WorldWideScience

Sample records for water chemistry surveillance

  1. Surface-water surveillance

    Energy Technology Data Exchange (ETDEWEB)

    Saldi, K.A.; Dirkes, R.L.; Blanton, M.L.

    1995-06-01

    This section of the 1994 Hanford Site Environmental Report summarizes the Surface water on and near the Hanford Site is monitored to determine the potential effects of Hanford operations. Surface water at Hanford includes the Columbia River, riverbank springs, ponds located on the Hanford Site, and offsite water systems directly east and across the Columbia River from the Hanford Site, and offsite water systems directly east and across the Columbia River from the Hanford Site. Columbia River sediments are also included in this discussion. Tables 5.3.1 and 5.3.2 summarize the sampling locations, sample types, sampling frequencies, and sample analyses included in surface-water surveillance activities during 1994. Sample locations are also identified in Figure 5.3.1. This section describes the surveillance effort and summarizes the results for these aquatic environments. Detailed analytical results are reported by Bisping (1995).

  2. Colour chemistry in water

    OpenAIRE

    Cardona, Maria

    2015-01-01

    Atmospheric carbon dioxide (CO2) levels have increased dramatically in the last few decades. Famous for causing global warming, CO2 is also resulting in the acidification of seas and oceans. http://www.um.edu.mt/think/colour-chemistry-in-water/

  3. Fog water chemistry in Shanghai

    Science.gov (United States)

    Li, Pengfei; Li, Xiang; Yang, Chenyu; Wang, Xinjun; Chen, Jianmin; Collett, Jeffrey L., Jr.

    2011-08-01

    With the aim of understanding the fog chemistry in a Chinese megacity, twenty-six fog water samples were collected in urban Shanghai from March 2009 to March 2010. The following parameters were measured: pH, electrical conductivity (EC), ten inorganic major ions ( SO42-, NO3-, NO2-, F -, Cl -, Na +, K +, Ca 2+, Mg 2+, NH4+) and four major organic acids (CH 3COO -, HCOO -, CO42-, MSA). The total ionic concentration (TIC) and EC of fog samples were one or two orders of magnitude higher than those often found in Europe, North America and other Asian countries. Pollutants were expected to be mainly from local sources, including factories, motor vehicle emissions and civil construction. Non-local sources such as moderate- and long-range transport of sea salt also contributed to pollution levels in fog events as indicated by back trajectory analysis. The pH of the fog water collected during the monitoring period varied from 4.68 to 6.58; acidic fogs represented about 30.8% of the total fog events during this period. The fog water was characterized by high concentrations of SO42- (20.0% of measured TIC), NO3- (17.1%), NH4+ (28.3%) and Ca 2+ (14.4%). SO42- and NO3-, the main precursors of fog acidity, were related to burning fossil fuels and vehicle emissions, respectively. NH4+, originating from the scavenging of gaseous ammonia and particulate ammonium nitrate and ammonium sulfate, and Ca 2+, originating from the scavenging of coarse particles, acted as acid neutralizers and were the main cause for the relatively high pH of fogs in Shanghai. The ratio of ( SO42- + NO3-)/( NH4+ + Ca 2+) was lower than 1, indicating the alkaline nature of the fog water. A high ratio of NO3-/ SO42- and low ratio of HCOO -/CH 3COO - were consistent with large contributions from vehicular emissions that produce severe air pollution in megacities.

  4. Environmental and ground-water surveillance at Hanford

    Energy Technology Data Exchange (ETDEWEB)

    Dirkes, R.L.; Luttrell, S.P.

    1995-06-01

    Environmental and ground-water surveillance of the Hanford Site and surrounding region is conducted to demonstrate compliance with environmental regulations, confirm adherence to DOE environmental protection policies, support DOE environmental management decisions, and provide information to the public. Environmental surveillance encompasses sampling and analyzing for potential radiological and nonradiological chemical contaminants on and off the Hanford Site. Emphasis is placed on surveillance of exposure pathways and chemical constituents that pose the greatest risk to human health and the environment.

  5. The next Stages in Researching Water Fluoridation: Evaluation and Surveillance

    Science.gov (United States)

    Downer, Martin C.; Blinkhorn, Anthony S.

    2007-01-01

    Objective: (1) to provide a commentary on a conference held at the University of Manchester entitled Researching Water Fluoridation: Evaluation and Surveillance; (2) to synthesize from the proceedings of the meeting suggestions for future research and public health surveillance. Method: The main points and problematic issues raised by the speakers…

  6. National Status and Trends, Benthic Surveillance Project Chemistry Data, 1984-1992, National Centers for Coastal Ocean Science

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The National Status and Trends (NS&T) Benthic Surveillance Project Chemistry data file reports the trace concentrations of a suite of chemical contaminants in...

  7. National Status and Trends, Benthic Surveillance Project Chemistry Data, 1984-1992, National Centers for Coastal Ocean Science

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The National Status and Trends (NSandT) Benthic Surveillance Project Chemistry data file reports the trace concentrations of a suite of chemical contaminants in...

  8. Monitoring cycle water chemistry in fossil plants

    Energy Technology Data Exchange (ETDEWEB)

    Aschoff, A.F.; Sopocy, D.M.; Eglar, D.T. (Sargent and Lundy, Chicago, IL (United States)); Jonas, O. (Jonas, Inc., Wilmington, DE (United States)); Rice, J.K. (Rice (James K.), Chartered (United States)); Stauffer, C.C.; Allmon, W.E. (Babcock and Wilcox Co., Alliance, OH (United States))

    1991-10-01

    In June 1986, EPRI published the Interim Consensus Guidelines on Fossil Plant Cycle Chemistry.'' Previously published Volume 1 of the final report presents information obtained during a field monitoring program, using state-of-the-art monitoring and data acquisition systems, at four utility units representing different types of design, operation, metallurgy, and chemical treatment. A separate report, Volume 2, will be published giving the results of a parallel monitoring effort conducted by nine international organizations representing 29 generating units of various types. The present Volume 3 presents the conclusions and recommendations of the water chemistry monitoring project at four fossil-fired stations. The three volumes comprising this final report for this project will furnish the basis for subsequent modification and reissue of guidelines on fossil plant cycle chemistry. (VC)

  9. A preliminary analysis of water chemistry of the Mkuze Wetland ...

    African Journals Online (AJOL)

    drinie

    2002-01-01

    Jan 1, 2002 ... 2 School of Pure and Applied Chemistry, University of Natal, Durban 4041, South Africa. Abstract ... In order to investigate the water chemistry of this system, water samples were collected throughout the study area from surface water ...... ELLERY K (1989) The inorganic chemistry of peat from the Mauna-.

  10. Variability in chemistry of surface and soil waters of an ...

    African Journals Online (AJOL)

    Water chemistry is important for the maintenance of wetland structure and function. Interpreting ecological patterns in a wetland system therefore requires an in-depth understanding of the water chemistry of that system. We investigated the spatial distribution of chemical solutes both in soil pore water and surface water, ...

  11. Water chemistry practice at German BWR plants

    Energy Technology Data Exchange (ETDEWEB)

    Stellwag, B. [Framatome ANP GmbH, Erlangen (Germany); Staudt, U. [VGB PowerTech e.V., Essen (Germany)

    2005-02-01

    As visual examinations carried out in 1994 detected cracks in a German boiling water reactor (BWR) plant due to intergranular stress corrosion cracking in core shroud components manufactured from Nb-stabilized CrNi steel 1.4550, safety-related assessments and in-service inspections were subsequently performed for the other six German BWRs. No cracks were found in the core shrouds of these plants. The second major event in the early 1990s was the detection of cracks at various German BWRs in piping systems made of Ti-stabilized CrNi steel 1.4541 caused by thermal sensitization in the heat-affected zone of welds. Comprehensive investigations resulted in a number of remedial measures (repair, replacement) implemented at piping in contact with reactor coolant of temperatures above 200 C. Thanks to the remedial measures and according to the analyses performed, cracking in the components in question due to the considered damage mechanisms need not be expected. German operators have therefore continued operating their BWR plants on normal water chemistry with an oxidizing environment. As a precaution, more stringent reactor coolant quality requirements have been specified and the limiting values of VGB Guideline R 401 J revised. This paper gives an overview of the trends in chemistry parameters at German BWR plants in the past 10 years. In addition, other relevant experience gained from the German BWR plants operating under normal water chemistry conditions is outlined: dose rates and collective doses, fuel performance, and results of periodic in-service inspections of major components of the reactor system. In the nearly 10 years of plant operation since implementation of the remedial measures, no cracks or other indications have been detected in any of the systems and components concerned. (orig.)

  12. Characterisation of the inorganic chemistry of surface waters in ...

    African Journals Online (AJOL)

    The main purpose of this study was to determine a simple inorganic chemistry index that can be used for all surface waters in South Africa, in order to characterise the inorganic chemistry of surface waters. Water quality data collected up until 1999 from all sample monitoring stations (2 068 monitoring stations, 364 659 ...

  13. Montane wetland water chemistry, Uinta Mountains, Utah

    Science.gov (United States)

    Severson, K. S.; Matyjasik, M.; Ford, R. L.; Hernandez, M. W.; Welsh, S. B.; Summers, S.; Bartholomew, L. M.

    2009-12-01

    This study attempts to determine the relationship between surface and groundwater chemistry and wetland characteristics within the Reader Lakes watershed, Uinta Mountains. The dominant rock type in the study area is quartz sandstone of the Hades Pass formation, Unita Mountain Group (Middle Proterozoic). Minor amounts of interbedded arkose and illite-bearing shale are also present. Water chemistry data have been collected from more than one hundred locations during the 2008 and 2009 summer seasons. The Reader Creek watershed is approximately 9.8 km long and about 3.5 km wide in the central portion of the basin. Direct precipitation is the primary source of groundwater recharge and the area is typically covered by snow from November until May. Four distinct wetland complexes, designated as the upper, middle, lower and the sloping fen, constitute the major wetland environments in the study area. The chemistry of the melt water from the high-elevation snowfield is affected by weathering of incorporated atmospheric dust and surface rocks. Total dissolved solids in both years were between 7 and 9 mg/L. Major anions include HCO3 (averaging 4.0 mg/L), SO4 (1.3 mg/L), NO3 (0.9 mg/L), Cl (0.8 mg/L), F (0.07 mg/L), PO4 (0.03 mg/L), and Br(0.015 mg/L). Major cations include Na (1.1 mg/L), Ca (1.0 mg/L), K (0.28 mg/L), and Mg (0.15 mg/L). Groundwater concentrations in the lower meadow, as measured in piezomters, are distinctly different, with the following maximum concentrations of anions: HCO3 (36.7 mg/L), SO4 (5.0 mg/L), Cl (3.4 mg/L), NO3 (0.9 mg/L), PO4 (0.28 mg/L), F (0.23 mg/L), Br (0.12 mg/L), and cations: Ca (22 mg/L), Na (4.6 mg/L), Mg (3.4 mg/L), and K (1.8 mg/L)- with a maximum value of 83 mg/L for total dissolved solids. Waters in Reader Creek, the main trunk channel, are typically sodium-potassium and sodium -potassium bicarbonate, with some calcium-bicarbonate, mostly in the middle part of the watershed. Groundwater from springs is sodium-potassium in the upper

  14. Monitoring cycle water chemistry in fossil plants

    Energy Technology Data Exchange (ETDEWEB)

    Aschoff, A.F.; Sopocy, D.M.; Eglar, D.T. (Sargent and Lundy, Chicago, IL (United States)); Jonas, O. (Jonas, Inc., Wilmington, DE (United States)); Rice, J.K. (Rice (James K.), Chartered (United States)); Stauffer, C.C.; Allmon, W.E. (Babcock and Wilcox Co., Alliance, OH (United States))

    1991-10-01

    EPRI report CS-4629, published in 1986, contains operating cycle chemistry guidelines to assist utilities in reducing water and steam contamination and resulting corrosion, scaling, and deposition. These guidelines were based on consensus opinion utilizing information then available and were not validated through actual plant testing. The objectives of this project are: to monitor the major parameters of cycle chemistry in a range of fossil-fired plants; to compare the monitored parameters with the interim guidelines. The project team designed and constructed state-of-the-art instrumentation and data acquisition systems to measure and record continuously the chemical parameters specified in the interim consensus guidelines (ICG). The team then installed and operated these systems at four utility power plants. Nine international organizations conducted parallel monitoring efforts on 29 generating units. An industrial fossil plant group of 14 utilities and boiler and turbine manufacturers reviewed the monitoring results from each of the plants as did the participating international organizations. 137 figs., 43 tabs.

  15. Surveillance

    DEFF Research Database (Denmark)

    Albrechtslund, Anders; Coeckelbergh, Mark; Matzner, Tobias

    Studying surveillance involves raising questions about the very nature of concepts such as information, technology, identity, space and power. Besides the maybe all too obvious ethical issues often discussed with regard to surveillance, there are several other angles and approaches that we should...... like to encourage. Therefore, our panel will focus on the philosophical, yet non-ethical issues of surveillance in order to stimulate an intense debate with the audience on the ethical implications of our enquiries. We also hope to provide a broader and deeper understanding of surveillance....

  16. Characterisation of the inorganic chemistry of surface waters in ...

    African Journals Online (AJOL)

    2010-08-16

    Aug 16, 2010 ... Using an inorganic chemistry index (ICI) a more detailed analysis can be performed. The ICI shows that the surface water chemistry in South Africa is dominated by chemical weathering, chloride salinisa- tion and sulphate contamination. Based on the importance of these factors, primary catchment areas in ...

  17. Organic chemistry - Fast reactions 'on water'

    NARCIS (Netherlands)

    Klijn, JE; Engberts, JBFN

    2005-01-01

    Efficient reactions in aqueous organic chemistry do not require soluble reactants, as had been thought. A newly developed ‘on-water’ protocol is characterized by short reaction times, and the products are easy to isolate.

  18. BWR water chemistry guidelines and PWR primary water chemistry guidelines in Japan – Purpose and technical background

    Energy Technology Data Exchange (ETDEWEB)

    Kawamura, Hirotaka, E-mail: kawamuh@criepi.denken.or.jp [Central Research Institute of Electric Power Industry (Japan); Hirano, Hideo [Central Research Institute of Electric Power Industry (Japan); Katsumura, Yousuke [University of Tokyo (Japan); Uchida, Shunsuke [Tohoku University (Japan); Mizuno, Takayuki [Mie University (Japan); Kitajima, Hideaki; Tsuzuki, Yasuo [Japan Nuclear Safety Institute (Japan); Terachi, Takumi [Institute of Nuclear Safety System, Inc. (Japan); Nagase, Makoto; Usui, Naoshi [Hitachi-GE Nuclear Energy, Ltd. (Japan); Takagi, Junichi; Urata, Hidehiro [Toshiba Corporation (Japan); Shoda, Yasuhiko; Nishimura, Takao [Mitsubishi Heavy Industry, Ltd. (Japan)

    2016-12-01

    Highlights: • Framework of BWR/PWR water chemistry Guidelines in Japan are presented. • Guideline necessity, definitions, philosophy and technical background are mentioned. • Some guideline settings for control parameters and recommendations are explaines. • Chemistry strategy is also mentioned. - Abstract: After 40 years of light water reactor (LWR) operations in Japan, the sustainable development of water chemistry technologies has aimed to ensure the highest coolant system component integrity and fuel reliability performance for maintaining LWRs in the world; additionally, it aimed to achieve an excellent dose rate reduction. Although reasonable control and diagnostic parameters are utilized by each boiling water reactor (BWR) and pressurized water reactor (PWR) owner, it is recognized that specific values are not shared among everyone involved. To ensure the reliability of BWR and PWR operation and maintenance, relevant members of the Atomic Energy Society of Japan (AESJ) decided to establish guidelines for water chemistry. The Japanese BWR and PWR water chemistry guidelines provide strategies to improve material and fuel reliability performance as well as to reduce dosing rates. The guidelines also provide reasonable “control values”, “diagnostic values” and “action levels” for multiple parameters, and they stipulate responses when these levels are exceeded. Specifically, “conditioning parameters” are adopted in the Japanese PWR primary water chemistry guidelines. Good practices for operational conditions are also discussed with reference to long-term experience. This paper presents the purpose, technical background and framework of the preliminary water chemistry guidelines for Japanese BWRs and PWRs. It is expected that the guidelines will be helpful as an introduction to achieve safety and reliability during operations.

  19. Experience of water chemistry in HWR

    OpenAIRE

    桜井 直行; 北端 琢也

    1983-01-01

    Experience of the heavy water and primary coolantchemistry of the Fugen is described. Deterioration has beenobserved in the weak basic ion exchange resins used in theheavy water purification system. Extensive studies to pro-long the life of resins are now going on. Amount of iron inthe feed water has been reduced by means of oxygen injection,operational improvement of condensate demineralizers,hotdrain-off of the feed water circuit,and sufficient flushingprior to operations.

  20. Contribution of water chemistry and fish condition to otolith chemistry: comparisons across salinity environments.

    Science.gov (United States)

    Izzo, C; Doubleday, Z A; Schultz, A G; Woodcock, S H; Gillanders, B M

    2015-06-01

    This study quantified the per cent contribution of water chemistry to otolith chemistry using enriched stable isotopes of strontium ((86) Sr) and barium ((137) Ba). Euryhaline barramundi Lates calcarifer, were reared in marine (salinity 40), estuarine (salinity 20) and freshwater (salinity 0) under different temperature treatments. To calculate the contribution of water to Sr and Ba in otoliths, enriched isotopes in the tank water and otoliths were quantified and fitted to isotope mixing models. Fulton's K and RNA:DNA were also measured to explore the influence of fish condition on sources of element uptake. Water was the predominant source of otolith Sr (between 65 and 99%) and Ba (between 64 and 89%) in all treatments, but contributions varied with temperature (for Ba), or interactively with temperature and salinity (for Sr). Fish condition indices were affected independently by the experimental rearing conditions, as RNA:DNA differed significantly among salinity treatments and Fulton's K was significantly different between temperature treatments. Regression analyses did not detect relations between fish condition and per cent contribution values. General linear models indicated that contributions from water chemistry to otolith chemistry were primarily influenced by temperature and secondly by fish condition, with a relatively minor influence of salinity. These results further the understanding of factors that affect otolith element uptake, highlighting the necessity to consider the influence of environment and fish condition when interpreting otolith element data to reconstruct the environmental histories of fish. © 2015 The Fisheries Society of the British Isles.

  1. Clean Air Markets - Monitoring Surface Water Chemistry

    Science.gov (United States)

    Learn about how EPA uses Long Term Monitoring (LTM) and Temporily Integrated Monitoring of Ecosystems (TIME) to track the effect of the Clean Air Act Amendments on acidity of surface waters in the eastern U.S.

  2. Water chemistry of Rocky Mountain Front Range aquatic ecosystems

    Science.gov (United States)

    Robert C. Musselman; Laura Hudnell; Mark W. Williams; Richard A. Sommerfeld

    1996-01-01

    A study of the water chemistry of Colorado Rocky Mountain Front Range alpine/subalpine lakes and streams in wilderness ecosystems was conducted during the summer of 1995 by the USDA Forest Service Arapaho and Roosevelt National Forests and Rocky Mountain Forest and Range Experiment Station, and the University of Colorado Institute of Alpine and Arctic Research. Data...

  3. Social representations of drinking water: subsidies for water quality surveillance programmes.

    Science.gov (United States)

    Carmo, Rose Ferraz; Bevilacqua, Paula Dias; Barletto, Marisa

    2015-09-01

    A qualitative study was developed aimed at understanding the social representations of water consumption by a segment of the population of a small town in Brazil. A total of 19 semi-structured interviews were carried out and subjected to a content analysis addressing opinion on drinking water, characteristics of drinking water and its correlation to health and diseases, criteria for water usage and knowledge on the source and accountability for drinking-water quality. Social representations of drinking water predominantly incorporate the municipal water supply and sanitation provider and its quality. The identification of the municipal water supply provider as alone responsible for maintaining water quality indicated the lack of awareness of any health surveillance programme. For respondents, chlorine was accountable for conferring colour, odour and taste to the water. These physical parameters were reported as the cause for rejecting the water supplied and suggest the need to review the focus of health-educational strategies based on notions of hygiene and water-borne diseases. The study allowed the identification of elements that could contribute to positioning the consumers vs. services relationship on a level playing field, enabling dialogue and exchange of knowledge for the benefit of public health.

  4. The Role of Water Chemistry in Marine Aquarium Design: A Model System for a General Chemistry Class

    Science.gov (United States)

    Keaffaber, Jeffrey J.; Palma, Ramiro; Williams, Kathryn R.

    2008-01-01

    Water chemistry is central to aquarium design, and it provides many potential applications for discussion in undergraduate chemistry and engineering courses. Marine aquaria and their life support systems feature many chemical processes. A life support system consists of the entire recirculation system, as well as the habitat tank and all ancillary…

  5. Chemistry of trace elements in coalbed methane product water.

    Science.gov (United States)

    McBeth, Ian; Reddy, Katta J; Skinner, Quentin D

    2003-02-01

    Extraction of methane (natural gas) from coal deposits is facilitated by pumping of aquifer water. Coalbed methane (CBM) product water, produced from pumping ground water, is discharged into associated unlined holding ponds. The objective of this study was to examine the chemistry of trace elements in CBM product water at discharge points and in associated holding ponds across the Powder River Basin, Wyoming. Product water samples from discharge points and associated holding ponds were collected from the Cheyenne River (CHR), Belle Fourche River (BFR), and Little Powder River (LPR) watersheds during the summers of 1999 and 2000. Samples were analyzed for pH, Al (aluminum), As (arsenic), B (boron), Ba (barium), Cr (chromium), Cu (copper), F (fluoride), Fe (iron), Mn (manganese), Mo (molybdenum), Se (selenium), and Zn (zinc). Chemistry of trace element concentrations were modeled with the MINTEQA2 geochemical equilibrium model. Results of this study show that pH of product water for three watersheds increased in holding ponds. For example the pH of CBM product water increased from 7.21 to 8.26 for LPR watershed. Among three watersheds, the CBM product water exhibited relatively less change in trace element concentrations in CHR watershed holding ponds. Concentration of dissolved Al, Fe, As, Se, and F in product water increased in BFR watershed holding ponds. For example, concentration of dissolved Fe increased from 113 to 135 microg/L. Boron, Cu, and Zn concentrations of product water did not change in BFR watershed holding ponds. However, concentration of dissolved Ba, Mn, and Cr in product water decreased in BFR watershed holding ponds. For instance, Ba and Cr concentrations decreased from 445 to 386 microg/L and from 43.6 to 25.1 microg/L, respectively. In the LPR watershed, Al, Fe, As, Se, and F concentrations of product water increased substantially in holding ponds. For example, Fe concentration increased from 192 to 312 microg/L. However, concentration of

  6. Flow Accelerated Corrosion: Effect of Water Chemistry and Database Construction

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Eun Hee; Kim, Kyung Mo; Lee, Gyeong Geun; Kim, Dong Jin [KAERI, Daejeon (Korea, Republic of)

    2016-05-15

    Flow accelerated corrosion (FAC) of carbon steel piping in pressurized water reactors (PWRs) has been a major issue in nuclear industry. Severe accidents at Surry Unit 2 in 1986 and Mihama Unit 3 in 2004 initiated the world wide interest in this area. FAC is a dissolution process of the protective oxide layer on carbon steel or low-alloy steel when these parts are exposed to flowing water (single-phase) or wet steam (two-phase). In a single-phase flow, a scalloped, wavy, or orange peel and in a two-phase flow, tiger striping is observed, respectively. FAC is affected by many parameters, like material composition, pH, dissolved oxygen (DO), flow velocity, system pressure, and steam quality. This paper describes the water chemistry factors influencing on FAC and the database is then constructed using literature data. In order to minimize FAC in NPPs, the optimal method is to control water chemistry parameters. However, quantitative data about FAC have not been published for proprietary reason even though qualitative behaviors of FAC have been well understood. A database was constructed using experimental data in literature. Accurate statistical analysis will be performed using this database to identify the relationship between the FAC rate and test environment.

  7. Water chemistry management of research reactor in JAERI

    Energy Technology Data Exchange (ETDEWEB)

    Yoshijima, Tetsuo [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1998-10-01

    The JRR-3M cooling system consists of four systems, namely; (1) primary cooling system, (2) heavy water cooling system, (3) helium system and (4) secondary cooling system. The heavy water is used for reflector and pressurized with helium gas. Water chemistry management of the JRR-3M cooling systems is one of the important subject for the safety operation. The main objects are to prevent the corrosion of cooling system and fuel elements, to suppress the plant radiation build-up and to minimize the generation of radioactive waste. All measured values were within the limits of specifications and JRR-3M reactor was operated with safety in 1996. Spent fuels of JRR-3M reactor are stored in the spent fuel pool. This pool water has been analyzed to prevent corrosion of aluminum cladding of spent fuels. Water chemistry of spent fuel pool water is applied to the prevention of corrosion of aluminum alloys including fuel cladding. The JRR-2 reactor was eternally stopped in December 1996 and is now under decommissioning. The JRR-2 reactor is composed of heavy water tank, fuel guide tube and horizontal experimental hole. These are constructed of aluminum alloy and biological shield and upper shield are constructed of concrete. Three types of corrosion of aluminum alloy were observed in the JRR-2. The Alkaline corrosion of aluminum tube occurred in 1972 because of the mechanical damage of the aluminum fuel guide tube which is used for fuel handling. Modification of the reactor top shield was started in 1974 and completed in 1975. (author)

  8. Optimum Water Chemistry in radiation field buildup control

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Chien, C. [Vallecitos Nuclear Center, Pleasanton, CA (United States)

    1995-03-01

    Nuclear utilities continue to face the challenGE of reducing exposure of plant maintenance personnel. GE Nuclear Energy has developed the concept of Optimum Water Chemistry (OWC) to reduce the radiation field buildup and minimize the radioactive waste production. It is believed that reduction of radioactive sources and improvement of the water chemistry quality should significantly reduce both the radiation exposure and radwaste production. The most important source of radioactivity is cobalt and replacement of cobalt containing alloy in the core region as well as in the entire primary system is considered the first priority to achieve the goal of low exposure and minimized waste production. A plant specific computerized cobalt transport model has been developed to evaluate various options in a BWR system under specific conditions. Reduction of iron input and maintaining low ionic impurities in the coolant have been identified as two major tasks for operators. Addition of depleted zinc is a proven technique to reduce Co-60 in reactor water and on out-of-core piping surfaces. The effect of HWC on Co-60 transport in the primary system will also be discussed.

  9. Influence of surface structure and chemistry on water droplet splashing.

    Science.gov (United States)

    Koch, Kerstin; Grichnik, Roland

    2016-08-06

    Water droplet splashing and aerosolization play a role in human hygiene and health systems as well as in crop culturing. Prevention or reduction of splashing can prevent transmission of diseases between animals and plants and keep technical systems such as pipe or bottling systems free of contamination. This study demonstrates to what extent the surface chemistry and structures influence the water droplet splashing behaviour. Smooth surfaces and structured replicas of Calathea zebrina (Sims) Lindl. leaves were produced. Modification of their wettability was done by coating with hydrophobizing and hydrophilizing agents. Their wetting was characterized by contact angle measurement and splashing behaviour was observed with a high-speed video camera. Hydrophobic and superhydrophilic surfaces generally showed fewer tendencies to splash than hydrophobic ones. Structuring amplified the underlying behaviour of the surface chemistries, increasing hydrophobic surfaces' tendency to splash and decreasing splash on hydrophilic surfaces by quickly transporting water off the impact point by capillary forces. The non-porous surface structures found in C. zebrina could easily be applied to technical products such as plastic foils or mats and coated with hydrophilizing agents to suppress splash in areas of increased hygiene requirements or wherever pooling of liquids is not desirable.This article is part of the themed issue 'Bioinspired hierarchically structured surfaces for green science'. © 2016 The Author(s).

  10. Simulation of Water Chemistry using and Geochemistry Code, PHREEQE

    Energy Technology Data Exchange (ETDEWEB)

    Chi, J.H. [Korea Electric Power Research Institute, Taejeon (Korea)

    2001-07-01

    This report introduces principles and procedures of simulation for water chemistry using a geochemistry code, PHREEQE. As and example of the application of this code, we described the simulation procedure for titration of an aquatic sample with strong acid to investigate the state of Carbonates in aquatic solution. Major contents of this report are as follows; Concepts and principles of PHREEQE, Kinds of chemical reactions which may be properly simulated by PHREEQE, The definition and meaning of each input data, An example of simulation using PHREEQE. (author). 2 figs., 1 tab.

  11. Drinking Water Quality Surveillance in a Vulnerable Urban Ward of Ahmedabad.

    Science.gov (United States)

    Iyer, Veena; Choudhury, Nandini; Azhar, Gulrez Shah; Somvanshi, Bhushan

    2014-05-01

    The World Bank estimates that 21% of all communicable diseases in India are related to unsafe water with diarrhoea alone causing more than 0.1 million deaths annually. The WHO drinking water surveillance parameters of quality, quantity, accessibility, affordability and continuity were assessed in one vulnerable ward of Ahmedabad-a fast growing city in Western India. Interviews with key informants of the ward office, health centre and water supply department, secondary analysis and mapping of field test reports and a questionnaire-based survey of different household types were conducted. We found that Ahmedabad Municipal Corporation (AMC) supplies water to the ward intermittently for two hours during the day. Housing society clusters supplement their AMC water supply with untested bore-well water. The water quality surveillance system is designed for a twenty-four-hour piped distribution of treated surface water. However, in order to maintain surveillance over an intermittent supply that includes ground water, the sampling process should include periodic surveys of water actually consumed by the citizens. The laboratory capacity of the Central Water Testing Laboratory should expand to include more refined tests for microbial and chemical contamination.

  12. Influence of mine hydrogeology on mine water discharge chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Rees, S.B.; Bowell, R.J.; Wiseman, I. [SRK Consulting, Cardiff (United Kingdom)

    2002-10-01

    Using data for 18 coal mine discharges in the UK, the influence of discharge hydrogeology on discharge chemistry is assessed and typical chemical parameters derived for five discharge types. A combination of modified and new classification schemes is used to differentiate between the various discharge sources. Drainage from spoil tips generally has a pH below 5 and net-alkalinity values as low as -2500 mgl{sup -1} CaCO{sub 3}. Drainage from flooded workings and pumped discharges are net-alkaline, while drainage from flooded and free draining workings are either moderately net-alkaline or net-acidic. Iron is the major contaminant of concern, although many mine waters contain less than 30 mgl{sup -1} and Fe/SO{sub 4} ratios are less than unity. The classification schemes developed can be used to assess mine water treatment requirements and processes operating in passive treatment systems. 11 refs., 7 figs., 2 tabs.

  13. Water chemistries at thermal and nuclear power stations: A new level of information support

    Science.gov (United States)

    Ochkov, V. F.

    2011-07-01

    Methods used by the Moscow Power Engineering Institute's Department for Technologies of Water and Fuel in providing information support to the chemical departments of power stations in the field of organizing water chemistry of power units are described. Information is given on a new handbook on water chemistries at thermal and nuclear power stations and on the site supplementing this handbook.

  14. Surveillance of potential pathogenic fungi associated with water ...

    African Journals Online (AJOL)

    The entire Kainji Lake and the riverine areas upstream of Yauri were surveyed monthly between February and May 2002 with a motorboat to make full inspection of fungi-infested water hyacinth plants. Various parts of water hyacinth plant showing symptoms of fungal infection were collected, dried between paper towels, ...

  15. Readying Community Water Fluoridation Advocates through Training, Surveillance, and Empowerment.

    Science.gov (United States)

    Veschusio, C; Jones, M K; Mercer, J; Martin, A B

    2017-11-10

    This paper describes the Community Water Fluoridation Advocacy Training Project that was designed to develop networks of community water fluoridation advocates in rural communities. The South Carolina (SC) Department of Health and Environmental Control Division of Oral Health staff and the SC Dental Association were responsible for developing and facilitating the training sessions for key policy influencers, which included medical and dental providers, early childhood educators, and water system operators and managers. Findings from the post-training survey indicate that participants increased their knowledge and skills to discuss the impact of water fluoridation on the dental health of community residents. Participants identified a need for online access to water fluoridation education and advocacy materials. Dental public health competencies illustrated: communication and collaboration with groups and individuals, and advocate, implement and evaluate public health policy, legislation and regulations. Copyright© 2017 Dennis Barber Ltd.

  16. Single Picture Integration for Territorial Water Surveillance (SPITS): An initiative to improve situational awareness in littoral waters

    NARCIS (Netherlands)

    Theil, A.; Huizing, A.; Heijningen, A.W.P.

    2006-01-01

    Single Picture Integration for Territorial Water Surveillance (SPITS) is an initiative conducted by TNO Defence, Security and Safety in which techniques to enhance the quality of the maritime surface picture are considered. Observing the environment with a suite of dissimilar sensors is considered

  17. Development Of A Surveillance System For Potability Of Water In Rural Areas

    Directory of Open Access Journals (Sweden)

    Gandotra V.K

    1998-01-01

    Full Text Available Research question: Whether establishment of a water surveillance system in rural areas and concomitant action in event of detection of contamination will have an impact on diarrhoea related morbidity and mortality. Hypothesis: 1. It is possible to establish water testing laboratories in selected schools in rural areas. 2. If water samples are found contaminated, immediate corrective action will result in reduction of diarrhoea related morbidity and mortality. Objectives: 1. To study the feasibility of establishing water testing facility in the science laboratories of schools. 2. To study the impact of preventive measures in the community if immediate steps for household purification of water and treatment of diarrhoea cases are taken. Study design: Interventional study. Setting: A rural block. Participants: Science teachers of high schools and field workers. Interventions: 1. Training of schoolteachers for water testing and field workers for collection of water samples and diarrhoea control measures. 2. Establishing of water testing laboratories in schools. 3. In case of detection of water contamination, corrective action at different levels. 4. Propagation of ORS for management of diarrhoeas. Statistical analysis: Percentages, Paired ‘t’ test, Chi square test. Results: Reduction in diarrhoea related morbidity and mortality was observed. Conclusions: It is feasible to develop a water surveillance system in rural areas utilizing local resources. If combined with educational measures, it will significantly reduce diarrhoea related morbidity and mortality.

  18. History of the water chemistry for the few tube test model

    Energy Technology Data Exchange (ETDEWEB)

    Moss, S.A.; Simpson, J.L.

    1979-09-01

    The water chemistry activities carried out in support of the Few Tube Test are described. This test was conducted to provide design confirmation data for the Clinch River Breeder Reactor Project (CRBRP) steam generators. Proposed CRBRP chemistry was followed; all volatile treatment (AVT) of water was carried out with on-line monitoring capability.

  19. [Local contexts of drinking-water quality surveillance: Brazil and Colombia].

    Science.gov (United States)

    Guzmán-Barragán, Blanca L; Días Bevilacqua, Paula; Nava-Tovar, Gerardo

    2015-12-01

    Objective This article aims to analyze comparatively the national surveillance systems of water quality for human consumption (DWQS) of Brazil and Colombia, seeking to understand how practices are organized in these countries, along with their limits and possibilities. Methods The National Cross Comparison methodology was used with document analysis of secondary sources, with the purpose of discussing the similarities and differences between the two systems using the WHO’s Guidelines for Drinking Water Quality. Results The legal framework on DWQS in Brazil and Colombia was defined in the 70s and 80s, coinciding with the international visibility of this issue. Thereafter, DWQS practices in Brazil have been defined and organized in a national program, which has only recently started in Colombia. The current Brazilian and Colombian legislations show progress in technical elements that guide surveillance practices, such as the incorporation of risk assessment methodologies. The Colombian legislation defines the regulation of water supply services provision, which is not contemplated in Brazilian legislation. Elements such as decentralization, intersectionality, universality and right to information are included in the legislations of both countries, although further action on DWQS is needed. Conclusions Brazil and Colombia have similarities in the implementation of DWQS, despite being at different points in the implementation timeline. Actions on drinking-water quality surveillance are necessary to guarantee human rights related to the protection of the environment, such as universal access to drinking water, contributing to the promotion of health.

  20. Applicability of oxygenated water chemistry for PWR secondary systems

    Energy Technology Data Exchange (ETDEWEB)

    Hermansson, H.P. [Studsvik Nuclear AB, Nykoeping (Sweden); Takiguchi, H.; Otoha, K. [Japan Atomic Power Co., Tokyo (Japan)

    2002-07-01

    Introduction of oxygenated water chemistry (OWC) in PWR secondary side is considered as a means to reduce the transportation of corrosion products into the steam generator and thus also minimizing crevice deposits and subsequent materials problems. One main concern, however, is the risk of inter-granular attack (IGA) in crevices. In order to study effects on crevice tube IGA by OWC, a series of experiments were performed in a steam generator (SG) simulating loop. This comprised a SG tube and a tube support plate (TSP) together forming the crevice. The over-all objective of the work accounted here was to demonstrate that it is possible to operate the steam generator secondary side with OWC without causing intolerable IGA or other types of attack on the tube in the crevice area. Tubes of sensitized Alloy 600 were exposed during a total of nine experiments in an autoclave using a TSP/tube arrangement with an asymmetric crevice design. Experiments were performed at high and low pH and potential under open and packed crevice conditions. The aggressiveness of the crevice environment was also further increased by addition of carbonate and chloride. Furthermore the tube was pressurized. Experimental parameters were monitored on the primary side as well as in the secondary bulk phase and in the crevice. (authors)

  1. Chemistry?!

    Indian Academy of Sciences (India)

    Chemistry is the science of matter and of its transformations, and life is its highest expression. It provides structures endowed with properties and develops processes for the synthesis of structures. It plays a primordial role in our understanding of material phe- nomena, in our capability to act upon them, to modify them, to.

  2. The Systemic Approach to Teaching and Learning: Water Chemistry ...

    African Journals Online (AJOL)

    The systemic approach to teaching and learning (SATL) has been developed during the last decade 1-7). SATL techniques have been implemented and evaluated in many different disciplines (chemistry, biology, physics, and math) in all educational levels, but the major SATL applications have been reported on chemistry ...

  3. Linking soil- and stream-water chemistry based on a Riparian Flow-Concentration Integration Model

    Directory of Open Access Journals (Sweden)

    J. Seibert

    2009-12-01

    Full Text Available The riparian zone, the last few metres of soil through which water flows before entering a gaining stream, has been identified as a first order control on key aspects of stream water chemistry dynamics. We propose that the distribution of lateral flow of water across the vertical profile of soil water chemistry in the riparian zone provides a conceptual explanation of how this control functions in catchments where matrix flow predominates. This paper presents a mathematical implementation of this concept as well as the model assumptions. We also present an analytical solution, which provides a physical basis for the commonly used power-law flow-load equation. This approach quantifies the concept of riparian control on stream-water chemistry providing a basis for testing the concept of riparian control. By backward calculation of soil-water-chemistry profiles, and comparing those with observed profiles we demonstrate that the simple juxtaposition of the vertical profiles of water flux and soil water chemistry provides a plausible explanation for observed variations in stream water chemistry of several major stream components such as Total Organic Carbon (TOC, magnesium, calcium and chloride. The "static" implementation of the model structure presented here provides a basis for further development to account for seasonal influences and hydrological hysteresis in the representation of hyporheic, riparian, and hillslope processes.

  4. Surveillance for waterborne disease outbreaks associated with drinking water---United States, 2007--2008.

    Science.gov (United States)

    Brunkard, Joan M; Ailes, Elizabeth; Roberts, Virginia A; Hill, Vincent; Hilborn, Elizabeth D; Craun, Gunther F; Rajasingham, Anu; Kahler, Amy; Garrison, Laurel; Hicks, Lauri; Carpenter, Joe; Wade, Timothy J; Beach, Michael J; Yoder Msw, Jonathan S

    2011-09-23

    Since 1971, CDC, the Environmental Protection Agency (EPA), and the Council of State and Territorial Epidemiologists have collaborated on the Waterborne Disease and Outbreak Surveillance System (WBDOSS) for collecting and reporting data related to occurrences and causes of waterborne disease outbreaks associated with drinking water. This surveillance system is the primary source of data concerning the scope and health effects of waterborne disease outbreaks in the United States. Data presented summarize 48 outbreaks that occurred during January 2007--December 2008 and 70 previously unreported outbreaks. WBDOSS includes data on outbreaks associated with drinking water, recreational water, water not intended for drinking (WNID) (excluding recreational water), and water use of unknown intent (WUI). Public health agencies in the states, U.S. territories, localities, and Freely Associated States are primarily responsible for detecting and investigating outbreaks and reporting them voluntarily to CDC by a standard form. Only data on outbreaks associated with drinking water, WNID (excluding recreational water), and WUI are summarized in this report. Outbreaks associated with recreational water are reported separately. A total of 24 states and Puerto Rico reported 48 outbreaks that occurred during 2007--2008. Of these 48 outbreaks, 36 were associated with drinking water, eight with WNID, and four with WUI. The 36 drinking water--associated outbreaks caused illness among at least 4,128 persons and were linked to three deaths. Etiologic agents were identified in 32 (88.9%) of the 36 drinking water--associated outbreaks; 21 (58.3%) outbreaks were associated with bacteria, five (13.9%) with viruses, three (8.3%) with parasites, one (2.8%) with a chemical, one (2.8%) with both bacteria and viruses, and one (2.8%) with both bacteria and parasites. Four outbreaks (11.1%) had unidentified etiologies. Of the 36 drinking water--associated outbreaks, 22 (61.1%) were outbreaks of

  5. Evolution of the water chemistry of Lake Orta after liming

    Directory of Open Access Journals (Sweden)

    Gabriele A. TARTARI

    2001-02-01

    Full Text Available Since 1963 Lake Orta has been an emblematic case of industrial pollution by heavy metals and acidifying compounds (ammonium sulphate, to the extent that up to 1989 it was the largest acidified deep lake in the world. The low pH values of between 3.9 and 4.4 helped to keep high the levels of toxic compounds in solution, such as copper, aluminium, zinc and nickel. The liming performed in 1989-1990 brought the pH back to neutral values, determining the precipitation of the metals and the recovery of normal chemical conditions. The main results of researches conducted continuously on the lake water chemistry from 1988 to March 2000 are as follows. The whole water mass has been completely neutralised since the beginning of 1991; pH subsequently rose until in 1999-2000 it reached the values (6.7-6.9 units of the years when the lake was in a natural condition. The alkaline reserve showed a continuous increase after the lake water was neutralised, until March 2000, when total alkalinity values levelled off at 0.19 meq l-1. The increase in pH has allowed a full recovery of nitrification processes; in fact, during the liming period the concentration of ammonium was drastically reduced, by over 80%; ammonium has been practically absent since the end of 1992, and it may be affirmed that the primary cause of the acidification of the lake has been completely removed. The nitrate content in the lake has almost halved compared with the mean concentrations measured before the liming; in March 2000 mean values of 2.0 mg N l-1 were measured, and it is likely that these values will fall further in the next few years, to below 1.5 mg N l-1. The concentrations of toxic metals have shown a progressive reduction, to the extent that in 1999 the content of copper and aluminium was close to zero in the whole water mass. The situation of Lake Orta has therefore improved enormously, and is now very similar to the original condition of the lake before it was polluted

  6. Enhanced communication and coordination in the public health surveillance component of the Cincinnati Drinking Water Contamination Warning System.

    Science.gov (United States)

    Dangel, Chrissy; Allgeier, Steven C; Gibbons, Darcy; Haas, Adam; Simon, Katie

    2012-03-01

    Effective communication and coordination are critical when investigating a possible drinking water contamination incident. A contamination warning system is designed to detect water contamination by initiating a coordinated, effective response to mitigate significant public health and economic consequences. This article describes historical communication barriers during water contamination incidents and discusses how these barriers were overcome through the public health surveillance component of the Cincinnati Drinking Water Contamination Warning System, referred to as the "Cincinnati Pilot." By enhancing partnerships in the public health surveillance component of the Cincinnati Pilot, information silos that existed in each organization were replaced with interagency information depots that facilitated effective decision making.

  7. Surveillance and monitoring of fluorides in public drinking water: a systematic review

    Directory of Open Access Journals (Sweden)

    Ceci Queluz Venturini

    2016-11-01

    Full Text Available Fluoride can harm or protect human dentition according to its concentration in the water. This paper summarizes major methodological features and main findings described in studies of fluoride concentration in public supply water that were published in specialized journals between 2008 and 2012, highlighting their implications for public health surveillance. A systematic review was conducted comprising scientific articles in the databases Embase, Lilacs and PubMed. Thirty-six studies were included: 28 from the Americas, five from Asia, two from Africa and one from Europe. The variability of the studies related to design and methodological procedures was high. Although the studies provided information on the space-temporal distribution of the samples, few publications described the population covered by the investigated supply source. Almost half of the studies were cross-sectional and no dispersion or variation measure was associated to the mean value. The electrometric method and dichotomous classification of the samples were predominately used for evaluating the outcomes. Less than half of the studies were articulated to surveillance as a State action and a lesser number raised hypotheses regarding possible factors related to the findings. There is a major space to be narrowed between the results of these initiatives and the use of that information by public health authorities and to improve methodological procedures in future studies. The interaction between researchers and water quality control organizations should be increased.

  8. Characteristics of meaningful chemistry education - The case of water quality

    NARCIS (Netherlands)

    Westbroek, Hanna Barbara

    2005-01-01

    This thesis addresses the question of how to involve students in meaningful chemistry education by a proper implementation of three characteristics of meaningful: a context, a need-to-know approach and attention for student input. The characteristics were adopted as solution strategies for

  9. Surveillance for Waterborne Disease Outbreaks Associated with Drinking Water - United States, 2013-2014.

    Science.gov (United States)

    Benedict, Katharine M; Reses, Hannah; Vigar, Marissa; Roth, David M; Roberts, Virginia A; Mattioli, Mia; Cooley, Laura A; Hilborn, Elizabeth D; Wade, Timothy J; Fullerton, Kathleen E; Yoder, Jonathan S; Hill, Vincent R

    2017-11-10

    Provision of safe water in the United States is vital to protecting public health (1). Public health agencies in the U.S. states and territories* report information on waterborne disease outbreaks to CDC through the National Outbreak Reporting System (NORS) (https://www.cdc.gov/healthywater/surveillance/index.html). During 2013-2014, 42 drinking water-associated † outbreaks were reported, accounting for at least 1,006 cases of illness, 124 hospitalizations, and 13 deaths. Legionella was associated with 57% of these outbreaks and all of the deaths. Sixty-nine percent of the reported illnesses occurred in four outbreaks in which the etiology was determined to be either a chemical or toxin or the parasite Cryptosporidium. Drinking water contamination events can cause disruptions in water service, large impacts on public health, and persistent community concern about drinking water quality. Effective water treatment and regulations can protect public drinking water supplies in the United States, and rapid detection, identification of the cause, and response to illness reports can reduce the transmission of infectious pathogens and harmful chemicals and toxins.

  10. Water chemistry and endangered white-clawed Crayfish: a literature review and field study of water chemistry association in Austropotamobius pallipes

    Directory of Open Access Journals (Sweden)

    Haddaway N.R.

    2015-01-01

    Full Text Available Populations of the endangered white-clawed crayfish (Austropotamobius pallipes have rapidly declined in distribution and density in recent decades as a result of invasive crayfish, disease and habitat degradation. The species is thought to be particularly sensitive to water chemistry, and has been proposed as a bio-indicator of water quality. Here we detail the results of a systematic review of the literature regarding the chemistry of waterbodies inhabited by white-clawed crayfish, along with a wide-scale field study of the chemistry of crayfish-inhabited waterbodies in the UK. We use these data to examine potentially significant variables influencing crayfish distribution. Several variables appear to have thresholds that affect crayfish distribution; crayfish presence was associated with high dissolved oxygen, low conductivity, ammonium, sodium, and phosphate, and to a lesser extent low sulphate, nitrate, and total suspended solids. Some variables (magnesium, potassium, sodium, sulphate, nitrate, and total suspended solids may be tolerated at moderate to high concentrations in isolation (indicated by the presence of some populations in high levels of these variables, but suites of chemical conditions may act synergistically in situ and must be considered together. Recent efforts to conserve white-clawed crayfish have included relocations to Ark Sites; novel protected habitats with reduced risk of the introduction of disease, invasive crayfish and habitat degradation. We use our findings to propose the first detailed guidelines for common water chemistry variables of potential Ark Sites for the conservation of the species throughout its European range.

  11. Water chemistry of the secondary circuit at a nuclear power station with a VVER power reactor

    Science.gov (United States)

    Tyapkov, V. F.; Erpyleva, S. F.

    2017-05-01

    Results of implementation of the secondary circuit organic amine water chemistry at Russian nuclear power plant (NPP) with VVER-1000 reactors are presented. The requirements for improving the reliability, safety, and efficiency of NPPs and for prolonging the service life of main equipment items necessitate the implementation of new technologies, such as new water chemistries. Data are analyzed on the chemical control of power unit coolant for quality after the changeover to operation with the feed of higher amines, such as morpholine and ethanolamine. Power units having equipment containing copper alloy components were converted from the all-volatile water chemistry to the ethanolamine or morpholine water chemistry with no increase in pH of the steam generator feedwater. This enables the iron content in the steam generator feedwater to be decreased from 6-12 to 2.0-2.5 μg/dm3. It is demonstrated that pH of high-temperature water is among the basic factors controlling erosion and corrosion wear of the piping and the ingress of corrosion products into NPP steam generators. For NPP power units having equipment whose construction material does not include copper alloys, the water chemistries with elevated pH of the secondary coolant are adopted. Stable dosing of correction chemicals at these power units maintains pH25 of 9.5 to 9.7 in the steam generator feedwater with a maximum iron content of 2 μg/dm3 in the steam generator feedwater.

  12. Reconnaissance of hydrology, land use, ground-water chemistry, and effects of land use on ground-water chemistry in the Albuquerque-Belen basin, New Mexico

    Science.gov (United States)

    Anderholm, S.K.

    1987-01-01

    In 1984, the U.S. Geological Survey began regional assessments of groundwater contamination in 14 areas, one of which was the Albuquerque-Belen basin. Groundwater recharge occurs along the basin margins. Groundwater discharge occurs as evapotranspiration in the Rio Grande valley, pumpage, and groundwater flow to the Socorro basin. Open-space land use, which primarily is used for grazing livestock, occupies the majority of the basin. In the Rio Grande valley, agricultural and residential land uses are predominant; in the area near Albuquerque, the land also is used for commercial, institutional , and industrial purposes. The Albuquerque-Belen basin was divided into seven zones on the basis of water chemistry. These water-chemistry zones indicate that large variations in water chemistry exist in the basin as the result of natural processes. Groundwater in the majority of the Albuquerque-Belen basin has a relatively low susceptibility to contamination because the depth to water is > 100 ft and there is virtually no natural mechanism for recharge to the groundwater system. Groundwater in the Rio Grande valley has a relatively high susceptibility to contamination because the depth to water is generally oxygen demand, and chemical oxygen demand. The constituents in the onsite waste-disposal effluent could cause reducing conditions in the aquifer and the subsequent dissolution of iron and manganese oxides. Trace metals adsorbed to these iron and manganese oxides could be remobilized in groundwater after dissolution of the oxides. (Author 's abstract)

  13. Water chemistry of surface waters affected by the Fourmile Canyon wildfire, Colorado, 2010-2011

    Science.gov (United States)

    McCleskey, R. Blaine; Writer, Jeffrey H.; Murphy, Sheila F.

    2012-01-01

    In September 2010, the Fourmile Canyon fire burned about 23 percent of the Fourmile Creek watershed in Boulder County, Colo. Water-quality sampling of Fourmile Creek began within a month after the wildfire to assess its effects on surface-water chemistry. Water samples were collected from five sites along Fourmile Creek (above, within, and below the burned area) monthly during base flow, twice weekly during snowmelt runoff, and at higher frequencies during storm events. Stream discharge was also monitored. Water-quality samples were collected less frequently from an additional 6 sites on Fourmile Creek, from 11 tributaries or other inputs, and from 3 sites along Boulder Creek. The pH, electrical conductivity, temperature, specific ultraviolet absorbance, total suspended solids, and concentrations (dissolved and total) of major cations (calcium, magnesium, sodium, and potassium), anions (chloride, sulfate, alkalinity, fluoride, and bromide), nutrients (nitrate, ammonium, and phosphorus), trace metals (aluminum, arsenic, boron, barium, beryllium, cadmium, cobalt, chromium, copper, iron, mercury, lithium, manganese, molybdenum, nickel, lead, rubidium, antimony, selenium, strontium, vanadium, and zinc), and dissolved organic carbon are here reported for 436 samples collected during 2010 and 2011.

  14. [Surveillance of drinking-water quality: assessing the degree of implementation of actions].

    Science.gov (United States)

    Guzman, Blanca Lisseth Barragan; Tovar, Gerardo Nava; Bevilacqua, Paula Dias

    2014-10-01

    This study aims to evaluate the Drinking-Water Quality Surveillance Programme (DWQS) implemented in Colombia. The study was conducted using methodology for assessing the implementation, integrating a normative assessment and evaluation research. For this assessment, Delphi methodology was developed that allowed the definition of an evaluation matrix, composed of 14 attributes and 62 criteria, as well as the building of a score system and parameters that permitted the evaluation of each of the defined criteria. Data collection involved conducting semi-structured interviews with institutional actors from 39 territorial units. The system evaluation showed that the DWQS in Colombia is partially implemented, with different stages of implementation in territorial units. The system showed a strengthening in actions related to data production on the aspect for improving water quality and DWQS actions from the standpoint of health promotion. However, some conceptual limitations were identified in terms of legislation thereby affecting the fulfilment of the universality of DWQS actions.

  15. Stepwise Inquiry into Hard Water in a High School Chemistry Laboratory

    Science.gov (United States)

    Kakisako, Mami; Nishikawa, Kazuyuki; Nakano, Masayoshi; Harada, Kana S.; Tatsuoka, Tomoyuki; Koga, Nobuyoshi

    2016-01-01

    This study focuses on the design of a learning program to introduce complexometric titration as a method for determining water hardness in a high school chemistry laboratory. Students are introduced to the different properties and reactions of hard water in a stepwise manner so that they gain the necessary chemical knowledge and conceptual…

  16. Fine scale variations of surface water chemistry in an ephemeral to perennial drainage network

    Science.gov (United States)

    Margaret A. Zimmer; Scott W. Bailey; Kevin J. McGuire; Thomas D. Bullen

    2013-01-01

    Although temporal variation in headwater stream chemistry has long been used to document baseline conditions and response to environmental drivers, less attention is paid to fine scale spatial variations that could yield clues to processes controlling stream water sources. We documented spatial and temporal variation in water composition in a headwater catchment (41 ha...

  17. Spatial And Temporal Variation In The Dissolved Trace Element Chemistry Of Chesapeake Bay Surface Waters

    Science.gov (United States)

    Dorval, E.; Hannigan, R.; Jones, C.

    2001-12-01

    Surface waters were collected from sea grass beds around the Chesapeake Bay of Virginia as well as from the mouths of the York, James, Potomac and Rappahannock rivers and Tangier and Smith islands. These sea grass beds represent the nursery habitats for a variety of sport fish including Spotted Sea Trout and Weakfish. Trace element ratios of fish otoliths record the unique chemistries of bodies of water in which the fish live. The data presented here represent the initial results of a "ground-truthing" investigation of the relationships between the water and otolith chemistry. Waters were collected bi-monthly (July through September) from 30 sites around the western and eastern shore of Chesapeake Bay including major tributaries and Tangier and Smith islands. Water was collected using trace metal clean procedures including filtration through a 0.45 uM filter and acidification in the field to pH pH and dissolved oxygen likely related to a restricted flow regime between the islands and the eastern shore. Mg/Ca and Sr/Ca ratios are unique for the sea grass beds along the western shore and allow the distinction of beds located between the York and Rappahannock rivers from those between the Rappahannock and Potomac rivers. Sr and Ba concentrations are variable between sites along the eastern shore. U, Th, Sr, and Ba fall along a mixing trajectory defined by variations in salinity from river mouth to open Bay. The preliminary results from this study indicate that the water chemistry of the sea grass beds is sufficiently variable, both in space and time. This variability in water chemistry further supports the use of otolith chemistry as a natural tag for water chemistry.

  18. Microbial Surveillance of Potable Water Sources of the International Space Station

    Science.gov (United States)

    Bruce, Rebekah J.; Ott, C. Mark; Skuratov, Vladimir M.; Pierson, Duane L.

    2005-01-01

    To mitigate risk to the crew, the microbial surveillance of the quality of potable water sources of the International Space Station (ISS) has been ongoing since before the arrival of the first permanent crew. These water sources have included stored ground-supplied water, water produced by the shuttle fuel cells during flight, and ISS humidity condensate that is reclaimed and processed. Monitoring was accomplished using a self-contained filter designed to allow bacterial growth and enumeration during flight. Upon return to earth, microbial isolates were identified using 16S ribosomal gene sequencing. While the predominant isolates were common Gramnegative bacteria including Ralstonia eutropha, Methylobacterium fujisawaense, and Spingomonas paucimobilis, opportunistic pathogens such as Stenotrophomonas maltophilia and Pseudomonas aeruginosa were also isolated. Results of in-flight enumeration have indicated a fluctuation of bacterial counts above system design specifications. Additional in-flight monitoring capability for the specific detection of coliforms was added in 2004; no coliforms have been detected from any potable water source. Neither the bacterial concentrations nor the identification of the isolates recovered from these samples has suggested a threat to crew health.

  19. Supercritical water loop design for corrosion and water chemistry tests under irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Ruzickova, Mariana; Hajek, Petr; Vsolak, Rudolf; Kysela, Jan [Nuclear Research Institute Rez plc, Reactor Services Division, Husinec (Czech Republic); Smida, Stepan [H and D Engineering, Praha (Czech Republic); Petr, Jan [Nuclear Research Institute Rez plc, Praha (Czech Republic)

    2008-03-15

    An experimental loop operating with water at supercritical conditions (25MPa, 600 .deg. C in the test section) is designed for operation in the research reactor LVR-15 in UJV Rez, Czech Republic. The loop should serve as an experimental facility for corrosion tests of materials for in-core as well as out-of-core structures, for testing and optimization of suitable water chemistry for a future HPLWR and for studies of radiolysis of water at supercritical conditions, which remains the domain where very few experimental data are available. At present, final necessary calculations (thermalhydraulic, neutronic, strength) are being performed on the irradiation channel, which is the most challenging part of the loop. The concept of the primary and auxiliary circuits has been completed. The design of the loop shall be finished in the course of the year 2007 to start the construction, out-of-pile testing to verify proper functioning of all systems and as such to be ready for in-pile tests by the end of the HPLWR Phase 2 European project by the end of 2009.

  20. Chemistry of spring and well waters on Kilauea Volcano, Hawaii, and vicinity

    Energy Technology Data Exchange (ETDEWEB)

    Janik, C.J.; Nathenson, M.; Scholl, M.A.

    1994-12-31

    Published and new data for chemical and isotopic samples from wells and springs on Kilauea Volcano and vicinity are presented. These data are used to understand processes that determine the chemistry of dilute meteoric water, mixtures with sea water, and thermal water. Data for well and spring samples of non-thermal water indicate that mixing with sea water and dissolution of rock from weathering are the major processes that determine the composition of dissolved constituents in water. Data from coastal springs demonstrate that there is a large thermal system south of the lower east rift of Kilauea. Samples of thermal water from shallow wells in the lower east rift and vicinity have rather variable chemistry indicating that a number of processes operate in the near surface. Water sampled from the available deep wells is different in composition from the shallow thermal water, indicating that generally there is not a significant component of deep water in the shallow wells. Data for samples from available deep wells show significant gradients in chemistry and steam content of the reservoir fluid. These gradients are interpreted to indicate that the reservoir tapped by the existing wells is an evolving vapor-dominated system.

  1. Chemistry and movement of ground water, Nevada Test Site

    Science.gov (United States)

    Schoff, S.L.; Moore, J.E.

    1964-01-01

    Three chemical types of ground water are distinguished at the Nevada Test Site and vicinity. A sodium-potassium water is related to tuff (in part zeolitized) and to alluvium containing detrital tuff. A calcium-magnesium water is related to limestone and dolomite, or to alluvium containing detritus of these rock types. A mixed chemical type, containing about as much sodium and potassium as calcium and magnesium, may result from the addition of one of the first two types of water to the other; to passage of water first through tuff and then through carbonate rock, or vice versa; and to ion-exchange during water travel. Consideration of the distribution of these water types, together with the distribution of sodium in the water and progressive changes in the dissolved solids, suggests that the ground water in the Nevada Test Site probably moves toward the Amargosa Desert, not into Indian Spring Valley and thence southeastward toward Las Vegas. The low dissolved solids content of ground-water reservoirs in alluvium and tuff of the enclosed basins indicates that recharge is local in origin.

  2. Ground-water, surface-water, and water-chemistry data, Black Mesa area, northeastern Arizona--2003-04

    Science.gov (United States)

    Truini, Margot; Macy, Jamie P.; Porter, Thomas J.

    2005-01-01

    The N aquifer is the major source of water in the 5,400-square-mile area of Black Mesa in northeastern Arizona. Availability of water is an important issue in this area because of continued industrial and municipal use, a growing population, and precipitation of about 6 to 14 inches per year. The monitoring program in the Black Mesa area has been operating since 1971 and is designed to determine the long-term effects of ground-water withdrawals from the N aquifer for industrial and municipal uses. The monitoring program includes measurements of (1) ground-water pumping, (2) ground-water levels, (3) spring discharge, (4) surface-water discharge, (5) ground-water chemistry, and (6) periodic testing of ground-water withdrawal meters. In 2003, total ground-water withdrawals were 7,240 acre-feet, industrial withdrawals were 4,450 acre-feet, and municipal withdrawals were 2,790 acre-feet. From 2002 to 2003, total withdrawals decreased by 10 percent, industrial withdrawals decreased by 4 percent, and municipal withdrawals decreased by 20 percent. Flowmeter testing was completed for 24 municipal wells in 2004. The median difference between pumping rates for the permanent meter and a test meter for all the sites tested was -2.9 percent. Values ranged from -10.9 percent at Forest Lake NTUA 1 to +7.8 percent at Rough Rock NTUA 2. From 2003 to 2004, water levels declined in 6 of 12 wells in the unconfined part of the aquifer, and the median change was -0.1 foot. Water levels declined in 7 of 11 wells in the confined part of the aquifer, and the median change was -2.7 feet. From the prestress period (prior to 1965) to 2003, the median water-level change for 26 wells was -23.2 feet. Median water-level change were -6.1 feet for 14 wells in the unconfined parts of the aquifer and and -72.1 feet for 12 wells in the confined part. Discharges were measured once in 2003 and once in 2004 at four springs. Discharge stayed the same at Pasture Canyon Spring, increased 9 percent at

  3. Technical note: An inorganic water chemistry dataset (1972–2011 ...

    African Journals Online (AJOL)

    A national dataset of inorganic chemical data of surface waters (rivers, lakes, and dams) in South Africa is presented and made freely available. The dataset comprises more than 500 000 complete water analyses from 1972 up to 2011, collected from more than 2 000 sample monitoring stations in South Africa. The dataset ...

  4. The Physico-chemistry and Distribution of Water Hyacinth ...

    African Journals Online (AJOL)

    The physicochemical studies and phytochemical investigations of River Nun and the water hyacinth (Eichhornia crassipes) were carried out in relation to the distribution of Eichhornia crassipes (Mart) Solms, Family Pontederiaceae in the River Nun.. The physicochemical studies of the water showed that dissolved oxygen ...

  5. Sampling procedure for lake or stream surface water chemistry

    Science.gov (United States)

    Robert Musselman

    2012-01-01

    Surface waters collected in the field for chemical analyses are easily contaminated. This research note presents a step-by-step detailed description of how to avoid sample contamination when field collecting, processing, and transporting surface water samples for laboratory analysis.

  6. Chemistry of snow and lake water in Antarctic region

    Indian Academy of Sciences (India)

    Surface snow and lake water samples were collected at different locations around Indian station at Antarctica, Maitri, during December 2004-March 2005 and December 2006-March 2007.Samples were analyzed for major chemical ions. It is found that average pH value of snow is 6.1. Average pH value of lake water with ...

  7. Microbiological surveillance and state of the art technological strategies for the prevention of dialysis water pollution.

    Science.gov (United States)

    Bolasco, Piergiorgio; Contu, Antonio; Meloni, Patrizia; Vacca, Dorio; Galfrè, Andrea

    2012-08-01

    The present report attempts to illustrate the positive impact on the microbiological quality of dialysis patients over a 15-year period through the progressive implementation of state-of-the-art technological strategies and the optimization of microbiological surveillance procedures in five dialysis units in Sardinia. Following on better microbiological, quality controls of dialysis water and improvement of procedures and equipment, a drastic improvement of microbiological water quality was observed in a total of 945 samples. The main aim was to introduce the use of microbiological culture methods as recommended by the most important guidelines. The microbiological results obtained have led to a progressive refining of controls and introduction of new materials and equipment, including two-stage osmosis and piping distribution rings featuring a greater capacity to prevent biofilm adhesion. The actions undertaken have resulted in unexpected quality improvements. Dialysis water should be viewed by the nephrologist as a medicinal product exerting a demonstrable positive impact on microinflammation in dialysis patients. A synergic effort between nephrologists and microbiologists undoubtedly constitutes the most effective means of preventing dialysis infections.

  8. Relative Effects of Water Chemistry on Aspects of Iron Corrosion

    OpenAIRE

    Zhang, Yan

    2005-01-01

    The net present replacement value of all publicly and privately owned potable water pipes in the U.S. is on the order of $2.4 trillion dollars, and costs associated with deteriorating iron pipes is billions of dollars per year. Problems arising from iron corrosion include reduced lifetime of the material, scale buildup and energy loss, nonuniform corrosion and leaks, catastrophic failure, "red water," disinfectant loss and bacterial re-growth. Iron corrosion is a very complicat...

  9. Results of ground-water, surface-water, and water-chemistry monitoring, Black Mesa area, northeastern Arizona, 1994

    Science.gov (United States)

    Littin, G.R.; Monroe, S.A.

    1995-01-01

    The Black Mesa monitoring program is designed to document long-term effects of ground-water pumping from the N aquifer by industrial and municipal users. The N aquifer is the major source of water in the 5,400-square-mile Black Mesa area, and the ground water occurs under confined and unconfined conditions. Monitoring activities include continuous and periodic measurements of (1) ground-water pumpage from the confined and unconfined areas of the aquifer, (2) ground-water levels in the confined and unconfined areas of the aquifer, (3) surface-water discharge, and (4) chemistry of the ground water and surface water. In 1994, ground-water withdrawals for industrial and municipal use totaled about 7,000 acre-feet, which is an 8-percent increase from the previous year. Pumpage from the confined part of the aquifer increased by about 9 percent to 5,400 acre-feet, and pumpage from the unconfined part of the aquifer increased by about 2 percent to 1,600 acre-feet. Water-level declines in the confined area during 1994 were recorded in 10 of 16 wells, and the median change was a decline of about 2.3 feet as opposed to a decline of 3.3 feet for the previous year. The median change in water levels in the unconfined area was a rise of 0.1 foot in 1994 as opposed to a decline of 0.5 foot in 1993. Measured low-flow discharge along Moenkopi Wash decreased from 3.0 cubic feet per second in 1993 to 2.9 cubic feet per second in 1994. Eleven low-flow measurements were made along Laguna Creek between Tsegi, Arizona, and Chinle Wash to determine the amount of discharge that would occur as seepage from the N aquifer under optimal base-flow conditions. Discharge was 5.6 cubic feet per second near Tsegi and 1.5 cubic feet per second above the confluence with Chinle Wash. Maximum discharge was 5.9 cubic feet per second about 4 miles upstream from Dennehotso. Discharge was measured at three springs. The changes in discharge at Burro and Whisky Springs were small and within the uncertainty of

  10. Coagulation chemistries for silica removal from cooling tower water.

    Energy Technology Data Exchange (ETDEWEB)

    Nyman, May Devan; Altman, Susan Jeanne; Stewart, Tom

    2010-02-01

    The formation of silica scale is a problem for thermoelectric power generating facilities, and this study investigated the potential for removal of silica by means of chemical coagulation from source water before it is subjected to mineral concentration in cooling towers. In Phase I, a screening of many typical as well as novel coagulants was carried out using concentrated cooling tower water, with and without flocculation aids, at concentrations typical for water purification with limited results. In Phase II, it was decided that treatment of source or make up water was more appropriate, and that higher dosing with coagulants delivered promising results. In fact, the less exotic coagulants proved to be more efficacious for reasons not yet fully determined. Some analysis was made of the molecular nature of the precipitated floc, which may aid in process improvements. In Phase III, more detailed study of process conditions for aluminum chloride coagulation was undertaken. Lime-soda water softening and the precipitation of magnesium hydroxide were shown to be too limited in terms of effectiveness, speed, and energy consumption to be considered further for the present application. In Phase IV, sodium aluminate emerged as an effective coagulant for silica, and the most attractive of those tested to date because of its availability, ease of use, and low requirement for additional chemicals. Some process optimization was performed for coagulant concentration and operational pH. It is concluded that silica coagulation with simple aluminum-based agents is effective, simple, and compatible with other industrial processes.

  11. Water chemistry of secondary circuit and SG currently status NPP 'Kozloduy' 3

    Energy Technology Data Exchange (ETDEWEB)

    Minkova, K. [Kozloduy NPP (Bulgaria)

    2002-07-01

    The author gives a historical review of the secondary water chemistry regimes of NPP Kozloduy Unit 3. Results of eddy current inspection on the steam generator of Unit 5 and quantity of the deposits on the surfaces of steam generator during 1989-2001 inspections are given. (uke)

  12. Cycle water chemistry based on film forming amines at power plants: evaluation of technical guidance documents

    Science.gov (United States)

    Dyachenko, F. V.; Petrova, T. I.

    2017-11-01

    Efficiency and reliability of the equipment in fossil power plants as well as in combined cycle power plants depend on the corrosion processes and deposit formation in steam/water circuit. In order to decrease these processes different water chemistries are used. Today the great attention is being attracted to the application of film forming amines and film forming amine products. The International Association for the Properties of Water and Steam (IAPWS) consolidated the information from all over the World, and based on the research studies and operating experience of researchers and engineers from 21 countries, developed and authorized the Technical Guidance Document: “Application of Film Forming Amines in Fossil, Combined Cycle, and Biomass Power Plants” in 2016. This article describe Russian and International technical guidance documents for the cycle water chemistries based on film forming amines at fossil and combined cycle power plants.

  13. Collaborative routes to clarifying the murky waters of aqueous supramolecular chemistry

    Science.gov (United States)

    Cremer, Paul S.; Flood, Amar H.; Gibb, Bruce C.; Mobley, David L.

    2018-01-01

    On planet Earth, water is everywhere: the majority of the surface is covered with it; it is a key component of all life; its vapour and droplets fill the lower atmosphere; and even rocks contain it and undergo geomorphological changes because of it. A community of physical scientists largely drives studies of the chemistry of water and aqueous solutions, with expertise in biochemistry, spectroscopy and computer modelling. More recently, however, supramolecular chemists -- with their expertise in macrocyclic synthesis and measuring supramolecular interactions -- have renewed their interest in water-mediated non-covalent interactions. These two groups offer complementary expertise that, if harnessed, offer to accelerate our understanding of aqueous supramolecular chemistry and water writ large. This Review summarizes the state-of-the-art of the two fields, and highlights where there is latent chemical space for collaborative exploration by the two groups.

  14. Primary water chemistry improvement for radiation exposure reduction at Japanese PWR Plants

    Energy Technology Data Exchange (ETDEWEB)

    Nishizawa, Eiichi [Omiya Technical Institute, Saitama-ken (Japan)

    1995-03-01

    Radiation exposure during the refueling outages at Japanese Pressurized Water Reactor (PWR) Plants has been gradually decreased through continuous efforts keeping the radiation dose rates at relatively low level. The improvement of primary water chemistry in respect to reduction of the radiation sources appears as one of the most important contributions to the achieved results and can be classified by the plant operation conditions as follows

  15. Understanding the interplay between water chemistry and electrochemical properties of copper

    Science.gov (United States)

    Cong, Hongbo

    The pitting behavior of UNS C11000 copper was investigated in a synthetic potable water found to cause pitting using both driven electrochemical methods and under natural conditions at OCP. The latter was monitored with coupled multi-electrode arrays (CMEA). Tests were also conducted in several HCO 3-, SO42- and Cl- containing-waters with systematic variations in the concentrations of these species. Empirical equations that forecast pitting (EPit) and repassivation (ERp) potential as a function of selected water chemistry variables were developed. OCP was a strong function of water chemistry, pH and time. Maximum OCPs were found to increase with both pH and Cl2. Empirical equations that forecast the OCP as a function of pH and Cl2 were also developed. Natural pitting was tested in different pH synthetic waters (6-10) at various Cl2 levels (0-5 ppm). The CMEA method successfully detected the formation of persistent anodes (pitting sites) in pH ≥7 synthetic waters compared to formation of switchable anodes at pH 6. A pitting factor was determined as a function of water chemistry. Pit events were statistically analyzed and potential excursions were compared to EPit and E Rp. Natural pitting events occurred on a percentage of electrodes once the OCP rose above ERp and this could be rationalized based on the statistical spread in EPit. Pits stopped growing once the OCP dropped below ERp Pitting severity increased with Cl2 level and pH. The cathodic capacity of adjacent cathodic sites as a function of water chemistry and the nature of the cathodic sites was also factored into this analysis. Lastly, the possible roles of deposited aluminum solids in pit initiation were also examined using several diagnostic methods.

  16. Water chemistry and phytoplankton field and laboratory procedures

    Energy Technology Data Exchange (ETDEWEB)

    Davis, C.O.; Simmons, M.S. (eds.)

    1979-12-01

    The purpose of this manual is to serve as a guide for persons using these techniques in water quality studies and as a written record of the methods used in this laboratory at this time. It is anticipated that the manual will be updated frequently as new methods are added and the present ones are further refined. The present methods are all used routinely and have been in regular use for a year or longer. This manual is specifically written as a guide for the collection and analysis of lake water samples from the Laurentian Great Lakes. However, all of the analytical methods are easily adapted for laboratory culture or small lake studies. The descriptions contained in this manual are designed primarily as users guides oriented to the equipment available at the Great Lakes Research Division, and as most of the methods are taken from the literature, the reader is referred to the original articles for a more detailed discussion of the methods.

  17. Water chemistry responses to hydraulic manipulation of an agricultural wetland

    Science.gov (United States)

    Powers, S.; Stanley, E. H.

    2011-12-01

    Small impoundments are often crucial factors for the movement of sediment, organic matter, water-borne nutrients, and toxic materials through river networks. By recent accounting, at least 2.6 million small artificial water bodies exist in the US alone. A large proportion of those structures occur in regions with high intensity of agriculture, such as in the Midwestern grain belt. While small impoundments are aging structures which appear to serve few purposes, some hold ecological and biogeochemical value as artificial wetlands. We documented instantaneous net fluxes of solute (chloride, sulfate, nitrate, ammonium, and soluble reactive phosphorus) through an artificial flow-through wetland in agricultural southern Wisconsin over 6 years which spanned removal of a small dam. Phased dewatering and dam removal ultimately converted the artificial wetland to a canal-like state (increase in mean water velocity from 0.08 to 0.22 m s-1). Mean net flux for chloride across the system averaged nearly 0 g d-1, indicating conservative transport and successful characterization of hydrology. In contrast, net fluxes for other solute forms were altered following loss of the wetland: a persistent net sulfate sink (5-10% of inputs retained), suggestive of sulfate-reducing bacteria, was reduced; seasonal (summer) net sinks for nitrate and ammonium, suggestive of uptake by algae and denitrifying bacteria, were reduced; temporal variability for the net flux of soluble reactive phosphorus was reduced. Overall, loss of the artificial wetland caused by dam removal shifted seasonal and annual net fluxes of biologically available solute toward export. Nutrient retention by artificial wetlands could be important for elemental budgets in regions which have high nutrient loading to surface and ground water.

  18. Bottom Sediment Chemistry, Nutrient Balance, and Water Birds in ...

    African Journals Online (AJOL)

    Water bird characteristics, nutrient loadings, and the levels of bottom sediment silicon oxide (SiO2), aluminium oxide (Al2O3), ferric oxide (Fe2O3), calcium oxide (CaO), copper (Cu), phosphorus (P) and organic carbon (C) was studied in eight high altitude (2040-2640m) small shallow (0.065-0.249 km2; 0.9-3.1 m) ...

  19. Governing chemistry of cellulose hydrolysis in supercritical water.

    Science.gov (United States)

    Cantero, Danilo A; Bermejo, M Dolores; Cocero, M José

    2015-03-01

    At extremely low reaction times (0.02 s), cellulose was hydrolyzed in supercritical water (T=400 °C and P=25 MPa) to obtain a sugar yield higher than 95 wt%, whereas the 5-hydroxymethylfurfural (5-HMF) yield was lower than 0.01 wt %. If the reaction time was increased to 1 s, the main product was glycolaldehyde (60 wt%). Independently of the reaction time, the yield of 5-HMF was always lower than 0.01 wt%. To evaluate the reaction mechanism of biomass hydrolysis in pressurized water, several parameters (temperature, pressure, reaction time, and reaction medium) were studied for different biomasses (cellulose, glucose, fructose, and wheat bran). It was found that the H(+) and OH(-) ion concentration in the reaction medium as a result of water dissociation is the determining factor in the selectivity. The reaction of glucose isomerization to fructose and the further dehydration to 5-HMF are highly dependent on the ion concentration. By an increase in the pOH/pH value, these reactions were minimized to allow control of 5-HMF production. Under these conditions, the retroaldol condensation pathway was enhanced, instead of the isomerization/dehydration pathway. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. The role of water chemistry and geomorphic control in the presence of Didymosphenia geminata in Quebec

    Science.gov (United States)

    Gillis, C.; Gabor, R. S.; Cullis, J. D.; Ran, L.; Hassan, M. A.

    2010-12-01

    Didymosphenia geminata (didymo), an invasive diatom, was first officially observed and identified in the Matapedia River in Eastern Quebec in July 2006. This Atlantic salmon fishing river has several characteristics shown to favor didymo's ability to form thick, extensive benthic mats, including stable flow and oligotrophic nutrient conditions. Since the incursion, rapid colonization and inter-catchment transfer processes were observed, notably in surrounding watersheds on the Gaspé Peninsula as well as in northern New-Brunswick. All affected watersheds share favorable characteristics for didymo growth, including high light, low nutrient waters, and stable substrate. The nearby North Shore of the St. Lawrence, which also contains rivers with conditions that would favor didymo growth, has not yet shown didymo presence. This system provides a comparison to identify necessary parameters for didymo growth, with differences primarily due to geology-driven water chemistry. Pre-incursion water chemistry was compared between the two regions. Rivers in the region where didymo is present displayed a high alkalinity and corresponding higher pH, due to increases concentrations of magnesium and calcium, than rivers in regions where didymo has not appeared. Also, rivers with didymo show a lower amount of color-causing compounds, such as organic carbon, and clearer water, which supports the theory that high light levels encourage didymo growth. In addition to water chemistry, channel morphology, bed stability and flow patterns are also believed to be key elements in determining the presence of this benthic diatom. In 2007, channel morphology, bed texture, bankfull depth and width, local bed slope and didymo presence were surveyed on a 65 km stretch of the Matapedia River. Relative frequency of didymo presence showed that didymo blooms are most likely to appear in cobble-riffles than in any other morphologies. In fact, cobble riffles promote didymo establishment due to shallow

  1. A spatial and seasonal assessment of river water chemistry across North West England.

    Science.gov (United States)

    Rothwell, J J; Dise, N B; Taylor, K G; Allott, T E H; Scholefield, P; Davies, H; Neal, C

    2010-01-15

    This paper presents information on the spatial and seasonal patterns of river water chemistry at approximately 800 sites in North West England based on data from the Environment Agency regional monitoring programme. Within a GIS framework, the linkages between average water chemistry (pH, sulphate, base cations, nutrients and metals) catchment characteristics (topography, land cover, soil hydrology, base flow index and geology), rainfall, deposition chemistry and geo-spatial information on discharge consents (point sources) are examined. Water quality maps reveal that there is a clear distinction between the uplands and lowlands. Upland waters are acidic and have low concentrations of base cations, explained by background geological sources and land cover. Localised high concentrations of metals occur in areas of the Cumbrian Fells which are subjected to mining effluent inputs. Nutrient concentrations are low in the uplands with the exception sites receiving effluent inputs from rural point sources. In the lowlands, both past and present human activities have a major impact on river water chemistry, especially in the urban and industrial heartlands of Greater Manchester, south Lancashire and Merseyside. Over 40% of the sites have average orthophosphate concentrations >0.1mg-Pl(-1). Results suggest that the dominant control on orthophosphate concentrations is point source contributions from sewage effluent inputs. Diffuse agricultural sources are also important, although this influence is masked by the impact of point sources. Average nitrate concentrations are linked to the coverage of arable land, although sewage effluent inputs have a significant effect on nitrate concentrations. Metal concentrations in the lowlands are linked to diffuse and point sources. The study demonstrates that point sources, as well as diffuse sources, need to be considered when targeting measures for the effective reduction in river nutrient concentrations. This issue is clearly important

  2. Kinugasa Reactions in Water: From Green Chemistry to Bioorthogonal Labelling

    Directory of Open Access Journals (Sweden)

    Mariya Chigrinova

    2015-04-01

    Full Text Available The Kinugasa reaction has become an efficient method for the direct synthesis of β-lactams from substituted nitrones and copper(I acetylides. In recent years, the reaction scope has been expanded to include the use of water as the solvent, and with micelle-promoted [3+2] cycloadditions followed by rearrangement furnishing high yields of β-lactams. The high yields of stable products under aqueous conditions render the modified Kinugasa reaction amenable to metabolic labelling and bioorthogonal applications. Herein, the development of methods for use of the Kinugasa reaction in aqueous media is reviewed, with emphasis on its potential use as a bioorthogonal coupling strategy.

  3. Dominant processes controlling water chemistry of the Pecos River in American southwest

    Science.gov (United States)

    Yuan, Fasong; Miyamoto, Seiichi

    2005-09-01

    Here we show an analysis of river flow and water chemistry data from eleven gauging stations along the Pecos River in eastern New Mexico and western Texas, with time spanning 1959-2002. Analysis of spatial relationship between the long-term average flow and total dissolved solids (TDS) concentration allows us to illuminate four major processes controlling river chemistry, namely saline water addition, evaporative concentration with salt gain or loss, dilution with salt gain or loss, and salt storage. Of the 10 river reaches studied, six reaches exhibit the process dominated by evaporative concentration or freshwater dilution with little change in salt load. Four reaches show considerable salt gains or losses that are induced by surface-ground water interactions. This analysis suggests that the evaporative concentration and freshwater dilution are the prevailing mechanisms, but local processes (e.g., variations in hydrologic flowpath and lithologic formation) also play an important role in regulating the hydrochemistry of the Pecos River.

  4. Integrating surveillance data on water-related diseases and drinking-water quality; action-research in a Brazilian municipality.

    Science.gov (United States)

    Queiroz, Ana Carolina Lanza; Cardoso, Laís Santos de Magalhães; Heller, Léo; Cairncross, Sandy

    2015-12-01

    The Brazilian Ministry of Health proposed a research study involving municipal professional staff conducting both epidemiological and water quality surveillance to facilitate the integration of the data which they collected. It aimed to improve the intersectoral collaboration and health promotion activities in the municipalities, especially regarding drinking-water quality. We then conducted a study using the action-research approach. At its evaluation phase, a technique which we called 'the tree analogy' was applied in order to identify both possibilities and challenges related to the proposed interlinkage. Results showed that integrating the two data collection systems cannot be attained without prior institutional adjustments. It suggests therefore the necessity to unravel issues that go beyond the selection and the interrelation of indicators and compatibility of software, to include political, administrative and personal matters. The evaluation process led those involved to re-think their practice by sharing experiences encountered in everyday practice, and formulating constructive criticisms. All this inevitably unleashes a process of empowerment. From this perspective, we have certainly gathered some fruit from the Tree, but not necessarily the most visible.

  5. Abrupt changes in air temperature and precipitation: Do they matter for water chemistry?

    Science.gov (United States)

    Temnerud, J.; Weyhenmeyer, G. A.

    2008-06-01

    We analyzed 120 years long time series of air temperature and precipitation from 29 respective 44 sites distributed all over Sweden and determined abrupt changes by using three methods. For air temperature we found significant changes in 1930 and 1989 and for precipitation in 1920, 1979, and 1998. Analyzing more than 30 yearlong time series of ice cover (333 sites), discharge and watercourses chemistry (87 sites), we observed abrupt changes in 1977, 1989, and 1998 for discharge but first in 1998 for watercourses chemistry, most pronounced for organic matter and sulfate concentrations. We suggest that the abrupt increase in air temperature in 1989 liberated more easily mobilized organic matter in the catchments, which, for water chemistry, was first detected in 1998 as a consequence of increased discharge. We conclude that increases in air temperatures can make ecosystems more sensitive to further changes in precipitation.

  6. Comparison of BGB-MUG and LSTB-MUG in microbiological surveillance of recreational waters.

    Science.gov (United States)

    Höller, C; Havemeister, G; Gundermann, K O

    1995-12-01

    Recreational water surveillance is an important tool to prevent health hazards for the population. Therefore distinct guide and imperative values for fecal indicators are listed in the EC directive about water quality control. The detection methods, however, give laboratories some room to choose their own method, which has led to difficulties in the comparability of results. In 1989 an ad-hoc working group of the coastal countries of Germany established detection methods, which by now are obligatory for these countries. Fecal and total coliforms (FC and TC) are detected by a triplicate mpn-procedure using brilliant green-bile-lactose broth supplemented with tryptophane and 4-methylumbelliferyl-beta-D-glucuronide (BGB-MUG) as selective medium. Gas-, fluorescence- and indole-positive cultures are considered fecal coliform-positive. In the last years rises in TC but not in FC counts were observed in fresh waters. A study was carried out to evaluate the official method in another bathing season, to determine bacterial species leading to false-positive TC cultures and to compare BGB-MUG with laurylsulphate-tryptophane-MUG (LSTB-MUG). Water samples of different salinities and nutrient input were collected in weekly intervals from April to October. FC and TC concentrations were determined and all TC-positive cultures were differentiated further. The FC counts obtained by enrichment in BGB-MUG or LSTB-MUG were nearly identical, the rate of fluorescence-positive, indole-negative tubes being approximately 0.6%. Differentiation of FC-negative cultures showed a false-negative rate of 2.87% for BGB-MUG and of 8% for LSTB-MUG. During the summer months TC counts in BGB-MUG exceeded FC counts by far at most of the sampling sites. This effect was much less pronounced in LSTB-MUG; the difference between both enrichment media being significant. Differentiation of presumptive TC from BGB-MUG resulted in a high percentage of Aeromonas spp. in fresh waters. LSTB-MUG was clearly more

  7. Spatiotemporal dynamics of spring and stream water chemistry in a high-mountain area

    Energy Technology Data Exchange (ETDEWEB)

    Zelazny, Miroslaw, E-mail: miroslaw.zelazny@uj.edu.pl [Jagiellonian University, Institute of Geography and Spatial Management, Department of Hydrology, 7 Gronostajowa Str., 30-387 Cracow (Poland); Astel, Aleksander, E-mail: astel@apsl.edu.pl [Environmental Chemistry Research Unit, Biology and Environmental Protection Institute, Pomeranian Academy, 22a Arciszewskiego Str., Slupsk, 76-200 (Poland); Wolanin, Anna [Jagiellonian University, Institute of Geography and Spatial Management, Department of Hydrology, 7 Gronostajowa Str., 30-387 Cracow (Poland); Malek, Stanislaw, E-mail: rlmalek@cyf-kr.edu.pl [Department of Forest Ecology, Forest Faculty, Agricultural University of Cracow, 46 29 Listopada Ave., Cracow, 31-425 (Poland)

    2011-05-15

    The present study deals with the application of the self-organizing map (SOM) technique in the exploration of spatiotemporal dynamics of spring and stream water samples collected in the Chocholowski Stream Basin located in the Tatra Mountains (Poland). The SOM-based classification helped to uncover relationships between physical and chemical parameters of water samples and factors determining the quality of water in the studied high-mountain area. In the upper part of the Chocholowski Stream Basin, located on the top of the crystalline core of the Tatras, concentrations of the majority of ionic substances were the lowest due to limited leaching. Significantly higher concentration of ionic substances was detected in spring and stream samples draining sedimentary rocks. The influence of karst-type springs on the quality of stream water was also demonstrated. - Highlights: > We use SOM approach to explore physiochemical data for mountain waters. > Geologic structure and hydrological events impact water chemistry. > Limited leaching, typical of crystalline core, reflects in low water mineralization. > Sedimentary rocks are susceptible for leaching. > Eutrophication has not been shown to be a threat in the Chocholowska Valley. - Spatiotemporal dynamics of spring and stream water chemistry in unique high-mountain area was evaluated by the self-organizing map technique.

  8. Geohydrological characterization, water-chemistry, and ground-water flow simulation model of the Sonoma Valley area, Sonoma County, California

    Science.gov (United States)

    Farrar, Christopher D.; Metzger, Loren F.; Nishikawa, Tracy; Koczot, Kathryn M.; Reichard, Eric G.; Langenheim, V.E.

    2006-01-01

    The Sonoma Valley, located about 30 miles north of San Francisco, is one of several basins in Sonoma County that use a combination of ground water and water delivered from the Russian River for supply. Over the past 30 years, Sonoma Valley has experienced rapid population growth and land-use changes. In particular, there has been a significant increase in irrigated agriculture, predominantly vineyards. To provide a better understanding of the ground-water/surface-water system in Sonoma Valley, the U.S. Geological Survey compiled and evaluated existing data, collected and analyzed new data, and developed a ground-water flow model to better understand and manage the ground-water system. The new data collected include subsurface lithology, gravity measurements, groundwater levels, streamflow gains and losses, temperature, water chemistry, and stable isotopes. Sonoma Valley is drained by Sonoma Creek, which discharges into San Pablo Bay. The long-term average annual volume of precipitation in the watershed is estimated to be 269,000 acre-feet. Recharge to the ground-water system is primarily from direct precipitation and Sonoma Creek. Discharge from the ground-water system is predominantly outflow to Sonoma Creek, pumpage, and outflow to marshlands and to San Pablo Bay. Geologic units of most importance for groundwater supply are the Quaternary alluvial deposits, the Glen Ellen Formation, the Huichica Formation, and the Sonoma Volcanics. In this report, the ground-water system is divided into three depth-based geohydrologic units: upper (less than 200 feet below land surface), middle (between 200 and 500 feet), and lower (greater than 500 feet). Synoptic streamflow measurements were made along Sonoma Creek and indicate those reaches with statistically significant gains or losses. Changes in ground-water levels in wells were analyzed by comparing historical contour maps with the contour map for 2003. In addition, individual hydrographs were evaluated to assess temporal

  9. On the pore water chemistry effect on spectral induced polarization measurements in the presence of pyrite

    Science.gov (United States)

    Placencia-Gómez, Edmundo; Slater, Lee D.

    2016-12-01

    In order to expand the application of the induced polarization (IP) method as a technique for monitoring metallic mineral dissolution and precipitation mechanisms, we studied the effects of variations in pore water chemistry on the spectral induced polarization (SIP) response of a mixture of silica-sand and pyrite particles in the laboratory. We investigated the dependence of the SIP response on both pore water conductivity and pH for various chemical compositions: redox-passive (P) versus redox-active (A) ions, using CaCl2 as P-ions, and FeSO4 and FeCl3 as A-ion brines. The effect of pore water chemistry was evaluated by means of a recently proposed volumetric specific capacitance model. The SIP response (IP-effect) was primarily determined by the pore water conductivity and the specific capacitance was only weakly dependent on the chemical composition and pHw. We found that the specific capacitance varies to first order over a limited range and approximates a single value (≈ 302 F m- 3 in average). However, variations in the specific capacitance as a function of active versus inactive ion chemistry might be important to consider when using IP to monitor specific mineral dissolution and precipitation processes.

  10. Simulation of stratospheric water vapor trends: impact on stratospheric ozone chemistry

    Directory of Open Access Journals (Sweden)

    A. Stenke

    2005-01-01

    Full Text Available A transient model simulation of the 40-year time period 1960 to 1999 with the coupled climate-chemistry model (CCM ECHAM4.L39(DLR/CHEM shows a stratospheric water vapor increase over the last two decades of 0.7 ppmv and, additionally, a short-term increase after major volcanic eruptions. Furthermore, a long-term decrease in global total ozone as well as a short-term ozone decline in the tropics after volcanic eruptions are modeled. In order to understand the resulting effects of the water vapor changes on lower stratospheric ozone chemistry, different perturbation simulations were performed with the CCM ECHAM4.L39(DLR/CHEM feeding the water vapor perturbations only to the chemistry part. Two different long-term perturbations of lower stratospheric water vapor, +1 ppmv and +5 ppmv, and a short-term perturbation of +2 ppmv with an e-folding time of two months were applied. An additional stratospheric water vapor amount of 1 ppmv results in a 5–10% OH increase in the tropical lower stratosphere between 100 and 30 hPa. As a direct consequence of the OH increase the ozone destruction by the HOx cycle becomes 6.4% more effective. Coupling processes between the HOx-family and the NOx/ClOx-family also affect the ozone destruction by other catalytic reaction cycles. The NOx cycle becomes 1.6% less effective, whereas the effectiveness of the ClOx cycle is again slightly enhanced. A long-term water vapor increase does not only affect gas-phase chemistry, but also heterogeneous ozone chemistry in polar regions. The model results indicate an enhanced heterogeneous ozone depletion during antarctic spring due to a longer PSC existence period. In contrast, PSC formation in the northern hemisphere polar vortex and therefore heterogeneous ozone depletion during arctic spring are not affected by the water vapor increase, because of the less PSC activity. Finally, this study shows that 10% of the global total ozone decline in the transient model run

  11. 2015 AAAR Conference Symposium: "The Role of Water in Aerosol Chemistry"

    Energy Technology Data Exchange (ETDEWEB)

    McNeill, V. Faye [Columbia Univ., New York, NY (United States); Weber, Rodney [Georgia Inst. of Technology, Atlanta, GA (United States)

    2015-10-16

    The DOE-sponsored symposium, "The Role of Water in Aerosol Chemistry" was held at the 2015 Annual meeting of AAAR. The funding supported, in part, travel, lodging, and registration expenses for invited symposium speakers, and travel and lodging expenses allowing students to attend and make presentations at a special conference symposium that focuses on topics of interest to the U.S. DOE Atmospheric System Research (ASR) program.

  12. The unique chemistry of Eastern Mediterranean water masses selects for distinct microbial communities by depth.

    Directory of Open Access Journals (Sweden)

    Stephen M Techtmann

    Full Text Available The waters of the Eastern Mediterranean are characterized by unique physical and chemical properties within separate water masses occupying different depths. Distinct water masses are present throughout the oceans, which drive thermohaline circulation. These water masses may contain specific microbial assemblages. The goal of this study was to examine the effect of physical and geological phenomena on the microbial community of the Eastern Mediterranean water column. Chemical measurements were combined with phospholipid fatty acid (PLFA analysis and high-throughput 16S rRNA sequencing to characterize the microbial community in the water column at five sites. We demonstrate that the chemistry and microbial community of the water column were stratified into three distinct water masses. The salinity and nutrient concentrations vary between these water masses. Nutrient concentrations increased with depth, and salinity was highest in the intermediate water mass. Our PLFA analysis indicated different lipid classes were abundant in each water mass, suggesting that distinct groups of microbes inhabit these water masses. 16S rRNA gene sequencing confirmed the presence of distinct microbial communities in each water mass. Taxa involved in autotrophic nitrogen cycling were enriched in the intermediate water mass suggesting that microbes in this water mass may be important to the nitrogen cycle of the Eastern Mediterranean. The Eastern Mediterranean also contains numerous active hydrocarbon seeps. We sampled above the North Alex Mud Volcano, in order to test the effect of these geological features on the microbial community in the adjacent water column. The community in the waters overlaying the mud volcano was distinct from other communities collected at similar depths and was enriched in known hydrocarbon degrading taxa. Our results demonstrate that physical phenomena such stratification as well as geological phenomena such as mud volcanoes strongly

  13. The unique chemistry of Eastern Mediterranean water masses selects for distinct microbial communities by depth.

    Science.gov (United States)

    Techtmann, Stephen M; Fortney, Julian L; Ayers, Kati A; Joyner, Dominique C; Linley, Thomas D; Pfiffner, Susan M; Hazen, Terry C

    2015-01-01

    The waters of the Eastern Mediterranean are characterized by unique physical and chemical properties within separate water masses occupying different depths. Distinct water masses are present throughout the oceans, which drive thermohaline circulation. These water masses may contain specific microbial assemblages. The goal of this study was to examine the effect of physical and geological phenomena on the microbial community of the Eastern Mediterranean water column. Chemical measurements were combined with phospholipid fatty acid (PLFA) analysis and high-throughput 16S rRNA sequencing to characterize the microbial community in the water column at five sites. We demonstrate that the chemistry and microbial community of the water column were stratified into three distinct water masses. The salinity and nutrient concentrations vary between these water masses. Nutrient concentrations increased with depth, and salinity was highest in the intermediate water mass. Our PLFA analysis indicated different lipid classes were abundant in each water mass, suggesting that distinct groups of microbes inhabit these water masses. 16S rRNA gene sequencing confirmed the presence of distinct microbial communities in each water mass. Taxa involved in autotrophic nitrogen cycling were enriched in the intermediate water mass suggesting that microbes in this water mass may be important to the nitrogen cycle of the Eastern Mediterranean. The Eastern Mediterranean also contains numerous active hydrocarbon seeps. We sampled above the North Alex Mud Volcano, in order to test the effect of these geological features on the microbial community in the adjacent water column. The community in the waters overlaying the mud volcano was distinct from other communities collected at similar depths and was enriched in known hydrocarbon degrading taxa. Our results demonstrate that physical phenomena such stratification as well as geological phenomena such as mud volcanoes strongly affect microbial

  14. Introduction of Mass Spectrometry in an First-Semester General Chemistry Laboratory Course: Quantification of Mtbe or Dmso in Water

    Science.gov (United States)

    Solow, Mike

    2004-01-01

    Quantification of a contaminant in water provides the first-year general chemistry students with a tangible application of mass spectrometry. The relevance of chemistry to assessing and solving environmental problems is highlighted for students when they perform mass spectroscopy experiments.

  15. Wildfires and water chemistry: effect of metals associated with wood ash.

    Science.gov (United States)

    Cerrato, José M; Blake, Johanna M; Hirani, Chris; Clark, Alexander L; Ali, Abdul-Mehdi S; Artyushkova, Kateryna; Peterson, Eric; Bixby, Rebecca J

    2016-08-10

    The reactivity of metals associated with ash from wood collected from the Valles Caldera National Preserve, Jemez Mountains, New Mexico, was assessed through a series of laboratory experiments. Microscopy, spectroscopy, diffraction, and aqueous chemistry measurements were integrated to determine the chemical composition of wood ash and its effect on water chemistry. Climate change has caused dramatic impacts and stresses that have resulted in large-scale increases in wildfire activity in semi-arid areas of the world. Metals and other constituents associated with wildfire ash can be transported by storm event runoff and negatively affect the water quality in streams and rivers. Differences among ash from six tree species based on total concentrations of metals such as Ca, Al, Mg, Fe, and Mn were identified using non-metric multidimensional analysis. Metal-bearing carbonate and oxide phases were quantified by X-ray diffraction analyses and X-ray spectroscopy analyses. These metal-bearing carbonate phases were readily dissolved in the first 30 minutes of reaction with 18 MΩ water and 10 mM HCO3(-) in laboratory batch experiments which resulted in the release of metals and carbonates in the ash, causing water alkalinity to increase. However, metal concentrations decreased over the course of the experiment, suggesting that metals re-adsorb to ash. Our results suggest that the dissolution of metal-bearing carbonate and oxide phases in ash and metal re-adsorption to ash are relevant processes affecting water chemistry after wildfire events. These results have important implications to better understand the impact of wildfire events on water quality.

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

    Directory of Open Access Journals (Sweden)

    Franco Tassi

    2014-05-01

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

  17. Hydrogen chloride heterogeneous chemistry on frozen water particles in subsonic aircraft plume. Laboratory studies and modelling

    Energy Technology Data Exchange (ETDEWEB)

    Persiantseva, N.V.; Popovitcheva, O.B.; Rakhimova, T.V. [Moscow State Univ. (Russian Federation)

    1997-12-31

    Heterogeneous chemistry of HCl, as a main reservoir of chlorine content gases, has been considered after plume cooling and ice particle formation. The HCl, HNO{sub 3}, N{sub 2}O{sub 5} uptake efficiencies by frozen water were obtained in a Knudsen-cell flow reactor at the subsonic cruise conditions. The formation of ice particles in the plume of subsonic aircraft is simulated to describe the kinetics of gaseous HCl loss due to heterogeneous processes. It is shown that the HCl uptake by frozen water particles may play an important role in the gaseous HCl depletion in the aircraft plume. (author) 14 refs.

  18. Understanding the Role of Water on Electron-Initiated Processes and Radical Chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Garrett, Bruce C [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Colson, Steven D [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Dixon, David A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Laufer, Allan H [US Department of Energy Office of Science Office of Basic Energy Sciences; Ray, Douglas [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2003-06-10

    On September 26–28, 2002, a workshop entitled “Understanding the Role of Water on Electron-Initiated Processes and Radical Chemistry” was held to assess new research opportunities in electron-driven processes and radical chemistry in aqueous systems. Of particular interest was the unique and complex role that the structure of water plays in influencing these processes. Novel experimental and theoretical approaches to solving long-standing problems in the field were explored. A broad selection of participants from universities and the national laboratories contributed to the workshop, which included scientific and technical presentations and parallel sessions for discussions and report writing.

  19. Evolution of water chemistry during Marcellus Shale gas development: A case study in West Virginia.

    Science.gov (United States)

    Ziemkiewicz, Paul F; Thomas He, Y

    2015-09-01

    Hydraulic fracturing (HF) has been used with horizontal drilling to extract gas and natural gas liquids from source rock such as the Marcellus Shale in the Appalachian Basin. Horizontal drilling and HF generates large volumes of waste water known as flowback. While inorganic ion chemistry has been well characterized, and the general increase in concentration through the flowback is widely recognized, the literature contains little information relative to organic compounds and radionuclides. This study examined the chemical evolution of liquid process and waste streams (including makeup water, HF fluids, and flowback) in four Marcellus Shale gas well sites in north central West Virginia. Concentrations of organic and inorganic constituents and radioactive isotopes were measured to determine changes in waste water chemistry during shale gas development. We found that additives used in fracturing fluid may contribute to some of the constituents (e.g., Fe) found in flowback, but they appear to play a minor role. Time sequence samples collected during flowback indicated increasing concentrations of organic, inorganic and radioactive constituents. Nearly all constituents were found in much higher concentrations in flowback water than in injected HF fluids suggesting that the bulk of constituents originate in the Marcellus Shale formation rather than in the formulation of the injected HF fluids. Liquid wastes such as flowback and produced water, are largely recycled for subsequent fracturing operations. These practices limit environmental exposure to flowback. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. INLAND DISSOLVED SALT CHEMISTRY: STATISTICAL EVALUATION OF BIVARIATE AND TERNARY DIAGRAM MODELS FOR SURFACE AND SUBSURFACE WATERS

    Science.gov (United States)

    We compared the use of ternary and bivariate diagrams to distinguish the effects of atmospheric precipitation, rock weathering, and evaporation on inland surface and subsurface water chemistry. The three processes could not be statistically differentiated using bivariate models e...

  1. Hydrogeology and water chemistry of Infranz catchment springs, Bahir Dar Area, Lake Tana Basin, Ethiopia

    Science.gov (United States)

    Abera, F. N.; Vancamp, M.; Walraevens, K.

    2016-12-01

    ABSTRACT The major springs in the Infranz catchment are a significant source of water for Bahir city and nearby villages, while they help to sustain Infranz River and the downstream wetlands. The aim of the research was to understand the hydrogeological conditions of these high-discharge springs, and to explain the hydrochemical composition of spring waters. Water samples from rainwater and springs were collected and analyzed and compared for major cations and anions. The hydrochemical data analysis showed that all water samples of the springs have freshwater chemistry, Ca-HCO3 type, while deep groundwater shows more evolved types. This indicates limited water-rock interaction and short residence time for the spring waters. The rise of NO3- and PO43- may indicate future water quality degradation unless the anthropogenic activities upgradient and nearby are restricted. The uptake of 75% of spring water for water supply of Bahir Dar results in wetland degradation. Key words: Spring water, Infranz River, Bahir Dar, Ethiopia, hydrochemistry

  2. The development of a neutralizing amines based reagent for maintaining the water chemistry for medium and high pressures steam boilers

    Science.gov (United States)

    Butakova, M. V.; Orlov, K. A.; Guseva, O. V.

    2017-11-01

    An overview of the development for neutralizing amine based reagent for water chemistry of steam boilers for medium and high pressures was given. Total values of the neutralization constants and the distribution coefficients of the compositions selected as a main criteria for reagent composition. Experimental results of using this new reagent for water chemistry in HRSG of power plant in oil-production company are discussed.

  3. Effects of Chemistry Parameters of Primary Water affecting Leakage of Steam Generator Tube Cracks

    Energy Technology Data Exchange (ETDEWEB)

    Shin, D. M.; Cho, N. C.; Kang, Y. S.; Lee, K. H. [KHNP CRI, Daejeon (Korea, Republic of)

    2016-10-15

    Degradation of steam generator (SG) tubes can affect pressure boundary tightness. As a defense-in-depth measure, primary to secondary leak monitoring program for steam generators is implemented, and operation is allowed under leakage limits in nuclear power plants. Chemistry parameters that affect steam generator tube leakage due to primary water stress corrosion cracking (PWSCC) are investigated in this study. Tube sleeves were installed to inhibit leakage and improve tube integrity as a part of maintenance methods. Steam generators occurred small leak during operation have been replaced with new steam generators according to plant maintenance strategies. The correlations between steam generator leakage and chemistry parameters are presented. Effects of primary water chemistry parameters on leakage from tube cracks were investigated for the steam generators experiencing small leak. Unit A experienced small leakage from steam generator tubes in the end of operation cycle. It was concluded that increased solubility of oxides due to high pHT could make leakage paths, and low boron concentration lead to less blockage in cracks. Increased dissolved hydrogen may retard crack propagations, but it did not reduce leak rate of the leaking steam generator. In order to inhibit and reduce leakage, pH{sub T} was controlled by servicing cation bed operation. The test results of decreasing pHT indicate low pHT can reduce leak rate of PWSCC cracks in the end of cycle.

  4. Changing carbonate chemistry in ocean waters surrounding coral reefs in the CMIP5 ensemble

    Science.gov (United States)

    Ricke, K.; Schneider, K.; Cao, L.; Caldeira, K.

    2012-12-01

    Coral reefs comprise some of the most biodiverse ecosystems in the world. Today they are threatened by a number of stressors, including pollution, bleaching from global warming and ocean acidification. In this study, we focus on the implications of ocean acidification for the open ocean chemistry surrounding coral reefs. We use results from 13 Earth System Models included in the Coupled Model Intercomparison Project 5 (CMIP5) to examine the changing aragonite saturations (Ωa) of open ocean waters surrounding approximately 6,000 coral reefs. These 13 Earth System Models participating in CMIP5 each have interactive ocean biogeochemistry models that output state variables including DIC, alkalinity, SST, and salinity. Variation in these values were combined with values from the GLODAP database to calculate aragonite, the form of calcium carbonate that corals use to make their skeletons. We used reef locations from ReefBase that were within one degree (in latitude or longitude) of water masses represented both in the GLODAP database and in the climate models. Carbonate chemistry calculations were performed by Dr. James C. Orr (IPSL) as part of a separate study. We find that in preindustrial times, 99.9 % of coral reefs were located in regions of the ocean with aragonite saturations of 3.5 or more. The saturation threshold for viable reef ecosystems in uncertain, but the pre-industrial distribution of water chemistry surrounding coral reefs may nevertheless provide some indication of viability. We examine the fate of coral reefs in the context of several potential aragonite saturation thresholds, i.e., when Ωa_crit equals 3, 3.25, or 3.5. We show that under a business-as-usual scenario Representative Concentration Pathway (RCP) 8.5, the specific value of Ωa_crit does not affect the long-term fate of coral reefs -- by the end of the 21st century, no coral reef considered is surrounded by water with Ωa> 3. However, under scenarios with significant CO2 emissions

  5. Groundwater fluxes into a submerged sinkhole area, Central Italy, using radon and water chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Tuccimei, P. [Dipartimento di Scienze Geologiche, Universita ' Roma Tre' , Largo San Leonardo Murialdo 1, 00146 Rome (Italy)]. E-mail: tuccimei@uniroma3.it; Salvati, R. [Dipartimento di Scienze Geologiche, Universita ' Roma Tre' , Largo San Leonardo Murialdo 1, 00146 Rome (Italy); Capelli, G. [Dipartimento di Scienze Geologiche, Universita ' Roma Tre' , Largo San Leonardo Murialdo 1, 00146 Rome (Italy); Delitala, M.C. [Dipartimento di Scienze Geologiche, Universita ' Roma Tre' , Largo San Leonardo Murialdo 1, 00146 Rome (Italy); Primavera, P. [Dipartimento di Scienze Geologiche, Universita ' Roma Tre' , Largo San Leonardo Murialdo 1, 00146 Rome (Italy)

    2005-10-15

    The groundwater contribution into Green Lake and Black Lake (Vescovo Lakes Group), two cover collapse sinkholes in Pontina Plain (Central Italy), was estimated using water chemistry and a {sup 222}Rn budget. These data can constrain the interactions between sinkholes and deep seated fluid circulation, with a special focus on the possibility of the bedrock karst aquifer feeding the lake. The Rn budget accounted for all quantifiable surface and subsurface input and output fluxes including the flux across the sediment-water interface. The total value of groundwater discharge into Green Lake and Black Lake ({approx}540 {+-} 160 L s{sup -1}) obtained from the Rn budget is lower than, but comparable with historical data on the springs group discharge estimated in the same period of the year (800 {+-} 90 L s{sup -1}). Besides being an indirect test for the reliability of the Rn-budget 'tool', it confirms that both Green and Black Lake are effectively springs and not simply 'water filled' sinkholes. New data on the water chemistry and the groundwater fluxes into the sinkhole area of Vescovo Lakes allows the assessment of the mechanism responsible for sinkhole formation in Pontina Plain and suggests the necessity of monitoring the changes of physical and chemical parameters of groundwater below the plain in order to mitigate the associated risk.

  6. Reactive nitrogen chemistry in aerosol water as a source of sulfate during haze events in China

    Science.gov (United States)

    Cheng, Yafang; Zheng, Guangjie; Wei, Chao; Mu, Qing; Zheng, Bo; Wang, Zhibin; Gao, Meng; Zhang, Qiang; Wang, Kebin; Carmichael, Gregory; Pöschl, Ulrich; Su, Hang

    2017-04-01

    Fine-particle pollution associated with winter haze threatens the health of more than 400 million people in the North China Plain. Sulfate is a major component of fine haze particles. Record sulfate concentrations of up to 300 μg m-3 were observed during the January 2013 winter haze event in Beijing. State-of-the-art air quality models that rely on sulfate production mechanisms requiring photochemical oxidants cannot predict these high levels because of the weak photochemistry activity during haze events. We find that the missing source of sulfate and particulate matter can be explained by reactive nitrogen chemistry in aerosol water. The aerosol water serves as a reactor, where the alkaline aerosol components trap SO2, which is oxidized by NO2 to form sulfate, whereby high reaction rates are sustained by the high neutralizing capacity of the atmosphere in northern China. This mechanism is self-amplifying because higher aerosol mass concentration corresponds to higher aerosol water content, leading to faster sulfate production and more severe haze pollution. Reference: Cheng, Y., Zheng, G., Wei, C., Mu, Q., Zheng, B., Wang, Z., Gao, M., Zhang, Q., He, K., Carmichael, G., Pöschl, U., and Su, H.: Reactive nitrogen chemistry in aerosol water as a source of sulfate during haze events in China, Science Advances, 2, 10.1126/sciadv.1601530, 2016.

  7. Assessing Changes in Water Chemistry Along the Mountain to Urban Gradient

    Science.gov (United States)

    Gabor, R. S.; Brooks, P. D.; Neilson, B. T.; Barnes, M. L.; Stout, T.; Millington, M. R.; Gelderloos, A.; Tennant, H.; Eiriksson, D.

    2015-12-01

    Throughout the western US, growing population centers rely on mountain watersheds that are already sensitive to hydrologic stressors. We examined rivers along Utah's Wasatch Front over a range of spatial and discharge scales, confusing on the mountain-to-urban transition to identify how urbanization impacts water resources. The rivers we studied all originate in canyons with impact level ranging from minimal human disturbance to roads and open grazing cattle. Each river enters an urban area after leaving the canyon, where there is significantly more anthropogenic impact on the system. As part of an interdisciplinary effort with the iUTAH project, sample sites were selected at intervals along each river and a variety of measurements were made, including basic water chemistry along with discharge, water isotopes, nutrients, and organic matter analysis. By combining physical and chemical parameters we were able to quantify groundwater influence in gaining reaches and how those differ between the mountain and urban environments. We also identified how the urban system impacted hydrologic and biogeochemical processes in the catchment. For example, in Red Butte Creek discharge tripled through gaining reached in the canyon with only small corresponding changes in conductivity or nitrate levels. However in the urban stretch a gaining reach that tripled the discharge corresponded with a doubling in the conductivity and order of magnitude increase in nitrate. The fact that we first see this change in chemistry during a gaining reach, and not in an area full of storm culverts, suggests that urban impact to stream chemistry predominately occurs through the groundwater. Further work will incorporate ecological and climatic data along with the hydrologic and chemical datasets to identify how controls on water resources change along the mountain to urban gradient. By combining this physical information with sociological data we can identify green infrastructure solutions to

  8. OT2_lkrist01_3: Disentangling the water chemistry of the spectacular outflow BHR71

    Science.gov (United States)

    Kristensen, L.

    2011-09-01

    At the earliest stages of low-mass star formation, observations show that mass accretion is associated with mass ejection in the form of collimated jets and bipolar outflows. The ejection activity can be traced as shocked regions, where shock waves originating from the central young stellar object (YSO) impact, and process the ambient interstellar medium (ISM) from which the star forms. This interaction generates molecular emission that is typical of the physical (temperature, density) and chemical (abundances) structure of the gas. Studying this molecular emission is the best way to understand the physical and chemical processes operating in shock regions. We propose to follow the water chemistry through one of the most spectacular and best-studied outflows in the Southern sky, BHR71. Because the water abundance is very susceptible to energetic input (both through direct formation in the gas-phase and through release from ice-coated dust grains), it is one of the best shock tracers. To trace the water chemistry accurately, velocity-resolved observations are required to disentangle different excitation regimes. Early Herschel results show that water excitation conditions resemble those of rotationally excited H2, i.e., high densities and temperatures of 300-1000 K. Currently, it is not possible to velocity-resolve rotational H2 lines. Herschel-HIFI has revealed that the water line profiles observed to date are very complex, and they look nothing like the spectra of other molecular traces. Water is therefore a unique tracer of the bulk of the shocked gas where the temperature is 300-1000 K. Given the importance of BHR71 as the most chemically rich outflow in the southern sky, that makes it a key benchmark for outflow and shock modelling with ALMA, we propose to map this outflow in a few key H2O lines with HIFI. The maps will provide legacy-value information on water and shock excitation as a function of position and velocity throughout the outflow.

  9. Impacts of drainage water discharge on the water chemistry of Lake Edku

    OpenAIRE

    Shakweer, L.

    2006-01-01

    Lake Edku which is considered as important fishing area in Egypt receives its water from two sources. The main source is the drainage water of Kom Belag and Bersik drains where it is annually supplied with 1836.55 × 106 m3 of water. The sea water of Abu Qir Bay enters the lake sometimes through the lake sea connection as subsurface water current under the action of wind specially in winter. The present study pointed out that the water temperature of the lake (22.38oC) was slightly higher than...

  10. Vertical gradients in water chemistry and age in the Northern High Plains Aquifer, Nebraska, 2003

    Science.gov (United States)

    McMahon, P.B.; Böhlke, J.K.; Carney, C.P.

    2007-01-01

    The northern High Plains aquifer is the primary source of water used for domestic, industrial, and irrigation purposes in parts of Colorado, Kansas, Nebraska, South Dakota, and Wyoming. Despite the aquifer’s importance to the regional economy, fundamental ground-water characteristics, such as vertical gradients in water chemistry and age, remain poorly defined. As part of the U.S. Geological Survey’s National Water-Quality Assessment Program, water samples from nested, short-screen monitoring wells installed in the northern High Plains aquifer were analyzed for major ions, nutrients, trace elements, dissolved organic carbon, pesticides, stable and radioactive isotopes, dissolved gases, and other parameters to evaluate vertical gradients in water chemistry and age in the aquifer. Chemical data and tritium and radiocarbon ages show that water in the aquifer was chemically and temporally stratified in the study area, with a relatively thin zone of recently recharged water (less than 50 years) near the water table overlying a thicker zone of older water (1,800 to 15,600 radiocarbon years). In areas where irrigated agriculture was an important land use, the recently recharged ground water was characterized by elevated concentrations of major ions and nitrate and the detection of pesticide compounds. Below the zone of agricultural influence, major-ion concentrations exhibited small increases with depth and distance along flow paths because of rock/water interactions. The concentration increases were accounted for primarily by dissolved calcium, sodium, bicarbonate, sulfate, and silica. In general, the chemistry of ground water throughout the aquifer was of high quality. None of the approximately 90 chemical constituents analyzed in each sample exceeded primary drinking-water standards.Mass-balance models indicate that changes in groundwater chemistry along flow paths in the aquifer can be accounted for by small amounts of feldspar and calcite dissolution; goethite

  11. Groundwater chemistry near an impoundment for produced water, Powder River Basin, Wyoming, USA

    Science.gov (United States)

    Healy, R.W.; Bartos, T.T.; Rice, C.A.; McKinley, M.P.; Smith, B.D.

    2011-01-01

    The Powder River Basin is one of the largest producers of coal-bed natural gas (CBNG) in the United States. An important environmental concern in the Basin is the fate of the large amounts of groundwater extracted during CBNG production. Most of this produced water is disposed of in unlined surface impoundments. A 6-year study of groundwater flow and water chemistry at one impoundment, Skewed Reservoir, has produced the most detailed data set for any impoundment in the Basin. Data were collected from a network of 21 observation wells and three suction lysimeters. A groundwater mound formed atop bedrock within initially unsaturated, unconsolidated deposits underlying the reservoir. Heterogeneity in physical and chemical properties of sediments resulted in complex groundwater flow paths and highly variable groundwater chemistry. Sulfate, bicarbonate, sodium, and magnesium were the dominant ions in all areas, but substantial variability existed in relative concentrations; pH varied from less than 3 to more than 9, and total dissolved solids concentrations ranged from less than 5000 to greater than 100,000 mg/L. Selenium was a useful tracer of reservoir water; selenium concentrations exceeded 300 μg/L in samples obtained from 18 of the 24 sampling points. Groundwater travel time from the reservoir to a nearby alluvial aquifer (a linear distance of 177 m) was calculated at 474 days on the basis of selenium concentrations. The produced water is not the primary source of solutes in the groundwater. Naturally occurring salts and minerals within the unsaturated zone, dissolved and mobilized by infiltrating impoundment water, account for most of the solute mass in groundwater. Gypsum dissolution, cation-exchange, and pyrite oxidation appear to be important reactions. The complex geochemistry and groundwater flow paths at the study site underscore the difficulty in assessing effects of surface impoundments on water resources within the Powder River Basin.

  12. Potential linkage between sediment oxygen demand and pore water chemistry in weir-impounded rivers.

    Science.gov (United States)

    Lee, Mi-Hee; Jung, Heon-Jae; Kim, Sung-Han; An, Sung-Uk; Choi, Jung Hyun; Lee, Hyo-Jin; Huh, In-Ae; Hur, Jin

    2017-10-18

    Due to recent weir construction on four major rivers in South Korea, sediment has accumulated in the river bottom near the weirs, which has in turn raised concerns over the quality of overlying water. In this study, the seasonal and spatial variations of sediment oxygen demand (SOD) and the influencing factors were explored using pore water chemistry for the weir-impounded rivers. Muddy and sandy sediment samples were taken from 24 different sites along the four major rivers in summer and autumn, 2016. The SOD was measured in a laboratory based on 10-hour incubation at in situ temperature. The measured pore water chemistry included the concentrations of dissolved organic carbon (DOC), total dissolved nitrogen (TDN), inorganic nitrogen (NH3-N, NO3-N, NO2-N), and phosphate phosphorous (PO4-P), and the optical properties from UV absorption spectra and fluorescence excitation-emission matrixes coupled with parallel factor analysis (EEM-PARAFAC). Significant differences in SOD values between muddy and sandy sediments were found only in summer (p=0.047). The higher SOD in summer versus autumn (p=0.015) was attributed to seasonal temperature differences. The higher NH3-N and the lower NO3-N of the pore water samples in summer versus autumn suggested that organic nitrogen decomposition via an ammonification and nitrification process could operate as an important factor for the SOD variations in summer and autumn, respectively. Principal component analysis revealed the mutual contributions of nitrogen-associated processes and the organic composition in pore water to increasing SOD levels. NH3-N in sediment pore water alone could be a good predictor for SOD. However, multiple regression analysis using NH3-N, fluorescence index and terrestrial humic-like components improved the estimation capability for SOD variations. Copyright © 2017. Published by Elsevier B.V.

  13. Surface chemistry and corrosion behavior of Inconel 625 and 718 in subcritical, supercritical, and ultrasupercritical water

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez, David; Merwin, Augustus; Karmiol, Zachary; Chidambaram, Dev, E-mail: dcc@unr.edu

    2017-05-15

    Highlights: • Mixtures of oxides containing Ni, Fe, Cr and Nb formed on the surface. • Short term exposure tests observed breakdown of native film. • Formation of a Fe rich oxide layer on Inconel 718 prevents mass loss. - Abstract: Corrosion behavior of Inconel 625 and 718 in subcritical, supercritical and ultrasupercritical water was studied as a function of temperature and time. The change in the chemistry of the as-received surface film on Inconel 625 and 718 after exposure to subcritical water at 325 °C and supercritical water at 425 °C and 527.5 °C for 2 h was studied. After exposure to 325 °C subcritical water, the CrO{sub 4}{sup 2−} based film formed; however minor quantities of NiFe{sub x}Cr{sub 2-x}O{sub 4} spinel compounds were observed. The oxide film formed on both alloys when exposed to supercritical water at 425 °C consisted of NiFe{sub x}Cr{sub 2-x}O{sub 4} spinel. The surface films on both alloys were identified as NiFe{sub 2}O{sub 4} when exposed to supercritical water at 527.5 °C. To characterize the fully developed oxide layer, studies were conducted at test solution temperatures of 527.5 and 600 °C. Samples were exposed to these temperatures for 24, 96, and 200 h. Surface chemistry was analyzed using X-ray diffraction, as well as Raman and X-ray photoelectron spectroscopies. Inconel 718 exhibited greater mass gain than Inconel 625 for all temperatures and exposure times. The differences in corrosion behavior of the two alloys are attributed to the lower content of chromium and increased iron content of Inconel 718 as compared to Inconel 625.

  14. Surface chemistry and corrosion behavior of Inconel 625 and 718 in subcritical, supercritical, and ultrasupercritical water

    Science.gov (United States)

    Rodriguez, David; Merwin, Augustus; Karmiol, Zachary; Chidambaram, Dev

    2017-05-01

    Corrosion behavior of Inconel 625 and 718 in subcritical, supercritical and ultrasupercritical water was studied as a function of temperature and time. The change in the chemistry of the as-received surface film on Inconel 625 and 718 after exposure to subcritical water at 325 °C and supercritical water at 425 °C and 527.5 °C for 2 h was studied. After exposure to 325 °C subcritical water, the CrO42- based film formed; however minor quantities of NiFexCr2-xO4 spinel compounds were observed. The oxide film formed on both alloys when exposed to supercritical water at 425 °C consisted of NiFexCr2-xO4 spinel. The surface films on both alloys were identified as NiFe2O4 when exposed to supercritical water at 527.5 °C. To characterize the fully developed oxide layer, studies were conducted at test solution temperatures of 527.5 and 600 °C. Samples were exposed to these temperatures for 24, 96, and 200 h. Surface chemistry was analyzed using X-ray diffraction, as well as Raman and X-ray photoelectron spectroscopies. Inconel 718 exhibited greater mass gain than Inconel 625 for all temperatures and exposure times. The differences in corrosion behavior of the two alloys are attributed to the lower content of chromium and increased iron content of Inconel 718 as compared to Inconel 625.

  15. Seasonal variability of natural water chemistry affects the fate and behaviour of silver nanoparticles.

    Science.gov (United States)

    Ellis, Laura-Jayne A; Baalousha, Mohammed; Valsami-Jones, Eugenia; Lead, Jamie R

    2017-10-23

    Understanding the environmental behaviour of nanoparticles (NPs) after release into aquatic systems is essential to predict the environmental implications of nanotechnology. Silver nanoparticles (AgNPs) represent a major class of engineered NPs with a significant potential for environmental impact. Therefore, investigating their transformations in natural waters will help predict their long term environmental fate and behaviour. AgNPs were characterized in natural lake water collected seasonally from the same freshwater source, using column microcosms to assess their behaviour and transport at different depths. Building on our previous work using similar systems with synthetic waters, the influence of water chemistry and NP surface modifications on colloidal stability and dissolution in natural lake water over time was investigated. A simple sedimentation-diffusion model parameterized by the particle properties and total Ag concentration was successfully used to understand AgNPs transport behaviour. PVP coated AgNPs remained colloidally stable, with their transport in the water column dominated by diffusion, and exhibited no significant or substantial changes in data or model parameters for different seasons. Citrate coated AgNPs were susceptible to rapid aggregation, sedimentation, dissolution and reprecipitation; their transport in the water column was determined by both diffusion and sedimentation. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.

  16. Does water chemistry limit the distribution of New Zealand mud snails in Redwood National Park?

    Science.gov (United States)

    Vazquez, Ryan; Ward, Darren M.; Sepulveda, Adam

    2016-01-01

    New Zealand mud snails (NZMS) are exotic mollusks present in many waterways of the western United States. In 2009, NZMS were detected in Redwood Creek in Redwood National Park, CA. Although NZMS are noted for their ability to rapidly increase in abundance and colonize new areas, after more than 5 years in Redwood Creek, their distribution remains limited to a ca. 300 m reach. Recent literature suggests that low specific conductivity and environmental calcium can limit NZMS distribution. We conducted laboratory experiments, exposing NZMS collected from Redwood Creek to both natural waters and artificial treatment solutions, to determine if low conductivity and calcium concentration limit the distribution of NZMS in Redwood National Park. For natural water exposures, we held NZMS in water from their source location (conductivity 135 μS/cm, calcium 13 mg/L) or water from four other locations in the Redwood Creek watershed encompassing a range of conductivity (77–158 μS/cm) and calcium concentration (4 months) in the lowest conductivity waters from Redwood Creek and all but the lowest-conductivity treatment solutions, regardless of calcium concentration. However, reproductive output was very low in all natural waters and all low-calcium treatment solutions. Our results suggest that water chemistry may inhibit the spread of NZMS in Redwood National Park by reducing their reproductive output.

  17. Temporal variations of geyser water chemistry in the Upper Geyser Basin, Yellowstone National Park, USA

    Science.gov (United States)

    Hurwitz, Shaul; Hunt, Andrew G.; Evans, William C.

    2012-01-01

    Geysers are rare features that reflect a delicate balance between an abundant supply of water and heat and a unique geometry of fractures and porous rocks. Between April 2007 and September 2008, we sampled Old Faithful, Daisy, Grand, Oblong, and Aurum geysers in Yellowstone National Park's Upper Geyser Basin and characterized temporal variations in major element chemistry and water isotopes (δ18O, δD, 3H). We compare these temporal variations with temporal trends of Geyser Eruption Intervals (GEI). SiO2 concentrations and geothermometry indicate that the geysers are fed by waters ascending from a reservoir with temperatures of ∼190 to 210°C. The studied geysers display small and complex chemical and isotopic seasonal variations, and geysers with smaller volume display larger seasonal variations than geysers with larger volumes. Aurum and Oblong Geysers contain detectable tritium concentrations, suggesting that erupted water contains some modern meteoric water. We propose that seasonal GEI variations result from varying degrees of evaporation, meteoric water recharge, water table fluctuations, and possible hydraulic interaction with the adjacent Firehole River. We demonstrate that the concentrations of major dissolved species in Old Faithful Geyser have remained nearly constant since 1884 despite large changes in Old Faithful's eruption intervals, suggesting that no major changes have occurred in the hydrothermal system of the Upper Geyser Basin for >120 years. Our data set provides a baseline for monitoring future changes in geyser activity that might result from varying climate, earthquakes, and changes in heat flow from the underlying magmatic system.

  18. Effects of flow and water chemistry on lead release rates from pipe scales.

    Science.gov (United States)

    Xie, Yanjiao; Giammar, Daniel E

    2011-12-01

    Lead release from pipe scales was investigated under different water compositions, stagnation times, and flow regimes. Pipe scales containing PbO(2) and hydrocerussite (Pb(3)(OH)(2)(CO(3))(2)) were developed on lead pipes by conditioning the pipes with water containing free chlorine for eight months. Water chemistry and the composition of the pipe scales are two key factors affecting lead release from pipe scales. The water rarely reached equilibrium with pipe scales within one day, which makes solid-water contact time and corrosion product dissolution rates the controlling factors of lead concentrations for the conditions tested. Among five water compositions studied, a solution with orthophosphate had the lowest dissolved lead release rate and highest particulate lead release rate. Free chlorine also decreased the dissolved lead release rate at stagnant conditions. Water flow increased rates of release of both dissolved and particulate lead by accelerating the mass transfer of lead out of the porous pipe scales and by physically destabilizing pipe scales. Dissolved lead comprised the majority of the lead released at both stagnant and laminar flow conditions. Copyright © 2011 Elsevier Ltd. All rights reserved.

  19. Glycol-Water Interactions and co-existing phases and Temperature Dependent Solubility. An Example Of Carbon-Hydrogen Chemistry In Water

    CERN Document Server

    Michael, Fredrick

    2010-01-01

    Recently there has been great interest in Glycol-Water chemistry and solubility and temperature dependent phase dynamics. The Glycol-Water biochemistry of interactions is present in plant biology and chemistry, is of great interest to chemical engineers and biochemists as it is a paradigm of Carbon-Hydrogen Water organic chemistry. There is an interest moreover in formulating a simpler theory and computation model for the Glycol-Water interaction and phase dynamics, that is not fully quantum mechanical yet has the high accuracy available from a fully quantum mechanical theory of phase transitions of fluids and Fermi systems. Along these lines of research interest we have derived a Lennard-Jones -like theory of interacting molecules-Water in a dissolved adducts of Glycol-Water system interacting by Hydrogen bonds whose validity is supported at the scale of interactions by other independent molecular dynamics investigations that utilize force fields dependent on their experimental fittings to the Lennard-Jones ...

  20. Cumulative soil chemistry changes from land application of saline-sodic waters

    Energy Technology Data Exchange (ETDEWEB)

    Ganjegunte, G.K.; King, L.A.; Vance, G.F. [University of Wyoming, Laramie, WY (United States). Department for Renewable Resources

    2008-09-15

    Management of large volumes (60,000 ha-m) of co-production water associated with coal bed natural gas (CBNG) water extraction is a potential concern in the Powder River Basin (PRB) of Wyoming and Montana due to elevated water salinity and sodicity levels. Land application of saline-sodic CBNG water is a common water management method being practiced in the PRB, which can result in deterioration in soil quality. The objective of this study was to evaluate effects from 1 to 4 yr of land application with CBNG water on soil chemical properties at six study sites (fine to loamy, mixed to smectitic, mesic, Ustic Ardisols and Entisols) in the Wyoming PRB region. Changes in chemistry of soils collected from six depths irrigated with CBNG water were compared with representative non-irrigated soils. Applications of CBNG water significantly increased soil EC, SAR, and ESP values (up to 21, 74, and 24 times, respectively) compared with non-irrigated soils. Differences in soil chemical properties between an irrigated and non-irrigated coarse-textured soil were less than that of fine-textured soils, emphasizing texture as an important factor for salinity buildup. Pretreatment of CBNG water using a sulfur burner and application of gypsum and elemental S soil amendments reduced soil pH but did not prevent the build-up of salts and sodium. Study results suggest that current CBNG water management strategies are not as effective as projected. Additional research is needed to develop management strategies appropriate for mitigating adverse effects of CBNG water irrigation.

  1. Cumulative soil chemistry changes from land application of saline-sodic waters.

    Science.gov (United States)

    Ganjegunte, Girisha K; King, Lyle A; Vance, George F

    2008-01-01

    Management of large volumes (60,000 ha-m) of co-production water associated with coal bed natural gas (CBNG) water extraction is a potential concern in the Powder River Basin (PRB) of Wyoming and Montana due to elevated water salinity and sodicity levels. Land application of saline-sodic CBNG water is a common water management method being practiced in the PRB, which can result in deterioration in soil quality. The objective of this study was to evaluate effects from 1 to 4 yr of land application with CBNG water on soil chemical properties at six study sites (fine to loamy, mixed to smectitic, mesic, Ustic Ardisols and Entisols) in the Wyoming PRB region. Changes in chemistry of soils collected from six depths irrigated with CBNG water were compared with representative nonirrigated soils. Applications of CBNG water significantly increased soil EC, SAR, and ESP values (up to 21, 74, and 24 times, respectively) compared with nonirrigated soils. Differences in soil chemical properties between an irrigated and nonirrigated coarse-textured soil were less than that of fine-textured soils, emphasizing texture as an important factor for salinity buildup. Pretreatment of CBNG water using a sulfur burner and application of gypsum and elemental S soil amendments reduced soil pH but did not prevent the build-up of salts and sodium. Study results suggest that current CBNG water management strategies are not as effective as projected. Additional research is needed to develop management strategies appropriate for mitigating adverse effects of CBNG water irrigation.

  2. Evaluating the effects of variable water chemistry on bacterial transport during infiltration

    Science.gov (United States)

    Zhang, Haibo; Nordin, Nahjan Amer; Olson, Mira S.

    2013-07-01

    Bacterial infiltration through the subsurface has been studied experimentally under different conditions of interest and is dependent on a variety of physical, chemical and biological factors. However, most bacterial transport studies fail to adequately represent the complex processes occurring in natural systems. Bacteria are frequently detected in stormwater runoff, and may present risk of microbial contamination during stormwater recharge into groundwater. Mixing of stormwater runoff with groundwater during infiltration results in changes in local solution chemistry, which may lead to changes in both bacterial and collector surface properties and subsequent bacterial attachment rates. This study focuses on quantifying changes in bacterial transport behavior under variable solution chemistry, and on comparing the influences of chemical variability and physical variability on bacterial attachment rates. Bacterial attachment rate at the soil-water interface was predicted analytically using a combined rate equation, which varies temporally and spatially with respect to changes in solution chemistry. Two-phase Monte Carlo analysis was conducted and an overall input-output correlation coefficient was calculated to quantitatively describe the importance of physiochemical variation on the estimates of attachment rate. Among physical variables, soil particle size has the highest correlation coefficient, followed by porosity of the soil media, bacterial size and flow velocity. Among chemical variables, ionic strength has the highest correlation coefficient. A semi-reactive microbial transport model was developed within HP1 (HYDRUS1D-PHREEQC) and applied to column transport experiments with constant and variable solution chemistries. Bacterial attachment rates varied from 9.10 × 10- 3 min- 1 to 3.71 × 10- 3 min- 1 due to mixing of synthetic stormwater (SSW) with artificial groundwater (AGW), while bacterial attachment remained constant at 9.10 × 10- 3 min- 1 in a

  3. Source Water Flow Pathways In Forested, Mountain, Headwater Streams: A Link Between Sediment Movement Patterns And Stream Water Chemistry.

    Science.gov (United States)

    Martin, S.; Conklin, M. H.; Liu, F.

    2015-12-01

    Three years of continuous and discrete sediment and water quality data, from four forested, mountain, headwater catchments in the Sierra Nevada, is used to identify water sources, determine the importance of sub-surface flow pathways, detect any changes in source waters due to seasonal variation or drought, and link flow pathways with observed patterns of in-channel sediment movement within the study watersheds. Patterns in stream chemistry and turbidity point to infiltration as the dominant flow pathway within these catchments. Data support a flow pathway conceptual model in which precipitation water infiltrates into the shallow or deeper subsurface, increasing the hydraulic head of the water table and pushing pre-event water into the stream ahead of event water. Study catchments contain perennial streams and are characterized by a Mediterranean climate with a distinct wet and dry season. Sites are located in the rain-snow transition zone with snow making up 40 to 60 percent of average annual precipitation. Barring human disturbances such as logging/grazing (compaction) or fire (hydrophobicity), catchment soils have high infiltration capacities. Springs and seeps maintain baseflow during the summer low-flow season, and shifting chemical signals within the streams indicate the increased importance of sub-surface water sources during drought years. End-member mixing analysis was conducted to identify possible water end members. Turbidity hysteresis patterns described by previous studies show in-channel sources are dominant for discharge events year round, and there is no difference in fine sediment delivery to streams with or without a soil protecting layer of snow on the land surface. The dominance of sub-surface water sources and evidence for infiltration flow fits with turbidity data, as little material is reaching the stream due to erosive overland flow. An understanding of flow pathways provides a foundation for sustainable land use management in forested

  4. Surveillance for waterborne disease and outbreaks associated with drinking water and water not intended for drinking--United States, 2005-2006.

    Science.gov (United States)

    Yoder, Jonathan; Roberts, Virginia; Craun, Gunther F; Hill, Vincent; Hicks, Lauri A; Alexander, Nicole T; Radke, Vince; Calderon, Rebecca L; Hlavsa, Michele C; Beach, Michael J; Roy, Sharon L

    2008-09-12

    Since 1971, CDC, the U.S. Environmental Protection Agency (EPA), and the Council of State and Territorial Epidemiologists have maintained a collaborative Waterborne Disease and Outbreak Surveillance System (WBDOSS) for collecting and reporting data related to occurrences and causes of waterborne-disease outbreaks (WBDOs) and cases of waterborne disease. This surveillance system is the primary source of data concerning the scope and effects of waterborne disease in the United States. Data presented summarize 28 WBDOs that occurred during January 2005--December 2006 and four previously unreported WBDOs that occurred during 1979--2002. The surveillance system includes data on WBDOs associated with recreational water, drinking water, water not intended for drinking (WNID) (excluding recreational water), and water use of unknown intent. Public health departments in the states, territories, localities, and Freely Associated States (FAS) (i.e., the Republic of the Marshall Islands, the Federated States of Micronesia, and the Republic of Palau, formerly parts of the U.S.-administered Trust Territory of the Pacific Islands) are primarily responsible for detecting and investigating WBDOs and voluntarily reporting them to CDC by a standard form. Only cases and outbreaks associated with drinking water, WNID (excluding recreational water), and water of unknown intent (WUI) are summarized in this report. Cases and outbreaks associated with recreational water are reported in a separate Surveillance Summary. Fourteen states reported 28 WBDOs that occurred during 2005--2006: a total of 20 were associated with drinking water, six were associated with WNID, and two were associated with WUI. The 20 drinking water-associated WBDOs caused illness among an estimated 612 persons and were linked to four deaths. Etiologic agents were identified in 18 (90.0%) of the drinking water-associated WBDOs. Among the 18 WBDOs with identified pathogens, 12 (66.7%) were associated with bacteria, three

  5. Relationships between water and gas chemistry in mature coalbed methane reservoirs of the Black Warrior Basin

    Science.gov (United States)

    Pashin, Jack C.; McIntyre-Redden, Marcella R.; Mann, Steven D.; Kopaska-Merkel, David C.; Varonka, Matthew S.; Orem, William H.

    2014-01-01

    Water and gas chemistry in coalbed methane reservoirs of the Black Warrior Basin reflects a complex interplay among burial processes, basin hydrodynamics, thermogenesis, and late-stage microbial methanogenesis. These factors are all important considerations for developing production and water management strategies. Produced water ranges from nearly potable sodium-bicarbonate water to hypersaline sodium-chloride brine. The hydrodynamic framework of the basin is dominated by structurally controlled fresh-water plumes that formed by meteoric recharge along the southeastern margin of the basin. The produced water contains significant quantities of hydrocarbons and nitrogen compounds, and the produced gas appears to be of mixed thermogenic-biogenic origin.Late-stage microbial methanogenesis began following unroofing of the basin, and stable isotopes in the produced gas and in mineral cements indicate that late-stage methanogenesis occurred along a CO2-reduction metabolic pathway. Hydrocarbons, as well as small amounts of nitrate in the formation water, probably helped nourish the microbial consortia, which were apparently active in fresh to hypersaline water. The produced water contains NH4+ and NH3, which correlate strongly with brine concentration and are interpreted to be derived from silicate minerals. Denitrification reactions may have generated some N2, which is the only major impurity in the coalbed gas. Carbon dioxide is a minor component of the produced gas, but significant quantities are dissolved in the formation water. Degradation of organic compounds, augmented by deionization of NH4+, may have been the principal sources of hydrogen facilitating late-stage CO2 reduction.

  6. Reticular Chemistry in Action: A Hydrolytically Stable MOF Capturing Twice Its Weight in Adsorbed Water

    KAUST Repository

    Towsif Abtab, Sk Md

    2018-01-11

    Summary Hydrolytically stable adsorbents, with notable water uptake, are of prime importance and offer great potential for many water-adsorption-related applications. Nevertheless, deliberate construction of tunable porous solids with high porosity and high stability remains challenging. Here, we present the successful deployment of reticular chemistry to address this demand: we constructed Cr-soc-MOF-1, a chemically and hydrolytically stable chromium-based metal-organic framework (MOF) with underlying soc topology. Prominently, Cr-soc-MOF-1 offers the requisite thermal and chemical stability concomitant with unique adsorption properties, namely extraordinary high porosity (apparent surface area of 4,549 m2/g) affording a water vapor uptake of 1.95 g/g at 70% relative humidity. This exceptional water uptake is maintained over more than 100 adsorption-desorption cycles. Markedly, the adsorbed water can be fully desorbed by just the simple reduction of the relative humidity at 25°C. Cr-soc-MOF-1 offers great potential for use in applications pertaining to water vapor control in enclosed and confined spaces and dehumidification.

  7. Nitrate Reduction in an Unconfined Sandy Aquifer: Water Chemistry, Reduction Processes, and Geochemical Modeling

    Science.gov (United States)

    Postma, Dieke; Boesen, Carsten; Kristiansen, Henning; Larsen, Flemming

    1991-08-01

    Nitrate distribution and reduction processes were investigated in an unconfined sandy aquifer of Quaternary age. Ground water chemistry was studied in a series of eight multilevel samplers along a flow line, deriving water from both arable and forested land. Results show that plumes of nitrate-contaminated groundwater emanate from the agricultural areas and spread through the aquifer. The aquifer can be subdivided into an upper 10- to 15-m thick oxic zone that contains O2 and NO3-, and a lower anoxic zone characterized by Fe2+-rich waters. The redox boundary is very sharp, which suggests that reduction processes of O2 and NO3- occur at rates that are fast compared to the rate of downward water transport. Nitrate-contaminated groundwater contains total contents of dissolved ions that are two to four times higher than in groundwater derived from the forested area. The persistence of the high content of total dissolved ions in the NO3--free anoxic zone indicates the downward migration of contaminants and that active nitrate reduction is taking place. Nitrate is apparently reduced to N2 because both nitrite and ammonia are absent or found at very low concentrations. Possible electron donors in the reduced zone of the aquifer are organic matter, present as reworked brown coal fragments from the underlying Miocene, and small amounts of pyrite at an average concentration of 3.6 mmol/kg. Electron balances across the redoxcline, based on concentrations of O2, NO3-, SO42- and total inorganic carbon (TIC), indicate that pyrite is by far the dominant electron donor even though organic matter is much more abundant. Groundwater transport and chemical reactions were modeled using the code PHREEQM, which combines a chemical equilibrium model with a one-dimensional mixing cell transport model. Only the vertical component of the water transport was modeled since, in contrast to rates along flow lines, the vertical rates are close to constant as required by the one-dimensional model

  8. Microbiology of broiler carcasses and chemistry of chiller water as affected by water reuse.

    Science.gov (United States)

    Northcutt, J K; Smith, D; Huezo, R I; Ingram, K D

    2008-07-01

    A study was conducted to determine the effects of treating and reusing poultry chiller water in a commercial poultry processing facility. Broiler carcasses and chiller water were obtained from a commercial processing facility which had recently installed a TOMCO Pathogen Management System to recycle water in sections 2 and 3 of two 3-compartment chillers. In this system, reused water is blended with fresh water to maintain the chiller volume. Carcasses were sampled prechill and postchill (final exit), and chiller water was sampled from the beginning and end of each of the 3 sections. Carcasses were subjected to a whole carcass rinse (WCR) in 0.1% peptone. Numbers of Escherichia coli (EC), coliforms (CF), and Campylobacter (CPY) were determined from the WCR and chiller water samples. Prevalence of Salmonella (SAL) was also determined on the WCR and chiller water samples. On average, prechill levels of bacteria recovered from rinses were 2.6, 2.9, and 2.6 log10 cfu/mL for EC, CF, and CPY, respectively. Ten out of 40 (25%) prechill carcasses were positive for SAL. After chilling, numbers of EC, CF, and CPY recovered from carcass rinses decreased by 1.5, 1.5, and 2.0 log10 cfu/mL, respectively. However, 9 out of 40 (22%) postchill carcasses were positive for SAL. When the chiller water samples were tested, counts of EC, CF, and CPY were found only in water collected from the first section of the chiller (inlet and outlet). Two of 4 water samples collected from the inlet of the first section tested positive for SAL. This study shows that fresh and reused water can be used to cool poultry in chiller systems to achieve a reduction in numbers of bacteria (EC, CF, and CPY) or equivalent prevalence (SAL) of bacteria recovered from broiler carcasses.

  9. A study of water chemistry extends the benefits of using silica-based nanoparticles on enhanced oil recovery

    Science.gov (United States)

    Hendraningrat, Luky; Torsæter, Ole

    2016-01-01

    Chemistry of the injected water has been investigated as an important parameter to improve/enhance oil recovery (IOR/EOR). Numerous extensive experiments have observed that water chemistry, such as ionic composition and salinity, can be modified for IOR/EOR purposes. However, the possible oil displacement mechanism remains debatable. Nanoparticle recently becomes more popular that have shown a great potential for IOR/EOR purposes in lab-scale, where in most experiments, water-based fluid were used as dispersed fluid. As yet, there has been no discussion in the literature on the study of water chemistry on enhanced oil recovery using silica-based nanoparticles. A broad range of laboratory studies involving rock, nanoparticles and fluid characterization; fluid-fluid and fluid-rock interactions; surface conductivity measurement; coreflood experiment; injection strategy formulation; filtration mechanism and contact angle measurement are conducted to investigate the impact of water chemistry, such as water salinity and ionic composition including hardness cations, on the performance of silica-based nanoparticles in IOR/EOR process and reveal possible displacement mechanism. The experimental results demonstrated that water salinity and ionic composition significantly impacted oil recovery using hydrophilic silica-based nanoparticles and that the oil recovery increased with the salinity. The primary findings from this study are that the water salinity, the ionic composition and the injection strategy are important parameters to be considered in Nano-EOR.

  10. Water as Life, Death, and Power: Building an Integrated Interdisciplinary Course Combining Perspectives from Anthropology, Biology, and Chemistry

    Science.gov (United States)

    Willermet, Cathy; Mueller, Anja; Juris, Stephen J.; Drake, Eron; Upadhaya, Samik; Chhetri, Pratik

    2013-01-01

    In response to a request from a campus student organization, faculty from three fields came together to develop and teach an integrated interdisciplinary course on water issues and social activism. This course, "Water as Life, Death, and Power", brought together topics from the fields of anthropology, biology and chemistry to explore…

  11. Responses of soil and water chemistry to mountain pine beetle induced tree mortality in Grand County, Colorado, USA

    Science.gov (United States)

    David W. Clow; Charles C. Rhoades; Jennifer Briggs; Megan Caldwell; William M. Lewis

    2011-01-01

    Pine forest in northern Colorado and southern Wyoming, USA, are experiencing the most severe mountain pine beetle epidemic in recorded history, and possible degradation of drinking-water quality is a major concern. The objective of this study was to investigate possible changes in soil and water chemistry in Grand County, Colorado in response to the epidemic,...

  12. Impact of water chemistry on the particle-specific toxicity of copper nanoparticles to Daphnia magna.

    Science.gov (United States)

    Xiao, Yinlong; Peijnenburg, Willie J G M; Chen, Guangchao; Vijver, Martina G

    2018-01-01

    Toxicity of metallic nanoparticle suspensions (NP(total)) is generally assumed to result from the combined effect of the particles present in suspensions (NP(particle)) and their released ions (NP(ion)). Evaluation and consideration of how water chemistry affects the particle-specific toxicity of NP(total) are critical for environmental risk assessment of nanoparticles. In this study, it was found that the toxicity of Cu NP(particle) to Daphnia magna, in line with the trends in toxicity for Cu NP(ion), decreased with increasing pH and with increasing concentrations of divalent cations and dissolved organic carbon (DOC). Without the addition of DOC, the toxicity of Cu NP(total) to D. magna at the LC50 was driven mainly by Cu NP(ion) (accounting for ≥53% of the observed toxicity). However, toxicity of Cu NP(total) in the presence of DOC at a concentration ranging from 5 to 50mg C/L largely resulted from the NP(particle) (57%-85%), which could be attributable to the large reduction of the concentration of Cu NP(ion) and the enhancement of the stability of Cu NP(particle) when DOC was added. Our results indicate that water chemistry needs to be explicitly taken into consideration when evaluating the role of NP(particle) and NP(ion) in the observed toxicity of NP(total). Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Water chemistry and its effects on the physiology and survival of Atlantic salmon Salmo salar smolts

    Science.gov (United States)

    Liebich, T.; McCormick, S.D.; Kircheis, D.; Johnson, K.; Regal, R.; Hrabik, T.

    2011-01-01

    The physiological effects of episodic pH fluctuations on Atlantic salmon Salmo salar smolts in eastern Maine, U.S.A., were investigated. During this study, S. salar smolts were exposed to ambient stream-water chemistry conditions at nine sites in four catchments for 3 and 6 day intervals during the spring S. salar smolt migration period. Plasma chloride, plasma glucose, gill aluminium and gill Na+- and K+-ATPase levels in S. salar smolts were assessed in relation to ambient stream-water chemistry during this migration period. Changes in both plasma chloride and plasma glucose levels of S. salar smolts were strongly correlated with stream pH, and S. salar smolt mortality occurred in one study site with ambient stream pH between 5??6 and 5??8 during the study period. The findings from this study suggest that physiological effects on S. salar smolts are strongly correlated with stream pH and that in rivers and streams with low dissolved organic carbon (DOC) concentrations the threshold for physiological effects and mortality probably occurs at a higher pH and shorter exposure period than in rivers with higher DOC. Additionally, whenever an acidification event in which pH drops below 5??9 coincides with S. salar smolt migration in eastern Maine rivers, there is potential for a significant reduction in plasma ions of S. salar smolts. ?? 2011 The Fisheries Society of the British Isles.

  14. Trends in the chemistry of atmospheric deposition and surface waters in the Lake Maggiore catchment

    Directory of Open Access Journals (Sweden)

    M. Rogora

    2001-01-01

    Full Text Available The Lake Maggiore catchment is the area of Italy most affected by acid deposition. Trend analysis was performed on long-term (15-30 years series of chemical analyses of atmospheric deposition, four small rivers draining forested catchments and four high mountain lakes. An improvement in the quality of atmospheric deposition was detected, due to decreasing sulphate concentration and increasing pH. Similar trends were also found in high mountain lakes and in small rivers. Atmospheric deposition, however, is still providing a large and steady flux of nitrogen compounds (nitrate and ammonium which is causing increasing nitrogen saturation in forest ecosystems and increasing nitrate levels in rivers. Besides atmospheric deposition, an important factor controlling water acidification and recovery is the weathering of rocks and soils which may be influenced by climate warming. A further factor is the episodic deposition of Saharan calcareous dust which contributes significantly to base cation deposition. Keywords: trend, atmospheric deposition, nitrogen, stream water chemistry.

  15. Modeling water chemistry change and contaminant transport in riverbank filtration systems

    Science.gov (United States)

    Mustafa, Shaymaa; Bahar, Arifah; Aziz, Zainal Abdul; Suratman, Saim

    2016-06-01

    Riverbank filtration system is river water treatment approach based on natural removal of contaminants due to physical, chemical and biological processes. In this article, an analytical model is developed by using Green's function method to simulate the effects of pumping well and microbial activity that occurs in riverbed sediments on contaminant transport and evolution of water chemistry. The model is tested with data collected previously for RBF site in France. The results are compared with numerical simulation conducted in the literature by using finite difference method. Graphically, it is noticed that both numerical and analytical results have almost the same behavior. Also it is found that the model can simulate the decreasing of one pollutant concentration at the zone where the bacteria starts to consume this pollutant.

  16. Relationships of surface water, pore water, and sediment chemistry in wetlands adjacent to Great Salt Lake, Utah, and potential impacts on plant community health.

    Science.gov (United States)

    Carling, Gregory T; Richards, David C; Hoven, Heidi; Miller, Theron; Fernandez, Diego P; Rudd, Abigail; Pazmino, Eddy; Johnson, William P

    2013-01-15

    We collected surface water, pore water, and sediment samples at five impounded wetlands adjacent to Great Salt Lake, Utah, during 2010 and 2011 in order to characterize pond chemistry and to compare chemistry with plant community health metrics. We also collected pore water and sediment samples along multiple transects at two sheet flow wetlands during 2011 to investigate a potential link between wetland chemistry and encroachment of invasive emergent plant species. Samples were analyzed for a suite of trace and major elements, nutrients, and relevant field parameters. The extensive sampling campaign provides a broad assessment of Great Salt Lake wetlands, including a range of conditions from reference to highly degraded. We used nonmetric multidimensional scaling (NMS) to characterize the wetland sites based on the multiple parameters measured in surface water, pore water, and sediment. NMS results showed that the impounded wetlands fall along a gradient of high salinity/low trace element concentrations to low salinity/high trace element concentrations, whereas the sheet flow wetlands have both elevated salinity and high trace element concentrations, reflecting either different sources of element loading or different biogeochemical/hydrological processes operating within the wetlands. Other geochemical distinctions were found among the wetlands, including Fe-reducing conditions at two sites and sulfate-reducing conditions at the remaining sites. Plant community health metrics in the impounded wetlands showed negative correlations with specific metal concentrations in sediment (THg, Cu, Zn, Cd, Sb, Pb, Ag, Tl), and negative correlations with nutrient concentrations in surface water (nitrite, phosphate, nitrate). In the sheet flow wetlands, invasive plant species were inversely correlated with pore water salinity. These results indicate that sediment and pore water chemistry play an important role in wetland plant community health, and that monitoring and

  17. Sphagnum establishment in alkaline fens: Importance of weather and water chemistry.

    Science.gov (United States)

    Vicherová, Eliška; Hájek, Michal; Šmilauer, Petr; Hájek, Tomáš

    2017-02-15

    Sphagnum expansion to alkaline fens has accelerated during the last decades in Europe, leading to changes in diversity, habitat distributions and carbon storage. The causes are still not clearly understood and involve an interplay between climate change, hydrology, nutrient supply and Sphagnum physiology. We conducted a 4-year field experiment in eight fens in Central European highlands and assessed survival and establishment of individual apical shoot fragments of S. flexuosum, S. warnstorfii and S. squarrosum transplanted along the microtopographical gradient. In a laboratory experiment, we tested combined effects of desiccation and high calcium bicarbonate concentration on Sphagnum survival. We found that in unflooded positions, living shoots of Sphagnum and brown mosses lowered [Ca2+] and pH in their capillary water, in contrast to dead fragments; yet without differences between species. Survival and expansion of Sphagnum fragments, which did not die of acute calcium toxicity during first weeks/months, was negatively affected by dry weather and alkaline water chemistry, reflecting Sphagnum intolerance to desiccation and to combined high [Ca2+] and pH. Shoot fragments expanded to patches only when precipitation was high. Interestingly, non-toxic concentration of calcium bicarbonate reduced desiccation damage in Sphagnum, probably through protection of membranes or other cell components. This mechanism would facilitate Sphagnum survival in elevated, frequently desiccated microhabitats of calcareous fens such as brown-moss hummocks. However, since water-retaining capacity of few Sphagnum shoots is insufficient to change water chemistry in its surroundings, surface acidification may occur only once the environment (e.g. sufficient humidity) enabled expansion to larger mats. Then, the retained rainwater together with hardly decomposable Sphagnum litter would separate mire surface from groundwater, speeding up successional shift towards poor fens. Sphagnum expansion

  18. On the interaction between fuel crud and water chemistry in nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Jiaxin Chen [Studsvik Material AB, Nykoeping (Sweden)

    2000-01-01

    This report has surveyed the current understanding about the characteristics of fuel crud, its deposition and dissolution behaviour, the influences of water chemistry, and the radioactivity transport in nuclear power plants. The references were mainly sought for from the International Nuclear Information System (INIS) database and some internal reports of Studsvik Material AB. The characteristics of fuel crud from discharged fuel rods have been extensively investigated over the last three decades. Fuel crud mainly consists of iron, nickel and chromium oxides. For BWR fuel crud the main phases are hematite and nonstoichiometric nickel ferrite spinels. For PWR fuel crud the main phases are nonstoichiometric nickel ferrite and nickel metal or nickel oxide. Fuel crud is usually thin and relatively porous in the outer layer but dense in the inner layer. Important information is lacking about the adhesion property of crud particles or agglomerates on fuel rods. Little, if any, information is reported about the characteristics of fuel crud before discharging in pool. It is uncertain if the fuel crud can, after pool discharge, largely preserve its characteristics appearing during reactor operation. Deposition behaviour of corrosion products on fuel rods, in both solid particles and ionic forms in reactor water, has been well studied in the simulated reactor water environments without irradiation. The influences on deposition rate of pH, heat flux, particle size, crud concentration, and flow rate have also been studied in detail. Most of the experimental observations may be qualitatively explained by the theories developed. However, the importance of each influencing parameter remains largely unknown in the complicated reactor water environments, because irradiation, among various influencing factors, may play an important role. The behaviour of crud dissolution has been extensively studied in various reactor water environments. Generally speaking, the more easily crud

  19. Review: Impacts of permafrost degradation on inorganic chemistry of surface fresh water

    Science.gov (United States)

    Colombo, Nicola; Salerno, Franco; Gruber, Stephan; Freppaz, Michele; Williams, Mark; Fratianni, Simona; Giardino, Marco

    2018-03-01

    Recent studies have shown that climate change is impacting the inorganic chemical characteristics of surface fresh water in permafrost areas and affecting aquatic ecosystems. Concentrations of major ions (e.g., Ca2 +, Mg2 +, SO42 -, NO3-) can increase following permafrost degradation with associated deepening of flow pathways and increased contributions of deep groundwater. In addition, thickening of the active layer and melting of near-surface ground ice can influence inorganic chemical fluxes from permafrost into surface water. Permafrost degradation has also the capability to modify trace element (e.g., Ni, Mn, Al, Hg, Pb) contents in surface water. Although several local and regional modifications of inorganic chemistry of surface fresh water have been attributed to permafrost degradation, a comprehensive review of the observed changes is lacking. The goal of this paper is to distil insight gained across differing permafrost settings through the identification of common patterns in previous studies, at global scale. In this review we focus on three typical permafrost configurations (pervasive permafrost degradation, thermokarst, and thawing rock glaciers) as examples and distinguish impacts on (i) major ions and (ii) trace elements. Consequences of warming climate have caused spatially-distributed progressive increases of major ion and trace element delivery to surface fresh water in both polar and mountain areas following pervasive permafrost degradation. Moreover, localised releases of major ions and trace elements to surface water due to the liberation of soluble materials sequestered in permafrost and ground ice have been found in ice-rich terrains both at high latitude (thermokarst features) and high elevation (rock glaciers). Further release of solutes and related transport to surface fresh water can be expected under warming climatic conditions. However, complex interactions among several factors able to influence the timing and magnitude of the impacts

  20. Anthropogenic impact on water chemistry and benthic macroinvertebrate associated changes in a southern Nigeria stream.

    Science.gov (United States)

    Arimoro, Francis O; Odume, O Nelson; Uhunoma, Samson I; Edegbene, Augustine O

    2015-02-01

    The Ogba River in southern Nigeria is an important water resource for its riparian communities. This study evaluates impact of anthropogenic influences on the Ogba River using water chemistry and macroinvertebrate data sets obtained over a period of 6 months between January and June 2012. Four stations, stations 1-4, characterised by various human activities were chosen along the river. Organic wastes from domestic and industrial sources were the major point sources of pollutants. Station 2 where the municipal wastewater drains into the river had elevated values of flow velocity, BOD5, sulphate, phosphate, nitrate and sodium. Based on the canonical correspondence analysis (CCA), 5-day biochemical oxygen demand (BOD5), sulphate, nitrate and phosphate were the main factors that help to shape the macroinvertebrate assemblage structure of the Ogba River. Macroinvertebrates clustered strongly by stations than by seasons indicating that water quality differences between the stations were responsible for the observed differences in the biotic assemblage. The preponderance of naidid oligochaetes, baetid nymphs and certain tolerant dipteran taxa including chironomids and ceratopogonids at all four stations was an indication that the entire water body was stressed. The odonates were the single most abundant taxa; their dominance could be attributed to the vegetative nature of the stream, favouring odonate colonisation. Overall, the responses of macroinvertebrates to stress were reflected by the different assemblage structures recorded at the four study stations. Substrate and microhabitat obliteration and poor water quality appeared to be the factors responsible for the observed assemblage structure in the Ogba River.

  1. 11-Year change in water chemistry of large freshwater Reservoir Danjiangkou, China

    Science.gov (United States)

    Li, Siyue; Ye, Chen; Zhang, Quanfa

    2017-08-01

    Danjiangkou Reservoir, an important drinking water source, has become a hot spot internationally due to its draining catchment has been increasingly affected by anthropogenic activities. However, its natural water chemistry (major elements) received little attention though it is crucial for water quality and aquatic ecology. Major ions during 2004-2014 were determined using stoichiometry to explore their shifts and the driving factors in the Danjiangkou Reservoir. Results show significant differences in monthly, spatial and annual concentrations of major ions. Waters are controlled by carbonate weathering with the dominant ions of Ca2+ and HCO3- total contributing 74% to the solutes, which are consistent with regional geography. Carbonate dissolution was produced by sulfuric acid and carbonic acid in particular. The relative abundance of Ca2+ gradually decreases, Na+ + K+ abundance, however, has doubled in the recent 11 years. Population and human activities were the major drivers for several major ions, i.e., Cl- and Na+ concentrations were explained by population and GDP, and SO42- by GDP, industrial sewage and energy consumption. Estimation indicated that domestic salts and atmospheric deposition contributed 56% and 22% to Cl-, respectively. We conclude waters in the Reservoir are naturally controlled by rock weathering whilst some key elements largely contributed by anthropogenic activities.

  2. Impact of Water Chemistry, Pipe Material and Stagnation on the Building Plumbing Microbiome.

    Science.gov (United States)

    Ji, Pan; Parks, Jeffrey; Edwards, Marc A; Pruden, Amy

    2015-01-01

    A unique microbiome establishes in the portion of the potable water distribution system within homes and other buildings (i.e., building plumbing). To examine its composition and the factors that shape it, standardized cold water plumbing rigs were deployed at the treatment plant and in the distribution system of five water utilities across the U.S. Three pipe materials (copper with lead solder, CPVC with brass fittings or copper/lead combined pipe) were compared, with 8 hour flush cycles of 10 minutes to simulate typical daily use patterns. High throughput Illumina sequencing of 16S rRNA gene amplicons was employed to profile and compare the resident bulk water bacteria and archaea. The utility, location of the pipe rig, pipe material and stagnation all had a significant influence on the plumbing microbiome composition, but the utility source water and treatment practices were dominant factors. Examination of 21 water chemistry parameters suggested that the total chlorine concentration, pH, P, SO42- and Mg were associated with the most of the variation in bulk water microbiome composition. Disinfectant type exerted a notably low-magnitude impact on microbiome composition. At two utilities using the same source water, slight differences in treatment approaches were associated with differences in rare taxa in samples. For genera containing opportunistic pathogens, Utility C samples (highest pH of 9-10) had the highest frequency of detection for Legionella spp. and lowest relative abundance of Mycobacterium spp. Data were examined across utilities to identify a true universal core, special core, and peripheral organisms to deepen insight into the physical and chemical factors that shape the building plumbing microbiome.

  3. Impact of Water Chemistry, Pipe Material and Stagnation on the Building Plumbing Microbiome.

    Directory of Open Access Journals (Sweden)

    Pan Ji

    Full Text Available A unique microbiome establishes in the portion of the potable water distribution system within homes and other buildings (i.e., building plumbing. To examine its composition and the factors that shape it, standardized cold water plumbing rigs were deployed at the treatment plant and in the distribution system of five water utilities across the U.S. Three pipe materials (copper with lead solder, CPVC with brass fittings or copper/lead combined pipe were compared, with 8 hour flush cycles of 10 minutes to simulate typical daily use patterns. High throughput Illumina sequencing of 16S rRNA gene amplicons was employed to profile and compare the resident bulk water bacteria and archaea. The utility, location of the pipe rig, pipe material and stagnation all had a significant influence on the plumbing microbiome composition, but the utility source water and treatment practices were dominant factors. Examination of 21 water chemistry parameters suggested that the total chlorine concentration, pH, P, SO42- and Mg were associated with the most of the variation in bulk water microbiome composition. Disinfectant type exerted a notably low-magnitude impact on microbiome composition. At two utilities using the same source water, slight differences in treatment approaches were associated with differences in rare taxa in samples. For genera containing opportunistic pathogens, Utility C samples (highest pH of 9-10 had the highest frequency of detection for Legionella spp. and lowest relative abundance of Mycobacterium spp. Data were examined across utilities to identify a true universal core, special core, and peripheral organisms to deepen insight into the physical and chemical factors that shape the building plumbing microbiome.

  4. Surveillance for waterborne disease and outbreaks associated with drinking water and water not intended for drinking--United States, 2003-2004.

    Science.gov (United States)

    Liang, Jennifer L; Dziuban, Eric J; Craun, Gunther F; Hill, Vincent; Moore, Matthew R; Gelting, Richard J; Calderon, Rebecca L; Beach, Michael J; Roy, Sharon L

    2006-12-22

    Since 1971, CDC, the U.S. Environmental Protection Agency (EPA), and the Council of State and Territorial Epidemiologists have maintained a collaborative Waterborne Disease and Outbreaks Surveillance System for collecting and reporting data related to occurrences and causes of waterborne disease and outbreaks (WBDOs). This surveillance system is the primary source of data concerning the scope and effects of WBDOs in the United States. Data presented summarize 36 WBDOs that occurred during January 2003-December 2004 and nine previously unreported WBDOs that occurred during 1982-2002. The surveillance system includes data on WBDOs associated with drinking water, water not intended for drinking (excluding recreational water), and water of unknown intent. Public health departments in the states, territories, localities, and Freely Associated States (i.e., the Republic of the Marshall Islands, the Federated States of Micronesia, and the Republic of Palau, formerly parts of the U.S.-administered Trust Territory of the Pacific Islands) are primarily responsible for detecting and investigating WBDOs and voluntarily reporting them to CDC by using a standard form. During 2003-2004, a total of 36 WBDOs were reported by 19 states; 30 were associated with drinking water, three were associated with water not intended for drinking, and three were associated with water of unknown intent. The 30 drinking water-associated WBDOs caused illness among an estimated 2,760 persons and were linked to four deaths. Etiologic agents were identified in 25 (83.3%) of these WBDOs: 17 (68.0%) involved pathogens (i.e., 13 bacterial, one parasitic, one viral, one mixed bacterial/parasitic, and one mixed bacterial/parasitic/viral), and eight (32.0%) involved chemical/toxin poisonings. Gastroenteritis represented 67.7% of the illness related to drinking water-associated WBDOs; acute respiratory illness represented 25.8%, and dermatitis represented 6.5%. The classification of deficiencies contributing

  5. Links between climate change, water-table depth, and water chemistry in a mineralized mountain watershed

    Science.gov (United States)

    Manning, Andrew H.; Verplanck, Philip L.; Caine, Jonathan S.; Todd, Andrew S.

    2013-01-01

    Recent studies suggest that climate change is causing rising solute concentrations in mountain lakes and streams. These changes may be more pronounced in mineralized watersheds due to the sensitivity of sulfide weathering to changes in subsurface oxygen transport. Specific causal mechanisms linking climate change and accelerated weathering rates have been proposed, but in general remain entirely hypothetical. For mineralized watersheds, a favored hypothesis is that falling water tables caused by declining recharge rates allow an increasing volume of sulfide-bearing rock to become exposed to air, thus oxygen. Here, we test the hypothesis that falling water tables are the primary cause of an increase in metals and SO4 (100-400%) observed since 1980 in the Upper Snake River (USR), Colorado. The USR drains an alpine watershed geologically and climatologically representative of many others in mineralized areas of the western U.S. Hydrologic and chemical data collected from 2005 to 2011 in a deep monitoring well (WP1) at the top of the USR watershed are utilized. During this period, both water table depths and groundwater SO4 concentrations have generally increased in the well. A numerical model was constructed using TOUGHREACT that simulates pyrite oxidation near WP1, including groundwater flow and oxygen transport in both saturated and unsaturated zones. The modeling suggests that a falling water table could produce an increase in metals and SO4 of a magnitude similar to that observed in the USR (up to 300%). Future water table declines may produce limited increases in sulfide weathering high in the watershed because of the water table dropping below the depth of oxygen penetration, but may continue to enhance sulfide weathering lower in the watershed where water tables are shallower. Advective air (oxygen) transport in the unsaturated zone caused by seasonally variable recharge and associated water table fluctuations was found to have little influence on pyrite

  6. Monitoring and Surveillance of Marine Invasive Species in Californian Waters by DNA Barcoding: Methodological and Analytical Solutions

    Science.gov (United States)

    Campbell, T. L.; Geller, J. B.; Heller, P.; Ruiz, G.; Chang, A.; McCann, L.; Ceballos, L.; Marraffini, M.; Ashton, G.; Larson, K.; Havard, S.; Meagher, K.; Wheelock, M.; Drake, C.; Rhett, G.

    2016-02-01

    The Ballast Water Management Act, the Marine Invasive Species Act, and the Coastal Ecosystem Protection Act require the California Department of Fish and Wildlife to monitor and evaluate the extent of biological invasions in the state's marine and estuarine waters. This has been performed statewide, using a variety of methodologies. Conventional sample collection and processing is laborious, slow and costly, and may require considerable taxonomic expertise requiring detailed time-consuming microscopic study of multiple specimens. These factors limit the volume of biomass that can be searched for introduced species. New technologies continue to reduce the cost and increase the throughput of genetic analyses, which become efficient alternatives to traditional morphological analysis for identification, monitoring and surveillance of marine invasive species. Using next-generation sequencing of mitochondrial Cytochrome c oxidase subunit I (COI) and nuclear large subunit ribosomal RNA (LSU), we analyzed over 15,000 individual marine invertebrates collected in Californian waters. We have created sequence databases of California native and non-native species to assist in molecular identification and surveillance in North American waters. Metagenetics, the next-generation sequencing of environmental samples with comparison to DNA sequence databases, is a faster and cost-effective alternative to individual sample analysis. We have sequenced from biomass collected from whole settlement plates and plankton in California harbors, and used our introduced species database to create species lists. We can combine these species lists for individual marinas with collected environmental data, such as temperature, salinity, and dissolved oxygen to understand the ecology of marine invasions. Here we discuss high throughput sampling, sequencing, and COASTLINE, our data analysis answer to challenges working with hundreds of millions of sequencing reads from tens of thousands of specimens.

  7. A preliminary study of the chemistry of pore water extracted from tuff by one-dimensional compression

    Energy Technology Data Exchange (ETDEWEB)

    Kharaka, Y.K.; Maest, A.S. [eds.] [Geological Survey, Menlo Park, CA (United States); Peters, C.A.; Yang, I.C. [Geological Survey, Denver, CO (United States); Higgins, J.D. [Colorado School of Mines, Golden, CO (United States); Burger, P.A. [Bureau of Reclamation, Denver, CO (United States)

    1992-10-01

    A specially designed and fabricated one-dimensional compression cell is being used to extract water from nonwelded and densely welded tuffs having degrees of saturation greater than 16 and 37 percent respectively. Chemical analyses of pore water obtained at increasing pressures are used to evaluate possible changes in chemistry caused by compression. The extracted pore water varies form a calcium chloride type to a sodium bicarbonate type. The mean concentration of dissolved ions generally decreases during compression. The relative abundance of the major cations varies little with increasing pressure. Possible causes of the pore-water-chemistry changes include: (1) dilution of pore water by low ionic strength adsorbed water from zeolites and clays; (2) dissolution reactions caused by the increase in dissolved carbon dioxide concentrations that may result from pressurization; (3) membrane filtration by zeolites and clays; and (4) ion exchange with the zeolites and clays.

  8. Toxicogenomics of water chemistry influence on chronic lead exposure to the fathead minnow (Pimephales promelas).

    Science.gov (United States)

    Mager, Edward M; Wintz, Henri; Vulpe, Chris D; Brix, Kevin V; Grosell, Martin

    2008-05-01

    Establishment of water quality criteria (WQC), intended to protect aquatic life, continues to rely principally on water hardness (i.e. Ca(2+)) for lead (Pb) despite growing evidence that other chemical parameters also strongly influence toxicity. To more clearly define the water chemistry parameters mediating Pb toxicity, we evaluated the effects of hardness as CaSO(4) and dissolved organic carbon (DOC) as humic acid during chronic (150 days) exposures to the fathead minnow. Measured Pb concentrations ranged from 157+/-5 nM (33+/-1 microg/L) Pb in base water to 177+/-7 (37+/-1 microg/L) and 187+/-7 nM (39+/-1 microg/L) Pb in CaSO(4)- or HA-supplemented water, respectively. Fish were collected at 2, 4, 10, 30, 63, 90 and 150 days of exposure. Traditional toxicological endpoints were examined alongside gene transcription analyses to help clarify the underlying mechanisms of Pb toxicity and to identify candidate molecular markers that might ultimately serve as robust indicators of exposure and effect. Addition of CaSO(4) did not prevent whole body Pb accumulation whereas DOC afforded strong protection (about half the amount accumulated by fish in base water) suggesting that current, hardness-based WQC are likely inaccurate for predicting chronic Pb effects in aquatic systems. Custom-made microarrays were co-hybridized with base water samples+/-Pb up to the 30 days time point. Quantitative PCR was employed to verify gene transcription responses and to extend analysis to the CaSO(4) and HA treatments and the 150 days time point. Identification of four genes by microarray analysis revealed clear Pb-induced responses over time: glucose-6-phosphate dehydrogenase, glutathione-S-transferase, ferritin and beta-globin. Results obtained by qPCR were in strong agreement with microarray data by regression analysis (r(2)=0.82, slope=1.28). The associated pathways implicated herein for these genes provide further evidence supporting roles for anemia and neurological disorders in

  9. Beyond the Clean Water Rule: Impacts of a Non-Jurisdictional Ditch on Headwater Stream Discharge and Water Chemistry

    Directory of Open Access Journals (Sweden)

    John P. Gannon

    2016-12-01

    Full Text Available Ephemeral drainage ditches in upland areas, such as those draining roads, are excluded from the jurisdiction of the U.S. Clean Water Act (CWA. While several studies have shown that road drainage and/or development in forested watersheds can impact water quality, the direct physical and chemical impacts of a single drainage ditch have not been identified. In this study, we measured water chemistry (silicon, calcium, and sulfate and magnitude of discharge from one such feature and at the outlet of the catchment it is within. We found that discharge from the drainage ditch was sometimes over 10% of the larger stream into which it drains, despite the small relative size of the ditch catchment (1.1 ha compared to the main catchment (43 ha. Furthermore, we observed sharp decreases in silicon and calcium and increases in sulfate concentrations downstream from the drainage ditch across longitudinal sampling of the stream network. This illustrates the impacts of a common feature in high relief, forested areas that when aggregated over the landscape are likely responsible for regional water quality impacts.

  10. Physicochemical effects of temperature and water chemistry on cohesive channel erosion

    Science.gov (United States)

    Wynn-Thompson, T.; Hoomehr, S.; Parks, O.; Eick, M.

    2013-12-01

    One potential unforeseen consequence urbanization and climate change is accelerated stream channel erosion due to increased stream temperatures and changes in stream chemistry, which affect the surface potential and hence the stability of soil colloids. Summer thunderstorms in urban watersheds can increase stream temperature more than 7 degC and the impact of global warming on average stream temperature is already evident in some stream systems. The goal of this research was to evaluate the impact of changes in stream chemistry commonly observed in urban watersheds, and expected to occur due to climate change, on the fluvial erosion of cohesive streambank soils. We hypothesized that increases in stream temperature and changes in stream pH and salt concentrations alter the surface potential of clay particles, affecting soil erodibility. We tested this hypothesis by measuring the erosion rate of two riparian soils dominated by different common phyllosilicate clays in a recirculating hydraulic flume. Two pH levels (6, 8), three water temperatures (10 degC, 20 degC, 30 degC), and two NaCl concentrations (5 mg/l, 5 g/l) were analyzed. Velocity profiles and the distance to the soil sample were measured using a Sontek Vectrino II acoustic Doppler profiler. Additionally, zetapotential was measured to determine if erosion rates were correlated to changes in clay surface potential due to varying water chemistry. Initial study results indicated significant increases in erosion rates for both clay types with decreasing pH and increasing water temperature; temperature effects were more significant than pH effects. Changes in erosion rates with salt concentration were only significant for the soil with montmorillonite clay. While the research is ongoing, these initial results could have wide-ranging implications for climate change and urban stormwater management. Assuming climate change will result in higher stream temperatures and lower stream pH, streambank erosion could

  11. Natural and anthropogenic sources and processes affecting water chemistry in two South Korean streams

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Woo-Jin [Division of Earth and Environmental Sciences, Korea Basic Science Institute, Cheongwon-gun, Chungbuk 363-883 (Korea, Republic of); Department of Geoscience, University of Calgary, Calgary, Alberta T2N 1N4 (Canada); Ryu, Jong-Sik [Division of Earth and Environmental Sciences, Korea Basic Science Institute, Cheongwon-gun, Chungbuk 363-883 (Korea, Republic of); Mayer, Bernhard [Department of Geoscience, University of Calgary, Calgary, Alberta T2N 1N4 (Canada); Lee, Kwang-Sik, E-mail: kslee@kbsi.re.kr [Division of Earth and Environmental Sciences, Korea Basic Science Institute, Cheongwon-gun, Chungbuk 363-883 (Korea, Republic of); Lee, Sin-Woo [Division of Earth and Environmental Sciences, Korea Basic Science Institute, Cheongwon-gun, Chungbuk 363-883 (Korea, Republic of); Department of Geology, Chungnam National University, Yuseong-gu, Daejeon 305-764 (Korea, Republic of)

    2014-07-01

    Acid mine drainage (AMD) in a watershed provides potential sources of pollutants for surface and subsurface waters that can deteriorate water quality. Between March and early August 2011, water samples were collected from two streams in South Korea, one dominantly draining a watershed with carbonate bedrock affected by coal mines and another draining a watershed with silicate bedrock and a relatively undisturbed catchment area. The objective of the study was to identify the sources and processes controlling water chemistry, which was dependent on bedrock and land use. In the Odae stream (OS), the stream in the silicate-dominated catchment, Ca, Na, and HCO{sub 3} were the dominant ions and total dissolved solids (TDS) was low (26.1–165 mg/L). In the Jijang stream (JS), in the carbonate-dominated watershed, TDS (224–434 mg/L) and ion concentrations were typically higher, and Ca and SO{sub 4} were the dominant ions due to carbonate weathering and oxidation of pyrite exposed at coal mines. Dual isotopic compositions of sulfate (δ{sup 34}S{sub SO4} and δ{sup 18}O{sub SO4}) verified that the SO{sub 4} in JS is derived mainly from sulfide mineral oxidation in coal mines. Cl in JS was highest upstream and decreased progressively downstream, which implies that pollutants from recreational facilities in the uppermost part of the catchment are the major source governing Cl concentrations within the discharge basin. Dual isotopic compositions of nitrate (δ{sup 15}N{sub NO3} and δ{sup 18}O{sub NO3}) indicated that NO{sub 3} in JS is attributable to nitrification of soil organic matter but that NO{sub 3} in OS is derived mostly from manure. Additionally, the contributions of potential anthropogenic sources to the two streams were estimated in more detail by using a plot of δ{sup 34}S{sub SO4} and δ{sup 15}N{sub NO3}. This study suggests that the dual isotope approach for sulfate and nitrate is an excellent additional tool for elucidating the sources and processes

  12. Effect of irrigation water salinity and sodicity and water table position on water table chemistry beneath Atriplex lentiformis and Hordeum marinum

    Energy Technology Data Exchange (ETDEWEB)

    Browning, L.S.; Bauder, J.W.; Phelps, S.D. [Montana State University, Bozeman, MT (United States)

    2006-04-15

    Coal bed methane (CBM) extraction in Montana and Wyoming's Powder River Basin (PRB) produces large quantities of modestly saline-sodic water. This study assessed effects of irrigation water quality and water table position on water chemistry of closed columns, simulating a perched or a shallow water table. The experiment assessed the potential salt loading in areas where shallow or perched water tables prevent leaching or where artificial drainage is not possible. Water tables were established in sand filled PVC columns at 0.38, 0.76, and1.14 m below the surface, after which columns were planted to one of three species, two halophytic Atriplex spp. and Hordeum marinum Huds. (maritime barley), a glycophyte. As results for the two Atriplex ssp. did not differ much, only results from Atriplex lentiformis (Torn) S. Wats. (big saltbush) and H. marinum are presented. Irrigation water representing one of two irrigation sources was used: Powder River (PR) (electrolytic conductivity (EC) = 0.19 Sm{sup -1}, sodium adsorption ratio (SAR) = 3.5) or CBM water (EC = 0.35 Sm-1, SAR = 10.5). Continuous irrigation with CBM and PR water led to salt loading over time, the extent being proportional to the salinity and sodicity of applied water. Water in columns planted to A. lentiformis with water tables maintained at 0.38 m depth had greater EC and SAR values than those with 0.76 and 1.14 m water table positions. Elevated EC and SAR values most likely reflect the shallow rooted nature of A. lentiformis, which resulted in enhanced ET with the water table close to the soil surface.

  13. Using initial field campaigns for optimal placement of high resolution stable water isotope and water chemistry measurements

    Science.gov (United States)

    Sahraei, Amirhossein; Kraft, Philipp; Windhorst, David; Orlowski, Natalie; Bestian, Konrad; Holly, Hartmut; Breuer, Lutz

    2017-04-01

    composition and groundwater is not reactive to the annual precipitation cycle. Consecutive runoff measurements revealed bidirectional water exchange between stream and groundwater where influent and effluent conditions occur at different stream sections during baseflow conditions. Moreover, stream water quality responds to land use with significant variation of nitrate concentration due to agricultural land use. The a priori assessment of information from various sources and methods will allow us to guide the placement of high resolution stable water isotope and water chemistry measurements. We will report on the merits and drawbacks of each approach. Results will be used to select up to 12 sampling sites for a novel self-sufficient measurement system and guide the method selection for other researchers facing a similar challenge.

  14. AUTOMATED DEAD-END ULTRAFILTRATION FOR ENHANCED SURVEILLANCE OF LEGIONELLA 2 PNEUMOPHILA AND LEGIONELLA SPP. IN COOLING TOWER WATERS

    Energy Technology Data Exchange (ETDEWEB)

    Brigmon, R.; Leskinen, S.; Kearns, E.; Jones, W.; Miller, R.; Betivas, C.; Kingsley, M.; Lim, D.

    2011-10-10

    Detection of Legionella pneumophila in cooling towers and domestic hot water systems involves concentration by centrifugation or membrane filtration prior to inoculation onto growth media or analysis using techniques such as PCR or immunoassays. The Portable Multi-use Automated Concentration System (PMACS) was designed for concentrating microorganisms from large volumes of water in the field and was assessed for enhancing surveillance of L. pneumophila at the Savannah River Site, SC. PMACS samples (100 L; n = 28) were collected from six towers between August 2010 and April 2011 with grab samples (500 ml; n = 56) being collected before and after each PMACS sample. All samples were analyzed for the presence of L. pneumophila by direct fluorescence immunoassay (DFA) using FITC-labeled monoclonal antibodies targeting serogroups 1, 2, 4 and 6. QPCR was utilized for detection of Legionella spp. in the same samples. Counts of L. pneumophila from DFA and of Legionella spp. from qPCR were normalized to cells/L tower water. Concentrations were similar between grab and PMACS samples collected throughout the study by DFA analysis (P = 0.4461; repeated measures ANOVA). The same trend was observed with qPCR. However, PMACS concentration proved advantageous over membrane filtration by providing larger volume, more representative samples of the cooling tower environment, which led to reduced variability among sampling events and increasing the probability of detection of low level targets. These data highlight the utility of the PMACS for enhanced surveillance of L. pneumophila by providing improved sampling of the cooling tower environment.

  15. Effect of water chemistry upsets on the dynamics of corrective reagent dosing systems at thermal power stations

    Science.gov (United States)

    Voronov, V. N.; Yegoshina, O. V.; Bolshakova, N. A.; Yarovoi, V. O.; Latt, Aie Min

    2016-12-01

    Typical disturbances in the dynamics of a corrective reagent dosing system under unsteady-state conditions during the unsatisfactory operation of a chemical control system with some water chemistry upsets at thermal and nuclear power stations are considered. An experimental setup representing a physical model for the water chemistry control system is described. The two disturbances, which are most frequently encountered in water chemistry control practice, such as a breakdown or shutdown of temperature compensation during pH measurement and an increase in the heat-transfer fluid flow rate, have been modeled in the process of study. The study of the effect produced by the response characteristics of chemical control analyzers on the operation of a reagent dosing system under unsteady-state conditions is important for the operative control of a water chemistry regime state. The effect of temperature compensation during pH measurement on the dynamics of an ammonia-dosing system in the manual and automatic cycle chemistry control modes has been studied. It has been demonstrated that the reading settling time of a pH meter in the manual ammonia- dosing mode grows with a breakdown in temperature compensation and a simultaneous increase in the temperature of a heat-transfer fluid sample. To improve the efficiency of water chemistry control, some systems for the quality control of a heat-transfer fluid by a chemical parameter with the obligatory compensation of a disturbance in its flow rate have been proposed for use. Experimental results will possibly differ from industrial data due to a great length of sampling lines. For this reason, corrective reagent dosing systems must be adapted to the conditions of a certain power-generating unit in the process of their implementation.

  16. Urban and Suburban Influences on Water Chemistry in Washington DC: Impervious Surfaces and Urban Stream Syndrome

    Science.gov (United States)

    MacAvoy, S. E.; Petersen, E.

    2015-12-01

    Among the challenges facing urban rivers are water stormwater runoff problems and changing water chemistry, not only from air and water pollution sources, but also from altered geology with the development of "urban karst". Seventy five percent of the Anacostia River in Washington, D.C. is urban or impervious. The Anacostia River experiences environmental challenges similar to those of other urban industrial rivers (heavy metal, PCB and PAH contamination). It also has Ca/Sr ratios above 200, and Na concentrations higher than Ca, and elevated ionic strength, all associated with extended chemical interaction with concrete. While these chemical characteristics have been documented in the urban areas within DC, they have not been examined in the largely suburban/mixed development tributaries of the Anacostia. Here we examine the base-flow geochemistry of the Anacostia River and its suburban tributaries (6 locations) over a year (November 2014- August 2015), concentrating on the following water chemistry variables: pH, hardness, SAR, alkalinity, Ca, Mg, Na, K, Fe, Mn, Zn, Al, Ba, Ni, total P, S, Sr, NO3-, NH4+, PO43-. NO3- and NH4+ were generally lowest in at all sites in January, but rose to between 0.5 and 2.4 mg/L in June, with highest NO3- concentrations in suburban areas. Na and Cl concentrations were 5x higher in suburban areas than urban areas during the winter months. Ca/Sr concentration ratios, were between 120 and 200 for suburban sites but increased as the sites became more urban (to a high of 240 for the most urban site). These trends have been observed in other urban streams, and correlate with percent impervious area. The data follow patterns expected for "urban stream syndrome" and dissolution of concrete. Suburban areas, with their relatively small streams, show greater winter salting effects than more urban areas down stream. Suburban areas also show higher NO3- (and occasionally higher NH4+) than urban areas except in winter. The data presented here

  17. Inland dissolved salt chemistry: statistical evaluation of bivariate and ternary diagram models for surface and subsurface waters

    Directory of Open Access Journals (Sweden)

    Stephen T. THRELKELD

    2000-08-01

    Full Text Available We compared the use of ternary and bivariate diagrams to distinguish the effects of atmospheric precipitation, rock weathering, and evaporation on inland surface and subsurface water chemistry. The three processes could not be statistically differentiated using bivariate models even if large water bodies were evaluated separate from small water bodies. Atmospheric precipitation effects were identified using ternary diagrams in water with total dissolved salts (TDS 1000 mg l-1. A principal components analysis showed that the variability in the relative proportions of the major ions was related to atmospheric precipitation, weathering, and evaporation. About half of the variation in the distribution of inorganic ions was related to rock weathering. By considering most of the important inorganic ions, ternary diagrams are able to distinguish the contributions of atmospheric precipitation, rock weathering, and evaporation to inland water chemistry.

  18. Surveillance of bacteriological quality of drinking water in Chandigarh, northern India.

    Science.gov (United States)

    Goel, Naveen K; Pathak, Rambha; Gulati, Sangeeta; Balakrishnan, S; Singh, Navpreet; Singh, Hardeep

    2015-09-01

    The study was carried out in Chandigarh, India with the following objectives: (1) to monitor the bacteriological quality of drinking water; (2) to collect data on bacteriological contamination of water collected at point of use; (3) to test both groundwater being supplied through hand pumps and pre-treated water; and (4) to determine the pattern of seasonal variations in quality of water. The community-based longitudinal study was carried out from 2002 to 2007. Water samples from hand pumps and tap water were collected from different areas of Chandigarh following a simple random sampling strategy. The time trends and seasonal variations in contamination of water according to area and season were analysed. It was found that the contamination of water was higher during the pre-monsoon period compared with the rest of the year. The water being used in slums and rural areas for drinking purposes also had higher contamination levels than urban areas, with highest levels in rural areas. This study found that drinking water supply in Chandigarh is susceptible to contamination especially in rural areas and during pre-monsoon. Active intervention from public health and the health department along with raising people's awareness regarding water hygiene are required for improving the quality of drinking water.

  19. Multivariate Statistical Analysis of Water Chemistry in Evaluating the Origin of Contamination in Many Devils Wash, Shiprock, New Mexico

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    2012-12-31

    This report evaluates the chemistry of seep water occurring in three desert drainages near Shiprock, New Mexico: Many Devils Wash, Salt Creek Wash, and Eagle Nest Arroyo. Through the use of geochemical plotting tools and multivariate statistical analysis techniques, analytical results of samples collected from the three drainages are compared with the groundwater chemistry at a former uranium mill in the Shiprock area (the Shiprock site), managed by the U.S. Department of Energy Office of Legacy Management. The objective of this study was to determine, based on the water chemistry of the samples, if statistically significant patterns or groupings are apparent between the sample populations and, if so, whether there are any reasonable explanations for those groupings.

  20. Effects of water chemistry on arsenic removal from drinking water by electrocoagulation.

    Science.gov (United States)

    Wan, Wei; Pepping, Troy J; Banerji, Tuhin; Chaudhari, Sanjeev; Giammar, Daniel E

    2011-01-01

    Exposure to arsenic through drinking water poses a threat to human health. Electrocoagulation is a water treatment technology that involves electrolytic oxidation of anode materials and in-situ generation of coagulant. The electrochemical generation of coagulant is an alternative to using chemical coagulants, and the process can also oxidize As(III) to As(V). Batch electrocoagulation experiments were performed in the laboratory using iron electrodes. The experiments quantified the effects of pH, initial arsenic concentration and oxidation state, and concentrations of dissolved phosphate, silica and sulfate on the rate and extent of arsenic removal. The iron generated during electrocoagulation precipitated as lepidocrocite (γ-FeOOH), except when dissolved silica was present, and arsenic was removed by adsorption to the lepidocrocite. Arsenic removal was slower at higher pH. When solutions initially contained As(III), a portion of the As(III) was oxidized to As(V) during electrocoagulation. As(V) removal was faster than As(III) removal. The presence of 1 and 4 mg/L phosphate inhibited arsenic removal, while the presence of 5 and 20 mg/L silica or 10 and 50 mg/L sulfate had no significant effect on arsenic removal. For most conditions examined in this study, over 99.9% arsenic removal efficiency was achieved. Electrocoagulation was also highly effective at removing arsenic from drinking water in field trials conducted in a village in Eastern India. By using operation times long enough to produce sufficient iron oxide for removal of both phosphate and arsenate, the performance of the systems in field trials was not inhibited by high phosphate concentrations. Copyright © 2010 Elsevier Ltd. All rights reserved.

  1. Water chemistry in Kuji river. Its spatial and seasonal variations in major ions and organic substances

    Energy Technology Data Exchange (ETDEWEB)

    Niina, Toshiaki; Matsunaga, Takeshi; Amano, Hikaru [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1996-02-01

    As a basic research with a aim to clarify the migration behavior of radionuclides in rivers, the characteristics of dissolved ions and organic substances in river water, which characteristics may affect the behavior, was investigated. The investigation was carried out for the Kuji river in the northern Kanto district (Japan) comprising four sampling campaigns in 1994 for 10 locations from the upstream to the downstream. Concentrations of major ions, iron and manganese species and organic substances were analyzed in laboratory. Values of temperature of the water, pH, conductivity, dissolved oxygen were measured in the field. This investigation was conducted mainly under low water flow conditions of the river, while a limited number of campaigns were under high flow conditions due to precipitation events. The concentrations of major inorganic ions increased steadily toward the down-stream, resulting in approximately two times increase for the traveling distance of 100 km. They showed a seasonal variation that they were highest in the spring and lowest in the autumn when there were most concentrated precipitation events in a year. The constituents were mainly Na{sup +}, Ca{sup 2+}, SO{sub 4}{sup 2-} and HCO{sub 3}{sup -}, and were similar for every sampling locations and seasons. Concentrations of dissolved organic substances (carbon compounds) were lowest in the upstream and increased about twice in the downstream as well as major inorganic ions. Their level was 1-3 mg/l, which can be ranked as relatively lower in general values for fresh water environments. They were highest in the spring (average over the locations: 2.2 mg/l) and lowest in the autumn (1.3 mg/l) and also in the winter (1.3 mg/l). These results will be useful as a basic understanding of spatial and seasonal variations of river water chemistry, especially related to the organic substances which can bind with radionuclides to make a mobile complex. (author).

  2. Mineralogy, early marine diagenesis, and the chemistry of shallow-water carbonate sediments

    Science.gov (United States)

    Higgins, J. A.; Blättler, C. L.; Lundstrom, E. A.; Santiago-Ramos, D. P.; Akhtar, A. A.; Crüger Ahm, A.-S.; Bialik, O.; Holmden, C.; Bradbury, H.; Murray, S. T.; Swart, P. K.

    2018-01-01

    Shallow-water carbonate sediments constitute the bulk of sedimentary carbonates in the geologic record and are widely used archives of Earth's chemical and climatic history. One of the main limitations in interpreting the geochemistry of ancient carbonate sediments is the potential for post-depositional diagenetic alteration. In this study, we use paired measurements of calcium (44Ca/40Ca or δ44Ca) and magnesium (26Mg/24Mg or δ26Mg) isotope ratios in sedimentary carbonates and associated pore-fluids as a tool to understand the mineralogical and diagenetic history of Neogene shallow-water carbonate sediments from the Bahamas and southwest Australia. We find that the Ca and Mg isotopic composition of bulk carbonate sediments at these sites exhibits systematic stratigraphic variability that is related to both mineralogy and early marine diagenesis. The observed variability in bulk sediment Ca isotopes is best explained by changes in the extent and style of early marine diagenesis from one where the composition of the diagenetic carbonate mineral is determined by the chemistry of the fluid (fluid-buffered) to one where the composition of the diagenetic carbonate mineral is determined by the chemistry of the precursor sediment (sediment-buffered). Our results indicate that this process, together with variations in carbonate mineralogy (aragonite, calcite, and dolomite), plays a fundamental and underappreciated role in determining the regional and global stratigraphic expressions of geochemical tracers (δ13C, δ18O, major, minor, and trace elements) in shallow-water carbonate sediments in the geologic record. Our results also provide evidence that a large shallow-water carbonate sink that is enriched in 44Ca can explain the mismatch between the δ44/40Ca value of rivers and deep-sea carbonate sediments and call into question the hypothesis that the δ44/40Ca value of seawater depends on the mineralogy of primary carbonate precipitations (e.g. 'aragonite seas' and

  3. Mineralogy and geochemistry of efflorescent minerals on mine tailings and their potential impact on water chemistry.

    Science.gov (United States)

    Grover, B P C; Johnson, R H; Billing, D G; Weiersbye, I M G; Tutu, H

    2016-04-01

    In the gold mining Witwatersrand Basin of South Africa, efflorescent mineral crusts are a common occurrence on and nearby tailings dumps during the dry season. The crusts are readily soluble and generate acidic, metal- and sulphate-rich solutions on dissolution. In this study, the metal content of efflorescent crusts at an abandoned gold mine tailings dump was used to characterise surface and groundwater discharges from the site. Geochemical modelling of the pH of the solution resulting from the dissolution of the crusts was used to better understand the crusts' potential impact on water chemistry. The study involved two approaches: (i) conducting leaching experiments on oxidised and unoxidised tailings using artificial rainwater and dilute sulphuric acid and correlating the composition of crusts to these leachates and (ii) modelling the dissolution of the crusts in order to gain insight into their mineralogy and their potential impact on receiving waters. The findings suggested that there were two chemically distinct discharges from the site, namely an aluminium- and magnesium-rich surface water plume and an iron-rich groundwater plume. The first plume was observed to originate from the oxidised tailings following leaching with rainwater while the second plume originated from the underlying unoxidised tailings with leaching by sulphuric acid. Both groups of minerals forming from the respective plumes were found to significantly lower the pH of the receiving water with simulations of their dissolution found to be within 0.2 pH units of experimental values. It was observed that metals in a low abundance within the crust (for example, iron) had a stronger influence on the pH of the resulting solutions than metals in a greater abundance (aluminium or magnesium). Techniques such as powder X-ray diffraction (PXRD) and in situ mineral determination techniques such as remote sensing can effectively determine the dominant mineralogy. However, the minerals or metals

  4. Involvement of stakeholders in the water quality monitoring and surveillance system: The case of Mzingwane Catchment, Zimbabwe

    Science.gov (United States)

    Nare, Lerato; Love, David; Hoko, Zvikomborero

    Stakeholder participation is viewed as critical in the current water sector reforms taking place in the Southern African region. In Zimbabwe, policies and legislation encourage stakeholder participation. A study was undertaken to determine the extent of stakeholder participation in water quality monitoring and surveillance at the operational level, and also to assess indigenous knowledge and practices in water quality monitoring. Two hundred and forty one questionnaires were administered in Mzingwane Catchment, the portion of the Limpopo Basin that falls within Zimbabwe. The focus was on small users in rural communities, whose experiences were captured using a questionnaire and focus group discussions. Extension workers, farmers and NGOs and relevant sector government ministries and departments were also interviewed and a number of workshops held. Results indicate that there is very limited stakeholder participation despite the presence of adequate supportive structures and organisations. For the Zimbabwe National Water Authority (ZINWA), stakeholders are the paying permit holders to whom feedback is given following analysis of samples. However, the Ministry of Health and Child Welfare generally only releases information to rural communities when it is deemed necessary for their welfare. There are no guidelines on how a dissatisfied member of the public can raise a complaint - although some stakeholders carry such complaints to Catchment Council meetings. With regard to water quality, the study revealed widespread use of indigenous knowledge and practice by communities. Such knowledge is based on smell, taste, colour and odour perceptions. Residents are generally more concerned about the physical parameters than the bacteriological quality of water. They are aware of what causes water pollution and the effects of pollution on human health, crops, animals and aquatic ecology. They have ways of preventing pollution and appropriate interventions to take when a source

  5. Groundwater, surface-water, and water-chemistry data, Black Mesa area, northeastern Arizona—2013–2015

    Science.gov (United States)

    Macy, Jamie P.; Mason, Jon P.

    2017-12-07

    The Navajo (N) aquifer is an extensive aquifer and the primary source of groundwater in the 5,400-square-mile Black Mesa area in northeastern Arizona. Availability of water is an important issue in northeastern Arizona because of continued water requirements for industrial and municipal use by a growing population and because of low precipitation in the arid climate of the Black Mesa area. Precipitation in the area typically is between 6 and 16 inches per year.The U.S. Geological Survey water-monitoring program in the Black Mesa area began in 1971 and provides information about the long-term effects of groundwater withdrawals from the N aquifer for industrial and municipal uses. This report presents results of data collected as part of the monitoring program in the Black Mesa area from January 2013 to December 2015. The monitoring program includes measurements of (1) groundwater withdrawals (pumping), (2) groundwater levels, (3) spring discharge, (4) surface-water discharge, and (5) groundwater chemistry.In 2013, total groundwater withdrawals were 3,980 acre-feet (ft), in 2014 total withdrawals were 4,170 acre-ft, and in 2015 total withdrawals were 3,970 acre-ft. From 2013 to 2015 total withdrawals varied by less than 5 percent.From 2014 to 2015, annually measured water levels in the Black Mesa area declined in 9 of 15 wells that were available for comparison in the unconfined areas of the N aquifer, and the median change was -0.1 feet. Water levels declined in 3 of 16 wells measured in the confined area of the aquifer. The median change for the confined area of the aquifer was 0.6 feet. From the prestress period (prior to 1965) to 2015, the median water-level change for 34 wells in both the confined and unconfined areas was -13.2 feet; the median water-level changes were -1.7 feet for 16 wells measured in the unconfined areas and -42.3 feet for 18 wells measured in the confined area.Spring flow was measured at four springs in 2014. Flow fluctuated during the

  6. Priority areas for surveillance and prevention of avian influenza during the water-bird migration season in Pakistan

    Directory of Open Access Journals (Sweden)

    Tariq Abbas

    2011-11-01

    Full Text Available Avian influenza viruses may be introduced into domestic poultry through migratory wild birds, particularly from Pakistan, which is situated across the migratory Indus flyway and holds more than 225 wetlands. To answer the question which areas should be given priority in surveillance and prevention with respect to notifiable avian influenza during the migratory season, a subset of Asian waterbird census data was reviewed. The dataset contains 535 local sites and available counts of waterbirds reported from 1987 to 2007. However, as the majority of the sites are not counted regularly gaps in data matrix appeared. The coordinates of 270 known sites completely fitted the administrative boundaries of the country. These coordinates were geo-processed with polygons of water-bodies and a raster map of predicted poultry density. Pixels representing the estimated number of poultry per km2 were found within a 3 to 9 km range of the census sites (or water-bodies in their proximity. The coordinates were also used to map the maximum reported counts of waterbirds and local clusters of under-sampled sites. A retrospective case-series analysis of previous outbreaks (2006-2008 of influenza A virus, subtype H5N1 was performed, which revealed that 64% of outbreaks, reported to Office International des Epizooties, the World Organization for Animal Health, occurred during the migratory period. This paper highlights the potential use and limitations of the Asian waterbirds census data in the context of avian influenza. The proposed methodology may be used to prioritize districts for surveillance and economize prevention measures provided better data are generated in future.

  7. Trends in Surface Water Chemistry in Acidified Areas in Europe and North America from 1990 to 2008

    Science.gov (United States)

    Acidification of lakes and rivers is still an environmental concern despite reduced emissions of acidifying compounds. We analyzed trends in surface water chemistry of 173 acid-sensitive sites from 12 regions in Europe and North America. In 11 of 12 regions, non-marine sulphate (...

  8. Variation in chemistry of stream water and bulk deposition across the Hubbard Brook Valley, New Hampshire, USA

    Science.gov (United States)

    Gene E. Likens; Donald C. Buso; James W. Hornbeck

    2002-01-01

    Chemistry and volume of precipitation and stream water have been measured in south-facing watersheds of the Hubbard Brook Experimental Forest (HBEF), continuously for 37 years. These long-term data have provided important insights into the bio-geochemistry of these watershed ecosystems and the region (e.g. LIKENS & BORMANN 1995).

  9. An Introduction to Boiler Water Chemistry for the Marine Engineer: A Text of Audio-Tutorial Instruction.

    Science.gov (United States)

    Schlenker, Richard M.; And Others

    Presented is a manuscript for an introductory boiler water chemistry course for marine engineer education. The course is modular, self-paced, audio-tutorial, contract graded and combined lecture-laboratory instructed. Lectures are presented to students individually via audio-tapes and 35 mm slides. The course consists of a total of 17 modules -…

  10. Influence of bedrock geology on water chemistry of slope wetlands and headwater streams in the southern Rocky Mountains

    Science.gov (United States)

    Monique LaPerriere Nelson; Charles C. Rhoades; Kathleen A. Dwire

    2011-01-01

    We characterized the water chemistry of nine slope wetlands and adjacent headwater streams in Colorado subalpine forests and compared sites in basins formed on crystalline bedrock with those formed in basins with a mixture of crystalline and sedimentary bedrock. The pH, Ca2+, Mg2+, NH4 +, acid neutralizing capacity, and electrical conductivity of wetland porewater and...

  11. The Effects of Classic and Web-Designed Conceptual Change Texts on the Subject of Water Chemistry

    Science.gov (United States)

    Tas, Erol; Gülen, Salih; Öner, Zeynep; Özyürek, Cengiz

    2015-01-01

    The purpose of this study is to research the effects of traditional and web-assisted conceptual change texts for the subject of water chemistry on the success, conceptual errors and permanent learning of students. A total of 37 8th graders in a secondary school of Samsun participated in this study which had a random experimental design with…

  12. Evolution of the chemistry of Fe bearing waters during CO2 degassing

    Science.gov (United States)

    Geroni, J.N.; Cravotta, C.A.; Sapsford, D.J.

    2012-01-01

    The rates of Fe(II) oxidation and precipitation from groundwater are highly pH dependent. Elevated levels of dissolved CO2 can depress pH and cause difficulty in removing dissolved Fe and associated metals during treatment of ferruginous water. This paper demonstrates interdependent changes in pH, dissolved inorganic C species, and Fe(II) oxidation rates that occur as a result of the removal (degassing) of CO2 during aeration of waters discharged from abandoned coal mines. The results of field monitoring of aeration cascades at a treatment facility as well as batchwise aeration experiments conducted using net alkaline and net acidic waters in the UK are combined with geochemical modelling to demonstrate the spatial and temporal evolution of the discharge water chemistry. The aeration cascades removed approximately 67% of the dissolved CO2 initially present but varying the design did not affect the concentration of Fe(II) leaving the treatment ponds. Continued removal of the residual CO2 by mechanical aeration increased pH by as much as 2 units and resulted in large increases in the rates of Fe(II) oxidation and precipitation. Effective exsolution of CO2 led to a reduction in the required lime dose for removal of remaining Fe(II), a very important factor with regard to increasing the sustainability of treatment practices. An important ancillary finding for passive treatment is that varying the design of the cascades had little impact on the rate of CO2 removal at the flow rates measured.

  13. Ground Water Chemistry Changes before Major Earthquakes and Possible Effects on Animals

    Directory of Open Access Journals (Sweden)

    Friedemann T. Freund

    2011-06-01

    Full Text Available Prior to major earthquakes many changes in the environment have been documented. Though often subtle and fleeting, these changes are noticeable at the land surface, in water, in the air, and in the ionosphere. Key to understanding these diverse pre-earthquake phenomena has been the discovery that, when tectonic stresses build up in the Earth’s crust, highly mobile electronic charge carriers are activated. These charge carriers are defect electrons on the oxygen anion sublattice of silicate minerals, known as positive holes, chemically equivalent to O– in a matrix of O2–. They are remarkable inasmuch as they can flow out of the stressed rock volume and spread into the surrounding unstressed rocks. Travelling fast and far the positive holes cause a range of follow-on reactions when they arrive at the Earth’s surface, where they cause air ionization, injecting massive amounts of primarily positive air ions into the lower atmosphere. When they arrive at the rock-water interface, they act as •O radicals, oxidizing water to hydrogen peroxide. Other reactions at the rock-water interface include the oxidation or partial oxidation of dissolved organic compounds, leading to changes of their fluorescence spectra. Some compounds thus formed may be irritants or toxins to certain species of animals. Common toads, Bufo bufo, were observed to exhibit a highly unusual behavior prior to a M6.3 earthquake that hit L’Aquila, Italy, on April 06, 2009: a few days before the seismic event the toads suddenly disappeared from their breeding site in a small lake about 75 km from the epicenter and did not return until after the aftershock series. In this paper we discuss potential changes in groundwater chemistry prior to seismic events and their possible effects on animals.

  14. Ground water chemistry changes before major earthquakes and possible effects on animals.

    Science.gov (United States)

    Grant, Rachel A; Halliday, Tim; Balderer, Werner P; Leuenberger, Fanny; Newcomer, Michelle; Cyr, Gary; Freund, Friedemann T

    2011-06-01

    Prior to major earthquakes many changes in the environment have been documented. Though often subtle and fleeting, these changes are noticeable at the land surface, in water, in the air, and in the ionosphere. Key to understanding these diverse pre-earthquake phenomena has been the discovery that, when tectonic stresses build up in the Earth's crust, highly mobile electronic charge carriers are activated. These charge carriers are defect electrons on the oxygen anion sublattice of silicate minerals, known as positive holes, chemically equivalent to O- in a matrix of O2-. They are remarkable inasmuch as they can flow out of the stressed rock volume and spread into the surrounding unstressed rocks. Travelling fast and far the positive holes cause a range of follow-on reactions when they arrive at the Earth's surface, where they cause air ionization, injecting massive amounts of primarily positive air ions into the lower atmosphere. When they arrive at the rock-water interface, they act as •O radicals, oxidizing water to hydrogen peroxide. Other reactions at the rock-water interface include the oxidation or partial oxidation of dissolved organic compounds, leading to changes of their fluorescence spectra. Some compounds thus formed may be irritants or toxins to certain species of animals. Common toads, Bufo bufo, were observed to exhibit a highly unusual behavior prior to a M6.3 earthquake that hit L'Aquila, Italy, on April 06, 2009: a few days before the seismic event the toads suddenly disappeared from their breeding site in a small lake about 75 km from the epicenter and did not return until after the aftershock series. In this paper we discuss potential changes in groundwater chemistry prior to seismic events and their possible effects on animals.

  15. Water-soluble chemistry and weathering characteristics of some tills in Western Dronning Maud Land, Antarctica

    Directory of Open Access Journals (Sweden)

    Lintinen, P.

    1997-12-01

    Full Text Available The water-soluble chemistry and weathering characteristics of tills were studied on three nunataks with differing bedrock characteristics in the Vestfjella and Heimefrontfjella areas of the Western Dronning Maud Land, Antarctica. The chemical analyses were performed using ion chromatography and ICP-AES. The relative weathering characteristics of the till surface boulders was assessed in study locations. No colour differences were observed in test pits dug in Basen and Utpostane nunataks at Vestfjella, whereas the till in Mygehenget nunatak at Heimefrontfjella has a pronounced soil profile in which the surface part has a banded rusty brown and light-coloured accumulations. The highest concentrations of readily soluble ions were recorded in the Mygehenget samples characterized by high (SO42- (5800-39000 ppm and Mg concentrations (540-6000 ppm, while the Basen samples had the highest concentrations of Fe2+(23-390 ppm, Al3+ (60-1000 ppm and Si4+ (23-1700 ppm and the Utpostane samples the lowest ones. The SO4/Na+, Na+/CI- and Mg2+/Na+ ratios for the samples differ markedly from those typically encountered in sea water. The presence of the highest concentrations of many of the analysed ions in the Mygehenget soil samples is in line with the advanced weathering of the surface boulders. The high Fe2+ , Si4+ and Al3+ concentrations in the Basen samples may be attributable to the weathering of olivine alteration products.

  16. Investigation into the effect of water chemistry on corrosion product formation in areas of accelerated flow

    Science.gov (United States)

    McGrady, John; Scenini, Fabio; Duff, Jonathan; Stevens, Nicholas; Cassineri, Stefano; Curioni, Michele; Banks, Andrew

    2017-09-01

    The deposition of CRUD (Chalk River Unidentified Deposit) in the primary circuit of a Pressurised Water Reactor (PWR) is known to preferentially occur in regions of the circuit where flow acceleration of coolant occurs. A micro-fluidic flow cell was used to recreate accelerated flow under simulated PWR conditions, by flowing water through a disc with a central micro-orifice. CRUD deposition was reproduced on the disc, and CRUD Build-Up Rates (BUR) in various regions of the disc were analysed. The effect of the local environment on BUR was investigated. In particular, the effect of flow velocity, specimen material and Fe concentration were considered. The morphology and composition of the deposits were analysed with respect to experimental conditions. The BUR of CRUD was found to be sensitive to flow velocity and Fe concentration, suggesting that mass transfer is an important factor. The morphology of the deposit was affected by the specimen material indicating a dependence on surface/particle electrostatics meaning surface chemistry plays an important role in deposition. The preferential deposition of CRUD in accelerated flow regions due to electrokinetic effects was observed and it was shown that higher Fe concentrations in solution increased BURs within the orifice whereas increased flow velocity reduced BURs.

  17. Stream water chemistry in the arsenic-contaminated Baccu Locci mine watershed (Sardinia, Italy) after remediation.

    Science.gov (United States)

    Ardau, Carla; Podda, Francesca; Da Pelo, Stefania; Frau, Franco

    2013-11-01

    The abandoned Pb-As Baccu Locci mine represents the first and only case of mine site remediation in Sardinia, Italy. Arsenic is the most relevant environmental concern in the Baccu Locci stream watershed, with concentrations in surface waters up to and sometimes over 1 mg/L. The main remediation action consisted in creation of a "storage site", for the collection of contaminated materials from different waste-rock dumps and most of tailings piles occurring along the Baccu Locci stream. This paper reports preliminary results on the level of contamination in the Baccu Locci stream after the completion of remediation measures. Post-remediation stream water chemistry has not substantially changed compared to the pre-remediation situation. In particular, dissolved As maintains an increasing trend along the Baccu Locci stream, with a concentration of about 400 μg/L measured at a distance of 7 km from the storage site. Future monitoring will provide fundamental information on the effectiveness of remediation actions conducted and their applicability to other mine sites in Sardinia. At the stage of mine site characterisation of future remediation plans, it is recommended to pay more attention to the understanding of mineralogical and geochemical processes responsible for pollution. Moreover, mixing of materials with different composition and reactivity in a storage site should require careful consideration and long-term leaching tests.

  18. Host-guest chemistry with water-soluble gold nanoparticle supraspheres

    Science.gov (United States)

    Wang, Yizhan; Zeiri, Offer; Raula, Manoj; Le Ouay, Benjamin; Stellacci, Francesco; Weinstock, Ira A.

    2017-02-01

    The uptake of molecular guests, a hallmark of the supramolecular chemistry of cages and containers, has yet to be documented for soluble assemblies of metal nanoparticles. Here we demonstrate that gold nanoparticle-based supraspheres serve as a host for the hydrophobic uptake, transport and subsequent release of over two million organic guests, exceeding by five orders of magnitude the capacities of individual supramolecular cages or containers and rivalling those of zeolites and metal-organic frameworks on a mass-per-volume basis. The supraspheres are prepared in water by adding hexanethiol to polyoxometalate-protected 4 nm gold nanoparticles. Each 200 nm assembly contains hydrophobic cavities between the estimated 27,400 gold building blocks that are connected to one another by nanometre-sized pores. This gives a percolated network that effectively absorbs large numbers of molecules from water, including 600,000, 2,100,000 and 2,600,000 molecules (35, 190 and 234 g l-1) of para-dichorobenzene, bisphenol A and trinitrotoluene, respectively.

  19. Interactions between hydrology and water chemistry shape bacterioplankton biogeography across boreal freshwater networks.

    Science.gov (United States)

    Niño-García, Juan Pablo; Ruiz-González, Clara; Del Giorgio, Paul A

    2016-07-01

    Disentangling the mechanisms shaping bacterioplankton communities across freshwater ecosystems requires considering a hydrologic dimension that can influence both dispersal and local sorting, but how the environment and hydrology interact to shape the biogeography of freshwater bacterioplankton over large spatial scales remains unexplored. Using Illumina sequencing of the 16S ribosomal RNA gene, we investigate the large-scale spatial patterns of bacterioplankton across 386 freshwater systems from seven distinct regions in boreal Québec. We show that both hydrology and local water chemistry (mostly pH) interact to shape a sequential structuring of communities from highly diverse assemblages in headwater streams toward larger rivers and lakes dominated by fewer taxa. Increases in water residence time along the hydrologic continuum were accompanied by major losses of bacterial richness and by an increased differentiation of communities driven by local conditions (pH and other related variables). This suggests that hydrology and network position modulate the relative role of environmental sorting and mass effects on community assembly by determining both the time frame for bacterial growth and the composition of the immigrant pool. The apparent low dispersal limitation (that is, the lack of influence of geographic distance on the spatial patterns observed at the taxonomic resolution used) suggests that these boreal bacterioplankton communities derive from a shared bacterial pool that enters the networks through the smallest streams, largely dominated by mass effects, and that is increasingly subjected to local sorting of species during transit along the hydrologic continuum.

  20. Effect of long-term application of biosolids for land reclamation on surface water chemistry.

    Science.gov (United States)

    Tian, G; Granato, T C; Pietz, R I; Carlson, C R; Abedin, Z

    2006-01-01

    Biosolids are known to have a potential to restore degraded land, but the long-term impacts of this practice on the environment, including water quality, still need to be evaluated. The surface water chemistry (NO3-, NH4+, and total P, Cd, Cu, and Hg) was monitored for 31 yr from 1972 to 2002 in a 6000-ha watershed at Fulton County, Illinois, where the Metropolitan Water Reclamation District of Greater Chicago was restoring the productivity of strip-mined land using biosolids. The mean cumulative loading rates during the past 31 yr were 875 dry Mg ha(-1) for 1120-ha fields in the biosolids-amended watershed and 4.3 dry Mg ha(-1) for the 670-ha fields in the control watershed. Biosolids were injected into mine spoil fields as liquid fertilizer from 1972 to 1985, and incorporated as dewatered cake from 1980 to 1996 and air-dried solids from 1987 to 2002. The mean annual loadings of nutrients and trace elements from biosolids in 1 ha were 735 kg N, 530 kg P, 4.5 kg Cd, 30.7 kg Cu, and 0.11 kg Hg in the fields of the biosolids-amended watershed, and negligible in the fields of the control watershed. Sampling of surface water was conducted monthly in the 1970s, and three times per year in the 1980s and 1990s. The water samples were collected from 12 reservoirs and 2 creeks receiving drainage from the fields in the control watershed, and 8 reservoirs and 4 creeks associated with the fields in the biosolids-amended watershed for the analysis of NO3- -N (including NO2- N), NH4+-N, and total P, Cd, Cu, and Hg. Compared to the control (0.18 mg L(-1)), surface water NO3- -N in the biosolids-amended watershed (2.23 mg L(-1)) was consistently higher; however, it was still below the Illinois limit of 10 mg L(-1) for public and food-processing water supplies. Biosolids applications had a significant effect on mean concentrations of ammonium N (0.11 mg L(-1) for control and 0.24 mg L(-1) for biosolids) and total P (0.10 mg L(-1) for control and 0.16 mg L(-1) for biosolids) in

  1. Standard Practice for Analysis and Interpretation of Light-Water Reactor Surveillance Results, E706(IA)

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2001-01-01

    1.1 This practice covers the methodology, summarized in Annex A1, to be used in the analysis and interpretation of neutron exposure data obtained from LWR pressure vessel surveillance programs; and, based on the results of that analysis, establishes a formalism to be used to evaluate present and future condition of the pressure vessel and its support structures (1-70). 1.2 This practice relies on, and ties together, the application of several supporting ASTM standard practices, guides, and methods (see Master Matrix E 706) (1, 5, 13, 48, 49). In order to make this practice at least partially self-contained, a moderate amount of discussion is provided in areas relating to ASTM and other documents. Support subject areas that are discussed include reactor physics calculations, dosimeter selection and analysis, and exposure units. Note 1—(Figure 1 is deleted in the latest update. The user is refered to Master Matrix E 706 for the latest figure of the standards interconnectivity). 1.3 This practice is restri...

  2. Effect of water stage and tree stand composition on spatiotemporal differentiation of spring water chemistry draining Carpathian flysch slopes (Gorce Mts).

    Science.gov (United States)

    Jasik, Michał; Małek, Stanisław; Żelazny, Mirosław

    2017-12-01

    The purpose of this study was to identify the factors affecting spring water chemistry in different tree stands and to measure the influence of water stage on the physicochemical parameters of spring waters in a small Carpathian catchment. Water samples were collected three times per year at various stages of the water: after the spring thaw, after a period of heavy rain and after a dry period in 2011 and 2012. Water samples were left in the laboratory to reach room temperature (19-20°C) and analyzed for EC (reference T=25°C) and pH. After filtration through 0.45μm PTFE syringe filters, the water samples were analyzed by means of ion chromatography using a DIONEX ICS 5000 unit. The following ions were analyzed: Ca2+, Mg2+, Na+, K+, HCO3-, SO42-, Cl-, and NO3-. Multivariate analysis (PCA) allowed the identification of two factors of spring water chemistry: factor 1, water stage and factor 2 tree stand composition. Seasonal variation of spring water chemistry showed that, higher pH values and mineralization as well as higher concentrations of Ca2+ and Mg2+ were measured during low water stage periods while lower EC and pH values were noted after spring snowmelt and rainfall, when higher concentrations of NO3- and SO42- were also found. Higher concentrations of Ca2+ and Mg2+ and higher pH of spring waters located in beech-fir stands and in those mixed with a large proportion of beech as well as a lower concentration of Ca2+, Mg2+ and HCO3-, pH, conductivity and mineralization of these spring waters, in which the alimentation areas were covered by upper subalpine spruce stands were noted. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Variability of Water Chemistry in Tundra Lakes, Petuniabukta Coast, Central Spitsbergen, Svalbard

    Science.gov (United States)

    Mazurek, Małgorzata; Paluszkiewicz, Renata; Rachlewicz, Grzegorz; Zwoliński, Zbigniew

    2012-01-01

    Samples of water from small tundra lakes located on raised marine terraces on the eastern coast of Petuniabukta (Ebbadalen, Central Spitsbergen) were examined to assess the changes in water chemistry that had occurred during the summer seasons of 2001–2003 and 2006. The unique environmental conditions of the study region include the predominance of sedimentary carbonate and sulphate rocks, low precipitation values, and an active permafrost layer with a maximum thickness of 1.2 m. The average specific electric conductivity (EC) values for the three summer seasons in the four lakes ranged from 242 to 398 μS cm−1. The highest EC values were observed when the air temperature decreased and an ice cover formed (cryochemical effects). The ion composition was dominated by calcium (50.7 to 86.6%), bicarbonates (39.5 to 86.4%), and sulphate anions. The high concentrations of HCO3 −, SO4 2−, and Ca2+ ions were attributed to the composition of the bedrock, which mainly consists of gypsum and anhydrite. The average proportion of marine components in the total load found in the Ebbadalen tundra lake waters was estimated to be 8.1%. Precipitation supplies sulphates (as much as 69–81%) and chlorides (14–36%) of nonsea origin. The chief source of these compounds may be contamination from the town of Longyearbyen. Most ions originate in the crust, the active layer of permafrost, but some are atmospheric in origin and are either transported or generated in biochemical processes. The concentrations of most components tend to increase during the summer months, reaching a maximum during freezing and partially precipitating onto the bottom sediments. PMID:22654629

  4. Pore water chemistry reveals gradients in mineral transformation across a model basaltic hillslope

    Science.gov (United States)

    Pohlmann, Michael; Dontsova, Katerina; Root, Robert; Ruiz, Joaquin; Troch, Peter; Chorover, Jon

    2016-06-01

    The extent of weathering incongruency during soil formation from rock controls local carbon and nutrient cycling in ecosystems, as well as the evolution of hydrologic flow paths. Prior studies of basalt weathering, including those that have quantified the dynamics of well-mixed, bench-scale laboratory reactors or characterized the structure and integrated response of field systems, indicate a strong influence of system scale on weathering rate and trajectory. For example, integrated catchment response tends to produce lower weathering rates than do well mixed reactors, but the mechanisms underlying these disparities remain unclear. Here we present pore water geochemistry and physical sensor data gathered during two controlled rainfall-runoff events on a large-scale convergent model hillslope mantled with 1 m uniform depth of granular basaltic porous media. The dense sampler and sensor array (1488 samplers and sensors embedded in 330 m3 of basalt) showed that rainfall-induced dissolution of basaltic glass produced supersaturation of pore waters with respect to multiple secondary solids including allophane, gibbsite, ferrihydrite, birnessite and calcite. The spatial distribution of saturation state was heterogeneous, suggesting an accumulation of solutes leading to precipitation of secondary solids along hydrologic flow paths. Rapid dissolution of primary silicates was widespread throughout the entire hillslope, irrespective of up-gradient flowpath length. However, coherent spatial variations in solution chemistry and saturation indices were observed in depth profiles and between distinct topographic regions of the hillslope. Colloids (110-2000 nm) enriched in iron (Fe), aluminum (Al), and phosphorus (P) were mobile in soil pore waters.

  5. Variability of Water Chemistry in Tundra Lakes, Petuniabukta Coast, Central Spitsbergen, Svalbard

    Directory of Open Access Journals (Sweden)

    Małgorzata Mazurek

    2012-01-01

    Full Text Available Samples of water from small tundra lakes located on raised marine terraces on the eastern coast of Petuniabukta (Ebbadalen, Central Spitsbergen were examined to assess the changes in water chemistry that had occurred during the summer seasons of 2001–2003 and 2006. The unique environmental conditions of the study region include the predominance of sedimentary carbonate and sulphate rocks, low precipitation values, and an active permafrost layer with a maximum thickness of 1.2 m. The average specific electric conductivity (EC values for the three summer seasons in the four lakes ranged from 242 to 398 μS cm−1. The highest EC values were observed when the air temperature decreased and an ice cover formed (cryochemical effects. The ion composition was dominated by calcium (50.7 to 86.6%, bicarbonates (39.5 to 86.4%, and sulphate anions. The high concentrations of HCO3−, SO42−, and Ca2+ ions were attributed to the composition of the bedrock, which mainly consists of gypsum and anhydrite. The average proportion of marine components in the total load found in the Ebbadalen tundra lake waters was estimated to be 8.1%. Precipitation supplies sulphates (as much as 69–81% and chlorides (14–36% of nonsea origin. The chief source of these compounds may be contamination from the town of Longyearbyen. Most ions originate in the crust, the active layer of permafrost, but some are atmospheric in origin and are either transported or generated in biochemical processes. The concentrations of most components tend to increase during the summer months, reaching a maximum during freezing and partially precipitating onto the bottom sediments.

  6. Tundra fire alters stream water chemistry and benthic invertebrate communities, North Slope, Alaska

    Science.gov (United States)

    Allen, A. R.; Bowden, W. B.; Kling, G. W.; Schuett, E.; Kostrzewski, J. M.; Kolden Abatzoglou, C.; Findlay, R. H.

    2010-12-01

    Increased fire frequency and severity are potentially important consequences of climate change in high latitude ecosystems. The 2007 Anaktuvuk River fire, which burned from July until October, is the largest recorded tundra fire from Alaska's north slope (≈1,000 km2). The immediate effects of wildfire on water chemistry and biotic assemblages in tundra streams are heretofore unknown. We hypothesized that a tundra fire would increase inorganic nutrient inputs to P-limited tundra streams, increasing primary production and altering benthic macroinvertebrate community structure. We examined linkages among: 1) percentage of riparian zone and overall watershed vegetation burned, 2) physical, chemical and biological stream characteristics, and 3) macroinvertebrate communities in streams draining burned and unburned watersheds during the summers of 2008 and 2009. Streams in burned watersheds contained higher mean concentrations of soluble reactive phosphorus (SRP), ammonium (NH4+), and dissolved organic carbon (DOC). In contrast, stream nitrate (NO3-) concentrations were lower in burned watersheds. The net result was that the tundra fire did not affect concentrations of dissolved inorganic nitrogen (NH4+ + NO3-). In spite of increased SRP, benthic chlorophyll-a biomass was not elevated. Macroinvertebrate abundances were 1.5 times higher in streams draining burned watersheds; Chironomidae midges, Nematodes, and Nemoura stoneflies showed the greatest increases in abundance. Multivariate multiple regression identified environmental parameters associated with the observed changes in the macroinvertebrate communities. Since we identified stream latitude as a significant predictor variable, latitude was included in the model as a covariate. After removing the variation associated with latitude, 67.3 % of the variance in macroinvertebrate community structure was explained by a subset of 7 predictor variables; DOC, conductivity, mean temperature, NO3-, mean discharge, SRP and NH

  7. Surveillance Culture

    DEFF Research Database (Denmark)

    2017-01-01

    What does it mean to live in a world full of surveillance? In this documentary film, we take a look at everyday life in Denmark and how surveillance technologies and practices influence our norms and social behaviour....

  8. Military surveillance

    OpenAIRE

    Wilson, Dean

    2012-01-01

    Military surveillance offers a crucial entry point into the study of surveillance. Historically, the importance of military organizations in state formation meant that many techniques of surveillance that would later migrate into the civilian sphere would bear the imprint of military origins. Moreover, military campaigns were instrumental in developing forms of discipline, communication and surveillance that were to have far-reaching implications for whole societies. Thus, both technologicall...

  9. Plasma Discharges in Gas Bubbles in Liquid Water: Breakdown Mechanisms and Resultant Chemistry

    Science.gov (United States)

    Gucker, Sarah M. N.

    The use of atmospheric pressure plasmas in gases and liquids for purification of liquids has been investigated by numerous researchers, and is highly attractive due to their strong potential as a disinfectant and sterilizer. However, the fundamental understanding of plasma production in liquid water is still limited. Despite the decades of study dedicated to electrical discharges in liquids, many physical aspects of liquids, such as the high inhomogeneity of liquids, complicate analyses. For example, the complex nonlinearities of the fluid have intricate effects on the electric field of the propagating streamer. Additionally, the liquid material itself can vaporize, leading to discontinuous liquid-vapor boundaries. Both can and do often lead to notable hydrodynamic effects. The chemistry of these high voltage discharges on liquid media can have circular effects, with the produced species having influence on future discharges. Two notable examples include an increase in liquid conductivity via charged species production, which affects the discharge. A second, more complicated scenario seen in some liquids (such as water) is the doubling or tripling of molecular density for a few molecule layers around a high voltage electrode. These complexities require technological advancements in optical diagnostics that have only recently come into being. This dissertation investigates several aspects of electrical discharges in gas bubbles in liquids. Two primary experimental configurations are investigated: the first allows for single bubble analysis through the use of an acoustic trap. Electrodes may be brought in around the bubble to allow for plasma formation without physically touching the bubble. The second experiment investigates the resulting liquid phase chemistry that is driven by the discharge. This is done through a dielectric barrier discharge with a central high voltage surrounded by a quartz discharge tube with a coil ground electrode on the outside. The plasma

  10. Hospitalization records as a tool for evaluating performance of food- and water-borne disease surveillance systems: a Massachusetts case study.

    Directory of Open Access Journals (Sweden)

    Siobhan M Mor

    Full Text Available We outline a framework for evaluating food- and water-borne surveillance systems using hospitalization records, and demonstrate the approach using data on salmonellosis, campylobacteriosis and giardiasis in persons aged ≥65 years in Massachusetts. For each infection, and for each reporting jurisdiction, we generated smoothed standardized morbidity ratios (SMR and surveillance to hospitalization ratios (SHR by comparing observed surveillance counts with expected values or the number of hospitalized cases, respectively. We examined the spatial distribution of SHR and related this to the mean for the entire state. Through this approach municipalities that deviated from the typical experience were identified and suspected of under-reporting. Regression analysis revealed that SHR was a significant predictor of SMR, after adjusting for population age-structure. This confirms that the spatial "signal" depicted by surveillance is in part influenced by inconsistent testing and reporting practices since municipalities that reported fewer cases relative to the number of hospitalizations had a lower relative risk (as estimated by SMR. Periodic assessment of SHR has potential in assessing the performance of surveillance systems.

  11. Hospitalization records as a tool for evaluating performance of food- and water-borne disease surveillance systems: a Massachusetts case study.

    Science.gov (United States)

    Mor, Siobhan M; DeMaria, Alfred; Naumova, Elena N

    2014-01-01

    We outline a framework for evaluating food- and water-borne surveillance systems using hospitalization records, and demonstrate the approach using data on salmonellosis, campylobacteriosis and giardiasis in persons aged ≥65 years in Massachusetts. For each infection, and for each reporting jurisdiction, we generated smoothed standardized morbidity ratios (SMR) and surveillance to hospitalization ratios (SHR) by comparing observed surveillance counts with expected values or the number of hospitalized cases, respectively. We examined the spatial distribution of SHR and related this to the mean for the entire state. Through this approach municipalities that deviated from the typical experience were identified and suspected of under-reporting. Regression analysis revealed that SHR was a significant predictor of SMR, after adjusting for population age-structure. This confirms that the spatial "signal" depicted by surveillance is in part influenced by inconsistent testing and reporting practices since municipalities that reported fewer cases relative to the number of hospitalizations had a lower relative risk (as estimated by SMR). Periodic assessment of SHR has potential in assessing the performance of surveillance systems.

  12. Microbial metabolism alters pore water chemistry and increases consolidation of oil sands tailings.

    Science.gov (United States)

    Arkell, Nicholas; Kuznetsov, Petr; Kuznetsova, Alsu; Foght, Julia M; Siddique, Tariq

    2015-01-01

    Tailings produced during bitumen extraction from surface-mined oil sands ores (tar sands) comprise an aqueous suspension of clay particles that remain dispersed for decades in tailings ponds. Slow consolidation of the clays hinders water recovery for reuse and retards volume reduction, thereby increasing the environmental footprint of tailings ponds. We investigated mechanisms of tailings consolidation and revealed that indigenous anaerobic microorganisms altered porewater chemistry by producing CO and CH during metabolism of acetate added as a labile carbon amendment. Entrapped biogenic CO decreased tailings pH, thereby increasing calcium (Ca) and magnesium (Mg) cations and bicarbonate (HCO) concentrations in the porewater through dissolution of carbonate minerals. Soluble ions increased the porewater ionic strength, which, with higher exchangeable Ca and Mg, decreased the diffuse double layer of clays and increased consolidation of tailings compared with unamended tailings in which little microbial activity was observed. These results are relevant to effective tailings pond management strategies. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  13. Mineralogy and pore water chemistry of a boiler ash from a MSW fluidized-bed incinerator.

    Science.gov (United States)

    Bodénan, F; Guyonnet, D; Piantone, P; Blanc, P

    2010-07-01

    This paper presents an investigation of the mineralogy and pore water chemistry of a boiler ash sampled from a municipal solid waste fluidized-bed incinerator, subject to 18 months of dynamic leaching in a large percolation column experiment. A particular focus is on the redox behaviour of Cr(VI) in relation to metal aluminium Al(0), as chromium may represent an environmental or health hazard. The leaching behaviour and interaction between Cr(VI) and Al(0) are interpreted on the basis of mineralogical evolutions observed over the 18-month period and of saturation indices calculated with the geochemical code PhreeqC and reviewed thermodynamic data. Results of mineralogical analyses show in particular the alteration of mineral phases during leaching (e.g. quartz and metal aluminium grains), while geochemical calculations suggest equilibria of percolating fluids with respect to specific mineral phases (e.g. monohydrocalcite and aluminium hydroxide). The combination of leaching data on a large scale and mineralogical analyses document the coupled leaching behaviour of aluminium and chromium, with chromium appearing in the pore fluids in its hexavalent and mobile state once metal aluminium is no longer available for chromium reduction. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

  14. Degradation of Environmental Contaminants with Water-Soluble Cobalt Catalysts: An Integrative Inorganic Chemistry Investigation

    Science.gov (United States)

    Evans, Alexandra L.; Messersmith, Reid E.; Green, David B.; Fritsch, Joseph M.

    2011-01-01

    We present an integrative laboratory investigation incorporating skills from inorganic chemistry, analytical instrumentation, and physical chemistry applied to a laboratory-scale model of the environmental problem of chlorinated ethylenes in groundwater. Perchloroethylene (C[subscript 2]Cl[subscript 4], PCE) a common dry cleaning solvent,…

  15. Water chemistry of tundra lakes in the periglacial zone of the Bellsund Fiord (Svalbard) in the summer of 2013.

    Science.gov (United States)

    Szumińska, Danuta; Szopińska, Małgorzata; Lehmann-Konera, Sara; Franczak, Łukasz; Kociuba, Waldemar; Chmiel, Stanisław; Kalinowski, Paweł; Polkowska, Żaneta

    2018-05-15

    Climate changes observed in the Arctic (e.g. permafrost degradation, glacier retreat) may have significant influence on sensitive polar wetlands. The main objectives of this paper are defining chemical features of water within six small arctic lakes located in Bellsund (Svalbard) in the area of continuous permafrost occurrence. The unique environmental conditions of the study area offer an opportunity to observe phenomena influencing water chemistry, such as: chemical weathering, permafrost thawing, marine aerosols, atmospheric deposition and biological inputs. In the water samples collected during the summer 2013, detailed tundra lake water chemistry characteristics regarding ions, trace elements, pH and specific electrolytic conductivity (SEC 25 ) analysis were determined. Moreover, water chemistry of the studied lakes was compared to the water samples from the Tyvjobekken Creek and precipitation water samples. As a final step of data analysis, Principal Component Analysis (PCA) was performed. Detailed chemical analysis allowed us to conclude what follows: (1) Ca 2+ , Mg 2+ , SO 4 2- , Sr are of geogenic origin, (2) NO 3 - present in tundra lakes and the Tyvjobekken Creek water samples (ranging from 0.31 to 1.69mgL - 1 and from 0.25 to 1.58mgL - 1 respectively) may be of mixed origin, i.e. from biological processes and permafrost thawing, (3) high contribution of non-sea-salt SO 4 2- >80% in majority of studied samples indicate considerable inflow of sulphate-rich air to the study area, (4) high content of chlorides in tundra lakes (range: 25.6-32.0% meqL - 1 ) indicates marine aerosol influence, (5) PCA result shows that atmospheric transport may constitute a source of Mn, Co, Ni, Cu, Ga, Ba and Cd. However, further detailed inter-season and multi-seasonal study of tundra lakes in the Arctic are recommended. Especially in terms of detailed differentiation of sources influence (atmospheric transport vs. permafrost degradation). Copyright © 2017 Elsevier B.V. All

  16. A teacher as researcher study of high school chemistry student ideas about the particulate nature of water

    Science.gov (United States)

    Kruckeberg, Robert Fredrick

    The objective of this study was to advance the pedagogical content knowledge base for teaching high school chemistry by conducting qualitative research on students' scientific understanding of water prior to, during, and after formal instruction on the particulate nature of matter. The study was conducted within a constructivist theoretical framework, with an emphasis on John Dewey's pragmatic social constructivism. The teacher-as-researcher conducted three sets of clinical interviews based on three related contexts: representation of water in the liquid state, interaction of water with a solute, and water vaporizing and condensing. Interviews and class work were analyzed to determine the extent to which students used the particulate nature of matter to reorganize their understanding of water. Findings present student responses in terms of four different aspects of the particulate model, where students frequently emphasized certain aspects of the model to the exclusion of others. These aspects were identified as "Simple Particles," "Mechanical Kinetic," "Differential Chemical", and "Electrostatic Interactive." Students exhibited significant difficulty in extending micro-mechanical aspects of the model into an electrostatic-interactive understanding of water. Applications of the particulate model were often highly context dependent. Students showed a variety of unique, alternative interpretations of the particulate nature of water that were supported by rich qualitative interview responses. Student difficulties understanding the particulate nature of water were attributed to alternative conceptions prior to instruction as well as the content and sequencing of the traditional biology-chemistry-physics science curriculum. The study recommends changes in curriculum sequencing, improved instruction in the nature of science and scientific models, and the need for introducing students to ideas in physics, especially electrostatics, prior to the study of introductory

  17. [Surveillance of Oncomelania hupensis snails in Baoying and Gaoyou sections of Li Canal in east route of South-to-North Water Diversion Project].

    Science.gov (United States)

    Li, Wei; Gao, Jin-Bin; Zheng, Bo; Huang, Yi-Xin; Hang, De-Rong; Zhang, Jian-Feng; Lu, Jia-Xiang; He, Yong; Wan, Zhong; Huang, Ya-Ming; Gao, Yang; Zuo, Yin-Ping

    2011-08-01

    To understand the distribution and diffusion of Oncomelania hupensis snails in the Baoying and Gaoyou sections of the Li Canal in the east route of the South-to-North Water Diversion Project. The retrospective survey method was used to investigate the distribution and diffusion of snails in the Baoying and Gaoyou sections of the Li Canal, the conventional survey and the methods of salvage of water and attracting snails were used to detect the distribution of snails in river banks and water. The earliest findings of snails in the Gaoyou section of the Li Canal was in 1955, the northernmost distribution of snails was Dilong ferry at the west dam and east slope of the Li Canal. The dynamic surveillance in the Gaoyou section of the Li Canal from 2001 to 2010 showed that the snail status was of low density and low fluctuation of area, and the distribution range was 119 degrees 24' 36" -119 degrees 25' 34", 32 degrees 48' 30" -32 degrees 54' 05". From 2006 to 2010, the snails were not found by the methods of salvage of water and attracting snails in the surveillance in the Baoying and Gaoyou sections of the Li Canal. So far, there is no evidence showing that the snails spread to northward in the Li Canal, however, it is still necessary to carry out the surveillance of snails and schistosomiasis in the east route of the South-to-North Water Diversion Project.

  18. Surveillance of parasitic Legionella in surface waters by using immunomagnetic separation and amoebae enrichment.

    Science.gov (United States)

    Hsu, Tsui-Kang; Wu, Shu-Fen; Hsu, Bing-Mu; Kao, Po-Min; Tao, Chi-Wei; Shen, Shu-Min; Ji, Wen-Tsai; Huang, Wen-Chien; Fan, Cheng-Wei

    2015-01-01

    Free-living amoebae (FLA) are potential reservoirs of Legionella in aquatic environments. However, the parasitic relationship between various Legionella and amoebae remains unclear. In this study, surface water samples were gathered from two rivers for evaluating parasitic Legionella. Warmer water temperature is critical to the existence of Legionella. This result suggests that amoebae may be helpful in maintaining Legionella in natural environments because warmer temperatures could enhance parasitisation of Legionella in amoebae. We next used immunomagnetic separation (IMS) to identify extracellular Legionella and remove most free Legionella before detecting the parasitic ones in selectively enriched amoebae. Legionella pneumophila was detected in all the approaches, confirming that the pathogen is a facultative amoebae parasite. By contrast, two obligate amoebae parasites, Legionella-like amoebal pathogens (LLAPs) 8 and 9, were detected only in enriched amoebae. However, several uncultured Legionella were detected only in the extracellular samples. Because the presence of potential hosts, namely Vermamoeba vermiformis, Acanthamoeba spp. and Naegleria gruberi, was confirmed in the samples that contained intracellular Legionella, uncultured Legionella may survive independently of amoebae. Immunomagnetic separation and amoebae enrichment may have referential value for detecting parasitic Legionella in surface waters.

  19. Fluorescence spectroscopy for field surveillance of THM formation precursors to increase sustainable drinking water treatment for the water industry

    Science.gov (United States)

    Stutter, Marc; Cooper, Pat; Wyness, Adam; Allan, Richard; Weir, Paul; Frogbrook, Zoe; Haffey, Mark

    2017-04-01

    Our understanding of the composition and diversity of dissolved organic matter (DOM) in natural waters is improving rapidly with techniques such as fluorescence spectroscopy. For the water industry issues of the reaction of DOM and different processes used to reduce microbial contamination in water for public supply are a pressing concern. A range of processes can be used but the common disinfection by free chlorine can react with DOM to produce a group of substances referred to as disinfection by-products (DBPs) that have been linked to health concerns. Hence, management at water treatment works aims to remove DOM prior to the disinfection reaction or change the treatment method. Both are costly financially and in terms of process chemical, such as coagulents that work variably with different DOM forms. Hence, enabling methods of catchment management, which have long been associated with tackling other forms of pollution (e.g. N, P) through source-pathway-receptor concepts, are options for the water industry where catchment raw water source management is a possible sustainable addition to conventional treatment. This presentation looks at the requirements and ongoing work to inform source water management options using bench-top fluorescence excitation-emission spectroscopy and hand-held sensors to detect DBP precursors, namely trihalomethanes (THMs), in complex multi-source environments. We start by introducing the forms of DOM discernible in the fluorescence excitation-emission matrix, how these have been ascribed to different compounds by previous studies and what wavelengths are available for in-situ detection. We then discuss methodology issues for sample storage and standard materials. Then we draw on results from a national set of Scottish catchments and a small catchment study to evaluate relationships between THM compounds from standard assay and GC-MS detection against spectral DOM surrogates, including catchment hydrochemical and spatial data covariates

  20. A biodynamic model predicting waterborne lead bioaccumulation in Gammarus pulex: Influence of water chemistry and in situ validation.

    Science.gov (United States)

    Urien, N; Uher, E; Billoir, E; Geffard, O; Fechner, L C; Lebrun, J D

    2015-08-01

    Metals bioaccumulated in aquatic organisms are considered to be a good indicator of bioavailable metal contamination levels in freshwaters. However, bioaccumulation depends on the metal, the species, and the water chemistry that influences metal bioavailability. In the laboratory, a kinetic model was used to describe waterborne Pb bioaccumulated in Gammarus pulex. Uptake and elimination rate constants were successfully determined and the effect of Ca(2+) on Pb uptake was integrated into the model. Thereafter, accumulated Pb concentrations in organisms were predicted with the model and compared with those measured in native populations from the Seine watershed (France). The predictions had a good agreement with the bioaccumulation levels observed in native gammarids and particularly when the effect of calcium was considered. To conclude, kinetic parameters experimentally derived for Pb in G. pulex are applicable in environmental conditions. Moreover, the consideration of the water's chemistry is crucial for a reliable interpretation of bioaccumulation. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. Water physics and chemistry data from moored current meter and bottle casts in the Coastal Waters of New Jersey as part of the Mesa New York Bight (MESA - NYB) project, 05 November 1973 to 06 June 1974 (NODC Accession 7500931)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Water physics and chemistry data were collected using moored current meter and bottle casts in the Coastal Waters of New Jersey from November 5, 1973 to June 6,...

  2. Water physics and chemistry data from moored current meter and bottle casts in the Coastal Waters of New Jersey as part of the Mesa New York Bight (MESA - NYB) project, 28 April 1977 - 19 October 1977 (NODC Accession 7800053)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Water physics and chemistry data were collected using moored current meter and bottle casts in the Coastal Waters of New Jersey from April 28, 1977 to October 19,...

  3. Water physics and chemistry data from moored current meter and bottle casts in the Coastal Waters of New Jersey as part of the Mesa New York Bight (MESA - NYB) project, 21 May 1963 - 08 July 1975 (NODC Accession 7601561)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Water physics and chemistry data were collected using moored current meter and bottle casts in the Coastal Waters of New Jersey from May 21, 1963 to July 8, 1975....

  4. Vertical-Deformation, Water-Level, Microgravity, Geodetic, Water-Chemistry, and Flow-Rate Data Collected During Injection, Storage, and Recovery Tests at Lancaster, Antelope Valley, California, September 1995 Through September 1998

    National Research Council Canada - National Science Library

    Metzger, Loren F; Ikehara, Marti E; Howle, James F

    2002-01-01

    .... Monitoring networks were established at or in the vicinity of the test site to measure vertical deformation of the aquifer system, water-level fluctuations, land-surface deformation, water chemistry...

  5. Adventures in STEM: Lessons in Water Chemistry From Elementary School to Graduate School

    Science.gov (United States)

    Dittrich, T. M.

    2014-12-01

    I will present the accumulation of over 10 years of experience teaching STEM subjects to students ranging from 1st grade to graduate school. I was fortunate to gain a lot of valuable teaching experience while in graduate school in Boulder, CO and so many of my experiences center on opportunities for connecting with students in the field in CO. 3rd-5th grade field hikes - While helping at Jamestown Elementary School, I led hikes with a 3-5th grade class to an abandoned flourospar mine where the students were able to pick up beautiful purple fluorite crystals from the ground while discussing how mining works. During the hike back, we used field meters to measure the pH and conductivity of the stream and discussed the need to balance society's need for metals with the harmful effects of acid mine drainage. 9th, 10th grade STEM Academy at Skyline High School - During an NSF-sponsored fellowship, I had the opportunity to teach a STEM class to 9th and 10th graders where we used the engineering design process to a) design a tool to help a handicapped 3rd grader use the drinking fountain by herself and b) design a treatment system for cleaning up acid mine drainage. Undergraduate and Graduate Environmental Water Chemistry Field Trip - Students had the opportunity to tour two local mine sites to collect contaminated water that would be used in class for alkalinity titrations and pH, sulfate, and hardness measurements. They also collected water samples upstream and at multiple points downstream of a wastewater treatment plan and measured and graphed the dissolved oxygen "sag" in the river. My main teaching philosophy has two parts: 1) assume the students know nothing and 2) assume the students are even smarter than you think you are. This informs my approach to field trips by always starting from the beginning, but also not oversimplifying the topic. 1st graders on their best day can be very similar to graduate students on their worst.

  6. The effects of season, habitat, hydroperiod and water chemistry on the distribution of turlough aquatic invertebrate communities

    OpenAIRE

    Porst, Gwendolin

    2009-01-01

    PUBLISHED The aim of this study was to investigate the effects of season, habitat, hydroperiod and water chemistry on the distribution of turlough aquatic invertebrate communities. Twenty-two turloughs, selected as representative of geographical distribution and hydrological conditions were included in the study. A comparative study of eight turloughs representing a nutrient gradient determined macroinvertebrate community distinctiveness in a stratified sampling design and related assembla...

  7. Critical Loads of Acid Deposition for Wilderness Lakes in the Sierra Nevada (California) Estimated by the Steady-State Water Chemistry Model

    Science.gov (United States)

    Glenn D. Shaw; Ricardo Cisneros; Donald Schweizer; James O. Sickman; Mark E. Fenn

    2014-01-01

    Major ion chemistry (2000-2009) from 208 lakes (342 sample dates and 600 samples) in class I and II wilderness areas of the Sierra Nevada was used in the Steady-State Water Chemistry (SSWC) model to estimate critical loads for acid deposition and investigate the current vulnerability of high elevation lakes to acid deposition. The majority of the lakes were dilute (...

  8. The Irminger Sea and the Iceland Sea time series measurements of sea water carbon and nutrient chemistry 1983–2008

    Directory of Open Access Journals (Sweden)

    J. Olafsson

    2010-03-01

    Full Text Available This paper describes the ways and means of assembling and quality controling the Irminger Sea and Iceland Sea time-series biogeochemical data which are included in the CARINA data set. The Irminger Sea and the Iceland Sea are hydrographically different regions where measurements of sea water carbon and nutrient chemistry were started in 1983. The sampling is seasonal, four times a year. The carbon chemistry is studied with measurements of the partial pressure of carbon dioxide in seawater, pCO2, and total dissolved inorganic carbon, TCO2. The carbon chemistry data are for surface waters only until 1991 when water column sampling was initiated. Other measured parameters are salinity, dissolved oxygen and the inorganic nutrients nitrate, phosphate and silicate. Because of the CARINA criteria for secondary quality control, depth >1500 m, the IRM-TS could not be included in the routine QC and the IS-TS only in a limited way. However, with the information provided here, the quality of the data can be assessed, e.g. on the basis of the results obtained with the use of reference materials.

  9. Understanding flood-induced water chemistry variability extracting temporal patterns with the LDA method

    Science.gov (United States)

    Aubert, A. H.; Tavenard, R.; Emonet, R.; De Lavenne, A.; Malinowski, S.; Guyet, T.; Quiniou, R.; Odobez, J.; Merot, P.; Gascuel-odoux, C.

    2013-12-01

    Studying floods has been a major issue in hydrological research for years, both in quantitative and qualitative hydrology. Stream chemistry is a mix of solutes, often used as tracers, as they originate from various sources in the catchment and reach the stream by various flow pathways. Previous studies (for instance (1)) hypothesized that stream chemistry reaction to a rainfall event is not unique but varies seasonally, and according to the yearly meteorological conditions. Identifying a typology of flood temporal chemical patterns is a way to better understand catchment processes at the flood and seasonal time scale. We applied a probabilistic model (Latent Dirichlet Allocation or LDA (2)) mining recurrent sequential patterns from a dataset of floods. A set of 472 floods was automatically extracted from a daily 12-year long record of nitrate, dissolved organic carbon, sulfate and chloride concentrations. Rainfall, discharge, water table depth and temperature are also considered. Data comes from a long-term hydrological observatory (AgrHys, western France) located at Kervidy-Naizin. From each flood, a document has been generated that is made of a set of "hydrological words". Each hydrological word corresponds to a measurement: it is a triplet made of the considered variable, the time at which the measurement is made (relative to the beginning of the flood), and its magnitude (that can be low, medium or high). The documents and the number of pattern to be mined are used as input data to the LDA algorithm. LDA relies on spotting co-occurrences (as an alternative to the more traditional study of correlation) between words that appear within the flood documents. It has two nice properties that are its ability to easily deal with missing data and its additive property that allows a document to be seen as a mixture of several flood patterns. The output of LDA is a set of patterns easily represented in graphics. These patterns correspond to typical reactions to rainfall

  10. Photocatalytic Oxidation and Reduction Chemistry and a New Process for Treatment of Pink Water and Related Contaminated Water

    National Research Council Canada - National Science Library

    Blake, D

    1996-01-01

    ...), and by a group at the University of Idaho (UI) working under subcontract to NREL. The initial focus was on photocatalytic oxidation and reduction chemistry that could use sunlight as the photon source...

  11. Modelling characteristics to predict Legionella contamination risk - Surveillance of drinking water plumbing systems and identification of risk areas.

    Science.gov (United States)

    Völker, Sebastian; Schreiber, Christiane; Kistemann, Thomas

    2016-01-01

    For the surveillance of drinking water plumbing systems (DWPS) and the identification of risk factors, there is a need for an early estimation of the risk of Legionella contamination within a building, using efficient and assessable parameters to estimate hazards and to prioritize risks. The precision, accuracy and effectiveness of ways of estimating the risk of higher Legionella numbers (temperature, stagnation, pipe materials, etc.) have only rarely been empirically assessed in practice, although there is a broad consensus about the impact of these risk factors. We collected n = 807 drinking water samples from 9 buildings which had had Legionella spp. occurrences of >100 CFU/100mL within the last 12 months, and tested for Legionella spp., L. pneumophila, HPC 20°C and 36°C (culture-based). Each building was sampled for 6 months under standard operating conditions in the DWPS. We discovered high variability (up to 4 log(10) steps) in the presence of Legionella spp. (CFU/100 mL) within all buildings over a half year period as well as over the course of a day. Occurrences were significantly correlated with temperature, pipe length measures, and stagnation. Logistic regression modelling revealed three parameters (temperature after flushing until no significant changes in temperatures can be obtained, stagnation (low withdrawal, qualitatively assessed), pipe length proportion) to be the best predictors of Legionella contamination (>100 CFU/100 mL) at single outlets (precision = 66.7%; accuracy = 72.1%; F(0.5) score = 0.59). Copyright © 2015 Elsevier GmbH. All rights reserved.

  12. Trait modality distribution of aquatic macrofauna communities as explained by pesticides and water chemistry.

    Science.gov (United States)

    Ieromina, O; Musters, C J M; Bodegom, P M; Peijnenburg, W J G M; Vijver, M G

    2016-08-01

    Analyzing functional species' characteristics (species traits) that represent physiological, life history and morphological characteristics of species help understanding the impacts of various stressors on aquatic communities at field conditions. This research aimed to study the combined effects of pesticides and other environmental factors (temperature, dissolved oxygen, dissolved organic carbon, floating macrophytes cover, phosphate, nitrite, and nitrate) on the trait modality distribution of aquatic macrofauna communities. To this purpose, a field inventory was performed in a flower bulb growing area of the Netherlands with significant variation in pesticides pressures. Macrofauna community composition, water chemistry parameters and pesticide concentrations in ditches next to flower bulb fields were determined. Trait modalities of nine traits (feeding mode, respiration mode, locomotion type, resistance form, reproduction mode, life stage, voltinism, saprobity, maximum body size) likely to indicate pesticides impacts were analyzed. According to a redundancy analysis, phosphate -and not pesticides- constituted the main factor structuring the trait modality distribution of aquatic macrofauna. The functional composition could be ascribed for 2-4 % to pesticides, and for 3-11 % to phosphate. The lack of trait responses to pesticides may indicate that species may have used alternative strategies to adapt to ambient pesticides stress. Biomass of animals exhibiting trait modalities related to feeding by predation and grazing, presence of diapause form or dormancy, reproduction by free clutches and ovoviviparity, life stage of larvae and pupa, was negatively correlated to the concentration of phosphate. Hence, despite the high pesticide pollution in the area, variation in nutrient-related stressors seems to be the dominant driver of the functional composition of aquatic macrofauna assembly in agricultural ditches.

  13. The Acute Toxicity of Major Ion Salts to Ceriodaphnia dubia: I. Influence of background water chemistry.

    Data.gov (United States)

    U.S. Environmental Protection Agency — This dataset provides concentration-response data and associated general chemistry conditions for 26 experiments consisting of 149 tests regarding the acute toxicity...

  14. NWFSC OA facility water chemistry - Ocean acidification species exposure experimental facility

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — We have developed a unique facility for conducting high-quality experiments on marine organisms in seawater with controlled carbon chemistry conditions. The...

  15. Sediment trap and water column chemistry, Baltimore Canyon, U.S. Mid-Atlantic Bight

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Time-series of sediment chemistry, including organic biomarker composition and bulk inorganic geochemical analytes, from samples collected over a one-year period in...

  16. Role of Water in Electron-Initiated Processes and Radical Chemistry: Issues and Scientific Advances

    Energy Technology Data Exchange (ETDEWEB)

    Garrett, Bruce C.; Dixon, David A.; Camaioni, Donald M.; Chipman, Daniel M.; Johnson, Mark A.; Jonah, Charles D.; Kimmel, Greg A.; Miller, John H.; Rescigno, Tom; Rossky, Peter J.; Xantheas, Sotiris S.; Colson, Steve D.; Laufer, Allan H.; Ray, Douglas; Barbara, Paul F.; Bartels, David M.; Bowen, Kit H.; Becker, Kurt H.; Bradforth, Stephen E.; Carmichael, Ian; Coe, James V.; Corrales, L. Rene; Cowin, James P.; Dupuis, Michel; Eisenthal, Kenneth B.; Franz, James A.; Gutowski, Maciej S.; Jordon, Kenneth D.; Kay, Bruce D.; La Verne, Jay A.; Lymar, Sergei V.; Madey, Theodore E.; Mccurdy, C. W.; Meisel, Dan; Mukamel, Shaul; Nilsson, Anders R.; Orlando, Thomas M.; Petrik, Nikolay G.; Pimblott, Simon M.; Rustad, James R.; Schenter, Gregory K.; Singer, Sherwin J.; Tokmakoff, Andrei; Wang, Lai-Sheng; Wittig, Curt; Zwier, Timothy S.

    2005-01-12

    An understanding of electron-initiated processes in aqueous systems and the subsequent radical chemistry these processes induce is significant in such diverse fields as waste remediation and environmental cleanup, radiation processing, nuclear reactors, and medical diagnosis and therapy. We review the state of the art in the physical chemistry and chemical physics of electron-initiated processes in aqueous systems and raise critical research issues and fundamental questions that remain unanswered.

  17. Standard Master Matrix for Light-Water Reactor Pressure Vessel Surveillance Standards, E706(0)

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2002-01-01

    1.1 This master matrix standard describes a series of standard practices, guides, and methods for the prediction of neutron-induced changes in light-water reactor (LWR) pressure vessel (PV) and support structure steels throughout a pressure vessel's service life (Fig. 1). Some of these are existing ASTM standards, some are ASTM standards that have been modified, and some are proposed ASTM standards. General requirements of content and consistency are discussed in Section 6 . More detailed writers' and users' information, justification, and specific requirements for the nine practices, ten guides, and three methods are provided in Sections 3-5. Referenced documents are discussed in Section 2. The summary-type information that is provided in Sections 3 and 4 is essential for establishing proper understanding and communications between the writers and users of this set of matrix standards. It was extracted from the referenced documents, Section 2 and references (1-106) for use by individual writers and users. 1...

  18. Differences in Temperature and Water Chemistry Shape Distinct Diversity Patterns in Thermophilic Microbial Communities.

    Science.gov (United States)

    Chiriac, Cecilia M; Szekeres, Edina; Rudi, Knut; Baricz, Andreea; Hegedus, Adriana; Dragoş, Nicolae; Coman, Cristian

    2017-11-01

    areas are isolated and have a limited exchange of organisms, nutrients, and energy with the surrounding environments, hot spring microbial communities can be used in model studies to elucidate the colonizing potential within extreme settings. Thus, they are of great importance in evolutionary biology, microbial ecology, and exobiology. In spite of all the efforts that have been made, the current understanding of the influence of temperature and water chemistry on the microbial community composition, diversity, and abundance in microbial mats is limited. In this study, the composition and diversity of microbial communities developed in thermal gradients in the vicinity of three hot springs from Romania were investigated, each having particular physicochemical characteristics. Our results expose new factors that could determine the formation of these ecosystems, expanding the current knowledge in this regard. Copyright © 2017 American Society for Microbiology.

  19. Water physics and chemistry data from bottle casts from the DELAWARE from 10 May 1967 to 01 June 1967 (NODC Accession 7000769)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Water physics and chemistry data were collected from bottle casts from the DELAWARE from 10 May 1967 to 01 June 1967. Data were submitted by the National Marine...

  20. Water physics and chemistry data from bottle casts from the CHESAPEAKE L/S and other platforms from 28 November 1955 to 31 December 1956 (NODC Accession 6800101)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Water physics and chemistry data were collected from bottle casts from the CHESAPEAKE L/S and other platforms from 28 November 1955 to 31 December 1956. Data were...

  1. Hydrology and water chemistry of the Benton Lake basin with emphasis on the fate of dissolved solids at Benton Lake National Wildlife Refuge, west-central Montana

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report is on a hydro geochemical study of the Benton Lake basin, in Benton Lake National Wildlife Refige. Toe hydrology and water chemistry of the Benton Lake...

  2. Water physics and chemistry data from bottle casts from the AQUALAB from 14 October 1968 to 11 December 1968 (NODC Accession 7100270)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Water physics and chemistry data were collected from bottle casts from the AQUALAB from 14 October 1968 to 11 December 1968. Data were submitted by the Southern...

  3. Water physics and chemistry data from STD casts from THELMA DALE II and other platforms from 09 August 1954 to 05 March 1959 (NODC Accession 7101380)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Water physics and chemistry data were collected from STD casts from THELMA DALE II and other platforms from 09 August 1954 to 05 March 1959. Data were submitted by...

  4. Water physics and chemistry data from bottle casts from the TAGE from 08 May 1969 to 30 December 1969 (NODC Accession 7100605)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Water physics and chemistry data were collected from bottle casts from the TAGE from 08 May 1969 to 30 December 1969. Data were submitted by the Stanford University;...

  5. Water physics and chemistry data from bottle casts from the AMIGO as part of the SEAGRANT project from 19 January 1972 to 20 April 1973 (NODC Accession 7400540)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Water physics and chemistry data were collected from bottle casts from the AMIGO from 19 January 1972 to 20 April 1973. Data were submitted by the Moss Landing...

  6. Ditch blocking, water chemistry and organic carbon flux: evidence that blanket bog restoration reduces erosion and fluvial carbon loss.

    Science.gov (United States)

    Wilson, Lorraine; Wilson, Jared; Holden, Joseph; Johnstone, Ian; Armstrong, Alona; Morris, Michael

    2011-05-01

    The potential for restoration of peatlands to deliver benefits beyond habitat restoration is poorly understood. There may be impacts on discharge water quality, peat erosion, flow rates and flood risk, and nutrient fluxes. This study aimed to assess the impact of drain blocking, as a form of peatland restoration, on an upland blanket bog, by measuring water chemistry and colour, and loss of both dissolved (DOC) and particulate organic carbon (POC). The restoration work was designed to permit the collection of a robust experimental dataset over a landscape scale, with data covering up to 3 years pre-restoration and up to 3 years post-restoration. An information theoretic approach to data analyses provided evidence of a recovery of water chemistry towards more 'natural' conditions, and showed strong declines in the production of water colour. Drain blocking led to increases in the E4:E6 ratio, and declines in specific absorbance, suggesting that DOC released from blocked drains consisted of lighter, less humic and less decomposed carbon. Whilst concentrations of DOC showed slight increases in drains and streams after blocking, instantaneous yields of both DOC and POC declined markedly in streams over the first year post-restoration. Attempts were made to estimate total annual fluvial organic carbon fluxes for the study site, and although errors around these estimates remain considerable, there is strong evidence of a large reduction in aquatic organic carbon flux from the peatland following drain-blocking. Potential mechanisms for the observed changes in water chemistry and organic carbon release are discussed, and we highlight the need for more detailed information, from more sites, to better understand the full impacts of peatland restoration on carbon storage and release. Copyright © 2011 Elsevier B.V. All rights reserved.

  7. Single-Step Synthesis of Small, Azide-Functionalized Gold Nanoparticles: Versatile, Water-Dispersible Reagents for Click Chemistry.

    Science.gov (United States)

    Elliott, Edward W; Ginzburg, Aurora L; Kennedy, Zachary C; Feng, Zhenshuo; Hutchison, James E

    2017-06-13

    Nanoparticles possessing functional groups that can be readily conjugated (e.g., through click chemistry) are important precursors for the preparation of customized nanohybrid products. Such nanoparticles, if they are stable against agglomeration, are easily dispersible and have well-defined surface chemistry and size. As click-ready reagents, they can be stored until their time of use and then simply dispersed and reacted with an appropriate substrate. Gold nanoparticles (AuNPs) are excellent candidates for this purpose, and some clickable gold nanoparticles have been developed; however, AuNPs for use in aqueous systems are often prepared through difficult multistep processes and/or can be poorly dispersible in water. Here we report a single-step synthesis of clickable, water-dispersible AuNPs. The synthesis yields uniform, 3.5 nm diameter cores coated with a well-defined molecular ligand shell that makes the AuNPs stable and dispersible in water. The AuNP mixed ligand shell consists of hydroxyl-terminated ethylene glycol-based ligands to promote dispersion in water and a small number of azide-terminated ligands that readily undergo click reactions with alkynes. The use of a mesofluidic reactor affords fine control over the core size and ligand shell composition and ensures reproducible results (e.g., less than 0.1 nm variation in core diameter between batches). The purified reagents were successfully coupled to a variety of alkyne-containing substrates using both Cu-catalyzed and strain-promoted click reactions. Particle size, morphology, stability, and surface composition were thoroughly characterized using small-angle X-ray scattering, transmission electron microscopy, X-ray photoelectron spectroscopy, UV-vis, and 1 H NMR before and after the click reactions. Both the parent nanoparticles and their click chemistry products are stable during storage and remained dispersible for over a year in water, suggesting their potential for environmental, biological, and

  8. Introduction to surveillance studies

    CERN Document Server

    Petersen, JK

    2012-01-01

    Introduction & OverviewIntroduction Brief History of Surveillance Technologies & TechniquesOptical SurveillanceAerial Surveillance Audio Surveillance Radio-Wave SurveillanceGlobal Positioning Systems Sensors Computers & the Internet Data Cards Biochemical Surveillance Animal Surveillance Biometrics Genetics Practical ConsiderationsPrevalence of Surveillance Effectiveness of Surveillance Freedom & Privacy IssuesConstitutional Freedoms Privacy Safeguards & Intrusions ResourcesReferences Glossary Index

  9. Hydrogeologic framework refinement, ground-water flow and storage, water-chemistry analyses, and water-budget components of the Yuma area, southwestern Arizona and southeastern California

    Science.gov (United States)

    Dickinson, Jesse E.; Land, Michael; Faunt, Claudia C.; Leake, S.A.; Reichard, Eric G.; Fleming, John B.; Pool, D.R.

    2006-01-01

    The ground-water and surface-water system in the Yuma area in southwestern Arizona and southeastern California is managed intensely to meet water-delivery requirements of customers in the United States, to manage high ground-water levels in the valleys, and to maintain treaty-mandated water-quality and quantity requirements of Mexico. The following components in this report, which were identified to be useful in the development of a ground-water management model, are: (1) refinement of the hydrogeologic framework; (2) updated water-level maps, general ground-water flow patterns, and an estimate of the amount of ground water stored in the mound under Yuma Mesa; (3) review and documentation of the ground-water budget calculated by the Bureau of Reclamation, U.S. Department of the Interior (Reclamation); and (4) water-chemistry characterization to identify the spatial distribution of water quality, information on sources and ages of ground water, and information about the productive-interval depths of the aquifer. A refined three-dimensional digital hydrogeologic framework model includes the following hydrogeologic units from bottom to top: (1) the effective hydrologic basement of the basin aquifer, which includes the Pliocene Bouse Formation, Tertiary volcanic and sedimentary rocks, and pre-Tertiary metamorphic and plutonic rocks; (2) undifferentiated lower units to represent the Pliocene transition zone and wedge zone; (3) coarse-gravel unit; (4) lower, middle, and upper basin fill to represent the upper, fine-grained zone between the top of the coarse-gravel unit and the land surface; and (5) clay A and clay B. Data for the refined model includes digital elevation models, borehole lithology data, geophysical data, and structural data to represent the geometry of the hydrogeologic units. The top surface of the coarse-gravel unit, defined by using borehole and geophysical data, varies similarly to terraces resulting from the down cutting of the Colorado River. Clay A

  10. Surveillance Pleasures

    DEFF Research Database (Denmark)

    Albrechtslund, Anders

    and leisure have not been studied with the same intensity as e.g. policing, civil liberties and social sorting. This paper offers a study of trends in surveillance pleasures, i.e. watching and eavesdropping in popular culture. My focus is the existential aspects and ethical dilemmas of surveillance...

  11. Effects of water chemistry on the dissolution of ZnO nanoparticles and their toxicity to Escherichia coli.

    Science.gov (United States)

    Li, Mei; Lin, Daohui; Zhu, Lizhong

    2013-02-01

    The dissolution of ZnO nanoparticles (nano-ZnO) plays an important role in the toxicity of nano-ZnO to the aquatic organisms. The effects of water chemistry such as pH, ionic components, and dissolved organic matter (DOM) on the dissolution of nano-ZnO and its toxicity to Escherichia coli (E. coli) were investigated in synthetic and natural water samples. The results showed that the toxicity of nano-ZnO to E. coli depended on not only free Zn(2+) but also the coexisting cations which could reduce the toxicity of Zn(2+). Increasing solution pH, HPO(4)(2), and DOM reduced the concentration of free Zn(2+) released from nano-ZnO, and thus lowered the toxicity of nano-ZnO. In addition, both Ca(2+) and Mg(2+) dramatically reduced the toxicity of Zn(2+) to E. coli. These results highlight the importance of water chemistry on the toxicity evaluation of nano-ZnO in natural waters. Copyright © 2012 Elsevier Ltd. All rights reserved.

  12. Aespoe Hard Rock Laboratory. Prototype Repository. Analyses of microorganisms, gases and water chemistry in buffer and backfill, 2009

    Energy Technology Data Exchange (ETDEWEB)

    Lydmark, Sara (Microbial Analytics Sweden AB (Sweden))

    2010-09-15

    The Prototype repository is an international project to build and study a full-scale model of the planned Swedish final repository for spent nuclear fuel. The Prototype repository differs from a real storage in that it is drained. For example, this makes the swelling pressure lower in the Prototype repository compared with a real storage. The project is being conducted at the Aespoe Hard Rock Laboratory (HRL) in crystalline rock at a depth of approximately 450 m. A monitoring programme is investigating the evolution of the water chemistry, gas, and microbial activity at the site, and one of the specific aims is to monitor the microbial consumption of oxygen in situ in the Prototype repository. This document describes the results of the analyses of microbes, gases, and chemistry inside and outside the Prototype in 2009. Hydrogen, helium, nitrogen, oxygen, carbon monoxide, carbon dioxide, methane, ethane, and ethene were analysed in the following sampling points in the Prototype repository: KBU10001, KBU10002, KBU10004, KBU10006, KBU10008, KFA01 and KFA04. Where the sampling points in the Prototype delivered pore water, the water was analysed for amount of ATP (i.e., the biovolume), cultivable heterotrophic aerobic bacteria (CHAB), sulphate-reducing bacteria (SRB), methane-oxidizing bacteria (MOB), autotrophic acetogens (AA) and in some cases iron-reducing bacteria (IRB). Cultivation methods were also compared with qPCR molecular techniques to evaluate these before next year's decommission of the Prototype repository. The collected pore water from the Prototype repository was subject to chemistry analysis (as many analyses were conducted as the amount of water allowed). In addition, groundwater from two borehole sections in the rock surrounding the Prototype was analysed regarding its gas composition, microbiology and redox. Chemistry data from a previous investigation of the groundwater outside the Prototype repository were compared with the pore water

  13. Vertical gradients in water chemistry in the central High Plains aquifer, southwestern Kansas and Oklahoma panhandle, 1999

    Science.gov (United States)

    McMahon, Peter B.

    2001-01-01

    The central High Plains aquifer is the primary source of water for domestic, industrial, and irrigation uses in parts of Colorado, Kansas, New Mexico, Oklahoma, and Texas. Water-level declines of more than 100 feet in some areas of the aquifer have increased the demand for water deeper in the aquifer. The maximum saturated thickness of the aquifer ranged from 500 to 600 feet in 1999. As the demand for deeper water increases, it becomes increasingly important for resource managers to understand how the quality of water in the aquifer changes with depth. In 1998?99, 18 monitoring wells at nine sites in southwestern Kansas and the Oklahoma Panhandle were completed at various depths in the central High Plains aquifer, and one monitoring well was completed in sediments of Permian age underlying the aquifer. Water samples were collected once from each well in 1999 to measure vertical gradients in water chemistry in the aquifer. Tritium concentrations measured in ground water indicate that water samples collected in the upper 30 feet of the aquifer were generally recharged within the last 50 years, whereas all of the water samples collected at depths more than 30 feet below the water table were recharged more than 50 years ago. Dissolved oxygen was present throughout the aquifer, with concentrations ranging from 1.7 to 8.4 mg/L. Water in the central High Plains aquifer was predominantly a calcium-bicarbonate type that exhibited little variability in concentrations of dissolved solids with depth (290 to 642 mg/L). Exceptions occurred in some areas where there had been upward movement of mineralized water from underlying sediments of Permian age and areas where there had been downward movement of mineralized Arkansas River water to the aquifer. Calcium-sulfate and sodium-chloride waters dominated and concentrations of dissolved solids were elevated (862 to 4,030 mg/L) near the base of the aquifer in the areas of upward leakage. Dissolution of gypsum or anhydrite and halite

  14. Surface Environmental Surveillance Project: Locations Manual Volume 1 – Air and Water Volume 2 – Farm Products, Soil & Vegetation, and Wildlife

    Energy Technology Data Exchange (ETDEWEB)

    Fritz, Brad G.; Patton, Gregory W.; Stegen, Amanda; Poston, Ted M.

    2009-01-01

    This report describes all environmental monitoring locations associated with the Surface Environmental Surveillance Project. Environmental surveillance of the Hanford site and surrounding areas is conducted by the Pacific Northwest National Laboratory (PNNL) for the U.S. Department of Energy (DOE). Sampling is conducted to evaluate levels of radioactive and nonradioactive pollutants in the Hanford environs, as required in DOE Order 450.1, Environmental Protection Program, and DOE Order 5400.5, Radiation Protection of the Public and the Environment. The environmental surveillance sampling design is described in the Hanford Site Environmental Monitoring Plan, United States Department of Energy, Richland Operation Office (DOE/RL-91-50). This document contains the locations of sites used to collect samples for the Surface Environmental Surveillance Project (SESP). Each section includes directions, maps, and pictures of the locations. A general knowledge of roads and highways on and around the Hanford Site is necessary to successfully use this manual. Supplemental information (Maps, Gazetteer, etc.) may be necessary if user is unfamiliar with local routes. The SESP is a multimedia environmental surveillance effort to measure the concentrations of radionuclides and chemicals in environmental media to demonstrate compliance with applicable environmental quality standards and public exposure limits, and assessing environmental impacts. Project personnel annually collect selected samples of ambient air, surface water, agricultural products, fish, wildlife, and sediments. Soil and vegetation samples are collected approximately every 5 years. Analytical capabilities include the measurement of radionuclides at very low environmental concentrations and, in selected media, nonradiological chemicals including metals, anions, volatile organic compounds, and total organic carbon.

  15. The role of water chemistry for environmentally assisted cracking in low-alloy reactor pressure vessel and piping steels under boiling reactor conditions

    Energy Technology Data Exchange (ETDEWEB)

    Seifert, H.-P.; Ritter, S

    2005-07-01

    The environmentally assisted initiation and propagation of cracks in structural materials is one of the most important degradation and ageing mechanisms in light water reactors (LWR) and may seriously affect plant availability and economics. In the first part of this paper a short general introduction on environmentally assisted cracking (EAC) and its significance for LWR is given. Then the important role of water chemistry control in reducing the EAC risk in LWR is illustrated by current research results about the effect of chloride transients and hydrogen water chemistry on the EAC crack growth behaviour of low-alloy reactor pressure vessel and piping steels under boiling water reactor conditions. (author)

  16. Water-Chemistry Evolution and Modeling of Radionuclide Sorption and Cation Exchange during Inundation of Frenchman Flat Playa

    Energy Technology Data Exchange (ETDEWEB)

    Hershey, Ronald; Cablk, Mary; LeFebre, Karen; Fenstermaker, Lynn; Decker, David

    2013-08-01

    valuable information about chemical processes occurring during inundation as the water disappeared. Important observations from water-chemistry analyses included: 1) total dissolved solids (TDS) and chloride ion (Cl-) concentrations were very low (TDS: < 200 mg/L and Cl-: < 3.0 mg/L, respectively) for all water samples regardless of time or areal extent; 2) all dissolved constituents were at concentrations well below what might be expected for evaporating shallow surface waters on a playa, even when 98 to 99 percent of the water had disappeared; 3) the amount of evaporation for the last water samples collected at the end of inundation, estimated with the stable isotopic ratios δ2H or δ18O, was approximately 60 percent; and 4) water samples analyzed by gamma spectroscopy did not show any man-made radioactivity; however, the short scanning time (24 hours) and relative chemical diluteness of the water samples (TDS ranged between 39 and 190 mg/L) may have contributed to none being detected. Additionally, any low-energy beta emitting radionuclides would not have been detected by gamma spectroscopy. From these observations, it was apparent that a significant portion of water on the playa did not evaporate, but rather infiltrated into the subsurface (approximately 40 percent). Consistent with this water chemistry-based conclusion is particle-size analysis of two archived Frenchman Flat playa soils samples, which showed low clay content in the near surface soil that also suggested infiltration. Infiltration of water from the playa during inundation into the subsurface does not necessarily imply that groundwater recharge is occurring, but it does provide a mechanism for moving residual radionuclides downward into the subsurface of Frenchman Flat playa. Water-mineral geochemical reactions were modeled so that changes in the water chemistry could be identified and the extent of reactions quantified. Geochemical modeling showed that evaporation; equilibrium with atmospheric carbon

  17. Radiation Chemistry

    Science.gov (United States)

    Wojnárovits, L.

    Ionizing radiation causes chemical changes in the molecules of the interacting medium. The initial molecules change to new molecules, resulting in changes of the physical, chemical, and eventually biological properties of the material. For instance, water decomposes to its elements H2 and O2. In polymers, degradation and crosslinking take place. In biopolymers, e.g., DNS strand breaks and other alterations occur. Such changes are to be avoided in some cases (radiation protection), however, in other cases they are used for technological purposes (radiation processing). This chapter introduces radiation chemistry by discussing the sources of ionizing radiation (radionuclide sources, machine sources), absorption of radiation energy, techniques used in radiation chemistry research, and methods of absorbed energy (absorbed dose) measurements. Radiation chemistry of different classes of inorganic (water and aqueous solutions, inorganic solids, ionic liquids (ILs)) and organic substances (hydrocarbons, halogenated compounds, polymers, and biomolecules) is discussed in concise form together with theoretical and experimental backgrounds. An essential part of the chapter is the introduction of radiation processing technologies in the fields of polymer chemistry, food processing, and sterilization. The application of radiation chemistry to nuclear technology and to protection of environment (flue gas treatment, wastewater treatment) is also discussed.

  18. Water chemistry, seepage investigation, streamflow, reservoir storage, and annual availability of water for the San Juan-Chama Project, northern New Mexico, 1942-2010

    Science.gov (United States)

    McKean, Sarah E.; Anderholm, Scott K.

    2014-01-01

    The Albuquerque Bernalillo County Water Utility Authority supplements the municipal water supply for the Albuquerque metropolitan area, in central New Mexico, with surface water diverted from the Rio Grande. The U.S. Geological Survey, in cooperation with the Albuquerque Bernalillo County Water Utility Authority, undertook this study in which water-chemistry data and historical streamflow were compiled and new water-chemistry data were collected to characterize the water chemistry and streamflow of the San Juan-Chama Project (SJCP). Characterization of streamflow included analysis of the variability of annual streamflow and comparison of the theoretical amount of water that could have been diverted into the SJCP to the actual amount of water that was diverted for the SJCP. Additionally, a seepage investigation was conducted along the channel between Azotea Tunnel Outlet and the streamflow-gaging station at Willow Creek above Heron Reservoir to estimate the magnitude of the gain or loss in streamflow resulting from groundwater interaction over the approximately 10-mile reach. Generally, surface-water chemistry varied with streamflow throughout the year. Streamflow ranged from high flow to low flow on the basis of the quantity of water diverted from the Rio Blanco, Little Navajo River, and Navajo River for the SJCP. Vertical profiles of the water temperature over the depth of the water column at Heron Reservoir indicated that the reservoir is seasonally stratified. The results from the seepage investigations indicated a small amount of loss of streamflow along the channel. Annual variability in streamflow for the SJCP was an indication of the variation in the climate parameters that interact to contribute to streamflow in the Rio Blanco, Little Navajo River, Navajo River, and Willow Creek watersheds. For most years, streamflow at Azotea Tunnel Outlet started in March and continued for approximately 3 months until the middle of July. The majority of annual streamflow

  19. The major and trace element chemistry of fish and lake water within ...

    African Journals Online (AJOL)

    2016-01-01

    Jan 1, 2016 ... Co and Ni are thus incorporated into otoliths in a fashion indicat- ing environmental chemistry rather than differences between species. The bass populations from Lake Middelburg and Lake. Witbank contain one individual each that has extremely elevated Ni/Fe otolith ratios (Fig. 4). These lakes are directly.

  20. Effects of management on aquatic tree-hole communities in temperate forests are mediated by detritus amount and water chemistry.

    Science.gov (United States)

    Gossner, Martin M; Lade, Peggy; Rohland, Anja; Sichardt, Nora; Kahl, Tiemo; Bauhus, Jürgen; Weisser, Wolfgang W; Petermann, Jana S

    2016-01-01

    Arthropod communities in water-filled tree holes may be sensitive to impacts of forest management, for example via changes in environmental conditions such as resource input. We hypothesized that increasing forest management intensity (ForMI) negatively affects arthropod abundance and richness and shifts community composition and trophic structure of tree hole communities. We predicted that this shift is caused by reduced habitat and resource availability at the forest stand scale as well as reduced tree hole size, detritus amount and changed water chemistry at the tree holes scale. We mapped 910 water-filled tree holes in two regions in Germany and studied 199 tree hole inhabiting arthropod communities. We found that increasing ForMI indeed significantly reduced arthropod abundance and richness in water-filled tree holes. The most important indirect effects of management intensity on tree hole community structure were the reduced amounts of detritus for the tree hole inhabiting organisms and changed water chemistry at the tree hole scale, both of which seem to act as a habitat filter. Although habitat availability at the forest stand scale decreased with increasing management intensity, this unexpectedly increased local arthropod abundance in individual tree holes. However, regional species richness in tree holes significantly decreased with increasing management intensity, most likely due to decreased habitat diversity. We did not find that the management-driven increase in plant diversity at the forest stand scale affected communities of individual tree holes, for example via resource availability for adults. Our results suggest that management of temperate forests has to target a number of factors at different scales to conserve diverse arthropod communities in water-filled tree holes. © 2015 The Authors. Journal of Animal Ecology © 2015 British Ecological Society.

  1. Modifying Surface Chemistry of Metal Oxides for Boosting Dissolution Kinetics in Water by Liquid Cell Electron Microscopy.

    Science.gov (United States)

    Lu, Yue; Geng, Jiguo; Wang, Kuan; Zhang, Wei; Ding, Wenqiang; Zhang, Zhenhua; Xie, Shaohua; Dai, Hongxing; Chen, Fu-Rong; Sui, Manling

    2017-08-22

    Dissolution of metal oxides is fundamentally important for understanding mineral evolution and micromachining oxide functional materials. In general, dissolution of metal oxides is a slow and inefficient chemical reaction. Here, by introducing oxygen deficiencies to modify the surface chemistry of oxides, we can boost the dissolution kinetics of metal oxides in water, as in situ demonstrated in a liquid environmental transmission electron microscope (LETEM). The dissolution rate constant significantly increases by 16-19 orders of magnitude, equivalent to a reduction of 0.97-1.11 eV in activation energy, as compared with the normal dissolution in acid. It is evidenced from the high-resolution TEM imaging, electron energy loss spectra, and first-principle calculations where the dissolution route of metal oxides is dynamically changed by local interoperability between altered water chemistry and surface oxygen deficiencies via electron radiolysis. This discovery inspires the development of a highly efficient electron lithography method for metal oxide films in ecofriendly water, which offers an advanced technique for nanodevice fabrication.

  2. Effect of Water Chemistry and Hydrodynamics on Nitrogen Transformation Activity and Microbial Community Functional Potential in Hyporheic Zone Sediment Columns

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Yuanyuan [Pacific Northwest National Laboratory, Richland, Washington 99354, United States; School; Liu, Chongxuan [Pacific Northwest National Laboratory, Richland, Washington 99354, United States; School; Nelson, William C. [Pacific Northwest National Laboratory, Richland, Washington 99354, United States; Shi, Liang [Pacific Northwest National Laboratory, Richland, Washington 99354, United States; School of Environmental; Xu, Fen [Pacific Northwest National Laboratory, Richland, Washington 99354, United States; School of Environmental; Liu, Yunde [Pacific Northwest National Laboratory, Richland, Washington 99354, United States; School of Environmental; Yan, Ailan [Pacific Northwest National Laboratory, Richland, Washington 99354, United States; Institute; Zhong, Lirong [Pacific Northwest National Laboratory, Richland, Washington 99354, United States; Thompson, Christopher [Pacific Northwest National Laboratory, Richland, Washington 99354, United States; Fredrickson, James K. [Pacific Northwest National Laboratory, Richland, Washington 99354, United States; Zachara, John M. [Pacific Northwest National Laboratory, Richland, Washington 99354, United States

    2017-04-11

    Nitrogen (N) transformation in hyporheic zone (HZ) is an important component in N-cycling in ecosystems. A column study was conducted to investigate N transformation in a HZ sediment with a focus on how characteristic HZ properties including water chemistry, fluid residence time, and dynamic groundwater and surface water exchange affect on N transformation. Metagenomic and quantitative polymerase chain reaction (qPCR) analyses were performed to evaluate the dynamic changes in microbial community structure and its function in response to N transformation. The results indicated that N transformation in the HZ sediment was collectively controlled by microbial community functions including: denitrification, dissimilatory nitrate reduction to ammonium (DNRA), nitrification, and anaerobic ammonium oxidation (anammox). However, the spatial distribution of the microbial community functions and associated biogeochemical reaction rates and products changed quickly in response to experimental perturbation, and was influenced by various factors including water chemistry (dissolved O2 and N species), desorption of sediment associated organic carbon, ion exchange reactions of NH4+, and fluid residence time. The results of this study implied that the microbial community in the HZ would exhibit strong function zonation along N and O gradients, which in turn would control the rates and products of N transformation.

  3. The impact of river infiltration on the chemistry of shallow groundwater in a reclaimed water irrigation area

    Science.gov (United States)

    Yin, Shiyang; Wu, Wenyong; Liu, Honglu; Bao, Zhe

    2016-10-01

    Reclaimed water reuse is an effective method of alleviating agricultural water shortages, which entails some potential risks for groundwater. In this study, the impacts of wastewater reuse on groundwater were evaluated by combination of groundwater chemistry and isotopes. In reclaimed water infiltration, salt composition was affected not only by ion exchange and dissolution equilibrium but also by carbonic acid equilibrium. The dissolution and precipitation of calcites and dolomites as well as exchange and adsorption between Na and Ca/Mg were simultaneous, leading to significant changes in Na/Cl, (Ca + Mg)/Cl, electrical conductivity (EC) and sodium adsorption ratio (SAR). The reclaimed water was of the Na-Mg-Ca-HCO3-Cl type, and groundwater recharged by reclaimed water was of the Na-Mg-HCO3 and Mg-Na-HCO3 types. The hydrogeological conditions characterized by sand-clay alternation led to both total nitrogen (TN) and total phosphorus (TP) removal efficiencies > 95%, and there was no significant difference in those contents between aquifers recharged by precipitation and reclamation water. > 40 years of long-term infiltration and recharge from sewage and reclaimed water did not cause groundwater contamination by nitrogen, phosphorus and heavy metals. These results indicate that characteristics of the study area, such as the lithologic structure with sand-clay alternation, relatively thick clay layer, and relatively large groundwater depth have a significant role in the high vulnerability.

  4. Effect of contact-type feedwater heaters on the water-chemistry of power-generating units

    Energy Technology Data Exchange (ETDEWEB)

    Permyakov, V.A.; Kuskov, I.A.; Efimochkin, G.I.; Ermolov, V.F.; Trifonov, N.N.; Taran, E.E.; Sokolov, B.M.; Gerasimov, V.V.

    1986-09-01

    Discusses the advantages of contact-type feedwater heaters, which include elimination of subcooling, improved reliability, and better feedwater quality. Details a number of designs of these heaters. Concludes that the use of these heaters is advisable with any water-chemistry conditions; stability of the required oxygen concentration in the feedheater is assured with venting of the steam volume of the deaerator and automatic dosing of oxygen at the inlet to the booster pumps; and that technical measures have been developed and applied which enable condensate to be thoroughly deaerated in contact-type low pressure heaters. 7 refs.

  5. Conducting water chemistry of the secondary coolant circuit of VVER-based nuclear power plant units constructed without using copper containing alloys

    Science.gov (United States)

    Tyapkov, V. F.

    2014-07-01

    The secondary coolant circuit water chemistry with metering amines began to be put in use in Russia in 2005, and all nuclear power plant units equipped with VVER-1000 reactors have been shifted to operate with this water chemistry for the past seven years. Owing to the use of water chemistry with metering amines, the amount of products from corrosion of structural materials entering into the volume of steam generators has been reduced, and the flow-accelerated corrosion rate of pipelines and equipment has been slowed down. The article presents data on conducting water chemistry in nuclear power plant units with VVER-1000 reactors for the secondary coolant system equipment made without using copper-containing alloys. Statistical data are presented on conducting ammonia-morpholine and ammonia-ethanolamine water chemistries in new-generation operating power units with VVER-1000 reactors with an increased level of pH. The values of cooling water leaks in turbine condensers the tube system of which is made of stainless steel or titanium alloy are given.

  6. Relationship between structural features and water chemistry in boreal headwater streams--evaluation based on results from two water management survey tools suggested for Swedish forestry.

    Science.gov (United States)

    Lestander, Ragna; Löfgren, Stefan; Henrikson, Lennart; Ågren, Anneli M

    2015-04-01

    Forestry may cause adverse impacts on water quality, and the forestry planning process is a key factor for the outcome of forest operation effects on stream water. To optimise environmental considerations and to identify actions needed to improve or maintain the stream biodiversity, two silvicultural water management tools, BIS+ (biodiversity, impact, sensitivity and added values) and Blue targeting, have been developed. In this study, we evaluate the links between survey variables, based on BIS+ and Blue targeting data, and water chemistry in 173 randomly selected headwater streams in the hemiboreal zone. While BIS+ and Blue targeting cannot replace more sophisticated monitoring methods necessary for classifying water quality in streams according to the EU Water Framework Directive (WFD, 2000/60/EC), our results lend support to the idea that the BIS+ protocol can be used to prioritise the protection of riparian forests. The relationship between BIS+ and water quality indicators (concentrations of nutrients and organic matter) together with data from fish studies suggests that this field protocol can be used to give reaches with higher biodiversity and conservation values a better protection. The tools indicate an ability to mitigate forestry impacts on water quality if the operations are adjusted to this knowledge in located areas.

  7. Characterizing interactions between surface water and groundwater in the Jialu River basin using major ion chemistry and stable isotopes

    Directory of Open Access Journals (Sweden)

    L. Yang

    2012-11-01

    Full Text Available The Jialu River, a secondary tributary of the Huaihe River, has been severely contaminated from major contaminant sources, such as a number of untreated or lightly treated sewage waste in some cities. Groundwater along the river is not an isolated component of the hydrologic system, but is instead connected with the surface water. This study aims to investigate temporal and spatial variations in water chemistry affected by humans and to characterize the relationships between surface water (e.g. reservoirs, lakes and rivers and groundwater near the river in the shallow Quaternary aquifer. Concentration of Cl in north Zhengzhou City increased prominently due to the discharge of a large amount of domestic water. Nitrate and potassium show maximum concentrations in groundwater in Fugou County. These high levels can be attributed to the use of a large quantity of fertilizer over this region. Most surface water appeared to be continuously recharged from the surrounding groundwater (regional wells based on comparison surface water with groundwater levels, stable-isotopes and major ion signatures. However, the groundwater of a transitional well (location SY3 seemed to be recharged by river water via bank infiltration in September 2010. Fractional contributions of river water to the groundwater were calculated based on isotopic and chemical data using a mass-balance approach. Results show that the groundwater was approximately composed of 60–70% river water. These findings should be useful for a better understanding of hydrogeological processes at the river-aquifer interface and ultimately benefit water management in the future.

  8. Characterization of the hydrology, water chemistry, and aquatic communities of selected springs in the St. Johns River Water Management District, Florida, 2004

    Science.gov (United States)

    Phelps, G.G.; Walsh, Stephen J.; Gerwig, Robert M.; Tate, William B.

    2006-01-01

    The hydrology, water chemistry, and aquatic communities of Silver Springs, De Leon Spring, Gemini Springs, and Green Spring in the St. Johns River Water Management District, Florida, were studied in 2004 to provide a better understanding of each spring and to compile data of potential use in future water-management decisions. Ground water that discharges from these and other north-central Florida springs originates from the Upper Floridan aquifer of the Floridan aquifer system, a karstic limestone aquifer that extends throughout most of the State's peninsula. This report summarizes data about flow, water chemistry, and aquatic communities, including benthic invertebrates, fishes, algae, and aquatic macrophytes collected by the U.S. Geological Survey, the St. Johns River Water Management District, and the Florida Department of Environmental Protection during 2004, as well as some previously collected data. Differences in water chemistry among these springs reflect local differences in water chemistry in the Upper Floridan aquifer. The three major springs sampled at the Silver Springs group (the Main Spring, Blue Grotto, and the Abyss) have similar proportions of cations and anions but vary in nitrate and dissolved oxygen concentrations. Water from Gemini Springs and Green Spring has higher proportions of sodium and chloride than the Silver Springs group. Water from De Leon Spring also has higher proportions of sodium and chloride than the Silver Springs group but lower proportions of calcium and bicarbonate. Nitrate concentrations have increased over the period of record at all of the springs except Green Spring. Compounds commonly found in wastewater were found in all the springs sampled. The most commonly detected compound was the insect repellant N,N'-diethyl-methyl-toluamide (DEET), which was found in all the springs sampled except De Leon Spring. The pesticide atrazine and its degradate 2-chloro-4-isopropylamino-6-amino-s-triazine (CIAT) were detected in water

  9. Does water chemistry affect the dietary uptake and toxicity of silver nanoparticles by the freshwater snail Lymnaea stagnalis?

    Science.gov (United States)

    López-Serrano Oliver, Ana; Croteau, Marie-Noële; Stoiber, Tasha L.; Tejamaya, Mila; Römer, Isabella; Lead, Jamie R.; Luoma, Samuel N.

    2014-01-01

    Silver nanoparticles (AgNPs) are widely used in many applications and likely released into the aquatic environment. There is increasing evidence that Ag is efficiently delivered to aquatic organisms from AgNPs after aqueous and dietary exposures. Accumulation of AgNPs through the diet can damage digestion and adversely affect growth. It is well recognized that aspects of water quality, such as hardness, affect the bioavailability and toxicity of waterborne Ag. However, the influence of water chemistry on the bioavailability and toxicity of dietborne AgNPs to aquatic invertebrates is largely unknown. Here we characterize for the first time the effects of water hardness and humic acids on the bioaccumulation and toxicity of AgNPs coated with polyvinyl pyrrolidone (PVP) to the freshwater snail Lymnaea stagnalis after dietary exposures. Our results indicate that bioaccumulation and toxicity of Ag from PVP-AgNPs ingested with food are not affected by water hardness and by humic acids, although both could affect interactions with the biological membrane and trigger nanoparticle transformations. Snails efficiently assimilated Ag from the PVP-AgNPs mixed with diatoms (Ag assimilation efficiencies ranged from 82 to 93%). Rate constants of Ag uptake from food were similar across the entire range of water hardness and humic acid concentrations. These results suggest that correcting regulations for water quality could be irrelevant and ineffective where dietary exposure is important.

  10. Multivariate statistical analysis of water chemistry conditions in three wastewater stabilization ponds with algae blooms and pH fluctuations.

    Science.gov (United States)

    Wallace, Jack; Champagne, Pascale; Hall, Geof

    2016-06-01

    The wastewater stabilization ponds (WSPs) at a wastewater treatment facility in eastern Ontario, Canada, have experienced excessive algae growth and high pH levels in the summer months. A full range of parameters were sampled from the system and the chemical dynamics in the three WSPs were assessed through multivariate statistical analysis. The study presents a novel approach for exploratory analysis of a comprehensive water chemistry dataset, incorporating principal components analysis (PCA) and principal components (PC) and partial least squares (PLS) regressions. The analyses showed strong correlations between chl-a and sunlight, temperature, organic matter, and nutrients, and weak and negative correlations between chl-a and pH and chl-a and DO. PCA reduced the data from 19 to 8 variables, with a good fit to the original data matrix (similarity measure of 0.73). Multivariate regressions to model system pH in terms of these key parameters were performed on the reduced variable set and the PCs generated, for which strong fits (R(2) > 0.79 with all data) were observed. The methodologies presented in this study are applicable to a wide range of natural and engineered systems where a large number of water chemistry parameters are monitored resulting in the generation of large data sets. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. The effects of human land use on flow regime and water chemistry of headwater streams in the highlands of Chiapas

    Directory of Open Access Journals (Sweden)

    Castillo M.M.

    2013-03-01

    Full Text Available We studied the effects of land use changes on flow regime and water chemistry of headwater streams in the highlands of Chiapas, a region in southern Mexico that has experienced high rates of deforestation in the last decades. Samples for water chemistry were collected and discharge was measured between September 2007 and August 2008 at eight streams that differed in the land uses of their riparian and catchment areas, including streams draining protected forested areas. Streams with high forest cover (>70% in their catchments maintained flow through the year. Streams draining more disturbed catchments exhibited reduced or no flow for 4 − 6 months during the dry season. Nitrate concentrations were lower at streams draining forested catchments while highest concentrations were measured where conventional agriculture covered a high proportion of the catchment and riparian zone. Highest phosphorus concentrations occurred at the catchment where poultry manure was applied as fertilizer. Differences between forest streams and those draining disturbed areas were correlated with the proportion of forest and agriculture in the riparian zone. Variation in stream variables among sampling dates was lower at the forest sites than at the more disturbed study streams. Conversion of forest into agriculture and urban areas is affecting flow regime and increasing nutrient concentrations, although the magnitude of the impacts are influenced by the type of agricultural practices and the alteration of the riparian zone.

  12. Stream water chemistry and quality along an upland lowland rural land-use continuum, south west England

    Science.gov (United States)

    Jarvie, H. P.; Haygarth, P. M.; Neal, C.; Butler, P.; Smith, B.; Naden, P. S.; Joynes, A.; Neal, M.; Wickham, H.; Armstrong, L.; Harman, S.; Palmer-Felgate, E. J.

    2008-02-01

    SummaryThis study examined stream water quality across a range of catchments which are representative of the key environments and land uses of rural south-west England. These catchments included: (a) an acidic upland headwater catchment, rising on the moorlands of Dartmoor, with low-intensity sheep rearing; (b) a headwater catchment rising on the weathered granite lower slopes of Dartmoor, with cattle farming; (c) a lowland headwater clay catchment with sub-surface drainage and high intensity livestock farming, fodder crop cultivation, and hard-standing/slurry storage; and (d) the main River Taw, a lowland river system receiving drainage from a range of tributaries, exemplified by the above catchment types. Variations in water chemistry and quality were observed along an upland-lowland transition, from headwater streams to the main river channel. Within the livestock-dominated headwater streams, total phosphorus (TP) was dominated by particulate phosphorus (PP). These PP concentrations appeared to be mainly linked to two sets of processes: (1) in-stream sediment precipitation with sorption/co-precipitation of phosphate and/or localised in-channel mobilisation of sediment (by cattle or channel-clearing operations) under low flow conditions, and (2) sediment erosion and transportation associated with near-surface runoff during storm events. Under baseflow conditions, in-stream and/or riparian processes played a significant role in controlling general nutrient chemistry, particularly in the headwater streams which were heavily impacted by livestock.

  13. Contribution of different processes to changes in tropical lower-stratospheric water vapor in chemistry-climate models

    Science.gov (United States)

    Smalley, Kevin M.; Dessler, Andrew E.; Bekki, Slimane; Deushi, Makoto; Marchand, Marion; Morgenstern, Olaf; Plummer, David A.; Shibata, Kiyotaka; Yamashita, Yousuke; Zeng, Guang

    2017-07-01

    Variations in tropical lower-stratospheric humidity influence both the chemistry and climate of the atmosphere. We analyze tropical lower-stratospheric water vapor in 21st century simulations from 12 state-of-the-art chemistry-climate models (CCMs), using a linear regression model to determine the factors driving the trends and variability. Within CCMs, warming of the troposphere primarily drives the long-term trend in stratospheric humidity. This is partially offset in most CCMs by an increase in the strength of the Brewer-Dobson circulation, which tends to cool the tropical tropopause layer (TTL). We also apply the regression model to individual decades from the 21st century CCM runs and compare them to a regression of a decade of observations. Many of the CCMs, but not all, compare well with these observations, lending credibility to their predictions. One notable deficiency is that most CCMs underestimate the impact of the quasi-biennial oscillation on lower-stratospheric water vapor. Our analysis provides a new and potentially superior way to evaluate model trends in lower-stratospheric humidity.

  14. Analysis of Pipe Wall-thinning Caused by Water Chemistry Change in Secondary System of Nuclear Power Plant

    Energy Technology Data Exchange (ETDEWEB)

    Yun, Hun; Hwang, Kyeongmo [KEPCO E and C, Gimcheon (Korea, Republic of); Moon, Seung-Jae [Hanyang University, Seoul (Korea, Republic of)

    2015-12-15

    Pipe wall-thinning by flow-accelerated corrosion (FAC) is a significant and costly damage of secondary system piping in nuclear power plants (NPPs). All NPPs have their management programs to ensure pipe integrity from wall-thinning. This study analyzed the pipe wall-thinning caused by changing the amine, which is used for adjusting the water chemistry in the secondary system of NPPs. The pH change was analyzed according to the addition of amine. Then, the wear rate calculated in two different amines was compared at the steam cycle in NPPs. As a result, increasing the pH at operating temperature (Hot pH) can reduce the rate of FAC damage significantly. Wall-thinning is affected by amine characteristics depending on temperature and quality of water.

  15. Impact of volcanic plume emissions on rain water chemistry during the January 2010 Nyamuragira eruptive event: implications for essential potable water resources.

    Science.gov (United States)

    Cuoco, Emilio; Tedesco, Dario; Poreda, Robert J; Williams, Jeremy C; De Francesco, Stefano; Balagizi, Charles; Darrah, Thomas H

    2013-01-15

    On January 2, 2010 the Nyamuragira volcano erupted lava fountains extending up to 300 m vertically along an ~1.5 km segment of its southern flank cascading ash and gas on nearby villages and cities along the western side of the rift valley. Because rain water is the only available potable water resource within this region, volcanic impacts on drinking water constitutes a major potential hazard to public health within the region. During the 2010 eruption, concerns were expressed by local inhabitants about water quality and feelings of physical discomfort (e.g. nausea, bloating, indigestion, etc.) after consuming rain water collected after the eruption began. We present the elemental and ionic chemistry of drinking water samples collected within the region on the third day of the eruption (January 5, 2010). We identify a significant impact on water quality associated with the eruption including lower pH (i.e. acidification) and increases in acidic halogens (e.g. F(-) and Cl(-)), major ions (e.g. SO(4)(2-), NH(4)(+), Na(+), Ca(2+)), potentially toxic metals (e.g. Al(3+), Mn(2+), Cd(2+), Pb(2+), Hf(4+)), and particulate load. In many cases, the water's composition significantly exceeds World Health Organization (WHO) drinking water standards. The degree of pollution depends upon: (1) ash plume direction and (2) ash plume density. The potential negative health impacts are a function of the water's pH, which regulates the elements and their chemical form that are released into drinking water. Copyright © 2012 Elsevier B.V. All rights reserved.

  16. Characterization of bottom-sediment, water, and elutriate chemistry at selected stations at Reelfoot Lake, Tennessee

    Science.gov (United States)

    Broshears, R.E.

    1991-01-01

    To better-understand and predict the potential effect of dredging on water quality at Reelfoot Lake, chemical analyses were conducted on samples of lake water, bottom sediment, and elutriate water. Chemical analyses were conducted on samples of lake water, bottom sediment, and elutriate water collected at five stations in the lake during November 1988. Lake water was of the calcium magnesium bicarbonate type with an average dissolved-solids concentration of 120 milligrams per liter. Trace constituents were present in bottom sediments at concentrations representative of their average relative abundance in the earth?s crust. Elutriate waters prepared by mixing bottom sediment and lake water had suspended-solids concentrations as high as 2,000 milligrams per liter which exerted significant oxygen demand Trace constituents in the unfiltered elutriate waters were elevated with respect to lake water; elevated concentrations were attributable to the increased suspended-solids concentrations. Concentrations of total-recoverable copper, lead., and zinc in many elutriate waters exceeded U.S. Environmental Protection Agency?s water-quality criteria for the protection of freshwater aquatic life. The toxicity of elutriate waters, as measured by a 48-hour bioassay with Ceriodaphnia dubia, was low.

  17. Responses of soil and water chemistry to mountain pine beetle induced tree mortality in Grand County, Colorado, USA

    Science.gov (United States)

    Clow, David W.; Rhoades, Charles; Briggs, Jenny S.; Caldwell, Megan K.; Lewis, William M.

    2011-01-01

    Pine forest in northern Colorado and southern Wyoming, USA, are experiencing the most severe mountain pine beetle epidemic in recorded history, and possible degradation of drinking-water quality is a major concern. The objective of this study was to investigate possible changes in soil and water chemistry in Grand County, Colorado in response to the epidemic, and to identify major controlling influences on stream-water nutrients and C in areas affected by the mountain pine beetle. Soil moisture and soil N increased in soils beneath trees killed by the mountain pine beetle, reflecting reduced evapotranspiration and litter accumulation and decay. No significant changes in stream-water NO3-">NO3- or dissolved organic C were observed; however, total N and total P increased, possibly due to litter breakdown or increased productivity related to warming air temperatures. Multiple-regression analyses indicated that % of basin affected by mountain pine beetles had minimal influence on stream-water NO3-">NO3- and dissolved organic C; instead, other basin characteristics, such as percent of the basin classified as forest, were much more important.

  18. The major and trace element chemistry of fish and lake water within ...

    African Journals Online (AJOL)

    Chemical elements in lake water are incorporated into fish tissues through bioconcentration and biomagnification. Lake water and fish tissue samples from 23 lakes, located within 4 major South African catchments, were analysed to investigate the link between element concentrations in lake water and otolith, fin spine, ...

  19. Waterflood surveillance

    Energy Technology Data Exchange (ETDEWEB)

    Ghauri, W.K.

    1976-01-01

    Surveillance, in order for it to be effective, should be implemented through an organization with adequate staffing and technology. Engineering and field operations organizations should be complementary, providing for specific lines of communications, and yet at the same time encouraging informal personal exchanges between both groups. Surveillance of a waterflood project requires constant cooperation between the 2 groups in order to collect, document, and analyze an immense quantity of data, and to conduct an efficient operation. As is customary in many oil-field operations, project well reviews are held periodically to determine if the wells are performing satisfactorily. The periodic well review is an integral part of flood surveillance and is a highly practical method of (1) keeping ahead of a waterflood project, instead of continually putting out brush fires, and (2) bringing together the expertise of the engineering, field operations, and well analysis groups in an action-oriented session. Surveillance techniques and procedures are described, but the author states that there is no cookbook technique for flood surveillance. It is laborious, detailed work, and oftentimes, with little glamour. Its rewards are evident in successful project performance, prevention of loss of anticipated reserves, and addition of reserves not forseen previously.

  20. Pore-water chemistry from the ICDP-USGS coer hole in the Chesapeake Bay impact structure--Implications for paleohydrology, microbial habitat, and water resources

    Science.gov (United States)

    Sanford, Ward E.; Voytek, Mary A.; Powars, David S.; Jones, Blair F.; Cozzarelli, Isabelle M.; Eganhouse, Robert P.; Cockell, Charles S.

    2009-01-01

    We investigated the groundwater system of the Chesapeake Bay impact structure by analyzing the pore-water chemistry in cores taken from a 1766-m-deep drill hole 10 km north of Cape Charles, Virginia. Pore water was extracted using high-speed centrifuges from over 100 cores sampled from a 1300 m section of the drill hole. The pore-water samples were analyzed for major cations and anions, stable isotopes of water and sulfate, dissolved and total carbon, and bioavailable iron. The results reveal a broad transition between fresh and saline water from 100 to 500 m depth in the post-impact sediment section, and an underlying syn-impact section that is almost entirely filled with brine. The presence of brine in the lowermost post-impact section and the trend in the dissolved chloride with depth suggest a transport process dominated by molecular diffusion and slow, compaction-driven, upward flow. Major ion results indicate residual effects of diagenesis from heating, and a pre-impact origin for the brine. High levels of dissolved organic carbon (6-95 mg/L) and the distribution of electron acceptors indicate an environment that may be favorable for microbial activity throughout the drilled section. The concentration and extent of the brine is much greater than had previously been observed, suggesting its occurrence may be common in the inner crater. However, groundwater flow conditions in the structure may reduce the salt-water-intrusion hazard associated with the brine.

  1. Research in physical chemistry and chemical education: Part A: Water Mediated Chemistry of Oxidized Atmospheric Compounds Part B: The Development of Surveying Tools to Determine How Effective Laboratory Experiments Contribute to Student Conceptual Understanding

    Science.gov (United States)

    Maron, Marta Katarzyna

    This dissertation is a combination of two research areas, experimental physical chemistry, Chapters I to V, and chemical education, Chapters VI to VII. Chapters I to V describe research on the water-mediated chemistry of oxidized atmospheric molecules and the impact that water has on the spectra of these environmental systems. The role of water in the Earth's atmosphere has been of considerable interest due to its ability to impact chemistry and climate. Oxidized atmospheric molecules in the presence of water have the ability to form hydrogen bonded water complexes. The spectroscopic investigation of nitric acid-water complexes, outlined in Chapter III, was undertaken to characterize intermolecular hydrogen bonds in a water-restricted environment at ambient temperatures. Additionally, this characterization of nitric acid-water complexes allowed for the comparison of calculated overtone OH-stretching vibrational band frequencies, intensities, and anharmonicities of intermolecular hydrogen-bonded water complexes with experimental observations. Oxidized organic molecules, such as aldehydes and ketones, in addition to forming hydrogen-bonded water complexes can undergo a hydration reaction of the carbonyl group and form germinal diols in the presence of water. This chemistry has been studied extensively in bulk aqueous media, however little is known about this process in the gas-phase at low water concentrations. The focus of the studies outlined in Chapters IV and V is motivated by the ability of pyruvic acid and formaldehyde to form germinal diols and water complexes in water-restricted environment. This water-mediated chemistry changes the physical and chemical properties of these organic molecules, therefore, impacting the partitioning between gas and particle phase, as well as the chemistry and photochemistry of oxidized organic molecules in the Earth's atmosphere. The results presented in this dissertation may help resolve the significant discrepancy between

  2. Disinfection action of electrostatic versus steric-stabilized silver nanoparticles on E. coli under different water chemistries.

    Science.gov (United States)

    Fauss, Emma K; MacCuspie, Robert I; Oyanedel-Craver, Vinka; Smith, James A; Swami, Nathan S

    2014-01-01

    The capping layer stabilizing silver nanoparticles (AgNPs) affects its aggregation, dissolution, and net disinfection action, especially under conditions of varying water composition, such as, pH, ionic strength and organic matter content. Herein, we correlate the silver ion (Ag(+)) release and reactive oxygen species (ROS) generation rates for AgNPs of varying functionalization to their net disinfection coefficient on Escherichia coli, under conditions of differing water chemistries. For electrostatically stabilized citrate-capped AgNPs, the rate of ROS generation, as measured using a fluorescent dye, is found to dominate over that of Ag(+) release, especially for smaller sized AgNP suspensions (~10nm) at low pH (~6.2). For these AgNPs, the ROS disinfection mechanism is confirmed to dominate net disinfection action, as measured by the live/dead assay, especially at low levels of organic matter. Steric stabilization of AgNPs by protein or starch-capped layers enables disinfection through reducing AgNP aggregation and promoting silver dissolution over ROS generation. We suggest the involvement of protons and dissolved oxygen in causing the independent formation of Ag(+) and ROS, regardless of the AgNP capping layer. While protein-capping layers effectively stabilize AgNPs, the generated ROS is likely dissipated by interference with the bulky capping layer, whereas the interference is lower with citrate-capping layers. Steric stabilization of AgNPs enables disinfection within a wide range of water chemistries, whereas effective disinfection can occur under electrostatic stabilization, only at low NaCl (<1 mmol/L) and organic matter (<5 mg/L) levels. Copyright © 2013 Elsevier B.V. All rights reserved.

  3. A mobile and self-sufficient lab for high frequency measurements of stable water isotopes and chemistry of multiple water sources

    Science.gov (United States)

    Windhorst, David; Kraft, Philipp; Holly, Hartmut; Sahraei, Amir; Breuer, Lutz

    2017-04-01

    Technical advances over the last years have made instruments for stable water isotope and water chemistry measurements smaller, more durable and energy efficient. It is nowadays feasible to deploy such instruments in situ during field campaigns. Coupled to an automated sample delivery system, high temporal resolution online measurements of various sources are within the bounds of economic and technical possibility. However, the day to day operation of such equipment still requires either a lot of man power and infrastructure or the implementation of a quasi-self-sufficient system. The challenge remains on how to facilitate and remotely operate such a system. We present the design and implementation of the Water Analysis Trailer for Environmental Research (WATER), an autonomous platform consisting of instruments for stable water isotope and water chemistry analysis. The system takes and measures samples in high temporal resolution (self-sufficient power supply, - automated sample delivery and preparation, and - autonomous measurements and management interfacing all instruments. In addition to the basic requirements we implemented: - communication of all system states, alarm messages and measurement results to an internal as well as an external database via cellular telemetry, - automated storage of up to 300 frozen reference samples (100 mL, stored at -18°C), - climate control for temperature sensitive equipment (±1°C), - a local and remote (up to 20 km using radio telemetry) sensor network (i.e. to record states of the hydrological system and climate and soil conditions), also suitable to trigger specific measurements - automatic fire suppression and security system. The initial instrumentation includes a UV spectrometer (ProPs, Trios GmBH, Germany) to measure NO3-, COD, TOC and total suspended sediments, multiparameter water quality probe (YSI600R, YSI, USA) to measure electrical conductivity and pH, and a stable water isotope analyzer (L2130-i, Picarro, USA

  4. Variability in the chemistry of private drinking water supplies and the impact of domestic treatment systems on water quality.

    Science.gov (United States)

    Ander, E L; Watts, M J; Smedley, P L; Hamilton, E M; Close, R; Crabbe, H; Fletcher, T; Rimell, A; Studden, M; Leonardi, G

    2016-12-01

    Tap water from 497 properties using private water supplies, in an area of metalliferous and arsenic mineralisation (Cornwall, UK), was measured to assess the extent of compliance with chemical drinking water quality standards, and how this is influenced by householder water treatment decisions. The proportion of analyses exceeding water quality standards were high, with 65 % of tap water samples exceeding one or more chemical standards. The highest exceedances for health-based standards were nitrate (11 %) and arsenic (5 %). Arsenic had a maximum observed concentration of 440 µg/L. Exceedances were also high for pH (47 %), manganese (12 %) and aluminium (7 %), for which standards are set primarily on aesthetic grounds. However, the highest observed concentrations of manganese and aluminium also exceeded relevant health-based guidelines. Significant reductions in concentrations of aluminium, cadmium, copper, lead and/or nickel were found in tap waters where households were successfully treating low-pH groundwaters, and similar adventitious results were found for arsenic and nickel where treatment was installed for iron and/or manganese removal, and successful treatment specifically to decrease tap water arsenic concentrations was observed at two properties where it was installed. However, 31 % of samples where pH treatment was reported had pH water regulations), suggesting widespread problems with system maintenance. Other examples of ineffectual treatment are seen in failed responses post-treatment, including for nitrate. This demonstrates that even where the tap waters are considered to be treated, they may still fail one or more drinking water quality standards. We find that the degree of drinking water standard exceedances warrant further work to understand environmental controls and the location of high concentrations. We also found that residents were more willing to accept drinking water with high metal (iron and manganese) concentrations than

  5. Geologic, water-chemistry, and hydrologic data from multiple-well monitoring sites and selected water-supply wells in the Santa Clara Valley, California, 1999-2003

    Science.gov (United States)

    Newhouse, M.W.; Hanson, R.T.; Wentworth, C.M.; Everett, Rhett; Williams, C.F.; Tinsley, J.C.; Noce, T.E.; Carkin, B.A.

    2004-01-01

    To better identify the three-dimensional geohydrologic framework of the Santa Clara Valley, lithologic, geologic, geophysical, geomechanical, hydraulic, and water-chemistry data were collected from eight ground-water multiple-well monitoring sites constructed in Santa Clara County, California, as part of a series of cooperative studies between the U.S. Geological Survey and the Santa Clara Valley Water District. The data are being used to update and improve the three-dimensional geohydrologic framework of the basin and to address issues related to water supply, water chemistry, sequence stratigraphy, geology, and geological hazards. This report represents a compilation of data collected from 1999 to 2003, including location and design of the monitoring sites, cone penetrometer borings, geologic logs, lithologic logs, geophysical logs, core analysis, water-chemistry analysis, ground-water-level measurements, and hydraulic and geomechanical properties from wells and core samples. Exploratory cone penetrometer borings taken in the upper 17 to 130 feet at six of the monitoring sites identified the base of Holocene as no deeper than 75 feet in the central confined area and no deeper than 35 feet in the southern unconfined areas of the valley. Generalized lithologic characterization from the monitoring sites indicates about four to six different aquifer units separated by relatively fine-grained units occur within the alluvial deposits shallower than 860 feet deep. Analysis of geophysical logs indicates that coarse-grained units varied in thickness between 10 and 25 feet in the southeastern unconfined area of the valley and between 50 and 200 feet in the south-central and southwestern areas of the valley. Deviations from temperature-gradient logs indicate that the majority of horizontal ground-water flow occurs above a depth of 775 feet in the south central and above 510 feet in the southeastern areas of the valley. Bulk physical properties from more than 1,150 feet of

  6. Comparison of surface water chemistry and weathering effects of two lake basins in the Changtang Nature Reserve, China.

    Science.gov (United States)

    Wang, Rui; Liu, Zhaofei; Jiang, Liguang; Yao, Zhijun; Wang, Junbo; Ju, Jianting

    2016-03-01

    The geochemistry of natural waters in the Changtang Nature Reserve, northern Tibet, can help us understand the geology of catchments, and provide additional insight in surface processes that influence water chemistry such as rock weathering on the Qinghai-Tibet Plateau. However, severe natural conditions are responsible for a lack of scientific data for this area. This study represents the first investigation of the chemical composition of surface waters and weathering effects in two lake basins in the reserve (Lake Dogaicoring Qiangco and Lake Longwei Co). The results indicate that total dissolved solids (TDS) in the two lakes are significantly higher than in other gauged lakes on the Qinghai-Tibet Plateau, reaching 20-40g/L, and that TDS of the tectonic lake (Lake Dogaicoring Qiangco) is significantly higher than that of the barrier lake (Lake Longwei Co). Na(+) and Cl(-) are the dominant ions in the lake waters as well as in the glacier-fed lake inflows, with chemical compositions mainly affected by halite weathering. In contrast, ion contents of inflowing rivers fed by nearby runoff are lower and concentrations of dominant ions are not significant. Evaporite, silicate, and carbonate weathering has relatively equal effects on these rivers. Due to their limited scope, small streams near the lakes are less affected by carbonate than by silicate weathering. Copyright © 2015. Published by Elsevier B.V.

  7. The influence of EI-21 redox ion-exchange resins on the secondary-coolant circuit water chemistry of vehicular nuclear power installations

    Science.gov (United States)

    Moskvin, L. N.; Rakov, V. T.

    2015-06-01

    The results obtained from testing the secondary-coolant circuit water chemistry of full-scale land-based prototype bench models of vehicular nuclear power installations equipped with water-cooled water-moderated and liquid-metal reactor plants are presented. The influence of copper-containing redox ionexchange resins intended for chemically deoxygenating steam condensate on the working fluid circulation loop's water chemistry is determined. The influence of redox ion-exchange resins on the water chemistry is evaluated by generalizing an array of data obtained in the course of extended monitoring using the methods relating to physicochemical analysis of the quality of condensate-feedwater path media and the methods relating to metallographic analysis of the state of a faulty steam generator's tube system surfaces. The deoxygenating effectiveness of the normal state turbine condensate vacuum deaeration system is experimentally determined. The refusal from applying redox ion-exchange resins in the condensate polishing ion-exchange filters is formulated based on the obtained data on the adverse effect of copper-containing redox ionexchange resins on the condensate-feedwater path water chemistry and based on the data testifying a sufficient effect from using the normal state turbine condensate vacuum deaeration system. Data on long-term operation of the prototype bench model of a vehicular nuclear power installation without subjecting the turbine condensate to chemical deoxygenation are presented.

  8. Effect-directed analysis of environmental water : combined approach of chemistry, biology, and statistics

    OpenAIRE

    Hug, Christine

    2016-01-01

    Numerous anthropogenic micropollutants were detected in surface water in the last years. Though, little is known about cause-effect relationships between chemical pollution and adverse effects on the ecosystem.Therefore, this thesis aimed to develop, apply, and evaluate methods to characterize the chemical composition of surface water and to detect adverse effects of surface water on organism. In order to promote the establishment of cause-effect relationships between chemical exposure and ad...

  9. Pore water chemistry in a disturbed and an undisturbed peat forests in Brunei Darussalam: Nutrient and carbon contents

    Science.gov (United States)

    Gandois, L.; Cobb, A.; Abu Salim, K.; Chieng Hei, I.; Lim Biaw Leng, L.; Corlett, R.; Harvey, C.

    2010-12-01

    Tropical peat swamp forests in their natural state are important reservoir of biodiversity, carbon and water. However, they are rapidly vanishing due to agricultural conversion (mainly to oil palms), logging, drainage and fire. Peat swamp forests constitute an important contribution to global and regional biodiversity, providing an habitat to rare and threatened species. They encompass a sequence of forest types from the perimeter to the center of mildely elevated domes, and at our site in Brunei, are host to Shorea Albida trees (Anderson, 1983). They constitute a large terrestrial carbon reservoir (tropical peat soils contain up to 70 Pg C, which accounts for 20% of global peat soil carbon and 2% of the global soil carbon (Hirano et al., 2007)). In tropical peat swamp forests, the most important factors controling organic matter accumulation, as well as the biodiversity and structure of the forest, are hydrology and nutrients availability (Page et al., 1999). Study of pore water in peat swamp forest can provide key information on carbon cycle, including biomass production, organic matter decomposition and leaching of carbon in draining water. However, data on pore water chemistry and nutrient concentrations in pristine tropical peatlands, as well as the effect of forest exploitation are scarce. The study area is located in the Belait district in Brunei Darussalam in Borneo Island. Brunei is perhaps the best of the regional guardians of peat forest systems; potentially irreversible damage to peat forest ecosystems has been widespread elsewhere. Two sites, one pristine dome and a logging concession, are being investigated. In order to assess the chemical status of the peat soil, pore water is sampled at different depth along the dome radius. The chemistry of pore water, including pH, conductivity, dissolved oxygen, concentration of major elements, as well as organic carbon content and properties are analyzed. References: Anderson, 1983. The tropical peat swamp of

  10. Medium pressure boiler water chemistry optimization using neutralizing amines mixture reagent AMINAT™ PK-2 at CEPP “Borovichi Refractories Plant” of JSC “BKO”

    Science.gov (United States)

    Guseva, O. V.; Butakova, M. V.; Orlov, K. A.; Vinogradov, S. V.; Pavlenko, L. S.

    2017-11-01

    An overview of the neutralizing amine based reagent AMINAT PK-2 usage for water chemistry of steam boilers for medium pressure boiler was given. Long term experiment showed that new reagent allows to decrease corrosion rate comparing with old water chemistry based on ammonia only. Two dosage schemes in different cycle places discussed. Scheme with two points on injection showed better results. Results of corrosion rates experiments and photos of tubes inner surfaces are presented. Based on fuel savings due to reducing scale formation the total annual economy for last year was 5.1 million Russian roubles.

  11. Pore-water chemistry from the ICDP-USGS core hole in the Chesapeake Bay impact structure-Implications for paleohydrology, microbial habitat, and water resources

    Science.gov (United States)

    Sanford, W.E.; Voytek, M.A.; Powars, D.S.; Jones, B.F.; Cozzarelli, I.M.; Cockell, C.S.; Eganhouse, R.P.

    2009-01-01

    We investigated the groundwater system of the Chesapeake Bay impact structure by analyzing the pore-water chemistry in cores taken from a 1766-m-deep drill hole 10 km north of Cape Charles, Virginia. Pore water was extracted using high-speed centrifuges from over 100 cores sampled from a 1300 m section of the drill hole. The pore-water samples were analyzed for major cations and anions, stable isotopes of water and sulfate, dissolved and total carbon, and bioavailable iron. The results reveal a broad transition between freshwater and saline water from 100 to 500 m depth in the postimpact sediment section, and an underlying synimpact section that is almost entirely filled with brine. The presence of brine in the lowermost postimpact section and the trend in dissolved chloride with depth suggest a transport process dominated by molecular diffusion and slow, compaction-driven, upward flow. Major ion results indicate residual effects of diagenesis from heating, and a pre-impact origin for the brine. High levels of dissolved organic carbon (6-95 mg/L) and the distribution of electron acceptors indicate an environment that may be favorable for microbial activity throughout the drilled section. The concentration and extent of the brine is much greater than had previously been observed, suggesting that its occurrence may be common in the inner crater. However, groundwater-flow conditions in the structure may reduce the saltwater-intrusion hazard associated with the brine. ?? 2009 The Geological Society of America.

  12. An inorganic water chemistry dataset (1972–2011) of rivers, dams ...

    African Journals Online (AJOL)

    2013-03-28

    Mar 28, 2013 ... A national dataset of inorganic chemical data of surface waters (rivers, lakes, and dams) in South Africa is presented and made freely available. The dataset comprises more than 500 000 complete water analyses from 1972 up to 2011, collected from more than 2 000 sample monitoring stations in South ...

  13. Infiltration from an impoundment for coal-bed natural gas, Powder River Basin, Wyoming: Evolution of water and sediment chemistry

    Science.gov (United States)

    Healy, R.W.; Rice, C.A.; Bartos, T.T.; McKinley, M.P.

    2008-01-01

    Development of coal-bed natural gas (CBNG) in the Powder River Basin, Wyoming, has increased substantially in recent years. Among environmental concerns associated with this development is the fate of groundwater removed with the gas. A preferred water-management option is storage in surface impoundments. As of January 2007, permits for more than 4000 impoundments had been issued within Wyoming. A study was conducted on changes in water and sediment chemistry as water from an impoundment infiltrated the subsurface. Sediment cores were collected prior to operation of the impoundment and after its closure and reclamation. Suction lysimeters were used to collect water samples from beneath the impoundment. Large amounts of chloride (12,300 kg) and nitrate (13,500 kg as N), most of which accumulated naturally in the sediments over thousands of years, were released into groundwater by infiltrating water. Nitrate was more readily flushed from the sediments than chloride. If sediments at other impoundment locations contain similar amounts of chloride and nitrate, impoundments already permitted could release over 48 x 106 kg of chloride and 52 x 106 kg of nitrate into groundwater in the basin. A solute plume with total dissolved solid (TDS) concentrations at times exceeding 100,000 mg/L was created in the subsurface. TDS concentrations in the plume were substantially greater than those in the CBNG water (about 2300 mg/L) and in the ambient shallow groundwater (about 8000 mg/L). Sulfate, sodium, and magnesium are the dominant ions in the plume. The elevated concentrations are attributed to cation-exchange-enhanced gypsum dissolution. As gypsum dissolves, calcium goes into solution and is exchanged for sodium and magnesium on clays. Removal of calcium from solution allows further gypsum dissolution.

  14. Long Term Water Level and Chemistry Evolution in Groundwater of the Mississippi Embayment, Arkansas, USA: Preliminary Results

    Science.gov (United States)

    Neumann, K.; Dowling, C. B.; Moraru, C.; Hannigan, R. E.

    2008-12-01

    The Mississippi Embayment, located in the southeastern U.S., is a syncline formed by the northward excursion of the Gulf of Coastal Plain. Structurally, the Mississippi Embayment is a hydrogeological basin consisting of six regional aquifers. These productive aquifers yield good-quality waters. The Mississippi Embayment Regional Ground Water Study group located at Arkansas State University compiled and organized the available water chemistry and groundwater level data from the USGS groundwater monitoring database. The uppermost unconfined horizon forms the Mississippi River Valley Alluvial Aquifer (ALVM), one of the largest unconfined aquifers in the world. The Holocene and Pleistocene ALVM is formed from sand, gravel, and loess. The majority of the groundwater wells (approximately 80%) are drilled in the ALVM. As the groundwater levels have fallen in the unconfined ALVM, more groundwater wells are drilled in the deeper aquifers-the Upper, Middle, and Lower Claiborne Aquifers. The Ecocene Upper Claiborne Aquifer protolith is sand, silt, and clay while the Eocene Middle Claiborne and Lower Claiborne aquifers are sand and minor clay. We focused our investigation of the spatial and temporal evolution of groundwater in the Arkansas section of the Mississippi Embayment by using wells with long term monitoring records (1928 - 2005). Overall, the groundwater levels of the unconfined aquifer (ALVM) have decreased; we have not yet evaluated the lower aquifer water level changes. Attention was paid to rock-water interactions along flowpaths in the ALVM and Upper Claiborne aquifers, and to temporal changes at specific sampling sites. The study is utilizing groundwater pH, cation, anion, and nutrient data in the programs AquaChem and PHREEQE to describe mineral and CO2 saturations in groundwater. First results indicate that the modeling allows the identification of different processes (CO2 pressure, calcite saturation) that control distinct geochemical provinces, e.g. urban

  15. Surveillance of surgical site infections by Pseudomonas aeruginosa and strain characterization in Tanzanian hospitals does not provide proof for a role of hospital water plumbing systems in transmission.

    Science.gov (United States)

    Moremi, Nyambura; Claus, Heike; Vogel, Ulrich; Mshana, Stephen E

    2017-01-01

    The role of hospital water systems in the development of Pseudomonas aeruginosa (P. aeruginosa) surgical site infections (SSIs) in low-income countries is barely studied. This study characterized P. aeruginosa isolates from patients and water in order to establish possible epidemiological links. Between December 2014 and September 2015, rectal and wound swabs, and water samples were collected in the frame of active surveillance for SSIs in the two Tanzanian hospitals. Typing of P. aeruginosa was done by multi-locus sequence typing. Of 930 enrolled patients, 536 were followed up, of whom 78 (14.6%, 95% CI; 11.6-17.5) developed SSIs. P. aeruginosa was found in eight (14%) of 57 investigated wounds. Of the 43 water sampling points, 29 were positive for P. aeruginosa. However, epidemiological links to wound infections were not confirmed. The P. aeruginosa carriage rate on admission was 0.9% (8/930). Of the 363 patients re-screened upon discharge, four (1.1%) possibly acquired P. aeruginosa during hospitalization. Wound infections of the three of the eight P. aeruginosa SSIs were caused by a strain of the same sequence type (ST) as the one from intestinal carriage. Isolates from patients were more resistant to antibiotics than water isolates. The P. aeruginosa SSI rate was low. There was no evidence for transmission from tap water. Not all P. aeruginosa SSI were proven to be endogenous, pointing to other routes of transmission.

  16. Hydrology and water chemistry of shallow aquifers along the upper Clark Fork, western Montana

    Science.gov (United States)

    Nimick, D.A.

    1993-01-01

    Shallow ground-water resources in western Montana have been developed primarily in Quaternary alluvium and Tertiary deposits, although bedrock supplies water to wells locally. Well-yield and trans- missivity values were largest (medians of 40 gallons per minute and 970 feet squared per day, respec- tively) in alluvium and smallest (medians of 15 gallons per minute and 130 feet squared per day, respectively) in bedrock. Chemical composition of ground water was dominated by calcium, magnesium, and bicarbonate derived from dissolution of carbonate minerals. Other water types may be the result of ion exchange (increased sodium) and mixing of geothermal water or leachate from mine wastes (increased sulfate). Although concen- trations of arsenic were relatively small (maximum of 20 micrograms per liter), they were somewhat larger in alluvium within 300 feet of the Clark Fork. Elevated concentrations of cadmium (maximum of 6 micrograms per liter) were measured in water from one well downgradient from tailings ponds. Although mining and smelting activities have resulted in widespread distribution of contami- nants in the Clark Fork valley, this study indicates that ground water contains elevated concentrations of trace elements only locally. Streamflow data indicate significant ground-water inflow to the Clark Fork in two reaches. Between Racetrack and Garrison, irrigation-return flow probably augments naturally occurring ground-water discharge. Between Jens and Cramer Creek, geo- thermal water from bedrock flows through alluvium to the river. In the Clark Fork, the maximum arsenic concentration was 8.1 micrograms per liter; copper and manganese concentrations were largest at Warm Springs (maximums of 14 and 350 micrograms per liter, respectively) and decreased downstream.

  17. Surveillance Angels

    NARCIS (Netherlands)

    Rothkrantz, L.J.M.

    2014-01-01

    The use of sensor networks has been proposed for military surveillance and environmental monitoring applications. Those systems are composed of a heterogeneous set of sensors to observe the environment. In centralised systems the observed data will be conveyed to the control room to process the

  18. National Coral Reef Monitoring Program: Water Chemistry of the Coral Reefs in American Samoa from Water Samples collected since 2015

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Water samples are collected and analyzed to assess spatial and temporal variation in the seawater carbonate systems of coral reef ecosystems in the Hawaiian and...

  19. Theoretical investigations of metallic surfaces for water chemistry; Theoretische Untersuchungen metallischer Oberflaechen fuer die Wasserstoffchemie

    Energy Technology Data Exchange (ETDEWEB)

    Schnur, Sebastian

    2010-11-19

    Properties of the metal-water interface have been addressed by periodic density functional theory calculations, in particular with respect to the electronic and geometric structures of water bilayers on several transition metal surfaces. The structure and the vibrational spectra of water bilayers at room temperatures have been studied performing ab initio molecular dynamics simulations. In order to model varying electrode potentials, an explicite counter electrode has been implemented in a periodic density functional theory code, and first preliminary results using this implementation will be presented. (orig.)

  20. Effect of pore water chemistry on anisotropic behavior of clayey soil and possible application in underground construction

    Directory of Open Access Journals (Sweden)

    Jinchun Chai

    2016-12-01

    Full Text Available The effect of pore water chemistry on anisotropic behavior of consolidation and shear strength of reconstituted Ariake clay has been investigated experimentally. Two types of chemicals added into the pore water of the soil for enhancing flocculation microstructure of soil particles are sodium chloride (salt (NaCl, and calcium chloride (CaCl2; and two dispersants added are sodium triphosphate (Na5P3O10 and sodium hexametaphosphate (Na6P6O18, respectively. The concentrations of these chemicals in pore water were 2–3%. Degrees of anisotropy of the coefficient of consolidation and undrained shear strength decreased with adding NaCl and CaCl2, but increased with adding the dispersants. Degree of anisotropy also increased with one-dimensional (1D deformation and the samples with dispersive additives had higher increase rate. It has been confirmed qualitatively by scanning electron microscopy (SEM images that adding dispersive chemicals promoted the formation of dispersive microstructure and increased the degree of anisotropy, and the chemicals enhancing flocculent microstructure had an inverse effect. The possible application of the findings to underground construction has been discussed also.

  1. Trends and seasonality in stream water chemistry in two moorland catchments of the Upper River Wye, Plynlimon

    Directory of Open Access Journals (Sweden)

    B. Reynolds

    1997-01-01

    Full Text Available Stream water chemistry in the Cyff and Gwy subcatchments within the headwaters of the River Wye has been monitored regularly since 1980. In the Gwy, which is a predominantly semi-natural grassland catchment, land use has remained relatively static over the monitoring period, whilst the Cyff catchment is more buffered because of base cation inputs from agricultural improvement and ground water sources. Using a variety of statistical techniques, the long-term data are examined for evidence of trends after eliminating seasonal effects. The results highlight some of the difficulties associated with the analysis of longterm water quality data which show considerable variability over a variety of timescales. Some of this variability can be explained in terms of hydrochemical responses to climatic extremes and episodic events such as large atmospheric inputs of seasalts. The long-term fluctuations in solute concentration underline the continuing need for maintaining consistent long-term monitoring at sensitive upland sites if underlying trends related to gradual changes in pollutant deposition or climate are to be detected with any certainty.

  2. Mukilteo water sensor time series - Field work coupling measurements of carbon chemistry and distribution of free-living organisms

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — To estimate the carbon chemistry conditions experienced by free-living organisms, we will conduct coupled biological/carbon chemistry sampling for key zooplankton...

  3. Willapa NWR: Initial Survey Instructions for Tidal Restoration Monitoring - Water Chemistry

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Through an active role in local, state, and federal partnerships, the refuge staff works to maintain the ecological integrity and water quality of the Willapa Bay...

  4. NODC Standard Format Water Physics and Chemistry (F004) Data (1949-1985) (NCEI Accession 0012901)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains data from measurements and analyses of physical and chemical characteristics of the water column. Chemical parameters that may be recorded are...

  5. LBA-ECO ND-30 Water Chemistry, Rainfall Exclusion, km 67, Tapajos National Forest

    Data.gov (United States)

    National Aeronautics and Space Administration — ABSTRACT: This data set reports the results of chemical analyses of rainfall, throughfall, litter leachate, and soil water samples collected before, during, and...

  6. LBA-ECO ND-30 Water Chemistry, Rainfall Exclusion, km 67, Tapajos National Forest

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set reports the results of chemical analyses of rainfall, throughfall, litter leachate, and soil water samples collected before, during, and after a...

  7. Spatiotemporal assessment of water chemistry in intermittently open/closed coastal lakes of Southern Baltic

    Science.gov (United States)

    Astel, Aleksander M.; Bigus, Katarzyna; Obolewski, Krystian; Glińska-Lewczuk, Katarzyna

    2016-12-01

    Ionic profile, pH, electrolytic conductivity, chemical oxygen demand and concentration of selected heavy metals (Ni, Cu, Zn, Fe and Mn) were determined in water of 11 intermittently closed and open lakes and lagoons (ICOLLs) located in Polish coastline. Multidimensional data set was explored by the use of the self-organizing map (SOM) technique to avoid supervised and predictable division for fully isolated, partially and fully connected lakes. Water quality assessment based on single parameter's mean value allowed classification of majority of lakes to first or second class of purity according to regulation presenting classification approach applicable to uniform parts of surface waters. The SOM-based grouping revealed seven clusters comprising water samples of similar physico-chemical profile. Fully connected lakes were characterized by the highest concentration of components characteristic for sea salts (NaCl, MgCl2, MgSO4, CaSO4, K2SO4 and MgBr2), however spring samples from Łebsko were shifted to another cluster suggesting that intensive surface run-off and fresh-water inflow through Łupawa river decreases an impact of sea water intrusions. Forecasted characteristic of water collected in Resko Przymorskie lake was disturbed by high contamination by nitrites indicating accidental and local contamination due to usage of sodium nitrite for the curing of meat. Some unexpected sources of contamination was discovered in intermittently open and closed lakes. Presumably Zn contamination is due to use of wood preservatives to protect small wooden playgrounds or camping places spread around one of the lake, while increased concentration of Ni could be connected with grass and vegetation burning. Waters of Jamno lake are under the strongest anthropogenic impact due to inefficient removal of phosphates by waste water treatment plant and contamination by Fe and Mn caused by backwashing of absorption filters. Generally, the quality of ICOLLs' water was diversified, while

  8. Monitoring of heavy metal load - by mosses or rain water chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Ruoho-Airola, T. [Finnish Meteorological Inst., Helsinki (Finland); Maekelae, K. [National Board of Waters and the Environment, Helsinki (Finland)

    1995-12-31

    The deposition of heavy metals is usually determined from precipitation chemistry but the moss technique has been increasingly used, particularly in the Nordic countries. Some international monitoring programmes, e.g. UN/ECE Integrated Monitoring, give them as alternative methods. However, their comparability has not been sufficiently determined. This study compares the two monitoring methods for Pb, Cd, Cu and Zn, which have different sources. The metal industry is an important source of Pb and Cd emissions. Long- range transport as well as traffic and local emissions are also important sources for Pb. The use of fertilizers and fossil fuels also result in Cd emissions. Cu and Zn are emitted from metal industries and local sources. Unlike Pb and Cd, Cu and Zn are essential elements for living organisms. Cu and Zn are needed in many enzymes and Zn in proteins. Mosses are thought to take all their nutrients from the air. The deposition of heavy metals is also effectively retained by mosses and may be used to indicate levels of heavy metal deposition. In northern countries the mosses are isolated from air (and therefore also from deposition) by snow in winter. In this study both the bulk deposition of the whole year (later `total deposition`) and the bulk deposition of the snow-free period (later `bare ground deposition`) are compared to the metal concentrations in mosses. (author)

  9. Surface chemistry of rare-earth oxide surfaces at ambient conditions: reactions with water and hydrocarbons

    Science.gov (United States)

    Külah, Elçin; Marot, Laurent; Steiner, Roland; Romanyuk, Andriy; Jung, Thomas A.; Wäckerlin, Aneliia; Meyer, Ernst

    2017-03-01

    Rare-earth (RE) oxide surfaces are of significant importance for catalysis and were recently reported to possess intrinsic hydrophobicity. The surface chemistry of these oxides in the low temperature regime, however, remains to a large extent unexplored. The reactions occurring at RE surfaces at room temperature (RT) in real air environment, in particular, in presence of polycyclic aromatic hydrocarbons (PAHs), were not addressed until now. Discovering these reactions would shed light onto intermediate steps occurring in automotive exhaust catalysts before reaching the final high operational temperature and full conversion of organics. Here we first address physical properties of the RE oxide, nitride and fluoride surfaces modified by exposure to ambient air and then we report a room temperature reaction between PAH and RE oxide surfaces, exemplified by tetracene (C18H12) on a Gd2O3. Our study evidences a novel effect - oxidation of higher hydrocarbons at significantly lower temperatures (~300 K) than previously reported (>500 K). The evolution of the surface chemical composition of RE compounds in ambient air is investigated and correlated with the surface wetting. Our surprising results reveal the complex behavior of RE surfaces and motivate follow-up studies of reactions between PAH and catalytic surfaces at the single molecule level.

  10. The spatial variability of water chemistry and DOC in bog pools: the importance of slope position, diurnal turnover and pool type

    Science.gov (United States)

    Holden, Joseph; Turner, Ed; Baird, Andy; Beadle, Jeannie; Billett, Mike; Brown, Lee; Chapman, Pippa; Dinsmore, Kerry; Dooling, Gemma; Grayson, Richard; Moody, Catherine; Gee, Clare

    2017-04-01

    We have previously shown that marine influence is an important factor controlling regional variability of pool water chemistry in blanket peatlands. Here we examine within-site controls on pool water chemistry. We surveyed natural and artificial (restoration sites) bog pools at blanket peatland sites in northern Scotland and Sweden. DOC, pH, conductivity, dissolved oxygen, temperature, cations, anions and absorbance spectra from 220-750nm were sampled. We sampled changes over time but also conducted intensive spatial surveys within individual pools and between pools on the same sampling days at individual study sites. Artificial pools had significantly greater DOC concentrations and different spectral absorbance characteristics when compared to natural pools at all sites studied. Within-pool variability in water chemistry tended to be small, even for very large pools ( 400 m2), except where pools had a layer of loose, mobile detritus on their beds. In these instances rapid changes took place between the overlying water column and the mobile sediment layer wherein dissolved oxygen concentrations dropped from values of around 12-10 mg/L to values less than 0.5 mg/L over just 2-3 cm of the depth profile. Such strong contrasts were not observed for pools which had a hard peat floor and which lacked a significant detritus layer. Strong diurnal turnover occurred within the pools on summer days, including within small, shallow pools (e.g. control on several pool water chemistry variables including pH and DOC concentration with accumulation (higher concentrations) in pools that were located further downslope in both natural and artificial pool systems. These processes have important implications for our interpretation of water chemistry and gas flux data from pool systems, how we design our sampling strategies and how we upscale results.

  11. Aespoe Hard Rock Laboratory. Prototype repository. Analyses of microorganisms, gases, and water chemistry in buffer and backfill, 2010

    Energy Technology Data Exchange (ETDEWEB)

    Lydmark, Sara [Microbial Analytics Sweden AB, Moelnlycke (Sweden)

    2011-06-15

    The prototype repository (hereafter, 'Prototype') is an international project to build and study a fullscale model of the planned Swedish final repository for spent nuclear fuel. However, the Prototype differs from a real storage in that it is drained, which makes the swelling pressure lower in the Prototype than in a real storage facility. The heat from the radioactive decay is simulated by electrical heaters. The project is being conducted at the Aespoe Hard Rock Laboratory (HRL) in crystalline rock at a depth of approximately 450 m. A monitoring programme is investigating the evolution of the water chemistry, gas, and microbial activity at the site, and a specific aim is to monitor the microbial consumption of oxygen in situ in the Prototype. This document describes the results of the analyses of microbes, gases, and chemistry inside the Prototype in 2010. Hydrogen, helium, nitrogen, oxygen, carbon monoxide, carbon dioxide, methane, ethane, and ethene were analysed at the following sampling points in the Prototype: KBU10001, KBU10002, KBU10004, KBU10008, and KFA04. Where the sampling points in the Prototype delivered pore water, the water was analysed for amount of ATP (i.e. the biovolume), culturable heterotrophic aerobic bacteria (CHAB), sulphate-reducing bacteria (SRB), methane-oxidizing bacteria (MOB), and iron-reducing bacteria (IRB). The pore water collected from the Prototype was subject to as many chemical analyses as the amount of water allowed. Chemical analyses were also performed on pore water from two additional sampling points, KBU10005 and KBU10006. Chemical data from a previous investigation of the groundwater outside the Prototype were compared with the pore water chemistry. The improved sampling and analysis protocols introduced in 2007 worked very well. The International Progress Report (IPR) 08-01 (Eriksson 2008) revealed that many of the hydrochemical sampling points differ greatly from each other. The 16 sampling points were

  12. Water-chemistry data collected in and near Kaloko-Honokohau National Historical Park, Hawaii, 2012–2014

    Science.gov (United States)

    Tillman, Fred D; Oki, Delwyn S.; Johnson, Adam G.

    2014-01-01

    Kaloko-Honokōhau National Historical Park (KAHO) on western Hawaiʻi was established in 1978 to preserve, interpret, and perpetuate traditional Native Hawaiian culture and activities, including the preservation of a variety of culturally and ecologically significant water resources that are vital to this mission. KAHO water bodies provide habitat for 1 threatened, 11 endangered, and 3 candidate threatened or endangered species. These habitats are sustained by, and in the case of ʻAimakapā Fishpond and the anchialine pools, entirely dependent on, groundwater from the Keauhou aquifer system. Development of inland impounded groundwater in the Keauhou aquifer system may affect the coastal freshwater-lens system on which KAHO depends, if the inland impounded-groundwater and coastal freshwater-lens systems are hydrologically connected. This report documents water-chemistry results from a U.S. Geological Survey study that collected and analyzed water samples from 2012 to 2014 from 25 sites in and near KAHO to investigate potential geochemical indicators in water that might indicate the presence or absence of a hydrologic connection between the inland impounded-groundwater and coastal freshwater-lens systems in the area. Samples were collected under high-tide and low-tide conditions for KAHO sites, and in dry-season and wet-season conditions for all sites. Samples were collected from two ocean sites, two fishponds, three anchialine pools, and three monitoring wells within KAHO. Two additional nearshore wells were sampled on property adjacent to and north of KAHO. Additional samples from the freshwater-lens system were collected from six inland wells located upslope from KAHO, including three production wells. Seven production wells in the inland impounded-groundwater system also were sampled. Water samples were analyzed for major ions, selected trace elements, rare-earth elements, strontium-isotope ratio, and stable isotopes of water. Precipitation samples from five

  13. Pile burning effects on soil water repellency, infiltration, and downslope water chemistry in the Lake Tahoe Basin, USA

    Science.gov (United States)

    Ken Hubbert; Matt Busse; Steven Overby; Carol Shestak; Ross Gerrard

    2015-01-01

    Thinning of conifers followed by pile burning has become a popular treatment to reduce fuel loads in the Lake Tahoe Basin. However, concern has been voiced about burning within or near riparian areas because of the potential effect on nutrient release and, ultimately, lake water quality. Our objective was to quantify the effects of pile burning on soil physical and...

  14. Air surveillance

    Energy Technology Data Exchange (ETDEWEB)

    Patton, G.W.

    1995-06-01

    This section of the 1994 Hanford Site Environmental Report summarizes the air surveillance and monitoring programs currently in operation at that Hanford Site. Atmospheric releases of pollutants from Hanford to the surrounding region are a potential source of human exposure. For that reason, both radioactive and nonradioactive materials in air are monitored at a number of locations. The influence of Hanford emissions on local radionuclide concentrations was evaluated by comparing concentrations measured at distant locations within the region to concentrations measured at the Site perimeter. This section discusses sample collection, analytical methods, and the results of the Hanford air surveillance program. A complete listing of all analytical results summarized in this section is reported separately by Bisping (1995).

  15. [Impact of Rocky Desertification Treatment on Underground Water Chemistry and Dissolved Inorganic Carbon Isotope in Karst Areas].

    Science.gov (United States)

    Xiao, Shi-zhen; Xiong, Kang-ning; Lan, Jia-cheng; Zhang, Hui; Yang, Long

    2015-05-01

    Five springs representing different land-use types and different karst rocky desertification treatment models were chosen at the Huajiang Karst Rocky Desertification Treatment Demonstration Site in Guanling-Zhenfeng Counties in Guizhou, to analyze the features of underground water chemistry and dissolved inorganic carbon isotopes (δ13C(DIC)) and reveal the effect of rocky desertification treatment on karstification and water quality. It was found that, the underground water type of the research area was HCO3-Ca; the water quality of the springs which were relatively less affected by human activities including Shuijingwan Spring (SJW) , Gebei Spring (GB), and Maojiawan Spring (MJW) was better than those relatively more affected by human activities including Diaojing Spring (DJ) and Tanjiazhai Spring (TJZ) , the main ion concentrations and electrical conductivity of which were higher; pH, SIc and pCO2 were sensitive to land-use types and rocky desertification treatment, which could be shown by the higher pH and SIc and lower pCO2 in MJW than those in the other four springs; (Ca(2+) + Mg2+)/HCO(3-) of SJW, MJW and GB were nearly 1:1, dominated by carbonate rock weathering by carbon acid, while the (Ca(2+) + Mg2+) of DJ and TJZ was much higher than HCO3-, suggesting that sulfate and nitrate might also dissolve carbonate rock because of the agricultural activities; δ13C(DIC) was lighter in wet season because of the higher biological activities; the average δ13C(DIC) was in the order of DJ (-12.79 per thousand) desertification and lighter after the rocky desertification are treated and controlled.

  16. PASSIVE SAMPLING OF GROUND WATER MONITORING WELLS WITHOUT PURGING MULTILEVEL WELL CHEMISTRY AND TRACER DISAPPEARANCE

    Science.gov (United States)

    It is essential that the sampling techniques utilized in groundwater monitoring provide data that accurately depicts the water quality of the sampled aquifer in the vicinity of the well. Due to the large amount of monitoring activity currently underway in the U.S.A. it is also im...

  17. The impact of urbanization on water and sediment chemistry of ephemeral forest pools

    Science.gov (United States)

    Robert T. Brooks; Suzanne D. Miller; John Newsted

    2002-01-01

    We compared the water and sediment composition of two ephemeral pools located in forested settings in a developed suburban area with two similar pools located in extensive forest in Massachusetts. We also compared the macroinvertebrate communities. The sediments of the forest pools were 100% organic material, while those of the urban pools were predominantly silt. The...

  18. Spatio-temporal variation in stream water chemistry in a tropical urban watershed

    Science.gov (United States)

    A. Ramirez; K.G. Rosas; A.E. Lugo; O.M. Ramos-Gonzalez

    2014-01-01

    Urban activities and related infrastructure alter the natural patterns of stream physical and chemical conditions. According to the Urban Stream Syndrome, streams draining urban landscapes are characterized by high concentrations of nutrients and ions, and might have elevated water temperatures and variable oxygen concentrations. Here, we report temporal and spatial...

  19. Support on water chemistry and processes for nuclear power plant auxiliary systems

    Energy Technology Data Exchange (ETDEWEB)

    Chocron, M.; Becquart, E.; La Gamma, A.M.; Schoenbrod, B. [Unidad de Actividad Quimica, Gcia. Centro Atomico Constituyentes, Comision Nacional de Energia, Buenos Aires (Argentina); Allemandi, W.; Fernandez, A.N.; Ovando, L. [Central Nuclear Embalse, Nucleoelectrica Argentina S.A. (Argentina)

    2002-07-01

    In particular PHWRs have a system devoted to the purification and upgrading of the collected heavy water leaks. The purification train is fed with different degradation ratios (D{sub 2}O/H{sub 2}O), activities and impurities. The water is distilled in a packed bed column filled with a mesh type packing. The mesh wire is made of a bronze substrate covered by copper oxides whose current composition has been determined by Moessbauer spectroscopy. With the purpose of minimizing the column stack corrosion, the water is pre-treated in a train consisting of an activated charcoal bed-strong cationic-anionic resin and a final polishing mixed bed resin. Ionic chemicals like acetic acid (whose provenance is suspected to come from the air treatment/D{sub 2}O recovery system where the regeneration is performed at high temperature) are detected by the conductivity and ion chromatography when they concentrate at the column bottom. Traces of oils are retained by the charcoal bed but some compounds extracted by the aqueous phase are suspected to be responsible for the resins fouling or precursors of potentially aggressive agents inside the distillation column. Those species have been detected and identified by gaseous chromatography-mass spectrometry (GC-MS). In the present work, the identification, evaluation of alternatives for the retention and results compared to the original products present in the water upgrading purification train have been summarized. (authors)

  20. Relationship between water chemistry and sediment mineralogy in the Cerro Prieto geothermal field: a preliminary report

    Energy Technology Data Exchange (ETDEWEB)

    Valette-Silver, J.N. (Univ. de Perpignan, France); Thompson, J.M.; Ball, J.W.

    1981-01-01

    The chemical compositions of waters collected from the Cerro Prieto geothermal production wells and hydrothermal emanations are different. Compared to the Cerro Prieto well waters, the surficial waters generally contain significantly less potassium, slightly less calcium and chloride, and significantly more magnesium and sulfate. In comparison to the unaltered sediments, the changes in the mineralogy of the altered sediments appear to be controlled by the type of emanation (well, spring, mud pot, geyser, fumarole, or cold pool). However, an increase in quartz and potassium feldspar percentages seems to be characteristic of the majority of the sediments in contact with geothermal fluids. Preliminary attempts to model the chemical processes occurring in the Cerro Prieto geothermal field using chemical equilibrium calculations are reported. For this purpose the chemical compositions of thermal waters (well and surficial emanation) were used as input data to make calculations with SOLMNEQ and WATEQ2 computer programs. Then the theoretical mineral composition of altered sediments was predicted and compared to the mineralogy actually observed in the solid samples.

  1. Danube catchment water chemistry monitoring - elemental pattern determination from source to mouth using ICP-MS

    Science.gov (United States)

    Tchaikovsky, Anastassiya; Zitek, Andreas; Irrgeher, Johanna; Prohaska, Thomas

    2014-05-01

    Monitoring the elemental composition of river water is an important tool to determine the chemical status of a river. However, currently many studies are limited to the analysis of heavy metals included in the EU Water Framework Directive Priority Substances List (Cd, Hg, Ni, Pb). Yet, the assessment of further elements (e.g. Ca, Mg, Si) can give additional relevant information for understanding catchment processes such as soil erosion, weathering, hydrological changes or glacial melting. In addition, site specific "elemental pattern" can be used as tracer for ecological studies, like habitat and migration studies of fish or birds. Elemental information is of particular interest complementary to isotopic data where only little variability in the isotopic signatures can be observed. In this work, we investigated water samples collected from 68 sampling sites along the longitudinal course of the river Danube including the major tributaries during the Joint Danube Survey 3 (JDS3) in 2013. Water samples were obtained as triplicates in the middle of the river and analyzed using Inductively Coupled - Plasma Mass Spectrometry (ICP-MS). Method validation was performed using riverine water (NRC SLRS-5) certified reference material as well as in-house prepared quality control standards. Due to the diverse geology and changing natural and anthropogenic factors along the longitudinal course of the Danube, pronounced elemental variations among the water samples were documented. For instance, especially some major elements (Ca, K, Mg, Na) together with some minor elements (Si, Sr) are known to reflect in particular regional geological morphologies. In addition, the variation in Si/Ca ratios can be used as an indicator for weathering conditions, especially in the mountainous areas along the Danube. Elevated concentrations of Cd, Cu, Fe, Ni, and Pb downstream of some large cities and industrial areas are signs of significant anthropogenic impact. In combination, the chemical

  2. Multi-linear regression models predict the effects of water chemistry on acute lead toxicity to Ceriodaphnia dubia and Pimephales promelas.

    Science.gov (United States)

    Esbaugh, A J; Brix, K V; Mager, E M; Grosell, M

    2011-09-01

    The current study examined the acute toxicity of lead (Pb) to Ceriodaphnia dubia and Pimephales promelas in a variety of natural waters. The natural waters were selected to range in pertinent water chemistry parameters such as calcium, pH, total CO(2) and dissolved organic carbon (DOC). Acute toxicity was determined for C. dubia and P. promelas using standard 48h and 96h protocols, respectively. For both organisms acute toxicity varied markedly according to water chemistry, with C. dubia LC50s ranging from 29 to 180μg/L and P. promelas LC50s ranging from 41 to 3598μg/L. Additionally, no Pb toxicity was observed for P. promelas in three alkaline natural waters. With respect to water chemistry parameters, DOC had the strongest protective impact for both organisms. A multi-linear regression (MLR) approach combining previous lab data and the current data was used to identify the relative importance of individual water chemistry components in predicting acute Pb toxicity for both species. As anticipated, the P. promelas best-fit MLR model combined DOC, calcium and pH. Unexpectedly, in the C. dubiaMLR model the importance of pH, TCO(2) and calcium was minimal while DOC and ionic strength were the controlling water quality variables. Adjusted R(2) values of 0.82 and 0.64 for the P. promelas and C. dubia models, respectively, are comparable to previously developed biotic ligand models for other metals. Copyright © 2011 Elsevier Inc. All rights reserved.

  3. Adirondack lakes survey: An interpretive analysis of fish communities and water chemistry, 1984--1987

    Energy Technology Data Exchange (ETDEWEB)

    Baker, J.P. (Baker (Joan P.), Raleigh, NC (USA)); Gherini, S.A.; Munson, R.K. (Tetra Tech, Inc., Pasadena, CA (USA)); Christensen, S.W. (Oak Ridge National Lab., TN (USA)); Driscoll, C.T. (Syracuse Univ., NY (USA)); Gallagher, J. (Adirondack Lakes Survey Corp., Ray Brook, NY (USA)); Newton, R.M. (Smith Coll., Northampton, MA (USA)); Reckhow, K.H. (Duke Univ., Durham, NC (USA)); Schofield, C.L. (Co

    1990-01-01

    The Adirondack Lakes Survey Corporation (ALSC) was formed as a cooperative effort of the New York State Department of Environmental Conservation and the Empire State Electric Energy Research Corporation to better characterize the chemical and biological status of Adirondack lakes. Between 1984 and 1987, the ALSC surveyed 1469 lakes within the Adirondack ecological zone. As a follow-up to the survey, the ALSC sponsored a series of interpretive analyses of the ALSC data base. The primary objectives of these analyses were as follows: Evaluate the influence of mineral acids (from acidic deposition) and nonmineral acids (natural organic acids) on lake pH levels; classify Adirondack lakes according to lake and watershed features expected to influence their responsiveness to changes in acidic deposition; evaluate the sensitivity of Adirondack lakes to changes in environmental conditions, such as changes in mineral acids or dissolved organic carbon concentrations; identify lake characteristics important in explaining the observed present-day status of fish communities in Adirondack lakes, in particular the relative importance of lake acidity; evaluate changes that have occurred over time in Adirondack fish communities and probable causes for these trends by using the available historical data on fish communities in the Adirondacks and the ALSC data base; and determine the degree to which the existing fish resource might be at risk from continued acidic deposition, or might recover if acidity levels were reduced. The basic approach examined relationships observed in the ALSC data base among watershed characteristics, lake chemistry, and fish status. Individual reports are processed separately for the data bases.

  4. Nanostructured manganese oxides as highly active water oxidation catalysts: a boost from manganese precursor chemistry.

    Science.gov (United States)

    Menezes, Prashanth W; Indra, Arindam; Littlewood, Patrick; Schwarze, Michael; Göbel, Caren; Schomäcker, Reinhard; Driess, Matthias

    2014-08-01

    We present a facile synthesis of bioinspired manganese oxides for chemical and photocatalytic water oxidation, starting from a reliable and versatile manganese(II) oxalate single-source precursor (SSP) accessible through an inverse micellar molecular approach. Strikingly, thermal decomposition of the latter precursor in various environments (air, nitrogen, and vacuum) led to the three different mineral phases of bixbyite (Mn2 O3 ), hausmannite (Mn3 O4 ), and manganosite (MnO). Initial chemical water oxidation experiments using ceric ammonium nitrate (CAN) gave the maximum catalytic activity for Mn2 O3 and MnO whereas Mn3 O4 had a limited activity. The substantial increase in the catalytic activity of MnO in chemical water oxidation was demonstrated by the fact that a phase transformation occurs at the surface from nanocrystalline MnO into an amorphous MnOx (1oxidizing agent. Photocatalytic water oxidation in the presence of [Ru(bpy)3 ](2+) (bpy=2,2'-bipyridine) as a sensitizer and peroxodisulfate as an electron acceptor was carried out for all three manganese oxides including the newly formed amorphous MnOx . Both Mn2 O3 and the amorphous MnOx exhibit tremendous enhancement in oxygen evolution during photocatalysis and are much higher in comparison to so far known bioinspired manganese oxides and calcium-manganese oxides. Also, for the first time, a new approach for the representation of activities of water oxidation catalysts has been proposed by determining the amount of accessible manganese centers. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Radical Chemistry and Structural Relationships of PPCP Degradation by UV/Chlorine Treatment in Simulated Drinking Water.

    Science.gov (United States)

    Guo, Kaiheng; Wu, Zihao; Shang, Chii; Yao, Bo; Hou, Shaodong; Yang, Xin; Song, Weihua; Fang, Jingyun

    2017-09-19

    The UV/chlorine process is an emerging advanced oxidation process (AOP) used for the degradation of micropollutants. However, the radical chemistry of this AOP is largely unknown for the degradation of numerous structurally diverse micropollutants in water matrices of varying quality. These issues were addressed by grouping 34 pharmaceuticals and personal care products (PPCPs) according to the radical chemistry of their degradation in the UV/chlorine process at practical PPCP concentrations (1 μg L -1 ) and in different water matrices. The contributions of HO • and reactive chlorine species (RCS), including Cl • , Cl 2 •- , and ClO • , to the degradation of different PPCPs were compound specific. RCS showed considerable reactivity with olefins and benzene derivatives, such as phenols, anilines, and alkyl-/alkoxybenzenes. A good linear relationship was found between the RCS reactivity and negative values of the Hammett ∑σ p + constant for aromatic PPCPs, indicating that electron-donating groups promote the attack of benzene derivatives by RCS. The contribution of HO • , but not necessarily RCS, to PPCP removal decreased with increasing pH. ClO • showed high reactivity with some PPCPs, such as carbamazepine, caffeine, and gemfibrozil, with second-order rate constants of 9.2 × 10 7 , 1.03 × 10 8 , and 4.16 × 10 8 M -1 s -1 , respectively, which contributed to their degradation. Natural organic matter (NOM) induced significant scavenging of ClO • and greatly decreased the degradation of PPCPs that was attributable to ClO • , with a second-order rate constant of 4.5 × 10 4 (mg L -1 ) -1 s -1 . Alkalinity inhibited the degradation of PPCPs that was primarily attacked by HO • and Cl • but had negligible effects on the degradation of PPCPs by ClO • . This is the first study on the reactivity of RCS, particularly ClO • , with structurally diverse PPCPs under simulated drinking water condition.

  6. Tracing sources of nitrate using water chemistry, land use and nitrogen isotopes in the Ganjiang River, China.

    Science.gov (United States)

    Wang, Peng; Liu, Junzheng; Qi, Shuhua; Wang, Shiqin; Chen, Xiaoling

    2017-10-01

    In this work, we traced sources of nitrate in the Ganjiang River, a major tributary of Yangtze River, China, by analysing the water chemistry, nitrogen isotopes and land use. Water samples from 20 sites in the main stream and tributaries were collected in the dry and wet seasons. The [Formula: see text] ranged from 0.97 to 8.60 ‰, and was significantly higher in the wet season than in the dry season, and significantly higher in tributaries than in the main stream. In the dry season, [Formula: see text] concentrations and [Formula: see text] were significantly negatively correlated with forest and grassland areas, and positively correlated with paddy field and residential area. However, most of the correlations were not significant in the wet season. The results showed that fertilizer was the main source of nitrate in the Ganjiang River, and domestic sewage was important in the dry season, but its contribution was lower than that in other rivers in the Yangtze Basin. In the wet season, the intensified nitrogen cycle caused by high temperature and the mixing effect caused by rainfall made it difficult to trace nitrate sources using [Formula: see text] and land use.

  7. Spatial variation of bacterial community structure of the Northern South China Sea in relation to water chemistry.

    Science.gov (United States)

    Ling, Juan; Dong, Jun-De; Wang, You-Shao; Zhang, Yan-Ying; Deng, Chao; Lin, Li; Wu, Mei-Lin; Sun, Fu-Lin

    2012-08-01

    Spatial distribution, diversity and composition of bacterial communities of the northern South China Sea (SCS) surface water and the relationship with the in situ environmental chemistry were investigated. Polymerase chain reaction denaturing gradient gel electrophoresis (PCR-DGGE) was used to investigate the bacterial community structure. The DGGE gel showed that each sample harbored a distinct bacterial community structure and spatial variations of bacterial community composition among all samples were obviously. A total of 17 intensive bands were excised and the sequence analysis of these DGGE bands revealed that Proteobacteria were the dominant bacterial group of surface water in the north part of SCS. Results of the taxonomic analysis showed that the communities consisted of Proteobacteria (α-subdivision, β-subdivision, γ-subdivision), Actinobacteria, Cyanobacteria, Bacteroidetes and Firmicutes. Unweighted pair group method with arithmetic averages clustering of the sampling stations indicated that all stations were classified mainly based on geographical proximity. Canonical correspondence analysis (CCA) was employed to further investigate the relationships between DGGE band pattern and the environmental variables and the first two CCA ordination axes suggested that the structure of the bacterial community was significantly correlated with the variables of nitrate (F = 1.24, P < 0.05).

  8. Ultrasound-promoted direct functionalization of multi-walled carbon nanotubes in water via Diels-Alder "click chemistry".

    Science.gov (United States)

    Le, Cuong M Q; Cao, Xuan Thang; Lim, Kwon Taek

    2017-11-01

    A facile and environmentally friendly strategy for grafting polymers onto the surface of multi-walled carbon nanotubes (CNTs) was demonstrated by Diels-Alder "click chemistry". Firstly, the copolymers of poly(styrene-alt-maleic anhydride) (PSM) were prepared by the reversible addition-fragmentation chain transfer (RAFT) polymerization and subsequently functionalized with furfuryl amine to introduce anchoring groups. The copolymers were then grafted on CNTs via the Diels-Alder reaction in water through a conventional heating-stirring route and ultrasound-assisted method. The obtained nanocomposite materials were characterized by thermogravimetric analysis, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, Raman spectroscopy and transmission electron microscopy. The results indicated that the reaction rate under ultrasound irradiation was accelerated about 12 times than the one under the conventional heating-stirring condition without losing the grafting efficiency. The direct functionalization of CNTs formed a stably dispersed solution in water, promising a green and effective method for industrial process. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. PREFACE: Water Interfaces in Physics Chemistry and Biology: a multi-disciplinary approach

    Science.gov (United States)

    Bellissent-Funel, Marie-Claire; Dore, John

    2009-07-01

    This 5-day meeting, sponsored by the European Science Foundation (ESF) in partnership with the Fonds zur Förderung der wissenschaftlichen Forschung in Österreich (FWF) was organised by Marie-Claire Bellissent-Funel (Lab. Léon Brillouin (CEA-CNRS), CEA Saclay) and John Dore (School of Physical Sciences, University of Kent). It took place in the Universitatszcentrum (University of Innsbruck), in the ski resort of Obergurgl, Austria, from 8-13 December 2007. The main aim of the meeting was to bring together various groups working on the characteristics of water in a wide range of different conditions, particularly in relation to the difference in behaviour of bulk water and water in close proximity to an interface. Another focus was on the properties of 'solid water' and the free time during the afternoon provided a good opportunity for studying ice interfaces in a different context as the snow conditions were good for ski-ing! An outline of the programme is contained in the PDF file associated with this preface. There was a wide representation encompassing 30 countries and 130 scientists drawn from different science disciplines. Furthermore there was a good range of young scientists, who made an excellent contribution to the poster session. There were, of course, many animated discussions away from the conference room and the feedback forms showed that almost everyone (96%!) felt that they had enjoyed the sessions and had learned something new. There was support for a further conference on this theme in the future. Inevitably, many of the speakers presented information that was in preparation for publication elsewhere and therefore our compilation of some papers in this brief report is not fully representative of the range of topics discussed at the meeting. Further information on specific work reported at the meeting can be obtained by following the author list through the Web of Science or by contacting the authors directly. We report eight short papers from the

  10. Chemistry and isotopic composition of precipitation and surface waters in Khumbu valley (Nepal Himalaya): N dynamics of high elevation basins

    Energy Technology Data Exchange (ETDEWEB)

    Balestrini, Raffaella, E-mail: balestrini@irsa.cnr.it [Water Research Institute, National Research Council (IRSA-CNR), Via del Mulino 19, Brugherio, MB (Italy); Polesello, Stefano [Water Research Institute, National Research Council (IRSA-CNR), Via del Mulino 19, Brugherio, MB (Italy); Sacchi, Elisa [Department of Earth and Environmental Sciences, University of Pavia and IGG-CNR, Via Ferrata 1, 27100 Pavia (Italy)

    2014-07-01

    We monitored the chemical and isotopic compositions of wet depositions, at the Pyramid International Laboratory (5050 m a.s.l.), and surrounding surface waters, in the Khumbu basin, to understand precipitation chemistry and to obtain insights regarding ecosystem responses to atmospheric inputs. The major cations in the precipitation were NH{sub 4}{sup +} and Ca{sup 2+}, whereas the main anion was HCO{sub 3}{sup −}, which constituted approximately 69% of the anions, followed by NO{sub 3}{sup −}, SO{sub 4}{sup 2−} and Cl{sup −}. Data analysis suggested that Na{sup +}, Cl{sup −} and K{sup +} were derived from the long-range transport of marine aerosols. Ca{sup 2+}, Mg{sup 2+} and HCO{sub 3}{sup −} were related to rock and soil dust contributions and the NO{sub 3}{sup −} and SO{sub 4}{sup 2−} concentrations were derived from anthropogenic sources. Furthermore, NH{sub 4}{sup +} was derived from gaseous NH{sub 3} scavenging. The isotopic composition of weekly precipitation ranged from − 1.9 to − 23.2‰ in δ{sup 18}O, and from − 0.8 to − 174‰ in δ{sup 2}H, with depleted values characterizing the central part of the monsoon period. The chemical composition of the stream water was dominated by calcite and/or gypsum dissolution. However, the isotopic composition of the stream water did not fully reflect the composition of the monsoon precipitation, which suggested that other water sources contributed to the stream flow. Precipitation contents for all ions were the lowest ones among those measured in high elevation sites around the world. During the monsoon periods the depositions were not substantially influenced by anthropogenic inputs, while in pre- and post-monsoon seasons the Himalayas could not represent an effective barrier for airborne pollution. In the late monsoon phase, the increase of ionic contents in precipitation could also be due to a change in the moisture source. The calculated atmospheric N load (0.30 kg ha{sup −1} y{sup −1

  11. Toxicity of peracetic acid to fish: Variation among species and impact of water chemistry

    DEFF Research Database (Denmark)

    Straus, David L.; Meinelt, Thomas; Liu, Dibo

    2017-01-01

    of fingerling fish that are important to aquaculture were exposed to PAA for 24 h in static toxicity bioassays in well water. These fish were: fathead minnow, Pimephales promelas; black-nose crappie, Pomoxis nigromaculatus; bluegill, Lepomis macrochirus; blue tilapia, Oreochromis aureus; channel catfish......There has been strong interest in the use of peracetic acid (PAA) in aquaculture as it can be used to disinfect water and hard surfaces and thereby eliminate or lower the burden of fish pathogens. Unfortunately, there has been little research on the toxicity of PAA to fish. Twelve species...... of dissolved organic content had no effect on PAA toxicity. Results of the present study are important information on the safe application of PAA for the aquaculture industry...

  12. Decadal oscillations of the aquatic chemistry of river waters in Latvia

    Science.gov (United States)

    Porshnov, Dmitry; Klavins, Maris

    2016-10-01

    Water quality changes of surface waters can be used to assess human impact intensity, but of importance is to consider also impacts of climate change/variability and naturally occurring changes of environmental quality. In Latvia, during the recent decades a major reduction of anthropogenic pressure has happened due to restructuring of economy and industrial production, resulting in major decrease of loading of many groups of pollutants. However, trends and driving factors for other groups of substances have not been much studied. Long term (1980-2012) results of hydrochemical monitoring, performed in rivers of Latvia, are analysed during this study in connection with long-term sets of hydrological and heliophysical data, using standard statistical approaches. Our results indicate that variation of some hydrochemical values, for example COD and total Fe, show clearly visible decadal oscillated character, while variation of some other values, for example phosphate P and total P, show some individual characteristics of decadal oscillations. These results indicate the presence of a large scale, geochemical and geophysical significant process: multiannual pulse of catchment, driven by variation of solar irradiance through complex interactions between global atmospheric circulation, groundwater and surface waterbodies. The process described in our study is significant from a geochemical point of view and must be taken into account in prediction of water quality and quantity. Impacts of natural processes should be considered in the planning of environmental policy.

  13. Effect of water chemistry on the dissolution rate of the lead corrosion product hydrocerussite.

    Science.gov (United States)

    Noel, James D; Wang, Yin; Giammar, Daniel E

    2014-05-01

    Hydrocerussite (Pb3(CO3)2(OH)2) is widely observed as a corrosion product in drinking water distribution systems. Its equilibrium solubility and dissolution rate can control lead concentrations in drinking water. The dissolution rate of hydrocerussite was investigated as a function of pH, dissolved inorganic carbon (DIC), and orthophosphate concentrations at conditions relevant to drinking water distribution using continuously stirred tank reactors (CSTRs). In the absence of DIC and orthophosphate, the dissolution rate decreased with increasing pH. Addition of DIC inhibited the dissolution of hydrocerussite. The addition of orthophosphate significantly decreased the dissolution rate of hydrocerussite. At conditions with orthophosphate and without DIC, a lead(II) phosphate solid hydroxylpyromorphite (Pb5(PO4)3OH) was observed after reaction, and orthophosphate's inhibitory effect can be attributed to the formation of this low-solubility lead(II) phosphate solid. In the presence of both orthophosphate and DIC, no lead(II) phosphate solid was observed, but the rate was still lowered by the presence of orthophosphate, which might be due to the adsorption of orthophosphate to block reactive sites on the hydrocerussite surface. For systems in which hydroxylpyromorphite was present, the steady-state effluent lead concentrations from the CSTRs were close to the predicted equilibrium solubility of hydroxylpyromorphite. In the absence of orthophosphate rapid equilibration of hydrocerussite was observed. Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. Decadal oscillations of the aquatic chemistry of river waters in Latvia

    Directory of Open Access Journals (Sweden)

    D. Porshnov

    2016-10-01

    Full Text Available Water quality changes of surface waters can be used to assess human impact intensity, but of importance is to consider also impacts of climate change/variability and naturally occurring changes of environmental quality. In Latvia, during the recent decades a major reduction of anthropogenic pressure has happened due to restructuring of economy and industrial production, resulting in major decrease of loading of many groups of pollutants. However, trends and driving factors for other groups of substances have not been much studied. Long term (1980–2012 results of hydrochemical monitoring, performed in rivers of Latvia, are analysed during this study in connection with long-term sets of hydrological and heliophysical data, using standard statistical approaches. Our results indicate that variation of some hydrochemical values, for example COD and total Fe, show clearly visible decadal oscillated character, while variation of some other values, for example phosphate P and total P, show some individual characteristics of decadal oscillations. These results indicate the presence of a large scale, geochemical and geophysical significant process: multiannual pulse of catchment, driven by variation of solar irradiance through complex interactions between global atmospheric circulation, groundwater and surface waterbodies. The process described in our study is significant from a geochemical point of view and must be taken into account in prediction of water quality and quantity. Impacts of natural processes should be considered in the planning of environmental policy.

  15. Effects of water chemistry and surface contact on the toxicity of silver nanoparticles to Bacillus subtilis.

    Science.gov (United States)

    Yi, Jun; Cheng, Jinping

    2017-07-01

    The growing use of silver nanoparticles (AgNPs) has created concerns about its potential impacts on natural microbial communities. In this study, the physicochemical properties of AgNPs and its toxicity on natural bacteria Bacillus subtilis (B. subtilis) were investigated in aqueous conditions. The characterization data showed that AgNPs highly aggregated in aqueous conditions, and the hydrodynamic diameter of AgNPs in aqueous conditions was larger than its primary size. The studied AgNPs was less toxic to B. subtilis in estuarine water as compared to that in Milli-Q water and artificial seawater, which might be due to the observed enhanced aggregation of AgNPs in estuarine water. The toxicity of AgNPs to B. subtilis was greatly reduced when their surface contact was blocked by a dialysis membrane. Scanning electron microscope images showed that exposure contact to AgNPs resulted in damage of the microbial cell wall and enhanced formation of fibrillar structures. These results suggest that particle-cell contact is largely responsible for the observed toxicity of AgNPs in B. subtilis. This study can help to understand the potential impacts of AgNPs to natural microbes, especially in the complex aquatic environments.

  16. Critical loads of acid deposition for wilderness lakes in the sierra nevada (california) estimated by the steady-state water chemistry model

    OpenAIRE

    Shaw, GD; Cisneros, R; Schweizer, D; Sickman, JO; Fenn, ME

    2014-01-01

    Major ion chemistry (2000-2009) from 208 lakes (342 sample dates and 600 samples) in class I and II wilderness areas of the Sierra Nevada was used in the Steady-State Water Chemistry (SSWC) model to estimate critical loads for acid deposition and investigate the current vulnerability of high elevation lakes to acid deposition. The majority of the lakes were dilute (mean specific conductance=8.0 ?S cm?1) and characterized by low acid neutralizing capacity (ANC; mean= 56.8 ?eq L?1). Two variant...

  17. Hydrochemical evaluation of the influences of mining activities on river water chemistry in central northern Mongolia.

    Science.gov (United States)

    Batsaikhan, Bayartungalag; Kwon, Jang-Soon; Kim, Kyoung-Ho; Lee, Young-Joon; Lee, Jeong-Ho; Badarch, Mendbayar; Yun, Seong-Taek

    2017-01-01

    Although metallic mineral resources are most important in the economy of Mongolia, mining activities with improper management may result in the pollution of stream waters, posing a threat to aquatic ecosystems and humans. In this study, aiming to evaluate potential impacts of metallic mining activities on the quality of a transboundary river (Selenge) in central northern Mongolia, we performed hydrochemical investigations of rivers (Tuul, Khangal, Orkhon, Haraa, and Selenge). Hydrochemical analysis of river waters indicates that, while major dissolved ions originate from natural weathering (especially, dissolution of carbonate minerals) within watersheds, they are also influenced by mining activities. The water quality problem arising from very high turbidity is one of the major environmental concerns and is caused by suspended particles (mainly, sediment and soil particles) from diverse erosion processes, including erosion of river banks along the meandering river system, erosion of soils owing to overgrazing by livestock, and erosion by human activities, such as mining and agriculture. In particular, after passing through the Zaamar gold mining area, due to the disturbance of sediments and soils by placer gold mining, the Tuul River water becomes very turbid (up to 742 Nephelometric Turbidity Unit (NTU)). The Zaamar area is also the contamination source of the Tuul and Orkhon rivers by Al, Fe, and Mn, especially during the mining season. The hydrochemistry of the Khangal River is influenced by heavy metal (especially, Mn, Al, Cd, and As)-loaded mine drainage that originates from a huge tailing dam of the Erdenet porphyry Cu-Mo mine, as evidenced by δ34S values of dissolved sulfate (0.2 to 3.8 ‰). These two contaminated rivers (Tuul and Khangal) merge into the Orkhon River that flows to the Selenge River near the boundary between Mongolia and Russia and then eventually flows into Lake Baikal. Because water quality problems due to mining can be critical, mining

  18. Stable isotope, cation chemistry and petrographic evidence of multiple water sources influencing the alteration of Antarctic hyaloclastites

    Science.gov (United States)

    Antibus, J. V.; Panter, K. S.; Wilch, T. I.; Dunbar, N. W.; McIntosh, W. C.

    2010-12-01

    Minna Bluff is a 45 km-long, up to 1100 meter-high volcanic peninsula in the southern Ross Sea, Antarctica. Sequences of lava flows and domes, volcanic sediments, and hyaloclastite breccia interbedded with evidence of glaciation expose a complex record of development from 11.8 to 6.2 Ma [1]. Hyaloclastites are being used to help unravel paleoenvironmental conditions at Minna Bluff. Hyaloclastites are glass-rich sediments formed by the quenching and granuation of magma in contact with water that readily hydrates and alters. Minna Bluff hyaloclastite deposits have alteration assemblages consisting of carbonates and zeolites in veins,vugs, vesicles, and infilling interclast voids. Carbonates consist of low- and high-Mg calcite, dolomite, and magnesite. Zeolites include phillipsite and chabazite. Carbonate textures include blocky, isopachus, bladed (aragonite),radial fibrous spar and microcrystalline micrite. Complex zoning/interlayering of carbonates and zeolites suggest changing physiochemical conditions and/or multiple generations of fluids. Zeolite cation (Na+K)/Ca ratios show a broad range from 1) and phillipsite (>4) [2], and high Mg, Sr/Ca ratios in carbonates with δ18Owater around 0‰. Meteroric water is characterized by low zeolite Na+K/Ca ratios, low carbonate Mg, Sr/Ca ratios,and light δ18Owater values approaching -35‰. Hydrothermal fluids may show characteristics of both. Water that has interacted with volcanic rock in hydrothermal systems would have higher cation ratios and heavier δ18O values than fresh meteroric water. This study of hyaloclastite alteration mineral chemistry and textures illustrates the complexity of the hydrogeologic system involved in the formation of Minna Bluff. A valuable addition to the understanding of the paleoenvironment at Minna Bluff would be a model of the extent to which the individual water sources circulated within the volcanic sequence of hyaloclastites as well as determining patterns of water source mixing. [1

  19. Photocatalytic Oxidation and Reduction Chemistry and a New Process for Treatment of Pink Water and Related Contaminated Water

    Science.gov (United States)

    1996-10-01

    passed to the near UV region. Actinometry measurements showed that about 5.2 watts of incident light that is available for TiO2 photocatalysis (300-400...studies. The combined processes of TiO2 assisted photocatalysis and follow-on biological mineralization have the potential for being an effective...Na2EDTA-2H2 0 were all mixed and stirred thoroughly. The reactor system was assembled and checked for any leaks by running water through it. TiO2 was added

  20. Influence of operating and water-chemistry parameters on fuel cladding corrosion and deposition of corrosion products on cladding surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Kritsky, V.G.; Berezina, I.G.; Rodionov, Y.A., E-mail: kritsky@givnipiet.spb.ru, E-mail: alemaskina@givnipiet.ru [Leading Inst. ' VNIPIET' , Saint Petersburg (Russian Federation)

    2010-07-01

    A description of mass transfer mechanism of corrosion products in the primary coolant circuit is a complicated problem. The deposits of crud is to be proportional to the amount of corrosion products circulating in the primary coolant circuit, therefore all models of mass transfer in the circuit include the change of corrosion products concentration and the corrosion rate in time, removing these products by filters and deposition. Decontamination of the circuit equipment and replacement work needs lead to a local change of corrosion rate which results in the increase of corrosion products concentration in the circuit and the increase of deposits on surfaces. If due to incorrect water chemistry conditions for corrosion products deposition in the core are created not only the activity of the coolant increases but the hydraulic resistance of the reactor also grows which results in the increase of the pressure drop at the reactor. The phenomenon of 'pressure drop' which takes place in NPP with VVER reactors was considered. The reasons of this phenomenon are the following: the great removal of corrosion products (CP) from steam generator surfaces after decontamination, change of CP behavior and then consequent deposit of CP on the fuel element surfaces; and, sub-cooled boiling takes place on the some of fuel element and results in the acceleration of corrosion products deposit, the increase of nuclide activation period and coolant radioactivity. A model was developed to explain pressure drop rise in-core and deposits redistribution in the core and in the primary circuit of NPP with VVER-440. The physical-chemical basis of the model is the transport corrosion products dependence on temperature, pH{sub T} value of coolant, and correlation between rates of corrosion products (Fe) formation (after steam generators decontamination) and their removing from the circuit. The aim of our modeling is to predict the growth of pressure difference on the basis of regular

  1. U3Si2 behavior in H2O environments: Part II, pressurized water with controlled redox chemistry

    Science.gov (United States)

    Nelson, A. T.; Migdisov, A.; Wood, E. Sooby; Grote, C. J.

    2018-03-01

    Recent interest in U3Si2 as an advanced light water reactor fuel has driven assessment of numerous properties, but characterization of its response to H2O environments is sparse in available literature. The behavior of U3Si2 in H2O containing atmospheres is investigated and presented in a two-part series of articles. This work examines the behavior of U3Si2 following exposure to pressurized H2O at temperatures from 300 to 350 °C. Testing was performed using two autoclave configurations and multiple redox conditions. Use of solid state buffers to attain a controlled water chemistry is also presented as a means to test actinide-bearing systems. Buffers were used to vary the hydrogen concentration between 1 and 30 parts per million H2. Testing included UN, U3Si5, and UO2. Both UN and U3Si5 were found to rapidly pulverize in less than 50 h at 300 °C. Uranium dioxide was included as a control for the autoclave system, and was found to be minimally impacted by exposure to pressurized water at the conditions tested for extended time periods. Testing of U3Si2 at 300 °C found reasonable stability through 30 days in 1-5 ppm H2. However, pulverization was observed following 35 days. The redox condition of testing strongly affected pulverization. Characterization of the resulting microstructures suggests that the mechanism responsible for pulverization under more strongly reducing conditions differs from that previously identified. Hydride formation is hypothesized to drive this transition. Testing performed at 350 °C resulted in rapid pulverization of U3Si2 in under 50 h.

  2. Interaction of forsterite-91 with distilled water and artificial seawater: a prebiotic chemistry experiment

    Science.gov (United States)

    de Souza, Cláudio M. D.; Carneiro, Cristine E. A.; Baú, João Paulo T.; da Costa, Antonio C. S.; Ivashita, Flávio F.; Paesano, Andrea; di Mauro, Eduardo; de Santana, Henrique; Holm, Nils G.; Neubeck, Anna; Zaia, Cássia T. B. V.; Zaia, Dimas A. M.

    2013-04-01

    In the present work, the interactions between forsterite-91 with distilled water and forsterite-91 with artificial seawater were studied at two pHs (2.0 and 8.0) using different techniques. A large increase in pH was observed for samples incubated at an initially acidic pH (2.0) due to the dissolution of forsterite-91 in distilled water and artificial seawater. Thus, in acidic hydrothermal vents, an increase in the amount of hydrocarbons and magnetite should be expected due to the release of Fe(II). The pHPZC decreased and the pHIEP increased when forsterite-91 was treated with distilled water and artificial seawater. The ions from the artificial seawater had an effect on zeta potential. Scanning electron microscopy (SEM) images and X-ray diffractograms showed halite in the samples of forsterite-91 mixed with artificial seawater. The presence of halite or adsorption of ions on the surface of forsterite-91 could affect the synthesis of magnetite and hydrocarbons in hydrothermal vents, due to a decrease in the dissolution rates of forsterite-91. The dissolution of forsterite-91 yields low concentrations of Fe(III) and Mn(II) as detected by electron paramagnetic resonance (EPR) spectroscopy. Microanalysis of forsterite-91 showed a higher amount of Mn, with an oxidation that was likely not +II, as Mn in supernatant solutions was only detected by EPR spectroscopy after mixing with artificial seawater at pH 2.0. As Fe(III) and Mn(II) are catalyst constituents of magnetite and manganese oxide, respectively, their presence is important for synthesis in hydrothermal vents. Etch pits were observed only in the forsterite-91 sample mixed with distilled water at pH 8.0. Na, Cl, S, Ca and K were detected in the samples mixed with artificial seawater by SEM-EDS. Si, Mg, Fe and Al were detected in almost all supernatant samples due to forsterite-91 dissolution. Cr was not dissolved in the experiments, thus Cr in the mineral could serve as an effective catalyst for Fischer Tropsch

  3. Chemistry of natural waters and its relation to Buruli ulcer in Ghana

    Directory of Open Access Journals (Sweden)

    Julianne Hagarty

    2015-03-01

    New hydrological insights: Trace metals, thought to aid in the preferential growth of M. ulcerans, are present in higher concentrations in mining pits and stagnant pools than in other tested water bodies. Arsenic in particular could serve as a double threat for BU incidence: it could support the growth of M. ulcerans while suppressing immune systems, making the population more susceptible to disease. Few other differences between endemic and non-endemic communities exist, implying other variables such as human behavior may also control the onset of Buruli ulcer.

  4. Bad chemistry

    OpenAIRE

    Petsko, Gregory A

    2004-01-01

    General chemistry courses haven't changed significantly in forty years. Because most basic chemistry students are premedical students, medical schools have enormous influence and could help us start all over again to create undergraduate chemistry education that works.

  5. Do distinct water chemistry, reservoir age and disturbance make any difference on phosphatase activity?

    Directory of Open Access Journals (Sweden)

    Maria-José BOAVIDA

    2003-08-01

    Full Text Available Alkaline phosphatase activity was assessed concomitantly with total phosphorus, orthophosphate and phosphomonoester concentrations in two meso-eutrophic reservoirs with distinct age and subjected to different kinds of environmental influence. Differences in conductivity, temperature and pH were found. However, during the study period alkaline phosphatase activity was similar in both reservoirs. Water colour was higher in S. Serrada Reservoir. This fact can be related to (1 reservoir age (2 high internal disturbance (3 large imputs of allochthonous detritus, resulting from the combined effect of grazing, fire and catchment slope. Despite the high water colour recorded in S. Serrada, alkaline phosphatase activity was apparently not inactivated by humic substances. Besides, the obtained results demonstrated that hydrolysis of phosphomonoesters by alkaline phosphatase was not important for orthophosphate regeneration in these reservoirs. Probably orthophosphate was always available to biota. In fact, in the experiments based on Selenastrum capricornutum Printz algal test, similar phytoplankton growth responses were obtained for different phosphorus concentrations. Thus, these results seem to indicate that phosphorus was not a limiting nutrient in either reservoir. Although phosphatase activity was significantly correlated with some phytoplankton genera in both reservoirs, no significant correlations were found between enzyme activity and chlorophyll-a. Significant correlations between phosphatase activity and crustacean zooplankton were only recorded in S. Serrada. In spite of these results there was some indication that the main source of phosphatase might have been bacteria involved in decomposition processes instead of phyto- and zooplankton taxa

  6. Impact of forest soil tillage on the chemistry of tension lysimeter soil water. [Finland

    Energy Technology Data Exchange (ETDEWEB)

    Starr, M.

    1987-01-01

    Sources of variation in pH, conductivity, and soluble nutrient concentrations of surface soil water taken with tension cup lysimeters from a tillage experiment in southwestern Finland are examined. Samples were taken weekly during the growing season (June-September) for 3 years (1982-84) from three treatments: untilled, clear-felled control; rotating disc ploughing, and tilt ploughing. Lysimeters were installed at 25-30 cm depth (along the centre of the plough ridge in the case of the plough treatments). Clear-felling and tillage had been carried out in 1979 and artificial reforestation in 1980. Compared to control values, ploughing resulted in higher conductivity and Ca/sup 2+/ concentrations but lower pH and NO/sub 3//sup -/ concentrations. The effect on total N, NH/sub 4//sup +/ and K/sup +/ concentration was irregular and there was no effect on total P and PO/sub 4//sup 3./ An analysis of variance model indicated that treatment variation was considerably smaller than seasonal variation, which was significant for all properties. There was also significant weekly variation for all properties except Ca/sup 2+/ concentrations. Solute concentrations generally decreased during the season. The results are discussed in terms of: leaching and mineralisation of nutrients in the logging residue (high C/N ratio) incorporated by ploughing, location of lysimeter cup, source and fraction of soil water being sampled, nutrient fixation and uptake, and weather factors. 1 fig., 3 tabs., 17 refs.

  7. A mini review on the chemistry and catalysis of the water gas shift reaction

    CERN Document Server

    Zhao, Zhun

    2014-01-01

    Water gas shift (WGS) reaction is a chemical reaction in which carbon monoxide reacts with water vapor to form carbon dioxide and hydrogen. It is an important reaction industrially used in conjunction with steam reforming of hydrocarbons for the production of high purity hydrogen. Grenoble et al examined the roles of both active metals and metal oxide support on the kinetics of the WGS reaction. They found out that the turn over numbers of various Al2O3 supported transition metals decreased in the trend of Cu, Re, Co, Ru, Ni, Pt, Os, Au, Fe, Pd, Rh, and Ir, which corresponds nicely to the observed volcano shaped correlation between catalytic activities and respective CO adsorption heat. This is a strong indication that CO gets activated on the metal surface during the reaction and different metals have different activation energies. The authors also observed that the turn over number of Pt/Al2O3 was one order of magnitude higher than that of Pt/SiO2, indicating a strong support effect, which the authors ascri...

  8. Singlet oxygen chemistry in water. 2. Photoexcited sensitizer quenching by O2 at the water-porous glass interface.

    Science.gov (United States)

    Giaimuccio, Jovan; Zamadar, Matibur; Aebisher, David; Meyer, Gerald J; Greer, Alexander

    2008-12-11

    Insight into the O2 quenching mechanism of a photosensitizer (static or dynamic) would be useful for the design of heterogeneous systems to control the mode of generation of 1O2 in water. Here, we describe the use of a photosensitizer, meso-tetra(N-methyl-4-pyridyl)porphine (1), which was adsorbed onto porous Vycor glass (PVG). A maximum loading of 1.1 x 10(-6) mol 1 per g PVG was achieved. Less than 1% of the PVG surface was covered with photosensitizer 1, and the penetration of 1 reaches a depth of 0.32 mm along all faces of the glass. Time-resolved measurements showed that the lifetime of triplet 1*-ads was 57 microseconds in water. Triplet O2 quenched the transient absorption of triplet 1*-ads; for samples containing 0.9 x 10(-6)-0.9 x 10(-8) mol 1 adsorbed per g PVG, the Stern-Volmer constant, K(D), ranged from 23,700 to 32,100 M(-1). The adduct formation constant, Ks, ranged from 1310 to 510 M(-1). The amplitude of the absorption at 470 nm decreased slightly (by about 0.1) with increased O2 concentrations. Thus, the quenching behavior of triplet 1*-ads by O2 was proposed to be strongly dependent on dynamic quenching. Only approximately 10% of the quenching was attributed to the static quenching mechanism. The quenching of triplet 1*-ads was similar to that observed for photosensitizers in homogeneous solution which are often quenched dynamically by O2.

  9. A STUDY ON LEGIONELLA PNEUMOPHILA, WATER CHEMISTRY, AND ATMOSPHERIC CONDITIONS IN COOLING TOWERS AT THE SAVANNAH RIVER SITE

    Energy Technology Data Exchange (ETDEWEB)

    Smith, C.; Brigmon, R.

    2009-10-20

    elevated Legionella concentrations when the dew point temperature was high--a summertime occurrence. However, analysis of the three years of Legionella monitoring data of the 14 different SRS Cooling Towers demonstrated that elevated concentrations are observed at all temperatures and seasons. The objective of this study is to evaluate the ecology of L. pneumophila including serogroups and population densities, chemical, and atmospheric data, on cooling towers at SRS to determine whether relationships exist among water chemistry, and atmospheric conditions. The goal is to more fully understand the conditions which inhibit or encourage L. pneumophila growth and supply this data and associated recommendations to SRS Cooling Tower personnel for improved management of operation. Hopefully this information could then be used to help control L. pneumophila growth more effectively in SRS cooling tower water.

  10. Pore water chemistry of an alkaline rift valley lake: Lake Turkana, Kenya

    Energy Technology Data Exchange (ETDEWEB)

    Cerling, T.E.; Johnson, T.C.; Halfman, J.D.; Lister, G.

    1985-01-01

    Lake Turkana is the largest closed basin lake in the African rift system. It has evolved through the past 5000 years to become a moderately alkaline lake. Previous mass balance argument suggest that sulfate is removed from the lake by sulfate reduction in the sediments, and that the lake is accumulating in chloride, sodium, and alkalinity. Studies of pore water from 12 meter cores collected in November 1984 show that sulfate is reduced in the sediment column with a net production of alkalinity. Some sodium is lost from the lake and diffuses into the sediment to maintain charge balance. At several meters depth, organic matter is destroyed by methanogenic bacteria, as shown by the high delta /sup 13/C values for dissolved inorganic carbon. Magnesium and calcium molar ratios change with depth; chloride, sodium, and alkalinity also change with depth.

  11. Participation in the 2001 IAEA interlaboratory comparison on geothermal water chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Joe, Kih Soo; Choi, Kwang Soon; Han, Sun Ho; Suh, Moo Yul; Jeon, Young Shin; Choi, Ke Chun; Pyo, Hyung Yul; Kim, Yong Bok; Kim, Jong Gu; Kim, Won Ho [Korea Atomic Energy Research Institute, Taejeon (Korea)

    2002-04-01

    Korea Atomic Energy Research Institute Analytical laboratory participated in the 2001 IAEA Interlaboratory Comparison on chemical analysis of Geothermal Water containing high salinity organized by IAEA Hydrology Laboratory(INT/0/060). 14 items such as pH, electroconductivity, HCO{sub 3}, Cl, F, SO{sub 4}, SiO{sub 2}, B, Li, Na, K, Ca, Mg were analyzed. The result of this program showed that Korea Atomic Energy Research Institute laboratory was ranked within 15% range from top level. Major analytical methods were applied for this activity such as ICP-AES, AAS, IC, pH meter, conductometer and acid titration. 8 refs., 48 figs., 9 tabs. (Author)

  12. Oxidation Chemistry and Kinetics of Model Compounds in Supercritical Water: Glucose, Acetic Acid, and Methylene Chloride

    Science.gov (United States)

    1993-06-01

    daughter, Jerin. I’m coming home. U I I I UDe~afon vii I II I I I - Trust in the Lord with all thine heart; and lean not unto thine own understanding...Introduction Supercritical water oxidation (SCWO) is a resourceful method that can be used to destroy 3 harmful wastes without producing unsafe...mol/cm3 X I0Ś mo/ cnmi mfona % ex Closure 247A 550±1 1.00±.03 2.03±.07 8.0±0.4 98.0±0.3 .0.71 99.1 248 475±1 1.06±.03 2.13±.08 7.9±0.4 14.1±3.6

  13. Spatio-temporal variation in stream water chemistry in a tropical urban watershed

    Directory of Open Access Journals (Sweden)

    Alonso Ramírez

    2014-06-01

    Full Text Available Urban activities and related infrastructure alter the natural patterns of stream physical and chemical conditions. According to the Urban Stream Syndrome, streams draining urban landscapes are characterized by high concentrations of nutrients and ions, and might have elevated water temperatures and variable oxygen concentrations. Here, we report temporal and spatial variability in stream physicochemistry in a highly urbanized watershed in Puerto Rico. The main objective of the study was to describe stream physicochemical characteristics and relate them to urban intensity, e.g., percent impervious surface cover, and watershed infrastructure, e.g., road and pipe densities. The Río Piedras Watershed in the San Juan Metropolitan Area, Puerto Rico, is one of the most urbanized regions on the island. The Río Piedras presented high solute concentrations that were related to watershed factors, such as percent impervious cover. Temporal variability in ion concentrations lacked seasonality, as did all other parameters measured except water temperature, which was lower during winter and highest during summer, as expected based on latitude. Spatially, stream physicochemistry was strongly related to watershed percent impervious cover and also to the density of urban infrastructure, e.g., roads, pipe, and building densities. Although the watershed is serviced by a sewage collection system, illegal discharges and leaky infrastructure are probably responsible for the elevated ion concentration found. Overall, the Río Piedras is an example of the response of a tropical urban watershed after major sewage inputs are removed, thus highlighting the importance of proper infrastructure maintenance and management of runoff to control ion concentrations in tropical streams.

  14. Unmixing stream water chemistry: nutrient load pathways assessed from high resolution data

    Science.gov (United States)

    Mellander, P.-E.; Melland, A. R.; Jordan, P.; Murphy, P. N. C.; Wall, D.; Shortle, G.

    2012-04-01

    In order to mitigate anthropogenic nutrient transfers to surface waters there is a need to identify and quantify the transfer pathways and their influence on delivery to streams. The Agricultural Catchments Programme (ACP) aims to provide scientific evidence needed to support Irish agriculture in meeting the requirements of the Water Framework Directive (WFD). In this paper we combine yearly averaged and site specific pathway analysis (End Member Mixing Analysis, EMMA) with high temporal resolution catchment-integrated monitoring data to characterise nitrogen (N) and phosphorus (P) transfer pathways in six Irish agricultural river catchments with different land management, soil drainage and geology. A Loadograph Recession Analysis (LRA) method is introduced, to unmix end-of-catchment stream nutrient loads into specific delivery pathways (overland flow, near-surface interflow and a range of deep subsurface pathways) and quantify their contributions of total oxidised nitrogen (TON), total reactive phosphorus (TRP) and total phosphorus (TP). The method uses high temporal resolution N and P load data at river outlets coupled with time-averaged data of N and P concentrations from multilevel monitoring wells. Nitrogen and P pathways in the catchments are characterised and possible implications for mitigation strategies and policies are explored. Results suggest that, in catchments with permeable soils and geology, subsurface pathways will need to be considered for mitigation strategies for both diffuse N and P delivery and measures that target surface transfer pathways such as riparian buffer strips may be ineffective. In such catchments, long chemical recessions from storm events may prolong impacts on the ecological status of receiving rivers. While EMMA gave an idea of the proportions of N and P transfer pathways during baseflow conditions over a year, and has potential to improve understanding of upland conditions, the LRA has the added benefit of being able to

  15. Atmospheric Deposition and Surface-Water Chemistry in Mount Rainier and North Cascades National Parks, U.S.A., Water Years 2000 and 2005-2006

    Science.gov (United States)

    Clow, David W.; Campbell, Donald H.

    2008-01-01

    High-elevation aquatic ecosystems in Mount Rainier and North Cascades National Parks are highly sensitive to atmospheric deposition of nitrogen and sulfur. Thin, rocky soils promote fast hydrologic flushing rates during snowmelt and rain events, limiting the ability of basins to neutralize acidity and assimilate nitrogen deposited from the atmosphere. Potential effects of nitrogen and sulfur deposition include episodic or chronic acidification of terrestrial and aquatic ecosystems. In addition, nitrogen deposition can cause eutrophication of water bodies and changes in species composition in lakes and streams. This report documents results of a study performed by the U.S. Geological Survey, in cooperation with the National Park Service, of the effects of atmospheric deposition of nitrogen and sulfur on surface-water chemistry in Mount Rainier and North Cascades National Parks. Inorganic nitrogen in wet deposition was highest in the vicinity of North Cascades National Park, perhaps due to emissions from human sources and activities in the Puget Sound area. Sulfur in wet deposition was highest near the Pacific coast, reflecting the influence of marine aerosols. Dry deposition generally accounted for less than 30 percent of wet plus dry inorganic nitrogen and sulfur deposition, but occult deposition (primarily fog) represents a potentially substantial unmeasured component of total deposition. Trend analyses indicate inorganic nitrogen in wet deposition was relatively stable during 1986-2005, but sulfur in wet deposition declined substantially during that time, particularly after 2001, when emissions controls were added to a large powerplant in western Washington. Surface-water sulfate concentrations at the study site nearest the powerplant showed a statistically significant decrease between 2000 and 2005-06, but there was no statistically significant change in alkalinity, indicating a delayed response in surface-water alkalinity. Seasonal patterns in surface-water

  16. Remote sensing as a tool for monitoring water quality parameters for Mediterranean Lakes of European Union water framework directive (WFD) and as a system of surveillance of cyanobacterial harmful algae blooms (SCyanoHABs).

    Science.gov (United States)

    Gómez, José Antonio Domínguez; Alonso, Covadonga Alonso; García, Ana Alonso

    2011-10-01

    Remote sensing has been used from the 1980s to study inland water quality. However, it was not until the beginning of the twenty-first century that CHRIS (an experimental multi-angle sensor with good spectral and spatial resolutions) and MERIS (with good temporal and spectral resolutions) started to acquire imagery with very good resolutions, which allowed to develop a reliable imagery acquisition system so as to consider remote sensing as an inland water management tool. This paper presents the methodology developed, from the field data acquisition with which to build a freshwater spectral library and the study of different atmospheric correction systems for CHRIS mode 2 and MERIS images, to the development of algorithms to determine chlorophyll-a and phycocyanin concentrations and bloom sites. All these algorithms allow determining water eutrophic and ecological states, apart from generating surveillance maps of toxic cyanobacteria with the main objective of Assessment of the Water Quality as it was used for Monitoring Ecological Water Quality in smallest Mediterranean Reservoirs integrated in the Intercalibration Exercise of European Union Water Framework Directive (WFD). We keep on using it to monitor the Ecological Quality Ratio (EQR) in Spain inland water.

  17. Progression towards optimization of viscosity of highly concentrated carbonaceous solid-water slurries by incorporating and modifying surface chemistry parameters with and without additives

    Science.gov (United States)

    Mukherjee, Amrita

    Carbonaceous solid-water slurries (CSWS) are concentrated suspensions of coal, petcoke bitumen, pitch etc. in water which are used as feedstock for gasifiers. The high solid loading (60-75 wt.%) in the slurry increases CSWS viscosity. For easier handling and pumping of these highly loaded mixtures, low viscosities are desirable. Depending on the nature of the carbonaceous solid, solids loading in the slurry and the particle size distribution, viscosity of a slurry can vary significantly. Ability to accurately predict the viscosity of a slurry will provide a better control over the design of slurry transport system and for viscosity optimization. The existing viscosity prediction models were originally developed for hard-sphere suspensions and therefore do not take into account surface chemistry. As a result, the viscosity predictions using these models for CSWS are not very accurate. Additives are commonly added to decrease viscosity of the CSWS by altering the surface chemistry. Since additives are specific to CSWS, selection of appropriate additives is crucial. The goal of this research was to aid in optimization of CSWS viscosity through improved prediction and selection of appropriate additive. To incorporate effect of surface chemistry in the models predicting suspension viscosity, the effect of the different interfacial interactions caused by different surface chemistries has to be accounted for. Slurries of five carbonaceous solids with varying O/C ratio (to represent different surface chemistry parameters) were used for the study. To determine the interparticle interactions of the carbonaceous solids in water, interfacial energies were calculated on the basis of surface chemistries, characterized by contact angles and zeta potential measurements. The carbonaceous solid particles in the slurries were assumed to be spherical. Polar interaction energy (hydrophobic/hydrophilic interaction energy), which was observed to be 5-6 orders of magnitude higher than the

  18. Exposure to and colonisation by antibiotic-resistant E. coli in UK coastal water users: Environmental surveillance, exposure assessment, and epidemiological study (Beach Bum Survey).

    Science.gov (United States)

    Leonard, Anne F C; Zhang, Lihong; Balfour, Andrew J; Garside, Ruth; Hawkey, Peter M; Murray, Aimee K; Ukoumunne, Obioha C; Gaze, William H

    2018-01-15

    Antibiotic-resistant bacteria (ARB) present a global public health problem. With numbers of community-acquired resistant infections increasing, understanding the mechanisms by which people are exposed to and colonised by ARB can help inform effective strategies to prevent their spread. The role natural environments play in this is poorly understood. This is the first study to combine surveillance of ARB in bathing waters, human exposure estimates and association between exposure and colonisation by ARB in water users. 97 bathing water samples from England and Wales were analysed for the proportion of E. coli harbouring bla CTX-M . These data were used to estimate the likelihood of water users ingesting bla CTX-M -bearing E. coli. Having identified surfers as being at risk of exposure to ARB, a cross-sectional study was conducted. Regular surfers and non-surfers were recruited to assess whether there is an association between surfing and gut colonisation by bla CTX-M- bearing E. coli. 11 of 97 bathing waters sampled were found to contain bla CTX-M -bearing E. coli. While the percentage of bla CTX-M -bearing E. coli in bathing waters was low (0.07%), water users are at risk of ingesting these ARB. It is estimated that over 25 million water sports sessions occurred in 2015 resulting in the ingestion of at least one bla CTX-M -bearing E. coli. In the epidemiological survey, 9/143 (6.3%) surfers were colonised by bla CTX-M -bearing E. coli, as compared to 2/130 (1.5%) of non-surfers (risk ratio=4.09, 95% CI 1.02 to 16.4, p=0.046). Surfers are at risk of exposure to and colonisation by clinically important antibiotic-resistant E. coli in coastal waters. Further research must be done on the role natural environments play in the transmission of ARB. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  19. Integrated Ecological River Health Assessments, Based on Water Chemistry, Physical Habitat Quality and Biological Integrity

    Directory of Open Access Journals (Sweden)

    Ji Yoon Kim

    2015-11-01

    Full Text Available This study evaluated integrative river ecosystem health using stressor-based models of physical habitat health, chemical water health, and biological health of fish and identified multiple-stressor indicators influencing the ecosystem health. Integrated health responses (IHRs, based on star-plot approach, were calculated from qualitative habitat evaluation index (QHEI, nutrient pollution index (NPI, and index of biological integrity (IBI in four different longitudinal regions (Groups I–IV. For the calculations of IHRs values, multi-metric QHEI, NPI, and IBI models were developed and their criteria for the diagnosis of the health were determined. The longitudinal patterns of the river were analyzed by a self-organizing map (SOM model and the key major stressors in the river were identified by principal component analysis (PCA. Our model scores of integrated health responses (IHRs suggested that mid-stream and downstream regions were impaired, and the key stressors were closely associated with nutrient enrichment (N and P and organic matter pollutions from domestic wastewater disposal plants and urban sewage. This modeling approach of IHRs may be used as an effective tool for evaluations of integrative ecological river health..

  20. Water chemistry and electrical conductivity database for rivers in Yellowstone National Park, Wyoming

    Science.gov (United States)

    Clor, Laura E.; McCleskey, R. Blaine; Huebner, Mark A.; Lowenstern, Jacob B.; Heasler, Henry P.; Mahony, Dan L.; Maloney, Tim; Evans, William C.

    2012-01-01

    Chloride flux has been used to estimate heat flow in volcanic environments since the method was developed in New Zealand by Ellis and Wilson (1955). The method can be applied effectively at Yellowstone, because nearly all of the water discharged from its thermal features enters one of four major rivers (the Madison, Yellowstone, Snake, and Falls Rivers) that drain the park, and thus integration of chloride fluxes from all these rivers provides a means to monitor the total heat flow from the entire Yellowstone volcanic system (Fournier and others, 1976; Fournier, 1979). Fournier (1989) summarized the results and longterm heat-flow trends from Yellowstone, and later efforts that applied the chloride inventory method to estimate heat flow were described by Ingebritsen and others (2001) and Friedman and Norton (2007). Most recently, the U.S. Geological Survey (USGS), in conjunction with the National Park Service, has provided publicly accessible reports on solute flux, based on periodic sampling at selected locations (Hurwitz and others, 2007a,b). While these studies have provided a wealth of valuable data, winter travel restrictions and the great distances between sites present significant logistical challenges and have limited collection to a maximum of 28 samples per site annually.

  1. Corrosion product balances for the Ringhals PWR plants based on extensive fuel crud and water chemistry measurements

    Energy Technology Data Exchange (ETDEWEB)

    Lundgren, K.; Wikmark, G., E-mail: klas@alara.se, E-mail: gunnar@alara.se [ALARA Engineering AB, Stensborgsgatan 4, Vasteras (Sweden); Bengtsson, B., E-mail: bernt.bengtsson@vattenfall.com [Ringhals AB., Varobacka (Sweden)

    2010-07-01

    The corrosion product balance in a PWR plant is of great importance for the fuel performance as well as for the radiation field buildup. This balance is of special concern in connection to steam generator replacement (SGR) and power uprate projects. The Ringhals PWRs are all of Westinghouse design. Two of the plants have performed Steam Generator Replacement (SGR) to I-690 SG tubes and such a replacement is being planned in the third and last unit in 2011. Two of the units are in different phases of power uprate projects. The plants are all on 10-14-months cycles operating with medium to high fuel duty. Water chemistry is controlled by a pH300 in the range ∼7.2 to 7.4 from beginning of cycle to end of cycle (BOC-EOC) in the units with new SGs while kept at a coordinated pH of 7.2 in the one still using I-600. The maximum Li content has recently been increased to about 4.5 to 5 ppm in all units. In order to be able to improve the assessment of corrosion product balances in the plants, comprehensive fuel crud measurements were performed in 2007. Improved integrated reactor water sampling techniques have also been introduced in order to make accurate mass balances possible. The corrosion products covered in the study are the main constituents, Ni, Fe and Cr in the primary circuit Inconel and stainless steel, together with Co. The activated corrosion products, Co-58, Co-60, Cr-51, Fe-59 and Mn-54, are all mainly produced through neutron irradiation of the covered corrosion products. The main results of the corrosion product balances are presented. Observed differences between the plants, indicating significant impact of pH control and SG tube materials, are presented and discussed. The importance of accurate sampling techniques is especially addressed in this paper. (author)

  2. Removal of triazine-based pollutants from water by carbon nanotubes: Impact of dissolved organic matter (DOM) and solution chemistry.

    Science.gov (United States)

    Engel, Maya; Chefetz, Benny

    2016-12-01

    Adsorption of organic pollutants by carbon nanotubes (CNTs) in the environment or removal of pollutants during water purification require deep understanding of the impacts of the presence of dissolved organic matter (DOM). DOM is an integral part of environmental systems and plays a key role affecting the behavior of organic pollutants. In this study, the effects of solution chemistry (pH and ionic strength) and the presence of DOM on the removal of atrazine and lamotrigine by single-walled CNTs (SWCNTs) was investigated. The solubility of atrazine slightly decreased (∼5%) in the presence of DOM, whereas that of lamotrigine was significantly enhanced (by up to ∼70%). Simultaneous introduction of DOM and pollutant resulted in suppression of removal of both atrazine and lamotrigine, which was attributed to DOM-pollutant competition or blockage of adsorption sites by DOM. However the decrease in removal of lamotrigine was also a result of its complexation with DOM. Pre-introduction of DOM significantly reduced pollutant adsorption by the SWCNTs, whereas introduction of DOM after the pollutant resulted in the release of adsorbed atrazine and lamotrigine from the SWCNTs. These data imply that DOM exhibits higher affinity for the adsorption sites than the triazine-based pollutants. In the absence of DOM atrazine was a more effective competitor than lamotrigine for adsorption sites in SWCNTs. However, competition between pollutants in the presence of DOM revealed lamotrigine as the better competitor. Our findings help unravel the complex DOM-organic pollutant-CNT system and will aid in CNT-implementation in water-purification technologies. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Indicators: Soil Chemistry

    Science.gov (United States)

    The chemical makeup of the soil can provide information on wetland condition, wetland water quality and services being provided by the wetland ecosystem. Analyzing soil chemistry reveals if the soil is contaminated with a toxic chemical or heavy metal.

  4. Aspects of the physics and chemistry of water radiolysis by fast neutrons and fast electrons in nuclear reactors

    Energy Technology Data Exchange (ETDEWEB)

    McCracken, D.R. [Atomic Energy of Canada Limited, Chalk River, Ontario (Canada); Tsang, K.T. [Atomic Energy of Canada Limited, Mississauga, Ontario (Canada); Laughton, P.J

    1998-09-01

    Detailed radiation physics calculations of energy deposition have been done for the coolant of CANDU reactors and Pressurized Water Reactors (PWRs). The geometry of the CANDU fuel channel was modelled in detail. Fluxes and energy-deposition rates for neutrons, recoil ions, photons, and fast electrons have been calculated using MCNP4B, WIMS-AECL, and specifically derived energy-transfer factors. These factors generate the energy/flux spectra of recoil ions from fast-neutron energy/flux spectra. The energy spectrum was divided into 89 discrete ranges (energy bins).The production of oxidizing species and net coolant radiolysis can be suppressed by the addition of hydrogen to the coolant of nuclear reactors. It is argued that the net dissociation of coolant by gamma rays is suppressed by lower levels of excess hydrogen than when dissociation is by ion recoils. This has consequences for the modelling of coolant radiolysis by homogeneous kinetics. More added hydrogen is required to stop water radiolysis by recoil ions acting alone than if recoil ions and gamma rays acted concurrently in space and time. Homogeneous kinetic models and experimental data suggest that track overlap is very inefficient in providing radicals from gamma-ray tracks to recombine molecular products in ion-recoil tracks. An inhomogeneous chemical model is needed that incorporates ionizing-particle track structure and track overlap. Such a model does not yet exist, but a number of limiting cases using homogeneous kinetics are discussed. There are sufficient uncertainties and contradictions in the data relevant to the radiolysis of reactor coolant that the relatively high CHC's (critical hydrogen concentration) observed in NRU reactor experiments (compared to model predictions) may be explainable by errors in fundamental data and understanding of water radiolysis under reactor conditions. The radiation chemistry program at CRL has been focused to generate quantitative water-radiolysis data in a

  5. The chemistry and isotopic composition of waters in the low-enthalpy geothermal system of Cimino-Vico Volcanic District, Italy

    DEFF Research Database (Denmark)

    Battistel, Maria; Hurwitz, Shaul; Evans, William C.

    2016-01-01

    Geothermal energy exploration is based in part on interpretation of the chemistry, temperature, and discharge rate of thermal springs. Here we present the major element chemistry and the δD, δ18O, 87Sr/86Sr and δ11B isotopic ratio of groundwater from the low-enthalpy geothermal system near the city...... of Viterbo in the Cimino-Vico volcanic district of west-Central Italy. The geothermal system hosts many thermal springs and gas vents, but the resource is still unexploited. Water chemistry is controlled by mixing between low salinity,HCO3-rich fresh waters (... and SO4-rich thermal waters (25.3 °C to 62.2 °C) ascending from deep, high permeability Mesozoic limestones. The (equivalent) SO4/Cl (0.01–0.02), Na/Cl (2.82–5.83) and B/Cl ratios (0.02–0.38) of thermal waters differs from the ratios in other geothermal systems from Central Italy, probably implying...

  6. Improving Student Attitudes about Science by Integrating Research into the Introductory Chemistry Laboratory: Interdisciplinary Drinking Water Analysis

    Science.gov (United States)

    Richter-Egger, Dana L.; Hagen, James P.; Laquer, Frederic C.; Grandgenett, Neal F.; Shuster, Robert D.

    2010-01-01

    The integration of student research into a general chemistry laboratory and an environmental geology course has been evaluated for its effectiveness to improve (i) student attitudes about science and chemistry, (ii) student understanding of the nature of experimental science and the scientific method, and (iii) student perceptions of the…

  7. Multi-linear regression analysis, preliminary biotic ligand modeling, and cross species comparison of the effects of water chemistry on chronic lead toxicity in invertebrates.

    Science.gov (United States)

    Esbaugh, A J; Brix, K V; Mager, E M; De Schamphelaere, K; Grosell, M

    2012-03-01

    The current study examined the chronic toxicity of lead (Pb) to three invertebrate species: the cladoceran Ceriodaphnia dubia, the snail Lymnaea stagnalis and the rotifer Philodina rapida. The test media consisted of natural waters from across North America, varying in pertinent water chemistry parameters including dissolved organic carbon (DOC), calcium, pH and total CO(2). Chronic toxicity was assessed using reproductive endpoints for C. dubia and P. rapida while growth was assessed for L. stagnalis, with chronic toxicity varying markedly according to water chemistry. A multi-linear regression (MLR) approach was used to identify the relative importance of individual water chemistry components in predicting chronic Pb toxicity for each species. DOC was an integral component of MLR models for C. dubia and L. stagnalis, but surprisingly had no predictive impact on chronic Pb toxicity for P. rapida. Furthermore, sodium and total CO(2) were also identified as important factors affecting C. dubia toxicity; no other factors were predictive for L. stagnalis. The Pb toxicity of P. rapida was predicted by calcium and pH. The predictive power of the C. dubia and L. stagnalis MLR models was generally similar to that of the current C. dubia BLM, with R(2) values of 0.55 and 0.82 for the respective MLR models, compared to 0.45 and 0.79 for the respective BLMs. In contrast the BLM poorly predicted P. rapida toxicity (R(2)=0.19), as compared to the MLR (R(2)=0.92). The cross species variability in the effects of water chemistry, especially with respect to rotifers, suggests that cross species modeling of invertebrate chronic Pb toxicity using a C. dubia model may not always be appropriate. Copyright © 2011 Elsevier Inc. All rights reserved.

  8. A multivariate statistical analysis of surface water chemistry data--the Ankobra Basin, Ghana.

    Science.gov (United States)

    Yidana, Sandow M; Ophori, Duke; Banoeng-Yakubo, Bruce

    2008-01-01

    R-mode hierarchical cluster and principal component analysis (PCA) were simultaneously applied to surface water hydrochemical data from three different locations, Ankwaso, Dominase and Prestea, along the Ankobra Basin, Ghana, to extract principal factors corresponding to the different sources of variation in the hydrochemistry, with the objective of defining the main controls on the hydrochemistry at the basin scale. Using the Kaiser criterion, principal components (PC) were extracted from the data and rotated using varimax normalization, for each location. The varimax rotation ensured that variation in the data was maximized for easy interpretation of the results. The analysis reduced 30, 33 and 33 data points, respectively, for Ankwaso, Dominase and Prestea to four, three and four PC representing the sources of variation in the hydrochemistry at the three different locations. Though the PC analysis proved to be more robust at unveiling the sources of variation in the hydrochemistry than the R-mode hierarchical cluster analysis (HCA), the combined use of both techniques resulted in more reliable interpretations of the hydrochemistry. On the basis of these analyses, the hydrochemistry of the basin is controlled largely by the weathering of minerals (silicates, carbonates, gypsum and apatite) from the underlying meta-sediments of the Birimian and Tarkwaian Systems, and the decay of organic matter from the heavily forested regions. Concentrations of the major chemical parameters are within naturally acceptable limits and do not pose threats to the local ecology and humans. There is no strong evidence of high anthropogenic impacts on the major anions and cations used for this research, though there are variations at the different locations studied. The hydrochemistry at Ankwaso is principally controlled by the weathering of silicate minerals, whereas those of Dominase and Prestea are, respectively, influenced by precipitation and domestic wastewaters, and the decay of

  9. The Tianjin geothermal field (north-eastern China): Water chemistry and possible reservoir permeability reduction phenomena

    Energy Technology Data Exchange (ETDEWEB)

    Minissale, Angelo; Montegrossi, Giordano; Orlando, Andrea [Institute of Geosciences and Earth Resources, National Research Council of Italy (CNR), Via G. La Pira 4, 50121 Florence (Italy); Borrini, Daniele; Tassi, Franco [Department of Earth Sciences, University of Florence, Via G. La Pira 4, 50121 Florence (Italy); Vaselli, Orlando [Institute of Geosciences and Earth Resources, National Research Council of Italy (CNR), Via G. La Pira 4, 50121 Florence (Italy); Department of Earth Sciences, University of Florence, Via G. La Pira 4, 50121 Florence (Italy); Huertas, Antonio Delgado [Estacion Experimental de Zaidin (CSIC), Prof. Albareda 1, 18008 Granada (Spain); Yang, Jincheng; Cheng, Wanquing [Aode Renewable Energy Research Institute, 90 Weijin South Road, Nankai District, 300381 Tianjin (China); Tedesco, Dario [Department of Environmental Sciences, Second University of Naples, Via Vivaldi 43, Caserta 81100 (Italy); Institute of Environmental Geology and Geo Engineering (CNR), Piazzale A. Moro 5, Roma 00100 (Italy); Poreda, Robert [Department of Earth and Environmental Sciences, University of Rochester, 227 Hutchison Hall, Rochester, NY 14627 (United States)

    2008-08-15

    Injection of spent (cooled) thermal fluids began in the Tianjin geothermal district, north-eastern China, at the end of the 1990s. Well injectivities declined after 3-4 years because of self-sealing processes that reduced reservoir permeability. The study focuses on the factors that may have caused the observed decrease in permeability, using chemical and isotopic data on fluids (water and gas) and mineral phases collected from production and injection wells. The results of data processing and interpretation indicate that (1) it is very unlikely that calcite and silica precipitation is taking place in the reservoir; (2) the Fe- and Zn-rich mineral phases (e.g. sulfides, hydroxides and silicates) show positive saturation indexes; (3) SEM and XRD analyses of filtered material reveal that the latter mineral phases are common; (4) visual observation of casings and surface installations, and of corrosion products, suggests that a poor quality steel was used in their manufacture; (5) significant quantities of solids (e.g. quartz and feldspar crystals) are carried by the geothermal fluid; (6) seasonal changes in fluid composition lead to a reduction in casing corrosion during the summer. It was concluded that the decrease in injectivity in the Tianjin wells is caused only in part by the oxidation of casings, downhole pumps, and surface installations, triggered by free oxygen in the injected fluids; the utilization of better quality steels should drastically reduce this type of corrosion. Self-sealing of pores and fractures by reservoir formation solids and by the Fe-corrosion products suspended in the injected fluids seems to be a more important phenomenon, whose effect could be greatly reduced by installing filtering devices at all sites. (author)

  10. Area G perimeter surface-soil and single-stage water sampling: Environmental surveillance for fiscal year 1993

    Energy Technology Data Exchange (ETDEWEB)

    Conrad, R.; Childs, M.; Rivera-Dirks, C.; Coriz, F.

    1995-07-01

    Area G, in Technical Area 54, has been the principle facility at Los Alamos National Laboratory for the storage and disposal of low-level and transuranic (TRU) radioactive wastes since 1957. The current environmental investigation consisted of ESH-19 personnel who collected soil and single-stage water samples around the perimeter of Area G to characterize possible contaminant movement through surface-water runoff. These samples were analyzed for tritium, total uranium, isotopic plutonium, americium-241 (soil only), and cesium 137. The metals, mercury, lead, and barium, were analyzed using x-ray fluorescence.

  11. Contrasting roles of water chemistry, lake morphology, land-use, climate and spatial processes in driving phytoplankton richness in the Danish landscape

    DEFF Research Database (Denmark)

    Özkan, Korhan; Jeppesen, Erik; Søndergaard, Martin

    2013-01-01

    were performed on permuted data 1,000 times. The local environment was described by lake water chemistry, lake morphology, land-use in lake catchments, and climate. Analysis of the effects of four groups of environmental factors on the richness of the main groups of phytoplankton revealed contrasting...... patterns. Lake water chemistry was the strongest predictor of phytoplankton richness for all groups, while lake morphology also had a strong influence on Bacillariophyceae, Cyanobacteria, Dinophyceae, and Euglenophyceae richness. Climate and land-use in catchments contributed only little to the explained...... variation in phytoplankton richness, although both factors had a significant effect on Bacillariophyceae richness. Notably, total nitrogen played a more important role for phytoplankton richness than total phosphorus. Overall, models accounted for ca. 30% of the variation in genus richness for all...

  12. A synthesis of atmospheric mercury depletion event chemistry linking atmosphere, snow and water

    Science.gov (United States)

    Steffen, A.; Douglas, T.; Amyot, M.; Ariya, P.; Aspmo, K.; Berg, T.; Bottenheim, J.; Brooks, S.; Cobbett, F.; Dastoor, A.; Dommergue, A.; Ebinghaus, R.; Ferrari, C.; Gardfeldt, K.; Goodsite, M. E.; Lean, D.; Poulain, A.; Scherz, C.; Skov, H.; Sommar, J.; Temme, C.

    2007-07-01

    It was discovered in 1995 that, during the spring time, unexpectedly low concentrations of gaseous elemental mercury (GEM) occurred in the Arctic air. This was surprising for a pollutant known to have a long residence time in the atmosphere; however conditions appeared to exist in the Arctic that promoted this depletion of mercury (Hg). This phenomenon is termed atmospheric mercury depletion events (AMDEs) and its discovery has revolutionized our understanding of the cycling of Hg in Polar Regions while stimulating a significant amount of research to understand its impact to this fragile ecosystem. Shortly after the discovery was made in Canada, AMDEs were confirmed to occur throughout the Arctic, sub-Artic and Antarctic coasts. It is now known that, through a series of photochemically initiated reactions involving halogens, GEM is converted to a more reactive species and is subsequently associated to particles in the air and/or deposited to the polar environment. AMDEs are a means by which Hg is transferred from the atmosphere to the environment that was previously unknown. In this article we review the history of Hg in Polar Regions, the methods used to collect Hg in different environmental media, research results of the current understanding of AMDEs from field, laboratory and modeling work, how Hg cycles around the environment after AMDEs, gaps in our current knowledge and the future impacts that AMDEs may have on polar environments. The research presented has shown that while considerable improvements in methodology to measure Hg have been made the main limitation remains knowing the speciation of Hg in the various media. The processes that drive AMDEs and how they occur are discussed. As well, the roles that the snow pack, oceans, fresh water and the sea ice play in the cycling of Hg are presented. It has been found that deposition of Hg from AMDEs occurs at marine coasts and not far inland and that a fraction of the deposited Hg does not remain in the same

  13. Wood-ash addition on a drained forest peatland in Southern Sweden - Effects on water chemistry; Tillfoersel av biobra ensleaska i tallskog paa en dikad torvmark i soedra Sverige - Effekter paa vattenkemin

    Energy Technology Data Exchange (ETDEWEB)

    Ring, Eva; Broemssen, Claudia von; Losjoe, Katarina; Sikstroem Ulf

    2012-02-15

    Wood ash can be used for forest fertilization on peatlands or for nutrient compensation following intensive harvesting. This project was performed in order to investigate effects on water chemistry of applying wood ash to a Scots pine stand on a drained peatland. Ditch-water chemistry was monitored before and after the application of wood ash. Furthermore, groundwater was collected and chemically analyzed both from the ash-treated peatland and from an adjacent untreated reference peatland. Both short term (a few months) and more long term effects (up to three years after application) were detected on water chemistry

  14. Deposition kinetics of quantum dots and polystyrene latex nanoparticles onto alumina: role of water chemistry and particle coating.

    Science.gov (United States)

    Quevedo, Ivan R; Olsson, Adam L J; Tufenkji, Nathalie

    2013-03-05

    A clear understanding of the factors controlling the deposition behavior of engineered nanoparticles (ENPs), such as quantum dots (QDs), is necessary for predicting their transport and fate in natural subsurface environments and in water filtration processes. A quartz crystal microbalance with dissipation monitoring (QCM-D) was used to study the effect of particle surface coatings and water chemistry on the deposition of commercial QDs onto Al2O3. Two carboxylated QDs (CdSe and CdTe) with different surface coatings were compared with two model nanoparticles: sulfate-functionalized (sPL) and carboxyl-modified (cPL) polystyrene latex. Deposition rates were assessed over a range of ionic strengths (IS) in simple electrolyte (KCl) and in electrolyte supplemented with two organic molecules found in natural waters; namely, humic acid and rhamnolipid. The Al2O3 collector used here is selected to be representative of oxide patches found on the surface of aquifer or filter grains. Deposition studies showed that ENP deposition rates on bare Al2O3 generally decreased with increasing salt concentration, with the exception of the polyacrylic-acid (PAA) coated CdTe QD which exhibited unique deposition behavior due to changes in the conformation of the PAA coating. QD deposition rates on bare Al2O3 were approximately 1 order of magnitude lower than those of the polystyrene latex nanoparticles, likely as a result of steric stabilization imparted by the QD surface coatings. Adsorption of humic acid or rhamnolipid on the Al2O3 surface resulted in charge reversal of the collector and subsequent reduction in the deposition rates of all ENPs. Moreover, the ratio of the two QCM-D output parameters, frequency and dissipation, revealed key structural information of the ENP-collector interface; namely, on bare Al2O3, the latex particles were rigidly attached as compared to the more loosely attached QDs. This study emphasizes the importance of considering the nature of ENP coatings as well

  15. Environmental surveillance master sampling schedule

    Energy Technology Data Exchange (ETDEWEB)

    Bisping, L.E.

    1994-02-01

    This document contains the planned 1994 schedules for routine collection of samples for the Surface Environmental Surveillance Project (SESP), Drinking Water Project, and Ground-Water Surveillance Project. Samples are routinely collected for the SESP and analyzed to determine the quality of air, surface water, soil, sediment, wildlife, vegetation, foodstuffs, and farm products at Hanford Site and surrounding communities. The responsibility for monitoring the onsite drinking water falls outside the scope of the SESP. The Hanford Environmental Health Foundation is responsible for monitoring the nonradiological parameters as defined in the National Drinking Water Standards while PNL conducts the radiological monitoring of the onsite drinking water. PNL conducts the drinking water monitoring project concurrent with the SESP to promote efficiency and consistency, utilize the expertise developed over the years, and reduce costs associated with management, procedure development, data management, quality control and reporting. The ground-water sampling schedule identifies ground-water sampling events used by PNL for environmental surveillance of the Hanford Site.

  16. Surveillance of Enteric Viruses and Microbial Indicators in the Eastern Oysters (Crassostrea virginica) and Harvest Waters along Louisiana Gulf Coast.

    Science.gov (United States)

    Montazeri, Naim; Maite, Morgan; Liu, Da; Cormier, Jiemin; Landry, Matthew; Shackleford, John; Lampila, Lucina E; Achberger, Eric C; Janes, Marlene E

    2015-05-01

    Noroviruses are the most common causative agent of viral gastroenteritis in humans, and are responsible for major foodborne illnesses in the United States. Filter-feeding molluscan shellfish exposed to sewage-contaminated waters bioaccumulate viruses, and if consumed raw, transmit the viruses to humans and cause illness. We investigated the occurrence of norovirus GI and GII and microbial indicators of fecal contamination in the eastern oysters (Crassostrea virginica) and water from commercial harvesting areas along the Louisiana Gulf Coast (January to November of 2013). Microbial indicators (aerobic plate count, enterococci, fecal coliforms, Escherichia coli, male-specific coliphages, and somatic coliphages) were detected at the densities lower than public health concerns. Only one oyster sample was positive for norovirus GII at 3.5 ± 0.2 log10 genomic equivalent copies/g digestive tissues. A stool specimen obtained from an infected individual associated with a norovirus outbreak and the suspected oysters (Cameron Parish, La., area 30, January 2013) were also analyzed. The norovirus strain in the stool belonged to GII.4 Sydney; however, the oysters were negative and could not be linked. In general, no temporal trend was observed in the microbial indicators. Low correlation among bacterial indicators was observed in oysters. Strongest correlations among microbial indicators were observed between enterococci and fecal coliforms (r = 0.63) and between enterococci and E. coli (r = 0.64) in water (P oysters (r oysters and harvest water (r ≤ 0.36, P > 0.05). Our results emphasize the need for regular monitoring of pathogenic viruses in commercial oyster harvesting areas to reduce the risks of viral gastroenteritis incidences. © 2015 Institute of Food Technologists®

  17. RETENTION OF HUMIC ACID FROM WATER BY NANOFILTRATION MEMBRANE AND INFLUENCE OF SOLUTION CHEMISTRY ON MEMBRANE PERFORMANCE

    Directory of Open Access Journals (Sweden)

    M. A. Zazouli, S. Nasseri, A. H. Mahvi, M. Gholami, A. R. Mesdaghinia, M. Younesian

    2008-01-01

    Full Text Available The objectives of this research were to investigate the rejection efficiency of salt and hydrophobic fraction of natural organic matter, to study the flux decline behavior with a spiral wound nanofiltration membrane, and also to survey the influence of water chemistry on membrane performance. Experiments were conducted using a cross flow pilot-scale membrane unit with a full circulation mode. Humic acid was used as hydrophobic organic matter and NaCl as background electrolyte. Results showed that flux reduction increased with increasing ionic strength and humic acid concentration, and with lower pH. The rejection efficiency of organic and salt decreased with the decrease in pH and increase in ionic strength, because of osmotic pressure increase, leading to permeate flux decline and decrease in salt rejection. In addition, the improved salt rejection was likely due to Donnan exclusion by humic material close to membrane surfaces. The average rejection efficiency of humic acid and salt ranged between 91.2%-95.25% and 63.6%-80%, respectively. Dissolved organic carbon concentration was less than 0.57mg/L in permeate for all experiments. With increasing organic concentration, the charge of the membrane surface has become more negative due to the adsorption of organic foulants on the membrane surface, and thus increased the electrostatic repulsion. However, the increasing surface charge had the potential to result in a larger molecular weight cut-off of a fouled membrane due to membrane swelling which can lead to lower rejection solutes. Therefore, results of this study indicated that membrane fouling may significantly affect the rejection of organic and ion solute.

  18. Physical and biological controls on the carbonate chemistry of coral reef waters: effects of metabolism, wave forcing, sea level, and geomorphology.

    Science.gov (United States)

    Falter, James L; Lowe, Ryan J; Zhang, Zhenlin; McCulloch, Malcolm

    2013-01-01

    We present a three-dimensional hydrodynamic-biogeochemical model of a wave-driven coral-reef lagoon system using the circulation model ROMS (Regional Ocean Modeling System) coupled with the wave transformation model SWAN (Simulating WAves Nearshore). Simulations were used to explore the sensitivity of water column carbonate chemistry across the reef system to variations in benthic reef metabolism, wave forcing, sea level, and system geomorphology. Our results show that changes in reef-water carbonate chemistry depend primarily on the ratio of benthic metabolism to the square root of the onshore wave energy flux as well as on the length and depth of the reef flat; however, they are only weakly dependent on channel geometry and the total frictional resistance of the reef system. Diurnal variations in pCO(2), pH, and aragonite saturation state (Ω(ar)) are primarily dependent on changes in net production and are relatively insensitive to changes in net calcification; however, net changes in pCO(2), pH, and Ω(ar) are more strongly influenced by net calcification when averaged over 24 hours. We also demonstrate that a relatively simple one-dimensional analytical model can provide a good description of the functional dependence of reef-water carbonate chemistry on benthic metabolism, wave forcing, sea level, reef flat morphology, and total system frictional resistance. Importantly, our results indicate that any long-term (weeks to months) net offsets in reef-water pCO(2) relative to offshore values should be modest for reef systems with narrow and/or deep lagoons. Thus, the long-term evolution of water column pCO(2) in many reef environments remains intimately connected to the regional-scale oceanography of offshore waters and hence directly influenced by rapid anthropogenically driven increases in pCO(2).

  19. Physical and biological controls on the carbonate chemistry of coral reef waters: effects of metabolism, wave forcing, sea level, and geomorphology.

    Directory of Open Access Journals (Sweden)

    James L Falter

    Full Text Available We present a three-dimensional hydrodynamic-biogeochemical model of a wave-driven coral-reef lagoon system using the circulation model ROMS (Regional Ocean Modeling System coupled with the wave transformation model SWAN (Simulating WAves Nearshore. Simulations were used to explore the sensitivity of water column carbonate chemistry across the reef system to variations in benthic reef metabolism, wave forcing, sea level, and system geomorphology. Our results show that changes in reef-water carbonate chemistry depend primarily on the ratio of benthic metabolism to the square root of the onshore wave energy flux as well as on the length and depth of the reef flat; however, they are only weakly dependent on channel geometry and the total frictional resistance of the reef system. Diurnal variations in pCO(2, pH, and aragonite saturation state (Ω(ar are primarily dependent on changes in net production and are relatively insensitive to changes in net calcification; however, net changes in pCO(2, pH, and Ω(ar are more strongly influenced by net calcification when averaged over 24 hours. We also demonstrate that a relatively simple one-dimensional analytical model can provide a good description of the functional dependence of reef-water carbonate chemistry on benthic metabolism, wave forcing, sea level, reef flat morphology, and total system frictional resistance. Importantly, our results indicate that any long-term (weeks to months net offsets in reef-water pCO(2 relative to offshore values should be modest for reef systems with narrow and/or deep lagoons. Thus, the long-term evolution of water column pCO(2 in many reef environments remains intimately connected to the regional-scale oceanography of offshore waters and hence directly influenced by rapid anthropogenically driven increases in pCO(2.

  20. Effects of low-level radioactive-waste disposal on water chemistry in the unsaturated zone at a site near Sheffield, Illinois, 1982-84

    Science.gov (United States)

    Peters, C.A.; Striegl, Robert G.; Mills, P.C.; Healy, R.W.

    1992-01-01

    A 1982-84 field study defined the chemistry of water collected from the unsaturated zone at a low-level radioactive-waste disposal site near Sheffield, Bureau County, Illinois. Chemical data were evaluated to determine the principal naturally occurring geochemical reactions in the unsaturated zone and to evaluate waste-induced effects on pore-water chemistry. Samples of precipitation, unsaturated-zone pore water, and saturated-zone water were analyzed for specific conductance, pH, alkalinity, major cations and anions, dissolved organic carbon, gross alpha and beta radiation, and tritium. Little change in concentration of most major constituents in the unsaturated-zone water was observed with respect to depth or distance from disposal trenches. Tritium and dissolved organic carbon concentrations were, however, dependent on proximity to trenches. The primary reactions, both on- site and off-site, were carbonate and clay dissolution, cation exchange, and the oxidation of pyrite. The major difference between on-site and off-site inorganic water chemistry resulted from the removal of the Roxana Silt and the Radnor Till Member of the Glasford Formation from on-site. Off-site, the Roxana Silt contributed substantial quantities of sodium to solution from montmorillonite dissolution and associated cation-exchange reactions. The Radnor Till Member provided exchange surfaces for magnesium. Precipitation at the site had an ionic composition of calcium zinc sulfate and an average pH of 4.6. Within 0.3 meter of the land surface, infiltrating rain water or snowmelt changed to an ionic canposition of calcium sulfate off-site and calcium bicarbonate on-site and had an average pH of 7.9; below that depth, pH averaged 7.5 and the ionic composition generally was calcium magnesium bicarbonate. Alkalinity and specific conductance differed primarily according to composition of geologic materials. Tritium concentrations ranged from 0.2 (detection limit) to 1,380 nanocuries per liter. The

  1. Can radiation chemistry supply a highly efficient AO(R)P process for organics removal from drinking and waste water? A review.

    Science.gov (United States)

    Trojanowicz, Marek; Bojanowska-Czajka, Anna; Capodaglio, Andrea G

    2017-09-01

    The increasing role of chemistry in industrial production and its direct and indirect impacts in everyday life create the need for continuous search and efficiency improvement of new methods for decomposition/removal of different classes of waterborne anthropogenic pollutants. This review paper addresses a highly promising class of water treatment solutions, aimed at tackling the pressing problem of emerging contaminants in natural and drinking waters and wastewater discharges. Radiation processing, a technology originating from radiation chemistry studies, has shown encouraging results in the treatment of (mainly) organic water pollution. Radiation ("high energy") processing is an additive-free technology using short-lived reactive species formed by the radiolysis of water, both oxidative and reducing, to carry out decomposition of organic pollutants. The paper illustrates the basic principles of radiolytic treatment of organic pollutants in water and wastewaters and specifically of one of its most practical implementations (electron beam processing). Application examples, highlighting the technology's strong points and operational conditions are described, and a discussion on the possible future of this technology follows.

  2. The Effect of Water Chemistry on Thermochemical Sulfate Reduction: A Case Study from the Ordovician in the Tazhong Area, Northwest China

    Directory of Open Access Journals (Sweden)

    Hongxia Li

    2017-01-01

    Full Text Available Formation water chemistry, sulfate sulfur isotopes, and associated H2S contents and sulfur isotopes were measured from the Ordovician in Tazhong area, Tarim Basin. The aim is to elucidate the effects of geochemical composition of formation water on thermochemical sulfate reduction (TSR and potential usage of SO4/Cl ratios as a new proxy for TSR extents in areas, where H2S and thiaadamantanes (TAs data are not available. The formation water has SO4/Cl ratios from 0.0002 to 0.016, significantly lower than 0.04 to 0.05 from 3 to 7 times evapoconcentrated seawater. Thus, the low values are explained to result from TSR. Furthermore, the SO4/Cl ratios show negative correlation relationships to TAs and H2S concentrations, indicating that TSR occurred in a relatively closed system and SO4/Cl ratio can be used to indicate TSR extents in this area. Extensive TSR in the Cambrian in the Tazhong area, represented by low SO4/Cl ratios and high H2S and TAs concentrations, is accompanied by formation water with high TDS and Mg concentrations, indicating the effects of water chemistry on TSR under a realistic geological background. In contrast, the low TSR extent in the Ordovician may have resulted from limited TSR reaction duration and total contribution of aqueous SO42-.

  3. Water physics and chemistry data from moored current meter and bottle casts in the Northwest Atlantic Ocean as part of the North East Monitoring Program (NEMP) project, 03 June 1981 - 09 June 1981 (NODC Accession 8100724)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Water physics and chemistry data were collected using moored current meter and bottle casts in the Northwest Atlantic Ocean from June 3, 1981 to June 9, 1981. Data...

  4. Water physics and chemistry data from bottle casts from MULTIPLE SHIPS and other platforms from the NW Atlantic (limit-40 W) from 1951-01-10 to 1957-04-18 (NODC Accession 7200385)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Water physics and chemistry data were collected from bottle casts from MULTIPLE SHIPS and other platforms from NW Atlantic (limit-40 W) from 10 January 1951 to 18...

  5. Water physics and chemistry data from moored current meter and bottle casts in the Northwest Atlantic Ocean as part of the North East Monitoring Program (NEMP) project, 09 September 1981 - 14 September 1981 (NODC Accession 8200051)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Water physics and chemistry data were collected using moored current meter and bottle casts in the Northwest Atlantic Ocean from September 9, 1981 to September 14,...

  6. Water physics and chemistry data from moored current meter and bottle casts in the Gulf of Mexico as part of the Brine Disposal project, 03 June 1978 - 02 June 1979 (NODC Accession 8000244)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Water physics and chemistry data were collected using moored current meter and bottle casts in the Gulf of Mexico from June 3, 1978 to June 2, 1979. Data were...

  7. Water physics and chemistry data from moored current meter and bottle casts in the Gulf of Mexico as part of the Brine Disposal project, 04 December 1979 - 11 June 1980 (NODC Accession 8000476)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Water physics and chemistry data were collected using moored current meter and bottle casts in the Gulf of Mexico from December 4, 1979 to June 11, 1980. Data were...

  8. Water physics and chemistry data from moored current meter and bottle casts in the Gulf of Mexico as part of the Brine Disposal project, 20 November 1980 - 16 March 1981 (NODC Accession 8100530)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Water physics and chemistry data were collected using moored current meter and bottle casts in the Gulf of Mexico from November 20, 1980 to March 16, 1981. Data were...

  9. Water physics and chemistry data from moored current meter and bottle casts in the New York Bight as part of the North East Monitoring Program (NEMP) project, 10 April 1984 - 31 October 1984 (NODC Accession 8500225)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Water physics and chemistry data were collected using moored current meter and bottle casts in the New York Bight from April 10, 1984 to October 31, 1984. Data were...

  10. Water physics and chemistry data from moored current meter and bottle casts in the Northwest Atlantic Ocean as part of the North East Monitoring Program (NEMP) project, 01 August 1981 - 07 August 1981 (NODC Accession 8200028)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Water physics and chemistry data were collected using moored current meter and bottle casts in the Northwest Atlantic Ocean from August 1, 1981 to August 7, 1981....

  11. Water physics and chemistry data from moored current meter and bottle casts in the Northwest Atlantic Ocean as part of the North East Monitoring Program (NEMP) project, 20 April 1982 - 24 April 1982 (NODC Accession 8300034)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Water physics and chemistry data were collected using moored current meter and bottle casts in the Northwest Atlantic Ocean from August 1, 1981 to August 7, 1981....

  12. Water physics and chemistry data from moored current meter and bottle casts in the Northwest Atlantic Ocean as part of the North East Monitoring Program (NEMP) project, 21 April 1980 - 18 July 1980 (NODC Accession 8100501)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Water physics and chemistry data were collected using moored current meter and bottle casts in the Northwest Atlantic Ocean from April 21, 1980 to July 18, 1980....

  13. Active surveillance of the aquatic environment for potential prediction, prevention and spread of water borne disease: the cholera paradigm

    Science.gov (United States)

    Huq, A.; Colwell, R.

    2011-12-01

    Based on results of ecological and epidemiological studies, occurrence and spread of certain diseases are more fully understood. Cholera is a major waterborne disease, that is relatively easily treatable and clearly preventable, yet tens of thousands die each year worldwide. A dose dependent disease, the infectious dose can vary from 103-106, depending on health status of the victim. Historically, cholera has been shown to spread from person to person. Furthermore, the disease is caused predominantly via ingestion of contaminated water and most of the outbreaks that have been recorded worldwide originated in a coastal region. Using appropriate detection methods, Vibrio cholerae can be isolated from samples collected from ponds, rivers, estuaries, and coastal waters globally. The populations of V. cholerae may vary in numbers during different seasons of the year. It is important to have a clear understanding of the distribution of the causative agent in the environment as such information can assist public health officials in taking action to prevent outbreaks of cholera. Thus an effective monitoring program is critical, particularly in light of climate change with temperature extremes more likely to be occurring. Based on a predictive model and results of ground truth data, temperature has been found to be a factor in the increase of V. cholerae in the environment. Correlation was observed with occurrence of cholera and both temperature and salinity. More recent research indicates additional factors need to be considered in predicting cholera epidemics, including the hydrology and disease dynamics.

  14. [Epidemiological surveillance of dental fluorosis in a city with a tropical climate with a fluoridated public drinking water supply].

    Science.gov (United States)

    de Moura, Marcoeli Silva; Barbosa, Pablo Renan Ribeiro; Nunes-Dos-Santos, Danila Lorena; Dantas-Neta, Neusa Barros; Moura, Lúcia de Fátima Almeida de Deus; de Lima, Marina de Deus Moura

    2016-04-01

    The scope of this study was to evaluate the prevalence and severity of dental fluorosis among 11 to 14-year-old schoolchildren in Teresina, Piauí, Brazil, which is a tropical city with a fluoridated public drinking water supply. It involved a cross-sectional observational study on a sample of 571 students in public and private schools. Informed Consent forms were approved for the data collection and the exams were conducted at the schools. Data were recorded on a questionnaire answered by the parents, regarding the socioeconomic and demographic characteristics and oral hygiene habits of the sample. The dental exam was performed qualified dental sugeons. The Thylstrup-Fejerskov (TF) index was used. The prevalence of fluorosis was 77.9%, and only 12.5% of the affected children had TF ≥ grade 3 (with aesthetic damage). The premolars were the teeth most affected by fluorosis. Among the students with the highest severity of fluorosis, 98.6% belonged to the lowest social bracket (> B2), 91.5% were born and had always lived in Teresina, 94.4% consumed water from the fluoridated public supply, 76% used toothpaste for children and 64% of mothers reported that they swallowed toothpaste. The prevalence of fluorosis was high, though the severity was low in individuals exposed to fluoridation since birth.

  15. Who is Surveilling Whom?

    DEFF Research Database (Denmark)

    Mortensen, Mette

    2014-01-01

    This article concerns the particular form of counter-surveillance termed “sousveillance”, which aims to turn surveillance at the institutions responsible for surveillance. Drawing on the theoretical perspectives “mediatization” and “aerial surveillance,” the article studies WikiLeaks’ publication...

  16. [Surveillance and forecast system of schistosomiasis in Jiangsu Province. VI. Detection technology of water infectivity based on enrichment of Schistosoma japonicum cercariae on water surface].

    Science.gov (United States)

    Qu, Guo-li; Dai, Jian-rong; Xing, Yuan-tian; Wang, Wei; Yang, Zhen-kun; Zhao, Zheng-yang; Guo, Na; Sun, Le-ping; Liang, You-Sheng

    2014-10-01

    To explore the enrichment technique of Schistosoma japonicum cercariae on the water surface, so as to establish a new method combined with the existing technology to detect the cercarial infested water body quickly and sensitively. Soybean oil, gasoline, kerosene and isophorone were screened as expanding agents. The cercariae were enriched by the thrust of the expanding agents when diffusing on the water surface, and PE adsorption film and C-6 film were applied to seize them so as to determine the infectivity of the water quickly. The relationship between the dose of expanding agents and diffusion radius were explored. Gasoline, kerosene and isophorone were suitable expanding agents, and the diffusion effect of isophorone was the best. After the enrichment by the expanding agents, the detection rate of cercariae of the method seizing cercariae with the film significantly improved in the water. This new method could effectively improve the detection rate of the cercarial infested water and is suitable for the low-degree infested water.

  17. Response of surface water chemistry to reduced levels of acid precipitation: Comparison of trends in two regions of New York, USA

    Science.gov (United States)

    Burns, Douglas A.; McHale, M.R.; Driscoll, C.T.; Roy, K.M.

    2006-01-01

    In light of recent reductions in sulphur (S) and nitrogen (N) emissions mandated by Title IV of the Clean Air Act Amendments of 1990, temporal trends and trend coherence in precipitation (1984-2001 and 1992-2001) and surface water chemistry (1992-2001) were determined in two of the most acid-sensitive regions of North America, i.e. the Catskill and Adirondack Mountains of New York. Precipitation chemistry data from six sites located near these regions showed decreasing sulphate (SO42-), nitrate (NO3-), and base cation (CB) concentrations and increasing pH during 1984-2001, but few significant trends during 1992-2001. Data from five Catskill streams and 12 Adirondack lakes showed decreasing trends in SO42- concentrations at all sites, and decreasing trends in NO3-, CB, and H+ concentrations and increasing trends in dissolved organic carbon at most sites. In contrast, acid-neutralizing capacity (ANC increased significantly at only about half the Adirondack lakes and in one of the Catskill streams. Flow correction prior to trend analysis did not change any trend directions and had little effect on SO42- trends, but it caused several significant non-flow-corrected trends in NO3- and ANC to become non-significant, suggesting that trend results for flow-sensitive constituents are affected by flow-related climate variation. SO42- concentrations showed high temporal coherence in precipitation, surface waters, and in precipitation-surface water comparisons, reflecting a strong link between S emissions, precipitation SO42- concentrations, and the processes that affect S cycling within these regions. NO3- and H+ concentrations and ANC generally showed weak coherence, especially in surface waters and in precipitation-surface water comparisons, indicating that variation in local-scale processes driven by factors such as climate are affecting trends in acid-base chemistry in these two regions. Copyright ?? 2005 John Wiley & Sons, Ltd.

  18. Effects of low-level radioactive-waste disposal on water chemistry in the unsaturated zone at a site near Sheffield, Illinois, 1982-84

    Science.gov (United States)

    Peters, C.A.; Striegl, R.G.; Mills, P.C.; Healy, R.W.

    1992-01-01

    A 1982-84 field study defined the chemistry of water collected from the unsaturated zone at a low-level radioactive-waste disposal site near Sheffield, Bureau County, Ill. Chemical data were evaluated to determine the principal, naturally occurring geochemical reactions in the unsaturated zone and to evaluate waste-induced effects on pore-water chemistry. Samples of precipitation, unsaturated-zone pore water, and saturated-zone water were analyzed for specific conductance, pH, alkalinity, major cations and anions, dissolved organic carbon, gross alpha and beta radiation, and tritium. Little change in concentration of most major constituents in the unsaturated-zone water was observed with respect to depth or distance from disposal trenches. Tritium and dissolved organic carbon concentrations were, however, dependent on proximity to trenches. The primary reactions, both on-site and off-site, were carbonate and clay dissolution, cation exchange, and the oxidation of pyrite. The major difference between on-site and off-site inorganic water chemistry resulted from the removal of the Roxana Silt and the Radnor Till Member of the Glasford Formation from on-site. Off-site, the Roxana Silt contributed substantial quantities of sodium to solution from montmorillonite dissolution and associated cation-exchange reactions. The Radnor Till Member provided exchange surfaces for magnesium. Precipitation at the site had an ionic composition of calcium zinc sulfate and an average pH of 4.6. Within 0.3 meter of the land surface, infiltrating rainwater or snowmelt changed to an ionic composition of calcium sulfate off-site and calcium bicarbonate on-site and had an average pH of 7.9; below that depth, pH averaged 7.5 and the ionic composition generally was calcium magnesium bicarbonate. Alkalinity and specific conductance differed primarily according to composition of geologic materials. Tritium concentrations ranged from 0.2 (detection limit) to 1,380 nanocuries per liter. The

  19. Between visibility and surveillance

    DEFF Research Database (Denmark)

    Uldam, Julie

    As activists move from alternative media platforms to commercial social media platforms they face increasing challenges in protecting their online security and privacy. While government surveillance of activists is well-documented in both scholarly research and the media, corporate surveillance...... of activists remains under-researched. This presentation explores visibility as a prerequisite and an obstacle to political participation. The dual capacity of visibility in social media enables both surveillance and counter-surveillance by making not only the surveilled actor, but also the surveilling actor......’ surveillance of anti-capitalist activists in social media....

  20. The chemistry and isotopic composition of waters in the low-enthalpy geothermal system of Cimino-Vico Volcanic District, Italy

    Science.gov (United States)

    Battistel, Maria; Hurwitz, Shaul; Evans, William; Barbieri, Maurizio

    2017-01-01

    Geothermal energy exploration is based in part on interpretation of the chemistry, temperature, and discharge rate of thermal springs. Here we present the major element chemistry and the δD, δ18O, 87Sr/86Sr and δ11B isotopic ratio of groundwater from the low-enthalpy geothermal system near the city of Viterbo in the Cimino-Vico volcanic district of west-Central Italy. The geothermal system hosts many thermal springs and gas vents, but the resource is still unexploited. Water chemistry is controlled by mixing between low salinity,HCO3-rich fresh waters (<24.2°C) flowing in shallow volcanic rocks and SO4-rich thermal waters (25.3°C to 62.2°C) ascending from deep, high permeability Mesozoic limestones. The (equivalent) SO4/Cl (0.01–0.02), Na/Cl (2.82–5.83) and B/Cl ratios (0.02–0.38) of thermal waters differs from the ratios in other geothermal systems from Central Italy, probably implying a lack of hydraulic continuity across the region. The δ18O (−6.6‰ to −5.9‰) and δD (−40.60‰ to −36.30‰) isotopic composition of spring water suggest that the recharge area for the geothermal system is the summit region of Mount Cimino. The strontium isotope ratios (87Sr/86Sr) of thermal waters (0.70797–0.70805) are consistent with dissolution of the Mesozoic evaporite-carbonate units that constitute the reservoir, and the ratios of cold fresh waters mainly reflect shallow circulation through the volcanic cover and some minor admixture (<10%) of thermal water as well. The boron isotopic composition (δ11B) of fresh waters (−5.00 and 6.12‰) is similar to that of the volcanic cover, but the δ11B of thermal waters (−8.37‰ to −4.12‰) is a mismatch for the Mesozoic reservoir rocks and instead reflects dissolution of secondary boron minerals during fluid ascent through flysch units that overlie the reservoir. A slow and tortuous ascent enhances extraction of boron but also promotes conductive cooling, partially masking the heat present in the

  1. Chemistry Dashboard

    Science.gov (United States)

    The Chemistry Dashboard is part of a suite of dashboards developed by EPA to help evaluate the safety of chemicals. The Chemistry Dashboard provides access to a variety of information on over 700,000 chemicals currently in use.

  2. Combinatorial chemistry

    DEFF Research Database (Denmark)

    Nielsen, John

    1994-01-01

    An overview of combinatorial chemistry is presented. Combinatorial chemistry, sometimes referred to as `irrational drug design,' involves the generation of molecular diversity. The resulting chemical library is then screened for biologically active compounds.......An overview of combinatorial chemistry is presented. Combinatorial chemistry, sometimes referred to as `irrational drug design,' involves the generation of molecular diversity. The resulting chemical library is then screened for biologically active compounds....

  3. Collaboration Between Environmental Water Chemistry Students and Hazardous Waste Treatment Specialists on the University of Colorado-Boulder Campus

    Science.gov (United States)

    Dittrich, T. M.

    2012-12-01

    semester, the students conduct a bench-scale laboratory exercise where they study part of the treatment process. Several small start-up companies are testing components in the lab, which adds to the colaboration of the project.; Figure 1. Students in Environmental Water Chemistry lab conducting a titration.

  4. The First Water Analyses from Zvir Spring in Rijeka.A Contribution to the History of Chemistry in Rijeka - Part II

    Directory of Open Access Journals (Sweden)

    Alebic-Juretic, A.

    2008-03-01

    Full Text Available Although the territory of the Old Town of Rijeka is characterized by an abundance of water, the living conditions in this medieval town were threatening to public health. There was also a cemetery between the city walls, next to St. Mary's Church. Subsequent to the cholera outbreak in 1873, the municipal physician advised to abandon the use of water from the wells in possession of the cemetery. Therefore, the Municipality ordered the chemical analyses of water from Josef Koettstorfer, the professor of chemistry at the I&R. Naval Academy. During the spring of 1874, the firstchemical analyses were done on the waters from the springs Mustaccione and Sasso Bianco, and in the autumn the analyses were extended to springs Lešnjak and Zvir. The results from the latter analyses led to the conclusion that all waters were suitable as potable waters, although those fromLešnjak and Zvir were somewhat better. Waters from the Mustaccione spring were also good, and were already used for ship supply since 1873. Due to the rapid development of the harbour and the city itself, there was an urgent need to build up a new water supply system. Therefore, on 5th Oct 1886, the Municipality decided to order analyses of water from the Zvir spring. The analyses were carrier out from Dec 1886 to Nov 1887 by Prof. Koettstorfer. He used the most advanced methods at that time for chemical analyses, and therefore the results are comparable to current ones. Moreover, for the first time, the analyses of water also comprised bacteriological determination, as suggested by Dr. Koch on the World Hygienic Congress that was held at the end of 1885 in Berlin. The results of water analyses were the basis for the construction of the water supply system in the city that was exploited from 1894 to 1999.

  5. Removal of Aromatic Pollutant Surrogate from Water by Recyclable Magnetite-Activated Carbon Nanocomposite: An Experiment for General Chemistry

    Science.gov (United States)

    Furlan, Ping Y.; Melcer, Michael E.

    2014-01-01

    A general chemistry laboratory experiment using readily available chemicals is described to introduce college students to an exciting class of nanocomposite materials. In a one-step room temperature synthetic process, magnetite nanoparticles are embedded onto activated carbon matrix. The resultant nanocomposite has been shown to combine the…

  6. Transport of E. coli D21g with runoff water under different solution chemistry conditions and surface slopes

    Science.gov (United States)

    Tracer and indicator microbe runoff experiments were conducted to investigate the influence of solution chemistry on the transport, retention, and release of Escherichia coli D21g. Experiments were conducted in a chamber (2.25 m long, 0.15 m wide, and 0.16 m high) packed with ultrapure quartz sand (...

  7. Southwest Pacific deep water carbonate chemistry linked to high southern latitude climate and atmospheric CO2 during the Last Glacial Termination

    Science.gov (United States)

    Allen, Katherine A.; Sikes, Elisabeth L.; Hönisch, Bärbel; Elmore, Aurora C.; Guilderson, Thomas P.; Rosenthal, Yair; Anderson, Robert F.

    2015-08-01

    A greater amount of CO2 was stored in the deep sea during glacial periods, likely via greater efficiency of the biologic pump and increased uptake by a more alkaline ocean. Reconstructing past variations in seawater carbonate ion concentration (a major component of alkalinity) enables quantification of the relative roles of different oceanic CO2 storage mechanisms and also places constraints on the timing, magnitude, and location of subsequent deep ocean ventilation. Here, we present a record of deep-water inorganic carbon chemistry since the Last Glacial Maximum (LGM; ∼19-23 ka BP), derived from sediment core RR0503-83 raised from 1627 m in New Zealand's Bay of Plenty. The core site lies within the upper limit of southern-sourced Circumpolar Deep Water (CDW), just below the lower boundary of Antarctic Intermediate Water (AAIW). We reconstruct past changes in bottom water inorganic carbon chemistry from the trace element and stable isotopic composition of calcite shells of the epibenthic foraminifer Cibicidoides wuellerstorfi. A record of ΔCO32-(ΔCO32- = [COCO32-] in situ - [CO32-] saturation) derived from the foraminiferal boron to calcium ratio (B/Ca) provides evidence for greater ice-age storage of respired CO2 and reveals abrupt deglacial shifts in [CO32-] in situ of up to 30 μmol/kg (5 times larger than the difference between average LGM and Holocene values). The rapidity of these changes suggests the influence of changing water mass structure and atmospheric circulation in addition to a decrease in CO2 content of interior waters.

  8. Techniques for detecting effects of urban and rural land-use practices on stream-water chemistry in selected watersheds in Texas, Minnesota,and Illinois

    Science.gov (United States)

    Walker, J.F.

    1993-01-01

    Although considerable effort has been expended during the past two decades to control nonpoint-source contamination of streams and lakes in urban and rural watersheds, little has been published on the effectiveness of various management practices at the watershed scale. This report presents a discussion of several parametric and nonparametric statistical techniques for detecting changes in water-chemistry data. The need for reducing the influence of natural variability was recognized and accomplished through the use of regression equations. Traditional analyses have focused on fixed-frequency instantaneous concentration data; this report describes the use of storm load data as an alternative.

  9. How water chemistry determines the risk of metallic engineered nanoparticles in aquatic ecosystems: nAg and nZnO case study

    CSIR Research Space (South Africa)

    Thwala, Melusi

    2013-09-01

    Full Text Available stream_source_info Thwala1_2013.pdf.txt stream_content_type text/plain stream_size 4555 Content-Encoding UTF-8 stream_name Thwala1_2013.pdf.txt Content-Type text/plain; charset=UTF-8 How water chemistry determines..., University of Johannesburg, Johannesburg. 3DST/MINTEK Nanotechnology Innovation Centre, Advanced Materials Division, MINTEK, Johannesburg. 6TH SETAC AFRICA– 2-3 SEPTEMBER 2013 mthwala@csir.co.za reactivity solubility conductivity strength APPLICATIONS...

  10. Sonoma Persistent Surveillance System

    Energy Technology Data Exchange (ETDEWEB)

    Pennington, D M

    2006-03-24

    Sonoma offers the first cost-effective, broad-area, high-resolution, real-time motion imagery system for surveillance applications. Sonoma is unique in its ability to provide continuous, real-time video imagery of an area the size of a small city with resolutions sufficient to track 8,000 moving objects in the field of view. At higher resolutions and over smaller areas, Sonoma can even track the movement of individual people. The visual impact of the data available from Sonoma is already causing a paradigm shift in the architecture and operation of other surveillance systems. Sonoma is expected to cost just one-tenth the price of comparably sized sensor systems. Cameras mounted on an airborne platform constantly monitor an area, feeding data to the ground for real-time analysis. Sonoma was designed to provide real-time data for actionable intelligence in situations such as monitoring traffic, special events, border security, and harbors. If a Sonoma system had been available in the aftermath of the Katrina and Rita hurricanes, emergency responders would have had real-time information on roads, water levels, and traffic conditions, perhaps saving many lives.

  11. Questa baseline and pre-mining ground-water quality investigation. 20. Water chemistry of the Red River and selected seeps, tributaries, and precipitation, Taos County, New Mexico, 2000-2004

    Science.gov (United States)

    Verplanck, P.L.; McCleskey, R.B.; Nordstrom, D.K.

    2006-01-01

    As part of a multi-year project to infer the pre-mining ground-water quality at Molycorp's Questa mine site, surface-water samples of the Red River, some of its tributaries, seeps, and snow samples were collected for analysis of inorganic solutes and of water and sulfate stable isotopes in selected samples. The primary aim of this study was to document diel, storm event, and seasonal variations in water chemistry for the Red River and similar variations in water chemistry for Straight Creek, a natural analog site similar in topography, hydrology, and geology to the mine site for inferring pre-mining water-quality conditions. Red River water samples collected between 2000 and 2004 show that the largest variations in water chemistry occur during late summer rainstorms, often monsoonal in nature. Within hours, discharge of the Red River increased from 8 to 102 cubic feet per second and pH decreased from 7.80 to 4.83. The highest concentrations of metals (iron, aluminum, zinc, manganese) and sulfate also occur during such events. Low-pH and high-solute concentrations during rainstorm runoff are derived primarily from alteration 'scar' areas of naturally high mineralization combined with steep topography that exposes continually altered rock because erosion is too rapid for vegetative growth. The year 2002 was one of the driest on record, and Red River discharge reflected the low seasonal snow pack. No snowmelt peak appeared in the hydrograph record, and a late summer storm produced the highest flow for the year. Snowmelt was closer to normal during 2003 and demonstrated the dilution effect of snowmelt on water chemistry. Two diel sampling events were conducted for the Red River, one during low flow and the other during high flow, at two locations, at the Red River gaging station and just upstream from Molycorp's mill site. No discernible diel trends were observed except for dissolved zinc and manganese at the upstream site during low flow. Straight Creek drainage water

  12. The ecological effects of water level fluctuation and phosphate enrichment in mesotrophic peatlands are strongly mediated by soil chemistry

    NARCIS (Netherlands)

    Mettrop, I.S.; Rutte, M.D.; Kooijman, A.M.; Lamers, L.P.M.

    2015-01-01

    Since the re-establishment of a more natural water regime is considered by water management in wetlands with artificially stable water levels, the biogeochemical and ecological effects of water level fluctuation with different nutrient loads should be investigated. This is particularly important for

  13. Environmental control technology survey of selected US strip mining sites. Volume 2B. Alabama. Water quality impacts and overburden chemistry of Alabama study site

    Energy Technology Data Exchange (ETDEWEB)

    Henricks, J D; Bogner, J E; Olsen, R D; Schubert, J P; Sobek, A A; Johnson, D O

    1980-05-01

    As part of a program to examine the ability of existing control technologies to meet federal guidelines for the quality of aqueous effluents from coal mines, an intensive study of water, coal, and overburden chemistry was conducted at a surface coal mine in Alabama from May 1976 through July 1977. Sampling sites included the pit sump, a stream downgrade from the mine, the discharge from the water treatment facility, and a small stream outside the mine drainage. Water samples were collected every two weeks by Argonne subcontractors at the Alabama Geological Survey and analysed for the following parameters: specific conductance, pH, temperature, acidity, bicarbonate, carbonate, chloride, total dissolved solids, suspended solids, sulfate, and 20 metals. Analysis of the coal and overburden shows that no potential acid problem exists at this mine. Water quality is good in both streams sampled, and high levels of dissolved elements are found only in water collected from the pit sump. The mine effluent is in compliance with Office of Surface Mining water quality standards.

  14. Chemistry Technology

    Data.gov (United States)

    Federal Laboratory Consortium — Chemistry technology experts at NCATS engage in a variety of innovative translational research activities, including:Design of bioactive small molecules.Development...

  15. Synthesis of water-compatible surface-imprinted polymer via click chemistry and RAFT precipitation polymerization for highly selective and sensitive electrochemical assay of fenitrothion.

    Science.gov (United States)

    Zhao, Lijuan; Zhao, Faqiong; Zeng, Baizhao

    2014-12-15

    A novel water-compatible fenitrothion imprinted polymer was prepared on Au nanoparticles (AuNPs) by click chemistry and reversible addition-fragmentation chain transfer (RAFT) precipitation polymerization (RAFTPP). The RAFT chain-transfer agent was synthesized on the surface of AuNPs using click chemistry, then an imprinted polymer with hydrophilic polymer brushes was prepared on the RAFT chain-transfer agent modified AuNPs by RAFTPP, mediated by hydrophilic polyethylene glycol macromolecular cochain-transfer agent. The obtained molecularly imprinted material showed improved accessibility to fenitrothion and recognition property in water medium. When the material was immobilized on an ionic liquid functionalized graphene coated glassy carbon electrode for the electrochemical determination of fenitrothion, the resulting electrochemical sensor presented linear response in the range of 0.01-5 μM, with a sensitivity of 6.1 μA/μM mm(2). The low limit of detection was 8 nM (S/N=3). The sensor was successfully applied to the determination of real samples and the recovery for standard added was 95-108%. Copyright © 2014 Elsevier B.V. All rights reserved.

  16. Assessment of stream water chemistry and impact of geothermal fluid in the up-Buyuk Menderes Basin, Turkey.

    Science.gov (United States)

    Davraz, Aysen; Aksever, Fatma; Afsin, Mustafa

    2017-12-01

    The discharge of geothermal fluid into the natural water environment may lead to serious damages. In this study, the impact of geothermal waste water on surface water has been investigated in the up-Buyuk Menderes River, Turkey. Thermal return water from district heating and from thermal bath in the Sandıklı region were the most important source of major solutes and trace elements to the up-Buyuk Menderes River and tributaries. The thermal contribution causes a drastic increase in Na, SO4 ions, EC, and temperature of surface waters. The concentrations of As, Al, B, Fe, Cr, Li, S, P, Pb, U, Mn, and Zn are increasing dramatically downstream of thermal water inputs in the Kufi Creek tributary. In addition to natural thermal water inputs, water quality was impacted by anthropogenic trace and major element inputs from surface waters. The increased of some trace elements (Al, As, B, Cu, Cd, Fe, Mn, P, U) in surface water are related to anthropogenic activities such as agricultural activities, sewage effluents, and stockyards in the study area. Additionally, surface water quality of the up-Buyuk Menderes River and tributaries was evaluated according to standards given by the Environmental Protection Agency of both Turkey and USA. Our study demonstrates the influence of thermal water inputs on water quality of surface waters.

  17. Journal of Applied Chemistry and Agricultural Research: Submissions

    African Journals Online (AJOL)

    ... Applied Chemistry. Applied Chemistry manuscripts should be restricted to corrosion of materials, environmental chemistry and water quality (pollution studies), phyisco-chemical properties of naturally occurring products, colloid chemistry, nutritional chemistry and metallurgy. Articles must be original and written in English.

  18. Hydrogeology, Water Chemistry, and Factors Affecting the Transport of Contaminants in the Zone of Contribution of a Public-Supply Well in Modesto, Eastern San Joaquin Valley, California

    Science.gov (United States)

    Jurgens, Bryant C.; Burow, Karen R.; Dalgish, Barbara A.; Shelton, Jennifer L.

    2008-01-01

    Ground-water chemistry in the zone of contribution of a public-supply well in Modesto, California, was studied by the U.S. Geological Survey National Water Quality Assessment (NAWQA) Program's topical team for Transport of Anthropogenic and Natural Contaminants (TANC) to supply wells. Twenty-three monitoring wells were installed in Modesto to record baseline hydraulic information and to collect water-quality samples. The monitoring wells were divided into four categories that represent the chemistry of different depths and volumes of the aquifer: (1) water-table wells were screened between 8.5 and 11.7 m (meter) (28 and 38.5 ft [foot]) below land surface (bls) and were within 5 m (16 ft) of the water table; (2) shallow wells were screened between 29 and 35 m (95 and 115 ft) bls; (3) intermediate wells were screened between 50.6 and 65.5 m (166 and 215 ft) bls; and (4) deep wells are screened between 100 to 106 m (328 and 348 ft) bls. Inorganic, organic, isotope, and age-dating tracers were used to characterize the geochemical conditions in the aquifer and understand the mechanisms of mobilization and movement of selected constituents from source areas to a public-supply well. The ground-water system within the study area has been significantly altered by human activities. Water levels in monitoring wells indicated that horizontal movement of ground water was generally from the agricultural areas in the northeast towards a regional water-level depression within the city in the southwest. However, intensive pumping and irrigation recharge in the study area has caused large quantities of ground water to move vertically downward within the regional and local flow systems. Analysis of age tracers indicated that ground-water age varied from recent recharge at the water table to more than 1,000 years in the deep part of the aquifer. The mean age of shallow ground water was determined to be between 30 and 40 years. Intermediate ground water was determined to be a mixture

  19. Current organic chemistry

    National Research Council Canada - National Science Library

    1997-01-01

    Provides in depth reviews on current progress in the fields of asymmetric synthesis, organometallic chemistry, bioorganic chemistry, heterocyclic chemistry, natural product chemistry, and analytical...

  20. Characterization of the water chemistry, sediment (13)C and (18)O compositions of Kolleru Lake-a Ramsar wetland in Andhra Pradesh, India.

    Science.gov (United States)

    Das Sharma, Subrata; Sujatha, D

    2016-07-01

    The chemistry of surface water sampled at different locations of the Kolleru Lake in Andhra Pradesh (India) show heterogeneous variability. The concentrations of dissolved sodium and chloride ions, total dissolved solids (TDS) together with high conductivity documented in water samples are indicative of mixing of saline seawater. This interpretation is further corroborated by enriched δ(18)O compositions of the carbonate fraction of the surface sediments collected at the same locations (as that of water) of the lake, and fairly good positive correlations of δ(18)O -Na(+) and δ(18)O-TDS. The saline water intrusion into the lake appears to be resulted due to its near stagnant to dry condition with reduced inflow and outflow. Such dry condition facilitated seawater intrusion into the lake due to several reasons: (i) proximity of lake to the sea (~35 km), (ii) overexploitation of fresh groundwater for agriculture as well as livestock farming, and (iii) incursion of tidal seawater (high sea waves) through Upputeru River, which is directly linked to the sea. We also document highly heterogeneous distribution of certain potentially toxic metal ions like chromium, copper, manganese, and zinc in the lake waters. Indiscriminate disposal of domestic and industrial effluents around the lake appears to be responsible for the presence of potentially toxic heavy metals. Based on these results, we finally suggest some measures for environmental rehabilitation of the lake and its surroundings.

  1. Surveillance and Communication

    DEFF Research Database (Denmark)

    Bøge, Ask Risom; Albrechtslund, Anders; Lauritsen, Peter

    2017-01-01

    eyes of cameras are but one of many important aspects of the surveillance society. In particular, surveillance has become intrinsic to our digitally mediated communication. Many are constantly engaged in forms of social surveillance as they observe what friends, family, celebrities, love interests...... represent and define us in lieu of our embodied selves. It is thus vital for students and scholars in the field of communication to address surveillance issues. This article takes up the task of providing an overview of the most relevant work on surveillance for the field of communication. The article...... to surveillance studies’ undertakings and politics. Third, the article presents the reader with core surveillance theories and their sources of inspiration. It points to the panopticon, which has been a dominant but also controversial concept, but mostly the bibliography suggests post-panoptic theories, which...

  2. Influence of surface chemistry of carbon materials on their interactions with inorganic nitrogen contaminants in soil and water.

    Science.gov (United States)

    Sumaraj; Padhye, Lokesh P

    2017-10-01

    Inorganic nitrogen contaminants (INC) (NH 4 + , NO 3 - , NO 2 - , NH 3 , NO, NO 2 , and N 2 O) pose a growing risk to the environment, and their remediation methods are highly sought after. Application of carbon materials (CM), such as biochar and activated carbon, to remediate INC from agricultural fields and wastewater treatment plants has gained a significant interest since past few years. Understanding the role of surface chemistry of CM in adsorption of various INC is highly critical to increase adsorption efficiency as well as to assess the long term impact of using these highly recalcitrant CM for remediation of INC. Critical reviews of adsorption studies related to INC have revealed that carbon surface chemistry (surface functional groups, pH, Eh, elemental composition, and mineral content) has significant influence on adsorption of INC. Compared to basic functional groups, oxygen containing surface functional groups have been found to be more influential for adsorption of INC. However, basic sites on carbon materials still play an important role in chemisorption of anionic INC. Apart from surface functional groups, pH, Eh and pH zpc of CM and elemental and mineral composition of its surface are important properties capable of altering INC interactions with CM. This review summarizes our current understanding of INC interactions with CM's surface through the known chemisorption mechanisms: electrostatic interaction, hydrogen bonding, electron donor-acceptor mechanism, hydrophobic and hydrophilic interaction, chemisorption aided by minerals, and interactions influenced by pH and elemental composition. Change in surface chemistry of CM in soil during aging is also discussed. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. How the right chemistry in the FGD unit helps to improve the performance in the waste water treatment plant

    Energy Technology Data Exchange (ETDEWEB)

    Vredenbregt, Leo [DNV KEMA Energy Sustainability, Arnhem (Netherlands)

    2012-07-01

    The chemistry in the wet flue gas desulphurisation (FGD) unit is complex and far from constant, depending on fuel composition and flue gas conditions. Trace elements that exist in several oxidation states and which are of environmental importance are As, Cr, Hg, Mn, Se, Sb and Tl. From results with 'jar tests', in which the wastewater treatment plant (WWTP) is simulated, it becomes clear that the removal in the WWTP cannot be optimal for all elements at the same time at certain ORP conditions in the FGD. (orig.)

  4. Conceptual evaluation of population health surveillance programs: method and example.

    Science.gov (United States)

    El Allaki, Farouk; Bigras-Poulin, Michel; Ravel, André

    2013-03-01

    Veterinary and public health surveillance programs can be evaluated to assess and improve the planning, implementation and effectiveness of these programs. Guidelines, protocols and methods have been developed for such evaluation. In general, they focus on a limited set of attributes (e.g., sensitivity and simplicity), that are assessed quantitatively whenever possible, otherwise qualitatively. Despite efforts at standardization, replication by different evaluators is difficult, making evaluation outcomes open to interpretation. This ultimately limits the usefulness of surveillance evaluations. At the same time, the growing demand to prove freedom from disease or pathogen, and the Sanitary and Phytosanitary Agreement and the International Health Regulations require stronger surveillance programs. We developed a method for evaluating veterinary and public health surveillance programs that is detailed, structured, transparent and based on surveillance concepts that are part of all types of surveillance programs. The proposed conceptual evaluation method comprises four steps: (1) text analysis, (2) extraction of the surveillance conceptual model, (3) comparison of the extracted surveillance conceptual model to a theoretical standard, and (4) validation interview with a surveillance program designer. This conceptual evaluation method was applied in 2005 to C-EnterNet, a new Canadian zoonotic disease surveillance program that encompasses laboratory based surveillance of enteric diseases in humans and active surveillance of the pathogens in food, water, and livestock. The theoretical standard used for evaluating C-EnterNet was a relevant existing structure called the "Population Health Surveillance Theory". Five out of 152 surveillance concepts were absent in the design of C-EnterNet. However, all of the surveillance concept relationships found in C-EnterNet were valid. The proposed method can be used to improve the design and documentation of surveillance programs. It

  5. Chemistry and origin of deep ground water in crystalline rocks; Kemi och genes av djupa grundvatten i kristallint berg

    Energy Technology Data Exchange (ETDEWEB)

    Lagerblad, B. [Swedish Cement and Concrete Research Inst., Stockholm (Sweden)

    1995-11-01

    This report discusses the interactions between water and crystalline rocks and its consequences for the chemical composition of the water. It also treats how flows of different types of water are modified by the rock, and the possible consequences for the ground water near a nuclear waste repository. The focus of the work is the changes in composition that ground water gets at deep levels in the rock. Data from Finnsjoen and Aespoe in Sweden show higher salinity in deep rock, which has been interpreted as a result of marine inflow of water during glaciation. Data from other, deeper boreholes in Finland, Canada, Russia, England and Sweden show that the increasing salinity is a rule and very high at great depths, higher than marine water can produce. Therefore, the deep waters from Finnsjoen and Aespoe are probably very old, and the high salinity a result from geological processes. Differing cation and isotopic composition than seawater also indicate geologic water. Differing theories on the origin of the ground water should be regarded in the safety analysis for a repository. 36 refs, 3 figs, 1 tab.

  6. Evaluation of groundwater chemistry and its impact on drinking and irrigation water quality in the eastern part of the Central Arabian graben and trough system, Saudi Arabia

    Science.gov (United States)

    Zaidi, Faisal K.; Mogren, Saad; Mukhopadhyay, Manoj; Ibrahim, Elkhedr

    2016-08-01

    The present study deals with the assessment of groundwater with respect to the main hydrological processes controlling its chemistry and its subsequent impact on groundwater quality for drinking and irrigation purposes in the eastern part of the Central Arabian graben and trough system. Groundwater samples were collected from 73 bore wells tapping the Cretaceous Biyadh and Wasia sandstone aquifers. The main groundwater facies in the area belong to the mixed Casbnd Mgsbnd SO4/Cl type and the SO4sbnd Cl type. Prolonged rock water interaction has resulted in high TDS (average of 2131 mg/l) and high EC (average of 2725 μS/cm) of the groundwater. The average nitrate (56.38 mg/l) value in the area is higher than the WHO prescribed limits of 50 mg/l in drinking water and is attributed to agricultural activities. The Drinking Water Quality Index (DWQI) shows that 33% of the water samples fall within the excellent to good category whereas the remaining samples fall in the poor to unsuitable for drinking category. In terms of Sodium Adsorption Ratio (SAR), Sodium percentage (Na %) and Residual Sodium Carbonate (RSC) the groundwater is suitable for irrigation however the high salinity values can adversely affect the plant physiology.

  7. In-Package Chemistry Abstraction

    Energy Technology Data Exchange (ETDEWEB)

    P.S. Domski

    2003-07-21

    The work associated with the development of this model report was performed in accordance with the requirements established in ''Technical Work Plan for Waste Form Degradation Modeling, Testing, and Analyses in Support of SR and LA'' (BSC 2002a). The in-package chemistry model and in-package chemistry model abstraction are developed to predict the bulk chemistry inside of a failed waste package and to provide simplified expressions of that chemistry. The purpose of this work is to provide the abstraction model to the Performance Assessment Project and the Waste Form Department for development of geochemical models of the waste package interior. The scope of this model report is to describe the development and validation of the in-package chemistry model and in-package chemistry model abstraction. The in-package chemistry model will consider chemical interactions of water with the waste package materials and the waste form for commercial spent nuclear fuel (CSNF) and codisposed high-level waste glass (HLWG) and N Reactor spent fuel (CDNR). The in-package chemistry model includes two sub-models, the first a water vapor condensation (WVC) model, where water enters a waste package as vapor and forms a film on the waste package components with subsequent film reactions with the waste package materials and waste form--this is a no-flow model, the reacted fluids do not exit the waste package via advection. The second sub-model of the in-package chemistry model is the seepage dripping model (SDM), where water, water that may have seeped into the repository from the surrounding rock, enters a failed waste package and reacts with the waste package components and waste form, and then exits the waste package with no accumulation of reacted water in the waste package. Both of the submodels of the in-package chemistry model are film models in contrast to past in-package chemistry models where all of the waste package pore space was filled with water. The

  8. Quantum chemistry

    CERN Document Server

    Lowe, John P

    1993-01-01

    Praised for its appealing writing style and clear pedagogy, Lowe's Quantum Chemistry is now available in its Second Edition as a text for senior undergraduate- and graduate-level chemistry students. The book assumes little mathematical or physical sophistication and emphasizes an understanding of the techniques and results of quantum chemistry, thus enabling students to comprehend much of the current chemical literature in which quantum chemical methods or concepts are used as tools. The book begins with a six-chapter introduction of standard one-dimensional systems, the hydrogen atom,

  9. Influence of drainage status on soil and water chemistry, litter decomposition and soil respiration in central Amazonian forests on sandy soils

    Directory of Open Access Journals (Sweden)

    Antônio Ocimar Manzi

    2011-04-01

    Full Text Available Central Amazonian rainforest landscape supports a mosaic of tall terra firme rainforest and ecotone campinarana, riparian and campina forests, reflecting topography-induced variations in soil, nutrient and drainage conditions. Spatial and temporal variations in litter decomposition, soil and groundwater chemistry and soil CO2 respiration were studied in forests on sandy soils, whereas drought sensitivity of poorly-drained valley soils was investigated in an artificial drainage experiment. Slightly changes in litter decomposition or water chemistry were observed as a consequence of artificial drainage. Riparian plots did experience higher litter decomposition rates than campina forest. In response to a permanent lowering of the groundwater level from 0.1 m to 0.3 m depth in the drainage plot, topsoil carbon and nitrogen contents decreased substantially. Soil CO2 respiration decreased from 3.7±0.6 µmol m-2 s-1 before drainage to 2.5±0.2 and 0.8±0.1 µmol m-2 s-1 eight and 11 months after drainage, respectively. Soil respiration in the control plot remained constant at 3.7±0.6 µmol m-2 s-1. The above suggests that more frequent droughts may affect topsoil carbon and nitrogen content and soil respiration rates in the riparian ecosystem, and may induce a transition to less diverse campinarana or short-statured campina forest that covers areas with strongly-leached sandy soil.

  10. Determination of concentration of radon, volatile organic compounds (VOC) and water chemistry in springs near to Popocatepetl volcano; Determinacion de la concentracion de radon, VOCs y Quimica del agua en manantiales cercanos al volcan Popocatepetl

    Energy Technology Data Exchange (ETDEWEB)

    Pena, P.; Segovia, N.; Lopez M, B.E.; Cisniega, G. [ININ, A.P. 18-1027, 11801 Mexico D.F. (Mexico); Valdes, C.; Armienta, M.A.; Mena, M. [Instituto de Geofisica, UNAM, 04510 Mexico D.F. (Mexico)

    2004-07-01

    Popocatepetl volcano is a high-risk active volcano in Central Mexico where the highest population density in the country is settled. Radon in the soil and groundwater together with water chemistry from samples of nearby springs is analysed as a function of the 2002-2003 volcanic activity. Soil radon indicated fluctuations related both the meteorological parameters and sporadic explosive events. Groundwater radon showed essentially differences in concentration due to the specific characteristics of the studied springs. Water chemistry showed stability along the monitoring period indicating also differences between springs. No anthropogenic pollution from volatile organic compounds was observed. (Author)

  11. Epidemiological surveillance, virulence and public health ...

    African Journals Online (AJOL)

    gulab pandove

    Epidemiological surveillance of drinking water from Punjab, India reported occurrence of Listeria spp. in 58.67% of Municipal Corporation (MC), 51.38% ... wage, water, feedstuffs, milk, cheese, meconium, feces and soil (Kirkan et al., 2006). ... sea, vomiting and abdominal pain in healthy adults. (Lunden et al., 2004). Listeria ...

  12. Water Chemistry Impacts on Arsenic Mobilization from Arsenopyrite Dissolution and Secondary Mineral Precipitation: Implications for Managed Aquifer Recharge

    Science.gov (United States)

    Managed Aquifer Recharge (MAR) is one water reuse technique with the potential to meet growing water demands. However, MAR sites have encountered arsenic remobilization resulting from recharge operations. To combat this challenge, it is important to identify the mechanism of arse...

  13. Shallow groundwater and soil chemistry response to 3 years of subsurface drip irrigation using coalbed-methane-produced water

    Science.gov (United States)

    Bern, C. R.; Boehlke, A. R.; Engle, M. A.; Geboy, N. J.; Schroeder, K. T.; Zupancic, J. W.

    2013-12-01

    Disposal of produced waters, pumped to the surface as part of coalbed methane (CBM) development, is a significant environmental issue in the Wyoming portion of the Powder River Basin, USA. High sodium adsorption ratios (SAR) of the waters could degrade agricultural land, especially if directly applied to the soil surface. One method of disposing of CBM water, while deriving beneficial use, is subsurface drip irrigation (SDI), where acidified CBM waters are applied to alfalfa fields year-round via tubing buried 0.92 m deep. Effects of the method were studied on an alluvial terrace with a relatively shallow depth to water table (˜3 m). Excess irrigation water caused the water table to rise, even temporarily reaching the depth of drip tubing. The rise corresponded to increased salinity in some monitoring wells. Three factors appeared to drive increased groundwater salinity: (1) CBM solutes, concentrated by evapotranspiration; (2) gypsum dissolution, apparently enhanced by cation exchange; and (3) dissolution of native Na-Mg-SO4 salts more soluble than gypsum. Irrigation with high SAR (˜24) water has increased soil saturated paste SAR up to 15 near the drip tubing. Importantly though, little change in SAR has occurred at the surface.

  14. Water-level fluctuations influence sediment porewater chemistry and methylmercury production in a flood-control reservoir.

    Science.gov (United States)

    Reservoirs typically have elevated fish mercury (Hg) levels compared to natural lakes and rivers. A unique feature of reservoirs is water-level management which can result in sediment exposure to the air. The objective of this study is to identify how reservoir water-level fluct...

  15. HD 209458b in new light: evidence of nitrogen chemistry, patchy clouds and sub-solar water

    Science.gov (United States)

    MacDonald, Ryan J.; Madhusudhan, Nikku

    2017-08-01

    Interpretations of exoplanetary transmission spectra have been undermined by apparent obscuration due to clouds/hazes. Debate rages on whether weak H2O features seen in exoplanet spectra are due to clouds or inherently depleted oxygen. Assertions of solar H2O abundances have relied on making a priori model assumptions, for example, chemical/radiative equilibrium. In this work, we attempt to address this problem with a new retrieval paradigm for transmission spectra. We introduce poseidon, a two-dimensional atmospheric retrieval algorithm including generalized inhomogeneous clouds. We demonstrate that this prescription allows one to break vital degeneracies between clouds and prominent molecular abundances. We apply poseidon to the best transmission spectrum presently available, for the hot Jupiter HD 209458b, uncovering new insights into its atmosphere at the day-night terminator. We extensively explore the parameter space with an unprecedented 108 models, spanning the continuum from fully cloudy to cloud-free atmospheres, in a fully Bayesian retrieval framework. We report the first detection of nitrogen chemistry (NH3 and/or HCN) in an exoplanet atmosphere at 3.7-7.7σ confidence, non-uniform cloud coverage at 4.5-5.4σ, high-altitude hazes at >3σ and sub-solar H2O at ≳3-5σ, depending on the assumed cloud distribution. We detect NH3 at 3.3σ, and 4.9σ for fully cloudy and cloud-free scenarios, respectively. For the model with the highest Bayesian evidence, we constrain H2O at 5-15 ppm (0.01-0.03) × solar and NH3 at 0.01-2.7 ppm, strongly suggesting disequilibrium chemistry and cautioning against equilibrium assumptions. Our results herald a new promise for retrieving cloudy atmospheres using high-precision Hubble Space Telescope and James Webb Space Telescope spectra.

  16. Materials Chemistry

    CERN Document Server

    Fahlman, Bradley D

    2011-01-01

    The 2nd edition of Materials Chemistry builds on the strengths that were recognized by a 2008 Textbook Excellence Award from the Text and Academic Authors Association (TAA). Materials Chemistry addresses inorganic-, organic-, and nano-based materials from a structure vs. property treatment, providing a suitable breadth and depth coverage of the rapidly evolving materials field. The 2nd edition continues to offer innovative coverage and practical perspective throughout. After briefly defining materials chemistry and its history, seven chapters discuss solid-state chemistry, metals, semiconducting materials, organic "soft" materials, nanomaterials, and materials characterization. All chapters have been thoroughly updated and expanded with, for example, new sections on ‘soft lithographic’ patterning, ‘click chemistry’ polymerization, nanotoxicity, graphene, as well as many biomaterials applications. The polymer and ‘soft’ materials chapter represents the largest expansion for the 2nd edition. Each ch...

  17. Nuclear Chemistry.

    Science.gov (United States)

    Chemical and Engineering News, 1979

    1979-01-01

    Provides a brief review of the latest developments in nuclear chemistry. Nuclear research today is directed toward increased activity in radiopharmaceuticals and formation of new isotopes by high-energy, heavy-ion collisions. (Author/BB)

  18. Green Chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Collison, Melanie

    2011-05-15

    Green chemistry is the science of chemistry used in a way that will not use or create hazardous substances. Dr. Rui Resendes is working in this field at GreenCentre Canada, an offshoot of PARTEQ Innovations in Kingston, Ontario. GreenCentre's preliminary findings suggest their licensed product {sup S}witchable Solutions{sup ,} featuring 3 classes of solvents and a surfactant, may be useful in bitumen oil sands extraction.

  19. Evaluating physical habitat and water chemistry data from statewide stream monitoring programs to establish least-impacted conditions in Washington State

    Science.gov (United States)

    Wilmoth, Siri K.; Irvine, Kathryn M.; Larson, Chad

    2015-01-01

    Various GIS-generated land-use predictor variables, physical habitat metrics, and water chemistry variables from 75 reference streams and 351 randomly sampled sites throughout Washington State were evaluated for effectiveness at discriminating reference from random sites within level III ecoregions. A combination of multivariate clustering and ordination techniques were used. We describe average observed conditions for a subset of predictor variables as well as proposing statistical criteria for establishing reference conditions for stream habitat in Washington. Using these criteria, we determined whether any of the random sites met expectations for reference condition and whether any of the established reference sites failed to meet expectations for reference condition. Establishing these criteria will set a benchmark from which future data will be compared.

  20. The influence of operational and water chemistry parameters on the deposits of corrosion products on fuel assemblies at nuclear power plants with VVER reactors

    Science.gov (United States)

    Kritskii, V. G.; Berezina, I. G.; Rodionov, Yu. A.; Gavrilov, A. V.

    2011-07-01

    The phenomenon involving a growth of pressure drop in the reactor core and redistribution of deposits in the reactor core and primary coolant circuit of a nuclear power station equipped with VVER-440 reactors is considered. A model is developed, the physicochemical foundation of which is based on the dependence of corrosion product transfer on the temperature and pH t value of coolant and on the correlation between the formation rate of corrosion products (Fe) (after subjecting the steam generators to decontamination) and rate with which they are removed from the circuit. The purpose of the simulation carried on the model is to predict the growth of pressure drop on the basis of field data obtained from nuclear power installations and correct the water chemistry (by adjusting the concentrations of KOH, H2, and NH3) so as to keep the pressure drop in the reactor at a stable level.

  1. Effect of surface chemistry, solution pH, and ionic strength on the removal of herbicides diuron and amitrole from water by an activated carbon fiber.

    Science.gov (United States)

    Fontecha-Cámara, M A; López-Ramón, M V; Alvarez-Merino, M A; Moreno-Castilla, C

    2007-01-30

    A study was conducted on the effects of carbon surface chemistry, solution pH, and ionic strength on the removal of diuron and amitrole from aqueous solutions by adsorption on an as-received and oxidized activated carbon fiber. Results obtained were explained by the surface characteristics of the adsorbents and the characteristics of the herbicide molecules. Under the experimental conditions used, diuron uptake was much higher than that of amitrole, despite its larger molecular dimensions, due to the lesser water solubility, greater hydrophobicity, and larger dipolar moment of diuron compared with amitrole. Uptake variations associated with differences in carbon surface oxidation, solution pH, and ionic strength were explained by corresponding changes in electrostatic, hydrophobic, and van der Waals interactions.

  2. Journal of Applied Chemistry and Agricultural Research

    African Journals Online (AJOL)

    JACAR is a learned journal devoted to the publication of high quality articles in all areas of Agricultural Sciences and Applied Chemistry. Applied Chemistry manuscripts should be restricted to corrosion of materials, environmental chemistry and water quality (pollution studies), physico-chemical properties of naturally ...

  3. Handbook of surveillance technologies

    CERN Document Server

    Petersen, JK

    2012-01-01

    From officially sanctioned, high-tech operations to budget spy cameras and cell phone video, this updated and expanded edition of a bestselling handbook reflects the rapid and significant growth of the surveillance industry. The Handbook of Surveillance Technologies, Third Edition is the only comprehensive work to chronicle the background and current applications of the full-range of surveillance technologies--offering the latest in surveillance and privacy issues.Cutting-Edge--updates its bestselling predecessor with discussions on social media, GPS circuits in cell phones and PDAs, new GIS s

  4. Surveillance as cultural practice.

    Science.gov (United States)

    Monahan, Torin

    2011-01-01

    This special section of The Sociological Quarterly explores research on “surveillance as cultural practice,” which indicates an orientation to surveillance that views it as embedded within, brought about by, and generative of social practices in specific cultural contexts. Such an approach is more likely to include elements of popular culture, media, art, and narrative; it is also more likely to try to comprehend people's engagement with surveillance on their own terms, stressing the production of emic over etic forms of knowledge. This introduction sketches some key developments in this area and discusses their implications for the field of “surveillance studies” as a whole.

  5. Groundwater's significance to changing hydrology, water chemistry, and biological communities of a floodplain ecosystem, Everglades, South Florida, USA

    Science.gov (United States)

    Harvey, J.W.; McCormick, P.V.

    2009-01-01

    The Everglades (Florida, USA) is one of the world's larger subtropical peatlands with biological communities adapted to waters low in total dissolved solids and nutrients. Detecting how the pre-drainage hydrological system has been altered is crucial to preserving its functional attributes. However, reliable tools for hindcasting historic conditions in the Everglades are limited. A recent synthesis demonstrates that the proportion of surface-water inflows has increased relative to precipitation, accounting for 33% of total inputs compared with 18% historically. The largest new source of water is canal drainage from areas of former wetlands converted to agriculture. Interactions between groundwater and surface water have also increased, due to increasing vertical hydraulic gradients resulting from topographic and water-level alterations on the otherwise extremely flat landscape. Environmental solute tracer data were used to determine groundwater's changing role, from a freshwater storage reservoir that sustained the Everglades ecosystem during dry periods to a reservoir of increasingly degraded water quality. Although some of this degradation is attributable to increased discharge of deep saline groundwater, other mineral sources such as fertilizer additives and peat oxidation have made a greater contribution to water-quality changes that are altering mineral-sensitive biological communities. ?? Springer-Verlag 2008.

  6. Cycling of mercury across the sediment-water interface in seepage lakes: Chapter 13, Advances in Chemistry

    Science.gov (United States)

    Hurley, James P.; Krabbenhoft, David P.; Babiarz, Christopher L.; Andren, Anders

    1994-01-01

    The magnitude and direction of Hg fluxes across the sediment—water interface were estimated by groundwater, dry bulk sediment, sediment pore water, sediment trap, and water-column analyses in two northern Wisconsin seepage lakes. Little Rock Lake (Treatment Basin) received no groundwater discharge during the study period (1988—1990), and Follette Lake received continuous groundwater discharge. In Little Rock Lake, settling of particulate matter accounted for the major Hg delivery mechanism to the sediment—water interface. Upward diffusion of Hg from sediment pore waters below 2—4-cm sediment depth was apparently a minor source during summer stratification. Time-series comparisons suggested that the observed buildup of Hg in the hypolimnion of Little Rock Lake was attributable to dissolution and diffusion of Hg from recently fallen particulate matter close to the sediment—water interface. Groundwater inflow represented an important source of new Hg, and groundwater outflow accounted for significant removal of Hg from Pallette Lake. Equilibrium speciation calculations revealed that association of Hg with organic matter may control solubility in well-oxygenated waters, whereas in anoxic environments sulfur (polysulfide and bisulfide) complexation governs dissolved total Hg levels.

  7. The influence of modified water chemistries on metal oxide films, activity build-up and stress corrosion cracking of structural materials in nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Maekelae, K.; Laitinen, T.; Bojinov, M. [VTT Manufacturing Technology, Espoo (Finland)

    1999-03-01

    The primary coolant oxidises the surfaces of construction materials in nuclear power plants. The properties of the oxide films influence significantly the extent of incorporation of actuated corrosion products into the primary circuit surfaces, which may cause additional occupational doses for the maintenance personnel. The physical and chemical properties of the oxide films play also an important role in different forms of corrosion observed in power plants. This report gives a short overview of the factors influencing activity build-up and corrosion phenomena in nuclear power plants. Furthermore, the most recent modifications in the water chemistry to decrease these risks are discussed. A special focus is put on zinc water chemistry, and a preliminary discussion on the mechanism via which zinc influences activity build-up is presented. Even though the exact mechanisms by which zinc acts are not yet known, it is assumed that Zn may block the diffusion paths within the oxide film. This reduces ion transport through the oxide films leading to a reduced rate of oxide growth. Simultaneously the number of available adsorption sites for {sup 60}Co is also reduced. The current models for stress corrosion cracking assume that the anodic and the respective cathodic reactions contributing to crack growth occur partly on or in the oxide films. The rates of these reactions may control the crack propagation rate and therefore, the properties of the oxide films play a crucial role in determining the susceptibility of the material to stress corrosion cracking. Finally, attention is paid also on the novel techniques which can be used to mitigate the susceptibility of construction materials to stress corrosion cracking. (orig.) 127 refs.

  8. Environmental surveillance master sampling schedule

    Energy Technology Data Exchange (ETDEWEB)

    Bisping, L.E.

    1997-01-01

    Environmental surveillance of the Hanford Site and surrounding areas is conducted by the Pacific Northwest National Laboratory (PNNL)(a) for the US Department of Energy (DOE). This document contains the planned 1997 schedules for routine collection of samples for the Surface Environmental Surveillance Project (SESP) and Drinking Water Monitoring Project. In addition, Section 3.0, Biota, also reflects a rotating collection schedule identifying the year a specific sample is scheduled for collection. The purpose of these monitoring projects is to evaluate levels of radioactive and nonradioactive pollutants in the Hanford environs, as required in DOE Order 5400.1, General Environmental Protection Program, and DOE Order 5400.5, Radiation Protection of the Public and the Environment. The sampling methods will be the same as those described in the Environmental Monitoring Plan, US Department of Energy, Richland Operations Office, DOE/RL91-50, Rev. 1, US Department of Energy, Richland, Washington.

  9. Photocatalytic Treatment of Desalination Concentrate Using Optical Fibers Coated With Nanostructured Thin Films: Impact of Water Chemistry and Seasonal Climate Variations.

    Science.gov (United States)

    Lin, Lu; Wang, Huiyao; Luo, Hongmei; Xu, Pei

    2016-05-01

    Treatment of desalination concentrate can reduce concentrate volume for disposal, increase water recovery and convert waste to resource. However, concentrate treatment is costly and energy intensive due to high concentrations of salt and recalcitrant organic matter in concentrate. Photocatalytic oxidation provides a novel energy neutral technology for concentrate treatment by degrading organic contaminants. Polymer-assisted hydrothermal deposition method was used to synthesize innovative pure and Fe-doped TiO2 mixed-phase nanocomposite thin films on side-glowing optical fibers (SOFs). The properties of the photocatalysts-coated SOF were characterized by surface morphology, nanostructure, crystallite size and phase and zeta potential. Photodegradation efficiency and durability of the photocatalysts treating different types of desalination concentrate was studied under natural sunlight. Synthetic solutions and reverse osmosis (RO) concentrates from brackish water and municipal wastewater desalination facilities were tested to elucidate the impact of water chemistry, operating conditions and seasonal climate variations (solar irradiation intensity and temperature) on photocatalytic efficiency. High ionic strength and divalent electrolyte ions in RO concentrate accelerated photocatalytic process, whereas the presence of carbonate species and organic matter hindered photodegradation. Outdoor testing of immobilized continuous-flow photoreactors suggested that the catalyst-coated SOFs can utilize a wide spectrum of natural sunlight and achieved durable photocatalytic performance. © 2016 The American Society of Photobiology.

  10. Summit crater lake observations, and the location, chemistry, and pH of water samples near Mount Chiginagak volcano, Alaska: 2004-2012

    Science.gov (United States)

    Schaefer, Janet R.; Scott, William E.; Evans, William C.; Wang, Bronwen; McGimsey, Robert G.

    2013-01-01

    maximum depth of 45 m (resulting pH ~2.9), and preventing the annual salmon run in the King Salmon River. A simultaneous release of gas and acidic aerosols from the crater caused widespread vegetation damage along the flow path. Since 2005, we have been monitoring the crater lake water that continues to flow into Mother Goose Lake by collecting surface water samples for major cation and anion analysis, measuring surface-water pH of affected drainages, and photo-documenting the condition of the summit crater lake. This report describes water sampling locations, provides a table of chemistry and pH measurements, and documents the condition of the summit crater between 2004 and 2011. In September 2013, the report was updated with results of water-chemistry samples collected in 2011 and 2012, which were added as an addendum.

  11. SPARC-IGAC Symposium on Climate-Chemistry Interactions. Climate Feedback by Water Vapor in the Tropical Upper Troposphere

    Science.gov (United States)

    Dessler, A. E.; Minschwaner, K.

    2003-01-01

    The strong greenhouse forcing by atmospheric water vapor is expected to play an important role in shaping the direction of any future changes in climate. We present calculations that provide a new perspective on the sensitivity of upper tropospheric water vapor to changes in surface temperature. Equilibrium states of our atmospheric model show unambiguously that as the surface warms, changes in the vertical distribution and temperature of detraining air parcels from tropical convection lead to higher water vapor mixing ratios in the upper troposphere. However, the increase in mixing ratio is not as large as the increase in saturation mixing ratio due to warmer environmental temperatures, so that the relative humidity decreases. Our analysis suggests that models that maintain a fixed relative humidity are likely overestimating the magnitude of the water vapor feedback.

  12. Near shore water chemistry data from Island of Hawaii and Lanai 1988-2011 (NODC Accession 0104398)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Coastal water quality was measured at seven shoreline locations on the west side of the Island of Hawaii and one site on Lanai, Hawaii during 1988-2011. Each...

  13. Groundwater contamination and the relationship between water chemistry and biotic components in a karst system (Bihor Mountains, Romania

    Directory of Open Access Journals (Sweden)

    Laura Epure

    2014-12-01

    Full Text Available The physical and chemical characteristics, microbial contaminat ion, and meiofauna of the Ocoale-Gheţar-Dobreşti karst system (Bihor Mountains, Romania were studied in order to assess the natural water quality by an interdisciplinary study. A total of 60 water samples were collected seasonally from 7 sites. Physico-chemical results showed a typical composition of karst waters, except for one site, where Ca2+ was absent, pH was very low, and the abundance and diversity of meiofauna were highest, demonstrating life support even for the most sensitive animals. No significant chemical pollution was found, but microbial contamination occurred in all samples, according to the national water quality standards of the analyzed springs. The Canonical Correlation Analysis and the Canonical Correspondence Analysis performed showed a strong connection between pH, nitrates and faecal pollution, indicating also a direct connection between microbial contaminants and dissolved oxygen.

  14. Improved prediction of vegetation composition in NW European softwater lakes by combining location, water and sediment chemistry

    DEFF Research Database (Denmark)

    Pulido Pérez, Cristina; Jensen, Kaj Sand; Lucassen, Esther C.H.E.T.

    2012-01-01

    with environmental variables for surface water, porewater and sediment significantly improved prediction of vegetation composition. Specifically, the combination of latitude, surface water alkalinity, porewater phosphate and redox potential offered the highest correlation (BIO ENV correlation 0.66) to vegetation......Isoetids, as indicators of near-pristine softwater lakes, have a high priority in national and international (European Water Directive Framework) assessments of ecological lake quality. Our main goal was to identify the most important environmental factors that influence the composition of plant...... communities and specifically determine the presence and abundance of the isoetid Lobelia dortmanna in NW European softwater lakes. Geographical position and composition of surface water, porewater, sediment and plant communities were examined in 39 lakes in four regions (The Netherlands, Denmark, West Norway...

  15. [Relationship between groundwater quality index of physics and chemistry in riparian zone and water quality in river].

    Science.gov (United States)

    Xu, Hua-Shan; Zhao, Tong-Qian; Meng, Hong-Qi; Xu, Zong-Xue; Ma, Chao-Hong

    2011-03-01

    Riparian zone hydrology is dominated by shallow groundwater with complex interactions between groundwater and surface water. There are obvious relations of discharge and recharge between groundwater and surface water. Flood is an important hydrological incident that affects groundwater quality in riparian zone. By observing variations of physical and chemical groundwater indicators in riparian zone at the Kouma section of the Yellow River Wetland, especially those took place in the period of regulation for water and sediment at the Xiaolangdi Reservoir, relationship between the groundwater quality in riparian zone and the flood water quality in the river is studied. Results show that, affected by the river and pond water, the highest point of groundwater temperature is near the pond in spring, and near the river in winter; and regulation for water and sediment at the Xiaolangdi Reservoir also affects groundwater temperature in riparian zone, which reaches its maximum at 100 m far from the river bank. There exists a strong zone of nitrification area at 50 m from the river bank, and in this area, the groundwater pH value is lower by 0.2 to 0.4 unit than that of the other regions, with great annual varieties. The turbidity of groundwater is affected by irrigation, which is more obvious than other indicators of groundwater. The turbidity of groundwater and river water increase rapidly during the early phase of flood retreat, and slope stability of river bank is the initial impact of the soil erosion of river bank. Conductivity, chloride and sulfate data show that the range of 50-200 m in riparian wetland is a very important salt accumulation zone, and the width of salt accumulation zone changes with seasons, and this area is also a very important zone of sulfur reduction. The quality of groundwater at 200 m from the river bank is also significantly affected by floods. Physical and chemical indicators of water change strongly in this area. The result indicates that

  16. Vigilancia de la calidad del agua para consumo humano en Colombia: desafíos para la salud ambiental/ Surveillance of drinking water quality in Colombia: challenges for environmental health

    Directory of Open Access Journals (Sweden)

    Blanca L. Guzmán B.

    2016-05-01

    Full Text Available Resumen Objetivo: analizar las experiencias de las autoridades de salud en el ejercicio de la vigilancia del agua de consumo en Colombia, para comprender sus fortalezas y dificultades. Metodología: La investigación se realizó a través de un estudio cualitativo de los componentes de estructura, procesos y resultados del programa de vigilancia. Se construyó un cuestionario mediante la metodología Delphi, aplicado a los coordinadores de la vigilancia en 12 municipios y 27 departamentos. Resultados: se obtuvieron mediante la metodología de análisis de contenido, identificando 3 temáticas relevantes que influyen en la implementación de la vigilancia, entre ellos la descentralización, limitaciones en el recurso humano y la aplicación de las herramientas de evaluación del riesgo. Discusión: el programa de vigilancia en Colombia requiere el fortalecimiento de la rectoría, la capacidad de gestión de los territorios, el establecimiento de una efectiva descentralización y fortalecimiento de la gobernanza, además de instaurar mecanismos que regulen la problemática de recurso humano y evalúen las herramientas de análisis de riesgo y sus resultados. / Abstract Objective: to analyze the experiences of health authorities in the exercise of surveillance of drinking water quality in Colombia, with the aim of understanding the strengths and difficulties of its implementation. Methodology: the research was conducted through a qualitative study of the components of structure, processes and results of the surveillance program. A questionnaire was built using the Delphi methodology and applied to surveillance coordinators in 12 municipalities and 27 departments. Results: The results were obtained through the content analysis methodology, and three relevant issues affecting the implementation of surveillance were identified, namely: decentralization, limitations in human resources and the application of risk assessment tools. Discussion: the

  17. Water quality, organic chemistry of sediment, and biological conditions of streams near an abandoned wood-preserving plant site at Jackson, Tennessee

    Science.gov (United States)

    Bradfield, A.D.; Flexner, N.M.; Webster, D.A.

    1993-01-01

    An investigation of water quality, organic sediment chemistry, and biological conditions of streams near an abandoned wood-preserving plant site at Jackson, Tennessee, was conducted during December 1990. The study was designed to assess the extent of possible contamination of water and biota in the streams from creosote-related discharge originating at this Superfund site. Central Creek, adjacent to the plant, had degraded water quality and biological conditions. Water samples from the most downstream station on Central Creek contained 30 micrograms per liter of pentachlorophenol, which exceeds the State's criterion maximum concentrations of 9 micrograms per liter for fish and aquatic life. Bottom-sediment samples from stations on Central Creek contained concentrations of acenaphthene, napthalene, and phenanthrene ranging from 1,400 to 2,500 micrograms per kilogram. Chronic or acute toxicity resulted during laboratory experiments using test organisms exposed to creosote-related contaminants. Sediment elutriate samples from Central Creek caused slightly to highly toxic effects on Ceriodaphnia dubia. Pimephales promelas, and Photobacterium phosphoreum. Fish-tissue samples from this station contained concentrations of naphthalene. dibenzofuran, fluorene, and phenanthrene ranging from 1.5 to 3.9 micrograms per kilogram Blue-green algae at this station represented about 79 percent of the organisms counted, whereas diatoms accounted for only 11 percent. Benthic invertebrate and fish samples from Central Creek had low diversity and density. Sediment samples from a station on the South Fork Forked Deer River downstream from its confluence with Central Creek contained concentrations of acenaphthene, anthracene, chrysene, fluoranthene, fluorene, pyrere, and phenanthrene ranging from 2,800 to 69,000 micrograms per kilogram. Sediment elutriate samples using water as elutriate from this station contained concentrations of extractable organic compounds ranging from an estimated

  18. Water quality in the vicinity of Mosquito Creek Lake, Trumbull County, Ohio, in relation to the chemistry of locally occurring oil, natural gas, and brine

    Science.gov (United States)

    Barton, G.J.; Burruss, R.C.; Ryder, R.T.

    1998-01-01

    Environmental samples collected in the Mosquito Creek Lake area were used to characterize water quality in relation to the chemistry of locally occurring oil, natural gas, and brine and to establish baseline water quality. Mosquito Creek Lake (a manmade reservoir) and the shallow bedrock aquifers near the lake are major sources of potable water in central Trumbull County. The city of Warren relies on the lake as a sole source of potable water. Some of the lake bottom may be in direct hydraulic connection with the underlying aquifers. The city of Cortland, along the southeastern shore of the lake, relies on the Cussewago Sandstone aquifer as a sole source of potable water. This aquifer subcrops beneath the glacio-fluvial sediments that underlie the lake. Nearly all residential homes around the lake, with the exception of homes in the city of Cortland, rely on domestic supply wells as a source of potable water. Oil and natural gas exploration and production have been ongoing in the Mosquito Creek Lakearea since the discovery of the historic Mecca Oil Pool in the Mississippian Berea and Cussewago Sandstones in 1860. Since the late 1970' s, the major drilling objective and zone of production is the Lower Silurian Clinton sandstone. The oil and natural gas resources of the Mosquito Creek Lake area, including reservoir pressure, production history, and engineering and abandonment practices are described in this report. The chemical and isotopic characteristics of the historic Mecca oil and natural gas are very different than those of the Clinton sandstone oil and natural gas. Gas chromatograms show that Mecca oil samples are extensively altered by biodegradation, whereas Clinton sandstone oils are not. Extensive alteration of Mecca oil is consistent with their occurrence at very shallow depths (less than 100 ft below land surface) where microbial activity can affect their composition. Also, the carbon-isotope composition of dissolved methane gas from Berea and Cussewago

  19. Effect of deforestation on stream water chemistry in the Skrzyczne massif (the Beskid Śląski Mountains in southern Poland).

    Science.gov (United States)

    Kosmowska, Amanda; Żelazny, Mirosław; Małek, Stanisław; Siwek, Joanna Paulina; Jelonkiewicz, Łukasz

    2016-10-15

    The purpose of the study was to identify the factors affecting stream water chemistry in the small mountain catchments deforested to varying degrees, from 98.7 to 14.1%, due to long-term acid deposition. Water samples were collected monthly in 2013 and 2014 from 17 streams flowing across three distinct elevation zones in the Skrzyczne massif (Poland): Upper, Middle and Lower Forest Zone. Chemical and physical analyses, including the pH, electrical conductivity (EC), total mineral content (Mt), water temperature, and the concentrations of Ca(2+), Mg(2+), Na(+), K(+), HCO3(-), SO4(2-), Cl(-), and NO3(-), were conducted. Based on Principal Component Analysis (PCA), the most important factor affecting water chemistry was human impact associated with changes in pH, SO4(2-) concentration, and the concentration of most of the main ions. The substantial acidity of the studied environment contributed to the exclusion of natural factors, associated with changes in discharge, from the list of major factors revealed by PCA. All of the streams were characterized by very low EC, Mt, and low concentrations of the main ions such as Ca(2+) and HCO3(-). This is the effect of continuous leaching of solutes from the soils by acidic precipitation. The lowest parameter values were measured for the streams situated in the Upper Forest Zone, which is associated with greater acid deposition at the higher elevations. In the streams located in the Upper Forest Zone, a higher percentage of SO4(2-) occurred than in the streams situated in the Middle and Lower Forest Zones. However, the largest share of SO4(2-) was measured in the most deforested catchment. The saturation of the studied deforested catchment with sulfur compounds is reflected by a positive correlation between SO4(2-) and discharge. Hence, a forest acts as a natural buffer that limits the level of acidity in the natural environment caused by acidic atmospheric deposition. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. Master schedule for CY-1980 Hanford Environmental Surveillance Routine Program

    Energy Technology Data Exchange (ETDEWEB)

    Blumer, P.J.; Houston, J.R.; Eddy, P.A.

    1979-12-01

    The current schedule of data collection for the routine environmental surveillance program at the Hanford Site is presented. The enviromental surveillance program objectives are to evaluate the levels of radioactive and nonradioactive pollutants in the Hanford environs, as required in Manual Chapter 0513, and to monitor Hanford operations for compliance with applicable environmental criteria given in Manual Chapter 0524 and Washington State Water Quality Standards. Data are reported on the following topics: air; Columbia River; sanitary water; surface water; ground water; foodstuffs; wildlife; soil and vegetation; external radiation measurement; portable instrument surveys; and surveillance of waste disposal sites;

  1. Goodenough Spring, Texas, USA: Discharge and water chemistry of a large spring deeply submerged under the binational Amistad Reservoir

    Science.gov (United States)

    Kamps, Ray H.; Tatum, Gregg S.; Gault, Mike; Groeger, Alan W.

    2009-06-01

    Goodenough Spring (Texas, USA) is a large spring near the border of the American state of Texas and the Mexican state of Coahuila, discharging into the international Amistad Reservoir on the river Rio Grande (Rio Bravo). Discharge was routinely measured from 1928 until 1968 to partition the flow of the river between the two countries in accordance with water-use treaties. Samples were analyzed for water-quality parameters in 1967-1968 prior to inundation under 45 m of Amistad Reservoir in 1968. Subsequently, discharge has been estimated indirectly by the International Boundary and Water Commission (IBWC). For the first direct measurements of the spring in 37 years, velocity and cross-sectional measurements were made and water samples collected in the summer of 2005 using advanced self-contained underwater breathing apparatus (SCUBA) techniques. Spring discharge was calculated at 2.03 m3 s-1, approximately one-half of the historical mean of 3.94 m3 s-1. In situ and laboratory analyses of samples for temperature, pH, dissolved oxygen, specific conductance, alkalinity, nitrate-nitrogen, dissolved solids, chloride, sulfate, fluoride, phosphorus, calcium, sodium, potassium, magnesium, and iron showed the water quality to be very good for human consumption and crop irrigation. Measurement values are relatively unchanged from those reported 37 years prior.

  2. Water-chemistry and chloride fluctuations in the Upper Floridan Aquifer in the Port Royal Sound area, South Carolina, 1917-93

    Science.gov (United States)

    Landmeyer, J.E.; Belval, D.L.

    1996-01-01

    Withdrawal of water from the Upper Floridan aquifer south of Port Royal Sound in Beaufort and Jasper Counties, South Carolina, has lowered water levels and reversed the hydraulic gradient beneath Hilton Head Island, South Carolina. Ground water that had previously discharged at the Sound is now being deflected southwest, toward withdrawals located near the city of Savannah, Georgia, and the island of Hilton Head. The reversal of this hydraulic gradient and the decline of water levels have caused saltwater in the Upper Floridan aquifer north of Port Royal Sound to begin moving southwest, toward water-supply wells for the town of Hilton Head and toward industries pumping ground water near Savannah. Analytical results from ground-water samples collected from wells in the Upper Floridan aquifer beneath and adjacent to Port Royal Sound show two plumes in the aquifer with chloride concentrations above the drinking- water standard. One plume of high chloride concentration extends slightly south of the theoretical predevelopment location of the steady- state freshwater-saltwater interface as indicated by numerical modeling. The other plume is present beneath the town of Port Royal, where the upper confining unit above the Upper Floridan aquifer is thin or absent. In these areas, the decline in water levels caused by ground-water withdrawals may have made it possible for water from tidal creeks to enter the Upper Floridan aquifer. Many wells completed in the upper permeable zone of the Upper Floridan aquifer show a distinct specific- conductance profile. One non-producing, monitoring well on Hilton Head Island (BFT-1810) was selected to depict a worst-case scenario to examine the short- and long-term water-chemistry and chloride fluctuations in the aquifer. Specific conductance was monitored at depths of 170, 190, and 200 feet below the top of the well casing. The specific conductance measured in 1987 ranged from approximately 450 microsiemens per centimeter near the top of

  3. Reassembling Surveillance Creep

    DEFF Research Database (Denmark)

    Bøge, Ask Risom; Lauritsen, Peter

    2017-01-01

    We live in societies in which surveillance technologies are constantly introduced, are transformed, and spread to new practices for new purposes. How and why does this happen? In other words, why does surveillance “creep”? This question has received little attention either in theoretical developm......We live in societies in which surveillance technologies are constantly introduced, are transformed, and spread to new practices for new purposes. How and why does this happen? In other words, why does surveillance “creep”? This question has received little attention either in theoretical...... development or in empirical analyses. Accordingly, this article contributes to this special issue on the usefulness of Actor-Network Theory (ANT) by suggesting that ANT can advance our understanding of ‘surveillance creep’. Based on ANT’s model of translation and a historical study of the Danish DNA database......, we argue that surveillance creep involves reassembling the relations in surveillance networks between heterogeneous actors such as the watchers, the watched, laws, and technologies. Second, surveillance creeps only when these heterogeneous actors are adequately interested and aligned. However...

  4. Surveillance of respiratory viruses.

    African Journals Online (AJOL)

    Surveillance of respiratory viruses. A 10-year laboratory-based study. J. M. McAnerney, S. Johnson, B. D. Schoub. Respiratory virus isolates made at the National Institute for. Virology from 1982 to 1991 were studied. An active virus surveillance programme, 'viral watch', which recruits throat swab specimens from a network ...

  5. Surveillance Avoidance Technique Demonstration.

    Science.gov (United States)

    1983-12-02

    path and, using the evaluation module for feedback , alter the path until acceptable surveil- lance avoidance performance is achieved. The current ISAS...Nmber Diselav Stage Containing - Date: I I Time ( GIlT ): Figure 3-46: Textual Display for GRAPHICAL Module 3-64 Surveillance Avoidance Final Report System

  6. Soil and vegetation surveillance

    Energy Technology Data Exchange (ETDEWEB)

    Antonio, E.J.

    1995-06-01

    Soil sampling and analysis evaluates long-term contamination trends and monitors environmental radionuclide inventories. This section of the 1994 Hanford Site Environmental Report summarizes the soil and vegetation surveillance programs which were conducted during 1994. Vegetation surveillance is conducted offsite to monitor atmospheric deposition of radioactive materials in areas not under cultivation and onsite at locations adjacent to potential sources of radioactivity.

  7. Chemistry of runoff and shallow ground water at the Cattlemans Detention basin site, South Lake Tahoe, California, August 2000-November 2001

    Science.gov (United States)

    Prudic, David E.; Sager, Sienna J.; Wood, James L.; Henkelman, Katherine K.; Caskey, Rachel M.

    2005-01-01

    A study at the Cattlemans detention basin site began in November 2000. The site is adjacent to Cold Creek in South Lake Tahoe, California. The purpose of the study is to evaluate the effects of the detention basin on ground-water discharge and changes in nutrient loads to Cold Creek, a tributary to Trout Creek and Lake Tahoe. The study is being done in cooperation with the Tahoe Engineering Division of the El Dorado County Department of Transportation. This report summarizes data collected prior to and during construction of the detention basin and includes: (1) nutrient and total suspended solid concentrations of urban runoff; (2) distribution of unconsolidated deposits; (3) direction of ground-water flow; and (4) chemistry of shallow ground water and Cold Creek. Unconsolidated deposits in the area of the detention basin were categorized into three classes: fill material consisting of a red-brown loamy sand with some gravel and an occasional cobble that was placed on top of the meadow; meadow deposits consisting of gray silt and sand with stringers of coarse sand and fine gravel; and a deeper brown to yellow-brown sand and gravel with lenses of silt and sand. Prior to construction of the detention basin, ground water flowed west-northwest across the area of the detention basin toward Cold Creek. The direction of ground-water flow did not change during construction of the detention basin. Median concentrations of dissolved iron and chloride were 500 and 30 times higher, respectively, in ground water from the meadow deposits than dissolved concentrations in Cold Creek. Median concentration of sulfate in ground water from the meadow deposits was 0.4 milligrams per liter and dissolved oxygen was below the detection level of 0.3 milligrams per liter. The relatively high concentrations of iron and the lack of sulfate in the shallow ground water likely are caused by chemical reactions and biological microbial oxidation of organic matter in the unconsolidated deposits

  8. Effects of multiple stresses hydropower, acid deposition and climate change on water chemistry and salmon populations in the River Otra, Norway.

    Science.gov (United States)

    Wright, Richard F; Couture, Raoul-Marie; Christiansen, Anne B; Guerrero, José-Luis; Kaste, Øyvind; Barlaup, Bjørn T

    2017-01-01

    Many surface waters in Europe suffer from the adverse effects of multiple stresses. The Otra River, southernmost Norway, is impacted by acid deposition, hydropower development and increasingly by climate change. The river holds a unique population of land-locked salmon and anadromous salmon in the lower reaches. Both populations have been severely affected by acidification. The decrease in acid deposition since the 1980s has led to partial recovery of both populations. Climate change with higher temperatures and altered precipitation can potentially further impact fish populations. We used a linked set of process-oriented models to simulate future climate, discharge, and water chemistry at five sub-catchments in the Otra river basin. Projections to year 2100 indicate that future climate change will give a small but measureable improvement in water quality, but that additional reductions in acid deposition are needed to promote full restoration of the fish communities. These results can help guide management decisions to sustain key salmon habitats and carry out effective long-term mitigation strategies such as liming. The Otra River is typical of many rivers in Europe in that it fails to achieve the good ecological status target of the EU Water Framework Directive. The programme of measures needed in the river basin management plan necessarily must consider the multiple stressors of acid deposition, hydropower, and climate change. This is difficult, however, as the synergistic and antagonistic effects are complex and challenging to address with modelling tools currently available. Copyright © 2016 Elsevier B.V. All rights reserved.

  9. Significance of ground-water chemistry in performance of North Sahara Tube wells in Algeria and Tunisia

    Science.gov (United States)

    Clarke, Frank Eldridge; Jones, Blair F.

    1972-01-01

    Nine ground-water samples from the principal shallow and deep North Sahara aquifers of Algeria and Tunisia were examined to determine the relation of their chemical composition to corrosion and mineral encrustation thought to be contributing to observed decline in well capacities within a UNESCO/UNDP Special Fund Project area. Although the shallow and deep waters differ significantly in certain quality factors, all are sulfochloride types with corrosion potentials ranging from moderate to extreme. None appear to be sufficiently supersaturated with troublesome mineral species to cause rapid or severe encrustation of filter pipes or other well parts. However, calcium carbonate encrustation of deep-well cooling towers and related irrigation pipes can be expected because of loss of carbon dioxide and water during evaporative cooling. Corrosion products, particularly iron sulfide, can be expected to deposit in wells producing waters from the deep aquifers. This could reduce filterpipe openings and increase casing roughness sufficiently to cause significant reduction in well capacity. It seems likely, however, that normal pressure reduction due to exploitation of the artesian systems is a more important control of well performance. If troublesome corrosion and related encrustation are confirmed by downhole inspection, use of corrosion-resisting materials, such as fiber-glass casing and saw-slotted filter pipe (shallow wells only), or stainless-steel screen, will minimize the effects of the waters represented by these samples. A combination of corrosion-resisting stainless steel filter pipe electrically insulated from the casing with a nonconductive spacer and cathodic protection will minimize external corrosion of steel casing, if this is found to be a problem. However, such installations are difficult to make in very deep wells and difficult to control in remote areas. Both the shallow waters and the deep waters examined in this study will tend to cause soil

  10. Unconventional natural gas development did not result in detectable changes in water chemistry (within the South Fork Little Red River).

    Science.gov (United States)

    Austin, Bradley J; Scott, Erin; Massey, Leslie; Evans-White, Michelle A; Entrekin, Sally; Haggard, Brian E

    2017-05-01

    The Fayetteville Shale within north central Arkansas is an area of extensive unconventional natural gas (UNG) production. Recently, the Scott Henderson Gulf Mountain Wildlife Management Area (GMWMA) was leased from the state of Arkansas for NG exploration, raising concerns about potential impacts on water resources. From November 2010 through November 2014, we monitored four reaches of the South Fork Little Red River (SFLRR), within the GMWMA, establishing baseline physico-chemical characteristics prior to UNG development and assessing trends in parameters during and after UNG development. Water samples were collected monthly during baseflow conditions and analyzed for conductivity, turbidity, ions, total organic carbon (TOC), and metals. All parameters were flow-adjusted and evaluated for monotonic changes over time. The concentrations of all constituents measured in the SFLRR were generally low (e.g., nitrate ranged from <0.005 to 0.268 mg/l across all sites and sample periods), suggesting the SFLRR is of high water quality. Flow-adjusted conductivity measurements and sodium concentrations increased at site 1, while magnesium decreased across all four sites, TOC decreased at sites 1 and 3, and iron decreased at site 1 over the duration of the study. With the exception of conductivity and sodium, the physico-chemical parameters either decreased or did not change over the 4-year duration, indicating that UNG activities within the GMWMA have had minimal or no detectable impact on water quality within the SFLRR. Our study provides essential baseline information that can be used to evaluate water quality within the SFLRR in the future should UNG activity within the GMWMA expand.

  11. Polymer Chemistry

    Science.gov (United States)

    Williams, Martha; Roberson, Luke; Caraccio, Anne

    2010-01-01

    This viewgraph presentation describes new technologies in polymer and material chemistry that benefits NASA programs and missions. The topics include: 1) What are Polymers?; 2) History of Polymer Chemistry; 3) Composites/Materials Development at KSC; 4) Why Wiring; 5) Next Generation Wiring Materials; 6) Wire System Materials and Integration; 7) Self-Healing Wire Repair; 8) Smart Wiring Summary; 9) Fire and Polymers; 10) Aerogel Technology; 11) Aerogel Composites; 12) Aerogels for Oil Remediation; 13) KSC's Solution; 14) Chemochromic Hydrogen Sensors; 15) STS-130 and 131 Operations; 16) HyperPigment; 17) Antimicrobial Materials; 18) Conductive Inks Formulations for Multiple Applications; and 19) Testing and Processing Equipment.

  12. Influence of water chemistry on the distribution of an acidophilic protozoan in an acid mine drainage system at the abandoned Green Valley coal mine, Indiana, USA

    Energy Technology Data Exchange (ETDEWEB)

    Brake, S.S.; Dannelly, H.K.; Connors, K.A.; Hasiotis, S.T. [Indiana State University, Terre Haute, IN (United States). Dept. of Geography Geology & Anthropology

    2001-07-01

    Euglena mutabilis, a benthic photosynthetic protozoan that intracellularly sequesters Fe, is variably abundant in the main effluent channel that contains acid mine drainage (AMD) discharging from the Green Valley coal mine site in western Indiana. Samples of effluent (pH 3.0-4.6) taken from the main channel and samples of contaminated stream water (pH 3.3 to 8.0) collected from an adjacent stream were analyzed to evaluate the influence of water chemistry on E. mutabilis distribution. E. mutabilis communities were restricted to areas containing unmixed effluent with the thickest (up to 3 mm) benthic communities residing in effluent containing high concentrations of total Fe (up to 12110 mg/l), SO{sub 4}(up to 2940 mg/l), Al (up to 1846 mg/l), and Cl (up to 629 mg/l). Communities were also present, but much less abundant, in areas with effluent containing lower concentrations of these same constituents. In effluent where SO{sub 4} was most highly concentrated, E. mutabilis was largely absent, suggesting that extremely high concentrations of SO{sub 4} may have an adverse effect on this potentially beneficial Fe-mediating, acidophilic protozoan.

  13. Linking local riverbed flow patterns and pore-water chemistry to hydrogeologic and geomorphic features across scales

    Science.gov (United States)

    Ibrahim, T. G.; Thornton, S.; Surridge, B.; Wainwright, J.

    2009-12-01

    The groundwater-surface water interface (GSI) is a critical environmental hotspot, a key area influencing the fate of carbon, nutrients and contaminants of surface and subsurface origin, and a zone of ecological importance. Policy seeking to mitigate issues relating to dissolved contaminants and to improve stream health, increasingly recognizes its significance, particularly in the context of integrated management of streams and aquifers. Techniques assessing riverbed flow and solute patterns are often limited to the local scale. When related to the multi-scale pattern of hydrogeologic and geomorphic features controlling stream, hyporheic and groundwater fluxes, they can improve larger scale predictions of flow and solute behaviour at the GSI. This study develops a conceptual model of riverbed flow and solute patterns, and tests it in a 4th order stream in the UK. It assesses the interaction between large scale subsurface flowpaths, driven by the distribution of bedrock outcrops, and the expansion and closure of alluvial deposits, and small-scale hyporheic flowpaths, driven by riffle-pool sequences. It uses two networks of riverbed mini-piezometers and multi-level samplers: network 1, across fifteen sites in a 7.2 km length of river in unconstrained (open alluvial valley), asymmetric (bedrock outcropping on one bank) and constrained (bedrock on both banks) contexts; and network 2, across six riffle-pool sequences in a 350-m reach, at the transition between asymmetric/unconstrained and constrained contexts. Subsurface flowpaths and stream-water infiltration were deduced by relating vertical exchange fluxes to stream and pore-water patterns of conservative natural tracers. Biogeochemical processes were highlighted using reactive natural tracers. At network 2, measurements of surface water profiles and riverbed coring were also undertaken, and dissolved metal concentrations in the first 15 cm of sediments assessed using gel probes. Network 1 was sampled twice. Monthly

  14. A modern vs. Permian black shale - the hydrography, primary productivity, and water-column chemistry of deposition

    Science.gov (United States)

    Piper, D.Z.; Perkins, R.B.

    2004-01-01

    The sediment currently accumulating in the Cariaco Basin, on the continental shelf of Venezuela, has an elevated organic-carbon content of approximately 5%; is accumulating under O2-depleted bottom-water conditions (SO42- reduction); is composed dominantly of foraminiferal calcite, diatomaceous silica, clay, and silt; and is dark greenish gray in color. Upon lithification, it will become a black shale. Recent studies have established the hydrography of the basin and the level of primary productivity and bottom-water redox conditions. These properties are used to model accumulation rates of Cd, Cr, Cu, Mo, Ni, V, and Zn on the seafloor. The model rates agree closely with measured rates for the uppermost surface sediment.The model is applied to the Meade Peak Phosphatic Shale Member of the Phosphoria Formation, a phosphate deposit of Permian age in the northwest United States. It too has all of the requisite properties of a black shale. Although the deposit is a world-class phosphorite, it is composed mostly of phosphatic mudstone and siltstone, chert, limestone, and dolomite. It has organic-carbon concentrations of up to 15%, is strongly enriched in several trace elements above a terrigenous contribution and is black. The trace-element accumulation defines a mean primary productivity in the photic zone of the Phosphoria Basin as moderate, at 500 g m-2 year-1 organic carbon, comparable to primary productivity in the Cariaco Basin. The source of nutrient-enriched water that was imported into the Phosphoria Basin, upwelled into the photic zone, and supported primary productivity was an O2 minimum zone of the open ocean. The depth range over which the water was imported would have been between approximately 100 and 600 m. The mean residence time of bottom water in the basin was approximately 4 years vs. 100 years in the Cariaco Basin. The bottom water was O2 depleted, but it was denitrifying, or NO3- reducing, rather than SO42- reducing. Published by Elsevier B.V.

  15. National Coral Reef Monitoring Program: Water Chemistry of the Coral Reefs in the Pacific Remote Island Areas from Water Samples collected since 2014

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Water samples are collected and analyzed to assess spatial and temporal variation in the seawater carbonate systems of coral reef ecosystems in the Hawaiian and...

  16. National Coral Reef Monitoring Program: Water Chemistry of the Coral Reefs in the Hawaiian Archipelago from Water Samples collected since 2013

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Water samples are collected and analyzed to assess spatial and temporal variation in the seawater carbonate systems of coral reef ecosystems in the Hawaiian and...

  17. National Coral Reef Monitoring Program: Water Chemistry of the Coral Reefs in the Mariana Archipelago from Water Samples collected in 2014

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Water samples are collected and analyzed to assess spatial and temporal variation in the seawater carbonate systems of coral reef ecosystems in the Hawaiian and...

  18. Food carbohydrate chemistry

    National Research Council Canada - National Science Library

    Wrolstad, R. E

    2012-01-01

    .... Now in Food Carbohydrate Chemistry, author Wrolstad emphasizes the application of carbohydrate chemistry to understanding the chemistry, physical and functional properties of food carbohydrates...

  19. The one-dimensional compression method for extraction of pore water from unsaturated tuff and effects on pore-water chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Higgins, J.D.; Burger, P.A. [Colorado School of Mines, Golden, CO (United States); Yang, L.C. [Geological Survey, Denver, CO (United States)

    1997-12-31

    Study of the hydrologic system at Yucca Mountain, Nevada, requires extraction of pore-water samples from unsaturated tuff bedrock. Two generations of compression cells have been designed and tested for extracting representative, unaltered pore-water samples from unsaturated tuff cores. The one-dimensional compression cell has a maximum compressive stress rating of 552 MPa. Results from 86 tests show that the minimum degree of saturation for successful extraction of pore water was about 14% for non welded tuff and about 61% for densely welded tuff. The high-pressure, one-dimensional compression cell has a maximum compressive stress rating of 827 MPa. Results from 109 tests show that the minimum degree of saturation for successful extraction of pore water was about 7.5% for non welded tuff and about 34% for densely welded tuff. Geochemical analyses show that, in general, there is a decrease in ion concentration of pore waters as extraction pressures increase. Only small changes in pore-water composition occur during the one-dimensional extraction test.

  20. Heavy metal contents in the sediments of astatic ponds: Influence of geomorphology, hydroperiod, water chemistry and vegetation.

    Science.gov (United States)

    Gołdyn, Bartłomiej; Chudzińska, Maria; Barałkiewicz, Danuta; Celewicz-Gołdyn, Sofia

    2015-08-01

    The contents of heavy metals (Cd, Cr, Cu, Ni, Pb, Zn) were analysed in the bottom sediments of 30 small, astatic ponds located in the agricultural landscape of Western Poland. The samples were collected from 118 stations located in patches of four vegetation types. Relationships between the contents of particular elements and four groups of factors (geomorphology, hydroperiod, water quality and vegetation) were tested using Redundancy Analysis (RDA). The most important factors influencing the heavy metal contents were the maximum depth and area of the pond, its hydroperiod, water pH and conductivity values. In general, low quantities of heavy metals were recorded in the sediments of kettle-like ponds (small but located in deep depressions) and high in water bodies of the shore-bursting type (large but shallow). Moreover, quantities of particular elements were influenced by the structure of the vegetation covering the pond. Based on the results, we show which types of astatic ponds are most exposed to contamination and suggest some conservation practices that may reduce the influx of heavy metals. Copyright © 2015 Elsevier Inc. All rights reserved.

  1. Trends in Ostracoda and Cladocera distribution and water chemistry in subarctic Canada: Churchill (Manitoba lakes and ponds revisited

    Directory of Open Access Journals (Sweden)

    Finn A. Viehberg

    2017-03-01

    Full Text Available Ponds and lakes distributed across northern treeline in the Hudson Bay Lowlands near Churchill (Manitoba were revisited to analyse and document the local ecoclimatic and limnological changes that occurred over the period 1997-2012. Our analyses revealed that single events may cause significant changes in salinity, pH and silicate content because of the limited buffer capacity of the inter-connected waters. Planktic freshwater microcrustaceans (Cladocera presented less diverse assemblages and appeared to favour waters that are situated in the boreal forest, while the diversity of benthic species assemblages (Cladocera and Ostracoda was highest in waters located closer to the coastline and in open tundra vegetation. We identified three species that are distinctive for the boreal ecozone (i.e., Candona acuta, Can. acutula and Can. decora and two species (i.e., Tonnacypris glacialis and Can. rawsoni that are elements of (sub-arctic landscapes and potentially endangered as the northern treeline expands due to rapid warming. These species are thought to be useful indicators for future ecosystem quality assessments and/or ecosystem service management programs. Our findings were compared to other studies completed in the boreal Yukon Territory and revealed that species diversity is closely linked to landscape history.

  2. Oxidizing dissolution of spent MOX47 fuel subjected to water radiolysis: Solution chemistry and surface characterization by Raman spectroscopy

    Science.gov (United States)

    Jégou, C.; Caraballo, R.; De Bonfils, J.; Broudic, V.; Peuget, S.; Vercouter, T.; Roudil, D.

    2010-04-01

    The mechanisms of oxidizing dissolution of spent MOX fuel (MIMAS TU2®) subjected to water radiolysis were investigated experimentally by leaching spent MOX47 fuel samples in pure water at 25 °C under different oxidizing conditions (with and without external gamma irradiation); the leached surfaces were characterized by Raman spectroscopy. The highly oxidizing conditions resulting from external gamma irradiation significantly increased the concentration of plutonium (Pu(V)) and uranium (U(VI)) compared with a benchmark experiment (without external irradiation). The oxidation behavior of the plutonium-enriched aggregates differed significantly from that of the UO 2 matrix after several months of leaching in water under gamma irradiation. The plutonium in the aggregates appears to limit fuel oxidation. The only secondary phases formed and identified to date by Raman spectroscopy are uranium peroxides that generally precipitate on the surface of the UO 2 grains. Concerning the behavior of plutonium, solution analysis results appear to be compatible with a conventional explanation based on an equilibrium with a Pu(OH) 4(am) phase. The fission product release - considered as a general indicator of matrix alteration - from MOX47 fuel also increases under external gamma irradiation and a change in the leaching mode is observed. Diffusive leaching was clearly identified, coinciding with the rapid onset of steady-state actinide concentrations in the bulk solution.

  3. Oxidizing dissolution of spent MOX47 fuel subjected to water radiolysis: Solution chemistry and surface characterization by Raman spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Jegou, C., E-mail: christophe.jegou@cea.f [Commissariat a l' Energie Atomique (CEA), Marcoule Reasearch Center, B.P. 17171, F-30207 Bagnols-sur-Ceze Cedex (France); Caraballo, R.; De Bonfils, J.; Broudic, V.; Peuget, S. [Commissariat a l' Energie Atomique (CEA), Marcoule Reasearch Center, B.P. 17171, F-30207 Bagnols-sur-Ceze Cedex (France); Vercouter, T. [Commissariat a l' Energie Atomique (CEA), Saclay Reasearch Center, B.P. 11, F-91191 Gif-sur-Yvette Cedex (France); Roudil, D. [Commissariat a l' Energie Atomique (CEA), Marcoule Reasearch Center, B.P. 17171, F-30207 Bagnols-sur-Ceze Cedex (France)

    2010-04-01

    The mechanisms of oxidizing dissolution of spent MOX fuel (MIMAS TU2 (registered) ) subjected to water radiolysis were investigated experimentally by leaching spent MOX47 fuel samples in pure water at 25 deg. C under different oxidizing conditions (with and without external gamma irradiation); the leached surfaces were characterized by Raman spectroscopy. The highly oxidizing conditions resulting from external gamma irradiation significantly increased the concentration of plutonium (Pu(V)) and uranium (U(VI)) compared with a benchmark experiment (without external irradiation). The oxidation behavior of the plutonium-enriched aggregates differed significantly from that of the UO{sub 2} matrix after several months of leaching in water under gamma irradiation. The plutonium in the aggregates appears to limit fuel oxidation. The only secondary phases formed and identified to date by Raman spectroscopy are uranium peroxides that generally precipitate on the surface of the UO{sub 2} grains. Concerning the behavior of plutonium, solution analysis results appear to be compatible with a conventional explanation based on an equilibrium with a Pu(OH){sub 4(am)} phase. The fission product release - considered as a general indicator of matrix alteration - from MOX47 fuel also increases under external gamma irradiation and a change in the leaching mode is observed. Diffusive leaching was clearly identified, coinciding with the rapid onset of steady-state actinide concentrations in the bulk solution.

  4. Effect of water chemistry on the planktonic communities and relationships among food web components across a freshwater ecotone

    Directory of Open Access Journals (Sweden)

    Mieczan T.

    2013-01-01

    Full Text Available Most ecological research on the food web has been focused more on the pelagic zone than on the transitional zone - ecotones between lentic and lotic habitats. The specific goals of this study were to determine whether the contact zone of waters differs in hydrochemical and biological terms from the waters of the canal and the open water zone, and to evaluate the influence of particular macro-habitats on the interactions between components of the planktonic food web. The distribution of samples in ordination space led us to conclude that the studied habitats are distributed along the rising gradient of total organic carbon and nutrients. Assemblages of all investigated groups showed a strong compositional gradient correlated with conductivity and total phosphorus, while a second strong gradient in species composition was explained by nitrate nitrogen and/or phosphate concentrations. The analysis of trophic relationships in the system bacteriaciliates- crustaceans reveals a clear differentiation and strength of mutual relations between the analyzed zones. The highest number of significant correlations was determined in the contact zone. It can also be a place of very efficient matter and energy flow in freshwater ecosystems.

  5. Confectionary Chemistry.

    Science.gov (United States)

    Levine, Elise Hilf

    1996-01-01

    Presents activities and demonstrations that enable teachers to use various types of confections as tactile experiences to spark chemistry students' interest and generate enthusiasm for learning. Presents uses of candy in teaching about atomic structure, spontaneous nuclear decay, chemical formulas, fractoluminescence, the effect of a molecular…

  6. Chemistry Notes.

    Science.gov (United States)

    School Science Review, 1983

    1983-01-01

    Presents chemistry experiments, laboratory procedures, demonstrations, and classroom materials/activities. These include: experiments on colloids, processing of uranium ore, action of heat on carbonates; color test for phenols and aromatic amines; solvent properties of non-electrolytes; stereoscopic applications/methods; a valency balance;…

  7. Vertical-deformation, water-level, microgravity, geodetic, water-chemistry, and flow-rate data collected during injection, storage, and recovery tests at Lancaster, Antelope Valley, California, September 1995 through September 1998

    Science.gov (United States)

    Metzger, Loren F.; Ikehara, Marti E.; Howle, James F.

    2001-01-01

    A series of freshwater injection, storage, and recovery tests were conducted from September 1995 through September 1998 to evaluate the feasibility of artificially recharging ground water in the Lancaster area of the Antelope Valley, California. The tests used two production wells at a well field located in the southern part of the city of Lancaster. Monitoring networks were established at or in the vicinity of the test site to measure vertical deformation of the aquifer system, water-level fluctuations, land-surface deformation, water chemistry, and injection well flow rates during water injection and recovery. Data presented in this report were collected from a dual extensometer; 10 piezometers; 1 barometer; 27 active or abandoned production wells; 31 gravity stations; 124 bench marks; 1 permanent and 1 temporary continuous Global Positioning System (GPS) station; 3 tiltmeters; and 2 electromagnetic flowmeters from September 1995 through September 1998. This report discusses the location and design of the monitoring networks and the methods used to collect and process the data, and presents the data in tables and graphs.

  8. Internet and Surveillance

    DEFF Research Database (Denmark)

    in the age of the internet; civil watch-surveillance on social networking sites; and networked interactive surveillance in transnational space. This book is a result of a research action launched by the intergovernmental network COST (European Cooperation in Science and Technology)....... institutions have a growing interest in accessing this personal data. Here, contributors explore this changing landscape by addressing topics such as commercial data collection by advertising, consumer sites and interactive media; self-disclosure in the social web; surveillance of file-sharers; privacy...

  9. Risk analysis of a video-surveillance system

    NARCIS (Netherlands)

    Rothkrantz, L.; Lefter, I.

    2011-01-01

    The paper describes a surveillance system of cameras installed at lamppost of a military area. The surveillance system has been designed to detect unwanted visitors or suspicious behaviors. The area is composed of streets, building blocks and surrounded by gates and water. The video recordings are

  10. Environmental control technology survey of selected US strip mining sites. Volume 2A: Ohio: water quality impacts and overburden chemistry of Ohio study site

    Energy Technology Data Exchange (ETDEWEB)

    Bogner, J E; Henricks, J D; Olsen, R D; Schubert, J P; Sobek, A A; Wilkey, M L; Johnson, D O

    1979-05-01

    An intensive study of water, overburden, and coal chemistry was conducted at a large surface mine in Ohio from May 1976 through July 1977. Sampling sites were chosen to include the final mine effluent at the outflow of a large settling pond and chemically-treated drainage from a coal storage pile. Samples were collected semimonthly and analyzed for total dissolved solids, total suspended solids, alkalinity, acidity, sulfate, chloride, and 16 metals. Field measurements included pH, flow rate, dissolved oxygen, and specific conductance. The final effluent, where sampled, generally complied with Office of Surface Mining reclamation standards for pH, iron, and total suspended solids. Comparison of the final effluent with water quality of an unnamed tributary above the mine suggested that elevated values for specific conductance, total dissolved solids, sulfate, calcium, magnesium, manganese, and zinc were attributable to the mine operation. In general, there were observable seasonal variations in flow rates that correlated positively to suspended solids concentrations and negatively to concentrations of dissolved constituents in the final effluent. Drainage from the coal storage pile contained elevated levels of acidity and dissolved metals which were not reduced significantly by the soda ash treatment. The storage pile drainage was diluted, however, by large volumes of alkaline water in the settling pond. Analysis of overburden and coal indicated that the major impact of mine drainage was pyrite oxidation and hydrolysis in the Middle Kittanning Coal and in the Lower Freeport Shale overlying the coal. However, the presence of a calcite-cemented section in the Upper Freeport Sandstone contributed substantial self-neutralizing capacity to the overburden section, resulting in generally alkaline drainage at this site.

  11. Aerosol chemistry and the effect of aerosol water content on visibility impairment and radiative forcing in Guangzhou during the 2006 Pearl River Delta campaign.

    Science.gov (United States)

    Jung, Jinsang; Lee, Hanlim; Kim, Young J; Liu, Xingang; Zhang, Yuanhang; Gu, Jianwei; Fan, Shaojia

    2009-08-01

    Optical and chemical aerosol measurements were obtained from 2 to 31 July 2006 at an urban site in the metropolitan area of Guangzhou (China) as part of the Program of Regional Integrated Experiment of Air Quality over Pearl River Delta (PRIDE-PRD2006) to investigate aerosol chemistry and the effect of aerosol water content on visibility impairment and radiative forcing. During the PRIDE-PRD2006 campaign, the average contributions of ammonium sulfate, organic mass by carbon (OMC), elemental carbon (EC), and sea salt (SS) to total PM(2.5) mass were measured to be 36.5%, 5.7%, 27.1%, 7.8%, and 3.7%, respectively. Compared with the clean marine period, (NH(4))(2)SO(4), NH(4)NO(3), and OMC were all greatly enhanced (by up to 430%) during local haze periods via the accumulation of a secondary aerosol component. The OMC dominance increased when high levels of biomass burning influenced the measurement site while (NH(4))(2)SO(4) and OMC did when both biomass burning and industrial emissions influenced it. The effect of aerosol water content on the total light-extinction coefficient was estimated to be 34.2%, of which 25.8% was due to aerosol water in (NH(4))(2)SO(4), 5.1% that in NH(4)NO(3), and 3.3% that in SS. The average mass-scattering efficiency (MSE) of PM(10) particles was determined to be 2.2+/-0.6 and 4.6+/-1.7m(2)g(-1) under dry (RHurban area.

  12. Effect of water chemistry on zooplanktonic and microbial communities across freshwater ecotones in different macrophyte-dominated shallow lakes

    Directory of Open Access Journals (Sweden)

    Tomasz Mieczan

    2015-12-01

    Full Text Available Complex interactions between zooplankton and microbial food webs are vital to the ecosystem ecology of shallow lakes. However, little is known about how horizontal changes in environmental conditions may influence microbial and metazoan communities in shallow lakes. The specific goals of the study were i to describe environmental variables responsible for the distribution of bacteria, flagellates, ciliates and crustaceans in an adjacent canal, ecotone and reservoir (littoral-pelagic zone in two different types of lakes (Ceratophyllum-dominated and Potamogeton-dominated lakes; ii to determine whether the contact zone waters differ in hydrochemical and biological terms from the waters of the canal and the open water zone; iii and to evaluate the influence of particular macro-habitats (canal, canal/reservoir, littoral and pelagic zone on the interactions between components of the planktonic food web. We studied four shallow, eutrophic lakes in Polesie Lubelskie (eastern Poland. The highest diversity and abundance of microorganisms and crustaceans were observed in the canal-reservoir contact zone, while the lowest values were noted in the pelagic zone. Hence, the contact zone in the investigated lakes could fulfil the function of an ecotone, distinguished by a significant increase in biodiversity, abundance, and species specificity of micro- and macroorganisms. Weak relations between food web components were found in the Ceratophyllum-dominated lakes, where environmental variables explained the bulk of the total variance in plankton abundance, whereas in the Potamogeton-dominated lakes, where environmental variables had a minor role in the total variance in plankton abundance, strong predator-prey relations were noted. Spatial structure of habitats proved to be another important factor for relationships between food web components, as our study indicated that habitat complexity can reduce negative correlations between food web components. Our study

  13. Inorganic and organic ground-water chemistry in the Canal Creek area of Aberdeen Proving Ground, Maryland

    Science.gov (United States)

    Lorah, M.M.; Vroblesky, D.A.

    1989-01-01

    Groundwater chemical data were collected from November 1986 through April 1987 in the first phase of a 5-year study to assess the possibility of groundwater contamination in the Canal Creek area of Aberdeen Proving Ground, Maryland. Water samples were collected from 87 observation wells screened in Coastal Plain sediments; 59 samples were collected from the Canal Creek aquifer, 18 from the overlying surficial aquifer, and 10 from the lower confined aquifer. Dissolved solids, chloride, iron, manganese, fluoride, mercury, and chromium are present in concentrations that exceed the Federal maximum contaminant levels for drinking water. Elevated chloride and dissolved-solids concentrations appear to be related from contaminant plumes but also could result from brackish-water intrusion. Excessive concentrations of iron and manganese were the most extensive water quality problems found among the inorganic constituents and are derived from natural dissolution of minerals and oxide coatings in the aquifer sediments. Volatile organic compounds are present in the Canal Creek and surficial aquifers, but samples from the lower confined aquifer do not show any evidence of contamination by inorganic or organic chemicals. The volatile organic contaminants detected in the groundwater and their maximum concentrations (in micrograms/L) include 1,1,2,2- tetrachloroethane (9,000); carbon tetrachloride (480); chloroform (460); 1,1,2-trichloroethane (80); 1,2-dichloroethane (990); 1,1-dichloroethane (3.1); tetrachloroethylene (100); trichloroethylene (1,800); 1,2-trans- dichloroethylene (1,200); 1,1-dichloroethylene (4.4); vinyl chloride (140); benzene (70); and chlorobenzene (39). On the basis of information on past activities in the study area, some sources of the volatile organic compounds include: (1) decontaminants and degreasers; (2) clothing-impregnating operations; (3) the manufacture of impregnite material; (4) the manufacture of tear gas; and (5) fuels used in garages and at

  14. The role of water in unconventional in situ energy resource extraction technologies: Chapter 7 in Food, energy, and water: The chemistry connection

    Science.gov (United States)

    Gallegos, Tanya J.; Bern, Carleton R.; Birdwell, Justin E.; Haines, Seth S.; Engle, Mark A.

    2015-01-01

    Global trends toward developing new energy resources from lower grade, larger tonnage deposits that are not generally accessible using “conventional” extraction methods involve variations of subsurface in situ extraction techniques including in situ oil-shale retorting, hydraulic fracturing of petroleum reservoirs, and in situ recovery (ISR) of uranium. Although these methods are economically feasible and perhaps result in a smaller above-ground land-use footprint, there remain uncertainties regarding potential subsurface impacts to groundwater. This chapter provides an overview of the role of water in these technologies and the opportunities and challenges for water reuse and recycling.

  15. Environmental Chemistry Methods (ECM) Index - M

    Science.gov (United States)

    Laboratories use testing methods to identify pesticides in water and soil. Environmental chemistry methods test soil and water samples to determine the fate of pesticides in the environment. Find methods for chemicals with M as the first character.

  16. Environmental Chemistry Methods (ECM) Index - A

    Science.gov (United States)

    Laboratories use testing methods to identify pesticides in water and soil. Environmental chemistry methods test soil and water samples to determine the fate of pesticides in the environment. Find methods for chemicals with A as the first character.

  17. Development of a model to predict the effect of water chemistry on the acute toxicity of cadmium to Photobacterium phosphoreum.

    Science.gov (United States)

    Qu, Ruijuan; Wang, Xinghao; Liu, Zhengtao; Yan, Zhenguang; Wang, Zunyao

    2013-11-15

    Cadmium (Cd) compounds are widely distributed toxic environmental and industrial pollutants, and they may bring danger to growth and development of aquatic organisms. The effects of Ca(2+) (as CaCl2), Mg(2+) (as MgSO4), K(+) (as KCl), pH and complexants (EDTA, the commercial DOM, and three homemade DOMs) on Cd toxicity to Photobacterium phosphoreum were evaluated in standardized 15 min acute toxicity tests. Increases in Ca(2+) concentration resulted in higher EC50 values, indicating the competition between the two ions for uptake sites at the biotic ligand. Increased waterborne Mg(2+) also reduced Cd toxicity, but to a slightly lesser degree compared with Ca(2+). The overall decline in EC50 data with increasing K(+) in test solutions suggested that Cd toxicity was enhanced at larger K(+) concentration. The toxicity alleviation by H(+) was observed over the tested pH range of 5.0-9.0. Additions of complexing agents into the exposure water reduced Cd bioavailability via complexation of Cd(2+), and complexants from different sources displayed different protective effect. The influence of these toxicity modifying factors was finally incorporated into a model that can predict acute cadmidum toxicity for Photobacterium phosphoreum. After validation with laboratory and natural waters, the developed model could support efforts to improve the ecological relevance of presently applied risk assessment procedures. Copyright © 2013 Elsevier B.V. All rights reserved.

  18. Water-Chemistry Data for Selected Springs, Geysers, and Streams in Yellowstone National Park, Wyoming, 2003-2005

    Science.gov (United States)

    Ball, James W.; McCleskey, R. Blaine; Nordstrom, D. Kirk; Holloway, JoAnn M.

    2008-01-01

    Water analyses are reported for 157 samples collected from numerous hot springs, their overflow drainages, and Lemonade Creek in Yellowstone National Park (YNP) during 2003-2005. Water samples were collected and analyzed for major and trace constituents from ten areas of YNP including Terrace and Beryl Springs in the Gibbon Canyon area, Norris Geyser Basin, the West Nymph Creek thermal area, the area near Nymph Lake, Hazle Lake, and Frying Pan Spring, Lower Geyser Basin, Washburn Hot Springs, Mammoth Hot Springs, Potts Hot Spring Basin, the Sulphur Caldron area, and Lemonade Creek near the Solfatara Trail. These water samples were collected and analyzed as part of research investigations in YNP on arsenic, antimony, and sulfur redox distribution in hot springs and overflow drainages, and the occurrence and distribution of dissolved mercury. Most samples were analyzed for major cations and anions, trace metals, redox species of antimony, arsenic, iron, nitrogen, and sulfur, and isotopes of hydrogen and oxygen. Analyses were performed at the sampling site, in an on-site mobile laboratory vehicle, or later in a U.S. Geological Survey laboratory, depending on stability of the constituent and whether it could be preserved effectively. Water samples were filtered and preserved onsite. Water temperature, specific conductance, pH, Eh (redox potential relative to the Standard Hydrogen Electrode), and dissolved hydrogen sulfide were measured onsite at the time of sampling. Acidity was determined by titration, usually within a few days of sample collection. Alkalinity was determined by titration within 1 to 2 weeks of sample collection. Concentrations of thiosulfate and polythionate were determined as soon as possible (generally minutes to hours after sample collection) by ion chromatography in an on-site mobile laboratory vehicle. Total dissolved-iron and ferrous-iron concentrations often were measured onsite in the mobile laboratory vehicle. Concentrations of dissolved

  19. Water-chemistry data for selected springs, geysers, and streams in Yellowstone National Park, Wyoming, 2006-2008

    Science.gov (United States)

    Ball, James W.; McMleskey, R. Blaine; Nordstrom, D. Kirk

    2010-01-01

    Water analyses are reported for 104 samples collected from numerous thermal and non-thermal features in Yellowstone National Park (YNP) during 2006-2008. Water samples were collected and analyzed for major and trace constituents from 10 areas of YNP including Apollinaris Spring and Nymphy Creek along the Norris-Mammoth corridor, Beryl Spring in Gibbon Canyon, Norris Geyser Basin, Lower Geyser Basin, Crater Hills, the Geyser Springs Group, Nez Perce Creek, Rabbit Creek, the Mud Volcano area, and Washburn Hot Springs. These water samples were collected and analyzed as part of research investigations in YNP on arsenic, antimony, iron, nitrogen, and sulfur redox species in hot springs and overflow drainages, and the occurrence and distribution of dissolved mercury. Most samples were analyzed for major cations and anions, trace metals, redox species of antimony, arsenic, iron, nitrogen, and sulfur, and isotopes of hydrogen and oxygen. Analyses were performed at the sampling site, in an on-site mobile laboratory vehicle, or later in a U.S. Geological Survey laboratory, depending on stability of the constituent and whether it could be preserved effectively. Water samples were filtered and preserved on-site. Water temperature, specific conductance, pH, emf (electromotive force or electrical potential), and dissolved hydrogen sulfide were measured on-site at the time of sampling. Dissolved hydrogen sulfide was measured a few to several hours after sample collection by ion-specific electrode on samples preserved on-site. Acidity was determined by titration, usually within a few days of sample collection. Alkalinity was determined by titration within 1 to 2 weeks of sample collection. Concentrations of thiosulfate and polythionate were determined as soon as possible (generally a few to several hours after sample collection) by ion chromatography in an on-site mobile laboratory vehicle. Total dissolved iron and ferrous iron concentrations often were measured on-site in the

  20. Master schedule for CY-1981 Hanford environmental surveillance routine program

    Energy Technology Data Exchange (ETDEWEB)

    Blumer, P.J.; Sula, M.J.; Eddy, P.A.

    1980-12-01

    The current schedule of data collection for the routine environmental surveillance program at the Hanford Site is provided. Questions about specific entries should be referred to the authors since modifications to the schedule are made during the year and special areas of study, usually of short duration, are not scheduled. The environmental surveillance program objectives are to evaluate the levels of radioactive and nonradioactive pollutants in the Hanford environs, as required in Manual Chapter 0513, and to monitor Hanford operations for compliance with applicable environmental criteria given in Manual Chapter 0524 and Washington State Water Quality Standards. Air quality data obtained in a separate program are also reported. The collection schedule for potable water is shown but it is not part of the routine environmental surveillance program. Schedules are presented for the following subjects: air, Columbia River, sanitary water, surface water, ground water, foodstuffs, wildlife, soil and vegetation, external radiation measurement, portable instrument surveys, and surveillance of waste disposal sites. (JGB)

  1. Chemistry 300. Administration Manual for Supervising Teachers, Provincial Examination, Answer Key--Multiple-Choice and Written-Answer Questions, and Provincial Summary Report = Chimie 300. Guide d'administration a l'intention des surveillants d'examen, Examen provincial, Cle de correction--Questions choix multiple et Questions responses ouvertes, et Rapport sommaire provincial.

    Science.gov (United States)

    Manitoba Dept. of Education and Training, Winnipeg.

    This collection of manuals contains the Manitoba Provincial Chemistry Examination for students seeking credit in Senior 4 Chemistry (Chemistry 300) and instructions for its use and grading. The examination is based on the Core Topics of the Senior 4 Chemistry course and accounts for 30% of the student's final grade in the course. The examination…

  2. Scale-dependent effects of land cover on water physico-chemistry and diatom-based metrics in a major river system, the Adour-Garonne basin (South Western France)

    Energy Technology Data Exchange (ETDEWEB)

    Tudesque, Loïc, E-mail: loic.tudesque@univ-tlse3.fr [CNRS, Université Paul Sabatier, ENFA, UMR5174 EDB (Laboratoire Évolution and Diversité Biologique), 118 route de Narbonne, F-31062 Toulouse (France); Université Toulouse 3 Paul Sabatier, CNRS, UMR5174 EDB, F-31062 Toulouse (France); Tisseuil, Clément [CNRS, Université Paul Sabatier, ENFA, UMR5174 EDB (Laboratoire Évolution and Diversité Biologique), 118 route de Narbonne, F-31062 Toulouse (France); Université Toulouse 3 Paul Sabatier, CNRS, UMR5174 EDB, F-31062 Toulouse (France); Lek, Sovan, E-mail: sovan.lek@univ-tlse3.fr [CNRS, Université Paul Sabatier, ENFA, UMR5174 EDB (Laboratoire Évolution and Diversité Biologique), 118 route de Narbonne, F-31062 Toulouse (France); Université Toulouse 3 Paul Sabatier, CNRS, UMR5174 EDB, F-31062 Toulouse (France)

    2014-01-01

    The scale dependence of ecological phenomena remains a central issue in ecology. Particularly in aquatic ecology, the consideration of the accurate spatial scale in assessing the effects of landscape factors on stream condition is critical. In this context, our study aimed at assessing the relationships between multi-spatial scale land cover patterns and a variety of water quality and diatom metrics measured at the stream reach level. This investigation was conducted in a major European river system, the Adour-Garonne river basin, characterized by a wide range of ecological conditions. Redundancy analysis (RDA) and variance partitioning techniques were used to disentangle the different relationships between land cover, water-chemistry and diatom metrics. Our results revealed a top-down “cascade effect” indirectly linking diatom metrics to land cover patterns through water physico-chemistry, which occurred at the largest spatial scales. In general, the strength of the relationships between land cover, physico-chemistry, and diatoms was shown to increase with the spatial scale, from the local to the basin scale, emphasizing the importance of continuous processes of accumulation throughout the river gradient. Unexpectedly, we established that the influence of land cover on the diatom metric was of primary importance both at the basin and local scale, as a result of discontinuous but not necessarily antagonist processes. The most detailed spatial grain of the Corine land cover classification appeared as the most relevant spatial grain to relate land cover to water chemistry and diatoms. Our findings provide suitable information to improve the implementation of effective diatom-based monitoring programs, especially within the scope of the European Water Framework Directive. - Highlights: •The spatial scale dependence of the “cascade effect” in a river system has been demonstrated. •The stren