clasen, Thomas

    2014-01-01

    Background Household water treatment (HWT) can improve drinking water quality and prevent disease if used correctly and consistently by vulnerable populations. Over 1.1 billion people report treating their water prior to drinking it. These estimates, however, are based on responses to household surveys that may exaggerate the consistency and microbiological performance of the practice—key factors for reducing pathogen exposure and achieving health benefits. The objective of this study was to examine how HWT practices are actually performed by households identified as HWT users, according to international monitoring standards. Methods and Findings We conducted a 6-month case study in urban (n = 117 households) and rural (n = 115 households) Peru, a country in which 82.8% of households report treating their water at home. We used direct observation, in-depth interviews, surveys, spot-checks, and water sampling to assess water treatment practices among households that claimed to treat their drinking water at home. While consistency of reported practices was high in both urban (94.8%) and rural (85.3%) settings, availability of treated water (based on self-report) at time of collection was low, with 67.1% and 23.0% of urban and rural households having treated water at all three sampling visits. Self-reported consumption of untreated water in the home among adults and children water of self-reported users was significantly better than source water in the urban setting and negligible but significantly better in the rural setting. However, only 46.3% and 31.6% of households had drinking water water quality. The lack of consistency and sub-optimal microbiological effectiveness also raises questions about the potential of HWT to prevent waterborne diseases. PMID:25522371

  3. The optical properties of greenlandic coastal waters: Modelling light penetration in a changing climate

    DEFF Research Database (Denmark)

    Stedmon, Colin; Markager, S.S.; Pedersen, T.J.

    of these waters. Although solar elevation and sea ice cover play an important role, during the summer month’s light is also regulated by water constituents such as dissolved and particulate organic matter, phytoplankton and suspended sediments. The relative importance of each of these constituents varies...... depending on the influence of shelf water entering the fjords, extent of glacial ice melt and the size and vertical distribution of the phytoplankton biomass. In this study the data from two contrasting sites are compared: Young Sound, a fjord system in Northeast Greenland that imports shelf waters...... with a considerable amount of terrestrial dissolved organic matter (DOM) from the Arctic Ocean; and Godthåbsfjord a fjord in Southwest Greenland where strong tides ensure a regular supply of warm shelf water which melt glacial ice before it can leave the fjord...

  4. Protective structures on the surface of zirconium components of light water reactor cores: Formation, testing, and prototype equipment

    Energy Technology Data Exchange (ETDEWEB)

    Begrambekov, L. B.; Gordeev, A. A.; Evsin, A. E., E-mail: evsin@plasma.mephi.ru; Ivanova, S. V.; Kaplevsky, A. S.; Sadovskiy, Ya. A. [National Research Nuclear University MEPhI (Moscow Engineering Physics Institute) (Russian Federation)

    2015-12-15

    The results of tests of plasma treatment of zirconium and deposition of protective yttrium coatings used as the methods of protection of zirconium components of light water reactor cores against hydrogenation are detailed. The amount of hydrogen in the treated sample exposed to superheated steam for 2500 h at temperature T = 400°C and pressure p = 1 atm was five times lower than the corresponding value for the untreated one. The amount of hydrogen in the sample coated with yttrium remained almost unchanged in 4000 h of exposure. A plasma method for rapid testing for hydrogen resistance is proposed. The hydrogenation rate provided by this method is 700 times higher than that in tests with superheated steam. The results of preliminary experiments confirm the possibility of constructing a unit for batch processing of the surfaces of fuel rod claddings.

  5. Protective structures on the surface of zirconium components of light water reactor cores: Formation, testing, and prototype equipment

    Science.gov (United States)

    Begrambekov, L. B.; Gordeev, A. A.; Evsin, A. E.; Ivanova, S. V.; Kaplevsky, A. S.; Sadovskiy, Ya. A.

    2015-12-01

    The results of tests of plasma treatment of zirconium and deposition of protective yttrium coatings used as the methods of protection of zirconium components of light water reactor cores against hydrogenation are detailed. The amount of hydrogen in the treated sample exposed to superheated steam for 2500 h at temperature T = 400°C and pressure p = 1 atm was five times lower than the corresponding value for the untreated one. The amount of hydrogen in the sample coated with yttrium remained almost unchanged in 4000 h of exposure. A plasma method for rapid testing for hydrogen resistance is proposed. The hydrogenation rate provided by this method is 700 times higher than that in tests with superheated steam. The results of preliminary experiments confirm the possibility of constructing a unit for batch processing of the surfaces of fuel rod claddings.

  6. Light pollution offshore: Zenithal sky glow measurements in the mediterranean coastal waters

    Science.gov (United States)

    Ges, Xavier; Bará, Salvador; García-Gil, Manuel; Zamorano, Jaime; Ribas, Salvador J.; Masana, Eduard

    2018-05-01

    Light pollution is a worldwide phenomenon whose consequences for the natural environment and the human health are being intensively studied nowadays. Most published studies address issues related to light pollution inland. Coastal waters, however, are spaces of high environmental interest, due to their biodiversity richness and their economical significance. The elevated population density in coastal regions is accompanied by correspondingly large emissions of artificial light at night, whose role as an environmental stressor is increasingly being recognized. Characterizing the light pollution levels in coastal waters is a necessary step for protecting these areas. At the same time, the marine surface environment provides a stage free from obstacles for measuring the dependence of the skyglow on the distance to the light polluting sources, and validating (or rejecting) atmospheric light propagation models. In this work we present a proof-of-concept of a gimbal measurement system that can be used for zenithal skyglow measurements on board both small boats and large vessels under actual navigation conditions. We report the results obtained in the summer of 2016 along two measurement routes in the Mediterranean waters offshore Barcelona, travelling 9 and 31.7 km away from the coast. The atmospheric conditions in both routes were different from the ones assumed for the calculation of recently published models of the anthropogenic sky brightness. They were closer in the first route, whose results approach better the theoretical predictions. The results obtained in the second route, conducted under a clearer atmosphere, showed systematic differences that can be traced back to two expected phenomena, which are a consequence of the smaller aerosol content: the reduction of the anthropogenic sky glow at short distances from the sources, and the slower decay rate of brightness with distance, which gives rise to a relative excess of brightness at large distances from the

  7. Seasonal ammonia losses from spray-irrigation with secondary-treated recycled water.

    Science.gov (United States)

    Saez, Jose A; Harmon, Thomas C; Doshi, Sarika; Guerrero, Francisco

    2012-01-01

    This work examines ammonia volatilization associated with agricultural irrigation employing recycled water. Effluent from a secondary wastewater treatment plant was applied using a center pivot irrigation system on a 12 ha agricultural site in Palmdale, California. Irrigation water was captured in shallow pans and ammonia concentrations were quantified in four seasonal events. The average ammonia loss ranged from 15 to 35% (averaging 22%) over 2-h periods. Temporal mass losses were well-fit using a first-order model. The resulting rate constants correlated primarily with temperature and secondarily with wind speed. The observed application rates and timing were projected over an entire irrigation season using meteorological time series data from the site, which yielded volatilization estimates of 0.03 to 0.09 metric tons NH(3)-N/ha per year. These rates are consistent with average rates (0.04 to 0.08 MT NH(3)-N/ha per year) based on 10 to 20 mg NH(3)-N/L effluent concentrations and a 22% average removal. As less than 10% of the treated effluent in California is currently reused, there is potential for this source to increase, but the increase may be offset by a corresponding reduction in synthetic fertilizers usage. This point is a factor for consideration with respect to nutrient management using recycled water.

  8. Photodegradation kinetics and transformation products of ketoprofen, diclofenac and atenolol in pure water and treated wastewater

    International Nuclear Information System (INIS)

    Salgado, R.; Pereira, V.J.; Carvalho, G.; Soeiro, R.; Gaffney, V.; Almeida, C.; Cardoso, V. Vale; Ferreira, E.; Benoliel, M.J.

    2013-01-01

    Highlights: ► Direct UV photolysis of 3 pharmaceuticals in pure and waste water was investigated. ► Ketoprofen has higher photodegradion kinetics, followed by diclofenac and atenolol. ► MP/UV photodegradation products were identified for the 3 compounds. ► Photodegradation pathways were proposed to explain the obtained products. ► The persistent photoproducts were identified for each compound. -- Abstract: Pharmaceutical compounds such as ketoprofen, diclofenac and atenolol are frequently detected at relatively high concentrations in secondary effluents from wastewater treatment plants. Therefore, it is important to assess their transformation kinetics and intermediates in subsequent disinfection processes, such as direct ultraviolet (UV) irradiation. The photodegradation kinetics of these compounds using a medium pressure (MP) lamp was assessed in pure water, as well as in filtered and unfiltered treated wastewater. Ketoprofen had the highest time- and fluence-based rate constants in all experiments, whereas atenolol had the lowest values, which is consistent with the corresponding decadic molar absorption coefficient and quantum yield. The fluence-based rate constants of all compounds were evaluated in filtered and unfiltered wastewater matrices as well as in pure water. Furthermore, transformation products of ketoprofen, diclofenac and atenolol were identified and monitored throughout the irradiation experiments, and photodegradation pathways were proposed for each compound. This enabled the identification of persistent transformation products, which are potentially discharged from WWTP disinfection works employing UV photolysis

  9. Photodegradation kinetics and transformation products of ketoprofen, diclofenac and atenolol in pure water and treated wastewater

    Energy Technology Data Exchange (ETDEWEB)

    Salgado, R. [REQUIMTE/CQFB, Chemistry Department, FCT, Universidade Nova de Lisboa, 2829-516 Caparica (Portugal); ESTS-IPS, Escola Superior de Tecnologia de Setúbal do Instituto Politécnico de Setúbal, Rua Vale de Chaves, Campus do IPS, Estefanilha, 2910-761 Setúbal (Portugal); Pereira, V.J. [Instituto de Biologia Experimental e Tecnológica (IBET), Av. da República (EAN), 2784-505 Oeiras (Portugal); Instituto de Tecnologia Química e Biológica (ITQB) – Universidade Nova de Lisboa (UNL), Av. da República, Estação Agronómica Nacional, 2780-157 Oeiras, 5 Portugal (Portugal); Carvalho, G., E-mail: gs.carvalho@fct.unl.pt [REQUIMTE/CQFB, Chemistry Department, FCT, Universidade Nova de Lisboa, 2829-516 Caparica (Portugal); Instituto de Biologia Experimental e Tecnológica (IBET), Av. da República (EAN), 2784-505 Oeiras (Portugal); Soeiro, R. [REQUIMTE/CQFB, Chemistry Department, FCT, Universidade Nova de Lisboa, 2829-516 Caparica (Portugal); Gaffney, V.; Almeida, C. [Institute for Medicines and Pharmaceutical Sciences (iMed.UL), Faculdade de Farmácia da Universidade de Lisboa (FFUL), Av. Prof. Gama Pinto, 1600-049 Lisboa (Portugal); Cardoso, V. Vale; Ferreira, E.; Benoliel, M.J. [Empresa Portuguesa das Águas Livres, S.A., Direcção de Controlo de Qualidade da Água, Laboratório Central, Avenida de Berlim, 15, 1800-031 Lisboa (Portugal); and others

    2013-01-15

    Highlights: ► Direct UV photolysis of 3 pharmaceuticals in pure and waste water was investigated. ► Ketoprofen has higher photodegradion kinetics, followed by diclofenac and atenolol. ► MP/UV photodegradation products were identified for the 3 compounds. ► Photodegradation pathways were proposed to explain the obtained products. ► The persistent photoproducts were identified for each compound. -- Abstract: Pharmaceutical compounds such as ketoprofen, diclofenac and atenolol are frequently detected at relatively high concentrations in secondary effluents from wastewater treatment plants. Therefore, it is important to assess their transformation kinetics and intermediates in subsequent disinfection processes, such as direct ultraviolet (UV) irradiation. The photodegradation kinetics of these compounds using a medium pressure (MP) lamp was assessed in pure water, as well as in filtered and unfiltered treated wastewater. Ketoprofen had the highest time- and fluence-based rate constants in all experiments, whereas atenolol had the lowest values, which is consistent with the corresponding decadic molar absorption coefficient and quantum yield. The fluence-based rate constants of all compounds were evaluated in filtered and unfiltered wastewater matrices as well as in pure water. Furthermore, transformation products of ketoprofen, diclofenac and atenolol were identified and monitored throughout the irradiation experiments, and photodegradation pathways were proposed for each compound. This enabled the identification of persistent transformation products, which are potentially discharged from WWTP disinfection works employing UV photolysis.

  10. Cleaning oil refining drainage waters out of emulsified oil products with thermic treated cedar nut shell

    Science.gov (United States)

    Pyatanova, P. A.; Adeeva, L. N.

    2017-08-01

    It was elaborated the ability of the sorbent produced by thermic treatment of cedar nut shell to destruct model and real first kind (direct) emulsions in static and dynamic conditions. In static conditions optimal ratio sorbent-emulsion with the original concentration of oil products 800 mg/l was in the range of 2.0 g per 100 ml of emulsion which corresponds to the level of treatment 94.9%. The time of emulsion destruction was 40 minutes. This sorbent is highly active in dynamic processes of oil-contaminated water treatment, the level of treatment 96.0% is being achieved. Full dynamic sorptive capacity of the sorbent is 0.85 g/g. Sorbent based on the thermic treated cedar nut shell can be elaborated as sorptive filter element of local treatment facilities of oil refining and petrochemical processes. After the treatment with this sorbent of drainage waters of oil refinery in dynamic conditions the concentration of oil products became less than mpc on oil products for waste waters coming to biological treatment.

  11. Superposition method used for treating oilfield interference in Iranian water-drive reservoir

    Energy Technology Data Exchange (ETDEWEB)

    Hamid, K. [National Iranian South Oil Company, (Iran, Islamic Republic of)

    2003-07-01

    Water-drive oil fields that share a common aquifer are in hydrodynamic communication. Production from such fields is accompanied by pressure loss that manifests itself as pressure interference because the decline in pressure is transmitted through the aquifer to other fields even several miles away from a producing pool. In order to address the challenge of discovering new Iranian oil reserves, attention has focused on the efficient development of existing reservoirs. The Asmari reservoir consists of a high permeability sand and carbonate section in an elongated anticlinal structure. A drop in reservoir pressure was observed in field 'A' in 1974. This drop in pressure was noted one year after field 'B' in the same reservoir reached peak oil production of 1.1 MMBPD. A practical analytical method was developed to help the reservoir engineer analyze oilfield interference problems. Reservoir performance indicates that the aquifer from field 'A' has strong communication with field 'B'. The most practical method for treating oilfield interference in water-drive Iranian reservoirs was the superposition technique. It was emphasized that the impact of nearby fields should be considered in all reservoir simulations to accurately identify regional aquifer effects on flow rates and oil-water contact movement. 13 refs., 2 tabs., 4 figs.

  12. The application of ceramic membranes for treating effluent water from closed-circuit fish farming

    Directory of Open Access Journals (Sweden)

    Bonisławska Małgorzata

    2016-06-01

    Full Text Available The aim of the study was to analyze and assess the possibility of using a two-stage filtration system with ceramic membranes: a 3-tube module with 1.0 kDa cut-off (1st stage and a one-tube module with 0.45 kDa cut-off (2nd stage for treating effluent water from a juvenile African catfish aquaculture. The study revealed that during the 1st filtration stage of the effluent water, the highest degrees of retention were obtained with respect to: suspended solids SS (rejection coefficient RI=100%, turbidity (RI=99.40%, total iron (RI=89.20%, BOD5 (RI=76.0%, nitrite nitrogen (RI=62.30%, and CODCr (RI=41.74%. The 2nd filtration stage resulted in a lower reduction degree of the tested indicators in comparison to the 1st filtration stage. At the 2nd stage, the highest values of the rejection coefficient were noted in for the total iron content (RIV=100%, CODCr (RIV=59.52%; RV=64.28%, RVI=63.49% and turbidity (RIV and RV = 45.0%, RVI=50.0%. The obtained results indicate that ceramic membranes (with 1.0 and 0.45 kDa cut-offs may be used in recirculation aquaculture systems as one of the stages of effluent water treatment.

  13. Microbial pathogens in source and treated waters from drinking water treatment plants in the United States and implications for human health

    Data.gov (United States)

    U.S. Environmental Protection Agency — Bacteria and fungi in source and treated drinking water. This dataset is associated with the following publication: King , D., S. Pfaller , M. Donohue , S. Vesper ,...

  14. 78 FR 41436 - Proposed Revision to Treatment of Non-Safety Systems for Passive Advanced Light Water Reactors

    Science.gov (United States)

    2013-07-10

    ..., ``Regulatory Treatment of Non- Safety Systems (RTNSS) for Passive Advanced Light Water Reactors.'' This area... NUCLEAR REGULATORY COMMISSION [NRC-2013-0150] Proposed Revision to Treatment of Non-Safety Systems for Passive Advanced Light Water Reactors AGENCY: Nuclear Regulatory Commission. ACTION: Standard...

  15. Low-intensity blue-enriched white light (750 lux and standard bright light (10 000 lux are equally effective in treating SAD. A randomized controlled study

    Directory of Open Access Journals (Sweden)

    Bos Elske H

    2011-01-01

    Full Text Available Abstract Background Photoreceptor cells containing melanopsin play a role in the phase-shifting effects of short-wavelength light. In a previous study, we compared the standard light treatment (SLT of SAD with treatment using short-wavelength blue-enriched white light (BLT. Both treatments used the same illuminance (10 000 lux and were equally highly effective. It is still possible, however, that neither the newly-discovered photoreceptor cells, nor the biological clock play a major role in the therapeutic effects of light on SAD. Alternatively, these effects may at least be partly mediated by these receptor cells, which may have become saturated as a result of the high illuminances used in the therapy. This randomized controlled study compares the effects of low-intensity BLT to those of high-intensity SLT. Method In a 22-day design, 22 patients suffering from a major depression with a seasonal pattern (SAD were given light treatment (10 000 lux for two weeks on workdays. Subjects were randomly assigned to either of the two conditions, with gender and age evenly distributed over the groups. Light treatment either consisted of 30 minutes SLT (5000°K with the EnergyLight® (Philips, Consumer Lifestyle with a vertical illuminance of 10 000 lux at eye position or BLT (17 000°K with a vertical illuminance of 750 lux using a prototype of the EnergyLight® which emitted a higher proportion of short-wavelengths. All participants completed questionnaires concerning mood, activation and sleep quality on a daily basis. Mood and energy levels were also assessed on a weekly basis by means of the SIGH-SAD and other assessment tools. Results On day 22, SIGH-SAD ratings were significantly lower than on day 1 (SLT 65.2% and BLT 76.4%. On the basis of all assessments no statistically significant differences were found between the two conditions. Conclusion With sample size being small, conclusions can only be preliminary. Both treatment conditions were found

  16. Low-intensity blue-enriched white light (750 lux) and standard bright light (10,000 lux) are equally effective in treating SAD. A randomized controlled study.

    Science.gov (United States)

    Meesters, Ybe; Dekker, Vera; Schlangen, Luc J M; Bos, Elske H; Ruiter, Martine J

    2011-01-28

    Photoreceptor cells containing melanopsin play a role in the phase-shifting effects of short-wavelength light. In a previous study, we compared the standard light treatment (SLT) of SAD with treatment using short-wavelength blue-enriched white light (BLT). Both treatments used the same illuminance (10,000 lux) and were equally highly effective. It is still possible, however, that neither the newly-discovered photoreceptor cells, nor the biological clock play a major role in the therapeutic effects of light on SAD. Alternatively, these effects may at least be partly mediated by these receptor cells, which may have become saturated as a result of the high illuminances used in the therapy. This randomized controlled study compares the effects of low-intensity BLT to those of high-intensity SLT. In a 22-day design, 22 patients suffering from a major depression with a seasonal pattern (SAD) were given light treatment (10,000 lux) for two weeks on workdays. Subjects were randomly assigned to either of the two conditions, with gender and age evenly distributed over the groups. Light treatment either consisted of 30 minutes SLT (5000 °K) with the EnergyLight® (Philips, Consumer Lifestyle) with a vertical illuminance of 10,000 lux at eye position or BLT (17,000 °K) with a vertical illuminance of 750 lux using a prototype of the EnergyLight® which emitted a higher proportion of short-wavelengths. All participants completed questionnaires concerning mood, activation and sleep quality on a daily basis. Mood and energy levels were also assessed on a weekly basis by means of the SIGH-SAD and other assessment tools. On day 22, SIGH-SAD ratings were significantly lower than on day 1 (SLT 65.2% and BLT 76.4%). On the basis of all assessments no statistically significant differences were found between the two conditions. With sample size being small, conclusions can only be preliminary. Both treatment conditions were found to be highly effective. The therapeutic effects of low

  17. Stress analysis of the reactor pressure vessel of the high performance light water reactors (HPLWR); Festigkeitsanalyse fuer den Reaktordruckbehaelter des High Performance Light Water Reactor (HPLWR)

    Energy Technology Data Exchange (ETDEWEB)

    Guelton, E.; Fischer, K.

    2006-12-15

    The High Performance Light Water Reactor (HPLWR) is one of the concepts of the Generation IV program. The main difference compared to current Light Water Reactors (LWR) results from the supercritical steam condition of the coolant. Due to the supercritical pressure of 25 MPa, water, used as moderator and coolant, flows as a single phase through the core. The temperatures at the outlet are above 500 C. These conditions have a major impact on the design of the Reactor Pressure Vessel (RPV). For the modelling a RPV concept is proposed, which resembles the design of current LWR and allows the use of approved materials on one side and also meets the additional demands on the other side. A first dimensioning of the RPV wall thicknesses and the geometrical proportions has been performed using the german KTA-guidelines. To verify these results, a stress analysis using the finite element method has been performed with the program ANSYS. The combined mechanical and thermal calculations provide the primary, secondary and peak stresses which are evaluated using the KTA-guidelines design loading (Level 0) and service loading level A for the different components. The results confirm the wall thicknesses estimated by Fischer et al. (2006), but there are peak stresses in the vicinity of the inlet and outlet flanges, which are very close to the allowed design limit. For larger diameters of the RPV those regions will become critical and the stresses might exceed the design limits. Design optimizations for those regions are proposed and evaluated. A readjusted geometry of the inlet flange reduces those stresses by 65%. (orig.)

  18. Safety analysis of a high temperature supercritical pressure light water cooled and moderated reactor

    International Nuclear Information System (INIS)

    Ishiwatari, Y.; Oka, Y.; Koshizuka, S.

    2002-01-01

    A safety analysis code for a high temperature supercritical pressure light water cooled reactor (SCLWR-H) with water rods cooled by descending flow, SPRAT-DOWN, is developed. The hottest channel, a water rod, down comer, upper and lower plenums, feed pumps, etc. are modeled as junction of nodes. Partial of the feed water flows downward from the upper dome of the reactor pressure vessel to the water rods. The accidents analyzed here are total loss of feed water flow, feed water pump seizure, and control rods ejection. All the accidents satisfy the criteria. The accident event at which the maximum cladding temperature is the highest is total loss of feedwater flow. The transients analyzed here are loss of feed water heating, inadvertent start-up of an auxiliary water supply system, partial loss of feed water flow, loss of offsite power, loss of load, and abnormal withdrawal of control rods. All the transients satisfied the criteria. The transient event for which the maximum cladding temperature is the highest is control rod withdrawal at normal operation. The behavior of loss of load transient is different from that of BWR. The power does not increase because loss of flow occurs and the density change is small. The sensitivities of the system behavior to various parameters during transients and accidents are analyzed. The parameters having strong influence are the capacity of the auxiliary water supply system, the coast down time of the main feed water pumps, and the time delay of the main feed water pumps trip. The control rod reactivity also has strong influence. (authors)

  19. Treating Coalbed Natural Gas Produced Water for Beneficial Use By MFI Zeolite Membranes

    Energy Technology Data Exchange (ETDEWEB)

    Robert Lee; Liangxiong Li

    2008-03-31

    Desalination of brines produced from oil and gas fields is an attractive option for providing potable water in arid regions. Recent field-testing of subsurface sequestration of carbon dioxide for climate management purposes provides new motivation for optimizing efficacy of oilfield brine desalination: as subsurface reservoirs become used for storing CO{sub 2}, the displaced brines must be managed somehow. However, oilfield brine desalination is not economical at this time because of high costs of synthesizing membranes and the need for sophisticated pretreatments to reduce initial high TDS and to prevent serious fouling of membranes. In addition to these barriers, oil/gas field brines typically contain high concentrations of multivalent counter cations (eg. Ca{sup 2+} and SO{sub 4}{sup 2-}) that can reduce efficacy of reverse osmosis (RO). Development of inorganic membranes with typical characteristics of high strength and stability provide a valuable option to clean produced water for beneficial uses. Zeolite membranes have a well-defined subnanometer pore structure and extreme chemical and mechanical stability, thus showing promising applicability in produced water purification. For example, the MFI-type zeolite membranes with uniform pore size of {approx}0.56 nm can separate ions from aqueous solution through a mechanism of size exclusion and electrostatic repulsion (Donnan exclusion). Such a combination allows zeolite membranes to be unique in separation of both organics and electrolytes from aqueous solutions by a reverse osmosis process, which is of great interest for difficult separations, such as oil-containing produced water purification. The objectives of the project 'Treating Coalbed Natural Gas Produced Water for Beneficial Use by MFI Zeolite Membranes' are: (1) to conduct extensive fundamental investigations and understand the mechanism of the RO process on zeolite membranes and factors determining the membrane performance, (2) to improve

  20. STATIC BENDING STRENGHT OF WOOD TREATED WITH FIRE RETERDANT AND WATER REPELLENT PRESERVATION CHEMICALS

    Directory of Open Access Journals (Sweden)

    Hüseyin PEKER

    1999-01-01

    Full Text Available This study has designed for determination of static bending strenght of mainly boron impregnated scots pine and east beech wood. Other chemicals used as control are polyethylene glycole (PEG-400 and some commercial preservatives such as Vacsol (V, Ammonıum sulphate (AS and Diammonium phospate (DAP were used by secondary process on the boron or PEG treated wood by the aim of improving static bending strenght and avoiding the leachability of both chemicals. Result indicated that static bending strenght of scots pine wood were reduced by acidic solutions of salts. In beech wood static bending strenght were also affected by neutral pH of the solution. Water repellent , surprisingly don't show their aspected protective properties of static bending strength, in general .

  1. Removal of turbidity, COD and BOD from secondarily treated sewage water by electrolytic treatment

    Science.gov (United States)

    Chopra, Ashok Kumar; Sharma, Arun Kumar

    2013-03-01

    A preliminary study was conducted for the removal of turbidity (TD), chemical oxygen demand (COD) and biochemical oxygen demand (BOD) from secondarily treated sewage (STS) water through the electrolytic batch mode experiments with DC power supply (12 V) up to 30 min and using a novel concept of electrode combinations of different metals. The different surface areas (40, 80, 120 and 160 cm2) of the electrodes as a function of cross-sectional area of the reactor and the effect of inter-electrode distances (2.5-10 cm) on the electrolysis of STS water were studied. This study revealed that the effluent can be effectively treated with the aluminum (Al) and iron (Fe) electrode combinations (Al-Fe and Fe-Al). The maximum removal of TD (81.51 %), COD (74.36 %) and BOD (70.86 %) was recorded with Al-Fe electrode system, while the removal of these parameters was found to be 71.11, 64.95 and 61.87 %, respectively, with Fe-Al electrode combination. The Al-Fe electrode combination had lower electrical energy consumption (2.29 kWh/m3) as compared to Fe-Al electrode combination (2.50 kWh/m3). The economic evaluation of electrodes showed that Al-Fe electrode combination was better than Fe-Al electrode combination. This revealed the superiority of aluminum as a sacrificial electrode over that of iron which can probably be attributed to better flocculation capabilities of aluminum than that of iron.

  2. Treating ammonium-rich wastewater with sludge from water treatment plant to produce ammonium alum

    Directory of Open Access Journals (Sweden)

    Wen-Po Cheng

    2016-03-01

    Full Text Available This study applies a process to treat ammonium-rich wastewater using alum-generated sludge form water purification plant, and gain economic benefit by producing ammonium alum (Al(NH4(SO42·12H2O. The factors affecting production of ammonium alum include molar ratio of ammonium to aluminum concentration, sulfuric acid concentration, mixing speed, mixing time, standing time, and temperature. According to the equation for the ammonium removal reaction, the theoretical quantity of ammonium alum was calculated based on initial and final concentrations of ammonium. Then, the weight of ammonium alum crystal was divided by the theoretical weight to derive the recovery ratio. The optimum sludge and sulfuric acid dosage to treat about 17 g L−1 ammonium wastewater are 300 g L−1 and 100 mL L−1, respectively. The optimal dosage for wastewater is molar ratio of ammonium to aluminum of about 1 due to the aluminum dissolving in acidified wastewater. The ammonium removal efficiency is roughly 70% and the maximum recovery ratio for ammonium alum is 93% when the wastewater is mixed for 10 min at the mixing velocity gradient of 100 s−1. Ammonium alum production or ammonium removal can be enhanced by controlling the reaction at low temperatures.

  3. Chlorinated and ultraviolet radiation -treated reclaimed irrigation water is the source of Aeromonas found in vegetables used for human consumption

    International Nuclear Information System (INIS)

    Latif-Eugenín, Fadua; Beaz-Hidalgo, Roxana; Silvera-Simón, Carolina; Fernandez-Cassi, Xavi; Figueras, María J.

    2017-01-01

    Wastewater is increasingly being recognized as a key water resource, and reclaimed water (or treated wastewater) is used for irrigating vegetables destined for human consumption. The aim of the present study was to determine the diversity and prevalence of Aeromonas spp. both in reclaimed water used for irrigation and in the three types of vegetables irrigated with that water. Seven of the 11 (63.6%) samples of reclaimed water and all samples of vegetables were positive for the presence of Aeromonas. A total of 216 Aeromonas isolates were genotyped and corresponded to 132 different strains that after identification by sequencing the rpoD gene belonged to 10 different species. The prevalence of the species varied depending on the type of sample. In the secondary treated reclaimed water A. caviae and A. media dominated (91.4%) while A. salmonicida, A. media, A. allosaccharophila and A. popoffii represented 74.0% of the strains in the irrigation water. In vegetables, A. caviae (75.0%) was the most common species, among which a strain isolated from lettuce had the same genotype (ERIC pattern) as a strain recovered from the irrigation water. Furthermore, the same genotype of the species A. sanarellii was recovered from parsley and tomatoes demonstrating that irrigation water was the source of contamination and confirming the risk for public health. - Highlights: • Reclaimed water (= treated wastewater) is used for the irrigation of vegetables. • Aeromonas was found in reclaimed water and irrigated vegetables with this water. • The prevalence of Aeromonas spp. varied between irrigation water and vegetables. • Epidemiological relationships were found between irrigation water and vegetables. • The water was the source of contamination which means a risk for the public health.

  4. Modeling the electrochemistry of the primary circuits of light water reactors

    International Nuclear Information System (INIS)

    Bertuch, A.; Macdonald, D.D.; Pang, J.; Kriksunov, L.; Arioka, K.

    1994-01-01

    To model the corrosion behaviors of the heat transport circuits of light water reactors, a mixed potential model (NTM) has been developed and applied to both boiling water reactors (BWRs) and pressurized water reactors (PWRs). Using the data generated by the GE/UKEA-Harwell radiolysis model, electrochemical potentials (ECPs) have been calculated for the heat transport circuits of eight BWRs operating under hydrogen water chemistry (HWC). By modeling the corrosion behaviors of these reactors, the effectiveness of HWC at limiting IGSCC and IASCC can be determined. For simulating PWR primary circuits, a chemical-radiolysis model (developed by the authors) was used to generate input parameters for the MPM. Corrosion potentials of Type 304 and 316 SSs in PWR primary environments were calculated using the NTM and were found to be in good agreement with the corrosion potentials measured in the laboratory for simulated PWR primary environments

  5. 111 oriented gold nanoplatelets on multilayer graphene as visible light photocatalyst for overall water splitting

    Science.gov (United States)

    Mateo, Diego; Esteve-Adell, Iván; Albero, Josep; Royo, Juan F. Sánchez; Primo, Ana; Garcia, Hermenegildo

    2016-06-01

    Development of renewable fuels from solar light appears as one of the main current challenges in energy science. A plethora of photocatalysts have been investigated to obtain hydrogen and oxygen from water and solar light in the last decades. However, the photon-to-hydrogen molecule conversion is still far from allowing real implementation of solar fuels. Here we show that 111 facet-oriented gold nanoplatelets on multilayer graphene films deposited on quartz is a highly active photocatalyst for simulated sunlight overall water splitting into hydrogen and oxygen in the absence of sacrificial electron donors, achieving hydrogen production rate of 1.2 molH2 per gcomposite per h. This photocatalytic activity arises from the gold preferential orientation and the strong gold-graphene interaction occurring in the composite system.

  6. Interaction between licensing and light water reactor research in the Federal Republic of Germany

    International Nuclear Information System (INIS)

    Jahns, A.

    1977-01-01

    The organization of the licensing procedure for nuclear power plants and of the light water reactor safety research in the Federal Republic of Germany will be described. Special emphasis will be given to the role of the Reactor Safety Committee (RSK). The well organized interacting process between regulatory authorities, licensing review bodies, applicants and system vendors assures that the safety problems arising from the use of nuclear energy have been solved during the licensing procedure. Where uncertainties on partial phenomena had to be bridged by conservative assumptions, it is--among others--the goal of the extensive safety research program to improve the understanding of those phenomena and quantify the safety margins. Experience with the operation of light water reactors has shown that the methods of reactor safety have proved to be satisfactory

  7. Evaluation and improvement in nondestructive examination (NDE) reliability for inservice inspection of light water reactors

    International Nuclear Information System (INIS)

    Doctor, S.R.; Deffenbaugh, J.D.; Good, M.S.; Green, E.R.; Heasler, P.G.; Simonen, F.A.; Spanner, J.C.; Taylor, T.T.

    1988-01-01

    The Evaluation and Improvement of NDE Reliability for Inservice Inspection of Light Water Reactors (NDE Reliability) program at the Pacific Northwest Laboratory was established by the NRC to determine the reliability of current inservice inspection (ISI) techniques and to develop recommendations that will ensure a suitably high inspection reliability. The objectives of this program include determining the reliability of ISI performed on the primary systems of commercial light-water reactors (LWRs); using probabilistic fracture mechanics analysis to determine the impact of NDE unreliability on system safety; and evaluating reliability improvements that can be achieved with improved and advanced technology. A final objective is to formulate recommended revisions to ASME Code and Regulatory requirements, based on material properties, service conditions and NDE uncertainties. The program scope is limited to ISI of the primary systems including the piping, vessel, and other inspected components. This is a progress report covering the programmatic work from October 1986 through September 1987. (author)

  8. International academic program in technologies of light-water nuclear reactors. Phases of development and implementation

    International Nuclear Information System (INIS)

    Geraskin, N I; Glebov, V B

    2017-01-01

    The results of implementation of European educational projects CORONA and CORONA II dedicated to preserving and further developing nuclear knowledge and competencies in the area of technologies of light-water nuclear reactors are analyzed. Present article addresses issues of design and implementation of the program for specialized training in the branch of technologies of light-water nuclear reactors. The systematic approach has been used to construct the program for students of nuclear specialties, which corresponding to IAEA standards and commonly accepted nuclear principles recognized in the European Union. Possibilities of further development of the international cooperation between countries and educational institutions are analyzed. Special attention is paid to e-learning/distance training, nuclear knowledge preservation and interaction with European Nuclear Education Network. (paper)

  9. Removal of Nerve Agent Simulants from Water Using Light-Responsive Molecular Baskets.

    Science.gov (United States)

    Border, Sarah E; Pavlović, Radoslav Z; Zhiquan, Lei; Badjić, Jovica D

    2017-12-27

    We found that molecular baskets 1-3, with amino acids at their rim, undergo photoinduced decarboxylations to give baskets 4-6 forming a solid precipitate in water. Furthermore, organophosphonates 7-9 (OP), akin in size and shape to G-type nerve agents, form inclusion complexes with baskets 1-3 (K = 6-2243 M -1 ). Light irradiation (300 nm) of an aqueous solution of 1-3⊂OP led to the formation of precipitate containing an OP compound thereby amounting to a novel strategy for light-induced sequestration of nerve agents or, perhaps, other targeted compounds. Importantly, the stability of basket⊂OP complexes in addition to functional groups at the basket's rim play a role in the efficiency (up to 98%) by which OPs are removed from water.

  10. International academic program in technologies of light-water nuclear reactors. Phases of development and implementation

    Science.gov (United States)

    Geraskin, N. I.; Glebov, V. B.

    2017-01-01

    The results of implementation of European educational projects CORONA and CORONA II dedicated to preserving and further developing nuclear knowledge and competencies in the area of technologies of light-water nuclear reactors are analyzed. Present article addresses issues of design and implementation of the program for specialized training in the branch of technologies of light-water nuclear reactors. The systematic approach has been used to construct the program for students of nuclear specialties, which corresponding to IAEA standards and commonly accepted nuclear principles recognized in the European Union. Possibilities of further development of the international cooperation between countries and educational institutions are analyzed. Special attention is paid to e-learning/distance training, nuclear knowledge preservation and interaction with European Nuclear Education Network.

  11. Radioactivity, radiation protection and monitoring during dismantling of light-water reactors

    International Nuclear Information System (INIS)

    Hummel, L.; Zech, J.B.

    2005-01-01

    Based on the radioactivity inventory in the systems and components of light-water reactors observed during operation, the impact of actions during plant emptying after the conclusion of power operation and possible subsequent long-term safe enclosure concerning the composition of the nuclide inventory of the plant to be dismantled will be described. Derived from this will be the effects on radioactivity monitoring in the plant, physical radiation protection monitoring, and the measured characterization of the residual materials resulting from the dismantling. The impact of long-term interim storage will also be addressed in the discussion. The talk should provide an overview of the interrelationships between source terms, decay times and the radioactivity monitoring requirements of the various dismantling concepts for commercial light-water reactors. (orig.)

  12. Technical specification: Mixed-oxide pellets for the light-water reactor irradiation demonstration test

    International Nuclear Information System (INIS)

    Cowell, B.S.

    1997-06-01

    This technical specification is a Level 2 Document as defined in the Fissile Materials Disposition Program Light-Water Reactor Mixed-oxide Fuel Irradiation Test Project Plan. It is patterned after the pellet specification that was prepared by Atomic Energy of Canada, Limited, for use by Los Alamos National Laboratory in fabrication of the test fuel for the Parallex Project, adjusted as necessary to reflect the differences between the Canadian uranium-deuterium reactor and light-water reactor fuels. This specification and the associated engineering drawing are to be utilized only for preparation of test fuel as outlined in the accompanying Request for Quotation and for additional testing as directed by Oak Ridge National Laboratory or the Department of Energy

  13. Meeting Summary Advanced Light Water Reactor Fuels Industry Meeting Washington DC October 27 - 28, 2011

    Energy Technology Data Exchange (ETDEWEB)

    Not Listed

    2011-11-01

    The Advanced LWR Fuel Working Group first met in November of 2010 with the objective of looking 20 years ahead to the role that advanced fuels could play in improving light water reactor technology, such as waste reduction and economics. When the group met again in March 2011, the Fukushima incident was still unfolding. After the March meeting, the focus of the program changed to determining what we could do in the near term to improve fuel accident tolerance. Any discussion of fuels with enhanced accident tolerance will likely need to consider an advanced light water reactor with enhanced accident tolerance, along with the fuel. The Advanced LWR Fuel Working Group met in Washington D.C. on October 72-18, 2011 to continue discussions on this important topic.

  14. Evaluation and improvement in nondestructive examination (NDE) reliability for inservice inspection of light water reactors

    International Nuclear Information System (INIS)

    Doctor, S.R.; Deffenbaugh, J.D.; Good, M.S.; Green, E.R.; Heasler, P.G.; Simonen, F.A.; Spanner, J.C.; Taylor, T.T.

    1988-01-01

    The Evaluation and Improvement of NDE Reliability for Inservice Inspection of Light Water Reactor (NDE Reliability) program at the Pacific Northwest Laboratory was established by the NRC to determine the reliability of current inservice inspection (ISI) techniques and to develop recommendations that will ensure a suitably high inspection reliability. The objectives of this program include determining the reliability of ISI performed on the primary systems of commercial light-water reactors (LWRs); using probabilistic fracture mechanics analysis to determine the impact of NDE unreliability on system safety; and evaluating reliability improvements that can be achieved with improved and advanced technology. A final objective is to formulate recommended revisions to ASME Code and Regulatory requirements, based on material properties, service conditions, and NDE uncertainties. The program scope is limited to ISI of the primary systems including the piping, vessel, and other inspected components. This is a progress report covering the programmatic work from October 1986 through September 1987

  15. Contribution to the interpretation of explosive phenomena in research light-water reactors

    International Nuclear Information System (INIS)

    Le Berre, Francois.

    1975-08-01

    The study allows the prediction of the transient behavior of a light-water reactor that undergoes a power excursion due to a step reactivity insertion. In particular, a film-model for boiling is developed, which takes into account fast heat transfers, and permits the description of the water-hammer phenomena. The latter is due to the sudden contact between the liquid coolant and the fuel plates, which results from the vanishing of the vapor film. It is shown in which conditions this phenomena may initiate a reactor explosion [fr

  16. DOE/NNSA perspective safeguard by design: GEN III/III+ light water reactors and beyond

    Energy Technology Data Exchange (ETDEWEB)

    Pan, Paul Y [Los Alamos National Laboratory

    2010-12-10

    An overview of key issues relevant to safeguards by design (SBD) for GEN III/IV nuclear reactors is provided. Lessons learned from construction of typical GEN III+ water reactors with respect to SBD are highlighted. Details of SBD for safeguards guidance development for GEN III/III+ light water reactors are developed and reported. This paper also identifies technical challenges to extend SBD including proliferation resistance methodologies to other GEN III/III+ reactors (except HWRs) and GEN IV reactors because of their immaturity in designs.

  17. Light interception, utilisation and conversion efficiencies and yield performance of sweet potato, Ipomoea batatas, grown from IBA-treated basal and untreated terminal vine cuttings

    International Nuclear Information System (INIS)

    Nzima, M.D.S.

    1985-01-01

    Sweet potatoes grown from IBA-treated basal vines produced a significantly higher total yield of 28.99 t ha -1 and marketable tubers 23.54 t ha -1 , than those grown from untreated terminal vine cuttings which produced 22.43 and 17.46 t ha -1 of total and marketable tubers respectively. Field measurements indicated that IBA-treated basal vine plants were significantly less efficient in light interception, yet this treatment produced a higher proportion (31.20%) of large tubers, compared with untreated terminal vine plants (14.64%). Untreated terminal vine plants intercepted 95% of the incident solar radiation three weeks earlier than IBA-treated basal vine plants. However, the treatment increased the efficiency of converting light energy to chemical energy (Ec%) and of utilising this chemical energy to produce plant dry matter (Eu%) through an increased 'sink' demand. The practical implications of the results and future research are outlined

  18. A calibrated UV-LED based light source for water purification and characterisation of photocatalysis.

    Science.gov (United States)

    Sergejevs, A; Clarke, C T; Allsopp, D W E; Marugan, J; Jaroenworaluck, A; Singhapong, W; Manpetch, P; Timmers, R; Casado, C; Bowen, C R

    2017-11-08

    Photocatalysis has a potential to become a cost effective industrial process for water cleaning. One of the most studied photocatalysts is titanium dioxide which, as a wide band gap semiconductor, requires ultraviolet (UV) light for its photoactivation. This is at the wavelengths where the efficiency of present-day light emitting diodes (LEDs) decreases rapidly, which presents a challenge in the use of UV-LEDs for commercially viable photocatalysis. There is also a need for accurate photocatalysis measurement of remediation rates of water-borne contaminants for determining optimum exposure doses in industrial applications. In response to these challenges, this paper describes a UV-LED based photocatalytic test reactor that provides a calibrated adjustable light source and pre-defined test conditions to remove as many sources of uncertainty in photocatalytic analysis as possible and thereby improve data reliability. The test reactor provides a selectable intensity of up to 1.9 kW m -2 at the photocatalyst surface. The comparability of the results is achieved through the use of pre-calibration and control electronics that minimize the largest sources of uncertainty; most notably variations in the intensity and directionality of the UV light emission of LEDs and in LED device heating.

  19. Wastes and waste management in the uranium fuel cycle for light water reactors

    International Nuclear Information System (INIS)

    Costello, J.M.

    1975-08-01

    The manufacturing processes in the uranium fuel cycle for light water reactors have been described with particular reference to the chemical and radiological wastes produced and the waste management procedures employed. The problems and possible solutions of ultimate disposal of high activity fission products and transuranium elements from reprocessing of irradiated fuel have been reviewed. Quantities of wastes arising in each stage of the fuel cycle have been summarised. Wastes arising from reactor operation have been described briefly. (author)

  20. Measurement of the group velocity of light in sea water at the ANTARES site

    Science.gov (United States)

    Adrián-Martínez, S.; Al Samarai, I.; Albert, A.; André, M.; Anghinolfi, M.; Anton, G.; Anvar, S.; Ardid, M.; Assis Jesus, A. C.; Astraatmadja, T.; Aubert, J.-J.; Baret, B.; Basa, S.; Bertin, V.; Biagi, S.; Bigi, A.; Bigongiari, C.; Bogazzi, C.; Bou-Cabo, M.; Bouhou, B.; Bouwhuis, M. C.; Brunner, J.; Busto, J.; Camarena, F.; Capone, A.; Cârloganu, C.; Carminati, G.; Carr, J.; Cecchini, S.; Charif, Z.; Charvis, Ph.; Chiarusi, T.; Circella, M.; Costantini, H.; Coyle, P.; Curtil, C.; De Bonis, G.; Decowski, M. P.; Dekeyser, I.; Deschamps, A.; Distefano, C.; Donzaud, C.; Dornic, D.; Dorosti, Q.; Drouhin, D.; Eberl, T.; Emanuele, U.; Enzenhöfer, A.; Ernenwein, J.-P.; Escoffier, S.; Fermani, P.; Ferri, M.; Flaminio, V.; Folger, F.; Fritsch, U.; Fuda, J.-L.; Galatà, S.; Gay, P.; Geyer, K.; Giacomelli, G.; Giordano, V.; Gómez-González, J. P.; Graf, K.; Guillard, G.; Halladjian, G.; Hallewell, G.; van Haren, H.; Hartman, J.; Heijboer, A. J.; Hello, Y.; Hernández-Rey, J. J.; Herold, B.; Hößl, J.; Hsu, C. C.; de Jong, M.; Kadler, M.; Kalekin, O.; Kappes, A.; Katz, U.; Kavatsyuk, O.; Kooijman, P.; Kopper, C.; Kouchner, A.; Kreykenbohm, I.; Kulikovskiy, V.; Lahmann, R.; Lamare, P.; Larosa, G.; Lattuada, D.; Lefèvre, D.; Lim, G.; Lo Presti, D.; Loehner, H.; Loucatos, S.; Mangano, S.; Marcelin, M.; Margiotta, A.; Martínez-Mora, J. A.; McMillan, J. E.; Meli, A.; Montaruli, T.; Moscoso, L.; Motz, H.; Neff, M.; Nezri, E.; Palioselitis, D.; Păvălaş, G. E.; Payet, K.; Payre, P.; Petrovic, J.; Piattelli, P.; Picot-Clemente, N.; Popa, V.; Pradier, T.; Presani, E.; Racca, C.; Reed, C.; Riccobene, G.; Richardt, C.; Richter, R.; Rivière, C.; Robert, A.; Roensch, K.; Rostovtsev, A.; Ruiz-Rivas, J.; Rujoiu, M.; Russo, G. V.; Salesa, F.; Samtleben, D. F. E.; Sapienza, P.; Schöck, F.; Schuller, J.-P.; Schüssler, F.; Seitz, T.; Shanidze, R.; Simeone, F.; Spies, A.; Spurio, M.; Steijger, J. J. M.; Stolarczyk, Th.; Sánchez-Losa, A.; Taiuti, M.; Tamburini, C.; Thompson, L. F.; Toscano, S.; Vallage, B.; Van Elewyck, V.; Vannoni, G.; Vecchi, M.; Vernin, P.; Wagner, S.; Wijnker, G.; Wilms, J.; de Wolf, E.; Yepes, H.; Zaborov, D.; Zornoza, J. D.; Zúñiga, J.

    2012-04-01

    The group velocity of light has been measured at eight different wavelengths between 385 nm and 532 nm in the Mediterranean Sea at a depth of about 2.2 km with the ANTARES optical beacon systems. A parametrisation of the dependence of the refractive index on wavelength based on the salinity, pressure and temperature of the sea water at the ANTARES site is in good agreement with these measurements.

  1. Advanced Light Water Reactor Program: Program management and staff review methodology

    International Nuclear Information System (INIS)

    Moran, D.H.

    1986-12-01

    This report summarizes the NRC/EPRI coordinated effort to develop design requirements for a standardized advanced light water reactor (ALWR) and the procedures for screening and applying new generic safety issues to this program. The end-product will be an NRC-approved ALWR Requirements Document for use by the nuclear industry in generating designs of LWRs to be constructed for operation in the 1990s and beyond

  2. Study on the Use of Hydride Fuel in High-Performance Light Water Reactor Concept

    OpenAIRE

    Haileyesus Tsige-Tamirat; Luca Ammirabile

    2015-01-01

    Hydride fuels have features which could make their use attractive in future advanced power reactors. The potential benefit of use of hydride fuel in HPLWR without introducing significant modification in the current core design concept of the high-performance light water reactor (HPLWR) has been evaluated. Neutronics and thermal hydraulic analyses were performed for a single assembly model of HPLWR with oxide and hydride fuels. The hydride assembly shows higher moderation with softer neutron s...

  3. Analysis of enriched UO2 light water moderated lattices using CAROL code

    International Nuclear Information System (INIS)

    Bhatia, H.K.; Thaker, K.

    1978-01-01

    An analysis of uniform lattice experiments for enriched UO 2 rods in light water moderator using CAROL code is presented. The experiments selected have four different enrichments and moderator to fuel volume ratio varying between 1 to 4. The deviation of ksub(eff) has been observed to lie between +- 0.01 over the important range of moderator to fuel volume ratio. In addition to reactivity prediction, the calculated and measured relative reaction rates have also been compared. (author)

  4. Literature search on Light Water Reactor (LWR) fuel and absorber rod fabrication, 1960--1976

    Energy Technology Data Exchange (ETDEWEB)

    Sample, C R [comp.

    1977-02-01

    A literature search was conducted to provide information supporting the design of a conceptual Light Water Reactor (LWR) Fuel Fabrication plant. Emphasis was placed on fuel processing and pin bundle fabrication, effects of fuel impurities and microstructure on performance and densification, quality assurance, absorber and poison rod fabrication, and fuel pin welding. All data have been taken from publicly available documents, journals, and books. This work was sponsored by the Finishing Processes-Mixed Oxide (MOX) Fuel Fabrication Studies program at HEDL.

  5. A design study of high electric power for fast reactor cooled by supercritical light water

    Energy Technology Data Exchange (ETDEWEB)

    Koshizuka, Seiichi [Tokyo Univ., Tokai, Ibaraki (Japan). Nuclear Engineering Research Lab

    2000-03-01

    In order to evaluate the possibility to achieve high electric power by a fast reactor with supercritical light water, the design study was carried out on a large fast reactor core with high coolant outlet temperature (SCFR-H). Since the reactor coolant circuit uses once-through direct cycle where all feedwater flows through the core to the turbine at supercritical pressure, it is possible to design much simpler and more compact reactor systems and to achieve higher thermal efficiency than those of current light water reactors. The once-through direct cycle system is employed in current fossil-fired power plants. In the present study, three types of core were designed. The first is SCFR-H with blankets cooled by ascending flow, the second is SCFR-H with blankets cooled by descending flow and the third is SCFR-H with high thermal power. Every core was designed to achieve the thermal efficiency over 43%, positive coolant density reactivity coefficient and electric power over 1600 MW. Core characteristics of SCFR-Hs were compared with those of SCLWR-H (electric power: 1212 MW), which is a thermal neutron spectrum reactor cooled and moderated by supercritical light water, with the same diameter of the reactor pressure vessel. It was shown that SCFR-H could increase the electric power about 1.7 times maximally. From the standpoint of the increase of a reactor thermal power, a fast reactor has advantages as compared with a thermal neutron reactor, because it can increase the power density by adopting tight fuel lattices and eliminating the moderator region. Thus, it was concluded that a reactor cooled by supercritical light water could further improve the cost competitiveness by using a fast neutron spectrum and achieving a higher thermal power. (author)

  6. Evaluation of actinide partitioning and transmutation in light-water reactors

    International Nuclear Information System (INIS)

    Collins, Emory D.; Renier, John-Paul

    2004-01-01

    Advanced Fuel Cycle Initiative (AFCI) studies were made to evaluate the feasibility of multicycle transmutation of plutonium and the minor actinides (MAs) in light-water reactors (LWRs). Results showed that significant repository benefits, cost reductions, proliferation resistance, and effective use of facilities can be obtained. Key advantages are shown to be made possible by processing 30-year-decayed spent fuel rather than the more traditional 5-year-decayed fuel. (authors)

  7. Literature search on Light Water Reactor (LWR) fuel and absorber rod fabrication, 1960--1976

    International Nuclear Information System (INIS)

    Sample, C.R.

    1977-02-01

    A literature search was conducted to provide information supporting the design of a conceptual Light Water Reactor (LWR) Fuel Fabrication plant. Emphasis was placed on fuel processing and pin bundle fabrication, effects of fuel impurities and microstructure on performance and densification, quality assurance, absorber and poison rod fabrication, and fuel pin welding. All data have been taken from publicly available documents, journals, and books. This work was sponsored by the Finishing Processes-Mixed Oxide (MOX) Fuel Fabrication Studies program at HEDL

  8. [Microcystin in plants that treat water for human consumption in a tropical environment: the Metropolitan Area of Costa Rica].

    Science.gov (United States)

    Lopez, Adrián Avendaño; Villa, Carolina Arguedas

    2006-09-01

    We measured microcystin levels in water of the Metropolitan Area of Costa Rica by competitive inhibition ELISA and we quantified total coliforms, fecal coliforms, Escherichia coli (by a Most Probable Number method) and aerobic count. We wanted to identify any cyanotoxin correlation with these parameters, as a public health risk. We sampled in the rainy season of 2003 (April-October) and in the dry season of 2004 (February-March) (30 samples/season). We sampled pre-treated, semi-treated and treated water. Microcystin levels 0.5 ppb in the dry season). Dry season levels exceeded World Health Organization limits (1.0 ppb). Cyanotoxins occurred in the Tres Rios plant. We did not find a correlation between these microbiologic parameters of water quality and microcystin levels in water.

  9. Photoreactivation of Pseudomonas cepacia after ultraviolet exposure: a potential source of contamination in ultraviolet-treated waters

    International Nuclear Information System (INIS)

    Carson, L.A.; Petersen, N.J.

    1975-01-01

    Cells of a naturally occurring strain of Pseudomonas cepacia grown in distilled water were exposed to ultraviolet radiation. Irradiated samples incubated on membrane filters or in fluid recovery media in the absence of light showed no evidence of dark repair mechanisms. When samples were exposed to fluorescent light ranging from 50 to 950 foot candles (538 to 10,222 lux) of illumination, apparent photo-induced repair of ultraviolet injury resulted in 1- to 4-log increases in viable cells recovered

  10. Design parameters of high rate algal ponds using filamentous algae matrix for treating rural stream water.

    Science.gov (United States)

    Kim, T E; Chung, W M; Lim, B S

    2002-01-01

    High rate algal ponds (HRAP) with a filamentous algae matrix (FAM) as the predominant species, were operated to evaluate the characteristics of FAM and the basic design parameters for treating polluted rural stream water. The porous and gelatinous FAM was formed like a sponge, which functions to prevent excessive loss of the algae in the effluent and can easily be retrieved from the ponds. The organic fraction of harvested FAM was about 88%, which is suitable for use as fertilizer. The HRAP system using FAM was found to be an effective nutrient removal process not requiring any artificial carbon sources for nitrification. At HRT 4 days, the T-N and T-P removal efficiencies were 85.9% and 65.8%, respectively. When the pH and water temperature were maintained above 9 and 15 degrees C, HRT required for achieving a 70% T-N removal efficiency could be reduced by about 3 days. The oxygen production rate by FAM was calculated as 1.45 mgO2/L/m2. The design surface area of HRAP needed per rural inhabitant was about 2.72 m2.

  11. Analysis of water leached from soil treated with leachate from plant biomass ash

    Directory of Open Access Journals (Sweden)

    Everton Skoronski

    2017-09-01

    Full Text Available This work analyzed water leached from soil treated with leachate from plant biomass ash. The ash was generated by industrial boilers used in the pulp and paper industry. Experiments were carried out in columns filled with soil, and the ash was then added to the soil to simulate field conditions. The ash was applied at 30 and 60 tons per hectare rate. The simulated rainwater was prepared for three scenarios: pH 3.0, 6.5 and 8.0. Each leaching experiment simulated an annual precipitation of 2,045 mm. The results showed that the parameter that demands more attention is aluminum concentration. In this context, in acidic conditions (pH 3.0 and with a significant amount of ash added (60 tons per hectare, the level of aluminum may reach the maximum level for drinking water. Despite the potential impact of aluminum, the use of ash from plant biomass in soil for agricultural purposes may serve as an alternative strategy for disposal of this waste.

  12. Prevalence of bacterial contamination with antibiotic-resistant and enterotoxigenic fecal coliforms in treated drinking water.

    Science.gov (United States)

    Pathak, S P; Gopal, K

    2008-01-01

    Pollution indicator bacteria such as coliforms, fecal coliforms, and fecal streptococci were enumerated using a multiple-tube fermentation method in 100 treated drinking-water samples from 20 locations in residential, commercial, and industrial areas of a tropical city during summer. Thirty-four percent of the samples were bacteriologically nonpotable. Maximum coliform-contaminated (27%) samples were derived from industrial areas, while samples contaminated with fecal coliform (23%) and fecal streptococci (20%) originated from commercial areas. Coliforms identified as Escherichia coli, Klebsiella sp., Enterobacter sp., and Citrobacter sp. were present in 29%, 26%, 24%, and 15% of samples, respectively. Fecal coliforms were examined for antibiotic susceptibility with disc diffusion method. All test isolates exhibited multiple antibiotic resistance (MAR) for kanamycin, nalidixic acid, tetracycline, and trimethoprim. Escherichia coli isolates were examined for enterotoxigenicity using the suckling mice bioassay and 60% of the isolates displayed enterotoxigenicity. Data indicate that drinking water contaminated with antibiotic-resistant enterotoxigenic fecal bacteria may be responsible for presence of waterborne diarrheal diseases attributed to therapeutic agents used by urban populations in the tropics.

  13. Plasma-treated water eliminates Streptococcus mutans in infected dentin model.

    Science.gov (United States)

    Tasaki, Tatsuya; Ohshima, Tomoko; Usui, Emi; Ikawa, Satoshi; Kitano, Katsuhisa; Maeda, Nobuko; Momoi, Yasuko

    2017-07-26

    Non-mechanical procedures for removing caries-infected dentin are warranted in dentistry. We previously demonstrated the marked sterilization effect for direct irradiation of low-temperature plasma using dentin model infected with Streptococcus mutans. However it requires 180 s of intraoral plasma irradiation to eliminate bacteria. We alternatively investigated whether plasma-treated water (PTW), i.e., pure water exposed to plasma in an atmosphere, has a same bactericidal activity with the plasma irradiation. In the infected dentin model, the viable S. mutans counts recovered by bur at depth of 0.8-2.4 mm from the cavity floor were 10 4 -10 6 CFU/round bur. After PTW application for only 10 s, the count was significantly decreased to below the detection limit (2.5 CFU/round bur) or 3.0±5.0 CFU/round bur. Since the bactericidal activity of PTW is rapidly deactivated at body temperature (37°C), PTW is likely to be biocompatible and holds significant potential for non-mechanical procedures for removing caries-infected dentin.

  14. Research and development program for plutonium recycling in light water power plants: indirect nuclear action

    International Nuclear Information System (INIS)

    1977-01-01

    The report describes the state of advancement - 31/12/1976 - of the Community research and development programme on plutonium recycling in light-water power stations. The first part of the programme includes the forecast of the plutonium industry around 1990 and the assessment of the environmental impact due to the plutonium recycling in light-water power stations at this period. The forward study is available now, whereas the assessment studies concerning the environmental aspects have been the subject of a tender procedure among various European organizations. The improvement of scientific and technical knowledge which constitutes the second part of the programme, consists of three actions. The first one, practically achieved, collects the studies relating to the cross sections of higher plutonium isotopes and actinides and to the comparison of computer codes. The second one, relating to the safety and control of light-water reactors comprises seventeen projects which are under negociation with the contracting parties. The third one is composed of thirteen projects including post-irradiation examinations and isotopic analysis on plutonium fuels irradiated in L.W.R.'s; the available results are briefly described

  15. End-of-life destructive examination of light water breeder reactor fuel rods (LWBR Development Program)

    International Nuclear Information System (INIS)

    Richardson, K.D.

    1987-10-01

    Destructive examination of 12 representative Light Water Breeder Reactor fuel rods was performed following successful operation in the Shippingport Atomic Power Station for 29,047 effective full power hours, about five years. Light Water Breeder Reactor fuel rods were unique in that the thorium oxide and uranium-233 oxide fuel was contained within Zircaloy-4 cladding. Destructive examinations included analysis of released fission gas; chemical analysis of the fuel to determine depletion, iodine, and cesium levels; chemical analysis of the cladding to determine hydrogen, iodine, and cesium levels; metallographic examination of the cladding, fuel, and other rod components to determine microstructural features and cladding corrosion features; and tensile testing of the irradiated cladding to determine mechanical strength. The examinations confirmed that Light Water Breeder Reactor fuel rod performance was excellent. No evidence of fuel rod failure was observed, and the fuel operating temperature was low (below 2580 0 F at which an increased percentage of fission gas is released). 21 refs., 80 figs., 20 tabs

  16. Overview of the US Department of Energy Light Water Reactor Sustainability Program

    International Nuclear Information System (INIS)

    McCarthy, K.A.; Williams, D.L.; Reister, R.

    2012-01-01

    The US Department of Energy Light Water Reactor Sustainability (LWRS) Program is focused on enabling the long-term operation of US commercial power plants. Decisions on life extension will be made by commercial power plant owners - the information provided by the research and development activities in the LWRS Program will reduce the uncertainty (and therefore the risk) associated with making those decisions. The LWRS Program encompasses two facets of long-term operation: (1) manage the aging of plant systems, structures, and components so that nuclear power plant lifetimes can be extended and the plants can continue to operate safely, efficiently, and economically; and (2) provide science-based solutions to the nuclear industry that support implementation of performance improvement technologies. An important aspect of the Light Water Reactor Sustainability Program is partnering with industry and the Nuclear Regulatory Commission to support and conduct the long-term research needed to inform major component refurbishment and replacement strategies, performance enhancements, plant license extensions, and age-related regulatory oversight decisions. The Department of Energy research, development, and demonstration role focuses on aging phenomena and issues that require long-term research and/or unique Department of Energy laboratory expertise and facilities and are applicable to all operating reactors. This paper provides an overview of the Department of Energy Light Water Reactor Sustainability Program, including vision, goals, and major deliverables. (author)

  17. USEPA/USGS Study of CECs in Source Water and Treated Drinking Water: Assessment of Estrogenic Activity Using an In Vitro Bioassay, T47D-KBluc.

    Science.gov (United States)

    Scientists from the U.S. Environmental Protection Agency (EPA) and U.S. Geological Survey (USGS) are collaborating on a research study to determine the presence of contaminants of emerging concern in treated and untreated drinking water collected from up to 50 drinking water trea...

  18. Installation of the Light-Water Breeder Reactor at the Shippingport Atomic Power Station (LWBR Development Program)

    International Nuclear Information System (INIS)

    Massimino, R.J.; Williams, D.A.

    1983-05-01

    This report summarizes the refueling operations performed to install a Light Water Breeder Reactor (LWBR) core into the existing pressurized water reactor vessel at the Shippingport Atomic Power Station. Detailed descriptions of the major installation operations (e.g., primary system preconditioning, fuel installation, pressure boundary seal welding) are included as appendices to this report; these operations are of technical interest to any reactor servicing operation, whether the reactor is a breeder or a conventional light water non-breeder core

  19. Installation of the Light-Water Breeder Reactor at the Shippingport Atomic Power Station (LWBR Development Program)

    Energy Technology Data Exchange (ETDEWEB)

    Massimino, R.J.; Williams, D.A.

    1983-05-01

    This report summarizes the refueling operations performed to install a Light Water Breeder Reactor (LWBR) core into the existing pressurized water reactor vessel at the Shippingport Atomic Power Station. Detailed descriptions of the major installation operations (e.g., primary system preconditioning, fuel installation, pressure boundary seal welding) are included as appendices to this report; these operations are of technical interest to any reactor servicing operation, whether the reactor is a breeder or a conventional light water non-breeder core.

  20. Oak Ridge National Laboratory Support of Non-light Water Reactor Technologies: Capabilities Assessment for NRC Near-term Implementation Action Plans for Non-light Water Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Belles, Randy [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Jain, Prashant K. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Powers, Jeffrey J. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2017-04-01

    The Oak Ridge National Laboratory (ORNL) has a rich history of support for light water reactor (LWR) and non-LWR technologies. The ORNL history involves operation of 13 reactors at ORNL including the graphite reactor dating back to World War II, two aqueous homogeneous reactors, two molten salt reactors (MSRs), a fast-burst health physics reactor, and seven LWRs. Operation of the High Flux Isotope Reactor (HFIR) has been ongoing since 1965. Expertise exists amongst the ORNL staff to provide non-LWR training; support evaluation of non-LWR licensing and safety issues; perform modeling and simulation using advanced computational tools; run laboratory experiments using equipment such as the liquid salt component test facility; and perform in-depth fuel performance and thermal-hydraulic technology reviews using a vast suite of computer codes and tools. Summaries of this expertise are included in this paper.

  1. Influence of Type of Electric Bright Light on the Attraction of the African Giant Water Bug, Lethocerus indicus (Hemiptera: Belostomatidae

    Directory of Open Access Journals (Sweden)

    Luke Chinaru Nwosu

    2012-01-01

    Full Text Available This study investigated the influence of type of electric bright light (produced by fluorescent light tube and incandescent light bulb on the attraction of the African giant water bug, Lethocerus indicus (Hemiptera: Belostomatidae. Four fluorescent light tubes of 15 watts each, producing white-coloured light and four incandescent light bulbs of 60 watts each, producing yellow-coloured light, but both producing the same amount of light, were varied and used for the experiments. Collections of bugs at experimental house were done at night between the hours of 8.30 pm and 12 mid-night on daily basis for a period of four months per experiment in the years 2008 and 2009. Lethocerus indicus whose presence in any environment has certain implications was the predominant belostomatid bug in the area. Use of incandescent light bulbs in 2009 significantly attracted more Lethocerus indicus 103 (74.6% than use of fluorescent light tubes 35 (25.41% in 2008 [4.92=0.0001]. However, bug’s attraction to light source was not found sex dependent [>0.05; (>0.18=0.4286 and >0.28=0.3897]. Therefore, this study recommends the use of fluorescent light by households, campgrounds, and other recreational centres that are potentially exposed to the nuisance of the giant water bugs. Otherwise, incandescent light bulbs should be used when it is desired to attract the presence of these aquatic bugs either for food or scientific studies.

  2. DESIGN COMPARISON OF EXPERIMENTAL STORM WATER DETENTION SYSTEMS TREATING CONCENTRATED ROAD RUNOFF

    Directory of Open Access Journals (Sweden)

    H. Nanbakhsh

    2005-07-01

    Full Text Available Urban drainage systems are vital infrastructure assets, which protect our cities from flooding and transmission of waterborne diseases. The objective of this research was to assess the treatment efficiencies of experimental stormwater detention (extended storage systems receiving concentrated runoff that had been primary treated by filtration with different aggregates. Five detention systems with different packing order arrangements of aggregates and plant roots were used in the system to test the effects of gravel, sand, ecosoil, block paving and turf on the water treatment performance. Inflow water, polluted by road runoff, was collected by manual abstraction with a 2 litter beaker from randomly selected gully pots the near by main roads. Several parameters such as BOD5, NO3, PO4, NH4, SS, TS, DO, pH, EC, NTU and temperature were examined based on standard method book. Results showed that concentrations of biochemical oxygen demand (BOD5 in contrast to suspended solids (SS were frequently reduced to below international secondary wastewater treatment standards. The BOD and SS concentrations within the outflow from the planted system compared to the unplanted gravel and sand systems were similar. However, BOD in the outflow of system 5 was lower than other systems. The denitrification process was not completed. This resulted in higher outflow than inflow nitrate-nitrogen concentrations. An analysis of variance indicated that some systems were similar in terms of most of their treatment performance variables including BOD and SS. It follows that there is no need to use additional aggregates with high adsorption capacities in the primary treatment stage from the water quality point of view.

  3. Minimizing residual aluminum concentration in treated water by tailoring properties of polyaluminum coagulants.

    Science.gov (United States)

    Kimura, Masaoki; Matsui, Yoshihiko; Kondo, Kenta; Ishikawa, Tairyo B; Matsushita, Taku; Shirasaki, Nobutaka

    2013-04-15

    Aluminum coagulants are widely used in water treatment plants to remove turbidity and dissolved substances. However, because high aluminum concentrations in treated water are associated with increased turbidity and because aluminum exerts undeniable human health effects, its concentration should be controlled in water treatment plants, especially in plants that use aluminum coagulants. In this study, the effect of polyaluminum chloride (PACl) coagulant characteristics on dissolved residual aluminum concentrations after coagulation and filtration was investigated. The dissolved residual aluminum concentrations at a given coagulation pH differed among the PACls tested. Very-high-basicity PACl yielded low dissolved residual aluminum concentrations and higher natural organic matter (NOM) removal. The low residual aluminum concentrations were related to the low content of monomeric aluminum (Ala) in the PACl. Polymeric (Alb)/colloidal (Alc) ratio in PACl did not greatly influence residual aluminum concentration. The presence of sulfate in PACl contributed to lower residual aluminum concentration only when coagulation was performed at around pH 6.5 or lower. At a wide pH range (6.5-8.5), residual aluminum concentrations residual aluminum concentrations did not increase with increasing the dosage of high-basicity PACl, but did increase with increasing the dosage of normal-basicity PACl. We inferred that increasing the basicity of PACl afforded lower dissolved residual aluminum concentrations partly because the high-basicity PACls could have a small percentage of Ala, which tends to form soluble aluminum-NOM complexes with molecular weights of 100 kDa-0.45 μm. Copyright © 2013 Elsevier Ltd. All rights reserved.

  4. Competition for light and water in a coupled soil-plant system

    Science.gov (United States)

    Manoli, Gabriele; Huang, Cheng-Wei; Bonetti, Sara; Domec, Jean-Christophe; Marani, Marco; Katul, Gabriel

    2017-10-01

    It is generally accepted that resource availability shapes the structure and function of many ecosystems. Within the soil-plant-atmosphere (SPA) system, resource availability fluctuates in space and time whereas access to resources by individuals is further impacted by plant-to-plant competition. Likewise, transport and transformation of resources within an individual plant is governed by numerous interacting biotic and abiotic processes. The work here explores the co-limitations on water losses and carbon uptake within the SPA arising from fluctuating resource availability and competition. In particular, the goal is to unfold the interplay between plant access and competition for water and light, as well as the impact of transport/redistribution processes on leaf-level carbon assimilation and water fluxes within forest stands. A framework is proposed that couples a three-dimensional representation of soil-root exchanges with a one-dimensional description of stem water flow and storage, canopy photosynthesis, and transpiration. The model links soil moisture redistribution, root water uptake, xylem water flow and storage, leaf potential and stomatal conductance as driven by supply and demand for water and carbon. The model is then used to investigate plant drought resilience of overstory-understory trees simultaneously competing for water and light. Simulation results reveal that understory-overstory interactions increase ecosystem resilience to drought (i.e. stand-level carbon assimilation rates and water fluxes can be sustained at lower root-zone soil water potentials). This resilience enhancement originates from reduced transpiration (due to shading) and hydraulic redistribution in soil supporting photosynthesis over prolonged periods of drought. In particular, the presence of different rooting systems generates localized hydraulic redistribution fluxes that sustain understory transpiration through overstory-understory interactions. Such complex SPA dynamics

  5. Dynamic Response of Plant Chlorophyll Fluorescence to Light, Water and Nutrient Availability

    Science.gov (United States)

    Cendrero Mateo, M. D. P.; Moran, S. M.; Porcar-Castell, A.; Carmo-Silva, A. E.; Papuga, S. A.; Matveeva, M.; Wieneke, S.; Rascher, U.

    2014-12-01

    Photosynthesis is the most important exchange process of CO2 between the atmosphere and the land-surface. Spatial and temporal patterns of photosynthesis depend on dynamic plant-specific adaptation strategies to highly variable environmental conditions e.g. light, water, and nutrient availability. Chlorophyll fluorescence (ChF) has been proposed as a direct indicator of photosynthesis, and several studies have demonstrated its relationship with vegetation functioning at leaf and canopy level. In this study, two overarching questions about ChF were addressed: Q1) How water, nutrient and ambient light conditions determine the relationships between photosynthesis and ChF? Which is the optimum irradiance level for detecting water and nutrient deficit conditions with ChF?; Q2) What is the seasonal relationship between photosynthesis and ChF when nitrogen is the limiting factor? The results of this study indicated that when the differences between treatments (water or nitrogen) drive the relationship between photosynthesis and ChF, ChF has a direct relationship with photosynthesis. This study demonstrates that the light level at which plants were grown was optimum for detecting water and nutrient deficit with ChF. Further, the seasonal relation between photosynthesis and ChF with nitrogen stress was not a simple linear function due to the complex physiological relation between photosynthesis and ChF. Our study showed that at times in the season when nitrogen was sufficient and photosynthesis was highest, ChF decreased because these two processes compete for available energy. The results from this study demonstrated that ChF is a reliable indicator of plant stress and has great potential as a tool for better understand where, when, and how CO2 is exchanged between the land and atmosphere.

  6. Comparison of in vitro estrogenic activity and estrogen concentrations in source and treated waters from 25 U.S. drinking water treatment plants.

    Science.gov (United States)

    Conley, Justin M; Evans, Nicola; Mash, Heath; Rosenblum, Laura; Schenck, Kathleen; Glassmeyer, Susan; Furlong, Ed T; Kolpin, Dana W; Wilson, Vickie S

    2017-02-01

    In vitro bioassays have been successfully used to screen for estrogenic activity in wastewater and surface water, however, few have been applied to treated drinking water. Here, extracts of source and treated water samples were assayed for estrogenic activity using T47D-KBluc cells and analyzed by liquid chromatography-Fourier transform mass spectrometry (LC-FTMS) for natural and synthetic estrogens (including estrone, 17β-estradiol, estriol, and ethinyl estradiol). None of the estrogens were detected above the LC-FTMS quantification limits in treated samples and only 5 source waters had quantifiable concentrations of estrone, whereas 3 treated samples and 16 source samples displayed in vitro estrogenicity. Estrone accounted for the majority of estrogenic activity in respective samples, however the remaining samples that displayed estrogenic activity had no quantitative detections of known estrogenic compounds by chemical analyses. Source water estrogenicity (max, 0.47ng 17β-estradiol equivalents (E2Eq) L -1 ) was below levels that have been linked to adverse effects in fish and other aquatic organisms. Treated water estrogenicity (max, 0.078ngE2EqL -1 ) was considerably below levels that are expected to be biologically relevant to human consumers. Overall, the advantage of using in vitro techniques in addition to analytical chemical determinations was displayed by the sensitivity of the T47D-KBluc bioassay, coupled with the ability to measure cumulative effects of mixtures, specifically when unknown chemicals may be present. Published by Elsevier B.V.

  7. Volumetric dimensional changes of dental light-cured dimethacrylate resins after sorption of water or ethanol.

    Science.gov (United States)

    Sideridou, Irini D; Karabela, Maria M; Vouvoudi, Evagelia Ch

    2008-08-01

    This study evaluated the influence of water and ethanol sorption on the volumetric dimensional changes of resins prepared by light curing of Bis-GMA, Bis-EMA, UDMA, TEGDMA or D(3)MA. The resin specimens (15mm diameterx1mm height) were immersed in water or ethanol 37+/-1 degrees C for 30 days. Volumetric changes of specimens were obtained via accurate mass measurements using Archimedes principle. The specimens were reconditioned by dry storage in an oven at 37+/-1 degrees C until constant mass was obtained and then immersed in water or ethanol for 30 days. The volumetric changes of specimens were determined and compared to those obtained from the first sorption. Resins showed similar volume increase during the first and second sorptions of water or ethanol. The volume increase due to water absorption is in the following order: poly-TEGDMA>poly-Bis-GMA>poly-UDMA>poly-Bis-EMA>poly-D(3)MA. On the contrary, the order in ethanol is poly-Bis-GMA>poly-UDMA>poly-TEGDMA>poly-Bis-EMA approximately poly-D(3)MA. The volume increase was found to depend linearly on the amount of water or ethanol absorbed. In the choice of monomers for preparation of composite resin matrix the volume increase in the resin after immersion in water or ethanol must be taken into account. Resins of Bis-EMA and D(3)MA showed the lowest values.

  8. Gas-liquid-liquid equilibria in mixtures of water, light gases, and hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Chao, K.C.

    1990-01-01

    Phase equilibrium in mixtures of water + light gases and water + heavy hydrocarbons has been investigated with the development of new local composition theory, new equations of state, and new experimental data. The preferential segregation and orientation of molecules due to different energies of molecular interaction has been simulated with square well molecules. Extensive simulation has been made for pure square well fluids and mixtures to find the local composition at wide ranges of states. A theory of local composition has been developed and an equation of state has been obtained for square well fluids. The new local composition theory has been embedded in several equations of state. The pressure of water is decoupled into a polar pressure and non-polar pressure according to the molecular model of water of Jorgensen et al. The polar pressure of water is combined with the BACK equation for the general description of polar fluids and their mixtures. Being derived from the steam table, the Augmented BACK equation is particularly suited for mixtures of water + non-polar substances such as the hydrocarbons. The hydrophobic character of the hydrocarbons had made their mixtures with water a special challenge. A new group contribution equation of state is developed to describe phase equilibrium and volumetric behavior of fluids while requiring only to know the molecular structure of the components. 15 refs., 1 fig.

  9. Analysis on Radioactive Waste Transmutation in Light Water cooled Hyb-WT

    International Nuclear Information System (INIS)

    Hong, Seonghee; Kim, Myung Hyun

    2014-01-01

    A feasibility of realization is much higher in FFHR compared with pure fusion. A combination of plasma fusion source for neutrons with a subcritical reactor at the blanket side has much higher capability in transmutation of waste as well as reactor safety compared with fission reactor options. Fusion-Fission Hybrid Reactor (FFHR) uses various coolants depending on the purpose. It is important that coolant being used should be suitable to reactor purpose, because reactor performance and the design constraints may change depending on the coolant. There are basically two major groups of coolants for FFHR. One group of coolant does not contain Li. They are Na, Pb-Bi, H 2 O and D 2 O. The other group contains Li for tritium breeding. They are Li, LiPb, LiSN, FLIBE and FLiNaBe. Currently, the issue in FFHR is its implication for radioactive waste transmutation (FFHR for WT). Because radioactive wastes of spent nuclear fuel (SNF) are transmuted using fusion neutron source. Therefore a suitable coolant should be used for effective waste transmutation. . In FFHR for WT, LiPb coolant is being used mainly because of tritium production in Li and high neutron economic through reaction in Pb. However different coolants use such as Na, Pb-Bi are used in fast reactors and accelerator driven systems (ADS) having same purpose. In this study, radioactive waste transmutation performance of various coolants mentioned above will be compared and analyzed. Through this study, the coolants are judged primarily for their support to waste transmutation disregarding their limitation to reactor design and tritium breeding capability. First, performance of the light water coolant regarding radioactive waste transmutation was analyzed among various coolants mentioned above. In this paper, performance of radioactive waste transmutation can be known depending on different volume fractions (54.53, 60.27, 97.94vol.%) of the light water. Light water dose required fusion power lower than LiPb due to

  10. Underwater light field determined by water constituents in highly turbid water: the case of Taihu lake

    Directory of Open Access Journals (Sweden)

    Chang-Chun Huang

    2013-02-01

    Full Text Available The relationships between optical properties and water constituents in highly turbid productivewater were studied on the basis of the multiple bio-optical measurements and samplings of water constituents made during five cruises from 2006 to 2008 in Taihu lake. Taihu lake is a high dynamic ratio [(square root of area/depth] inland shallow lake. The spatial and temporal variation of water constituents and optical properties is significant. The inorganic suspended matter (ISMhas become the primary constituent in Taihu lake: its average percentage can reach 65.21%. The concentration of ISM is highly correlated to the optical properties in Taihu lake due to the sediment resuspension. Consequently, the ISM can be taken into account as an important optically-active constituent in Taihu lake. Resuspended sediments also lead to a poor correlation between scattering optical property and chlorophyll-a concentration (CChl-a. However, empirical relationship between the CChl-a and phytoplankton absorption coefficient at 675 nm is still valid when the package effect is removed. The parameters of linear equation in the present study have slight temporal variation, especially for the relationship between inherent optical properties (IOPs and concentration of total suspended matter (TSM. The relationship between apparent optical property (AOP (diffuse attenuation coefficient of particle, Kdbio and ISM has been examined as well. The Kdbio is strongly affected by ISM, and correlates to it with linear function. Thedifference between specific diffuse attenuation coefficients of organic [K*dOSM(λ] and inorganic [K*dISM(λ] particles is significant. K*dOSM(λ includes the absorption property of chlorophyll-a (chl-a at 675 nm, which is much higher than that of K*dISM(λ. This indicates that the attenuation ability of OSM is stronger than that of ISM although the Kdbio induced by large concentration of ISM is bigger than the Kdbio induced by small concentration of OSM

  11. Mechanism for migration of light nonaqueous phase liquids beneath the water table

    International Nuclear Information System (INIS)

    Krueger, J.P.; Portman, M.E.

    1991-01-01

    This paper reports on an interesting transport mechanism may account for the presence of light nonaqueous phase liquid (LNAPL) found beneath the water table in fine-grained aquifers. During the course of two separate site investigations related to suspected releases from underground petroleum storage tanks, LNAPL was found 7 to 10 feet below the regional water table. In both cases, the petroleum was present within a sand seam which was encompassed within a deposit of finer-grained sediments. The presence of LNAPL below the water table is uncommon; typically, LNAPL is found floating on the water table or on the capillary fringe. The occurrence of LNAPL below the water table could have resulted from fluctuating regional water levels which allowed the petroleum to enter the sand when the water table was a lower stage or, alternately, could have occurred as a result of the petroleum depressing the water table beneath the level of the sand. In fine-grained soils where the lateral migration rate is low, the infiltrating LNAPL may depress the water table to significant depth. The LNAPL may float on the phreatic surface with the bulk of its volume beneath the phreatic surface. Once present in the sand and surrounded by water-saturated fine-grained sediments, capillary forces prevent the free movement of the petroleum back across the boundary from the coarse-grained sediments to the fine-grained sediments. Tapping these deposits with a coarser grained filter packed monitoring well releases the LNAPL, which may accumulate to considerable thickness in the monitoring well

  12. Stability analysis of supercritical-pressure light water-cooled reactor in constant pressure operation

    International Nuclear Information System (INIS)

    Suhwan, JI; Shirahama, H.; Koshizuka, S.; Oka, Y.

    2001-01-01

    The purpose of this study is to evaluate the thermal-hydraulic and the thermal-nuclear coupled stabilities of a supercritical pressure light water-cooled reactor. A stability analysis code at supercritical pressure is developed. Using this code, stabilities of full and partial-power reactor operating at supercritical pressure are investigated by the frequency-domain analysis. Two types of SCRs are analyzed; a supercritical light water reactor (SCLWR) and a supercritical water-cooled fast reactor (SCFR). The same stability criteria as Boiling Water Reactor are applied. The thermal-hydraulic stability of SCLWR and SCFR satisfies the criteria with a reasonable orifice loss coefficient. The decay ratio of the thermal-nuclear coupled stability in SCFR is almost zero because of a small coolant density coefficient of the fast reactor. The evaluated decay ratio of the thermal-nuclear coupled stability is 3,41 ∼ 10 -V at 100% power in SCFR and 0,028 at 100% power in SCLWR. The sensitivity is investigated. It is found that the thermal-hydraulic stability is sensitive to the mass flow rate strongly and the thermal-nuclear coupled stability to the coolant density coefficient. The bottom power peak distribution makes the thermal-nuclear stability worse and the thermal-nuclear stability better. (author)

  13. Secondary flows in the cooling channels of the high-performance light-water reactor

    Energy Technology Data Exchange (ETDEWEB)

    Laurien, E.; Wintterle, Th. [Stuttgart Univ., Institute for Nuclear Technolgy and Energy Systems (IKE) (Germany)

    2007-07-01

    The new design of a High-Performance Light-Water Reactor (HPLWR) involves a three-pass core with an evaporator region, where the compressed water is heated above the pseudo-critical temperature, and two superheater regions. Due to the strong dependency of the supercritical water density on the temperature significant mass transfer between neighboring cooling channels is expected if the temperature is unevenly distributed across the fuel element. An inter-channel flow is then superimposed to the secondary flow vortices induced by the non-isotropy of turbulence. In order to gain insight into the resulting flow patterns as well as into temperature and density distributions within the various subchannels of the fuel element CFD (Computational Fluid Dynamics) calculations for the 1/8 fuel element are performed. For simplicity adiabatic boundary conditions at the moderator box and the fuel element box are assumed. Our investigation confirms earlier results obtained by subchannel analysis that the axial mass flux is significantly reduced in the corner subchannel of this fuel element resulting in a net mass flux towards the neighboring subchannels. Our results provide a first estimation of the magnitude of the secondary flows in the pseudo-critical region of a supercritical light-water reactor. Furthermore, it is demonstrated that CFD is an efficient tool for investigations of flow patterns within nuclear reactor fuel elements. (authors)

  14. Guidebook on quality control of mixed oxides and gadolinium bearing fuels for light water reactors

    International Nuclear Information System (INIS)

    1991-02-01

    Under the coverage of an efficient quality assurance system, quality control in nuclear fuel fabrication is an essential element to assure the reliable performance of all its components in service. Incentives to increase fuel performance, by extending reactor cycles or achieving higher burnups and, in some countries to use recycled plutonium in light water reactors (LWRs) necessitated the development of new types of fuels. In the first case, due to higher uranium enrichments, a burnable neutron absorber was integrated to the fuel pellets. Gadolinia was found to form a solid solution with Uranium dioxide and, to present a burnup rate which matches fissile uranium depletion. (U,Gd)O 2 fuels which have been successfully used since the seventies, in boiling water reactors have more recently found an increased utilization, in pressurized water reactors. This amply justifies the publication of this TECDOC to encourage authorities, designers and manufacturers of these types of fuel to establish a more uniform, adapted and effective system of control, thus promoting improved materials reliability and good performance in advanced fuel for light water reactors. The Guidebook is subdivided into four chapters written by different authors. A separate abstract was prepared for each of these chapters. Refs, figs and tabs

  15. Neutron absorption profile in a reactor moderated by different mixtures of light and heavy waters

    International Nuclear Information System (INIS)

    Nagy, Mohamed E.; Aly, Mohamed N.; Gaber, Fatma A.; Dorrah, Mahmoud E.

    2014-01-01

    Highlights: • We studied neutron absorption spectra in a mixed water moderated reactor. • Changing D 2 O% in moderator induced neutron energy spectral shift. • Most of the neutrons absorbed in control rods were epithermal. • Control rods worth changes were not proportional to changes of D 2 O% in moderator. • Control rod arrangement influenced the neutronic behavior of the reactor. - Abstract: A Monte-Carlo parametric study was carried out to investigate the neutron absorption profile in a model of LR-0 reactor when it is moderated by different mixtures of heavy/light waters at molecular ratios ranging from 0% up to 100% D 2 O at increments of 10% in D 2 O. The tallies included; neutron absorption profiles in control rods and moderator, and neutron capture profile in 238 U. The work focused on neutron absorption in control rods entailing; total mass of control rods needed to attain criticality, neutron absorption density and total neutron absorption in control rods at each of the studied mixed water moderators. The aim was to explore whether thermal neutron poisons are the most suitable poisons to be used in control rods of nuclear reactors moderated by mixed heavy/light water moderators

  16. Efficient Light-Driven Water Oxidation Catalysis by Dinuclear Ruthenium Complexes.

    Science.gov (United States)

    Berardi, Serena; Francàs, Laia; Neudeck, Sven; Maji, Somnath; Benet-Buchholz, Jordi; Meyer, Franc; Llobet, Antoni

    2015-11-01

    Mastering the light-induced four-electron oxidation of water to molecular oxygen is a key step towards the achievement of overall water splitting to produce alternative solar fuels. In this work, we report two rugged molecular pyrazolate-based diruthenium complexes that efficiently catalyze visible-light-driven water oxidation. These complexes were fully characterized both in the solid state (by X-ray diffraction analysis) and in solution (spectroscopically and electrochemically). Benchmark performances for homogeneous oxygen production have been obtained for both catalysts in the presence of a photosensitizer and a sacrificial electron acceptor at pH 7, and a turnover frequency of up to 11.1 s(-1) and a turnover number of 5300 were obtained after three successive catalytic runs. Under the same experimental conditions with the same setup, the pyrazolate-based diruthenium complexes outperform other well-known water oxidation catalysts owing to both electrochemical and mechanistic aspects. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Feasibility Study of Supercritical Light Water Cooled Fast Reactors for Actinide Burning and Electric Power Production

    Energy Technology Data Exchange (ETDEWEB)

    Mac Donald, Philip Elsworth; Buongiorno, Jacopo; Davis, Cliff Bybee; Weaver, Kevan Dean

    2002-01-01

    The use of supercritical temperature and pressure light water as the coolant in a direct-cycle nuclear reactor offers potential for considerable plant simplification and consequent capital and O&M cost reduction compared with current light water reactor (LWR) designs. Also, given the thermodynamic conditions of the coolant at the core outlet (i.e. temperature and pressure beyond the water critical point), very high thermal efficiencies of the power conversion cycle are possible (i.e. up to 46%). Because no change of phase occurs in the core, the need for steam separators and dryers as well as for BWR-type recirculation pumps is eliminated, which, for a given reactor power, results in a substantially shorter reactor vessel than the current BWRs. Furthermore, in a direct cycle the steam generators are not needed. If a tight fuel rod lattice is adopted, it is possible to significantly reduce the neutron moderation and attain fast neutron energy spectrum conditions. In this project a supercritical water reactor concept with a simple, blanket-free, pancake-shaped core will be developed. This type of core can make use of either fertile or fertile-free fuel and retain the hard spectrum to effectively burn plutonium and minor actinides from LWR spent fuel while efficiently generating electricity.

  18. Light Modulation and Water Splitting Enhancement Using a Composite Porous GaN Structure.

    Science.gov (United States)

    Yang, Chao; Xi, Xin; Yu, Zhiguo; Cao, Haicheng; Li, Jing; Lin, Shan; Ma, Zhanhong; Zhao, Lixia

    2018-02-14

    On the basis of the laterally porous GaN, we designed and fabricated a composite porous GaN structure with both well-ordered lateral and vertical holes. Compared to the plane GaN, the composite porous GaN structure with the combination of the vertical holes can help to reduce UV reflectance and increase the saturation photocurrent during water splitting by a factor of ∼4.5. Furthermore, we investigated the underlying mechanism for the enhancement of the water splitting performance using a finite-difference time-domain method. The results show that the well-ordered vertical holes can not only help to open the embedded pore channels to the electrolyte at both sides and reduce the migration distance of the gas bubbles during the water splitting reactions but also help to modulate the light field. Using this composite porous GaN structure, most of the incident light can be modulated and trapped into the nanoholes, and thus the electric fields localized in the lateral pores can increase dramatically as a result of the strong optical coupling. Our findings pave a new way to develop GaN photoelectrodes for highly efficient solar water splitting.

  19. Mixing of cooling water in the mixing chambers of the HPLWR-High Performance Light Water Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Wank, Alexander, E-mail: alexander.wank@siemens.co [Karlsruhe Institute of Technology (KIT), Institute for Nuclear and Energy Technologies, P.O. Box 3640, 76021 Karlsruhe (Germany); Starflinger, Joerg; Schulenberg, Thomas [Karlsruhe Institute of Technology (KIT), Institute for Nuclear and Energy Technologies, P.O. Box 3640, 76021 Karlsruhe (Germany); Laurien, Eckart [University of Stuttgart, Institute for Nuclear Technology and Energy Systems (IKE) Pfaffenwaldring 31, D-70550 Stuttgart (Germany)

    2010-10-15

    The High Performance Light Water Reactor (HPLWR), a supercritical water cooled reactor concept with multiple heat-up steps, requires efficient mixing of the coolant between these steps to minimize hot spots in the core. Analyzing and improving the mixing in the mixing chamber above the core, situated between evaporator and superheater assemblies, and below the core, between the first and second superheater, is one of the challenges in the design process of the HPLWR. Different measures to enhance mixing have been studied with CFD analyses, in which a new design approach has been applied to the upper mixing chamber. It simplifies the complex structures and takes the effects of the disregarded structures into account by introducing source terms into the momentum equations.

  20. Application of water-assisted ultraviolet light processing on the inactivation of murine norovirus on blueberries.

    Science.gov (United States)

    Liu, Chuhan; Li, Xinhui; Chen, Haiqiang

    2015-12-02

    In this study, a novel set-up using water-assisted UV processing was developed and evaluated for its decontamination efficacy against murine norovirus (MNV-1) inoculated on fresh blueberries for both small and large-scale experimental setups. Blueberries were skin-inoculated with MNV-1 and treated for 1-5 min with UV directly (dry UV) or immersed in agitated water during UV treatment (water-assisted UV). The effect of the presence of 2% (v/v) blueberry juice or 5% crushed blueberries (w/w) in wash water was also evaluated. Results showed that water-assisted UV treatment generally showed higher efficacies than dry UV treatment. With 12,000 J/m(2) UV treatment in small-scale setup, MNV reductions of >4.32- and 2.48-log were achieved by water-assisted UV and dry UV treatments, respectively. Water-assisted UV showed similar inactivating efficacy as 10-ppm chlorine wash. No virus was detected in wash water after UV treatment or chlorine wash. MNV-1 was more easily killed on skin-inoculated blueberries compared with calyx-inoculated berries. When clear water was used as wash water in the large-scale setup, water-assisted UV treatment (UV dose of 12,000 J/m(2)) resulted in >3.20 log and 1.81 log MNV-1 reductions for skin- and calyx-inoculated berries, respectively. The presence of 2% blueberry juice in wash water decreased the decontamination efficacy of water-assisted UV and chlorine washing treatments. To improve the inactivation efficacy, the effect of combining water-assisted UV treatment with chlorine washing was also evaluated. The combined treatment had better or similar inactivation efficacy compared to water-assisted UV treatment and chlorine washing alone. Findings of this study suggest that water-assisted UV treatment could be used as an alternative to chlorine washing for blueberries and potentially for other fresh produce. Copyright © 2015 Elsevier B.V. All rights reserved.

  1. UV spectrophotometry for monitoring the performance of a yeast-based deoxygenation process to treat ships' ballast water.

    Science.gov (United States)

    Veilleux, Éloïse; de Lafontaine, Yves; Thomas, Olivier

    2016-04-01

    This study assessed the usefulness of UV spectrophotometry for the monitoring of a yeast-based deoxygenation process proposed for ships' ballast water treatment to prevent the transfer of aquatic invasive species. Ten-day laboratory experiments using three treatment concentrations and different water types were conducted and resulted in complete oxygen depletion of treated waters. The treatment performance and quality of treated waters were determined by measuring the UV-visible absorbance spectra of water samples taken over time. Samples were also used for laboratory analysis of water quality properties. The UV absorbance spectra values were strongly correlated (r = 0.96) to yeast cell density in treated waters. The second-order derivative (D (2)) of the spectra varied greatly over time, and the spectrum profiles could be divided into two groups corresponding to the oxygenated and anoxic phases of the treatment. The D (2) value at 215 nm was strongly correlated (r = 0.94) to ammonia levels, which increased over time. The D (2) value at 225 nm was strongly correlated (r > 0.97) to DO concentration. Our results showed that UV spectrophotometry may provide a rapid assessment of the behavior and performance of the yeast bioreactor over time by quantifying (1) the density of yeast cells, (2) the time at which anoxic conditions were reached, and (3) a water quality index of the treated water related to the production of ammonia. We conclude that the rapidity of the technique confers a solid advantage over standard methods used for water quality analysis in laboratory and would permit the direct monitoring of the treatment performance on-board ships.

  2. Fuel cycle options for light water reactors and heavy water reactors. Proceedings of a technical committee meeting

    International Nuclear Information System (INIS)

    1999-11-01

    In the second half of the 20th century nuclear power has evolved from the research and development environment to an industry that supplies 16% of the world's electricity. By the end of 1997, over 8500 reactor-years of operating experience had been accumulated. Global environmental change, and the continuing increase in global energy supply required to provide increasing populations with an improving standard of living, make the contribution from nuclear energy even more important for the next century. For nuclear power to achieve its full potential and make its needed contribution, it must be safe, economical, reliable and sustainable. All of these factors can be enhanced by judicious choice and development of advanced fuel cycle options. The Technical Committee Meeting (TCM) on Fuel Cycle Options for Light Water Reactors and Heavy Water Reactors was hosted by Atomic Energy of Canada Limited (AECL) on behalf of the Canadian Government and was jointly conducted within the frame of activities of the IAEA International Working Group on Advanced Technologies for Light Water Reactors (IWG-LWR) and the IAEA International Working Group on Advanced Technologies for Heavy Water Reactors (IWG-HWR). The TCM provided the opportunity to have in-depth discussions on important technical topics which were highlighted in the International Symposium on Nuclear Fuel Cycle and Reactor Strategies: Adjusting to New Realities, held in Vienna, 3-6 June 1997. The main results and conclusions of the TCM were presented as input for discussion at the first meeting of the IAEA newly formed International Working Group on Fuel Cycle Options

  3. Recent performance experience with US light water reactor self-actuating safety and relief valves

    Energy Technology Data Exchange (ETDEWEB)

    Hammer, C.G.

    1996-12-01

    Over the past several years, there have been a number of operating reactor events involving performance of primary and secondary safety and relief valves in U.S. Light Water Reactors. There are several different types of safety and relief valves installed for overpressure protection of various safety systems throughout a typical nuclear power plant. The following discussion is limited to those valves in the reactor coolant systems (RCS) and main steam systems of pressurized water reactors (PWR) and in the RCS of boiling water reactors (BWR), all of which are self-actuating having a setpoint controlled by a spring-loaded disk acting against system fluid pressure. The following discussion relates some of the significant recent experience involving operating reactor events or various testing data. Some of the more unusual and interesting operating events or test data involving some of these designs are included, in addition to some involving a number of similar events and those which have generic applicability.

  4. Automated procedure for selection of optimal refueling policies for light water reactors

    International Nuclear Information System (INIS)

    Lin, B.I.; Zolotar, B.; Weisman, J.

    1979-01-01

    An automated procedure determining a minimum cost refueling policy has been developed for light water reactors. The procedure is an extension of the equilibrium core approach previously devised for pressurized water reactors (PWRs). Use of 1 1/2-group theory has improved the accuracy of the nuclear model and eliminated tedious fitting of albedos. A simple heuristic algorithm for locating a good starting policy has materially reduced PWR computing time. Inclusion of void effects and use of the Haling principle for axial flux calculations extended the nuclear model to boiling water reactors (BWRs). A good initial estimate of the refueling policy is obtained by recognizing that a nearly uniform distribution of reactivity provides low-power peaking. The initial estimate is improved upon by interchanging groups of four assemblies and is subsequently refined by interchanging individual assemblies. The method yields very favorable results, is simpler than previously proposed BWR fuel optimization schemes, and retains power cost as the objective function

  5. Disinfection of deionised water inoculated with enterobacter using ultra violet light

    International Nuclear Information System (INIS)

    Mathrani, M.

    2001-01-01

    For the first time the enterobacter, not the escherichia coli,was used as a model bacteria to asses the disinfection of microorganisms in water by UV (Ultra Violet) irradiation. The cell density of the liquid culture was followed by optical density of 1.837 at 600 nm on spectrometer. For the disinfection purpose, a laboratory scale batch reactor (10 cm wide, 20 cm long, and 10 cm height), containing 250 ml sterilised deionized water inoculated with enterobacter,was run under supra-band gap light (wavelength < 400 nm, peaking between 340 and 365 nm with a maximum of 350 nm). After carrying out seven batch experiments it is concluded that the complete inactivation of Enterobacter ( approx. equal to x 10/sup 6/ CFU/ml) in the water can be achieved by UV irradiation for 2 hours. (author)

  6. Neutron collar calibration for assay of LWR [light-water reactor] fuel assemblies

    International Nuclear Information System (INIS)

    Menlove, H.O.; Pieper, J.E.

    1987-03-01

    The neutron-coincidence collar is used for the verification of the uranium content in light-water reactor fuel assemblies. An AmLi neutron source is used to give an active interrogation of the fuel assembly to measure the 235 U content, and the 238 U content is verified from a passive neutron-coincidence measurement. This report gives the collar calibration data of pressurized-water reactor and boiling-water reactor fuel assemblies. Calibration curves and correction factors are presented for neutron absorbers (burnable poisons) and different fuel assembly sizes. The data were collected at Exxon Nuclear, Franco-Belge de Fabrication de Combustibles, ASEA-Atom, and other nuclear fuel fabrication facilities

  7. Neutronic investigations of an equilibrium core for a tight-lattice light water reactor

    International Nuclear Information System (INIS)

    Broeders, C.H.M.

    1992-01-01

    Calculation procedures and first results concerning the neutronic design of an equilibrium core of an advanced pressurized water reactor (APWR) with mixed oxide fuel in a compact light water moderated triangular lattice are presented. Principle and qualification of the cell burnup calculations with the KARBUS program are briefly discussed. The fuel assembly design with single control rod positions filled with control rod material or coolant water requires special transport theory calculations, which are performed with a one-dimensional supercell model. The macroscopic fuel assembly cross section data is collected in a special library to be used in a new calculational procedure, ARCOSI, for multi-cycle reactor core simulations. Its first application for a reference design resulted in an equilibrium configuration with moderator density reactivity coefficients which are satisfactory as regards safety. (orig.) [de

  8. Pigment specific in vivo light absorption of phytoplankton from estuarine, coastal and oceanic waters

    DEFF Research Database (Denmark)

    Stæhr, A.; Markager, S.; Sand-Jensen, K.

    2004-01-01

    The influence of phytoplankton photoacclimation and adaptation to natural growth conditions on the chlorophyll a-specific in vivo absorption coefficient (a* ph) was evaluated for samples collected in estuarine, coastal and oceanic waters. Despite an overall gradient in the physio......-chemical environment from estuaries, over coastal, to oceanic waters, no clear relationships were found between a* ph and the prevailing light, temperature, salinity and nutrient concentrations, indicating that short-term cellular acclimation was of minor importance for the observed variability in a* ph. The clear...... decline in a* ph from oceanic, over coastal, to estuarine waters was, however, strongly correlated with an increase in cell size and intracellular chlorophyll a (chl a) content of the phytoplankton, and a reduction of photosynthetic carotenoids relative to chl a. Variations in photoprotective carotenoids...

  9. Note: Three wavelengths near-infrared spectroscopy system for compensating the light absorbance by water

    Science.gov (United States)

    Bhutta, M. Raheel; Hong, Keum-Shik; Kim, Beop-Min; Hong, Melissa Jiyoun; Kim, Yun-Hee; Lee, Se-Ho

    2014-02-01

    Given that approximately 80% of blood is water, we develop a wireless functional near-infrared spectroscopy system that detects not only the concentration changes of oxy- and deoxy-hemoglobin (HbO and HbR) during mental activity but also that of water (H2O). Additionally, it implements a water-absorption correction algorithm that improves the HbO and HbR signal strengths during an arithmetic task. The system comprises a microcontroller, an optical probe, tri-wavelength light emitting diodes, photodiodes, a WiFi communication module, and a battery. System functionality was tested by means of arithmetic-task experiments performed by healthy male subjects.

  10. Improved correction methods for field measurements of particulate light backscattering in turbid waters.

    Science.gov (United States)

    Doxaran, David; Leymarie, Edouard; Nechad, Bouchra; Dogliotti, Ana; Ruddick, Kevin; Gernez, Pierre; Knaeps, Els

    2016-02-22

    Monte Carlo simulations are used to compute the uncertainty associated to light backscattering measurements in turbid waters using the ECO-BB (WET Labs) and Hydroscat (HOBI Labs) scattering sensors. ECO-BB measurements provide an accurate estimate of the particulate volume scattering coefficient after correction for absorption along the short instrument pathlength. For Hydroscat measurements, because of a longer photon pathlength, both absorption and scattering effects must be corrected for. As the standard (sigma) correction potentially leads to large errors, an improved correction method is developed then validated using field inherent and apparent optical measurements carried out in turbid estuarine waters. Conclusions are also drawn to guide development of future short pathlength backscattering sensors for turbid waters.

  11. Comparison of two thorium fuel cycles for use in light water prebreeder/breeder reactor systems (AWBA Development Program)

    International Nuclear Information System (INIS)

    Merriman, F.C.; McCoy, D.F.; Boyd, W.A.; Dwyer, J.R.

    1983-05-01

    Light water prebreeder/breeder conceptual reactor systems have been developed which have the potential to significantly improve the fuel utilization of present generation light water reactors. The purpose of this study is to describe and compare two possible types of thorium fuel cycles for use in these light water prebreeder and breeder concepts. The two types of thorium fuel cycles basically differ in the fuel rod design used in the prebreeder cores and the uranium isotopic concentration of fuel supplied to the breeder cores

  12. [Using Excess Activated Sludge Treated 4-Chlorophenol Contained Waste Water to Cultivate Chlorella vulgaris].

    Science.gov (United States)

    Wang, Lu; Chen, Xiu-rong; Yan, Long; He, Yi-xuan; Shi, Zhen-dong

    2015-04-01

    Using different rations of sludge extracts and supernate from 4-Chlorophenol (4-CP) simulated wastewater's excess sludge after centrifugation to cultivate the Chlorella vulgaris to achieve the goal of excess sludge utilization together with chlorella cultivating. The experiments were performed in 500 mL flasks with different rations of sludge extracts & BG-11 and supernate & BG-11 in a light growth chamber respectively. Number of algal cells, Chlorophyll, enzyme activity, oil and water total nitrogen (TN), total phosphorus (TP), total organic carbon (TOC), toxicity index were investigated. Result showed that the nutrition supplies and toxicity in the excess sludge were removed efficiently via Chlorella vulgaris, the removal rates of TN and TP were at least 40% and 90% respectively; After 10 days cultivation, the density growth of 50% sludge extracts was 20 times higher of the beginning while its chlorophyll content was lower than that of the blank group. Sludge extracts could promote the proliferation of algae, but were not conducive to the synthesis of chlorophyll. The quantity of SOD in per cell showed Chlorella vulgaris gave a positive response via stimulation from toxicant in sludge extracts and supernate. The best time for collecting chlorella vulgaris was the fifth day of cultivation, taking neutral oil accumulation as the evaluating indicator for its utilization combined with the removal of supplies and toxicity.

  13. Bioaccumulation of heavy metals and two organochlorine pesticides (DDT and BHC) in crops irrigated with secondary treated waste water.

    Science.gov (United States)

    Mishra, Virendra K; Upadhyay, Alka R; Tripathi, B D

    2009-09-01

    Four crop plants Oryza sativa (rice), Solanum melongena (brinjal), Spinacea oleracea (spinach) and Raphanus sativus (radish) were grown to study the impact of secondary treated municipal waste water irrigation. These plants were grown in three plots each of 0.5 ha, and irrigated with secondary treated waste water from a sewage treatment plant. Sludge from the same sewage treatment plant was applied as manure. Cultivated plants were analyzed for accumulation of heavy metals and pesticides. Results revealed the accumulation of six heavy metals cadmium (Cd), chromium (Cr), iron (Fe), copper (Cu), nickel (Ni), and zinc (Zn) as well as two pesticides [1,1-bis(p-chlorophenyl)-2,2,2-trichloroethane; DDT] and benzene hexa chloride (BHC). Order of the plants for the extent of bioaccumulation was S. oleracea > R. sativus > S. melongena > O. sativa. The study has shown the secondary treated waste water can be a source of contamination to the soil and plants.

  14. Biomimetic Water-Collecting Fabric with Light-Induced Superhydrophilic Bumps.

    Science.gov (United States)

    Wang, Yuanfeng; Wang, Xiaowen; Lai, Chuilin; Hu, Huawen; Kong, Yeeyee; Fei, Bin; Xin, John H

    2016-02-10

    To develop an efficient water-collecting surface that integrates both fast water-capturing and easy drainage properties is of high current interest for addressing global water issues. In this work, a superhydrophobic surface was fabricated on cotton fabric via manipulation of both the surface roughness and surface energy. This was followed by a subsequent spray coating of TiO2 nanosol that created light-induced superhydrophilic bumps with a unique raised structure as a result of the interfacial tension of the TiO2 nanosol sprayed on the superhydrophobic fiber surface. These raised TiO2 bumps induce both a wettability gradient and a shape gradient, synergistically accelerating water coalescence and water collection. The in-depth study revealed that the quantity and the distribution of the TiO2 had a significant impact on the final water collection efficiency. This inexpensive and facilely fabricated fabric biomimicks the desert beetle's back and spider silk, which are capable of fog harvesting without additional energy consumption.

  15. Reduction of organic trace compounds and fresh water consumption by recovery of advanced oxidation processes treated industrial wastewater.

    Science.gov (United States)

    Bierbaum, S; Öller, H-J; Kersten, A; Klemenčič, A Krivograd

    2014-01-01

    Ozone (O(3)) has been used successfully in advanced wastewater treatment in paper mills, other sectors and municipalities. To solve the water problems of regions lacking fresh water, wastewater treated by advanced oxidation processes (AOPs) can substitute fresh water in highly water-consuming industries. Results of this study have shown that paper strength properties are not impaired and whiteness is slightly impaired only when reusing paper mill wastewater. Furthermore, organic trace compounds are becoming an issue in the German paper industry. The results of this study have shown that AOPs are capable of improving wastewater quality by reducing organic load, colour and organic trace compounds.

  16. Performance comparison of sand and fine sawdust vermifilters in treating concentrated grey water for urban poor.

    Science.gov (United States)

    Adugna, Amare T; Andrianisa, Harinaivo A; Konate, Yacouba; Ndiaye, Awa; Maiga, Amadou H

    2015-01-01

    A comparative investigation was conducted for 10 months with sand and fine sawdust vermifilters and a control unit to treat concentrated grey water generated from a poor urban household in Ouagadougou, Burkina Faso. Each of the filters was made up of cylindrical DN200-PVC pipes and filled with 10 cm of gravel at the bottom. On top of the gravel layer, filter 1 (fully sand, F1) was completed with 40 cm of sand and 10 cm of fine sawdust, filter 2 (partially sand, F2) with 20 cm of sand and 30 cm of fine sawdust, respectively, and filter 3 (fully sawdust, F3) and 4 (control, F4) with 50 cm of fine sawdust only. Two hundred Eudrilus eugeniae earthworms were inoculated in each of the vermifilters. The vermifiltration system was supplied with grey water four times per day at a hydraulic loading rate of 64 L/m(2)/day on a batch basis. The removal efficiencies of biological oxygen demand, total chemical oxygen demand, and dissolved chemical oxygen demand (dCOD) by the vermifilters were 25-30% higher than the control, but little differences were observed in terms of total suspended solids and coliform removal efficiencies. Though there was no significant difference in the performance of the three vermifilters (p > 0.05), except for dCOD removal efficiency, the lifespan of F2 and F3 was longer than that of F1. Therefore, fine sawdust can substitute sand as a filter medium in vermifilters.

  17. Models of water imbibition in untreated and treated porous media validated by quantitative magnetic resonance imaging

    Science.gov (United States)

    Gombia, M.; Bortolotti, V.; Brown, R. J. S.; Camaiti, M.; Fantazzini, P.

    2008-05-01

    Fluid imbibition affects almost every activity that directly or indirectly involves porous media, including oil reservoir rocks, soils, building materials, and countless others, including biological materials. In this paper, magnetic resonance imaging (MRI) has been applied to study water imbibition in a porous medium, in which capillary properties are artificially changed. As a model system, samples of Lecce stone, a material of cultural heritage interest, were analyzed before and after treatment with a protective polymer (Silirain-50 or Paraloid PB72). By using MRI, we can visualize the presence of water inside each sample and measure the height z(t ) reached by the wetting front as a function of time during experiments of capillary absorption before and after treatment. The sorptivity S, defined as the initial slope of z versus t1/2, has been determined before treatment and through both treated and untreated faces after treatment. Very good fits to the data were obtained with theoretical and empirical models of absorption kinetics, starting from the Washburn model for capillary rise, adapted by others to homogeneous porous media, and modified by us for application to a sample having a thin low-permeability layer on either surface as a result of a treatment process. This gives us parameters to quantify the effects on imbibition of the changes in the capillary properties. It is known that the Paraloid treatment preferentially affects the larger pore channels and the Silirain the smaller, and our results show this and illustrate the roles played by the different classes of pore sizes.

  18. Levels and profiles of polychlorinated dibenzo-p-dioxin and dibenzofurans in raw and treated water from water treatment plants in Shenzhen, China.

    Science.gov (United States)

    Lu, Feina; Jiang, Yousheng; Wu, Dongting; Zhou, Jian; Li, Shengnong; Zhang, Jianqing

    2016-04-01

    Levels and profiles of polychlorinated dibenzo-p-dioxin and dibenzofurans (PCDD/Fs) were analyzed for the first time in raw and treated water from five water treatment plants in Shenzhen, South China. The average PCDD/Fs concentrations were 32.93 pg/L (0.057 pg international toxic equivalent quantity (I-TEQ)/L) and 0.64 pg/L (0.021 pg I-TEQ/L) in raw and treated water, respectively. The removal rate of PCDD/Fs in terms of mass concentration varied from 93.4% to 98.8%, whereas a negative removal rate was observed in one plant in terms of TEQ concentration. The PCDD/Fs concentration in raw water was lower than most of the published data from other countries and regions, and the PCDD/Fs concentration in treated water was below the Maximum Contaminants Level (MCL) of 30 pg/L for dioxin in drinking water set by the US EPA. Historical pentachlorophenol usage, local waste incineration and industrial emissions, as well as surface runoff or even soil erosion, might be the main sources for PCDD/F pollution in water. The daily intake of PCDD/Fs for local residents from drinking water was estimated to be 0.69 fg I-TEQ/kg/day, which is negligible compared with that from food consumption (1.23 pg WHO-TEQ/kg/day) in the local area. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. Water-light interaction: A novel pathway for multi hallmark therapy in cancer

    Directory of Open Access Journals (Sweden)

    Luis Santana-Blank

    2014-02-01

    Full Text Available Laser photobiomodulation (LPBM has been proposed as a multi-target (multi-hallmark therapy for cancer and other complex diseases based on an approach that aims to substitute and/or complement metabolic energy pathways through oxygen-dependent (e.g., cytochrome c oxidase (CcO and/or oxygen-independent (e.g., light-water interactions (e.g., F0-F1 motors mechanisms with critical signaling pathways in primarily aqueous media. Cellular and molecular bases for water-mediated, long-range, energy supplementation aimed at inducing and modulating physiologically reparative processes, including apoptosis, have been previously presented through a mechanism termed Photo Infrared Pulsed Biomodulation (PIPBM. Water’s role as an oscillator in LPBM has also been documented. These ideas were recently complemented by integrating the role of the quasi-crystalline exclusion zone (EZ described by Pollack as the fourth phase of water. This is retrospective analysis of experimental and clinical data using an infrared pulsed laser device (IPLD. It found photo-induced effects over the water dynamics of burned rat tissue monitored by 1H-NMR transverse relaxation times (1/T2, indicating significantly greater structuring of water. In addition, a microdensitometry study of T2 weighted tumor heterogeneities from a phase I clinical trial of the IPLD in patients with advanced neoplasias and an algorithm for tumor characterization indicated significantly increased structuring of water, possibly proving a photobiomodulation effect over the EZ associated with histologically-confirmed selective photo-induced tumor cell death. To the best of our knowledge, this is the first clinical demonstration of light-induced effects over the EZ. It supports our premise that LPBM can increase potential energy in the EZ, which then acts as a rechargeable electrolytic bio-battery for the external selective supplementation of the energy demand required for cellular work, signaling pathways and

  20. Concept of low pressure water cracking for hydrogen production in the conventional Light water reactor

    International Nuclear Information System (INIS)

    Lee, Jae Young; Lee, Bong Ju

    2006-01-01

    The global warnings associated with the global warming due to the flue gas from fossil fuel and with the unstable market of the fossil fuel have been expanding. As a solution, it has been widely accepted that hydrogen can be a good candidate for the future energy source. Hydrogen can be produced by splitting water, an abundant material in the earth, and no pollutants are produced during its combustion. Furthermore, it can produce electricity directly in the fuel cell. Therefore, transport industry is preparing the vehicles for the hydrogen fuel. The future society based on the hydrogen energy naturally needs the power station for the mass production of the hydrogen and distribution and storage systems

  1. Zeaxanthin and the Heat Dissipation of Excess Light Energy in Nerium oleander Exposed to a Combination of High Light and Water Stress.

    Science.gov (United States)

    Demmig, B; Winter, K; Krüger, A; Czygan, F C

    1988-05-01

    Upon termination of watering of plants of Nerium oleander exposed to high light, photochemical efficiency became reduced as leaf water content decreased. Evidence is presented that this type of photoinhibition reflects to a substantial degree radiationless dissipation of excitation energy, probably mediated by the carotenoid zeaxanthin. During the imposition of water stress, the zeaxanthin content of leaves increased at the expense of violaxanthin and beta-carotene as a water deficit developed over a period of several days. The increase in zeaxanthin content was linearly related to an increase in the rate of radiationless energy dissipation in the antenna chlorophyll as calculated from the characteristics of chlorophyll a fluorescence measured with a pulse amplitude modulated fluorometer at room temperature. The increase in the rate of radiationless dissipation was also linearly related to a decrease in PSII photochemical efficiency as indicated by the ratio of variable to maximum fluorescence. Leaves of well-watered shade plants of N. oleander exposed to strong light showed a similar increase in zeaxanthin content as sun leaves of the same species subjected to drought in strong light. Shade leaves possessed the same capacity as sun leaves to form zeaxanthin at the expense of both violaxanthin and beta-carotene. The resistance of this species to the destructive effects of excess light appears to be related to interconversions between beta-carotene and the three carotenoids of the xanthophyll cycle.

  2. FTIR Evidence of Changes in Carbon Associated with Hydrophobicity in Wildfire Affected Soils Treated with Elevated Temperature, Acid Snow Melt, or UV-Light

    Science.gov (United States)

    Jacobson, A. R.; Anderson, A. J.; van Miegroet, H.

    2009-12-01

    In a wild fire, organic volatile compounds from vegetation condense on soil particles forming a hydrophobic layer several centimeters below the soil surface. We studied the degradation of the hydrophobic layer in soils from two fire sites. One site is located in a montane woodland (Wood Camp, Logan Canyon, UT) that burned in 2006. The second site is located in an arid pinyon pine/juniper stand in Milford Flats, Beaver County, UT that burned in 2007. Both sites were sampled in 2008. In situ measurements of hydrophobicity demonstrated highly hydrophobic layers a few centimeters below the surface at both sites in contrast with unburned control sites, where hydrophobicity was observed at the surface but fell off sharply with depth. Samples of surface and subsurface soil were collected from the burned and unburned areas at both sites. Subsamples of all the soils were placed in microlysimeters, treated with acid snowmelt, elevated temperatures (30°C - 47°C), and UV light. After the treatments, the soils were air-dried and the surfaces analyzed for evidence of change in hydrophobicity using the drop test, oxidation of aromatic functional groups by cation exchange capacity (CEC), and the selective degradation of aliphatic functional groups associated with hydrophobicity by FTIR-ATR. Although results of the water drop penetration test suggest that simply wetting and air-drying the soils resulted in complete loss of hydrophobicity, the CEC results suggest that carbon oxidation occurred in the organic matter rich Wood Camp Soils. CEC results for the low carbon content Milford Flats soils were less clear. Analyses of peak heights in the range 4000 - 400 cm-1 demonstrate clear differences between the controlled and burned soils from the two sites and effects of all the treatments, particularly in the regions from 3020 to 2800 cm-1, corresponding to asymmetric and symmetric stretching vibrations of methyl and methylene groups associated with hydrophobicity. Peak height in this

  3. Ambient water and visible-light irradiation drive changes in graphene morphology, structure, surface chemistry, aggregation, and toxicity.

    Science.gov (United States)

    Hu, Xiangang; Zhou, Ming; Zhou, Qixing

    2015-03-17

    The environmental behaviors and risks associated with graphene have attracted considerable attention. However, the fundamental effects of ambient water and visible-light irradiation on the properties and toxicity of graphene remain unknown. This work revealed that hydration and irradiation result in the transformation of large-sheet graphene to long-ribbon graphene. The thickness of the treated graphene decreased, and oxides were formed through the generation of singlet oxygen. In addition, hydration and irradiation resulted in greater disorder in the graphene structure and in the expansion of the d-spacing of the structure due to the introduction of water molecules and modifications of the functional groups. Oxidative modifications with two-stage (fast and low) kinetics enhanced the number of negative surface charges on the graphene and enhanced graphene aggregation. The above property alterations reduced the nanotoxicity of graphene to algal cells by reducing the generation of reactive oxygen species, diminishing protein carbonylation and decreasing tail DNA. A comparative study using graphene oxide suggested that oxidative modifications could play an important role in inhibiting toxicological activity. This study provides a preliminary approach for understanding the environmental behaviors of graphene and avoids overestimating the risks of graphene in the natural environment.

  4. Start-up of a free water surface constructed wetland for treating olive mill wastewater

    Directory of Open Access Journals (Sweden)

    Michailides Michail

    2015-01-01

    Full Text Available An olive mill's existing evaporation pond was separated into five cells and transformed into a free water surface constructed wetland. The constructed wetland was used as a post-treatment stage for olive mill wastewater (OMW. Wastewater was previously treated by an aerobic trickling filter. The influent concentrations in the constructed wetland were 27400 mg.L-1, 4800 mg.L-1, 105 mg.L-1 and 770 mg.L-1 for COD, phenols, ortho-phosphate and TKN, respectively. Despite the rather high influent concentrations, the performance of the constructed wetland was very good since after the 60-day start-up operation period it achieved removal rates of about 94%, 95%, 95% and 98% for COD, phenols, ortho-phosphate and TKN, respectively. The major pollutant removal processes can be attributed to both biological processes occurring in the wetland and photo-oxidation. Laboratory-scale experiments with OMW from fifth cell of the wetland revealed that the net contribution of photo-oxidation after 112 hours of simulated solar radiation at 765 W/m2 (i.e. about 38 days of sunlight irradiation was 18% and 31% removal for COD and phenols, respectively. In the constructed wetland, the total removal reached 81% and 86% for COD and phenols, respectively, for the same time period (38 days.

  5. Chlorinated and ultraviolet radiation -treated reclaimed irrigation water is the source of Aeromonas found in vegetables used for human consumption.

    Science.gov (United States)

    Latif-Eugenín, Fadua; Beaz-Hidalgo, Roxana; Silvera-Simón, Carolina; Fernandez-Cassi, Xavi; Figueras, María J

    2017-04-01

    Wastewater is increasingly being recognized as a key water resource, and reclaimed water (or treated wastewater) is used for irrigating vegetables destined for human consumption. The aim of the present study was to determine the diversity and prevalence of Aeromonas spp. both in reclaimed water used for irrigation and in the three types of vegetables irrigated with that water. Seven of the 11 (63.6%) samples of reclaimed water and all samples of vegetables were positive for the presence of Aeromonas. A total of 216 Aeromonas isolates were genotyped and corresponded to 132 different strains that after identification by sequencing the rpoD gene belonged to 10 different species. The prevalence of the species varied depending on the type of sample. In the secondary treated reclaimed water A. caviae and A. media dominated (91.4%) while A. salmonicida, A. media, A. allosaccharophila and A. popoffii represented 74.0% of the strains in the irrigation water. In vegetables, A. caviae (75.0%) was the most common species, among which a strain isolated from lettuce had the same genotype (ERIC pattern) as a strain recovered from the irrigation water. Furthermore, the same genotype of the species A. sanarellii was recovered from parsley and tomatoes demonstrating that irrigation water was the source of contamination and confirming the risk for public health. Copyright © 2017 Elsevier Inc. All rights reserved.

  6. Chemical aspects of fission product transport in the primary circuit of a light water reactor

    International Nuclear Information System (INIS)

    Bowsher, B.R.; Dickinson, S.; Nichols, A.L.; Ogden, J.S.; Potter, P.E.

    1985-01-01

    The transport and fission products in the primary circuit of a light water reactor are of fundamental importance in assessing the consequences of severe accidents. Recent experimental studies have concentrated upon the behaviour of simulant fission product species such as caesium iodide, caesium hydroxide and tellurium, in terms of their vapour deposition characteristics onto metals representative of primary circuit materials. An induction furnace has been used to generate high-density/structural materials aerosols for subsequent analysis, and similar equipment has been incorporated into a glove-box to study lightly-irradiated UO/sub 2/ clad in Zircaloy. Analytical techniques are being developed to assist in the identification of fission product chemical species released from the fuel at temperatures from 1000 to 2500 0 C. Matrix isolation-infrared spectroscopy has been used to identify species in the vapour phase, and specific data using this technique are reported

  7. Chemical aspects of fission product transport in the primary circuit of a light water reactor

    International Nuclear Information System (INIS)

    Bowsher, B.R.; Dickinson, S.; Nichols, A.L.; Ogden, J.S.; Potter, P.E.

    1985-01-01

    The transport and deposition of fission products in the primary circuit of a light water reactor are of fundamental importance in assessing the consequences of severe accidents. Recent experimental studies have concentrated upon the behavior of simulant fission product species such as cesium iodide, cesium hydroxide and tellurium, in terms of their vapor deposition characteristics onto metals representative of primary circuit materials. An induction furnace has been used to generate high density/structural materials aerosols for subsequent analysis, and similar equipment has been incorporated into a glove-box to study lightly-irradiated UO 2 clad in Zircaloy. Analytical techniques are being developed to assist in the identification of fission product chemical species released from the fuel at temperatures from 1000 to 2500 0 C. Matrix isolation-infrared spectroscopy has been used to identify species in the vapor phase, and specific data using this technique are reported

  8. Assessing the consistency and microbiological effectiveness of household water treatment practices by urban and rural populations claiming to treat their water at home: a case study in Peru.

    Directory of Open Access Journals (Sweden)

    Ghislaine Rosa

    Full Text Available Household water treatment (HWT can improve drinking water quality and prevent disease if used correctly and consistently by vulnerable populations. Over 1.1 billion people report treating their water prior to drinking it. These estimates, however, are based on responses to household surveys that may exaggerate the consistency and microbiological performance of the practice-key factors for reducing pathogen exposure and achieving health benefits. The objective of this study was to examine how HWT practices are actually performed by households identified as HWT users, according to international monitoring standards.We conducted a 6-month case study in urban (n = 117 households and rural (n = 115 households Peru, a country in which 82.8% of households report treating their water at home. We used direct observation, in-depth interviews, surveys, spot-checks, and water sampling to assess water treatment practices among households that claimed to treat their drinking water at home. While consistency of reported practices was high in both urban (94.8% and rural (85.3% settings, availability of treated water (based on self-report at time of collection was low, with 67.1% and 23.0% of urban and rural households having treated water at all three sampling visits. Self-reported consumption of untreated water in the home among adults and children <5 was common and this was corroborated during home observations. Drinking water of self-reported users was significantly better than source water in the urban setting and negligible but significantly better in the rural setting. However, only 46.3% and 31.6% of households had drinking water <1 CFU/100 mL at all follow-up visits.Our results raise questions about the usefulness of current international monitoring of HWT practices and their usefulness as a proxy indicator for drinking water quality. The lack of consistency and sub-optimal microbiological effectiveness also raises questions about the potential

  9. Results of an aging-related failure survey of light water safety systems and components

    International Nuclear Information System (INIS)

    Meale, B.M.; Satterwhite, D.G.; MacDonald, P.E.

    1988-01-01

    The collection and evaluation of operating experience data are necessary in determining the effects of aging on the safety of operating nuclear plants. This paper presents the final results of a two-year research effort evaluating aging impacts on components in light water reactor systems. This research was performed as a part of the Nuclear Plant Aging Research program, sponsored by the US Nuclear Regulatory Commission. Two unique types of data analyses were performed. In the first, an aging-survey study, aging-related failure data for fifteen light water reactor systems were obtained from the Nuclear Plant Reliability Data System (NPRDS). These included safety, support, and power conversion systems. A computerized sort of these records classified each record into one of five generic categories, based on the utility's choice of the failure's NPRDS cause category. Systems and components within the systems that were most affected by aging were identified. In the second analysis, information on aging-related reported causes of failures was evaluated for component failures reported to NPRDS for auxiliary feedwater, high pressure injection, service water, and Class 1E electrical power distribution systems. 3 refs., 13 figs., 4 tabs

  10. Intrinsic climate dependency of ecosystem light and water-use-efficiencies across Australian biomes

    International Nuclear Information System (INIS)

    Shi, Hao; Li, Longhui; Eamus, Derek; Cleverly, James; Huete, Alfredo; Yu, Qiang; Beringer, Jason; Van Gorsel, Eva; Hutley, Lindsay

    2014-01-01

    The sensitivity of ecosystem gross primary production (GPP) to availability of water and photosynthetically active radiation (PAR) differs among biomes. Here we investigated variations of ecosystem light-use-efficiency (eLUE: GPP/PAR) and water-use-efficiency (eWUE: GPP/evapotranspiration) among seven Australian eddy covariance sites with differing annual precipitation, species composition and temperature. Changes to both eLUE and eWUE were primarily correlated with atmospheric vapor pressure deficit (VPD) at multiple temporal scales across biomes, with minor additional correlations observed with soil moisture and temperature. The effects of leaf area index on eLUE and eWUE were also relatively weak compared to VPD, indicating an intrinsic dependency of eLUE and eWUE on climate. Additionally, eLUE and eWUE were statistically different for biomes between summer and winter, except eWUE for savannas and the grassland. These findings will improve our understanding of how light- and water-use traits in Australian ecosystems may respond to climate change. (letter)

  11. Light Water Reactor Sustainability Program Status of Silicon Carbide Joining Technology Development

    Energy Technology Data Exchange (ETDEWEB)

    Bragg-Sitton, Shannon M. [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2013-09-01

    Advanced, accident tolerant nuclear fuel systems are currently being investigated for potential application in currently operating light water reactors (LWR) or in reactors that have attained design certification. Evaluation of potential options for accident tolerant nuclear fuel systems point to the potential benefits of silicon carbide (SiC) relative to Zr-based alloys, including increased corrosion resistance, reduced oxidation and heat of oxidation, and reduced hydrogen generation under steam attack (off-normal conditions). If demonstrated to be applicable in the intended LWR environment, SiC could be used in nuclear fuel cladding or other in-core structural components. Achieving a SiC-SiC joint that resists corrosion with hot, flowing water, is stable under irradiation and retains hermeticity is a significant challenge. This report summarizes the current status of SiC-SiC joint development work supported by the Department of Energy Light Water Reactor Sustainability Program. Significant progress has been made toward SiC-SiC joint development for nuclear service, but additional development and testing work (including irradiation testing) is still required to present a candidate joint for use in nuclear fuel cladding.

  12. In vitro function of platelets treated with ultraviolet C light for pathogen inactivation: a comparative study with nonirradiated and gamma-irradiated platelets.

    Science.gov (United States)

    Tynngård, Nahreen; Trinks, Marie; Berlin, Gösta

    2015-06-01

    During storage of platelet concentrates (PCs) replication of contaminating pathogens might occur, which can be prevented by various pathogen inactivation (PI) methods using photoactive substances in combination with ultraviolet (UV) light. A new method uses only UVC light for PI without photoactive substances. This study evaluates the in vitro function, including hemostatic properties (clot formation and elasticity), of platelets (PLTs) treated with UVC light. A PC with 35% plasma and 65% PLT additive solution (SSP+) was prepared from five buffy coats. Three PCs were pooled and divided into 3 units. One unit was used as a nonirradiated control, the second was a gamma-irradiated control, and the third unit was treated with UVC light. In vitro variables including analysis of coagulation by free oscillation rheometry were analyzed on Days 1, 5, and 7 of storage. Ten units in each group were investigated. Swirling was well preserved, and the pH level was higher than the reference limit (6.4) during storage of PLTs in all groups. Glycolysis and PLT activation were higher for UVC-treated PLTs but the clot-forming capacity was unaffected. However, immediately after UVC treatment, the clot elastic properties were slightly affected. Hypotonic shock response decreased immediately after UVC treatment but recovered partly during the storage period. UVC treatment affected the in vitro properties, but PLT quality and storage stability were well preserved for up to 7 days, and the in vitro hemostatic capacity of UVC-treated PLTs was only minimally altered. The clinical relevance of these changes needs to be evaluated in controlled trials. © 2014 AABB.

  13. Energy Research Advisory Board, Civilian Nuclear Power Panel: Subpanel 1 report, Light water reactor utilization and improvement: Volume 2

    International Nuclear Information System (INIS)

    1986-10-01

    The Secretary of Energy requested that the Office of Nuclear Energy prepare a strategic national plan that outlines the Department's role in the future development of civilian nuclear power and that the Energy Research Advisory Board establish an ad hoc panel to review and comment on this plan. The Energy Research Advisory Board formed a panel for this review and three subpanels were formed. One subpanel was formed to address the institutional issues surrounding nuclear power, one on research and development for advanced nuclear power plants and a third subpanel on light water reactor utilization and improvement. The subpanel on light water reactors held two meetings at which representatives of the DOE, the NRC, EPRI, industry and academic groups made presentations. This is the report of the subpanel on light water reactor utilization and improvement. This report presents the subpanel's assessment of initiatives which the Department of Energy should undertake in the national interest, to develop and support light water reactor technologies

  14. Guidance for Developing Principal Design Criteria for Advanced (Non-Light Water) Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Holbrook, Mark [Idaho National Lab. (INL), Idaho Falls, ID (United States); Kinsey, Jim [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2015-03-01

    In July 2013, the US Department of Energy (DOE) and US Nuclear Regulatory Commission (NRC) established a joint initiative to address a key portion of the licensing framework essential to advanced (non-light water) reactor technologies. The initiative addressed the “General Design Criteria for Nuclear Power Plants,” Appendix A to10 Code of Federal Regulations (CFR) 50, which were developed primarily for light water reactors (LWRs), specific to the needs of advanced reactor design and licensing. The need for General Design Criteria (GDC) clarifications in non-LWR applications has been consistently identified as a concern by the industry and varied stakeholders and was acknowledged by the NRC staff in their 2012 Report to Congress1 as an area for enhancement. The initiative to adapt GDC requirements for non-light water advanced reactor applications is being accomplished in two phases. Phase 1, managed by DOE, consisted of reviews, analyses and evaluations resulting in recommendations and deliverables to NRC as input for NRC staff development of regulatory guidance. Idaho National Laboratory (INL) developed this technical report using technical and reactor technology stakeholder inputs coupled with analysis and evaluations provided by a team of knowledgeable DOE national laboratory personnel with input from individual industry licensing consultants. The DOE national laboratory team reviewed six different classes of emerging commercial reactor technologies against 10 CFR 50 Appendix A GDC requirements and proposed guidance for their adapted use in non-LWR applications. The results of the Phase 1 analysis are contained in this report. A set of draft Advanced Reactor Design Criteria (ARDC) has been proposed for consideration by the NRC in the establishment of guidance for use by non-LWR designers and NRC staff. The proposed criteria were developed to preserve the underlying safety bases expressed by the original GDC, and recognizing that advanced reactors may take

  15. Environmentally assisted cracking in light water reactors. Semiannual progress report, January 1996--June 1996

    International Nuclear Information System (INIS)

    Chopra, O.K.; Chung, H.M.; Gruber, E.E.

    1997-05-01

    This report summarizes work performed by Argonne National Laboratory on fatigue and environmentally assisted cracking (EAC) in light water reactors from January 1996 to June 1996. Topics that have been investigated include (a) fatigue of carbon, low-alloy, and austenitic stainless steels (SSs) used in reactor piping and pressure vessels, (b) irradiation-assisted stress corrosion cracking of Type 304 SS, and (c) EAC of Alloys 600 and 690. Fatigue tests were conducted on ferritic and austenitic SSs in water that contained various concentrations of dissolved oxygen (DO) to determine whether a slow strain rate applied during various portions of a tensile-loading cycle are equally effective in decreasing fatigue life. Slow-strain-rate-tensile tests were conducted in simulated boiling water reactor (BWR) water at 288 degrees C on SS specimens irradiated to a low fluence in the Halden reactor and the results were compared with similar data from a control-blade sheath and neutron-absorber tubes irradiated in BWRs to the same fluence level. Crack-growth-rate tests were conducted on compact-tension specimens from several heats of Alloys 600 and 690 in air and high-purity, low-DO water. 83 refs., 60 figs., 14 tabs

  16. Environmentally assisted cracking in light water reactors. Semiannual progress report, January 1996--June 1996

    Energy Technology Data Exchange (ETDEWEB)

    Chopra, O.K.; Chung, H.M.; Gruber, E.E. [and others

    1997-05-01

    This report summarizes work performed by Argonne National Laboratory on fatigue and environmentally assisted cracking (EAC) in light water reactors from January 1996 to June 1996. Topics that have been investigated include (a) fatigue of carbon, low-alloy, and austenitic stainless steels (SSs) used in reactor piping and pressure vessels, (b) irradiation-assisted stress corrosion cracking of Type 304 SS, and (c) EAC of Alloys 600 and 690. Fatigue tests were conducted on ferritic and austenitic SSs in water that contained various concentrations of dissolved oxygen (DO) to determine whether a slow strain rate applied during various portions of a tensile-loading cycle are equally effective in decreasing fatigue life. Slow-strain-rate-tensile tests were conducted in simulated boiling water reactor (BWR) water at 288{degrees}C on SS specimens irradiated to a low fluence in the Halden reactor and the results were compared with similar data from a control-blade sheath and neutron-absorber tubes irradiated in BWRs to the same fluence level. Crack-growth-rate tests were conducted on compact-tension specimens from several heats of Alloys 600 and 690 in air and high-purity, low-DO water. 83 refs., 60 figs., 14 tabs.

  17. Environmentally assisted cracking in light water reactors. Semiannual report July 1996--December 1996

    Energy Technology Data Exchange (ETDEWEB)

    Chopra, O.K.; Chung, H.M.; Gavenda, D.J. [Argonne National Lab., IL (United States)] [and others

    1997-10-01

    This report summarizes work performed by Argonne National Laboratory on fatigue and environmentally assisted cracking (EAC) in light water reactors from July 1996 to December 1996. Topics that have been investigated include (a) fatigue of carbon, low-alloy, and austenitic stainless steels (SSs) used in reactor piping and pressure vessels, (b) irradiation-assisted stress corrosion cracking of Type 304 SS, (c) EAC of Alloy 600, and (d) characterization of residual stresses in welds of boiling water reactor (BWR) core shrouds by numerical models. Fatigue tests were conducted on ferritic and austenitic SSs in water that contained various concentrations of dissolved oxygen to determine whether a slow strain rate applied during various portions of a tensile-loading cycle are equally effective in decreasing fatigue life. Slow-strain-rate-tensile tests were conducted in simulated BWR water at 288 C on SS specimens irradiated to a low fluence in the Halden reactor and the results were compared with similar data from a control-blade sheath and neutron-absorber tubes irradiated in BWRs to the same fluence level. Crack-growth-rate tests were conducted on compact-tension specimens from a low-carbon content heat of Alloy 600 in high-purity oxygenated water at 289 C. Residual stresses and stress intensity factors were calculated for BWR core shroud welds.

  18. An example of treated waste water use for soil irrigation in the SAFIR project.

    Science.gov (United States)

    Cary, L.; Jovanovic, Z.; Stikic, R.; Blagojevic, S.; Kloppmann, W.

    2009-04-01

    The safe use of treated domestic wastewater for irrigation needs to address the risks for humans (workers, exposed via contact with irrigation water, soil, crops and food, consumers, exposed via ingestion of fresh and processed food), for animals (via ingestion of crops on soil), for the crops and agricultural productivity (via salinity and trace element uptake), for soil (via accumulation or release of pollutants) as well as for surface, groundwaters and the associated ecosystems (via runoff and infiltration, Kass et al., 2005, Bouwer, 2000). In this context, the European FP6 SAFIR project (Safe and High Quality Food Production using Low Quality Waters and Improved Irrigation Systems and Management) investigates the geochemical quality of the root zone soil, knowing it is the main transit and storage compartment for pollutants. The type of reaction (sorption, co-precipitation…) and the reactive mineral phases also determine the availability of trace elements for the plant and determine the passage towards crops and products. Reactions of the infiltrating water with the soil solid phase are important for the solute cycling, temporary fixation and remobilisation of trace pollutants. Therefore the soil water quality was directly or indirectly assessed. Direct measurements of soil water were made through porous cups. The experiments were carried out during the growing season of 2006, 2007 and 2008 in a vegetable commercial farm, located at 10 km north of Belgrade. The soil is silty clayey, and developed on alluvial deposits. It was classified as humogley according to USDA Soil Classification. The climate of the field side is a continental type with hot and dry summers and cold and rainy winters. As in the rest of Serbia, farm suffers from water deficits during the main growing season. The initial soil quality was assessed through a sampling campaign before the onset of first year irrigation; the soil quality was then monitored throughout three years. Soil sampling

  19. Normal and compact spent fuel storage in light water reactor power plants

    International Nuclear Information System (INIS)

    Kuenel, R.R.

    1978-01-01

    The compact storage of light water reactor spent fuel is a safe, cheap and reliable contribution towards overcoming the momentarily existing shortage in spent fuel reprocessing. The technical concept is described and physical behaviour discussed. The introduction of compact storage racks in nuclear power plants increases the capacity from 100 to about 240 %. The increase in decay heat is not more than about 14%, the increase in activity inventory and hazard potential does not exceed 20%. In most cases the existing power plant equipment fulfils the new requirements. (author)

  20. Two-phase coolant pump model of pressurized light water nuclear reactors

    International Nuclear Information System (INIS)

    Santos, G.A. dos; Freitas, R.L.

    1990-01-01

    The two-phase coolant pump model of pressurized light water nuclear reactors is an important point for the loss of primary coolant accident analysis. The homologous curves set up the complete performance of the pump and are input for accidents analysis thermal-hydraulic codes. This work propose a mathematical model able to predict the two-phase homologous curves where it was incorporated geometric and operational pump condition. The results were compared with the experimental tests data from literature and it has showed a good agreement. (author)

  1. Comparison between Nuclear Data Libraries of Different Density of Data for H in Light Water

    International Nuclear Information System (INIS)

    Torres, Lourdes; Gillette, Victor

    2003-01-01

    We introduce the results of comparison between nuclear data libraries at different density of data.Nuclear data libraries were produced for hydrogen (H) in light water at different density of data.These libraries were produced using the NJOY nuclear data processing system.With this code we produce pointwise cross sections and related quantities, in the ENDF format, and in the ACE format for MCNP.Experimental neutron spectrum was compared with MCNP4C simulations, based on the produced libraries and calculation time

  2. Light water reactor - pressure-vessel neutron spectrometry with solid state track recorders

    International Nuclear Information System (INIS)

    Ruddy, F.H.; Gold, R.; Roberts, J.H.

    1982-01-01

    Solid State Track Recorders have been used to measure absolute fission rates in the Light Water Reactor - Pressure Vessel Simulator at the Oak Ridge Pool Critical Assembly. Measurements were made in the 12/13 configuration with 237 Np, 238 U, and 235 U at the TSF, TSB, PVF, 1/4 T, 1/2 T, and 3/4 T locations. To avoid relative power normalization uncertainties, all locations were measured simultaneously in a single run for each isotope. Comparison of SSTR results are made with the results of measurements performed by NBS and CEN/SCK using benchmark referenced fission chambers and with the trends of theoretical calculations

  3. Verification of calculational methods for light water high converter reactors by critical experiments

    International Nuclear Information System (INIS)

    Berger, H.D.

    1988-01-01

    Calculational results relevant to the physics characteristics of PuO 2 /UO 2 -fueled light water high converter reactors (LWHCR) are discussed in the context of three particular codes and their associated data libraries, viz. WIMS/D, KARBUS (GRUCAH) and SPEKTRA. Analysis of various critical experiments - from the PROTEUS-LWHCR Phase I and Phase II programmes in particular - has demonstrated the importance of having a representative and comprehensive integral data base for identifying specific shortcomings in the calculational tools employed. (orig./DG)

  4. Prospects for plutonium recycling in light-water reactors in the European Communities

    International Nuclear Information System (INIS)

    Haijtink, B.

    1977-01-01

    On the basis of a forecast on nuclear power installation programmes and spent nuclear fuel reprocessing capacities in the European Community, an assessment has been made of the developmnt of the plutonium handling industry up to the year 1990. Data on plutonium recovered in the reprocessing plants, requirements for fuelling the fast-breeder reactors and the remaining stockpile have been evaluated. A possible strategy for recycling the plutonium surplus in light-water reactors has been developed and its effects as regards saving on requirements for natural uranium and enrichment services have been estimated

  5. Siting of light-water reactor power plants in the Federal Republic of Germany

    International Nuclear Information System (INIS)

    Kohler, H.A.G.

    1975-01-01

    The nuclear power plant site requirements formulated for environment protection in Germany allow nuclear power plants to be built at any site provided these requirements are duly taken into account in preparing and monitoring the site and in the design of the proposed power plant. After a brief discussion of light water reactor power plant sites, prevailing practice in site planning, site selection criteria, licensing procedure and used criteria, rules and guidelines, this paper reports on some considerations taken into account by the expert advisers and by the licensing authorities and future site planning. (orig.) [de

  6. Study of High Fluence Radiation-induced Swelling and Hardening under Light Water Reactor Conditions

    Energy Technology Data Exchange (ETDEWEB)

    Golubov, Stanislav I. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Barashev, Alexander V. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Stoller, Roger E. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2016-09-01

    This report documents a comprehensive model that has been developed to enable simulations of microstructural evolution under the irradiation conditions typical of light water reactor (LWR) internal components. The model, which accounts cascade production of point defects and vacancy, interstitial faulted dislocation loops, interstitial clusters migrating one-dimensionally and the evolution of the network dislocation structure, has been parameterized to account damage accumulation in austenitic stainless steels. Nucleation and growth of an ensemble of cavities is based on accounting the residual and produced by irradiation He atoms and existence of the dislocation and production biases. Additional applications and potential future developments for the model are also discussed.

  7. Evaluation of Proactive Management Issues Associated with Materials Aging in Light Water Reactors

    International Nuclear Information System (INIS)

    Shoji, T.; Takeda, Y.; Kuniya, J.

    2012-01-01

    A Proactive Materials Degradation Management (PMDM) project has been carried out at the Fracture Research Institute (FRI), Tohoku University for 4 years, as a part of a Nuclear Industries Safety Agency (NISA) project that was formed in 2007 to define an Aging Management Program that addresses unexpected structural material failures in Light Water Reactors (LWRs). Such a program required, therefore, the development of a life prediction capability for specific combinations of degradation modes, structural materials, and reactor components. In this paper, the research subjects needed to predict quantitatively aging degradation phenomena in LWR structural materials are introduced. (author)

  8. LWR (light water reactor) pressure vessel irradiation surveillance dosimetry. Quarterly progress report, January-March 1980

    International Nuclear Information System (INIS)

    Guthrie, G.L.; McElroy, W.N.

    1980-12-01

    The report describes progress made in the Light Water Reactor Pressure Vessel Irradiation Surveillance Dosimetry Program during the reporting period. The primary objective of the multi-laboratory program is to prepare an updated and improved set of dosimetry, damage correlation, and associated reactor analysis ASTM Standards for LWR-PV irradiation surveillance programs. Supporting this objective are a series of analytical and experimental validation and calibration studies in 'Standard, Reference, and Controlled Environment Benchmark Fields', reactor 'Test Regions', and operating power reactor 'Surveillance Positions'

  9. Environment sensitive cracking in pressure boundary materials of light water reactors

    International Nuclear Information System (INIS)

    Hanninen, H.; Aho-Mantila, I.; Torronen, K.

    1987-08-01

    A review of the various forms of environment sensitive cracking in pressure boundary materials of light water reactors is presented. The available methods and the most promising future possibilities of preventive maintenance to counteract the environmental degradation are evaluated. Environment sensitive cracking is considered from the metallurgical, mechanical and environmental point of view. The main emphasis is on intergranular stress corrosion cracking of austenitic stainless steels and high strength Ni-base alloys as well as on corrosion fatigue of low alloy and stainless steels. Additionally, some general ideas on how to predict, reduce, monitor or eliminate environment sensitive cracking in service are presented

  10. Reactor and turbine building layout of the high performance light water reactor

    International Nuclear Information System (INIS)

    Bittermann, D.

    2010-01-01

    Based on the information generated within the European funded project ''High Per-formance Light Water Reactor Phase 2'', a general plant layout has been developed. The central building is the reactor building, in which the containment and safety sys-tems are located. The reactor building is with app. 90.000 m 3 considerably smaller compared to other BWR buildings, thus providing a huge potential for cost savings. The turbine building with app 250,000 m 3 is of approximately the same size like for existing BWRs. (orig.)

  11. Light-water-reactor coupled neutronic and thermal-hydraulic codes

    International Nuclear Information System (INIS)

    Diamond, D.J.

    1982-01-01

    An overview is presented of computer codes that model light water reactor cores with coupled neutronics and thermal-hydraulics. This includes codes for transient analysis and codes for steady state analysis which include fuel depletion and fission product buildup. Applications in nuclear design, reactor operations and safety analysis are given and the major codes in use in the USA are identified. The neutronic and thermal-hydraulic methodologies and other code features are outlined for three steady state codes (PDQ7, NODE-P/B and SIMULATE) and four dynamic codes (BNL-TWIGL, MEKIN, RAMONA-3B, RETRAN-02). Speculation as to future trends with such codes is also presented

  12. Research of application of new material to light water reactor components

    International Nuclear Information System (INIS)

    Mihara, Tanetoyo

    1992-01-01

    Advanced Nuclear Equipment Research Institute (ANERI) has been doing the research to apply the new material including metal, fine ceramics and high polymer which were developed and applied in other industries to components and parts of light water reactor for the purpose of Improvement of reliability of components, improvement of efficiency of periodic inspection, improvement of repair and reduction of radiation exposure of worker. This project started upon the sponsorship of Ministry of International Trade and Industry (MITI) by the schedule of FY1985-FY1993 (9 years) and effective results has been obtained. (author)

  13. Development of Advanced High Uranium Density Fuels for Light Water Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Blanchard, James [Univ. of Wisconsin, Madison, WI (United States); Butt, Darryl [Boise State Univ., ID (United States); Meyer, Mitchell [Idaho National Lab. (INL), Idaho Falls, ID (United States); Xu, Peng [Westinghouse Electric Corporation, Pittsburgh, PA (United States)

    2016-02-15

    This work conducts basic materials research (fabrication, radiation resistance, thermal conductivity, and corrosion response) on U3Si2 and UN, two high uranium density fuel forms that have a high potential for success as advanced light water reactor (LWR) fuels. The outcome of this proposed work will serve as the basis for the development of advance LWR fuels, and utilization of such fuel forms can lead to the optimization of the fuel performance related plant operating limits such as power density, power ramp rate and cycle length.

  14. Terms and definitions of conversion ratio for High Conversion Light Water Reactor

    International Nuclear Information System (INIS)

    Shimada, Shoichiro

    1990-01-01

    Conversion ratio is an important index as a term to indicate fuel source utilization. It was used to indicate breeding ratio in FBR and its definition was discussed in the paper. Studies for High Conversion Light Water Reactor have been started and the conversion ratio has been used as an index of fuel utilization. Its definition is not unique and there are some confusions among the papers. In this data the author tries to review various definitions of conversion ratio and clarify their physical meaning and its relation among the definitions. (author)

  15. Energy-analysis of the total nuclear energy cycle based on light water reactors

    International Nuclear Information System (INIS)

    Kistemaker, J.

    1975-01-01

    The energy economy of the total nuclear energy cycle is investigated. Attention is paid to the importance of fossil fuel saving by using nuclear energy. The energy analysis is based on the construction and operation of power plants with an electric output of 1000MWe. Light water moderated reactors with a 2.7 - 3.2% enriched uranium core are considered. Additionally, the whole fuel cycle including ore winning and refining, enrichment and fuel element manufacturing and reprocessing has been taken into account. Neither radioactive waste storage problems nor safety problems related to the nuclear energy cycle and safeguarding have been dealt with, as exhaustive treatments can be found elswhere

  16. Light-water-reactor coupled neutronic and thermal-hydraulic codes

    Energy Technology Data Exchange (ETDEWEB)

    Diamond, D.J.

    1982-01-01

    An overview is presented of computer codes that model light water reactor cores with coupled neutronics and thermal-hydraulics. This includes codes for transient analysis and codes for steady state analysis which include fuel depletion and fission product buildup. Applications in nuclear design, reactor operations and safety analysis are given and the major codes in use in the USA are identified. The neutronic and thermal-hydraulic methodologies and other code features are outlined for three steady state codes (PDQ7, NODE-P/B and SIMULATE) and four dynamic codes (BNL-TWIGL, MEKIN, RAMONA-3B, RETRAN-02). Speculation as to future trends with such codes is also presented.

  17. Microencapsulated fuel technology for commercial light water and advanced reactor application

    International Nuclear Information System (INIS)

    Terrani, Kurt A.; Snead, Lance L.; Gehin, Jess C.

    2012-01-01

    The potential application of microencapsulated fuels to light water reactors (LWRs) has been explored. The specific fuel manifestation being put forward is for coated fuel particles embedded in silicon carbide or zirconium metal matrices. Detailed descriptions of these concepts are presented, along with a review of attributes, potential benefits, and issues with respect to their application in LWR environments, specifically from the standpoints of materials, neutronics, operations, and economics. Preliminary experiment and modeling results imply that with marginal redesign, significant gains in operational reliability and accident response margins could be potentially achieved by replacing conventional oxide-type LWR fuel with microencapsulated fuel forms.

  18. Quantifying the radiant exposure and effective dose in patients treated for actinic keratoses with topical photodynamic therapy using daylight and LED white light

    Science.gov (United States)

    Manley, M.; Collins, P.; Gray, L.; O’Gorman, S.; McCavana, J.

    2018-02-01

    Daylight photodynamic therapy (dl-PDT) is as effective as conventional PDT (c-PDT) for treating actinic keratoses but has the advantage of reducing patient discomfort significantly. Topical dl-PDT and white light-PDT (wl-PDT) differ from c-PDT by way of light sources and methodology. We measured the variables associated with light dose delivery to skin surface and influence of geometry using a radiometer, a spectral radiometer and an illuminance meter. The associated errors of the measurement methods were assessed. The spectral and spatial distribution of the radiant energy from the LED white light source was evaluated in order to define the maximum treatment area, setup and treatment protocol for wl-PDT. We compared the data with two red LED light sources we use for c-PDT. The calculated effective light dose is the product of the normalised absorption spectrum of the photosensitizer, protoporphyrin IX (PpIX), the irradiance spectrum and the treatment time. The effective light dose from daylight ranged from 3  ±  0.4 to 44  ±  6 J cm‑2due to varying weather conditions. The effective light dose for wl-PDT was reproducible for treatments but it varied across the treatment area between 4  ±  0.1 J cm‑2 at the edge and 9  ±  0.1 J cm‑2 centrally. The effective light dose for the red waveband (615–645 nm) was 0.42  ±  0.05 J cm‑2 on a clear day, 0.05  ±  0.01 J cm‑2 on an overcast day and 0.9  ±  0.01 J cm‑2 using the white light. This compares with 0.95  ±  0.01 and 0.84  ±  0.01 J cm‑2 for c-PDT devices. Estimated errors associated with indirect determination of daylight effective light dose were very significant, particularly for effective light doses less than 5 J cm‑2 (up to 83% for irradiance calculations). The primary source of error is in establishment of the relationship between irradiance or illuminance and effective dose. Use of the O’Mahoney model is

  19. Variation in pupil diameter in North American Gartersnakes (Thamnophis) is regulated by immersion in water, not by light intensity.

    Science.gov (United States)

    Fontenot, Clifford L

    2008-07-01

    A variable pupil generally regulates the amount of incoming light available for image formation on the retina. However, some of the semi-aquatic snakes (North American Gartersnakes, Thamnophis) that forage in relatively low light conditions reduce the pupil aperture in response to submergence underwater at the expense incoming light. Given that these snakes have all-cone retinas, reduction of incoming light because of pupillary constriction upon immersion seems counterintuitive. To test the effect of light and water on pupil aperture, three species of North American Gartersnakes (T. atratus, T. hammondii, and T. sirtalis) were exposed to nine light intensities in air and water. There was no effect of light on relative pupil aperture for any species. However, all three species showed a significant reduction in pupil aperture upon submergence underwater. The lack of a light response is surprising, and may be related to the method of accommodation in snakes. Snakes lack a ciliary muscle, and move the lens by constricting the pupil, which increases pressure in the posterior chamber and pushes the lens forward. Upon submergence, the snakes may be attempting to overcome the change in refractive index and defocus imposed by the water, by constricting the pupil. Thus, having the iris muscle involved in accommodation may preclude it from much of a light regulating function.

  20. Low-temperature crystallization of TiO{sub 2} nanotube arrays via hot water treatment and their photocatalytic properties under visible-light irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Krengvirat, Warapong [School of Materials and Mineral Resources Engineering, Engineering Campus, Universiti Sains Malaysia, Penang 14300 (Malaysia); Department of Electrical and Electronic Information Engineering, Toyohashi University of Technology, Aichi 441-8580 (Japan); Sreekantan, Srimala, E-mail: warapong001@hotmail.com [School of Materials and Mineral Resources Engineering, Engineering Campus, Universiti Sains Malaysia, Penang 14300 (Malaysia); Mohd Noor, Ahmad-Fauzi [School of Materials and Mineral Resources Engineering, Engineering Campus, Universiti Sains Malaysia, Penang 14300 (Malaysia); Negishi, Nobuaki [Institute for Environmental Management Technology, National Institute of Advanced, Industrial Science and Technology, Tsukuba, Ibaraki 305-8569 (Japan); Kawamura, Go; Muto, Hiroyuki [Department of Electrical and Electronic Information Engineering, Toyohashi University of Technology, Aichi 441-8580 (Japan); Matsuda, Atsunori, E-mail: matsuda@ee.tut.ac.jp [Department of Electrical and Electronic Information Engineering, Toyohashi University of Technology, Aichi 441-8580 (Japan)

    2013-01-15

    This work demonstrates the facile method to crystallize TiO{sub 2} nanotube arrays by simple immersion of amorphous TiO{sub 2} nanotube arrays into hot water at {approx}70-90 Degree-Sign C under ambient pressure and neutral pH. Hot water treatment induced the transformation of smooth nanotubes walls to granular anatase TiO{sub 2} nanoparticles. Higher treatment temperature and longer exposure time promoted the growth of anatase TiO{sub 2} nanocrystallites, and also lowered number of oxygen vacancies (V{sub O}{sup Bullet Bullet }). Furthermore, it allowed the adsorption of hydroxyl (OH) species and H{sub 2}O as well as the generation of the surface state, ca., Ti{sup 3+}. The presence of interstitial carbon species and surface states enabled the visible-light absorption. The adsorbed OH species and H{sub 2}O stimulated the photocatalytic oxidation by instantaneous reaction at the surface of nanotubes. Anatase TiO{sub 2} nanocrystallites formed by hot water treatment at 90 Degree-Sign C for 3 h exhibited efficient photocatalytic removal of dyes under visible-light irradiation with the decomposition rate of {approx}11% h{sup -1}, which is relatively higher than that of heat-treated arrays ({approx}9% h{sup -1}). The results indicate the potential of hot water treatment for the formation of anatase TiO{sub 2} nanocrystallites with efficient photocatalytic properties. -- Highlights: Black-Right-Pointing-Pointer Visible-light responsive TiO{sub 2} nanotubes were crystallized by immersion into hot water. Black-Right-Pointing-Pointer Temperature and exposure time determined the crystal growth and surface defect. Black-Right-Pointing-Pointer The presence of surface-active site contributed to a higher photocatalytic activity. Black-Right-Pointing-Pointer The product exhibited remarkable photo-degradation under visible-light irradiation.