Science.gov

Sample records for addition water samples

  1. Percent recoveries of anthropogenic organic compounds with and without the addition of ascorbic acid to preserve finished-water samples containing free chlorine, 2004-10

    USGS Publications Warehouse

    Valder, Joshua F.; Delzer, Gregory C.; Bender, David A.; Price, Curtis V.

    2011-01-01

    This report presents finished-water matrix-spike recoveries of 270 anthropogenic organic compounds with and without the addition of ascorbic acid to preserve water samples containing free chlorine. Percent recoveries were calculated using analytical results from a study conducted during 2004-10 for the National Water-Quality Assessment (NAWQA) Program of the U.S. Geological Survey (USGS). The study was intended to characterize the effect of quenching on finished-water matrix-spike recoveries and to better understand the potential oxidation and transformation of 270 anthropogenic organic compounds. The anthropogenic organic compounds studied include those on analytical schedules 1433, 2003, 2033, 2060, 2020, and 4024 of the USGS National Water Quality Laboratory. Three types of samples were collected from 34 NAWQA locations across the Nation: (1) quenched finished-water samples (not spiked), (2) quenched finished-water matrix-spike samples, and (3) nonquenched finished-water matrix-spike samples. Percent recoveries of anthropogenic organic compounds in quenched and nonquenched finished-water matrix-spike samples are presented. Comparisons of percent recoveries between quenched and nonquenched spiked samples can be used to show how quenching affects finished-water samples. A maximum of 18 surface-water and 34 groundwater quenched finished-water matrix-spike samples paired with nonquenched finished-water matrix-spike samples were analyzed. Percent recoveries for the study are presented in two ways: (1) finished-water matrix-spike samples supplied by surface-water or groundwater, and (2) by use (or source) group category for surface-water and groundwater supplies. Graphical representations of percent recoveries for the quenched and nonquenched finished-water matrix-spike samples also are presented.

  2. Study Design and Percent Recoveries of Anthropogenic Organic Compounds With and Without the Addition of Ascorbic Acid to Preserve Water Samples Containing Free Chlorine, 2004-06

    USGS Publications Warehouse

    Valder, Joshua F.; Delzer, Gregory C.; Price, Curtis V.; Sandstrom, Mark W.

    2008-01-01

    The National Water-Quality Assessment (NAWQA) Program of the U.S. Geological Survey (USGS) began implementing Source Water-Quality Assessments (SWQAs) in 2002 that focus on characterizing the quality of source water and finished water of aquifers and major rivers used by some of the larger community water systems in the United States. As used for SWQA studies, source water is the raw (ambient) water collected at the supply well prior to water treatment (for ground water) or the raw (ambient) water collected from the river near the intake (for surface water). Finished water is the water that is treated, which typically involves, in part, the addition of chlorine or other disinfection chemicals to remove pathogens, and is ready to be delivered to consumers. Finished water is collected before the water enters the distribution system. This report describes the study design and percent recoveries of anthropogenic organic compounds (AOCs) with and without the addition of ascorbic acid to preserve water samples containing free chlorine. The percent recoveries were determined by using analytical results from a laboratory study conducted in 2004 by the USGS's National Water Quality Laboratory (NWQL) and from data collected during 2004-06 for a field study currently (2008) being conducted by the USGS's NAWQA Program. The laboratory study was designed to determine if preserving samples with ascorbic acid (quenching samples) adversely affects analytical performance under controlled conditions. During the laboratory study, eight samples of reagent water were spiked for each of five analytical schedules evaluated. Percent recoveries from these samples were then compared in two ways: (1) four quenched reagent spiked samples analyzed on day 0 were compared with four quenched reagent spiked samples analyzed on day 7 or 14, and (2) the combined eight quenched reagent spiked samples analyzed on day 0, 7, or 14 were compared with eight laboratory reagent spikes (LRSs). Percent

  3. GROUND WATER SAMPLING ISSUES

    EPA Science Inventory

    Obtaining representative ground water samples is important for site assessment and
    remedial performance monitoring objectives. Issues which must be considered prior to initiating a ground-water monitoring program include defining monitoring goals and objectives, sampling point...

  4. The role of methanol addition to water samples in reducing analyte adsorption and matrix effects in liquid chromatography-tandem mass spectrometry.

    PubMed

    Li, Wei; Liu, Yucan; Duan, Jinming; Saint, Christopher P; Mulcahy, Dennis

    2015-04-10

    Liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis coupled simply with water filtering before injection has proven to be a simple, economic and time-saving method for analyzing trace-level organic pollutants in aqueous environments. However, the linearity, precision and detection limits of such methods for late-eluting analytes were found to be much poorer than for early-eluting ones due to adsorption of the analytes in the operating system, such as sample vial, flow path and sample loop, creating problems in quantitative analysis. Addition of methanol (MeOH) into water samples as a modifier was shown to be effective in alleviating or even eliminating the negative effect on signal intensity for the late-eluting analytes and at the same time being able to reduce certain matrix effects for real water samples. Based on the maximum detection signal intensity obtained on desorption of the analytes with MeOH addition, the ratio of the detection signal intensity without addition of MeOH to the maximum intensity can be used to evaluate the effectiveness of methanol addition. Accordingly, the values of <50%, 50-80%, 80-120% could be used to indicate strong, medium and no effects, respectively. Based on this concept, an external matrix-matched calibration method with the addition of MeOH has been successfully established for analyzing fifteen pesticides with diverse physico-chemical properties in surface and groundwater with good linearity (r(2): 0.9929-0.9996), precision (intra-day relative standard deviation (RSD): 1.4-10.7%, inter-day RSD: 1.5-9.4%), accuracy (76.9-126.7%) and low limits of detection (0.003-0.028μg/L).

  5. Enantioselective Michael addition of water.

    PubMed

    Chen, Bi-Shuang; Resch, Verena; Otten, Linda G; Hanefeld, Ulf

    2015-02-09

    The enantioselective Michael addition using water as both nucleophile and solvent has to date proved beyond the ability of synthetic chemists. Herein, the direct, enantioselective Michael addition of water in water to prepare important β-hydroxy carbonyl compounds using whole cells of Rhodococcus strains is described. Good yields and excellent enantioselectivities were achieved with this method. Deuterium labeling studies demonstrate that a Michael hydratase catalyzes the water addition exclusively with anti-stereochemistry.

  6. Enantioselective Michael Addition of Water

    PubMed Central

    Chen, Bi-Shuang; Resch, Verena; Otten, Linda G; Hanefeld, Ulf

    2015-01-01

    The enantioselective Michael addition using water as both nucleophile and solvent has to date proved beyond the ability of synthetic chemists. Herein, the direct, enantioselective Michael addition of water in water to prepare important β-hydroxy carbonyl compounds using whole cells of Rhodococcus strains is described. Good yields and excellent enantioselectivities were achieved with this method. Deuterium labeling studies demonstrate that a Michael hydratase catalyzes the water addition exclusively with anti-stereochemistry. PMID:25529526

  7. Developing Water Sampling Standards

    ERIC Educational Resources Information Center

    Environmental Science and Technology, 1974

    1974-01-01

    Participants in the D-19 symposium on aquatic sampling and measurement for water pollution assessment were informed that determining the extent of waste water stream pollution is not a cut and dry procedure. Topics discussed include field sampling, representative sampling from storm sewers, suggested sampler features and application of improved…

  8. Water Sample Concentrator

    SciTech Connect

    Idaho National Laboratory

    2009-07-21

    Automated portable device that concentrates and packages a sample of suspected contaminated water for safe, efficient transport to a qualified analytical laboratory. This technology will help safeguard against pathogen contamination or chemical and biolog

  9. Water Sample Concentrator

    ScienceCinema

    Idaho National Laboratory

    2016-07-12

    Automated portable device that concentrates and packages a sample of suspected contaminated water for safe, efficient transport to a qualified analytical laboratory. This technology will help safeguard against pathogen contamination or chemical and biolog

  10. Water based drilling mud additive

    SciTech Connect

    McCrary, J.L.

    1983-12-13

    A water based fluid additive useful in drilling mud used during drilling of an oil or gas well is disclosed, produced by reacting water at temperatures between 210/sup 0/-280/sup 0/ F. with a mixture comprising in percent by weight: gilsonite 25-30%, tannin 7-15%, lignite 25-35%, sulfonating compound 15-25%, water soluble base compound 5-15%, methylene-yielding compound 1-5%, and then removing substantially all of the remaining water to produce a dried product.

  11. Water sample filtration unit

    USGS Publications Warehouse

    Skougstad, M.W.; Scarbro, G.F.

    1968-01-01

    A readily portable, all plastic, pressure filtration unit is described which greatly facilitates rapid micropore membrane field filtration of up to several liters of water with a minimum risk of inorganic chemical alteration or contamination of the sample. The unit accommodates standard 10.2-cm. (4-inch) diameter filters. The storage and carrying case serves as a convenient filter stand for both field and laboratory use.

  12. Capillary electrophoretic separation of humic substances using hydroxyethyl cellulose as a buffer additive and its application to characterization of humic substances in a river water sample.

    PubMed

    Takahashi, Toru; Kawana, Jun; Hoshino, Hitoshi

    2009-01-01

    We have developed a concise tool for the investigation of the transition of humic substances in environmental water. The separation of water-soluble humic substances was achieved rapidly and effectively by capillary electrophoresis using a polyacrylamide-coated capillary and a phosphate electrophoretic buffer solution (pH 7.0) containing hydroxyethyl cellulose. The separation mechanism was assessed using the ultrafiltration technique. The effect of the complexation of humic substances with metal ions was studied by using the proposed method. When Fe(III) ions or EDTA was added to the sample solution of fulvic acid, a distinct change in the electropherogram pattern based on the conformational change of fulvic acid was observed. The successful application of the proposed method to the characterization of humic substances in a river water sample was also demonstrated.

  13. Considerations in sampling of water.

    PubMed

    Ramsey, Charles A

    2015-01-01

    Sampling water is no different than sampling any other media. It starts with the development of Sample Quality Criteria, understanding of material properties, then application of the Theory of Sampling. The main difference with sampling water as opposed to solids is the material properties. This paper addresses some of the material properties and consequences of those properties for the development of the sampling protocols. Two properties that must be addressed for water are the temporal nature and the inclusion of suspended solids. Examples are provided for three specific water sampling scenarios which may have application to other water sampling scenarios.

  14. 7 CFR 27.25 - Additional samples of cotton; drawing.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 2 2014-01-01 2014-01-01 false Additional samples of cotton; drawing. 27.25 Section... CONTAINER REGULATIONS COTTON CLASSIFICATION UNDER COTTON FUTURES LEGISLATION Regulations Inspection and Samples § 27.25 Additional samples of cotton; drawing. In addition to the samples hereinbefore...

  15. 7 CFR 27.25 - Additional samples of cotton; drawing.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 2 2012-01-01 2012-01-01 false Additional samples of cotton; drawing. 27.25 Section... CONTAINER REGULATIONS COTTON CLASSIFICATION UNDER COTTON FUTURES LEGISLATION Regulations Inspection and Samples § 27.25 Additional samples of cotton; drawing. In addition to the samples hereinbefore...

  16. 7 CFR 27.25 - Additional samples of cotton; drawing.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 2 2011-01-01 2011-01-01 false Additional samples of cotton; drawing. 27.25 Section... CONTAINER REGULATIONS COTTON CLASSIFICATION UNDER COTTON FUTURES LEGISLATION Regulations Inspection and Samples § 27.25 Additional samples of cotton; drawing. In addition to the samples hereinbefore...

  17. 7 CFR 27.25 - Additional samples of cotton; drawing.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Additional samples of cotton; drawing. 27.25 Section... CONTAINER REGULATIONS COTTON CLASSIFICATION UNDER COTTON FUTURES LEGISLATION Regulations Inspection and Samples § 27.25 Additional samples of cotton; drawing. In addition to the samples hereinbefore...

  18. 7 CFR 27.25 - Additional samples of cotton; drawing.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 2 2013-01-01 2013-01-01 false Additional samples of cotton; drawing. 27.25 Section... CONTAINER REGULATIONS COTTON CLASSIFICATION UNDER COTTON FUTURES LEGISLATION Regulations Inspection and Samples § 27.25 Additional samples of cotton; drawing. In addition to the samples hereinbefore...

  19. 21 CFR 71.4 - Samples; additional information.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 1 2013-04-01 2013-04-01 false Samples; additional information. 71.4 Section 71.4 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL COLOR... samples of the color additive, articles used as components thereof, or of the food, drug, or cosmetic...

  20. 21 CFR 71.4 - Samples; additional information.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 1 2012-04-01 2012-04-01 false Samples; additional information. 71.4 Section 71.4 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL COLOR... samples of the color additive, articles used as components thereof, or of the food, drug, or cosmetic...

  1. Water addition, evaporation and water holding capacity of poultry litter.

    PubMed

    Dunlop, Mark W; Blackall, Patrick J; Stuetz, Richard M

    2015-12-15

    Litter moisture content has been related to ammonia, dust and odour emissions as well as bird health and welfare. Improved understanding of the water holding properties of poultry litter as well as water additions to litter and evaporation from litter will contribute to improved litter moisture management during the meat chicken grow-out. The purpose of this paper is to demonstrate how management and environmental conditions over the course of a grow-out affect the volume of water A) applied to litter, B) able to be stored in litter, and C) evaporated from litter on a daily basis. The same unit of measurement has been used to enable direct comparison-litres of water per square metre of poultry shed floor area, L/m(2), assuming a litter depth of 5cm. An equation was developed to estimate the amount of water added to litter from bird excretion and drinking spillage, which are sources of regular water application to the litter. Using this equation showed that water applied to litter from these sources changes over the course of a grow-out, and can be as much as 3.2L/m(2)/day. Over a 56day grow-out, the total quantity of water added to the litter was estimated to be 104L/m(2). Litter porosity, water holding capacity and water evaporation rates from litter were measured experimentally. Litter porosity decreased and water holding capacity increased over the course of a grow-out due to manure addition. Water evaporation rates at 25°C and 50% relative humidity ranged from 0.5 to 10L/m(2)/day. Evaporation rates increased with litter moisture content and air speed. Maintaining dry litter at the peak of a grow-out is likely to be challenging because evaporation rates from dry litter may be insufficient to remove the quantity of water added to the litter on a daily basis.

  2. ADVANCES IN GROUND WATER SAMPLING PROCEDURES

    EPA Science Inventory

    Obtaining representative ground water samples is important for site assessment and remedial performance monitoring objectives. Issues which must be considered prior to initiating a ground-water monitoring program include defining monitoring goals and objectives, sampling point...

  3. Ocean Surface Water Sampling Devices.

    DTIC Science & Technology

    1963-10-01

    also parachuted, captures a volume of the water surface by a cookie cutter action and drew it into a 1-liter Thermos bottle for protection from...effective in landing upright on the water. Faster Dewar samplers without the cookie cutter action but with the same intake method proved about 95

  4. 21 CFR 173.310 - Boiler water additives.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Boiler water additives. 173.310 Section 173.310... CONSUMPTION Specific Usage Additives § 173.310 Boiler water additives. Boiler water additives may be safely... water. Copolymer contains not more than 0.5 percent by weight of acrylic acid monomer (dry weight...

  5. 21 CFR 173.310 - Boiler water additives.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Boiler water additives. 173.310 Section 173.310... CONSUMPTION Specific Usage Additives § 173.310 Boiler water additives. Boiler water additives may be safely... water. Copolymer contains not more than 0.5 percent by weight of acrylic acid monomer (dry weight...

  6. 21 CFR 173.310 - Boiler water additives.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Boiler water additives. 173.310 Section 173.310... CONSUMPTION Specific Usage Additives § 173.310 Boiler water additives. Boiler water additives may be safely... water. Copolymer contains not more than 0.5 percent by weight of acrylic acid monomer (dry weight...

  7. 21 CFR 173.310 - Boiler water additives.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Boiler water additives. 173.310 Section 173.310... CONSUMPTION Specific Usage Additives § 173.310 Boiler water additives. Boiler water additives may be safely... water. Copolymer contains not more than 0.5 percent by weight of acrylic acid monomer (dry weight...

  8. Magnificent Ground Water Connection. [Sample Activities].

    ERIC Educational Resources Information Center

    Environmental Protection Agency, Washington, DC.

    Water conservation and usage is an important concept in science. This document, geared specifically to New England, provides many activities for protecting and discussing ground water situations. Sample activities for grades K-6 include: (1) All the Water in the World; (2) The Case of the Disappearing Water; (3) Deep Subjects--Wells and Ground…

  9. 21 CFR 173.310 - Boiler water additives.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Boiler water additives. 173.310 Section 173.310... Boiler water additives. Boiler water additives may be safely used in the preparation of steam that will... Total not to exceed 1.5 parts per million in boiler feed water. Copolymer contains not more than...

  10. Water evaporation: a transition path sampling study.

    PubMed

    Varilly, Patrick; Chandler, David

    2013-02-07

    We use transition path sampling to study evaporation in the SPC/E model of liquid water. On the basis of thousands of evaporation trajectories, we characterize the members of the transition state ensemble (TSE), which exhibit a liquid-vapor interface with predominantly negative mean curvature at the site of evaporation. We also find that after evaporation is complete, the distributions of translational and angular momenta of the evaporated water are Maxwellian with a temperature equal to that of the liquid. To characterize the evaporation trajectories in their entirety, we find that it suffices to project them onto just two coordinates: the distance of the evaporating molecule to the instantaneous liquid-vapor interface and the velocity of the water along the average interface normal. In this projected space, we find that the TSE is well-captured by a simple model of ballistic escape from a deep potential well, with no additional barrier to evaporation beyond the cohesive strength of the liquid. Equivalently, they are consistent with a near-unity probability for a water molecule impinging upon a liquid droplet to condense. These results agree with previous simulations and with some, but not all, recent experiments.

  11. THE FATE OF FLUOROSILICATE DRINKING WATER ADDITIVES

    EPA Science Inventory

    Periodically, the EPA reexamines its information on regulated drinking water contaminants to deterime if further study is required. Fluoride is one such contaminant undergoing review. The chemical literature indicates that some deficiencies exist in our understanding of the spe...

  12. Additional sampling directions improve detection range of wireless radiofrequency probes

    PubMed Central

    Mada, Marius; Carpenter, T. Adrian; Sawiak, Stephen J.; Williams, Guy B.

    2015-01-01

    Purpose While MRI is enhancing our knowledge about the structure and function of the human brain, subject motion remains a problem in many clinical applications. Recently, the use of wireless radiofrequency markers with three one‐dimensional (1D) navigators for prospective correction was demonstrated. This method is restricted in the range of motion that can be corrected, however, because of limited information in the 1D readouts. Methods Here, the limitation of techniques for disambiguating marker locations was investigated. It was shown that including more sampling directions extends the tracking range for head rotations. The efficiency of trading readout resolution for speed was explored. Results Tracking of head rotations was demonstrated from −19.2 to 34.4°, −2.7 to 10.0°, and −60.9 to 70.9° in the x‐, y‐, and z‐directions, respectively. In the presence of excessive head motion, the deviation of marker estimates from SPM8 was reduced by 17.1% over existing three‐projection methods. This was achieved by using an additional seven directions, extending the time needed for readouts by a factor of 3.3. Much of this increase may be circumvented by reducing resolution, without compromising accuracy. Conclusion Including additional sampling directions extends the range in which markers can be used, for patients who move a lot. Magn Reson Med 76:913–918, 2016. © 2015 The Authors. Magnetic Resonance in Medicine published by Wiley Periodicals, Inc. on behalf of International Society for Magnetic Resonance in Medicine. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. PMID:26418189

  13. Chapter A5. Processing of Water Samples

    USGS Publications Warehouse

    Wilde, Franceska D.; Radtke, Dean B.; Gibs, Jacob; Iwatsubo, Rick T.

    1999-01-01

    The National Field Manual for the Collection of Water-Quality Data (National Field Manual) describes protocols and provides guidelines for U.S. Geological Survey (USGS) personnel who collect data used to assess the quality of the Nation's surface-water and ground-water resources. This chapter addresses methods to be used in processing water samples to be analyzed for inorganic and organic chemical substances, including the bottling of composite, pumped, and bailed samples and subsamples; sample filtration; solid-phase extraction for pesticide analyses; sample preservation; and sample handling and shipping. Each chapter of the National Field Manual is published separately and revised periodically. Newly published and revised chapters will be announced on the USGS Home Page on the World Wide Web under 'New Publications of the U.S. Geological Survey.' The URL for this page is http:/ /water.usgs.gov/lookup/get?newpubs.

  14. Determination of dissolved aluminum in water samples

    USGS Publications Warehouse

    Afifi, A.A.

    1983-01-01

    A technique has been modified for determination of a wide range of concentrations of dissolved aluminum (Al) in water and has been tested. In this technique, aluminum is complexed with 8-hydroxyquinoline at pH 8.3 to minimize interferences, then extracted with methyl isobutyl ketone (MIBK). The extract is analyzed colorimetrically at 395 nm. This technique is used to analyze two forms of monomeric Al, nonlabile (organic complexes) and labile (free, Al, Al sulfate, fluoride and hydroxide complexes). A detection limit 2 ug/L is possible with 25-ml samples and 10-ml extracts. The detection limit can be decreased by increasing the volume of the sample and (or) decreasing the volume of the methyl isobutyl ketone extract. The analytical uncertainty of this method is approximately + or - 5 percent. The standard addition technique provides a recovery test for this technique and ensures precision in samples of low Al concentrations. The average percentage recovery of the added Al plus the amount originally present was 99 percent. Data obtained from analyses of filtered standard solutions indicated that Al is adsorbed on various types of filters. However, the relationship between Al concentrations and adsorption remains linear. A test on standard solutions also indicated that Al is not adsorbed on nitric acid-washed polyethylene and polypropylene bottle wells. (USGS)

  15. Chapter A4. Collection of Water Samples

    USGS Publications Warehouse

    Wilde, Franceska D.

    1999-01-01

    The National Field Manual for the Collection of Water-Quality Data (National Field Manual) describes protocols and provides guidelines for U.S. Geological Survey (USGS) personnel who collect data that are used to assess the quality of the Nation's surface-water and ground-water resources. This chapter addresses preparations and appropriate methods for the collection of surface-water, groundwater, and associated quality-control samples. Among the topics covered are considerations and procedures to prevent sample contamination; establishing site files; instructions for collecting depth-integrated isokinetic and nonisokinetic samples at flowing- and still-water sites; and guidelines for collecting formation water from wells having various types of construction and hydraulic and aquifer characteristics.

  16. Chapter A1. Preparations for Water Sampling

    USGS Publications Warehouse

    Wilde, Franceska D.; Radtke, Dean B.; Gibs, Jacob; Iwatsubo, Rick T.

    1998-01-01

    The National Field Manual for the Collection of Water-Quality Data (National Field Manual) provides guidelines and standard procedures for U.S. Geological Survey (USGS) personnel who collect data used to assess the quality of the Nation's surface-water and ground-water resources. This chapter addresses field-trip preparations, including selection of sample-collection sites for studies of surface-water quality, site reconnaissance and well selection for studies of groundwater quality, and the establishment of electronic files and field files and folders for a sampling site. Each chapter of the National Field Manual is published separately and revised periodically. Newly published and revised chapters are posted on the World Wide Web on the USGS page 'National Field Manual for the Collection of Water-Quality Data.' The URL for this page is http://pubs.water.usgs.gov/twri9A/ (accessed Jan. 31, 2005).

  17. SUPERFUND GROUND WATER ISSUE: GROUND WATER SAMPLING FOR METALS ANALYSES

    EPA Science Inventory

    Filtration of ground-water samples for metals analysis is an issue identified by the Forum as a concern of Superfund decision-makers. Inconsistency in EPA Syperfund cleanup pracices occurs where one EPA Region implements a remedial action based on unfiltered ground-water samples,...

  18. Approach for environmental baseline water sampling

    USGS Publications Warehouse

    Smith, K.S.

    2011-01-01

    Samples collected during the exploration phase of mining represent baseline conditions at the site. As such, they can be very important in forecasting potential environmental impacts should mining proceed, and can become measurements against which future changes are compared. Constituents in stream water draining mined and mineralized areas tend to be geochemically, spatially, and temporally variable, which presents challenges in collecting both exploration and baseline water-quality samples. Because short-term (daily) variations can complicate long-term trends, it is important to consider recent findings concerning geochemical variability of stream-water constituents at short-term timescales in designing sampling plans. Also, adequate water-quality information is key to forecasting potential ecological impacts from mining. Therefore, it is useful to collect baseline water samples adequate tor geochemical and toxicological modeling. This requires complete chemical analyses of dissolved constituents that include major and minor chemical elements as well as physicochemical properties (including pH, specific conductance, dissolved oxygen) and dissolved organic carbon. Applying chemical-equilibrium and appropriate toxicological models to water-quality information leads to an understanding of the speciation, transport, sequestration, bioavailability, and aquatic toxicity of potential contaminants. Insights gained from geochemical and toxicological modeling of water-quality data can be used to design appropriate mitigation and for economic planning for future mining activities.

  19. 10. Water treatment plant, view to S. 1965 addition is ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    10. Water treatment plant, view to S. 1965 addition is in the foreground - Fort Benton Water Treatment Plant, Filtration Plant, Lots 9-13 of Block 7, Fort Benton Original Townsite at Missouri River, Fort Benton, Chouteau County, MT

  20. 52 additional reference population samples for the 55 AISNP panel.

    PubMed

    Pakstis, Andrew J; Haigh, Eva; Cherni, Lotfi; ElGaaied, Amel Ben Ammar; Barton, Alison; Evsanaa, Baigalmaa; Togtokh, Ariunaa; Brissenden, Jane; Roscoe, Janet; Bulbul, Ozlem; Filoglu, Gonul; Gurkan, Cemal; Meiklejohn, Kelly A; Robertson, James M; Li, Cai-Xia; Wei, Yi-Liang; Li, Hui; Soundararajan, Usha; Rajeevan, Haseena; Kidd, Judith R; Kidd, Kenneth K

    2015-11-01

    Ancestry inference for a person using a panel of SNPs depends on the variation of frequencies of those SNPs around the world and the amount of reference data available for calculation/comparison. The Kidd Lab panel of 55 AISNPs has been incorporated in commercial kits by both Life Technologies and Illumina for massively parallel sequencing. Therefore, a larger set of reference populations will be useful for researchers using those kits. We have added reference population allele frequencies for 52 population samples to the 73 previously entered so that there are now allele frequencies publicly available in ALFRED and FROG-kb for a total of 125 population samples.

  1. Benefits of neutral electrolyzed oxidizing water as a drinking water additive for broiler chickens.

    PubMed

    Bügener, E; Kump, A Wilms-Schulze; Casteel, M; Klein, G

    2014-09-01

    In the wake of discussion about the use of drugs in food-producing farms, it seems to be more and more important to search for alternatives and supportive measures to improve health. In this field trial, the influence of electrolyzed oxidizing (EO) water on water quality, drug consumption, mortality, and performance parameters such as BW and feed conversion rate was investigated on 2 broiler farms. At each farm, 3 rearing periods were included in the study. With EO water as the water additive, the total viable cell count and the number of Escherichia coli in drinking water samples were reduced compared with the respective control group. The frequency of treatment days was represented by the number of used daily doses per population and showed lower values in EO-water-treated groups at both farms. Furthermore, the addition of EO water resulted in a lower mortality rate. In terms of analyzed performance parameters, no significant differences were determined. In this study, the use of EO water improved drinking water quality and seemed to reduce the drug use without showing negative effects on performance parameters and mortality rates.

  2. Stereochemistry of enzymatic water addition to C=C bonds.

    PubMed

    Chen, Bi-Shuang; Otten, Linda G; Hanefeld, Ulf

    2015-01-01

    Water addition to carbon-carbon double bonds using hydratases is attracting great interest in biochemistry. Most of the known hydratases are involved in primary metabolism and to a lesser extent in secondary metabolism. New hydratases have recently been added to the toolbox, both from natural sources or artificial metalloenzymes. In order to comprehensively understand how the hydratases are able to catalyse the water addition to carbon-carbon double bonds, this review will highlight the mechanistic and stereochemical studies of the enzymatic water addition to carbon-carbon double bonds, focusing on the syn/anti-addition and stereochemistry of the reaction.

  3. Sampling colloids and colloid-associated contaminants in ground water

    USGS Publications Warehouse

    Backhus, Debera A.; Ryan, Joseph N.; Groher, Daniel M.; MacFarlane, John K.; Gschwend, Philip M.

    1993-01-01

    It has recently been recognized that mobile colloids may affect the transport of contaminants in ground water. To determine the significance of this process, knowledge of both the total mobile load (dissolved + colloid-associated) and the dissolved concentration of a ground-water contaminant must be obtained. Additional information regarding mobile colloid characteristics and concentrations are required to predict accurately the fate and effects of contaminants at sites where significant quantities of colloids are found. To obtain this information, a sampling scheme has been designed and refined to collect mobile colloids while avoiding the inclusion of normally immobile subsurface and well-derived solids. The effectiveness of this sampling protocol was evaluated at a number of contaminated and pristine sites.The sampling results indicated that slow, prolonged pumping of ground water is much more effective at obtaining ground-water samples that represent in situ colloid populations than bailing. Bailed samples from a coal tar-contaminated site contained 10–100 times greater colloid concentrations and up to 750 times greater polycyclic aromatic hydrocarbon concentrations as were detected in slowly pumped samples. The sampling results also indicated that ground-water colloid concentrations should be monitored in the field to determine the adequacy of purging if colloid and colloid-associated contaminants are of interest. To avoid changes in the natural ground-water colloid population through precipitation or coagulation, in situ ground-water chemistry conditions must be preserved during sampling and storage. Samples collected for determination of the total mobile load of colloids and low-solubility contaminants must not be filtered because some mobile colloids are removed by this process. Finally, suggestions that mobile colloids are present in ground water at any particular site should be corroborated with auxiliary data, such as colloid levels in

  4. Ground Water Sampling for Metal Analyses

    EPA Pesticide Factsheets

    Filtration of ground-water samples for metals analysis is an issue identified by the Forum as a concern of Superfund decision-makers. Inconsistency in EPA Superfund cleanup ractices occurs where one EPA Region implements a remedial action based on...

  5. Reliability of chemical analyses of water samples

    SciTech Connect

    Beardon, R.

    1989-11-01

    Ground-water quality investigations require reliable chemical analyses of water samples. Unfortunately, laboratory analytical results are often unreliable. The Uranium Mill Tailings Remedial Action (UMTRA) Project`s solution to this problem was to establish a two phase quality assurance program for the analysis of water samples. In the first phase, eight laboratories analyzed three solutions of known composition. The analytical accuracy of each laboratory was ranked and three laboratories were awarded contracts. The second phase consists of on-going monitoring of the reliability of the selected laboratories. The following conclusions are based on two years experience with the UMTRA Project`s Quality Assurance Program. The reliability of laboratory analyses should not be taken for granted. Analytical reliability may be independent of the prices charged by laboratories. Quality assurance programs benefit both the customer and the laboratory.

  6. Reduction of hexavalent chromium in water samples acidified for preservation

    USGS Publications Warehouse

    Stollenwerk, K.G.; Grove, D.B.

    1985-01-01

    Reduction of hexavalent chromium, Cr(VI), in water samples, preserved by standard techniques, was investigated. The standard preservation technique for water samples that are to be analyzed for Cr(VI) consists of filtration through a 0.45-??m membrane, acidification to a pH < 2, and storage in plastic bottles. Batch experiments were conducted to evaluate the effect of H+ concentration, NO2, temperature, and dissolved organic carbon (DOC) on the reduction of Cr(VI) to Cr(III). The rate of reduction of Cr(VI) to Cr(III) increased with increasing NO2, DOC, H+, and temperature. Reduction of Cr(VI) by organic matter occurred in some samples even though the samples were unacidified. Reduction of Cr(VI) is inhibited to an extent by storing the sample at 4??C. Stability of Cr(VI) in water is variable and depends on the other constituents present in the sample. Water samples collected for the determination of Cr(VI) should be filtered (0.45-??m membrane), refrigerated, and analyzed as quickly as possible. Water samples should not be acidified. Measurement of total Cr in addition to Cr(VI) can serve as a check for Cr(VI) reduction. If total Cr is greater than Cr(VI), the possibility that Cr(VI) reduction has occurred needs to be considered.The rate of reduction of Cr(VI) to Cr(III) increased with increasing NO//2, DOC, H** plus , and temperature. Reduction of Cr(VI) by organic matter occurred in some samples even though the samples were unacidified. Reduction of Cr(VI) is inhibited to an extent by storing the sample at 4 degree C. Stability of Cr(VI) in water is variable and depends on the other constituents present in the sample. Water samples collected for the determination of Cr(VI) should be filtered (0. 45- mu m membrane), refrigerated, and analyzed as quickly as possible. Water samples should not be acidified. Measurement of total Cr in addition to Cr(VI) can serve as a check for Cr(VI) reduction. If total Cr is greater than Cr(VI), the possibility that Cr

  7. Ground Water Sampling at ISCO Sites - Residual Oxidant Impact on Sample Quality and Sample Preservation Guideline

    EPA Science Inventory

    In-situ chemical oxidation (ISCO) involves the delivery of a chemical oxidant into the subsurface where oxidative reactions transform ground water contaminants into less toxic or harmless byproducts. Due to oxidant persistence, ground water samples collected at hazardous waste si...

  8. Effect of water on overbased sulfonate engine oil additives.

    PubMed

    Tavacoli, J W; Dowding, P J; Steytler, D C; Barnes, D J; Routh, A F

    2008-04-15

    The presence and effect of water on calcium carbonate nanoparticles used in engine additives, stabilized with a sulfonate surfactant, is investigated using small-angle neutron scattering, dynamic light scattering, Fourier transform infrared spectroscopy, and rheometry. These techniques provide complementary data that suggests the formation of a layer of water around the core of the particles ensuring continued colloidal stability yet increasing the dispersion viscosity. Through the use of small-angle neutron scattering, the dimensions of this layer have been quantified to effectively one or two water molecules in thickness. The lack of a significant electrostatic repulsion is evidence that the water layer is insufficient to cause major dissociation of surface ions.

  9. Additives for Water Mist Fire Suppression Systems: A Review

    DTIC Science & Technology

    2012-11-01

    this. Water mist produces no acid gases and therefore can be discharged in a space where persons are present. It consists of small water droplets...investigated include film forming additives for Class B fires (generally fluorinated surfactants), alkali metals salts, transition metal chlorides, sulphates ...et portatif sur les navires militaires continue de croître pour plusieurs raisons. Le brouillard d’eau ne contient pas de gaz acides et, par

  10. Construction Site Storm Water Sampling California's New Construction Sampling and Analysis Requirements

    SciTech Connect

    Forrest, C.L.; Mathews, S.

    2002-04-02

    The California State Water Resources Control Board (State Board) originally issued a National Pollutant Discharge System (NPDES) permit for storm water discharges associated with construction activities in 1992. This NPDES permit was issued as a general permit, applicable throughout the state (with certain exceptions). The general construction permit was made site-specific by a discharger-developed Storm Water Pollution Prevention Plan (SWPPP). As with most NPDES construction storm water permits, monitoring requirements were limited to inspections. Sampling and analysis of discharges was not specifically required, but a Regional Water Quality Control Board (Regional Board) could require additional monitoring. In 1999, the State -Board revised and reissued its construction general permit. While the 1999 permit significantly enhanced the erosion and sediment control descriptions and requirements, and expanded the inspection program, sampling and analysis was still not required. Environmental advocacy groups took exception to the absence of sampling requirements and sought relief in court to add sampling and analysis. In 2001, the State Board in response to the court order adopted a resolution requiring sampling and analysis of construction site runoff under two conditions. Turbidity and/or sediment sampling is required when construction site runoff enters water bodies determined to impaired for sediment or turbidity. Sampling for non-visible pollutants is required when construction operations expose materials to storm water. Sampling construction site runoff is relatively new concept for NPDES permits. Only a few permits throughout the country require sampling and analysis for sediment-related pollutants, and California is one of the only permitting entities to require sampling for non-visible pollutants in construction site runoff. The added complexity of sampling runoff requires construction operators and erosion and sediment control professionals to expand their

  11. Terahertz-dependent evaluation of water content in high-water-cut crude oil using additive-manufactured samplers

    NASA Astrophysics Data System (ADS)

    Guan, LiMei; Zhan, HongLei; Miao, XinYang; Zhu, Jing; Zhao, Kun

    2017-04-01

    The evaluation of water content in crude oil is of significance to petroleum exploration and transportation. Terahertz (THz) waves are sensitive to fluctuations in the dipole moment of water. However, due to the strong absorption of water in the THz range, it is difficult for the THz spectrum to determine high water content with the common sampler. In this research, micron-grade samplers for THz detection were designed and manufactured using additive manufacturing (AM) technology. Oil-water mixtures with water content from 1.8% to 90.6% were measured with the THz-TDS system using sample cells. In addition, a detailed analysis was performed of the relationships among THz parameters such as signal peak, time delay, and refractive index as well as absorption coefficient and high water content (>60%). Results suggest that the combination of THz spectroscopy and AM technique is effective for water content evaluation in crude oil and can be further applied in the petroleum industry.

  12. Continuous water sampling and water analysis in estuaries

    USGS Publications Warehouse

    Schemel, L.E.; Dedini, L.A.

    1982-01-01

    Salinity, temperature, light transmission, oxygen saturation, pH, pCO2, chlorophyll a fluorescence, and the concentrations of nitrate, nitrite, dissolved silica, orthophosphate, and ammonia are continuously measured with a system designed primarily for estuarine studies. Near-surface water (2-m depth) is sampled continuously while the vessel is underway; on station, water to depths of 100 m is sampled with a submersible pump. The system is comprised of commercially available instruments, equipment, and components, and of specialized items designed and fabricated by the authors. Data are read from digital displays, analog strip-chart recorders, and a teletype printout, and can be logged in disc storage for subsequent plotting. Data records made in San Francisco Bay illustrate physical, biological, and chemical estuarine processes, such as mixing and phytoplankton net production. The system resolves large- and small-scale events, which contributes to its reliability and usefulness.

  13. A simple supported liquid hollow fiber membrane microextraction for sample preparation of trihalomethanes in water samples.

    PubMed

    Vora-adisak, Narongchai; Varanusupakul, Pakorn

    2006-07-21

    A simple and efficient liquid-phase microextraction (LPME) technique using a supported liquid hollow fiber membrane, in conjunction with gas chromatography-electron capture detector has been developed for extraction and determination of trihalomethanes (THMs) in water samples. THMs were extracted from water samples through an organic extracting solvent impregnated in the pores and filled inside the porous hollow fiber membrane. Our simple conditions were conducted at 35 degrees C with no stirring and no salt addition in order to minimize sample preparation steps. Parameters such as types of hollow fiber membranes, extracting solvents and extraction time were studied and optimized. The method exhibited enrichment factors ranged from 28- to 62-fold within 30 min extraction time. The linearity of the method ranged from 0.2 to 100 microg l(-1). The limits of detection were in the low microg l(-1) level, ranging between 0.01 and 0.2 microg l(-1). The recoveries of spiked THMs at 5 microg l(-1) in water were between 98 and 105% with relative standard deviations (RSDs) less than 4%. Furthermore, the method was applied for determination of THMs in drinking water and tap water samples was reported.

  14. Siting analyses for water quality sampling in a catchment.

    PubMed

    Kao, Jehng-Jung; Li, Pei-Hao; Lin, Chin-Lien; Hu, Wen-Hsin

    2008-04-01

    Pollution loads discharged from upstream development or human activities significantly degrade the water quality of a reservoir. The design of an appropriate water quality sampling network is therefore important for detecting potential pollution events and monitoring pollution trends. However, under a limited budgetary constraint, how to site an appropriate number of sampling stations is a challenging task. A previous study proposed a method applying the simulated annealing algorithm to design the sampling network based on three cost factors including the number of reaches, bank length, and subcatchment area. However, these factors are not directly related to the distribution of possible pollution. Thus, this study modified the method by considering three additional factors, i.e. total phosphorus, nitrogen, and sediment loads. The larger the possible load, the higher the probability of a pollution event may occur. The study area was the Derchi reservoir catchment in Taiwan. Pollution loads were derived from the AGNPS model with rainfall intensity estimated using the Thiessen method. Analyses for a network with various numbers of sampling sites were implemented. The results obtained based on varied cost factors were compared and discussed. With the three additional factors, the chosen sampling network is expected to properly detect pollution events and monitor pollution distribution and temporal trends.

  15. Effects of water addition on soil arthropods and soil characteristics in a precipitation-limited environment

    NASA Astrophysics Data System (ADS)

    Chikoski, Jennifer M.; Ferguson, Steven H.; Meyer, Lense

    2006-09-01

    We investigated the effect of water addition and season on soil arthropod abundance and soil characteristics (%C, %N, C:N, moisture, pH). The experimental design consisted of 24 groups of five boxes distributed within a small aspen stand in Saskatchewan, Canada. The boxes depressed the soil to create a habitat with suitable microclimate for soil arthropods, and by overturning boxes we counted soil arthropods during weekly surveys from April to September 1999. Soil samples were collected at two-month intervals and water was added once per week to half of the plots. Of the eleven recognizable taxonomic units identified, only mites (Acari) and springtails (Collembola) responded to water addition by increasing abundance, whereas ants decreased in abundance with water addition. During summer, springtail numbers increased with water addition, whereas pH was a stronger determinant of mite abundance. In autumn, springtails were positively correlated with water and negatively correlated with mites, whereas mite abundance was negatively correlated with increasing C:N ratio, positively correlated to water addition, and negatively correlated with springtail abundance. Although both mite and springtail numbers decreased in autumn with a decrease in soil moisture, mites became more abundant than springtails suggesting a predator-prey (mite-springtail) relationship. Water had a significant effect on both springtails and mites in summer and autumn supporting the assertion that prairie soil communities are water limited.

  16. Handbook for Sampling and Sample Preservation of Water and Wastewater

    DTIC Science & Technology

    1992-05-01

    high water line or outside the manhole to an above ground stake by means of a rope . Place the intake tubing vertically or at such a slope to ensure...upstream. Limit the orientation of the intake 20 degrees on either side of the head-on. Secure the intake by a rope at all times with no drag placed on...Marked cableways and bridges, steel or metallic taps or tag lines are used for width determinations. For details or procedures for depth and width

  17. UMTRA water sampling and analysis plan, Green River, Utah

    SciTech Connect

    Papusch, R.

    1993-12-01

    The purpose of this water sampling and analysis plan (WSAP) is to provide a basis for groundwater and surface water sampling at the Green River Uranium Mill Tailing Remedial Action (UMTRA) Project site. This WSAP identifies and justifies the sampling locations, analytical parameters, detection limits, and sampling frequency for the monitoring locations.

  18. GROUND WATER SAMPLING USING LOW-FLOW TECHNIQUES

    EPA Science Inventory

    Obtaining representative ground water samples is important for site assessment and remedial performance monitoring objectives. The sampling device or method used to collect samples from monitoring or compliance well can significantly impact data quality and reliability. Low-flo...

  19. ACQUISITION OF REPRESENTATIVE GROUND WATER QUALITY SAMPLES FOR METALS

    EPA Science Inventory

    R.S. Kerr Environmental Research Laboratory (RSKERL) personnel have evaluated sampling procedures for the collection of representative, accurate, and reproducible ground water quality samples for metals for the past four years. Intensive sampling research at three different field...

  20. Silicone rubber selection for passive sampling of pesticides in water.

    PubMed

    Martin, A; Margoum, C; Randon, J; Coquery, M

    2016-11-01

    Silicone rubber can extract organic compounds with a broad range of polarities (logKow>2-3) from aqueous samples. Such compounds include substances of major concern in the protection of aquatic ecosystems and human health, e.g. pesticides. Silicone rubbers (SRs) with various characteristics have been successfully used in sorptive methods for water sample extraction in the laboratory (SPME, SBSE), and for passive sampling in aquatic environments. However, only few studies have evaluated variability in organic compound sorption due to the origin of SRs, particularly for pesticides. The aim of this study was to select an SR for the extraction of pesticides from water samples by passive sampling. To this end we measured the impact of seven SR formulations on sorption capacity, defined by the partition coefficient (Ksw). Kinetic experiments and sorption isotherms were performed to determine extraction recovery as a selection criterion for SRs, and pesticide partition coefficients. Very large differences in affinity for pesticides were found between two kinds of SRs: "Polymerized SR kits" and "Manufactured SRs". One SR was chosen among the "Manufactured SRs", and the Ksw values of 21 pesticides were determined, filling a gap in the literature (1.50additional economic and technical factors, we suggest using SR from Goodfellow in future work to reduce the variability of Ksw literature values.

  1. 40 CFR 80.8 - Sampling methods for gasoline, diesel fuel, fuel additives, and renewable fuels.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... fuel, fuel additives, and renewable fuels. 80.8 Section 80.8 Protection of Environment ENVIRONMENTAL... Provisions § 80.8 Sampling methods for gasoline, diesel fuel, fuel additives, and renewable fuels. The..., blendstocks, fuel additives and renewable fuels for purposes of determining compliance with the...

  2. Methods for collection and analysis of water samples

    USGS Publications Warehouse

    Rainwater, Frank Hays; Thatcher, Leland Lincoln

    1960-01-01

    This manual contains methods used by the U.S. Geological Survey to collect, preserve, and analyze water samples. Throughout, the emphasis is on obtaining analytical results that accurately describe the chemical composition of the water in situ. Among the topics discussed are selection of sampling sites, frequency of sampling, field equipment, preservatives and fixatives, analytical techniques of water analysis, and instruments. Seventy-seven laboratory and field procedures are given for determining fifty-three water properties.

  3. Study of Cloud Water Samples Collected over Northern Poland.

    PubMed

    Polkowska, Ż; Błaś, M; Lech, D; Namieśnik, J

    2014-01-01

    The paper gives the results of the first studies on the chemistry of cloud water collected during 3 mo (Aug.-Oct. 2010) in the free atmosphere over the area to the south of the Tri-City (Gdansk-Sopot-Gdynia) conurbation on the Gulf of Gdansk, Poland. Taken from cumulus, stratus, and stratocumulus clouds by means of an aircraft-mounted collector, the water samples were analyzed for the following contaminants: anions (chlorides, fluorides, nitrates, sulfates, and phosphates), cations (lithium, sodium, potassium, ammonium, calcium, and magnesium), and trace metals. In addition, pH values were measured, and the type and composition of suspended particulate matter was determined. We discuss the relationship between the concentration of inorganic ions and the type of cloud from which water was sampled. The chemistry is also likely related to the circulation pattern and inflow of clean air masses from the Baltic Sea. Moreover, a relationship was found between the composition of the samples examined and the location of pollutant emission sources.

  4. Additive for coal water slurry made from weak slurryability coal

    SciTech Connect

    Zi-xiu Zang; Lin Zhang; Xino-an Fu; Long Jiang

    1993-12-31

    Surface treatment of weak slurryability coal and preparation of highly concentrated coal water slurry (CWS) have been investigated using wettability and rheology measurements. By adding 0.5{approximately}10 wt.% (based on coal) pitch during dry milling coal surface became more hydrophobic and the coal could be easily prepared for CWS which had much lower viscosity compared with CWS of the untreated coal. The reasons of this result is high degree of hydrophobic surface of coal particles made surfactant adsorption easier compared with high degree of hydrophilic surface of coal particles. Another important reason in hydrophobic surface impeded the penetration of water into the inner pores of coal particles which resulted in decreasing swelling ability of coal and enhancing the fluidity of CWS. Four different additives have been investigated including three nonionic ethoxylated surfactants and one mixture of anionic surfactants (sodium humate derivative and naphthalenesulfonic acid-HCHO condensate). Both rheological and thixotropic properties showed that nonionic surfactant G2 was the most efficient additive for preparation of highly concentrated CWS. The results of dynamic experiment illustrated that the slurry had good dynamic stability, in other words, the viscosity of the slurry decreased very slowly at constant stir. The pitch treated coal powders were beneficiated coal had much lower viscosity compared with CWS of the unbeneficiated coal.

  5. Measurement of water by oven evaporation using a novel oven design. 2. Water in motor oils and motor oil additives.

    PubMed

    Margolis, Sam A; Vaishnav, Kevin; Sieber, John R

    2004-11-01

    The measurement of water in lubricating oils is important because water accelerates the corrosion of metal parts and bearings in motors. Some of the additives added to lubricating oils to improve their performance react with the Karl Fischer reagent (KFR) causing a positive bias in the water measurement. A new oven evaporation technique for measuring water in oils has been developed that is automated, requires less sample handling, is easily calibrated, and is capable of measuring relatively small mass fractions of water (> or =50 mg/kg sample). A series of motor oils was analyzed with the standard KFR, a reagent that detects interfering substances that reduce iodine, and the aldehyde-ketone reagent that does not detect substances that react with methanol and form water. The oil samples were heated to 107 degrees C and then reheated to 160 degrees C. At both temperatures, material was measured by both KFRs, but only zinc dithiophosphate released sulfur compounds that would react with the reagent that detects interfering substances. Mass fractions of between 20 and 70% of the volatile material released at either temperature were measured with the standard KFR but not with the aldehyde-ketone reagent. These results demonstrate that there are a number of sources of positive bias in the measurement of water in motor oils and that the standard KFR cannot be used to measure water in motor oils and motor oil additives. These results also indicate that some of the material reacts with methanol to form water. Finally, these results suggest that some of the material that is volatile at 160 degrees C and not at 107 degrees C may be water that is physically occluded or may be substances that react with diethyleneglycol monomethylether to produce water.

  6. Sampling trace organic compounds in water: a comparison of a continuous active sampler to continuous passive and discrete sampling methods

    USGS Publications Warehouse

    Coes, Alissa L.; Paretti, Nicholas V.; Foreman, William T.; Iverson, Jana L.; Alvarez, David A.

    2014-01-01

    A continuous active sampling method was compared to continuous passive and discrete sampling methods for the sampling of trace organic compounds (TOCs) in water. Results from each method are compared and contrasted in order to provide information for future investigators to use while selecting appropriate sampling methods for their research. The continuous low-level aquatic monitoring (CLAM) sampler (C.I.Agent® Storm-Water Solutions) is a submersible, low flow-rate sampler, that continuously draws water through solid-phase extraction media. CLAM samplers were deployed at two wastewater-dominated stream field sites in conjunction with the deployment of polar organic chemical integrative samplers (POCIS) and the collection of discrete (grab) water samples. All samples were analyzed for a suite of 69 TOCs. The CLAM and POCIS samples represent time-integrated samples that accumulate the TOCs present in the water over the deployment period (19–23 h for CLAM and 29 days for POCIS); the discrete samples represent only the TOCs present in the water at the time and place of sampling. Non-metric multi-dimensional scaling and cluster analysis were used to examine patterns in both TOC detections and relative concentrations between the three sampling methods. A greater number of TOCs were detected in the CLAM samples than in corresponding discrete and POCIS samples, but TOC concentrations in the CLAM samples were significantly lower than in the discrete and (or) POCIS samples. Thirteen TOCs of varying polarity were detected by all of the three methods. TOC detections and concentrations obtained by the three sampling methods, however, are dependent on multiple factors. This study found that stream discharge, constituent loading, and compound type all affected TOC concentrations detected by each method. In addition, TOC detections and concentrations were affected by the reporting limits, bias, recovery, and performance of each method.

  7. Sampling trace organic compounds in water: a comparison of a continuous active sampler to continuous passive and discrete sampling methods.

    PubMed

    Coes, Alissa L; Paretti, Nicholas V; Foreman, William T; Iverson, Jana L; Alvarez, David A

    2014-03-01

    A continuous active sampling method was compared to continuous passive and discrete sampling methods for the sampling of trace organic compounds (TOCs) in water. Results from each method are compared and contrasted in order to provide information for future investigators to use while selecting appropriate sampling methods for their research. The continuous low-level aquatic monitoring (CLAM) sampler (C.I.Agent® Storm-Water Solutions) is a submersible, low flow-rate sampler, that continuously draws water through solid-phase extraction media. CLAM samplers were deployed at two wastewater-dominated stream field sites in conjunction with the deployment of polar organic chemical integrative samplers (POCIS) and the collection of discrete (grab) water samples. All samples were analyzed for a suite of 69 TOCs. The CLAM and POCIS samples represent time-integrated samples that accumulate the TOCs present in the water over the deployment period (19-23 h for CLAM and 29 days for POCIS); the discrete samples represent only the TOCs present in the water at the time and place of sampling. Non-metric multi-dimensional scaling and cluster analysis were used to examine patterns in both TOC detections and relative concentrations between the three sampling methods. A greater number of TOCs were detected in the CLAM samples than in corresponding discrete and POCIS samples, but TOC concentrations in the CLAM samples were significantly lower than in the discrete and (or) POCIS samples. Thirteen TOCs of varying polarity were detected by all of the three methods. TOC detections and concentrations obtained by the three sampling methods, however, are dependent on multiple factors. This study found that stream discharge, constituent loading, and compound type all affected TOC concentrations detected by each method. In addition, TOC detections and concentrations were affected by the reporting limits, bias, recovery, and performance of each method.

  8. LABORATORY ANALYSES: WATER AND ENVIRONMENTAL SAMPLES

    EPA Science Inventory

    To be presented at the Workshop for Improving the Recognition, Investigation, and Reporting of Waterborne Disease Outbreaks Associated with Drinking, Recreational and Other Waters in Nashville, TN, May 29 - June 1, 2007

  9. 49 CFR 199.111 - Retention of samples and additional testing.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... SAFETY DRUG AND ALCOHOL TESTING Drug Testing § 199.111 Retention of samples and additional testing. (a...) Since some analytes may deteriorate during storage, detected levels of the drug below the...

  10. 49 CFR 199.111 - Retention of samples and additional testing.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... SAFETY DRUG AND ALCOHOL TESTING Drug Testing § 199.111 Retention of samples and additional testing. (a...) Since some analytes may deteriorate during storage, detected levels of the drug below the...

  11. Additives

    NASA Technical Reports Server (NTRS)

    Smalheer, C. V.

    1973-01-01

    The chemistry of lubricant additives is discussed to show what the additives are chemically and what functions they perform in the lubrication of various kinds of equipment. Current theories regarding the mode of action of lubricant additives are presented. The additive groups discussed include the following: (1) detergents and dispersants, (2) corrosion inhibitors, (3) antioxidants, (4) viscosity index improvers, (5) pour point depressants, and (6) antifouling agents.

  12. Nano-porous pottery using calcined waste sediment from tap water production as an additive.

    PubMed

    Sangsuk, Supin; Khunthon, Srichalai; Nilpairach, Siriphan

    2010-10-01

    A suspension of sediment from a lagoon in a tap water production plant was collected for this experiment. The suspension was spray dried and calcined at 700 °C for 1 h. After calcining, 30 wt.% of the sediment were mixed with pottery clay. Samples with and without calcined sediment were sintered at 900, 1000 and 1100 °C. The results show that calcined sediment can be used as an additive in pottery clay. The samples with calcined sediment show higher porosity, water absorption and flexural strength, especially for 900 and 1000 °C. At 900 °C, samples with calcined sediment show a porosity of 50% with an average pore size of 68 nm, water absorption of 31% and flexural strength of 12.61 MPa.

  13. UMTRA project water sampling and analysis plan -- Shiprock, New Mexico

    SciTech Connect

    Not Available

    1994-02-01

    Water sampling and analysis plan (WSAP) is required for each U.S. Department of Energy (DOE) Uranium Mill Tailings Remedial Action (UMTRA) Project site to provide a basis for ground water and surface water sampling at disposal and former processing sites. This WSAP identifies and justifies the sampling locations, analytical parameters, detection limits, and sampling frequency for the monitoring stations at the Navaho Reservation in Shiprock, New Mexico, UMTRA Project site. The purposes of the water sampling at Shiprock for fiscal year (FY) 1994 are to (1) collect water quality data at new monitoring locations in order to build a defensible statistical data base, (2) monitor plume movement on the terrace and floodplain, and (3) monitor the impact of alluvial ground water discharge into the San Juan River. The third activity is important because the community of Shiprock withdraws water from the San Juan River directly across from the contaminated alluvial floodplain below the abandoned uranium mill tailings processing site.

  14. Visualizing Water Quality Sampling-Events in Florida

    NASA Astrophysics Data System (ADS)

    Bolt, M. D.

    2015-07-01

    Water quality sampling in Florida is acknowledged to be spatially and temporally variable. The rotational monitoring program that was created to capture data within the state's thousands of miles of coastline and streams, and millions of acres of lakes, reservoirs, and ponds may be partly responsible for inducing the variability as an artifact. Florida's new dissolved-oxygen-standard methodology will require more data to calculate a percent saturation. This additional data requirement's impact can be seen when the new methodology is applied retrospectively to the historical collection. To understand how, where, and when the methodological change could alter the environmental quality narrative of state waters requires addressing induced bias from prior sampling events and behaviors. Here stream and coastal water quality data is explored through several modalities to maximize understanding and communication of the spatiotemporal relationships. Previous methodology and expected-retrospective calculations outside the regulatory framework are found to be significantly different, but dependent on the spatiotemporal perspective. Data visualization is leveraged to demonstrate these differences, their potential impacts on environmental narratives, and to direct further review and analysis.

  15. Micellar electrokinetic chromatographic determination of triazine herbicides in water samples.

    PubMed

    Li, Zhi; Zhang, Shuaihua; Yin, Xiaofang; Wang, Chun; Wang, Zhi

    2014-09-01

    Dispersive liquid-liquid microextraction combined with online sweeping preconcentration in micellar electrokinetic chromatography was developed for the simultaneous determination of five triazine herbicides (atrazine, simazine, propazine, prometon and simetryn) in water samples. Several experimental parameters affecting the extraction efficiencies such as the type and volume of both the extraction and dispersive solvents, the addition of salt to sample solution, the extraction time and the pH of the sample solution were investigated. Under optimum conditions, the linearity of the method was good in the range from 0.33 to 20 ng mL(-1) for simazine, propazine, atrazine and simetryn, and from 0.17 to 20 ng mL(-1) for prometon, respectively. The sensitivity enrichment factors were in the range from 1750 to 2100, depending on the compound. The limit of detection (S/N = 3) ranged from 0.05 to 0.10 ng mL(-1). The developed method was successfully applied to the analysis of the five triazines in river, ground and well waters.

  16. Factors controlling elevated lead concentrations in water samples from aquifer systems in Florida

    SciTech Connect

    Katz, B.G.; Berndt, M.P.; Bullen, T.D.; Hansard, P.

    1999-07-01

    This report presents results of detailed statistical analyses of total and dissolved Pb concentrations in water samples collected from the major aquifer systems in Florida for the FGWQMN [Florida Ground Water Quality Monitoring Network] to determine the influence of anthropogenic factors on elevated Pb concentrations. In addition, Pb isotopic data are presented for water samples collected from a subset of 13 wells in the monitoring network, samples of aquifer material, rainfall, and Pb counterweights. The Pb-isotope data provide a better understanding of the relative contributions of anthropogenic and natural sources of Pb in ground water samples from Florida`s major aquifer systems.

  17. Analysis of uranium concentration in drinking water samples using ICPMS.

    PubMed

    Rani, Asha; Mehra, Rohit; Duggal, Vikas; Balaram, V

    2013-03-01

    Uranium concentration in drinking water samples collected from some areas of Northern Rajasthan has been measured using inductively coupled plasma mass spectrometry. The water samples were taken from hand pumps. The uranium concentration in water samples varies from 2.54-133.0 μg L with a mean value of 38.48 μg L. The uranium concentration in most of the drinking water samples exceeds the safe limit (30 μg L) recommended by the World Health Organization. The annual effective dose associated with drinking water due to uranium concentration is estimated from its annual intake using dosimetric information based on ICRP 72. The resulting value of the annual effective dose from drinking water sources is in the range of 2.11-110.45 μSv. The annual effective dose in one of the samples was found to be greater than WHO-recommended level of 100 μSv y.

  18. Development of Sampling and Preservation Techniques to Retard Chemical and Biological Changes in Water Samples

    DTIC Science & Technology

    1983-06-24

    I/ DRXTH-TE-CR-82182 DEVELOPMENT OF SAMPLING AND PRESERVATION TECHNIQUES TO RETARD CHEMICAL AND BIOLOGICAL CHANGES IN WATER SAMPLES by H Rope H...Changes in Water Samples MRI ProjecL No. 7050-A 7. AUTI4OR(c) S. CONTRACT OR GRANT NUM[ER(.) DAAK1l-8l-C-0007 I. PERFORMING ORGANIZATION NAME ANO...Tetryl; Diphenylamine, DPA; Nitrobenzane, NB; 2,6-Dinitrotoluene, 2,6-DNT; Nitroglycerin, NG; and Picric Acid, PA) in water samples. The samples were

  19. Microbial Condition of Water Samples from Foreign Fuel Storage Facilities

    SciTech Connect

    Berry, C.J.; Fliermans, C.B.; Santo Domingo, J.

    1997-10-30

    In order to assess the microbial condition of foreign nuclear fuel storage facilities, fourteen different water samples were received from facilities outside the United States that have sent spent nuclear fuel to SRS for wet storage. Each water sample was analyzed for microbial content and activity as determined by total bacteria, viable aerobic bacteria, viable anaerobic bacteria, viable sulfate- reducing bacteria, viable acid-producing bacteria and enzyme diversity. The results for each water sample were then compared to other foreign samples and to data from the receiving basin for off- site fuel (RBOF) at SRS.

  20. UMTRA project water sampling and analysis plan, Grand Junction, Colorado

    SciTech Connect

    Not Available

    1994-07-01

    Surface remedial action will be completed at the Grand Junction processing site during the summer of 1994. Results of 1993 water sampling indicate that ground water flow conditions and ground water quality at the processing site have remained relatively constant with time. Uranium concentrations in ground water continue to exceed the maximum concentration limits, providing the best indication of the extent of contaminated ground water. Evaluation of surface water quality of the Colorado River indicate no impact from uranium processing activities. No compliance monitoring at the Cheney disposal site has been proposed because ground water in the Dakota Sandstone (uppermost aquifer) is classified as limited-use (Class 111) and because the disposal cell is hydrogeologically isolated from the uppermost aquifer. The following water sampling and water level monitoring activities are planned for calendar year 1994: (i) Semiannual (early summer and late fall) sampling of six existing monitor wells at the former Grand Junction processing site. Analytical results from this sampling will be used to continue characterizing hydrogeochemical trends in background ground water quality and in the contaminated ground water area resulting from source term (tailings) removal. (ii) Water level monitoring of approximately three proposed monitor wells projected to be installed in the alluvium at the processing site in September 1994. Data loggers will be installed in these wells, and water levels will be electronically monitored six times a day. These long-term, continuous ground water level data will be collected to better understand the relationship between surface and ground water at the site. Water level and water quality data eventually will be used in future ground water modeling to establish boundary conditions in the vicinity of the Grand Junction processing site. Modeling results will be used to help demonstrate and document the potential remedial alternative of natural flushing.

  1. A low cost multi-level sampling device for synchronous aseptic collection of environmental water samples.

    PubMed

    McCormick, Michael L; Banishki, Nikola; Powell, Sarah; Rumack, Amy; Garrett, Jinnie M

    2014-10-01

    We describe a simple device for the aseptic collection of environmental water samples at high spatial resolution to depths of 50m. To demonstrate the utility of this technique we present geochemical and archaeal community data from samples collected throughout the water column of a stratified lake.

  2. UMTRA project water sampling and analysis plan, Riverton, Wyoming

    SciTech Connect

    Not Available

    1994-03-01

    Surface remediation was completed at the former uranium mill site in Riverton, Wyoming, in 1990. Residual radioactive materials (contaminated soil and debris) were removed and disposed of at Union Carbide Corporation`s (Umetco) nearby Gas Hills Title 2 facility. Ground water in the surficial and semiconfined aquifers (known collectively as the `uppermost aquifer`) below the former mill and tailings site has been contaminated. No contamination has been detected in the deeper, confined sandstone aquifer. The contaminant plume extends off site to the south and east. The plume is constrained by surface wetlands and small streams to the east and west of the site and by the Little Wind River to the south. Fifteen monitor wells installed in 1993 were sampled to better define the contaminant plume and to provide additional water quality data for the baseline risk assessment. Samples also were collected from domestic wells in response to a request by the Wyoming Department of Environmental Quality in January 1994. No contamination attributable to the former uranium milling operations have ever been detected in any of the domestic wells used for potable supplies.

  3. Water hyacinth a potential source for value addition: An overview.

    PubMed

    Sindhu, Raveendran; Binod, Parameswaran; Pandey, Ashok; Madhavan, Aravind; Alphonsa, Jose Anju; Vivek, Narisetty; Gnansounou, Edgard; Castro, Eulogio; Faraco, Vincenza

    2017-04-01

    Water hyacinth a fresh water aquatic plant is considered as a noxious weed in many parts of the world since it grows very fast and depletes nutrients and oxygen from water bodies adversely affecting the growth of both plants and animals. Hence conversion of this problematic weed to value added chemicals and fuels helps in the self-sustainability especially for developing countries. The present review discusses the various value added products and fuels which can be produced from water hyacinth, the recent research and developmental activities on the bioconversion of water hyacinth for the production of fuels and value added products as well as its possibilities and challenges in commercialization.

  4. Voltammetric Determination of Ni and Co in Water Samples

    NASA Astrophysics Data System (ADS)

    Herrera-Melian, Jose Alberto; Dona-Rodriguez, Jose Miguel; Hernandez-Brito, Joaquin; Perez Pena, Jesus

    1997-12-01

    Stripping voltammetry has attracted considerable attention for the determination of trace and ultratrace metals. This is mainly due to its high sensitivity and low cost of instrumentation. In adsorptive stripping voltammetry an organometallic complex is formed by the addition of a suitable ligand to the sample. The complex is adsorbed onto the Hg-drop by the application of the proper adsorption potential (more positive than E1/2) and solution stirring. After an adsorption period a cathodic (negative going) potential scan is applied and the metal concentration is calculated by the standard addition method. Nickel is found in natural waters at nM levels and is closely related with phosphates and silicates. Cobalt is a component of vitamin B12 and occurs in natural waters at concentration about 0.1 nM. We propose the voltammetric analysis of these elements by adsorptive stripping voltammetry as an introductory laboratory experiment for advanced chemistry or for chemical or environmental engineering students. The experiment has been proven to be very suitable for the laboratory part of the instrumental analysis course at the University of Las Palmas de Gran Canaria (Spain). In general, about 70% of the students have obtained good agreement (less than 10% of difference) between their results and the expected ones. Two hours is enough for the overall instrumental performance and the preparation of Ni and Co standards.

  5. Decontaminating materials used in ground water sampling devices: Organic contaminants

    SciTech Connect

    Parker, L.V.; Ranney, T.A.

    2000-12-31

    In these studies, the efficiency of various decontamination protocols was tested on small pieces of materials commonly used in ground water sampling devices. Three materials, which ranged in ability to sorb organic solutes, were tested: stainless steel (SS), rigid polyvinyl chloride (PVC), and polytetrafluoroethylene (PTFE). The test pieces were exposed to two aqueous test solutions: One contained three volatile organic compounds (VOCs) and one nitroaromatic compound, and the other contained four pesticides. Also, three types of polymetic tubing were exposed to pesticide solutions. Generally, the contact times were 10 minutes and 24 hours for sorption and desorption. The contaminants were removed from the nonpermeable SS and the less-sorptive rigid PVC test pieces simply by washing with a hot detergent solution and rinsing with hot water. Additional treatment was required for the PTFE test pieces exposed to the VOCs and for the low-density polyethylene (LDPE) tubing exposed to the pesticide test solution. Solvent rinsing did not improve removal of the three VOCs form the PTFE and only marginally improved removal of the residual pesticides from the LDPE. However, a hot water and detergent wash and rinse followed by oven drying at approximately 105 C was effective for removing the VOCs from the PTFE and substantially reduced pesticide contamination from the LDPE.

  6. July 2010 Natural Gas and Produced Water Sampling at the Gasbuggy, New Mexico, Site

    SciTech Connect

    2011-01-01

    Annual natural gas and produced water monitoring was conducted for gas wells adjacent to Section 36, where the Gasbuggy test was conducted, in accordance with the draft Long-Term Surveillance and Maintenance Plan for the Gasbuggy Site, Rio Arriba County, New Mexico. Sampling and analysis was conducted as specified in the Sampling and Analysis Plan for U.S. Department of Energy Office of Legacy Management Sites. (LMS/PLN/S04351, continually updated). Natural gas samples were collected for tritium and carbon-14 analysis. Produced water samples were collected and analyzed for tritium, gamma-emitting radionuclides (by high-resolution gamma spectrometry), gross alpha, and gross beta. An additional water sample was collected from well 29-6 Water Hole for analysis of tritium and gamma-emitting radionuclides. A duplicate produced water sample was collected from well 30-039-21743.

  7. UMTRA water sampling and analysis plan, Tuba City, Arizona. Draft

    SciTech Connect

    Not Available

    1993-09-01

    The purpose of this document is to provide background, guidance, and justification for fiscal year (FY) 1994 water sampling activities for the uranium mil tailings site at Tuba City, Arizona. This sampling and analysis plan will form the basis for groundwater sampling and analysis work orders to be implemented in FY94.

  8. 31. VIEW FROM SOUTHWEST TO CORNER WHERE SAMPLING/CRUSHING ADDITIONS ABUT ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    31. VIEW FROM SOUTHWEST TO CORNER WHERE SAMPLING/CRUSHING ADDITIONS ABUT CRUSHED OXIDIZED ORE BIN. INTACT BARREN SOLUTION TANK VISIBLE IN FRONT OF CRUSHED ORE BIN. - Bald Mountain Gold Mill, Nevada Gulch at head of False Bottom Creek, Lead, Lawrence County, SD

  9. Monitoring of fluoride in water samples using a smartphone.

    PubMed

    Levin, Saurabh; Krishnan, Sunderrajan; Rajkumar, Samuel; Halery, Nischal; Balkunde, Pradeep

    2016-05-01

    In several parts of India, groundwater is the only reliable, year round source for drinking water. Prevention of fluorosis, a chronic disease resulting from excess intake of fluoride, requires the screening of all groundwater sources for fluoride in endemic areas. In this paper, the authors present a field deployable colorimetric analyzer based on an inexpensive smartphone embedded with digital camera for taking photograph of the colored solution as well as an easy-fit, and compact sample chamber (Akvo Caddisfly). Phones marketed by different smartphone makers were used. Commercially available zirconium xylenol orange reagent was used for determining fluoride concentration. A software program was developed to use with the phone for recording and analyzing the RGB color of the picture. Linear range for fluoride estimation was 0-2mgl(-1). Around 200 samples, which consisted of laboratory prepared as well as field samples collected from different locations in Karnataka, India, were tested with Akvo Caddisfly. The results showed a significant positive correlation between Ion Selective Electrode (ISE) method and Akvo Caddisfly (Phones A, B and C), with correlation coefficient ranging between 0.9952 and 1.000. In addition, there was no significant difference in the mean fluoride content values between ISE and Phone B and C except for Phone A. Thus the smartphone method is economical and suited for groundwater fluoride analysis in the field.

  10. Studies of levels of biogenic amines in meat samples in relation to the content of additives.

    PubMed

    Jastrzębska, Aneta; Kowalska, Sylwia; Szłyk, Edward

    2016-01-01

    The impact of meat additives on the concentration of biogenic amines and the quality of meat was studied. Fresh white and red meat samples were fortified with the following food additives: citric and lactic acids, disodium diphosphate, sodium nitrite, sodium metabisulphite, potassium sorbate, sodium chloride, ascorbic acid, α-tocopherol, propyl 3,4,5-trihydroxybenzoate (propyl gallate) and butylated hydroxyanisole. The content of spermine, spermidine, putrescine, cadaverine, histamine, tyramine, tryptamine and 2-phenylethylamine was determined by capillary isotachophoretic methods in meat samples (fresh and fortified) during four days of storage at 4°C. The results were applied to estimate the impact of the tested additives on the formation of biogenic amines in white and red meat. For all tested meats, sodium nitrite, sodium chloride and disodium diphosphate showed the best inhibition. However, cadaverine and putrescine were characterised by the biggest changes in concentration during the storage time of all the additives. Based on the presented data for the content of biogenic amines in meat samples analysed as a function of storage time and additives, we suggest that cadaverine and putrescine have a significant impact on meat quality.

  11. UMTRA project water sampling and analysis plan, Tuba City, Arizona

    SciTech Connect

    1996-02-01

    Planned, routine ground water sampling activities at the U.S. Department of Energy (DOE) Uranium Mill Tailings Remedial Action (UMTRA) Project site in Tuba City, Arizona, are described in the following sections of this water sampling and analysis plan (WSAP). This plan identifies and justifies the sampling locations, analytical parameters, detection limits, and sampling frequency for the stations routinely monitored at the site. The ground water data are used for site characterization and risk assessment. The regulatory basis for routine ground water monitoring at UMTRA Project sites is derived from the U.S. Environmental Protection Agency (EPA) regulations in 40 CFR Part 192 (1994) and the final EPA standards of 1995 (60 FR 2854). Sampling procedures are guided by the UMTRA Project standard operating procedures (SOP) (JEG, n.d.), and the most effective technical approach for the site.

  12. The stability of chlorofluorocarbons (CFCs) in ground-water samples archived in borosilicate ampoules

    USGS Publications Warehouse

    Shapiro, Stephanie Dunkle; Busenberg, Eurybiades; Plummer, L. Niel

    2005-01-01

    The U.S. Geological Survey (USGS) Chlorofluorocarbon (CFC) Laboratory in Reston, Va., has been measuring concentrations of CFCs in ground-water samples since 1989 to estimate the year that a water sample was recharged to a ground-water flow system. The water samples have been collected in flame-sealed borosilicate ampoules. Typically for each site, three samples were analyzed within days to a few months after collection, and additional samples were archived for extended periods of time (up to four years). The stability of CFC concentrations in the archived water samples from the USGS CFC Laboratory was investigated by analyzing the CFC concentrations in archived water samples and comparing them with the CFC concentrations that were obtained soon after the samples were collected. The archived samples selected for analysis were chosen from sites with a wide variety of hydrogeologic and geochemical conditions. For CFC-11 and CFC-12 concentrations, approximately 14% and 10.5%, respectively, of the archived samples were statistically different (both higher and lower) from the concentrations obtained from analyses conducted soon after the sample collection. Most of the extraneous values were attributed to natural variability of CFC concentrations originally in the water discharged from wells, rather than to microbial degradation within the ampoule on storage.

  13. UMTRA project water sampling and analysis plan, Monument Valley, Arizona

    SciTech Connect

    Not Available

    1994-04-01

    The Monument Valley Uranium Mill Tailings Remedial Action (UMTRA) Project site in Cane Valley is a former uranium mill that has undergone surface remediation in the form of tailings and contaminated materials removal. Contaminated materials from the Monument Valley (Arizona) UMTRA Project site have been transported to the Mexican Hat (Utah) UMTRA Project site for consolidation with the Mexican Hat tailings. Tailings removal was completed in February 1994. Three geologic units at the site contain water: the unconsolidated eolian and alluvial deposits (alluvial aquifer), the Shinarump Conglomerate (Shinarump Member), and the De Chelly Sandstone. Water quality analyses indicate the contaminant plume has migrated north of the site and is mainly in the alluvial aquifer. An upward hydraulic gradient in the De Chelly Sandstone provides some protection to that aquifer. This water sampling and analysis plan recommends sampling domestic wells, monitor wells, and surface water in April and September 1994. The purpose of sampling is to continue periodic monitoring for the surface program, evaluate changes to water quality for site characterization, and provide data for the baseline risk assessment. Samples taken in April will be representative of high ground water levels and samples taken in September will be representative of low ground water levels. Filtered and nonfiltered samples will be analyzed for plume indicator parameters and baseline risk assessment parameters.

  14. The influence of compost addition on the water repellency of brownfield soils

    NASA Astrophysics Data System (ADS)

    Whelan, Amii; Kechavarzi, Cedric; Sakrabani, Ruben; Coulon, Frederic; Simmons, Robert; Wu, Guozhong

    2010-05-01

    Compost application to brownfield sites, which can facilitate the stabilisation and remediation of contaminants whilst providing adequate conditions for plant growth, is seen as an opportunity to divert biodegradable wastes from landfill and put degraded land back into productive use. However, although compost application is thought to improve soil hydraulic functioning, there is a lack of information on the impact of large amounts of compost on soil water repellency. Water repellency in soils is attributed to the accumulation of hydrophobic organic compounds released as root exudates, fungal and microbial by-products and decomposition of organic matter. It has also been shown that brownfield soils contaminated with petroleum-derived organic contaminants can exhibit strong water repellency, preventing the rapid infiltration of water and leading potentially to surface run off and erosion of contaminated soil. However, hydrophobic organic contaminants are known to become sequestrated by partitioning into organic matter or diffusing into nano- and micropores, making them less available over time (ageing). The effect of large amounts of organic matter addition through compost application on the water repellency of soils contaminated with petroleum-derived organic contaminants requires further investigation. We characterised the influence of compost addition on water repellency in the laboratory by measuring the Water Drop Penetration Time (WDPT), sorptivity and water repellency index through infiltration experiments on soil samples amended with two composts made with contrasting feedstocks (green waste and predominantly meat waste). The treatments consisted of a sandy loam, a clay loam and a sandy loam contaminated with diesel fuel and aged for 3 years, which were amended with the two composts at a rate equivalent to 750t/ha. In addition core samples collected from a brownfield site, amended with compost at three different rates (250, 500 and 750t/ha) in 2007, were

  15. UMTRA water sampling and analysis plan, Lakeview, Oregon

    SciTech Connect

    Not Available

    1993-09-29

    The purpose of this document is to provide background, guidance, and justification for water sampling activities for the Lakeview, Oregon, Uranium Mill Tailings Remedial Action (UMTRA) processing and disposal sites. This water sampling and analysis plan will form the basis for groundwater sampling and analysis work orders (WSAWO) to be implemented during 1993. Monitoring at the former Lakeview processing site is for characterization purposes and in preparation for the risk assessment, scheduled for the fall of 1993. Compliance monitoring was conducted at the disposal site. Details of the sampling plan are discussed in Section 5.0.

  16. 4. VIEW TO NORTHEAST, SKINNER SALT ROASTERS, SAMPLING BUILDING, WATER ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. VIEW TO NORTHEAST, SKINNER SALT ROASTERS, SAMPLING BUILDING, WATER TOWER, AND OFFICE BUILDING. - Vanadium Corporation of America (VCA) Naturita Mill, 3 miles Northwest of Naturita, between Highway 141 & San Miguel River, Naturita, Montrose County, CO

  17. 10. VIEW TO SOUTHEAST, SAMPLING BUILDING, FOUNDATION, WATER TOWER, AND ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    10. VIEW TO SOUTHEAST, SAMPLING BUILDING, FOUNDATION, WATER TOWER, AND SKINNER SALT ROASTERS. - Vanadium Corporation of America (VCA) Naturita Mill, 3 miles Northwest of Naturita, between Highway 141 & San Miguel River, Naturita, Montrose County, CO

  18. 5. VIEW TO SOUTH, SAMPLING BUILDING AND WATER TOWER. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. VIEW TO SOUTH, SAMPLING BUILDING AND WATER TOWER. - Vanadium Corporation of America (VCA) Naturita Mill, 3 miles Northwest of Naturita, between Highway 141 & San Miguel River, Naturita, Montrose County, CO

  19. Preparation of water samples for carbon-14 dating

    USGS Publications Warehouse

    Feltz, H.R.; Hanshaw, Bruce B.

    1963-01-01

    For most natural water, a large sample is required to provide the 3 grams of carbon needed for a carbon-14 determination. A field procedure for isolating total dissolved-carbonate species is described. Carbon dioxide gas is evolved by adding sulfuric acid to the water sample; the gas is then collected in a sodium hydroxide trap by recycling in a closed system. The trap is then transported to the dating laboratory where the carbon-14 is counted.

  20. ISS Potable Water Sampling and Chemical Analysis Results for 2016

    NASA Technical Reports Server (NTRS)

    Straub, John E., II; Plumlee, Debrah K.; Wallace William T.; Alverson, James T.; Benoit, Mickie J.; Gillispie, Robert L.; Hunter, David; Kuo, Mike; Rutz, Jeffrey A.; Hudson, Edgar K.; Loh, Leslie J.; Gazda, Daniel B.

    2017-01-01

    This paper continues the annual tradition of summarizing at this conference the results of chemical analyses performed on archival potable water samples returned from the International Space Station (ISS). 2016 represented a banner year for life on board the ISS, including the successful conclusion for two crew members of a record one-year mission. Water reclaimed from urine and/or humidity condensate remained the primary source of potable water for the crew members of ISS Expeditions 46-50. The year 2016 was also marked by the end of a long-standing tradition of U.S. sampling and monitoring of Russian Segment potable water sources. Two water samples taken during Expedition 46 in February 2016 and returned on Soyuz 44, represented the final Russian Segment samples to be collected and analyzed by the U.S. side. Although anticipated for 2016, a rise in the total organic carbon (TOC) concentration of the product water from the U.S. water processor assembly due to breakthrough of organic contaminants from the system did not materialize, as evidenced by the onboard TOC analyzer and archive sample results.

  1. RAPID DETERMINATION OF {sup 210} PO IN WATER SAMPLES

    SciTech Connect

    Maxwell, S.

    2013-05-22

    A new rapid method for the determination of {sup 210}Po in water samples has been developed at the Savannah River National Laboratory (SRNL) that can be used for emergency response or routine water analyses. If a radiological dispersive device (RDD) event or a radiological attack associated with drinking water supplies occurs, there will be an urgent need for rapid analyses of water samples, including drinking water, ground water and other water effluents. Current analytical methods for the assay of {sup 210}Po in water samples have typically involved spontaneous auto-deposition of {sup 210}Po onto silver or other metal disks followed by counting by alpha spectrometry. The auto-deposition times range from 90 minutes to 24 hours or more, at times with yields that may be less than desirable. If sample interferences are present, decreased yields and degraded alpha spectrums can occur due to unpredictable thickening in the deposited layer. Separation methods have focused on the use of Sr Resin, often in combination with 210Pb analysis. A new rapid method for {sup 210}Po in water samples has been developed at the Savannah River National Laboratory (SRNL) that utilizes a rapid calcium phosphate co-precipitation method, separation using DGA Resin (N,N,N,N-tetraoctyldiglycolamide extractant-coated resin, Eichrom Technologies or Triskem-International), followed by rapid microprecipitation of {sup 210}Po using bismuth phosphate for counting by alpha spectrometry. This new method can be performed quickly with excellent removal of interferences, high chemical yields and very good alpha peak resolution, eliminating any potential problems with the alpha source preparation for emergency or routine samples. A rapid sequential separation method to separate {sup 210} Po and actinide isotopes was also developed. This new approach, rapid separation with DGA Resin plus microprecipitation for alpha source preparation, is a significant advance in radiochemistry for the rapid

  2. Impact of Oxidant Residuals on Ground Water Samples at ISCO Sites: Recommended Guidelines for Sample Preservation

    EPA Science Inventory

    In-situ chemical oxidation (ISCO) involves the introduction of a chemical oxidant into the subsurface for the purpose of transforming ground water contaminants into less toxic or harmless byproducts. Due to oxidant persistence, ground water samples collected at hazardous waste si...

  3. Superoxygenated Water as an Experimental Sample for NMR Relaxometry

    ERIC Educational Resources Information Center

    Nestle, Nikolaus; Dakkouri, Marwan; Rauscher, Hubert

    2004-01-01

    The increase in NMR relaxation rates as a result of dissolved paramagnetic species on the sample of superoxygenated drinking water is demonstrated. It is concluded that oxygen content in NMR samples is an important issue and can give rise to various problems in the interpretation of both spectroscopic and NMR imaging or relaxation experiments.

  4. ENHANCED DAPI STAINING FOR CRYPTOSPORIDIUM IN WATER SAMPLES

    EPA Science Inventory

    The U.S. Environmental Protection Agency's Method 1623 is used to detect and quantify the presence of {ital Cryptosporidium} spp. oocysts in water. The protocol consists of concentrating a sample, staining this concentrate with a fluorescent antibody, and examining the sample mi...

  5. GROUND WATER PURGING AND SAMPLING METHODS: HISTORY VS. HYSTERIA

    EPA Science Inventory

    It has been over 10 years since the low-flow ground water purging and sampling method was initially reported in the literature. The method grew from the recognition that well purging was necessary to collect representative samples, bailers could not achieve well purging, and high...

  6. Oxygen Isotopic Analyses of Water Extracted from Lunar Samples

    NASA Astrophysics Data System (ADS)

    Nunn Martinez, M.; Thiemens, M. H.

    2014-12-01

    Oxygen exists in lunar materials in distinct phases having unique sources and equilibration histories. The oxygen isotopic composition (δ17O, δ18O) of various components of lunar materials has been studied extensively, but analyses of water in these samples are relatively sparse [1-3]. Samples collected on the lunar surface reflect not only the composition of their source reservoirs but also contributions from asteroidal and cometary impacts, interactions with solar wind and cosmic radiation, among other surface processes. Isotopic characterization of oxygen in lunar water could help resolve the major source of water in the Earth-Moon system by revealing if lunar water is primordial, asteroidal, or cometary in origin [1]. Methods: A lunar rock/soil sample is pumped to high vacuum to remove physisorbed water before heating step-wise to 50, 150, and 1000°C to extract extraterrestrial water without terrestrial contamination. The temperature at which water is evolved is proportional to the strength with which the water is bound in the sample and the relative difficulty of exchanging oxygen atoms in that water. This allows for the isolated extraction of water bound in different phases, which could have different source reservoirs and/or histories, as evidenced by the mass (in)dependence of oxygen compositions. A low blank procedure was developed to accommodate the low water content of lunar material [4]. Results: Oxygen isotopic analyses of lunar water extracted by stepwise heating lunar basalts and breccias with a range of compositions, petrologic types, and surface exposure ages will be presented. The cosmic ray exposure age of these samples varies by two orders of magnitude, and we will consider this in discussing the effects of solar wind and cosmic radiation on the oxygen isotopic composition (Δ17O). I will examine the implications of our water analyses for the composition of the oxygen-bearing reservoir from which that water formed, the effects of surface

  7. UMTRA project water sampling and analysis plan, Mexican Hat, Utah

    SciTech Connect

    Not Available

    1994-04-01

    The Mexican Hat, Utah, Uranium Mill Tailings Remedial Action (UMTRA) Project site is a former uranium mill that is undergoing surface remediation in the form of on-site tailings stabilization. Contaminated surface materials from the Monument Valley, Arizona, UMTRA Project site have been transported to the Mexican Hat site and are being consolidated with the Mexican Hat tailings. The scheduled completion of the tailings disposal cell is August 1995. Water is found in two geologic units at the site: the Halgaito Shale Formation and the Honaker Trail Formation. The tailings rest on the Halgaito Shale, and water contained in that unit is a result of milling activities and, to a lesser extent, water released from the tailings from compaction during remedial action construction of the disposal cell. Water in the Halgaito Shale flows through fractures and discharges at seeps along nearby arroyos. Flow from the seeps will diminish as water drains from the unit. Ground water in the lower unit, the Honaker Trail Formation, is protected from contamination by an upward hydraulic gradient. There are no nearby water supply wells because of widespread poor background ground water quality and quantity, and the San Juan River shows no impacts from the site. This water sampling and analysis plan (WSAP) recommends sampling six seeps and one upgradient monitor well compared in the Honaker Trail Formation. Samples will be taken in April 1994 (representative of high group water levels) and September 1994 (representative of low ground water levels). Analyses will be performed on filtered samples for plume indicator parameters.

  8. Nitrification in lake sediment with addition of drinking water treatment residuals.

    PubMed

    Wang, Changhui; Liu, Juanfeng; Wang, Zhixin; Pei, Yuansheng

    2014-06-01

    Drinking water treatment residuals (WTRs), non-hazardous by-products generated during potable water production, can effectively reduce the lake internal phosphorus (P) loading and improve water quality in lakes. It stands to reason that special attention regarding the beneficial reuse of WTRs should be given not only to the effectiveness of P pollution control, but also to the effects on the migration and transformation of other nutrients (e.g., nitrogen (N)). In this work, based on laboratory enrichment tests, the effects of WTRs addition on nitrification in lake sediment were investigated using batch tests, fluorescence in situ hybridization, quantitative polymerase chain reaction and phylogenetic analysis techniques. The results indicated that WTRs addition had minor effects on the morphologies of AOB and NOB; however, the addition slightly enhanced the sediment nitrification potential from 12.8 to 13.2 μg-N g(-1)-dry sample h(-1) and also increased the ammonia oxidation bacteria (AOB) and nitrite oxidizing bacteria (NOB) abundances, particularly the AOB abundances (P < 0.05), which increased from 1.11 × 10(8) to 1.31 × 10(8) copies g(-1)-dry sample. Moreover, WTRs addition was beneficial to the enrichment of Nitrosomonas and Nitrosospira multiformis and promoted the emergence of a new Nitrospira cluster, causing the increase in AOB and NOB diversities. Further analysis showed that the variations of nitrification in lake sediment after WTRs addition were primarily due to the decrease of bioavailable P, the introduction of new nitrifiers and the increase of favorable carriers for microorganism attachment in sediments. Overall, these results suggested that WTRs reuse for the control of lake internal P loading would also lead to conditions that are beneficial to nitrification.

  9. Chapter A3. Cleaning of Equipment for Water Sampling

    USGS Publications Warehouse

    Wilde, Franceska D.; Radtke, Dean B.; Gibs, Jacob; Iwatsubo, Rick T.

    1998-01-01

    The National Field Manual for the Collection of Water-Quality Data (National Field Manual) describes protocols and provides guidelines for U.S. Geological Survey (USGS) personnel who collect data used to assess the quality of the Nation's surface-water and ground-water resources. Chapter A3 describes procedures for cleaning the equipment used to collect and process samples of surface water and ground water and procedures for assessing the efficacy of the equipment-cleaning process. This chapter is designed for use with the other chapters of this field manual. Each chapter of the National Field Manual is published separately and revised periodically. Newly published and revised chapters will be posted on the USGS page 'National Field Manual for the Collection of Water-Quality Data.' The URL for this page is http://pubs.water.usgs.gov/twri9A/ (accessed September 20, 2004).

  10. Lead (Pb) quantification in potable water samples: implications for regulatory compliance and assessment of human exposure.

    PubMed

    Triantafyllidou, Simoni; Nguyen, Caroline K; Zhang, Yan; Edwards, Marc A

    2013-02-01

    Assessing the health risk from lead (Pb) in potable water requires accurate quantification of the Pb concentration. Under worst-case scenarios of highly contaminated water samples, representative of public health concerns, up to 71-98 % of the total Pb was not quantified if water samples were not mixed thoroughly after standard preservation (i.e., addition of 0.15 % (v/v) HNO(3)). Thorough mixing after standard preservation improved recovery in all samples, but 35-81 % of the total Pb was still un-quantified in some samples. Transfer of samples from one bottle to another also created high errors (40-100 % of the total Pb was un-quantified in transferred samples). Although the United States Environmental Protection Agency's standard protocol avoids most of these errors, certain methods considered EPA-equivalent allow these errors for regulatory compliance sampling. Moreover, routine monitoring for assessment of human Pb exposure in the USA has no standardized protocols for water sample handling and pre-treatment. Overall, while there is no reason to believe that sample handling and pre-treatment dramatically skew regulatory compliance with the US Pb action level, slight variations from one approved protocol to another may cause Pb-in-water health risks to be significantly underestimated, especially for unusual situations of "worst case" individual exposure to highly contaminated water.

  11. On the asymptotic improvement of supervised learning by utilizing additional unlabeled samples - Normal mixture density case

    NASA Technical Reports Server (NTRS)

    Shahshahani, Behzad M.; Landgrebe, David A.

    1992-01-01

    The effect of additional unlabeled samples in improving the supervised learning process is studied in this paper. Three learning processes. supervised, unsupervised, and combined supervised-unsupervised, are compared by studying the asymptotic behavior of the estimates obtained under each process. Upper and lower bounds on the asymptotic covariance matrices are derived. It is shown that under a normal mixture density assumption for the probability density function of the feature space, the combined supervised-unsupervised learning is always superior to the supervised learning in achieving better estimates. Experimental results are provided to verify the theoretical concepts.

  12. Chapter A2. Selection of Equipment for Water Sampling

    USGS Publications Warehouse

    Wilde, Franceska D.; Radtke, Dean B.; Gibs, Jacob; Iwatsubo, Rick T.

    1998-01-01

    The National Field Manual for the Collection of Water-Quality Data (National Field Manual) describes protocols and provides guidelines for U.S. Geological Survey (USGS) personnel who collect data used to assess the quality of the Nation's surface-water and ground-water resources. This chapter of the manual addresses the selection of equipment commonly used by USGS personnel to collect and process water-quality samples. Each chapter of the National Field Manual is published separately and revised periodically. Newly published and revised chapters will be posted on the World Wide Web on the USGS page 'National Field Manual for the Collection of Water-Quality Data.' The URL for this page is http://pubs.water.usgs.gov/twri9A/ (accessed March 20, 2003).

  13. Multiplex short tandem repeat amplification of low template DNA samples with the addition of proofreading enzymes.

    PubMed

    Davis, Carey P; Chelland, Lynzee A; Pavlova, Victoria R; Illescas, María J; Brown, Kelly L; Cruz, Tracey Dawson

    2011-05-01

    With <100 pg of template DNA, routine short tandem repeat (STR) analysis often fails, resulting in no or partial profiles and increased stochastic effects. To overcome this, some have investigated preamplification methods that include the addition of proofreading enzymes to the PCR cocktail. This project sought to determine whether adding proofreading polymerases directly in the STR amplification mixture would improve the reaction when little template DNA is available. Platinum Taq High Fidelity and GeneAmp High Fidelity were tested in Profiler Plus™ STR reactions alone and in combination with AmpliTaq(®) Gold. All reactions included the additional step of a post-PCR purification step. With both pristine low template DNA and casework samples, the addition of these polymerases resulted in comparable or no improvement in the STR amplification signal. Further, stochastic effects and artifacts were observed equally across all enzyme conditions. Based on these studies, the addition of these proofreading enzymes to a multiplex STR amplification is not recommended for low template DNA work.

  14. Falcon: Visual analysis of large, irregularly sampled, and multivariate time series data in additive manufacturing

    DOE PAGES

    Steed, Chad A.; Halsey, William; Dehoff, Ryan; ...

    2017-02-16

    Flexible visual analysis of long, high-resolution, and irregularly sampled time series data from multiple sensor streams is a challenge in several domains. In the field of additive manufacturing, this capability is critical for realizing the full potential of large-scale 3D printers. Here, we propose a visual analytics approach that helps additive manufacturing researchers acquire a deep understanding of patterns in log and imagery data collected by 3D printers. Our specific goals include discovering patterns related to defects and system performance issues, optimizing build configurations to avoid defects, and increasing production efficiency. We introduce Falcon, a new visual analytics system thatmore » allows users to interactively explore large, time-oriented data sets from multiple linked perspectives. Falcon provides overviews, detailed views, and unique segmented time series visualizations, all with adjustable scale options. To illustrate the effectiveness of Falcon at providing thorough and efficient knowledge discovery, we present a practical case study involving experts in additive manufacturing and data from a large-scale 3D printer. The techniques described are applicable to the analysis of any quantitative time series, though the focus of this paper is on additive manufacturing.« less

  15. Adsorption of Water on JSC-1A Lunar Simulant Samples

    NASA Technical Reports Server (NTRS)

    Goering, John; Sah, Shweta; Burghaus, Uwe; Street, Kenneth W.

    2008-01-01

    Remote sensing probes sent to the moon in the 1990s indicated that water may exist in areas such as the bottoms of deep, permanently shadowed craters at the lunar poles, buried under regolith. Water is of paramount importance for any lunar exploration and colonization project which would require self-sustainable systems. Therefore, investigating the interaction of water with lunar regolith is pertinent to future exploration. The lunar environment can be approximated in ultra-high vacuum systems such as those used in thermal desorption spectroscopy (TDS). Questions about water dissociation, surface wetting, degree of crystallization, details of water-ice transitions, and cluster formation kinetics can be addressed by TDS. Lunar regolith specimens collected during the Apollo missions are still available though precious, so testing with simulant is required before applying to use lunar regolith samples. Hence, we used for these studies JSC-1a, mostly an aluminosilicate glass and basaltic material containing substantial amounts of plagioclase, some olivine and traces of other minerals. Objectives of this project include: 1) Manufacturing samples using as little raw material as possible, allowing the use of surface chemistry and kinetics tools to determine the feasibility of parallel studies on regolith, and 2) Characterizing the adsorption kinetics of water on the regolith simulant. This has implications for the probability of finding water on the moon and, if present, for recovery techniques. For condensed water films, complex TDS data were obtained containing multiple features, which are related to subtle rearrangements of the water adlayer. Results from JSC-1a TDS studies indicate: 1) Water dissociation on JSC-1a at low exposures, with features detected at temperatures as high as 450 K and 2) The formation of 3D water clusters and a rather porous condensed water film. It appears plausible that the sub- m sized particles act as nucleation centers.

  16. RAPID ANALYSIS OF EMERGENCY URINE AND WATER SAMPLES

    SciTech Connect

    Maxwell, S

    2007-02-26

    There is a need for fast, reliable methods for the determination of actinides and Sr-89/90 analysis on environmental and bioassay samples in response to an emergency radiological incident. The SRS (Savannah River Site) Environmental Bioassay Laboratory participated in the National Institute of Standards and Technology Radiochemistry Intercomparison Program (NRIP-06) and analyzed water and urine samples within 8 hours of receipt. The SRS Environmental Laboratory was the only lab that participated in the program that analyzed these samples for both actinides and Sr-89/90 within the requested 8 hour turnaround time. A new, rapid actinide and strontium 89/90 separation method was used for both urine and water samples. This method uses stacked TEVA Resin{reg_sign}, TRU Resin{reg_sign} and Sr-Resin{reg_sign} cartridges from Eichrom Technologies (Darien, IL, USA) that allows the rapid separation of plutonium (Pu), neptunium (Np), uranium (U), and americium (Am), curium (Cm) and thorium (Th) using a single multi-stage column combined with alpha spectrometry. By using vacuum box cartridge technology and stacked cartridges with rapid flow rates, sample preparation time was minimized. This paper discusses the technology and conditions employed for both water and urine samples and presents the SRS performance data on the NRIP-06 samples.

  17. Mutagenicity of water samples from five cities in Korea.

    PubMed

    Park, J H; Kang, K S; Lee, Y S

    2001-07-01

    Four doses (equivalent to 4, 2, 1, and 0.5 liter water) of organic extracts from raw, treated and drinking waters sampled from seven different treatment plants in five cities in Korea were challenged to the Ames test using S. typhimurium strains TA98 and TA100 in the presence/absence of S9 mix. The mutagenicity was usually observed from chlorine-treated (28.6%) and drinking (42.9%) waters rather than raw (3.4%) waters. The strain TA98 (33.3%) was more sensitive to detect the mutagenicity of water samples than the strain TA100 (16.7%). However, the absence of S9 mix showed higher mutagenic activity of waters compared to the presence of S9 mix, corresponding to the detection of 42.9% and 7.1%, respectively. These results indicate that the bacterial mutagenicity of treated and drinking waters may be derived from chlorination in water treatment plants but that the mutagenicity in humans may be limited due to enzymatic metabolism.

  18. Additional studies for the spectrophotometric measurement of iodine in water

    NASA Technical Reports Server (NTRS)

    1972-01-01

    Previous work in iodine spectroscopy is briefly reviewed. Continued studies of the direct spectrophotometric determination of aqueous iodine complexed with potassium iodide show that free iodine is optimally determined at the isosbestic point for these solutions. The effects on iodine determinations of turbidity and chemical substances (in trace amounts) is discussed and illustrated. At the levels tested, iodine measurements are not significantly altered by such substances. A preliminary design for an on-line, automated iodine monitor with eventual capability of operating also as a controller was analyzed and developed in detail with respect single beam colorimeter operating at two wavelengths (using a rotating filter wheel). A flow-through sample cell allows the instrument to operate continuously, except for momentary stop flow when measurements are made. The timed automatic cycling of the system may be interrupted whenever desired, for manual operation. An analog output signal permits controlling an iodine generator.

  19. Effects of Additives, Photodegradation, and Water-tree Degradation on the Photoluminescence in Polyethylene and Polypropylene

    NASA Astrophysics Data System (ADS)

    Ito, Toshihide; Fuse, Norikazu; Ohki, Yoshimichi

    Photoluminescence (PL) spectra induced by irradiation of ultraviolet photons are compared among low-density polyethylene (LDPE), crosslinked polyethylene (XLPE), and polypropylene (PP). Three PL bands appear around 4.2, 3.6, and 3.1 eV in LDPE and XLPE, while similar three PL bands are observed at similar energies in PP. The PL spectra and their decay profiles are independent of the presence of additives and are also independent of whether the samples were crosslinked or not. These results indicate that neither the additives nor the crosslinking has any significant effects on the respective three PLs in PE and PP. When the sample was pre-irradiated by the ultraviolet photons under different atmospheres (air, O2, and vacuum), all the PL intensities decrease with the progress of the pre-irradiation regardless of whether the sample is PE or PP. Therefore, all the PLs are considered to result from impurities. In all the pre-irradiated samples, a new PL band appears at 2.9 eV, of which intensity is stronger when the oxygen partial pressure during the pre-irradiation was lower. This PL is considered to be due to photo-induced conjugated double bonds. It has also been confirmed that water-tree degradation in LDPE or in XLPE does not contribute to PL.

  20. The acid-base impact of free water removal from, and addition to, plasma.

    PubMed

    Haskins, Steve C; Hopper, Kate; Rezende, Marlis L

    2006-03-01

    Water, compared with plasma at a pH of 7.4, is a weak acid. The addition of free water to a patient should have an acidifying effect (dilutional acidosis) and the removal of it, an alkalinizing effect (concentrational alkalosis). The specific effects of free water loss or gain in a relatively complex fluid such as plasma has, to the authors' knowledge, not been reported. This information would be useful in the interpretation of the effect of changes in free water in patients. Plasma samples from goats were either evaporated in a tonometer to 80% of baseline volume or hydrated by the addition of distilled water to 120% of baseline volume. The pH and partial pressure of carbon dioxide, sodium, potassium, ionized calcium, chloride, lactate, phosphorous, albumin, and total protein concentrations were measured. Actual base excess (ABE), standard bicarbonate, anion gap, strong ion difference, strong ion gap, unmeasured anions, and the effects of sodium, chloride, phosphate, and albumin changes on ABE were calculated. Most parameters changed 20% in proportion to the magnitude of dehydration or hydration. Bicarbonate concentration, however, increased only 11% in the evaporation trial and decreased only -2% in the dehydration trial. The evaporation trial was associated with a mild, but significant, metabolic alkalotic effect (ABE increased 3.2 mM/L), whereas the hydration trial was associated with a slight, insignificant metabolic acidotic effect (ABE decreased only 0.6 mM/L). The calculated free water ABE effect (change in sodium concentration) was offset by opposite changes in calculated chloride, lactate, phosphate, and albumin ABE effects.

  1. Holding effects on coliform enumeration in drinking water samples.

    PubMed

    McDaniels, A E; Bordner, R H; Gartside, P S; Haines, J R; Brenner, K P; Rankin, C C

    1985-10-01

    Standard procedures for analyzing drinking water stress the need to adhere to the time and temperature conditions recommended for holding samples collected for microbiological testing. The National Drinking Water Laboratory Certification Program requires compliance with these holding limits, but some investigators have reported difficulties in meeting them. Research was conducted by standard analytical methods to determine if changes occurred when samples were held at 5 and 22 degrees C and analyzed at 0, 24, 30, and 48 h. Samples were analyzed for coliforms by the membrane filter and fermentation-tube procedures and for heterotrophs by the pour plate method. A total of 17 treated water samples were collected from a large municipal distribution system from August to December 1981, and 12 samples were collected from January to May 1983. The samples were dosed with coliforms previously isolated from the water system, Enterobacter cloacae in 1981 and Citrobacter freundii in 1983. The coliform counts declined linearly over time, and the rates of decline were significant at both 5 and 22 degrees C. Within 24 h at 22 degrees C, levels of E. cloacae and C. freundii decreased by 47 and 26%, respectively, and at 5 degrees C, E. cloacae numbers declined by 23%. Results from these representative laboratory-grown coliforms reinforced those previously obtained with naturally occurring coliforms under the same experimental conditions. Significantly, some samples with initially unacceptable counts (greater than 4/100 ml) met the safe drinking water limits after storage at 24 h at 5 and 22 degrees C and would have been classified as satisfactory.(ABSTRACT TRUNCATED AT 250 WORDS)

  2. Sampling and quantifying invertebrates from drinking water distribution mains.

    PubMed

    van Lieverloo, J Hein M; Bosboom, Dick W; Bakker, Geo L; Brouwer, Anke J; Voogt, Remko; De Roos, Josje E M

    2004-03-01

    Water utilities in the Netherlands aim at controlling the multiplication of (micro-) organisms by distributing biologically stable water through biologically stable materials. Disinfectant residuals are absent or very low. To be able to assess invertebrate abundance, methods for sampling and quantifying these animals from distribution mains were optimised and evaluated. The presented method for collecting invertebrates consists of unidirectionally flushing a mains section with a flow rate of 1 ms(-1) and filtering the flushed water in two separate flows with 500 microm and 100 microm mesh plankton gauze filters. Removal efficiency from mains was evaluated in nine experiments by collecting the invertebrates removed from the mains section by intensive cleaning immediately subsequent to sampling. Of 12 taxa distinguished, all except case-building Chironomidae larvae (2%) and Oligochaeta (30%) were removed well (51-75%). Retention of invertebrates in 100 microm filters was evaluated by filtering 39 filtrates using 30 microm filters. Except for flexible and small invertebrates such as Turbellaria (13%), Nematoda (11%) and Copepoda larvae (24%), most taxa were well retained in the 100 microm filters (53-100%). During sample processing, the method for taking sub-samples with a 10 ml pipette from the suspension of samples with high sediment concentrations was found to perform well in 75% of the samples. During a 2-year national survey in the Netherlands and consecutive investigations, the method appeared to be very suitable to assess the abundance of most invertebrate taxa in drinking water distribution systems and to be practicable for relatively inexperienced sampling and lab technicians. Although the numbers of small, less abundant or sessile taxa were not accurately assessed using the method, these taxa probably should not be the primary focus of monitoring by water utilities, as consumer complaints are not likely to be caused by these invertebrates. The accuracy of

  3. Statistical inference for the additive hazards model under outcome-dependent sampling.

    PubMed

    Yu, Jichang; Liu, Yanyan; Sandler, Dale P; Zhou, Haibo

    2015-09-01

    Cost-effective study design and proper inference procedures for data from such designs are always of particular interests to study investigators. In this article, we propose a biased sampling scheme, an outcome-dependent sampling (ODS) design for survival data with right censoring under the additive hazards model. We develop a weighted pseudo-score estimator for the regression parameters for the proposed design and derive the asymptotic properties of the proposed estimator. We also provide some suggestions for using the proposed method by evaluating the relative efficiency of the proposed method against simple random sampling design and derive the optimal allocation of the subsamples for the proposed design. Simulation studies show that the proposed ODS design is more powerful than other existing designs and the proposed estimator is more efficient than other estimators. We apply our method to analyze a cancer study conducted at NIEHS, the Cancer Incidence and Mortality of Uranium Miners Study, to study the risk of radon exposure to cancer.

  4. Statistical inference for the additive hazards model under outcome-dependent sampling

    PubMed Central

    Yu, Jichang; Liu, Yanyan; Sandler, Dale P.; Zhou, Haibo

    2015-01-01

    Cost-effective study design and proper inference procedures for data from such designs are always of particular interests to study investigators. In this article, we propose a biased sampling scheme, an outcome-dependent sampling (ODS) design for survival data with right censoring under the additive hazards model. We develop a weighted pseudo-score estimator for the regression parameters for the proposed design and derive the asymptotic properties of the proposed estimator. We also provide some suggestions for using the proposed method by evaluating the relative efficiency of the proposed method against simple random sampling design and derive the optimal allocation of the subsamples for the proposed design. Simulation studies show that the proposed ODS design is more powerful than other existing designs and the proposed estimator is more efficient than other estimators. We apply our method to analyze a cancer study conducted at NIEHS, the Cancer Incidence and Mortality of Uranium Miners Study, to study the risk of radon exposure to cancer. PMID:26379363

  5. Profile sampling to characterize particulate lead risks in potable water.

    PubMed

    Clark, Brandi; Masters, Sheldon; Edwards, Marc

    2014-06-17

    Traditional lead (Pb) profiling, or collecting sequential liters of water that flow from a consumer tap after a stagnation event, has recently received widespread use in understanding sources of Pb in drinking water and risks to consumer health, but has limitations in quantifying particulate Pb risks. A new profiling protocol was developed in which a series of traditional profiles are collected from the same tap at escalating flow rates. The results revealed marked differences in risks of Pb exposure from one consumer home to another as a function of flow rate, with homes grouped into four risk categories with differing flushing requirements and public education to protect consumers. On average, Pb concentrations detected in water at high flow without stagnation were at least three to four times higher than in first draw samples collected at low flow with stagnation, demonstrating a new "worst case" lead release scenario, contrary to the original regulatory assumption that stagnant, first draw samples contain the highest lead concentrations. Testing also revealed that in some cases water samples with visible particulates had much higher Pb than samples without visible particulates, and tests of different sample handling protocols confirmed that some EPA-allowed methods would not quantify as much as 99.9% of the Pb actually present (avg. 27% of Pb not quantified).

  6. Isotope evidence of hexavalent chromium stability in ground water samples.

    PubMed

    Čadková, Eva; Chrastný, Vladislav

    2015-11-01

    Chromium stable isotopes are of interest in many geochemical studies as a tool to identify Cr(VI) reduction and/or dilution in groundwater aquifers. For such studies the short term stability of Cr(VI) in water samples is required before the laboratory analyses can be carried out. Here the short term stability of Cr(VI) in groundwater samples was studied using an isotope approach. Based on commonly available methods for Cr(VI) stabilization, water samples were filtered and the pH value was adjusted to be equal to or greater than 8 before Cr isotope analysis. Based on our Cr isotope data (expressed as δ(53)CrNIST979), Cr(VI) was found to be unstable over short time periods in anthropogenically contaminated groundwater samples regardless of water treatment (e.g., pH adjustment, different storage temperatures). Based on our laboratory experiments, δ(53)CrNIST979 of the Cr(VI) pool was found to be unstable in the presence of dissolved Fe(II), Mn(IV) and/or SO2. Threshold concentrations of Fe(II) causing Cr(VI) reduction range between 10 mg L(-1) and 100 mg L(-1)and less than 1 mg L(-1) for Mn. Hence our isotope data show that water samples containing Cr(VI) should be processed on-site through anion column chemistry to avoid any isotope shifts.

  7. Gas-driven pump for ground-water samples

    USGS Publications Warehouse

    Signor, Donald C.

    1978-01-01

    Observation wells installed for artificial-recharge research and other wells used in different ground-water programs are frequently cased with small-diameter steel pipe. To obtain samples from these small-diameter wells in order to monitor water quality, and to calibrate solute-transport models, a small-diameter pump with unique operating characteristics is required that causes a minimum alternation of samples during field sampling. A small-diameter gas-driven pump was designed and built to obtain water samples from wells of two-inch diameter or larger. The pump is a double-piston type with the following characteristics: (1) The water sample is isolated from the operating gas, (2) no source of electricity is ncessary, (3) operation is continuous, (4) use of compressed gas is efficient, and (5) operation is reliable over extended periods of time. Principles of operation, actual operation techniques, gas-use analyses and operating experience are described. Complete working drawings and a component list are included. Recent modifications and pump construction for high-pressure applications also are described. (Woodard-USGS)

  8. Effect of Periodic Water Addition on Citric Acid Production in Solid State Fermentation

    NASA Astrophysics Data System (ADS)

    Utpat, Shraddha S.; Kinnige, Pallavi T.; Dhamole, Pradip B.

    2013-09-01

    Water addition is one of the methods used to control the moisture loss in solid state fermentation (SSF). However, none of the studies report the timing of water addition and amount of water to be added in SSF. Therefore, this work was undertaken with an objective to evaluate the performance of periodic water addition on citric acid production in SSF. Experiments were conducted at different moistures (50-80 %) and temperatures (30-40 °C) to simulate the conditions in a fermenter. Citric acid production by Aspergillus niger (ATCC 9029) using sugarcane baggase was chosen as a model system. Based on the moisture profile, citric acid and sugar data, a strategy was designed for periodic addition of water. Water addition at 48, 96, 144 and 192 h enhanced the citric acid production by 62 % whereas water addition at 72, 120, and 168 h increased the citric acid production by just 17 %.

  9. UMTRA project water sampling and analysis plan, Durango, Colorado

    SciTech Connect

    Not Available

    1994-01-01

    Surface remedial action has been completed at the Uranium Mill Tailings Remedial Action Project in Durango, Colorado. Contaminated soil and debris have been removed from the former processing site and placed in the Bodo Canyon disposal cell. Ground water at the former uranium mill/tailings site and raffinate pond area has been contaminated by the former milling operations. The ground water at the disposal site was not impacted by the former milling operations at the time of the cell`s construction. Activities for fiscal 1994 involve ground water sampling and site characterization of the disposal site.

  10. 75 FR 41725 - Food Additives Permitted in Feed and Drinking Water of Animals; Ammonium Formate

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-19

    ... Additives Permitted in Feed and Drinking Water of Animals; Ammonium Formate AGENCY: Food and Drug... regulations for food additives permitted in feed and drinking water of animals to provide for the safe use of... DRINKING WATER OF ANIMALS 0 1. The authority citation for 21 CFR part 573 continues to read as...

  11. Stability of low levels of perchlorate in drinking water and natural water samples

    USGS Publications Warehouse

    Stetson, S.J.; Wanty, R.B.; Helsel, D.R.; Kalkhoff, S.J.; Macalady, D.L.

    2006-01-01

    Perchlorate ion (ClO4-) is an environmental contaminant of growing concern due to its potential human health effects, impact on aquatic and land animals, and widespread occurrence throughout the United States. The determination of perchlorate cannot normally be carried out in the field. As such, water samples for perchlorate analysis are often shipped to a central laboratory, where they may be stored for a significant period before analysis. The stability of perchlorate ion in various types of commonly encountered water samples has not been generally examined-the effect of such storage is thus not known. In the present study, the long-term stability of perchlorate ion in deionized water, tap water, ground water, and surface water was examined. Sample sets containing approximately 1000, 100, 1.0, and 0.5 ??g l-1 perchlorate ion in deionized water and also in local tap water were formulated. These samples were analyzed by ion chromatography for perchlorate ion concentration against freshly prepared standards every 24 h for the first 7 days, biweekly for the next 4 weeks, and periodically after that for a total of 400 or 610 days for the two lowest concentrations and a total of 428 or 638 days for the high concentrations. Ground and surface water samples containing perchlorate were collected, held and analyzed for perchlorate concentration periodically over at least 360 days. All samples except for the surface water samples were found to be stable for the duration of the study, allowing for holding times of at least 300 days for ground water samples and at least 90 days for surface water samples. ?? 2006 Elsevier B.V. All rights reserved.

  12. An evaluation of drinking water samples treated with alternative disinfectants

    SciTech Connect

    Patterson, K.S.; Lykins, B.W. Jr.; Garner, L.M.

    1995-10-01

    Due to concern over potential human health risks associated with the use of chlorine (Cl{sub 2}) for disinfection of drinking water, many utilities are considering alternative disinfectants. An evaluation is thus needed of the potential risks associated with the use of alternative disinfectants relative to those posed by Cl{sub 2}. At a pilot-scale drinking water plant in Jefferson Parish, LA., two studies were conducted in which clarified and sand filtered Mississippi River water was treated with either ozone (O{sub 3}), monochloramine (NH{sub 2}Cl), Cl{sub 2} or was not disinfected. Ozonated water was also post-disinfected with either NH{sub 2}Cl or Cl{sub 2}, to provide a disinfectant residual. For each treatment stream total organic carbon (TOC), total organic halide (TOX) and microbiological contaminants were determined. XAD resin concentrates were also prepared for mutagenicity testing in the Ames Salmonella assay. Water samples disinfected with O{sub 3} alone had low levels of mutagenic activity, the same as the non-disinfected water. The level of mutagenicity observed following chlorination was approximately twice that observed following treatment with NH{sub 2}Cl. Disinfection with O{sub 3} prior to treatment with either Cl{sub 2} or NH{sub 2}Cl resulted in a significantly lower level of mutagenicity than when either disinfectant was used alone. The concentrations of TOX present in the water samples showed a pattern similar to that of the mutagenicity data. The levels of TOC, by contrast, were similar for all the treatment streams. No significant baterial contamination was observed in water samples treated with either Cl{sub 2} or NH{sub 2}Cl alone or in combination with O{sub 3}, as determined by heterotrophic plate counts. However, O{sub 3} alone did not insure an acceptable level of disinfection at the end of the treatment stream.

  13. Analysis of water in Autonomous Biological Systems (ABS) samples.

    PubMed

    Ishikawa, Y; Kobayashi, K; Seki, K; Mizutani, H; Kawasaki, Y; Koike, J; Ijiri, K; Yamashita, M; Sugiura, K; Poynter, J; MacCallum, T; Anderson, G

    1998-12-01

    Several soluble components, peptidase and amino acids, and carbon isotopic ratio in the water retrieved from flight experiments of Autonomous Biological Systems (ABS) as well as ground control samples are analyzed to interpret the condition, dynamics, material balance of the ABS ecosystems. Organic carbons in flight samples were found to be more abundant compared with the control ones, which suggested the uniform ecosystems in low gravity might easily dissolve more soluble components. The Mir-1997 flight sample showed higher C/N ratio probably because of the dissolution of carbon-rich plant materials.

  14. Downhole pumps for water sampling in small diameter wells

    USGS Publications Warehouse

    Koopman, F. C.

    1979-01-01

    The relatively high cost and difficulty in locating a source of pumps for use in obtaining ground-water samples from small-diameter wells has demonstrated a need for this report. Criteria for selection of a pump and pumping equipment to meet specific requirements has been tabulated to assist field personnel in making a selection from commercial sources. (Kosco-USGS)

  15. THE EMPACT BEACHES: A CASE STUDY IN RECREATIONAL WATER SAMPLING

    EPA Science Inventory

    Various chapters describe sample and experimental design, use of a geometric mean or an arithmetic mean, modeling and forecasting, and risk assessment in relation to monitoring recreational waters for fecal indicators. All of these aspects of monitoring are dependent on the spat...

  16. Filtration recovery of extracellular DNA from environmental water samples

    EPA Science Inventory

    qPCR methods are able to analyze DNA from microbes within hours of collecting water samples, providing the promptest notification and public awareness possible when unsafe pathogenic levels are reached. Health risk, however, may be overestimated by the presence of extracellular ...

  17. A water soluble additive to suppress respirable dust from concrete-cutting chainsaws: a case study.

    PubMed

    Summers, Michael P; Parmigiani, John P

    2015-01-01

    Respirable dust is of particular concern in the construction industry because it contains crystalline silica. Respirable forms of silica are a severe health threat because they heighten the risk of numerous respirable diseases. Concrete cutting, a common work practice in the construction industry, is a major contributor to dust generation. No studies have been found that focus on the dust suppression of concrete-cutting chainsaws, presumably because, during normal operation water is supplied continuously and copiously to the dust generation points. However, there is a desire to better understand dust creation at low water flow rates. In this case study, a water-soluble surfactant additive was used in the chainsaw's water supply. Cutting was performed on a free-standing concrete wall in a covered outdoor lab with a hand-held, gas-powered, concrete-cutting chainsaw. Air was sampled at the operator's lapel, and around the concrete wall to simulate nearby personnel. Two additive concentrations were tested (2.0% and 0.2%), across a range of fluid flow rates (0.38-3.8 Lpm [0.1-1.0 gpm] at 0.38 Lpm [0.1 gpm] increments). Results indicate that when a lower concentration of additive is used exposure levels increase. However, all exposure levels, once adjusted for 3 hours of continuous cutting in an 8-hour work shift, are below the Occupational Safety and Health Administration (OSHA) permissible exposure limit (PEL) of 5 mg/m(3). Estimates were made using trend lines to predict the fluid flow rates that would cause respirable dust exposure to exceed both the OSHA PEL and the American Conference of Governmental Industrial Hygienists (ACGIH®) threshold limit value (TLV).

  18. Guidelines and techniques for obtaining water samples that accurately represent the water chemistry of an aquifer

    USGS Publications Warehouse

    Claassen, Hans C.

    1982-01-01

    Obtaining ground-water samples that accurately represent the water chemistry of an aquifer is a complex task. Before a ground-water sampling program can be started, an understanding of the kind of chemical data needed and the potential changes in water chemistry resulting from various drilling, well-completion, and sampling techniques is needed. This report provides a basis for such an evaluation and permits a choice of techniques that will result in obtaining the best possible data for the time and money allocated.

  19. Determination of estrogenic potential in waste water without sample extraction.

    PubMed

    Avberšek, Miha; Žegura, Bojana; Filipič, Metka; Uranjek-Ževart, Nataša; Heath, Ester

    2013-09-15

    This study describes the modification of the ER-Calux assay for testing water samples without sample extraction (NE-(ER-Calux) assay). The results are compared to those obtained with ER-Calux assay and a theoretical estrogenic potential obtained by GC-MSD. For spiked tap and waste water samples there was no statistical difference between estrogenic potentials obtained by the three methods. Application of NE-(ER-Calux) to "real" influent and effluents from municipal waste water treatment plants and receiving surface waters found that the NE-(ER-Calux) assay gave higher values compared to ER-Calux assay and GC-MSD. This is explained by the presence of water soluble endocrine agonists that are usually removed during extraction. Intraday dynamics of the estrogenic potential of a WWTP influent and effluent revealed an increase in the estrogenic potential of the influent from 12.9 ng(EEQ)/L in the morning to a peak value of 40.0 ng(EEQ)/L in the afternoon. The estrogenic potential of the effluent was

  20. Total Water Content Measurements with an Isokinetic Sampling Probe

    NASA Technical Reports Server (NTRS)

    Reehorst, Andrew L.; Miller, Dean R.; Bidwell, Colin S.

    2010-01-01

    The NASA Glenn Research Center has developed a Total Water Content (TWC) Isokinetic Sampling Probe. Since it is not sensitive to cloud water particle phase nor size, it is particularly attractive to support super-cooled large droplet and high ice water content aircraft icing studies. The instrument is comprised of the Sampling Probe, Sample Flow Control, and Water Vapor Measurement subsystems. Analysis and testing have been conducted on the subsystems to ensure their proper function and accuracy. End-to-end bench testing has also been conducted to ensure the reliability of the entire instrument system. A Stokes Number based collection efficiency correction was developed to correct for probe thickness effects. The authors further discuss the need to ensure that no condensation occurs within the instrument plumbing. Instrument measurements compared to facility calibrations from testing in the NASA Glenn Icing Research Tunnel are presented and discussed. There appears to be liquid water content and droplet size effects in the differences between the two measurement techniques.

  1. Sampling vadose-zone water for a volatile organic compound at Picatinny Arsenal, New Jersey

    USGS Publications Warehouse

    Smith, James A.; Cho, H. Jean; Jaffe, Peter R.; MacLeod, Cecilia L.; Koehnlein, Susan A.

    1992-01-01

    A new method of collecting samples of unsaturated-zone water for quantitative analysis for a volatile organic compound, trichloroethene (TCE), was compared to three other, previously described sampling methodologies in the laboratory and in the field. In the laboratory, prepared water samples containing TCE in a known concentration (20 µg/L) were sampled repeatedly by using each of the four methods to quantify method precision and accuracy. To compare the four methods in the field, unsaturated-zone water above a TCE-contaminated water-table aquifer was transferred from a depth of 2 m to land surface with 0.15-m-long suction lysimeters attached to 1.85-m lengths of stainless-steel tubing. Statistical analyses of the laboratory and field data indicate that the new method, which involves collecting the water samples in gas-tight glass syringes, is superior to the other three methods for the quantitative sampling and analysis of TCE on the basis of its high precision and accuracy and ease of use. This method was used to collect additional samples from the field site to quantify the spatial variability of TCE concentrations in the unsaturated-zone water. Results of analysis of variance of the data indicate that the spatial concentration variability is important, and that differences in TCE concentration are statistically significant for horizontal distances less than 3.6 m.

  2. Investigations of Sample Stability in Water Chemistry Samples: Implications for the National Aquatic Resource Surveys

    EPA Science Inventory

    Water samples collected for the EPA's National Aquatic Resource Surveys (NARS) typically arrive at an analytical laboratory 2 or 3 days after collection (longer if collected from a remote location), at which point they are stabilized (filtration and/or acid preservation) until an...

  3. Standard reference water samples for rare earth element determinations

    USGS Publications Warehouse

    Verplanck, P.L.; Antweiler, R.C.; Nordstrom, D.K.; Taylor, H.E.

    2001-01-01

    Standard reference water samples (SRWS) were collected from two mine sites, one near Ophir, CO, USA and the other near Redding, CA, USA. The samples were filtered, preserved, and analyzed for rare earth element (REE) concentrations (La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu) by inductively coupled plasma-mass spectrometry (ICP-MS). These two samples were acid mine waters with elevated concentrations of REEs (0.45-161 ??g/1). Seventeen international laboratories participated in a 'round-robin' chemical analysis program, which made it possible to evaluate the data by robust statistical procedures that are insensitive to outliers. The resulting most probable values are reported. Ten to 15 of the participants also reported values for Ba, Y, and Sc. Field parameters, major ion, and other trace element concentrations, not subject to statistical evaluation, are provided.

  4. Use of additives to enhance the removal of phenols from water treated with horseradish and hydrogen peroxide.

    PubMed

    Tonegawa, Masami; Dec, Jerzy; Bollag, Jean-Marc

    2003-01-01

    Use of additives, such as polyethylene glycol (PEG), selected surfactants, chitosan gel, or activated carbon, has been shown to enhance enzymatic treatment of water polluted with organic compounds. In this study, additives were used to facilitate the removal of 2,4-dichlorophenol (2,4-DCP) from water using minced horseradish (Armoracia rusticana P. Gaertn. et al.) as a carrier of peroxidase activity. The specific objectives of the study were to (i) enhance the pollutant removal activity of minced horseradish by the addition of PEG and other additives (e.g., Tween 20, Triton X-100, and rhamnolipid); (ii) eliminate colored reaction products by the addition of chitosan; and (iii) eliminate color by amending treated water with activated carbon. The disappearance of 2,4-DCP in horseradish-treated water samples amended with PEG or various surfactants (75-90%) was greatly increased over that observed in nonamended samples (29%). The effect of PEG depended on its average molecular weight. As indicated by visible spectrophotometry, enclosing horseradish pieces between two sealed chitosan films completely eliminated colored reaction products; however, the decolorization was accompanied by a reduction in 2,4-DCP removal (from 95 to 60%). On the other hand, commercially available activated carbon completely removed colored reaction products from the treated water without reducing the removal efficiency. Based on the results obtained, it can be concluded that the use of additives may considerably improve the quality of wastewater treated by plant materials.

  5. Evaluation of Additives to Eliminate Free Water from Aviation Fuel Light Obscuration Particle Counts

    DTIC Science & Technology

    2015-11-01

    5000 DISTRIBUTION A. Approved for public release: distribution unlimited. Evaluation of Additives to Eliminate Free Water from Aviation Fuel Light...April 2015 4. TITLE AND SUBTITLE Evaluation of Additives to Eliminate Free Water from Aviation Fuel Light Obscuration Particle Counts 5a. CONTRACT...13. SUPPLEMENTARY NOTES 14. ABSTRACT This technical report details the evaluation fuel additives used to eliminate the effects of free water

  6. Spectral analysis of water samples using modulated resonance features for monitoring of public water resources

    NASA Astrophysics Data System (ADS)

    Lambrakos, S. G.; Yapijakis, C.; Aiken, D.; Shabaev, A.; Ramsey, S.; Peak, J.

    2015-05-01

    Hyperspectral analysis of water samples taken from public water resources in the New York City metro area has demonstrated the potential application of this type of analysis for water monitoring, treatment and evaluation prior to filtration. Hyperspectral monitoring of contaminants with respect to types and relative concentrations requires tracking statistical profiles of water contaminants in terms of spatial-temporal distributions of electromagnetic absorption spectra ranging from the ultraviolet to infrared, which are associated with specific water resources. To achieve this, it is necessary to establish correlation between hyperspectral signatures and types of contaminants to be found within specific water resources. Correlation between absorption spectra and changes in chemical and physical characteristics of contaminants requires sufficient sensitivity. The present study examines the sensitivity of modulated resonance features with respect to characteristics of water contaminants for hyperspectral analysis of water samples.

  7. A new method of snowmelt sampling for water stable isotopes

    USGS Publications Warehouse

    Penna, D.; Ahmad, M.; Birks, S. J.; Bouchaou, L.; Brencic, M.; Butt, S.; Holko, L.; Jeelani, G.; Martinez, D. E.; Melikadze, G.; Shanley, J.B.; Sokratov, S. A.; Stadnyk, T.; Sugimoto, A.; Vreca, P.

    2014-01-01

    We modified a passive capillary sampler (PCS) to collect snowmelt water for isotopic analysis. Past applications of PCSs have been to sample soil water, but the novel aspect of this study was the placement of the PCSs at the ground-snowpack interface to collect snowmelt. We deployed arrays of PCSs at 11 sites in ten partner countries on five continents representing a range of climate and snow cover worldwide. The PCS reliably collected snowmelt at all sites and caused negligible evaporative fractionation effects in the samples. PCS is low-cost, easy to install, and collects a representative integrated snowmelt sample throughout the melt season or at the melt event scale. Unlike snow cores, the PCS collects the water that would actually infiltrate the soil; thus, its isotopic composition is appropriate to use for tracing snowmelt water through the hydrologic cycle. The purpose of this Briefing is to show the potential advantages of PCSs and recommend guidelines for constructing and installing them based on our preliminary results from two snowmelt seasons.

  8. Interstitial water studies on small core samples, Leg 9

    USGS Publications Warehouse

    Sayles, F.L.; Waterman, L.S.; Manheim, F. T.

    1972-01-01

    The chemistry of the pore fluids obtained on Leg 9 is remarkable primarily in its constancy. Excepting silicon and strontium, only at one site do the concentrations of the major and minor constituents deviate notably from sea water concentrations (see Tables 1 and 2). The trends, or lack of them, seen in these samples have been discussed previously and only references will be given here. The constancy of composition and similarity to sea water is particularly noteworthy, as the sediments at all of the 9 sites are thought to be intruded by the basal basalt. The pore fluid chemistry exhibits no evidence of intrusion except possibly at Site 84.

  9. Water vapor measurement system in global atmospheric sampling program, appendix

    NASA Technical Reports Server (NTRS)

    Englund, D. R.; Dudzinski, T. J.

    1982-01-01

    The water vapor measurement system used in the NASA Global Atmospheric Sampling Program (GASP) is described. The system used a modified version of a commercially available dew/frostpoint hygrometer with a thermoelectrically cooled mirror sensor. The modifications extended the range of the hygrometer to enable air sample measurements with frostpoint temperatures down to -80 C at altitudes of 6 to 13 km. Other modifications were made to permit automatic, unattended operation in an aircraft environment. This report described the hygrometer, its integration with the GASP system, its calibration, and operational aspects including measurement errors. The estimated uncertainty of the dew/frostpoint measurements was + or - 1.7 Celsius.

  10. Spectrophotometric determination of trace copper in water samples with thiomichlersketone

    NASA Astrophysics Data System (ADS)

    Fu, Dayou; Yuan, Dong

    2007-02-01

    A simple and sensitive spectrophotometric method for determination of trace copper in water samples is proposed. In the presence of pH 4.6 HAc-NaAc buffer solution and surfactant polyethylene octyl phenyl ether (OP) medium, copper reacts with thiomichlersketone (TMK) to form a stable 1:4 complex. The complex Cu(II)-TMK-OP shows maximum absorbance at 500 nm with a molar absorptivity value of 5.7 × 10 4 l mol -1 cm -1. Beer's law is obeyed for copper concentrations in the range of 0-15 μg/25 ml. The average recovery of copper is between 95.8 and 106%. The method has been applied for determination of trace copper in different water samples with satisfactory results.

  11. Surface Water Sampling Data for BP Spill/Deepwater Horizon

    EPA Pesticide Factsheets

    The Deepwater Horizon oil spill (also referred to as the BP oil spill) began on 20 April 2010 in the Gulf of Mexico on the BP-operated Macondo Prospect. Following the explosion and sinking of the Deepwater Horizon oil rig, a sea-floor oil gusher flowed for 87 days, until it was capped on 15 July 2010.In response to the BP oil spill, EPA sampled air, water, sediment, and waste generated by the cleanup operations.

  12. Water Sampling Data for BP Spill/Deepwater Horizon

    EPA Pesticide Factsheets

    The Deepwater Horizon oil spill (also referred to as the BP oil spill) began on 20 April 2010 in the Gulf of Mexico on the BP-operated Macondo Prospect. Following the explosion and sinking of the Deepwater Horizon oil rig, a sea-floor oil gusher flowed for 87 days, until it was capped on 15 July 2010.In response to the BP oil spill, EPA sampled air, water, sediment, and waste generated by the cleanup operations.

  13. RAPID SEPARATION METHOD FOR EMERGENCY WATER AND URINE SAMPLES

    SciTech Connect

    Maxwell, S.; Culligan, B.

    2008-08-27

    The Savannah River Site Environmental Bioassay Lab participated in the 2008 NRIP Emergency Response program administered by the National Institute for Standards and Technology (NIST) in May, 2008. A new rapid column separation method was used for analysis of actinides and {sup 90}Sr the NRIP 2008 emergency water and urine samples. Significant method improvements were applied to reduce analytical times. As a result, much faster analysis times were achieved, less than 3 hours for determination of {sup 90}Sr and 3-4 hours for actinides. This represents a 25%-33% improvement in analysis times from NRIP 2007 and a {approx}100% improvement compared to NRIP 2006 report times. Column flow rates were increased by a factor of two, with no significant adverse impact on the method performance. Larger sample aliquots, shorter count times, faster cerium fluoride microprecipitation and streamlined calcium phosphate precipitation were also employed. Based on initial feedback from NIST, the SRS Environmental Bioassay Lab had the most rapid analysis times for actinides and {sup 90}Sr analyses for NRIP 2008 emergency urine samples. High levels of potential matrix interferences may be present in emergency samples and rugged methods are essential. Extremely high levels of {sup 210}Po were found to have an adverse effect on the uranium results for the NRIP-08 urine samples, while uranium results for NRIP-08 water samples were not affected. This problem, which was not observed for NRIP-06 or NRIP-07 urine samples, was resolved by using an enhanced {sup 210}Po removal step, which will be described.

  14. An opacity-sampled treatment of water vapor

    NASA Technical Reports Server (NTRS)

    Alexander, David R.; Augason, Gordon C.; Johnson, Hollis R.

    1989-01-01

    Although the bands of H2O are strong in the spectra of cool stars and calculations have repeatedly demonstrated their significance as opacity sources, only approximate opacities are currently available, due both to the difficulty of accounting for the millions of lines involved and to the inadequacy of laboratory and theoretical data. To overcome these obstacles, a new treatment is presented, based upon a statistical representation of the water vapor spectrum derived from available laboratory data. This statistical spectrum of water vapor employs an exponential distribution of line strengths and random positions of lines whose overall properties are forced to reproduce the mean opacities observed in the laboratory. The resultant data set is then treated by the opacity-sampling method exactly as are all other lines, both molecular and atomic. Significant differences are found between the results of this improved treatment and the results obtained with previous treatments of water-vapor opacity.

  15. GROUND WATER SAMPLING OF VOCS IN THE WATER/CAPILLARY FRINGE AREA FOR VAPOR INTRUSION ASSESSMENT

    EPA Science Inventory

    Vapor intrusion has recently been considered a major pathway for increased indoor air contamination from certain volatile organic contaminants (VOCs). The recent Draft EPA Subsurface Vapor Intrusion Guidance Document states that ground water samples should be obtained from the u...

  16. Calculating of river water quality sampling frequency by the analytic hierarchy process (AHP).

    PubMed

    Do, Huu Tuan; Lo, Shang-Lien; Phan Thi, Lan Anh

    2013-01-01

    River water quality sampling frequency is an important aspect of the river water quality monitoring network. A suitable sampling frequency for each station as well as for the whole network will provide a measure of the real water quality status for the water quality managers as well as the decision makers. The analytic hierarchy process (AHP) is an effective method for decision analysis and calculation of weighting factors based on multiple criteria to solve complicated problems. This study introduces a new procedure to design river water quality sampling frequency by applying the AHP. We introduce and combine weighting factors of variables with the relative weights of stations to select the sampling frequency for each station, monthly and yearly. The new procedure was applied for Jingmei and Xindian rivers, Taipei, Taiwan. The results showed that sampling frequency should be increased at high weighted stations while decreased at low weighted stations. In addition, a detailed monitoring plan for each station and each month could be scheduled from the output results. Finally, the study showed that the AHP is a suitable method to design a system for sampling frequency as it could combine multiple weights and multiple levels for stations and variables to calculate a final weight for stations, variables, and months.

  17. EPA GROUND WATER ISSUE: Ground Water Sample Preservation at ISCO Sites – Recommended Guidelines

    EPA Science Inventory

    In-situ chemical oxidation (ISCO) involves the introduction of a chemical oxidant into the subsurface for the purpose of transforming ground water contaminants into harmless byproducts. Due to oxidant persistence, ground water samples collected at hazardous waste sites may contai...

  18. Solventless and solvent-minimized sample preparation techniques for determining currently used pesticides in water samples: a review.

    PubMed

    Tankiewicz, Maciej; Fenik, Jolanta; Biziuk, Marek

    2011-10-30

    The intensification of agriculture means that increasing amounts of toxic organic and inorganic compounds are entering the environment. The pesticides generally applied nowadays are regarded as some of the most dangerous contaminants of the environment. Their presence in the environment, especially in water, is hazardous because they cause human beings to become more susceptible to disease. For these reasons, it is essential to monitor pesticide residues in the environment with the aid of all accessible analytical methods. The analysis of samples for the presence of pesticides is problematic, because of the laborious and time-consuming operations involved in preparing samples for analysis, which themselves may be a source of additional contaminations and errors. To date, it has been standard practice to use large quantities of organic solvents in the sample preparation process; but as these solvents are themselves hazardous, solventless and solvent-minimized techniques are coming into use. This paper discusses the most commonly used over the last 15 years sample preparation techniques for monitoring organophosphorus and organonitrogen pesticides residue in water samples. Furthermore, a significant trend in sample preparation, in accordance with the principles of 'Green Chemistry' is the simplification, miniaturization and automation of analytical techniques. In view of this aspect, several novel techniques are being developed in order to reduce the analysis step, increase the sample throughput and to improve the quality and the sensitivity of analytical methods. The paper describes extraction techniques requiring the use of solvents - liquid-liquid extraction (LLE) and its modifications, membrane extraction techniques, hollow fibre-protected two-phase solvent microextraction, liquid phase microextraction based on the solidification of a floating organic drop (LPME-SFO), solid-phase extraction (SPE) and single-drop microextraction (SDME) - as well as solvent

  19. Arsenic-related water quality with depth and water quality of well-head samples from production wells, Oklahoma, 2008

    USGS Publications Warehouse

    Becker, Carol J.; Smith, S. Jerrod; Greer, James R.; Smith, Kevin A.

    2010-01-01

    The U.S. Geological Survey well profiler was used to describe arsenic-related water quality with well depth and identify zones yielding water with high arsenic concentrations in two production wells in central and western Oklahoma that yield water from the Permian-aged Garber-Wellington and Rush Springs aquifers, respectively. In addition, well-head samples were collected from 12 production wells yielding water with historically large concentrations of arsenic (greater than 10 micrograms per liter) from the Garber-Wellington aquifer, Rush Springs aquifer, and two minor aquifers: the Arbuckle-Timbered Hills aquifer in southern Oklahoma and a Permian-aged undefined aquifer in north-central Oklahoma. Three depth-dependent samples from a production well in the Rush Springs aquifer had similar water-quality characteristics to the well-head sample and did not show any substantial changes with depth. However, slightly larger arsenic concentrations in the two deepest depth-dependent samples indicate the zones yielding noncompliant arsenic concentrations are below the shallowest sampled depth. Five depth-dependent samples from a production well in the Garber-Wellington aquifer showed increases in arsenic concentrations with depth. Well-bore travel-time information and water-quality data from depth-dependent and well-head samples showed that most arsenic contaminated water (about 63 percent) was entering the borehole from perforations adjacent to or below the shroud that overlaid the pump. Arsenic concentrations ranged from 10.4 to 124 micrograms per liter in 11 of the 12 production wells sampled at the well head, exceeding the maximum contaminant level of 10 micrograms per liter for drinking water. pH values of the 12 well-head samples ranged from 6.9 to 9. Seven production wells in the Garber-Wellington aquifer had the largest arsenic concentrations ranging from 18.5 to 124 micrograms per liter. Large arsenic concentrations (10.4-18.5) and near neutral to slightly alkaline

  20. Asotin Creek ISCO Water Sample Data Summary: Water Year 2002, Annual Report 2001-2002.

    SciTech Connect

    Peterson, Stacia

    2003-08-01

    The Pomeroy Ranger District operates 3 automated water samplers (ISCOs) in the Asotin Creek drainage in cooperation with the Asotin Model Watershed. The samplers are located on Asotin Creek: Asotin Creek at the mouth, Asotin Creek at Koch site, and South Fork Asotin Creek above the forks. At the end of Water Year (WY) 2001 we decided to sample from Oct. 1 through June 30 of each water year. This decision was based on the difficulty of obtaining good low flow samples, since the shallow depth of water often meant that instrument intakes were on the bed of the river and samples were contaminated with bed sediments. The greatest portion of suspended sediment is transported during the higher flows of fall and especially during the spring snow runoff period, and sampling the shorter season should allow characterization of the sediment load of the river. The ISCO water samplers collected a daily composite sample of 4 samples per day into one bottle at 6-hour intervals until late March when they were reprogrammed to collect 3 samples per day at 8-hour intervals. This was done to reduce battery use since battery failure had become an ongoing problem. The water is picked up on 24-day cycles and brought to the Forest Service Water Lab in Pendleton, OR. The samples are analyzed for total suspended solids (TSS), conductivity, and turbidity. A total dissolved solids value is estimated based on conductivity. The USGS gage, Asotin Creek at the mouth, No.13335050 has been discontinued and there are no discharge records available for this period.

  1. Evidence That Certain Waste Tank Headspace Vapor Samples Were Contaminated by Semivolatile Polymer Additives

    SciTech Connect

    Huckaby, James L.

    2006-02-09

    Vapor samples collected from the headspaces of the Hanford Site high-level radioactive waste tanks in 1994 and 1995 using the Vapor Sampling System (VSS) were reported to contain trace levels of phthalates, antioxidants, and certain other industrial chemicals that did not have a logical origin in the waste. This report examines the evidence these chemicals were sampling artifacts (contamination) and identifies the chemicals reported as headspace constituents that may instead have been contaminants. Specific recommendations are given regarding the marking of certain chemicals as suspect on the basis they were sampling manifold contaminants.

  2. Adsorption of Water on Simulated Moon Dust Samples

    NASA Technical Reports Server (NTRS)

    Goering, John P.; Sah, Shweta; Burghaus, Uwe; Street, Kenneth W., Jr.

    2008-01-01

    A lunar regolith simulant dust sample (JSC-1a) supported on a silica wafer (SiO2/Si(111)) has been characterized by scanning electron microscopy (SEM), energy dispersive x-ray spectroscopy (EDX), and Auger electron spectroscopy (AES). The adsorption kinetics of water has been studied primarily by thermal desorption spectroscopy (TDS) and also by collecting isothermal adsorption transients. The support has been characterized by water TDS. JSC-1a consists mostly of aluminosilicate glass and other minerals containing Fe, Na, Ca, and Mg. The particle sizes span the range from a few microns up to 100 microns. At small exposures, H2O TDS is characterized by broad (100 to 450 K) structures; at large exposures distinct TDS peaks emerge that are assigned to amorphous solid water (145 K) and crystalline ice (165 K). Water dissociates on JSC-1a at small exposures but not on the bare silica support. It appears that rather porous condensed ice layers form at large exposures. At thermal impact energies, the initial adsorption probability amounts to 0.92+/-0.05.

  3. Isolation and identification of Arcobacter species from environmental and drinking water samples.

    PubMed

    Talay, Funda; Molva, Celenk; Atabay, Halil Ibrahim

    2016-11-01

    Water plays an important role in the transmission of Arcobacter spp. to animals and humans. The aim of this study was to isolate and characterize Arcobacter spp. from 115 different water samples (66 sewage, 25 rivers, 16 spring water, and 8 drinking water) in Izmir, Turkey. In total, 41 samples (35.7 %) were found positive for Arcobacter spp. by the genus-specific PCR. Arcobacter butzleri was detected in 39 out of 115 samples (33.9 %) including 24 sewage, 13 rivers, and 2 spring water. The remaining Arcobacter spp. (n = 2) isolates could not be identified by m-PCR and 16S rRNA gene sequencing. Based on the phenotypic characterization, most of the Arcobacter species (87.8 %) indicated weak catalase activity. In addition, there were differences in phenotypic patterns among isolated species during growth at 37 °C under microaerobic and aerobic conditions, in the presence of 2 % (39/41) and 3.5 % (32/41) NaCl and 0.04 % TTC (39/41) and on MacConkey agar (38/41). The results of this study indicated that environmental water samples are common sources for Arcobacter spp. Therefore, effective control measures should be taken to protect human health.

  4. UMTRA Project water sampling and analysis plan, Salt Lake City, Utah. Revision 1

    SciTech Connect

    1995-06-01

    This water sampling and analysis plan describes planned, routine ground water sampling activities at the US Department of Energy Uranium Mill Tailings Remedial Action Project site in Salt Lake City, Utah. This plan identifies and justifies sampling locations, analytical parameters, detection limits, and sampling frequencies for routine monitoring of ground water, sediments, and surface waters at monitoring stations on the site.

  5. Electrochemical determination of pharmaceuticals in spiked water samples.

    PubMed

    Ambrosi, Adriano; Antiochia, Riccarda; Campanella, Luigi; Dragone, Roberto; Lavagnini, Irma

    2005-07-15

    The electrochemical behaviour of acidic and neutral pharmaceutical active compounds (PhACs) was studied by cyclic voltammetry and pulse voltammetric techniques on mercury, carbon nanotube paste, carbon paste and gold electrodes. The best results, in terms of sensitivity, linearity range and detection limits, were obtained by differential pulse voltammetry (DPV) for ofloxacin (LOD 5.2 microM), differential pulse polarography (DPP) for clofibric acid (LOD 4.7 microM) and normal pulse voltammetry (NPV) for diclofenac (LOD 0.8 microM) and propranolol (LOD 0.5 microM). An enrichment step of approximately two orders of magnitude was performed by a solid-phase extraction procedure (SPE) in order to concentrate the samples. The developed method was optimized and tested on spiked river water samples.

  6. Addition of chlorine during water purification reduces iodine content of drinking water and contributes to iodine deficiency.

    PubMed

    Samson, L; Czegeny, I; Mezosi, E; Erdei, A; Bodor, M; Cseke, B; Burman, K D; Nagy, E V

    2012-01-01

    Drinking water is the major natural source of iodine in many European countries. In the present study, we examined possible sites of iodine loss during the usual water purification process.Water samples from 6 sites during the technological process were taken and analyzed for iodine content. Under laboratory circumstances, prepared iodine in water solution has been used as a model to test the effect of the presence of chlorine. Samples from the purification sites revealed that in the presence of chlorine there is a progressive loss of iodine from the water. In the chlorine concentrations employed in the purification process, 24-h chlorine exposure eliminated more than 50% of iodine when the initial iodine concentration was 250 μg/l or less. Iodine was completely eliminated if the starting concentration was 16 μg/l.We conclude that chlorine used during water purification may be a major contributor to iodine deficiency in European communities.

  7. Investigating Arsenic Contents in Surface and Drinking Water by Voltammetry and the Method of Standard Additions

    ERIC Educational Resources Information Center

    Cheng, Anran; Tyne, Rebecca; Kwok, Yu Ting; Rees, Louis; Craig, Lorraine; Lapinee, Chaipat; D'Arcy, Mitch; Weiss, Dominik J.; Salau¨n, Pascal

    2016-01-01

    Testing water samples for arsenic contamination has become an important water quality issue worldwide. Arsenic usually occurs in very small concentrations, and a sensitive analytical method is needed. We present here a 1-day laboratory module developed to introduce Earth Sciences and/or Chemistry student undergraduates to key aspects of this…

  8. Analysis of native water, bed material, and elutriate samples of major Louisiana waterways, 1975

    USGS Publications Warehouse

    Demas, Charles R.

    1976-01-01

    The U.S. Geological Survey, in cooperation with the U.S. Army Corps of Engineers, conducted a series of elutriate studies in selected reaches of major navigable waterways of Louisiana. As defined by the U.S. Environmental Protection Agency, an elutriate is the supernatant resulting from the vigorous 30-minute shaking of one part bottom sediment from the dredging site with four parts water (vol/vol) collected from the dredging site followed by one hour settling time and appropriate centrifugation and a 0.45-micron filtration. The elutriate studies were initiated to evaluate possible environmental effects of proposed dredging activities in selected reaches of Louisiana waterways. The waterways investigated were the Mississippi River-Gulf Outlet, Breton Sound, Mississippi River downstream from Baton Rouge, Bayou Long, Intracoastal Waterway (east and west of the Harvey Canal), Three Rivers area, Ouachita River, Barataria Bay, Houma Navigation Canal, Atchafalaya Bay (Ship Channel), Berwick Bay, Intracoastal Waterway (Port Allen to Morgan City), Petite Anse area, and Calcasieu River and Ship Channel. The Geological Survey collected 227 samples of native water and bed (bottom) material from 130 different sites. These samples (as well as elutriates prepared from mixtures of native water and bed material) were analyzed for selected metal, pesticide, nutrient, and organic constituents. An additional 116 bed samples collected at 58 sites were analyzed for selected pesticides; and 4 additional native-water samples from 2 sites were analyzed for selected metal pesticide, nutrient, and organic constituents. (Woodard-USGS)

  9. Using Absolute Humidity and Radiochemical Analyses of Water Vapor Samples to Correct Underestimated Atmospheric Tritium Concentrations

    SciTech Connect

    Eberhart, C.F.

    1999-06-01

    Los Alamos National Laboratory (LANL) emits a wide variety of radioactive air contaminants. An extensive ambient air monitoring network, known as AIRNET, is operated on-site and in surrounding communities to estimate radioactive doses to the public. As part of this monitoring network, water vapor is sampled continuously at more than 50 sites. These water vapor samples are collected every two weeks by absorbing the water vapor in the sampled air with silica gel and then radiochemically analyzing the water for tritium. The data have consistently indicated that LANL emissions cause a small, but measurable impact on local concentrations of tritium. In early 1998, while trying to independently verify the presumed 100% water vapor collection efficiency, the author found that this efficiency was normally lower and reached a minimum of 10 to 20% in the middle of summer. This inefficient collection was discovered by comparing absolute humidity (g/m{sup 3}) calculated from relative humidity and temperature to the amount of water vapor collected by the silica gel per cubic meter of air sampled. Subsequent experiments confirmed that the elevated temperature inside the louvered housing was high enough to reduce the capacity of the silica gel by more than half. In addition, their experiments also demonstrated that, even under optimal conditions, there is not enough silica gel present in the sampling canister to absorb all of the moisture during the higher humidity periods. However, there is a solution to this problem. Ambient tritium concentrations have been recalculated by using the absolute humidity values and the tritium analyses. These recalculated tritium concentrations were two to three times higher than previously reported. Future tritium concentrations will also be determined in the same manner. Finally, the water vapor collection process will be changed by relocating the sampling canister outside the housing to increase collection efficiency and, therefore

  10. Comments Received on Proposed Additions to West Virginia's 2014 List of Impaired Waters

    EPA Pesticide Factsheets

    Comments submitted from the public during the public comment period for EPA's partial approval-partial disapproval and proposed additions to West Virginia's 2014 Section 303(d) List of Impaired Waters.

  11. Water column and bed-sediment core samples collected from Brownlee Reservoir near Oxbow, Oregon, 2012

    USGS Publications Warehouse

    Fosness, Ryan L.; Naymik, Jesse; Hopkins, Candice B.; DeWild, John F.

    2013-01-01

    The U.S. Geological Survey, in cooperation with Idaho Power Company, collected water-column and bed-sediment core samples from eight sites in Brownlee Reservoir near Oxbow, Oregon, during May 5–7, 2012. Water-column and bed-sediment core samples were collected at each of the eight sites and analyzed for total mercury and methylmercury. Additional bed-sediment core samples, collected from three of the eight sites, were analyzed for pesticides and other organic compounds, trace metals, and physical characteristics, such as particle size. Total mercury and methylmercury were detected in each of the water column and bed-sediment core samples. Only 17 of the 417 unique pesticide and organic compounds were detected in bed-sediment core samples. Concentrations of most organic wastewater compounds detected in bed sediment were less than the reporting level. Trace metals detected were greater than the reporting level in all the bed-sediment core samples submitted for analysis. The particle size distribution of bed-sediment core samples was predominantly clay mixed with silt.

  12. Long-term nitrogen additions and the intrinsic water-use efficiency of boreal Scots pine.

    NASA Astrophysics Data System (ADS)

    Marshall, John; Wallin, Göran; Linder, Sune; Lundmark, Tomas; Näsholm, Torgny

    2015-04-01

    Nitrogen fertilization nearly always increases productivity in boreal forests, at least in terms of wood production, but it is unclear how. In a mature (80 yrs. old) Scots pine forest in northern Sweden, we tested the extent to which nitrogen fertilization increased intrinsic photosynthetic water-use efficiency. We measured δ13C both discretely, in biweekly phloem sampling, and continuously, by monitoring of bole respiration. The original experiment was designed as a test of eddy covariance methods and is not therefore strictly replicated. Nonetheless, we compared phloem contents among fifteen trees from each plot and stem respiration from four per plot. The treatments included addition of 100 kg N/ha for eight years and a control. Phloem contents have the advantage of integrating over the whole canopy and undergoing complete and rapid turnover. Their disadvantage is that some have observed isotopic drift with transport down the length of the stem, presumably as a result of preferential export and/or reloading. We also measured the isotopic composition of stem respiration from four trees on each plot using a Picarro G1101-I CRDS attached to the vent flow from a continuous gas-exchange system. We detected consistent differences in δ13C between the treatments in phloem contents. Within each treatment, the phloem δ13C was negatively correlated with antecedent temperature (R2= 0.65) and no other measured climate variable. The isotopic composition of stem CO2 efflux will be compared to that of phloem contents. However, when converted to intrinsic water-use efficiency, the increase amounted to only about 4%. This is a small relative to the near doubling in wood production. Although we were able to detect a clear and consistent increase in water-use efficiency with N-fertilization, it constitutes but a minor cause of the observed increase in wood production.

  13. THE PERSISTENCE OF MYCOBACTERIUM AVIUM IN A DRINKING WATER SYSTEM AFTER THE ADDITION OF FILTRATION

    EPA Science Inventory

    Drinking water is increasingly recognized as a major source of pathogenic nontuberculous mycobacteria (NTM) associated with human infection. Our goal was to determine if the prevalence of NTM would decrease after the addition of filtration treatment to an unfiltered surface water...

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

    DTIC Science & Technology

    2016-07-01

    ARMY CORPS OF ENGINEERS Additional Steps Needed for Review and Revision of Water Control Manuals Report to...Revision of Water Control Manuals What GAO Found According to U.S. Army Corps of Engineers (Corps) officials, the agency conducts ongoing, informal...reviews of selected water control manuals and has revised some of them, but the extent of the reviews and revisions is unclear because they are not

  15. Rain water transport and storage in a model sandy soil with hydrogel particle additives.

    PubMed

    Wei, Y; Durian, D J

    2014-10-01

    We study rain water infiltration and drainage in a dry model sandy soil with superabsorbent hydrogel particle additives by measuring the mass of retained water for non-ponding rainfall using a self-built 3D laboratory set-up. In the pure model sandy soil, the retained water curve measurements indicate that instead of a stable horizontal wetting front that grows downward uniformly, a narrow fingered flow forms under the top layer of water-saturated soil. This rain water channelization phenomenon not only further reduces the available rain water in the plant root zone, but also affects the efficiency of soil additives, such as superabsorbent hydrogel particles. Our studies show that the shape of the retained water curve for a soil packing with hydrogel particle additives strongly depends on the location and the concentration of the hydrogel particles in the model sandy soil. By carefully choosing the particle size and distribution methods, we may use the swollen hydrogel particles to modify the soil pore structure, to clog or extend the water channels in sandy soils, or to build water reservoirs in the plant root zone.

  16. 49 CFR 199.111 - Retention of samples and additional testing.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... request, the sample may be discarded following the end of the 365-day period. (b) If the medical review officer (MRO) determines there is no legitimate medical explanation for a confirmed positive test result... and Human Services. The operator may require the employee to pay in advance the cost of shipment...

  17. Toward a mechanistic understanding of the effect of biochar addition on soil water retention

    NASA Astrophysics Data System (ADS)

    Yi, S.; Chang, N.; Guo, M.; Imhoff, P. T.

    2014-12-01

    Biochar (BC) is a carbon-rich product produced by thermal degradation of biomass in an oxygen-free environment, whose application to sediment is said to improve water retention. However, BC produced from different feedstocks and pyrolyzed at different temperatures have distinct properties, which may alter water retention in ways difficult to predict a priori. Our goal is to develop a mechanistic understanding of BC addition on water retention by examining the impact of BC from two feedstocks, poultry litter (PL) and hardwood (HW), on the soil-water retention curves (SWRC) of a uniform sand and a sandy loam (SL). For experiments with sand, BC and sand were sieved to the same particle size (~ 0.547 mm) to minimize effects of BC addition on particle size distribution. Experiments with SL contained the same sieved BC. PL and HW bicohars were added at 2 and 7% (w/w), and water retention was measured from 0 to -4.38 × 106 cm-H2O. Both BCs increased porosities for sand and SL, up to 39 and 13% for sand and SL, respectively, with 7% HW BC addition. The primary cause for these increases was the internal porosity of BC particles. While the matric potential for air-entry was unchanged with BC addition, BC amendment increased water retention for sand and SL in the capillary region (0 to -15,000 cm-H2O) by an average of 26 and 33 % for 7% PL and HW BC in sand, respectively, but only 7 and 14 % for 7% PL and HW BC in SL. The most dramatic influence of BC amendment on water retention occurred in the adsorption region (< -15,000 cm-H2O), where water retention increased by a factor of 11 and 22 for 7% PL and HW BC in sand, respectively, but by 140 and 190 % for 7% PL and HW BC in SL, respectively. The impact of BC on water retention in these sediments is explained primarily by the additional surface area and internal porosity of PL and HW BC particles. van Genuchten (VG) models were fitted to the water retention data. For SL where the impact of BC addition on water retention was

  18. Rapid detection of Naegleria fowleri in water distribution pipeline biofilms and drinking water samples.

    PubMed

    Puzon, Geoffrey J; Lancaster, James A; Wylie, Jason T; Plumb, Iason J

    2009-09-01

    Rapid detection of pathogenic Naegleria fowler in water distribution networks is critical for water utilities. Current detection methods rely on sampling drinking water followed by culturing and molecular identification of purified strains. This culture-based method takes an extended amount of time (days), detects both nonpathogenic and pathogenic species, and does not account for N. fowleri cells associated with pipe wall biofilms. In this study, a total DNA extraction technique coupled with a real-time PCR method using primers specific for N. fowleri was developed and validated. The method readily detected N. fowleri without preculturing with the lowest detection limit for N. fowleri cells spiked in biofilm being one cell (66% detection rate) and five cells (100% detection rate). For drinking water, the detection limit was five cells (66% detection rate) and 10 cells (100% detection rate). By comparison, culture-based methods were less sensitive for detection of cells spiked into both biofilm (66% detection for <10 cells) and drinking water (0% detection for <10 cells). In mixed cultures of N. fowleri and nonpathogenic Naegleria, the method identified N. fowleri in 100% of all replicates, whereastests with the current consensus primers detected N. fowleri in only 5% of all replicates. Application of the new method to drinking water and pipe wall biofilm samples obtained from a distribution network enabled the detection of N. fowleri in under 6 h, versus 3+ daysforthe culture based method. Further, comparison of the real-time PCR data from the field samples and the standard curves enabled an approximation of N. fowleri cells in the biofilm and drinking water. The use of such a method will further aid water utilities in detecting and managing the persistence of N. fowleri in water distribution networks.

  19. Influence of various water quality sampling strategies on load estimates for small streams

    USGS Publications Warehouse

    Robertson, D.M.; Roerish, E.D.

    1999-01-01

    Extensive streamflow and water quality data from eight small streams were systematically subsampled to represent various water-quality sampling strategies. The subsampled data were then used to determine the accuracy and precision of annual load estimates generated by means of a regression approach (typically used for big rivers) and to determine the most effective sampling strategy for small streams. Estimation of annual loads by regression was imprecise regardless of the sampling strategy used; for the most effective strategy, median absolute errors were ~30% based on the load estimated with an integration method and all available data, if a regression approach is used with daily average streamflow. The most effective sampling strategy depends on the length of the study. For 1-year studies, fixed-period monthly sampling supplemented by storm chasing was the most effective strategy. For studies of 2 or more years, fixed-period semimonthly sampling resulted in not only the least biased but also the most precise loads. Additional high-flow samples, typically collected to help define the relation between high streamflow and high loads, result in imprecise, overestimated annual loads if these samples are consistently collected early in high-flow events.

  20. Double water compatible molecularly imprinted polymers applied as solid-phase extraction sorbent for selective preconcentration and determination of triazines in complicated water samples.

    PubMed

    Xu, Shoufang; Lu, Hongzhi; Chen, Lingxin

    2014-07-11

    In the present work, double water compatible molecularly imprinted polymers (DWC-MIPs) with water compatible core and hydrophilic polymer brushes were prepared by reversible addition-fragmentation chain transfer precipitate polymerization (RAFTPP) and applied as solid-phase extraction (SPE) sorbent for selective preconcentration and specific recognition of triazines in water samples. The DWC-MIPs employed as SPE sorbent presented much higher extraction efficiency for four triazines in aqueous media based on the double water compatible property. The validated method was also successfully applied to tap water and river water sample analysis, and satisfactory recoveries were attained, such as 69.2-95.4% with the precision of 1.59-3.94% for four triazines at 100μgL(-1). The DWC-MIPs-SPE proves to be a highly effective cleanup and enrichment method for simultaneous separation and sensitive determination of triazines in complicated water samples.

  1. Issues concerning spectral analysis of water samples for monitoring and treatment of public water resources.

    PubMed

    Lee, M; Lambrakos, S G; Yapijakis, C; Huang, L; Ramsey, S; Shabaev, A; Massa, L; Peak, J

    2014-01-01

    Experimental measurements conducted in the laboratory, involving hyperspectral analysis of water samples taken from public water resources, have motivated a re-evaluation of issues concerning the potential application of this type of analysis for water monitoring, treatment and evaluation prior to filtration. One issue concerns hyperspectral monitoring of contaminants with respect to types and relative concentrations. This implies a need to better understand the statistical profiles of water contaminants in terms of spatial-temporal distributions of electromagnetic absorption spectra ranging from the ultraviolet to infrared, which are associated with specific water resources. This issue also implies the need to establish correlations between hyperspectral signatures and types of contaminants to be found within specific water resources. Another issue concerns the use of absorption spectra to determine changes in chemical and physical characteristics of contaminants after application of water treatments, in order to determine levels of toxicity with respect to the environment. This paper presents a prototype spectral analysis showing various aspects relevant to water monitoring and discusses the use of basic theory for the interpretation of spectral features associated with water contaminants, as well as discussing inverse analysis of hyperspectral measurements.

  2. Liquid Water from First Principles: Validation of Different Sampling Approaches

    SciTech Connect

    Mundy, C J; Kuo, W; Siepmann, J; McGrath, M J; Vondevondele, J; Sprik, M; Hutter, J; Parrinello, M; Mohamed, F; Krack, M; Chen, B; Klein, M

    2004-05-20

    A series of first principles molecular dynamics and Monte Carlo simulations were carried out for liquid water to assess the validity and reproducibility of different sampling approaches. These simulations include Car-Parrinello molecular dynamics simulations using the program CPMD with different values of the fictitious electron mass in the microcanonical and canonical ensembles, Born-Oppenheimer molecular dynamics using the programs CPMD and CP2K in the microcanonical ensemble, and Metropolis Monte Carlo using CP2K in the canonical ensemble. With the exception of one simulation for 128 water molecules, all other simulations were carried out for systems consisting of 64 molecules. It is found that the structural and thermodynamic properties of these simulations are in excellent agreement with each other as long as adiabatic sampling is maintained in the Car-Parrinello molecular dynamics simulations either by choosing a sufficiently small fictitious mass in the microcanonical ensemble or by Nos{acute e}-Hoover thermostats in the canonical ensemble. Using the Becke-Lee-Yang-Parr exchange and correlation energy functionals and norm-conserving Troullier-Martins or Goedecker-Teter-Hutter pseudopotentials, simulations at a fixed density of 1.0 g/cm{sup 3} and a temperature close to 315 K yield a height of the first peak in the oxygen-oxygen radial distribution function of about 3.0, a classical constant-volume heat capacity of about 70 J K{sup -1} mol{sup -1}, and a self-diffusion constant of about 0.1 Angstroms{sup 2}/ps.

  3. A first screening and risk assessment of pharmaceuticals and additives in personal care products in waste water, sludge, recipient water and sediment from Faroe Islands, Iceland and Greenland.

    PubMed

    Huber, Sandra; Remberger, Mikael; Kaj, Lennart; Schlabach, Martin; Jörundsdóttir, Hrönn Ó; Vester, Jette; Arnórsson, Mímir; Mortensen, Inge; Schwartson, Richard; Dam, Maria

    2016-08-15

    A screening of a broad range of pharmaceuticals and additives in personal care products (PPCPs) in sub-arctic locations of the Faroe Islands (FO), Iceland (IS) and Greenland (GL) was conducted. In total 36 pharmaceuticals including some metabolites, and seven additives in personal care products were investigated in influent and effluent waters as well as sludge of waste water treatment plants (WWTPs) and in water and sediment of recipients. Concentrations and distribution patterns for PPCPs discharged via sewage lines (SLs) to the marine environment were assessed. Of the 36 pharmaceuticals or metabolites analysed 33 were found close to or above the limit of detection (LOD) in all or a part of the samples. All of the seven investigated additives in personal care products were detected above the LOD. Some of the analysed PPCPs occurred in every or almost every sample. Among these were diclofenac, ibuprofen, lidocaine, naproxen, metformin, citalopram, venlafaxine, amiloride, furosemide, metoprolol, sodium dodecyl sulphate (SDS) and cetrimonium salt (ATAC-C16). Additionally, the study encompasses ecotoxicological risk assessment of 2/3 of the analysed PPCPs in recipient and diluted effluent waters. For candesartan only a small margin to levels with inacceptable risks was observed in diluted effluent waters at two locations (FO). Chronical risks for aquatic organisms staying and/or living around WWTP effluent pipe-outlets were indicated for 17β-estradiol and estriol in the three countries. Additives in PCPs were found to pose the largest risk to the aquatic environment. The surfactants CAPB and ATAC-C16 were found in concentrations resulting in risk factors up to 375 for CAPB and 165 for ATAC-C16 in recipients for diluted effluents from Iggia, Nuuk (GL) and Torshavn (FO) respectively. These results demonstrates a potentially high ecological risk stemming from discharge of surfactants as used in household and industrial detergents as well as additives in personal care

  4. Distribution of Cryptosporidium Genotypes in Storm Event Water Samples from Three Watersheds in New York

    PubMed Central

    Jiang, Jianlin; Alderisio, Kerri A.; Xiao, Lihua

    2005-01-01

    To assess the source and public health significance of Cryptosporidium oocyst contamination in storm runoff, a PCR-restriction fragment length polymorphism technique based on the small-subunit rRNA gene was used in the analysis of 94 storm water samples collected from the Malcolm Brook and N5 stream basins in New York over a 3-year period. The distribution of Cryptosporidium in this study was compared with the data obtained from 27 storm water samples from the Ashokan Brook in a previous study. These three watersheds represented different levels of human activity. Among the total of 121 samples analyzed from the three watersheds, 107 were PCR positive, 101 of which (94.4%) were linked to animal sources. In addition, C. hominis (W14) was detected in six samples collected from the Malcolm Brook over a 2-week period. Altogether, 22 Cryptosporidium species or genotypes were found in storm water samples from these three watersheds, only 11 of which could be attributed to known species/groups of animals. Several Cryptosporidium spp. were commonly found in these three watersheds, including the W1 genotype from an unknown animal source, the W4 genotype from deer, and the W7 genotype from muskrats. Some genotypes were found only in a particular watershed. Aliquots of 113 samples were also analyzed by the Environmental Protection Agency (EPA) Method 1623; 63 samples (55.7%) were positive for Cryptosporidium by microscopy, and 39 (78%) of the 50 microscopy-negative samples were positive by PCR. Results of this study demonstrate that molecular techniques can complement traditional detection methods by providing information on the source of contamination and the human-infective potential of Cryptosporidium oocysts found in water. PMID:16085835

  5. Evaluation of selected information on splitting devices for water samples

    USGS Publications Warehouse

    Capel, P.D.; Larson, S.J.

    1996-01-01

    Four devices for splitting water samples into representative aliquots are used by the U.S. Geological Survey's Water Resources Division. A thorough evaluation of these devices (14-liter churn, 8-liter churn, plastic cone, and Teflon cone) encompasses a wide variety of concerns, based on both chemical and physical considerations. This report surveys the existing data (as of April 1994) on cleaning efficiency and splitting capability of these devices and presents the data in a systematic framework for evaluation. From the existing data, some of these concerns are adequately or partially addressed, but the majority of concerns could not be addressed because of the lack of data. In general, the existing cleaning and transport protocols are adequate at the milligram per liter level, but the adequacy is largely unknown for trace elements and organic chemicals at lower concen- trations. The existing data indicate that better results are obtained when the splitters are cleaned in the laboratory rather than in the field. Two conclusions that can be reached on the splitting capability of solids are that more work must be done with all four devices to characterize and quantify their limitations and range of usefulness, and that the 14-liter churn (and by association, the 8-liter churn) is not useful in obtaining representative splits of sand-sized particles.

  6. Nitrogen addition and clonal integration alleviate water stress of dependent ramets of Indocalamus decorus under heterogeneous soil water environment

    PubMed Central

    Guo, Zi-Wu; Hu, Jun-Jing; Chen, Shuang-Lin; Li, Ying-Chun; Yang, Qing-Ping; Cai, Han-Jiang

    2017-01-01

    Water and nitrogen are two of the most important factors for plant growth and development. However, little is known about effects of N on water translocation between connected bamboo ramets. We performed experiment connected Indocalamus decorus ramets in adjacent pots with different soil water contents and three N levels. We determined antioxidase activities, concentration of osmotic adjustment products, O2·−, MDA and photosynthetic pigments, and electrolyte leakage rate in paired unit. When N supply to supporting ramets increased, their electrolyte leakage rates and contents of O2·− and MDA significantly increased, while antioxidase activities and contents of osmotic adjustment products and photosynthetic pigments in connected dependent ramets increased markedly as their electrolyte leakage rates and contents of O2·− and MDA decreased greatly. When N addition to dependent ramets increased, antioxidant enzyme activity and contents of osmotic adjustment products and photosynthetic pigments decreased in both ramets, but electrolyte leakage rates and O2·− and MDA contents increased significantly. Therefore, N addition to either supporting or dependent ramets can improve water integration among I. decorus ramets. N addition to supporting ramets promotes water translocation and alleviates water stress of dependent ramets, but N addition to dependent ramets exacerbates drought stress damage to dependent ramets. PMID:28295023

  7. Nitrogen addition and clonal integration alleviate water stress of dependent ramets of Indocalamus decorus under heterogeneous soil water environment.

    PubMed

    Guo, Zi-Wu; Hu, Jun-Jing; Chen, Shuang-Lin; Li, Ying-Chun; Yang, Qing-Ping; Cai, Han-Jiang

    2017-03-15

    Water and nitrogen are two of the most important factors for plant growth and development. However, little is known about effects of N on water translocation between connected bamboo ramets. We performed experiment connected Indocalamus decorus ramets in adjacent pots with different soil water contents and three N levels. We determined antioxidase activities, concentration of osmotic adjustment products, O2·(-), MDA and photosynthetic pigments, and electrolyte leakage rate in paired unit. When N supply to supporting ramets increased, their electrolyte leakage rates and contents of O2·(-) and MDA significantly increased, while antioxidase activities and contents of osmotic adjustment products and photosynthetic pigments in connected dependent ramets increased markedly as their electrolyte leakage rates and contents of O2·(-) and MDA decreased greatly. When N addition to dependent ramets increased, antioxidant enzyme activity and contents of osmotic adjustment products and photosynthetic pigments decreased in both ramets, but electrolyte leakage rates and O2·(-) and MDA contents increased significantly. Therefore, N addition to either supporting or dependent ramets can improve water integration among I. decorus ramets. N addition to supporting ramets promotes water translocation and alleviates water stress of dependent ramets, but N addition to dependent ramets exacerbates drought stress damage to dependent ramets.

  8. A water quality monitoring network design methodology for the selection of critical sampling points: Part I.

    PubMed

    Strobl, R O; Robillard, P D; Shannon, R D; Day, R L; McDonnell, A J

    2006-01-01

    The principal instrument to temporally and spatially manage water resources is a water quality monitoring network. However, to date in most cases, there is a clear absence of a concise strategy or methodology for designing monitoring networks, especially when deciding upon the placement of sampling stations. Since water quality monitoring networks can be quite costly, it is very important to properly design the monitoring network so that maximum information extraction can be accomplished, which in turn is vital when informing decision-makers. This paper presents the development of a methodology for identifying the critical sampling locations within a watershed. Hence, it embodies the spatial component in the design of a water quality monitoring network by designating the critical stream locations that should ideally be sampled. For illustration purposes, the methodology focuses on a single contaminant, namely total phosphorus, and is applicable to small, upland, predominantly agricultural-forested watersheds. It takes a number of hydrologic, topographic, soils, vegetative, and land use factors into account. In addition, it includes an economic as well as logistical component in order to approximate the number of sampling points required for a given budget and to only consider the logistically accessible stream reaches in the analysis, respectively. The methodology utilizes a geographic information system (GIS), hydrologic simulation model, and fuzzy logic.

  9. Measurement of the tritium concentration in the fractionated distillate from environmental water samples.

    PubMed

    Atkinson, Robert; Eddy, Teresa; Kuhne, Wendy; Jannik, Tim; Brandl, Alexander

    2014-09-01

    Standard procedures for the measurement of tritium in water samples often require distillation of an appropriate sample aliquot. This distillation process may result in a fractionation of tritiated water and regular light water due to the vapor pressure isotope effect, introducing either a bias or an additional contribution to the total tritium measurement uncertainty. The current study investigates the relative change in vapor pressure isotope effect in the course of the distillation process, distinguishing it from and extending previously published measurements. The separation factor as a quantitative measure of the vapor pressure isotope effect is found to assume values of 1.04 ± 0.036, 1.05 ± 0.026, and 1.07 ± 0.038, depending on the vigor of the boiling process during distillation of the sample. A lower heat setting in the experimental setup, and therefore a less vigorous boiling process, results in a larger value for the separation factor. For a tritium measurement in water samples where the first 5 mL are discarded, the tritium concentration could be underestimated by 4-7%.

  10. Supplement to the UMTRA Project water sampling and analysis plan, Riverton, Wyoming

    SciTech Connect

    1995-09-01

    This water sampling and analysis plan (WSAP) supplement supports the regulatory and technical basis for water sampling at the Riverton, Wyoming, Uranium Mill Tailings Remedial Action (UMTRA) Project site, as defined in the 1994 WSAP document for Riverton (DOE, 1994). Further, the supplement serves to confirm the Project`s present understanding of the site relative to the hydrogeology and contaminant distribution as well as the intent to continue to use the sampling strategy as presented in the 1994 WSAP document for Riverton. Ground water and surface water monitoring activities are derived from the US Environmental Protection Agency regulations in 40 CFR Part 192 and 60 FR 2854. Sampling procedures are guided by the UMTRA Project standard operating procedures (JEG, n.d.), the Technical Approach Document (DOE, 1989), and the most effective technical approach for the site. Additional site-specific documents relevant to the Riverton site are the Riverton Baseline Risk Assessment (BLRA) (DOE, 1995a) and the Riverton Site Observational Work Plan (SOWP) (DOE, 1995b).

  11. [Analysis of lead in unknown samples based on the standard addition method using laser induced breakdown spectroscopy].

    PubMed

    Fang, Li; Zhao, Nan-jing; Meng, De-shuo; Yuan, Jing; Tang, Jie; Wang, Yin; Yu, Yang; Ma, Ming-jun; Hu, Li; Zhang, Da-hai; Xiao, Xue; Wang, Yu; Liu, Jian-guo; Liu, Wen-qing

    2015-01-01

    The standard addition method with laser induced breakdown spectroscopy was used to analyze an unknown sample taken from a lead battery factory. the matrix influence on the results was effectively avoided when the external or internal standard method was used, and the pretreatment of samples was simple and quick. The Nd ' YAG pulse laser with wavelength 1 064 nm was used as the excitation source. The echelle spectroscopy with high resolution and wide spectral range was used as the spectral separation device, and the intensified charge coupled device (ICCD) as the spectral detection device in the experiment. The characteristic line at 405. 78 nrn was chosen as the analysis line to measure Pb concentration. Fe I : 404. 58 line was chosen as the internal standard. Pre-experiment was carried out to confirm the appropriate condition. Under the laser energy of 128. 5 mJ, the delay time of 2. 5 tps, and the gate width of 3 ps, it was determined that with the addition of Pb to the sample in the range of 0 and 25 000 mg . kg-1, there wasn't self-absorption. There was a good linear relationship between the intensity of the spectral line of 405. 78 nm and the addition of Pb. The appropriate concentration of Pb added into the sample for analysis was determined by this series of samples. On this basis, four samples were prepared with three parallel samples for each sample in order to verify the repeatability and reliability of the method, i. e. 5 000, 10 000, 15 000, 20 000 mg . kg-1 Pb was added into the original sample. The results were compared with the result of ICP-MS. The twelve samples' relative errors were between -24. 6% and 17. 6%. The average result was 43 069 mg . kg-1 with the relative error -2. 44%.

  12. Extraction of pesticides in water samples using vortex-assisted liquid-liquid microextraction.

    PubMed

    Jia, Chunhong; Zhu, Xiaodan; Wang, Jihua; Zhao, Ercheng; He, Min; Chen, Li; Yu, Pingzhong

    2010-09-10

    A simple solvent microextraction method termed vortex-assisted liquid-liquid microextraction (VALLME) coupled with gas chromatography micro electron-capture detector (GC-microECD) has been developed and used for the pesticide residue analysis in water samples. In the VALLME method, aliquots of 30 microL toluene used as extraction solvent were directly injected into a 25 mL volumetric flask containing the water sample. The extraction solvent was dispersed into the water phase under vigorously shaking with the vortex. The parameters affecting the extraction efficiency of the proposed VALLME such as extraction solvent, vortex time, volumes of extraction solvent and salt addition were investigated. Under the optimum condition, enrichment factors (EFs) in a range of 835-1115 and limits of detection below 0.010 microg L(-1) were obtained for the determination of target pesticides in water. The calculated calibration curves provide high levels of linearity yielding correlation coefficients (r(2)) greater than 0.9958 with the concentration level ranged from 0.05 to 2.5 microg L(-1). Finally, the proposed method has been successfully applied to the determination of pesticides from real water samples and acceptable recoveries over the range of 72-106.3% were obtained.

  13. Improvement of organics removal by bio-ceramic filtration of raw water with addition of phosphorus.

    PubMed

    Sang, Junqiang; Zhang, Xihui; Li, Lingzhi; Wang, Zhansheng

    2003-11-01

    The purpose of this study was to investigate the effect of phosphorus addition on biological pretreatment of raw water. Experiments were conducted in pilot-scale bio-ceramic filters with raw water from a reservoir located in Beijing, China. The results demonstrated that phosphorus was the limiting nutrient for bacterial growth in the raw water investigated in this study. The measured values of bacterial regrowth potential (BRP) and biodegradable dissolved organic carbon (BDOC) of the raw water increased by 50-65% and 30-40% with addition of 50 microg of PO4(3-)-PL(-1), respectively. Addition of 25 microg of PO4(3-)-PL(-1) to the influent of bio-ceramic filter enhanced the percent removal of organics by 4.6, 5.7 and 15 percentage points in terms of COD(Mn), TOC and BDOC, respectively. Biomass in terms of phospholipid content increased by 13-22% and oxygen uptake rate (OUR) increased by 35-45%. The ratio of C:P for bacteria growth was 100:1.6 for the raw water used in this study. Since change of phosphorus concentrations can influence the performance of biological pretreatment and the biological stability of drinking water, this study is of substantial significance for waterworks in China. The role of phosphorus in biological processes of drinking water should deserve more attention.

  14. Sampling and analysis for radon-222 dissolved in ground water and surface water

    USGS Publications Warehouse

    DeWayne, Cecil L.; Gesell, T.F.

    1992-01-01

    Radon-222 is a naturally occurring radioactive gas in the uranium-238 decay series that has traditionally been called, simply, radon. The lung cancer risks associated with the inhalation of radon decay products have been well documented by epidemiological studies on populations of uranium miners. The realization that radon is a public health hazard has raised the need for sampling and analytical guidelines for field personnel. Several sampling and analytical methods are being used to document radon concentrations in ground water and surface water worldwide but no convenient, single set of guidelines is available. Three different sampling and analytical methods - bubbler, liquid scintillation, and field screening - are discussed in this paper. The bubbler and liquid scintillation methods have high accuracy and precision, and small analytical method detection limits of 0.2 and 10 pCi/l (picocuries per liter), respectively. The field screening method generally is used as a qualitative reconnaissance tool.

  15. Determination of radon and radium concentrations in drinking water samples around the city of Kutahya.

    PubMed

    Sahin, Latife; Cetinkaya, Hakan; Murat Saç, Müslim; Içhedef, Mutlu

    2013-08-01

    The concentration of radium and radon has been determined in drinking water samples collected from various locations of Kutahya city, Turkey. The water samples are taken from public water sources and tap water, with the collector chamber method used to measure the radon and radium concentration. The radon concentration ranges between 0.1 and 48.6±1.7 Bq l(-1), while the radium concentration varies from a minimum detectable activity of <0.02-0.7±0.2 Bq l(-1) in Kutahya city. In addition to the radon and radium levels, parameters such as pH, conductivity and temperature of the water, humidity, pressure, elevation and the coordinates of the sampling points have also been measured and recorded. The annual effective dose from radon and radium due to typical water usage has been calculated. The resulting contribution to the annual effective dose due to radon ingestion varies between 0.3 and 124.2 μSv y(-1); the contribution to the annual effective dose due to radium ingestion varies between 0 and 143.3 μSv y(-1); the dose contribution to the stomach due to radon ingestion varies between 0.03 and 14.9 μSv y(-1). The dose contribution due to radon inhalation ranges between 0.3 and 122.5 μSv y(-1), assuming a typical transfer of radon in water to the air. For the overwhelming majority of the Kutahya population, it is determined that the average radiation exposure from drinking water is less than 73.6 µSv y(-1).

  16. Effects of water and nitrogen addition on species turnover in temperate grasslands in northern China.

    PubMed

    Xu, Zhuwen; Wan, Shiqiang; Ren, Haiyan; Han, Xingguo; Li, Mai-He; Cheng, Weixin; Jiang, Yong

    2012-01-01

    Global nitrogen (N) deposition and climate change have been identified as two of the most important causes of current plant diversity loss. However, temporal patterns of species turnover underlying diversity changes in response to changing precipitation regimes and atmospheric N deposition have received inadequate attention. We carried out a manipulation experiment in a steppe and an old-field in North China from 2005 to 2009, to test the hypothesis that water addition enhances plant species richness through increase in the rate of species gain and decrease in the rate of species loss, while N addition has opposite effects on species changes. Our results showed that water addition increased the rate of species gain in both the steppe and the old field but decreased the rates of species loss and turnover in the old field. In contrast, N addition increased the rates of species loss and turnover in the steppe but decreased the rate of species gain in the old field. The rate of species change was greater in the old field than in the steppe. Water interacted with N to affect species richness and species turnover, indicating that the impacts of N on semi-arid grasslands were largely mediated by water availability. The temporal stability of communities was negatively correlated with rates of species loss and turnover, suggesting that water addition might enhance, but N addition would reduce the compositional stability of grasslands. Experimental results support our initial hypothesis and demonstrate that water and N availabilities differed in the effects on rate of species change in the temperate grasslands, and these effects also depend on grassland types and/or land-use history. Species gain and loss together contribute to the dynamic change of species richness in semi-arid grasslands under future climate change.

  17. Effect of addition of coconut water (Cocos nucifera) to the freezing media on post-thaw viability of boar sperm.

    PubMed

    Bottini-Luzardo, María; Centurión-Castro, Fernando; Alfaro-Gamboa, Militza; Aké-López, Ricardo; Herrera-Camacho, José

    2013-01-01

    The aims of this experiment were to evaluate the addition of coconut water in natura to the freezing media, compare the effect of deionized water vs filtered water of coconut over the post-thaw seminal characteristics, and evaluate the effect of the deionized water and in natura coconut water on the seminal characteristics of boar sperm at different post-thaw times. Thirty-four ejaculates were used divided in three aliquots which received one of the following treatments (T): T1, LEY (bidistilled water, lactose, and egg yolk) and LEYGO (LEY + glycerol and Orvus ET paste); T2, LEY(A) (coconut deionized water, lactose, and egg yolk)-LEYGO(A); and T3, LEY(B) (in natura coconut water, lactose, and egg yolk)-LEYGO(B). Samples of boar semen were frozen according to the Westendorf method, thawed at 38°C, and evaluated at three incubation times (0, 30, and 60 min). Seminal characteristics assessed were motility (Mot), acrosomal integrity (AInt), membrane integrity (MInt), and mitochondrial activity (MAct). T1 showed a higher percentage of viable sperm than T3 (Mot 36.5 vs 5.4 %, AInt 61.8 vs 41.2 %, MInt 50.4 vs 41.3 %, and MAct 56.9 vs 50.5 %). T2 kept a higher percentage of viable sperm at all incubation times. In natura coconut water showed a detrimental effect over the viability of the frozen-thawed boar semen. Deionized coconut water improved the boar semen viability post-thaw, outperforming results of in natura coconut water.

  18. Stress corrosion cracking of α-brass in waters with and without additions

    NASA Astrophysics Data System (ADS)

    Parkins, R. N.; Rangel, C. M.; Yu, J.

    1985-09-01

    Slow strain rate stress corrosion tests on a 0.032 pct As brass in SO2 solutions of increasing dilution eventually resulted in tests being carried out in various waters which were also found to promote cracking. A 0.002 pet As brass was also found to be susceptible to cracking in deionized water, but in brackish water or an acidified sulfate solution this brass did not display the stress corrosion cracking observed in these more aggressive solutions by the higher As brass. The addition of arsenite to distilled water or arsenate to deionized water in sufficient amounts effectively inhibited the cracking observed at controlled potentials or open circuit in these waters without the As additions. The results are interpreted as indicative of dezincification being involved in these various environments that promoted cracking, but the extent of the dezincification plays an important role in determining whether or not cracking occurs, those additions leading to rapid and massive dezincification involving redeposition of dissolved Cu not being conducive to cracking.

  19. Impact of orthophosphate addition on biofilm development in drinking water distribution systems.

    PubMed

    Gouider, Mbarka; Bouzid, Jalel; Sayadi, Sami; Montiel, Antoine

    2009-08-15

    The contamination of the water distribution network results from fixed bacteria multiplication (biofilm) on the water pipe walls, followed by their detachment and their transport in the circulating liquid. The presence of biofilms in distribution networks can result in numerous unwanted problems for the user such as microbial contamination of the distributed water and deterioration of the network (bio-corrosion). For old networks, lead-containing plumbings can be a serious cause of worry for the consumer owing to the release of lead ions in the circulating water. Among the solutions considered to reduce the presence of lead in drinking water, the addition of orthophosphates constitutes an interesting alternative. However, the added orthophosphate may cause--even at low doses--additional microbial growth. The main objective of this study was to evaluate the impact of the orthophosphate treatment on the biofilm development in the water supplied by the Joinville-le-Pont water treatment plant (Eau de Paris, France). For this purpose, a laboratory pilot plant was devised and connected to the considered water network. Two quantification methods for monitoring the biofilm formation were used: the enumeration on R2A agar and the determination of proteins. For the biofilm detachment operation, an optimization of the rinsing step was firstly conducted in order to distinguish between free and fixed biomass. The data obtained showed that there was a linear relation between both quantification methods. They also showed that, for the tested water, the bacterial densities were not affected by orthophosphate addition at a treatment rate of 1mg PO(4)(3-)/L.

  20. Effects of water and nitrogen addition on ecosystem carbon exchange in a meadow steppe.

    PubMed

    Wang, Yunbo; Jiang, Qi; Yang, Zhiming; Sun, Wei; Wang, Deli

    2015-01-01

    A changing precipitation regime and increasing nitrogen deposition are likely to have profound impacts on arid and semiarid ecosystem C cycling, which is often constrained by the timing and availability of water and nitrogen. However, little is known about the effects of altered precipitation and nitrogen addition on grassland ecosystem C exchange. We conducted a 3-year field experiment to assess the responses of vegetation composition, ecosystem productivity, and ecosystem C exchange to manipulative water and nitrogen addition in a meadow steppe. Nitrogen addition significantly stimulated aboveground biomass and net ecosystem CO2 exchange (NEE), which suggests that nitrogen availability is a primary limiting factor for ecosystem C cycling in the meadow steppe. Water addition had no significant impacts on either ecosystem C exchange or plant biomass, but ecosystem C fluxes showed a strong correlation with early growing season precipitation, rather than whole growing season precipitation, across the 3 experimental years. After we incorporated water addition into the calculation of precipitation regimes, we found that monthly average ecosystem C fluxes correlated more strongly with precipitation frequency than with precipitation amount. These results highlight the importance of precipitation distribution in regulating ecosystem C cycling. Overall, ecosystem C fluxes in the studied ecosystem are highly sensitive to nitrogen deposition, but less sensitive to increased precipitation.

  1. Effects of Water and Nitrogen Addition on Ecosystem Carbon Exchange in a Meadow Steppe

    PubMed Central

    Wang, Yunbo; Jiang, Qi; Yang, Zhiming; Sun, Wei; Wang, Deli

    2015-01-01

    A changing precipitation regime and increasing nitrogen deposition are likely to have profound impacts on arid and semiarid ecosystem C cycling, which is often constrained by the timing and availability of water and nitrogen. However, little is known about the effects of altered precipitation and nitrogen addition on grassland ecosystem C exchange. We conducted a 3-year field experiment to assess the responses of vegetation composition, ecosystem productivity, and ecosystem C exchange to manipulative water and nitrogen addition in a meadow steppe. Nitrogen addition significantly stimulated aboveground biomass and net ecosystem CO2 exchange (NEE), which suggests that nitrogen availability is a primary limiting factor for ecosystem C cycling in the meadow steppe. Water addition had no significant impacts on either ecosystem C exchange or plant biomass, but ecosystem C fluxes showed a strong correlation with early growing season precipitation, rather than whole growing season precipitation, across the 3 experimental years. After we incorporated water addition into the calculation of precipitation regimes, we found that monthly average ecosystem C fluxes correlated more strongly with precipitation frequency than with precipitation amount. These results highlight the importance of precipitation distribution in regulating ecosystem C cycling. Overall, ecosystem C fluxes in the studied ecosystem are highly sensitive to nitrogen deposition, but less sensitive to increased precipitation. PMID:26010888

  2. GROUND WATER SAMPLING FOR VERTICAL PROFILING OF CONTAMINANTS

    EPA Science Inventory

    Accurate delineation of plume boundaries and vertical contaminant distribution are necessary in order to adequately characterize waste sites and determine remedial strategies to be employed. However, it is important to consider the sampling objectives, sampling methods, and sampl...

  3. Iron analysis in atmospheric water samples by atomic absorption spectroscopy (AAS) in water-methanol.

    PubMed

    Sofikitis, A M; Colin, J L; Desboeufs, K V; Losno, R

    2004-01-01

    To distinguish between Fe(II) and Fe(III) species in atmospheric water samples, we have adapted an analytical procedure based on the formation of a specific complex between Fe(II) and ferrozine (FZ) on a chromatographic column. After elution of Fe(III), the Fe(II) complex is recovered with water-methanol (4:1). The possibility of trace iron measurements in this complex medium by graphite-furnace atomic-absorption spectrometry has been investigated. A simplex optimization routine was required to complete the development of the analytical method.

  4. Determination of colloidal and dissolved silver in water samples using colorimetric solid-phase extraction.

    PubMed

    Hill, April A; Lipert, Robert J; Porter, Marc D

    2010-03-15

    The increase in bacterial resistance to antibiotics has led to resurgence in the use of silver as a biocidal agent in applications ranging from washing machine additives to the drinking water treatment system on the International Space Station (ISS). However, growing concerns about the possible toxicity of colloidal silver to bacteria, aquatic organisms and humans have led to recently issued regulations by the US EPA and FDA regarding the usage of silver. As part of an ongoing project, we have developed a rapid, simple method for determining total silver, both ionic (silver(I)) and colloidal, in 0.1-1mg/L aqueous samples, which spans the ISS potable water target of 0.3-0.5mg/L (total silver) and meets the US EPA limit of 0.1mg/L in drinking water. The method is based on colorimetric solid-phase extraction (C-SPE) and involves the extraction of silver(I) from water samples by passage through a solid-phase membrane impregnated with the colorimetric reagent DMABR (5-[4-(dimethylamino)benzylidene]rhodanine). Silver(I) exhaustively reacts with impregnated DMABR to form a colored compound, which is quantified using a handheld diffuse reflectance spectrophotometer. Total silver is determined by first passing the sample through a cartridge containing Oxone, which exhaustively oxidizes colloidal silver to dissolved silver(I). The method, which takes less than 2 min to complete and requires only approximately 1 mL of sample, has been validated through a series of tests, including a comparison with the ICP-MS analysis of a water sample from ISS that contained both silver(I) and colloidal silver. Potential earth-bound applications are also briefly discussed.

  5. Phosphorus Concentrations in Stream-Water and Reference Samples - An Assessment of Laboratory Comparability

    USGS Publications Warehouse

    McHale, Michael R.; McChesney, Dennis

    2007-01-01

    In 2003, a study was conducted to evaluate the accuracy and precision of 10 laboratories that analyze water-quality samples for phosphorus concentrations in the Catskill Mountain region of New York State. Many environmental studies in this region rely on data from these different laboratories for water-quality analyses, and the data may be used in watershed modeling and management decisions. Therefore, it is important to determine whether the data reported by these laboratories are of comparable accuracy and precision. Each laboratory was sent 12 samples for triplicate analysis for total phosphorus, total dissolved phosphorus, and soluble reactive phosphorus. Eight of these laboratories reported results that met comparability criteria for all samples; the remaining two laboratories met comparability criteria for only about half of the analyses. Neither the analytical method used nor the sample concentration ranges appeared to affect the comparability of results. The laboratories whose results were comparable gave consistently comparable results throughout the concentration range analyzed, and the differences among methods did not diminish comparability. All laboratories had high data precision as indicated by sample triplicate results. In addition, the laboratories consistently reported total phosphorus values greater than total dissolved phosphorus values, and total dissolved phosphorus values greater than soluble reactive phosphorus values, as would be expected. The results of this study emphasize the importance of regular laboratory participation in sample-exchange programs.

  6. Electromembrane extraction for the determination of parabens in water samples.

    PubMed

    Villar-Navarro, Mercedes; Moreno-Carballo, María Del Carmen; Fernández-Torres, Rut; Callejón-Mochón, Manuel; Bello-López, Miguel Ángel

    2016-02-01

    To our knowledge, for the first time an electromembrane extraction combined with a high-performance liquid chromatography procedure using diode-array detection has been developed for the determination of five of the most widely used parabens: ethyl 4-hydroxybenzoate, propyl 4-hydroxybenzoate, butyl 4-hydroxybenzoate, isobutyl 4-hydroxybenzoate, and benzyl 4-hydroxybenzoate. Parabens were extracted from pH 4 aqueous sample solutions with use of an Accurel® S6/2 polypropylene hollow fiber that supports a liquid membrane of 1-octanol to a pH 12 aqueous acceptor solution placed inside the lumen of the hollow fiber. An electric current of 30 V was applied over the supported liquid membrane by means of platinum wires placed in the donor and acceptor phases. Parabens were extracted in 40 min with enrichment factors in the 30-49 range. The procedure has detection limits between 0.98 and 1.43 μg L(-1). The method was applied to the determination of parabens in surface environmental waters with excellent results.

  7. Volatile organic compound matrix spike recoveries for ground- and surface-water samples, 1997-2001

    USGS Publications Warehouse

    Rowe, Barbara L.; Delzer, Gregory C.; Bender, David A.; Zogorski, John S.

    2005-01-01

    The U.S. Geological Survey's National Water-Quality Assessment (NAWQA) Program used field matrix spikes (FMSs), field matrix spike replicates (FMSRs), laboratory matrix spikes (LMSs), and laboratory reagent spikes (LRSs), in part, to assess the quality of volatile organic compound (VOC) data from water samples collected and analyzed in more than 50 of the Nation's largest river basins and aquifers (Study Units). The data-quality objectives of the NAWQA Program include estimating the extent to which variability, degradation, and matrix effects, if any, may affect the interpretation of chemical analyses of ground- and surface-water samples. In order to help meet these objectives, a known mass of VOCs was added (spiked) to water samples collected in 25 Study Units. Data within this report include recoveries from 276 ground- and surface-water samples spiked with a 25-microliter syringe with a spike solution containing 85 VOCs to achieve a concentration of 0.5 microgram per liter. Combined recoveries for 85 VOCs from spiked ground- and surface-water samples and reagent water were used to broadly characterize the overall recovery of VOCs. Median recoveries for 149 FMSs, 107 FMSRs, 20 LMSs, and 152 LRSs were 79.9, 83.3, 113.1, and 103.5 percent, respectively. Spike recoveries for 85 VOCs also were calculated individually. With the exception of a few VOCs, the median percent recoveries determined from each spike type for individual VOCs followed the same pattern as for all VOC recoveries combined, that is, listed from least to greatest recovery-FMSs, FMSRs, LRSs, and LMSs. The median recoveries for individual VOCs ranged from 63.7 percent to 101.5 percent in FMSs; 63.1 percent to 101.4 percent in FMSRs; 101.7 percent to 135.0 percent in LMSs; and 91.0 percent to 118.7 percent in LRSs. Additionally, individual VOC recoveries were compared among paired spike types, and these recoveries were used to evaluate potential bias in the method. Variability associated with field

  8. Water and a protic ionic liquid acted as refolding additives for chemically denatured enzymes.

    PubMed

    Attri, Pankaj; Venkatesu, P; Kumar, Anil

    2012-10-07

    In this communication, we present the ability of water and a protic ionic liquid, triethyl ammonium phosphate (TEAP) to act as refolding additives for the urea-induced chemical denaturated state of the two enzymes, α-chymotrypsin and succinylated Con A. We show that the enzymatic activity is regained and in certain circumstances enhanced.

  9. Water sorption of CH3- and CF3-Bis-GMA based resins with additives

    PubMed Central

    PRAKKI, Anuradha; CILLI, Renato; VIEIRA, Ian Matos; DUDUMAS, Kristina; PEREIRA, José Carlos

    2012-01-01

    Objectives To evaluate the effect of additives on the water sorption characteristics of Bis-GMA based copolymers and composites containing TEGDMA, CH3Bis-GMA or CF3Bis-GMA. Material and methods Fifteen experimental copolymers and corresponding composites were prepared combining Bis-GMA and TEGDMA, CH3Bis-GMA or CF3Bis-GMA, with aldehyde or diketone (24 and 32 mol%) totaling 30 groups. For composites, barium aluminosilicate glass and pyrogenic silica was added to comonomer mixtures. Photopolymerization was effected by 0.2 wt% each of camphorquinone and N,N-dimethyl-p-toluidine. Specimen densities in dry and water saturated conditions were obtained by Archimedes' method. Water sorption and desorption were evaluated in a desorption-sorption-desorption cycle. Water uptake (%WU), water desorption (%WD), equilibrium solubility (ES; µg/mm3), swelling (f) and volume increase (%V) were calculated using appropriate equations. Results All resins with additives had increased %WU and ES. TEGDMA-containing systems presented higher %WU, %WD, ES, f and %V values, followed by resins based on CH3Bis-GMA and CF3Bis-GMA. Conclusions Aldehyde and diketone led to increases in the water sorption characteristics of experimental resins. PMID:23032211

  10. Sampling and Analysis for Lead in Water and Soil Samples on a University Campus: A Student Research Project.

    ERIC Educational Resources Information Center

    Butala, Steven J.; Zarrabi, Kaveh

    1995-01-01

    Describes a student research project that determined concentrations of lead in water drawn from selected drinking fountains and in selected soil samples on the campus of the University of Nevada, Las Vegas. (18 references) (DDR)

  11. Interstitial water studies on small core samples, Leg 15

    USGS Publications Warehouse

    Sayles, Fred L.; Manheim, Frank T.; Waterman, Lee S.

    1973-01-01

    Analyses of pore fluids from reducing environments demonstrate that reduction of SO4 is accompanied by large increases in alkalinity and strong depletion of Ca and Mg. The data are compatible with a model of replacement of Fe3+ in clay lattices by Mg from the interstitial solutions and the precipitation of pyrite. Depletions of Na in the interstitial solutions are related to Mg losses by a ratio of approximately 1:3. Pore fluids from oxidizing pelagic sediments exhibit little SO4 depletion. Losses of Mg are accompanied by the addition of Ca to the pore solutions on a nearly 1:1 basis. Strong Sr enrichment is also found in these solutions. The magnitude of the Sr increase suggests that considerable carbonate recrystallization has occurred. As part of an extensive interlaboratory and analytical calibration, the effect of squeezing sediment at different temperatures has been studied in depth. Samples of a variety of lithologies have been included. Enrichment of K by as much as 24 percent and depletion of Mg and Ca by up to 7 percent occurs during warming. However, no significant effect upon Cl and SO4 could be detected. The strongest effects are seen in the minor constituents studied. On warming, Sr, Si, and B are enriched as much as 19, 40, and 60 percent, respectively. The size of the observed concentration changes varies with the mineralogy of the sediment, but is significant in all types studied, particularly with regards to Mg and K.

  12. Recovery of several volatile organic compounds from simulated water samples: Effect of transport and storage

    USGS Publications Warehouse

    Friedman, L.C.; Schroder, L.J.; Brooks, M.G.

    1986-01-01

    Solutions containing volatile organic compounds were prepared in organic-free water and 2% methanol and submitted to two U.S. Geological Survey laboratories. Data from the determination of volatile compounds in these samples were compared to analytical data for the same volatile compounds that had been kept in solutions 100 times more concentrated until immediately before analysis; there was no statistically significant difference in the analytical recoveries. Addition of 2% methanol to the storage containers hindered the recovery of bromomethane and vinyl chloride. Methanol addition did not enhance sample stability. Further, there was no statistically significant difference in results from the two laboratories, and the recovery efficiency was more than 80% in more than half of the determinations made. In a subsequent study, six of eight volatile compounds showed no significant loss of recovery after 34 days.

  13. The development of catalytic nucleophilic additions of terminal alkynes in water.

    PubMed

    Li, Chao-Jun

    2010-04-20

    One of the major research endeavors in synthetic chemistry over the past two decades is the exploration of synthetic methods that work under ambient atmosphere with benign solvents, that maximize atom utilization, and that directly transform natural resources, such as renewable biomass, from their native states into useful chemical products, thus avoiding the need for protecting groups. The nucleophilic addition of terminal alkynes to various unsaturated electrophiles is a classical (textbook) reaction in organic chemistry, allowing the formation of a C-C bond while simultaneously introducing the alkyne functionality. A prerequisite of this classical reaction is the stoichiometric generation of highly reactive metal acetylides. Over the past decade, our laboratory and others have been exploring an alternative, the catalytic and direct nucleophilic addition of terminal alkynes to unsaturated electrophiles in water. We found that various terminal alkynes can react efficiently with a wide range of such electrophiles in water (or organic solvent) in the presence of simple and readily available catalysts, such as copper, silver, gold, iron, palladium, and others. In this Account, we describe the development of these synthetic methods, focusing primarily on results from our laboratory. Our studies include the following: (i) catalytic reaction of terminal alkynes with acid chloride, (ii) catalytic addition of terminal alkynes to aldehydes and ketones, (iii) catalytic addition of alkynes to C=N bonds, and (iv) catalytic conjugate additions. Most importantly, these reactions can tolerate various functional groups and, in many cases, perform better in water than in organic solvents, clearly defying classical reactivities predicated on the relative acidities of water, alcohols, and terminal alkynes. We further discuss multicomponent and enantioselective reactions that were developed. These methods provide an alternative to the traditional requirement of separate steps in

  14. Gasbuggy, New Mexico, Natural Gas and Produced Water Sampling and Analysis Results for 2011

    SciTech Connect

    2011-09-01

    The U.S. Department of Energy (DOE) Office of Legacy Management conducted natural gas sampling for the Gasbuggy, New Mexico, site on June 7 and 8, 2011. Natural gas sampling consists of collecting both gas samples and samples of produced water from gas production wells. Water samples from gas production wells were analyzed for gamma-emitting radionuclides, gross alpha, gross beta, and tritium. Natural gas samples were analyzed for tritium and carbon-14. ALS Laboratory Group in Fort Collins, Colorado, analyzed water samples. Isotech Laboratories in Champaign, Illinois, analyzed natural gas samples.

  15. Improvement in properties of coal water slurry by combined use of new additive and ultrasonic irradiation.

    PubMed

    Guo, Zhaobing; Feng, Ruo; Zheng, Youfei; Fu, Xiaoru

    2007-07-01

    Coal water slurry (CWS) was prepared with a newly developed additive from naphthalene oil. The effects of ultrasonic irradiation on coal particle size distribution (PSD), adsorption behavior of additive in coal particles and the characteristics of CWS were investigated. Results showed that ultrasonic irradiation led to a higher proportion of fine coal in CWS and increased the saturated adsorption amount of additive in coal particles. In addition, the rheological behavior and static stability of CWS irradiated by ultrasonic wave were remarkably improved. The changes on viscosity of CWS containing 1% and 2% additive are qualitatively different with the increasing sonication time studied. The reason for the different effect of sonication time on CWS viscosity is presented in this study.

  16. New water-soluble metal working fluids additives from phosphonic acid derivatives for aluminum alloy materials.

    PubMed

    Kohara, Ichitaro; Tomoda, Hideyuki; Watanabe, Shoji

    2007-01-01

    Water-soluble metal working fluids are used for processing of aluminum alloy materials. This short paper describes properties of new additives for water-soluble cutting fluids for aluminum alloy materials. Some alkyldiphosphonic acids were prepared with known method. Amine salts of these phosphonic acids showed anti-corrosion property for aluminum alloy materials. However, they have no hard water tolerance. Monoesters of octylphosphonic acid were prepared by the reaction of octylphosphonic acid dichloride with various alcohols in the presence of triethylamine. Amine salts of monoester of octylphosphonic acid with diethyleneglycol monomethyl ether, ethyleneglycol monomethyl ether and triethyleneglycol monomethyl ether showed both of a good anti-corrosion property for aluminum alloy materials and hard water tolerance.

  17. [Identification of Systemic Contaminations with Legionella Spec. in Drinking Water Plumbing Systems: Sampling Strategies and Corresponding Parameters].

    PubMed

    Völker, S; Schreiber, C; Müller, H; Zacharias, N; Kistemann, T

    2015-11-30

    After the amendment of the Drinking Water Ordinance in 2011, the requirements for the hygienic-microbiological monitoring of drinking water installations have increased significantly. In the BMBF-funded project "Biofilm Management" (2010-2014), we examined the extent to which established sampling strategies in practice can uncover drinking water plumbing systems systemically colonized with Legionella. Moreover, we investigated additional parameters that might be suitable for detecting systemic contaminations. We subjected the drinking water plumbing systems of 8 buildings with known microbial contamination (Legionella) to an intensive hygienic-microbiological sampling with high spatial and temporal resolution. A total of 626 drinking hot water samples were analyzed with classical culture-based methods. In addition, comprehensive hygienic observations were conducted in each building and qualitative interviews with operators and users were applied. Collected tap-specific parameters were quantitatively analyzed by means of sensitivity and accuracy calculations. The systemic presence of Legionella in drinking water plumbing systems has a high spatial and temporal variability. Established sampling strategies were only partially suitable to detect long-term Legionella contaminations in practice. In particular, the sampling of hot water at the calorifier and circulation re-entrance showed little significance in terms of contamination events. To detect the systemic presence of Legionella,the parameters stagnation (qualitatively assessed) and temperature (compliance with the 5K-rule) showed better results.

  18. Data Validation Package April 2016 Groundwater and Surface Water Sampling at the Monticello, Utah, Disposal and Processing Sites August 2016

    SciTech Connect

    Nguyen, Jason; Smith, Fred

    2016-08-01

    This semiannual event includes sampling groundwater and surface water at the Monticello Disposal and Processing Sites. Sampling and analyses were conducted as specified in the Sampling and Analysis Plan for U.S. Department of Energy Office of Legacy Management Sites (LMS/PRO/S04351, continually updated) and Program Directive MNT-2016-01. Complete sample sets were collected from 42 of 48 planned locations (9 of 9 former mill site wells, 13 of 13 downgradient wells, 7 of 9 downgradient permeable reactive barrier wells, 4 of 7 seeps and wetlands, and 9 of 10 surface water locations). Planned monitoring locations are shown in Attachment 1, Sampling and Analysis Work Order. Locations R6-M3, SW00-01, Seep 1, Seep 2, and Seep 5 were not sampled due to insufficient water availability. A partial sample was collected at location R4-M3 due to insufficient water. All samples from the permeable reactive barrier wells were filtered as specified in the program directive. Duplicate samples were collected from surface water location Sorenson and from monitoring wells 92-07 and RlO-Ml. Water levels were measured at all sampled wells and an additional set of wells. See Attachment2, Trip Report for additional details. The contaminants of concern (COCs) for the Monticello sites are arsenic, manganese, molybdenum, nitrate+ nitrite as nitrogen (nitrate+ nitrite as N), selenium, uranium, and vanadium. Locations with COCs that exceeded remediation goals are listed in Table 1 and Table 2. Time-concentration graphs of the COCs for all groundwater and surface water locations are included in Attachment 3, Data Presentation. An assessment of anomalous data is included in Attachment 4.

  19. TRITIUM UNCERTAINTY ANALYSIS FOR SURFACE WATER SAMPLES AT THE SAVANNAH RIVER SITE

    SciTech Connect

    Atkinson, R.

    2012-07-31

    Radiochemical analyses of surface water samples, in the framework of Environmental Monitoring, have associated uncertainties for the radioisotopic results reported. These uncertainty analyses pertain to the tritium results from surface water samples collected at five locations on the Savannah River near the U.S. Department of Energy's Savannah River Site (SRS). Uncertainties can result from the field-sampling routine, can be incurred during transport due to the physical properties of the sample, from equipment limitations, and from the measurement instrumentation used. The uncertainty reported by the SRS in their Annual Site Environmental Report currently considers only the counting uncertainty in the measurements, which is the standard reporting protocol for radioanalytical chemistry results. The focus of this work is to provide an overview of all uncertainty components associated with SRS tritium measurements, estimate the total uncertainty according to ISO 17025, and to propose additional experiments to verify some of the estimated uncertainties. The main uncertainty components discovered and investigated in this paper are tritium absorption or desorption in the sample container, HTO/H{sub 2}O isotopic effect during distillation, pipette volume, and tritium standard uncertainty. The goal is to quantify these uncertainties and to establish a combined uncertainty in order to increase the scientific depth of the SRS Annual Site Environmental Report.

  20. Evaluation of the toxicological properties of ground- and surface-water samples from the Aral Sea Basin.

    PubMed

    Bosch, K; Erdinger, L; Ingel, F; Khussainova, S; Utegenova, E; Bresgen, N; Eckl, P M

    2007-03-01

    In order to determine whether there is a potential health risk associated with the water supply in the Aral Sea Basin, ground- and surface-water samples were collected in and around Aralsk and from the Aral Sea in 2002. Water samples from Akchi, a small town close to Almaty, served as controls. Bioassays with different toxicological endpoints were employed to assess the general toxicological status. Additionally, the samples were analysed for microbial contamination. The samples were tested in the primary hepatocyte assay for their potential to induce micronuclei and chromosomal aberrations as cumulative indicators for genotoxicity. In parallel, the effects on cell proliferation evidenced by mitotic index and cytotoxicity such as the appearance of necrotic and apoptotic cells, were determined. Furthermore, samples were examined using the Microtox assay for general toxicity. Chemical analysis according to European regulations was performed and soil and water samples were analysed for DDT and DDE. The results obtained indicated no increased cyto- or genotoxic potential of the water samples, nor levels of DDT or DDE exceeding the thresholds levels suggested by WHO. Our data therefore do not support the hypothesis that the contamination of the drinking water in and around Aralsk is responsible for the health effects previously described such as increased rates of liver disease and in particular liver cancer. Microbiological analysis, however, revealed the presence of contamination in most samples analysed.

  1. The Use of Additional GPS Frequencies to Independently Determine Tropospheric Water Vapor Profiles

    NASA Technical Reports Server (NTRS)

    Herman, B.M.; Feng, D.; Flittner, D. E.; Kursinski, E. R.

    2000-01-01

    It is well known that the currently employed L1 and L2 GPS/MET frequencies (1.2 - 1.6) Ghz) do not allow for the separation of water vapor and density (or temperature) from active microwave occultation measurements in regions of the troposphere warmer than 240 K Therefore, additional information must be used, from other types of measurements and weather analyses, to recover water vapor (and temperature) profiles. Thus in data sparse regions, these inferred profiles can be subject to larger errors than would result in data rich regions. The use of properly selected additional GPS frequencies enables a direct, independent measurement of the absorption associated with the water vapor profile, which may then be used in the standard GPS/MET retrievals to obtain a more accurate determination of atmospheric temperature throughout the water vapor layer. This study looks at the use of microwave crosslinks in the region of the 22 Ghz water vapor absorption line for this purpose. An added advantage of using 22 Ghz frequencies is that they are only negligibly affected by the ionosphere in contrast to the large effect at the GPS frequencies. The retrieval algorithm uses both amplitude and phase measurements to obtain profiles of atmospheric pressure, temperature and water water vapor pressure with a vertical resolution of 1 km or better. This technique also provides the cloud liquid water content along the ray path, which is in itself an important element in climate monitoring. Advantages of this method include the ability to make measurements in the presence of clouds and the use of techniques and technology proven through the GPS/MET experiment and several of NASA's planetary exploration missions. Simulations demonstrating this method will be presented for both clear and cloudy sky conditions.

  2. Escherichia coli in marine water: Comparison of methods for the assessment of recreational bathing water samples.

    PubMed

    Lušić, Darija Vukić; Jozić, Slaven; Cenov, Arijana; Glad, Marin; Bulić, Marko; Lušić, Dražen

    2016-12-15

    Bathing Water Directive (2006/7/EC) specifies two reference methods for Escherichia coli detection: ISO 9308-1 and 9308-3. The revised ISO 9308-1 is recommended only for waters with a low bacterial background flora. Considering the extended time needed for analysis and, generally, the lack of experience in using ISO 9308-3 in the Mediterranean, the suitability of ISO 9308-1 for the examination of E. coli in bathing water was evaluated. The present study was aimed at a comparison of data obtained by the reference method in seawater samples (110 beaches, N=477) with data received from six alternative methods. Results show that recently used TSA/TBA method may overestimate E. coli numbers in marine waters. The temperature modified ISO 9308-1 (44°C) did not significantly alter the results, but outperformed the antibiotic supplemented agar at reducing non-E. coli bacteria on the plates, allowing the use of the respective method for monitoring coastal water.

  3. Ballast water sampling as a critical component of biological invasions risk management.

    PubMed

    David, Matej; Perkovic, Marko

    2004-08-01

    The human mediated transfer of harmful organisms via shipping, specifically via ballast water transport, leading to the loss of biodiversity, alteration of ecosystems, negative impacts on human health and in some regions economic loss, has raised considerable attention especially in the last decade. Ballast water sampling is very important for biological invasions risk management. The complexity of ballast water sampling is a result of both the variety of organism diversity and behaviour, as well as ship design including availability of ballast water sampling points. Furthermore, ballast water sampling methodology is influenced by the objectives of the sampling study. In the course of research conducted in Slovenia, new sampling equipment for ships' ballast water was developed and tested. In this paper new ballast water sampling methods and equipment together with practical shipboard testing results are presented.

  4. Sample data processing in an additive and reproducible taxonomic workflow by using character data persistently linked to preserved individual specimens

    PubMed Central

    Kilian, Norbert; Henning, Tilo; Plitzner, Patrick; Müller, Andreas; Güntsch, Anton; Stöver, Ben C.; Müller, Kai F.; Berendsohn, Walter G.; Borsch, Thomas

    2015-01-01

    We present the model and implementation of a workflow that blazes a trail in systematic biology for the re-usability of character data (data on any kind of characters of pheno- and genotypes of organisms) and their additivity from specimen to taxon level. We take into account that any taxon characterization is based on a limited set of sampled individuals and characters, and that consequently any new individual and any new character may affect the recognition of biological entities and/or the subsequent delimitation and characterization of a taxon. Taxon concepts thus frequently change during the knowledge generation process in systematic biology. Structured character data are therefore not only needed for the knowledge generation process but also for easily adapting characterizations of taxa. We aim to facilitate the construction and reproducibility of taxon characterizations from structured character data of changing sample sets by establishing a stable and unambiguous association between each sampled individual and the data processed from it. Our workflow implementation uses the European Distributed Institute of Taxonomy Platform, a comprehensive taxonomic data management and publication environment to: (i) establish a reproducible connection between sampled individuals and all samples derived from them; (ii) stably link sample-based character data with the metadata of the respective samples; (iii) record and store structured specimen-based character data in formats allowing data exchange; (iv) reversibly assign sample metadata and character datasets to taxa in an editable classification and display them and (v) organize data exchange via standard exchange formats and enable the link between the character datasets and samples in research collections, ensuring high visibility and instant re-usability of the data. The workflow implemented will contribute to organizing the interface between phylogenetic analysis and revisionary taxonomic or monographic work

  5. The effect of sampling strategies on assessment of water quality criteria attainment.

    PubMed

    Wang, Yuxin; Wilson, Jessica M; VanBriesen, Jeanne M

    2015-05-01

    Sample locations for large river studies affect the representativeness of data, and thus can alter decisions made regarding river conditions and the need for interventions to improve water quality. The present study evaluated three water-quality sampling programs for Total Dissolved Solid (TDS) assessment in the Monongahela River from 2008 to 2012. The sampling plans cover the same 145 km of river but differ in frequency, sample location and type (e.g., river water sample vs drinking water plant intake sample). Differences resulting from temporal and spatial variability in sampling lead to different conclusions regarding water quality in the river (including regulatory listing decisions), especially when low flow leads to concentrations at or near the water quality criteria (500mg/L TDS). Drinking water samples exceeded the criteria 82 out of 650 samples (12.6%), while river water samples exceeded the criteria 47 out of 464 samples (10.1%). Different water sample types could provide different pictures of water quality in the river and lead to different regulatory listing decisions.

  6. Stable isotope analysis of saline water samples on a cavity ring-down spectroscopy instrument.

    PubMed

    Skrzypek, Grzegorz; Ford, Douglas

    2014-01-01

    The analysis of the stable hydrogen and oxygen isotope composition of water using cavity ring-down spectroscopy (CRDS) instruments utilizing infrared absorption spectroscopy have been comprehensively tested. However, potential limitations of infrared spectroscopy for the analysis of highly saline water have not yet been evaluated. In this study, we assessed uncertainty arising from elevated salt concentrations in water analyzed on a CRDS instrument and the necessity of a correction procedure. We prepared various solutions of mixed salts and separate solutions with individual salts (NaCl, KCl, MgCl2, and CaCl2) using deionized water with a known stable isotope composition. Most of the individual salt and salt mixture solutions (some up to 340 g L(-1)) had δ-values within the range usual for CRDS analytical uncertainty (0.1‰ for δ (18)O and 1.0‰ for δ (2)H). Results were not compromised even when the total load of salt in the vaporizer reached ∼38.5 mg (equivalent to build up after running ∼100 ocean water samples). Therefore, highly saline mixtures can be successfully analyzed using CRDS, except highly concentrated MgCl2 solutions, without the need for an additional correction if the vaporizer is frequently cleaned and MgCl2 concentration in water is relatively low.

  7. Preparation and assessment of a candidate reference sample of Lake Baikal deep water

    NASA Astrophysics Data System (ADS)

    Suturin, A. N.; Paradina, L. F.; Epov, V. N.; Semenov, A. R.; Lozhkin, V. I.; Petrov, L. L.

    2003-02-01

    The possibility of the creation of a multi-element reference sample of Lake Baikal deep-water composition is justified. This is a new type of reference sample composed of natural water with a wide range of macro- and microelements. This candidate reference sample has a matrix composition consisting of hydrocarbonate and calcium water, a composition that is typical of many rivers and lakes of the world, as well as rain water. The creation of a candidate reference sample of Lake Baikal water is possible due to the stable water composition at a depth of 500 m, and to the use of water sampling technology which results in the preservation of the initial composition of water and its absolute sterility. Trial batches of Baikal water collected annually and stored in special polyethylenetereftalate bottles for a period of 9 years remained stable and homogenous for most elements. Preliminary data for a range of elements and compounds are presented.

  8. Measurement of Mercury Methylation in Lake Water and Sediment Samples

    PubMed Central

    Furutani, Akira; Rudd, John W. M.

    1980-01-01

    Biological mercury methylation was assayed by a new radiochemical technique in the water column and sediments of a mercury-contaminated lake. In 24 weeks during 1979, there were three episodes of methylating activity in surface floc and in water, each lasting 3 to 5 weeks. Periods of methylation in the water column coincided with surface sediment methylation and appeared to be related to overall microbial activity. Mercury was actively methylated in the presence of bound sulfide. PMID:16345649

  9. Graphene-coated fiber for solid-phase microextraction of triazine herbicides in water samples.

    PubMed

    Wu, Qiuhua; Feng, Cheng; Zhao, Guangying; Wang, Chun; Wang, Zhi

    2012-01-01

    Graphene is a novel and interesting carbon material that could be used for the separation and purification of some chemical compounds. In this investigation, graphene was used as a novel fiber-coating material for the solid-phase microextraction (SPME) of four triazine herbicides (atrazine, prometon, ametryn and prometryn) in water samples. The main parameters that affect the extraction and desorption efficiencies, such as the extraction time, stirring rate, salt addition, desorption solvent and desorption time, were investigated and optimized. The optimized SPME by graphene-coated fiber coupled with high-performance liquid chromatography-diode array detection (HPLC-DAD) was successfully applied for the determination of the four triazine herbicides in water samples. The linearity of the method was in the range from 0.5 to 200 ng/mL, with the correlation coefficients (r) ranging from 0.9989 to 0.9998. The limits of detection of the method were 0.05-0.2 ng/mL. The relative standard deviations varied from 3.5 to 4.9% (n=5). The recoveries of the triazine herbicides from water samples at spiking levels of 20.0 and 50.0  ng/mL were in the range between 86.0 and 94.6%. Compared with two commercial fibers (CW/TPR, 50 μm; PDMS/DVB, 60 μm), the graphene-coated fiber showed higher extraction efficiency.

  10. Water adsorption at high temperature on core samples from The Geysers geothermal field

    SciTech Connect

    Gruszkiewicz, M.S.; Horita, J.; Simonson, J.M.; Mesmer, R.E.

    1998-06-01

    The quantity of water retained by rock samples taken from three wells located in The Geysers geothermal field, California, was measured at 150, 200, and 250 C as a function of steam pressure in the range 0.00 {le} p/p{sub 0} {le} 0.98, where p{sub 0} is the saturated water vapor pressure. Both adsorption and desorption runs were made in order to investigate the extent of the hysteresis. Additionally, low temperature gas adsorption analyses were made on the same rock samples. Mercury intrusion porosimetry was also used to obtain similar information extending to very large pores (macropores). A qualitative correlation was found between the surface properties obtained from nitrogen adsorption and the mineralogical and petrological characteristics of the solids. However, there was no direct correlation between BET specific surface areas and the capacity of the rocks for water adsorption at high temperatures. The hysteresis decreased significantly at 250 C. The results indicate that multilayer adsorption, rather than capillary condensation, is the dominant water storage mechanism at high temperatures.

  11. Water adsorption at high temperature on core samples from The Geysers geothermal field

    SciTech Connect

    Gruszkiewicz, M.S.; Horita, J.; Simonson, J.M.; Mesmer, R.E.

    1998-06-01

    The quantity of water retained by rock samples taken from three wells located in The Geysers geothermal reservoir, California, was measured at 150, 200, and 250 C as a function of pressure in the range 0.00 {le} p/p{sub 0} {le} 0.98, where p{sub 0} is the saturated water vapor pressure. Both adsorption (increasing pressure) and desorption (decreasing pressure) runs were made in order to investigate the nature and the extent of the hysteresis. Additionally, low temperature gas adsorption analyses were performed on the same rock samples. Nitrogen or krypton adsorption and desorption isotherms at 77 K were used to obtain BET specific surface areas, pore volumes and their distributions with respect to pore sizes. Mercury intrusion porosimetry was also used to obtain similar information extending to very large pores (macropores). A qualitative correlation was found between the surface properties obtained from nitrogen adsorption and the mineralogical and petrological characteristics of the solids. However, there is in general no proportionality between BET specific surface areas and the capacity of the rocks for water adsorption at high temperatures. The results indicate that multilayer adsorption rather than capillary condensation is the dominant water storage mechanism at high temperatures.

  12. Improving the solid-phase extraction of "quat" pesticides from water samples. Removal of interferences.

    PubMed

    Ibáñez, M; Picó, Y; Mañes, J

    1998-10-09

    A novel strategy, based on the addition of a cationic surfactant, for preventing the interferences associated with a diminution in the efficacy of solid-phase extraction (SPE) with silica cartridges of diquat, paraquat and difenzoquat in water is developed. Conditions for extraction are optimised with respect to pH, cationic surfactant and its concentration. Humic acids, anionic surfactants, inorganic salts and other organic contaminants like pesticides, phenols, polycyclic aromatic hydrocarbons and polychlorinated biphenyls produce the studied interferences. The best performance is shown in the improvement of the "quats" recovery from waters with high levels of humic acids and anionic surfactants (recovery is increased from ca. 30% to more than 80%). Unfortunately, the strong interference from inorganic salts remains. The presence in the water sample of other organic contaminants only affected the extraction efficiency of difenzoquat at high concentrations (more than 1 mg/l). Analytic utility is illustrated by selective measurements of the three herbicides, in real water samples. Overall, the results show that in spite of its drawbacks, SPE is a useful technique that allows the detection and quantification of the "quats" at limits below 100 ng/l as established by the European Union.

  13. LABORATORY ANALYSIS FOR ARSENIC IN DRINKING WATER SAMPLES

    EPA Science Inventory

    The U.S. Environmental Protection Agency (USEPA) has established maximum contaminant levels ( MCLs ), for many inorganic contaminants found in drinking water, to protect the health of consumers. Some of these chemicals occur naturally in source waters while some are the result o...

  14. Precision of a splitting device for water samples

    USGS Publications Warehouse

    Capel, Paul D.; Nacionales, Fernando C.; Larson, Steven J.

    1995-01-01

    Two identical cone splitters, devices designed to split water and its suspended solids into equal aliquots for semi-volatile organic chemical and trace element analyses, were evaluated for their precision. The water-splitting evaluations consisted of experiments to test the effect of water volume, the effect of combining outlet ports, and the effect of different techniques of water introduction. The solids-splitting evaluations consisted of experi- ments to test the effect of particle size (nine different particle diameters ranging from very coarse sand to clay) and suspended-solids concentration. In general, water was equally split with a precision of less than 5 percent relative standard deviation. The accuracy of splitting the solids was a function of particle size. Clay, silt, and fine and medium sand were split with a precision relative standard deviation of less than 7 percent, and coarse sand was split with a relative standard deviation between 12 and 45 percent.

  15. Acidification of East Siberian Arctic Shelf waters through addition of freshwater and terrestrial carbon

    NASA Astrophysics Data System (ADS)

    Semiletov, Igor; Pipko, Irina; Gustafsson, Örjan; Anderson, Leif G.; Sergienko, Valentin; Pugach, Svetlana; Dudarev, Oleg; Charkin, Alexander; Gukov, Alexander; Bröder, Lisa; Andersson, August; Spivak, Eduard; Shakhova, Natalia

    2016-05-01

    Ocean acidification affects marine ecosystems and carbon cycling, and is considered a direct effect of anthropogenic carbon dioxide uptake from the atmosphere. Accumulation of atmospheric CO2 in ocean surface waters is predicted to make the ocean twice as acidic by the end of this century. The Arctic Ocean is particularly sensitive to ocean acidification because more CO2 can dissolve in cold water. Here we present observations of the chemical and physical characteristics of East Siberian Arctic Shelf waters from 1999, 2000-2005, 2008 and 2011, and find extreme aragonite undersaturation that reflects acidity levels in excess of those projected in this region for 2100. Dissolved inorganic carbon isotopic data and Markov chain Monte Carlo simulations of water sources using salinity and δ18O data suggest that the persistent acidification is driven by the degradation of terrestrial organic matter and discharge of Arctic river water with elevated CO2 concentrations, rather than by uptake of atmospheric CO2. We suggest that East Siberian Arctic Shelf waters may become more acidic if thawing permafrost leads to enhanced terrestrial organic carbon inputs and if freshwater additions continue to increase, which may affect their efficiency as a source of CO2.

  16. Vaporization Mechanisms of Water-Insoluble Cs in Ash During Thermal Treatment with Calcium Chloride Addition.

    PubMed

    Jiao, Facun; Iwata, Norie; Kinoshita, Norikazu; Kawaguchi, Masato; Asada, Motoyuki; Honda, Maki; Sueki, Keisuke; Ninomiya, Yoshihiko

    2016-12-20

    The vaporization mechanisms of water-insoluble Cs in raw ash and Cs-doped ash during thermal treatment with CaCl2 addition was systematically examined in a lab-scale electrical heating furnace over a temperature range of 500-1500 °C. The results indicate that the water-insoluble Cs in the ash was associated with aluminosilicate as pollucite. Addition of 10% CaCl2 caused the maximum vaporization ratio of Cs in the raw ash to reach approximately 80% at temperatures higher than 1200 °C, whereas approximately 95% of Cs was vaporized at temperatures higher than 1300 °C when 30% CaCl2 was added. The formation of an intermediate compound, CsCaCl3, through the chemical reaction of Cs with CaCl2 was responsible for Cs vaporization by means of the subsequent decomposition of this intermediate upon the increase in temperature. The indirect chlorination of Cs by the gaseous chlorine released from the decomposition of CaCl2 was insignificant. A high CaCl2 content in the resulting annealed products with 30% CaCl2 addition delayed the decomposition of CsCaCl3 and thus lowered the Cs vaporization ratio compared to that with 10% CaCl2 addition at 900-1250 °C. Thermal treatment with CaCl2 addition is a proposed method to remove Cs from Cs-contaminated incineration ash.

  17. Standard addition method for the determination of pharmaceutical residues in drinking water by SPE-LC-MS/MS.

    PubMed

    Cimetiere, Nicolas; Soutrel, Isabelle; Lemasle, Marguerite; Laplanche, Alain; Crocq, André

    2013-01-01

    The study of the occurrence and fate of pharmaceutical compounds in drinking or waste water processes has become very popular in recent years. Liquid chromatography with tandem mass spectrometry is a powerful analytical tool often used to determine pharmaceutical residues at trace level in water. However, many steps may disrupt the analytical procedure and bias the results. A list of 27 environmentally relevant molecules, including various therapeutic classes and (cardiovascular, veterinary and human antibiotics, neuroleptics, non-steroidal anti-inflammatory drugs, hormones and other miscellaneous pharmaceutical compounds), was selected. In this work, a method was developed using ultra performance liquid chromatography coupled to tandem mass spectrometry (UPLC-MS/MS) and solid-phase extraction to determine the concentration of the 27 targeted pharmaceutical compounds at the nanogram per litre level. The matrix effect was evaluated from water sampled at different treatment stages. Conventional methods with external calibration and internal standard correction were compared with the standard addition method (SAM). An accurate determination of pharmaceutical compounds in drinking water was obtained by the SAM associated with UPLC-MS/MS. The developed method was used to evaluate the occurrence and fate of pharmaceutical compounds in some drinking water treatment plants in the west of France.

  18. Trace level determination of u, zn, cd, pb and cu in drinking water samples.

    PubMed

    Kumar, Mukesh; Singh, Surinder; Mahajan, Rakesh Kumar

    2006-01-01

    The concentration of uranium has been assessed in drinking water samples collected from different locations in Bathinda district, Punjab, India. The water samples are taken from hand pumps and tube wells. Uranium is determined using fission track technique. Uranium concentration in the water samples varies from 2.23+/- 0.05 to 87.05+/- 0.29 microg/L. These values are compared with safe limit values recommended for drinking water. The uranium concentration in almost all drinking water samples is found to be more than the safe limit. Analysis of some heavy metals viz. Zn, Cd, Pb and Cu in water is made. The concentration of sodium, potassium, calcium, magnesium, chlorine and total hardness along with the pH value and conductivity of the water samples are measured. Some of the samples show stunningly high values of these parameters.

  19. Detection of triazole deicing additives in soil samples from airports with low, mid, and large volume aircraft deicing activities.

    PubMed

    McNeill, K S; Cancilla, D A

    2009-03-01

    Soil samples from three USA airports representing low, mid, and large volume users of aircraft deicing fluids (ADAFs) were analyzed by LC/MS/MS for the presence of triazoles, a class of corrosion inhibitors historically used in ADAFs. Triazoles, specifically the 4-methyl-1H-benzotriazole and the 5-methyl-1H-benzotriazole, were detected in a majority of samples and ranged from 2.35 to 424.19 microg/kg. Previous studies have focused primarily on ground and surface water impacts of larger volume ADAF users. The detection of triazoles in soils at low volume ADAF use airports suggests that deicing activities may have a broader environmental impact than previously considered.

  20. Effect of addition of water-soluble chitin on amylose film.

    PubMed

    Suzuki, Shiho; Shimahashi, Katsumasa; Takahara, Junichi; Sunako, Michihiro; Takaha, Takeshi; Ogawa, Kozo; Kitamura, Shinichi

    2005-01-01

    Amylose films blended with chitosan, which were free from additives such as acid, salt, and plasticizer, were prepared by casting mixtures of an aqueous solution of an enzymatically synthesized amylose and that of water-soluble chitin (44.1% deacetylated). The presence of a small amount of chitin (less than 10%) increased significantly the permeability of gases (N2, O2, CO2, C2H4) and improved the mechanical parameters of amylose film; particularly, the elastic modulus and elongation of the blend films were larger than those of amylose or chitin films. No antibacterial activity was observed with either amylose or water-soluble chitin films. But amylose films having a small amount of chitin showed strong antibacterial action, suggesting a morphological change in water-soluble chitin on the film surface by blending with amylose molecule. These facts suggested the presence of a molecular complex of amylose and chitosan.

  1. Produced water chemistry data for samples from four petroleum wells, Southern San Joaquin Valley, California, 2014

    USGS Publications Warehouse

    Davis, Tracy A.; Kulongoski, Justin; McMahon, Peter B.

    2016-01-01

    The U.S. Geological Survey (USGS) in cooperation with the California State Water Resources Control Board collected produced water samples from four petroleum wells in the southern San Joaquin Valley on November 5, 2014. This digital dataset contains the site information, analyzing laboratories and methods, and water chemistry and quality control results for these samples. Water chemistry results include concentrations of dissolved hydrocarbon gases and their isotopic composition; concentrations of inorganic constituents including salinity, major ions, and nutrients; dissolved organic carbon; and stable isotopes of water and strontium dissolved in water. Samples were analyzed by 5 laboratories operated or contracted by the USGS.

  2. 40 CFR 258.53 - Ground-water sampling and analysis requirements.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ....53 Ground-water sampling and analysis requirements. (a) The ground-water monitoring program must... 40 Protection of Environment 24 2010-07-01 2010-07-01 false Ground-water sampling and analysis requirements. 258.53 Section 258.53 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED)...

  3. The methods of receiving coal water suspension and its use as the modifying additive in concrete

    NASA Astrophysics Data System (ADS)

    Buyantuyev, S. L.; Urkhanova, L. A.; Lkhasaranov, S. A.; Stebenkova, Y. Y.; Khmelev, A. B.; Kondratenko, A. S.

    2017-01-01

    Results of research of the coal water suspension (CWS) from a cake received in the electrodigit ways in the fluid environment and gas are given in article and also the possibilities of its use as the modifying additive in concrete are considered. Use of a coal cake is perspective as it is a withdrawal of the coal and concentrating enterprises and has extremely low cost. Methods of receiving CWS and possibility of formation of carbon nanomaterials (CNM) are given in their structure. Research and the analysis of a microstructure of a surface of exemplars before electrodigit processing, their element structure, dependence of durability of a cement stone on a look and quantity of an additive of CWS is conducted. For modification of cement the carbon nanomaterials received from the following exemplars of water coal suspensions were used: foams from a cake from a scrubber of the plasma modular reactor, coal water suspension from a cake from electrodigit installation. The product which can find further application for a power engineering as fuel for combustion, and also in structural materials science, in particular, as the modifying additive in concrete allows to receive these methods.

  4. Rapid Recovery of Cyanobacterial Pigments in Desiccated Biological Soil Crusts following Addition of Water

    PubMed Central

    Abed, Raeid M. M.; Polerecky, Lubos; Al-Habsi, Amal; Oetjen, Janina; Strous, Marc; de Beer, Dirk

    2014-01-01

    We examined soil surface colour change to green and hydrotaxis following addition of water to biological soil crusts using pigment extraction, hyperspectral imaging, microsensors and 13C labeling experiments coupled to matrix-assisted laser desorption and ionization time of flight-mass spectrometry (MALD-TOF MS). The topsoil colour turned green in less than 5 minutes following water addition. The concentrations of chlorophyll a (Chl a), scytonemin and echinenon rapidly increased in the top <1 mm layer while in the deeper layer, their concentrations remained low. Hyperspectral imaging showed that, in both wet and dehydrated crusts, cyanobacteria formed a layer at a depth of 0.2–0.4 mm and this layer did not move upward after wetting. 13C labeling experiments and MALDI TOF analysis showed that Chl a was already present in the desiccated crusts and de novo synthesis of this molecule started only after 2 days of wetting due to growth of cyanobacteria. Microsensor measurements showed that photosynthetic activity increased concomitantly with the increase of Chl a, and reached a maximum net rate of 92 µmol m−2 h−1 approximately 2 hours after wetting. We conclude that the colour change of soil crusts to green upon water addition was not due to hydrotaxis but rather to the quick recovery and reassembly of pigments. Cyanobacteria in crusts can maintain their photosynthetic apparatus intact even under prolonged periods of desiccation with the ability to resume their photosynthetic activities within minutes after wetting. PMID:25375172

  5. Rapid recovery of cyanobacterial pigments in desiccated biological soil crusts following addition of water.

    PubMed

    Abed, Raeid M M; Polerecky, Lubos; Al-Habsi, Amal; Oetjen, Janina; Strous, Marc; de Beer, Dirk

    2014-01-01

    We examined soil surface colour change to green and hydrotaxis following addition of water to biological soil crusts using pigment extraction, hyperspectral imaging, microsensors and 13C labeling experiments coupled to matrix-assisted laser desorption and ionization time of flight-mass spectrometry (MALD-TOF MS). The topsoil colour turned green in less than 5 minutes following water addition. The concentrations of chlorophyll a (Chl a), scytonemin and echinenon rapidly increased in the top <1 mm layer while in the deeper layer, their concentrations remained low. Hyperspectral imaging showed that, in both wet and dehydrated crusts, cyanobacteria formed a layer at a depth of 0.2-0.4 mm and this layer did not move upward after wetting. 13C labeling experiments and MALDI TOF analysis showed that Chl a was already present in the desiccated crusts and de novo synthesis of this molecule started only after 2 days of wetting due to growth of cyanobacteria. Microsensor measurements showed that photosynthetic activity increased concomitantly with the increase of Chl a, and reached a maximum net rate of 92 µmol m-2 h-1 approximately 2 hours after wetting. We conclude that the colour change of soil crusts to green upon water addition was not due to hydrotaxis but rather to the quick recovery and reassembly of pigments. Cyanobacteria in crusts can maintain their photosynthetic apparatus intact even under prolonged periods of desiccation with the ability to resume their photosynthetic activities within minutes after wetting.

  6. Hydrogen production from water decomposition by redox of Fe 2O 3 modified with single- or double-metal additives

    NASA Astrophysics Data System (ADS)

    Liu, Xiaojie; Wang, Hui

    2010-05-01

    Iron oxide modified with single- or double-metal additives (Cr, Ni, Zr, Ag, Mo, Mo-Cr, Mo-Ni, Mo-Zr and Mo-Ag), which can store and supply pure hydrogen by reduction of iron oxide with hydrogen and subsequent oxidation of reduced iron oxide with steam (Fe 3O 4 (initial Fe 2O 3)+4H 2↔3Fe+4H 2O), were prepared by impregnation. Effects of various metal additives in the samples on hydrogen production were investigated by the above-repeated redox. All the samples with Mo additive exhibited a better redox performance than those without Mo, and the Mo-Zr additive in iron oxide was the best effective one enhancing hydrogen production from water decomposition. For Fe 2O 3-Mo-Zr, the average H 2 production temperature could be significantly decreased to 276 °C, the average H 2 formation rate could be increased to 360.9-461.1 μmol min -1 Fe-g -1 at operating temperature of 300 °C and the average storage capacity was up to 4.73 wt% in four cycles, an amount close to the IEA target.

  7. Transgenic nematodes as biosensors for metal stress in soil pore water samples.

    PubMed

    Anbalagan, Charumathi; Lafayette, Ivan; Antoniou-Kourounioti, Melissa; Haque, Mainul; King, John; Johnsen, Bob; Baillie, David; Gutierrez, Carmen; Martin, Jose A Rodriguez; de Pomerai, David

    2012-03-01

    Caenorhabditis elegans strains carrying stress-reporter green fluorescent protein transgenes were used to explore patterns of response to metals. Multiple stress pathways were induced at high doses by most metals tested, including members of the heat shock, oxidative stress, metallothionein (mtl) and xenobiotic response gene families. A mathematical model (to be published separately) of the gene regulatory circuit controlling mtl production predicted that chemically similar divalent metals (classic inducers) should show additive effects on mtl gene induction, whereas chemically dissimilar metals should show interference. These predictions were verified experimentally; thus cadmium and mercury showed additive effects, whereas ferric iron (a weak inducer) significantly reduced the effect of mercury. We applied a similar battery of tests to diluted samples of soil pore water extracted centrifugally after mixing 20% w/w ultrapure water with air-dried soil from an abandoned lead/zinc mine in the Murcia region of Spain. In addition, metal contents of both soil and soil pore water were determined by ICP-MS, and simplified mixtures of soluble metal salts were tested at equivalent final concentrations. The effects of extracted soil pore water (after tenfold dilution) were closely mimicked by mixtures of its principal component ions, and even by the single most prevalent contaminant (zinc) alone, though other metals modulated its effects both positively and negatively. In general, mixtures containing similar (divalent) metal ions exhibited mainly additive effects, whereas admixture of dissimilar (e.g. trivalent) ions often resulted in interference, reducing overall levels of stress-gene induction. These findings were also consistent with model predictions.

  8. Pushpoint sampling for defining spatial and temporal variations in contaminant concentrations in sediment pore water near the ground-water / surface-water interface

    USGS Publications Warehouse

    Zimmerman, Marc J.; Massey, Andrew J.; Campo, Kimberly W.

    2005-01-01

    During four periods from April 2002 to June 2003, pore-water samples were taken from river sediment within a gaining reach (Mill Pond) of the Sudbury River in Ashland, Massachusetts, with a temporary pushpoint sampler to determine whether this device is an effective tool for measuring small-scale spatial variations in concentrations of volatile organic compounds and selected field parameters (specific conductance and dissolved oxygen concentration). The pore waters sampled were within a subsurface plume of volatile organic compounds extending from the nearby Nyanza Chemical Waste Dump Superfund site to the river. Samples were collected from depths of 10, 30, and 60 centimeters below the sediment surface along two 10-meter-long, parallel transects extending into the river. Twenty-five volatile organic compounds were detected at concentrations ranging from less than 1 microgram per liter to hundreds of micrograms per liter (for example, 1,2-dichlorobenzene, 490 micrograms per liter; cis-1,2-dichloroethene, 290 micrograms per liter). The most frequently detected compounds were either chlorobenzenes or chlorinated ethenes. Many of the compounds were detected only infrequently. Quality-control sampling indicated a low incidence of trace concentrations of contaminants. Additional samples collected with passive-water-diffusion-bag samplers yielded results comparable to those collected with the pushpoint sampler and to samples collected in previous studies at the site. The results demonstrate that the pushpoint sampler can yield distinct samples from sites in close proximity; in this case, sampling sites were 1 meter apart horizontally and 20 or 30 centimeters apart vertically. Moreover, the pushpoint sampler was able to draw pore water when inserted to depths as shallow as 10 centimeters below the sediment surface without entraining surface water. The simplicity of collecting numerous samples in a short time period (routinely, 20 to 30 per day) validates the use of a

  9. Mutagenicity of drinking water sampled from the Yangtze River and Hanshui River (Wuhan section) and correlations with water quality parameters.

    PubMed

    Lv, Xuemin; Lu, Yi; Yang, Xiaoming; Dong, Xiaorong; Ma, Kunpeng; Xiao, Sanhua; Wang, Yazhou; Tang, Fei

    2015-03-31

    A total of 54 water samples were collected during three different hydrologic periods (level period, wet period, and dry period) from Plant A and Plant B (a source for Yangtze River and Hanshui River water, respectively), and several water parameters, such as chemical oxygen demand (COD), turbidity, and total organic carbon (TOC), were simultaneously analyzed. The mutagenicity of the water samples was evaluated using the Ames test with Salmonella typhimurium strains TA98 and TA100. According to the results, the organic compounds in the water were largely frame-shift mutagens, as positive results were found for most of the tests using TA98. All of the finished water samples exhibited stronger mutagenicity than the relative raw and distribution water samples, with water samples collected from Plant B presenting stronger mutagenic strength than those from Plant A. The finished water samples from Plant A displayed a seasonal-dependent variation. Water parameters including COD (r = 0.599, P = 0.009), TOC (r = 0.681, P = 0.02), UV254 (r = 0.711, P = 0.001), and total nitrogen (r = 0.570, P = 0.014) exhibited good correlations with mutagenicity (TA98), at 2.0 L/plate, which bolsters the argument of the importance of using mutagenicity as a new parameter to assess the quality of drinking water.

  10. Mutagenicity of drinking water sampled from the Yangtze River and Hanshui River (Wuhan section) and correlations with water quality parameters

    PubMed Central

    Lv, Xuemin; Lu, Yi; Yang, Xiaoming; Dong, Xiaorong; Ma, Kunpeng; Xiao, Sanhua; Wang, Yazhou; Tang, Fei

    2015-01-01

    A total of 54 water samples were collected during three different hydrologic periods (level period, wet period, and dry period) from Plant A and Plant B (a source for Yangtze River and Hanshui River water, respectively), and several water parameters, such as chemical oxygen demand (COD), turbidity, and total organic carbon (TOC), were simultaneously analyzed. The mutagenicity of the water samples was evaluated using the Ames test with Salmonella typhimurium strains TA98 and TA100. According to the results, the organic compounds in the water were largely frame-shift mutagens, as positive results were found for most of the tests using TA98. All of the finished water samples exhibited stronger mutagenicity than the relative raw and distribution water samples, with water samples collected from Plant B presenting stronger mutagenic strength than those from Plant A. The finished water samples from Plant A displayed a seasonal-dependent variation. Water parameters including COD (r = 0.599, P = 0.009), TOC (r = 0.681, P = 0.02), UV254 (r = 0.711, P = 0.001), and total nitrogen (r = 0.570, P = 0.014) exhibited good correlations with mutagenicity (TA98), at 2.0 L/plate, which bolsters the argument of the importance of using mutagenicity as a new parameter to assess the quality of drinking water. PMID:25825837

  11. Statistical analysis of stream water-quality data and sampling network design near Oklahoma City, central Oklahoma, 1977-1999

    USGS Publications Warehouse

    Brigham, Mark E.; Payne, Gregory A.; Andrews, William J.; Abbott, Marvin M.

    2002-01-01

    The sampling network was evaluated with respect to areal coverage, sampling frequency, and analytical schedules. Areal coverage could be expanded to include one additional watershed that is not part of the current network. A new sampling site on the North Canadian River might be useful because of expanding urbanization west of the city, but sampling at some other sites could be discontinued or reduced based on comparisons of data between the sites. Additional real-time or periodic monitoring for dissolved oxygen may be useful to prevent anoxic conditions in pools behind new low-water dams. The sampling schedules, both monthly and quarterly, are adequate to evaluate trends, but additional sampling during flow extremes may be needed to quantify loads and evaluate water-quality during flow extremes. Emerging water-quality issues may require sampling for volatile organic compounds, sulfide, total phosphorus, chlorophyll-a, Esherichia coli, and enterococci, as well as use of more sensitive laboratory analytical methods for determination of cadmium, mercury, lead, and silver.

  12. Validation of a non-invasive blood-sampling technique for doubly-labelled water experiments.

    PubMed

    Voigt, Christian C; Helversen, Otto Von; Michener, Robert H; Kunz, Thomas H

    2003-04-01

    Two techniques for bleeding small mammals have been used in doubly-labeled water (DLW) studies, including vena puncture and the use of starved nymphal stages of hematophagous reduviid bugs (Reduviidae, Hemiptera). In this study, we tested the validity of using reduviid bugs in doubly-labeled water experiments. We found that the isotope enrichment in initial blood samples collected with bugs was significantly lower compared to isotope enrichment in blood samples obtained using vena puncture. We therefore used the desiccation method for estimating total body water (TBW) in DLW experiments because TBW calculated using the isotope dilution method was overestimated when blood samples were collected using reduviid bugs. In our validation experiment with nectar-feeding bats (Glossophaga soricina), we compared estimates of daily energy expenditure (DEE) using DLW with those derived from the energy balance method. We considered Speakman's equation (controlling for 25% fractionated water loss) as the most appropriate for our study animal and calculated DEE accordingly. On average, DEE estimated with DLW was not significantly different from the mean value obtained with the energy balance method (mean deviation 1.2%). We conclude that although bug hemolymph or intestinal liquids most likely contaminate the samples, estimates of DEE are still valid because the DLW method does not depend on absolute isotope enrichments but on the rate of isotope decrease over time. However, dilution of blood with intestinal liquids or hemolymph from a bug may lead to larger variation in DEE estimates. We also tested how the relative error of DLW estimates changed with varying assumptions about fractionation. We used three additional equations for calculating DEE in DLW experiments. The basic equation for DLW experiments published by Lifson and McClintock (LM-6) assumes no fractionation, resulted in an overestimate of DEE by 10%. Nagy's equation (N-2) controls for changes in body mass but not for

  13. Suppression of methane/air explosion by ultrafine water mist containing sodium chloride additive.

    PubMed

    Cao, Xingyan; Ren, Jingjie; Zhou, Yihui; Wang, Qiuju; Gao, Xuliang; Bi, Mingshu

    2015-03-21

    The suppression effect of ultrafine mists on methane/air explosions with methane concentrations of 6.5%, 8%, 9.5%, 11%, and 13.5% were experimentally studied in a closed visual vessel. Ultrafine water/NaCl solution mist as well as pure water mist was adopted and the droplet sizes of mists were measured by phase doppler particle analyzer (PDPA). A high speed camera was used to record the flame evolution processes. In contrast to pure water mist, the flame propagation speed, the maximum explosion overpressure (ΔP(max)), and the maximum pressure rising rate ((dP/dt)max) decreased significantly, with the "tulip" flame disappearing and the flame getting brighter. The results show that the suppressing effect on methane explosion by ultrafine water/NaCl solution mist is influenced by the mist amount and methane concentration. With the increase of the mist amount, the pressure, and the flame speed both descended significantly. And when the mist amount reached 74.08 g/m(3) and 37.04 g/m(3), the flames of 6.5% and 13.5% methane explosions can be absolutely suppressed, respectively. All of results indicate that addition of NaCl can improve the suppression effect of ultrafine pure water mist on the methane explosions, and the suppression effect is considered due to the combination effect of physical and chemical inhibitions.

  14. Demonstration/Validation of the Snap Sampler Passive Ground Water Sampling Device

    DTIC Science & Technology

    2011-06-01

    sampling 5. Carefully selecting a sampling order that reduces sampler impacts on subsequent sampling events. 6.1.2 Baseline Characterization Prior to...sampling • Carefully selecting a sampling order that reduces sampler impacts on subsequent sampling events. 27 6.2.2 Baseline...Validation of the Snap Sampler Passive Ground Water Sampling Device June 2011 i COST & PERFORMANCE REPORT Project: ER-200630 TABLE OF CONTENTS

  15. Gasbuggy, New Mexico, Natural Gas and Produced Water Sampling Results for 2012

    SciTech Connect

    2012-12-01

    The U.S. Department of Energy (DOE) Office of Legacy Management conducted annual natural gas sampling for the Gasbuggy, New Mexico, Site on June 20 and 21, 2012. This long-term monitoring of natural gas includes samples of produced water from gas production wells that are located near the site. Water samples from gas production wells were analyzed for gamma-emitting radionuclides, gross alpha, gross beta, and tritium. Natural gas samples were analyzed for tritium and carbon-14. ALS Laboratory Group in Fort Collins, Colorado, analyzed water samples. Isotech Laboratories in Champaign, Illinois, analyzed natural gas samples.

  16. A comparison of additional treatment processes to limit particle accumulation and microbial growth during drinking water distribution.

    PubMed

    Liu, G; Lut, M C; Verberk, J Q J C; Van Dijk, J C

    2013-05-15

    Water quality changes, particle accumulation and microbial growth occurring in pilot-scale water distribution systems fed with normally treated and additional treated groundwater were monitored over a period of almost one year. The treatment processes were ranked in the following order: nanofiltration (NF) > (better than) ultrafiltration (UF) > ion exchange (IEX) for limiting particle accumulation. A different order was found for limiting overall microbial growth: NF > IEX > UF. There were strong correlations between particle load and particle accumulation, and between nutrient load and microbial growth. It was concluded that particle accumulation can be controlled by reducing the particle load in water treatment plants; and the microbial growth can be better controlled by limiting organic nutrients rather than removing biomass in water treatment plants. The major focus of this study was on microbial growth. The results demonstrated that growth occurred in all types of treated water, including the phases of bulk water, biofilm and loose deposits. Considering the growth in different phases, similar growth in bulk water was observed for all treatments; NF strongly reduced growth both in loose deposits and in biofilm; UF promoted growth in biofilm, while strongly limiting growth in loose deposits. IEX had good efficiency in between UF and NF, limiting both growths in loose deposits and in biofilm. Significant growth was found in loose deposits, suggesting that loose deposit biomass should be taken into account for growth evaluation and/or prediction. Strong correlations were found between microbial growth and pressure drop in a membrane fouling simulator which proved that a membrane fouling simulator can be a fast growth predictor (within a week). Different results obtained by adenosine triphosphate and flow cytometry cell counts revealed that ATP can accurately describe both suspended and particle-associated biomass, and flow cytometry files of TCC measurements needs

  17. Retardation of crystallization-induced destabilization of PMF-in-water emulsion with emulsifier additives.

    PubMed

    Arima, Satoshi; Ueji, Toshiyuki; Ueno, Satoru; Ogawa, Akihiro; Sato, Kiyotaka

    2007-03-15

    An oil-in-water (O/W) emulsion, in which the oil phase is semi-solid fat, is easily destabilized when stored below the crystallization temperature of the oil phase. Such destabilization, characterized by loss of fluidity at chilled temperature and oil-water separation after re-heating, is caused by inter-droplet bridging of fat crystals protruding out of the emulsion droplets. In the present study, we found that the simultaneous use of additives of highly hydrophobic sucrose oligoester (SOE; P-170) and highly hydrophilic SOE (P-1670) containing palmitic acid moiety remarkably retarded the crystallization-induced destabilization of the O/W emulsion that contains palm-mid-fraction (PMF) as the oil phase. Without the additives, destabilization occurred when the emulsion was cooled from 60 to 0 degrees C and kept at 0 degrees C for 1 day. Microscopic observation revealed that destabilization was caused by coalescence of the oil droplets, which was triggered by the growth of needle-shaped PMF crystals protruding out of the emulsion membranes. However, the addition of P-170 to PMF increased the crystallization temperature of PMF and at the same time retarded the destabilization. Furthermore, the simultaneous addition of P-170 and P-1670 retarded the crystallization-induced destabilization even more. Optical observation, DSC, and synchrotron radiation X-ray diffraction measurements indicated that the P-170 additive enhanced interfacial heterogeneous crystallization to form tiny PMF crystals in the droplets, and that the P-1670 additive retarded morphological change of the PMF crystals into long needle shapes in association with polymorphic transformation from alpha to beta'.

  18. Sample Return from Water Worlds: Requirements, Risks, and Enabling Technologies

    NASA Astrophysics Data System (ADS)

    Venkatapathy, E.; Gage, P.; Munk, M.; Ellerby, D.; Stackpoole, M.

    2017-02-01

    Planetary protection requirements make sample return missions from Mars, Enceladus, Titan, and Europa a grand challenge for entry, descent, and landing. Ways to address the challenges are explored with emerging new technologies.

  19. METALS IN GROUND WATER: SAMPLING ARTIFACTS AND REPRODUCIBILITY

    EPA Science Inventory

    Field studies evaluated sampling procedures for determination of aqueous inorganic geochemistry and assessment of contaminant transport by colloidal mobility. esearch at three different metal-contaminated sites has shown that 0.45 tm filtration has not removed potentially mobile ...

  20. EVALUATION OF FISH SAMPLING DESIGNS FOR COASTAL WATERS

    EPA Science Inventory

    Because no objective assessment of fish sampling methodologies has been completed for Great Lakes coastal wetlands we evaluated catches from several techniques and studies to determine the most effective combinations for these habitats. Data from six underdeveloped sites in Green...

  1. Characterization of paint samples used in drinking water reservoirs: identification of endocrine disruptor compounds.

    PubMed

    Romero, J; Ventura, F; Gomez, M

    2002-04-01

    Several migration tests are performed from various epoxy paint samples that, according to the regulation, can be used in food reservoirs such as drinking water reservoirs. The level of the organic compounds capable of producing migrations to water with special attention to endocrine disruptor compounds (EDCs) are identified and estimated by closed loop-stripping analysis (CLSA) and liquid-liquid extraction (LLE) methods coupled with gas chromatography (GC)-mass spectrometry (MS). Bisphenol A, a strong endocrine disruptor, is found in all migration experiments. Its concentration level reaches between 0.02 and 0.03 mg/cm2. The higher concentration corresponds with benzylic alcohol, which is used as a solvent and curing agent in epoxy paint. Other EDCs identified in the migration tests are phthalates, 4-nonylphenol, and t-butylphenol. The main non-EDCs identified are solvents, antioxidants, and rubber-like compounds. No great differences are found in the use of metallic plates or concrete slabs for migration experiments; only additional compounds related with the pretreatment of the concrete wall have been identified, too. In the study of a drinking water sample the same organic compounds identified in the migration test is not seen. This is probably because of the dynamic situation in a drinking water reservoir. Finally, a GC profile of a direct epoxy paint analysis is shown. The main peak identified is bisphenol A diglycidyl ether, monomer, and an active principle of the polymerization of epoxy resins based on bisphenol A. In addition, we report the recoveries of a selected group of EDCs using CLSA and LLE methods coupled with GC-MS.

  2. Reconnaissance water sampling for radium-226 in central and northern Florida, December 1974-March 1976

    USGS Publications Warehouse

    Irwin, G.A.; Hutchinson, C.B.

    1976-01-01

    Analyses of 115 water samples collected from December 1974 through March 1976 in eight Florida Counties indicated that 22 samples (19 percent) had radium-226 activities equal to or in excess of 3 piC/liter (picocuries per liter), the concentration limit recommended for drinking water by the U.S. Public Health Service. The maximum radium-226 activity was 90 piC/liter in water from a shallow well in Polk County. The sampling reconnaissance was generally limited to areas of active phosphate mining and areas of undisturbed phosphate deposits. Most of the sampling was from water wells. Thirteen surface-water samples were collected in the Peace River drainage basin. The maximum radium-226 detected in surface-water samples was 3.6 piC/liter in Little Charlie Creek at State Road 664A in Hardee County. (Woodard-USGS)

  3. Water quality and heavy metal monitoring in water and sediment samples of the Küçükçekmece Lagoon, Turkey (2002-2003).

    PubMed

    Altun, Omer; Saçan, Melek Türker; Erdem, Ayten Kimiran

    2009-04-01

    Physical and chemical parameters have been analyzed in water samples from a brackish water lagoon, Küçükçekmece, located on the western outskirts of Istanbul. Samples were collected every two months for a year from nine sampling stations. Of the parameters measured, temperature, pH, salinity, nitrate and phosphate showed changes when compared with the previously published data. The lagoon was found eutrophic as it was reported previously. Sulphate and COD levels were higher when compared with the standards established by the Turkish Water Pollution and Control Regulation. Additionally, concentrations of heavy metals (Cd, Co, Cr, Cu, Mn, Ni, Pb, Zn) in water and bottom sediments were measured and compared with the standards established by the Turkish Water Pollution and Control Regulation and with the previously published data. The results were analysed statistically with respect to location and any relationships between the concentration of the elements in corresponding water and sediment samples were examined. Principal Component Analysis of water samples allowed us to discriminate three areas affected mainly by heavy metal contamination, possibly due to industrial, commercial and/or urban activities. Generally, the concentrations of the heavy metals were higher at stations near the three estuaries, suggesting a direct influence of the three creeks on the pollution of the Küçükçekmece Lagoon. Although elevated levels of Cd were recorded in several water samples, it was not detected in sediment. On the other hand, a particularly high level of Cr pollution was recorded most of the water and sediment samples.

  4. MICROBIOLOGICAL FIELD SAMPLING AND INSTRUMENTATION IN THE ASSESSMENT OF SOIL AND GROUND-WATER POLLUTION

    EPA Science Inventory

    This chapter emphasizes the importance of microbiological sampling of soil and ground water with respect to human heath risks, laws and regulations dealing with safe drinking water, and more prevalent subsurface monitoring activities associated with chlorinated organic compounds,...

  5. EPA Technology Available for Licensing: Portable Device to Concentrate Water Samples for Microorganism Analysis

    EPA Pesticide Factsheets

    Using a computer controlled system, this ultrafiltration device automates the process of concentrating a water sample and can be operated in the field. The system was also designed to reduce human exposure to potentially contaminated water.

  6. PORTABLE ULTRAFILTRATION DEVICE FOR CONCENTRATION PATHOGENS FROM LARGE VOUME SAMPLES OF DRINKING WATER

    EPA Science Inventory

    Symposium Paper in proceedings of Water Security Congress, Washington, D.C., 12 Sep 2006 - Development and testing of several potential protocols utilizing ultrafiltration to collect and concentrate microorganisms from large volume water samples.

  7. Additional variability at the D12S391 STR locus in an Austrian population sample: sequencing data and allele distribution.

    PubMed

    Glock, B; Dauber, E M; Schwartz, D W; Mayr, W R

    1997-12-01

    The highly polymorphic STR locus D12S391 was investigated in an Austrian population sample (N = 150) by PCR-amplification, comparative detection on native and denaturing polyacrylamide gels and solid phase single stranded sequencing of three size variant alleles and several additional alleles. A total of 15 alleles, distinguishable by size under denaturing conditions, could be detected. No deviations from Hardy-Weinberg equilibrium were observed in the population investigated (P = 0.52). Sequencing of size variants designated 17.3 and 18.3 showed an incomplete (GAT) repeat unit at position two of the tandem region. Additional new sequence variants due to varying compositions of the number of (AGAT) and (AGAC) repeats could be identified. Due to distinct electrophoretical mobilities of alleles of the same size but different sequence structures, denaturing detection conditions should be employed when the aim is standardization.

  8. Odour and flavour thresholds of gasoline additives (MTBE, ETBE and TAME) and their occurrence in Dutch drinking water collection areas.

    PubMed

    van Wezel, Annemarie; Puijker, Leo; Vink, Cees; Versteegh, Ans; de Voogt, Pim

    2009-07-01

    The use of ETBE (ethyl-tert-butylether) as gasoline additive has recently grown rapidly. Contamination of aquatic systems is well documented for MTBE (methyl-tert-butylether), but less for other gasoline additives. Due to their mobility they may easily reach drinking water collection areas. Odour and flavour thresholds of MTBE are known to be low, but for ETBE and TAME (methyl-tert-amylether) hardly information is available. The objective here is to determine these thresholds for MTBE, ETBE and TAME, and relate these to concentrations monitored in thousands of samples from Dutch drinking water collection areas. For ETBE odour and flavour thresholds are low with 1-2microgL(-1), for MTBE and TAME they range from 7 to 16microg L(-1). In most groundwater collection areas MTBE concentrations are below 0.1microg L(-1). In phreatic groundwaters in sandy soils not covered by a protective soil layer, occasionally MTBE occurs at higher concentrations. For surface water collection areas a minority of the locations is free of MTBE. For river bank and dune infiltrates, at a few locations the odour and flavour threshold is exceeded. For ETBE fewer monitoring data are available. ETBE was found in 2 out of 37 groundwater collection areas, in concentrations below 1microgL(-1). In the surface water collection areas monitored ETBE was found in concentrations near to the odour and flavour thresholds. The low odour and flavour thresholds combined with the high mobility and persistence of these compounds, their high production volumes and their increased use may yield problems with future production of drinking water.

  9. High-frequency isotopic analysis of liquid water samples in the field - initial results from continuous water sampling and cavity ring-down spectroscopy

    NASA Astrophysics Data System (ADS)

    von Freyberg, Jana; Studer, Bjørn; Kirchner, James

    2016-04-01

    Studying rapidly changing hydrochemical signals in catchments can help to improve our mechanistic understanding of their water flow pathways and travel times. For these purposes, stable water isotopes (18O and 2H) are commonly used as natural tracers. However, high-frequency isotopic analyses of liquid water samples are challenging. One must capture highly dynamic behavior with high precision and accuracy, but the lab workload (and sample storage artifacts) involved in collecting and analyzing thousands of bottled samples should also be avoided. Therefore, we have tested Picarro, Inc.'s newly developed Continuous Water Sampler Module (CoWS), which is coupled to their L2130-i Cavity Ring-Down Spectrometer to enable real-time on-line measurements of 18O and 2H in liquid water samples. We coupled this isotope analysis system to a dual-channel ion chomatograph (Metrohm AG, Herisau, Switzerland) for analysis of major cations and anions, as well as a UV-Vis spectroscopy system (s::can Messtechnik GmbH, Vienna, Austria) and electrochemical probes for characterization of basic water quality parameters. The system was run unattended for up to a week at a time in the laboratory and at a small catchment. At the field site, stream-water and precipitation samples were analyzed, alternating at sub-hourly intervals. We observed that measured isotope ratios were highly sensitive to the liquid water flow rate in the CoWS, and thus to the hydraulic head difference between the CoWS and the samples from which water was drawn. We used a programmable high-precision dosing pump to control the injection flow rate and eliminate this flow-rate artifact. Our experiments showed that the precision of the CoWS-L2130-i-system for 2-minute average values was typically better than 0.06‰ for δ18O and 0.16‰ for δ2H. Carryover effects were 1% or less between isotopically contrasting water samples for 30-minute sampling intervals. Instrument drift could be minimized through periodic analysis of

  10. June 2011 Natural Gas and Produced Water Sampling at the Gasbuggy, New Mexico, Site

    SciTech Connect

    2011-10-01

    Annual natural gas and produced water monitoring was conducted for gas wells adjacent to Section 36, where the Gasbuggy test was conducted, in accordance with the draft Long-Term Surveillance and Maintenance Plan for the Gasbuggy Site, Rio Arriba County, New Mexico. Sampling and analysis were conducted as specified in the Sampling and Analysis Plan for U.S. Department of Energy Office of Legacy Management Sites (LMS/PLN/S04351, continually updated). Natural gas samples were collected for tritium and carbon-14 analyses. Produced water samples were collected and analyzed for tritium, gamma-emitting radionuclides (by high-resolution gamma spectrometry), gross alpha, and gross beta. A duplicate produced water sample was collected from well 30-039-21743. Produced water samples were not collected at locations 30-039-30161 and 30-039-21744 because of the lack of water. Samples were not collected from location 30-039-29988 because the well was shut-in.

  11. UMTRA Project water sampling and analysis plan, Grand Junction, Colorado. Revision 1, Version 6

    SciTech Connect

    1995-09-01

    This water sampling and analysis plan describes the planned, routine ground water sampling activities at the Grand Junction US DOE Uranium Mill Tailings Remedial Action (UMTRA) Project site (GRJ-01) in Grand Junction, Colorado, and at the Cheney Disposal Site (GRJ-03) near Grand Junction. The plan identifies and justifies the sampling locations, analytical parameters, detection limits, and sampling frequencies for the routine monitoring stations at the sites. Regulatory basis is in the US EPA regulations in 40 CFR Part 192 (1994) and EPA ground water quality standards of 1995 (60 FR 2854). This plan summarizes results of past water sampling activities, details water sampling activities planned for the next 2 years, and projects sampling activities for the next 5 years.

  12. Occurrence of Cryptosporidium sp. oocysts in fecal and water samples in Austria.

    PubMed

    Hassl, A; Benyr, G; Sommer, R

    2001-10-22

    Oocysts of Cryptosporidium spp. were detected and differentiated by a modular arranged gene amplification procedure in various samples, mostly human stool, feces of herpetotaxa, and water, in different locations of South and Eastern Austria. Cryptosporidium parvum was found in stool samples of immunocompromised persons, in reptile feces, and in water samples. The presence of Cryptosporidium in an area is probably associated with high human population densities since water from protected sources in sparsely inhabited areas is rarely contaminated.

  13. Enhancement of nitrate removal at the sediment-water interface by carbon addition plus vertical mixing.

    PubMed

    Chen, Xuechu; He, Shengbing; Zhang, Yueping; Huang, Xiaobo; Huang, Yingying; Chen, Danyue; Huang, Xiaochen; Tang, Jianwu

    2015-10-01

    Wetlands and ponds are frequently used to remove nitrate from effluents or runoffs. However, the efficiency of this approach is limited. Based on the assumption that introducing vertical mixing to water column plus carbon addition would benefit the diffusion across the sediment-water interface, we conducted simulation experiments to identify a method for enhancing nitrate removal. The results suggested that the sediment-water interface has a great potential for nitrate removal, and the potential can be activated after several days of acclimation. Adding additional carbon plus mixing significantly increases the nitrate removal capacity, and the removal of total nitrogen (TN) and nitrate-nitrogen (NO3(-)-N) is well fitted to a first-order reaction model. Adding Hydrilla verticillata debris as a carbon source increased nitrate removal, whereas adding Eichhornia crassipe decreased it. Adding ethanol plus mixing greatly improved the removal performance, with the removal rate of NO3(-)-N and TN reaching 15.0-16.5 g m(-2) d(-1). The feasibility of this enhancement method was further confirmed with a wetland microcosm, and the NO3(-)-N removal rate maintained at 10.0-12.0 g m(-2) d(-1) at a hydraulic loading rate of 0.5 m d(-1).

  14. Poly(ether ester) Ionomers as Water-Soluble Polymers for Material Extrusion Additive Manufacturing Processes.

    PubMed

    Pekkanen, Allison M; Zawaski, Callie; Stevenson, André T; Dickerman, Ross; Whittington, Abby R; Williams, Christopher B; Long, Timothy E

    2017-04-12

    Water-soluble polymers as sacrificial supports for additive manufacturing (AM) facilitate complex features in printed objects. Few water-soluble polymers beyond poly(vinyl alcohol) enable material extrusion AM. In this work, charged poly(ether ester)s with tailored rheological and mechanical properties serve as novel materials for extrusion-based AM at low temperatures. Melt transesterification of poly(ethylene glycol) (PEG, 8k) and dimethyl 5-sulfoisophthalate afforded poly(ether ester)s of sufficient molecular weight to impart mechanical integrity. Quantitative ion exchange provided a library of poly(ether ester)s with varying counterions, including both monovalent and divalent cations. Dynamic mechanical and tensile analysis revealed an insignificant difference in mechanical properties for these polymers below the melting temperature, suggesting an insignificant change in final part properties. Rheological analysis, however, revealed the advantageous effect of divalent countercations (Ca(2+), Mg(2+), and Zn(2+)) in the melt state and exhibited an increase in viscosity of two orders of magnitude. Furthermore, time-temperature superposition identified an elevation in modulus, melt viscosity, and flow activation energy, suggesting intramolecular interactions between polymer chains and a higher apparent molecular weight. In particular, extrusion of poly(PEG8k-co-CaSIP) revealed vast opportunities for extrusion AM of well-defined parts. The unique melt rheological properties highlighted these poly(ether ester) ionomers as ideal candidates for low-temperature material extrusion additive manufacturing of water-soluble parts.

  15. Dendrite-Free Li Deposition Using Trace-Amounts of Water as an Electrolyte Additive

    SciTech Connect

    Qian, Jiangfeng; Xu, Wu; Bhattacharya, Priyanka; Engelhard, Mark H.; Henderson, Wesley A.; Zhang, Yaohui; Zhang, Jiguang

    2015-07-01

    Residual water presents in nonaqueous electrolytes has been widely regarded as a detrimental factor for lithium (Li) batteries. This is because water is highly reactive with the commonly used LiPF6 salt and leads to the formation of HF that corrodes battery materials. In this work, we demonstrate that a controlled trace-amount of water (25-100 ppm) can be an effective electrolyte additive for achieving dendrite-free Li metal deposition in LiPF6-based electrolytes and avoid its detrimental effect at the same time. Detailed analyses reveal that the trace amount of HF formed by the decomposition reaction of LiPF6 with water will be electrochemically reduced during initial Li deposition process to form a uniform and dense LiF-rich SEI layer on the surface of the substrate. This LiF-rich SEI layer leads to a uniform distribution of the electric field on the substrate surface and enables uniform and dendrite-free Li deposition. Meanwhile the detrimental effect of HF is diminished due to the consumption of HF in the LiF formation process. Microscopic analysis reveals that the as-deposited dendrite-free Li films exhibit a self-aligned and highly-compacted Li nanorods structure which is consistent with their charming blue color or known as structure color. These findings clearly demonstrate a novel approach to control the nucleation and grow process of Li metal films using well-controlled trace-amount of water. They also shine the light on the effect of water on other electrodeposition processes.

  16. UMTRA Project water sampling and analysis plan, Gunnison, Colorado: Revision 1

    SciTech Connect

    Not Available

    1994-11-01

    This water sampling and analysis plan summarizes the results of previous water sampling activities and the plan for future water sampling activities, in accordance with the Guidance Document for Preparing Sampling and Analysis Plans for UMTRA Sites. A buffer zone monitoring plan for the Dos Rios Subdivision is included as an appendix. The buffer zone monitoring plan was developed to ensure continued protection to the public from residual contamination. The buffer zone is beyond the area depicted as contaminated ground water due to former milling operations. Surface remedial action at the Gunnison Uranium Mill Tailings Remedial Action Project site began in 1992; completion is expected in 1995. Ground water and surface water will be sampled semiannually at the Gunnison processing site and disposal site. Results of previous water sampling at the Gunnison processing site indicate that ground water in the alluvium is contaminated by the former uranium processing activities. Background ground water conditions have been established in the uppermost aquifer at the Gunnison disposal site. The monitor well locations provide a representative distribution of sampling points to characterize ground water quality and ground water flow conditions in the vicinity of the sites. The list of analytes has been modified with time to reflect constituents that are related to uranium processing activities and the parameters needed for geochemical evaluation.

  17. The representativeness of pore water samples collected from the unsaturated zone using pressure-vacuum lysimeters

    USGS Publications Warehouse

    Peters, C.A.; Healy, R.W.

    1988-01-01

    Studies have indicated that the chemistry of water samples may be altered by the collection technique, creating concern about the representativeness of the pore water samples obtained. A study using soil water pressure-vacuum lysimeters in outwash sand and glacial till deposits demonstrates that for non-dilute-solution samples the effect of pH of sampling with lysimeters is minimal, and that measured major cation and anion concentrations are representative of the natural pore water; trace-metal concentrations can be significantly altered by collection procedures at low concentrations. -from Authors

  18. Conservation of phage reference materials and water samples containing bacteriophages of enteric bacteria.

    PubMed

    Mendez, J; Jofre, J; Lucena, F; Contreras, N; Mooijman, K; Araujo, R

    2002-12-01

    The survival was determined in different conservation conditions of: somatic coliphages, F-specific RNA bacteriophages and phages infecting Bacteroides fragilis proposed as model micro-organisms for water quality control. Titres of phages of all groups either in pure culture phage suspensions or in naturally occurring phage suspensions were stable at (-70+/-10) degrees C and at (-20+/-5) degrees C when protected with glycerol. Moreover, phage analysis of stored suspensions demonstrated that their numbers were homogeneous, both between vials and within vials, and consequently they can be used as reference materials. Furthermore, changes in the storage temperature of the vials cause unpredictable changes in the numbers of bacteriophages. Consequently, phage reference materials and samples containing a quantitative number of phages must be maintained and dispatched at a constant temperature. Consequently, the results indicate that bacteriophages should be packed in dry ice during transport and storage. Finally, the number of phages in water samples stored at (5+/-3) degrees C in the dark does not decrease significantly during the first 72 h of storage. In addition, phage concentrates from natural samples obtained by adsorption-elution to cellulose nitrate filters and mixed with 10% glycerol were stable at least for 2 months at (-70+/-10) degrees C and at (-20+/-5) degrees C.

  19. Estimation of the hydrophobic fraction of dissolved organic matter in water samples using UV photometry.

    PubMed

    Dilling, Jörg; Kaiser, Klaus

    2002-12-01

    In this study, we tested a simple and rapid method for the estimation of carbon in the hydrophobic fraction of dissolved organic matter (DOM) of different origin (spruce, pine, and beech litter) in soil water. The method is based on the fact that the hydrophobic fraction of DOM contains almost entirely the aromatic moieties of DOM. Thus, it showed a clearly distinct light absorption at 260 nm compared to the hydrophilic fraction. This light absorption was directly proportional to the concentration of the hydrophobic fraction. Moreover, it was independent of the concentration of the hydrophilic fraction. We compared the concentrations of hydrophobic DOM estimated by the UV method with those of the conventional fractionation using chromatographic columns of XAD-8 macroporous resin and found an excellent agreement between the two methods for both solutions from laboratory sorption experiments and field samples of forest floor leachates and subsoil porewaters. In addition, the absorption at 260 nm of hydrophobic DOM proved to be independent of pH values ranging from 2.0 to 6.5. Compared to the conventional chromatographic fractionation, the method using the UV absorption at 260 nm is less time consuming, needs a much smaller sample volume, and showed a better reproducibility. However, its use is restricted to water samples of low nitrate (< 25 mg L(-1)) and Fe (< 5 mg L(-1)) concentrations and, probably, with the hydrophobic fraction dominated by aromatic compounds deriving from degradation of lignin.

  20. IMPROVED METHOD FOR THE STORAGE OF GROUND WATER SAMPLES CONTAINING VOLATILE ORGANIC ANALYTES

    EPA Science Inventory

    The sorption of volatile organic analytes from water samples by the Teflon septum surface used with standard glass 40-ml sample collection vials was investigated. Analytes tested included alkanes, isoalkanes, olefins, cycloalkanes, a cycloalkene, monoaromatics, a polynuclear arom...

  1. Inhibition of Ostwald ripening in model beverage emulsions by addition of poorly water soluble triglyceride oils.

    PubMed

    McClements, David Julian; Henson, Lulu; Popplewell, L Michael; Decker, Eric Andrew; Choi, Seung Jun

    2012-01-01

    Beverage emulsions containing flavor oils that have a relatively high water-solubility are unstable to droplet growth due to Ostwald ripening. The aim of this study was to improve the stability of model beverage emulsions to this kind of droplet growth by incorporating poorly water-soluble triglyceride oils. High pressure homogenization was used to prepare a series of 5 wt% oil-in-water emulsions stabilized by modified starch that had different lipid phase compositions (orange oil : corn oil). Emulsions prepared using only orange oil as the lipid phase were highly unstable to droplet growth during storage, which was attributed to Ostwald ripening resulting from the relatively high water-solubility of orange oil. Droplet growth could be effectively inhibited by incorporating ≥ 10% corn oil into the lipid phase prior to homogenization. In addition, creaming was also retarded because the lipid phase density was closer to that of the aqueous phase density. These results illustrate a simple method of improving the physical stability of orange oil emulsions for utilization in the food, beverage, and fragrance industries.

  2. The Influence of Pumping on Observed Bacterial Counts in Groundwater Samples: Implications for Sampling Protocol and Water Quality Interpretation

    NASA Astrophysics Data System (ADS)

    Kozuskanich, J.; Novakowski, K.; Anderson, B.

    2008-12-01

    Drinking water quality has become an important issue in Ontario following the events in Walkerton in 2000. Many rural communities are reliant on private groundwater wells for drinking water, and it is the responsibility of the owner to have the water tested to make sure it is safe for human consumption. Homeowners can usually take a sample to the local health unit for total coliform and E. Coli analysis at no charge to determine if the water supply is being tainted by surface water or fecal matter, both of which could indicate the potential for negative impacts on human health. However, is the sample coming out of the tap representative of what is going on the aquifer? The goal of this study is to observe how bacterial counts may vary during the course of well pumping, and how those changing results influence the assessment of water quality. Multiple tests were conducted in bedrock monitoring wells to examine the influence of pumping rate and pumped volume on observed counts of total coliform, E. Coli, fecal streptococcus, fecal coliform and heterotrophic plate count. Bacterial samples were collected frequently during the course of continuous purging events lasting up to 8 hours. Typical field parameters (temperature, salinity, pH, dissolved oxygen and ORP) were also continuously monitored during the course of each test. Common practice in groundwater studies is to wait until these parameters have stabilized or three well volumes have been removed prior to sampling, to ensure the sample is taken from new water entering the well from the aquifer, rather than the original water stored in the borehole prior to the test. In general, most bacterial counts were low, but did go above the drinking water standard of 0 counts/100mL (total coliform and E. Coli) at times during the tests. Results show the greatest variability in the observed bacterial counts at the onset of pumping prior to the removal of three well volumes. Samples taken after the removal of three well

  3. Water stable isotope measurements of Antarctic samples by means of IRMS and WS-CRDS techniques

    NASA Astrophysics Data System (ADS)

    Michelini, Marzia; Bonazza, Mattia; Braida, Martina; Flora, Onelio; Dreossi, Giuliano; Stenni, Barbara

    2010-05-01

    of the sample in the box. In the WS-CRDS the path of laser is longer, producing higher-sensitivity measurements. The instrument is paired with an autosampler and can be used without it and the vaporizer to analyze directly the isotopic composition of the water vapour in the atmosphere. In addition, the instrument can be moved from the laboratory and also used for outdoor measurements. The more important improvements over traditional IRMS techniques are that WS-CRDS needs less sample in order to perform the analysis (<2 ul vs. 3/5 ml); that it doesn't need manipulation of the sample (like the gas/water equilibration techniques) and the analyses are faster. Coversely, memory effects may affect the measurements so there is the need to increase the number of injection to have a high precision measurement. The laboratory of Isotope Geochemistry of the Department of Geosciences has recently acquired a WS-CRDS system from PICARRO. The isotopic data obtained with this new method have been compared with the ones obtained by means of IRMS methods. An HDO device coupled with a Thermo Finnigan Delta Plus Advantage mass spectrometer has been used, using the well know CO2 and H2/water equilibration technique. At the moment of the writing of the abstract the mean difference between the values obtained using PICARRO and using the traditional IRMS method is of the order of 0.1 per mil for the ratio 18O/16O and 1.00 per mil for the ratio D/H, but further measurements are currently underway. O'Keef A., Deacon D.A.G., 1988. Cavity ring-down optical spectrometer for absorption measurements using pulsed laser sources, Rev. Sci. Instrum., 59, 2544.

  4. 400 area secondary cooling water sampling and analysis plan

    SciTech Connect

    Penn, L.L.

    1996-10-29

    This is a total rewrite of the Sampling and Analysis Plan in response to, and to ensure compliance with, the State Waste Discharge Permit ST 4501 issued on July 31, 1996. This revision describes changes in facility status and implements requirements of the permit.

  5. Lake and river bottom sampling. (Latest citations from the Selected Water Resources Abstracts database). Published Search

    SciTech Connect

    Not Available

    1993-12-01

    The bibliography contains citations concerning techniques and results related to the collection of samples from the bottom of ponds, lakes, and rivers. Techniques include sampling devices, platforms for mounting or operating the sampling devices, and analytical techniques for the collected samples. Results include analysis of organic, chemical, and metallic components for bottom sediments. Statements on resulting water quality or environmental aspects are often included. Citations include investigations covering porosity of bottom soils, and ground water beneath the lake or river studied. Many of the samples include benthic fauna to assess the condition of the water. (Contains a minimum of 214 citations and includes a subject term index and title list.)

  6. Effects of nitrate addition on water column methylmercury in Occoquan Reservoir, Virginia, USA.

    PubMed

    Beutel, Marc W; Duvil, Ricardi; Cubas, Francisco J; Grizzard, Thomas J

    2017-03-01

    Mercury bioaccumulation in aquatic biota poses a widespread threat to human and environmental health. Methylmercury (MeHg), the toxic form of mercury, tends to build up under anaerobic conditions in the profundal zones of lakes. In this study we performed a two-year assessment of spatial and temporal patterns of dissolved oxygen, nitrate, MeHg, manganese (Mn) and iron (Fe) in Occoquan Reservoir, a large run-of-the-river drinking water reservoir in Virginia, USA. A tributary to the reservoir receives input of nitrate-rich tertiary-treated wastewater that enhances the oxidant capacity of bottom water. Multiple lines of evidence supported the hypothesis that the presences of nitrate and/or oxygen in bottom water correlated with low MeHg in bottom water. Bottom water MeHg was significantly lower in a nitrate-rich tributary (annual mean of 0.05 ng/L in both 2012 and 2013) compared to a nitrate-poor tributary (annual mean of 0.58 ng/L in 2012 and 0.21 ng/L in 2013). The presence of nitrate and oxygen in bottom water corresponded with significantly lower bottom water MeHg at an upstream station in the main reservoir (0.05 versus 0.11 ng/L in 2013). In 2012 the reservoir exhibited a longitudinal gradient with nitrate and oxygen decreasing and MeHg and Mn increasing downstream. In both study years, there was a clear threshold of oxygen equivalent (3-5 mg/L), a metric that combines the oxidant capacity of nitrate and oxygen, above which MeHg (<0.05 ng/L), Mn (<0.3 mg/L) and Fe (<0.5 mg/L) were low. Results indicated that the addition of nitrate-rich tertiary-treated wastewater to the bottom of anaerobic reservoirs can reduce MeHg concentrations, and potentially decrease mercury bioaccumulation, while increasing the safe water yield for potable use.

  7. Chloride in ground water and surface water in the vicinity of selected surface-water sampling sites of the beneficial use monitoring program of Oklahoma, 2003

    USGS Publications Warehouse

    Mashburn, Shana L.; Sughru, Michael P.

    2004-01-01

    The Oklahoma Water Resources Board Beneficial Use Monitoring Program reported exceedances of beneficial-use standards for chloride at 11 surface-water sampling sites from January to October 2002. The U.S. Geological Survey, in cooperation with the Oklahoma Department of Environmental Quality, conducted a study to determine the chloride concentrations in ground water in the vicinity of Beneficial Use Monitoring Program surface-water sampling sites not meeting beneficial use standards for chloride and compare chloride concentrations in ground water and surface water. The chloride-impaired Beneficial Use Monitoring Program surface-water sampling sites are located in the western and southern regions of Oklahoma. The ground-water sampling sites were placed in proximity to the 11 surface-water sampling sites designated impaired by chloride by the Oklahoma Water Resources Board. Two surface-water sampling sites were located on the Beaver River (headwaters of the North Canadian River), three sites on the Cimarron River, one site on Sandy Creek, one site on North Fork Red River, and four sites on the Red River. Six ground-water samples were collected, when possible, from two test holes located upstream from each of the 11 Beneficial Use Monitoring Program surface-water sampling sites. One test hole was placed on the left bank and right bank, when possible, of each Beneficial Use Monitoring Program surfacewater sampling site. All test holes were located on alluvial deposits adjacent to the Beneficial Use Monitoring Program surface-water sampling sites within 0.5 mile of the stream. Top, middle, and bottom ground-water samples were collected from the alluvium at each test hole, when possible. Water properties of specific conductance, pH, water temperature, and dissolved oxygen were recorded in the field before sampling for chloride. The ground-water median chloride concentrations at 8 of the 11 Beneficial Use Monitoring Program sites were less than the surface-water median

  8. Using Lagrangian sampling to study water quality during downstream transport in the San Luis Drain, California, USA

    USGS Publications Warehouse

    Volkmar, E.C.; Dahlgren, R.A.; Stringfellow, W.T.; Henson, S.S.; Borglin, S.E.; Kendall, C.; Van Nieuwenhuyse, E. E.

    2011-01-01

    To investigate the mechanism for diel (24h) changes commonly observed at fixed sampling locations and how these diel changes relate to downstream transport in hypereutrophic surface waters, we studied a parcel of agricultural drainage water as it traveled for 84h in a concrete-lined channel having no additional water inputs or outputs. Algal fluorescence, dissolved oxygen, temperature, pH, conductivity, and turbidity were measured every 30min. Grab samples were collected every 2h for water quality analyses, including nutrients, suspended sediment, and chlorophyll/pheophytin. Strong diel patterns were observed for dissolved oxygen, pH, and temperature within the parcel of water. In contrast, algal pigments and nitrate did not exhibit diel patterns within the parcel of water, but did exhibit strong diel patterns for samples collected at a fixed sampling location. The diel patterns observed at fixed sampling locations for these constituents can be attributed to algal growth during the day and downstream transport (washout) of algae at night. Algal pigments showed a rapid daytime increase during the first 48h followed by a general decrease for the remainder of the study, possibly due to sedimentation and photobleaching. Algal growth (primarily diatoms) was apparent each day during the study, as measured by increasing dissolved oxygen concentrations, despite low phosphate concentrations (<0.01mgL-1). ?? 2011 Elsevier B.V.

  9. GROUND-WATER SAMPLING BIAS OBSERVED IN SHALLOW, CONVENTIONAL WELLS

    EPA Science Inventory

    A previous field demonstration project on nitrate-based bioremediation of a fuel-contaminated aquifer used short-screened clustered well points in addition to shallow (10 foot), conventional monitoring wells to monitor the progress of remediation during surface application of rec...

  10. UMTRA Project water sampling and analysis plan, Belfield and Bowman, North Dakota

    SciTech Connect

    Not Available

    1994-08-01

    Surface remedial action is scheduled to begin at the Belfield and Bowman Uranium Mill Tailings Remedial Action (UMTRA) Project sites in the spring of 1996. Water sampling was conducted in 1993 at both the Belfield processing site and the Bowman processing/disposal site. Results of the sampling at both sites indicate that ground water conditions have remained relatively stable over time. Water sampling activities are not scheduled for 1994 because ground water conditions at the two sites are relatively stable, the 1993 sampling was comprehensive, and surface remediation activities are not scheduled to start until 1996. The next water sampling event is scheduled before the start of remedial activities and will include sampling selected monitor wells at both sites and several domestic wells in the vicinity.

  11. Sample volume optimization for radon-in-water detection by liquid scintillation counting.

    PubMed

    Schubert, Michael; Kopitz, Juergen; Chałupnik, Stanisław

    2014-08-01

    Radon is used as environmental tracer in a wide range of applications particularly in aquatic environments. If liquid scintillation counting (LSC) is used as detection method the radon has to be transferred from the water sample into a scintillation cocktail. Whereas the volume of the cocktail is generally given by the size of standard LSC vials (20 ml) the water sample volume is not specified. Aim of the study was an optimization of the water sample volume, i.e. its minimization without risking a significant decrease in LSC count-rate and hence in counting statistics. An equation is introduced, which allows calculating the ²²²Rn concentration that was initially present in a water sample as function of the volumes of water sample, sample flask headspace and scintillation cocktail, the applicable radon partition coefficient, and the detected count-rate value. It was shown that water sample volumes exceeding about 900 ml do not result in a significant increase in count-rate and hence counting statistics. On the other hand, sample volumes that are considerably smaller than about 500 ml lead to noticeably lower count-rates (and poorer counting statistics). Thus water sample volumes of about 500-900 ml should be chosen for LSC radon-in-water detection, if 20 ml vials are applied.

  12. Demonstration of the Gore Module for Passive Ground Water Sampling

    DTIC Science & Technology

    2014-06-01

    exposure period using a co-located (dedicated) submersible pump . (Samples were collected in 12-hour intervals so that a time-weighted average...Program (ESTCP), 4800 Mark Center Drive , Suite 17D08,Alexandria,VA,22350-3605 8. PERFORMING ORGANIZATION REPORT NUMBER 9. SPONSORING/MONITORING...APG Aberdeen Proving Ground ASTM ASTM International bgs below ground surface BNZ benzene BP bladder pump BTEX benzene, toluene, ethylbenzene

  13. Total and inorganic arsenic in fish samples from Norwegian waters.

    PubMed

    Julshamn, Kaare; Nilsen, Bente M; Frantzen, Sylvia; Valdersnes, Stig; Maage, Amund; Nedreaas, Kjell; Sloth, Jens J

    2012-01-01

    The contents of total arsenic and inorganic arsenic were determined in fillet samples of Northeast Artic cod, herring, mackerel, Greenland halibut, tusk, saithe and Atlantic halibut. In total, 923 individual fish samples were analysed. The fish were mostly caught in the open sea off the coast of Norway, from 40 positions. The determination of total arsenic was carried out by inductively coupled plasma mass spectrometry following microwave-assisted wet digestion. The determination of inorganic arsenic was carried out by high-performance liquid chromatography-ICP-MS following microwave-assisted dissolution of the samples. The concentrations found for total arsenic varied greatly between fish species, and ranged from 0.3 to 110 mg kg(-1) wet weight. For inorganic arsenic, the concentrations found were very low (<0.006 mg kg(-1)) in all cases. The obtained results question the assumptions made by the European Food Safety Authority (EFSA) on the inorganic arsenic level in fish used in the recent EFSA opinion on arsenic in food.

  14. Effect of water treatment additives on lime softening residual trace chemical composition--implications for disposal and reuse.

    PubMed

    Cheng, Weizhi; Roessler, Justin; Blaisi, Nawaf I; Townsend, Timothy G

    2014-12-01

    Drinking water treatment residues (WTR) offer potential benefits when recycled through land application. The current guidance in Florida, US allows for unrestricted land application of lime softening WTR; alum and ferric WTR require additional evaluation of total and leachable concentrations of select trace metals prior to land application. In some cases a mixed WTR is produced when lime softening is accompanied by the addition of a coagulant or other treatment chemical; applicability of the current guidance is unclear. The objective of this research was to characterize the total and leachable chemical content of WTR from Florida facilities that utilize multiple treatment chemicals. Lime and mixed lime WTR samples were collected from 18 water treatment facilities in Florida. Total and leachable concentrations of the WTR were measured. To assess the potential for disposal of mixed WTR as clean fill below the water table, leaching tests were conducted at multiple liquid to solid ratios and under reducing conditions. The results were compared to risk-based soil and groundwater contamination thresholds. Total metal concentrations of WTR were found to be below Florida soil contaminant thresholds with Fe found in the highest abundance at a concentration of 3600 mg/kg-dry. Aluminum was the only element that exceeded the Florida groundwater contaminant thresholds using SPLP (95% UCL = 0.23 mg/L; risk threshold = 0.2 mg/L). Tests under reducing conditions showed elevated concentrations of Fe and Mn, ranging from 1 to 3 orders of magnitude higher than SPLP leachates. Mixed lime WTR concentrations (total and leachable) were lower than the ferric and alum WTR concentrations, supporting that mixed WTR are appropriately represented as lime WTR. Testing of WTR under reducing conditions demonstrated the potential for release of certain trace metals (Fe, Al, Mn) above applicable regulatory thresholds; additional evaluation is needed to assess management options where

  15. Trace analysis of isothiazolinones in water samples by large-volume direct injection liquid chromatography tandem mass spectrometry.

    PubMed

    Speksnijder, P; van Ravestijn, J; de Voogt, P

    2010-08-06

    Isothiazolinones are used as preservatives, biocides and disinfectants in a variety of industrial and domestic applications. Some of the isothiazolinones are difficult to isolate from water due their high polarity. A sensitive and selective analytical method was developed and optimized for the determination of sub-microg/L levels of three isothiazolinones in water samples. Three isothiazolinones are described in this paper: 2-methyl-3-isothiazolinone, 5-chloro-2-methyl-3-isothiazolinone and 4,5-dichloro-2-methyl-3-isothiazolinone. The analytical method involves a robust large-volume direct on-column loop injection of 2 mL on an Aqua ODS HPLC column and tandem MS detection (HPLC-MS/MS). After filtration, samples are directly injected without further pretreatment. Detection limits of the individual target compounds were between 0.03 and 0.1 microg/L employing Multi-Reaction Monitoring (MRM) mass spectrometry. Based on the constant ratio of two selected product-ions together with the retention time, the identification is very selective and quantification is reliable. The method was successfully applied to real samples of membrane flushings, drinking water, surface waters and waste water. Additional investigations showed the instability of the isothiazolinones in river- and waste water. Preservation of river water and waste water samples with sodium azide (NaN(3)) promotes the stability of the isothiazolines in solution. In membrane flushings, waste water, surface waters and drinking water, levels of the three isothiazolinones were all below the limit of detection. In effluents of households containing washings from normal shampoo use, isothiazolinones could be detected.

  16. Graphene oxide as a micro-solid-phase extraction sorbent for the enrichment of parabens from water and vinegar samples.

    PubMed

    Wang, Lu; Zang, Xiaohuan; Wang, Chun; Wang, Zhi

    2014-07-01

    A simple hydrophilic polyamide organic membrane protected micro-solid-phase extraction method with graphene oxide as the sorbent was developed for the enrichment of some parabens from water and vinegar samples prior to gas chromatography with mass spectrometry detection. The main experimental parameters affecting the extraction efficiencies, such as the type and amount of the sorbent, extraction time, stirring rate, salt addition, sample solution pH and desorption conditions, were investigated. Under the optimized experimental conditions, the method showed a good linearity in the range of 0.1-100.0 ng/mL for water samples and 0.5-100.0 ng/mL for vinegar samples, with the correlation coefficients varying from 0.9978 to 0.9997. The limits of detection (S/N = 3) of the method were in the range of 0.005-0.010 ng/mL for water samples and 0.01-0.05 ng/mL for vinegar samples, respectively. The recoveries of the method for the analytes at spiking levels of 5.0 and 70.0 ng/mL were between 84.6 and 106.4% with the relative standard deviations varying from 4.2 to 9.5%. The results indicated that the developed method could be a practical approach for the determination of paraben residues in water and vinegar samples.

  17. Time-weighted average water sampling in Lake Ontario with solid-phase microextraction passive samplers.

    PubMed

    Ouyang, Gangfeng; Zhao, Wennan; Bragg, Leslie; Qin, Zhipei; Alaee, Mehran; Pawliszyn, Janusz

    2007-06-01

    In this study, three types of solid-phase microextraction (SPME) passive samplers, including a fiber-retracted device, a polydimethylsiloxane (PDMS)-rod and a PDMS-membrane, were evaluated to determine the time weighted average (TWA) concentrations of polycyclic aromatic hydrocarbons (PAHs) in Hamilton Harbor (the western tip of Lake Ontario, ON, Canada). Field trials demonstrated that these types of SPME samplers are suitable for the long-term monitoring of organic pollutants in water. These samplers possess all of the advantages of SPME: they are solvent-free, sampling, extraction and concentration are combined into one step, and they can be directly injected into a gas chromatograph (GC) for analysis without further treatment. These samplers also address the additional needs of a passive sampling technique: they are economical, easy to deploy, and the TWA concentrations of target analytes can be obtained with one sampler. Moreover, the mass uptake of these samplers is independent of the face velocity, or the effect can be calibrated, which is desirable for long-term field sampling, especially when the convection conditions of the sampling environment are difficult to measure and calibrate. Among the three types of SPME samplers that were tested, the PDMS-membrane possesses the highest surface-to-volume ratio, which results in the highest sensitivity and mass uptake and the lowest detection level.

  18. Effect of PAC addition on immersed ultrafiltration for the treatment of algal-rich water.

    PubMed

    Zhang, Yan; Tian, Jiayu; Nan, Jun; Gao, ShanShan; Liang, Heng; Wang, Meilian; Li, Guibai

    2011-02-28

    The aim of this study was to evaluate the effect of powdered activated carbon (PAC) addition on the treatment of algal-rich water by immersed ultrafiltration (UF), in terms of permeate quality and membrane fouling. Experiments were performed with a hollow-fiber polyvinyl chloride ultrafiltration membrane at a laboratory scale, 20-25°C and 10 L/(m(2) h) constant permeate flux. UF could achieve an absolute removal of Microcystis aeruginosa cells, but a poor removal of algogenic organic matter (AOM) released into water, contaminants responsible for severe membrane fouling. The addition of 4 g/L PAC to the immersed UF reactor significantly alleviated the development of trans-membrane pressure and enhanced the removal of dissovled organic carbon (by 10.9±1.7%), UV(254) (by 27.1±1.7%), and microcystins (expressed as MC-LR(eq), by 40.8±4.2%). However, PAC had little effect on the rejection of hydrophilic high molecular weight AOM such as carbohydrates and proteins. It was also identified that PAC reduced the concentrations of carbohydrates and proteins in the reactor due to decreased light intensity, as well as the MC-LR(eq) concentration by PAC adsorption.

  19. Water Sample Analysis With the Integrated Virus Detection System

    DTIC Science & Technology

    2010-06-01

    ultrafiltered to reduce and concentrate the volume from 1 L to 1.2 mL. This ultrafiltration (UF) was accomplished in -60 min. The remaining volume was...collected and analyzed with the IVDS. In general, the samples were concentrated with the tangential flow ( ultrafiltration ) filter system before IVDS...Biological Center: Aberdeen Proving Ground, MD, 1999; UNCLASSIFIED Report (AD-A368 535). 2. Wick, C.H.; McCubbin, P.E. Removing Complex Growth Media from MS2

  20. Estimation of uranium and radon concentration in some drinking water samples of Upper Siwaliks, India.

    PubMed

    Singh, Joga; Singh, Harmanjit; Singh, Surinder; Bajwa, B S

    2009-07-01

    Uranium and radon concentration was assessed in water samples taken from hand pumps, natural sources and wells collected from some areas of Upper Siwaliks, Northern India. Fission track registration technique was used to estimate the uranium content of water samples. The uranium concentration in water samples was found to vary from 1.08 +/- 0.03 to 19.68 +/- 0.12 microg l(-1). These values were compared with safe limit values recommended for drinking water. Most of the water samples were found to have uranium concentration below the safe limit of 15 microg l(-1) (WHO, World Health Organization, Guidelines for drinking-water quality (3rd ed.). Geneva, Switzerland: WHO, 2004). The radon estimation in these water samples was made using alpha-scintillometry to study its correlation with uranium. The radon concentration in these samples was found to vary from 0.87 +/- 0.29 to 32.10 +/- 1.79 Bq l(-1). The recorded values of radon concentration were within the recommended safe limit of 4 to 40 Bq l(-1) (UNSCEAR, United Nations Scientific Committee on the Effects of Atomic Radiations, Sources and effects of ionizing radiation. New York: United Nations, 1993). No direct correlation was found between uranium concentration and radon concentration in water samples belonging to Upper Siwaliks. The values of uranium and radon concentration in water were compared with that from the adjoining areas of Punjab state, India.

  1. 40 CFR 257.23 - Ground-water sampling and analysis requirements.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... and analysis requirements. (a) The ground-water monitoring program must include consistent sampling... 40 Protection of Environment 24 2010-07-01 2010-07-01 false Ground-water sampling and analysis requirements. 257.23 Section 257.23 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED)...

  2. UMTRA Project water sampling and analysis plan, Gunnison, Colorado. Revision 2

    SciTech Connect

    1995-09-01

    Surface remedial action at the Gunnison Uranium Mill Tailings Remedial Action Project site began in 1992; completion is expected in 1995. Ground water and surface water will be sampled semiannually at the Gunnison processing site (GUN-01) and disposal site (GUN-08). Results of previous water sampling at the Gunnison processing site indicate that ground water in the alluvium is contaminated by the former uranium processing activities. Background ground water conditions have been established in the uppermost aquifer (Tertiary gravels) at the Gunnison disposal site. Semiannual water sampling is scheduled for the spring and fall. Water quality sampling is conducted at the processing site (1) to ensure protection of human health and the environment, (2) for ground water compliance monitoring during remedial action construction, and (3) to define the extent of contamination. At the processing site, the frequency and duration of sampling will be dependent upon the nature and extent of residual contamination and the compliance strategy chosen. The monitor well locations provide a representative distribution of sampling points to characterize ground water quality and ground water flow conditions in the vicinity of the sites. The list of analytes has been modified with time to reflect constituents that are related to uranium processing activities and the parameters needed for geochemical evaluation.

  3. Automated syringe sampler. [remote sampling of air and water

    NASA Technical Reports Server (NTRS)

    Purgold, G. C. (Inventor)

    1981-01-01

    A number of sampling services are disposed in a rack which slides into a housing. In response to a signal from an antenna, the circutry elements are activated which provide power individually, collectively, or selectively to a servomechanism thereby moving an actuator arm and the attached jawed bracket supporting an evaculated tube towards a stationary needle. One open end of the needle extends through the side wall of a conduit to the interior and the other open end is maintained within the protective sleeve, supported by a bifurcated bracket. A septum in punctured by the end of the needle within the sleeve and a sample of the fluid medium in the conduit flows through the needle and is transferred to a tube. The signal to the servo is then reversed and the actuator arm moves the tube back to its original position permitting the septum to expand and seal the hole made by the needle. The jawed bracket is attached by pivot to the actuator to facilitate tube replacement.

  4. H02 WETLAND TREATMENT SYSTEM WATER CHEMISTRY SAMPLING AND RESULTS REPORT

    SciTech Connect

    Bach, M; Michael Serrato, M; Eric Nelson, E

    2008-02-15

    inorganic chemistry influence on pH. In addition, alternative methods to alleviate or mitigate the pH increase were evaluated. This study documents the results of sampling activities undertaken and conveys the analytical results along with suggestions for operation of the H-02 Wetland Treatment System. The water samples collected and the water quality data generated from this activity are for analytical purposes only, and as such, were not collected in support of compliance activities.

  5. Towards a phylogenetic generic classification of Thelypteridaceae: Additional sampling suggests alterations of neotropical taxa and further study of paleotropical genera.

    PubMed

    Almeida, Thaís Elias; Hennequin, Sabine; Schneider, Harald; Smith, Alan R; Batista, João Aguiar Nogueira; Ramalho, Aline Joseph; Proite, Karina; Salino, Alexandre

    2016-01-01

    Thelypteridaceae is one of the largest fern families, having about 950 species and a cosmopolitan distribution but with most species occurring in tropical and subtropical regions. Its generic classification remains controversial, with different authors recognizing from one up to 32 genera. Phylogenetic relationships within the family have not been exhaustively studied, but previous studies have confirmed the monophyly of the lineage. Thus far, sampling has been inadequate for establishing a robust hypothesis of infrafamilial relationships within the family. In order to understand phylogenetic relationships within Thelypteridaceae and thus to improve generic reclassification, we expand the molecular sampling, including new samples of Old World taxa and, especially, many additional neotropical representatives. We also explore the monophyly of exclusively or mostly neotropical genera Amauropelta, Goniopteris, Meniscium, and Steiropteris. Our sampling includes 68 taxa and 134 newly generated sequences from two plastid genomic regions (rps4-trnS and trnL-trnF), plus 73 rps4 and 72 trnL-trnF sequences from GenBank. These data resulted in a concatenated matrix of 1980 molecular characters for 149 taxa. The combined data set was analyzed using maximum parsimony and bayesian inference of phylogeny. Our results are consistent with the general topological structure found in previous studies, including two main lineages within the family: phegopteroid and thelypteroid. The thelypteroid lineage comprises two clades; one of these included the segregates Metathelypteris, Coryphopteris, and Amauropelta (including part of Parathelypteris), whereas the other comprises all segregates of Cyclosorus s.l., such as Goniopteris, Meniscium, and Steiropteris (including Thelypteris polypodioides, previously incertae sedis). The three mainly neotropical segregates were found to be monophyletic but nested in a broadly defined Cyclosorus. The fourth mainly neotropical segregate, Amauropelta

  6. USE OF NATURAL WATERS AS U. S. GEOLOGICAL SURVEY REFERENCE SAMPLES.

    USGS Publications Warehouse

    Janzer, Victor J.

    1985-01-01

    The U. S. Geological Survey conducts research and collects hydrologic data relating to the Nation's water resources. Seven types of natural matrix reference water samples are prepared for use in the Survey's quality assurance program. These include samples containing major constituents, trace metals, nutrients, herbicides, insecticides, trace metals in a water and suspended-sediment mixture, and precipitation (snowmelt). To prepare these reference samples, natural water is collected in plastic drums and the sediment is allowed to settle. The water is then filtered, selected constituents are added, and if necessary the water is acidified and sterilized by ultraviolet irradiation before bottling in plastic or glass. These reference samples are distributed twice yearly to more than 100 laboratories for chemical analysis. The most probable values for each constituent are determined by evaluating the data submitted by the laboratories using statistical techniques recommended by ASTM.

  7. UMTRA Project water sampling and analysis plan, Durango, Colorado. Revision 1

    SciTech Connect

    1995-09-01

    Planned, routine ground water sampling activities at the US Department of Energy (DOE) Uranium Mill Tailings Remedial Action (UMTRA) Project site in Durango, Colorado, are described in this water sampling and analysis plan. The plan identifies and justifies the sampling locations, analytical parameters, detection limits, and sampling frequency for the routine monitoring stations at the site. The ground water data are used to characterize the site ground water compliance strategies and to monitor contaminants of potential concern identified in the baseline risk assessment (DOE, 1995a). Regulatory basis for routine ground water monitoring at UMTRA Project sites is derived from the US EPA regulations in 40 CFR Part 192 (1994) and EPA standards of 1995 (60 FR 2854). Sampling procedures are guided by the UMTRA Project standard operating procedures (SOP) (JEG, n.d.), the Technical Approach Document (TAD) (DOE, 1989), and the most effective technical approach for the site.

  8. Considerations for sampling inorganic constituents in ground water using diffusion samplers

    USGS Publications Warehouse

    Vroblesky, D.A.; Petkewich, M.D.; Campbell, T.R.; ,

    2002-01-01

    Data indicate that nylon-screen and dialysis diffusion samplers are capable of obtaining concentrations of inorganic solutes in ground water from wells that closely correspond to concentrations obtained by low-flow sampling. Conservative solutes, such as chloride, can be sampled by filling the diffusion samplers with oxygenated water. The samplers should be filled with anaerobic water for sampling redoxsensitive solutes. Oxidation of iron within the samplers, either by using aerobic fill water or by in-well oxygenation events, can lead to erroneous iron concentrations. Lithologic and chemical heterogeneity and sampler placement depth can lead to differences between concentrations from diffusion samples and low-flow samples because of mixing during pumping. A disadvantage of regenerated cellulose dialysis samplers is that they can begin to biodegrade within the two weeks of deployment. Nylon-screen samplers buried beneath streambed sediment along the unnamed tributary in a discharge zone of arseniccontaminated ground water were useful in locating the specific discharge zone.

  9. Additions of nutrients and major ions by the atmosphere and tributaries to nearshore waters of northwestern Lake Huron

    USGS Publications Warehouse

    Manny, Bruce A.; Owens, R.W.

    1983-01-01

    Nutrient additions by the atmosphere and six tributaries to nearshore waters of northwestern Lake Huron were measured at weekly intervals from August 1975 to July 1976. The atmosphere contributed 43% of the nitrogen (N) and 10% of the phosphorus (P) that was added during the year. The 1975–76 atmospheric loading rate of total N to this area (11 kg/ha/yr) was one of the highest found to date in the United States. N was conserved more efficiently than P in the tributary drainage basins. Of the N and P that fell annually on the watersheds under study, 2 to 37% of the N and 31 to 84% of the P was carried with runoff to the lake. From a basin where ditching and clear-cutting occurred, water, P, silica (SiO2), N, and sodium were lost at higher rates than from five other basins. Most of the N in bulk atmospheric samples (23%) and tributary waters (56%) was dissolved organic N, a form of N not often measured.

  10. Filtration of water-sediment samples for the determination of organic compounds

    USGS Publications Warehouse

    Sandstrom, Mark W.

    1995-01-01

    This report describes the equipment and procedures used for on-site filtration of surface-water and ground-water samples for determination of organic compounds. Glass-fiber filters and a positive displacement pumping system are suitable for processing most samples for organic analyses. An optional system that uses disposable in-line membrane filters is suitable for a specific gas chromatography/mass spectrometry, selected-ion monitoring analytical method for determination of organonitrogen herbicides. General procedures to minimize contamination of the samples include preparing a clean workspace at the site, selecting appropriate sample-collection materials, and cleaning of the equipment with detergent, tap water, and methanol.

  11. Heat transfer characteristics for some coolant additives used for water cooled engines

    SciTech Connect

    Abou-Ziyan, H.Z.; Helali, A.H.B.

    1996-12-31

    Engine coolants contain certain additives to prevent engine overheating or coolant freezing in cold environments. Coolants, also, contain corrosion and rust inhibitors, among other additives. As most engines are using engine cooling solutions, it is of interest to evaluate the effect of engine coolants on the boiling heat transfer coefficient. This has its direct impact on radiator size and environment. This paper describes the apparatus and the measurement techniques. Also, it presents the obtained boiling heat transfer results at different parameters. Three types of engine coolants and their mixtures in distilled water are evaluated, under sub-cooled and saturated boiling conditions. A profound effect of the presence of additives in the coolant, on heat transfer, was clear since changes of heat transfer for different coolants were likely to occur. The results showed that up to 180% improvement of boiling heat transfer coefficient is experienced with some types of coolants. However, at certain concentrations other coolants provide deterioration or not enhancement in the boiling heat transfer characteristics. This investigation proved that there are limitations, which are to be taken into consideration, for the composition of engine coolants in different environments. In warm climates, ethylene glycol should be kept at the minimum concentration required for dissolving other components, whereas borax is beneficial to the enhancement of the heat transfer characteristics.

  12. Stabilized liquid membrane device (SLMD) for the passive, integrative sampling of labile metals in water

    USGS Publications Warehouse

    Brumbaugh, W.G.; Petty, J.D.; Huckins, J.N.; Manahan, S.E.

    2002-01-01

    A stabilized liquid membrane device (SLMD) is described for potential use as an in situ, passive, integrative sampler for cadmium (Cd), cobalt (Co), copper (Cu), nickel (Ni), lead (Pb), and zinc (Zn) in natural waters. The SLMD (patent pending) consists of a 2.5-cm-wide by 15-cm-long strip of low-density polyethylene (LDPE) layflat tubing containing 1 mL of an equal mixture (v/v) of oleic acid (cis-9-octadecenoic acid) and EMO-8Q (7-[4-ethyl-1-methyloctyl]-8-quinolinol). The reagent mixture continuously diffuses to the exterior surface of the LDPE membrane, and provides for sequestration of several divalent metals for up to several weeks. Depending on sampler configuration, concentration factors of several thousand can be realized for these metal ions after just a few days. In addition to in situ deployment, the SLMD may be useful for laboratory determination of labile metal species in grab samples. Methods for minimizing the effects of water flow on the sampling rate are currently under investigation.

  13. Molecularly imprinted polymers: an analytical tool for the determination of benzimidazole compounds in water samples.

    PubMed

    Cacho, Carmen; Turiel, Esther; Pérez-Conde, Concepción

    2009-05-15

    Molecularly imprinted polymers (MIPs) for benzimidazole compounds have been synthesized by precipitation polymerization using thiabendazole (TBZ) as template, methacrylic acid as functional monomer, ethyleneglycol dimethacrylate (EDMA) and divinylbenzene (DVB) as cross-linkers and a mixture of acetonitrile and toluene as porogen. The experiments carried out by molecularly imprinted solid phase extraction (MISPE) in cartridges demonstrated the imprint effect in both imprinted polymers. MIP-DVB enabled a much higher breakthrough volume than MIP-EDMA, and thus was selected for further experiments. The ability of this MIP for the selective recognition of other benzimidazole compounds (albendazole, benomyl, carbendazim, fenbendazole, flubendazole and fuberidazole) was evaluated. The obtained results revealed the high selectivity of the imprinted polymer towards all the selected benzimidazole compounds. An off-line analytical methodology based on a MISPE procedure has been developed for the determination of benzimidazole compounds in tap, river and well water samples at concentration levels below the legislated maximum concentration levels (MCLs) with quantitative recoveries. Additionally, an on-line preconcentration procedure based on the use of a molecularly imprinted polymer as selective stationary phase in HPLC is proposed as a fast screening method for the evaluation of the presence of benzimidazole compounds in water samples.

  14. Determination of four heterocyclic insecticides by ionic liquid dispersive liquid-liquid microextraction in water samples.

    PubMed

    Liu, Yu; Zhao, Ercheng; Zhu, Wentao; Gao, Haixiang; Zhou, Zhiqiang

    2009-02-06

    A novel microextraction method termed ionic liquid dispersive liquid-liquid microextraction (IL-DLLME) combining high-performance liquid chromatography with diode array detection (HPLC-DAD) was developed for the determination of insecticides in water samples. Four heterocyclic insecticides (fipronil, chlorfenapyr, buprofezin, and hexythiazox) were selected as the model compounds for validating this new method. This technique combines extraction and concentration of the analytes into one step, and the ionic liquid was used instead of a volatile organic solvent as the extraction solvent. Several important parameters influencing the IL-DLLME extraction efficiency such as the volume of extraction solvent, the type and volume of disperser solvent, extraction time, centrifugation time, salt effect as well as acid addition were investigated. Under the optimized conditions, good enrichment factors (209-276) and accepted recoveries (79-110%) were obtained for the extraction of the target analytes in water samples. The calibration curves were linear with correlation coefficient ranged from 0.9947 to 0.9973 in the concentration level of 2-100 microg/L, and the relative standard deviations (RSDs, n=5) were 4.5-10.7%. The limits of detection for the four insecticides were 0.53-1.28 microg/L at a signal-to-noise ratio (S/N) of 3.

  15. Procedures for Handling and Chemical Analysis of Sediment and Water Samples,

    DTIC Science & Technology

    1981-05-01

    8217 poe oh wou(.,ldy Arobably n d equlirte anr mixingr ,! I t- 10Percent of the total samUple load. It is a ,ii- robin -sample alyistudies. Add itioa...established to prevent undue sample contamination as a consequence of the previous sampling effort. Surface water samples should receive the highest priority ...anhydrous sodium sulfate column containing 20 g of the desiccant. Collect the sample in a round -bottomed flask. Rinse the column with 25 ml methylene

  16. Evaluation of the Snap Sampler for Sampling Ground Water Monitoring Wells for VOCs and Explosives

    DTIC Science & Technology

    2007-08-01

    ER D C/ CR R EL T R -0 7 -1 4 Evaluation of the Snap Sampler for Sampling Ground Water Monitoring Wells for VOCs and Explosives Louise...release; distribution is unlimited. ERDC/CRREL TR-07-14 August 2007 Evaluation of the Snap Sampler for Sampling Ground Water Monitoring...determine the ability of the Snap Sampler to recover representative concentrations of VOC and explosives in ground water . For the laboratory studies

  17. Development of a benthic-flux chamber for measurement of ground-water seepage and water sampling for mercury analysis at the sediment-water interface

    USGS Publications Warehouse

    Menheer, M.A.

    2004-01-01

    A benthic-flux chamber was constructed to collect data to determine the relation between ground- and surface-water interaction and mercury concentrations in water at the sediment- water interface. The benthic-flux chamber was successfully used to measure the rate of ground water seeping to surface water or surface water seeping to ground water, and to collect water samples for mercury analysis from the sedimentwater interface in a lake setting. The benthic-flux chamber was designed to be deployed in relatively calm fresh water lakes, in areas of water less than 2 meters deep. The groundwater seepage rate data were comparable to data from an in-line flow meter in a calibration tank and with data from two 55-gallon drum seepage meters concurrently deployed in two different lakes. The benthic-flux chamber was used to collect possible water samples for analysis of total mercury and methylmercury concentrations.

  18. Detection and genetic characterization of norovirus in environmental water samples in Thailand.

    PubMed

    Kittigul, Leera; Panjangampatthana, Apinya; Pombubpa, Kannika; Taweekate, Yuthana; Pungchitton, Supornwit; Diraphat, Pornphan; Siripanichgon, Kanokrat

    2012-03-01

    The aim of this study was to detect and characterize noroviruses (NoVs) in environmental water samples. One hundred and fourteen water samples were collected from a river and irrigation canals in central Thailand during 2006-2007. NoVs were detected by RT-nested PCR in 13% of the samples. The river samples (22%) contained NoVs at a higher frequency than the irrigation canal samples (4%). Among the 15 NoV-positive samples, 9 harbored genogroup (G) I, 2 samples with GII, and 4 samples with mixed GI and GII. DNA sequencing of PCR amplicons and phylogenetic analysis of partial capsid gene revealed that 5 samples were of genotype GI-2, 1 sample was GI-6, and 1 sample was a mix of GI-2 and GII-unclassified genotypes. NoVs in water samples quantified using quantitative RT-PCR were in the range of 4.91 x 10(2) -1.26 x 10(3) copies/ml for NoV GI and 3.51 x 10(3) copies/ml for NoV GII. This is the first study demonstrating the presence of NoV variants in water samples collected from a river and the adjacent canals of Thailand.

  19. An instrument for collecting discrete large-volume water samples suitable for ecological studies of microorganisms

    NASA Astrophysics Data System (ADS)

    Wommack, K. Eric; Williamson, Shannon J.; Sundbergh, Arthur; Helton, Rebekah R.; Glazer, Brian T.; Portune, Kevin; Craig Cary, S.

    2004-11-01

    Microbiological investigations utilizing molecular genetic approaches to characterize microbial communities can require large volume water samples, tens to hundreds of liters. The requirement for large volume samples can be especially challenging in deep-sea hydrothermal vent environments of the oceanic ridge system. By and large studies of these environments rely on deep submergence vehicles. However collection of large volume (>100 L) water samples adjacent to the benthos is not feasible due to weight considerations. To address the technical difficulty of collecting large volume water samples from hydrothermal diffuse flow environments, a semi-autonomous large-volume water sampler (LVWS) was designed. The LVWS is capable of reliably collecting and bringing to the surface 120 L water samples from diffuse flow environments. Microscopy, molecular genetic and chemical analyses of water samples taken from 9°N East Pacific Rise are shown to demonstrate the utility of the LVWS for studies of near-benthos environments. To our knowledge this is the first report of virioplankton abundance within diffuse-flow waters of a deep-sea hydrothermal vent environment. Because of its simple design and relatively low cost, the LVWS should be applicable to a variety of studies which require large-volume water samples collected immediately adjacent to the benthos.

  20. Assessment of PDMS-water partition coefficients: implications for passive environmental sampling of hydrophobic organic compounds

    USGS Publications Warehouse

    DiFilippo, Erica L.; Eganhouse, Robert P.

    2010-01-01

    Solid-phase microextraction (SPME) has shown potential as an in situ passive-sampling technique in aquatic environments. The reliability of this method depends upon accurate determination of the partition coefficient between the fiber coating and water (Kf). For some hydrophobic organic compounds (HOCs), Kf values spanning 4 orders of magnitude have been reported for polydimethylsiloxane (PDMS) and water. However, 24% of the published data examined in this review did not pass the criterion for negligible depletion, resulting in questionable Kf values. The range in reported Kf is reduced to just over 2 orders of magnitude for some polychlorinated biphenyls (PCBs) when these questionable values are removed. Other factors that could account for the range in reported Kf, such as fiber-coating thickness and fiber manufacturer, were evaluated and found to be insignificant. In addition to accurate measurement of Kf, an understanding of the impact of environmental variables, such as temperature and ionic strength, on partitioning is essential for application of laboratory-measured Kf values to field samples. To date, few studies have measured Kf for HOCs at conditions other than at 20 degrees or 25 degrees C in distilled water. The available data indicate measurable variations in Kf at different temperatures and different ionic strengths. Therefore, if the appropriate environmental variables are not taken into account, significant error will be introduced into calculated aqueous concentrations using this passive sampling technique. A multiparameter linear solvation energy relationship (LSER) was developed to estimate log Kf in distilled water at 25 degrees C based on published physicochemical parameters. This method provided a good correlation (R2 = 0.94) between measured and predicted log Kf values for several compound classes. Thus, an LSER approach may offer a reliable means of predicting log Kf for HOCs whose experimental log Kf values are presently unavailable. Future

  1. Physicochemical Characterization of Lake Spray Aerosol Generated from Great Lakes Water Samples

    NASA Astrophysics Data System (ADS)

    Ault, A. P.; Axson, J. L.; May, N.; Pratt, K.

    2014-12-01

    Wave breaking across bodies of water releases particles into the air which can impact climate and human health. Similar to sea spray aerosols formed through marine wave breaking, freshwater lakes generate lake spray aerosol (LSA). LSA can impact climate directly through scattering/absorption and indirectly through cloud nucleation. In addition, these LSA are suggested to impact human health through inhalation of these particles during algal bloom periods characterized by toxic cyanobacteria. Few studies have been conducted to assess the physical and chemical properties of freshwater LSA. Herein, we discuss constructing a LSA generation system and preliminary physical and chemical characterization of aerosol generated from water samples collected at various sites across Lake Erie, Lake Huron, Lake Superior, and Lake Michigan. Information on aerosol size distributions, number concentrations, and chemical composition will be discussed as a function of lake water blue-green algae concentration, dissolved organic carbon concentration, temperature, conductivity, and dissolved oxygen concentration. These studies represent a first step towards evaluating the potential for LSA to impact climate and health in the Great Lakes region.

  2. Data Validation Package, April and June 2016 Groundwater and Surface Water Sampling at the Gunnison, Colorado, Processing Site, October 2016

    SciTech Connect

    Linard, Joshua; Campbell, Sam

    2016-10-01

    This event included annual sampling of groundwater and surface water locations at the Gunnison, Colorado, Processing Site. Sampling and analyses were conducted as specified in Sampling and Analysis Plan for US Department of Energy Office of Legacy Management Sites (LMS/PRO/S04351, continually updated, http://energy.gov/lm/downloads/sampling-and­ analysis-plan-us-department-energy-office-legacy-management-sites). Samples were collected from 28 monitoring wells, three domestic wells, and six surface locations in April at the processing site as specified in the draft 2010 Ground Water Compliance Action Plan for the Gunnison, Colorado, Processing Site. Planned monitoring locations are shown in Attachment 1, Sampling and Analysis Work Order. Domestic wells 0476 and 0477 were sampled in June because the homes were unoccupied in April, and the wells were not in use. Duplicate samples were collected from locations 0126, 0477, and 0780. One equipment blank was collected during this sampling event. Water levels were measured at all monitoring wells that were sampled. See Attachment 2, Trip Reports for additional details. The analytical data and associated qualifiers can be viewed in environmental database reports and are also available for viewing with dynamic mapping via the GEMS (Geospatial Environmental Mapping System) website at http://gems.lm.doe.gov/#. No issues were identified during the data validation process that requires additional action or follow-up. An assessment of anomalous data is included in Attachment 3. Interpretation and presentation of results, including an assessment ofthe natural flushing compliance strategy, will be reported in the upcoming 2016 Verification Monitoring Report. U.S.

  3. Non-additive response of blends of rice and potato starch during heating at intermediate water contents: A differential scanning calorimetry and proton nuclear magnetic resonance study.

    PubMed

    Bosmans, Geertrui M; Pareyt, Bram; Delcour, Jan A

    2016-02-01

    The impact of different hydration levels, on gelatinization of potato starch (PS), rice starch (RS) and a 1:1 blend thereof, was investigated by differential scanning calorimetry and related to nuclear magnetic resonance proton distributions of hydrated samples, before and after heating. At 20% or 30% hydration, the visual appearance of all samples was that of a wet powder, and limited, if any, gelatinization occurred upon heating. At 30% hydration, changes in proton distributions were observed and related to plasticization of amorphous regions in the granules. At 50% hydration, the PS-RS blend appeared more liquid-like than other hydrated samples and showed more pronounced gelatinization than expected based on additive behavior of pure starches. This was due to an additional mobile water fraction in the unheated PS-RS blend, originating from differences in water distribution due to altered stacking of granules and/or altered hydration of PS due to presence of cations in RS.

  4. Change Of Electrical Resistivity Depending On Water Saturation Of The Concrete Samples

    NASA Astrophysics Data System (ADS)

    Sabbaǧ, Nevbahar; Uyanık, Osman

    2016-04-01

    In this study, the changes of electrical apparent resistivity values depending on the water saturation of cubic concrete samples which designed according to different strength were investigated. For this purpose, 3 different concrete design as poor, middle and good strength 150x150x150mm dimensions 9 for each design cubic samples were prepared. After measuring the weight of the prepared samples, in oven were dried at 105 ° C for 24 hours and then the dry weights were measured. Then the samples were placed into the curing pool and saturated weight of the samples were measured in specific time periods during the 90 day take out from the curing pool and the water content were calculated at each stage of these processes. The water content of the samples were obtained during 90 days specific points in time and as well as electrical apparent resistivity method of the different surfaces of the samples the potential difference measurements made by electrical resistivity method and electrical apparent resistivity values of the samples were calculated. Depending on time obtained from this study with respect to time curves of the water content and the apparent resistivity values were constructed. Results showed that the electrical apparent resistivity values increased depends on the water content. This study was supported with OYP05277-DR-14 Project No. by SDU and State Hydraulic Works 13th Regional/2012-01 Project No. Keywords: Concrete, cubic sample, Resistivity, water content, time

  5. Screening of ground water samples for volatile organic compounds using a portable gas chromatograph

    USGS Publications Warehouse

    Buchmiller, R.C.

    1989-01-01

    A portable gas chromatograph was used to screen 32 ground water samples for volatile organic compounds. Seven screened samples were positive; four of the seven samples had volatile organic substances identified by second-column confirmation. Four of the seven positive, screened samples also tested positive in laboratory analyses of duplicate samples. No volatile organic compounds were detected in laboratory analyses of samples that headspace screening indicated to be negative. Samples that contained volatile organic compounds, as identified by laboratory analysis, and that contained a volatile organic compound present in a standard of selected compounds were correctly identified by using the portable gas chromatography. Comparisons of screened-sample data with laboratory data indicate the ability to detect selected volatile organic compounds at concentrations of about 1 microgram per liter in the headspace of water samples by use of a portable gas chromatography. -Author

  6. Comparison of the mutagenic activity of XAD4 and blue rayon extracts of surface water and related drinking water samples.

    PubMed

    Kummrow, Fábio; Rech, Celia M; Coimbrão, Carlos A; Roubicek, Deborah A; Umbuzeiro, Gisela de A

    2003-11-10

    The combination of mutagenicity tests and selective extraction methodologies can be useful to indicate the possible classes of genotoxic organic contaminants in water samples. Treated and source water samples from two sites were analyzed: a river under the influence of an azo dye-processing plant discharge and a reservoir not directly impacted with industrial discharges, but contaminated with untreated domestic sewage. Organic extraction was performed in columns packed with XAD4 resin, that adsorbs a broad class of mutagenic compounds like polycyclic aromatic hydrocarbons (PAHs), arylamines, nitrocompounds, quinolines, antraquinones, etc., including the halogenated disinfection by-products; and with blue rayon that selectively adsorbs polycyclic planar structures. The organic extracts were tested for mutagenicity with the Salmonella assay using TA98 and TA100 strains and the potencies were compared. A protocol for cleaning the blue rayon fibers was developed and the efficiency of the reused fibers was analyzed with spiked samples. For the river water samples under the influence of the azo-type dye-processing plant, the mutagenicity was much higher for both blue rayon and XAD4 extracts when compared to the water from the reservoir not directly impacted with industrial discharges. For the drinking water samples, although both sites showed mutagenic responses with XAD4, only samples from the site under the influence of the industrial discharge showed mutagenic activity with the blue rayon extraction, suggesting the presence of polycyclic compounds in those samples. As expected, negative results were found with the blue rayon extracts of the drinking water collected from the reservoir not contaminated with industrial discharges. In this case, it appears that using the blue rayon to extract drinking water samples and comparing the results with the XAD resin extracts we were able to distinguish the mutagenicity caused by industrial contaminants from the halogenated

  7. Facile synthesis of SrCO3 nanostructures in methanol/water solution without additives

    PubMed Central

    2012-01-01

    Highly dispersive strontium carbonate (SrCO3) nanostructures with uniform dumbbell, ellipsoid, and rod-like morphologies were synthesized in methanol solution without any additives. These SrCO3 were characterized by X-ray diffraction, field emission scanning electron microscopy, and N2 adsorption-desorption. The results showed that the reaction temperature and the methanol/water ratio had important effects on the morphologies of SrCO3 particles. The dumbbell-like SrCO3 exhibited a Broader-Emmett-Teller surface area of 14.9 m2 g−1 and an average pore size of about 32 nm with narrow pore size distribution. The formation mechanism of the SrCO3 crystal was preliminary presented. PMID:22704526

  8. The effects of water sample treatment, preparation, and storage prior to cyanotoxin analysis for cylindrospermopsin, microcystin and saxitoxin.

    PubMed

    Kamp, Lisa; Church, Jennifer L; Carpino, Justin; Faltin-Mara, Erin; Rubio, Fernando

    2016-02-25

    Cyanobacterial harmful algal blooms occur in freshwater lakes, ponds, rivers, and reservoirs, and in brackish waters throughout the world. The wide variety of cyanotoxins and their congeners can lead to frequent exposure of humans through consumption of meat, fish, seafood, blue-green algal products and water, accidental ingestion of contaminated water and cyanobacterial scum during recreational activities, and inhalation of cyanobacterial aerosols. Cyanotoxins can also occur in the drinking water supply. In order to monitor human exposure, sensitive analytical methods such as enzyme linked immunosorbent assay and liquid chromatography-mass spectrometry are often used. Regardless of the analytical method of choice, some problems regularly occur during sample collection, treatment, storage, and preparation which cause toxin loss and therefore underestimation of the true concentration. To evaluate the potential influence of sample treatment, storage and preparation materials on surface and drinking water samples, the effects of different types of materials on toxin recovery were compared. Collection and storage materials included glass and various types of plastics. It was found that microcystin congeners LA and LF adsorbed to polystyrene, polypropylene, high density polyethylene and polycarbonate storage containers, leading to low recoveries (<70%), cylindrospermopsin and saxitoxin did not adsorb to the containers tested. Therefore, this study shows that glass or polyethylene terephthalate glycol containers are the materials of choice for collection and storage of samples containing the cyanotoxins cylindrospermopsin, microcystins, and saxitoxin. This study also demonstrated that after 15 min chlorine decreased the concentration of microcystin LR to <40%, microcystin LA and saxitoxin to <15%, therefore quenching of drinking water samples immediately upon sample collection is critical for accurate analysis. In addition, the effect of various drinking water treatment

  9. Polymer Growth Rate in a Wire Chamber with Oxygen,Water, or Alcohol Gas Additives

    SciTech Connect

    Boyarski, Adam; /SLAC

    2008-07-02

    The rate of polymer growth on wires was measured in a wire chamber while the chamber was aged initially with helium-isobutane (80:20) gas, and then with either oxygen, water, or alcohol added to the gas. At the completion of the aging process for each gas mixture, the carbon content on the wires was measured in a SEM/EDX instrument. The same physical wires were used in all the gas mixtures, allowing measurement of polymer build up or polymer depletion by each gas additive. It is found that the rate of polymer growth is not changed by the presence of oxygen, water or alcohol. Conjecture that oxygen reduces breakdown by removing polymer deposits on field wires is negated by these measurements. Instead, it appears that the reduced breakdown is due to lower resistance in the polymer from oxygen ions being transported into the polymer. It is also observed that field wires bombarded by the electrons in the SEM and then placed back into the chamber show an abundance of single electrons being emitted, indicating that electron charge is stored in the polymer layer and that a high electric field is necessary to remove the charge.

  10. Separating Octadecyltrimethoxysilane Hydrolysis and Condensation at the Air/Water Interface through Addition of Methyl Stearate

    PubMed Central

    Britt, David W.; Hlady, Vladimir

    2012-01-01

    The hydrolysis and condensation of octadecyltrimethoxysilane (OTMS) at the air/water interface were monitored through molecular area changes at a constant surface pressure of 10 mN/m. The onset of condensation was delayed through the addition of methyl stearate (SME) acting as an inert filler molecule. In the absence of SME, complete gelation of OTMS required 30 h, during which time OTMS condensation occurred concomitantly with hydrolysis. In the presence of SME, the OTMS monolayer gelation rate increased in proportion to the amount of SME present. A 1:6 OTMS:SME molar ratio resulted in monolayer gelation within 30 min, suggesting completion of monomer hydrolysis prior to condensation. These findings indicate that lability of OTMS to hydrolysis at the air/water interface is governed by steric and conformational constraints at the silicon atom site, with monomeric OTMS being much more reactive than oligomeric OTMS. Fluorescence microscope images demonstrated that the OTMS condensed domain size also decreased with increasing SME concentrations, further implicating SME’s role as an inert filler. PMID:25132807

  11. Vigorous Mold Growth in Soils After Addition of Water-Insoluble Fatty Substances

    PubMed Central

    Krause, Frank P.; Lange, Willy

    1965-01-01

    Various water-insoluble fatty compounds, when added to soil in finely divided form, will support as high-caloric nutrients a visible, vigorous growth of the molds, Fusarium solani Mart., F. diversisporum Sherb., and F. equiseti. n-Paraffins and olefins are most effective, because the effect of additives is reduced to the extent that oxygen atoms are introduced into the molecule. n-Fatty alcohols support growth in soil almost as well as the paraffins; however, growth is reduced when branched-chain compounds are added as nutrients. Compounds that will support mold growth when added to air-dried soil as finely powdered solids will not do so when incorporated at temperatures above their melting point, but will produce dense growth when applied to wet soil in this form. Mold growth is correlated with degradation of fatty matter. The rate of degradation is controlled by the availability of water, oxygen, and the basic inorganic nutrients. Images Fig. 1 Fig. 2 PMID:14325872

  12. Occurrence of microbial indicators and Clostridium perfringens in wastewater, water column samples, sediments, drinking water, and Weddell seal feces collected at McMurdo Station, Antarctica.

    PubMed

    Lisle, John T; Smith, James J; Edwards, Diane D; McFeters, Gordon A

    2004-12-01

    McMurdo Station, Antarctica, has discharged untreated sewage into McMurdo Sound for decades. Previous studies delineated the impacted area, which included the drinking water intake, by using total coliform and Clostridium perfringens concentrations. The estimation of risk to humans in contact with the impacted and potable waters may be greater than presumed, as these microbial indicators may not be the most appropriate for this environment. To address these concerns, concentrations of these and additional indicators (fecal coliforms, Escherichia coli, enterococci, coliphage, and enteroviruses) in the untreated wastewater, water column, and sediments of the impacted area and drinking water treatment facility and distribution system at McMurdo Station were determined. Fecal samples from Weddell seals in this area were also collected and analyzed for indicators. All drinking water samples were negative for indicators except for a single total coliform-positive sample. Total coliforms were present in water column samples at higher concentrations than other indicators. Fecal coliform and enterococcus concentrations were similar to each other and greater than those of other indicators in sediment samples closer to the discharge site. C. perfringens concentrations were higher in sediments at greater distances from the discharge site. Seal fecal samples contained concentrations of fecal coliforms, E. coli, enterococci, and C. perfringens similar to those found in untreated sewage. All samples were negative for enteroviruses. A wastewater treatment facility at McMurdo Station has started operation, and these data provide a baseline data set for monitoring the recovery of the impacted area. The contribution of seal feces to indicator concentrations in this area should be considered.

  13. Occurrence of microbial indicators and Clostridium perfringens in wastewater, water column samples, sediments, drinking water, and Weddell seal feces collected at McMurdo Station, Antarctica

    USGS Publications Warehouse

    Lisle, J.T.; Smith, J.J.; Edwards, D.D.; McFeters, G.A.

    2004-01-01

    McMurdo Station, Antarctica, has discharged untreated sewage into McMurdo Sound for decades. Previous studies delineated the impacted area, which included the drinking water intake, by using total coliform and Clostridium perfringens concentrations. The estimation of risk to humans in contact with the impacted and potable waters may be greater than presumed, as these microbial indicators may not be the most appropriate for this environment. To address these concerns, concentrations of these and additional indicators (fecal coliforms, Escherichia coli, enterococci, coliphage, and enteroviruses) in the untreated wastewater, water column, and sediments of the impacted area and drinking water treatment facility and distribution system at McMurdo Station were determined. Fecal samples from Weddell seals in this area were also collected and analyzed for indicators. All drinking water samples were negative for indicators except for a single total coliform-positive sample. Total coliforms were present in water column samples at higher concentrations than other indicators. Fecal coliform and enterococcus concentrations were similar to each other and greater than those of other indicators in sediment samples closer to the discharge site. C. perfringens concentrations were higher in sediments at greater distances from the discharge site. Seal fecal samples contained concentrations of fecal coliforms, E. coli, enterococci, and C. perfringens similar to those found in untreated sewage. All samples were negative for enteroviruses. A wastewater treatment facility at McMurdo Station has started operation, and these data provide a baseline data set for monitoring the recovery of the impacted area. The contribution of seal feces to indicator concentrations in this area should be considered.

  14. [Distribution of Phosphorus Forms in the Overlying Water Under Disturbance with the Addition of Algae].

    PubMed

    Chen, Jun; Li, Yong; Li, Da-peng; Huang, Yong; Zhu, Pei-ying

    2016-04-15

    Distribution of different phosphorus (P) forms in the overlying water and the contribution of different algae to the P disappearance were investigated under disturbance with the addition of algae (Microcystis aeruginosa and Selenastrum capricornutum, respectively). The sediments and overlying water were taken from Meiliang Bay in Taihu Lake. The results showed that the concentrations of total P (TP), dissolved total P (DTP), dissolved inorganic P (DIP) and biavailable P (BAP) decreased with and without disturbance. The uptake of DTP and DIP by Microcystis aeruginosa was better than that of Selenastrum capricornutum under the disturbance, but it was the opposite without the disturbance. The disappearance of P in the overlying water was attributed completely to the physico-chemical adsorption of the suspended solids and the uptake of algae. But the contribution of suspended solids and algae depended on the disturbance. The contribution of Microcystis aeruginosa and Selenastrum capricornutum to DTP and DIP absorption was about 60% without disturbance. However, the value was reduced to 40% (Microcystis aeruginosa) and 25% ( Selenastrum capricornutum) under the disturbance. Under the disturbance and the action of algae, the distribution of sedimentary P forms changed. NH4 Cl-P and Ca-P release and Fe/Al-P increase were observed with and without disturbance. The decrease of NH4 Cl-P and Ca-P and the increase of Fe/Al-P were more obvious with disturbance than without disturbance. Selenastrum capricornutum was favor of the release of Ca-P and the formation of Fe/Al-P.

  15. Prevalence of rotavirus, adenovirus, hepatitis A virus and enterovirus in water samples collected from different region of Peshawar, Pakistan.

    PubMed

    Ahmad, Tahir; Arshad, Najma; Adnan, Fazal; Sadaf Zaidi, Najam-Us-Sahar; Shahid, Muhammad Talha; Zahoor, Usman; Afzal, Muhammad S; Anjum, Sadia

    2016-12-23

    Viral gastroenteritis and other water-borne diseases are the most neglected areas of research in Pakistan. To determine the quality of water, 4 enteric viruses were studied from different localities of Peshawar, Pakistan. The study validates the viral detection method for Rotavirus (RV), Human adenovirus (HAdV), Enterovirus (EV) and Hepatitis A virus (HAV), directly from water sources of rural areas of Peshawar, KPK, Pakistan. Overall, 95 five water samples were tested; among them, 9.47% were positive for RV, 38.94% for HAdV, 48.42% for EV and 12.63% for HAV. The presence of these viruses in water was directly correlated with meteorological data. High prevalence of EV and HAdV was detected frequently in the wet season from May - September, which can be the potential cause of spreading of gastroenteritis in the population. Environmental surveillance is an additional tool to evaluate the epidemiology of enteric viruses circulating in a given community.

  16. Measurement of radon concentration in some water samples belonging to some adjoining areas of Pathankot, Punjab

    SciTech Connect

    Kumar, Ajay Sharma, Sumit

    2015-08-28

    The study of radon concentration was measured in some areas of Pathankot district, Punjab, India, from the health hazard point of view due to radon. The exposure to radon through drinking water is largely by inhalation and ingestion. RAD 7, an electronic solid state silicon detector (Durridgeco., USA) was used to measure the radon concentration in drinking water samples of the study area. The recorded values of radon concentration in these water samples are below the recommended limit by UNSCEAR and European commission. The recommended limit of radon concentration in water samples is 4 to 40 Bq/l given by UNSCEAR [1] and European commission has recommended the safe limit for radon concentration in water sample is 100 Bq/l [2].

  17. Measurement of radon concentration in some water samples belonging to some adjoining areas of Pathankot, Punjab

    NASA Astrophysics Data System (ADS)

    Kumar, Ajay; Sharma, Sumit

    2015-08-01

    The study of radon concentration was measured in some areas of Pathankot district, Punjab, India, from the health hazard point of view due to radon. The exposure to radon through drinking water is largely by inhalation and ingestion. RAD 7, an electronic solid state silicon detector (Durridgeco., USA) was used to measure the radon concentration in drinking water samples of the study area. The recorded values of radon concentration in these water samples are below the recommended limit by UNSCEAR and European commission. The recommended limit of radon concentration in water samples is 4 to 40 Bq/l given by UNSCEAR [1] and European commission has recommended the safe limit for radon concentration in water sample is 100 Bq/l [2].

  18. Analysis of n-alkanes in water samples by means of headspace solvent microextraction and gas chromatography.

    PubMed

    Zanjani, Mohammadreza Khalili; Yamini, Yadollah; Shariati, Shahab

    2006-08-25

    A simple and efficient headspace solvent microextraction (HSME) was developed for the simultaneous determination of the trace concentrations of some n-alkanes in water samples. Therefore, a microdrop of an organic solvent was extruded from the needle tip of a gas chromatographic syringe to the headspace above the surface of the solution in a sealed vial. Then the volatile organic compounds are extracted and concentrated in the microdrop. Next, the microdrop was retracted into the microsyringe and injected directly into the gas chromatograph. Experimental parameters which control the performance of HSME such as the type of microextraction solvent, organic drop and sample volume, sample stirring rate, sample solution and microsyringe needle temperatures, salt addition and exposure time profiles were investigated and optimized. Finally, the enrichment factor, dynamic linear range (DLR), limit of detection (LOD) and precision of the method were evaluated. Using optimum extraction conditions, good linearity with correlation coefficients in the range of 0.995water samples and acceptable recoveries were obtained. The results demonstrated that HSME is a rapid, accurate and effective sample preparation method and could be successfully applied for the determination of n-alkanes in water samples.

  19. A new collector for in situ pore water sampling in wetland sediment.

    PubMed

    Gao, Feng; Deng, Jiancai; Li, Qinqin; Hu, Liuming; Zhu, Jinge; Hang, Hongjuan; Hu, Weiping

    2012-01-01

    Currently available pore water samplers generally do not allow continuous monitoring of temporal variations in pore water composition. Therefore, a new type of pore water collector was designed and constructed. These collectors were constructed of polyvinyl chloride (PVC) materials, including PVC tubing with one end sealed and another end topped with a removable PVC screw-cap. A row of holes was drilled 10 cm from the sealed end of each collector. These new collectors were deployed in different layers of the sediment in a constructed wetland in Lake Taihu, China, to reveal variations in the nutrient composition of pore water with high spatial and temporal resolution. Specifically, the collectors were driven into the sediment, and the pore water flowed into the tubing via gravity. The pore water was then sampled from the PVC tubing using a portable vacuum pump, and then was taken to the lab within 20 min for analysis of the dissolved oxygen (DO) and nutrient concentration. The DO concentration of the pore water was below the detection limit for all samples, indicating that the pore water was probably not influenced by the air and that the water in the collector tube was representative of the pore water. These findings suggest that the collector is capable of measuring the temporal and spatial variations in the nutrient concentrations in pore water. Furthermore, the inexpensive material, ease of construction, minimal disturbance to the sediment and applicability for wetland sediments are advantages of the collector presented here compared with traditional pore water sampling techniques.

  20. Recovery of diverse microbes in high turbidity surface water samples using dead-end ultrafiltration

    PubMed Central

    Mull, Bonnie; Hill, Vincent R.

    2015-01-01

    Dead-end ultrafiltration (DEUF) has been reported to be a simple, field-deployable technique for recovering bacteria, viruses, and parasites from large-volume water samples for water quality testing and waterborne disease investigations. While DEUF has been reported for application to water samples having relatively low turbidity, little information is available regarding recovery efficiencies for this technique when applied to sampling turbid water samples such as those commonly found in lakes and rivers. This study evaluated the effectiveness of a DEUF technique for recoveringMS2 bacteriophage, enterococci, Escherichia coli, Clostridium perfringens, and Cryptosporidium parvum oocysts in surface water samples having elevated turbidity. Average recovery efficiencies for each study microbe across all turbidity ranges were: MS2 (66%), C. parvum (49%), enterococci (85%), E. coli (81%), and C. perfringens (63%). The recovery efficiencies for MS2 and C. perfringens exhibited an inversely proportional relationship with turbidity, however no significant differences in recovery were observed for C. parvum, enterococci, or E. coli. Although ultrafilter clogging was observed, the DEUF method was able to process 100-L surface water samples at each turbidity level within 60 min. This study supports the use of the DEUF method for recovering a wide array of microbes in large-volume surface water samples having medium to high turbidity. PMID:23064261

  1. Analysis of uranium in drinking water samples using laser induced fluorimetry.

    PubMed

    Rani, Asha; Singh, Surinder

    2006-08-01

    Uranium concentration in drinking water samples collected from some areas of Punjab and Himachal Pradesh has been measured using a laser induced fluorimetry technique. The sources of water comprise hand pumps and tube wells. Uranium concentration in the water samples from Punjab varies from 1.39 +/- 0.16 to 98.25 +/- 2.06 ppb with a mean value of 19.84 +/- 0.87 ppb. The uranium concentration in most of the drinking water samples from Punjab exceeds the safe limit recommended by the World Health Organization. However, the uranium concentration in water samples from Himachal Pradesh is well within the recommended levels. The annual effective dose equivalent associated with drinking water due to uranium concentration is estimated from its annual intake using dosimetric information based on ICRP Report 72. The resulting value of the annual effective dose from drinking water sources is in the range of 0.13 to 81.59 muSv. The annual effective dose received by the population due to the consumption of drinking water from these areas is well within the recommended limit. In order to check the accuracy of the technique a few water samples were also analyzed using a fission track registration technique. A good agreement has been observed between the uranium values determined by these techniques.

  2. Enhancement of critical heat flux in subcooled flow boiling of water by use of a volatile additive

    SciTech Connect

    Pabisz, R.A. Jr.; Bergles, A.E.

    1996-12-31

    The present investigation considers the effect of a 1-pentanol additive in water on the critical heat flux (CHF) and pressure drop in forced subcooled boiling. A small quantity of 1-pentanol was added to distilled water with the objective of getting an approximate 2% by weight mixture, which had been found to give superior performance in previous studies of pool and flow boiling. Experiments were performed using stainless steel tubes with internal diameters of 4.4 and 6.1 mm. Tests were conducted with mass fluxes of 4,400 kg/m{sup 2}s, exit pressures of 9 bar, length-to-diameter ratios of 25, and exit subcoolings from 65 to 90 C. Test sections were heated directly by DC power, and critical heat flux data were inferred from test-section burnout. The alcohol concentration was periodically checked by draining off a sample and performing a Proton Nuclear Magnetic Resonance scan on the mixture. At high subcoolings, the mixture exhibited an increase in the critical heat flux over that of pure water. However at low subcoolings there is a decrease in the critical heat flux. The increases in critical heat flux noted with the 1-pentanol mixture in this experiment were not as large as would be expected from saturated pool boiling results published by Van Stralen (1959). Pressure drop data for both the mixture and the pure water also were recorded. The 1-pentanol mixture, in general, exhibited larger pressure drops for the same conditions. Subcooled flow boiling has a wide array of commercial cooling applications, including blades in gas turbines, high power laser optics, plasma-facing components in fusion reactors, supercomputers, etc.

  3. Effects of water soaking and/or sodium polystyrene sulfonate addition on potassium content of foods.

    PubMed

    Picq, Christian; Asplanato, Marion; Bernillon, Noémie; Fabre, Claudie; Roubeix, Mathilde; Ricort, Jean-Marc

    2014-09-01

    In this study, we determined, by atomic absorption spectrophotometry, the potassium amount leached by soaking or boiling foods identified by children suffering from chronic renal failure as "pleasure food" and that they cannot eat because of their low-potassium diet, and evaluated whether addition of sodium polystyrene sulfonate resin (i.e. Kayexalate®) during soaking or boiling modulated potassium loss. A significant amount of potassium content was removed by soaking (16% for chocolate and potato, 26% for apple, 37% for tomato and 41% for banana) or boiling in a large amount of water (73% for potato). Although Kayexalate® efficiently dose-dependently removed potassium from drinks (by 48% to 73%), resin addition during soaking or boiling did not eliminate more potassium from solid foods. Our results therefore provide useful information for dietitians who elaborate menus for people on potassium-restricted diets and would give an interesting alternative to the systematic elimination of all potassium-rich foods from their diet.

  4. Fabric phase sorptive extraction: Two practical sample pretreatment techniques for brominated flame retardants in water.

    PubMed

    Huang, Guiqi; Dong, Sheying; Zhang, Mengfei; Zhang, Haihan; Huang, Tinglin

    2016-09-15

    Sample pretreatment is the critical section for residue monitoring of hazardous pollutants. In this paper, using the cellulose fabric as host matrix, three extraction sorbents such as poly (tetrahydrofuran) (PTHF), poly (ethylene glycol) (PEG) and poly (dimethyldiphenylsiloxane) (PDMDPS), were prepared on the surface of the cellulose fabric. Two practical extraction techniques including stir bar fabric phase sorptive extraction (stir bar-FPSE) and magnetic stir fabric phase sorptive extraction (magnetic stir-FPSE) have been designed, which allow stirring of fabric phase sorbent during the whole extraction process. In the meantime, three brominated flame retardants (BFRs) [tetrabromobisphenol A (TBBPA), tetrabromobisphenol A bisallylether (TBBPA-BAE), tetrabromobisphenol A bis(2,3-dibromopropyl)ether (TBBPA-BDBPE)] in the water sample were selected as model analytes for the practical evaluation of the proposed two techniques using high-performance liquid chromatography (HPLC). Moreover, various experimental conditions affecting extraction process such as the type of fabric phase, extraction time, the amount of salt and elution conditions were also investigated. Due to the large sorbent loading capacity and unique stirring performance, both techniques possessed high extraction capability and fast extraction equilibrium. Under the optimized conditions, high recoveries (90-99%) and low limits of detection (LODs) (0.01-0.05 μg L(-1)) were achieved. In addition, the reproducibility was obtained by evaluating the intraday and interday precisions with relative standard deviations (RSDs) less than 5.1% and 6.8%, respectively. The results indicated that two pretreatment techniques were promising and practical for monitoring of hazardous pollutants in the water sample. Due to low solvent consumption and high repeated use performance, proposed techniques also could meet green analytical criteria.

  5. A study on the prevalence of Aeromonas spp. and its enterotoxin genes in samples of well water, tap water, and bottled water

    PubMed Central

    Didugu, Hareesh; Thirtham, Madhavarao; Nelapati, Krishnaiah; Reddy, K Kondal; Kumbhar, Baba Saheb; Poluru, Anusha; Pothanaboyina, Guruvishnu

    2015-01-01

    Aim: The aim of this work was to study the prevalence of Aeromonas spp. and its enterotoxin genes in various water sources. Materials and Methods: 125 samples (50 from well water, 50 from tap water, and 25 from bottled water) were collected from various sources in and around Greater Hyderabad Municipal Corporation and examined for the presence of aeromonads by both cultural and polymerase chain reaction (PCR) assay. Alkaline peptone water with ampicillin was used as enrichment. Aeromonas isolation medium and ampicillin dextrin agar were used as selective media. The boiling and snap chilling method was used for DNA extraction. Primers targeted against 16S rRNA, aer, and ast were used to identify aeromonads and its enterotoxins. Results: 48%, 18%, and 12% of well water, tap water, and bottled water samples were found positive by cultural assay with an overall prevalence of 28.8%. Aeromonads were detected in 32 % (52% in well water, 20% in tap water, and 16% in bottled water) of samples by PCR assay. Aerolysin (aer) gene was noticed in 34.6%, 20%, and 0% of well water, tap water, and bottled water samples, respectively, with an overall prevalence of 27.5%. Thermostable cytotonic enterotoxin (ast) was observed in 37.5% (42.3% in well water, 30% in tap water, and 25% in bottled mineral water) of samples. Conclusions: Presence of aeromonads and its toxin genes in various sources of water is of public health concern and emphasizes the need for necessary preventive measures to tackle the problem. PMID:27047024

  6. Multiport well design for sampling of ground water at closely spaced vertical intervals

    SciTech Connect

    Delin, G.N.; Landon, M.K.

    1996-11-01

    Detailed vertical sampling is useful in aquifers where vertical mixing is limited and steep vertical gradients in chemical concentrations are expected. Samples can be collected at closely spaced vertical intervals from nested wells with short screened intervals. However, this approach may not be appropriate in all situations. An easy-to-construct and easy-to-install multiport sampling well to collect ground-water samples from closely spaced vertical intervals was developed and tested. The multiport sampling well was designed to sample ground water from surficial sand-and-gravel aquifers. The device consists of multiple stainless-steel tubes within a polyvinyl chloride (PVC) protective casing. The tubes protrude through the wall of the PVC casing at the desired sampling depths. A peristaltic pump is used to collect ground-water samples form the sampling ports. The difference in hydraulic head between any two sampling ports can be measured with a vacuum pump and a modified manometer. The usefulness and versatility of this multiport well design was demonstrated at an agricultural research site near Princeton, Minnesota where sampling ports were installed to a maximum depth of about 12 m below land surface. Trace experiments were conducted using potassium bromide to document the degree to which short-circuiting occurred between sampling ports. Samples were successfully collected for analysis of major cations and anions, nutrients, selected herbicides, isotopes, dissolved gases, and chlorofluorocarbon concentrations.

  7. Multiport well design for sampling of ground water at closely spaced vertical intervals

    USGS Publications Warehouse

    Delin, G.N.; Landon, M.K.

    1996-01-01

    Detailed vertical sampling is useful in aquifers where vertical mixing is limited and steep vertical gradients in chemical concentrations are expected. Samples can be collected at closely spaced vertical intervals from nested wells with short screened intervals. However, this approach may not be appropriate in all situations. An easy-to-construct and easy-to-install multiport sampling well to collect ground-water samples from closely spaced vertical intervals was developed and tested. The multiport sampling well was designed to sample ground water from surficial sand-and-gravel aquifers. The device consists of multiple stainless-steel tubes within a polyvinyl chloride (PVC) protective casing. The tubes protrude through the wall of the PVC casing at the desired sampling depths. A peristaltic pump is used to collect ground-water samples from the sampling ports. The difference in hydraulic head between any two sampling ports can be measured with a vacuum pump and a modified manometer. The usefulness and versatility of this multiport well design was demonstrated at an agricultural research site near Princeton, Minnesota where sampling ports were installed to a maximum depth of about 12 m below land surface. Tracer experiments were conducted using potassium bromide to document the degree to which short-circuiting occurred between sampling ports. Samples were successfully collected for analysis of major cations and anions, nutrients, selected herbicides, isotopes, dissolved gases, and chlorofluorcarbon concentrations.

  8. The effect of quantity and timing of brine addition on water binding and textural characteristics of cooked beef rolls.

    PubMed

    Pietrasik, Z; Shand, P J

    2003-10-01

    The combined influence of quantity and timing of water/sodium chloride/phosphate addition on quality characteristics of beef rolls processed with 25 or 50% brine level was investigated. Properties of beef rolls were determined by measuring hydration and textural characteristics. The higher level of brine addition (50%) had detrimental effects on product water binding and textural characteristics. Late addition of brine/water during tumbling (i.e. during the last hour) resulted in rolls which were less hard, chewy and elastic, and had poorer water holding properties. Addition of brine in two parts favourably affected hydration properties and thermal stability, yielding lower cooking loss and purge and higher WHC, irrespective of level of brine addition. It also increased hardness and chewiness and improved springiness, cohesiveness and bind of cooked beef rolls.

  9. STANDARD-REFERENCE WATER-SUSPENDED SEDIMENT SAMPLE FOR TOTAL RECOVERABLE METALS.

    USGS Publications Warehouse

    Fishman, Marvin J.; Malo, Bernard A.; Boyle, Delora K.

    1984-01-01

    The U. S. Geological Survey has been preparing and maintaining a library of standard-reference water samples for dissolved inorganic constituents for 19 years. Recently, the reference-sample program was expanded to include a water-suspended sediment mixture for the determination of total recoverable metals. An interlaboratory round-robin study was conducted. Digestion procedures used by the U. S. Geological Survey and the U. S. Environmental Protection Agency were used to solubilize the metals before their measurement. The data indicate that both digestion procedures for total recoverable metals are essentially equivalent. Precision data are comparable to those data obtained in standard-reference water samples for dissolved metals.

  10. Predictors of victim disclosure in child sexual abuse: Additional evidence from a sample of incarcerated adult sex offenders.

    PubMed

    Leclerc, Benoit; Wortley, Richard

    2015-05-01

    The under-reporting of child sexual abuse by victims is a serious problem that may prolong the suffering of victims and leave perpetrators free to continue offending. Yet empirical evidence indicates that victim disclosure rates are low. In this study, we perform regression analysis with a sample of 369 adult child sexual offenders to examine potential predictors of victim disclosure. Specifically, we extend the range of previously examined potential predictors of victim disclosure and investigate interaction effects in order to better capture under which circumstances victim disclosure is more likely. The current study differs from previous studies in that it examines the impact of victim and offense variables on victim disclosure from the perspective of the offender. In line with previous studies, we found that disclosure increased with the age of the victim and if penetration had occurred. In addition, we found that disclosure increased when the victim came from a non-dysfunctional family and resisted the abuse. The presence of an interaction effect highlighted the impact of the situation on victim disclosure. This effect indicated that as victims get older, they are more likely to disclose the abuse when they are not living with the offender at the time of abuse, but less likely to do so when they are living with the offender at the time of abuse. These findings are discussed in relation to previous studies and the need to facilitate victim disclosure.

  11. LC-ESI-MS determination of diethylene glycol pollution in sea water samples collected around gas extraction platform plants.

    PubMed

    Cappiello, A; Famiglini, G; Palma, P; Termopoli, V; Trufelli, H; Di Mento, R; Mannozzi, M

    2009-11-15

    Produced formation waters (PFWs) represent the largest aqueous wastes that are normally discharged into the marine environment during the offshore gas production processes. The chemical additive diethylene glycol (DEG) is widely used in the gas production line and therefore can be found in the PFW, becoming of environmental concern. In this study, a new method has been developed for trace determination of DEG in sea water samples collected around offshore gas platforms. The method is based on liquid chromatography coupled to electrospray ionization mass spectrometry (LC-ESI-MS). Prior to analysis, water samples were derivatized using the Schotten-Baumann method for the benzoylation of glycols. The derivatization procedure allowed us to maximize the ESI-MS response of DEG and minimize the influence of interfering compounds. The method was validated and allowed a quantification of DEG in sea water samples with a method LOD of 0.4 ng/mL. The applicability of the procedure was demonstrated by analyzing sea water samples collected around eight gas platforms located in the Adriatic Sea (Italy).

  12. Monitoring the aftermath of Flint drinking water contamination crisis: Another case of sampling bias?

    PubMed

    Goovaerts, Pierre

    2017-07-15

    The delay in reporting high levels of lead in Flint drinking water, following the city's switch to the Flint River as its water supply, was partially caused by the biased selection of sampling sites away from the lead pipe network. Since Flint returned to its pre-crisis source of drinking water, the State has been monitoring water lead levels (WLL) at selected "sentinel" sites. In a first phase that lasted two months, 739 residences were sampled, most of them bi-weekly, to determine the general health of the distribution system and to track temporal changes in lead levels. During the same period, water samples were also collected through a voluntary program whereby concerned citizens received free testing kits and conducted sampling on their own. State officials relied on the former data to demonstrate the steady improvement in water quality. A recent analysis of data collected by voluntary sampling revealed, however, an opposite trend with lead levels increasing over time. This paper looks at potential sampling bias to explain such differences. Although houses with higher WLL were more likely to be sampled repeatedly, voluntary sampling turned out to reproduce fairly well the main characteristics (i.e. presence of lead service lines (LSL), construction year) of Flint housing stock. State-controlled sampling was less representative; e.g., sentinel sites with LSL were mostly built between 1935 and 1950 in lower poverty areas, which might hamper our ability to disentangle the effects of LSL and premise plumbing (lead fixtures and pipes present within old houses) on WLL. Also, there was no sentinel site with LSL in two of the most impoverished wards, including where the percentage of children with elevated blood lead levels tripled following the switch in water supply. Correcting for sampling bias narrowed the gap between sampling programs, yet overall temporal trends are still opposite.

  13. Effects of water sample preservation and storage conditions on nitrate concentrations

    SciTech Connect

    Li, Y.C.; Alva, A.K.; Calvert, D.V.; Zhang, M. |

    1995-12-31

    USEPA method 300 requires water samples should be stored at 4 C immediately after collection and NO{sub 3}-N concentration analyzed within 48 hr of sample collection. Many research and commercial laboratories find it is difficult to meet this holding time. Water samples are often stored for several days at 4 C or {minus}20 C until analysis. The objective of this study was to evaluate effects of groundwater sample pretreatment, storage temperatures, and holding times on concentrations of NO{sub 3}-N. The storage of samples at 25 C decreased concentrations of NO{sub 3}-N by 1.7% and 12.5% for 48 hr and 50 days, respectively. No significant changes were observed during the 50 days storage at 4 C or {minus}20 C. Acidification of water samples at 4 C had no significant effect on NO{sub 3}-N concentration up to 50-day holding time.

  14. Well installation and documentation, and ground-water sampling protocols for the pilot National Water-Quality Assessment Program

    USGS Publications Warehouse

    Hardy, M.A.; Leahy, P.P.; Alley, W.M.

    1989-01-01

    Several pilot projects are being conducted as part of the National Water Quality Assessment (NAWQA) Program. The purpose of the pilot program is to test and refine concepts for a proposed full-scale program. Three of the pilot projects are specifically designed to assess groundwater. The purpose of this report is to describe the criteria that are being used in the NAWQA pilot projects for selecting and documenting wells, installing new wells, and sampling wells for different water quality constituents. Guidelines are presented for the selection of wells for sampling. Information needed to accurately document each well includes site characteristics related to the location of the well, land use near the well, and important well construction features. These guidelines ensure the consistency of the information collected and will provide comparable data for interpretive purposes. Guidelines for the installation of wells are presented and include procedures that need to be followed for preparations prior to drilling, the selection of the drilling technique and casing type, the grouting procedure, and the well-development technique. A major component of the protocols is related to water quality sampling. Tasks are identified that need to be completed prior to visiting the site for sampling. Guidelines are presented for purging the well prior t sampling, both in terms of the volume of water pumped and the chemical stability of field parameters. Guidelines are presented concerning sampler selection as related to both inorganic and organic constituents. Documentation needed to describe the measurements and observations related to sampling each well and treating and preserving the samples are also presented. Procedures are presented for the storage and shipping of water samples, equipment cleaning, and quality assurance. Quality assurance guidelines include the description of the general distribution of the various quality assurance samples (blanks, spikes, duplicates, and

  15. Understanding the origin and evolution of water in the Moon through lunar sample studies.

    PubMed

    Anand, Mahesh; Tartèse, Romain; Barnes, Jessica J

    2014-09-13

    A paradigm shift has recently occurred in our knowledge and understanding of water in the lunar interior. This has transpired principally through continued analysis of returned lunar samples using modern analytical instrumentation. While these recent studies have undoubtedly measured indigenous water in lunar samples they have also highlighted our current limitations and some future challenges that need to be overcome in order to fully understand the origin, distribution and evolution of water in the lunar interior. Another exciting recent development in the field of lunar science has been the unambiguous detection of water or water ice on the surface of the Moon through instruments flown on a number of orbiting spacecraft missions. Considered together, sample-based studies and those from orbit strongly suggest that the Moon is not an anhydrous planetary body, as previously believed. New observations and measurements support the possibility of a wet lunar interior and the presence of distinct reservoirs of water on the lunar surface. Furthermore, an approach combining measurements of water abundance in lunar samples and its hydrogen isotopic composition has proved to be of vital importance to fingerprint and elucidate processes and source(s) involved in giving rise to the lunar water inventory. A number of sources are likely to have contributed to the water inventory of the Moon ranging from primordial water to meteorite-derived water ice through to the water formed during the reaction of solar wind hydrogen with the lunar soil. Perhaps two of the most striking findings from these recent studies are the revelation that at least some portions of the lunar interior are as water-rich as some Mid-Ocean Ridge Basalt source regions on Earth and that the water in the Earth and the Moon probably share a common origin.

  16. Understanding the origin and evolution of water in the Moon through lunar sample studies

    PubMed Central

    Anand, Mahesh; Tartèse, Romain; Barnes, Jessica J.

    2014-01-01

    A paradigm shift has recently occurred in our knowledge and understanding of water in the lunar interior. This has transpired principally through continued analysis of returned lunar samples using modern analytical instrumentation. While these recent studies have undoubtedly measured indigenous water in lunar samples they have also highlighted our current limitations and some future challenges that need to be overcome in order to fully understand the origin, distribution and evolution of water in the lunar interior. Another exciting recent development in the field of lunar science has been the unambiguous detection of water or water ice on the surface of the Moon through instruments flown on a number of orbiting spacecraft missions. Considered together, sample-based studies and those from orbit strongly suggest that the Moon is not an anhydrous planetary body, as previously believed. New observations and measurements support the possibility of a wet lunar interior and the presence of distinct reservoirs of water on the lunar surface. Furthermore, an approach combining measurements of water abundance in lunar samples and its hydrogen isotopic composition has proved to be of vital importance to fingerprint and elucidate processes and source(s) involved in giving rise to the lunar water inventory. A number of sources are likely to have contributed to the water inventory of the Moon ranging from primordial water to meteorite-derived water ice through to the water formed during the reaction of solar wind hydrogen with the lunar soil. Perhaps two of the most striking findings from these recent studies are the revelation that at least some portions of the lunar interior are as water-rich as some Mid-Ocean Ridge Basalt source regions on Earth and that the water in the Earth and the Moon probably share a common origin. PMID:25114308

  17. Identification and quantification of pesticide residues in water samples of Dhamrai Upazila, Bangladesh

    NASA Astrophysics Data System (ADS)

    Hasanuzzaman, M.; Rahman, M. A.; Salam, M. A.

    2016-10-01

    Being agricultural country, different types of pesticides are widely used in Bangladesh to prevent the crop losses due to pest attack which are ultimately drain to the water bodies. The present study was conducted to identify and quantify the organochlorine (DDT, DDE and DDD), organophosphorus (malathion, diazinon and chloropyrifos) and carbamate (carbaryl) residues in water samples of different sources from Dhamrai upazila of Bangladesh using high performance liquid chromatography (HPLC) equipped with ultra violate (UV) detector. Thirty water samples from fish pond, cultivated land and tube-well were collected in winter season to analyze the pesticide residues. Among the organophosphorus pesticides, malathion was present in seven water samples ranging from 42.58 to 922.8 μg/L, whereas diazinon was detected in water sample-8 (WS-8) and the concentration was 31.5 μg/L. None of the tested water samples was found to be contaminated with chlorpyrifos, carbaryl or DDT and its metabolites (DDE and DDD). Except for a tube-well water sample, concentrations of the detected residues are above the acceptable limit for human body as assigned by different organizations. To avoid the possible health hazards, the indiscriminate application of pesticides should be restricted and various substitute products like bio-pesticide should be introduced in a broad scale as soon as possible.

  18. Detection of Acanthamoeba and Toxoplasma in River Water Samples by Molecular Methods in Iran

    PubMed Central

    MAHMOUDI, Mohammad Reza; KAZEMI, Bahram; HAGHIGHI, Ali; KARANIS, Panagiotis

    2015-01-01

    Background: Free-living amoebae such as Acanthamoeba species may act as carriers of Cryptosporidium and Toxoplasma oocysts, thus, may play an important role in the water-borne transmission of these parasites. In the present study, a loop mediated isothermal amplification (LAMP) method for detection of Toxoplasma and a PCR assay were developed for investigation of Acanthamoeba in environmental water samples. Methods: A total of 34 samples were collected from the surface water in Guilan Province. Water samples were filtrated with membrane filters and followed by DNA extraction. PCR and LAMP methods used for detection of the protozoan parasites Acanthamoeba and Toxoplasma respectively. Results: Totally 30 and 2 of 34 samples were positive for Acanthamoeba and Toxoplasma oocysts respectively. Two samples were positive for both investigated parasites. Conclusion: The investigated water supplies, are contaminated by Toxoplasma and Acanthamoeba (oo)cystes. Acanthamoeba may play an important role in water-borne transmission of Toxoplasma in the study area. For the first time in Iran, protocol of LAMP method was used effectively for the detection of Toxoplasma in surface water samples in Iran. PMID:26246823

  19. Determination of natural radioactivity by gross alpha and beta measurements in ground water samples.

    PubMed

    Turhan, S; Ozçitak, E; Taşkin, H; Varinlioğlu, A

    2013-06-01

    In this study, the activity concentrations of the gross α and β in ground water samples collected from the different drilled wells in Nevşehir province were measured to assess annual effective dose due to the ingestion of the water samples. Nevşehir province is one of the major cities of Cappadocia Region which is a popular tourist destination as it has many areas with unique geological, historic, and cultural features. Sampling and measurements were carried out in the autumn of 2011 and the spring of 2012. The values of the activity concentrations of the gross α and β measured in the water samples ranged from 80 to 380 mBq L(-1) with a mean of 192 mBq L(-1) and 120-3470 mBq L(-1) with a mean of 579 mBq L(-1) respectively. All values of the gross α were lower than the limit value of 500 mBq L(-1) while two ground water samples were found to have gross β activity concentrations of greater than 1000 mBq L(-1). Therefore two water samples were the subject of further radioisotope-specific analysis. The obtained result indicated that the elevated activity concentrations of the gross β in these water samples are dominated by (40)K activity. Annual effective doses ranged from 0.04 to 0.20 mSv y(-1).

  20. Genotypic Characterization of Cryptosporidium hominis from Water Samples in São Paulo, Brazil

    PubMed Central

    Araújo, Ronalda S.; Dropa, Milena; Fernandes, Licia N.; Carvalho, Terezinha T.; Sato, Maria Inês Z.; Soares, Rodrigo M.; Matté, Glavur R.; Matté, Maria Helena

    2011-01-01

    The protozoan parasite Cryptosporidium has emerged as one of the most important water contaminants, causing waterborne outbreaks of diarrheal diseases worldwide. The small size of oocysts under the microscope and the possibility of changes in characteristics of oocysts, mainly in environmental samples, make the taxonomy of the genus difficult if morphologic characteristics are considered. This limitation encouraged the application of molecular methods to identify this microorganism. The aim of this study was to detect and identify by nested-polymerase chain reaction oocysts of Cryptosporidium present in water samples in the state of São Paulo, Brazil. Water samples were concentrated through a membrane filter, DNA was extracted by using a standard technique, and both amplification reactions used forward and reverse oligonucleotides that were complementary to Cryptosporidium 18S ribosomal RNA gene sequences. Thirty water samples from different sites of collection in the state of São Paulo were evaluated. Cryptosporidium oocysts were detected in 30% of the samples. By genoptyping, C. hominis and Cryptosporidium sp. were identified in recreational water and C. meleagridis was identified in surface water samples. This is the first report of C. hominis in environmental samples in Brazil. Although identification of Cryptosporidium is still a difficult task, molecular methods are essential for specific identification and are a helpful tool to aid to understand the epidemiology of this parasite in Brazil. PMID:22049036

  1. Methods for collecting algal samples as part of the National Water-Quality Assessment Program

    USGS Publications Warehouse

    Porter, Stephen D.; Cuffney, Thomas F.; Gurtz, Martin E.; Meador, Michael R.

    1993-01-01

    Benthic algae (periphyton) and phytoplankton communities are characterized in the U.S. Geological Survey's National Water-Quality Assessment Program as part of an integrated physical, chemical, and biological assessment of the Nation's water quality. This multidisciplinary approach provides multiple lines of evidence for evaluating water-quality status and trends, and for refining an understanding of the factors that affect water-quality conditions locally, regionally, and nationally. Water quality can be characterized by evaluating the results of qualitative and quantitative measurements of the algal community. Qualitative periphyton samples are collected to develop of list of taxa present in the sampling reach. Quantitative periphyton samples are collected to measure algal community structure within selected habitats. These samples of benthic algal communities are collected from natural substrates, using the sampling methods that are most appropriate for the habitat conditions. Phytoplankton samples may be collected in large nonwadeable streams and rivers to meet specific program objectives. Estimates of algal biomass (chlorophyll content and ash-free dry mass) also are optional measures that may be useful for interpreting water-quality conditions. A nationally consistent approach provides guidance on site, reach, and habitat selection, as well as information on methods and equipment for qualitative and quantitative sampling. Appropriate quality-assurance and quality-control guidelines are used to maximize the ability to analyze data locally, regionally, and nationally.

  2. Idaho's surface-water-quality monitoring program: results from five sites sampled during water years 1990-93

    USGS Publications Warehouse

    ,

    1994-01-01

    In 1990, the U.S. Geological Survey (USGS), in cooperation with the Idaho Department of Health and Welfare, Division of Environmental Quality, implemented a statewide water-quality monitoring program in response to Idaho's antidegradation policy as required by the Clean Water Act. The program objective is to provide water-quality managers with a coordinated statewide network to detect trends in surface-water quality. The monitoring program includes the collection and analysis of samples from 56 sites on the Bear, Clearwater, Kootenai, Pend Oreille, Salmon, Snake, and Spokane Rivers and their tributaries (fig. 1). Samples are collected every year at 5 sites (annual sites) in drainage basins where long-term water-quality management is practiced, every other year at 19 sites (biennial sites) in basins where land and water uses change slowly, and every third year at 32 sites (triennial sites) where future development may affect water quality. Each year, 25 of the 56 sites are sampled. This report discusses results of sampling at five annual sites. During water years 1990-93 (October 1, 1989, through September 30, 1993), samples were collected six times per year at the five annual sites (fig. 1). Onsite analyses were made for discharge, specific conductance, pH, temperature, dissolved oxygen, bacteria (fecal coliform and fecal streptococci), and alkalinity. Laboratory analyses were made for major ions, nutrients, trace elements, and suspended sediment. Suspended sediment, nitrate, fecal coliform, trace elements, and specific conductance were used to characterize surface-water quality. Because concentrations of all trace elements except zinc were near detection limits, only zinc is discussed.

  3. Ground-Water Data-Collection Protocols and Procedures for the National Water-Quality Assessment Program: Collection and Documentation of Water-Quality Samples and Related Data

    USGS Publications Warehouse

    Koterba, Michael T.; Wilde, Franceska D.; Lapham, Wayne W.

    1995-01-01

    Protocols for ground-water sampling are described in a report written in 1989 as part of the pilot program for the National Water-Quality Assessment (NAWQA) Program of the U.S. Geological Survey (USGS). These protocols have been reviewed and revised to address the needs of the full-scale implementation of the NAWQA Program that began in 1991. This report, which is a collaborative effort between the NAWQA Program and the USGS Office of Water Quality, is the result of that review and revision. This report describes protocols and recommended procedures for the collection of water-quality samples and related data from wells for the NAWQA Program. Protocols and recommended procedures discussed include (1) equipment setup and other preparations for data collection; (2) well purging and field measurements; (3) collecting and processing ground-water-quality samples; (4) equipment decontamination; (5) quality-control sampling; and (6) sample handling and shipping.

  4. “Nanofiltration” Enabled by Super-Absorbent Polymer Beads for Concentrating Microorganisms in Water Samples

    PubMed Central

    Xie, Xing; Bahnemann, Janina; Wang, Siwen; Yang, Yang; Hoffmann, Michael R.

    2016-01-01

    Detection and quantification of pathogens in water is critical for the protection of human health and for drinking water safety and security. When the pathogen concentrations are low, large sample volumes (several liters) are needed to achieve reliable quantitative results. However, most microbial identification methods utilize relatively small sample volumes. As a consequence, a concentration step is often required to detect pathogens in natural waters. Herein, we introduce a novel water sample concentration method based on superabsorbent polymer (SAP) beads. When SAP beads swell with water, small molecules can be sorbed within the beads, but larger particles are excluded and, thus, concentrated in the residual non-sorbed water. To illustrate this approach, millimeter-sized poly(acrylamide-co-itaconic acid) (P(AM-co-IA)) beads are synthesized and successfully applied to concentrate water samples containing two model microorganisms: Escherichia coli and bacteriophage MS2. Experimental results indicate that the size of the water channel within water swollen P(AM-co-IA) hydrogel beads is on the order of several nanometers. The millimeter size coupled with a negative surface charge of the beads are shown to be critical in order to achieve high levels of concentration. This new concentration procedure is very fast, effective, scalable, and low-cost with no need for complex instrumentation. PMID:26876979

  5. "Nanofiltration" Enabled by Super-Absorbent Polymer Beads for Concentrating Microorganisms in Water Samples.

    PubMed

    Xie, Xing; Bahnemann, Janina; Wang, Siwen; Yang, Yang; Hoffmann, Michael R

    2016-02-15

    Detection and quantification of pathogens in water is critical for the protection of human health and for drinking water safety and security. When the pathogen concentrations are low, large sample volumes (several liters) are needed to achieve reliable quantitative results. However, most microbial identification methods utilize relatively small sample volumes. As a consequence, a concentration step is often required to detect pathogens in natural waters. Herein, we introduce a novel water sample concentration method based on superabsorbent polymer (SAP) beads. When SAP beads swell with water, small molecules can be sorbed within the beads, but larger particles are excluded and, thus, concentrated in the residual non-sorbed water. To illustrate this approach, millimeter-sized poly(acrylamide-co-itaconic acid) (P(AM-co-IA)) beads are synthesized and successfully applied to concentrate water samples containing two model microorganisms: Escherichia coli and bacteriophage MS2. Experimental results indicate that the size of the water channel within water swollen P(AM-co-IA) hydrogel beads is on the order of several nanometers. The millimeter size coupled with a negative surface charge of the beads are shown to be critical in order to achieve high levels of concentration. This new concentration procedure is very fast, effective, scalable, and low-cost with no need for complex instrumentation.

  6. “Nanofiltration” Enabled by Super-Absorbent Polymer Beads for Concentrating Microorganisms in Water Samples

    NASA Astrophysics Data System (ADS)

    Xie, Xing; Bahnemann, Janina; Wang, Siwen; Yang, Yang; Hoffmann, Michael R.

    2016-02-01

    Detection and quantification of pathogens in water is critical for the protection of human health and for drinking water safety and security. When the pathogen concentrations are low, large sample volumes (several liters) are needed to achieve reliable quantitative results. However, most microbial identification methods utilize relatively small sample volumes. As a consequence, a concentration step is often required to detect pathogens in natural waters. Herein, we introduce a novel water sample concentration method based on superabsorbent polymer (SAP) beads. When SAP beads swell with water, small molecules can be sorbed within the beads, but larger particles are excluded and, thus, concentrated in the residual non-sorbed water. To illustrate this approach, millimeter-sized poly(acrylamide-co-itaconic acid) (P(AM-co-IA)) beads are synthesized and successfully applied to concentrate water samples containing two model microorganisms: Escherichia coli and bacteriophage MS2. Experimental results indicate that the size of the water channel within water swollen P(AM-co-IA) hydrogel beads is on the order of several nanometers. The millimeter size coupled with a negative surface charge of the beads are shown to be critical in order to achieve high levels of concentration. This new concentration procedure is very fast, effective, scalable, and low-cost with no need for complex instrumentation.

  7. Solvent isotope effects on the kinetics of nucleophilic addition of water to a. beta. -nitrostyrene

    SciTech Connect

    Crowell, T.I.

    1983-09-23

    The hydrolysis rate of 3,4-(methylenedioxy)-..beta..-nitrostyrene (S) has been measured in H/sub 2/O and in 99% D/sub 2/O buffer solutions from pH -0.9 to 10.6. The kinetic solvent isotope effect (KSIE), k(H/sub 2/O)/k(D/sub 2/O), is 6.2 at pH 2.5, where k is independent of pH in both solvents and attains a higher value, approximately 22, at about pH 6.2. The isotope effects k/sub i/(H/sub 2/O)/k/sub i/(D/sub 2/O) on the rate constants for the individual steps of the mechanism have been determined and their contributions to the overall KSIE evaluated. Accordingly, the KSIE on the pH-rate plateau at pH 1-4 can be separated into two factors: 5.0 for K/sub 12/, the ionization constant of S as a pseudo-base in water; and 1.4 for k/sub 3//sup H/, the rate constant for rate-controlling protonation of the resulting anion by H/sub 3/O/sup +/. At pH 6.2, the higher KSIE (7.6) on k/sub 3//sup H/sub 2/O/ becomes important while the uncatalyzed addition of water to the double bond is partly rate controlling. The rate at the midpoint of a proton-inventory plot (49.5% D/sub 2/O) shows a negative deviation from linearity of 18%. 2 figures, 2 tables.

  8. Cryptosporidium Oocyst Detection in Water Samples: Floatation Technique Enhanced with Immunofluorescence Is as Effective as Immunomagnetic Separation Method

    PubMed Central

    Koompapong, Khuanchai; Sutthikornchai, Chantira

    2009-01-01

    Cryptosporidium can cause gastrointestinal diseases worldwide, consequently posing public health problems and economic burden. Effective techniques for detecting contaminated oocysts in water are important to prevent and control the contamination. Immunomagnetic separation (IMS) method has been widely employed recently due to its efficiency, but, it is costly. Sucrose floatation technique is generally used for separating organisms by using their different specific gravity. It is effective and cheap but time consuming as well as requiring highly skilled personnel. Water turbidity and parasite load in water sample are additional factors affecting to the recovery rate of those 2 methods. We compared the efficiency of IMS and sucrose floatation methods to recover the spiked Cryptosporidium oocysts in various turbidity water samples. Cryptosporidium oocysts concentration at 1, 101, 102, and 103 per 10 µl were spiked into 3 sets of 10 ml-water turbidity (5, 50, and 500 NTU). The recovery rate of the 2 methods was not different. Oocyst load at the concentration < 102 per 10 ml yielded unreliable results. Water turbidity at 500 NTU decreased the recovery rate of both techniques. The combination of sucrose floatation and immunofluorescense assay techniques (SF-FA) showed higher recovery rate than IMS and immunofluorescense assay (IMS-FA). We used this SF-FA to detect Cryptosporidium and Giardia from the river water samples and found 9 and 19 out of 30 (30% and 63.3%) positive, respectively. Our results favored sucrose floatation technique enhanced with immunofluorescense assay for detecting contaminated protozoa in water samples in general laboratories and in the real practical setting. PMID:19967082

  9. Cryptosporidium oocyst detection in water samples: floatation technique enhanced with immunofluorescence is as effective as immunomagnetic separation method.

    PubMed

    Koompapong, Khuanchai; Sutthikornchai, Chantira; Sukthana, Yowalark

    2009-12-01

    Cryptosporidium can cause gastrointestinal diseases worldwide, consequently posing public health problems and economic burden. Effective techniques for detecting contaminated oocysts in water are important to prevent and control the contamination. Immunomagnetic separation (IMS) method has been widely employed recently due to its efficiency, but, it is costly. Sucrose floatation technique is generally used for separating organisms by using their different specific gravity. It is effective and cheap but time consuming as well as requiring highly skilled personnel. Water turbidity and parasite load in water sample are additional factors affecting to the recovery rate of those 2 methods. We compared the efficiency of IMS and sucrose floatation methods to recover the spiked Cryptosporidium oocysts in various turbidity water samples. Cryptosporidium oocysts concentration at 1, 10(1), 10(2), and 10(3) per 10 microl were spiked into 3 sets of 10 ml-water turbidity (5, 50, and 500 NTU). The recovery rate of the 2 methods was not different. Oocyst load at the concentration < 10(2) per 10 ml yielded unreliable results. Water turbidity at 500 NTU decreased the recovery rate of both techniques. The combination of sucrose floatation and immunofluorescense assay techniques (SF-FA) showed higher recovery rate than IMS and immunofluorescense assay (IMS-FA). We used this SF-FA to detect Cryptosporidium and Giardia from the river water samples and found 9 and 19 out of 30 (30% and 63.3%) positive, respectively. Our results favored sucrose floatation technique enhanced with immunofluorescense assay for detecting contaminated protozoa in water samples in general laboratories and in the real practical setting.

  10. High frequency sampling of stable water isotopes for assessing runoff generation processes in a mesoscale urbanized catchment

    NASA Astrophysics Data System (ADS)

    Wrede, Sebastian; Fenicia, Fabrizio; Kurtenbach, Andreas; Keßler, Sabine; Bierl, Reinhard

    2013-04-01

    Experimental hydrology critically relies on tracer techniques to decipher and uncover runoff generation processes. Although tracer measurements contributed significantly to a better understanding of catchment functioning, their potential is not yet fully exploited. The temporal resolution of tracer measurements is typically relatively coarse, and applications are confined to a few locations. Additionally, experimental hydrology has focused primarily on pristine catchments, and the influence of anthropogenic effects remains largely unexplored. High frequency sampling of multiple tracers may therefore substantially enhance our understanding of hydrological processes and the impact of anthropogenic effects and enable a better protection and management of water resources and water quality. In this preliminary study we aim to assess runoff generation processes using geochemical and isotopic tracer techniques in the mesoscale Olewiger Bach catchment (24 km²) that is located in the low mountain ranges of the city of Trier, southwest Germany. The catchment is mainly characterized by quartzite and Devonian schist, overlain by fluvial sediments. Mixed land use prevails in the southern part of the basin, while the northern lower reaches are mainly urbanized. Several waste water treatment plants, separate sewer and stormwater management systems are present in parts of the catchment and contribute to the discharge of the main river. Tracer techniques employed in this ongoing study are twofold. A long term sampling of stable water isotopes (oxygen-18 and deuterium) was initiated in order to allow inferences about mean residence times of water in different catchment compartments, while event-based sampling using a multi-tracer approach was used to identify different runoff components and associated water pathways. Special attention is given to the observation of in-channel processes by assessing the dynamics of dissolved and particulate geochemical tracers and stable water

  11. ADDITIONAL STRESS AND FRACTURE MECHANICS ANALYSES OF PRESSURIZED WATER REACTOR PRESSURE VESSEL NOZZLES

    SciTech Connect

    Walter, Matthew; Yin, Shengjun; Stevens, Gary; Sommerville, Daniel; Palm, Nathan; Heinecke, Carol

    2012-01-01

    In past years, the authors have undertaken various studies of nozzles in both boiling water reactors (BWRs) and pressurized water reactors (PWRs) located in the reactor pressure vessel (RPV) adjacent to the core beltline region. Those studies described stress and fracture mechanics analyses performed to assess various RPV nozzle geometries, which were selected based on their proximity to the core beltline region, i.e., those nozzle configurations that are located close enough to the core region such that they may receive sufficient fluence prior to end-of-life (EOL) to require evaluation of embrittlement as part of the RPV analyses associated with pressure-temperature (P-T) limits. In this paper, additional stress and fracture analyses are summarized that were performed for additional PWR nozzles with the following objectives: To expand the population of PWR nozzle configurations evaluated, which was limited in the previous work to just two nozzles (one inlet and one outlet nozzle). To model and understand differences in stress results obtained for an internal pressure load case using a two-dimensional (2-D) axi-symmetric finite element model (FEM) vs. a three-dimensional (3-D) FEM for these PWR nozzles. In particular, the ovalization (stress concentration) effect of two intersecting cylinders, which is typical of RPV nozzle configurations, was investigated. To investigate the applicability of previously recommended linear elastic fracture mechanics (LEFM) hand solutions for calculating the Mode I stress intensity factor for a postulated nozzle corner crack for pressure loading for these PWR nozzles. These analyses were performed to further expand earlier work completed to support potential revision and refinement of Title 10 to the U.S. Code of Federal Regulations (CFR), Part 50, Appendix G, Fracture Toughness Requirements, and are intended to supplement similar evaluation of nozzles presented at the 2008, 2009, and 2011 Pressure Vessels and Piping (PVP

  12. Fermentation Quality of Ensiled Water Hyacinth (Eichhornia crassipes) as Affected by Additives.

    PubMed

    Tham, Ho Thanh; Van Man, Ngo; Pauly, Thomas

    2013-02-01

    A lab-scale ensiling study was carried out to investigate the fermentation quality of water hyacinth (WH) supplemented with molasses, rice bran, as an absorbent, and an inoculant in the form of fermented vegetable juice and their combinations. After wilting the water hyacinths for 7 h to a dry matter (DM) content of 240 to 250 g/kg, the following treatments were applied: i) Control (C), WH only; ii) WH with sugarcane molasses at 40 g/kg WH (CM); iii) WH inoculated with fermented vegetable juice at 10 ml/kg WH (CI); iv) CM and CI (CMI) combined; v) WH with 150 g rice bran/kg WH (CA); vi) CA and CI combined (CAI); vii) CA and CM combined (CAM); and viii) CA, CM and CI combined (CAMI). After application of additives, the differently treated forages were mixed and ensiled in triplicates in 1,500-ml polyethylene jars. After ensiling for 3 d, pH values in all treatments, except C and CI, had decreased to approximately 4.0 and remained low till 14 d. After 56 d, pH had increased between 0.4 to 0.9 pH-units compared to those at 14 d. The ammonia nitrogen (NH3-N) concentration ranged from an acceptable level in treatment CM (8 g/kg N) to a high NH3-N value in treatment CMI (16 g/kg N). Lactic acid formation was higher in CI than in all other treatments. Butyric acid contents, which indicate badly fermented silages, were low in all silages (<2 g/kg DM). There were two-way interactions (p-values from <0.001 to 0.045) for almost all fermentation end-products and pH, except for the molasses×inoculant interaction on NH3-N (p = 0.26). Significant 3-way interactions were found on all observed variables except for weight losses of silages. It is concluded that conserving wilted WH as silage for ruminants may be improved by the addition of molasses or rice bran.

  13. Fermentation Quality of Ensiled Water Hyacinth (Eichhornia crassipes) as Affected by Additives

    PubMed Central

    Tham, Ho Thanh; Van Man, Ngo; Pauly, Thomas

    2013-01-01

    A lab-scale ensiling study was carried out to investigate the fermentation quality of water hyacinth (WH) supplemented with molasses, rice bran, as an absorbent, and an inoculant in the form of fermented vegetable juice and their combinations. After wilting the water hyacinths for 7 h to a dry matter (DM) content of 240 to 250 g/kg, the following treatments were applied: i) Control (C), WH only; ii) WH with sugarcane molasses at 40 g/kg WH (CM); iii) WH inoculated with fermented vegetable juice at 10 ml/kg WH (CI); iv) CM and CI (CMI) combined; v) WH with 150 g rice bran/kg WH (CA); vi) CA and CI combined (CAI); vii) CA and CM combined (CAM); and viii) CA, CM and CI combined (CAMI). After application of additives, the differently treated forages were mixed and ensiled in triplicates in 1,500-ml polyethylene jars. After ensiling for 3 d, pH values in all treatments, except C and CI, had decreased to approximately 4.0 and remained low till 14 d. After 56 d, pH had increased between 0.4 to 0.9 pH-units compared to those at 14 d. The ammonia nitrogen (NH3-N) concentration ranged from an acceptable level in treatment CM (8 g/kg N) to a high NH3-N value in treatment CMI (16 g/kg N). Lactic acid formation was higher in CI than in all other treatments. Butyric acid contents, which indicate badly fermented silages, were low in all silages (<2 g/kg DM). There were two-way interactions (p-values from <0.001 to 0.045) for almost all fermentation end-products and pH, except for the molasses×inoculant interaction on NH3-N (p = 0.26). Significant 3-way interactions were found on all observed variables except for weight losses of silages. It is concluded that conserving wilted WH as silage for ruminants may be improved by the addition of molasses or rice bran. PMID:25049776

  14. Natural cotton fibers as adsorbent for solid-phase extraction of polycyclic aromatic hydrocarbons in water samples.

    PubMed

    Wang, Jianping; Liu, Shengquan; Chen, Chunyan; Zou, Ying; Hu, Huiping; Cai, Qingyun; Yao, Shouzhuo

    2014-07-21

    A natural material, cotton fiber, has been applied as a solid-phase extraction (SPE) adsorbent for sample preparation for the analysis of polycyclic aromatic hydrocarbons (PAH) in water samples using high-performance liquid chromatography. The cotton fiber was used directly without any chemical modifications, which avoided a complex synthesis process and consumption of a large volume of organic solvent. The conditions affecting the extraction efficiency were optimized to achieve high detection sensitivity, and included elution solvent, ultrasonic elution time, extraction time, sample volume, salt concentration and organic modifier addition. Under the optimal conditions, the detection limits for seven PAH compounds could reach up to 0.1-2.0 ng L(-1). The method accuracy was evaluated using recovery measurements in standard spiked samples and good recoveries of 70.69-110.04% with relative standard deviations of less than 10% have been achieved. Consequently, the method developed was successfully applied for determining PAH in environmental samples: snow water, metal-fabrication factory wastewater and Xiangjiang River water, with PAH contents ranging from 13.2 to 83.1 ng L(-1). Therefore, using cotton fiber as a new SPE adsorbent, was easy to prepare, had a low cost and great reusability, and this implies it is a promising method for sample preparation.

  15. Monitoring-well network and sampling design for ground-water quality, Wind River Indian Reservation, Wyoming

    USGS Publications Warehouse

    Mason, Jon P.; Sebree, Sonja K.; Quinn, Thomas L.

    2005-01-01

    The Wind River Indian Reservation, located in parts of Fremont and Hot Springs Counties, Wyoming, has a total land area of more than 3,500 square miles. Ground water on the Wind River Indian Reservation is a valuable resource for Shoshone and Northern Arapahoe tribal members and others who live on the Reservation. There are many types of land uses on the Reservation that have the potential to affect the quality of ground-water resources. Urban areas, rural housing developments, agricultural lands, landfills, oil and natural gas fields, mining, and pipeline utility corridors all have the potential to affect ground-water quality. A cooperative study was developed between the U.S. Geological Survey and the Wind River Environmental Quality Commission to identify areas of the Reservation that have the highest potential for ground-water contamination and develop a comprehensive plan to monitor these areas. An arithmetic overlay model for the Wind River Indian Reservation was created using seven geographic information system data layers representing factors with varying potential to affect ground-water quality. The data layers used were: the National Land Cover Dataset, water well density, aquifer sensitivity, oil and natural gas fields and petroleum pipelines, sites with potential contaminant sources, sites that are known to have ground-water contamination, and National Pollutant Discharge Elimination System sites. A prioritization map for monitoring ground-water quality on the Reservation was created using the model. The prioritization map ranks the priority for monitoring ground-water quality in different areas of the Reservation as low, medium, or high. To help minimize bias in selecting sites for a monitoring well network, an automated stratified random site-selection approach was used to select 30 sites for ground-water quality monitoring within the high priority areas. In addition, the study also provided a sampling design for constituents to be monitored, sampling

  16. Instrumental neutron activation analysis data for cloud-water particulate samples, Mount Bamboo, Taiwan

    USGS Publications Warehouse

    Lin, Neng-Huei; Sheu, Guey-Rong; Wetherbee, Gregory A.; Debey, Timothy M.

    2013-01-01

    Cloud water was sampled on Mount Bamboo in northern Taiwan during March 22-24, 2002. Cloud-water samples were filtered using 0.45-micron filters to remove particulate material from the water samples. Filtered particulates were analyzed by instrumental neutron activation analysis (INAA) at the U.S. Geological Survey National Reactor Facility in Denver, Colorado, in February 2012. INAA elemental composition data for the particulate materials are presented. These data complement analyses of the aqueous portion of the cloud-water samples, which were performed earlier by the Department of Atmospheric Sciences, National Central University, Taiwan. The data are intended for evaluation of atmospheric transport processes and air-pollution sources in Southeast Asia.

  17. Vacuum hand pump apparatus for collecting water samples from a horizontal intragravel pipe

    USGS Publications Warehouse

    Saiki, Michael K.; Martin, Barbara A.

    1996-01-01

    We describe a lightweight, portable vacuum hand pump apparatus for use in collecting water samples from horizontal intragravel pipe samplers buried in the stream bottom. The apparatus is easily fabricated from relatively inexpensive materials available at many laboratory supply houses.

  18. A new experimental design for laser-driven shocks on precompressed and preheated water samples

    SciTech Connect

    Sollier, A.; Auroux, E.; Vauthier, J.-S.; Desbiens, N.; Bourasseau, E.; Maillet, J.-B.; Boustie, M.; He, H.; Resseguier, T. de; Berterretche, P.

    2007-12-12

    Laser driven shock measurements have been performed on precompressed and preheated water samples in order to reach states lying above the standard water Hugoniot in the pressure versus temperature diagram, which are representative of the thermodynamic parameters of water in the detonation products of high condensed explosives. In this experimental system, water is used as both target sample and window medium for VISAR diagnosis. We report the first experiments performed with the LCD's laser system at low shock pressure, on water samples preheated up to 300 deg. C and precompressed up to 300 bar. The results are used to check the predictions of the CARTE thermochemical code, and compared with the Sesame equation of state and with molecular Monte Carlo calculations.

  19. GROUND WATER ISSUE: LOW-FLOW (MINIMAL DRAWDOWN) GROUND-WATER SAMPLING PROCEDURES

    EPA Science Inventory

    This paper is intended to provide background information on the development of low-flow sampling procedures and its application under a variety of hydrogeologic settings. The sampling methodology described in this paper assumes that the monitoring goal is to sample monitoring wel...

  20. Exploring the Legionella pneumophila positivity rate in hotel water samples from Antalya, Turkey.

    PubMed

    Sepin Özen, Nevgün; Tuğlu Ataman, Şenay; Emek, Mestan

    2017-03-29

    The genus Legionella is a fastidious Gram-negative bacteria widely distributed in natural waters and man made water supply systems. Legionella pneumophila is the aetiological agent of approximately 90% of reported Legionellosis cases, and serogroup 1 is the most frequent cause of infections. Legionnaires' disease is often associated with travel and continues to be a public health concern at present. The correct water management quality practices and rapid methods for analyzing Legionella species in environmental water is a key point for the prevention of Legionnaires' disease outbreaks. This study aimed to evaluate the positivity rates and serotyping of Legionella species from water samples in the region of Antalya, Turkey, which is an important tourism center. During January-December 2010, a total of 1403 samples of water that were collected from various hotels (n = 56) located in Antalya were investigated for Legionella pneumophila. All samples were screened for L. pneumophila by culture method according to "ISO 11731-2" criteria. The culture positive Legionella strains were serologically identified by latex agglutination test. A total of 142 Legionella pneumophila isolates were recovered from 21 (37.5%) of 56 hotels. The total frequency of L. pneumophila isolation from water samples was found as 10.1%. Serological typing of 142 Legionella isolates by latex agglutination test revealed that strains belonging to L. pneumophila serogroups 2-14 predominated in the examined samples (85%), while strains of L. pneumophila serogroup 1 were less numerous (15%). According to our knowledge, our study with the greatest number of water samples from Turkey demonstrates that L. pneumophila serogroups 2-14 is the most common isolate. Rapid isolation of L. pneumophila from environmental water samples is essential for the investigation of travel related outbreaks and the possible resources. Further studies are needed to have epidemiological data and to determine the types of L

  1. Atrazine, triketone herbicides, and their degradation products in sediment, soil and surface water samples in Poland.

    PubMed

    Barchanska, Hanna; Sajdak, Marcin; Szczypka, Kornelia; Swientek, Angelika; Tworek, Martyna; Kurek, Magdalena

    2017-01-01

    The aim of this study was to monitor the sediment, soil and surface water contamination with selected popular triketone herbicides (mesotrione (MES) and sulcotrione(SUL)), atrazine (ATR) classified as a possible carcinogen and endocrine disrupting chemical, as well as their degradation products, in Silesia (Poland). Seventeen sediment samples, 24 soil samples, and 64 surface water samples collected in 2014 were studied. After solid-liquid extraction (SLE) and solid phase extraction (SPE), analytes were determined by high-performance liquid chromatography (HPLC) with diode array detection (DAD). Ten years after the withdrawal from the use, ATR was not detected in any of the collected samples; however, its degradation products are still present in 41 % of sediment, 71 % of soil, and 8 % of surface water samples. SUL was determined in 85 % of soil samples; its degradation product (2-chloro-4-(methylosulfonyl) benzoic acid (CMBA)) was present in 43 % of soil samples. In 17 % of sediment samples, CMBA was detected. Triketones were detected occasionally in surface water samples. The chemometric analysis (clustering analysis (CA), single-factor analysis of variance (ANOVA), N-Way ANOVA) was applied to find relations between selected soil and sediment parameters and herbicides concentration. In neither of the studied cases a statistically significant relationship between the concentrations of examined herbicides, their degradation products and soil parameters (organic carbon (OC), pH) was observed.

  2. EPA Proposes Additional Water Line Connections for Groundwater Contamination at Tinkham Garage Superfund Site in Londonderry, NH

    EPA Pesticide Factsheets

    The U.S. EPA in consultation with NHDES, is proposing additional connections to an existing water line for residents whose wells have been found to have contamination and whom live northeast section of the Tinkham Garage Superfund Site (Site).

  3. Rapid screening of 90Sr activity in water and milk samples using Cherenkov radiation.

    PubMed

    Stamoulis, K C; Ioannides, K G; Karamanis, D T; Patiris, D C

    2007-01-01

    A method for screening 90Sr in milk samples is proposed. This method is based on a liquid scintillation technique taking advantage of Cherenkov radiation, which is produced in a liquid medium and then detected by the photomultipliers of a Liquid Scintillation Counter (LSC). Twenty millilitres of water and milk samples spiked with various concentrations of 90Sr/90Y in equilibrium were added in plastic vials and then were measured with an LSC (TriCarb 3170 TR/SL). The derived efficiencies were 49% for water samples and 14% for milk samples. The detection limit was 470 mBq L(-1)(90)Sr for water, without any pretreatment. Milk contains potassium, which also produces Cherenkov radiation due to the presence of 40K. For this reason, the interference of 40K in the measurements of 90Sr in milk samples was also investigated. The detection limit for milk was 1.7 Bq L(-1)90Sr.

  4. UMTRA project water sampling and analysis plan, Naturita, Colorado. Revision 1

    SciTech Connect

    1995-09-01

    Planned, routine ground water sampling activities for calendar year 1995 to 1997 at the US Department of Energy (DOE) Uranium Mill Tailings Remedial Action (UMTRA) Project site near Naturita, Colorado, are described in this water sampling and analysis plan. The following plan identifies and justifies the sampling locations, analytical parameters, detection limits, sampling frequency, and specific rationale for each routine monitoring station at the site. The regulatory basis for routine ground water monitoring at UMTRA Project sites is derived from the US Environmental Protection Agency (EPA) regulations in 40 CFR Part 192. Sampling procedures are guided by the UMTRA Project standard operating procedures (SOP) (JEG, n.d.), the Technical Approach Document (TAD) (DOE, 1989), and the most effective technical approach for the site.

  5. Hepatitis A virus in environmental water samples from the Amazon Basin.

    PubMed

    De Paula, V S; Diniz-Mendes, L; Villar, L M; Luz, S L B; Silva, L A; Jesus, M S; da Silva, N M V S; Gaspar, A M C

    2007-03-01

    Hepatitis A virus (HAV) is a significant waterborne human pathogen. Of the global supply of potable water, Brazil retains 13%, of which 75% resides in the Amazon Basin. Although hepatitis A morbidity has declined progressively in Brazil as a whole, it remains high in the Amazon region. We used nested and real-time reverse-transcription polymerase chain reaction (RT-PCR) to detect and quantify the viral load in water samples from the Amazon Basin. Most samples tested positive (92%), with viral loads varying from 60 to 5500 copies /L, depending on sanitary conditions and the degree of flooding. Nested RT-PCR of the VP1-2A region detected HAV RNA in 23% of the samples. In low viral load samples, HAV was detected only with real-time RT-PCR, suggesting that this technique is useful for monitoring HAV contamination. The presence of HAV in water samples constitutes a serious public health problem.

  6. Soy Protein Isolate As Fluid Loss Additive in Bentonite-Water-Based Drilling Fluids.

    PubMed

    Li, Mei-Chun; Wu, Qinglin; Song, Kunlin; Lee, Sunyoung; Jin, Chunde; Ren, Suxia; Lei, Tingzhou

    2015-11-11

    Wellbore instability and formation collapse caused by lost circulation are vital issues during well excavation in the oil industry. This study reports the novel utilization of soy protein isolate (SPI) as fluid loss additive in bentonite-water based drilling fluids (BT-WDFs) and describes how its particle size and concentration influence on the filtration property of SPI/BT-WDFs. It was found that high pressure homogenization (HPH)-treated SPI had superior filtration property over that of native SPI due to the improved ability for the plugging pore throat. HPH treatment also caused a significant change in the surface characteristic of SPI, leading to a considerable surface interaction with BT in aqueous solution. The concentration of SPI had a significant impact on the dispersion state of SPI/BT mixtures in aquesous solution. At low SPI concentrations, strong aggregations were created, resulting in the formation of thick, loose, high-porosity and high-permeability filter cakes and high fluid loss. At high SPI concentrations, intercatlated/exfoliated structures were generated, resulting in the formation of thin, compact, low-porosity and low-permeability filter cakes and low fluid loss. The SPI/BT-WDFs exhibited superior filtration property than pure BT-WDFs at the same solid concentraion, demonstrating the potential utilization of SPI as an effective, renewable, and biodegradable fluid loss reducer in well excavation applications.

  7. Slug tests in wells screened across the water table: some additional considerations.

    PubMed

    Butler, J J

    2014-01-01

    The majority of slug tests done at sites of shallow groundwater contamination are performed in wells screened across the water table and are affected by mechanisms beyond those considered in the standard slug-test models. These additional mechanisms give rise to a number of practical issues that are yet to be fully resolved; four of these are addressed here. The wells in which slug tests are performed were rarely installed for that purpose, so the well design can result in problematic (small signal to noise ratio) test data. The suitability of a particular well design should thus always be assessed prior to field testing. In slug tests of short duration, it can be difficult to identify which portion of the test represents filter-pack drainage and which represents formation response; application of a mass balance can help confirm that test phases have been correctly identified. A key parameter required for all slug test models is the casing radius. However, in this setting, the effective casing radius (borehole radius corrected for filter-pack porosity), not the nominal well radius, is required; this effective radius is best estimated directly from test data. Finally, although conventional slug-test models do not consider filter-pack drainage, these models will yield reasonable hydraulic conductivity estimates when applied to the formation-response phase of a test from an appropriately developed well.

  8. Evaluation of free water and water activity measurements as functional alternatives to total moisture content in broiler excreta and litter samples.

    PubMed

    van der Hoeven-Hangoor, E; Rademaker, C J; Paton, N D; Verstegen, M W A; Hendriks, W H

    2014-07-01

    Litter moisture contents vary greatly between and within practical poultry barns. The current experiment was designed to measure the effects of 8 different dietary characteristics on litter and excreta moisture content. Additionally, free water content and water activity of the excreta and litter were evaluated as additional quality measures. The dietary treatments consisted of nonstarch polysaccharide content (NSP; corn vs. wheat), particle size of insoluble fiber (coarse vs. finely ground oat hulls), viscosity of a nonfermentable fiber (low- and high-viscosity carboxymethyl cellulose), inclusion of a clay mineral (sepiolite), and inclusion of a laxative electrolyte (MgSO4). The 8 treatments were randomly assigned to cages within blocks, resulting in 12 replicates per treatment with 6 birds per replicate. Limited effects of the dietary treatments were noted on excreta and litter water activity, and indications were observed that this measurement is limited in high-moisture samples. Increasing dietary NSP content by feeding a corn-based diet (low NSP) compared with a wheat-based diet (high NSP) increased water intake, excreta moisture and free water, and litter moisture content. Adding insoluble fibers to the wheat-based diet reduced excreta and litter moisture content, as well as litter water activity. Fine grinding of the oat hulls diminished the effect on litter moisture and water activity. However, excreta moisture and free water content were similar when fed finely or coarsely ground oat hulls. The effects of changing viscosity and adding a clay mineral or laxative deviated from results observed in previous studies. Findings of the current experiment indicate a potential for excreta free water measurement as an additional parameter to assess excreta quality besides total moisture. The exact implication of this parameter warrants further investigation.

  9. An immunomagnetic separation-real-time PCR method for quantification of Cryptosporidium parvum in water samples.

    PubMed

    Fontaine, Melanie; Guillot, Emmanuelle

    2003-07-01

    The protozoan parasite Cryptosporidium parvum is known to occur widely in both raw and drinking water and is the cause of waterborne outbreaks of gastroenteritis throughout the world. The routinely used method for the detection of Cryptosporidium oocysts in water is based on an immunofluorescence assay (IFA). It is both time-consuming and nonspecific for the human pathogenic species C. parvum. We have developed a TaqMan polymerase chain reaction (PCR) test that accurately quantifies C. parvum oocysts in treated and untreated water samples. The protocol consisted of the following successive steps: Envirochek capsule filtration, immunomagnetic separation (IMS), thermal lysis followed by DNA purification using Nanosep centrifugal devices and, finally, real-time PCR using fluorescent TaqMan technology. Quantification was accomplished by comparing the fluorescence signals obtained from test samples with those from standard dilutions of C. parvum oocysts. This IMS-real-time PCR assay permits rapid and reliable quantification over six orders of magnitude, with a detection limit of five oocysts for purified oocyst solutions and eight oocysts for spiked water samples. Replicate samples of spiked tap water and Seine River water samples (with approximately 78 and 775 oocysts) were tested. C. parvum oocyst recoveries, which ranged from 47.4% to 99% and from 39.1% to 68.3%, respectively, were significantly higher and less variable than those reported using the traditional US Environmental Protection Agency (USEPA) method 1622. This new molecular method offers a rapid, sensitive and specific alternative for C. parvum oocyst quantification in water.

  10. Water quality in dental chair units. A random sample in the canton of St. Gallen.

    PubMed

    Barben, Jürg; Kuehni, Claudia E; Schmid, Jürg

    2009-01-01

    This study aimed to identify the microbial contamination of water from dental chair units (DCUs) using the prevalence of Pseudomonas aeruginosa, Legionella species and heterotrophic bacteria as a marker of pollution in water in the area of St. Gallen, Switzerland. Water (250 ml) from 76 DCUs was collected twice (early on a morning before using all the instruments and after using the DCUs for at least two hours) either from the high-speed handpiece tube, the 3 in 1 syringe or the micromotor for water quality testing. An increased bacterial count (>300 CFU/ml) was found in 46 (61%) samples taken before use of the DCU, but only in 29 (38%) samples taken two hours after use. Pseudomonas aeruginosa was found in both water samples in 6/76 (8%) of the DCUs. Legionella were found in both samples in 15 (20%) of the DCUs tested. Legionella anisa was identified in seven samples and Legionella pneumophila was found in eight. DCUs which were less than five years old were contaminated less often than older units (25% und 77%, p<0.001). This difference remained significant (0=0.0004) when adjusted for manufacturer and sampling location in a multivariable logistic regression. A large proportion of the DCUs tested did not comply with the Swiss drinking water standards nor with the recommendations of the American Centers for Disease Control and Prevention (CDC).

  11. Preparations and properties of anti-corrosion additives of water-soluble metal working fluids for aluminum alloy materials.

    PubMed

    Watanabe, Shoji

    2008-01-01

    This short review describes various types of anti-corrosion additives of water-soluble metal working fluids for aluminum alloy materials. It is concerned with synthetic additives classified according to their functional groups; silicone compounds, carboxylic acids and dibasic acids, esters, Diels-Alder adducts, various polymers, nitrogen compounds, phosphoric esters, phosphonic acids, and others. Testing methods for water-soluble metal working fluids for aluminum alloy materials are described for a practical application in a laboratory.

  12. 78 FR 56695 - Proposed Listing of Additional Waters To Be Included on Indiana's 2010 List of Impaired Waters...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-13

    ... EPA's proposed decision identifying water quality limited segments and associated pollutants in Indiana to be listed pursuant to the Clean Water Act Section 303(d)(2), and requests public comment. For... Under the Clean Water Act AGENCY: Environmental Protection Agency (EPA). ACTION: Reopening of...

  13. 78 FR 35929 - Proposed Listing of Additional Waters To Be Included on Indiana's 2010 List of Impaired Waters...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-14

    ... decision identifying water quality limited segments and associated pollutants in Indiana to be listed... pollution controls are not stringent enough to attain or maintain state water quality standards and for... certain water quality limited segments and associated pollutants (Table 1 in Appendix A1 of EPA's...

  14. A Novel Lipase as Aquafeed Additive for Warm-Water Aquaculture

    PubMed Central

    Yang, Yalin; Huang, Lu; Zhou, Zhigang

    2015-01-01

    A novel Acinetobacter lipase gene lipG1was cloned from DNA extracted from intestinal sample of common carp (Cyprinus carpio), and expressed in E. coli BL21. The encoded protein was 406 amino acids in length. Phylogenetic analysis indicated that LipG1 and its relatives comprised a novel group of true lipases produced by Gram-negative bacteria. LipG1 showed maximal activity at 40℃ and pH 8.0 when pNP decanoate (C10) was used as the substrate, and remained high activity between 20℃ and 35℃. Activity of the lipase was promoted by Ca2+ and Mg2+, and inhibited by Zn2+ and Cu2+. Moreover, LipG1 is stable with proteases, most commercial detergents and organic solvents. Substrate specificity test indicated that LipG1can hydrolyse pNP esters with acyl chain length from C2 to C16, with preference for medium-chain pNP esters (C8, C10). Lastly, LipG1was evaluated as an aquafeed additive for juvenile common carp (Cyprinus carpio). Results showed that supplementation of LipG1significantly improved the gut and heptaopancreas lipase activity of fish fed with palm oil diet. Consistently, improved feed conversion ratio and growth performance were recorded in the LipG1 feeding group, to levels comparable to the group of fish fed with soybean oil diet. Collectively, LipG1 exhibited good potential as an aquafeed additive enzyme, and deserves further characterization as the representative of a novel group of lipases. PMID:26147311

  15. A Novel Lipase as Aquafeed Additive for Warm-Water Aquaculture.

    PubMed

    Ran, Chao; He, Suxu; Yang, Yalin; Huang, Lu; Zhou, Zhigang

    2015-01-01

    A novel Acinetobacter lipase gene lipG1 was cloned from DNA extracted from intestinal sample of common carp (Cyprinus carpio), and expressed in E. coli BL21. The encoded protein was 406 amino acids in length. Phylogenetic analysis indicated that LipG1 and its relatives comprised a novel group of true lipases produced by Gram-negative bacteria. LipG1 showed maximal activity at 40℃ and pH 8.0 when pNP decanoate (C10) was used as the substrate, and remained high activity between 20℃ and 35℃. Activity of the lipase was promoted by Ca2+ and Mg2+, and inhibited by Zn2+ and Cu2+. Moreover, LipG1 is stable with proteases, most commercial detergents and organic solvents. Substrate specificity test indicated that LipG1 can hydrolyse pNP esters with acyl chain length from C2 to C16, with preference for medium-chain pNP esters (C8, C10). Lastly, LipG1 was evaluated as an aquafeed additive for juvenile common carp (Cyprinus carpio). Results showed that supplementation of LipG1 significantly improved the gut and heptaopancreas lipase activity of fish fed with palm oil diet. Consistently, improved feed conversion ratio and growth performance were recorded in the LipG1 feeding group, to levels comparable to the group of fish fed with soybean oil diet. Collectively, LipG1 exhibited good potential as an aquafeed additive enzyme, and deserves further characterization as the representative of a novel group of lipases.

  16. Ground-water quality in east-central New Jersey and a plan for sampling networks

    SciTech Connect

    Harriman, D.A.; Sargent, B.P.

    1985-01-01

    Groundwater quality was evaluated in seven confined aquifers and the water table aquifer in east-central New Jersey based on 237 analyses of samples collected in 1981-82, and 225 older analyses. Investigation of the effect of land use on water quality and several sampling network proposals for the region are reported. Iron (Fe) and manganese (Mn) concentrations exceed US EPA drinking water standards in some wells screened in the Potomac-Raritan-Magothy aquifer system. Sodium (Na) concentrations in samples from three wells more than 800 ft deep in the Englishtown aquifer exceed the standard. Iron and Mn concentrations in this aquifer may also exceed the standards. Iron concentrations in the Wenonah-Mount Laurel aquifer exceed the standard. Based on 15 analyses of water from the Vincetown aquifer, Mn is the only constituent that exceeds the drinking water standard. In the Manasquan aquifer, 4 of the 16 Na determinations exceed the standard, and 8 of 16 Fe determinations exceed the standard. Water quality in the Atlantic City 800-ft sand is generally satisfactory. However, 12 Fe and 1 of 12 Mn determinations exceed the standards. For the Rio Grande water-bearing zone, 1 of 3 Fe determinations exceed the standard. The Kirkwood-Cohansey aquifer system was the most thoroughly sampled (249 chemical analyses from 209 wells). Dissolved solids, chloride, Fe, nitrate, and Mn concentrations exceed drinking water standards in some areas. 76 refs., 36 figs., 12 tabs.

  17. Natural radioactivity in various water samples and radiation dose estimations in Bolu province, Turkey.

    PubMed

    Gorur, F Korkmaz; Camgoz, H

    2014-10-01

    The level of natural radioactivity for Bolu province of north-western Turkey was assessed in this study. There is no information about radioactivity measurement reported in water samples in the Bolu province so far. For this reason, gross α and β activities of 55 different water samples collected from tap, spring, mineral, river and lake waters in Bolu were determined. The mean activity concentrations were 68.11 mBq L(-1), 169.44 mBq L(-1) for gross α and β in tap water. For all samples the gross β activity is always higher than the gross α activity. All value of the gross α were lower than the limit value of 500 mBq L(-1) while two spring and one mineral water samples were found to have gross β activity concentrations of greater than 1000 mBq L(-1). The associated age-dependent dose from all water ingestion in Bolu was estimated. The total dose for adults had an average value exceeds the WHO recommended limit value. The risk levels from the direct ingestion of the natural radionuclides in tap and mineral water in Bolu were determinated. The mean (210)Po and (228)Ra risk the value of tap and mineral waters slightly exceeds what some consider on acceptable risk of 10(-4) or less.

  18. Soil and Water – What is Detectable through Microbiological Sample Preparation Techniques

    EPA Science Inventory

    The concerns of a potential terrorist’s use of biological agents in soil and ground water are articulated by comparisons to major illnesses in this Country involving contaminated drinking water sources. Objectives are focused on the importance of sample preparation in the rapid, ...

  19. Comparison of water-quality samples collected by siphon samplers and automatic samplers in Wisconsin

    USGS Publications Warehouse

    Graczyk, David J.; Robertson, Dale M.; Rose, William J.; Steur, Jeffrey J.

    2000-01-01

    In small streams, flow and water-quality concentrations often change quickly in response to meteorological events. Hydrologists, field technicians, or locally hired stream ob- servers involved in water-data collection are often unable to reach streams quickly enough to observe or measure these rapid changes. Therefore, in hydrologic studies designed to describe changes in water quality, a combination of manual and automated sampling methods have commonly been used manual methods when flow is relatively stable and automated methods when flow is rapidly changing. Auto- mated sampling, which makes use of equipment programmed to collect samples in response to changes in stage and flow of a stream, has been shown to be an effective method of sampling to describe the rapid changes in water quality (Graczyk and others, 1993). Because of the high cost of automated sampling, however, especially for studies examining a large number of sites, alternative methods have been considered for collecting samples during rapidly changing stream conditions. One such method employs the siphon sampler (fig. 1). also referred to as the "single-stage sampler." Siphon samplers are inexpensive to build (about $25- $50 per sampler), operate, and maintain, so they are cost effective to use at a large number of sites. Their ability to collect samples representing the average quality of water passing though the entire cross section of a stream, however, has not been fully demonstrated for many types of stream sites.

  20. Classification and authentication of unknown water samples using machine learning algorithms.

    PubMed

    Kundu, Palash K; Panchariya, P C; Kundu, Madhusree

    2011-07-01

    This paper proposes the development of water sample classification and authentication, in real life which is based on machine learning algorithms. The proposed techniques used experimental measurements from a pulse voltametry method which is based on an electronic tongue (E-tongue) instrumentation system with silver and platinum electrodes. E-tongue include arrays of solid state ion sensors, transducers even of different types, data collectors and data analysis tools, all oriented to the classification of liquid samples and authentication of unknown liquid samples. The time series signal and the corresponding raw data represent the measurement from a multi-sensor system. The E-tongue system, implemented in a laboratory environment for 6 numbers of different ISI (Bureau of Indian standard) certified water samples (Aquafina, Bisleri, Kingfisher, Oasis, Dolphin, and McDowell) was the data source for developing two types of machine learning algorithms like classification and regression. A water data set consisting of 6 numbers of sample classes containing 4402 numbers of features were considered. A PCA (principal component analysis) based classification and authentication tool was developed in this study as the machine learning component of the E-tongue system. A proposed partial least squares (PLS) based classifier, which was dedicated as well; to authenticate a specific category of water sample evolved out as an integral part of the E-tongue instrumentation system. The developed PCA and PLS based E-tongue system emancipated an overall encouraging authentication percentage accuracy with their excellent performances for the aforesaid categories of water samples.

  1. Water intoxication presenting as a suspected contaminated urine sample for drug testing.

    PubMed

    Finkel, Kevin W

    2004-06-01

    A patient was evaluated medically after submitting a urine sample for drug screening that was considered inappropriately dilute. Although it was thought that the dilute urine was the result of purposely adding water, the medical evaluation revealed that the patient had chronic water intoxication from a very strict weight loss regimen. The effect of dietary solute intake on water metabolism by the kidneys and the development of hyponatremia are discussed.

  2. THE COMBINED CARCINOGENIC RISK FOR EXPOSURE TO MIXTURES OF DRINKING WATER DISINFECTION BY-PRODUCTS MAY BE LESS THAN ADDITIVE

    EPA Science Inventory

    The Combined Carcinogenic Risk for Exposure to Mixtures of Drinking Water Disinfection By-Products May be Less Than Additive

    Risk assessment methods for chemical mixtures in drinking water are not well defined. Current default risk assessments for chemical mixtures assume...

  3. Spectrophotometric determination of nitrogen dioxide in air and nitrite in water and soil samples

    SciTech Connect

    Pandurangappa, M.; Balasubramanian, N.

    1995-02-01

    A sensitive spectrophotometric method for the determination of nitrogen dioxide in air and nitrite in water and soil samples is described. Nitrogen dioxide in air is fixed as nitrite ion in alkaline sodium arsenite or in triethanolamine absorber solutions. The method is based on the diazo coupling reaction between p-nitro aniline and 1-hydroxy-2-naphthoic acid. The azo dye formed under aqueous condition has an absorption maximum at 585nm and obeys Beer`s law over the range 0-25{mu}g of nitrite. The colour system is stable for 72h. The relative standard deviation is 2.7% for ten determinations at 15{mu}g of nitrite. The dye is extracted with 1:1 isoamyl alcohol-IBMK mixture and stabilisation with methanolic potassium hydroxide showed {lambda}{sub max} at 610nm. It obeys Beer`s law over the range 0-4{mu}g of nitrite. The colour system is stable for 40h in organic phase and the relative standard deviation is 2.5% for ten determinations at 3{mu}g of nitrite. The molar absorptivity of the colour system is 3.68 x 10{sup 4} Lmol{sup {minus}1} cm{sup {minus}1}. The effect of interfering gases and other ions on the determination of nitrite is described. The developed method has been applied for the determination of residual nitrogen dioxide gas present in the laboratory fume cupboard and automobile exhaust gases. In addition, the method has been applied for the determination of nitrite and nitrate in samples like water, soil and radiator coolants.

  4. [Effects of nitrogen and water addition on soil bacterial diversity and community structure in temperate grasslands in northern China].

    PubMed

    Yang, Shan; Li, Xiao-bing; Wang, Ru-zhen; Cai, Jiang-ping; Xu, Zhu-wen; Zhang, Yu-ge; Li, Hui; Jiang, Yong

    2015-03-01

    In this study, we measured the responses of soil bacterial diversity and community structure to nitrogen (N) and water addition in the typical temperate grassland in northern China. Results showed that N addition significantly reduced microbial biomass carbon (MBC) and microbial biomass nitrogen (MBN) under regular precipitation treatment. Similar declined trends of MBC and MBN caused by N addition were also found under increased precipitation condition. Nevertheless, water addition alleviated the inhibition by N addition. N addition exerted no significant effects. on bacterial α-diversity indices, including richness, Shannon diversity and evenness index under regular precipitation condition. Precipitation increment tended to increase bacterial α-diversity, and the diversity indices of each N gradient under regular precipitation were much lower than that of the corresponding N addition rate under increased precipitation. Correlation analysis showed that soil moisture, nitrate (NO3(-)-N) and ammonium (NH4+-N) were significantly negatively correlated with bacterial evenness index, and MBC and MBN had a significant positive correlation with bacterial richness and evenness. Non-metric multidimensional scaling (NMDS) ordination illustrated that the bacterial communities were significantly separated by N addition rates, under both water ambient and water addition treatments. Redundancy analysis (RDA) revealed that soil MBC, MBN, pH and NH4+-N were the key environmental factors for shaping bacterial communities.

  5. Modification of kanamycin-esculin-azide agar to improve selectivity in the enumeration of fecal streptococci from water samples.

    PubMed Central

    Audicana, A; Perales, I; Borrego, J J

    1995-01-01

    Kanamycin-esculin-azide agar was modified by increasing the concentration of sodium azide to 0.4 g liter-1 and replacing kanamycin sulfate with 5 mg of oxolinic acid liter-1. The modification, named oxolinic acid-esculin-azide (OAA) agar, was compared with Slanetz-Bartley and KF agars by using drinking water and seawater samples. The OAA agar showed higher specificity, selectivity, and recovery efficiencies than those obtained by using the other media. In addition, no confirmation of typical colonies was needed when OAA agar was used, which significantly shortens the time of sample processing and increases the accuracy of the method. PMID:8534085

  6. A solid phase extraction-ion chromatography with conductivity detection procedure for determining cationic surfactants in surface water samples.

    PubMed

    Olkowska, Ewa; Polkowska, Żaneta; Namieśnik, Jacek

    2013-11-15

    A new analytical procedure for the simultaneous determination of individual cationic surfactants (alkyl benzyl dimethyl ammonium chlorides) in surface water samples has been developed. We describe this methodology for the first time: it involves the application of solid phase extraction (SPE-for sample preparation) coupled with ion chromatography-conductivity detection (IC-CD-for the final determination). Mean recoveries of analytes between 79% and 93%, and overall method quantification limits in the range from 0.0018 to 0.038 μg/mL for surface water and CRM samples were achieved. The methodology was applied to the determination of individual alkyl benzyl quaternary ammonium compounds in environmental samples (reservoir water) and enables their presence in such types of waters to be confirmed. In addition, it is a simpler, less time-consuming, labour-intensive, avoiding use of toxic chloroform and significantly less expensive methodology than previously described approaches (liquid-liquid extraction coupled with liquid chromatography-mass spectrometry).

  7. An Optimized Method for Quantification of Pathogenic Leptospira in Environmental Water Samples

    PubMed Central

    Riediger, Irina N.; Hoffmaster, Alex R.; Biondo, Alexander W.; Ko, Albert I.; Stoddard, Robyn A.

    2016-01-01

    Leptospirosis is a zoonotic disease usually acquired by contact with water contaminated with urine of infected animals. However, few molecular methods have been used to monitor or quantify pathogenic Leptospira in environmental water samples. Here we optimized a DNA extraction method for the quantification of leptospires using a previously described Taqman-based qPCR method targeting lipL32, a gene unique to and highly conserved in pathogenic Leptospira. QIAamp DNA mini, MO BIO PowerWater DNA and PowerSoil DNA Isolation kits were evaluated to extract DNA from sewage, pond, river and ultrapure water samples spiked with leptospires. Performance of each kit varied with sample type. Sample processing methods were further evaluated and optimized using the PowerSoil DNA kit due to its performance on turbid water samples and reproducibility. Centrifugation speeds, water volumes and use of Escherichia coli as a carrier were compared to improve DNA recovery. All matrices showed a strong linearity in a range of concentrations from 106 to 10° leptospires/mL and lower limits of detection ranging from <1 cell /ml for river water to 36 cells/mL for ultrapure water with E. coli as a carrier. In conclusion, we optimized a method to quantify pathogenic Leptospira in environmental waters (river, pond and sewage) which consists of the concentration of 40 mL samples by centrifugation at 15,000×g for 20 minutes at 4°C, followed by DNA extraction with the PowerSoil DNA Isolation kit. Although the method described herein needs to be validated in environmental studies, it potentially provides the opportunity for effective, timely and sensitive assessment of environmental leptospiral burden. PMID:27487084

  8. Evaluation of the Validity of Groundwater Samples Obtained Using the Purge Water Management System at SRS

    SciTech Connect

    Beardsley, C.C.

    1999-04-27

    As part of the demonstration testing of the Purge Water Management System (PWMS) technology at the Savannah River Site (SRS), four wells were equipped with PWMS units in 1997 and a series of sampling events were conducted at each during 1997-1998. Three of the wells were located in A/M Area while the fourth was located at the Old Radioactive Waste Burial Ground in the General Separations Area.The PWMS is a ''closed-loop'', non-contact, system used to collect and return purge water to the originating aquifer after a sampling event without having significantly altered the water quality. One of the primary concerns as to its applicability at SRS, and elsewhere, is whether the PWMS might resample groundwater that is returned to the aquifer during the previous sampling event. The purpose of the present investigation was to compare groundwater chemical analysis data collected at the four test wells using the PWMS vs. historical data collected using the standard monitoring program methodology to determine if the PWMS provides representative monitoring samples.The analysis of the groundwater chemical concentrations indicates that the PWMS sampling methodology acquired representative groundwater samples at monitoring wells ABP-1A, ABP-4, ARP-3 and BGO-33C. Representative groundwater samples are achieved if the PWMS does not resample groundwater that has been purged and returned during a previous sampling event. Initial screening calculations, conducted prior to the selection of these four wells, indicated that groundwater velocities were high enough under the ambient hydraulic gradients to preclude resampling from occurring at the time intervals that were used at each well. Corroborating evidence included a tracer test that was conducted at BGO-33C, the high degree of similarity between analyte concentrations derived from the PWMS samples and those obtained from historical protocol sampling, as well as the fact that PWMS data extend all previously existing concentration

  9. GROUND WATER MONITORING AND SAMPLING: MULTI-LEVEL VERSUS TRADITIONAL METHODS WHATS WHAT?

    EPA Science Inventory

    After years of research and many publications, the question still remains: What is the best method to collect representative ground water samples from monitoring wells? Numerous systems and devices are currently available for obtaining both multi-level samples as well as traditi...

  10. HYDROLYSIS OF MTBE IN GROUND WATER SAMPLES PRESERVED WITIH HYDROCHLORIC ACID

    EPA Science Inventory

    Conventional sampling and analytical protocols have poor sensitivity for fuel oxygenates that are alcohols, such as TBA. Because alcohols tend to stay with the water samples, they are not efficiently transferred to the gas chromatograph for separation and analysis. A common tec...

  11. Qualilty, isotopes, and radiochemistry of water sampled from the Upper Moenkopi Village water-supply wells, Coconino County, Arizona

    USGS Publications Warehouse

    Carruth, Rob; Beisner, Kimberly; Smith, Greg

    2013-01-01

    The Hopi Tribe Water Resources Program has granted contracts for studies to evaluate water supply conditions for the Moenkopi villages in Coconino County, Arizona. The Moenkopi villages include Upper Moenkopi Village and the village of Lower Moencopi, both on the Hopi Indian Reservation south of the Navajo community of Tuba City. These investigations have determined that water supplies are limited and vulnerable to several potential sources of contamination, including the Tuba City Landfill and a former uranium processing facility known as the Rare Metals Mill. Studies are ongoing to determine if uranium and other metals in groundwater beneath the landfill are greater than regional groundwater concentrations. The source of water supply for the Upper Moenkopi Village is three public-supply wells. The wells are referred to as MSW-1, MSW-2, and MSW-3 and all three wells obtain water from the regionally extensive N aquifer. The N aquifer is the principal aquifer in this region of northern Arizona and consists of thick beds of sandstone between less permeable layers of siltstone and mudstone. The relatively fine-grained character of the N aquifer inhibits rapid movement of water and large yields to wells. In recent years, water levels have declined in the three public-supply wells, causing concern that the current water supply will not be able to accommodate peak demand and allow for residential and economic growth. Analyses of major ions, nutrients, selected trace metals, stable and radioactive isotopes, and radiochemistry were performed on the groundwater samples from the three public-supply wells to describe general water-quality conditions and groundwater ages in and immediately surrounding the Upper Moenkopi Village area. None of the water samples collected from the public-supply wells exceeded the U.S. Environmental Protection Agency primary drinking water standards. The ratios of the major dissolved ions from the samples collected from MSW-1 and MSW-2 indicate

  12. May 2011 Groundwater and Surface Water Sampling at the Rio Blanco, Colorado, Site (Data Validation Package)

    SciTech Connect

    2011-12-01

    Annual sampling was conducted at the Rio Blanco, Colorado, site for the Long-Term Hydrologic Monitoring Program May 16-17, 2011, to monitor groundwater and surface water for potential radionuclide contamination. Sampling and analyses were conducted as specified in Sampling and Analysis Plan for the U.S. Department of Energy Office of Legacy Management Sites (LMS/PRO/S04351, continually updated). A duplicate sample was collected from location Johnson Artesian WL. Samples were analyzed by the U.S. Environmental Protection Agency (EPA) Radiation&Indoor Environments National Laboratory in Las Vegas, Nevada. Samples were analyzed for gamma-emitting radionuclides by high-resolution gamma spectrometry, and for tritium using the conventional method. Tritium was not measured using the enrichment method because the EPA laboratory no longer offers that service. Results of this monitoring at the Rio Blanco site demonstrate that groundwater and surface water outside the boundaries have not been affected by project-related contaminants.

  13. Identification of Phyllosilicates in Mudstone Samples Using Water Releases Detected by the Sample Analysis at Mars (SAM) Instrument in Gale Crater, Mars

    NASA Technical Reports Server (NTRS)

    Hogancamp, J. V. (Clark); Ming, D. W.; McAdam, A. C.; Archer, P. D.; Morris, R. V.; Bristow, T. F.; Rampe, E. B.; Mahaffy, P. R.; Gellert, R.

    2017-01-01

    The Sample Analysis at Mars (SAM) instrument on board the Curiosity Rover has detected high temperature water releases from mud-stones in the areas of Yellowknife Bay, Pahrump Hills, Naukluft Plateau, and Murray Buttes in Gale crater. Dehydroxylation of phyllosilicates may have caused the high temperature water releases observed in these samples. Because each type of phyllosilicate undergoes dehydroxylation at distinct temperatures, these water releases can be used to help constrain the type of phyllosilicate present in each sample.

  14. Litter Decomposition in a Semiarid Dune Grassland: Neutral Effect of Water Supply and Inhibitory Effect of Nitrogen Addition

    PubMed Central

    Li, Yulin; Ning, Zhiying; Cui, Duo; Mao, Wei; Bi, Jingdong; Zhao, Xueyong

    2016-01-01

    Background The decomposition of plant material in arid ecosystems is considered to be substantially controlled by water and N availability. The responses of litter decomposition to external N and water, however, remain controversial, and the interactive effects of supplementary N and water also have been largely unexamined. Methodology/Principal Findings A 3.5-year field experiment with supplementary nitrogen and water was conducted to assess the effects of N and water addition on mass loss and nitrogen release in leaves and fine roots of three dominant plant species (i.e., Artemisia halondendron, Setaria viridis, and Phragmites australis) with contrasting substrate chemistry (e.g. N concentration, lignin content in this study) in a desertified dune grassland of Inner Mongolia, China. The treatments included N addition, water addition, combination of N and water, and an untreated control. The decomposition rate in both leaves and roots was related to the initial litter N and lignin concentrations of the three species. However, litter quality did not explain the slower mass loss in roots than in leaves in the present study, and thus warrant further research. Nitrogen addition, either alone or in combination with water, significantly inhibited dry mass loss and N release in the leaves and roots of the three species, whereas water input had little effect on the decomposition of leaf litter and fine roots, suggesting that there was no interactive effect of supplementary N and water on litter decomposition in this system. Furthermore, our results clearly indicate that the inhibitory effects of external N on dry mass loss and nitrogen release are relatively strong in high-lignin litter compared with low-lignin litter. Conclusion/Significance These findings suggest that increasing precipitation hardly facilitates ecosystem carbon turnover but atmospheric N deposition can enhance carbon sequestration and nitrogen retention in desertified dune grasslands of northern China

  15. May 2013 Groundwater and Surface Water Sampling at the Rio Blanco, Colorado, Site (Data Validation Package)

    SciTech Connect

    2013-10-01

    Annual sampling was conducted at the Rio Blanco, Colorado, site for the Long-Term Hydrologic Monitoring Program May 14-16, 2013, to monitor groundwater and surface water for potential radionuclide contamination. Sampling and analyses were conducted as specified in Sampling and Analysis Plan for the U.S. Department of Energy Office of Legacy Management Sites (LMS/PRO/S04351, continually updated). A duplicate sample was collected from location CER #1 Black Sulphur. Samples were analyzed for gamma-emitting radionuclides by high-resolution gamma spectrometry and for tritium using the conventional and enrichment methods.

  16. Proton transfer pathways in an aspartate-water cluster sampled by a network of discrete states

    NASA Astrophysics Data System (ADS)

    Reidelbach, Marco; Betz, Fridtjof; Mäusle, Raquel Maya; Imhof, Petra

    2016-08-01

    Proton transfer reactions are complex transitions due to the size and flexibility of the hydrogen-bonded networks along which the protons may ;hop;. The combination of molecular dynamics based sampling of water positions and orientations with direct sampling of proton positions is an efficient way to capture the interplay of these degrees of freedom in a transition network. The energetically most favourable pathway in the proton transfer network computed for an aspartate-water cluster shows the pre-orientation of water molecules and aspartate side chains to be a pre-requisite for the subsequent concerted proton transfer to the product state.

  17. Salinity of ground water at sampling wells located in southeastern Nassau County, Long Island, New York

    USGS Publications Warehouse

    Lusczynski, Norbert J.

    1950-01-01

    In 1939, a special program for the systematic collection of chloride data in southeastern Nassau County was inaugurated in which three agencies participated. The Nassau County Department of Public Works constructed the sampling wells, the Ground Water Branch of the U.S. Geological Survey began to collect at period intervals water samples which were analysed at the Mount Prospect Laboratory of the New York Department of Water Supply, Gas and Electricity, The Nassau County Department of Public Works and the U.S. Geological Survey have continued financial cooperation for the maintenance of this program up to the present time.

  18. Comparison of sampling strategies for monitoring water quality in mesoscale Canadian Prairie watersheds.

    PubMed

    Ross, Cody; Petzold, Halya; Penner, Amber; Ali, Genevieve

    2015-07-01

    The Canadian Prairies are subject to cold winter dynamics, spring snowmelt runoff, and summer storms; a process variability that makes it difficult to identify an adequate sampling strategy for capturing representative water quality data. Hence, our research objective was to compare multiple water quality sampling strategies for Prairie watersheds and rank them based on operational and statistical criteria. The focus was on the Catfish Creek Watershed (Manitoba, Canada), which drains into the hypereutrophic Lake Winnipeg. Water samples were collected every 7 h during the 2013 open-water season and notably analyzed for nitrate and orthophosphate. The original high-frequency dataset (7 h) was then deconstructed into lower-frequency datasets to mimic strategies involving sample collection on a daily, weekly, bi-weekly, monthly, and seasonal basis. A comparison and decision matrix was also built to assess the ability of the lower-frequency datasets to retain the statistical properties of the original (7 h) dataset. Results indicate that nutrient concentrations vary significantly over short timescales and are affected by both sampling time (day versus night) and water level fluctuations. The decision matrix revealed that seasonal sampling is sufficient when the goal is only to capture mean water quality conditions; however, sub-daily to daily sampling is required for accurate process signal representation. While we acknowledge that sampling programs designed by researchers and public agencies are often driven by different goals, we found daily sampling to be the most parsimonious strategy for the study watershed and suggest that it would help to better quantify nutrient loads to Lake Winnipeg.

  19. Concentration of ions in selected bottled water samples sold in Malaysia

    NASA Astrophysics Data System (ADS)

    Aris, Ahmad Zaharin; Kam, Ryan Chuan Yang; Lim, Ai Phing; Praveena, Sarva Mangala

    2013-03-01

    Many consumers around the world, including Malaysians, have turned to bottled water as their main source of drinking water. The aim of this study is to determine the physical and chemical properties of bottled water samples sold in Selangor, Malaysia. A total of 20 bottled water brands consisting of `natural mineral (NM)' and `packaged drinking (PD)' types were randomly collected and analyzed for their physical-chemical characteristics: hydrogen ion concentration (pH), electrical conductivity (EC) and total dissolved solids (TDS), selected major ions: calcium (Ca), potassium (K), magnesium (Mg) and sodium (Na), and minor trace constituents: copper (Cu) and zinc (Zn) to ascertain their suitability for human consumption. The results obtained were compared with guideline values recommended by World Health Organization (WHO) and Malaysian Ministry of Health (MMOH), respectively. It was found that all bottled water samples were in accordance with the guidelines set by WHO and MMOH except for one sample (D3) which was below the pH limit of 6.5. Both NM and PD bottled water were dominated by Na + K > Ca > Mg. Low values for EC and TDS in the bottled water samples showed that water was deficient in essential elements, likely an indication that these were removed by water treatment. Minerals like major ions were present in very low concentrations which could pose a risk to individuals who consume this water on a regular basis. Generally, the overall quality of the supplied bottled water was in accordance to standards and guidelines set by WHO and MMOH and safe for consumption.

  20. Ground-water quality in east-central New Jersey, and a plan for sampling networks

    USGS Publications Warehouse

    Harriman, D.A.; Sargent, B.P.

    1985-01-01

    Groundwater quality was evaluated in seven confined aquifers and the water table aquifer in east-central New Jersey based on 237 analyses of samples collected in 1981-82, and 225 older analyses. Investigation of the effect of land use on water quality and several sampling network proposals for the region are reported. Generally, water in the confined aquifers is of satisfactory quality for human consumption and most other uses. Iron (Fe) and manganese (Mn) concentrations exceed U.S. EPA drinking water standards in some wells screened in the Potomac-Raritan-Magothy aquifer system. Sodium (Na) concentrations in samples from three wells more than 800 ft deep in the Englishtown aquifer exceed the standard. Iron and Mn concentrations in this aquifer may also exceed the standards. Iron concentrations in the Wenonah-Mount Laurel aquifer exceed the standard. Based on 15 analyses of water from the Vincetown aquifer, Mn is the only constituent that exceeds the drinking water standard. In the Manasquan aquifer, 4 of the 16 Na determinations exceed the standard, and 8 of 16 Fe determinations exceed the standard. Water quality in the Atlantic City 800-ft sand is generally satisfactory. However, 12 Fe and 1 of 12 Mn determinations exceed the standards. For the Rio Grande water-bearing zone, 1 of 3 Fe determinations exceed the standard. The Kirkwood-Cohansey aquifer system (the water table aquifer) was the most thoroughly sampled (249 chemical analyses from 209 wells). Dissolved solids, chloride, Fe, nitrate, and Mn concentrations exceed drinking water standards in some areas. The results of chi-square tests of constituent distributions based on analyses from 158 wells in the water table aquifer indicate that calcium is higher in industrial and commercial areas; and Mg, chloride, and nitrate-plus-nitrite is higher in residential areas. (Author 's abstract)

  1. Analysis of core soil and water samples from the Cactus Crater Disposal Site at Enewetak atoll

    SciTech Connect

    Robison, W.L.; Noshkin, V.E.

    1981-02-18

    Core soil samples and water samples were collected from the Cactus Crater Disposal Site at Enewetak for analysis of /sup 137/Cs, /sup 90/Sr, /sup 239 +240/Pu and /sup 241/Am by both gamma spectroscopy and, through a contractor laboratory, by wet chemistry procedures. The samples processing methods, the analytical methods and the analytical quality control are all procedures developed for the continuing Marshall Island radioecology and dose assessment work.

  2. White HDPE bottles as source of serious contamination of water samples with Ba and Zn.

    PubMed

    Reimann, Clemens; Grimstvedt, Andreas; Frengstad, Bjørn; Finne, Tor Erik

    2007-03-15

    During a recent study of surface water quality factory new white high-density polyethylene (HDPE) bottles were used for collecting the water samples. According to the established field protocol of the Geological Survey of Norway the bottles were twice carefully rinsed with water in the field prior to sampling. Several blank samples using milli-Q (ELGA) water (>18.2 MOmega) were also prepared. On checking the analytical results the blanks returned values of Ag, Ba, Sr, V, Zn and Zr. For Ba and Zn the values (c. 300 microg/l and 95 microg/l) were about 10 times above the concentrations that can be expected in natural waters. A laboratory test of the bottles demonstrated that the bottles contaminate the samples with significant amounts of Ba and Zn and some Sr. Simple acid washing of the bottles prior to use did not solve the contamination problem for Ba and Zn. The results suggest that there may exist "clean" and "dirty" HDPE bottles depending on manufacturer/production process. When collecting water samples it is mandatory to check bottles regularly as a possible source of contamination.

  3. THE CARCINOGENIC RESPONSE TO A MIXTURE OF DRINKING WATER DISINFECTION BY-PRODUCTS (DBP) WAS LESS THAN ADDITIVE

    EPA Science Inventory

    THE CARCINOGENIC RESPONSE TO A MIXTURE OF DRINKING WATER DISINFECTION BY -PRODUCTS (DBP) W AS LESS THAN ADDITIVE.

    Current default risk assessments for chemical mixtures assume additivity of carcinogenic effects but this may under or over represent the actual biological res...

  4. Expanding the scope of Lewis acid catalysis in water: remarkable ligand acceleration of aqueous ytterbium triflate catalyzed Michael addition reactions.

    PubMed

    Ding, Rui; Katebzadeh, Kambiz; Roman, Lisa; Bergquist, Karl-Erik; Lindström, Ulf M

    2006-01-06

    [reaction: see text] Significant rate acceleration of metal-catalyzed Michael addition reactions in water was observed upon addition of small, dibasic ligands. Ytterbium triflate and TMEDA was the most effective combination leading to a nearly 20-fold faster reaction than in the absence of ligand.

  5. Backflushing Filters for Field Processing of Water Samples Prior to Trace-Element Analyses

    USGS Publications Warehouse

    Kennedy, V.C.; Jenne, E.A.; Burchard, J.M.

    1976-01-01

    A portable unit is described for filtering water samples at field sites in such a manner that the filtrate is suitable for analysis not only of major constituents but also of trace elments at the mocrogram-per-liter level. A battery-operated peristaltic pump forces the water sample through medical-grade silicone tubing into and through an all-plastic in-line filter which can be backflushed when sediment clogs the filter membrane. Initial filtration rate exceeds 500 milliliter/minute and, because of the backflushing feature, a total time for filtering high-sediment-bearing waster samples is greatly reduced. (Woodard-USGS)

  6. Regression modeling of particle size distributions in urban storm water: advancements through improved sample collection methods

    USGS Publications Warehouse

    Fienen, Michael N.; Selbig, William R.

    2012-01-01

    A new sample collection system was developed to improve the representation of sediment entrained in urban storm water by integrating water quality samples from the entire water column. The depth-integrated sampler arm (DISA) was able to mitigate sediment stratification bias in storm water, thereby improving the characterization of suspended-sediment concentration and particle size distribution at three independent study locations. Use of the DISA decreased variability, which improved statistical regression to predict particle size distribution using surrogate environmental parameters, such as precipitation depth and intensity. The performance of this statistical modeling technique was compared to results using traditional fixed-point sampling methods and was found to perform better. When environmental parameters can be used to predict particle size distributions, environmental managers have more options when characterizing concentrations, loads, and particle size distributions in urban runoff.

  7. Analysis of bromate in drinking water using liquid chromatography-tandem mass spectrometry without sample pretreatment.

    PubMed

    Kosaka, Koji; Asami, Mari; Takei, Kanako; Akiba, Michihiro

    2011-01-01

    An analytical method for determining bromate in drinking water was developed using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The (18)O-enriched bromate was used as an internal standard. The limit of quantification (LOQ) of bromate was 0.2 µg/L. The peak of bromate was separated from those of coexisting ions (i.e., chloride, nitrate and sulfate). The relative and absolute recoveries of bromate in two drinking water samples and in a synthesized ion solution (100 mg/L chloride, 10 mg N/L nitrate, and 100 mg/L sulfate) were 99-105 and 94-105%, respectively. Bromate concentrations in 11 drinking water samples determined by LC-MS/MS were <0.2-2.3 µg/L. The results of the present study indicated that the proposed method was suitable for determining bromate concentrations in drinking water without sample pretreatment.

  8. Set up of an automatic water quality sampling system in irrigation agriculture.

    PubMed

    Heinz, Emanuel; Kraft, Philipp; Buchen, Caroline; Frede, Hans-Georg; Aquino, Eugenio; Breuer, Lutz

    2013-12-23

    We have developed a high-resolution automatic sampling system for continuous in situ measurements of stable water isotopic composition and nitrogen solutes along with hydrological information. The system facilitates concurrent monitoring of a large number of water and nutrient fluxes (ground, surface, irrigation and rain water) in irrigated agriculture. For this purpose we couple an automatic sampling system with a Wavelength-Scanned Cavity Ring Down Spectrometry System (WS-CRDS) for stable water isotope analysis (δ2H and δ18O), a reagentless hyperspectral UV photometer (ProPS) for monitoring nitrate content and various water level sensors for hydrometric information. The automatic sampling system consists of different sampling stations equipped with pumps, a switch cabinet for valve and pump control and a computer operating the system. The complete system is operated via internet-based control software, allowing supervision from nearly anywhere. The system is currently set up at the International Rice Research Institute (Los Baños, The Philippines) in a diversified rice growing system to continuously monitor water and nutrient fluxes. Here we present the system's technical set-up and provide initial proof-of-concept with results for the isotopic composition of different water sources and nitrate values from the 2012 dry season.

  9. Determination of UV filters and antimicrobial agents in environmental water samples.

    PubMed

    Cuderman, Petra; Heath, Ester

    2007-02-01

    Although there is increasing concern about residues from personal care products entering the aquatic environment and their potential to accumulate to levels that pose a health threat to humans and wildlife, we still know little about the extent and magnitude of their presence in the aquatic environment. In this study we describe a procedure for isolation, and subsequent determination, of compounds commonly added to personal care products. The compounds of interest include UV filters with the commercial name Eusolex (homosalate, 4-methylbenzylidenecamphor, benzophenone-3, octocrylene, butylmethoxydibenzoylmethane, ethylhexyl methoxycinnamate) and two common anti-microbial agents, clorophene and triclosan. Water samples were filtered, acidified, and extracted by use of solid-phase extraction. Extracted compounds were then derivatised before analysis by gas chromatography-mass spectroscopy. By use of our method we obtained limits of detection of 13-266 ng L(-1) for UV filters, and 10-186 ng L(-1) for triclosan and clorophene. Recoveries were 82-98% for deionised water and 50-98% for natural water (seawater, pool water, lake water, and river water). Samples collected in Slovenia included seventeen recreational waters (seawater, pool water, lake water, and river water; August 2004) and four wastewaters (January 2005). The most abundant UV filter was benzophenone-3 (11-400 ng L(-1)). Of the two anti-microbial agents studied, trace amounts, only, of triclosan were present in the river Kolpa (68 ng L(-1)) and in an hospital effluent (122 ng L(-1)).

  10. Helicobacter sp. recovered from drinking water biofilm sampled from a water distribution system.

    PubMed

    Park, S R; Mackay, W G; Reid, D C

    2001-04-01

    Workers examining the transmission route(s) and reservoir(s) of infection for Helicobacter pylori have postulated several environmental reservoirs for the organism, including water. Such work has, to date, concentrated on the bulk liquid in drinking water systems rather than on biofilms. Previous investigations by the authors have suggested biofilms in water distribution systems are a possible reservoir of infection. This current study comprised of an analysis of a section of cast iron mains distribution pipe removed from an urban environment in the north-east of Scotland during routine maintenance work. Immediately upon removal of the pipe section, the interior lumen was swabbed to remove the biofilm layer. Subsequent analysis for the presence of Helicobacter DNA using a nested PCR approach produced a positive result. This data provides the first evidence for the existence of Helicobacter in biofilms found in water distribution systems anywhere in the world.

  11. Organic Substances Interfere with Reverse Transcription-Quantitative PCR-Based Virus Detection in Water Samples

    PubMed Central

    Katayama, Hiroyuki; Furumai, Hiroaki

    2014-01-01

    Reverse transcription (RT)-PCR-based virus detection from water samples is occasionally hampered by organic substances that are coconcentrated during virus concentration procedures. To characterize these organic substances, samples containing commercially available humic acid, which is known to inhibit RT-PCR, and river water samples were subjected to adsorption-elution-based virus concentration using an electronegative membrane. In this study, the samples before, during, and after the concentration were analyzed in terms of organic properties and virus detection efficiencies. Two out of the three humic acid solutions resulted in RT-quantitative PCR (qPCR) inhibition that caused >3-log10-unit underestimation of spiked poliovirus. Over 60% of the organics contained in the two solutions were recovered in the concentrate, while over 60% of the organics in the uninhibited solution were lost during the concentration process. River water concentrates also caused inhibition of RT-qPCR. Organic concentrations in the river water samples increased by 2.3 to 3.9 times after the virus concentration procedure. The inhibitory samples contained organic fractions in the 10- to 100-kDa size range, which are suspected to be RT-PCR inhibitors. According to excitation-emission matrices, humic acid-like and protein-like fractions were also recovered from river water concentrates, but these fractions did not seem to affect virus detection. Our findings reveal that detailed organic analyses are effective in characterizing inhibitory substances. PMID:25527552

  12. Aqueous Processing of Atmospheric Organic Particles in Cloud Water Collected via Aircraft Sampling

    SciTech Connect

    Boone, Eric J.; Laskin, Alexander; Laskin, Julia; Wirth, Christopher; Shepson, Paul B.; Stirm, Brian H.; Pratt, Kerri A.

    2015-07-21

    Cloud water and below-cloud atmospheric particle samples were collected onboard a research aircraft during the Southern Oxidant and Aerosol Study (SOAS) over a forested region of Alabama in June 2013. The organic molecular composition of the samples was studied to gain insights into the aqueous-phase processing of organic compounds within cloud droplets. High resolution mass spectrometry with nanospray desorption electrospray ionization and direct infusion electrospray ionization were utilized to compare the organic composition of the particle and cloud water samples, respectively. Isoprene and monoterpene-derived organosulfates and oligomers were identified in both the particles and cloud water, showing the significant influence of biogenic volatile organic compound oxidation above the forested region. While the average O:C ratios of the organic compounds were similar between the atmospheric particle and cloud water samples, the chemical composition of these samples was quite different. Specifically, hydrolysis of organosulfates and formation of nitrogen-containing compounds were observed for the cloud water when compared to the atmospheric particle samples, demonstrating that cloud processing changes the composition of organic aerosol.

  13. Water soluble graphene as electrolyte additive in magnesium-air battery system

    NASA Astrophysics Data System (ADS)

    Saminathan, K.; Mayilvel Dinesh, M.; Selvam, M.; Srither, S. R.; Rajendran, V.; Kaler, Karan V. I. S.

    2015-02-01

    Magnesium-air (Mg-air) batteries are an important energy source used to power electronic equipment and automobiles. Metal-air batteries give more energy density due to surplus air involved in reduction reaction at air cathode. In this study, the scope of improvements in the efficiency of Metal-air batteries is investigated through addition of water soluble graphene (WSG) as inhibitor in NaCl electrolyte. The discharge performance, corrosion behaviour and electrochemical impedance are studied for (i) the conventional Mg-air battery using 3.5% NaCl and (ii) Mg-air battery with WSG-based 3.5% NaCl electrolyte. X-ray diffraction analysis for WSG is carried out and it shows the crystalline nature of WSG by an intense sharp peak at 26.3°. Scanning electron microscope study is also performed and shows the flake-like structure of WSG denoted by thin layers of carbon. The immersion of WSG in 3.5% NaCl electrolyte increased the current density from 13.24 to 19.33 mA cm-2. Meanwhile, the WSG-based Mg-air battery was found to hold specific discharge capacity of 1030.71 mAh g-1, which was higher than that obtained in 3.5% NaCl electrolyte (i.e., 822.85 mAh g-1). The WSG-based Mg-air battery shows good self-discharge capacity and higher electrochemical activity during discharge.

  14. Magnetic nanoparticles with hydrophobicity and hydrophilicity for solid-phase extraction of polycyclic aromatic hydrocarbons from environmental water samples.

    PubMed

    Xue, Shu-Wen; Tang, Min-Qiong; Xu, Li; Shi, Zhi-guo

    2015-09-11

    Magnetic nanoparticles (MNPs) featured with divinylbenzene (DVB) and sulfonate functionalities (Fe3O4-DVB-SO3(-)) were prepared via "thiol-ene" click chemistry. The hydrophobic DVB moieties were dedicated for extraction while the hydrophilic sulfonate groups were designed for dispersing the MNPs in aqueous sample solution. Thus, the specially designed material could ensure operational convenience and improve reproducibility during extraction. The application of the material was demonstrated by the extraction of polycyclic aromatic hydrocarbons (PAHs) from environmental water samples followed by gas chromatography-mass spectrometric analysis. The main factors influencing the extraction, including the type of the desorption solvent, the agitation mode, the amount of MNPs, extraction and desorption time and salt addition in sample solution, were investigated in detail. Under the optimized conditions, the proposed method showed satisfactory reproducibility with intra-day and inter-day relative standard deviations less than 16.5% and 21.2%, and low limits of detection of 1.1pgmL(-1), 0.8pgmL(-1), 1.1pgmL(-1), 1.4pgmL(-1), 0.6pgmL(-1), 2.1pgmL(-1) and 0.7pgmL(-1) for naphthalene, acenaphthene, fluorine, phenanthrene, anthracene, fluoranthene and pyrene, respectively. The developed method was also successfully used for determination of the PAHs in genuine lake and river environmental water samples by standard addition method. All the studied PAHs were detected in these waters with comparable results by the standard liquid-liquid extraction method. The developed MNPs with dual property of hydrophobicity and hydrophilicity were suitable for the treatment of water samples. The magnetic solid phase extraction based on this material was reliable and convenient. It has great potential in the preconcentration of trace analytes in complex matrix.

  15. Nutrient and water addition effects on day- and night-time conductance and transpiration in a C3 desert annual.

    PubMed

    Ludwig, Fulco; Jewitt, Rebecca A; Donovan, Lisa A

    2006-06-01

    Recent research has shown that many C3 plant species have significant stomatal opening and transpire water at night even in desert habitats. Day-time stomatal regulation is expected to maximize carbon gain and prevent runaway cavitation, but little is known about the effect of soil resource availability on night-time stomatal conductance (g) and transpiration (E). Water (low and high) and nutrients (low and high) were applied factorially during the growing season to naturally occurring seedlings of the annual Helianthus anomalus. Plant height and biomass were greatest in the treatment where both water and nutrients were added, confirming resource limitations in this habitat. Plants from all treatments showed significant night-time g (approximately 0.07 mol m(-2) s(-1)) and E (approximately 1.5 mol m(-2) s(-1)). In July, water and nutrient additions had few effects on day- or night-time gas exchange. In August, however, plants in the nutrient addition treatments had lower day-time photosynthesis, g and E, paralleled by lower night-time g and E. Lower predawn water potentials and higher integrated photosynthetic water-use efficiency suggests that the nutrient addition indirectly induced a mild water stress. Thus, soil resources can affect night-time g and E in a manner parallel to day-time, although additional factors may also be involved.

  16. Spatio-temporal representativeness of euphotic depth in situ sampling in transitional coastal waters

    NASA Astrophysics Data System (ADS)

    Luhtala, Hanna; Tolvanen, Harri

    2016-06-01

    In dynamic coastal waters, the representativeness of spot sampling is limited to the measurement time and place due to local heterogeneity and irregular water property fluctuations. We assessed the representativeness of in situ sampling by analysing spot-sampled depth profiles of photosynthetically active radiation (PAR) in dynamic coastal archipelago waters in the south-western Finnish coast of the Baltic Sea. First, we assessed the role of spatio-temporality within the underwater light dynamics. As a part of this approach, an anomaly detection procedure was tested on a dataset including a large archipelago area and extensive temporal coverage throughout the ice-free season. The results suggest that euphotic depth variability should be treated as a spatio-temporal process rather than considering spatial and temporal dimensions separately. Second, we assessed the representativeness of spot sampling through statistical analysis of comparative data from spatially denser sampling on three test sites on two optically different occasions. The datasets revealed variability in different dimensions and scales. The suitability of a dataset to reveal wanted phenomena can usually be improved by careful planning and by clearly defining the data sampling objectives beforehand. Nonetheless, conducting a sufficient in situ sampling in dynamic coastal area is still challenging: detecting the general patterns at all the relevant dimensions is complicated by the randomness effect, which reduces the reliability of spot samples on a more detailed scale. Our results indicate that good representativeness of a euphotic depth sampling location is not a stable feature in a highly dynamic environment.

  17. Iodine speciation in coastal and inland bathing waters and seaweeds extracts using a sequential injection standard addition flow-batch method.

    PubMed

    Santos, Inês C; Mesquita, Raquel B R; Bordalo, Adriano A; Rangel, António O S S

    2015-02-01

    The present work describes the development of a sequential injection standard addition method for iodine speciation in bathing waters and seaweeds extracts without prior sample treatment. Iodine speciation was obtained by assessing the iodide and iodate content, the two inorganic forms of iodine in waters. For the determination of iodide, an iodide ion selective electrode (ISE) was used. The indirect determination of iodate was based on the spectrophotometric determination of nitrite (Griess reaction). For the iodate measurement, a mixing chamber was employed (flow batch approach) to explore the inherent efficient mixing, essential for the indirect determination of iodate. The application of the standard addition method enabled detection limits of 0.14 µM for iodide and 0.02 µM for iodate, together with the direct introduction of the target water samples, coastal and inland bathing waters. The results obtained were in agreement with those obtained by ICP-MS and a colorimetric reference procedure. Recovery tests also confirmed the accuracy of the developed method which was effectively applied to bathing waters and seaweed extracts.

  18. Detection of Legionella pneumophila in environmental water samples using a fluorescein conjugated monoclonal antibody.

    PubMed Central

    Makin, T.; Hart, C. A.

    1989-01-01

    Sixty-three environmental water samples from various sources were examined for the presence of Legionella pneumophila with a commercially available direct fluorescent monoclonal antibody (GS), an indirect fluorescent antibody test (IFAT) and culture. GS detected L. pneumophila in 94% and 100% of environmental water samples which were culture and IFAT positive for L. pneumophila, respectively. IFAT detected 69% of L. pneumophila culture positive samples. Cultures of L. pneumophila serogroups 1 to 12, 14 and non-L. pneumophila bacteria which may be found in water, and bacteria containing non-specific binding proteins, were stained by GS and IFAT. GS identified all serogroups of L. pneumophila and did not cross react with any non-L. pneumophila bacteria. L. pneumophila in environmental samples was easy to detect against a clear dark background when stained with GS. Images Fig. 1 PMID:2673821

  19. Water-quality assessment of south-central Texas : comparison of water quality in surface-water samples collected manually and by automated samplers

    USGS Publications Warehouse

    Ging, Patricia B.

    1999-01-01

    Surface-water sampling protocols of the U.S. Geological Survey National Water-Quality Assessment (NAWQA) Program specify samples for most properties and constituents to be collected manually in equal-width increments across a stream channel and composited for analysis. Single-point sampling with an automated sampler (autosampler) during storms was proposed in the upper part of the South-Central Texas NAWQA study unit, raising the question of whether property and constituent concentrations from automatically collected samples differ significantly from those in samples collected manually. Statistical (Wilcoxon signed-rank test) analyses of 3 to 16 paired concentrations for each of 26 properties and constituents from water samples collected using both methods at eight sites in the upper part of the study unit indicated that there were no significant differences in concentrations for dissolved constituents, other than calcium and organic carbon.

  20. Detection of protozoa in water samples by formalin/ether concentration method.

    PubMed

    Lora-Suarez, Fabiana; Rivera, Raul; Triviño-Valencia, Jessica; Gomez-Marin, Jorge E

    2016-09-01

    Methods to detect protozoa in water samples are expensive and laborious. We evaluated the formalin/ether concentration method to detect Giardia sp., Cryptosporidium sp. and Toxoplasma in water. In order to test the properties of the method, we spiked water samples with different amounts of each protozoa (0, 10 and 50 cysts or oocysts) in a volume of 10 L of water. Immunofluorescence assay was used for detection of Giardia and Cryptosporidium. Toxoplasma oocysts were identified by morphology. The mean percent of recovery in 10 repetitions of the entire method, in 10 samples spiked with ten parasites and read by three different observers, were for Cryptosporidium 71.3 ± 12, for Giardia 63 ± 10 and for Toxoplasma 91.6 ± 9 and the relative standard deviation of the method was of 17.5, 17.2 and 9.8, respectively. Intraobserver variation as measured by intraclass correlation coefficient, was fair for Toxoplasma, moderate for Cryptosporidium and almost perfect for Giardia. The method was then applied in 77 samples of raw and drinkable water in three different plant of water treatment. Cryptosporidium was found in 28 of 77 samples (36%) and Giardia in 31 of 77 samples (40%). Theses results identified significant differences in treatment process to reduce the presence of Giardia and Cryptosporidium. In conclusion, the formalin ether method to concentrate protozoa in water is a new alternative for low resources countries, where is urgently need to monitor and follow the presence of theses protozoa in drinkable water.

  1. Identification and Genotyping of Mycobacterium tuberculosis Isolated From Water and Soil Samples of a Metropolitan City

    PubMed Central

    Velayati, Ali Akbar; Farnia, Parissa; Mozafari, Mohadese; Malekshahian, Donya; Farahbod, Amir Masoud; Seif, Shima; Rahideh, Snaz

    2015-01-01

    BACKGROUND: The potential role of environmental Mycobacterium tuberculosis in the epidemiology of TB remains unknown. We investigated the transmission of M tuberculosis from humans to the environment and the possible transmission of M tuberculosis from the environment to humans. METHODS: A total of 1,500 samples were collected from three counties of the Tehran, Iran metropolitan area from February 2012 to January 2014. A total of 700 water samples (47%) and 800 soil samples (53%) were collected. Spoligotyping and the mycobacterial interspersed repetitive units-variable number of tandem repeats typing method were performed on DNA extracted from single colonies. Genotypes of M tuberculosis strains isolated from the environment were compared with the genotypes obtained from 55 patients with confirmed pulmonary TB diagnosed during the study period in the same three counties. RESULTS: M tuberculosis was isolated from 11 of 800 soil samples (1%) and 71 of 700 water samples (10%). T family (56 of 82, 68%) followed by Delhi/CAS (11 of 82, 13.4%) were the most frequent M tuberculosis superfamilies in both water and soil samples. Overall, 27.7% of isolates in clusters were related. No related typing patterns were detected between soil, water, and clinical isolates. The most frequent superfamily of M tuberculosis in clinical isolates was Delhi/CAS (142, 30.3%) followed by NEW-1 (127, 27%). The bacilli in contaminated soil (36%) and damp water (8.4%) remained reculturable in some samples up to 9 months. CONCLUSIONS: Although the dominant M tuberculosis superfamilies in soil and water did not correspond to the dominant M tuberculosis family in patients, the presence of circulating genotypes of M tuberculosis in soil and water highlight the risk of transmission. PMID:25340935

  2. The Salmonella mutagenicity of industrial, surface and ground water samples of Aligarh region of India.

    PubMed

    Siddiqui, Athar Habib; Ahmad, Masood

    2003-11-10

    The genotoxicity of three water bodies, viz. industrial waste water of Aligarh city, ground water pumped out from the industrial area of Aligarh, and river water of Yamuna, downstream of Agra, was carried out by means of Ames plate incorporation test and the Ames fluctuation test. All the test samples were significantly mutagenic in both the testing systems. The ground water and river water samples were subjected to XAD concentration prior to the mutagenicity/genotoxicity testing, while the industrial waste water was used directly. Whereas TA98, TA102 and TA104 strains have been found to be maximally sensitive in the Ames plate incorporation assay conducted for various water samples, TA98 and TA100 strains were the most responsive strains in the Ames fluctuation test. The apparent disparity in the sensitivity patterns of various Ames strains by plate incorporation and fluctuation assays could be attributed to a large extent to the different conventional ways of interpretation of the data in these systems.

  3. Influence of water content on Raman spectroscopy characterization of skin sample

    PubMed Central

    Kim, Soogeun; Byun, Kyung Min; Lee, Soo Yeol

    2017-01-01

    We report that the Raman spectrum obtained from porcine skin varies significantly with the change of skin water content. At different water contents from 40 to 55 wt.%, the Raman spectra results using confocal Raman spectroscopy show that the spectral variation of porcine skin is highly affected by skin water content. Experimental data are consistent with the Monte Carlo calculation and it is proved that the intensity of the Raman spectrum depends on the angle distribution and collection efficiency of backscattered light from the sample surface for a varied water content. It is suggested that water content for a given skin sample should be controlled carefully to minimize errors and deviations in the Raman peak analyses. PMID:28271008

  4. Influence of water content on Raman spectroscopy characterization of skin sample.

    PubMed

    Kim, Soogeun; Byun, Kyung Min; Lee, Soo Yeol

    2017-02-01

    We report that the Raman spectrum obtained from porcine skin varies significantly with the change of skin water content. At different water contents from 40 to 55 wt.%, the Raman spectra results using confocal Raman spectroscopy show that the spectral variation of porcine skin is highly affected by skin water content. Experimental data are consistent with the Monte Carlo calculation and it is proved that the intensity of the Raman spectrum depends on the angle distribution and collection efficiency of backscattered light from the sample surface for a varied water content. It is suggested that water content for a given skin sample should be controlled carefully to minimize errors and deviations in the Raman peak analyses.

  5. Effects of physical and chemical heterogeneity on water-quality samples obtained from wells

    USGS Publications Warehouse

    Reilly, Thomas E.; Gibs, Jacob

    1993-01-01

    Factors that affect the mass of chemical constituents entering a well include the distributions of flow rate and chemical concentrations along and near the screened or open section of the well. Assuming a layered porous medium (with each layer being characterized by a uniform hydraulic conductivity and chemical concentration), a knowledge of the flow from each layer along the screened zone and of the chemical concentrations in each layer enables the total mass entering the well to be determined. Analyses of hypothetical systems and a site at Galloway, NJ, provide insight into the temporal variation of water-quality data observed when withdrawing water from screened wells in heterogeneous ground-water systems.The analyses of hypothetical systems quantitatively indicate the cause-and-effect relations that cause temporal variability in water samples obtained from wells. Chemical constituents that have relatively uniform concentrations with depth may not show variations in concentrations in the water discharged from a well after the well is purged (evacuation of standing water in the well casing). However, chemical constituents that do not have uniform concentrations near the screened interval of the well may show variations in concentrations in the well discharge water after purging because of the physics of ground-water flow in the vicinity of the screen.Water-quality samples were obtained through time over a 30 minute period from a site at Galloway, NJ. The water samples were analyzed for aromatic hydrocarbons, and the data for benzene, toluene, and meta+para xylene were evaluated for temporal variations. Samples were taken from seven discrete zones, and the flow-weighted concentrations of benzene, toluene, and meta+para xylene all indicate an increase in concentration over time during pumping. These observed trends in time were reproduced numerically based on the estimated concentration distribution in the aquifer and the flow rates from each zone.The results of

  6. Preserving ground water samples with hydrochloric acid does not result in the formation of chloroform

    USGS Publications Warehouse

    Squillace, Paul J.; Pankow, James F.; Barbash, Jack E.; Price, Curtis V.; Zogorski, John S.

    1999-01-01

    Water samples collected for the determination of volatile organic compounds (VOCs) are often preserved with hydrochloric acid (HCl) to inhibit the biotransformation of the analytes of interest until the chemical analyses can he performed. However, it is theoretically possible that residual free chlorine in the HCl can react with dissolved organic carbon (DOC) to form chloroform via the haloform reaction. Analyses of 1501 ground water samples preserved with HCl from the U.S. Geological Survey's National Water-Quality Assessment Program indicate that chloroform was the most commonly detected VOC among 60 VOCs monitored. The DOC concentrations were not significantly larger in samples with detectable chloroform than in those with no delectable chloroform, nor was there any correlation between the concentrations of chloroform and DOC. Furthermore, chloroform was detected more frequently in shallow ground water in urban areas (28.5% of the wells sampled) than in agricultural areas (1.6% of the wells sampled), which indicates that its detection was more related to urban land-use activities than to sample acidification. These data provide strong evidence that acidification with HCl does not lead to the production of significant amounts of chloroform in ground water samples. To verify these results, an acidification study was designed to measure the concentrations of all trihalomethanes (THMs) that can form as a result of HCl preservation in ground water samples and to determine if ascorbic acid (C6H8O6) could inhibit this reaction if it did occur. This study showed that no THMs were formed as a result of HCl acidification, and that ascorbic acid had no discernible effect on the concentrations of THMs measured.

  7. Interim results of quality-control sampling of surface water for the Upper Colorado River National Water-Quality Assessment Study Unit, water years 1995-96

    USGS Publications Warehouse

    Spahr, N.E.; Boulger, R.W.

    1997-01-01

    Quality-control samples provide part of the information needed to estimate the bias and variability that result from sample collection, processing, and analysis. Quality-control samples of surface water collected for the Upper Colorado River National Water-Quality Assessment study unit for water years 1995?96 are presented and analyzed in this report. The types of quality-control samples collected include pre-processing split replicates, concurrent replicates, sequential replicates, post-processing split replicates, and field blanks. Analysis of the pre-processing split replicates, concurrent replicates, sequential replicates, and post-processing split replicates is based on differences between analytical results of the environmental samples and analytical results of the quality-control samples. Results of these comparisons indicate that variability introduced by sample collection, processing, and handling is low and will not affect interpretation of the environmental data. The differences for most water-quality constituents is on the order of plus or minus 1 or 2 lowest rounding units. A lowest rounding unit is equivalent to the magnitude of the least significant figure reported for analytical results. The use of lowest rounding units avoids some of the difficulty in comparing differences between pairs of samples when concentrations span orders of magnitude and provides a measure of the practical significance of the effect of variability. Analysis of field-blank quality-control samples indicates that with the exception of chloride and silica, no systematic contamination of samples is apparent. Chloride contamination probably was the result of incomplete rinsing of the dilute cleaning solution from the outlet ports of the decaport sample splitter. Silica contamination seems to have been introduced by the blank water. Sampling and processing procedures for water year 1997 have been modified as a result of these analyses.

  8. Hydrogen isotopes from source water to leaf lipid in a continental-scale sample network

    NASA Astrophysics Data System (ADS)

    Nelson, Daniel; Kahmen, Ansgar

    2015-04-01

    Sedimentary plant waxes are useful paleoclimate proxies because they are preserved in depositional settings on geologic timescales and the isotopic composition of the hydrogen in these molecules reflects that of the source water available during biosynthesis. This application is based largely on empirical calibrations that have demonstrated continental-scale correlations between source water and lipid hydrogen isotope values. However, the importance of variable net isotopic fractionation between source water and lipid for different species and environmental conditions is increasingly recognized. Isotopic enrichment of leaf water during transpiration is key among these secondary factors, and is itself sensitive to changes in hydroclimate. Leaf water enrichment also occurs prior to photosynthetic water uptake, and is therefore independent from cellular-level biomarker synthesis. Mechanistic models can predict the mean leaf water hydrogen isotope composition from readily available meteorological variables. This permits global-scale isoscape maps of leaf water isotopic composition and enrichment above source water to be generated, but these models have not been widely validated at continental spatial scales. We have established a network of twenty-one sites across Europe where we are sampling for leaf-, xylem-, and soil-water isotopes (H and O) at approximately 5-week intervals over the summer growing season. We augment the sample set with weekly to monthly precipitation samples and early- and late-season plant wax lipid samples. Collaborators at each site are conducting the sampling, and most sites are members of the FLUXNET tower network that also record high-resolution meteorological data. We present information on the implementation of the network and preliminary results from the 2014 summer season. The complete dataset will be used to track the evolution of water isotopes from source to leaf water and from leaf water to lipid hydrogen across diverse environments

  9. Analysis of pharmaceutical and other organic wastewater compounds in filtered and unfiltered water samples by gas chromatography/mass spectrometry

    USGS Publications Warehouse

    Zaugg, Steven D.; Phillips, Patrick J.; Smith, Steven G.

    2014-01-01

    Research on the effects of exposure of stream biota to complex mixtures of pharmaceuticals and other organic compounds associated with wastewater requires the development of additional analytical capabilities for these compounds in water samples. Two gas chromatography/mass spectrometry (GC/MS) analytical methods used at the U.S. Geological Survey National Water Quality Laboratory (NWQL) to analyze organic compounds associated with wastewater were adapted to include additional pharmaceutical and other organic compounds beginning in 2009. This report includes a description of method performance for 42 additional compounds for the filtered-water method (hereafter referred to as the filtered method) and 46 additional compounds for the unfiltered-water method (hereafter referred to as the unfiltered method). The method performance for the filtered method described in this report has been published for seven of these compounds; however, the addition of several other compounds to the filtered method and the addition of the compounds to the unfiltered method resulted in the need to document method performance for both of the modified methods. Most of these added compounds are pharmaceuticals or pharmaceutical degradates, although two nonpharmaceutical compounds are included in each method. The main pharmaceutical compound classes added to the two modified methods include muscle relaxants, opiates, analgesics, and sedatives. These types of compounds were added to the original filtered and unfiltered methods largely in response to the tentative identification of a wide range of pharmaceutical and other organic compounds in samples collected from wastewater-treatment plants. Filtered water samples are extracted by vacuum through disposable solid-phase cartridges that contain modified polystyrene-divinylbenzene resin. Unfiltered samples are extracted by using continuous liquid-liquid extraction with dichloromethane. The compounds of interest for filtered and unfiltered sample

  10. Hydrogeologic framework and sampling design for an assessment of agricultural pesticides in ground water in Pennsylvania

    USGS Publications Warehouse

    Lindsey, Bruce D.; Bickford, Tammy M.

    1999-01-01

    State agencies responsible for regulating pesticides are required by the U.S. Environmental Protection Agency to develop state management plans for specific pesticides. A key part of these management plans includes assessing the potential for contamination of ground water by pesticides throughout the state. As an example of how a statewide assessment could be implemented, a plan is presented for the Commonwealth of Pennsylvania to illustrate how a hydrogeologic framework can be used as a basis for sampling areas within a state with the highest likelihood of having elevated pesticide concentrations in ground water. The framework was created by subdividing the state into 20 areas on the basis of physiography and aquifer type. Each of these 20 hydrogeologic settings is relatively homogeneous with respect to aquifer susceptibility and pesticide use?factors that would be likely to affect pesticide concentrations in ground water. Existing data on atrazine occurrence in ground water was analyzed to determine (1) which areas of the state already have suffi- cient samples collected to make statistical comparisons among hydrogeologic settings, and (2) the effect of factors such as land use and aquifer characteristics on pesticide occurrence. The theoretical vulnerability and the results of the data analysis were used to rank each of the 20 hydrogeologic settings on the basis of vulnerability of ground water to contamination by pesticides. Example sampling plans are presented for nine of the hydrogeologic settings that lack sufficient data to assess vulnerability to contamination. Of the highest priority areas of the state, two out of four have been adequately sampled, one of the three areas of moderate to high priority has been adequately sampled, four of the nine areas of moderate to low priority have been adequately sampled, and none of the three low priority areas have been sampled. Sampling to date has shown that, even in the most vulnerable hydrogeologic settings

  11. Solid-phase microextraction for the analysis of short-chain chlorinated paraffins in water samples.

    PubMed

    Castells, P; Santos, F J; Galceran, M T

    2003-01-10

    A novel solid-phase microextraction (SPME) method coupled to gas chromatography with electron capture detection (GC-ECD) was developed as an alternative to liquid-liquid and solid-phase extraction for the analysis of short-chain chlorinated paraffins (SCCPs) in water samples. The extraction efficiency of five different commercially available fibres was evaluated and the 100-microm polydimethylsiloxane coating was the most suitable for the absorption of the SCCPs. Optimisation of several SPME parameters, such as extraction time and temperature, ionic strength and desorption time, was performed. Quality parameters were established using Milli-Q, tap water and river water. Linearity ranged between 0.06 and 6 microg l(-1) for spiked Milli-Q water and between 0.6 and 6 microg l(-1) for natural waters. The precision of the SPME-GC-ECD method for the three aqueous matrices was similar and gave relative standard deviations (RSD) between 12 and 14%. The limit of detection (LOD) was 0.02 microg l(-1) for Milli-Q water and 0.3 microg l(-1) for both tap water and river water. The optimised SPME-GC-ECD method was successfully applied to the determination of SCCPs in river water samples.

  12. Determination of (210)Po in drinking water and urine samples using copper sulfide microprecipitation.

    PubMed

    Guérin, Nicolas; Dai, Xiongxin

    2014-06-17

    Polonium-210 ((210)Po) can be rapidly determined in drinking water and urine samples by alpha spectrometry using copper sulfide (CuS) microprecipitation. For drinking water, Po in 10 mL samples was directly coprecipitated onto the filter for alpha counting without any purification. For urine, 10 mL of sample was heated, oxidized with KBrO3 for a short time (∼5 min), and subsequently centrifuged to remove the suspended organic matter. The CuS microprecipitation was then applied to the supernatant. Large batches of samples can be prepared using this technique with high recoveries (∼85%). The figures of merit of the methods were determined, and the developed methods fulfill the requirements for emergency and routine radioassays. The efficiency and reliability of the procedures were confirmed using spiked samples.

  13. Formation of an artifact of diclofenac during acidic extraction of environmental water samples.

    PubMed

    Reddersen, K; Heberer, Th

    2003-09-05

    Solid-phase extraction at an acidic pH is used as a common sample preparation method for analyzing residues of the analgesic drug diclofenac (2-[(2,6-dichlorophenyl)amino] benzeneacetic acid) in environmental water samples. This paper describes the matrix-dependent formation of an artifact of diclofenac during sample preparation resulting in an up to 40% underestimation of diclofenac concentrations especially in matrix-prone samples such as sewage effluents or surface water. The artifact most likely being formed during acidification of the sample was unequivocally identified as 1-(2,6-dichlorophenyl)indolin-2-one by capillary gas chromatography-mass spectrometry. To avoid an underestimation of the analytical results quantification of both diclofenac and its artifact is recommended.

  14. May 2012 Groundwater and Surface Water Sampling at the Rio Blanco, Colorado, Site (Data Validation Package)

    SciTech Connect

    2012-12-01

    Annual sampling was conducted at the Rio Blanco, Colorado, site for the Long-Term Hydrologic Monitoring Program May 9-10, 2012, to monitor groundwater and surface water for potential radionuclide contamination. Sampling and analyses were conducted as specified in Sampling and Analysis Plan for the U.S. Department of Energy Office of Legacy Management Sites (LMS/PRO/S04351, continually updated). A duplicate sample was collected from location Johnson Artesian WL. Samples were analyzed for gamma-emitting radionuclides by high-resolution gamma spectrometry and for tritium using the conventional and enrichment methods. Results of this monitoring at the Rio Blanco site demonstrate that groundwater and surface water outside the site boundaries have not been affected by project-related contaminants.

  15. Factors controlling elevated lead concentrations in water samples from aquifer systems in Florida

    USGS Publications Warehouse

    Katz, B.G.; Bullen, M.P.; Bullen, T.D.; Hansard, Paul

    1999-01-01

    Concentrations of total lead (Pb) and dissolved Pb exceeded the U.S. Environmental Protection Agency action level of 15 micrograms per liter (mg/L) in approximately 19 percent and 1.3 percent, respectively, of ground-water samples collected during 1991-96 from a statewide network of monitoring wells designed to delineate background water quality of Florida's major aquifer systems. Differences in total Pb concentrations among aquifer systems reflect the combined influence of anthropogenic sources and chemical conditions in each system. A highly significant (p<0.001) difference in median total Pb concentrations was found for water samples from wells with water-level recording devices that contain Pb-counterweights (14 mg/L) compared to non-recorder wells (2 mg/L). Differences between total Pb concentrations for recorder and non-recorder wells are even more pronounced when compared for each aquifer system. The largest differences for recorder status are found for the surficial aquifer system, where median total Pb concentrations are 44 and 2.4 mg/L for recorder wells and non-recorder wells, respectively. Leaching of Pb from metal casing materials is another potential source of Pb in ground water samples. Median total Pb concentrations in water samples from the surficial, intermediate, and Floridan aquifer systems are higher from recorder wells cased with black iron than for recorder wells with steel and PVC casing material. Stable isotopes of Pb were used in this study to distinguish between anthropogenic and natural sources of Pb in ground water, as Pb retains the isotopic signature of the source from which it is derived. Based on similarities between slopes and intercepts of trend lines for various sample types (plots of 206Pb/204Pb versus 208Pb/204Pb and 207Pb/204Pb versus 208Pb/204Pb) the predominant source of total Pb in water samples from the surficial aquifer system is corrosion of Pb counterweights. It is likely that only ground-water samples, not the aquifer

  16. Water Column Sampling Capabilities of the NEPTUNE Canada Regional Cabled Observatory

    NASA Astrophysics Data System (ADS)

    Mihaly, S. F.; Neptune Canada Science

    2010-12-01

    The NEPTUNE Canada Regional Observatory affords a wide range of opportunities to conduct adaptive and high-temporal resolution water column property studies. Intensive sites are located in a shallow near-shore environment (Folger Passage), a shelf-slope-break region (Barkley Upper Slope) and a deep offshore mid-ocean spreading centre (Endeavour Ridge). The Folger Passage site has instrument platforms at 100 m and 23 m which are located near the mouth of Barkley Sound on the west coast of Vancouver Island. Instruments include upward-looking surface-wave resolving Acoustic Doppler Current Profilers (ADCPs), multi-frequency echo-sounders to measure backscatter from zooplankton and bottom pressure recorders to assess long-wave variability (e.g. tsunami, shelf waves, tidal). The near-bottom water column is sampled for salinity, temperature, oxygen, chlorophyll, turbidity, photosynthetically active light and, in addition, there are fine scale measurements of the velocity structure of the bottom-boundary layer. Water column measurements at the 400 metre deep Barkley Upper Slope site are facilitated by a world leading Vertical Profiling System (VPS). This winch operated system will profile a suite of instruments through the water column at up to 4 cycles per day. Optical measurements consist of a pair of hyperspectral radiometers to characterise downwelling irradiation and upwelling radiance, backscatter fluorescence for chlorophyll, and an optode to determine oxygen levels. A pumped CTD will provide salinity, temperature, depth as well as plumbing for a nitrate sensor, a coloured dissolved organic matter sensor and a pCO2 sensor. Acoustic instruments on the profiler consist of a 400 kHz ADCP, 200 kHz echosounder and a broad band hydrophone. With these instruments we expect to be able to explore the covariation of physical and chemical parameters with impact at a range of trophic levels, up to and including marine mammals. At the base of the VPS there is a long range ADCP

  17. 76 FR 7106 - Food Additives Permitted in Feed and Drinking Water of Animals; Formic Acid

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-09

    ... Drinking Water of Animals; Formic Acid AGENCY: Food and Drug Administration, HHS. ACTION: Final rule... in feed and drinking water of animals to provide for the safe use of formic acid as an acidifying... safe use of formic acid as an acidifying agent at levels not to exceed 1.2 percent in swine feed....

  18. Effects of holding time and measurement error on culturing Legionella in environmental water samples.

    PubMed

    Flanders, W Dana; Kirkland, Kimberly H; Shelton, Brian G

    2014-10-01

    Outbreaks of Legionnaires' disease require environmental testing of water samples from potentially implicated building water systems to identify the source of exposure. A previous study reports a large impact on Legionella sample results due to shipping and delays in sample processing. Specifically, this same study, without accounting for measurement error, reports more than half of shipped samples tested had Legionella levels that arbitrarily changed up or down by one or more logs, and the authors attribute this result to shipping time. Accordingly, we conducted a study to determine the effects of sample holding/shipping time on Legionella sample results while taking into account measurement error, which has previously not been addressed. We analyzed 159 samples, each split into 16 aliquots, of which one-half (8) were processed promptly after collection. The remaining half (8) were processed the following day to assess impact of holding/shipping time. A total of 2544 samples were analyzed including replicates. After accounting for inherent measurement error, we found that the effect of holding time on observed Legionella counts was small and should have no practical impact on interpretation of results. Holding samples increased the root mean squared error by only about 3-8%. Notably, for only one of 159 samples, did the average of the 8 replicate counts change by 1 log. Thus, our findings do not support the hypothesis of frequent, significant (≥= 1 log10 unit) Legionella colony count changes due to holding.

  19. Geophysical methods to support correct water sampling locations for salt dilution gauging

    NASA Astrophysics Data System (ADS)

    Comina, C.; Lasagna, M.; De Luca, D. A.; Sambuelli, L.

    2014-08-01

    To improve water management design, particularly in irrigation areas, it is important to evaluate the baseline state of the water resources, including canal discharge. Salt dilution gauging is a traditional and well-documented technique in this respect. The complete mixing of salt used for dilution gauging is required; this condition is difficult to test or verify and, if not fulfilled, is the largest source of uncertainty in the discharge calculation. In this paper, a geophysical technique (FERT, fast electrical resistivity tomography) is proposed for imaging the distribution of the salt plume used for dilution gauging at every point along a sampling cross section. With this imaging, complete mixing can be verified. If the mixing is not complete, the image created by FERT can also provide a possible guidance for selecting water-sampling locations in the sampling cross section. A water multi-sampling system prototype aimed to potentially take into account concentration variability is also proposed and tested. The results reported in the paper show that FERT provides a three-dimensional image of the dissolved salt plume and that this can potentially help in the selection of water sampling points.

  20. Electrothermal Vaporization Sample Introduction for Spaceflight Water Quality Monitoring via Gas Chromatography-Differential Mobility Spectrometry.

    PubMed

    Wallace, William T; Gazda, Daniel B; Limero, Thomas F; Minton, John M; Macatangay, Ariel V; Dwivedi, Prabha; Fernández, Facundo M

    2015-06-16

    In the history of manned spaceflight, environmental monitoring has relied heavily on archival sampling. However, with the construction of the International Space Station (ISS) and the subsequent extension in mission duration up to one year, an enhanced, real-time method for environmental monitoring is necessary. The station air is currently monitored for trace volatile organic compounds (VOCs) using gas chromatography-differential mobility spectrometry (GC-DMS) via the Air Quality Monitor (AQM), while water is analyzed to measure total organic carbon and biocide concentrations using the Total Organic Carbon Analyzer (TOCA) and the Colorimetric Water Quality Monitoring Kit (CWQMK), respectively. As mission scenarios extend beyond low Earth orbit, a convergence in analytical instrumentation to analyze both air and water samples is highly desirable. Since the AQM currently provides quantitative, compound-specific information for air samples and many of the targets in air are also common to water, this platform is a logical starting point for developing a multimatrix monitor. Here, we report on the interfacing of an electrothermal vaporization (ETV) sample introduction unit with a ground-based AQM for monitoring target analytes in water. The results show that each of the compounds tested from water have similar GC-DMS parameters as the compounds tested in air. Moreover, the ETV enabled AQM detection of dimethlsilanediol (DMSD), a compound whose analysis had proven challenging using other sample introduction methods. Analysis of authentic ISS water samples using the ETV-AQM showed that DMSD could be successfully quantified, while the concentrations obtained for the other compounds also agreed well with laboratory results.

  1. Towards a robust water content determination of freeze-dried samples by near-infrared spectroscopy.

    PubMed

    Grohganz, Holger; Gildemyn, Delphine; Skibsted, Erik; Flink, James M; Rantanen, Jukka

    2010-08-31

    The possibility for determination of the water content in pharmaceutical samples by near-infrared (NIR) spectroscopy has been more widely investigated in the past few years. However, many studies claim that changes in sample composition will require the establishment of a new method. The aim of this study was several fold: firstly to investigate validation aspects of water content determination in samples with varying composition and furthermore to see if a model based solely on freeze-dried mannitol-sucrose mixtures can be established that will be able to predict water contents for samples containing proteins, excipients or having a lower density of freeze-dried solids. Samples were measured by NIR, standard normal variate (SNV) corrected and the obtained spectra were compared with the results from a conventional Karl-Fischer titration by means of multivariate analysis, namely principal component analysis (PCA) and partial least square regression (PLS). For the overall sample set, a highly linear correlation between the NIR and the Karl-Fischer method with a slope of 1.00, an R(2) value of 0.98 and a root mean square error of cross-validation (RMSECV) of 0.15% were found. In a second step samples solely consisting of mannitol and sucrose mixtures were used to build a calibration set, which resulted in a RMSECV of 0.16%. The prediction of the remaining samples, which included protein or excipient containing samples, as well as lower density samples, resulted in a root mean square error of prediction (RMSEP) of 0.19%. Thus the present study demonstrated, that a general model for the determination of the water content by NIR could be established, within the limits investigated.

  2. 9 CFR 318.9 - Samples of products, water, dyes, chemicals, etc., to be taken for examination.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 9 Animals and Animal Products 2 2014-01-01 2014-01-01 false Samples of products, water, dyes... ESTABLISHMENTS; REINSPECTION AND PREPARATION OF PRODUCTS General § 318.9 Samples of products, water, dyes, chemicals, etc., to be taken for examination. Samples of products, water, dyes, chemicals,...

  3. 9 CFR 318.9 - Samples of products, water, dyes, chemicals, etc., to be taken for examination.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 9 Animals and Animal Products 2 2012-01-01 2012-01-01 false Samples of products, water, dyes... ESTABLISHMENTS; REINSPECTION AND PREPARATION OF PRODUCTS General § 318.9 Samples of products, water, dyes, chemicals, etc., to be taken for examination. Samples of products, water, dyes, chemicals,...

  4. 9 CFR 318.9 - Samples of products, water, dyes, chemicals, etc., to be taken for examination.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 9 Animals and Animal Products 2 2013-01-01 2013-01-01 false Samples of products, water, dyes... ESTABLISHMENTS; REINSPECTION AND PREPARATION OF PRODUCTS General § 318.9 Samples of products, water, dyes, chemicals, etc., to be taken for examination. Samples of products, water, dyes, chemicals,...

  5. Effect of water quality improvement on the remediation of river sediment due to the addition of calcium nitrate.

    PubMed

    Liu, Xiaoning; Tao, Yi; Zhou, Kuiyu; Zhang, Qiqi; Chen, Guangyao; Zhang, Xihui

    2017-01-01

    In situ sediment remediation technique is commonly used to control the release of pollutants from sediment. Addition of calcium nitrate to sediment has been applied to control the release of phosphorus from sediments. In this study, laboratory experiments were conducted to investigate the effect of water quality improvement on the remediation of river sediment with the addition of calcium nitrate. The results demonstrated that the redox-potential of sediments increased from -282mV to -130mV after 28days of calcium nitrate treatment. The acid volatile sulphide in the sediments significantly decreased (by 54.9% to 57.1%), whereas the total organic carbon decreased by 9.7% to 10.2%. However, the difference between these and water quality improvement was not significant. Due to the addition of calcium nitrate, low phosphate concentration in the water column and interstitial phosphate in the sediment were observed, indicating that the calcium nitrate was beneficial to controlling the release of phosphorus from river sediment. The decrease in phosphorus release could be attributed to the fixation of iron-phosphorus and calcium-phosphorus due to the addition of calcium nitrate. The addition of calcium nitrate to sediment caused the oxidation of sulphide to sulphate, hence resulting in high nitrate and sulphate concentrations in the water column, and high interstitial nitrate and sulphate concentrations in the sediment. The results also showed that only the water quality improvement had a significant effect on the interstitial nitrate and sulphate concentrations in the sediment.

  6. Cyto- and genotoxic potential of water samples from polluted areas in Kosovo.

    PubMed

    Alija, Avdulla J; Bajraktari, Ismet D; Bresgen, Nikolaus; Bojaxhi, Ekramije; Krenn, Margit; Asllani, Fisnik; Eckl, Peter M

    2016-09-01

    Reports on the state of the environment in Kosovo have emphasized that river and ground water quality is affected by pollution from untreated urban water as well as the waste water from the industry. One of the main contributors to this pollution is located in Obiliq (coal power plants). Prishtina-the capital city of Kosovo-is heavily influenced too. Furthermore, the pollutants combined together with those from heavy traffic are dissolved in Prishtina runoff water, which is discharged into the creek entering the river Sitnica together with urban waste water. The available data show the complex pollution with excessive quantities of nitrites, suspended materials, organic compounds, detergents, heavy metals, polychlorinated biphenyls, etc. In this study, the cytotoxic and genotoxic potential of water samples taken at these sites was tested in primary rat hepatocytes. The results obtained indicate that water samples collected in Prishtina and Obiliq had a significant cytotoxic potential in primary rat hepatocyte cultures even when diluted to 1 %. The increased cytotoxicity, however, was not accompanied by an increased genotoxicity as measured by the percentage of micronucleated cells. Further investigations addressing the chemical composition of the samples and the identification of the toxicants responsible for the cytotoxic effects found will be carried out in a next step.

  7. Monitoring water quality in Toronto's urban stormwater ponds: Assessing participation rates and data quality of water sampling by citizen scientists in the FreshWater Watch.

    PubMed

    Scott, Andrew B; Frost, Paul C

    2017-03-16

    From 2013 to 2015, citizen scientist volunteers in Toronto, Canada were trained to collect and analyze water quality in urban stormwater ponds. This volunteer sampling was part of the research program, FreshWater Watch (FWW), which aimed to standardize urban water sampling efforts from around the globe. We held training sessions for new volunteers twice yearly and trained a total of 111 volunteers. Over the course of project, ~30% of volunteers participated by collecting water quality data after the training session with 124 individual sampling events at 29 unique locations in Toronto, Canada. A few highly engaged volunteers were most active, with 50% of the samples collected by 5% of trainees. Stormwater ponds generally have poor water quality demonstrated by elevated phosphate concentrations (~30μg/L), nitrate (~427μg/L), and turbidity relative to Canadian water quality standards. Compared to other urban waterbodies in the global program, nutrient concentrations in Toronto's urban stormwater ponds were lower, while turbidity was not markedly different. Toronto FWW (FWW-TO) data was comparable to that measured by standard lab analyses and matched results from previous studies of stormwater ponds in Toronto. Combining observational and chemical data acquired by citizen scientists, macrophyte dominated ponds had lower phosphate concentrations while phytoplankton dominated ponds had lower nitrate concentrations, which indicates a potentially important and unstudied role of internal biogeochemical processes on pond nutrient dynamics. This experience in the FWW demonstrates the capabilities and constraints of citizen science when applied to water quality sampling. While analytical limits on in-field analyses produce higher uncertainty in water quality measurements of individual sites, rapid data collection is possible but depends on the motivation and engagement of the group of volunteers. Ongoing efforts in citizen science will thus need to address sampling effort

  8. Pilot study for U.S. Geological Survey Standard Reference Water Samples for pesticides

    USGS Publications Warehouse

    Friedman, L.C.; Fishman, M. J.; Boyle, D.K.

    1984-01-01

    The U. S. Geological Survey has been preparing and maintaining a library of standard reference water samples for inorganic constituents for 19 years. Recently, a pilot study was conducted to see if the reference-sample program could be expanded to include pesticides and other organic materials. Two samples containing organochlorine and organophosphorus insecticides, and chlorophenoxy acid herbicides were distributed to a number of laboratories in the United States. One of the samples also contained polychlorinated biphenyls. Interlaboratory data obtained from these round robin studies are presented with intralaboratory information on long-term stability.

  9. Locations of Sampling Stations for Water Quality Monitoring in Water Distribution Networks.

    PubMed

    Rathi, Shweta; Gupta, Rajesh

    2014-04-01

    Water quality is required to be monitored in the water distribution networks (WDNs) at salient locations to assure the safe quality of water supplied to the consumers. Such monitoring stations (MSs) provide warning against any accidental contaminations. Various objectives like demand coverage, time for detection, volume of water contaminated before detection, extent of contamination, expected population affected prior to detection, detection likelihood and others, have been independently or jointly considered in determining optimal number and location of MSs in WDNs. "Demand coverage" defined as the percentage of network demand monitored by a particular monitoring station is a simple measure to locate MSs. Several methods based on formulation of coverage matrix using pre-specified coverage criteria and optimization have been suggested. Coverage criteria is defined as some minimum percentage of total flow received at the monitoring stations that passed through any upstream node included then as covered node of the monitoring station. Number of monitoring stations increases with the increase in the value of coverage criteria. Thus, the design of monitoring station becomes subjective. A simple methodology is proposed herein which priority wise iteratively selects MSs to achieve targeted demand coverage. The proposed methodology provided the same number and location of MSs for illustrative network as an optimization method did. Further, the proposed method is simple and avoids subjectivity that could arise from the consideration of coverage criteria. The application of methodology is also shown on a WDN of Dharampeth zone (Nagpur city WDN in Maharashtra, India) having 285 nodes and 367 pipes.

  10. Relationship of land use to water quality in the Chesapeake Bay region. [water sampling and photomapping river basins

    NASA Technical Reports Server (NTRS)

    Correll, D. L.

    1978-01-01

    Both the proportions of the various land use categories present on each watershed and the specific management practices in use in each category affect the quality of runoff waters, and the water quality of the Bay. Several permanent and portable stations on various Maryland Rivers collect volume-integrated water samples. All samples are analyzed for a series of nutrient, particulate, bacterial, herbicide, and heavy metal parameters. Each basin is mapped with respect to land use by the analysis of low-elevation aerial photos. Analyses are verified and adjusted by ground truth surveys. Data are processed and stored in the Smithsonian Institution data bank. Land use categories being investigated include forests/old fields, pastureland, row crops, residential areas, upland swamps, and tidal marshes.

  11. Addition of a Magnetite Layer onto a Polysulfone Water Treatment Membrane to Enhance Virus Removal

    NASA Astrophysics Data System (ADS)

    Raciny, Isabel

    The applicability of low-pressure membranes systems in distributed (point of use) water treatment is hindered by, among other things, their inability to remove potentially harmful viruses and ions via size exclusion. According to the USEPA and the Safe Drinking Water Act, drinking water treatment processes must be designed for 4-log virus removal. Batch experiments using magnetite nanoparticle (nano-Fe3O4) suspensions and water filtration experiments with Polysulfone (PSf) membranes coated with nano-Fe3O 4 were conducted to assess the removal of a model virus (bacteriophage MS2). The membranes were coated via a simple filtration protocol. Unmodified membranes were a poor adsorbent for MS2 bacteriophage with less than 0.5-log removal, whereas membranes coated with magnetite nanoparticles exhibited a removal efficiency exceeding 99.99% (4-log). Thus, a cartridge of PSf membranes coated with nano-Fe3O4 particles could be used to remove viruses from water. Such membranes showed negligible iron leaching into the filtrate, thus obviating concern about colored water. Further research is needed to reduce the loss of water flux caused by coating.

  12. Addition of a magnetite layer onto a polysulfone water treatment membrane to enhance virus removal.

    PubMed

    Raciny, I; Zodrow, K R; Li, D; Li, Q; Alvarez, P J J

    2011-01-01

    The applicability of low-pressure membranes systems in distributed (point of use) water treatment is hindered by, among other things, their inability to remove potentially harmful viruses and ions via size exclusion. According to the USEPA and the Safe Drinking Water Act, drinking water treatment processes must be designed for 4-log virus removal. Batch experiments using magnetite nanoparticle (nano-Fe3O4) suspensions and water filtration experiments with polysulfone membranes coated with nano-Fe3O4 were conducted to assess the removal of a model virus (bacteriophage MS2). The membranes were coated via a simple filtration protocol. Unmodified membranes were a poor adsorbent for MS2 bacteriophage with less than 0.5-log removal, whereas membranes coated with magnetite nanoparticles exhibited a removal efficiency exceeding 99.99% (4-log). Thus, a cartridge of PSf membranes coated with nano-Fe3O4 particles could be used to remove viruses from water. Such membranes showed negligible iron leaching into the filtrate, thus obviating concern about coloured water. Further research is needed to reduce the loss of water flux caused by coating.

  13. Efficacy of the detection of Legionella in hot and cold water samples by culture and PCR. II. Examination of native samples from various sources.

    PubMed

    Stojek, Nimfa Maria; Wójcik-Fatla, Angelina; Dutkiewicz, Jacek

    2012-01-01

    A total of 123 water samples were examined in parallel by culture and semi-nested PCR for the presence of Legionella. They comprised: 35 samples of hot water distributed by the urban municipal water supply system (MWSS) taken in institutions, 45 samples of hot water distributed by urban MWSS taken in dwellings, 27 samples of cold water distributed by rural MWSS taken in dwellings, and 16 samples of cold well water taken in rural areas. The greatest frequency of the isolation of Legionella by culture (88.6%) was recorded in the samples of hot water from the urban institutions, having been greater compared to all other sources (p<0.001). The frequency of Legionella isolation from hot water in urban dwellings (28.9%) was significantly greater compared to the combined value (2.3%) for cold water from rural MWSS and wells (p<0.001). Strains belonging to Legionella pneumophila serogroups 2-14 predominated in the examined samples, while strains of L. pneumophila serogroup 1 and strains of Legionella spp. (other than L. pneumophila) were 3-fold less numerous. The rates of positive findings in the semi-nested PCR (stage 2) were greater than culture isolations in all kinds of samples, except for urban institutions. The correlation between the culture and PCR results was positive for samples of hot water from urban MWSS (p<0.01), but not for samples of cold water from rural MWSS and wells (p>0.5). A significant correlation was found between rates of PCR-positive results and numbers of Legionella pneumophila serogroups 2-14 strains, but not for other Legionella serogroups or species. In conclusion, our results support the opinion that though PCR cannot be a substitute for the isolation of Legionella by culture, it could be regarded as an useful complementary method.

  14. Highly efficient "on water" catalyst-free nucleophilic addition reactions using difluoroenoxysilanes: dramatic fluorine effects.

    PubMed

    Yu, Jin-Sheng; Liu, Yun-Lin; Tang, Jing; Wang, Xin; Zhou, Jian

    2014-09-01

    A remarkable fluorine effect on "on water" reactions is reported. The CF⋅⋅⋅HO interactions between suitably fluorinated nucleophiles and the hydrogen-bond network at the phase boundary of oil droplets enable the formation of a unique microstructure to facilitate on water catalyst-free reactions, which are difficult to realize using nonfluorinated substrates. Accordingly, a highly efficient on water, catalyst-free reaction of difluoroenoxysilanes with aldehydes, activated ketones, and isatylidene malononitriles was developed, thus leading to the highly efficient synthesis of a variety of α,α-difluoro-β-hydroxy ketones and quaternary oxindoles.

  15. Methods for primary concentration of viruses from water samples: a review and meta-analysis of recent studies.

    PubMed

    Cashdollar, J L; Wymer, L

    2013-07-01

    Since the beginning of environmental virology in the mid-twentieth century, a key challenge to scientists in the environmental field has been how to collect, isolate and detect pathogenic viruses from water that is used for drinking and/or recreational purposes. Early studies investigated different types of membrane filters, with more sophisticated technologies being developed more recently. The purpose of this study was to look at the current state of the science of methods for the concentration of viruses from water. Several technologies were reviewed, and associated data were included in a meta-analysis which showed that electronegative filters, electropositive filters and ultrafilters are comparable in performance and that significant differences in recovery are due to virus type rather than filter type, water matrix or sample volume. This information is useful, as it will help to determine which method(s) should be used, particularly if there is a specific viral type being targeted for a particular study. In addition, it will be helpful when sampling different environmental water matrices and/or when budget allowance must be taken into consideration. Taken together, this will be useful in performing viral occurrence studies, which ultimately can help ensure safer water for both humans and the environment.

  16. Concentration and Detection of Caliciviruses in Water Samples by Reverse Transcription-PCR

    PubMed Central

    Huang, P. W.; Laborde, D.; Land, V. R.; Matson, D. O.; Smith, A. W.; Jiang, X.

    2000-01-01

    Human caliciviruses (HuCVs) cause waterborne outbreaks of gastroenteritis. Standard indicators of a safe water supply do not adequately predict contamination of water by viruses, including HuCVs. We developed a method to concentrate and detect HuCVs in water samples by using a cultivable primate calicivirus (Pan-1) as a model. Viable Pan-1 was seeded in different types of water and then filtered with a 1MDS filter, eluted with beef extract (BE), and reconcentrated by polyethylene glycol (PEG) precipitation. The viruses in the final samples were tested by plaque assay or by reverse transcription (RT)-PCR following extraction of the RNA with Trizol. Pan-1 was more sensitive to high-pH treatment than poliovirus was; a pH 9.0 BE solution was found to recover 35% more viable Pan-1 than a pH 9.5 BE solution recovered. Pan-1 was recovered from small volumes of deionized, finished, ground, and surface waters at efficiencies of 94, 73, 67, and 64%, respectively, when samples were assayed after elution without further concentration. When larger volumes of water (up to 40 liters) were tested after elution and concentration with PEG, 38, 19, and 14% of the seeded Pan-1 were recovered from finished, ground, and surface waters, respectively. The limit of detection of Pan-1 by RT-PCR was estimated to be 0.75 to 1.5 PFU in 40 liters of finished water. This method may be adapted for monitoring HuCVs in drinking water and other types of water for public health safety. PMID:11010887

  17. Using SPMDs for monitoring hydrophobic organic compounds in urban river water in Korea compared with using conventional water grab samples

    USGS Publications Warehouse

    Kim, Un-Jung; Kim, Hee Young; Alvarez, David A.; Lee, In-Seok; Oh, Jeong-Eun

    2014-01-01

    We aimed to verify the effectiveness of semi-permeablemembrane devices (SPMDs) formonitoring hydrophobic organic compounds, such as polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs), that are not easy to detect using conventional grab samples (because of their low concentrations), in water.We used SPMDs and grab samples to monitor PCBs and PBDEs upstream and downstream of a sewage treatment plant (STP) in the Suyeong River in Busan, Korea. Concentrations in three different phases (freely dissolved, apparently dissolved, and particulate) were measured, to investigate the aquatic fate of PCBs and PBDEs. The freely dissolved (SPMD) concentrations were 2–3 times higher than the apparently dissolved and particulate phase (grab sample) concentrations. No meaningful relationships were found between the total PCB and PBDE concentrations of the grab sample and SPMD sample because of the different partitioning behaviors and detection frequencies of the individual chemicals. However, the summed concentrations of specific PCB and PBDE congeners (that were abundant in all samples) in the grab and SPMD samples correlated well (r2 = 0.7451 for PCBs 28 + 52 + 153, r2 = 0.9987 for PBDEs 28 + 47 + 99). The PBDE concentrations measured using SPMDs decreased with increasing distance from the STP, but no apparent dilution effect was found in the grab samples. Our results show that SPMDs could be used to support grab sampling for specific chemicals, or to trace chemical sources (such as STPs) to the aquatic environment.

  18. Field guide for collecting and processing stream-water samples for the National Water-Quality Assessment Program

    USGS Publications Warehouse

    Shelton, Larry R.

    1994-01-01

    The U.S. Geological Survey's National Water-Quality Assessment program includes extensive data- collection efforts to assess the quality of the Nations's streams. These studies require analyses of stream samples for major ions, nutrients, sediments, and organic contaminants. For the information to be comparable among studies in different parts of the Nation, consistent procedures specifically designed to produce uncontaminated samples for trace analysis in the laboratory are critical. This field guide describes the standard procedures for collecting and processing samples for major ions, nutrients, organic contaminants, sediment, and field analyses of conductivity, pH, alkalinity, and dissolved oxygen. Samples are collected and processed using modified and newly designed equipment made of Teflon to avoid contamination, including nonmetallic samplers (D-77 and DH-81) and a Teflon sample splitter. Field solid-phase extraction procedures developed to process samples for organic constituent analyses produce an extracted sample with stabilized compounds for more accurate results. Improvements to standard operational procedures include the use of processing chambers and capsule filtering systems. A modified collecting and processing procedure for organic carbon is designed to avoid contamination from equipment cleaned with methanol. Quality assurance is maintained by strict collecting and processing procedures, replicate sampling, equipment blank samples, and a rigid cleaning procedure using detergent, hydrochloric acid, and methanol.

  19. A continuous water sampling and multi-parameter measurement system for estuaries

    USGS Publications Warehouse

    Schemel, Laurence E.; Dedini, Lee A.

    1979-01-01

    Salinity, temperature, light transmissivity, oxygen saturation, turbidity, pH, pCO2, and chlorophyll a fluorescence of a pumped water sample are continuously measured with a system designed primarily for estuarine studies. Near-surface water from a depth of 2 m is sampled continuously while the vessel is underway or water at depths to 100 m can be collected with an in situ pump, in which case the sampling depth and temperature are measured by an in situ probe. The system is comprised of commercially available instruments, equipment, and components, and of specialized items designed and fabricated by the authors. Data can be read from digital displays and analog strip-chart recorders. Tables and figures describing specialized items are included.

  20. QUANTITATIVE VS. CONVENTIONAL PCR FOR DETECTION OF HUMAN ADENOVIRUSES IN WATER AND SEDIMENT SAMPLES

    PubMed Central

    STAGGEMEIER, Rodrigo; BORTOLUZZI, Marina; HECK, Tatiana Moraes da Silva; SPILKI, Fernando Rosado; ALMEIDA, Sabrina Esteves de Matos

    2015-01-01

    SUMMARY Human Adenoviruses (HAdV) are notably resistant in the environment. These agents may serve as effective indicators of fecal contamination, and may act as causative agents of a number of different diseases in human beings. Conventional polymerase chain reaction (PCR) and, more recently, quantitative PCR (qPCR) are widely used for detection of viral agents in environmental matrices. In the present study PCR and SYBR(r)Green qPCR assays were compared for detection of HAdV in water (55) and sediments (20) samples of spring and artesian wells, ponds and streams, collected from dairy farms. By the quantitative methodology HAdV were detected in 87.3% of the water samples and 80% of the sediments, while by the conventional PCR 47.3% and 35% were detected in water samples and sediments, respectively. PMID:26422153

  1. QUANTITATIVE VS. CONVENTIONAL PCR FOR DETECTION OF HUMAN ADENOVIRUSES IN WATER AND SEDIMENT SAMPLES.

    PubMed

    Staggemeier, Rodrigo; Bortoluzzi, Marina; Heck, Tatiana Moraes da Silva; Spilki, Fernando Rosado; Almeida, Sabrina Esteves de Matos

    2015-01-01

    Human Adenoviruses (HAdV) are notably resistant in the environment. These agents may serve as effective indicators of fecal contamination, and may act as causative agents of a number of different diseases in human beings. Conventional polymerase chain reaction (PCR) and, more recently, quantitative PCR (qPCR) are widely used for detection of viral agents in environmental matrices. In the present study PCR and SYBR(r)Green qPCR assays were compared for detection of HAdV in water (55) and sediments (20) samples of spring and artesian wells, ponds and streams, collected from dairy farms. By the quantitative methodology HAdV were detected in 87.3% of the water samples and 80% of the sediments, while by the conventional PCR 47.3% and 35% were detected in water samples and sediments, respectively.

  2. Guidance document for preparing water sampling and analysis plans for UMTRA sites. Final [report

    SciTech Connect

    Not Available

    1993-09-01

    A water sampling and analysis plan (WSAP) is required for each Uranium Mill Tailings Remedial Action (UMTRA) site to provide rationale for groundwater and surface water sampling at disposal sites and former processing sites. The WSAP identifies and justifies the sampling locations, analytical parameters, detection limits, and sampling frequencies for the groundwater and surface water monitoring stations at each site. Section 2.0 of this WSAP Guidance Document describes the WSAP format. Sections 3.0 and 4.0 provide guidance for selecting sampling frequencies and sampling locations, respectively. Section 5.0 contains criteria for selecting analytical parameters. Section 6.0 provides guidance for the contents of each site`s WSAP file. Finally, Section 7.0 presents the references used to prepare this document. The purpose of this guidance document is to provide a consistent technical approach for sampling and monitoring activities performed under WSAPs and a consistent format for WSAP documents. This document is designed for use by the Technical Assistance Contractor (TAC) to prepare WSAPs and by the US Department of Energy (DOE), Nuclear Regulatory Commission, state and tribal agencies, regulatory agencies, and the public to evaluate the contents of the WSAPS. This guidance document may be updated periodically based on new or changing regulations.

  3. Active Sampling Device for Determining Pollutants in Surface and Pore Water – the In Situ Sampler for Biphasic Water Monitoring

    NASA Astrophysics Data System (ADS)

    Supowit, Samuel D.; Roll, Isaac B.; Dang, Viet D.; Kroll, Kevin J.; Denslow, Nancy D.; Halden, Rolf U.

    2016-02-01

    We designed and evaluated an active sampling device, using as analytical targets a family of pesticides purported to contribute to honeybee colony collapse disorder. Simultaneous sampling of bulk water and pore water was accomplished using a low-flow, multi-channel pump to deliver water to an array of solid-phase extraction cartridges. Analytes were separated using either liquid or gas chromatography, and analysis was performed using tandem mass spectrometry (MS/MS). Achieved recoveries of fipronil and degradates in water spiked to nominal concentrations of 0.1, 1, and 10 ng/L ranged from 77 ± 12 to 110 ± 18%. Method detection limits (MDLs) were as low as 0.040–0.8 ng/L. Extraction and quantitation of total fiproles at a wastewater-receiving wetland yielded concentrations in surface water and pore water ranging from 9.9 ± 4.6 to 18.1 ± 4.6 ng/L and 9.1 ± 3.0 to 12.6 ± 2.1 ng/L, respectively. Detected concentrations were statistically indistinguishable from those determined by conventional, more laborious techniques (p > 0.2 for the three most abundant fiproles). Aside from offering time-averaged sampling capabilities for two phases simultaneously with picogram-per-liter MDLs, the novel methodology eliminates the need for water and sediment transport via in situ solid phase extraction.

  4. Active Sampling Device for Determining Pollutants in Surface and Pore Water – the In Situ Sampler for Biphasic Water Monitoring

    PubMed Central

    Supowit, Samuel D.; Roll, Isaac B.; Dang, Viet D.; Kroll, Kevin J.; Denslow, Nancy D.; Halden, Rolf U.

    2016-01-01

    We designed and evaluated an active sampling device, using as analytical targets a family of pesticides purported to contribute to honeybee colony collapse disorder. Simultaneous sampling of bulk water and pore water was accomplished using a low-flow, multi-channel pump to deliver water to an array of solid-phase extraction cartridges. Analytes were separated using either liquid or gas chromatography, and analysis was performed using tandem mass spectrometry (MS/MS). Achieved recoveries of fipronil and degradates in water spiked to nominal concentrations of 0.1, 1, and 10 ng/L ranged from 77 ± 12 to 110 ± 18%. Method detection limits (MDLs) were as low as 0.040–0.8 ng/L. Extraction and quantitation of total fiproles at a wastewater-receiving wetland yielded concentrations in surface water and pore water ranging from 9.9 ± 4.6 to 18.1 ± 4.6 ng/L and 9.1 ± 3.0 to 12.6 ± 2.1 ng/L, respectively. Detected concentrations were statistically indistinguishable from those determined by conventional, more laborious techniques (p > 0.2 for the three most abundant fiproles). Aside from offering time-averaged sampling capabilities for two phases simultaneously with picogram-per-liter MDLs, the novel methodology eliminates the need for water and sediment transport via in situ solid phase extraction. PMID:26905924

  5. Additivity of water sorption, alpha-relaxations and crystallization inhibition in lactose-maltodextrin systems.

    PubMed

    Potes, Naritchaya; Kerry, Joseph P; Roos, Yrjö H

    2012-08-01

    Water sorption of lactose-maltodextrin (MD) systems, structural relaxations and lactose crystallization were studied. Accurate water sorption data for non-crystalline lactose previously not available over a wide range of water activity, aw (<0.76aw) were derived from lactose-MD systems data. Structural relaxations and crystallization of lactose in lactose-maltodextrin (MD) systems were strongly affected by water and MD. At high MD contents, inhibition of crystallization was significant. Inhibition with a high dextrose equivalent (DE) MD was more pronounced possibly because of molecular number and size effects. At 0.55-0.76aw, inhibition increased with increasing MD content. At aw>0.66, the rate of lactose crystallization decreased at increasing MD contents. Different MDs with similar Tg in lacto