WorldWideScience

Sample records for rinse water discharged

  1. Optimal design of zero-water discharge rinsing systems.

    Science.gov (United States)

    Thöming, Jorg

    2002-03-01

    This paper is about zero liquid discharge in processes that use water for rinsing. Emphasis was given to those systems that contaminate process water with valuable process liquor and compounds. The approach involved the synthesis of optimal rinsing and recycling networks (RRN) that had a priori excluded water discharge. The total annualized costs of the RRN were minimized by the use of a mixed-integer nonlinear program (MINLP). This MINLP was based on a hyperstructure of the RRN and contained eight counterflow rinsing stages and three regenerator units: electrodialysis, reverse osmosis, and ion exchange columns. A "large-scale nickel plating process" case study showed that by means of zero-water discharge and optimized rinsing the total waste could be reduced by 90.4% at a revenue of $448,000/yr. Furthermore, with the optimized RRN, the rinsing performance can be improved significantly at a low-cost increase. In all the cases, the amount of valuable compounds reclaimed was above 99%.

  2. RECYCLING NICKEL ELECTROPLATING RINSE WATERS BY LOW TEMPERATURE EVAPORATION AND REVERSE OSMOSIS

    Science.gov (United States)

    Low temperature evaporation and reverse osmosis systems were each evaluated (on a pilot scale) on their respective ability to process rinse water collected from a nickel electroplating operation. Each system offered advantages under specific operating conditions. The low temperat...

  3. Prebrushing rinse with water on plaque removal: a split-mouth design.

    Science.gov (United States)

    Van der Sluijs, E; Slot, D E; Hennequin-Hoenderdos, N L; Van Leeuwen, Mpc; Van der Weijden, G A

    2017-11-01

    The aim was to evaluate whether there is an additional beneficial effect on dental plaque removal of rinsing the oral cavity with water before toothbrushing. In total, 48 non-dental, systemically healthy participants ≥18 years were included in this randomized controlled clinical trial using a split-mouth design. The participants were requested to refrain from any form of oral hygiene for 48 h. First dental plaque scores (PI) were assessed full mouth. Two randomly assigned contra-lateral quadrants were brushed. Next the participant rinsed for 1 min with 15 ml water. Subsequently, the opposite two contra-lateral quadrants were brushed. Brushing was performed without toothpaste. Subsequently the second full-mouth PI assessment was performed. The brushing and rinsing procedure was performed under supervision and brushing time was tracked by a timer, each quadrant was brushed for 30 s. For the buccal, lingual, and approximal surfaces and tooth type, a subanalysis was performed. At baseline there was no statistically significantly difference between the two sets of contra-lateral quadrants. When a water rinse was used before toothbrushing the PI-score was reduced by 58%. If water rinse was used post-brushing the PI-score reduced by 57%. The difference of 0.04 in mean plaque index score reduction between the two brushing regimens was not significant(P = 0.162). When a 2 min brushing exercise was performed, on average more than 55% dental plaque was removed. Prerinsing with water did not contribute significantly to toothbrush efficacy. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  4. Ion exchange treatment of rinse water generated in the galvanizing process.

    Science.gov (United States)

    Marañón, Elena; Fernández, Yolanda; Castrillón, Leonor

    2005-01-01

    A study was conducted of the viability of using the cationic exchange resins Amberlite IR-120 and Lewatit SP-112 to treat rinse water generated in the galvanizing process as well as acidic wastewater containing zinc (Zn) and iron (Fe). Solutions containing either 100 mg/L of Zn at pH 5.6 (rinse water) or Fe and Zn at concentrations of 320 and 200 mg/L at pH 1.5 (acidic water), respectively, were percolated through packed beds until the resins were exhausted. Breakthrough capacities obtained ranged between 1.1 and 1.5 meq metal/mL resin. The elution of metal and the regeneration of resins were performed with hydrochloric acid. The influence of the flowrate used during the loading stage was also studied, with 0.5 bed volumes/min (3.2 cm/min) found to be the optimum flowrate.

  5. The relationship between turbidity of mouth-rinsed water and oral health status.

    Science.gov (United States)

    Takeuchi, Susumu; Ueno, Masayuki; Takehara, Sachiko; Pham, Thuy Anh Vu; Hakuta, Chiyoko; Morishima, Seiji; Shinada, Kayoko; Kawaguchi, Yoko

    2013-01-01

    The purpose of this study was to examine the relationship between turbidity of mouth rinsed water and oral health status such as dental and periodontal conditions, oral hygiene status, flow rate of saliva and oral bacteria. Subjects were 165 patients who visited the Dental Hospital, Tokyo Medical and Dental University. Oral health status, including dental and periodontal conditions, oral hygiene status and flow rate of saliva, was clinically examined. The turbidity was measured with a turbidimeter. Quantification of Fusobacterium spp, Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola and total bacteria levels was performed using real-time PCR. The Pearson correlation and multiple regression analysis were used to explore the associations between the turbidity and oral health parameters. The turbidity showed significant correlations with the number of decayed teeth and deep pockets, the plaque index, extent of tongue coating and Fusobacterium spp, P. gingivalis, T. forsythia, T. denticola and total bacteria levels. In a multiple regression model, the turbidity was negatively associated with the flow rate of saliva and positively associated with the total number of bacteria (p turbidity of mouth rinsed water could be used as an indicator to evaluate oral health condition and the amount of bacteria in the oral cavity. In addition, the turbiditimeter appeared as a simple and objective device for screening abnormality of oral health condition at chair side as well as community-based research.

  6. Removal of nickel from electroplating rinse waters using electrostatic shielding electrodialysis/electrodeionization.

    Science.gov (United States)

    Dermentzis, Konstantinos

    2010-01-15

    Electrostatic shielding zones made of electrode graphite powder were used as a new type of ionic and electronic current sinks. Because of the local elimination of the applied electric field, voltage and current within the zones, ions are led inside them and accumulate there. The current sinks were implemented in electrostatic shielding electrodialysis of a simulated nickel plating rinse water containing 100 mg L(-1) nickel and electrodeionization of a 0.001 M NiSO(4) solution with simultaneous electrochemical regeneration of the ion exchange resin beds. Pure water was obtained with a Ni(2+) ion concentration of less than 0.1 mg L(-1) at a flow rate of 2.02 x 10(-4)dm(3)s(-1) diluate stream and a current density of 30 Am(-2).

  7. Diffusion of condenser water discharge

    International Nuclear Information System (INIS)

    Iwakiri, Toshio

    1977-01-01

    Thermal and nuclear power stations in Japan are mostly located in coastal area, and the cooling water is discharged into sea as warm water. Recently, large interest is taken in this matter, and it is desirable to predict the diffusion of warm discharge accurately and to take effective measures for lowering the temperature. As for the methods of predicting the diffusion of warm discharge, simplified estimation, mathematical analysis and hydrographical model experiment are used corresponding to objects and conditions. As for the measures to lower temperature, the method of discharging warm water into deep sea bottom was confirmed to be very effective. In this paper, the phenomena of diffusion of warm discharge in sea, the methods of predicting the diffusion of warm discharge, and the deep sea discharge as the measure for lowering temperature are outlined. The factors concerning the diffusion of warm discharge in sea are the conditions of discharge, topography and sea state, and the diffusion is roughly divided into mixing diffusion in the vicinity of warm water outlet and eddy diffusion in distant region. It is difficult to change artificially the conditions of diffusion in distant region, and the measures of raising the rate of dilution in near region are effective, therefore the deep sea discharge is adopted. (Kako, I.)

  8. Mouth Rinses

    Science.gov (United States)

    ... with more severe oral problems, such as cavities, periodontal disease, gum inflammation, and xerostomia (dry mouth). Therapeutic ... fight up to 50 percent more of the bacteria that cause cavities, and most rinses are effective ...

  9. Tomato type and post-treatment water rinse affect efficacy of acid washes against Salmonella enterica inoculated on stem scars of tomatoes and product quality.

    Science.gov (United States)

    Fan, Xuetong; Gurtler, Joshua B; Sokorai, Kimberly J B

    2018-09-02

    A study was conducted to evaluate the effects of post-treatment rinsing with water on the inactivation efficacy of acid treatments against Salmonella inoculated onto stem scar areas of two types of tomatoes. In addition, impact on fruit quality was investigated during 21 days post-treatment storage at 10 °C. A four-strain cocktail of Salmonella enterica (S. Montevideo, S. Newport, S. Saintpaul, and S. Typhimurium) was inoculated onto stem scar areas of grape and large round tomatoes. The inoculated fruits were then treated for 2 min with the following solutions: water, 2% lactic acid +2% acetic acid +2% levulinic acid, 1.7% lactic acid +1.7% acetic acid +1.7% levulinic acid, and 3% lactic acid +3% acetic acid. After treatments, half of the fruits were rinsed with water while another half were not rinsed. Non-inoculated grape tomatoes for quality analysis were treated with the same solutions with and without subsequent water rinse. Results demonstrated that the acid combinations reduced populations of Salmonella enterica on the stem scar area of grape tomatoes by 1.52-1.90 log CFU/fruit, compared with the non-treated control while water wash and rinse removed the bacterium by only 0.23-0.30 log CFU/fruit. On the stem scar of large round tomatoes, the same acid treatments achieved 3.54 log CFU/fruit reduction of the pathogen. The varying response to the acid washes between grape and large round tomatoes seems to be related to the differences in surface characteristics of stem scar areas observed with SEM. Rinsing with water after acid combination treatments did not significantly affect the efficacy of the treatments in either grape or large round tomatoes. Acidic off-odor was detected on fruits treated with acid combination without water rinse 1 day after treatment while water rinse eliminated the off-odor. The acid treatments with and without water rinse did not consistently affect appearance, color, firmness, or lycopene or ascorbic acid contents of

  10. Waste water discharges into natural waters

    International Nuclear Information System (INIS)

    Marri, P.; Barsanti, P.; Mione, A.; Posarelli, M.

    1996-12-01

    The aqueous discharges into natural waters is a very technical solution expecially for surface buoyant discharges. It is not only convenient to limit the concentration levels of the discharges, but also to improve the turbolent processes that diluite the discharge. Mostly these processes depend by some geometric parameters of the discharge and by some physical parameters of the effluent and of the receiving water body. An appropriate choice of some parameters, using also suitable mathematical models, allows to design discharges with a very high dilution; so the decreasing of the pollutant levels is improved and the environmental impact can be reduced versus a not diluted effluent. The simulations of a mathematical model, here described, prove that in some circumstances, expecially in case of discharges of fresh water into saline water bodies with a low velocity of the current, the dilution is poor; the effluent can be trapped in a narrow water surface layer where the pollutant concentrations remain high. also far away from the discharge point

  11. Viability of sublethally injured coliform bacteria on fresh-cut cabbage stored in high CO2 atmospheres following rinsing with electrolyzed water.

    Science.gov (United States)

    Izumi, Hidemi; Inoue, Ayano

    2018-02-02

    The extent of sublethally injured coliform bacteria on shredded cabbage, either rinsed or not rinsed with electrolyzed water, was evaluated during storage in air and high CO 2 controlled atmospheres (5%, 10%, and 15%) at 5°C and 10°C using the thin agar layer (TAL) method. Sublethally injured coliform bacteria on nonrinsed shredded cabbage were either absent or they were injured at a 64-65% level when present. Rinsing of shredded cabbage with electrolyzed water containing 25ppm available chlorine reduced the coliform counts by 0.4 to 1.1 log and caused sublethal injury ranging from 42 to 77%. Pantoea ananatis was one of the species injured by chlorine stress. When shredded cabbage, nonrinsed or rinsed with electrolyzed water, was stored in air and high CO 2 atmospheres at 5°C for 7days and 10°C for 5days, coliform counts on TAL plates increased from 3.3-4.5 to 6.5-9.0 log CFU/g during storage, with the increase being greater at 10°C than at 5°C. High CO 2 of 10% and 15% reduced the bacterial growth on shredded cabbage during storage at 5°C. Although injured coliform bacteria were not found on nonrinsed shredded cabbage on the initial day, injured coliforms at a range of 49-84% were detected on samples stored in air and high CO 2 atmospheres at 5°C and 10°C. Injured cells were detected more frequently during storage at both temperatures irrespective of the CO 2 atmosphere when shredded cabbage was rinsed with electrolyzed water. These results indicated that injured coliform bacteria on shredded cabbage, either rinsed or not rinsed with electrolyzed water, exhibited different degrees of injury during storage regardless of the CO 2 atmosphere and temperature tested. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. The use of a rotating cylinder electrode to recover zinc from rinse water generated by the electroplating industry.

    Science.gov (United States)

    Matlalcuatzi, Sairi; Nava, José L

    2012-01-01

    This work concerns the application of a laboratory scale rotating cylinder electrode (RCE) to recover zinc from rinse water generated by the electrolytic zinc process (initially 1,300, 4,400, 50, 20 mg L(-1) of Zn(II), Fe(III), Ag(I) and Cr(VI), respectively, at pH 2), although it is also applicable to other electroplating industries. Experimental results demonstrated the convenience of the removal of ferric ions, as (Fe(OH)(3(s))) by a pH adjustment to 4, before zinc electro recovery on the RCE. The generation of smooth zinc deposits on the RCE was obtained at Reynolds numbers within the range of 15,000 ≤ Re ≤ 124,000 and limiting current densities (J(L)) in the interval of -4.8 to -13 mA cm(-2). The zinc recovery reached a conversion of 67% in 90 min of electrolysis for Re = 124,000 and J = -13 mA cm(-2), 21% current efficiency, and energy consumption of 9.5 kWh m(-3). The treated solution can be recycled back through the same rinsing process.

  13. Microbiological Evaluation of Broiler Carcasses, Wash and Rinse Water from Pluck Shops (Cottage Poultry Processors in the County Nariva/Mayaro, Trinidad, Trinidad and Tobago, West Indies

    Directory of Open Access Journals (Sweden)

    Thomas, A.

    2006-01-01

    Full Text Available A study on the prevalence and levels of Campylobacter, Salmonella and E. coli on broiler chicken carcasses, wash and rinse water from pluck shops/ cottage poultry processors (CPP in county Nariva Mayaro Trinidad was done. There are 21 pluck shops/ cottage poultry processors in the county, 14 pluck shops were randomly selected for the study. Samples consisted of 28 broiler carcasses, 14 wash water samples and 14 rinse water samples. Over all the isolation rate of Campylobacter, Salmonella and E. coli from broiler carcasses wash and rinse water showed significant differences (P< 0.05 between pluck shops. Of the 56 samples examined from the 14 pluck shops sampled, 34 (60.7% were positive for Campylobacter, 34 (60.7% for Salmonella and 40 (71.4% for E. coli. The correlation between the levels of Campylobacter found on carcasses and in wash water (r2= 0.657 and rinse water (r2= 0.600 was significant (P< 0.05 among pluck shops/CPP. There was also a high correlation (P< 0.05 between wash and rinse water samples (r2= 0.950 for Campylobacter. Salmonella levels on carcasses and in wash water were positively (P< 0.05 correlated (r2= 0.947. Of the 14 pluck shops examined 6 (42.9% had Campylobacter levels that corresponded to infectious dose in humans. The infectious doses for Salmonella were isolated from 3 (21.4% pluck shops and 13 (92.9% pluck shops evaluated had E. coli present at potentially infectious levels. Three pluck shops/CPP (21.4% had infectious dose for Campylobacter, Salmonella and E. coli where as all others had infectious levels for one or two pathogens. It was concluded that these pathogens are present in pluck shops/CPP in the county, having levels considered to be potentially infectious to humans and as such there should be health concern.

  14. Re-use of laundry rinsing water by low cost adsorption technology

    NARCIS (Netherlands)

    Schouten, N.

    2009-01-01

    Shortage of water is a growing global problem. One way of dealing with this problem is the development of technologies for wastewater clean-up and re-use. Laundry accounts often for more than half of the daily domestic water consumption in countries like India. The major part of laundry water is

  15. Daylong Effect of Rinsing with Water Diluted Antiplaque®Toothpaste Combined with Toothbrushing on Volatile Sulphur Compound Levels

    Directory of Open Access Journals (Sweden)

    Anandina Irmagita

    2013-07-01

    Full Text Available Halitosis, complained by most adult population, is a common oral condition. About 8%% of the cases happened because of the microbia activity in the oral cavity that produces Volatile Sulphur Compound (VSC which has unpleasant odour. Daily oral prophylaxis can reduce the oral VSC levels. Objective: to determine the daylong effect of Antiplque® toothpaste in daily oral prophylaxis: as dentrifice for tooth brushing and, in modified way, as oral rinse; on the VSC level. Methods: a double blind, clinical experimental study, involving 120 subjects with or without halitosis complain, divided in 2 treatment groups (oral rinse group and the combination of tooth brushing and oral rinse group, using Antiplaque® toothpaste and 2 control groups (same procedure using placebo toothpaste. The daylong VSC levels measure with halimeter were taken twice, in the afternoon day I and day II. Results: there are significant reduction of daylong VSC levels (Wilcoxon signed rank test P<0.0%, but not in the treatment groups using the placebo toothpaste. The result on conbination of tooth brushing and oral rinse using Antiplaque® toothpaste are significant compared to the oral rinse treatment using Antiplaque® toothpaste alone (Mann Whitney, P<0.05. Conclusion: tooth brushing with Antiplaque® toothpaste combined with oral rinse using the modified Antiplaque® toothpaste can significantly reduce daylong VSC levels.DOI: 10.14693/jdi.v16i2.94

  16. Comparative evaluation of mouth rinsing with plain water and an antibacterial mouth rinse on salivary pH: A randomized clinical trial

    OpenAIRE

    Shweta Singh; P Anuradha; S Sahana; Manu Narayan; Sugandha Agarwal

    2017-01-01

    Introduction: Salivary pH plays an important role in maintaining oral health and in particular affecting dental caries. Studies have confirmed the antibacterial beneficial effects of chlorhexidine on dental health by increasing salivary pH (changing acidic pH to more neutral pH). Water, the most precious/omnipresent liquid also bears an effect on salivary pH. Materials and Methods: A double-blind concurrent parallel study design was employed on 40 individuals to evaluate changes in salivary p...

  17. State waste discharge permit application for cooling water and condensate discharges

    Energy Technology Data Exchange (ETDEWEB)

    Haggard, R.D.

    1996-08-12

    The following presents the Categorical State Waste Discharge Permit (SWDP) Application for the Cooling Water and Condensate Discharges on the Hanford Site. This application is intended to cover existing cooling water and condensate discharges as well as similar future discharges meeting the criteria set forth in this document.

  18. Influence of discharged effluent on the quality of surface water ...

    African Journals Online (AJOL)

    SERVER

    2007-10-04

    Oct 4, 2007 ... “treated” effluents from the Percy Stewart waste treatment plant and the mine ... washed with detergent, rinsed with water and then with distilled .... S = sampling point, w. = water sample, s = sediment sample. 0.01. 0.1. 1. 10. 100. 1000. S1w. S1s. S2w. S2s. S3w. S3s. Sampling sites. C o n c. (m g. /l a n d u g.

  19. Modacrylic anion-exchange fibers for Cr(VI) removal from chromium-plating rinse water in batch and flow-through column experiments.

    Science.gov (United States)

    Lee, Seung-Chan; Kang, Jin-Kyu; Sim, Eun-Hye; Choi, Nag-Choul; Kim, Song-Bae

    2017-11-10

    The aim of this study was to investigate Cr(VI) removal from chromium-plating rinse water using modacrylic anion-exchange fibers (KaracaronTM KC31). Batch experiments were performed with synthetic Cr(VI) solutions to characterize the KC31 fibers in Cr(VI) removal. Cr(VI) removal by the fibers was affected by solution pH; the Cr(VI) removal capacity was the highest at pH 2 and decreased gradually with a pH increase from 2 to 12. In regeneration and reuse experiments, the Cr(VI) removal capacity remained above 37.0 mg g -1 over five adsorption-desorption cycles, demonstrating that the fibers could be successfully regenerated with NaCl solution and reused. The maximum Cr(VI) removal capacity was determined to be 250.3 mg g -1 from the Langmuir model. In Fourier-transform infrared spectra, a Cr = O peak newly appeared at 897 cm -1 after Cr(VI) removal, whereas a Cr-O peak was detected at 772 cm -1 due to the association of Cr(VI) ions with ion-exchange sites. X-ray photoelectron spectroscopy analyses demonstrated that Cr(VI) was partially reduced to Cr(III) after the ion exchange on the surfaces of the fibers. Batch experiments with chromium-plating rinse water (Cr(VI) concentration = 1178.8 mg L -1 ) showed that the fibers had a Cr(VI) removal capacity of 28.1-186.4 mg g -1 under the given conditions (fiber dose = 1-10 g L -1 ). Column experiments (column length = 10 cm, inner diameter = 2.5 cm) were conducted to examine Cr(VI) removal from chromium-plating rinse water by the fibers under flow-through column conditions. The Cr(VI) removal capacities for the fibers at flow rates of 0.5 and 1.0 mL min -1 were 214.8 and 171.5 mg g -1 , respectively. This study demonstrates that KC31 fibers are effective in the removal of Cr(VI) ions from chromium-plating rinse water.

  20. Handwashing and Ebola virus disease outbreaks: A randomized comparison of soap, hand sanitizer, and 0.05% chlorine solutions on the inactivation and removal of model organisms Phi6 and E. coli from hands and persistence in rinse water.

    Science.gov (United States)

    Wolfe, Marlene K; Gallandat, Karin; Daniels, Kyle; Desmarais, Anne Marie; Scheinman, Pamela; Lantagne, Daniele

    2017-01-01

    To prevent Ebola transmission, frequent handwashing is recommended in Ebola Treatment Units and communities. However, little is known about which handwashing protocol is most efficacious. We evaluated six handwashing protocols (soap and water, alcohol-based hand sanitizer (ABHS), and 0.05% sodium dichloroisocyanurate, high-test hypochlorite, and stabilized and non-stabilized sodium hypochlorite solutions) for 1) efficacy of handwashing on the removal and inactivation of non-pathogenic model organisms and, 2) persistence of organisms in rinse water. Model organisms E. coli and bacteriophage Phi6 were used to evaluate handwashing with and without organic load added to simulate bodily fluids. Hands were inoculated with test organisms, washed, and rinsed using a glove juice method to retrieve remaining organisms. Impact was estimated by comparing the log reduction in organisms after handwashing to the log reduction without handwashing. Rinse water was collected to test for persistence of organisms. Handwashing resulted in a 1.94-3.01 log reduction in E. coli concentration without, and 2.18-3.34 with, soil load; and a 2.44-3.06 log reduction in Phi6 without, and 2.71-3.69 with, soil load. HTH performed most consistently well, with significantly greater log reductions than other handwashing protocols in three models. However, the magnitude of handwashing efficacy differences was small, suggesting protocols are similarly efficacious. Rinse water demonstrated a 0.28-4.77 log reduction in remaining E. coli without, and 0.21-4.49 with, soil load and a 1.26-2.02 log reduction in Phi6 without, and 1.30-2.20 with, soil load. Chlorine resulted in significantly less persistence of E. coli in both conditions and Phi6 without soil load in rinse water (phand hygiene in Ebola contexts, considering the potential benefit of chlorine-based methods in rinse water persistence.

  1. Optimization of the etch-and-rinse technique: New perspectives to improve resin-dentin bonding and hybrid layer integrity by reducing residual water using dimethyl sulfoxide pretreatments.

    Science.gov (United States)

    Stape, Thiago Henrique Scarabello; Tjäderhane, Leo; Abuna, Gabriel; Sinhoreti, Mário Alexandre Coelho; Martins, Luís Roberto Marcondes; Tezvergil-Mutluay, Arzu

    2018-04-13

    To determine whether bonding effectiveness and hybrid layer integrity on acid-etched dehydrated dentin would be comparable to the conventional wet-bonding technique through new dentin biomodification approaches using dimethyl sulfoxide (DMSO). Etched dentin surfaces from extracted sound molars were randomly bonded in wet or dry conditions (30s air drying) with DMSO/ethanol or DMSO/H 2 O as pretreatments using a simplified (Scotchbond Universal Adhesive, 3M ESPE: SU) and a multi-step (Adper Scotchbond Multi-Purpose, 3M ESPE: SBMP) etch-and-rinse adhesives. Untreated dentin surfaces served as control. Bonded teeth (n=8) were stored in distilled water for 24h and sectioned into resin-dentin beams (0.8mm 2 ) for microtensile bond strength test and quantitative interfacial nanoleakage analysis (n=8) under SEM. Additional teeth (n=2) were prepared for micropermeability assessment by CFLSM under simulated pulpar pressure (20cm H 2 O) using 5mM fluorescein as a tracer. Microtensile data was analyzed by 3-way ANOVA followed by Tukey Test and nanoleakage by Kruskal-Wallis and Dunn-Bonferroni multiple comparison test (α=0.05). While dry-bonding of SBMP produced significantly lower bond strengths than wet-bonding (padhesives to demineralized air-dried dentin beyond conventional wet-bonding. Less porous resin-dentin interfaces with higher bond strengths on air-dried etched dentin were achieved; nonetheless, overall efficiency varied according to DMSO's co-solvent and adhesive type. DMSO pretreatments permit etched dentin to be air-dried before hybridization facilitating residual water removal and thus improving bonding effectiveness. This challenges the current paradigm of wet-bonding requirement for the etch-and-rinse approach creating new possibilities to enhance the clinical longevity of resin-dentin interfaces. Copyright © 2018 The Academy of Dental Materials. Published by Elsevier Inc. All rights reserved.

  2. Development of the electrical discharge method for water disinfection

    International Nuclear Information System (INIS)

    Vojtenko, L.M.; Kononov, O.V.; Starchik, P.D.; Samojlenko, L.S.; Stavs'ka, S.S.

    1995-01-01

    Studies of processes of bacterially polluted water disinfection by the method of pulse electrical discharge in water are presented. The studies was performed to improve the disinfection technology. Main attention was concentrated to clear up effect of discharge instability on the disinfection. An influence of the shape and sizes of electrodes on repeatability of discharges was also investigated. It was found that salts solved in water greatly influence ultraviolet radiation absorption coefficients

  3. Handwashing and Ebola virus disease outbreaks: A randomized comparison of soap, hand sanitizer, and 0.05% chlorine solutions on the inactivation and removal of model organisms Phi6 and E. coli from hands and persistence in rinse water.

    Directory of Open Access Journals (Sweden)

    Marlene K Wolfe

    Full Text Available To prevent Ebola transmission, frequent handwashing is recommended in Ebola Treatment Units and communities. However, little is known about which handwashing protocol is most efficacious. We evaluated six handwashing protocols (soap and water, alcohol-based hand sanitizer (ABHS, and 0.05% sodium dichloroisocyanurate, high-test hypochlorite, and stabilized and non-stabilized sodium hypochlorite solutions for 1 efficacy of handwashing on the removal and inactivation of non-pathogenic model organisms and, 2 persistence of organisms in rinse water. Model organisms E. coli and bacteriophage Phi6 were used to evaluate handwashing with and without organic load added to simulate bodily fluids. Hands were inoculated with test organisms, washed, and rinsed using a glove juice method to retrieve remaining organisms. Impact was estimated by comparing the log reduction in organisms after handwashing to the log reduction without handwashing. Rinse water was collected to test for persistence of organisms. Handwashing resulted in a 1.94-3.01 log reduction in E. coli concentration without, and 2.18-3.34 with, soil load; and a 2.44-3.06 log reduction in Phi6 without, and 2.71-3.69 with, soil load. HTH performed most consistently well, with significantly greater log reductions than other handwashing protocols in three models. However, the magnitude of handwashing efficacy differences was small, suggesting protocols are similarly efficacious. Rinse water demonstrated a 0.28-4.77 log reduction in remaining E. coli without, and 0.21-4.49 with, soil load and a 1.26-2.02 log reduction in Phi6 without, and 1.30-2.20 with, soil load. Chlorine resulted in significantly less persistence of E. coli in both conditions and Phi6 without soil load in rinse water (p<0.001. Thus, chlorine-based methods may offer a benefit of reducing persistence in rinse water. We recommend responders use the most practical handwashing method to ensure hand hygiene in Ebola contexts, considering

  4. A 5 year longitudinal study of water quality for final rinsing in the single chamber washer-disinfector with a reverse osmosis plant.

    Science.gov (United States)

    Uetera, Yushi; Kishii, Kozue; Yasuhara, Hiroshi; Kumada, Naohito; Moriya, Kyoji; Saito, Ryoichi; Okazaki, Mitsuhiro; Misawa, Yoshiki; Kawamura, Kunio

    2013-01-01

    This report deals with the construction and management of the reverse osmosis (RO) water system for final rinsing of surgical instruments in the washer-disinfector. Numerous operational challenges were encountered in our RO water system and these were analyzed utilizing the Ishikawa Fishbone diagram. The aim was to find potential problems and promote preventive system management for RO water. It was found that the measures that existed were inappropriate for preventing contamination in the heat-labile RO water system. The storage tank was found to be significantly contaminated and had to be replaced with a new one equipped with a sampling port and water drainage system. Additional filters and an UV treatment lamp were installed. The whole system disinfection started 1.5 years later using a peracetic acid-based compound after confirming the material compatibility. Operator errors were found when a new water engineer took over the duty from his predecessor. It was also found that there were some deficiencies in the standard operating procedures (SOPs), and that on-the-job training was not enough. The water engineer failed to disinfect the sampling port and water drainage system. The RO membrane had been used for 4 years, even though the SOP standard specified changing it as every 3 years. Various bacteria, such as Rothia mucilaginosa, were cultured from the RO water sampled from the equipment. Because Rothia mucilaginosa is a resident in the oral cavity and upper respiratory tract, it is believed that the bacteria were introduced into the system by the maintenance personnel or working environment. Therefore, the presence of R. mucilaginosa implied the failure of sanitary maintenance procedures. This study suggests that water systems should be designed based on the plans for profound system maintenance. It also suggests that SOP and on-the job training are essential to avoid any operator errors. These results must be carefully considered when either constructing new

  5. Impacts of thermal and chemical discharges to surface water

    International Nuclear Information System (INIS)

    Stober, Q.J.

    1974-01-01

    Various aspects of thermal and chemical discharges to surface water are outlined. The major impacts of nuclear power plants on aquatic resources are disruption during construction, intake of cooling water, discharge problems, and interactions with other water users. The following topics are included under the heading, assessment of aquatic ecology: identification of flora and fauna; abundance of aquatic organisms; species-environment relationships; and identification of pre-existing environmental stress. The following topics are included under the heading, environmental effects of plant operation: entrapment of fish by cooling water; passage of plankton through cooling system; discharge area and thermal plume; chemical effluents; and plant construction. (U.S.)

  6. Pseudo-outbreak of Cupriavidus pauculus infection at an outpatient clinic related to rinsing culturette swabs in tap water.

    Science.gov (United States)

    Balada-Llasat, Joan-Miquel; Elkins, Camille; Swyers, Lettie; Bannerman, Tammy; Pancholi, Preeti

    2010-07-01

    Cupriavidus pauculus is a water microorganism rarely isolated from clinical specimens. We describe a pseudo-outbreak in which multiple strains that were associated with moistening of culturette swabs with tap water were isolated from a single clinic before collecting the patient specimen.

  7. Electrohydraulic Discharges and Nonthermal Plasma for Water Treatment

    Czech Academy of Sciences Publication Activity Database

    Locke, B.R.; Sato, M.; Hoffman, M.R.; Chang, J.S.; Šunka, Pavel

    2006-01-01

    Roč. 45, č. 1 (2006), s. 882-905 ISSN 0888-5885 Institutional research plan: CEZ:AV0Z20430508 Keywords : Electrical discharges * water cleaning * environmental applications * liquid phase reactor Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 1.518, year: 2006

  8. Properties of water surface discharge at different pulse repetition rates

    International Nuclear Information System (INIS)

    Ruma,; Yoshihara, K.; Hosseini, S. H. R.; Sakugawa, T.; Akiyama, H.; Akiyama, M.; Lukeš, P.

    2014-01-01

    The properties of water surface discharge plasma for variety of pulse repetition rates are investigated. A magnetic pulse compression (MPC) pulsed power modulator able to deliver pulse repetition rates up to 1000 Hz, with 0.5 J per pulse energy output at 25 kV, was used as the pulsed power source. Positive pulse with a point-to-plane electrode configuration was used for the experiments. The concentration and production yield of hydrogen peroxide (H 2 O 2 ) were quantitatively measured and orange II organic dye was treated, to evaluate the chemical properties of the discharge reactor. Experimental results show that the physical and chemical properties of water surface discharge are not influenced by pulse repetition rate, very different from those observed for under water discharge. The production yield of H 2 O 2 and degradation rate per pulse of the dye did not significantly vary at different pulse repetition rates under a constant discharge mode on water surface. In addition, the solution temperature, pH, and conductivity for both water surface and underwater discharge reactors were measured to compare their plasma properties for different pulse repetition rates. The results confirm that surface discharge can be employed at high pulse repetition rates as a reliable and advantageous method for industrial and environmental decontamination applications.

  9. Multi-spark discharge system for preparation of nutritious water

    Science.gov (United States)

    Nakaso, Tetsushi; Harigai, Toru; Kusumawan, Sholihatta Aziz; Shimomura, Tomoya; Tanimoto, Tsuyoshi; Suda, Yoshiyuki; Takikawa, Hirofumi

    2018-01-01

    The nitrogen compound concentration in water is increased by atmospheric-pressure plasma discharge treatment. A rod-to-water electrode discharge treatment system using plasma discharge has been developed by our group to obtain water with a high concentration of nitrogen compounds, and this plasma-treated water improves the growth of chrysanthemum roots. However, it is difficult to apply the system to the agriculture because the amount of treated water obtained by using the system too small. In this study, a multi-spark discharge system (MSDS) equipped multiple spark plugs is presented to obtain a large amount of plasma-treated water. The MSDS consisted of inexpensive parts in order to reduce the system introduction cost for agriculture. To suppress the temperature increase of the spark plugs, the 9 spark plugs were divided into 3 groups, which were discharged in order. The plasma-treated water with a NO3- concentration of 50 mg/L was prepared using the MSDS for 90 min, and the treatment efficiency was about 6 times higher than that of our previous system. It was confirmed that the NO2-, O3, and H2O2 concentrations in the water were also increased by treating the water using the MSDS.

  10. Health risk assessment for radium discharged in produced waters

    International Nuclear Information System (INIS)

    Hamilton, L.D.; Meinhold, A.F.; Nagy, J.

    1991-01-01

    Produced water generated during the production of oil and gas can contain enhanced levels of radium. This naturally occurring radioactive material (NORM) is discharged into freshwater streams, estuarine, coastal and outer continental shelf waters. Large volumes of produced waters are discharged to coastal waters along the Gulf Coast of Louisiana. The Gulf of Mexico is an important producer of fish and shellfish, and there is concern that radium discharged to coastal Louisiana could contaminate fish and shellfish used by people for food, and present a significant increase in cancer risk. This paper describes a screening-level assessment of the potential cancer risks posed by radium discharged to coastal Louisiana in oil-field produced waters. This screening analysis was performed to determine if a more comprehensive and realistic assessment is necessary, and because of the conservative assumptions embedded in the analysis overestimates the risk associated with the discharge of radium in produced waters. Two isotopes of radium (Ra-226 and Ra-228) are the radionuclides of most concern in produced water in terms of potential human health effects

  11. EPA Office of Water (OW): Facilities that Discharge to Water NHDPlus Indexed Dataset

    Data.gov (United States)

    U.S. Environmental Protection Agency — Discharge of pollutants into waters of the United States is regulated under the National Pollutant Discharge Elimination System (NPDES), a mandated provision of the...

  12. An economically viable alternative to coastal discharge of produced water

    International Nuclear Information System (INIS)

    D'Unger, C.V.; Carr, R.S.; Chapman, D.C.

    1993-01-01

    The discharge of produced waters to coastal estuaries has been common practice on the Texas coast for many years as these discharges are currently exempt from NPDES permitting. A study of the active produced water discharges in Nueces Bay, Texas revealed that all eight effluents were highly toxic as determined by the sea urchin (Arbacia punctulata) fertilization and embryological development assays. An alternative to discharging produced water into coastal estuaries is the use of disposal wells. Inactive wells can be converted to produced water disposal wells. Production records for the Nueces Bay, Texas area reveal that 52% of the gas wells produce less than 100 mcf/d and 50% of the oil wells produce less than 10 b/d. Using conservative estimates, the cost of converting an inactive well to a disposal well was calculated to be $31,500 which could be paid out by a gas well producing as little as 100 mcf/d in 26 months using only 50% of the well's profit. Combining multiple leases to a single disposal well would reduce proportionately the cost to each operation. This study has demonstrated that economically viable disposal options could be achieved in the Nueces Bay area through the imaginative and cooperative formation of produced water disposal ventures. This same model could be applied to produced water discharges in other coastal areas

  13. Toxicity evaluation of ballast water discharged at The Onne Port ...

    African Journals Online (AJOL)

    The discharge of these ballast water poses a major environmental threat to the water quality and Port infrastructures at the Onne Port complex as contaminants may find their way into the food chain/food web and bioaccumulate in the tissues of indigenous biota (microorganisms, crabs, mangrove oysters and fin-fishes).

  14. Investigation of pulsed barrier discharge in water-air gap

    International Nuclear Information System (INIS)

    Taran, V.S.; Krasnyj, V.V.; Lozina, A.S.; Shvets, O.M.

    2013-01-01

    This article presents the results of the use of a pulsed dielectric barrier discharge with water electrode and diaphragm. The spectroscopic and electrical investigations of such discharge were conducted. The ozone concentration in an aqueous solution comprised 0.7 mg/l with high-voltage pulsed power at 120 W. The discharge reviewed emission spectrum lines of molecular nitrogen and hydroxyl radicals in the range of 200...800 nm in the water-air gap. The intensity changing of luminescence lines of OH and N 2 singles depending on the applied voltage and discharge gap has been determined. Aqueous solution of indigo was used in order to determine the impact level on the organic material. Experiments on inactivation of test E. coli cultures have been carried out.

  15. Discharge Characteristics of DC Arc Water Plasma for Environmental Applications

    Science.gov (United States)

    Li, Tianming; Sooseok, Choi; Takayuki, Watanabe

    2012-12-01

    A water plasma was generated by DC arc discharge with a hafnium embedded rod-type cathode and a nozzle-type anode. The discharge characteristics were examined by changing the operation parameter of the arc current. The dynamic behavior of the arc discharge led to significant fluctuations in the arc voltage and its frequency. Analyses of the high speed image and the arc voltage waveform showed that the arc discharge was in the restrike mode and its frequency varied within several tens of kilohertz according to the operating conditions. The larger thermal plasma volume was generated by the higher flow from the forming steam with a higher restrike frequency in the higher arc current conditions. In addition, the characteristics of the water plasma jet were investigated by means of optical emission spectroscopy to identify the abundant radicals required in an efficient waste treatment process.

  16. Discharge Characteristics of DC Arc Water Plasma for Environmental Applications

    International Nuclear Information System (INIS)

    Choi, Sooseok; Watanabe, Takayuki; Li Tianming

    2012-01-01

    A water plasma was generated by DC arc discharge with a hafnium embedded rod-type cathode and a nozzle-type anode. The discharge characteristics were examined by changing the operation parameter of the arc current. The dynamic behavior of the arc discharge led to significant fluctuations in the arc voltage and its frequency. Analyses of the high speed image and the arc voltage waveform showed that the arc discharge was in the restrike mode and its frequency varied within several tens of kilohertz according to the operating conditions. The larger thermal plasma volume was generated by the higher flow from the forming steam with a higher restrike frequency in the higher arc current conditions. In addition, the characteristics of the water plasma jet were investigated by means of optical emission spectroscopy to identify the abundant radicals required in an efficient waste treatment process. (plasma technology)

  17. Processing device for discharged water from radioactive material handling facility

    International Nuclear Information System (INIS)

    Kono, Takao; Kono, Hiroyuki; Yasui, Katsuaki; Kataiki, Koichi.

    1995-01-01

    The device of the present invention comprises a mechanical floating material-removing means for removing floating materials in discharged water, an ultrafiltration device for separating processed water discharged from the removing means by membranes, a reverse osmotic filtration device for separating the permeated water and a condensing means for evaporating condensed water. Since processed water after mechanically removing floating materials is supplied to the ultrafiltration device, the load applied on the filtering membrane is reduced, to simplify the operation control as a total. In addition, since the amount of resultant condensed water is reduced, and the devolumed condensed water is condensed and dried, the condensing device is made compact and the amount of resultant wastes is reduced. (T.M.)

  18. Pulsed electrical discharge in gas bubbles in water

    Science.gov (United States)

    Gershman, Sophia

    A phenomenological picture of pulsed electrical discharge in gas bubbles in water is produced by combining electrical, spectroscopic, and imaging methods. The discharge is generated by applying one microsecond long 5 to 20 kilovolt pulses between the needle and disk electrodes submerged in water. A gas bubble is generated at the tip of the needle electrode. The study includes detailed experimental investigation of the discharge in argon bubbles and a brief look at the discharge in oxygen bubbles. Imaging, electrical characteristics, and time-resolved optical emission data point to a fast streamer propagation mechanism and formation of a plasma channel in the bubble. Spectroscopic methods based on line intensity ratios and Boltzmann plots of line intensities of argon, atomic hydrogen, and argon ions and the examination of molecular emission bands from molecular nitrogen and hydroxyl radicals provide evidence of both fast beam-like electrons and slow thermalized ones with temperatures of 0.6 -- 0.8 electron-volts. The collisional nature of plasma at atmospheric pressure affects the decay rates of optical emission. Spectroscopic study of rotational-vibrational bands of hydroxyl radical and molecular nitrogen gives vibrational and rotational excitation temperatures of the discharge of about 0.9 and 0.1 electron-volt, respectively. Imaging and electrical evidence show that discharge charge is deposited on the bubble wall and water serves as a dielectric barrier for the field strength and time scales of this experiment. Comparing the electrical and imaging information for consecutive pulses applied at a frequency of 1 Hz indicates that each discharge proceeds as an entirely new process with no memory of the previous discharge aside from long-lived chemical species, such as ozone and oxygen. Intermediate values for the discharge gap and pulse duration, low repetition rate, and unidirectional character of the applied voltage pulses make the discharge process here unique

  19. All solid state pulsed power system for water discharge

    OpenAIRE

    Sakugawa, Takashi; Yamaguchi, Takahiro; Yamamoto, Kunihiro; Kiyan, Tsuyoshi; Namihira, Takao; Katsuki, Sunao; Akiyama, Hidenori; サクガワ, タカシ; ヤマグチ, タカヒロ; ヤマモト, クニヒロ; キヤン, ツヨシ; ナミヒラ, タカオ; カツキ, スナオ; アキヤマ, ヒデノリ; 佐久川, 貴志

    2005-01-01

    Pulsed power has been used to produce non-thermal plasmas in gases that generate a high electric field at the tip of streamer discharges, where high energy electrons, free radicals, and ozone are produced. Recently, all solid state pulsed power generators, which are operated with high repetition rate, long lifetime and high reliability, have been developed for industrial applications, such as high repetition rate pulsed gas lasers, high energy density plasma (EUV sources) and water discharges...

  20. Pulse electrical discharges in water and their applications

    International Nuclear Information System (INIS)

    Sunka, Pavel

    2001-01-01

    Partial electrical discharges in a water solution as a function of conductivity have been studied experimentally. Using needle-plate electrodes it has been demonstrated that the discharge evolves in two phases. During the first streamer-like phase, the discharge propagated with a velocity of 10 6 cm/s, while during the second arc-like phase the length of the discharge remained almost constant although the current still increased. Higher solution conductivity resulted in the generation of shorter channels, in larger discharge current, and in a higher plasma electron density. Degradation of phenol by the discharge has also been demonstrated. A special metallic electrode covered by a thin layer of porous ceramic has been developed and used for generation of a multichannel discharge. At comparable solution conductivity the ceramic-coated electrode produced plasma with very similar parameters as the needle-plate electrode configuration. Generation of strong focused shock waves by the multichannel discharge in a highly conductive solution has also been demonstrated

  1. Fluoride Rinses, Gels and Foams

    DEFF Research Database (Denmark)

    Twetman, Svante; Keller, Mette K

    2016-01-01

    AIM: The aim of this conference paper was to systematically review the quality of evidence and summarize the findings of clinical trials published after 2002 using fluoride mouth rinses, fluoride gels or foams for the prevention of dental caries. METHODS: Relevant papers were selected after...... (6 on fluoride mouth rinse, 10 on fluoride gel and 3 on fluoride foam); 6 had a low risk of bias while 2 had a moderate risk. All fluoride measures appeared to be beneficial in preventing crown caries and reversing root caries, but the quality of evidence was graded as low for fluoride mouth rinse......, moderate for fluoride gel and very low for acidulated fluoride foam. No conclusions could be drawn on the cost-effectiveness. CONCLUSIONS: This review, covering the recent decade, has further substantiated the evidence for a caries-preventive effect of fluoride mouth rinse, fluoride gel and foam...

  2. Water cleaning by pulsed corona discharges

    NARCIS (Netherlands)

    Grabowski, L.R.; Veldhuizen, van E.M.; Rutgers, W.R.

    2004-01-01

    Direct electrical energization methods for water cleaning are under investigation in the framework of the ytriD-project1. The emphasis of the first stage of the project is optimization of the reactor configuration regarding the energy efficiency. A comparison is made between a batch reactor and an

  3. Measurements of total suspended matter - How does salinity and the amount of rinse water influence the results; Maetning av totalt suspenderat material - Hur paaverkar salthalt och maengden skoeljvatten resultatet

    Energy Technology Data Exchange (ETDEWEB)

    Hall, Bjoern (Bjoern Hall, Miljoe och Foerbraenningskemi, Onsala (Sweden))

    2010-03-15

    Under regulations for incineration of waste NFS 2002:28 total suspended matter (tsm) in wastewater from incineration plants are analyzed by daily sampling measurement or by representative flow-proportional 24-hour test. It has been shown that many plants that analyzes the suspended matter according to EN 872:2005 are having trouble keeping their conditions for suspended solids constant. This applies mainly to plants rated for a high chloride content in the closing process. Waste Sweden has for years drawn attention to this problem and have with a joint working group with representatives from the Swedish waste incineration plants tried to obtain a better understanding of this phenomenon. The basic question is whether the water from the facilities in question really contain high levels of tsm or if there is something else behind the observed concentrations. The results from this study suggest that the most important factor is the salinity and the amount of rinse water used in the analysis. Under the standard, all samples are washed with 2 x 20 ml of water. If salinity exceeds 1000 mg/l, a further 3 x 50 ml used. How this process is this implemented in practice varies from laboratory to laboratory and there is no laboratory that regularly measure the salinity of the sample. It is not specified especially when submitting the sample uses most of the labs normal rinse water of 2 x 20 ml. The findings also indicate that the samples with very high salinities the standard stipulated 190 mls is not enough. This would likely lead to that further rinse water is needed. In order to establish safe Several measurements would be needed to confirm this assumption. A relatively simple way to obtain an idea of the salinity of the test is to measure its conductivity. Accordingly, this could be a first step on to get a more consistent performance than is the case at present

  4. Environmental contaminants in oil field produced waters discharged into wetlands

    International Nuclear Information System (INIS)

    Ramirez, P. Jr.

    1994-01-01

    The 866-acre Loch Katrine wetland complex in Park County, Wyoming provides habitat for many species of aquatic birds. The complex is sustained primarily by oil field produced waters. This study was designed to determine if constituents in oil field produced waters discharged into Custer Lake and to Loch Katrine pose a risk to aquatic birds inhabiting the wetlands. Trace elements, hydrocarbons and radium-226 concentrations were analyzed in water, sediment and biota collected from the complex during 1992. Arsenic, boron, radium-226 and zinc were elevated in some matrices. The presence of radium-226 in aquatic vegetation suggests that this radionuclide is available to aquatic birds. Oil and grease concentrations in water from the produced water discharge exceeded the maximum 10 mg/l permitted by the WDEQ (1990). Total aliphatic and aromatic hydrocarbon concentrations in sediments were highest at the produced water discharge, 6.376 μg/g, followed by Custer Lake, 1.104 μg/g. The higher levels of hydrocarbons found at Custer Lake, compared to Loch Katrine, may be explained by Custer Lake's closer proximity to the discharge. Benzo(a)pyrene was not detected in bile from gadwalls collected at Loch Katrine but was detected in bile from northern shovelers collected at Custer Lake. Benzo(a)pyrene concentrations in northern shoveler bile ranged from 500 to 960 ng/g (ppb) wet weight. The presence of benzo(a)pyrene in the shovelers indicates exposure to petroleum hydrocarbons

  5. Decolorization and degradation of reactive dye during the dyed cotton fabric rinsing process.

    Science.gov (United States)

    Luo, Deng-Hong; Zheng, Qing-Kang; Chen, Sheng; Liu, Qing-Shu; Wang, Xiu-Xing; Guan, Yu; Pu, Zong-Yao

    2010-01-01

    Dyeing process of textile consumes large quantities of water, which results in huge amounts of colored wastewater. Most of the dye wastewater treating methods focused on the treatment of wastewater after the rinsing process of dyed textile. In this paper, tetraacetylethylenediamine/hydrogen peroxide (TAED/H₂O₂) active oxidation (AO) system was developed to rinse dyed textile and decolorize the rinsing wastewater simultaneously. The results indicated that the decolorization ratio of the rinse effluent obtained by AO method were in the range of 51.72%-84.15% according to different dyes and the COD value decreased more than 30% compared with that of traditional rinsing process. The decolorization kinetics investigation showed that the decolorization of dyes during AO rinsing process followed the law of pseudo-first order kinetics. The result of UV-Vis and UPLC-MS analysis demonstrated that the dye was degraded into colorless organic molecular fragments and partly mineralized during the AO rinsing process.

  6. Preparation of gold nanoparticles by arc discharge in water

    International Nuclear Information System (INIS)

    Lung, Jen-Kuang; Huang, Jen-Chuen; Tien, Der-Chi; Liao, Chih-Yu; Tseng, Kuo-Hsiung; Tsung, Tsing-Tshin; Kao, Wen-Shiow; Tsai, Teh-Hua; Jwo, Ching-Song; Lin, Hong-Ming; Stobinski, Leszek

    2007-01-01

    Gold nanoparticles have been attracting attention due to their extensive application in chemistry, physics, material science, electronics, catalysis and bionanotechnology. Synthesis of gold nanoparticles often involves toxic and expensive physical-chemistry methods. Preparation of gold nanoparticles by arc discharge in water is proposed for the first time. Fabrication of gold nanostructures in deionized water has been successfully established. The evidence of gold particles' light absorbance reveals a unique surface plasmon resonance for Au nanoparticles suspended in deionized water. Gold nanostructures uniformly dispersed in water, their UV-Vis absorption and crystalline size are shown. Our experimental results demonstrate that fabrication of gold nanoparticles by arc discharge in water is an alternative, cheap, effective and environmentally friendly method

  7. Some aspects of cooling water discharges and environmental enhancement

    International Nuclear Information System (INIS)

    Grimaas, U.

    1976-01-01

    As a consequence of the effects of cooling water discharge on the environment, the siting of nuclear power plants is approached with cautiousness. The pros and cons are discussed of siting near bodies of good quality water or in more densely populated or industrial areas. Properties and effects of thermal discharges are elaborated. The effects of heat on the activity of individual organisms, on the accumulation of organic material, on the mineralization rate of organic matter and on the transport of oxygen all have influences on recipient water bodies. Examples of siting Swedish thermal power stations are described and these indicate some negative effects. However, the results do not repudiate the possibility of good effects from the design of new cooling water intake and discharge systems that would speed up the mineralization of organic matters by addition of heat and oxygen. It is concluded that, when choosing between possible sites, areas should be selected where the available energy of the discharge can be used to improve water quality. (author)

  8. General review of literature relevant to coastal water discharges

    International Nuclear Information System (INIS)

    Pentreath, R.J.

    1985-01-01

    This review on the behaviour of radionuclides released into coastal water from the radioactive discharges, prepared on the basis of existing publications and documents, is divided into parts on pathways of exposure, behaviour of radionuclides in coastal environments, biological avialability of radionuclides, habit surveys and critical groups, assessment of dose to man and the effects of radiation on aquatic organisms

  9. Determination of radionuclides in discharged water from gold ...

    African Journals Online (AJOL)

    The levels of radionuclides concentrations in discharged water from gold processing into the environment of Bogoso (Ghana) were determined using radioanalytical techniques. Radioactivity screening was first carried out to identify physical and chemical processing stages that might be concentrating the radionuclides.

  10. Water reuse achieved by zero discharge of aqueous waste

    International Nuclear Information System (INIS)

    Kelchner, B.L.

    1976-01-01

    Plans for zero discharge of aqueous waste from ERDA's nuclear weapons plant near Denver are discussed. Two plants - a process waste treatment facility now under construction, and a reverse osmosis desalting plant now under design, will provide total reuse of waste water for boiler feed and cooling tower supply. Seventy million gallons of water per year will be conserved and downstream municipalities will be free of inadvertent pollution hazards

  11. Electron beam sterilization of water discharged from sewage

    International Nuclear Information System (INIS)

    Miyata, Teijiro; Arai, Hidehiko; Tokunaga, Okihiro; Machi, Sueo; Kondo, Masaki; Minemura, Takashi; Nakao, Akio; Seike, Yasuhiko.

    1989-01-01

    At present, the water treated at city sewerages is discharged to rivers after the chlorine sterilization, but it was clarified recently that this chlorine treatment produces carcinogenic organic chlorine compounds, and residual chlorine exerts harmful effect to aquatics, therefore, it is desirable to develop the sterilization techniques substituting for chlorine treatment. Already many reports elucidated that irradiation is effective for the sterilization of the water discharged from sewerage. However, as the technical subject for putting radiation process in practical use, the treatment of large quantity was a problem. Recently by the progress of the technology of manufacturing electron accelerators, the equipment with large power output which can treat in large quantity was developed, and it has become applicable also to sewage treatment. Therefore, the authors examined the practicality of electron beam process as the substitute technology for chlorine sterilizaiton. In the case of using electron beam, though the power output of accelerators is large, the flight range of electron beam in water is short. The comparison of the sterilization effect of electron beam with that of Co-60 gamma ray, the effects of water depth, discharged water quality and water velocity on the sterilization effect and so on were experimentally examined. (K.I.)

  12. EPA Enforcement and Compliance History Online: Water Discharge Monitoring Report Data Sets for FY2010

    Data.gov (United States)

    U.S. Environmental Protection Agency — Integrated Compliance Information System (ICIS) National Pollutant Discharge Elimination System (NPDES) Discharge Monitoring Report (DMR) data sets for Clean Water...

  13. EPA Enforcement and Compliance History Online: Water Discharge Monitoring Report Data Sets for FY2015

    Data.gov (United States)

    U.S. Environmental Protection Agency — Integrated Compliance Information System (ICIS) National Pollutant Discharge Elimination System (NPDES) Discharge Monitoring Report (DMR) data sets for Clean Water...

  14. EPA Enforcement and Compliance History Online: Water Discharge Monitoring Report Data Sets for FY2014

    Data.gov (United States)

    U.S. Environmental Protection Agency — Integrated Compliance Information System (ICIS) National Pollutant Discharge Elimination System (NPDES) Discharge Monitoring Report (DMR) data sets for Clean Water...

  15. EPA Enforcement and Compliance History Online: Water Discharge Monitoring Report Data Sets for FY2009

    Data.gov (United States)

    U.S. Environmental Protection Agency — Integrated Compliance Information System (ICIS) National Pollutant Discharge Elimination System (NPDES) Discharge Monitoring Report (DMR) data sets for Clean Water...

  16. EPA Enforcement and Compliance History Online: Water Discharge Monitoring Report Data Sets for FY2016

    Data.gov (United States)

    U.S. Environmental Protection Agency — Integrated Compliance Information System (ICIS) National Pollutant Discharge Elimination System (NPDES) Discharge Monitoring Report (DMR) data sets for Clean Water...

  17. EPA Enforcement and Compliance History Online: Water Discharge Monitoring Report Data Sets for FY2013

    Data.gov (United States)

    U.S. Environmental Protection Agency — Integrated Compliance Information System (ICIS) National Pollutant Discharge Elimination System (NPDES) Discharge Monitoring Report (DMR) data sets for Clean Water...

  18. Shock waves in water at low energy pulsed electric discharges

    International Nuclear Information System (INIS)

    Pinchuk, M E; Kolikov, V A; Rutberg, Ph G; Leks, A G; Dolinovskaya, R V; Snetov, V N; Stogov, A Yu

    2012-01-01

    Experimental results of shock wave formation and propagation in water at low energy pulsed electric discharges are presented. To study the hydrodynamic structure of the shock waves, the direct shadow optical diagnostic device with time resolution of 5 ns and spatial resolution of 0.1 mm was designed and developed. Synchronization of the diagnostic and electrodischarge units by the fast optocouplers was carried out. The dependences of shock wave velocities after breakdown of interelectrode gap for various energy inputs (at range of ≤1 J) into discharge were obtained. Based on the experimental results the recommendations for the adjustment parameters of the power supply and load were suggested.

  19. Properties of water surface discharge at different pulse repetition rates

    Czech Academy of Sciences Publication Activity Database

    Ruma, R.; Hosseini, S.H.R.; Yoshihara, K.; Akiyama, M.; Sakugawa, T.; Lukeš, Petr; Akiyama, H.

    2014-01-01

    Roč. 116, č. 12 (2014), s. 123304-123304 ISSN 0021-8979 Grant - others:Rada Programu interní podpory projektů mezinárodní spolupráce AV ČR(CZ) M100431203 Program:M Institutional support: RVO:61389021 Keywords : plasma in air * water surface discharge * pulse frequency * hydrogen peroxide * organic dye Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 2.183, year: 2014 http://dx.doi.org/ 10.1063/1.4896266

  20. Characteristics of pulse corona discharge over water surface

    Science.gov (United States)

    Fujii, Tomio; Arao, Yasushi; Rea, Massimo

    2008-12-01

    Production of ozone and OH radical is required to advance the plasma chemical reactions in the NOx removal processes for combustion gas treatment. The corona discharge to the water surface is expected to induce the good conditions for the proceeding of the NO oxidation and the NO2 dissolution removal into water. In order to get the fundamental data of the corona discharge over the water surface, the positive and negative V-I characteristics and the ozone production were measured with the multi needle and the saw-edge type of the discharge electrodes. The pulse corona characteristics were also measured with some different waveforms of the applied pulse voltage. The experiments were carried out under the atmospheric pressure and room temperature. Both the DC and the pulse corona to the water surface showed a stable and almost the same V-I characteristics as to plate electrodes though the surface of water was waved by corona wind. The positive streamer corona showed more ozone production than the negative one both in the DC and in the pulse corona.

  1. Characteristics of pulse corona discharge over water surface

    International Nuclear Information System (INIS)

    Fujii, Tomio; Arao, Yasushi; Rea, Massimo

    2008-01-01

    Production of ozone and OH radical is required to advance the plasma chemical reactions in the NOx removal processes for combustion gas treatment. The corona discharge to the water surface is expected to induce the good conditions for the proceeding of the NO oxidation and the NO 2 dissolution removal into water. In order to get the fundamental data of the corona discharge over the water surface, the positive and negative V-I characteristics and the ozone production were measured with the multi needle and the saw-edge type of the discharge electrodes. The pulse corona characteristics were also measured with some different waveforms of the applied pulse voltage. The experiments were carried out under the atmospheric pressure and room temperature. Both the DC and the pulse corona to the water surface showed a stable and almost the same V-I characteristics as to plate electrodes though the surface of water was waved by corona wind. The positive streamer corona showed more ozone production than the negative one both in the DC and in the pulse corona.

  2. A study into the treatability of ochreous mine water discharges

    Energy Technology Data Exchange (ETDEWEB)

    Clark, C J; Crawshaw, D H

    1979-01-01

    The oxidation of ferrous salts in solution from waste-water discharges from 3 abandoned and flooded mines near Bromley, Lancs, (UK) has since 1968 caused discoloration in the Calder River. Deposition and dilution decreases the ochreous effect, but the iron oxide is harmful to the benthos by producing a low dissolved-oxygen environment. The Calder River is only a Class 4 river below the confluence with the stream which carried the mine waters, and pilot-plant studies and field trials are described to determine the feasibility of full- scale treatment of the stream waters, resulting in the recommendation of lagoon treatment followed by neutralization.

  3. Discharge and Treatment of Waste Water in Denmark

    DEFF Research Database (Denmark)

    Larsen, Torben

    1990-01-01

    This paper describes the waste water treatment situation in the area of Esbjerg. This example was chosen because the situation in Esbjerg is typical of that of most towns in Denmark, and because Esbjerg is closest to the British situation with respect to the receiving water. Esbjerg has...... a population of 70.000 inhabitans, and waste water treatment takes place in two treatment plants. These plants are now being extended to perform tertiary treatment, to fulfil the new Danish requirements. From 1992, the maximum average concentrations allowed for municipal waste water discharges to receiving...... waters will be; 15 mg/1 for BOD5, 8 mg/1 for total nitrogen, and 1.5 mg/1 for total phosphorus. These general requirements cover all types of receiving waters, but regional authorities have, in a number of cases, fixed lower values for sensitive areas....

  4. Benefits of Riverine Water Discharge into the Lorian Swamp, Kenya

    Directory of Open Access Journals (Sweden)

    Zipporah Musyimi

    2012-12-01

    Full Text Available Use and retention of river water in African highlands deprive communities in arid lowlands of their benefits. This paper reviews information on water use in the Ewaso Ng’iro catchment, Kenya, to evaluate the effects of upstream abstraction on the Lorian Swamp, a wetland used by pastoralists downstream. We first assess the abstractions and demands for water upstream and the river water supplies at the upper and the lower end of the Lorian Swamp. Further analysis of 12 years of monthly SPOT-VEGETATION satellite imagery reveals higher NDVI (Normalized Differential Vegetation Index values in the swamp than nearby rainfed areas, with the difference in NDVI between the two positively related to river water discharged into the swamp. The paper next reviews the benefits derived from water entering the swamp and the vulnerability to abstractions for three categories of water: (i the surface water used for drinking and sanitation; (ii the surface water that supports forage production; and (iii the water that recharges the Merti Aquifer. Our results suggest that benefits from surface water for domestic use and forage production are vulnerable to abstractions upstream whereas the benefits from the aquifer, with significant fossil water, are likely to be affected in the long run, but not the short term.

  5. Organohalogens in chlorinated cooling waters discharged from nuclear power stations

    International Nuclear Information System (INIS)

    Bean, R.M.; Mann, D.C.; Neitzel, D.A.

    1983-01-01

    For the power plant discharges studied to date, measured concentrations of trihalomethanes are lower than might be expected, particularly in cooling tower water, which can lose THMs to the atmosphere. In the cooling towers, where chlorine was added in higher concentrations and for longer residence times, halogenated phenols can contribute significantly to the total organic halogen content of the discharge. The way in which cooling towers are operated may also influence the production of halogenated phenols because they concentrate the incoming water by a factor of 4 or 5. In addition, the phenols, which act as a substrate for the halogenating agent, are also probably concentrated by the cooling tower operation and may be prevented from being biodegraded by addition of the same biocide that produces the halogenated phenols. 8 references, 4 tables

  6. Determination of radionuclides in discharged water from gold ...

    African Journals Online (AJOL)

    Long-lived radionuclides from the Uranium-, Thorium- and Actinium-decay chains in the discharged water into the environment were radiochemically separated and the activity concentrations determined for 238U-series ranged from 3.8 ± 1.5 to 178 ± 19 mBqL-1, 232Th-series ranged from < 2.0 to 47.8 ± 7.3 mBqL-1 and ...

  7. Initial studies of submarine groundwater discharge in Mississippi coastal waters

    Science.gov (United States)

    Shiller, A. M.; Moore, W. S.; Joung, D. J.; Box, H.; Ho, P.; Whitmore, L. M.; Gilbert, M.; Anderson, H.

    2017-12-01

    Submarine groundwater discharge (SGD) is a critical component of coastal ecosystems, affecting biogeochemistry and productivity. The SGD flux and effect on the ecosystem of the Mississippi (MS) Bight has not previously been studied. We have determined Ba, δ18O of water, and Ra-isotopes, together with nutrients, chlorophyll, and dissolved oxygen (DO) during multiple cruises from fall 2015 to summer 2016. Water isotope distributions (δ18O) show that, although the MS River Delta bounds the western side of the Bight, nonetheless, Mobile Bay and other local rivers are the Bight's dominant freshwater sources. But elevated dissolved Ba and Ra isotopes cannot be explained by river input. Spatially, SGD in the MS Bight occurs over a wide area, with hot spots near the barrier islands (e.g., Chandeleurs, Horn and Dauphin Islands) and the mouth of Mobile Bay, probably in association with old buried river channels, or dredged ship channels. Based on their high concentrations in saline groundwaters sampled on the barrier islands, the elevated Ba and Ra in MS Bight water are likely due to SGD. In subsurface waters, long-lived Ra isotopes were negatively correlated with DO during spring and summer 2016, suggesting direct discharge of DO-depleted groundwater and/or accumulation of SGD-derived Ra and microbial DO consumption under strongly stratified conditions. Our ongoing study suggests that seasonal variability in flushing, water stratification, and SGD input play important roles in biological production and bottom water hypoxia in the MS Bight.

  8. Risk assessment for produced water discharges to Louisiana Open Bays

    Energy Technology Data Exchange (ETDEWEB)

    Meinhold, A.F.; DePhillips, M.P.; Holtzman, S.

    1995-06-23

    Data were collected prior to termination of discharge at three sites (including two open bay sites at Delacroix Island and Bay De Chene) for the risk assessments. The Delacroix Island Oil and Gas Field has been in production since the first well drilling in 1940; the Bay De Chene Field, since 1942. Concentrations of 226Ra, 228Ra, 210Po, and 228Th were measured in discharges. Radium conc. were measured in fish and shellfish tissues. Sediment PAH and metal conc. were also available. Benthos sampling was conducted. A survey of fishermen was conducted. The tiered risk assessment showed that human health risks from radium in produced water appear to be small; ecological risk from radium and other radionuclides in produced water also appear small. Many of the chemical contaminants discharged to open Louisiana bays appear to present little human health or ecological risk. A conservative screening analysis suggested potential risks to human health from Hg and Pb and a potential risk to ecological receptors from total effluent, Sb, Cd, Cu, Pb, Ni, Ag, Zn, and phenol in the water column and PAHs in sediment; quantitiative risk assessments are being done for these contaminants.

  9. Rinse, Reuse and Scream

    Science.gov (United States)

    Sutley, Jane

    2009-01-01

    The author of this article describes how her eighth grade art students heighten their awareness of differences between their public self and their inner self by: manipulating water bottles to create sculptural self-portraits; constructing armatures of the generic person in "The Scream" by Edward Munch; finding and collecting examples of images and…

  10. Modification of surface properties of LLDPE by water plasma discharge

    International Nuclear Information System (INIS)

    Chantara Thevy Ratnam; Hill, D.J.T.; Firas Rasoul; Whittaker, A.K.; Imelda Keen

    2007-01-01

    Linear low density polyethylene (LLDPE) surface was modified by water plasma treatment. The LLDPE surface was treated at 10 and 20 W discharge power at various exposure times. A laboratory scale Megatherm radio frequency (RF) plasma apparatus that operates at 27 MHz was used to generate the water plasmas. The changes in chemical structure of the LLDPE polymeric chain upon plasma treatment were characterized by FTIR and XPS techniques. The selectivity of trifluoroacetic anhydride (TFAA) toward hydroxyl groups is used to quantify the hydroxyl groups formed on the polymer surface upon plasma treatment. After exposition to the plasma discharge a decline in water contact angle were observed. FTIR and XPS measurements indicate an oxidation of degraded polymeric chains and creation of hydroxyl, carbonyl, ether, ester and carboxyl groups. Chemical derivatization with TFAA of water plasma treated polymer surfaces has shown that under the conditions employed, a very small (less than 5%) of the oxygen introduced by the water plasma treatment was present as hydroxyl group. (Author)

  11. Pressure wave propagation in the discharge piping with water pool

    International Nuclear Information System (INIS)

    Bang, Young S.; Seul, Kwang W.; Kim, In Goo

    2004-01-01

    Pressure wave propagation in the discharge piping with a sparger submerged in a water pool, following the opening of a safety relief valve, is analyzed. To predict the pressure transient behavior, a RELAP5/MOD3 code is used. The applicability of the RELAP5 code and the adequacy of the present modeling scheme are confirmed by simulating the applicable experiment on a water hammer with voiding. As a base case, the modeling scheme was used to calculate the wave propagation inside a vertical pipe with sparger holes and submerged within a water pool. In addition, the effects on wave propagation of geometric factors, such as the loss coefficient, the pipe configuration, and the subdivision of sparger pipe, are investigated. The effects of inflow conditions, such as water slug inflow and the slow opening of a safety relief valve are also examined

  12. GRACE-based estimates of water discharge over the Yellow River basin

    Directory of Open Access Journals (Sweden)

    Qiong Li

    2016-05-01

    Full Text Available As critical component of hydrologic cycle, basin discharge is a key issue for understanding the hydrological and climatologic related to water and energy cycles. Combining GRACE gravity field models with ET from GLDAS models and precipitation from GPCP, discharge of the Yellow River basin are estimated from the water balance equation. While comparing the results with discharge from GLDAS model and in situ measurements, the results reveal that discharge from Mosaic and CLM GLDAS model can partially represent the river discharge and the discharge estimation from water balance equation could reflect the discharge from precipitation over the Yellow River basin.

  13. Waste water discharge and its effect on the quality of water of Mahim creek and bay

    Digital Repository Service at National Institute of Oceanography (India)

    Zingde, M.D.; Desai, B.N.

    Coastal environment around Mahim was monitored to evaluate the effects of domestic and industrial waste water discharge in Mahim Creek, Maharashtra, India. Vertical salinity and DO gradient occasionally observed in the Mahim Bay during postmonsoon...

  14. Grafted cellulose for PAHs removal present in industrial discharge waters

    Science.gov (United States)

    Euvrard, Elise; Druart, Coline; Poupeney, Amandine; Crini, Nadia; Vismara, Elena; Lanza, Tommaso; Torri, Giangiacomo; Gavoille, Sophie; Crini, Gregorio

    2014-05-01

    Keywords: cellulose; biosorbent; PAHs; polycontaminated wastewaters; trace levels. Polycyclic aromatic hydrocarbons (PAHs), chemicals essentially formed during incomplete combustion of organic materials from anthropogenic activities, were present in all compartments of the ecosystem, air, water and soil. Notably, a part of PAHs found in aquatic system was introduced through industrial discharge waters. Since the Water Framework Directive has classified certain PAHs as priority hazardous substances, industrials are called to take account this kind of organic pollutants in their global environmental concern. Conventional materials such as activated carbons definitively proved their worth as finishing treatment systems but remained costly. In this study, we proposed to use cellulose grafted with glycidyl methacrylate [1] for the removal of PAHs present in discharge waters of surface treatment industries. Firstly, to develop the device, we worked with synthetic solutions containing 16 PAHs at 500 ng/L. Two types of grafted cellulose were tested over a closed-loop column with a concentration of 4g cellulose/L: cellulose C2 with a hydroxide group and cellulose C4 with an amine group. No PAH was retained by the raw cellulose whereas abatement percentages of PAHs were similar between C2 and C4 (94% and 98%, respectively, for the sum of the 16 PAHs) with an experiment duration of 400 min (corresponding to about 20 cycles through grafted cellulose). Secondly, to determine the shorter time to abate the amount maximum of PAHs through the system, a kinetic was realized from 20 min (one cycle) to 400 min with C4. The steady state (corresponding to about 95% of abatement of the total PAHs) was reached at 160 min. Finally, the system was then tested with real industrial discharge waters containing both mineral and organic compounds. The results indicated that the abatement percentage of PAHs was similar between C2 and C4, corroborating the tests with synthetic solution. In return

  15. Water Treatment Using Plasma Discharge with Variation of Electrode Materials

    Science.gov (United States)

    Chanan, N.; Kusumandari; Saraswati, T. E.

    2018-03-01

    This research studied water treatment using plasma discharge. Plasma generated in this study produced active species that played a role in organic compound decomposition. The plasma reactor consisted of two needle electrodes made from stainless steel, tungsten, aluminium and grafit. It placed approximately 2 mm above the solution and connected with high-AC voltage. A solution of methylene blue used as an organic solution model. Plasma treatment times were 2, 4, 6, 8 and 10 min. The absorbance, temperature and pH of the solution were measured before and after treatment using various electrodes. The best electrode used in plasma discharging for methylene blue absorbance reduction was the graphite electrode, which provided the highest degradation efficiency of 98% at 6 min of treatment time.

  16. Generation of ozone by pulsed corona discharge over water surface in hybrid gas-liquid electrical discharge reactor

    Czech Academy of Sciences Publication Activity Database

    Lukeš, Petr; Člupek, Martin; Babický, Václav; Šunka, Pavel; Janda, V.

    2005-01-01

    Roč. 38, č. 3 (2005), s. 409-416 ISSN 0022-3727 R&D Projects: GA ČR(CZ) GA202/02/1026 Institutional research plan: CEZ:AV0Z20430508 Keywords : Corona discharge * hybrid reactor * ozone * water treatment Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 1.957, year: 2005

  17. Monitoring Environmental Recovery at Terminated Produced Water Discharge Sites in Coastal Louisiana Waters

    Energy Technology Data Exchange (ETDEWEB)

    Continental Shelf Associates, Inc.

    1999-08-16

    This report presents the results of a study of terminated produced water discharge sites in the coastal waters of Louisiana. Environmental recovery at the sites is documented by comparing pre-termination and post-termination (six months and one year) data. Produced water, sediments, and sediment interstitial water samples were analyzed for radionuclides, metals, and hydrocarbons. Benthic infauna were identified from samples collected in the vicinity of the discharge and reference sites. Radium isotope activities were determined in fish and crustacean samples. In addition, an environmental risk assessment is made on the basis of the concentrations of metals and hydrocarbons determined in the samples.

  18. Processing method for discharged radioactive laundry water waste

    International Nuclear Information System (INIS)

    Izumida, Tatsuo; Kitsukawa, Ryozo; Tsuchiya, Hiroyuki; Kiuchi, Yoshimasa; Hattori, Yasuo.

    1995-01-01

    In order to process discharged radioactive laundry water wastes safely and decrease radioactive wastes, bubbling of a surface active agent in a detergent which causes a problem upon its condensation is suppressed, so that the liquid condensate are continuously and easily dried into a powder. A nonionic surface active agent is used against the bubbling of the surface active agent. In addition, the bubbling in an the evaporation can is reduced, and the powderization is facilitated by adding an appropriate inorganic builder. (T.M.)

  19. Ignition modes of nanosecond discharge with bubbles in distilled water

    International Nuclear Information System (INIS)

    Hamdan, Ahmad; Cha, Min Suk

    2015-01-01

    Here, we present the microscopic physical characteristics of nanosecond discharges with an array of bubbles in distilled water. In particular, applying a single high-voltage pulse, four delayed intensified charge-coupled device cameras successfully visualized four successive images during a single discharge event. We identified three distinctive modes of ignition inside a bubble, depending on the relative location of the bubble with respect to pin-to-hollow needle electrodes when a single bubble was located in an inter-electrode gap of 1 mm: anode-driven ignition, cathode-driven ignition, and co-ignition near both electrodes. Anode- and cathode-driven ignitions evolved into either a complete propagation of the streamer or an incomplete propagation, which were limited in location by proximity to an ignition location, while co-ignitions consistently showed complete propagation. When we increased the gap to 2 mm to accommodate multiple bubbles in the gap, an ignited bubble near the cathode was able to cause the ignition of an upper adjacent bubble. Bubble–bubble interface zones can also be spots of ignition, such that we observed simultaneous co-ignitions in the zones of bubble–bubble interfaces and near electrodes with triple bubbles. We compared the experimental results of discharge propagation with different ignition modes between Ar, He, and N 2 bubbles. In addition, numerical simulations for static electric fields reasonably supported observed ignition behavior such that field intensity was locally enhanced. (paper)

  20. Rinsing with antacid suspension reduces hydrochloric acid-induced erosion.

    Science.gov (United States)

    Alves, Maria do Socorro Coelho; Mantilla, Taís Fonseca; Bridi, Enrico Coser; Basting, Roberta Tarkany; França, Fabiana Mantovani Gomes; Amaral, Flávia Lucisano Botelho; Turssi, Cecilia Pedroso

    2016-01-01

    Mouthrinsing with antacids, following erosive episodes, have been suggested as a preventative strategy to minimize tooth surface loss due to their neutralizing effect. The purpose of this in situ study was to evaluate the effect of an antacid suspension containing sodium alginate, sodium bicarbonate and calcium carbonate in controlling simulated erosion of enamel of intrinsic origin. The experimental units were 48 slabs (3×3×2mm) of bovine enamel, randomly divided among 12 volunteers who wore palatal appliances with two enamel slabs. One of them was exposed extra-orally twice a day to 25mL of a hydrochloric acid (HCl) solution (0.01M, pH 2) for 2min. There were two independent phases, lasting 5 days each. In the first phase, according to a random scheme, half of the participants rinsed with 10mL of antacid suspension (Gaviscon(®), Reckitt Benckiser Healthcare Ltd.), while the remainder was rinsed with deionized water, for 1min. For the second phase, new slabs were inserted and participants switched to the treatment not received in the first stage. Therefore, the groups were as follows: (a) erosive challenge with HCl+antacid suspension; (b) erosive challenge with HCl+deionized water (DIW); (c) no erosive challenge+antacid suspension; (d) no erosive challenge+DIW. Specimens were assessed in terms of surface loss using optical profilometry and Knoop microhardness. The data were analyzed using repeated measures two-way analysis of variance and Tukey's tests. Compared to DIW rinses, surface loss of enamel was significantly lower when using an antacid rinse following erosive challenges (p=0.015). The Knoop microhardness of the enamel was significantly higher when the antacid rinse was used (p=0.026). The antacid suspension containing sodium alginate, sodium bicarbonate and calcium carbonate, rinsed after erosive challenges of intrinsic origin, reduced enamel surface loss. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. 77 FR 33969 - Standards for Living Organisms in Ships' Ballast Water Discharged in U.S. Waters

    Science.gov (United States)

    2012-06-08

    ...-10486] RIN 1625-AA32 Standards for Living Organisms in Ships' Ballast Water Discharged in U.S. Waters... Living Organisms in Ships' Ballast Water Discharged in U.S. Waters.'' Six technical errors were.... Waters.'' Six technical errors were inadvertently published in the final rule that require correction...

  2. Recycled Coarse Aggregate Produced by Pulsed Discharge in Water

    Science.gov (United States)

    Namihira, Takao; Shigeishi, Mitsuhiro; Nakashima, Kazuyuki; Murakami, Akira; Kuroki, Kaori; Kiyan, Tsuyoshi; Tomoda, Yuichi; Sakugawa, Takashi; Katsuki, Sunao; Akiyama, Hidenori; Ohtsu, Masayasu

    In Japan, the recycling ratio of concrete scraps has been kept over 98 % after the Law for the Recycling of Construction Materials was enforced in 2000. In the present, most of concrete scraps were recycled as the Lower Subbase Course Material. On the other hand, it is predicted to be difficult to keep this higher recycling ratio in the near future because concrete scraps increase rapidly and would reach to over 3 times of present situation in 2010. In addition, the demand of concrete scraps as the Lower Subbase Course Material has been decreased. Therefore, new way to reuse concrete scraps must be developed. Concrete scraps normally consist of 70 % of coarse aggregate, 19 % of water and 11 % of cement. To obtain the higher recycling ratio, the higher recycling ratio of coarse aggregate is desired. In this paper, a new method for recycling coarse aggregate from concrete scraps has been developed and demonstrated. The system includes a Marx generator and a point to hemisphere mesh electrode immersed in water. In the demonstration, the test piece of concrete scrap was located between the electrodes and was treated by the pulsed discharge. After discharge treatment of test piece, the recycling coarse aggregates were evaluated under JIS and TS and had enough quality for utilization as the coarse aggregate.

  3. Pulsed dielectric barrier discharge for Bacillus subtilis inactivation in water

    Science.gov (United States)

    Hernández-Arias, A. N.; Rodríguez-Méndez, B. G.; López-Callejas, R.; Valencia-Alvarado, R.; Mercado-Cabrera, A.; Peña-Eguiluz, R.; Barocio, S. R.; Muñoz-Castro, A. E.; de la Piedad Beneitez, A.

    2012-06-01

    The inactivation of Bacillus subtilis bacteria in water has been experimentally studied by means of a pulsed dielectric barrier discharge (PDBD) in a coaxial reactor endowed with an alumina dielectric. The plasma source is capable of operating at atmospheric pressure with gas, water or hybrid gas-liquid media at adjustable 25 kV pulses, 30 μs long and at a 500 Hz frequency. In order to evaluate the inactivation efficiency of the system, a set of experiments were designed on the basis of oxygen flow control. The initial data have showed a significant bacterial rate reduction of 103-107 CFU/mL. Additional results proved that applying an oxygen flow for a few seconds during the PDBD treatment inactivates the Bacillus subtilis population with 99.99% effectiveness. As a reference, without gas flow but with the same exposure times, this percentage is reduced to ~90%. The analysis of the relationship between inactivation rate and chemical species in the discharge has been carried out using optical emission spectroscopy as to identifying the main reactive species. Reactive oxygen species such as atomic oxygen and ozone tuned out to be the dominant germicidal species. Some proposed inactivation mechanisms of this technique are discussed.

  4. Pulsed dielectric barrier discharge for Bacillus subtilis inactivation in water

    International Nuclear Information System (INIS)

    Hernández-Arias, A N; López-Callejas, R; De la Piedad Beneitez, A; Rodríguez-Méndez, B G; Valencia-Alvarado, R; Mercado-Cabrera, A; Peña-Eguiluz, R; Barocio, S R; Muñoz-Castro, A E

    2012-01-01

    The inactivation of Bacillus subtilis bacteria in water has been experimentally studied by means of a pulsed dielectric barrier discharge (PDBD) in a coaxial reactor endowed with an alumina dielectric. The plasma source is capable of operating at atmospheric pressure with gas, water or hybrid gas-liquid media at adjustable 25 kV pulses, 30 μs long and at a 500 Hz frequency. In order to evaluate the inactivation efficiency of the system, a set of experiments were designed on the basis of oxygen flow control. The initial data have showed a significant bacterial rate reduction of 10 3 -10 7 CFU/mL. Additional results proved that applying an oxygen flow for a few seconds during the PDBD treatment inactivates the Bacillus subtilis population with 99.99% effectiveness. As a reference, without gas flow but with the same exposure times, this percentage is reduced to ∼90%. The analysis of the relationship between inactivation rate and chemical species in the discharge has been carried out using optical emission spectroscopy as to identifying the main reactive species. Reactive oxygen species such as atomic oxygen and ozone tuned out to be the dominant germicidal species. Some proposed inactivation mechanisms of this technique are discussed.

  5. The effects of brewery effluent discharge on the water quality and ...

    African Journals Online (AJOL)

    Effluent discharge into the river significantly altered the water quality. Monitoring of effluent discharge into the aquatic environment and strict adherence to regulatory limits will halt further degradation of the environment. Key words: Water, sediment physico-chemistry, distribution coefficient, effluent discharge, tropical river ...

  6. Discharge Fee Policy Analysis: A Computable General Equilibrium (CGE) Model of Water Resources and Water Environments

    OpenAIRE

    Guohua Fang; Ting Wang; Xinyi Si; Xin Wen; Yu Liu

    2016-01-01

    To alleviate increasingly serious water pollution and shortages in developing countries, various kinds of policies have been implemented by local governments. It is vital to quantify and evaluate the performance and potential economic impacts of these policies. This study develops a Computable General Equilibrium (CGE) model to simulate the regional economic and environmental effects of discharge fees. Firstly, water resources and water environment factors are separated from the input and out...

  7. Preparation of water-soluble carbon nanotubes using a pulsed streamer discharge in water

    International Nuclear Information System (INIS)

    Imasaka, Kiminobu; Suehiro, Junya; Kanatake, Yusuke; Kato, Yuki; Hara, Masanori

    2006-01-01

    A novel technique for the preparation of water-soluble carbon nanotubes was demonstrated using a pulsed streamer discharge generated in water. The technique involved chemical reactions between radicals generated by the pulsed streamer discharge and carbon nanotubes. The pulsed streamer-treated carbon nanotubes were homogeneously dispersed and well solubilized in water for a month or longer. The mechanism of solubilization of carbon nanotubes by the pulsed streamer discharge is discussed based on FTIR spectroscopy and optical emission spectra measurements. FTIR spectroscopy revealed that -OH groups, which are known to impart a hydrophilic nature to carbon material, were introduced on the carbon nanotube surface. Optical emission spectra from the pulsed streamer plasma showed that highly oxidative O * and H * radicals were generated in water. These results suggest that the functionalization of the carbon nanotube surface by -OH group can be attributed to the O * and H * radicals. An advantage of the proposed method is that there is no need for any chemical agents or additives for solubilization. Chemical agents for solubilization are generated from the water itself by the electrochemical reactions induced by the pulsed streamer discharge

  8. Sodium Bicarbonate mouth rinse: An Uncommon Complication

    OpenAIRE

    Fatih Mehmet Coskunses

    2012-01-01

    Sodium bicarbonate is a natural buffer that maintains a healthy pH in mouth to promote a clean and fresh oral environment. Sodium-bicarbonate rinse is empirically suggested to patients by dentist and people around, and may prove to be harmful. In this short communication, we present chemical burn of oral mucosa because of sodium-bicarbonate rinse after misfit dental impression.

  9. Structure design of water discharge surge tank of nuclear power plant

    International Nuclear Information System (INIS)

    Wang Fang; Hou Shuqiang

    2015-01-01

    Drainage is an important function of water discharge surge tank in nuclear power plant. There is little wall and beam inside the water discharge surge tank due to the requirement of major work, which is different from the general structure. Taking water discharge surge tank of nuclear power plant for example, concerned problems are expatiated in the structure scheme of water discharge surge tank, and important structural components are analyzed. Structural analysis model is established by ANSYS finite element analysis. A comprehensive and numerical analysis is performed for different combinations of structural model, and the internal force of structure is extracted. Finally, suggestions for design of similar structure are proposed. (authors)

  10. Comparison of trace metals in intake and discharge waters of power plants using clean techniques

    International Nuclear Information System (INIS)

    Salvito, D.T.; Allen, H.E.

    1995-01-01

    In order to determine the impact to receiving waters of trace metals potentially discharged from a once-through, non-contact cooling water system from a power plant, a study was conducted utilizing clean sampling and analytical techniques for a series of metals. Once-through, non-contact cooling water at power plants is frequently discharged back to the fresh or saline waterbody utilized for its intake water. This water is used to cool plant condensers. Intake and discharge data were collected and evaluated using paired t-tests. Study results indicate that there is no measurable contribution of metals from non-contact cooling water from this power plant

  11. Characteristics of meter-scale surface electrical discharge propagating along water surface at atmospheric pressure

    Czech Academy of Sciences Publication Activity Database

    Hoffer, Petr; Sugiyama, Y.; Hosseini, S.H.R.; Akiyama, H.; Lukeš, Petr; Akiyama, M.

    2016-01-01

    Roč. 49, č. 41 (2016), č. článku 415202. ISSN 0022-3727 Institutional support: RVO:61389021 Keywords : water surface * spectroscopy * high-speed photography * pulsed plasma discharge * Atmospheric - pressure plasmas * electric discharges * liquids * water Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 2.588, year: 2016 http://iopscience.iop.org/article/10.1088/0022-3727/49/41/415202

  12. Characteristics of meter-scale surface electrical discharge propagating along water surface at atmospheric pressure

    Czech Academy of Sciences Publication Activity Database

    Hoffer, Petr; Sugiyama, Y.; Hosseini, S.H.R.; Akiyama, H.; Lukeš, Petr; Akiyama, M.

    2016-01-01

    Roč. 49, č. 41 (2016), č. článku 415202. ISSN 0022-3727 Institutional support: RVO:61389021 Keywords : water surface * spectroscopy * high-speed photography * pulsed plasma discharge * Atmospheric-pressure plasmas * electric discharges * liquids * water Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 2.588, year: 2016 http://iopscience.iop.org/article/10.1088/0022-3727/49/41/415202

  13. Degradation of Verapamil hydrochloride in water by gliding arc discharge

    Czech Academy of Sciences Publication Activity Database

    Krishna, S.; Mašláni, Alan; Izdebski, T.; Horáková, M.; Klementová, Š.; Špatenka, P.

    2016-01-01

    Roč. 152, June (2016), s. 47-54 ISSN 0045-6535 Institutional support: RVO:61389021 Keywords : Gliding arc discharge * Emission spectroscopy * Pharmaceuticals * Half-life * Degradation mechanism Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 4.208, year: 2016 http://www.sciencedirect.com/science/article/pii/S0045653516302442

  14. Proposed test method for determining discharge rates from water closets

    DEFF Research Database (Denmark)

    Nielsen, V.; Fjord Jensen, T.

    At present the rates at which discharge takes place from sanitary appliances are mostly known only in the form of estimated average values. SBI has developed a measuring method enabling determination of the exact rate of discharge from a sanitary appliance as function of time. The methods depends...

  15. Discharge Fee Policy Analysis: A Computable General Equilibrium (CGE Model of Water Resources and Water Environments

    Directory of Open Access Journals (Sweden)

    Guohua Fang

    2016-09-01

    Full Text Available To alleviate increasingly serious water pollution and shortages in developing countries, various kinds of policies have been implemented by local governments. It is vital to quantify and evaluate the performance and potential economic impacts of these policies. This study develops a Computable General Equilibrium (CGE model to simulate the regional economic and environmental effects of discharge fees. Firstly, water resources and water environment factors are separated from the input and output sources of the National Economic Production Department. Secondly, an extended Social Accounting Matrix (SAM of Jiangsu province is developed to simulate various scenarios. By changing values of the discharge fees (increased by 50%, 100% and 150%, three scenarios are simulated to examine their influence on the overall economy and each industry. The simulation results show that an increased fee will have a negative impact on Gross Domestic Product (GDP. However, waste water may be effectively controlled. Also, this study demonstrates that along with the economic costs, the increase of the discharge fee will lead to the upgrading of industrial structures from a situation of heavy pollution to one of light pollution which is beneficial to the sustainable development of the economy and the protection of the environment.

  16. Biological effects from discharge of cooling water from thermal power plants

    International Nuclear Information System (INIS)

    1976-12-01

    Results are reported for a Danish project on biological effects from discharge of cooling water from thermal power plants. The purpose of the project was to provide an up-to-date knowledge of biological effects of cooling water discharge and of organization and evaluation of recipient investigations in planned and established areas. (BP)

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

    Science.gov (United States)

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

    2017-11-01

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

  18. Generation of ozone by pulsed corona discharge over water surface in hybrid gas-liquid electrical discharge reactor

    Energy Technology Data Exchange (ETDEWEB)

    Lukes, Petr [Department of Pulse Plasma Systems, Institute of Plasma Physics, Academy of Sciences of the Czech Republic, Za Slovankou 3, PO Box 17, 182 21 Prague 8 (Czech Republic); Clupek, Martin [Department of Pulse Plasma Systems, Institute of Plasma Physics, Academy of Sciences of the Czech Republic, Za Slovankou 3, PO Box 17, 182 21 Prague 8 (Czech Republic); Babicky, Vaclav [Department of Pulse Plasma Systems, Institute of Plasma Physics, Academy of Sciences of the Czech Republic, Za Slovankou 3, PO Box 17, 182 21 Prague 8 (Czech Republic); Janda, Vaclav [Department of Water Technology and Environmental Engineering, Institute of Chemical Technology, Technicka 5, 160 28 Prague 6 (Czech Republic); Sunka, Pavel [Department of Pulse Plasma Systems, Institute of Plasma Physics, Academy of Sciences of the Czech Republic, Za Slovankou 3, PO Box 17, 182 21 Prague 8 (Czech Republic)

    2005-02-07

    Ozone formation by a pulse positive corona discharge generated in the gas phase between a planar high voltage electrode made from reticulated vitreous carbon and a water surface with an immersed ground stainless steel plate electrode was investigated under various operating conditions. The effects of gas flow rate (0.5-3 litre min{sup -1}), discharge gap spacing (2.5-10 mm), applied input power (2-45 W) and gas composition (oxygen containing argon or nitrogen) on ozone production were determined. Ozone concentration increased with increasing power input and with increasing discharge gap. The production of ozone was significantly affected by the presence of water vapour formed through vaporization of water at the gas-liquid interface by the action of the gas phase discharge. The highest energy efficiency for ozone production was obtained using high voltage pulses of approximately 150 ns duration in Ar/O{sub 2} mixtures with the maximum efficiency (energy yield) of 23 g kW h{sup -1} for 40% argon content.

  19. Generation of ozone by pulsed corona discharge over water surface in hybrid gas-liquid electrical discharge reactor

    International Nuclear Information System (INIS)

    Lukes, Petr; Clupek, Martin; Babicky, Vaclav; Janda, Vaclav; Sunka, Pavel

    2005-01-01

    Ozone formation by a pulse positive corona discharge generated in the gas phase between a planar high voltage electrode made from reticulated vitreous carbon and a water surface with an immersed ground stainless steel plate electrode was investigated under various operating conditions. The effects of gas flow rate (0.5-3 litre min -1 ), discharge gap spacing (2.5-10 mm), applied input power (2-45 W) and gas composition (oxygen containing argon or nitrogen) on ozone production were determined. Ozone concentration increased with increasing power input and with increasing discharge gap. The production of ozone was significantly affected by the presence of water vapour formed through vaporization of water at the gas-liquid interface by the action of the gas phase discharge. The highest energy efficiency for ozone production was obtained using high voltage pulses of approximately 150 ns duration in Ar/O 2 mixtures with the maximum efficiency (energy yield) of 23 g kW h -1 for 40% argon content

  20. Characteristics and applications of diffuse discharge of water electrode in air

    Science.gov (United States)

    Wenzheng, LIU; Tahan, WANG; Xiaozhong, CHEN; Chuanlong, MA

    2018-01-01

    Plasma water treatment technology, which aims to produce strong oxidizing reactive particles that act on the gas-liquid interface by way of discharging, is used to treat the organic pollutants that do not degrade easily in water. This paper presents a diffuse-discharge plasma water treatment method, which is realized by constructing a conical air gap through an uneven medium layer. The proposed method uses water as one electrode, and a dielectric barrier discharge electrode is constructed by using an uneven dielectric. The electric field distribution in the discharge space will be uneven, wherein the long gap electric field will have a smaller intensity, while the short one will have a larger intensity. A diffuse glow discharge is formed in the cavity. With this type of plasma water treatment equipment, a methyl orange solution with a concentration of 10 mg l-1 was treated, and the removal rate was found to reach 88.96%.

  1. Study of a DC gas discharge with a copper cathode in a water flow

    Science.gov (United States)

    Tazmeev, G. Kh.; Timerkaev, B. A.; Tazmeev, Kh. K.

    2017-07-01

    A dc gas discharge between copper electrodes in the current range of 5-20 A was studied experimentally. The discharge gap length was varied within 45-70 mm. The cathode was a 10-mm-diameter rod placed in the water flowing out from a dielectric tube. Three discharge configurations differing in the position of the cathode upper end with respect to the water surface were considered: (i) above water; (ii) flush with the water surface, and (iii) under water. The electric and optical characteristics of the discharge in the second configuration were studied in more detail. It is established that the discharge properties are similar to those of an electric arc. Considerable cathode erosion was observed in the third configuration. It is revealed that fine-dispersed copper grains form in the course of erosion.

  2. Discharge, water temperature, and water quality of Warm Mineral Springs, Sarasota County, Florida: A retrospective analysis

    Science.gov (United States)

    Metz, Patricia A.

    2016-09-27

    Warm Mineral Springs, located in southern Sarasota County, Florida, is a warm, highly mineralized, inland spring. Since 1946, a bathing spa has been in operation at the spring, attracting vacationers and health enthusiasts. During the winter months, the warm water attracts manatees to the adjoining spring run and provides vital habitat for these mammals. Well-preserved late Pleistocene to early Holocene-age human and animal bones, artifacts, and plant remains have been found in and around the spring, and indicate the surrounding sinkhole formed more than 12,000 years ago. The spring is a multiuse resource of hydrologic importance, ecological and archeological significance, and economic value to the community.The pool of Warm Mineral Springs has a circular shape that reflects its origin as a sinkhole. The pool measures about 240 feet in diameter at the surface and has a maximum depth of about 205 feet. The sinkhole developed in the sand, clay, and dolostone of the Arcadia Formation of the Miocene-age to Oligocene-age Hawthorn Group. Underlying the Hawthorn Group are Oligocene-age to Eocene-age limestones and dolostones, including the Suwannee Limestone, Ocala Limestone, and Avon Park Formation. Mineralized groundwater, under artesian pressure in the underlying aquifers, fills the remnant sink, and the overflow discharges into Warm Mineral Springs Creek, to Salt Creek, and subsequently into the Myakka River. Aquifers described in the vicinity of Warm Mineral Springs include the surficial aquifer system, the intermediate aquifer system within the Hawthorn Group, and the Upper Floridan aquifer in the Suwannee Limestone, Ocala Limestone, and Avon Park Formation. The Hawthorn Group acts as an upper confining unit of the Upper Floridan aquifer.Groundwater flow paths are inferred from the configuration of the potentiometric surface of the Upper Floridan aquifer for September 2010. Groundwater flow models indicate the downward flow of water into the Upper Floridan aquifer

  3. effect of land use on water discharge in humid regions

    African Journals Online (AJOL)

    LUCY

    From the Pearson's Product Moment correlation analysis of the relationship ... mean discharge measurement in the basin, the result shows a strong negative relationship with r = - ..... presented at the British Ecological .... Peninsular Malaysia.

  4. The Rayleigh-Taylor instability under electrical pulse discharge in water

    International Nuclear Information System (INIS)

    Kononov, A.V.; Porytskyy, P.V.; Starchyk, P.D.; Voitenko, L.M.

    1999-01-01

    The development of the Rayleigh-Taylor instability is studied on the interface between both the plasma channel and liquid medium under an electrical pulse discharge in water.It is shown that,growth of the irregularities of the contact interface leads to the increasing of heat flux from the discharge channel due to the growth of an interfacial area and the incoming of water matter into a discharge channel.As a result of these processes the characteristics of the discharge may be strongly varied

  5. THE EFFECT OF MOUTH RINSES ON THE COLOR STABILITY OF SONICFILL AND A NANOHYBRID COMPOSITE

    Directory of Open Access Journals (Sweden)

    Tuğba Toz-Akalın

    2016-04-01

    Full Text Available Purpose: The aim of this study was to evaluate the effects of 4 mouth rinses on the color stability of two different resin composites. Materials and Methods: A2 shade sonic-activated bulk fill material SonicFill (Kerr and conventional nanohybrid composite Filtek Z550 (3M ESPE were used. Forty disc-shaped specimens (10 mm x 2 mm were fabricated for both composites and finished using 400-grit SiC paper and polished. After polishing and immersing in distilled water for 24h all specimens were subjected to color measurements. The baseline color values (L*, a*, b* of each specimen were measured with a colorimeter. Following baseline measurement each composite group was divided into 5 groups: Oral-B Pro Expert Clinic Line Alcoholfree (Oral-B group, Listerine Tooth Defense Rinse (Listerine group, Pharmol Zn Mouth rinse (Çözümilaç group, Nilera Mouth rinse (Nilera group and Distilled water (control group. The specimens were incubated in mouth rinses (20 ml at 37°C for 12 hours and subjected to color measurement. Two-way ANO VA was used for statistical analysis (p<0.05. Results: SonicFill showed significantly higher discoloration when exposed to Oral-B Pro Expert Clinic Line Alcohol-free, Listerine Tooth Defense Rinse and Pharmol Zn Mouth rinse. The color differences of two resin composites were not statistically significant for distilled water and Nilera Mouth rinse. Conclusion: Within the limits of this study it can be concluded that the SonicFill showed higher discoloration than nanohybrid resin composite Filtek Z550.

  6. Discharge, sediment, and water chemistry in Clear Creek, western Nevada, water years 2013–16

    Science.gov (United States)

    Huntington, Jena M.; Riddle, Daniel J.; Paul, Angela P.

    2018-05-01

    Clear Creek is a small stream that drains the eastern Carson Range near Lake Tahoe, flows roughly parallel to the Highway 50 corridor, and discharges to the Carson River near Carson City, Nevada. Historical and ongoing development in the drainage basin is thought to be affecting Clear Creek and its sediment-transport characteristics. Previous studies from water years (WYs) 2004 to 2007 and from 2010 to 2012 evaluated discharge, selected water-quality parameters, and suspended-sediment concentrations, loads, and yields at three Clear Creek sampling sites. This report serves as a continuation of the data collection and analyses of the Clear Creek discharge regime and associated water-chemistry and sediment concentrations and loads during WYs 2013–16.Total annual sediment loads ranged from 870 to 5,300 tons during WYs 2004–07, from 320 to 1,770 tons during WYs 2010–12, and from 50 to 200 tons during WYs 2013–16. Ranges in annual loads during the three study periods were not significantly different; however, total loads were greater during 2004–07 than they were during 2013–16. Annual suspended-sediment loads in WYs 2013–16 showed no significant change since WYs 2010–12 at sites 1 (U.S. Geological Survey reference site 10310485; Clear Creek above Highway 50, near Spooner Summit, Nevada) or 2 (U.S. Geological Survey streamgage 10310500; Clear Creek above Highway 50, near Spooner Summit, Nevada), but significantly lower loads at site 3 (U.S. Geological Survey site 10310518; Clear Creek at Fuji Park, at Carson City, Nevada), supporting the theory of sediment deposition between sites 2 and 3 where the stream gradient becomes more gradual. Currently, a threshold discharge of about 3.3 cubic feet per second is required to mobilize streambed sediment (bedload) from site 2 in Clear Creek. Mean daily discharge was significantly lower in 2010–12 than in 2004–07 and also significantly lower in 2013–16 than in 2010–12. During this study, lower bedload, and

  7. Yield of Ozone, Nitrite Nitrogen and Hydrogen Peroxide Versus Discharge Parameter Using APPJ Under Water

    International Nuclear Information System (INIS)

    Chen Bingyan; Wen Wen; Zhu Changping; Wang Yuan; Gao Ying; Fei Juntao; He Xiang; Yin Cheng; Jiang Yongfeng; Chen Longwei

    2016-01-01

    Discharge plasma in and in contact with water can be accompanied with ultraviolet radiation and electron impact, thus can generate hydroxyl radicals, ozone, nitrite nitrogen and hydrogen peroxide. In this paper, a non-equilibrium plasma processing system was established by means of an atmospheric pressure plasma jet immersed in water. The hydroxyl intensities and discharge energy waveforms were tested. The results show that the positive and negative discharge energy peaks were asymmetric, where the positive discharge energy peak was greater than the negative one. Meanwhile, the yield of ozone and nitrite nitrogen was enhanced with the increase of both the treatment time and the discharge energy. Moreover, the pH value of treated water was reduced rapidly and maintained at a lower level. The residual concentration of hydrogen peroxide in APPJ treated water was kept at a low level. Additionally, both the efficiency energy ratio of the yield of ozone and nitrite nitrogen and that of the removal of p-nitrophenol increased as a function of discharge energy and discharge voltage. The experimental results were fully analyzed and the chemical reaction equations and the physical processes of discharges in water were given. (paper)

  8. The effect of rinsing time periods on wettability of elastomeric impression materials: in vitro study

    Directory of Open Access Journals (Sweden)

    Özlem Acar

    2016-01-01

    Full Text Available OBJECTIVE: The aim of this study was to determine whether different rinsing time periods affected the wettability of polymerized elastomeric impression materials. MATERIALS AND METHOD: Panasil Contact Plus (PCP, Panasil Contact Non-Surfactant (PCNS, Panasil Initial Contact (PIC, Express (EXP and Impregum (IMP impression materials were tested. Standardized samples were rinsed with water for 10 s, 15 s or 20 s, and the wettability was determined by contact angle measurement through an evaluation period of 60 seconds (n=7. Non-rinsed groups were used as control. Measurements were made at 5 time points (at 0, 6, 15, 30 and 60 seconds. Kruskal Wallis test and Conover’s multiple comparison tests were used for all multiple comparisons. Bonferroni adjustment was applied for controlling Type I error (p0.002. CONCLUSION: Rinsing the surfactant-containing polyvinylsiloxane impression materials decreased their wettability, whereas no such effect was seen for the surfactant free polyvinylsiloxane and polyether impression materials.

  9. Estimation of combined sewer overflow discharge: a software sensor approach based on local water level measurements.

    Science.gov (United States)

    Ahm, Malte; Thorndahl, Søren; Nielsen, Jesper E; Rasmussen, Michael R

    2016-12-01

    Combined sewer overflow (CSO) structures are constructed to effectively discharge excess water during heavy rainfall, to protect the urban drainage system from hydraulic overload. Consequently, most CSO structures are not constructed according to basic hydraulic principles for ideal measurement weirs. It can, therefore, be a challenge to quantify the discharges from CSOs. Quantification of CSO discharges are important in relation to the increased environmental awareness of the receiving water bodies. Furthermore, CSO discharge quantification is essential for closing the rainfall-runoff mass-balance in combined sewer catchments. A closed mass-balance is an advantage for calibration of all urban drainage models based on mass-balance principles. This study presents three different software sensor concepts based on local water level sensors, which can be used to estimate CSO discharge volumes from hydraulic complex CSO structures. The three concepts were tested and verified under real practical conditions. All three concepts were accurate when compared to electromagnetic flow measurements.

  10. Fate and effects of nearshore discharges of OCS produced waters. Volume 2. Technical report (Final)

    International Nuclear Information System (INIS)

    Rabalais, N.N.; McKee, B.A.; Reed, D.J.; Means, J.C.

    1991-06-01

    While the number of facilities that discharge OCS produced waters into coastal environments of Louisiana are few in number, they account for large volumes, individually and collectively. Of the 15 facilities which discharge OCS-generated produced water into coastal environments of Louisiana (as of February 1990), 10 discharges in seven areas were studied. The discharge volumes of the study areas range from 3,000 to 106,000/bbl.d. The receiving environments for these effluents are varied, but include the shallow, nearshore continental shelf; high energy, freshwater distributaries of the Mississippi River delta; and brackish and saline coastal environments with moderately to poorly flushed waters. All study areas are within the Mississippi River Deltaic Plain. The study expanded on the initial assessment of Boesch and Rabalais (1989a) with increased temporal and spatial studies of three areas, additional study sites including an abandoned discharge, and additional analytical and field observations

  11. Time-resolved processes in a pulsed electrical discharge in argon bubbles in water

    Science.gov (United States)

    Gershman, S.; Belkind, A.

    2010-12-01

    A phenomenological picture of a pulsed electrical discharge in gas bubbles in water is produced by combining electrical, spectroscopic, and imaging characterization methods. The discharge is generated by applying 1 μ s pulses of 5 to 20 kV between a needle and a disk electrode submerged in water. An Ar gas bubble surrounds the tip of the needle electrode. Imaging, electrical characteristics, and time-resolved optical emission spectroscopic data suggest a fast streamer propagation mechanism and the formation of a plasma channel in the bubble. Comparing the electrical and imaging data for consecutive pulses applied to the bubble at a frequency of 1 Hz indicates that each discharge proceeds as an entirely new process with no memory of the previous discharge aside from the presence of long-lived chemical species, such as ozone and oxygen. Imaging and electrical data show the presence of two discharge events during each applied voltage pulse, a forward discharge near the beginning of the applied pulse depositing charge on the surface of the bubble and a reverse discharge removing the accumulated charge from the water/gas interface when the applied voltage is turned off. The pd value of ~ 300-500 torr cm, the 1 μs long pulse duration, low repetition rate, and unidirectional character of the applied voltage pulses make the discharge process here unique compared to the traditional corona or dielectric barrier discharges.

  12. Waste water discharges into natural waters; Problematiche sulla dispersione di effluenti liquidi da canali o condotte a pelo liquido

    Energy Technology Data Exchange (ETDEWEB)

    Marri, P [ENEA, Centro Ricerche Santa Teresa, La Spezia (Italy). Dip. Ambiente; Barsanti, P; Mione, A; Posarelli, M [ENEA, Centro Ricerche Casaccia, Rome (Italy). Dip. Ambiente

    1996-12-01

    The acqueous discharges into natural waters is a very technical solution expecially for surface buoyant discharges. It is not only convenient to limit the concentration levels of the discharges, but also to improve the turbolent processes that diluite the discharge. Mostly these processes depend by some geometric parameters of the discharge and by some physical parameters of the effluent and of the receiving water body. An appropriate choice of some parameters, using also suitable mathematical models, allows to design discharges with a very high dilution; so the decreasing of the pollutant levels is improved and the environmental impact can be reduced versus a not diluted effluent. The simulations of a mathematical model, here described, prove that in some circumstances, expecially in case of discharges of fresh water into saline water bodies with a low velocity of the current, the dilution is poor; the effluent can be trapped in a narrow water surface layer where the pollutant concentrations remain high. also far away from the discharge point.

  13. Cetylpyridinium chloride mouth rinses alleviate experimental gingivitis by inhibiting dental plaque maturation.

    Science.gov (United States)

    Teng, Fei; He, Tao; Huang, Shi; Bo, Cun-Pei; Li, Zhen; Chang, Jin-Lan; Liu, Ji-Quan; Charbonneau, Duane; Xu, Jian; Li, Rui; Ling, Jun-Qi

    2016-09-29

    Oral rinses containing chemotherapeutic agents, such as cetylpyridinium chloride (CPC), can alleviate plaque-induced gingival infections, but how oral microbiota respond to these treatments in human population remains poorly understood. Via a double-blinded, randomised controlled trial of 91 subjects, the impact of CPC-containing oral rinses on supragingival plaque was investigated in experimental gingivitis, where the subjects, after a 21-day period of dental prophylaxis to achieve healthy gingivae, received either CPC rinses or water for 21 days. Within-subject temporal dynamics of plaque microbiota and symptoms of gingivitis were profiled via 16S ribosomal DNA gene pyrosequencing and assessment with the Mazza gingival index. Cetylpyridinium chloride conferred gingival benefits, as progression of gingival inflammation resulting from a lack of dental hygiene was significantly slower in the mouth rinse group than in the water group due to inhibition of 17 gingivitis-enriched bacterial genera. Tracking of plaque α and β diversity revealed that CPC treatment prevents acquisition of new taxa that would otherwise accumulate but maintains the original biodiversity of healthy plaques. Furthermore, CPC rinses reduced the size, local connectivity and microbiota-wide connectivity of the bacterial correlation network, particularly for nodes representing gingivitis-enriched taxa. The findings of this study provide mechanistic insights into the impact of oral rinses on the progression and maturation of dental plaque in the natural human population.

  14. Low-dielectric layer increases nanosecond electric discharges in distilled water

    KAUST Repository

    Hamdan, Ahmad; Cha, Min

    2016-01-01

    decreasing of the energy consumption are the main goals of today’s research. Here we present an experimental study of nanosecond discharge in distilled water covered by a layer of dielectric material. We demonstrate through this paper that the discharge

  15. Utilization of ultraviolet radiation of cold hollow cathode discharge plasma for water disinfection

    International Nuclear Information System (INIS)

    Soloshenko, I.O.; Bazhenov, V.Yu.; Khomych, V.O.; Tsiolko, V.V.; Potapchenko, N.G.; Goncharuk, V.V.

    2006-01-01

    We study the possibility to use the ultraviolet radiation of a hollow cathode discharge plasma for water disinfection. We have performed the comparative experiments on the influence of ultraviolet radiation of the mentioned discharge plasma, as well as that of a standard low pressure mercury lamp

  16. Overvoltage effect on electrical discharge type in medium-conductivity water in inhomogeneous pulsed electric field

    Science.gov (United States)

    Panov, V. A.; Vasilyak, L. M.; Pecherkin, V. Ya; Vetchinin, S. P.; Son, E. E.

    2018-01-01

    The transition between thermal and streamer discharges has been observed experimentally in water solution with conductivity 100 μS/cm applying positive voltage pulses to pin-to-rod electrodes. The transition happens at five-fold pulse amplitude. Considering streamer propagation as an ionization wave helped to establish relation between the parameters governing transition from one to another discharge mechanism.

  17. Development of high pressure rinsing set up for 650 MHz, 5- cell superconducting RF cavity cleaning

    International Nuclear Information System (INIS)

    Suhane, S.K.; Chauhan, S.K.; Bose, A.; Kokil, S.V.; Rajput, D.S.; Oraon, B.; Md Hussain; Sahu, A.; Raghavendra, S.; Joshi, S.C.

    2015-01-01

    High pressure rinsing (HPR) is an ultra-cleanliness process for the surface preparation of high field superconducting RF cavities. Any dust particle or chemical residue on the interior of cavity causes field emission. Jets of high pressure (80-100 bar) ultra pure water dislodge surface contaminants that normally resist removal with conventional rinsing procedures, leading to substantial reduction in field emission and better cavity performance. For cleaning of 650 MHz, 5-cell SRF cavities, a high pressure rinsing set up has been developed at RRCAT. The HPR tool has a rotating wand coaxial with the vertically mounted SRF cavity that is moving up and down. Fan style spray nozzles are attached to the end of the rotating wand and the water jets emerging from spray nozzles scan the entire internal surface of the cavity. The set-up was installed in a specially built clean area meeting cleanliness class 100 standards. The ultrapure water with resistivity 2 ≥ 18 MΩ-cm required for rinsing is obtained from a dedicated water purification system installed for this purpose. The paper describes the salient design and constructional details of the high pressure rinsing set up. Characterization of water jet parameters based on the momentum transfer between the water jet and a load cell is also presented. (author)

  18. Fast imaging of intermittent electrospraying of water with positive corona discharge

    International Nuclear Information System (INIS)

    Pongrác, B; Janda, M; Martišovitš, V; Machala, Z; Kim, H H

    2014-01-01

    The effect of the electrospraying of water in combination with a positive direct current (dc) streamer corona discharge generated in air was investigated in this paper. We employed high-speed camera visualizations and oscilloscopic discharge current measurements in combination with an intensified charge-coupled device camera for fast time-resolved imaging. The repetitive process of Taylor cone formation and droplet formation from the mass fragments of water during the electrospray was visualized. Depending on the applied voltage, the following intermittent modes of electrospraying typical for water were observed: dripping mode, spindle mode, and oscillating-spindle mode. The observed electrospraying modes were repetitive with a frequency of a few hundreds of Hz, as measured from the fast image sequences. This frequency agreed well with the frequency of the measured streamer current pulses. The presence of filamentary streamer discharges at relatively low voltages probably prevented the establishment of a continuous electrospray in the cone–jet mode. After each streamer, a positive glow corona discharge was established on the water filament tip, and it propagated from the stressed electrode along with the water filament elongation. The results show a reciprocal character of intermittent electrospraying of water, and the presence of corona discharge, where both the electrospray and the discharge affect each other. The generation of a corona discharge from the water cone depended on the repetitive process of the cone formation. Also, the propagation and curvature of the water filament were influenced by the discharge and its resultant space charge. Furthermore, these phenomena were partially influenced by the water conductivity. (paper)

  19. Sinus Rinsing and Neti Pots

    Science.gov (United States)

    ... not to be used for routine or emergency drinking water disinfection. We have added an extra amount of bleach ... not to be used for routine or emergency drinking water disinfection. As mentioned above, we have added an extra ...

  20. Produced water discharges to the Gulf of Mexico: Background information for ecological risk assessments

    International Nuclear Information System (INIS)

    Meinhold, A.F.; Holtzman, S.; DePhillips, M.P.

    1996-06-01

    This report reviews ecological risk assessment concepts and methods; describes important biological resources in the Gulf of Mexico of potential concern for produced water impacts; and summarizes data available to estimate exposure and effects of produced water discharges. The emphasis is on data relating to produced water discharges in the central and western Gulf of Mexico, especially in Louisiana. Much of the summarized data and cited literature are relevant to assessments of impacts in other regions. Data describing effects on marine and estuarine fishes, mollusks, crustaceans and benthic invertebrates are emphasized. This review is part of a series of studies of the health and ecological risks from discharges of produced water to the Gulf of Mexico. These assessments will provide input to regulators in the development of guidelines and permits, and to industry in the use of appropriate discharge practices

  1. Produced water discharges to the Gulf of Mexico: Background information for ecological risk assessments

    Energy Technology Data Exchange (ETDEWEB)

    Meinhold, A.F.; Holtzman, S.; DePhillips, M.P.

    1996-06-01

    This report reviews ecological risk assessment concepts and methods; describes important biological resources in the Gulf of Mexico of potential concern for produced water impacts; and summarizes data available to estimate exposure and effects of produced water discharges. The emphasis is on data relating to produced water discharges in the central and western Gulf of Mexico, especially in Louisiana. Much of the summarized data and cited literature are relevant to assessments of impacts in other regions. Data describing effects on marine and estuarine fishes, mollusks, crustaceans and benthic invertebrates are emphasized. This review is part of a series of studies of the health and ecological risks from discharges of produced water to the Gulf of Mexico. These assessments will provide input to regulators in the development of guidelines and permits, and to industry in the use of appropriate discharge practices.

  2. Revisions to the Clean Water Act Regulatory Definition of Discharge of Dredged Material; Final Rule

    Science.gov (United States)

    The U.S. Army Corps of Engineers (Corps) and the Environmental Protection Agency (EPA) promulgated a final rule Amending a Clean Water Act (CWA) section 404 regulation that defines the term discharge of dredged material.

  3. Dynamics of bubble generated by low energy pulsed electric discharge in water

    International Nuclear Information System (INIS)

    Pinchuk, M E; Kolikov, V A; Rutberg, Ph G; Leks, A G; Dolinovskaya, R V; Snetov, V N; Stogov, A Yu

    2012-01-01

    Results of investigations of bubble formation and dynamics for discharge in water are presented. Experiments were carried out in discharge chamber with axisymmetric electrode system “wire to wire”. Interelectrode gap was varied from 1 to 10 mm. Energy in a pulse was <1 J. Velocity of bubble expantion and collapse is about several hundreds meter per second at early stage of discharge. Bubble pulsation period is 0.5 – 1 ms. Increasing of energy released in the discharge gap will increase bubble pulsation period. Little bubble was formed by reducing energy input into discharge. But the main stage of discharge always followed by bubble formation. Specific erosion is measured for different energy in pulse and matched up with bubble collapse.

  4. Assessing natural and anthropogenic influences on water discharge and sediment load in the Yangtze River, China.

    Science.gov (United States)

    Zhao, Yifei; Zou, Xinqing; Liu, Qing; Yao, Yulong; Li, Yali; Wu, Xiaowei; Wang, Chenglong; Yu, Wenwen; Wang, Teng

    2017-12-31

    The water discharge and sediment load of rivers are changing substantially under the impacts of climate change and human activities, becoming a hot issue in hydro-environmental research. In this study, the water discharge and sediment load in the mainstream and seven tributaries of the Yangtze River were investigated by using long-term hydro-meteorological data from 1953 to 2013. The non-parametric Mann-Kendall test and double mass curve (DMC) were used to detect trends and abrupt change-points in water discharge and sediment load and to quantify the effects of climate change and human activities on water discharge and sediment load. The results are as follows: (1) the water discharge showed a non-significant decreasing trend at most stations except Hukou station. Among these, water discharge at Dongting Lake and the Min River basin shows a significant decreasing trend with average rates of -13.93×10 8 m 3 /year and -1.8×10 8 m 3 /year (PYangtze River. (2) No significant abrupt change-points were detected in the time series of water discharge for all hydrological stations. In contrast, significant abrupt change-points were detected in sediment load, most of these changes appeared in the late 1980s. (3) The water discharge was mainly influenced by precipitation in the Yangtze River basin, whereas sediment load was mainly affected by climate change and human activities; the relative contribution ratios of human activities were above 70% for the Yangtze River. (4) The decrease of sediment load has directly impacted the lower Yangtze River and the delta region. These results will provide a reference for better resource management in the Yangtze River Basin. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. A licence to discharge cooling waters in tidal rivers, examplified by the 'Nuclear Power Station Unterweser'

    International Nuclear Information System (INIS)

    Kunz, H.

    1976-01-01

    Illustrated by the example of the lower Weser, aspects for automatic control, supervision measurements, and measurements for the securing of evidence, all in connection with cooling water discharges, are presented. The particularities of tidal rivers and the conditions for measuring systems resulting therefrom are explained. The cooling water discharge of the Kernkraftwerk Unterweser has been assigned an extensive measurement system for the automatic compilation of hydrologic data. The measurement systems design, the measurement stations, and the central station are described. (orig.) [de

  6. Cooling water intake and discharge facilities for Ikata Nuclear Power Station

    International Nuclear Information System (INIS)

    Ishihara, Hisashi; Iwabe, Masakazu

    1977-01-01

    Igata Nuclear Power Station is located at the root of Sadamisaki peninsula in the western part of Ehime Prefecture, Japan, and faces the Iyonada sea area in Seto Inland Sea. The most part of the shoreline forms the cliffs, and the bottom of the sea is rather steep, reaching 60 m depth at 300 m offshore. Considering warm water discharge measures in addition to the natural conditions of tide and current, temperature of sea water, water quality and wave data, it was decided that the deep layer intake system using bottom laid intake pipes and the submerged discharge system with caisson penetrable dike would be adopted for cooling water. The latter was first employed in Japan, and the submerged discharge system with caisson penetrable dike had been developed. The intake was designed to take sea water of about 38 m 3 per sec for each condenser unit at the depth of approximately 17 m with 4.8 m diameter and 116 m length pipes and its calculation details and construction are described. The discharge system was designed to provide a horseshoe-shaped discharge pond with inner diameter of approximately 50 m, surrounded by 17 concrete caissons, and to spout warm water discharge from eight openings of 1.58 m diameter, at the location of approximately 300 m eastward of the intake. Its hydraulic studies and model experiments and its construction are reported. (Wakatsuki, Y.)

  7. An investigation of an underwater steam plasma discharge as alternative to air plasmas for water purification

    International Nuclear Information System (INIS)

    Gucker, Sarah N; Foster, John E; Garcia, Maria C

    2015-01-01

    An underwater steam plasma discharge, in which water itself is the ionizing media, is investigated as a means to introduce advanced oxidation species into contaminated water for the purpose of water purification. The steam discharge avoids the acidification observed with air discharges and also avoids the need for a feed gas, simplifying the system. Steam discharge operation did not result in a pH changes in the processing of water or simulated wastewater, with the actual pH remaining roughly constant during processing. Simulated wastewater has been shown to continue to decompose significantly after steam treatment, suggesting the presence of long-lived plasma produced radicals. During steam discharge operation, nitrate production is limited, and nitrite production was found to be below the detection threshold of (roughly 0.2 mg L −1 ). The discharge was operated over a broad range of deposited power levels, ranging from approximately 30 W to 300 W. Hydrogen peroxide production was found to scale with increasing power. Additionally, the hydrogen peroxide production efficiency of the discharge was found to be higher than many of the rates reported in the literature to date. (paper)

  8. Synergistic effect of pulsed corona discharges and ozonation on decolourization of methylene blue in water

    Energy Technology Data Exchange (ETDEWEB)

    Malik, Muhammad Arif [Applied Chemistry Division, PINSTECH, PO Nilore, Islamabad (Pakistan); Ubaid-ur-Rehman [Applied Chemistry Division, PINSTECH, PO Nilore, Islamabad (Pakistan); Ghaffar, Abdul; Ahmed, Kurshid [Electronics Division, PINSTECH, PO Nilore, Islamabad (Pakistan)

    2002-08-01

    The effect of O{sub 2} and O{sub 3} bubbling on decolourization of methylene blue by pulsed corona discharges in water was studied. The pulsed corona discharges were produced by charging an 80 pF capacitor with a 40 kV DC source, through a 100 M{omega} resistor, and discharging it into a needle-plate type reactor at 60 Hz through a rotating spark gap switch. A 20 ml sample of 13.25 mg l{sup -1} methylene blue in distilled water was decolourized in 120 min. Bubbling O{sub 2} at 10 ml min{sup -1} through the discharge region reduced the decolourization time to 25 min. Bubbling O{sub 2} containing 1500 {mu}mol O{sub 3} l{sup -1} at 10 ml min{sup -1} reduced the decolourization time to 8 min. The O{sub 3} was produced by fractionating input energy between a water treatment reactor and a O{sub 3} generator, i.e. no additional energy was consumed for O{sub 3} production. Under the same experimental conditions methylene blue solution in tap water was decolourized in >210 min by corona discharge in solution, in 30 min by corona discharge with O{sub 2} bubbling, and in 11 min by corona discharge with bubbling of O{sub 2} containing 1500 {mu}mol O{sub 3} l{sup -1}.

  9. Synergistic effect of pulsed corona discharges and ozonation on decolourization of methylene blue in water

    International Nuclear Information System (INIS)

    Malik, Muhammad Arif; Ubaid-ur-Rehman; Ghaffar, Abdul; Ahmed, Kurshid

    2002-01-01

    The effect of O 2 and O 3 bubbling on decolourization of methylene blue by pulsed corona discharges in water was studied. The pulsed corona discharges were produced by charging an 80 pF capacitor with a 40 kV DC source, through a 100 MΩ resistor, and discharging it into a needle-plate type reactor at 60 Hz through a rotating spark gap switch. A 20 ml sample of 13.25 mg l -1 methylene blue in distilled water was decolourized in 120 min. Bubbling O 2 at 10 ml min -1 through the discharge region reduced the decolourization time to 25 min. Bubbling O 2 containing 1500 μmol O 3 l -1 at 10 ml min -1 reduced the decolourization time to 8 min. The O 3 was produced by fractionating input energy between a water treatment reactor and a O 3 generator, i.e. no additional energy was consumed for O 3 production. Under the same experimental conditions methylene blue solution in tap water was decolourized in >210 min by corona discharge in solution, in 30 min by corona discharge with O 2 bubbling, and in 11 min by corona discharge with bubbling of O 2 containing 1500 μmol O 3 l -1

  10. Identification of ballast water discharge profiles of a port to enable effective ballast water management and environmental studies

    Science.gov (United States)

    David, Matej; Gollasch, Stephan; Penko, Ludvik

    2018-03-01

    Information about the profile of ballast water discharges in a port is one of the basic elements of the decision making process in ballast water risk assessment and management, and supports the evaluation of dimensions and processes of aquatic species invasions with vessels ballast water. In the lack of ballast water reporting, ballast water discharge assessments need to be conducted. In this study we have assessed and compared ballast water discharge profiles of two ports with different maritime traffic and cargo profiles, the Port of Hamburg (Germany) and the Muuga Harbour, Port of Tallinn (Estonia). This study shows methods and approaches which can be used to assess volumes and donor ports of ballast water discharges for a port at the level of each vessel call. These methods and approaches can be applied to any port to support the implementation of feasible and efficient ballast water management measures and to enable environmental studies including long-term accumulation risks of disinfection by-products from ballast water management systems making use of active substances, as well as for discharges of other chemical compounds.

  11. 77 FR 17082 - Standards for Living Organisms in Ships' Ballast Water Discharged in U.S. Waters: Final...

    Science.gov (United States)

    2012-03-23

    ... standard will be used to approve ballast water management methods that are effective in preventing or reducing the introduction of nonindigenous species via discharged ballast water into waters of the United....regulations.gov on or before April 23, 2012 or reach the Docket Management Facility by that date. ADDRESSES...

  12. Effect of land cover, stream discharge, and precipitation on water quality in Puerto Rico

    Science.gov (United States)

    Hall, J. S.; Uriarte, M.

    2017-12-01

    In 2015, Puerto Rico experienced one of the worst droughts in its history, causing widespread water rationing and sparking concerns for future resources. The drought represents precipitation extremes that provide valuable insight into the effects of land cover (LC), on modulating discharge and water quality indices at varying spatial scales. We used data collected from 38 water quality and 55 precipitation monitoring stations in Puerto Rico from 2005 to 2016, paired with a 2010 land cover map to (1) determine whether temporal variability in discharge, precipitation, or antecedent precipitation was a better predictor of water quality, (2) find the spatial scale where LC has the greatest impact on water quality, and (3) quantify impacts of LC on water quality indices, including dissolved oxygen (mg/L), total nitrogen (mg/L), phosphorous (mg/L), turbidity (NTRU), fecal coliforms (colony units/100mL) and instantaneous discharge (ft3/s). The resulting linear mixed effects models account for between 36-68% of the variance in water quality. Preliminary results indicate that phosphorous and nitrogen were best predicted from instantaneous stream discharge, the log of discharge was the better predictor for turbidity and fecal coliforms, and summed 2 and 14-day antecedent precipitation indices were better predictors for dissolved oxygen and discharge, respectively. Increased urban and pasture area reliably decreased water quality in relation to forest cover, while agriculture and wetlands had little or mixed effects. Turbidity and nitrogen responded to a watershed level LC, while phosphorous, fecal coliforms, and discharge responded to LC in 60 m riparian buffers at the watershed scale. Our results indicate that LC modulates changing precipitation regimes and the ensuing impacts on water quality at a range of spatial scales.

  13. Characteristics of ultraviolet light and radicals formed by pulsed discharge in water

    Science.gov (United States)

    Sun, Bing; Kunitomo, Shinta; Igarashi, Chiaki

    2006-09-01

    In this investigation, the ultraviolet light characteristics and OH radical properties produced by a pulsed discharge in water were studied. For the plate-rod reactor, it was found that the ultraviolet light energy has a 3.2% total energy injected into the reactor. The ultraviolet light changed with the peak voltage and electrode distance. UV characteristics in tap water and the distilled water are given. The intensity of the OH radicals was the highest for the 40 mm electrode distance reactor. In addition, the properties of hydrogen peroxide and ozone were also studied under arc discharge conditions. It was found that the OH radicals were in the ground state and the excited state when a pulsed arc discharge was used. The ozone was produced by the arc discharge even if the oxygen gas is not bubbled into the reactor. The ozone concentration produces a maximum value with treatment time.

  14. Characteristics of ultraviolet light and radicals formed by pulsed discharge in water

    Energy Technology Data Exchange (ETDEWEB)

    Sun Bing [Dalian Maritime University, College of Environment, 1st Linghai Road, Dalian (China); Kunitomo, Shinta [Ebara Corporation, 1-6-27, Konan, Minato-ku 108-8480 (Japan); Igarashi, Chiaki [Ebara Research Co. Ltd, 2-1, Honfujisawa 4-chome, Fujisawa 251-8502 (Japan)

    2006-09-07

    In this investigation, the ultraviolet light characteristics and OH radical properties produced by a pulsed discharge in water were studied. For the plate-rod reactor, it was found that the ultraviolet light energy has a 3.2% total energy injected into the reactor. The ultraviolet light changed with the peak voltage and electrode distance. UV characteristics in tap water and the distilled water are given. The intensity of the OH radicals was the highest for the 40 mm electrode distance reactor. In addition, the properties of hydrogen peroxide and ozone were also studied under arc discharge conditions. It was found that the OH radicals were in the ground state and the excited state when a pulsed arc discharge was used. The ozone was produced by the arc discharge even if the oxygen gas is not bubbled into the reactor. The ozone concentration produces a maximum value with treatment time.

  15. Spatial and temporal distributions of toxicity in receiving waters around an oil effluent discharge site

    International Nuclear Information System (INIS)

    Krause, P.R.

    1994-01-01

    Distributions of pollutants from a point source discharge within the water column may vary in both time and space. In this study, they examined the spatial and temporal patterns of toxicity from an oil production effluent (produced water) discharge plume using sea urchin fertilization and development bioassays. Specifically, they tested the sensitivity and response patterns of sea urchin gametes and early life stages exposed to receiving waters sampled along a 1 km transact near an active produced water outfall. Fertilization success and development of larvae to the pluteus stage varied significantly with proximity to the outfall, with reduced fertilization and larval development found closer to the outfall. Although estimated toxicity in receiving water samples, based on fertilization success, was variable in time -- perhaps responding to variation in the quantity or make-up of produced water discharges -- the general spatial pattern of toxicity along the sampling transact remained relatively constant. Strong evidence that field toxicity was directly attributable to produced water effluents was provided by sampling the receiving waters while the produced water discharge was not operating. At such a time, no toxicity was found at any of the field sites. Receiving water toxicity data, along with toxicity data from the effluent itself, were used to prepare a ''map'' of effective effluent concentrations along the sampling transect

  16. A Modified Water-Table Fluctuation Method to Characterize Regional Groundwater Discharge

    Directory of Open Access Journals (Sweden)

    Lihong Yang

    2018-04-01

    Full Text Available A modified Water-Table Fluctuation (WTF method is developed to quantitatively characterize the regional groundwater discharge patterns in stressed aquifers caused by intensive agricultural pumping. Two new parameters are defined to express the secondary information in the observed data. One is infiltration efficiency and the other is discharge modulus (recurring head loss due to aquifer discharge. An optimization procedure is involved to estimate these parameters, based on continuous groundwater head measurements and precipitation records. Using the defined parameters and precipitation time series, water level changes are calculated for individual wells with fidelity. The estimated parameters are then used to further address the characterization of infiltration and to better quantify the discharge at the regional scale. The advantage of this method is that it considers recharge and discharge simultaneously, whereas the general WTF methods mostly focus on recharge. In the case study, the infiltration efficiency reveals that the infiltration is regionally controlled by the intrinsic characteristics of the aquifer, and locally distorted by engineered hydraulic structures that alter surface water-groundwater interactions. The seasonality of groundwater discharge is characterized by the monthly discharge modulus. These results from individual wells are clustered into groups that are consistent with the local land use pattern and cropping structures.

  17. Global River Discharge and Water Temperature under Climate Change

    NARCIS (Netherlands)

    Vliet, van M.T.H.; Franssen, W.H.P.; Yearsley, J.R.; Ludwig, F.; Haddeland, I.; Lettenmaier, D.P.; Kabat, P.

    2013-01-01

    Climate change will affect hydrologic and thermal regimes of rivers, having a direct impact on freshwater ecosystems and human water use. Here we assess the impact of climate change on global river flows and river water temperatures, and identify regions that might become more critical for

  18. 30 CFR 250.217 - What solid and liquid wastes and discharges information and cooling water intake information must...

    Science.gov (United States)

    2010-07-01

    ... What solid and liquid wastes and discharges information and cooling water intake information must accompany the EP? The following solid and liquid wastes and discharges information and cooling water intake... 30 Mineral Resources 2 2010-07-01 2010-07-01 false What solid and liquid wastes and discharges...

  19. Discharge of water containing waste emanating from land to the ...

    African Journals Online (AJOL)

    containing waste (wastewater), which emanates from land-based sources and which directly impact on the marine environment. These sources include sea outfalls, storm water drains, canals, rivers and diffuse sources of pollution. To date ...

  20. 33 CFR 336.1 - Discharges of dredged or fill material into waters of the U.S.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Discharges of dredged or fill material into waters of the U.S. 336.1 Section 336.1 Navigation and Navigable Waters CORPS OF ENGINEERS... ENGINEERS DREDGING PROJECTS INVOLVING THE DISCHARGE OF DREDGED MATERIAL INTO WATERS OF THE U.S. AND OCEAN...

  1. Stability of alternating current discharges between water drops on insulation surfaces

    International Nuclear Information System (INIS)

    Rowland, S M; Lin, F C

    2006-01-01

    Discharges between water drops are important in the ageing of hydrophobic outdoor insulators. They may also be important in the processes leading up to flashover of these insulators in high pollution conditions. This paper considers discharges between drops when a limited alternating current is available, as experienced by an ageing insulator in service. A phenomenon is identified in which the length of a discharge between two drops is reduced through a particular type of distortion of the drops. This is visually characterized as a liquid protrusion from each of a pair of water drops along the insulator surface. This process is distinct from vibration of the drops, general distortion of their shape and the very fast emission of jet streams seen in very high fields. The process depends upon the discharge current, the resistivity of the moisture and the hydrophobicity of the insulation surface

  2. Purification of inkjet ink from water using liquid phase, electric discharge polymerization and cellulosic membrane filtration.

    Science.gov (United States)

    Jordan, Alexander T; Hsieh, Jeffery S; Lee, Daniel T

    2013-01-01

    A method to separate inkjet ink from water was developed using a liquid phase, electric discharge process. The liquid phase, electric discharge process with filtration or sedimentation was shown to remove 97% of inkjet ink from solutions containing between 0.1-0.8 g/L and was consistent over a range of treatment conditions. Additionally, particle size analysis of treated allyl alcohol and treated propanol confirmed the electric discharge treatment has a polymerization mechanism, and small molecule analysis of treated methanol using gas chromatography and mass spectroscopy confirmed the mechanism was free radical initiated polymerization.

  3. Plutonium discharges to the sanitary sewer: Health impacts at the Livermore Water Reclamation Plant

    International Nuclear Information System (INIS)

    Balke, B.K.

    1993-01-01

    The Lawrence Livermore National Laboratory (LLNL) is the largest discharger of sewage treated by the Livermore Water Reclamation (LWRP), contributing approximately 7% by volume of the LWRP influent LILNL operations, as potential sources both of industrial pollutants and radioactivity, are therefore of particular concern to the LWRP. For this reason, LLNL has maintained vigorous wastewater discharge control and monitoring programs. In particular, the monitoring program has demonstrated that, except in a few rare instances, the concentration of contaminants in LLNL effluent have always remained below the appropriate regulatory standards. The exceptions have generally been due to inadvertent discharges of metals-bearing solutions produced by metal plating or cleaning operations

  4. Plasma treatment of polyethylene tubes in continuous regime using surface dielectric barrier discharge with water electrodes

    Science.gov (United States)

    Galmiz, Oleksandr; Zemánek, Miroslav; Pavliňák, David; Černák, Mirko

    2018-05-01

    Combining the surface dielectric barrier discharges generated in contact with water based electrolytes, as the discharge electrodes, we have designed a new type of surface electric discharge, generating thin layers of plasma which propagate along the treated polymer surfaces. The technique was aimed to achieve uniform atmospheric pressure plasma treatment of polymeric tubes and other hollow bodies. The results presented in this work show the possibility of such system to treat outer surface of polymer materials in a continuous mode. The technical details of experimental setup are discussed as well as results of treatment of polyethylene tubes are shown.

  5. Influence Voltage Pulse Electrical Discharge In The Water at the Endurance Fatigue Of Carbon Steel

    OpenAIRE

    I.A. Vakulenko; A.G. Lisnyak

    2016-01-01

    Effect of pulses of electrical discharge in the water at the magnitude of the limited endurance under cyclic loading thermally hardened carbon steel was investigated. Observed increase stamina during cyclic loading a corresponding increase in the number of accumulated dislocations on the fracture surface. Using the equation of Cofino-Manson has revealed a decrease of strain loading cycle after treatment discharges. For field-cycle fatigue as a result of processing the voltage pulses carbon st...

  6. The discharge of radioactive effluents from the nuclear power programme into western waters of Great Britain

    International Nuclear Information System (INIS)

    Allday, C.

    1977-01-01

    A brief account is presented of the British nuclear power programme and the types of radioactive effluent that arise from the power stations and from the Windscale reprocessing plant. Routes by which these effluents could affect human populations, and radiation dose limits which have been laid down, are discussed. The discharge of permitted amounts of activity into western coastal waters of Great Britain, and the requirements for monitoring the discharges, are described. (U.K.)

  7. Luminous phase of nanosecond discharge in deionized water: morphology, propagation velocity and optical emission.

    Czech Academy of Sciences Publication Activity Database

    Šimek, Milan; Pongrác, Branislav; Babický, Václav; Člupek, Martin; Lukeš, Petr

    2017-01-01

    Roč. 26, č. 7 (2017), č. článku 07LT01. ISSN 0963-0252 R&D Projects: GA ČR(CZ) GA15-12987S Institutional support: RVO:61389021 Keywords : water * nanosecond discharge * emission spectra * breakdown Subject RIV: BL - Plasma and Gas Discharge Physics OBOR OECD: Fluids and plasma physics (including surface physics) Impact factor: 3.302, year: 2016 http://iopscience.iop.org/article/10.1088/1361-6595/aa758d

  8. Impact of water and sediment discharges on subaqueous delta evolution in Yangtze Estuary from 1950 to 2010

    Directory of Open Access Journals (Sweden)

    Yun-ping Yang

    2014-07-01

    Full Text Available In order to determine how the subaqueous delta evolution depends on the water and sediment processes in the Yangtze Estuary, the amounts of water and sediment discharged into the estuary were studied. The results show that, during the period from 1950 to 2010, there was no significant change in the annual water discharge, and the multi-annual mean water discharge increased in dry seasons and decreased in flood seasons. However, the annual sediment discharge and the multi-annual mean sediment discharge in flood and dry seasons took on a decreasing trend, and the intra-annual distribution of water and sediment discharges tended to be uniform. The evolution process from deposition to erosion occurred at the −10 m and −20 m isobaths of the subaqueous delta. The enhanced annual water and sediment discharges had a silting-up effect on the delta, and the effect of sediment was greater than that of water. Based on data analysis, empirical curves were built to present the relationships between the water and sediment discharges over a year or in dry and flood seasons and the erosion/deposition rates in typical regions of the subaqueous delta, whose evolution followed the pattern of silting in flood seasons and scouring in dry seasons. Notably, the Three Gorges Dam has changed the distribution processes of water and sediment discharges, and the dam's regulating and reserving functions can benefit the subaqueous delta deposition when the annual water and sediment discharges are not affected.

  9. Use of stream water pH and specific conductance measurements to identify ground water discharges of fly ash leachate

    International Nuclear Information System (INIS)

    Price, R.M.

    1992-01-01

    Low pH and high specific conductance are typical chemical characteristics of coal fly ash leachate. Measurements of these parameters in streams adjacent to a fly ash facility were used to identify areas of ground water discharge into the streams. In-situ specific conductance and pH were determined at approximately 50 surface water stations from on-site and off-site streams. The results of the in-situ determinations were used to select twelve surface water stations for more detailed chemical analyses. The chemical character of the stream water affected by ground water discharges was similar to the water quality of sedimentation ponds which received drainage from the fly ash embankment. The results indicated that in-situ measurements of indicator parameters such as pH and specific conductance can be used as a screening method for identifying surface water quality impacts at fly ash facilities

  10. Modelling mid-span water table depth and drainage discharge ...

    African Journals Online (AJOL)

    2015-04-03

    Apr 3, 2015 ... were monitored in 1.7 m deep piezometers installed mid-way between two drains by using an electronic .... logical components in soils with shallow water tables. ..... dency of neither under-estimating nor over-estimating DDs,.

  11. In-stream Physical Heterogeneity, Rainfall Aided Flushing, and Discharge on Stream Water Quality.

    Science.gov (United States)

    Gomes, Pattiyage I A; Wai, Onyx W H

    2015-08-01

    Implications of instream physical heterogeneity, rainfall-aided flushing, and stream discharge on water quality control have been investigated in a headwater stream of a climatic region that has contrasting dry and wet seasons. Dry (low flow) season's physical heterogeneity showed a positive correlation with good water quality. However, in the wet season, physical heterogeneity showed minor or no significance on water quality variations. Furthermore, physical heterogeneity appeared to be more complementary with good water quality subsequent to rainfall events. In many cases stream discharge was a reason for poor water quality. For the dry season, graywater inputs to the stream could be held responsible. In the wet season, it was probably the result of catchment level disturbances (e.g., regulation of ephemeral freshwater paths). Overall, this study revealed the importance of catchment-based approaches on water quality improvement in tandem with in-stream approaches framed on a temporal scale.

  12. Treatment techniques for the recycling of bottle washing water in the soft drinks industry.

    Science.gov (United States)

    Ramirez Camperos, E; Mijaylova Nacheva, P; Diaz Tapia, E

    2004-01-01

    The soft drink production is an important sector in the manufacturing industry of Mexico. Water is the main source in the production of soft drinks. Wastewater from bottle washing is almost 50% of the total wastewater generated by this industry. In order to reduce the consumption of water, the water of the last bottle rinse can be reused in to the bottle pre-rinse and pre-washing cycles. This work presents the characterization of the final bottle washing rinse discharge and the treatability study for the most appropriate treatment system for recycling. Average characteristics of the final bottle wash rinse were as follows: Turbidity 40.46 NTU, COD 47.7 mg/L, TSS 56 mg/L, TS 693.6 mg/L, electrical conductivity 1,194 microS/cm. The results of the treatability tests showed that the final rinse water can be used in the pre-rinse and pre-washing after removing the totality of the suspended solids, 80% of the COD and 75% of the dissolved solids. This can be done using the following treatment systems: filtration-adsorption-reverse osmosis, or filtration-adsorption-ion exchange. The installation of these treatment techniques in the soft drink industry would decrease bottle washing water consumption by 50%.

  13. Effect of land use change on water discharge in Srepok watershed, Central Highland, Viet Nam

    Directory of Open Access Journals (Sweden)

    Nguyen Thi Ngoc Quyen

    2014-09-01

    Full Text Available Srepok watershed plays an important role in Central Highland in Viet Nam. It impacts to developing social-economic conditions. Therefore, it is necessary to research elements which impact to natural resources in this watershed. The Soil and Water Assessment Tool (SWAT model and Geography Information System (GIS were used to simulate water discharge in the Srepok watershed. The objectives of the research were to apply GIS and SWAT model for simulation water discharge and then, we assessed land use change which impacted on water discharge in the watershed. The observed stream flow data from Ban Don Stream gauge station was used to calibrate for the period from 1981 to 2000 and then validate for the period from 2001 to 2009. After using SWAT-CUP software to calibration, NSI reached 0.63 and R square value achieved 0.64 from 2004 to 2008 in calibration and NSI gained good level at 0.74 and R square got 0.75 from 2009 to 2012 in validation step at Ban Don Station. After that, land cover in 2010 was processed like land cover in 2000 and set up SWAT model again. The simulated water discharge in scenario 1 (land use 2000 was compared with scenario 2 (land use 2010, the simulation result was not significant difference between two scenarios because the change of area of land use was not much enough to affect the fluctuation of water discharge. However, the effect of land cover on water resource could be seen clearly via total water yield. The percentage of surface flow in 2000 was twice times more than in 2010; retard and base flow in 2000 was slightly more than in 2010. Therefore, decreased surface flow, increased infiltration capacity of water and enriched base flow resulted in the growth of land cover.

  14. Plasma processes in water under effect of short duration pulse discharges

    Science.gov (United States)

    Gurbanov, Elchin

    2013-09-01

    It is very important to get a clear water without any impurities and bacteria by methods, that don't change the physical and chemical indicators of water now. In this article the plasma processes during the water treatment by strong electric fields and short duration pulse discharges are considered. The crown discharge around an electrode with a small radius of curvature consists of plasma leader channels with a high conductivity, where the thermo ionization processes and UV-radiation are taken place. Simultaneously the partial discharges around potential electrode lead to formation of atomic oxygen and ozone. The spark discharge arises, when plasma leader channels cross the all interelectrode gap, where the temperature and pressure are strongly grown. As a result the shock waves and dispersing liquid streams in all discharge gap are formed. The plasma channels extend, pressure inside it becomes less than hydrostatic one and the collapse and UV-radiation processes are started. The considered physical processes can be successfully used as a basis for development of pilot-industrial installations for conditioning of drinking water and to disinfecting of sewage.

  15. Synergistic effect of pulsed corona discharges and ozonation on decolourization of methylene blue in water

    CERN Document Server

    Malik, M A; Ghaffar, A; Ahmed, K

    2002-01-01

    The effect of O sub 2 and O sub 3 bubbling on decolourization of methylene blue by pulsed corona discharges in water was studied. The pulsed corona discharges were produced by charging an 80 pF capacitor with a 40 kV DC source, through a 100 M OMEGA resistor, and discharging it into a needle-plate type reactor at 60 Hz through a rotating spark gap switch. A 20 ml sample of 13.25 mg l sup - sup 1 methylene blue in distilled water was decolourized in 120 min. Bubbling O sub 2 at 10 ml min sup - sup 1 through the discharge region reduced the decolourization time to 25 min. Bubbling O sub 2 containing 1500 mu mol O sub 3 l sup - sup 1 at 10 ml min sup - sup 1 reduced the decolourization time to 8 min. The O sub 3 was produced by fractionating input energy between a water treatment reactor and a O sub 3 generator, i.e. no additional energy was consumed for O sub 3 production. Under the same experimental conditions methylene blue solution in tap water was decolourized in >210 min by corona discharge in solution, in...

  16. A determination of discharge head of the Cherepnov water lifter with siphon

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Kwan Soo; Rhee, Kyoung Hoon [Chonnam National Univ., Kwangju (Korea, Republic of); Park, Sung Chun [Dongshin University, Naju (Korea, Republic of); Jeong, Byoung Kyen [Sunchon Technical Junior College, Sunchon (Korea, Republic of)

    1996-02-29

    This paper presents an experimental study on the discharge head of Cherepnov water lifter that was continuously operated with the aid of the siphon. The energy used by the Cherepnov water lifter is derived from the potential energy of the water itself. The lifter consists of three interconnected tanks and five pipes, one of which is open and two others are hermetically sealed. The effects of varying operating parameters such as the tank and pipe size, the ratio between head of discharge and drop height were analyzed. As a result, factors that can maximize the efficiency and increase the average delivery rate were identified. When the ratio between head of discharge and drop height is about 0.5, the efficiency of Cherepnov water lifter is maximized. In order to design the efficient Cherepnov water lifter, the discharge head of the Cherepnov water lifter should be assigned to be twice as much as the drop height. The effect of tank size on the efficiency is less than 5%, while the effect of the pipe size is not negligible. The larger the pipe size is, the more the efficiency increases. (author). 13 refs., 4 tabs., 8 figs.

  17. Indexes of contamination for characterization of continental waters and discharges. Formulations

    International Nuclear Information System (INIS)

    Ramirez, Restrepo R; Cardenosa, M

    1999-01-01

    Contamination indexes (ICO) for characterization of natural water bodies and industrial discharges have been formulated in previous works by Ramirez, et al, 1997 in this work, complementary indexes not correlated with other ICOS previously developed are established thus resulting in a complementary tool to be applied in the interpretation and characterization on continental surface water bodies. First, a pH index (ICOpH) is obtained to determine ph incidence on water quality interpretation. A temperature index (ICOTEM) is also obtained to evaluate effluent incidence on receiving water bodies. ICOTEM is based on temperature difference of the wastewater discharge and the water body. Finally, indexes for the evaluation of aromatic and aliphatic hydrocarbons are also developed based on data collected on sediments and fish tissue samples. These hydrocarbon compounds are highly viable to accumulate and produce long-term detrimental effects on living organisms. These latter indexes have been developed based on data of nearly 130 samples collected during monitoring campaigns in streams and water bodies affected by discharges of the petroleum industry or by accidental spills of crude oil or hydrocarbon by-products in Colombian streams; its also possible that anthropic influence other than petroleum discharges might be affecting the streams included in the monitoring campaigns

  18. Critical discharge of initially subcooled water through slits

    International Nuclear Information System (INIS)

    Amos, C.N.; Schrock, V.E.

    1983-09-01

    This report describes an experimental investigation into the critical flow of initially subcooled water through rectangular slits. The study of such flows is relevant to the prediction of leak flow rates from cracks in piping, or pressure vessels, which contain sufficient enthalpy that vaporization will occur if they are allowed to expand to the ambient pressure. Two new analytical models, which allow for the generation of a metastable liquid phase, are developed. Experimental results are compared with the predictions of both these new models and with a Fanno Homogeneous Equilibrium Model

  19. Critical discharge of initially subcooled water through slits. [PWR; BWR

    Energy Technology Data Exchange (ETDEWEB)

    Amos, C N; Schrock, V E

    1983-09-01

    This report describes an experimental investigation into the critical flow of initially subcooled water through rectangular slits. The study of such flows is relevant to the prediction of leak flow rates from cracks in piping, or pressure vessels, which contain sufficient enthalpy that vaporization will occur if they are allowed to expand to the ambient pressure. Two new analytical models, which allow for the generation of a metastable liquid phase, are developed. Experimental results are compared with the predictions of both these new models and with a Fanno Homogeneous Equilibrium Model.

  20. Fluoride varnish or fluoride mouth rinse?

    DEFF Research Database (Denmark)

    Keller, M K; Klausen, BJ; Twetman, S

    2016-01-01

    OBJECTIVE: In many Danish communities, school-based fluoride programs are offered to children with high caries risk in adjunct to tooth brushing. The purpose of this field trial was to compare the caries-preventive effectiveness of two different fluoride programs in 6-12 year olds. BASIC RESEARCH...... different schools were enrolled after informed consent and their class unit was randomly allocated to one of two fluoride programs. INTERVENTIONS: One group received a semi-annual fluoride varnish applications (FV) and the other group continued with an existing program with fluoride mouth rinses once per...... in caries development over two years among children participating in a school-based fluoride varnish or mouth rinse program....

  1. Nanosecond Discharge in Bubbled Liquid n-Heptane: Effects of Gas Composition and Water Addition

    KAUST Repository

    Hamdan, Ahmad

    2016-08-30

    Recently, an aqueous discharge reactor was developed to facilitate reformation of liquid fuels by in-liquid plasma. To gain a microscopic understanding of the physical elements behind this aqueous reactor, we investigate nanosecond discharges in liquid n-heptane with single and double gaseous bubbles in the gap between electrodes. We introduce discharge probability (DP) to characterize the stochastic nature of the discharges, and we investigate the dependence of DP on the gap distance, applied voltage, gaseous bubble composition, and the water content in n-heptane/distilled-water emulsified mixtures. Propagation of a streamer through the bubbles indicates no discharges in the liquids. DP is controlled by the properties of the gaseous bubble rather than by the composition of the liquid mixture in the gap with a single bubble; meanwhile, DP is determined by the dielectric permittivity of the liquid mixture in the gap with double bubbles, results that are supported by static electric field simulations. We found that a physical mechanism of increasing DP is caused by an interaction between bubbles and an importance of the dielectric permittivity of a liquid mixture on the local enhancement of field intensity. We also discuss detailed physical characteristics, such as plasma lifetime and electron density within the discharge channel, by estimating from measured emissions with a gated-intensified charge-coupled device and by using spectroscopic images, respectively. © 1973-2012 IEEE.

  2. Environmental effects of large discharges of cooling water. Experiences from Swedish nuclear power plants

    International Nuclear Information System (INIS)

    Ehlin, Ulf; Lindahl, Sture; Neuman, Erik; Sandstroem, Olof; Svensson, Jonny

    2009-07-01

    Monitoring the environmental effects of cooling water intake and discharge from Swedish nuclear power stations started at the beginning of the 1960s and continues to this day. In parallel with long-term monitoring, research has provided new knowledge and methods to optimise possible discharge locations and design, and given the ability to forecast their environmental effects. Investigations into the environmental effects of cooling-water are a prerequisite for the issuing of power station operating permits by the environmental authorities. Research projects have been carried out by scientists at universities, while the Swedish Environmental Protection Agency, the Swedish Board of Fisheries, and the Swedish Meteorological and Hydrological Institute, SMHI, are responsible for the greater part of the investigations as well as of the research work. The four nuclear power plants dealt with in this report are Oskarshamn, Ringhals, Barsebaeck and Forsmark. They were taken into operation in 1972, 1975, 1975 and 1980 resp. - a total of 12 reactors. After the closure of the Barsebaeck plants in 2005, ten reactors remain in service. The maximum cooling water discharge from the respective stations was 115, 165, 50 and 135 m 3 /s, which is comparable to the mean flow of an average Swedish river - c:a 150 m 3 /s. The report summarizes studies into the consequences of cooling water intake and discharge. Radiological investigations made at the plants are not covered by this review. The strategy for the investigations was elaborated already at the beginning of the 1960s. The investigations were divided into pre-studies, baseline investigations and monitoring of effects. Pre-studies were partly to gather information for the technical planning and design of cooling water intake and outlet constructions, and partly to survey the hydrographic and ecological situation in the area. Baseline investigations were to carefully map the hydrography and ecology in the area and their natural

  3. The constructional design of cooling water discharge structures on German rivers

    International Nuclear Information System (INIS)

    Geldner, P.; Zimmermann, C.

    1975-11-01

    The present compilation of structures for discharging cooling water from power stations into rivers is an attempt to make evident developments in the constructional design of such structures and to give reasons for special structure shapes. A complete collection of all structures built in Germany, however, is difficult to realize because of the large number of power stations. For conventionally heated power stations therefore only a selection was made, while nuclear power stations in operation or under construction could almost completely be taken into account. For want of sufficient quantities of water for river water cooling, projected power stations are now almost exclusively designed for closed-circuit cooling so that the required discharge structures for elutrition water from the cooling towers as well as for the emergency and secondary cooling circuits have to be designed only for small amounts of water. (orig./HP) [de

  4. Effects of air temperature and discharge on Upper Mississippi River summer water temperatures

    Science.gov (United States)

    Gray, Brian R.; Robertson, Dale M.; Rogala, James T.

    2018-01-01

    Recent interest in the potential effects of climate change has prompted studies of air temperature and precipitation associations with water temperatures in rivers and streams. We examined associations between summer surface water temperatures and both air temperature and discharge for 5 reaches of the Upper Mississippi River during 1994–2011. Water–air temperature associations at a given reach approximated 1:1 when estimated under an assumption of reach independence but declined to approximately 1:2 when water temperatures were permitted to covary among reaches and were also adjusted for upstream air temperatures. Estimated water temperature–discharge associations were weak. An apparently novel feature of this study is that of addressing changes in associations between water and air temperatures when both are correlated among reaches.

  5. Pin Hole Discharge Creation in Na2SO4 Water Solutions

    Directory of Open Access Journals (Sweden)

    Lucie Hlavatá

    2013-01-01

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

  6. Characterization of a dielectric barrier discharge in contact with liquid and producing a plasma activated water

    Science.gov (United States)

    Neretti, G.; Taglioli, M.; Colonna, G.; Borghi, C. A.

    2017-01-01

    In this work a low-temperature plasma source for the generation of plasma activated water (PAW) is developed and characterized. The plasma reactor was operated by means of an atmospheric-pressure air dielectric barrier discharge (DBD). The plasma generated is in contact with the water surface and is able to chemically activate the liquid medium. Electrodes were supplied by both sinusoidal and nanosecond-pulsed voltage waveforms. Treatment times were varied from 2 to 12 min to increase the energy dose released to the water by the DBD plasma. The physics of the discharge was studied by means of electrical, spectroscopic and imaging diagnostics. The interaction between the plasma and the liquid was investigated as well. Temperature and composition of the treated water were detected. Images of the discharges showed a filamentary behaviour in the sinusoidal case and a more homogeneous behaviour in the nanosecond-pulsed one. The images and the electrical measurements allowed to evaluate an average electron number density of about 4  ×  1019 and 6  ×  1017 m-3 for the sinusoidal and nanosecond-pulsed discharges respectively. Electron temperatures in the range of 2.1÷2.6 eV were measured by using spectroscopic diagnostics. Rotational temperatures in the range of 318-475 K were estimated by fitting synthetic spectra with the measured ones. Water temperature and pH level did not change significantly after the exposure to the DBD plasma. The production of ozone and hydrogen peroxide within the water was enhanced by increasing the plasma treatment time and the energy dose. Numerical simulations of the nanosecond-pulsed discharge were performed by using a self-consistent coupling of state-to-state kinetics of the air mixture with the Boltzmann equation of free electron kinetics. Temporal evolution of the electron energy distribution function shows departure from the Maxwellian distribution especially during the afterglow phase of the discharge. When

  7. Discrete simulations of spatio-temporal dynamics of small water bodies under varied stream flow discharges

    Science.gov (United States)

    Daya Sagar, B. S.

    2005-01-01

    Spatio-temporal patterns of small water bodies (SWBs) under the influence of temporally varied stream flow discharge are simulated in discrete space by employing geomorphologically realistic expansion and contraction transformations. Cascades of expansion-contraction are systematically performed by synchronizing them with stream flow discharge simulated via the logistic map. Templates with definite characteristic information are defined from stream flow discharge pattern as the basis to model the spatio-temporal organization of randomly situated surface water bodies of various sizes and shapes. These spatio-temporal patterns under varied parameters (λs) controlling stream flow discharge patterns are characterized by estimating their fractal dimensions. At various λs, nonlinear control parameters, we show the union of boundaries of water bodies that traverse the water body and non-water body spaces as geomorphic attractors. The computed fractal dimensions of these attractors are 1.58, 1.53, 1.78, 1.76, 1.84, and 1.90, respectively, at λs of 1, 2, 3, 3.46, 3.57, and 3.99. These values are in line with general visual observations.

  8. Discrete simulations of spatio-temporal dynamics of small water bodies under varied stream flow discharges

    Directory of Open Access Journals (Sweden)

    B. S. Daya Sagar

    2005-01-01

    Full Text Available Spatio-temporal patterns of small water bodies (SWBs under the influence of temporally varied stream flow discharge are simulated in discrete space by employing geomorphologically realistic expansion and contraction transformations. Cascades of expansion-contraction are systematically performed by synchronizing them with stream flow discharge simulated via the logistic map. Templates with definite characteristic information are defined from stream flow discharge pattern as the basis to model the spatio-temporal organization of randomly situated surface water bodies of various sizes and shapes. These spatio-temporal patterns under varied parameters (λs controlling stream flow discharge patterns are characterized by estimating their fractal dimensions. At various λs, nonlinear control parameters, we show the union of boundaries of water bodies that traverse the water body and non-water body spaces as geomorphic attractors. The computed fractal dimensions of these attractors are 1.58, 1.53, 1.78, 1.76, 1.84, and 1.90, respectively, at λs of 1, 2, 3, 3.46, 3.57, and 3.99. These values are in line with general visual observations.

  9. Characteristics of meter-scale surface electrical discharge propagating along water surface at atmospheric pressure

    International Nuclear Information System (INIS)

    Hoffer, Petr; Sugiyama, Yuki; Hosseini, S Hamid R; Akiyama, Hidenori; Lukes, Petr; Akiyama, Masahiro

    2016-01-01

    This paper reports physical characteristics of water surface discharges. Discharges were produced by metal needle-to-water surface geometry, with the needle electrode driven by 47 kV (FWHM) positive voltage pulses of 2 µ s duration. Propagation of discharges along the water surface was confined between glass plates with 2 mm separation. This allowed generation of highly reproducible 634 mm-long plasma filaments. Experiments were performed using different atmospheres: air, N 2 , and O 2 , each at atmospheric pressure. Time- and spatially-resolved spectroscopic measurements revealed that early spectra of discharges in air and nitrogen atmospheres were dominated by N 2 2nd positive system. N 2 radiation disappeared after approx. 150 ns, replaced by emissions from atomic hydrogen. Spectra of discharges in O 2 atmosphere were dominated by emissions from atomic oxygen. Time- and spatially-resolved emission spectra were used to determine temperatures in plasma. Atomic hydrogen emissions showed excitation temperature of discharges in air to be about 2  ×  10 4 K. Electron number densities determined by Stark broadening of the hydrogen H β line reached a maximum value of ∼10 18 cm −3 just after plasma initiation. Electron number densities and temperatures depended only slightly on distance from needle electrode, indicating formation of high conductivity leader channels. Direct observation of discharges by high speed camera showed that the average leader head propagation speed was 412 km · s −1 , which is substantially higher value than that observed in experiments with shorter streamers driven by lower voltages. (paper)

  10. A national approach to the regulation of water discharge from uranium mines

    International Nuclear Information System (INIS)

    Willis, J.L.

    1985-09-01

    This paper is concerned with outlining the development of a national approach to the regulation of water discharge from uranium mines in Australia. The history of the Australian uranium industry is briefly sketched to illustrate the changes that have taken place in environmental management, and more particularly water management, over this period. The main focus of the paper is on the requirements relating to the establishment of effluent discharge limits contained in the Code of Practice on the Management of Radioactive Wastes from the Mining and Milling of Radioactive Ores, 1982. The code adopts a site specific approach to the formulation of discharge limits rather than providing generic recommendations. This approach requires the application of a rigorous and disciplined methodology

  11. Ecosystem under pressure: ballast water discharge into Galveston Bay, Texas (USA) from 2005 to 2010.

    Science.gov (United States)

    Steichen, Jamie L; Windham, Rachel; Brinkmeyer, Robin; Quigg, Antonietta

    2012-04-01

    Ballast water exchange processes facilitate the dispersal and unnatural geographic expansion of phytoplankton, including harmful algal bloom species. From 2005 to 2010, over 45,000 vessels (≈ 8000 annually) travelled across Galveston Bay (Texas, USA) to the deep-water ports of Houston (10th largest in the world), Texas City and Galveston. These vessels (primarily tankers and bulkers) discharged ≈ 1.2 × 10(8) metrictons of ballast water; equivalent to ≈ 3.4% of the total volume of the Bay. Over half of the ballast water discharged had a coastwise origin, 96% being from US waters. Galveston Bay has fewer non-indigenous species but receives a higher volume of ballast water discharge, relative to the highly invaded Chesapeake and San Francisco Bays. Given the magnitude of shipping traffic, the role of Galveston Bay, both as a recipient and donor region of non-indigenous phytoplankton species is discussed here in terms of the invasibility risk to this system by way of ballast water. Copyright © 2012 Elsevier Ltd. All rights reserved.

  12. The source, discharge, and chemical characteristics of water from Agua Caliente Spring, Palm Springs, California

    Science.gov (United States)

    Contributors: Brandt, Justin; Catchings, Rufus D.; Christensen, Allen H.; Flint, Alan L.; Gandhok, Gini; Goldman, Mark R.; Halford, Keith J.; Langenheim, V.E.; Martin, Peter; Rymer, Michael J.; Schroeder, Roy A.; Smith, Gregory A.; Sneed, Michelle; Martin, Peter

    2011-01-01

    Agua Caliente Spring, in downtown Palm Springs, California, has been used for recreation and medicinal therapy for hundreds of years and currently (2008) is the source of hot water for the Spa Resort owned by the Agua Caliente Band of the Cahuilla Indians. The Agua Caliente Spring is located about 1,500 feet east of the eastern front of the San Jacinto Mountains on the southeast-sloping alluvial plain of the Coachella Valley. The objectives of this study were to (1) define the geologic structure associated with the Agua Caliente Spring; (2) define the source(s), and possibly the age(s), of water discharged by the spring; (3) ascertain the seasonal and longer-term variability of the natural discharge, water temperature, and chemical characteristics of the spring water; (4) evaluate whether water-level declines in the regional aquifer will influence the temperature of the spring discharge; and, (5) estimate the quantity of spring water that leaks out of the water-collector tank at the spring orifice.

  13. The use of lithium as a marker for the retention of liquids in the oral cavity after rinsing.

    Science.gov (United States)

    Hanning, Sara M; Kieser, Jules A; Ferguson, Martin M; Reid, Malcolm; Medlicott, Natalie J

    2014-01-01

    The aim of this study was to validate the use of lithium as a marker to indicate the retention of simple liquids in the oral cavity and use this to determine how much liquid is retained in the oral cavity following 30 s of rinsing. This is a validation study in which saliva was spiked with known concentrations of lithium. Twenty healthy participants then rinsed their mouths with either water or a 1 % w/v carboxymethylcellulose (CMC) solution for 30 s before expectorating into a collection cup. Total volume and concentration of lithium in the expectorant were then measured, and the percentage of liquid retained was calculated. The mean amount of liquid retained was 10.4 ± 4.7 % following rinsing with water and 15.3 ± 4.1 % following rinsing with 1 % w/v CMC solution. This difference was significant (p < 0.01). Lithium was useful as a marker for the retention of liquids in the oral cavity, and a value for the amount of water and 1 % w/v CMC solution remaining in the oral cavity following a 30-s rinse was established. The present study quantifies the retention of simple fluids in the oral cavity, validating a technique that may be applied to more complex fluids such as mouth rinses. Further, the application of this method to specific population groups such as those with severe xerostomia may assist in developing effective saliva substitutes.

  14. A Simulation of Pre-Arcing Plasma Discharge Processes in Water Purification

    International Nuclear Information System (INIS)

    Rodriguez-Mendez, B. G.; Piedad-Beneitez, A. de la; Lopez-Callejas, R.; Godoy-Cabrera, O. G.; Benitez-Read, J. S.; Pacheco-Sotelo, J. O.; Pena-Eguiluz, R.; Mercado-Cabrera, A.; Valencia-A, R.; Barocio, S. R.

    2006-01-01

    The simulation of a water purification system within a coaxial cylinder reactor operated by 1 kHz frequency plasma discharges in pre-arcing regimes is presented. In contrast with precedent works, this computational model considers three mechanisms of the system operation: (a) the relevant physical characteristics of water (b) the ionisation and expansion processes in the spark channel including the near-breakdown electric current generated by the rate of change of the effective capacitance and resistance in the discharge, and (c) the energy associated with this initial spark in the water. The outcome of the model seems to meet all main requirements to allow the design and construction of specific water purification technology devices

  15. Permitted water pollution discharges and population cancer and non-cancer mortality: toxicity weights and upstream discharge effects in US rural-urban areas.

    Science.gov (United States)

    Hendryx, Michael; Conley, Jamison; Fedorko, Evan; Luo, Juhua; Armistead, Matthew

    2012-04-02

    The study conducts statistical and spatial analyses to investigate amounts and types of permitted surface water pollution discharges in relation to population mortality rates for cancer and non-cancer causes nationwide and by urban-rural setting. Data from the Environmental Protection Agency's (EPA) Discharge Monitoring Report (DMR) were used to measure the location, type, and quantity of a selected set of 38 discharge chemicals for 10,395 facilities across the contiguous US. Exposures were refined by weighting amounts of chemical discharges by their estimated toxicity to human health, and by estimating the discharges that occur not only in a local county, but area-weighted discharges occurring upstream in the same watershed. Centers for Disease Control and Prevention (CDC) mortality files were used to measure age-adjusted population mortality rates for cancer, kidney disease, and total non-cancer causes. Analysis included multiple linear regressions to adjust for population health risk covariates. Spatial analyses were conducted by applying geographically weighted regression to examine the geographic relationships between releases and mortality. Greater non-carcinogenic chemical discharge quantities were associated with significantly higher non-cancer mortality rates, regardless of toxicity weighting or upstream discharge weighting. Cancer mortality was higher in association with carcinogenic discharges only after applying toxicity weights. Kidney disease mortality was related to higher non-carcinogenic discharges only when both applying toxicity weights and including upstream discharges. Effects for kidney mortality and total non-cancer mortality were stronger in rural areas than urban areas. Spatial results show correlations between non-carcinogenic discharges and cancer mortality for much of the contiguous United States, suggesting that chemicals not currently recognized as carcinogens may contribute to cancer mortality risk. The geographically weighted

  16. Permitted water pollution discharges and population cancer and non-cancer mortality: toxicity weights and upstream discharge effects in US rural-urban areas

    Directory of Open Access Journals (Sweden)

    Hendryx Michael

    2012-04-01

    Full Text Available Abstract Background The study conducts statistical and spatial analyses to investigate amounts and types of permitted surface water pollution discharges in relation to population mortality rates for cancer and non-cancer causes nationwide and by urban-rural setting. Data from the Environmental Protection Agency's (EPA Discharge Monitoring Report (DMR were used to measure the location, type, and quantity of a selected set of 38 discharge chemicals for 10,395 facilities across the contiguous US. Exposures were refined by weighting amounts of chemical discharges by their estimated toxicity to human health, and by estimating the discharges that occur not only in a local county, but area-weighted discharges occurring upstream in the same watershed. Centers for Disease Control and Prevention (CDC mortality files were used to measure age-adjusted population mortality rates for cancer, kidney disease, and total non-cancer causes. Analysis included multiple linear regressions to adjust for population health risk covariates. Spatial analyses were conducted by applying geographically weighted regression to examine the geographic relationships between releases and mortality. Results Greater non-carcinogenic chemical discharge quantities were associated with significantly higher non-cancer mortality rates, regardless of toxicity weighting or upstream discharge weighting. Cancer mortality was higher in association with carcinogenic discharges only after applying toxicity weights. Kidney disease mortality was related to higher non-carcinogenic discharges only when both applying toxicity weights and including upstream discharges. Effects for kidney mortality and total non-cancer mortality were stronger in rural areas than urban areas. Spatial results show correlations between non-carcinogenic discharges and cancer mortality for much of the contiguous United States, suggesting that chemicals not currently recognized as carcinogens may contribute to cancer

  17. 76 FR 43230 - National Pollutant Discharge Elimination System-Cooling Water Intake Structures at Existing...

    Science.gov (United States)

    2011-07-20

    ... ENVIRONMENTAL PROTECTION AGENCY 40 CFR Parts 122 and 125 [EPA-HQ-OW-2008-0667, FRL-9441-8] RIN 2040-AE95 National Pollutant Discharge Elimination System--Cooling Water Intake Structures at Existing Facilities and Phase I Facilities AGENCY: Environmental Protection Agency (EPA). ACTION: Proposed rule...

  18. Power Plant Bromide Discharges and Downstream Drinking Water Systems in Pennsylvania.

    Science.gov (United States)

    Good, Kelly D; VanBriesen, Jeanne M

    2017-10-17

    Coal-fired power plants equipped with wet flue gas desulfurization (FGD) systems have been implicated in increasing bromide levels and subsequent increases in disinfection byproducts at downstream drinking water plants. Bromide was not included as a regulated constituent in the recent steam electric effluent limitations guidelines and standards (ELGs) since the U.S. EPA analysis suggested few drinking water facilities would be affected by bromide discharges from power plants. The present analysis uses a watershed approach to identify Pennsylvania drinking water intakes downstream of wet FGD discharges and to assess the potential for bromide discharge effects. Twenty-two (22) public drinking water systems serving 2.5 million people were identified as being downstream of at least one wet FGD discharge. During mean August conditions (generally low-flow, minimal dilution) in receiving rivers, the median predicted bromide concentrations contributed by wet FGD at Pennsylvania intake locations ranged from 5.2 to 62 μg/L for the Base scenario (including only natural bromide in coal) and from 16 to 190 μg/L for the Bromide Addition scenario (natural plus added bromide for mercury control); ranges depend on bromide loads and receiving stream dilution capacity.

  19. Proposal of computation chart for general use for diffusion prediction of discharged warm water

    International Nuclear Information System (INIS)

    Wada, Akira; Kadoyu, Masatake

    1976-01-01

    The authors have developed the unique simulation analysis method using the numerical models for the prediction of discharged warm water diffusion. At the present stage, the method is adopted for the precise analysis computation in order to make the prediction of the diffusion of discharged warm water at each survey point, but instead of this method, it is strongly requested that some simple and easy prediction methods should be established. For the purpose of meeting this demand, in this report, the computation chart for general use is given to predict simply the diffusion range of discharged warm water, after classifying the semi-infinite sea region into several flow patterns according to the sea conditions and conducting the systematic simulation analysis with the numerical model of each pattern, respectively. (1) Establishment of the computation conditions: The special sea region was picked up as the area to be investigated, which is semi-infinite facing the outer sea and along the rectilineal coast line from many sea regions surrounding Japan, and from the viewpoint of the flow and the diffusion characteristics, the sea region was classified into three patterns. 51 cases in total various parameters were obtained, and finally the simulation analysis was performed. (2) Drawing up the general use chart: 28 sheets of the computation chart for general use were drawn, which are available for computing the approximate temperature rise caused by the discharged warm water diffusion. The example of Anegasaki Thermal Power Station is given. (Kako, I.)

  20. Anode pattern formation in atmospheric pressure air glow discharges with water anode

    NARCIS (Netherlands)

    Verreycken, T.; Bruggeman, P.J.; Leys, C.

    2009-01-01

    Pattern formation in the anode layer at a water electrode in atmospheric pressure glow discharges in air is studied. With increasing current a sequence of different anode spot structures occurs from a constricted homogeneous spot in the case of small currents to a pattern consisting of small

  1. Review of the methods to form hydrogen peroxide in electrical discharge plasma with liquid water

    Science.gov (United States)

    Locke, Bruce R.; Shih, Kai-Yuan

    2011-06-01

    This paper presents a review of the literature dealing with the formation of hydrogen peroxide from plasma processes. Energy yields for hydrogen peroxide generation by plasma from water span approximately three orders of magnitude from 4 × 10-2 to 80 g kWh-1. A wide range of plasma processes from rf to pulsed, ac, and dc discharges directly in the liquid phase have similar energy yields and may thus be limited by radical quenching processes at the plasma-liquid interface. Reactor modification using discharges in bubbles and discharges over the liquid phase can provide modest improvements in energy yield over direct discharge in the liquid, but the interpretation is complicated by additional chemical reactions of gas phase components such as ozone and nitrogen oxides. The highest efficiency plasma process utilizes liquid water droplets that may enhance efficiency by sequestering hydrogen peroxide in the liquid and by suppressing decomposition reactions by radicals from the gas and at the interface. Kinetic simulations of water vapor reported in the literature suggest that plasma generation of hydrogen peroxide should approach 45% of the thermodynamics limit, and this fact coupled with experimental studies demonstrating improvements with the presence of the condensed liquid phase suggest that further improvements in energy yield may be possible. Plasma generation of hydrogen peroxide directly from water compares favorably with a number of other methods including electron beam, ultrasound, electrochemical and photochemical methods, and other chemical processes.

  2. Review of the methods to form hydrogen peroxide in electrical discharge plasma with liquid water

    Energy Technology Data Exchange (ETDEWEB)

    Locke, Bruce R; Shih, Kai-Yuan [Department of Chemical and Biomedical Engineering, Florida State University, Tallahassee, FL 32310 (United States)

    2011-06-15

    This paper presents a review of the literature dealing with the formation of hydrogen peroxide from plasma processes. Energy yields for hydrogen peroxide generation by plasma from water span approximately three orders of magnitude from 4 x 10{sup -2} to 80 g kWh{sup -1}. A wide range of plasma processes from rf to pulsed, ac, and dc discharges directly in the liquid phase have similar energy yields and may thus be limited by radical quenching processes at the plasma-liquid interface. Reactor modification using discharges in bubbles and discharges over the liquid phase can provide modest improvements in energy yield over direct discharge in the liquid, but the interpretation is complicated by additional chemical reactions of gas phase components such as ozone and nitrogen oxides. The highest efficiency plasma process utilizes liquid water droplets that may enhance efficiency by sequestering hydrogen peroxide in the liquid and by suppressing decomposition reactions by radicals from the gas and at the interface. Kinetic simulations of water vapor reported in the literature suggest that plasma generation of hydrogen peroxide should approach 45% of the thermodynamics limit, and this fact coupled with experimental studies demonstrating improvements with the presence of the condensed liquid phase suggest that further improvements in energy yield may be possible. Plasma generation of hydrogen peroxide directly from water compares favorably with a number of other methods including electron beam, ultrasound, electrochemical and photochemical methods, and other chemical processes.

  3. Flow Alteration and Chemical Reduction: Air Stripping to Lessen Subsurface Discharges of Mercury to Surface Water

    Science.gov (United States)

    Brooks, S. C.; Bogle, M.; Liang, L.; Miller, C. L.; Peterson, M.; Southworth, G. R.; Spalding, B. P.

    2009-12-01

    Mercury concentrations in groundwater, surface water, and biota near an industrial facility in Oak Ridge, Tennessee remain high some 50 years after the original major releases from the facility to the environment. Since the mid-1980s, various remedial and abatement actions have been implemented at the facility, including re-routing water flows, armoring contaminated stream banks, relining or cleanout of facility storm drains, and activated charcoal treatment of groundwater and sump discharges. These actions were taken to reduce inorganic mercury inputs from the facility to the stream; a strategy that assumes limiting the inorganic mercury precursor will reduce Hg methylation and its subsequent bioaccumulation. To date, such actions have reduced mercury loading from the site by approximately 90% from levels typical of the mid 1980's, but waterborne mercury at the facility boundary remains roughly 100 times the typical local background concentration and methylmercury accumulation in aquatic biota exceed standards for safe consumption by humans and wildlife. In 2008 and 2009, a series of investigations was initiated to explore innovative approaches to further control mercury concentrations in stream water. Efforts in this study focused on decreasing waterborne inorganic mercury inputs from two sources. The first, a highly localized source, is the discharge point of the enclosed stormdrain network whereas the second is a more diffuse short reach of stream where metallic Hg in streambed sediments generates a continued input of dissolved Hg to the overlying water. Moving a clean water flow management discharge point to a position downstream of the contaminated reach reduced mercury loading from the streambed source by 75% - 100%, likely by minimizing resuspension of Hg-rich fine particulates and changing characteristic hyporheic flow path length and residence time. Mercury in the stormdrain discharge exists as highly reactive dissolved Hg(II) due to residual chlorine in

  4. Simulation of chlorinated water discharges from power plants on estuaries and rivers

    International Nuclear Information System (INIS)

    Eraslan, A.H.; Lietzke, M.H.; Fischer, S.K.; Kalmaz, E.V.

    1977-01-01

    The fast-transient (tidal-transient) one-dimensional discrete-element chemical transport model and its associated computer code CHMONE were applied to study the effects of chlorinated water discharges from power plants on tidal estuaries and controlled rivers. The mathematical model has the capability to predict simultaneously the hydrodynamic, thermal, and chemical composition of water as one-dimensional time-dependent distributions

  5. Investigation of electric discharge treatment of water for ammonium nitrogen removal

    International Nuclear Information System (INIS)

    Nazarenko, O.B.; Shubin, B.G.

    2007-01-01

    The possibility of water purification from ammonium nitrogen using pulsed electric discharge in water-air mixtures was investigated. The model solution of chlorous ammonium was used in experiments. The concentration of ions ammonium was about 300 mg/l. Achieved reduction of ammonium concentration was about 35%. In this paper the mechanism of this process is discussed. The ways to increasing efficiency of this method are proposed

  6. Low-dielectric layer increases nanosecond electric discharges in distilled water

    KAUST Repository

    Hamdan, Ahmad

    2016-10-24

    Electric discharge in liquids is an emerging field of research, and is involved into various environmental applications (water purification, fuel reforming, nanomaterial synthesis, etc.). Increasing the treatment efficiency with simultaneous decreasing of the energy consumption are the main goals of today’s research. Here we present an experimental study of nanosecond discharge in distilled water covered by a layer of dielectric material. We demonstrate through this paper that the discharge efficiency can be improved by changing the interface position regarding the anode tip. The efficiency increase is due to the increase of the discharge probability as well as the plasma volume. The understanding of the experimental results is brought and strengthened by simulating the electric field distribution, using Comsol Multiphysics software. Because the dielectric permittivity (ε) is discontinuous at the interface, the electric field is enhanced by a factor that depends on the relative value of ε of the two liquids. The present result is very promising in future: opportunities for potential applications as well as fundamental studies for discharges in liquid.

  7. Notice of intent to discharge water contaminants. Waste Isolation Pilot Plant, Eddy County, NM

    International Nuclear Information System (INIS)

    Hart, J.S.; Porter, K.R.; Register, J.K.

    1983-04-01

    This report provides information in support of a ''Notice of Intent to Discharge Water Contaminants,'' pursuant to Section 1-201 of the New Mexico Water Quality Control Commission Regulations. The anticipated discharges are not expected to move directly or indirectly into groundwater. These discharges will be caused by activities related to the construction of the Waste Isolation Pilot Plant (WIPP), a US Department of Energy (DOE) research and development program to demonstrate the safe disposal of radioactive wastes resulting from defense activities and programs of the United States. The facility is to be developed in deep layers of bedded salt. The WIPP site is located in Eddy County, New Mexico, about 26 miles east of Carlsbad. The US Department of Energy, WIPP Project Office, Albuquerque, New Mexico, as the sponsor of the project, is responsible for any discharges from the site. The following sections describe generally the WIPP construction activities. Pertinent site conditions, potential sources of discharges and their expected effects, and proposed groundwater monitoring efforts are also described

  8. Petroleum-related contaminants near a produced water discharge site in the Santa Barbara Channel

    International Nuclear Information System (INIS)

    Jones, A.D.; Witter, A.E.; Higashi, R.M.

    1994-01-01

    Offshore oil production generates substantial quantities of waste water that is frequently discharged into marine waters. Contamination of coastal sediments occurs due to other inputs including natural petroleum seeps, and this complicates assessments of the environmental effects of produced water in marine ecosystems. The current study has focused on characterization of contaminants in sediments near produced water discharge site off the coast of Southern California. First, it was important to address the question: ''What contaminants in sediments should be monitored as indicators of produced water effects?'' Dichloromethane extracts of sediments were analyzed for numerous organic constituents using gas chromatography-mass spectrometry and selected ion monitoring. Though the phenols and fatty acids were not detected in sediment extracts, normal and branched alkanes and other petroleum hydrocarbon biomarkers were quantified. No relationship was evident that related absolute concentrations of organic compounds to distance from the outfall, but patterns of petroleum hydrocarbons exhibited consistent spatial variations that could be related to distance from the produced water out fall. Analysis of chemical fossil ''biomarkers'' provides potentially useful indices of effects of waste discharges upon microbial biodegradation of organic compounds in sediments

  9. Temporal modelling of ballast water discharge and ship-mediated invasion risk to Australia.

    Science.gov (United States)

    Cope, Robert C; Prowse, Thomas A A; Ross, Joshua V; Wittmann, Talia A; Cassey, Phillip

    2015-04-01

    Biological invasions have the potential to cause extensive ecological and economic damage. Maritime trade facilitates biological invasions by transferring species in ballast water, and on ships' hulls. With volumes of maritime trade increasing globally, efforts to prevent these biological invasions are of significant importance. Both the International Maritime Organization and the Australian government have developed policy seeking to reduce the risk of these invasions. In this study, we constructed models for the transfer of ballast water into Australian waters, based on historic ballast survey data. We used these models to hindcast ballast water discharge over all vessels that arrived in Australian waters between 1999 and 2012. We used models for propagule survival to compare the risk of ballast-mediated propagule transport between ecoregions. We found that total annual ballast discharge volume into Australia more than doubled over the study period, with the vast majority of ballast water discharge and propagule pressure associated with bulk carrier traffic. As such, the ecoregions suffering the greatest risk are those associated with the export of mining commodities. As global marine trade continues to increase, effective monitoring and biosecurity policy will remain necessary to combat the risk of future marine invasion events.

  10. Field Evaluation Of Arsenic Transport Across The Ground-Water/Surface Water Interface: Ground-Water Discharge And Iron Oxide Precipitation

    Science.gov (United States)

    A field investigation was conducted to examine the distribution of arsenic in ground water, surface water, and sediments at a Superfund Site in the northeastern United States (see companion presentation by K. G. Scheckel et al). Ground-water discharge into the study area was cha...

  11. Hydrogeologic controls on ground-water and contaminant discharge to the Columbia River near the Hanford Townsite

    International Nuclear Information System (INIS)

    Luttrell, S.P.; Newcomer, D.R.; Teel, S.S.; Vermeul, V.R.

    1992-11-01

    The purpose of this study is to quantify ground-water and contaminant discharge to the Columbia River in the Hanford Townsite vicinity. The primary objectives of the work are to: describe the hydrogeologic setting and controls on ground-water movement and contaminant discharge to the Columbia River; understand the river/aquifer relationship and its effects on contaminant discharge to the Columbia River; quantify the ground-water and contaminant mass discharge to the Columbia River; and provide data that may be useful for a three-dimensional model of ground-water flow and contaminant transport in the Hanford Townsite study area. The majority of ground-water contamination occurs within the unconfined aquifer; therefore, ground-water and contaminant discharge from the unconfined aquifer is the emphasis of this study. The period of study is primarily from June 1990 through March 1992

  12. Variables of state and charateristics for isentropic discharge phenomena of water, starting with saturation

    Energy Technology Data Exchange (ETDEWEB)

    Baudisch, H.

    1968-03-15

    The tables presented in this report contain the thermodynamic values of isentropic change of state for water in the two-phase region starting from the saturation line down to 0.01 at. The variables have been computed in the pressure range from 5-100 at. in equal pressure intervals of 5 at. and in the range from 100-170 at. in intervals of 10 at. Assuming a one-dimensional flow and a known saturation pressure, the dimensions of a discharge nozzle may be determined by interpolation of the calculated values for an isentropic discharge. 4 figs., 29 tabs., 23 refs.

  13. High Power DC Diaphragm Discharge Excited in a Vapor Bubble for the Treatment of Water

    Czech Academy of Sciences Publication Activity Database

    Lukeš, Petr; Člupek, Martin; Babický, Václav; Doležalová, Eva; Sisrová, Irena; Maršálková, Eliška; Maršálek, Blahoslav

    2013-01-01

    Roč. 33, č. 1 (2013), s. 83-95 ISSN 0272-4324 R&D Projects: GA AV ČR IAAX00430802; GA ČR(CZ) GD104/09/H080 Institutional support: RVO:61389021 ; RVO:67985939 Keywords : Diaphragm discharge * Water * Hydrogen peroxide * Phenol * Bacteria * Algae Subject RIV: BL - Plasma and Gas Discharge Physics; EF - Botanics (BU-J) Impact factor: 1.599, year: 2013 http://link.springer.com/content/pdf/10.1007%2Fs11090-012-9432-6.pdf

  14. Corona-like multistreamer discharge in water for cylindrical shock wave generation

    Czech Academy of Sciences Publication Activity Database

    Prukner, Václav; Koláček, Karel; Schmidt, Jiří; Štraus, Jaroslav; Frolov, Oleksandr; Martínková, M.

    2006-01-01

    Roč. 56, suppl.B (2006), s. 342-348 ISSN 0011-4626. [Symposium on Plasma Physics and Technology/22nd./. Praha, 26.6.2006-29.6.2006] R&D Projects: GA ČR GA202/06/1324; GA MŠk 1P04LA235 Institutional research plan: CEZ:AV0Z20430508 Keywords : Shock wave in water * Corona-like multi-streamer discharge Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 0.568, year: 2006

  15. Water recycling from mixed chromic acid waste effluents by membrane technology

    NARCIS (Netherlands)

    Frenzel, I.; Frenzel, I.; Stamatialis, Dimitrios; Wessling, Matthias

    2006-01-01

    Approaching zero discharge waste on site requires economical treatment technologies for the plating industry, recovering high quality rinse water for reuse. The combination of membranes and evaporation could be an efficient way to downsize the cost and the energy intensive evaporation equipment. In

  16. Risk assessment for produced water discharges to Louisiana open bays. Final report

    International Nuclear Information System (INIS)

    Meinhold, A.F.; DePhillips, M.P.; Holtzman, S.

    1996-01-01

    The US Department of Energy (USDOE) has a program of research in the environmental aspects of oil and gas extraction. This sampling project will characterize the environmental impacts associated with the discharge of naturally occurring radioactive materials (NORM), metals and organics in produced water. This report is part of a series of studies of the health and ecological risks from discharges of produced water to the Gulf of Mexico, supported by the USDOE. These assessments are being coordinated with the field study, using the collected data to perform human health and ecological risk assessments. These assessments will provide input to regulators in the development of guidelines and permits, and to industry in the development and use of appropriate discharge practices. The initial human health and ecological risk assessments consist of conservative screening analyses meant to identify potentially important contaminants, and to eliminate others from further consideration. More quantitative assessments were done for contaminants identified, in the screening analysis, as being of potential concern. Section 2 gives an overview of human health and ecological risk assessment to help put the analyses presented here in perspective. Section 3 provides the hazard assessment portion of the risk assessment, and identifies the important receptors and pathways of concern. Section 3 also outlines the approach taken to the risk assessments presented in the rest of the report. The remaining sections (4 through 9) present the human health and ecological risk assessments for discharges of produced water to open bays in Louisiana

  17. Evaluating the vulnerability of surface waters to antibiotic contamination from varying wastewater treatment plant discharges

    International Nuclear Information System (INIS)

    Batt, Angela L.; Bruce, Ian B.; Aga, Diana S.

    2006-01-01

    Effluents from three wastewater treatment plants with varying wastewater treatment technologies and design were analyzed for six antibiotics and caffeine on three sampling occasions. Sulfamethoxazole, trimethoprim, ciprofloxacin, tetracycline, and clindamycin were detected in the effluents at concentrations ranging from 0.090 to 6.0 μg/L. Caffeine was detected in all effluents at concentrations ranging from 0.19 to 9.9 μg/L. These findings indicate that several conventional wastewater management practices are not effective in the complete removal of antibiotics, and their discharges have a large potential to affect the aquatic environment. To evaluate the persistence of antibiotics coming from the wastewater discharges on the surrounding surface waters, samples were collected from the receiving streams at 10-, 20- and 100-m intervals. Ciprofloxacin, sulfamethoxazole, and clindamycin (0.043 to 0.076 μg/L) were found as far as 100 m from the discharge point, which indicates the persistence of these drugs in surface waters. - This work investigates the extent of antibiotic concentrations in receiving waters from discharges of wastewater treatment plants

  18. Acid-base status of soils in groundwater discharge zones — relation to surface water acidification

    Science.gov (United States)

    Norrström, Ann Catrine

    1995-08-01

    Critical load calculations have suggested that groundwater at depth of 2 m in Sweden is very sensitive to acid load. As environmental isotope studies have shown that most of the runoff in streams has passed through the soil, there is a risk in the near future of accelerated acidification of surface waters. To assess the importance of the last soil horizon of contact before discharge, the upper 0-0.2m of soils in seven discharge zones were analysed for pools of base cations, acidity and base saturation. The sites were about 3-4 m 2 in size and selected from two catchments exposed to different levels of acid deposition. The soils in the seven sites had high concentrations of exchangeable base cations and consequently high base saturation. The high correlation ( r2 = 0.74) between base saturation in the soils of the discharge zones and mean pH of the runoff waters suggested that the discharge zone is important for surface water acidification. The high pool of exchangeable base cations will buffer initially against the acid load. As the cation exchange capacity (meq dm -3) and base saturation were lower in the sites from the catchment receiving lower deposition, these streams may be more vulnerable to acidification in the near future. The high concentration of base cations in non-exchangeable fractions may also buffer against acidification as it is likely that some of these pools will become exchangeable with time.

  19. Impact of Leachate Discharge from Cipayung Landfill on Water Quality of Pesanggrahan River, Indonesia

    Science.gov (United States)

    Noerfitriyani, Eki; Hartono, Djoko M.; Moersidik, Setyo S.; Gusniani, Irma

    2018-03-01

    The landfill operation can cause environmental problems due to solid waste decomposition in the form of leachate. The evaluation of environmental impacts related with solid waste landfilling is needed to ensure that leachate discharge to water bodies does not exceed the standard limit to prevent contamination of the environment. This study aims to analyze the impact of leachate discharge from Cipayung Landfill on water quality of Pesanggrahan River. The data were analyzed based on leachate samples taken from influent and effluent treatment unit, and river water samples taken from upstream, stream at leachate discharge, and downstream. All samples were taken three times under rainy season condition from April to May 2017. The results show the average leachate quality temperature is 34,81 °C, TSS 72.33 mg/L, pH 7.83, BOD 3,959.63 mg/L, COD 6,860 mg/L, TN 373.33 mg/L, Hg 0.0016 mg/L. The BOD5/COD ratio 0.58 indicated that leachate characteristics was biodegradable and resemble intermediate landfill due to the mixing of young leachate and old leachate. The effluent of leachate treatment plant exceeds the leachate standard limit for BOD, COD, and TN parameters. Statistical results from independent T-test showed significant differences (p<0,05) between upstream and downstream influenced with leachate discharge for DO parameter.

  20. State waste discharge permit application 400 Area secondary cooling water. Revision 2

    International Nuclear Information System (INIS)

    1996-01-01

    This document constitutes the Washington Administrative Code 173-216 State Waste Discharge Permit Application that serves as interim compliance as required by Consent Order DE 91NM-177, for the 400 Area Secondary Cooling Water stream. As part of the Hanford Federal Facility Agreement and Consent Order negotiations, the US Department of Energy, Richland Operations Office, the US Environmental Protection Agency, and the Washington State Department of Ecology agreed that liquid effluent discharges to the ground on the Hanford Site that affect groundwater or have the potential to affect groundwater would be subject to permitting under the structure of Chapter 173-216 of the Washington Administrative Code, the State Waste Discharge Permitting Program. As a result of this decision, the Washington State Department of Ecology and the US Department of Energy, Richland Operations Office entered into Consent Order DE 91NM-177. The Consent Order DE 91NM-177 requires a series of permitting activities for liquid effluent discharges. Based upon compositional and flow rate characteristics, liquid effluent streams on the Hanford Site have been categorized into Phase 1, Phase 2, and Miscellaneous streams. This document only addresses the 400 Area Secondary Cooling Water stream, which has been identified as a Phase 2 stream. The 400 Area Secondary Cooling Water stream includes contribution streams from the Fuels and Materials Examination Facility, the Maintenance and Storage Facility, the 481-A pump house, and the Fast Flux Test Facility

  1. Removal of NO and SO2 in Corona Discharge Plasma Reactor with Water Film

    Institute of Scientific and Technical Information of China (English)

    贺元吉; 董丽敏; 杨嘉祥

    2004-01-01

    In this paper, a novel type of a corona discharge plasma reactor was designed, which consists of needle-plate-combined electrodes, in which a series of needle electrodes are placed in a glass container filled with flue gas, and a plate electrode is immersed in the water. Based on this model, the removal of NO and SO2 was tested experimentally. In addition, the effect of streamer polarity on the reduction of SO2 and NO was investigated in detail. The experimental results show that the corona wind formed between the high-voltage needle electrode and the water by corona discharge enhances the cleaning efficiency of the flue gas because of the presence of water,and the cleaning efficiency will increase with the increase of applied dc voltage within a definite range. The removal efficiency of SO2 up to 98%, and about 85% of NOx removal under suitable conditions is obtained in our experiments.

  2. Environmental and biotechnological applications of high-voltage pulsed discharges in water

    International Nuclear Information System (INIS)

    Sato, Masayuki

    2008-01-01

    A high-voltage pulse has wide application in fields such as chemistry, physics and biology and their combinations. The high-voltage pulse forms two kinds of physical processes in water, namely (a) a pulsed electric field (PEF) in the parallel electrode configuration and (b) plasma generation by a pulsed discharge in the water phase with a concentrated electric field. The PEF can be used for inactivation of bacteria in liquid foods as a non-thermal process, and the underwater plasma is applicable not only for the decomposition of organic materials in water but also for biological treatment of wastewater. These discharge states are controlled mainly by the applied pulse voltage and the electrode shape. Some examples of environmental and biotechnological applications of a high-voltage pulse are reviewed.

  3. Decline of Yangtze River water and sediment discharge: Impact from natural and anthropogenic changes

    Science.gov (United States)

    Yang, S. L.; Xu, K. H.; Milliman, J. D.; Yang, H. F.; Wu, C. S.

    2015-01-01

    The increasing impact of both climatic change and human activities on global river systems necessitates an increasing need to identify and quantify the various drivers and their impacts on fluvial water and sediment discharge. Here we show that mean Yangtze River water discharge of the first decade after the closing of the Three Gorges Dam (TGD) (2003–2012) was 67 km3/yr (7%) lower than that of the previous 50 years (1950–2002), and 126 km3/yr less compared to the relatively wet period of pre-TGD decade (1993–2002). Most (60–70%) of the decline can be attributed to decreased precipitation, the remainder resulting from construction of reservoirs, improved water-soil conservation and increased water consumption. Mean sediment flux decreased by 71% between 1950–1968 and the post-TGD decade, about half of which occurred prior to the pre-TGD decade. Approximately 30% of the total decline and 65% of the decline since 2003 can be attributed to the TGD, 5% and 14% of these declines to precipitation change, and the remaining to other dams and soil conservation within the drainage basin. These findings highlight the degree to which changes in riverine water and sediment discharge can be related with multiple environmental and anthropogenic factors. PMID:26206169

  4. Spatio-temporal evolution of efficient subglacial water discharge at Lemon Creek Glacier, Alaska

    Science.gov (United States)

    Bartholomaus, T. C.; Labedz, C. R.; Amundson, J. M.; Gimbert, F.; Tsai, V. C.; Vore, M. E.; Karplus, M. S.

    2017-12-01

    The impact of subglacial hydrology on glacier motion, glacier erosion and sediment transport, and submarine melt is well established. However, despite its importance, critical gaps in our understanding of subglacial hydrology and its seasonal evolution remain, in large part due to the challenge of making observations of glacier beds. Thus far, no spatially extensive, temporally continuous observations of subglacial water discharge exist. Seismic signals produced by subglacial water flow, and which correlate with subglacial water discharge, can meet this need. Here, we present the first observations from a 2017 summer seismic, geodetic, and hydrologic experiment. Our experiment seeks to better understand the evolution of efficient subglacial drainage and water storage through data collection and analysis at Lemon Creek Glacier, a 5.7 km-long glacier with a gauged outlet in Southeast Alaska. Data with nested spatial resolutions create an unparalleled perspective of subglacial discharge and its seasonal evolution. Six broadband seismometers and two GPS receivers installed for 80 days provide a long-term view of subglacial discharge and its impact on glacier dynamics. More than 100 nodes, installed approximately every 250 m over the glacier surface ( 13 nodes per 1 km^2) and deployed for up to 25 days, reveal the detailed spatial pattern of glaciohydraulic tremor amplitudes. These nodes enable us to more precisely infer the locations of subglacial discharge and its change, as well as better interpret long-term patterns of glaciohydraulic tremor observed by the broadband seismometers. We infer the subglacial response to hydraulic transients over the duration of the deployment through examination of intermittent melt and rain events, and the abrupt drainage of a glacier-dammed lake. These observations demonstrate the promise of seismology to significantly advance our understanding of glacier hydrology and associated glaciological processes.

  5. 30 CFR 250.248 - What solid and liquid wastes and discharges information and cooling water intake information must...

    Science.gov (United States)

    2010-07-01

    ... following solid and liquid wastes and discharges information and cooling water intake information must... 30 Mineral Resources 2 2010-07-01 2010-07-01 false What solid and liquid wastes and discharges information and cooling water intake information must accompany the DPP or DOCD? 250.248 Section 250.248...

  6. Residence times and nitrate transport in ground water discharging to streams in the Chesapeake Bay Watershed

    Science.gov (United States)

    Lindsey, Bruce D.; Phillips, Scott; Donnelly, Colleen A.; Speiran, Gary K.; Plummer, Niel; Bohlke, John Karl; Focazio, Michael J.; Burton, William C.; Busenberg, Eurybiades

    2003-01-01

    One of the major water-quality problems in the Chesapeake Bay is an overabundance of nutrients from the streams and rivers that discharge to the Bay. Some of these nutrients are from nonpoint sources such as atmospheric deposition, agricultural manure and fertilizer, and septic systems. The effects of efforts to control nonpoint sources, however, can be difficult to quantify because of the lag time between changes at the land surface and the response in the base-flow (ground water) component of streams. To help resource managers understand the lag time between implementation of management practices and subsequent response in the nutrient concentrations in the base-flow component of streamflow, a study of ground-water discharge, residence time, and nitrate transport in springs throughout the Chesapeake Bay Watershed and in four smaller watersheds in selected hydrogeomorphic regions (HGMRs) was conducted. The four watersheds were in the Coastal Plain Uplands, Piedmont crystalline, Valley and Ridge carbonate, and Valley and Ridge siliciclastic HGMRs.A study of springs to estimate an apparent age of the ground water was based on analyses for concentrations of chlorofluorocarbons in water samples collected from 48 springs in the Chesapeake Bay Watershed. Results of the analysis indicate that median age for all the samples was 10 years, with the 25th percentile having an age of 7 years and the 75th percentile having an age of 13 years. Although the number of samples collected in each HGMR was limited, there did not appear to be distinct differences in the ages between the HGMRs. The ranges were similar between the major HGMRs above the Fall Line (modern to about 50 years), with only two HGMRs of small geographic extent (Piedmont carbonate and Mesozoic Lowland) having ranges of modern to about 10 years. The median values of all the HGMRs ranged from 7 to 11 years. Not enough samples were collected in the Coastal Plain for comparison. Spring samples showed slightly younger

  7. Meteorological, stream-discharge, and water-quality data for water year 1992 from two basins in Central Nevada

    International Nuclear Information System (INIS)

    McKinley, P.W.; Oliver, T.A.

    1995-01-01

    The US Geological Survey, in cooperation with the US Department of Energy, is studying Yucca Mountain, Nevada, as a potential repository for high level nuclear waste. As part of the Yucca Mountain Site Project, the analog recharge study is providing data for the evaluation of recharge to the Yucca Mountain ground-water system given a cooler and wetter climate than currently exists. The current and climatic conditions are favorable to the isolation of radioactive waste. Because waste isolation from the accessible environment for 10,000 years is necessary, climatic change and the potential for increased ground-water recharge need to be considered as part of the characterization of the potential repository. Therefore, two small basins, measuring less than 2 square miles, were studied to determine the volume of precipitation available for recharge to ground water. The semiarid 3-Springs Basin is located to the east of Kawich Peak in the Kawich Range east of Tonopah, Nevada. Stewart Basin is a subalpine drainage basin north of Arc Dome in the Toiyabe Range north of Tonopah, Nevada. The purpose of this publication is to make available the meteorological, stream-discharge, and water-quality data collected during the study. Meteorological data collected include air temperature, soil temperature, solar radiation, and relative humidity. Stream-discharge data were collected from the surface-water outlet of each basin. Water-quality data are chemical analyses of water samples collected from surface- and ground-water sources. Each basin has a meteorological station located in the lower and upper reaches of the basin. Hydrologic records include stream-discharge and water-quality data from the lower meteorological site and water-quality data from springs within the basins

  8. Analysis of thermo-hydraulic behavior of coolant during discharge of pressurized high-temperature water

    International Nuclear Information System (INIS)

    Suzuki, Mitsuhiro; Sobajima, Makoto; Sasaki, Shinobu; Onishi, Nobuaki; Shiba, Masayoshi

    1978-01-01

    The present report describes results of the analysis of the LOFT semiscale experiment No. 1011 using remodeled RELAP-3 code, performed at the Idaho National Engineering Laboratory to simulate a postulated loss-of-coolant accident in a pressurized water reactor. It was clarified through the analysis that coolant behavior during blowdown was influenced variously by the system components in the primary loop, comparing with coolant discharge from a pressure vessel. Good agreement was obtained between experimental and analytical results when phase separation was assumed in upper plenum and downcomer, since experimental data indicated existence of liquid level in those parts. It was also found that the use of the Wilson's equation to calculate bubble rise velocity and the use of discharge coefficient as the function of fluid quality at break location to calculate discharge flow rate resulted in good agreement with experimental data. (auth.)

  9. Determination of mercury in discharge water from plastic manufactory by neutron activation analysis and copper powder adsorption

    Energy Technology Data Exchange (ETDEWEB)

    Houng-Huei, L [National Tsing Hua University Hsinchu, Taiwan (Republic of China)

    1979-02-28

    Through copper powder adsorption, neutron activation analysis was used to determine the mercury in discharge water from a plastic manufactory where the water samples were taken from various discharge ditches. The experimental results showed that waste water from mercury cells contained 1.7x10/sup -9/ approximately 8.19x10/sup -6/ g Hg/ml while water samples taken from other areas did not show significant mercury level and were below the limit of detection.

  10. The behaviour of water discharged into the subsoil in a dolomitic mining area

    International Nuclear Information System (INIS)

    De Jesus, A.S.M.

    1989-01-01

    Water extracted from the underground works, at a depth of approximately 1 000 m, in a mine situated in a dolomitic area was being discharged into a series of boreholes on the surface. It was, however, presumed, that some recirculation was occurring. A tracer investigation was carried out to assess whether at least some of the water was reaching the underground works and the transit times involved. Since indium can be determined by means of neutron activation analysis at concentration levels as low as 10 -11 g/l water, this element was selected as tracer. The results are discussed. 9 refs., 5 figs

  11. Regulation, characterization and treatment of discharge waters from pipelines. Volume 1. Topical report, January 1989-April 1992. Executive summary

    International Nuclear Information System (INIS)

    Tallon, J.T.; Fillo, J.P.

    1992-04-01

    The report examines environmental issues related to hydrostatic testing of discharge waters generated from integrity testing of natural gas pipelines. Hydrostatic testing, and proper environmental management of the discharge waters, can be required by DOT regulations. However, disposal of water used to conduct a hydrostatic pipeline test is regulated on a state-by-state basis. State-specific requirements vary widely, ranging from an authorization letter to a complete NPDES permit. Monitoring may be required before and during discharge, include a variety of analyses, have varying protocols for obtaining samples, and may be required either to obtain data or to ascertain compliance with stipulated discharge limits. The composition of the discharge and state-specific discharge limitations dictate treatment needs on a case-by-case basis. The volume consists of the Executive Summary of a five-volume report series

  12. Exploring Numerically the Benefits of Water Discharge Prediction for the Remote RTC of WDNs

    Directory of Open Access Journals (Sweden)

    Enrico Creaco

    2017-12-01

    Full Text Available This paper explores numerically the benefits of water discharge prediction in the real time control (RTC of water distribution networks (WDNs. An algorithm aimed at controlling the settings of control valves and variable speed pumps, as a function of pressure head signals from remote nodes in the network, is used. Two variants of the algorithm are considered, based on the measured water discharge in the device at the current time and on the prediction of this variable at the new time, respectively. As a result of the prediction, carried out using a polynomial with coefficients determined through linear regression, the RTC algorithm attempts to correct the expected deviation of the controlled pressure head from the set point, rather than the currently measured deviation. The applications concerned the numerical simulation of RTC in a WDN, in which the nodal demands are reconstructed stochastically through the bottom-up approach. The results prove that RTC benefits from the implementation of the prediction, in terms of the closeness of the controlled variable to the set point and of total variations of the device setting. The benefits are more evident when the water discharge features contained random fluctuations and large hourly variations.

  13. Wastewater discharge impact on drinking water sources along the Yangtze River (China).

    Science.gov (United States)

    Wang, Zhuomin; Shao, Dongguo; Westerhoff, Paul

    2017-12-01

    Unplanned indirect (de facto) wastewater reuse occurs when wastewater is discharged into surface waters upstream of potable drinking water treatment plant intakes. This paper aims to predict percentages and trends of de facto reuse throughout the Yangtze River watershed in order to understand the relative contribution of wastewater discharges into the river and its tributaries towards averting water scarcity concerns. The Yangtze River is the third longest in the world and supports more than 1/15 of the world's population, yet the importance of wastewater on the river remains ill-defined. Municipal wastewater produced in the Yangtze River Basin increased by 41% between 1998 and 2014, from 2580m 3 /s to 3646m 3 /s. Under low flow conditions in the Yangtze River near Shanghai, treated wastewater contributions to river flows increased from 8% in 1998 to 14% in 2014. The highest levels of de facto reuse appeared along a major tributary (Han River) of the Yangtze River, where de facto reuse can exceed 20%. While this initial analysis of de facto reuse used water supply and wastewater data from 110 cities in the basin and 11 gauging stations with >50years of historic streamflow data, the outcome was limited by the lack of gauging stations at more locations (i.e., data had to be predicted using digital elevation mapping) and lack of precise geospatial location of drinking water intakes or wastewater discharges. This limited the predictive capability of the model relative to larger datasets available in other countries (e.g., USA). This assessment is the first analysis of de facto wastewater reuse in the Yangtze River Basin. It will help identify sections of the river at higher risk for wastewater-related pollutants due to presence of-and reliance on-wastewater discharge that could be the focus of field studies and model predictions of higher spatial and temporal resolution. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Generation of reactive species in atmospheric pressure dielectric barrier discharge with liquid water

    Science.gov (United States)

    Zelong, ZHANG; Jie, SHEN; Cheng, CHENG; Zimu, XU; Weidong, XIA

    2018-04-01

    Atmospheric pressure helium/water dielectric barrier discharge (DBD) plasma is used to investigate the generation of reactive species in a gas-liquid interface and in a liquid. The emission intensity of the reactive species is measured by optical emission spectroscopy (OES) with different discharge powers at the gas-liquid interface. Spectrophotometry is used to analyze the reactive species induced by the plasma in the liquid. The concentration of OH radicals reaches 2.2 μm after 3 min of discharge treatment. In addition, the concentration of primary long-lived reactive species such as H2O2, {{{{NO}}}3}- and O3 are measured based on plasma treatment time. After 5 min of discharge treatment, the concentration of H2O2, {{{{NO}}}3}-, and O3 increased from 0 mg · L-1 to 96 mg · L-1, 19.5 mg · L-1, and 3.5 mg · L-1, respectively. The water treated by plasma still contained a considerable concentration of reactive species after 6 h of storage. The results will contribute to optimizing the DBD plasma system for biological decontamination.

  15. Statistical prediction of seasonal discharge in the Naryn basin for water resources planning in Central Asia

    Science.gov (United States)

    Apel, Heiko; Gafurov, Abror; Gerlitz, Lars; Unger-Shayesteh, Katy; Vorogushyn, Sergiy; Merkushkin, Aleksandr; Merz, Bruno

    2016-04-01

    The semi-arid regions of Central Asia crucially depend on the water resources supplied by the mountainous areas of the Tien-Shan and Pamirs. During the summer months the snow and glacier melt water of the rivers originating in the mountains provides the only water resource available for agricultural production but also for water collection in reservoirs for energy production in winter months. Thus a reliable seasonal forecast of the water resources is crucial for a sustainable management and planning of water resources.. In fact, seasonal forecasts are mandatory tasks of national hydro-meteorological services in the region. Thus this study aims at a statistical forecast of the seasonal water availability, whereas the focus is put on the usage of freely available data in order to facilitate an operational use without data access limitations. The study takes the Naryn basin as a test case, at which outlet the Toktogul reservoir stores the discharge of the Naryn River. As most of the water originates form snow and glacier melt, a statistical forecast model should use data sets that can serve as proxy data for the snow masses and snow water equivalent in late spring, which essentially determines the bulk of the seasonal discharge. CRU climate data describing the precipitation and temperature in the basin during winter and spring was used as base information, which was complemented by MODIS snow cover data processed through ModSnow tool, discharge during the spring and also GRACE gravimetry anomalies. For the construction of linear forecast models monthly as well as multi-monthly means over the period January to April were used to predict the seasonal mean discharge of May-September at the station Uchterek. An automatic model selection was performed in multiple steps, whereas the best models were selected according to several performance measures and their robustness in a leave-one-out cross validation. It could be shown that the seasonal discharge can be predicted with

  16. Desalination Brine Discharge Impacts on Coastal Biology and Water Chemistry - A Case Study from Carlsbad Southern California

    Science.gov (United States)

    Petersen, K. L.; Heck, N.; Potts, D. C.; Paytan, A.

    2017-12-01

    Fresh water demand is increasing world-wide due to on-going droughts, climate change and increasing human population and associated demand for food and water. Desalination of seawater is a reliable source of potable water; however the effects of byproduct brine discharge from desalination plants on coastal areas have not been thoroughly assessed. Here we report results from in-situmeasurements of the effects of brine discharge on water chemistry and coastal biology from a desalination plant in Carlsbad, Southern California. We compared select parameters in the coastal zone around the discharge site before and after operation began and conducted additional controlled laboratory incubations with key coastal species and brine effluent. Our in-situ data shows differences in salinity and temperature between the discharge area and a control site both before and after the desalination plant started operation. The discharge water is warmer by 3-5 Co than the ambient seawater and a temperature gradient is seen around the discharge channel. This is likely a result of mixing of the desalination brine with power plant cooling water for dilution prior to discharge and the higher temperatures are not directly attributed to the desalination. Our post-discharge results show a decipherable salinity plume at the bottom of the water column ( 6 m depth) reaching up to 600 m offshore from the discharge site. This indicates inefficient mixing of the brine in the coastal discharge zone. No significant differences are found in nutrient levels, organic carbon or chlorophyll a concentrations around the discharge. The benthic biology assemblage post-discharge is significantly different from the pre-discharge organisms' assemblage. However, the role of seasonal changes in temperature may also have impacted the data as the sampling was conducted during different seasons. Controlled incubation experiments of brittle stars (Ophiothrix spiculata) shows no significant difference in growth or

  17. Determination of 90Sr in waters of discharge of nuclear power plants

    International Nuclear Information System (INIS)

    Campos, J.M.; Equillor, H.E.

    2010-01-01

    The determination of 90 Sr has some problems because it is a pure beta emitter, and despite the specificity of radiochemical techniques used, their full identification is not always easy, especially when detected low activities. In addition, samples water discharge presents a matrix consisting of a series of fission or activation products, beta / gamma emitters, several of which may interfere with the determination of 90 Sr. This paper describes a simple method for the determination of 90 Sr in water of discharge of nuclear power plants, which is based on the purification of 90 Y, which is used in the ARN since 2009 and has yielded good results to the present, as no interferences were detected in the analysis of the decay of 90 Y. (authors) [es

  18. The seat of ground water discharge as ore-mabilizing factor in the formatian of hydrogenic uranium deposits

    International Nuclear Information System (INIS)

    Natal'chenko, B.I.; Gol'dshtejn, R.I.

    1982-01-01

    The role of structural-hydrogeological factor in the process of ore-controlling zoning development during hydrogeneous deposit formation is discussed, as reflecting in the most objective way the spreading of stratal oxidation zones and morphology of uranium mineralization as regards discharge seats because there are only they which mobilize stratal waters for active displacement. The types of discharge seats of stratal waters and their effect on formation of ore-controlling zones of stratal oxidation with uranium mineralization are presented. The conclusion is drawn that local and regional discharge seats of stratal waters dictate both the spacing of regional fronts of stratal-oxidized rocks and their ore content degree. The displacement of discharge seats or their growing into local regions of alimentation results in reorganization of the total ore-controlling zoning, which enables to consider the seats of water discharge as ore-mobilizing structures in the formation of hydrogenic uranium deposits

  19. Water quality and discharge data for St. Joseph Bay, Florida, 1997-98

    Science.gov (United States)

    Berndt, M.P.; Franklin, M.A.

    1999-01-01

    Historical data were compiled on water quality and water levels for the St. Joseph Bay area to assess quality of possible sources of land-derived water into the Bay. Ground-water quality data were compiled from Florida Department of Environmental Protection and surface-water quality data were compiled from U.S.Geological Survey files. Water-quality and water-level data were measured during two sample collection periods in October 1997 and March 1998 to determine water-quality and discharge rates in St. Joseph Bay under two sets of flow conditions. Measurements in the Bay included water level, temperature, pH, specific conductance, dissolved oxygen, and turbidity. Median pH in water from the surficial, intermediate and Floridan aquifer systems ranged from 4.8 to 7.8, and median specific conductance values were less than 500 microsiemens per centimeter. Median nutrient concentrations-- nitrate plus nitrite, ammonia and phosphorus--in the three aquifers were less than 0.5 milligrams per liter. The median pH was 7.0 and the median specific conductance was 81 microsiemens per centimeter for two samples from the Chipola River distribution canal. Water level data were obtained for several wells near St. Joseph Bay but only two wells yielded sufficient data to plot hydrographs. Measurements in St. Joseph Bay during the October and March collection periods were similar for pH and turbidity but differed for temperature, specific conductance and dissolved oxygen. The median temperature was 20.6 degrees Celsius in October and 15.4 degrees Celsius in March, median specific conductance was 39,500 microsiemens per centimeter in October and 43,300 microsiemens per centimeter in March, and median dissolved oxygen was 7.6 milligrams per liter in October and 8.3 milligrams per liter in March. The range in water levels over a tidal cycle in St. Joseph Bay on October 29, 1997 was about 1 foot. During a 24-hour tidal cycle on October 29, 1997, estimated hourly discharge varied from

  20. Dependency of high coastal water level and river discharge at the global scale

    Science.gov (United States)

    Ward, P.; Couasnon, A.; Haigh, I. D.; Muis, S.; Veldkamp, T.; Winsemius, H.; Wahl, T.

    2017-12-01

    It is widely recognized that floods cause huge socioeconomic impacts. From 1980-2013, global flood losses exceeded $1 trillion, with 220,000 fatalities. These impacts are particularly hard felt in low-lying densely populated deltas and estuaries, whose location at the coast-land interface makes them naturally prone to flooding. When river and coastal floods coincide, their impacts in these deltas and estuaries are often worse than when they occur in isolation. Such floods are examples of so-called `compound events'. In this contribution, we present the first global scale analysis of the statistical dependency of high coastal water levels (and the storm surge component alone) and river discharge. We show that there is statistical dependency between these components at more than half of the stations examined. We also show time-lags in the highest correlation between peak discharges and coastal water levels. Finally, we assess the probability of the simultaneous occurrence of design discharge and design coastal water levels, assuming both independence and statistical dependence. For those stations where we identified statistical dependency, the probability is between 1 and 5 times greater, when the dependence structure is accounted for. This information is essential for understanding the likelihood of compound flood events occurring at locations around the world as well as for accurate flood risk assessments and effective flood risk management. The research was carried out by analysing the statistical dependency between observed coastal water levels (and the storm surge component) from GESLA-2 and river discharge using gauged data from GRDC stations all around the world. The dependence structure was examined using copula functions.

  1. Nitrates in Groundwater Discharges from the Azores Archipelago: Occurrence and Fluxes to Coastal Waters

    Directory of Open Access Journals (Sweden)

    J. Virgílio Cruz

    2017-02-01

    Full Text Available Groundwater discharge is an important vector of chemical fluxes to the ocean environment, and as the concentration of nutrients is often higher in discharging groundwater, the deterioration of water quality in the receiving environment can be the result. The main objective of the present paper is to estimate the total NO3 flux to coastal water bodies due to groundwater discharge in the volcanic Azores archipelago (Portugal. Therefore, 78 springs discharging from perched-water bodies have been monitored since 2003, corresponding to cold (mean = 14.9 °C and low mineralized (47.2–583 µS/cm groundwater from the sodium-bicarbonate to sodium-chloride water types. A set of 36 wells was also monitored, presenting groundwater with a higher mineralization. The nitrate content in springs range between 0.02 and 37.4 mg/L, and the most enriched samples are associated to the impact of agricultural activities. The total groundwater NO3 flux to the ocean is estimated in the range of 5.23 × 103 to 190.6 × 103 mol/km2/a (∑ = ~523 × 103 mol/km2/a, exceeding the total flux associated to surface runoff (∑ = ~281 × 103 mol/km2/a. In the majority of the islands, the estimated fluxes are higher than runoff fluxes, with the exception of Pico (47.2%, Corvo (46% and Faial (7.2%. The total N-NO3 flux estimated in the Azores (~118.9 × 103 mol/km2/a is in the lower range of estimates made in other volcanic islands.

  2. Study of Ag and Au Nanoparticles Synthesized by Arc Discharge in Deionized Water

    Directory of Open Access Journals (Sweden)

    Der-Chi Tien

    2010-01-01

    Full Text Available The paper presents a study of Ag and Au nanofluids synthesized by the arc discharge method (ADM in deionized water. The metallic Ag nanoparticle (Ag0 and ionic Ag (Ag+ have played an important role in the battle against germs which are becoming more drug-resistant every year. Our study indicates that Ag nanoparticle suspension (SNPS fabricated by using ADM without added surfactants exclusively contains the metallic Ag nanoparticle and ionic Ag. Besides that, the ADM in deionized water has also been employed for the fabrication process of Au nanoparticles. The experimental results indicate that the prepared Ag nanoparticles can react with the dissolved H2CO3 in deionized water, leading to the formation of Ag2CO3. Significantly different to Ag, the prepared Au nanoparticles with their surfaces bonded by oxygen are suspended in deionized water by the formation of hydrogen bonded with the neighboring water molecules.

  3. Water-rock interactions in discharge areas of Xiangshan Fossil hydrothermal system

    International Nuclear Information System (INIS)

    Zhou, Wenbin

    1992-01-01

    Xiangshan Fossil hydrothermal system is located within a volcanic basin of south-eastern China. The fact that most metal mineralizations were found in the discharge areas of the fossil hydrothermal system shows that the discharge areas were special geochemical fields. This paper discusses some important water-rock interactions in the discharge areas of Xiangshan fossil hydrothermal system. When the fluids circulating in the deep section of the hydrothermal system went upward to the discharge area, the physico-chemical conditions under which the fluids were saturated changed so considerably that the original physico-chemical equilibria were broken. Consequently, the fluids tended to move to new equilibrium by means of regulating their chemical compositions. Temperature and pressures of the fluids could be declined greatly in discharge area; the difference of temperature and pressure are determined to be 100--150 C and 1--2 x 10 7 Pa. As a result, a large amount of CO 2 in solution escaped from the fluids in the discharge area, and UO 2 (CO 3 ) n 2(1-n) , stable in CO 2 -rich solutions, could be decomposed into UUO 2 2+ , which could be easily reduced into pitchblende associated by calcite and hematite. The pH values for the fluids tended to increase with the CO 2 escaping, however, the interactions between the hydrothermal fluids and the wall rocks (dominantly aluminosilicate) served as the buffers for the pH, and regulated the pH value around neutral point. The buffer effect was of great importance to uranium mineralization. In addition, isotope exchangements between the fluids and rocks took place extensively

  4. Recharge and discharge areas of the Floridan Aquifer in the St. Johns River Water Management District and vicinity, Florida

    Science.gov (United States)

    Phelps, G.G.

    1984-01-01

    The Floridan aquifer is the principal source of most of the freshwater used in the St. Johns River Water Management District. An important step in managing water resources is the delineation of recharge and discharge areas. Geohydrologic factors to be considered when delineating recharge and discharge areas include: altitude and configuration of the potentiometric surface; direction and magnitude of the gradient between the water table and the potentiometric surface; and thickness and permeability of the overlying sediments. Recharge to the aquifer comes almost entirely from rainfall within the Water Management District. Significant recharge occurs where the aquifer is at or very near land surface, and where the overlying sediments are very permeable sand so that recharge takes place downward leakage. Recharge also occurs through sinkholes, sinkhole lakes, and other lakes that have a good connection to the aquifer. Major recharge areas are delineated on the map. Discharge occurs in areas of artesian flow (where the potentiometric surface is above land surface), primarily by diffuse upward leakage and by discharge from springs. Fifty-five springs, with total discharge of about 1,600 million gallons per day, are in the Water Management District. Areas of discharge and the location of springs are shown on the map. In 1980, total pumpage in the Water Management District was about 1,000 million gallons per day. Under predevelopment conditions, discharge by springs and upward leakage approximately balanced recharged. Additional discharge by pumpage may or may not be balanced by decreased spring discharge of increased downward leakage. Examination of long-term water level trends can indicate if recharge and discharge balance. Graphs of rainfall, water levels, and municipal pumpage for Jacksonville, Orlando, and Daytona Beach are shown on the map. (USGS)

  5. Research on the degradation mechanism of dimethyl phthalate in drinking water by strong ionization discharge

    Science.gov (United States)

    Hong, ZHAO; Chengwu, YI; Rongjie, YI; Huijuan, WANG; Lanlan, YIN; I, N. MUHAMMAD; Zhongfei, MA

    2018-03-01

    The degradation mechanism of dimethyl phthalate (DMP) in the drinking water was investigated using strong ionization discharge technology in this study. Under the optimized condition, the degradation efficiency of DMP in drinking water was up to 93% in 60 min. A series of analytical techniques including high-performance liquid chromatography, liquid chromatography mass spectrometry, total organic carbon analyzer and ultraviolet-visible spectroscopy were used in the study. It was found that a high concentration of ozone (O3) produced by dielectric barrier discharge reactor was up to 74.4 mg l-1 within 60 min. Tert-butanol, isopropyl alcohol, carbonate ions ({{{{CO}}}3}2-) and bicarbonate ions ({{{{HCO}}}3}-) was added to the sample solution to indirectly prove the presence and effect of hydroxyl radicals (·OH). These analytical findings indicate that mono-methyl phthalate, phthalic acid (PA) and methyl ester PA were detected as the major intermediates in the process of DMP degradation. Finally, DMP and all products were mineralized into carbon dioxide (CO2) and water (H2O) ultimately. Based on these analysis results, the degradation pathway of DMP by strong ionization discharge technology were proposed.

  6. Nutrient Enrichment in Estuaries from Discharge of Shallow Ground Water, Mt. Desert Island, Maine

    Science.gov (United States)

    Culbertson, Charles W.; Huntington, Thomas G.; Caldwell, James M.

    2007-01-01

    Nutrient enrichment from atmospheric deposition, agricultural activities, wildlife, and domestic sources is a concern at Acadia National Park because of the potential problem of water-quality degradation and eutrophication in its estuaries. Water-quality degradation has been observed at the Park?s Bass Harbor Marsh estuary but not in Northeast Creek estuary. Previous studies at Acadia National Park have estimated nutrient inputs to estuaries from atmospheric deposition and surface-water runoff, but the importance of shallow ground water that may contain nutrients derived from domestic or other sources is unknown. Northeast Creek and Bass Harbor Marsh estuaries were studied to (1) identify shallow ground-water seeps, (2) assess the chemistry of the water discharged from selected seeps, and (3) assess the chemistry of ground water in shallow ground-water hyporheic zones. The hyporheic zone is defined here as the region beneath and lateral to a stream bed, where there is mixing of shallow ground water and surface water. This study also provides baseline chemical data for ground water in selected bedrock monitoring wells and domestic wells on Mt. Desert Island. Water samples were analyzed for concentrations of nutrients, wastewater compounds, dissolved organic carbon, pH, dissolved oxygen, temperature and specific conductance. Samples from bedrock monitoring wells also were analyzed for alkalinity, major cations and anions, and trace metals. Shallow ground-water seeps to Northeast Creek and Bass Harbor Marsh estuaries at Acadia National Park were identified and georeferenced using aerial infrared digital imagery. Monitoring included the deployment of continuously recording temperature and specific conductance sensors in the seep discharge zone to access marine or freshwater signatures related to tidal flooding, gradient-driven shallow ground-water flow, or shallow subsurface flow related to precipitation events. Many potential shallow ground-water discharge zones were

  7. Impacts from oil and gas produced water discharges on the Gulf of Mexico hypoxic zone

    International Nuclear Information System (INIS)

    Parker, M.E.; Satterlee, K.; Veil, J.A.

    2006-01-01

    Shallow water areas of the Gulf of Mexico continental shelf experience low dissolved oxygen (hypoxia) each summer. The hypoxic zone is primarily caused by input of nutrients from the Mississippi and Atchafalaya Rivers. The nutrients stimulate the growth of phytoplankton, which leads to reduction of the oxygen concentration near the sea floor. During the renewal of an offshore discharge permit used by the oil and gas industry in the Gulf of Mexico, the U.S. Environmental Protection Agency (EPA) identified the need to assess the potential contribution from produced water discharges to the occurrence of hypoxia. The EPA permit required either that all platforms in the hypoxic zone submit produced water samples, or that industry perform a coordinated sampling program. This paper, based on a report submitted to EPA in August 2005 (1), describes the results of the joint industry sampling program and the use of those results to quantify the relative significance of produced water discharges in the context of other sources on the occurrence of hypoxia in the Gulf of Mexico. In the sampling program, 16 facilities were selected for multiple sampling - three times each at one month intervals-- and another 34 sites for onetime sampling. The goal of the sampling program was to quantify the sources and amount of oxygen demand associated with a variety of Gulf of Mexico produced waters. Data collected included direct oxygen demand measured by BOD5 (5-day biochemical oxygen demand) and TOC (total organic carbon) and indirect oxygen demand measured by nitrogen compounds (ammonia, nitrate, nitrate, and TKN (total Kjeldahl nitrogen)) and phosphorus (total phosphorus and orthophosphate). These data will serve as inputs to several available computer models currently in use for forecasting the occurrence of hypoxia in the Gulf of Mexico. The output of each model will be compared for consistency in their predictions and then a semi-quantitative estimate of the relative significance of

  8. The application of zero-water discharge system in treating diffuse village wastewater and its benefits in community afforestation

    Energy Technology Data Exchange (ETDEWEB)

    Wu Yonghong, E-mail: yhwu@issas.ac.cn [State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Sciences, Chinese Academy of Sciences, 71 Beijing East Road, Nanjing 210008 (China); College of Resource and Environment, Graduate University, Chinese Academy of Sciences, Beijing 100049 (China); Xia Lizhong [State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Sciences, Chinese Academy of Sciences, 71 Beijing East Road, Nanjing 210008 (China); Hu Zhengyi [State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Sciences, Chinese Academy of Sciences, 71 Beijing East Road, Nanjing 210008 (China); College of Resource and Environment, Graduate University, Chinese Academy of Sciences, Beijing 100049 (China); Liu Shuzhi [Kunming Institute of Environmental Sciences, Kunming Environmental Protection Agency, Kunming 650000 (China); Liu, Hongbin [Institute of Agricultural Resource and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081 (China); Nath, Bibhash [School of Geosciences, The University of Sydney, Sydney, NSW 2006 (Australia); Zhang Naiming [College of Resource and Environment, Yunnan Agriculture University, Kunming 650201 (China); Yang, Linzhang, E-mail: Lzyang@issas.ac.cn [State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Sciences, Chinese Academy of Sciences, 71 Beijing East Road, Nanjing 210008 (China)

    2011-10-15

    The proposed on-site zero-water discharge system was comprised of four main components: anaerobic tank, aerobic bioreactor, activated soil filter and water-collecting well. The results demonstrate that at 350 m{sup 3} day{sup -1} of hydraulic load, the system can effectively remove pollutants from the wastewater, e.g., 86% removal of COD; 87% removal of SS; 80% removal of TP and 71% removal of TN. The growth states of the grasses, macrophytes and arbors in the activated soil filter were better than the control. The life of the activated soil filter was estimated to be {approx}12-15 yrs, based on the laboratory microcosm studies. However, humic acid contents and soil porosity have suggested that the activated soil filter was able to regenerate itself and thereby prolonging its life by reducing clogging of the pores. The results suggest that the zero-water discharge system was a promising bio-measure in treating diffuse village wastewater and benefiting community afforestation. - Highlights: > No wastewater discharges out of the zero-water discharge system during this system running. > The zero-water discharge system can efficiently remove COD, SS, TP, and TN from wastewater. > The zero-water discharge system can benefit the community afforestation. - A zero-water discharge system has proven highly-effective for removing COD, SS, TP, and TN from diffuse village wastewater and benefiting the community afforestation.

  9. EFFECT OF THE CRITICAL IRRADIANCE ON PHOTOVOLTAIC WATER PUMP DISCHARGE UNDER EGYPTIAN CONDITIONS

    Directory of Open Access Journals (Sweden)

    Mamdouh Abbas HELMY

    2015-04-01

    Full Text Available The present investigation aimed to study the effect of critical irradiance due to changing tilt angle of PV panel and tracking sun on submersible pump discharge. The authors used solar tracker and suitable tilt angle for the panel to increase the time interval during which the water pump operates. For the same irradiance collected by the PV, all systems pump the same amount of water, although they occur at different periods of the day. The pump itself 'does not know whether the electric power comes from any processes, as long as it has the same intensity.

  10. Discharge, water quality, and native fish abundance in the Virgin River, Utah, Nevada, and Arizona, in support of Pah Tempe Springs discharge remediation efforts

    Science.gov (United States)

    Miller, Matthew P.; Lambert, Patrick M.; Hardy, Thomas B.

    2014-01-01

    Pah Tempe Springs discharge hot, saline, low dissolved-oxygen water to the Virgin River in southwestern Utah, which is transported downstream to Lake Mead and the Colorado River. The dissolved salts in the Virgin River negatively influence the suitability of this water for downstream agricultural, municipal, and industrial use. Therefore, various remediation scenarios to remove the salt load discharged from Pah Tempe Springs to the Virgin River are being considered. One concern about this load removal is the potential to impact the ecology of the Virgin River. Specifically, information is needed regarding possible impacts of Pah Tempe Springs remediation scenarios on the abundance, distribution, and survival of native fish in the Virgin River. Future efforts that aim to quantitatively assess how various remediation scenarios to reduce the load of dissolved salts from Pah Tempe Springs into the Virgin River may influence the abundance, distribution, and survival of native fish will require data on discharge, water quality, and native fish abundance. This report contains organized accessible discharge, water quality, and native fish abundance data sets from the Virgin River, documents the compilation of these data, and discusses approaches for quantifying relations between abiotic physical and chemical conditions, and fish abundance.

  11. Efficacy of dental rinse formulations marketed in Abuja, Nigeria in ...

    African Journals Online (AJOL)

    This study assessed the microbial quality and effectiveness of seven brands of antiseptic dental rinses marketed in Abuja, Nigeria. Seven brands of dental rinses were randomly purchased from the open market and pharmacies. According to the products literature, the brands contained sodium fluoride + triclosan, sodium ...

  12. Multi-Model Assessment of Global Hydropower and Cooling Water Discharge Potential Under Climate Change

    Science.gov (United States)

    van Vliet, M. T. H.; van Beek, L. P. H.; Eisener, S.; Wada, Y.; Bierkens, M. F. P.

    2016-01-01

    Worldwide, 98% of total electricity is currently produced by thermoelectric power and hydropower. Climate change is expected to directly impact electricity supply, in terms of both water availability for hydropower generation and cooling water usage for thermoelectric power. Improved understanding of how climate change may impact the availability and temperature of water resources is therefore of major importance. Here we use a multi-model ensemble to show the potential impacts of climate change on global hydropower and cooling water discharge potential. For the first time, combined projections of streamflow and water temperature were produced with three global hydrological models (GHMs) to account for uncertainties in the structure and parametrization of these GHMs in both water availability and water temperature. The GHMs were forced with bias-corrected output of five general circulation models (GCMs) for both the lowest and highest representative concentration pathways (RCP2.6 and RCP8.5). The ensemble projections of streamflow and water temperature were then used to quantify impacts on gross hydropower potential and cooling water discharge capacity of rivers worldwide. We show that global gross hydropower potential is expected to increase between +2.4% (GCM-GHM ensemble mean for RCP 2.6) and +6.3% (RCP 8.5) for the 2080s compared to 1971-2000. The strongest increases in hydropower potential are expected for Central Africa, India, central Asia and the northern high-latitudes, with 18-33% of the world population living in these areas by the 2080s. Global mean cooling water discharge capacity is projected to decrease by 4.5-15% (2080s). The largest reductions are found for the United States, Europe, eastern Asia, and southern parts of South America, Africa and Australia, where strong water temperature increases are projected combined with reductions in mean annual streamflow. These regions are expected to affect 11-14% (for RCP2.6 and the shared socioeconomic

  13. Efficiency of preliminary discharge of stratum water in Tuymazinskoe oil field

    Science.gov (United States)

    Almukhametova, E. M.; Akimov, A. V.; Kalinina, S. V.; Fatkullin, I. F.; Gizetdinov, I. A.

    2017-10-01

    The high water content of oil is a common occurrence for many Russian fields at the late stage of development. Due to the elimination of associated water in oil, the overload of field pipelines often takes place. Products are often collected by a one-pipe system, which means that the formation water is discharged using special plants PWDS. Research workers have made it clear that the complexity of production “BashNIPIneft” and OGPD “Tuymazaneft” on Tuimazy field was due to the fact that the collection of production, in most cases, uses a centralized system, which loses its advantages when there is a large content of water in the emulsions. Research has indicated that the reagents, used in the field, proved to be ineffective, as the oil of Devonian formations is heavily saturated with paraffins. But, ultimately, the most effective agents for the destruction of emulsions have been nonetheless identified. This paper describes the implementation of the system of track discharge of formation water, which is currently in use for many oil companies not only in Russia but also worldwide.

  14. Zero Liquid Discharge (ZLD) System for Flue-Gas Derived Water From Oxy-Combustion Process

    Energy Technology Data Exchange (ETDEWEB)

    Sivaram Harendra; Danylo Oryshchyn; Thomas Ochs; Stephen J. Gerdemann; John Clark

    2011-10-16

    Researchers at the National Energy Technology Laboratory (NETL) located in Albany, Oregon, have patented a process - Integrated Pollutant Removal (IPR) that uses off-the-shelf technology to produce a sequestration ready CO{sub 2} stream from an oxy-combustion power plant. Capturing CO{sub 2} from fossil-fuel combustion generates a significant water product which can be tapped for use in the power plant and its peripherals. Water condensed in the IPR{reg_sign} process may contain fly ash particles, sodium (from pH control), and sulfur species, as well as heavy metals, cations and anions. NETL is developing a treatment approach for zero liquid discharge while maximizing available heat from IPR. Current treatment-process steps being studied are flocculation/coagulation, for removal of cations and fine particles, and reverse osmosis, for anion removal as well as for scavenging the remaining cations. After reverse osmosis process steps, thermal evaporation and crystallization steps will be carried out in order to build the whole zero liquid discharge (ZLD) system for flue-gas condensed wastewater. Gypsum is the major product from crystallization process. Fast, in-line treatment of water for re-use in IPR seems to be one practical step for minimizing water treatment requirements for CO{sub 2} capture. The results obtained from above experiments are being used to build water treatment models.

  15. Bioaccumulation Study of Produced Water Discharges from Southeastern Brazilian Offshore Petroleum Industry Using Feral Fishes.

    Science.gov (United States)

    Lourenço, Rafael André; Francioni, Eleine; da Silva, Antonio Henrique M F T; Magalhães, Caio Augusto; Gallotta, Fabiana Dias Costa; de Oliveira, Fabio Francisco; de Souza, João Maximino; de Araújo, Leandro Franco Macena; de Araújo, Liliane Pequeno; de Araújo Júnior, Marcus Antonio G; de Fátima Guadalupe Meniconi, Maria; de Souza Bindes Gomes Lopes, Monica Aparecida Ferreira

    2018-04-01

    The main effluent of oil and gas production is the discharge of produced water (PW). Despite the potential environmental impact, the structure of oil and gas platforms can act as artificial reefs. Two species of fish, Caranx crysos and Tylosurus acus, were captured under two discharging platforms at Campos Basin, P19 and P40. A nondischarging platform, P25, was taken as reference. The highest median concentration of PAH in muscle tissue was observed for C. Crysos at P40 (219.38 ng g -1 ) followed by P19 (68.26 ng g -1 ). For T. acus, the highest median concentrations were 40.07 and 42.21 ng g -1 from P19 and P40 respectively. P25 presented the smallest recorded concentrations. The results of PAH in the muscle tissue of C. crysos enabled to distinguish the platforms with PW discharge from the platform without discharge. Trace elements concentrations reflected the background levels and were not influenced by the PW release.

  16. Angina - discharge

    Science.gov (United States)

    Chest pain - discharge; Stable angina - discharge; Chronic angina - discharge; Variant angina - discharge; Angina pectoris - discharge; Accelerating angina - discharge; New-onset angina - discharge; Angina-unstable - discharge; ...

  17. Electric field measurements in nanosecond pulse discharges in air over liquid water surface

    Science.gov (United States)

    Simeni Simeni, Marien; Baratte, Edmond; Zhang, Cheng; Frederickson, Kraig; Adamovich, Igor V.

    2018-01-01

    Electric field in nanosecond pulse discharges in ambient air is measured by picosecond four-wave mixing, with absolute calibration by a known electrostatic field. The measurements are done in two geometries, (a) the discharge between two parallel cylinder electrodes placed inside quartz tubes, and (b) the discharge between a razor edge electrode and distilled water surface. In the first case, breakdown field exceeds DC breakdown threshold by approximately a factor of four, 140 ± 10 kV cm-1. In the second case, electric field is measured for both positive and negative pulse polarities, with pulse durations of ˜10 ns and ˜100 ns, respectively. In the short duration, positive polarity pulse, breakdown occurs at 85 kV cm-1, after which the electric field decreases over several ns due to charge separation in the plasma, with no field reversal detected when the applied voltage is reduced. In a long duration, negative polarity pulse, breakdown occurs at a lower electric field, 30 kV cm-1, after which the field decays over several tens of ns and reverses direction when the applied voltage is reduced at the end of the pulse. For both pulse polarities, electric field after the pulse decays on a microsecond time scale, due to residual surface charge neutralization by transport of opposite polarity charges from the plasma. Measurements 1 mm away from the discharge center plane, ˜100 μm from the water surface, show that during the voltage rise, horizontal field component (Ex ) lags in time behind the vertical component (Ey ). After breakdown, Ey is reduced to near zero and reverses direction. Further away from the water surface (≈0.9 mm), Ex is much higher compared to Ey during the entire voltage pulse. The results provide insight into air plasma kinetics and charge transport processes near plasma-liquid interface, over a wide range of time scales.

  18. Impact of oil shale mine water discharges on phytoplankton community of Purtse catchment rivers

    International Nuclear Information System (INIS)

    Raetsep, A.; Rull, E.; Liblik, V.

    2002-01-01

    The multivariate relationship between phytoplankton abundance and different factors both natural and generated by oil shale mining in the Purtse catchment rivers (Purtse, Kohtla, and Ojamaa) in Augusts 1996-2000 was studied. Impact of oil shale mine water discharges, causing the input of sulfates and chlorides into the rivers, on phytoplankton abundance in river water was characterized by significant negative linear correlation. The amount of annual precipitation influenced positively the characteristics of phytoplankton abundance in river water. The complex of linear regression formulas was derived for characterising phytoplankton abundance in the lower course of the Purtse River using meteorological, hydrological and hydrogeological as well as geochemical data of water circulation. Closing the Sompa, Tammiku and Kohtla mines in 2000-2001 decreased essentially anthropogenic stress on ecological condition of the Purtse catchment rivers. (author)

  19. Kinetic model for predicting the composition of chlorinated water discharged from power plant cooling systems

    International Nuclear Information System (INIS)

    Lietzke, M.H.

    1977-01-01

    A kinetic model for predicting the composition of chlorinated water discharged from power plant cooling systems has been developed. The model incorporates the most important chemical reactions that are known to occur when chlorine is added to natural fresh waters. The simultaneous differential equations, which describe the rates of these chemical reactions, are solved numerically to give the composition of the water as a function of time. A listing of the computer program is included, along with a description of the input variables. A worked-out example illustrates the application of the program to an actual cooling system. An appendix contains a compilation of the known equilibrium and kinetic data for many of the chemical reactions that might be encountered in chlorinating natural fresh waters

  20. Effects of water vapor on flue gas conditioning in the electric fields with corona discharge

    Energy Technology Data Exchange (ETDEWEB)

    Liqiang, QI, E-mail: qi_liqiang@163.com; Yajuan, Zhang

    2013-07-15

    Highlights: • The influence mechanism of water vapor humidification on SO{sub 2} oxidation was analyzed. •The effects of water vapor on the specific resistance in fly ash in ESPs were reported. • The effects of water vapor on the size distribution and specific surface area of fly ash were discussed. • The adhesive characteristic of fly ash in different water vapor was experimented. -- Abstract: Sulfur dioxide (SO{sub 2}) removal via pulsed discharge nonthermal plasma in the absence of ammonia was investigated to determine how electrostatic precipitators (ESPs) can effectively collect particulate matter less than 2.5 μm in diameter from flue gas. SO{sub 2} removal increased as water vapor concentration increased. In a wet-type plasma reactor, directing a gas-phase discharge plasma toward the water film surface significantly enhanced the liquid-phase oxidation of HSO{sub 3}{sup −} to SO{sub 4}{sup 2−}. Comparisons of various absorbents revealed that the hydroxyl radical is a key factor in plasma-induced liquid-phase reactions. The resistivity, size distribution, and cohesive force of fly ash at different water vapor contents were measured using a Bahco centrifuge, which is a dust electrical resistivity test instrument, as well as a cohesive force test apparatus developed by the researchers. When water vapor content increased by 5%, fly ash resistivity in flue gas decreased by approximately two orders of magnitude, adhesive force and size increased, and specific surface area decreased. Therefore, ESP efficiency increased.

  1. Analysis of experimental routines of high enthalpy steam discharge in subcooled water

    Energy Technology Data Exchange (ETDEWEB)

    Pacheco, Rafael R., E-mail: Rafael.rade@ctmsp.mar.mil.br [Centro Tecnologico da Marinha em Sao Paulo (CTMSP), SP (Brazil); Andrade, Delvonei A., E-mail: delvonei@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2015-07-01

    The discharge of high enthalpy steam through safety release valves out from pressurizers in PWR's needs to be condensed in order to allow the treatment of possibly present radwaste within. The Direct Contact Condensation is used in a relief tank to achieve the condensation. Care must be taken to avoid the bypass of the steam through the subcooled water, what would increase the peak of pressure and the necessity of structural reinforcement of the relief tank. An experiment to determine the optimal set up of the relief tank components and their characteristics (type of sprinkler, level of water, volume of tank, discharge direction, pressure in the pressurizer among others) was executed in 2000, in the CTE 150 facility, in CTMSP. In a total, 144 routines varying its components and characteristics were made, although no comprehensive analysis of its results were yet made, since the mass of data was too big to be readily analyzed. In order to comprehensively analyze it, a VBA program is being made to compile and graphically represent the mass of data. The current state of this program allowed conclusions over the peak pressure, adiabatic assumption of the experiment, and the quality of the steam generated due to the discharge. (author)

  2. Analysis of experimental routines of high enthalpy steam discharge in subcooled water

    International Nuclear Information System (INIS)

    Pacheco, Rafael R.; Andrade, Delvonei A.

    2015-01-01

    The discharge of high enthalpy steam through safety release valves out from pressurizers in PWR's needs to be condensed in order to allow the treatment of possibly present radwaste within. The Direct Contact Condensation is used in a relief tank to achieve the condensation. Care must be taken to avoid the bypass of the steam through the subcooled water, what would increase the peak of pressure and the necessity of structural reinforcement of the relief tank. An experiment to determine the optimal set up of the relief tank components and their characteristics (type of sprinkler, level of water, volume of tank, discharge direction, pressure in the pressurizer among others) was executed in 2000, in the CTE 150 facility, in CTMSP. In a total, 144 routines varying its components and characteristics were made, although no comprehensive analysis of its results were yet made, since the mass of data was too big to be readily analyzed. In order to comprehensively analyze it, a VBA program is being made to compile and graphically represent the mass of data. The current state of this program allowed conclusions over the peak pressure, adiabatic assumption of the experiment, and the quality of the steam generated due to the discharge. (author)

  3. Technical and economic aspects of purification strategies to minimise discharge water from companies with closed soilless cultivation systems

    NARCIS (Netherlands)

    Os, E.A. van; Bruins, M.; Beerling, E.; Jurgens, R.; Appelman, W.; Enthoven, N.

    2014-01-01

    The aim of the research project was to achieve closure by two complementary means: 1) maximising reuse of the nutrient solution by solving problems in recirculation that leads to discharge, and 2) purification of the left over discharged water. In this paper the technical and economic aspects of

  4. Numerical and experimental study of the pressure pulsations at the free discharge of water through the turbine

    Science.gov (United States)

    Platonov, D. V.

    2017-09-01

    The free discharge through the turbine is applied in the course of construction of hydro power plant or in case of excessive water inflow during floods or emergency situation. The experimental and numerical investigation of flow-induced pressure pulsation in hydraulic turbine draft tube at free discharge was performed.

  5. Technical and economic aspects of purification strategies to minimise discharge water from companies with closed soilless cultivation systems

    NARCIS (Netherlands)

    Os, van E.A.; Bruins, M.A.; Beerling, E.A.M.; Jurgens, R.; Appelman, W.; Enthoven, N.

    2014-01-01

    The aim of the research project was to achieve closure by two complementary means: 1) maximising reuse of the nutrient solution by solving problems in recircula-tion that leads to discharge, and 2) purification of the left over discharged water. In this paper the technical and economic aspects of

  6. Characterization of a direct dc-excited discharge in water by optical emission spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Bruggeman, Peter; Leys, Christophe [Department of Applied Physics, Ghent University, Jozef Plateaustraat 22, B-9000 Ghent (Belgium); Schram, Daan [Department of Applied Physics, Technische Universiteit Eindhoven, PO Box 513, 5600 MB Eindhoven (Netherlands); Gonzalez, Manuel A [Departamento de Fisica Aplicada, Universidad de Valladolid, 47011 Valladolid (Spain); Rego, Robby [Flemish Institute of Technological Research, VITO Materials, Boeretang 200, B-2400 Mol (Belgium); Kong, Michael G [Department of Electronic and Electrical Engineering, Loughborough University, Loughborough, Leicestershire LE11 3TU (United Kingdom)], E-mail: peter.bruggeman@ugent.be

    2009-05-01

    Dc-excited discharges generated in water at the tip of a tungsten wire which is located at the orifice of a quartz capillary are investigated by time-averaged optical emission spectroscopy. Two distinctive discharge modes are observed. For small conductivities of the liquid the discharge is a streamer-like discharge in the liquid itself (liquid mode). For conductivities above typically 45 {mu}S cm{sup -1} a large vapour bubble is formed and a streamer discharge in this vapour bubble is observed (bubble mode). Plasma temperatures and electron densities are investigated for both modes. The gas temperature is estimated from the rotational temperature of N{sub 2}(C-B) and is 1600 {+-} 200 K for the bubble mode and 1900 {+-} 200 K for the liquid mode. The rotational temperature of OH(A-X) is up to 2 times larger and cannot be used as an estimate for the gas temperature. The rotational population distribution of OH(A), {nu} = 0 is also non-Boltzmann with a large overpopulation of high rotational states. This discrepancy in rotational temperatures is discussed in detail. Electron densities are obtained from the Stark broadening of the hydrogen Balmer beta line. The electron densities in the liquid mode are of the order of 10{sup 21} m{sup -3}. In the bubble mode electron densities are significantly smaller: (3-4) x 10{sup 20} m{sup -3}. These values are compared with the Stark broadening of the hydrogen alpha and gamma lines and with electron densities obtained from current density measurements. The chemical reactivities of the bubble and liquid modes are compared by means of the hydrogen peroxide production rate.

  7. Characterization of a direct dc-excited discharge in water by optical emission spectroscopy

    International Nuclear Information System (INIS)

    Bruggeman, Peter; Leys, Christophe; Schram, Daan; Gonzalez, Manuel A; Rego, Robby; Kong, Michael G

    2009-01-01

    Dc-excited discharges generated in water at the tip of a tungsten wire which is located at the orifice of a quartz capillary are investigated by time-averaged optical emission spectroscopy. Two distinctive discharge modes are observed. For small conductivities of the liquid the discharge is a streamer-like discharge in the liquid itself (liquid mode). For conductivities above typically 45 μS cm -1 a large vapour bubble is formed and a streamer discharge in this vapour bubble is observed (bubble mode). Plasma temperatures and electron densities are investigated for both modes. The gas temperature is estimated from the rotational temperature of N 2 (C-B) and is 1600 ± 200 K for the bubble mode and 1900 ± 200 K for the liquid mode. The rotational temperature of OH(A-X) is up to 2 times larger and cannot be used as an estimate for the gas temperature. The rotational population distribution of OH(A), ν = 0 is also non-Boltzmann with a large overpopulation of high rotational states. This discrepancy in rotational temperatures is discussed in detail. Electron densities are obtained from the Stark broadening of the hydrogen Balmer beta line. The electron densities in the liquid mode are of the order of 10 21 m -3 . In the bubble mode electron densities are significantly smaller: (3-4) x 10 20 m -3 . These values are compared with the Stark broadening of the hydrogen alpha and gamma lines and with electron densities obtained from current density measurements. The chemical reactivities of the bubble and liquid modes are compared by means of the hydrogen peroxide production rate.

  8. Effects of water vapor on flue gas conditioning in the electric fields with corona discharge.

    Science.gov (United States)

    Liqiang, Qi; Yajuan, Zhang

    2013-07-15

    Sulfur dioxide (SO2) removal via pulsed discharge nonthermal plasma in the absence of ammonia was investigated to determine how electrostatic precipitators (ESPs) can effectively collect particulate matter less than 2.5μm in diameter from flue gas. SO2 removal increased as water vapor concentration increased. In a wet-type plasma reactor, directing a gas-phase discharge plasma toward the water film surface significantly enhanced the liquid-phase oxidation of HSO3(-) to SO4(2-). Comparisons of various absorbents revealed that the hydroxyl radical is a key factor in plasma-induced liquid-phase reactions. The resistivity, size distribution, and cohesive force of fly ash at different water vapor contents were measured using a Bahco centrifuge, which is a dust electrical resistivity test instrument, as well as a cohesive force test apparatus developed by the researchers. When water vapor content increased by 5%, fly ash resistivity in flue gas decreased by approximately two orders of magnitude, adhesive force and size increased, and specific surface area decreased. Therefore, ESP efficiency increased. Copyright © 2013 Elsevier B.V. All rights reserved.

  9. Influence Voltage Pulse Electrical Discharge In The Water at the Endurance Fatigue Of Carbon Steel

    Directory of Open Access Journals (Sweden)

    I.A. Vakulenko

    2016-05-01

    Full Text Available Effect of pulses of electrical discharge in the water at the magnitude of the limited endurance under cyclic loading thermally hardened carbon steel was investigated. Observed increase stamina during cyclic loading a corresponding increase in the number of accumulated dislocations on the fracture surface. Using the equation of Cofino-Manson has revealed a decrease of strain loading cycle after treatment discharges. For field-cycle fatigue as a result of processing the voltage pulses carbon steel structure improvement, followed by growth of limited endurance decrease per cycle of deformation. With increasing amplitude of the voltage loop gain stamina effect on metal processing voltage pulses is reduced. The results can be used to extend the life of parts that are subject to cyclic loading.

  10. [Mechanism of the organic pollutant degradation in water by hybrid gas-liquid electrical discharge].

    Science.gov (United States)

    Zhu, Li-nan; Ma, Jun; Yang, Shi-dong

    2007-09-01

    The method of hybrid gas-liquid electrical discharge was investigated for the removal of phenol. The results indicate that this new method can remove phenol in water effectively. The removal rate increases with increasing voltage and air aeration. The production quantity of H2O2 and O3 is measured respectively in the discharge region and the production quantity increases with increasing of voltage and air aeration. The energy consumption analysis indicates that with increasing the voltage, the increase extent of the phenol removal rate is smaller than the energy's, so the increase of energy efficiency is very small. Air aeration increases the energy consumption. At the same time, a considerable part of energy in the overall input energy makes the temperature of the solution increase, and more energy is transformed into heat, which leads to the waste of energy.

  11. A Review on overboard CEOR discharged produced water treatment and remediation

    Science.gov (United States)

    Rawindran, H.; Krishnan, S.; Sinnathambi, C. M.

    2017-06-01

    Produced water is a waste by-product generated during oil and gas recovery operations. It contains the mixture of organic and inorganic compounds. Produced water management is a challenge faced by the petroleum practitioners worldwide. Build-up of chemical wastes from produced water causes huge footprint, which results in high CapEx and OpEx. Different technologies are practiced by various practitioners to treat the produced waste water. However, the constituents removed by each technology and the degree of organic compound removal has to be considered to identify the potential and effective treatment technologies for offshore industrial applications. Current produced water technologies and their successful applications have advantages and disadvantages and can be ranked on the basis of several factors, such as their discharge limit into water bodies, reinjection in producing well, or for any miscellaneous beneficial use. This paper attempts to provide a review of existing physical and chemical treatment technologies used for management of produced water. Based on our analysis, suitable methods will be recommended for offshore waste water treatment technologies.

  12. Prevenção de cárie dentária por bochechos com flúor em município com água fluoretada Fluoride mouth-rinsing to prevent dental caries in a Brazilian municipality with fluoridated drinking water

    Directory of Open Access Journals (Sweden)

    Maria Luiza Hiromi Iwakura

    2004-04-01

    Full Text Available OBJETIVO: Comparar a prevalência de cárie dentária em escolares que participaram de um programa semanal de bochecho com fluoreto de sódio a 0,2% com a prevalência de cárie em escolares que não participaram do programa. MÉTODOS: Estudo transversal na Cidade de Londrina, Estado do Paraná, Brasil, cuja população consome água fluoretada. Foram examinados 367 escolares de 12 anos: 190 participantes (51,8% e 177 não participantes (48,2% do programa semanal de bochecho. Os índices utilizados foram o de dentes cariados, perdidos e obturados e o de superfícies cariadas, perdidas e obturadas. Os exames foram conduzidos por três examinadores e a concordância no diagnóstico de cárie foi quase perfeita (K = 0,90. A cárie dentária foi considerada variável dependente. As variáveis independentes foram: a participação ou não no programa, estudar em escola pública ou privada, escovação dentária, quantidade de dentifrício utilizada, ingestão de doces e consulta ao dentista. RESULTADOS: O índice de dentes cariados, perdidos e obturados aos 12 anos foi 0,85 ± 0,059 (0,70 ±0,060 para não participantes e 1,0 ±0,058 para participantes. O índice de superfícies cariadas, perdidas e obturadas foi 1,16 ±0,017, variando de 0,34 a 1,66. Na análise bivariada, estiveram estatisticamente associados (P OBJECTIVE: To compare the prevalence of dental caries in two groups of schoolchildren: (1 schoolchildren participating in a weekly 0.2% sodium fluoride mouth-rinsing program and (2 schoolchildren not participating in the program. METHODS: This cross-sectional study was conducted in the city (municipality of Londrina, in the state of Paraná, Brazil; the city has fluoridated drinking water. We examined 367 12-year-old children: 190 participants in the weekly mouth-rinsing program (51.8% and 177 nonparticipants (48.2%. The prevalence of caries was determined based on the scores for decayed, missing, and filled teeth and for decayed, missing

  13. Effects of pulse frequency of input power on the physical and chemical properties of pulsed streamer discharge plasmas in water

    Science.gov (United States)

    Ruma; Lukes, P.; Aoki, N.; Spetlikova, E.; Hosseini, S. H. R.; Sakugawa, T.; Akiyama, H.

    2013-03-01

    A repetitive pulsed-power modulator, which employs a magnetic pulse compression circuit with a high-speed thyristor switch, was used to study the effects of the pulse repetition rate of input power on the physical and chemical properties of pulsed discharges in water. Positive high-voltage pulses of 20 kV with repetition rates of up to 1 kHz were used to generate a discharge in water using the point-to-plane electrode geometry. By varying the pulse repetition rate, two distinct modes of the discharge plasma were formed in water. The first mode was characterized by the formation of a corona-like discharge propagating through water in the form of streamer channels. The second mode was formed typically above 500 Hz, when the formation of streamer channels in water was suppressed and all plasmas occurred inside a spheroidal aggregate of very fine gas bubbles surrounding the tip of the high-voltage electrode. The production of hydrogen peroxide, degradation of organic dye Acid Orange 7 (AO7) and inactivation of bacteria Escherichia coli by the discharge in water were studied under different discharge plasma modes in dependence on the pulse repetition rate of input power. The efficiency of both chemical and biocidal processes induced by the plasma in water decreased significantly with pulse repetition rates above 500 Hz.

  14. Effects of pulse frequency of input power on the physical and chemical properties of pulsed streamer discharge plasmas in water

    International Nuclear Information System (INIS)

    Ruma; Aoki, N; Hosseini, S H R; Sakugawa, T; Akiyama, H; Lukes, P; Spetlikova, E

    2013-01-01

    A repetitive pulsed-power modulator, which employs a magnetic pulse compression circuit with a high-speed thyristor switch, was used to study the effects of the pulse repetition rate of input power on the physical and chemical properties of pulsed discharges in water. Positive high-voltage pulses of 20 kV with repetition rates of up to 1 kHz were used to generate a discharge in water using the point-to-plane electrode geometry. By varying the pulse repetition rate, two distinct modes of the discharge plasma were formed in water. The first mode was characterized by the formation of a corona-like discharge propagating through water in the form of streamer channels. The second mode was formed typically above 500 Hz, when the formation of streamer channels in water was suppressed and all plasmas occurred inside a spheroidal aggregate of very fine gas bubbles surrounding the tip of the high-voltage electrode. The production of hydrogen peroxide, degradation of organic dye Acid Orange 7 (AO7) and inactivation of bacteria Escherichia coli by the discharge in water were studied under different discharge plasma modes in dependence on the pulse repetition rate of input power. The efficiency of both chemical and biocidal processes induced by the plasma in water decreased significantly with pulse repetition rates above 500 Hz. (paper)

  15. Evaluation of the depth-integration method of measuring water discharge in large rivers

    Science.gov (United States)

    Moody, J.A.; Troutman, B.M.

    1992-01-01

    The depth-integration method oor measuring water discharge makes a continuos measurement of the water velocity from the water surface to the bottom at 20 to 40 locations or verticals across a river. It is especially practical for large rivers where river traffic makes it impractical to use boats attached to taglines strung across the river or to use current meters suspended from bridges. This method has the additional advantage over the standard two- and eight-tenths method in that a discharge-weighted suspended-sediment sample can be collected at the same time. When this method is used in large rivers such as the Missouri, Mississippi and Ohio, a microwave navigation system is used to determine the ship's position at each vertical sampling location across the river, and to make accurate velocity corrections to compensate for shift drift. An essential feature is a hydraulic winch that can lower and raise the current meter at a constant transit velocity so that the velocities at all depths are measured for equal lengths of time. Field calibration measurements show that: (1) the mean velocity measured on the upcast (bottom to surface) is within 1% of the standard mean velocity determined by 9-11 point measurements; (2) if the transit velocity is less than 25% of the mean velocity, then average error in the mean velocity is 4% or less. The major source of bias error is a result of mounting the current meter above a sounding weight and sometimes above a suspended-sediment sampling bottle, which prevents measurement of the velocity all the way to the bottom. The measured mean velocity is slightly larger than the true mean velocity. This bias error in the discharge is largest in shallow water (approximately 8% for the Missouri River at Hermann, MO, where the mean depth was 4.3 m) and smallest in deeper water (approximately 3% for the Mississippi River at Vickbsurg, MS, where the mean depth was 14.5 m). The major source of random error in the discharge is the natural

  16. Does zero-water discharged technology enhance culture performance of pacific white shrimp (Litopenaeus vannamei Boone.)?

    Science.gov (United States)

    Suantika, Gede; Anggraeni, Jayanty; Hasby, Fahri Azhari; Yanuwiarti, Ni Putu Indah

    2014-03-01

    Litopenaeus vannamei or white leg shrimp is an introduced shrimp which has successfully cultured in Indonesia. In Indonesia, L. vannamei is commonly cultured on outdoor/earthen pond that requires renewal of water, less control in term of water quality and disease and attributed to unpredictable yield production. Based on the existing culture condition, a system that enable to minimize water consumption, improve the hygiene of the culture and at the same time maintain a more stable yield production is urgent to be developed by using a zero water discharge system. The system consists of: (a) culture tank - to retain and culture the shrimp; (b) CaCO3 grained - buffering agent and substrate of nitrifying bacteria; (c) aeration line - to provide O2 and homogenize the culture; (d) ancho (feeding) - to control an appropriate feed; (e) nitrifying bacteria adding - to consume ammonium and nitrite then convert it to nitrate, and also control pathogen Vibrio sp.; (f) diatom microalgae (Chaetoceros gracilis) - to uptake nitrate, bacteriostatic agent, feed source, provide O2 and shading. In this study, there were 2 treatments: the static culture (batch) system was set as control (K) (in 70 PL/m2), and culture system with zero-water discharge system which was inoculated by 0.02% v/v 106 CFU/ml of mixed culture nitrifying bacteria and diatom microalgae in 70 PL/m2 (P1). The white leg shrimp used in this experiment was at post larvae (PL) 10 and cultured in a batch system (1 × 1 × 0.5 m3 pond) during 2 months. Several parameters including survival rate, mean body weight, and water quality (salinity, temperature, pH, DO, ammonium, nitrite, and nitrate) were measured. Based on the results, biomass of P1 (237.12 ± 31.11) gram is significantly higher than control (K) (180.80 ± 12.26) gram (Pshrimp post larvae, except ammonium concentration in control (K) (2.612 ± 0.56) mg/L which is significantly different from P1 (1.287 ± 0.49) mg/L. Based on this research, zero-water discharge

  17. Effects of Hydroxyl Radicals on Introduced Organisms of Ship's Ballast Water Based Micro-Gap Discharge

    International Nuclear Information System (INIS)

    Bai Mindong; Zhang Zhitao; Bai Mindi; Yang Bo; Bai Xiyao

    2007-01-01

    With the physical method of micro-gap gas discharge, OH· radicals were produced by the ionization of O 2 in air and H 2 O in the gaseous state, in order to explore more effective method to treat the ship's ballast water. The surface morphology of Al 2 O 3 dielectric layer was analysed using Atomic Force Microscopy (AFM), where the size of Al 2 O 3 particles was in the range of 2 μm to 5 μm. At the same time, the biochemical effect of hydroxyl radicals on the introduced organisms and the quality of ship's ballast water were studied. The results indicate that the main reasons of cell death are lipid peroxide and damage of the antioxidant enzyme system in Catalase (CAT), Peroxidase (POD) and Superoxide dismutase (SOD). In addition, the quality of the ballast water was greatly improved

  18. Contaminant transport modelling in tidal influenced water body for low level liquid waste discharge out

    International Nuclear Information System (INIS)

    Singh, Sanjay; Naidu, Velamala Simhadri

    2018-01-01

    Low level liquid waste is generated from nuclear reactor operation and reprocessing of spent fuel. This waste is discharged into the water body after removing bulk of its radioactivity. Dispersion of contaminant mainly depends on location of outfall and hydrodynamics of water body. For radiological impact assessment, in most of the analytical formulations, source term is taken as continuous release. However, this may not be always true as the water level is influenced by tidal movement and the selected outfall may come under intertidal zone in due course of the tidal cycle. To understand these phenomena, a case study has been carried out to evaluate hydrodynamic characteristics and dilution potential of outfall located in inter-tidal zone using numerical modelling

  19. Global land–ocean linkage: direct inputs of nitrogen to coastal waters via submarine groundwater discharge

    International Nuclear Information System (INIS)

    Beusen, A H W; Slomp, C P; Bouwman, A F

    2013-01-01

    The role of submarine groundwater discharge (SGD), the leakage of groundwater from aquifers into coastal waters, in coastal eutrophication has been demonstrated mostly for the North American and European coastlines, but poorly quantified in other regions. Here, we present the first spatially explicit global estimates of N inputs via SGD to coastal waters and show that it has increased from about 1.0 to 1.4 Tg of nitrate (NO 3 -N) per year over the second half of the 20th century. Since this increase is not accompanied by an equivalent increase of groundwater phosphorus (P) and silicon (Si), SGD transport of nitrate is an important factor for the development of harmful algal blooms in coastal waters. Groundwater fluxes of N are linked to areas with high runoff and intensive anthropogenic activity on land, with Southeast Asia, parts of North and Central America, and Europe being hot spots. (letter)

  20. Measurements of water molecule density by tunable diode laser absorption spectroscopy in dielectric barrier discharges with gas-water interface

    Science.gov (United States)

    Tachibana, Kunihide; Nakamura, Toshihiro; Kawasaki, Mitsuo; Morita, Tatsuo; Umekawa, Toyofumi; Kawasaki, Masahiro

    2018-01-01

    We measured water molecule (H2O) density by tunable diode-laser absorption spectroscopy (TDLAS) for applications in dielectric barrier discharges (DBDs) with a gas-water interface. First, the effects of water temperature and presence of gas flow were tested using a Petri dish filled with water and a gas injection nozzle. Second, the TDLAS system was applied to the measurements of H2O density in two types of DBDs; one was a normal (non-inverted) type with a dielectric-covered electrode above a water-filled counter electrode and the other was an inverted type with a water-suspending mesh electrode above a dielectric-covered counter electrode. The H2O density in the normal DBD was close to the density estimated from the saturated vapor pressure, whereas the density in the inverted DBD was about half of that in the former type. The difference is attributed to the upward gas flow in the latter type, that pushes the water molecules up towards the gas-water interface.

  1. A model for water discharge based on energy consumption data (WATEN).

    Science.gov (United States)

    Moyano, María Carmen; Tornos, Lucía; Juana, Luis

    2014-05-01

    As the need for water conservation is becoming a major water concern, a lumped model entitled WATEN has been proposed to analyse the water balance in the B-XII Irrigation Sector of the Lower Guadalquivir Irrigated Area, one of the largest irrigated areas in Spain. The aim of this work is to approach the hydrological study of an irrigation district lacking of robust data in such a manner that the water balance is performed from less to more process complexity. WATEN parameters are the total and readily available moisture in the soil, a fix percentage for effective precipitation, and the irrigation efficiency. The Sector presents six different drainage pumping stations, with particular pumping groups and with no water flow measurement devices. Energy consumption depends on the working pumping stations and groups, and on the variable water level to discharge. Energy consumed in the drainage pumping stations has been used for calibration The study has relied on two monthly series of data: the volume of drainage obtained from the model and the energy consumed in the pumping stations. A double mass analysis has permitted the detection of data tendencies. The two resulting series of data have been compared to assess model performance, particularly the Pearson's product moment correlation coefficient and the Nash-Sutcliffe coefficient of efficiency, e2, determined for monthly data and for annual and monthly average data. For model calibration, we have followed a classical approach based on objective functions optimization, and a robust approach based on Markov chain Monte Carlo simulation process, driven in a similar manner to genetic algorithms, entitled Parameters Estimation on Driven Trials (PEDT), and aiming to reduce computational requirements. WATEN has been parameterised maintaining its physical and conceptual rationality. The study approach is outlined as a progressive introduction of data. In this manner, we can observe its effect on the studied objective

  2. Long-Term Temporal Variability of the Freshwater Discharge and Water Levels at Patos Lagoon, Rio Grande do Sul, Brazil

    Directory of Open Access Journals (Sweden)

    G. P. Barros

    2012-01-01

    Full Text Available The aim of this study is to investigate the importance of freshwater discharge as a physical forcing in Patos Lagoon at timescales longer than one year, as well as identify the temporal variability of the dominant processes in freshwater discharge and water levels along the Patos Lagoon. Due to its proximity to the mouth, the water level at the estuary is influenced by the remote effects associated with the adjacent ocean circulation and wave climatology, reducing the observed correlation. At the lagoonar region a high correlation is expected because interannual data is being used, reducing the influence of the wind. Cross wavelet technique is applied to examine the coherence and phase between interannual time-series (South Oscillation Index, freshwater discharge and water levels. The freshwater discharge of the main tributaries and water levels in Patos Lagoon are influenced by ENSO on interannual scales (cycles between 3.8 and 6 years. Therefore, El Niño events are associated with high mean values of freshwater discharge and water levels above the mean. On the other hand, La Niña events are associated with low mean values of freshwater discharge and water levels below the mean.

  3. Collapse of a cavitation bubble generated by low voltage discharge in water

    Directory of Open Access Journals (Sweden)

    Zima Patrik

    2012-04-01

    Full Text Available The article presents experimental results of the optical study of cavitation bubble collapse close to a solid boundary in water. The bubble was generated by discharge of two low-voltage capacitors. High-speed CCD camera was used to record the time evolution of the bubble size. High-power halogen lamp was used for illumination. The system was synchronized by pulse generator connected to an oscilloscope. The velocity of the re-entrant jet was estimated from the time resolved photography for different maximum bubble sizes.

  4. Waste Field Characteristics, Ultimate Mixing and Dilution in Surface Discharge of Dense Jets into Stagnant Water Bodies

    Directory of Open Access Journals (Sweden)

    2012-04-01

    Full Text Available Direct discharges of municipal and industrial waste waters into water bodies through marine outfalls are considered as a common way to dispose the generated waste in coastal zones. Marine discharge, intensifying flow mixing and entrainment, decrease the concentration of polutant up to accepted concentration and meet the guideline values and to make possible continues discharge of flow into matine environment. During last years due to quick development of coastal desalination plants, surface discharge of preduced salty water into seas and oceans has increased significantly. In this study, releases of dense jets from surface rectangular channel into stagnant bodies are experimentally studied. The location of flow plunge point, impact point and discharge ultimate dilution were drown out by a digital video technology. In addition, using some conductivity probes located in ambient floor, waste filed dilution in flow impact point and discharge ultimate dilution were identified. Finally the obtained results were plotted and explained along with some diagrams to show flow non-dimensional behavior. The results showed that the properties of flow are changing directly with ambient water depth and discharge initial fluxes.

  5. Purification of water by bipolar pulsed discharge plasma combined with TiO2 catalysis

    International Nuclear Information System (INIS)

    Zhang, Yongrui; Ma, Wenchang; Zhang, Xian; Wang, Liming; Zhang, Ruobing; Guan, Zhicheng

    2013-01-01

    In the process of water treatment by bipolar pulsed discharge plasma, there are not only the chemical effects such as the cold plasma, but also the physical effects such as the optical radiation. The energy of the optical radiation can be used by photocatalyst. Therefore, the effect of the photocatalyst to the degradation of the organic pollutant was investigated using a packed bed reactor by bipolar pulsed discharge in the air-liquid-solid mixture. The nanoparticle TiO 2 photocatalyst was obtained using the sol-gel method and the typical dye solution Indigo Carmine was chosen as the degradation target to test the catalytic effect of the nanoparticle TiO 2 photocatalyst. Experiment results proved that the degradation efficiency of the Indigo Carmine solution was increased by a certain extent with the TiO 2 photocatalyst. It was totally decolorized within 3 minutes by bipolar pulsed discharge in the condition that the peak voltage was 30 kV and the air flow was 1.0 m 3 h −1 .

  6. The effect of purified sewage discharge from a sewage treatment plant on the physicochemical state of water in the receiver

    Directory of Open Access Journals (Sweden)

    Kanownik Włodzimierz

    2016-09-01

    Full Text Available The paper presents changes in the contents of physicochemical indices of the Sudół stream water caused by a discharge of purified municipal sewage from a small mechanical-biological treatment plant with throughput of 300 m3·d−1 and a population equivalent (p.e. – 1,250 people. The discharge of purified sewage caused a worsening of the stream water quality. Most of the studied indices values increased in water below the treatment plant. Almost a 100-fold increase in ammonium nitrogen, 17-fold increase in phosphate concentrations and 12-fold raise in BOD5 concentrations were registered. Due to high values of these indices, the water physicochemical state was below good. Statistical analysis revealed a considerable effect of the purified sewage discharge on the stream water physicochemical state. A statistically significant increase in 10 indices values (BOD5, COD-Mn, EC, TDS, Cl−, Na+, K+, PO43−, N-NH4+ and N-NO2 as well as significant decline in the degree of water saturation with oxygen were noted below the sewage treatment plant. On the other hand, no statistically significant differences between the water indices values were registered between the measurement points localised 150 and 1,000 m below the purified sewage discharge. It evidences a slow process of the stream water self-purification caused by an excessive loading with pollutants originating from the purified sewage discharge.

  7. Analytical approach for predicting fresh water discharge in an estuary based on tidal water level observations

    NARCIS (Netherlands)

    Cai, H.; Savenije, H.H.G.; Jiang, C.

    2014-01-01

    As the tidal wave propagates into an estuary, the tidally averaged water level tends to rise in landward direction due to the density difference between saline and fresh water and the asymmetry of the friction. The effect of friction on the residual slope is even more remarkable when accounting for

  8. Electrochemical reactor with rotating cylinder electrode for optimum electrochemical recovery of nickel from plating rinsing effluents

    Energy Technology Data Exchange (ETDEWEB)

    Hernández-Tapia, J.R.; Vazquez-Arenas, J., E-mail: jgva@xanum.uam.mx; González, I.

    2013-11-15

    Highlights: • Rotating cylinder cathode enhanced mass transport rates of Ni(II) species. • pH control around 4 is crucial to recover high purity nickel. • Increasing cathodic currents increased energy consumptions for nickel recovery. • Specific energy consumptions increase drastically at the end of electrolysis. -- Abstract: This study is devoted to analyze the metallic electrochemical recovery of nickel from synthetic solutions simulating plating rinsing discharges, in order to meet the water recycling policies implemented in these industries. These effluents present dilute Ni(II) concentrations (100 and 200 ppm) in chloride and sulfate media without supporting electrolyte (397–4202 μS cm{sup −1}), which stems poor current distribution, limited mass transfer, ohmic drops and enhancement of parasitic reactions. An electrochemical reactor with rotating cylinder electrode (RCE) and a pH controller were utilized to overcome these problems. The pH control around 4 was crucial to yield high purity nickel, and thus prevent the precipitation of hydroxides and oxides. Macroelectrolysis experiments were systematically conducted to analyze the impacts of the applied current density in the recovery efficiency and energy consumption, particularly for very diluted effluents (100 and 200 ppm Ni(II)), which present major recovery problems. Promising nickel recoveries in the order of 90% were found in the former baths using a current density of −3.08 mA cm{sup −2}, and with overall profits of 9.64 and 14.69 USD kg{sup −1}, respectively. These estimations were based on the international market price for nickel ($18 USD kg{sup −1})

  9. Nanofiltration of Mine Water: Impact of Feed pH and Membrane Charge on Resource Recovery and Water Discharge

    Directory of Open Access Journals (Sweden)

    Mark Mullett

    2014-03-01

    Full Text Available Two nanofiltration membranes, a Dow NF 270 polyamide thin film and a TriSep TS 80 polyamide thin film, were investigated for their retention of ionic species when filtering mine influenced water streams at a range of acidic pH values. The functional iso-electric point of the membranes, characterized by changes in retention over a small pH range, were examined by filtering solutions of sodium sulphate. Both membranes showed changes in retention at pH 3, suggesting a zero net charge on the membranes at this pH. Copper mine drainage and synthetic solutions of mine influenced water were filtered using the same membranes. These solutions were characterized by pH values within 2 and 5, thus crossing the iso-electric point of both membranes. Retention of cations was maximized when the feed solution pH was less than the iso-electric point of the membrane. In these conditions, the membrane has a net positive charge, reducing the transmission rate of cations. From the recoveries of a range of cations, the suitability of nanofiltration was discussed relative to the compliance with mine water discharge criteria and the recovery of valuable commodity metals. The nanofiltration process was demonstrated to offer advantages in metal recovery from mine waste streams, concomitantly enabling discharge criteria for the filtrate disposal to be met.

  10. Locating Ground-Water Discharge in the Hanford Reach of the Columbia River

    International Nuclear Information System (INIS)

    Lee, D.R.; Geist, D.R.; Saldi, K.; Hartwig, D.; Cooper, T.

    1997-01-01

    A bottom-contacting probe for measuring electrical conductivity at the sediment-water interface was used to scan the bed of the Columbia River adjacent to the Hanford Site in southeast Washington State during a 10-day investigation. Four river-sections, each about a kilometer in length, were scanned for variations in electrical conductivity. The probe was towed along the riverbed at a speed of 1 m/s and is position was recorded using a Global Positioning System. The bottom tows revealed several areas of elevated electrical conductivity. Where these anomalies were relatively easy to access, piezometers were driven into the riverbed and porewater electrical conductivity ranged from 111 to 150 uS/cm. The piezometers, placed in electrical conductivity ''hotspots'' yielded chemical or isotopic data consistent with previous analyses of water taken from monitoring wells and visible shoreline seeps. Tritium, nitrate, and chromium exceeded water quality standards in some porewaters. The highest tritium and nitrate levels were found near the Old Hanford Townsite at 120,000 pCi/L (+ 5,880 pCi/L total propagated analytical uncertainty) and ug/L (+ 5,880 ug/L), respectively. The maximum chromium (total and hexavalent) levels were found near 100-H reactor area where unfiltered porewater total chromium was 1,900 ug/L (+ 798 ug/L) and hexavalent chromium was 20 ug/L. The electrical conductivity probe provided rapid, cost-effective reconnaissance for ground-water discharge areas when used in combination with conventional piezometers. It may be possible to obtain quantitative estimates of both natural and contaminated ground-water discharge in the Hanford Reach with more extensive surveys of river bottom

  11. Effects of thermal discharges on the seasonal patterns of nutrient concentrations in brackish water

    International Nuclear Information System (INIS)

    Nitchals, D.

    1985-05-01

    Massiv quantities of water are used in power plant cooling systems, especially nuclear power plants, and are often returned to the donor ecosystem at significantly elevated temperatures. Few studies of the environmental effects of such a situation have looked extensively at the effects on nutrients in the water. The present study examined the effects of cooling water discharges from a nuclear power plant on the seasonal nutrient patterns within and outside a brackish water, research artificial lake, the 0.9 km 2 Biotest Basin on Sweden's east coast. The lack of ice cover in winter is the most apparent effect. In a portion of the lake with a relatively long water residence time, on the order of a few days, the vernal nutrient depletion of phosphate, nitrate, and nitrite apparently began sooner than outside the lake. Benthic influence on nutrient concentrations in the free water mass may be very significant in coastal areas receiving heat inputs. This study's data apparently support the conclusion by other researchers that phosphorus may be the nutrient limiting algal growth in the spring in this area of the central Baltic Sea. Determination of a nutrient budget for the Basin was unachievable because inlet and outlet nutrient concentrations were insufficiently different to override experimental variation. Implications for management of heat inputs to coastal ecosystems include avoidance of areas with high nutrient content, rich organic sediment, or poor flushing. (author)

  12. Characteristics of Rainfall-Discharge and Water Quality at Limboto Lake, Gorontalo, Indonesia

    Directory of Open Access Journals (Sweden)

    Luki Subehi

    2016-08-01

    Full Text Available Problems of high turbidity, sedimentation, water pollution and siltation occur at Limboto Lake, Gorontalo, Indonesia. The objective of this study was to analyze the rainfall-discharge relationship and its implications for water quality conditions. Secchi disk (water transparency, chlorophyll-a (chl-a, and total organic matter (TOM were measured in May 2012, September 2012 and March 2013 at three sites of the lake (L-1, L-2 and L-3 to observe the impacts on the surrounding catchment. Based on representative stations for rainfall data from 2004 to 2013, monthly averages of rainfall in March-May (166.7 mm and September (76.4 mm were used to represent the wet and dry period, respectively. Moreover, sediment traps at these three sites were installed in September 2012. Based on the analysis it is suggested that rainfall magnitude and land use change at the Alopohu River catchment influenced the amount of materials flowing into the lake, degrading the water quality. Specifically, the higher average rainfall in May (184.5 mm gave a higher average total sediment load (4.41 g/L/day. In addition, water transparency decreased with increasing chl-a. This indicates that the concentrations of sediment and nutrients, reflected by the high amount of chl-a, influenced the water quality conditions.

  13. Relationship of a turbidity of an oral rinse with oral health and malodor in Vietnamese patients.

    Science.gov (United States)

    Pham, Thuy A V

    2014-05-01

    In the present study, the relationship between the turbidity of mouth-rinse water and oral health conditions, including oral malodor, in patients with (n = 148) and without (n = 231) periodontitis was examined. The turbidity of 20 mL distilled water that the patients rinsed in their mouths 10 times was measured using a turbidimeter. Oral malodor was evaluated using an organoleptic test and Oral Chroma. Oral health conditions, including decayed teeth, periodontal status, oral hygiene status, proteolytic activity of the N-benzoyl-dl-arginine-2-napthilamide (BANA) test on the tongue coating, and salivary flow rate, were assessed. Turbidity showed significant correlations with oral malodor and all oral health parameters in the periodontitis group. In the non-periodontitis group, turbidity showed significant correlations with oral malodor and oral health parameters, including dental plaque, tongue coating, BANA test, and salivary flow rate. The regression analysis indicated that turbidity was significantly associated with methyl mercaptan and the BANA test in the periodontitis group, and with hydrogen sulfide, dental plaque, tongue coating, and salivary flow rate in the non-periodontitis group. The findings of the present study indicate that the turbidity of mouth-rinse water could be used as an indicator of oral health conditions, including oral malodor. © 2013 Wiley Publishing Asia Pty Ltd.

  14. The predicted impacts to the groundwater and Columbia River from ammoniated water discharges to the 216-A-36B crib

    International Nuclear Information System (INIS)

    Buelt, J.L.; Conbere, W.; Freshley, M.D.; Hicks, R.J.; Kuhn, W.L.; Lamar, D.A.; Serne, R.J.; Smoot, J.L.

    1988-03-01

    Impact from past and potential future discharges of ammoniated water to the 216-A-36B crib have on groundwater and river concentrations of hazardous chemical constitutents are studied. Until August 1987, the 216-A-36B crib, located in the 200-East Area of the Hanford Site, accepted ammoniated water discharges. Although this study addresses known hazardous chemical constituents associated with such discharges, the primary concern is the discharge of NH 4 OH because of its microbiological conversion to NO 2 /sup /minus// and NO 3 /sup /minus//. As a result of fuel decladding operations, material balance calculations indicate that NH 4 OH has been discharged to the 216-A-36B crib in amounts that exceed reportable quantities under the Comprehensive Environmental Response, Compensation and Liability Act of 1980. Although flow to the crib is relatively constant, the estimated NH 4 OH discharge varies from negligible to a maximum of 10,000 g-molesh. Because these discharges are intermittent, the concentration delivered to the groundwater is a function of soil sorption, microbiological conversion rates of NH 4 + to NO 2 /sup /minus// and NO 3 /sup /minus//, and groundwater dispersion. This report provides results based on the assumptions of maximum, nominal, and discountinued NH 4 OH discharges to the crib. Consequently, the results show maximum and realistic estimates of NH 4 + , NO 2 /sup /minus// and NO 3 /sup /minus// concentrations in the groundwater

  15. Phosphonate removal from discharged circulating cooling water using iron-carbon micro-electrolysis.

    Science.gov (United States)

    Zhou, Zhen; Qiao, Weimin; Lin, Yangbo; Shen, Xuelian; Hu, Dalong; Zhang, Jianqiao; Jiang, Lu-Man; Wang, Luochun

    2014-01-01

    Phosphonate is a commonly used corrosion and scale inhibitor for a circulating cooling water (CCW) system. Its discharge could cause eutrophication of receiving waters. The iron-carbon (Fe/C) micro-electrolysis technology was used to degrade and remove phosphonate from discharged CCW. The influences of initial pH, Fe/C ratio (FCR) and temperature on phosphonate removal were investigated in a series of batch tests and optimized by response surface methodology. The quadratic model of phosphonate removal was obtained with satisfactory degrees of fitness. The optimum conditions with total phosphorus removal efficiency of 95% were obtained at pH 7.0, FCR of 1.25, and temperature of 45 °C. The phosphonate removal mechanisms were also studied. Phosphonate removal occurred predominantly via two consecutive reactive phases: the degradation of phosphonate complexes (Ca-phosphonate) and the precipitation of Fe/C micro-electrolysis products (PO₄(3-), Ca²⁺ and Fe³⁺).

  16. Dielectric Barrier Discharge based Mercury-free plasma UV-lamp for efficient water disinfection.

    Science.gov (United States)

    Prakash, Ram; Hossain, Afaque M; Pal, U N; Kumar, N; Khairnar, K; Mohan, M Krishna

    2017-12-12

    A structurally simple dielectric barrier discharge based mercury-free plasma UV-light source has been developed for efficient water disinfection. The source comprises of a dielectric barrier discharge arrangement between two co-axial quartz tubes with an optimized gas gap. The outer electrode is an aluminium baked foil tape arranged in a helical form with optimized pitch, while the inner electrode is a hollow aluminium metallic rod, hermetically sealed. Strong bands peaking at wavelengths 172 nm and 253 nm, along with a weak band peaking at wavelength 265 nm have been simultaneously observed due to plasma radiation from the admixture of xenon and iodine gases. The developed UV source has been used for bacterial deactivation studies using an experimental setup that is an equivalent of the conventional house-hold water purifier system. Deactivation studies for five types of bacteria, i.e., E. coli, Shigella boydii, Vibrio, Coliforms and Fecal coliform have been demonstrated with 4 log reductions in less than ten seconds.

  17. Removal of atrazine in water by combination of activated carbon and dielectric barrier discharge

    Energy Technology Data Exchange (ETDEWEB)

    Vanraes, Patrick, E-mail: patrick.vanraes@ugent.be [Department of Applied Physics, Ghent University, Sint-Pietersnieuwstraat 41 B4, 9000 Gent (Belgium); Willems, Gert; Nikiforov, Anton [Department of Applied Physics, Ghent University, Sint-Pietersnieuwstraat 41 B4, 9000 Gent (Belgium); Surmont, Pieter; Lynen, Frederic [Separation Science Group, Department of Organic Chemistry, Ghent University, Krijgslaan 281 S4-bis, 9000 Gent (Belgium); Vandamme, Jeroen; Van Durme, Jim [Research Group Molecular Odor Chemistry, Department of Microbial and Molecular Systems (M2S), KU Leuven, Technology Campus, Gebroeders De Smetstraat 1, 9000 Gent (Belgium); Verheust, Yannick P.; Van Hulle, Stijn W.H.; Dumoulin, Ann [Department of Industrial Biological Sciences, Ghent University, Graaf Karel de Goedelaan 5, 8500 Kortrijk (Belgium); Leys, Christophe [Department of Applied Physics, Ghent University, Sint-Pietersnieuwstraat 41 B4, 9000 Gent (Belgium)

    2015-12-15

    Highlights: • Increasing input power with a factor 3.5 leads to deeper atrazine oxidation without significantly changing energy yield of atrazine removal. • Chlorine containing oxidation by-products of first and later generations are detected with HPLC–MS analysis, in agreement with literature. • Desorption analysis shows lower atrazine concentration and higher by-product concentration on activated carbon textile after plasma treatment. • Comparison with plasma reactors described in literature for atrazine decomposition confirms relatively high energy efficiency of our reactor. - Abstract: Efficiency of modern wastewater treatment plants to remove or decompose persistent contaminants in low concentration is often insufficient to meet the demands imposed by governmental laws. Novel, efficient and cheap methods are required to address this global issue. We developed a new type of plasma reactor, in which atrazine decomposition by atmospheric dielectric barrier discharge (DBD) in dry air is combined with micropollutant adsorption on activated carbon textile and with extra bubbling of generated ozone. Investigation of reaction kinetics and by-product analysis shows that increasing input power with a factor 3.5 leads to deeper atrazine oxidation without significantly changing energy yield of atrazine removal. By-products of first and later generations are detected with HPLC–MS analysis in water and adsorbed on the activated carbon textile. Our reactor is compared in energy efficiency with reactors described in literature, showing that combination of plasma discharge with pollutant adsorption and ozone recycling is attractive for future applications of water treatment.

  18. Removal of atrazine in water by combination of activated carbon and dielectric barrier discharge

    International Nuclear Information System (INIS)

    Vanraes, Patrick; Willems, Gert; Nikiforov, Anton; Surmont, Pieter; Lynen, Frederic; Vandamme, Jeroen; Van Durme, Jim; Verheust, Yannick P.; Van Hulle, Stijn W.H.; Dumoulin, Ann; Leys, Christophe

    2015-01-01

    Highlights: • Increasing input power with a factor 3.5 leads to deeper atrazine oxidation without significantly changing energy yield of atrazine removal. • Chlorine containing oxidation by-products of first and later generations are detected with HPLC–MS analysis, in agreement with literature. • Desorption analysis shows lower atrazine concentration and higher by-product concentration on activated carbon textile after plasma treatment. • Comparison with plasma reactors described in literature for atrazine decomposition confirms relatively high energy efficiency of our reactor. - Abstract: Efficiency of modern wastewater treatment plants to remove or decompose persistent contaminants in low concentration is often insufficient to meet the demands imposed by governmental laws. Novel, efficient and cheap methods are required to address this global issue. We developed a new type of plasma reactor, in which atrazine decomposition by atmospheric dielectric barrier discharge (DBD) in dry air is combined with micropollutant adsorption on activated carbon textile and with extra bubbling of generated ozone. Investigation of reaction kinetics and by-product analysis shows that increasing input power with a factor 3.5 leads to deeper atrazine oxidation without significantly changing energy yield of atrazine removal. By-products of first and later generations are detected with HPLC–MS analysis in water and adsorbed on the activated carbon textile. Our reactor is compared in energy efficiency with reactors described in literature, showing that combination of plasma discharge with pollutant adsorption and ozone recycling is attractive for future applications of water treatment.

  19. Contribution of supra-permafrost discharge to thermokarst lake water balances on the northeastern Qinghai-Tibet Plateau

    Science.gov (United States)

    Pan, Xicai; Yu, Qihao; You, Yanhui; Chun, Kwok Pan; Shi, Xiaogang; Li, Yanping

    2017-12-01

    The seasonal hydrological mechanisms of two thermokarst lakes on the northeastern Qinghai-Tibet Plateau (QTP) were characterized by three-year intensive field observations and a water balance model. In three ice-free seasons, the supra-permafrost discharge contributed a mean ratio of over 170% of the precipitation. In the ice-cover seasons, the supra-permafrost discharge contribution varied between -20% and 22% of the water storage change. Results show that a large portion of the lake water storage change is because of the supra-permafrost discharge resulting from precipitation. Furthermore, a precipitation-subsurface runoff function is preliminarily identified in which the supra-permafrost discharge nonlinearly increased with more precipitation. Our results show that the recent lake expansion is linked with increasing supra-permafrost discharge dominated by precipitation. This study also suggests that we need to pay attention to the nonlinear increase of precipitation-controlled supra-permafrost discharge on the large lake expansion at the catchment scale in the QTP region, instead of only looking at the inputs (e.g., precipitation and river discharge) as shown in the previous studies.

  20. Note: Influence of rinsing and drying routines on growth of multilayer thin films using automated deposition system.

    Science.gov (United States)

    Gamboa, Daniel; Priolo, Morgan A; Ham, Aaron; Grunlan, Jaime C

    2010-03-01

    A versatile, high speed robot for layer-by-layer deposition of multifunctional thin films, which integrates concepts from previous dipping systems, has been designed with dramatic improvements in software, positioning, rinsing, drying, and waste removal. This system exploits the electrostatic interaction of oppositely charged species to deposit nanolayers (1-10 nm thick) from water onto the surface of a substrate. Dip times and number of deposited layers are adjustable through a graphical user interface. In between dips the system spray rinses and dries the substrate by positioning it in the two-tiered rinse-dry station. This feature significantly reduces processing time and provides the flexibility to choose from four different procedures for rinsing and drying. Assemblies of natural montmorillonite clay and polyethylenimine are deposited onto 175 microm poly(ethylene terephthalate) film to demonstrate the utility of this automated deposition system. By altering the type of rinse-dry procedure, these clay-based assemblies are shown to exhibit variations in film thickness and oxygen transmission rate. This type of system reproducibly deposits films containing 20 or more layers and may also be useful for other types of coatings that make use of dipping.

  1. Guidance for a harmonized emission scenario document (ESD) on ballast water discharge

    Energy Technology Data Exchange (ETDEWEB)

    Zipperle, Andreas [BIS - Beratungszentrum fuer integriertes Sedimentmanagement, Hamburg (Germany); Gils, Jos van [DELTARES, Delft (Netherlands); Hattum, Bert van [Amsterdam Univ. (Netherlands). IVM - Institute for Environmental Studies; Heise, Susanne [BIS - Beratungszentrum fuer integriertes Sedimentmanagement, Hamburg (Germany); Hamburg Univ. of Applied Sciences (Germany)

    2011-05-15

    The present report provides guidance for a harmonized Emission Scenario Document (ESD) for the exposure assessment as part of the environmental risk assessment process which applicants seeking approval of a ballast water management system (BWMS) need to perform prior to notification and authorisation procedures. Despite the global variability of the marine environment, ballast water discharges and treatment methods, exposure assessments need to be comparable between different applications. In order to achieve this, this ESD points out the following aspects: - Applicants should use standardized scenarios in order to predict mean exposure. These should reflect generic situations, independent of region or port so that results are widely applicable. In addition to a harbour scenario, a standardized shipping lane scenario should be considered, - During or right after ballast water discharge, high concentrations may persist in a water body for a certain length of time until extensive mixing results in mean concentrations. Not taking exposure to peak concentrations within gradients into account could lead to an underestimation of risk, especially for rapidly degrading substances. Efforts have been made to approximate maximum exposure concentration with simple dilution factors. Their applicability was checked by near-field-evaluations. - Chemical properties determine the environmental fate of substances. If they are ambiguous, selection of a specific set of data strongly influences the result of an exposure assessment. Guidance is given on what to do about lacking data. - In order to harmonize the exposure assessments, reliable chemical model software should be used. A discussion on the requirements of suitable software and an evaluation of MAMPEC is given in this report. (orig.)

  2. Impacts of Columbia River discharge on salmonid habitat: 2. Changes in shallow-water habitat

    Science.gov (United States)

    Kukulka, Tobias; Jay, David A.

    2003-09-01

    This is the second part of an investigation that analyzes human alteration of shallow-water habitat (SWH) available to juvenile salmonids in the tidal Lower Columbia River. Part 2 develops a one-dimensional, subtidal river stage model that explains ˜90% of the stage variance in the tidal river. This model and the tidal model developed in part 1 [, 2003] uncouple the nonlinear interaction of river tides and river stage by referring both to external forcing by river discharge, ocean tides, and atmospheric pressure. Applying the two models, daily high-water levels were predicted for a reach from rkm-50 to rkm-90 during 1974 to 1998, the period of contemporary management. Predicted water levels were related to the bathymetry and topography to determine the changes in shallow-water habitat area (SWHA) caused by flood control dikes and altered flow management. Model results suggest that diking and a >40% reduction of peak flows have reduced SWHA by ˜62% during the crucial spring freshet period during which juvenile salmon use of SWHA is maximal. Taken individually, diking and flow cycle alteration reduced spring freshet SWHA by 52% and 29%, respectively. SWHA has been both displaced to lower elevations and modified in its character because tidal range has increased. Our models of these processes are economical for the very long simulations (seasons to centuries) needed to understand historic changes and climate impacts on SWH. Through analysis of the nonlinear processes controlling surface elevation in a tidal river, we have identified some of the mechanisms that link freshwater discharge to SWH and salmonid survival.

  3. Surface modification of polyimide (PI) film using water cathode atmospheric pressure glow discharge plasma

    International Nuclear Information System (INIS)

    Zheng Peichao; Liu Keming; Wang Jinmei; Dai Yu; Yu Bin; Zhou Xianju; Hao Honggang; Luo Yuan

    2012-01-01

    Highlights: ► Equipment called water cathode atmospheric pressure glow discharge was used to improve the hydrophilicity of polyimide films. ► The data shows good homogeneity and the variation trends of contact angles are different for polar and non-polar testing liquids. ► The thickness of liquid layer plays an important role in plasma processing and directly affects the treatment effect. ► Surface hydrophilicity after plasma treatment is improved partly due to the increase in the roughness. ► The hydrophilicity of polyimide films is still better than untreated ones after long-term storage. - Abstract: The industrial use of polyimide film is limited because of undesirable properties such as poor wettability. In the present paper, a new kind of equipment called water cathode atmospheric pressure glow discharge was used to improve the surface properties of polyimide films and made them useful to technical applications. The changes in hydrophilicity of modified polyimide film surfaces were investigated by contact angle, surface energy and water content measurements as a function of treatment time. The results obtained show good treatment homogeneity and that the variation trends of contact angles are different for polar and non-polar testing liquids, while surface energy and water content are significantly enhanced with the increase of treatment time until they achieve saturated values after 60 s plasma treatment. Also, the thickness of liquid layer plays an important role in plasma processing and directly affects the treatment effect. Changes in morphology of polyimide films were analyzed by atomic force microscope and the results indicate that surface hydrophilicity after plasma treatment are improved partly due to the increase in the roughness. In addition, polyimide films treated by plasma are subjected to an ageing process to determine the durability of plasma treatment. It is found that the hydrophilicity is still better than untreated ones though the

  4. Late quaternary history and uranium isotopic compositions of ground water discharge deposits, Crater Flat, Nevada

    International Nuclear Information System (INIS)

    Paces, J.B.; Taylor, E.M.; Bush, C.

    1993-01-01

    Three carbonate-rich spring deposits are present near the southern end of Crater Flat, NV, approximately 18 km southwest of the potential high-level waste repository at Yucca Mountain. We have analyzed five samples of carbonate-rich material from two of the deposits for U and Th isotopic compositions. Resulting U-series disequilibrium ages indicate that springs were active at 18 ± 1, 30 ± 3, 45 ± 4 and >70 ka. These ages are consistent with a crude internal stratigraphy at one site. Identical ages for two samples at two separate sites suggest that springs were contemporaneous, at least in part, and were most likely part of the same hydrodynamic system. In addition, initial U isotopic compositions range from 2.8 to 3.8 and strongly suggest that ground water from the regional Tertiary-volcanic aquifer provided the source for these hydrogenic deposits. This interpretation, along with water level data from near-by wells suggest that the water table rose approximately 80 to 115 m above present levels during the late Quaternary and may have fluctuated repeatedly. Current data are insufficient to allow reconstruction of a detailed depositional history, however geochronological data are in a good agreement with other paleoclimatic proxy records preserved throughout the region. Since these deposits are down gradient from the potential repository site, the possibility of higher ground water levels in the future dramatically shortens both vertical and lateral ground water pathways and reduces travel times of transported radionuclides to potential discharge sites

  5. Late quaternary history and uranium isotopic compositions of ground water discharge deposits, Crater Flat, Nevada

    Science.gov (United States)

    Paces, James B.; Taylor, Emily M.; Bush, Charles

    1993-01-01

    Three carbonate-rich spring deposits are present near the southern end of Crater Flat, NV, approximately 18 km southwest of the potential high-level waste repository at Yucca Mountain. We have analyzed five samples of carbonate-rich material from two of the deposits for U and Th isotopic compositions. Resulting U-series disequilibrium ages indicate that springs were active at 18 ?? 1, 30 ?? 3, 45 ?? 4 and >70 ka. These ages are consistent with a crude internal stratigraphy at one site. Identical ages for two samples at two separate sites suggest that springs were contemporaneous, at least in part, and were most likely part of the same hydrodynamic system. In addition, initial U isotopic compositions range from 2.8 to 3.8 and strongly suggest that ground water from the regional Tertiary-volcanic aquifer provided the source for these hydrogenic deposits. This interpretation, along with water level data from near-by wells suggest that the water table rose approximately 80 to 115 m above present levels during the late Quaternary and may have fluctuated repeatedly. Current data are insufficient to allow reconstruction of a detailed depositional history, however geochronological data are in good agreement with other paleoclimatic proxy records preserved throughout the region. Since these deposits are down gradient from the potential repository site, the possibility of higher ground water levels in the future dramatically shortens both vertical and lateral ground water pathways and reduces travel times of transported radionuclides to potential discharge sites.

  6. Treatment of EDTA contained reactor coolant using water dielectric barrier discharge plasma

    International Nuclear Information System (INIS)

    Song, Sang Heon; Kwon, Daniel; Kim, Gon Ho

    2005-01-01

    EDTA (Ethylene Diamine Tetraacetic Acid) is used as a main absorbent for the metal ion in the secondary loop of the nuclear reactor. Dissolving the wasted EDTA with low cost, therefore, is important issue for the maintenance of the nuclear power reactor and the protection of environment. EDTA is not easily biodegradable, furthermore these methods could make remained another pollutant as complex chemical compounds. Compared to chemical method, the physical methods, using the energetic particles and UVs, are more favorable because they dissociate the bonds of organic compounds directly without the secondary chemical reactions during the treatment. Recently, high energy electron beam, the plasma torch, and the water breakdown by high voltage pulse are applied to treatment of the waste water contained chemicals. Here consideration is narrow down to improve the interaction between the plasma and the chemical bonds of EDTA because the energetic particles; activated radicals, and UVs, are abundant in plasmas. The new method adapted of the water DBD (dielectric barrier discharge) which plasma generates directly on the top of the water contained EDTA is proposed. The application of DBD plasmas has been extended for cleaning the organic compounds from the contaminated surface and also for removing volatile organic chemicals (VOC) such as NO x and SO x from the exhausted gases. Here, the water DBD reactor (SEMTECH, SD-DWG-04-1) is consisted that the one electrode is a ceramic insulator and another one is the water itself. Interestingly, the one electrode, the water, is not the solid dielectric electrode. In this study, therefore, the characteristics with driving frequency are considered and the feasibility of this new method for the DBD treatment of EDTA contained water is demonstrated

  7. Transport and transformation of pharmaceuticals and other contaminants of emerging concern from wastewater discharge through surface water to drinking water intake and treatment

    Science.gov (United States)

    The ubiquitous presence of pharmaceuticals, hormones, and other contaminants of emerging concern (CECs) in surface-water resources have necessitated research that better elucidates pathways of transport and transformation for these compounds from their discharged wastewater, thro...

  8. Microelement Exploration Water Flow of Rimnik River

    OpenAIRE

    , N. Bajraktari; , B. Baraj; , T. Arbneshi; , S. Jusufi

    2016-01-01

    Compared to the increasing need on qualitative water use, many water şows are subject to a rising pollution by urban and industrial untreated water discharge, and in some cases by incidental run-offs. Besides them, there is also a great impact made by disseminated agricultural pollution and air and soil rinsing after atmospheric rainfalls. The main purpose of this paper is the micro-element exploration in water and sediments, along the water şow of Rimnik River. Some of the heavy metals: Pb, ...

  9. Experimental investigation on the relationship between sluice caisson shape of tidal power plant and the water discharge capability

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Dal Soo; Oh, Sang-Ho; Yi, Jin-Hak; Park, Woo-Sun [Coastal Engineering and Ocean Energy Research Department, Korea Ocean Research and Development Institute, Ansan 426-744 (Korea); Cho, Hyu-Sang; Kim, Duk-Gu; Ahn, Suk-Jin [Technology Research and Development Institute, Hyein E and C Co. Ltd., Seoul 157-861 (Korea); Eom, Hyun-Min [Global Environment System Research Laboratory, National Institute of Meteorological Research/KMA, Seoul 156-720 (Korea)

    2010-10-15

    The change of water discharge capability of the sluice caisson of tidal power plant according to the change of geometrical shape of the sluice caisson was investigated by performing laboratory experiments. The major design parameters that constitute general shape of the sluice caisson were deduced and a total of 32 different shapes of sluice caisson models were subjected to the hydraulic experiments. For every sluice caisson model, the water discharge capability was estimated with five different flow rates and three different water level conditions. The experiments were carried out in an open channel flume with a great care to measure flow rate and water level accurately, which are key physical quantities in estimating the water discharge capability of the sluice caisson models. By analyzing the experimental results, influence of the respective design parameters on the performance of the sluice caisson was examined and the general guidelines to enhance the water discharge capability were suggested. The discharge coefficient of the best sluice caisson model ranged from 2.3 to 3.1 depending on the experimental conditions, which is far higher than the values that were adopted in the past feasibility studies in Korea. (author)

  10. Effects of a non-rinse conditioner on the enamel of primary teeth

    Directory of Open Access Journals (Sweden)

    Fava Marcelo

    2003-01-01

    Full Text Available The aim of this in vitro study was to evaluate by scanning electron microscopy the morphological aspects of the enamel of primary teeth after etching with 36% phosphoric acid or a non-rinse conditioner. Ten naturally exfoliated anterior primary teeth were selected. The samples were subjected to prophylaxis with pumice paste and water using a low-speed hand piece. Etching was done on the buccal surface. Specimens were divided into 2 groups: G1 (n=10: etching with 36% phosphoric acid gel - Conditioner 36 (Dentsply for 20 s, followed by water rinse for 15 s; G2 (n=10: etching with NRC - Non Rinse Conditioner (Dentsply for 20 s, followed by air drying for 15 s. The samples were dehydrated, mounted on metal stubs, coated with gold and observed with Jeol JSM-6100 scanning electron microscope. Electron-micrographic analysis showed that both etching agents were effective for etching the enamel of primary teeth causing the formation of microporosities on the enamel surface, although the etching pattern was more effective with the use of 36% phosphoric acid gel.

  11. Metal speciation and potential bioavailability changes during discharge and neutralisation of acidic drainage water.

    Science.gov (United States)

    Simpson, Stuart L; Vardanega, Christopher R; Jarolimek, Chad; Jolley, Dianne F; Angel, Brad M; Mosley, Luke M

    2014-05-01

    The discharge of acid drainage from the farm irrigation areas to the Murray River in South Australia represents a potential risk to water quality. The drainage waters have low pH (2.9-5.7), high acidity (up to 1190 mg L(-1) CaCO3), high dissolved organic carbon (10-40 mg L(-1)), and high dissolved Al, Co, Ni and Zn (up to 55, 1.25, 1.30 and 1.10 mg L(-1), respectively) that represent the greatest concern relative to water quality guidelines (WQGs). To provide information on bioavailability, changes in metal speciation were assessed during mixing experiments using filtration (colloidal metals) and Chelex-lability (free metal ions and weak inorganic metal complexes) methods. Following mixing of drainage and river water, much of the dissolved aluminium and iron precipitated. The concentrations of other metals generally decreased conservatively in proportion to the dilution initially, but longer mixing periods caused increased precipitation or adsorption to particulate phases. Dissolved Co, Mn and Zn were typically 95-100% present in Chelex-labile forms, whereas 40-70% of the dissolved nickel was Chelex-labile and the remaining non-labile fraction of dissolved nickel was associated with fine colloids or complexed by organic ligands that increased with time. Despite the different kinetics of precipitation, adsorption and complexation reactions, the dissolved metal concentrations were generally highly correlated for the pooled data sets, indicating that the major factors controlling the concentrations were similar for each metal (pH, dilution, and time following mixing). For dilutions of the drainage waters of less than 1% with Murray River water, none of the metals should exceed the WQGs. However, the high concentrations of metals associated with fine precipitates within the receiving waters may represent a risk to some aquatic organisms. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.

  12. Impact assessment wastewater discharge on water quality DTD canal Bečej-Bogojevo

    Directory of Open Access Journals (Sweden)

    Pešić Vesna Ž.

    2015-01-01

    Full Text Available Pressure and impact analysis requires information on the main drivers and changes in conditions. In order to analyze such pressures and impacts, each river basin requires: an analysis of its characteristics, a review of the impact of human activity on the status of the surface water and an economic analysis of water use. Pressure and impact analysis plays a central role in the planning of river basin management. The quality of the stream at any point depends on several major factors: lithology of the basin, weather conditions, climate, and human impacts. Most of the polluters are located in the big cities next to canal DTD Bečej-Bogojevo canal (Odzaci,Vrbas, Srbobran, Becej. Per year, 2900000 m3 of wastewater was discharged into the Bečej-Bogojevo section of the DTD canal: 1,4 tCOD, 0,8 0tBOD, 260 kg of nitrogen, 19 kg of phosphorus and 282 kg of suspended solids. Of the total volume of wastewater, 20% comes from industry and 80% from municipal wastewater. Most of the wastewaters from the studied polluters is discharged untreated or insufficiently treated (only primary treatment. This poor quality wastewater threatens the receipients into which its is discharged. Comparison of the wastewater quality results to the Decree on emission limits and deadlines for their achievement, shows that many polluters exceed the limits for all parameters (COD, BOD, nitrogen, phosphorus, suspended solids. On the basis of the physico-chemical analysis of the water from the DTD Bečej-Bogojevo canal it can be concluded that the water quality is unsatisfactory. According to the national legislation, the water quality exceeds the values for good potential streams for most parameters at all sampling locatio dissolved oxygen, organic matter and nutrients. Thus, we can conclude that the water in the studied section of the DTD Bečej-Bogojevo canal does not meet the criteria for "good ecological potential". The most vulnerable locations are downstream of the Vrbas and

  13. The effect of electrical conductivity on nanosecond discharges in distilled water and in methanol with argon bubbles

    KAUST Repository

    Hamdan, Ahmad

    2017-03-27

    We investigated the effect of a liquid\\'s electrical conductivity (EC) on the physical characteristics of electrical discharges in liquids with gaseous bubbles. Argon gas was supplied into the liquid to form an array of gaseous bubbles in between two electrodes (a pin-to-hollow electrode setup). Methanol and water were considered as base liquids, representing a low and a high dielectric permittivity (ϵ) liquid respectively, while potassium chloride (KCl) was added to control the EC of the liquids. When increasing the EC of the liquids, we found that the discharge probability was reduced by 46% for in-water and 38% for in-methanol discharges. We also found that the injected charge decreased by ∼4 μC as the EC increased. Moreover, as the gap distance increased from 1 to 2.5 mm, the injected charge decreased by 2 μC for in-water discharge and by 4 μC for in-methanol discharge. The plasma emission is another important parameter in characterizing discharges. With increasing the EC, the plasma emission volume decreased linearly by a factor of ∼5. The plasma lifetime was shortened by around 33% for in-water and 20% for in-methanol discharges in the case of d = 1 mm, while the decrease was 40% for in-water and 30% for in-methanol discharges in the case of d = 2.5 mm. Using the broadening characteristics of the Hα line, the electron density was estimated during the first 100 ns by ∼3 × 10 cm for in-water discharges and by ∼2 × 10 cm for in-methanol discharges, and it decreased by about one order of magnitude after 800 ns; note that n dependence on the EC was not significant. The reported findings provide further understanding of electrical discharges in bubbled liquids and highlight the influence of a liquid\\'s EC, which are useful in the development and optimization of the applications based on such process.

  14. Thermal pollution of rivers and reservoirs by discharges of heated water from thermal and nuclear power plants

    International Nuclear Information System (INIS)

    Makarov, I.

    1974-12-01

    The problems are discussed of the thermal pollution of rivers and water reservoirs by discharges of heated water from thermal and nuclear power plants. The problems concerned are quantitative and qualitative changes in biocenoses, the disturbance or extinction of flora and fauna, physiological changes in organisms and changes in the hydrochemical regime. (Z.M.)

  15. Letter from A & R Transport about Section 308 of the Clean Water Act Discharge of Perfluorinated Compounds

    Science.gov (United States)

    January 16, 2009 letter from Kenneth E. Pate, VP of Safety and Risk Management of A & R Transport, Inc. to EPA Clean Water Enforcement Branch, about an Information Request about the Section 308 of the Clean Water Act, discharge of pefluorinated compounds.

  16. CFD modelling of axial mixing in the intermediate and final rinses of cleaning-in-place procedures of straight pipes

    DEFF Research Database (Denmark)

    Yang, Jifeng; Jensen, Bo Boye Busk; Nordkvist, Mikkel

    2018-01-01

    The intermediate and final rinses of straight pipes, in which water replaces a cleaning agent of similar density and viscosity, are modelled using Computational Fluid Dynamic (CFD) methods. It is anticipated that the displacement process is achieved by convective and diffusive transport. The simu...

  17. A model to calculate exposure from radioactive discharges into the coastal waters of Northern Europe

    International Nuclear Information System (INIS)

    Clark, M.J.; Grimwood, P.D.; Camplin, W.C.

    1980-11-01

    A regional marine model is described which can be used to estimate the exposure of populations as a result of the discharge of radioactive effluents into the coastal waters of Northern Europe. The model simulates the dispersion of radionuclides in marine waters, Their interaction with marine sediments and the concentration mechanisms occurring in seafoods. There is a local/regional interface defined in the modelling approach whereby releases are assumed to first enter a local marine compartment prior to widespread dispersion in coastal waters. Depletion mechanisms operate within both the local and regional environments influencing the fraction of radionuclide release which contributes to collective exposure. General results of the regional marine model are presented in a form which can be combined with independent local marine models; collective intakes per unit release of various radionuclides into coastal waters are given for a series of integration times. For caesium-137 and plutonium-239 collective effective dose equivalent commitments have been calculated using a defined local marine model. Some general conclusions have been drawn from the results and there is some discussion of the various features of the modelling approach. (author)

  18. Forested wetland mitigation resulting from discharges of cooling water into streams

    International Nuclear Information System (INIS)

    Nelson, E.A.

    1993-01-01

    The Savannah River Swamp is a 3020-ha forested wetland on the floodplain of the Savannah River and is located on the US Department of Energy's Savannah River Site (SRS) near Aiken, South Carolina. Historically, the swamp consisted of ∼50% bald cypress-water tupelo stands, 40% mixed bottomland hardwood stands, and 10% shrub, marsh, and open water. The hydrology was controlled by flooding the Savannah River and by flow from four creeks that drain into the swamp prior to flow into the Savannah River. Upstream dams have caused some alteration of the water levels and timing of flooding within the floodplain. Major impacts to the swamp hydrology occurred with the completion of the production reactors and one coal-fired powerhouse at the SRS in the early 1950s. Water, often in excess of 40 to 50 degrees C was discharged into one of the small streams from 1954 to 1988, at various levels, ranging from 20 to 40 times the prior flow rate of the stream. This had a major impact on the adjacent swamp land, with erosion, silting, and vegetation destruction. The Final Environmental Impact Statement, Continued Operation of K, L, and P Reactors, Savannah River Site, Aiken, South Carolina, and the subsequent record of decision directed that these areas be restored to functional forested wetland status to the extent possible. This paper describes work begun to reach that objective

  19. Effect of the Discharge Water which Mixed Sewage Disposal Water with Seawater Desalting Treated Sewage for Bottom Sediment and Hypoxic Water Mass

    Science.gov (United States)

    Watanabe, Ryoichi; Yamasaki, Koreyoshi; Minagawa, Tomoko; Iyooka, Hiroki; Kitano, Yoshinori

    For every time in summer season, hypoxic water mass has formed at the inner part of Hakata Bay. Field observation study has carried out at the inner part of Hakata Bay since 2004 with the particular aim of tracking the movement of hypoxic water mass. Hypoxic water masses form the end of June to September on this area because the consumption of oxygen in bottom water layers exceeds the re-supply of oxygen from the atmosphere. Under such hypoxic conditions, the seawater desalination plant has begun to use in 2005. After seawater desalination plant operation starting, hypoxic water mass tends to improve. In this research, the authors show the following result. After seawater desalination plant has begun to operate, the hypoxia around the mixed discharge water outlet tends to be improved.

  20. Study of thermal and hydraulic phenomena going along with the discharge of hot waters from a power generation plant

    International Nuclear Information System (INIS)

    Syrmalenios, Panayotis

    1973-01-01

    This short research thesis aims at taking stock of problems raised by the discharge of high temperature water from a power plant into rivers, lakes and seas from a thermal and hydraulic point of view. The author proposes an overview of ecological, legal, and recirculation problems. He describes the various phenomena going along these discharges at the vicinity of the discharge and far from it. He also proposes an overview of methods used to study these thermal and hydraulic effects: 'in-situ' studies, experimental methods, theoretical methods. Appendices address floating jets and layered flows [fr

  1. The catalytic role of tungsten electrode material in the plasmachemical activity of a pulsed corona discharge in water

    Czech Academy of Sciences Publication Activity Database

    Lukeš, Petr; Člupek, Martin; Babický, Václav; Sisrová, I.; Janda, V.

    2011-01-01

    Roč. 20, č. 3 (2011), 034011-034011 ISSN 0963-0252 R&D Projects: GA AV ČR IAAX00430802; GA ČR(CZ) GD104/09/H080 Institutional research plan: CEZ:AV0Z20430508 Keywords : corona discharge * water * erosion * tungsten * hydrogen peroxide * dimethylsulfoxide Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 2.521, year: 2011 http://www.ipp.cas.cz/Ips/public/lukes_2011a.pdf

  2. The concentration-discharge slope as a tool for water quality management.

    Science.gov (United States)

    Bieroza, M Z; Heathwaite, A L; Bechmann, M; Kyllmar, K; Jordan, P

    2018-07-15

    Recent technological breakthroughs of optical sensors and analysers have enabled matching the water quality measurement interval to the time scales of stream flow changes and led to an improved understanding of spatially and temporally heterogeneous sources and delivery pathways for many solutes and particulates. This new ability to match the chemograph with the hydrograph has promoted renewed interest in the concentration-discharge (c-q) relationship and its value in characterizing catchment storage, time lags and legacy effects for both weathering products and anthropogenic pollutants. In this paper we evaluated the stream c-q relationships for a number of water quality determinands (phosphorus, suspended sediments, nitrogen) in intensively managed agricultural catchments based on both high-frequency (sub-hourly) and long-term low-frequency (fortnightly-monthly) routine monitoring data. We used resampled high-frequency data to test the uncertainty in water quality parameters (e.g. mean, 95th percentile and load) derived from low-frequency sub-datasets. We showed that the uncertainty in water quality parameters increases with reduced sampling frequency as a function of the c-q slope. We also showed that different sources and delivery pathways control c-q relationship for different solutes and particulates. Secondly, we evaluated the variation in c-q slopes derived from the long-term low-frequency data for different determinands and catchments and showed strong chemostatic behaviour for phosphorus and nitrogen due to saturation and agricultural legacy effects. The c-q slope analysis can provide an effective tool to evaluate the current monitoring networks and the effectiveness of water management interventions. This research highlights how improved understanding of solute and particulate dynamics obtained with optical sensors and analysers can be used to understand patterns in long-term water quality time series, reduce the uncertainty in the monitoring data and to

  3. Delineation of thermal effluents discharged into tropical waters around Puerto Rico by aerial infrared scanning

    International Nuclear Information System (INIS)

    Wood, E.D.

    1975-01-01

    Aerial infrared scanning offers a versatile tool with which to monitor thermal discharges and a rapid method of detecting extraneous discharges, whose temperatures differ from the ambient waters. Knowledge of the extent and distribution of thermal effluents is necessary to assist in determining the effects of the added heat upon biota of the region. An AGA Model 680 Thermovision infrared scanner with a 45 0 lens was mounted in a Cessna 182, and flown at altitudes of 600 to 2000 m during night and twilight hours. The detector was InSb, cooled with liquid nitrogen and sensitive to the range 2 to 5.6 μm. The picture was originally displayed on a color monitor which assigned ten arbitrary colors to shades of gray on the control unit. Isotherms have been assigned using coincidental surface measurements made with a thermometer, read to the nearest 0.1 0 C. The data were then recorded on film. Ranges were set at 2 0 C and 5 0 C, common sensitivities were 0.2 0 C and 0.5 0 C, respectively. More recently, the data have been recorded on magnetic tapes with a Sabre III instrumentation tape recorder. Observed data have been compared to predictions made using the Pritchard Plume Model. Anomalies can be explained by boundary, wind, and tidal effects. (U.S.)

  4. Power supply improvements for ballasts-low pressure mercury/argon discharge lamp for water purification

    Science.gov (United States)

    Bokhtache, A. Aissa; Zegaoui, A.; Djahbar, A.; Allouache, H.; Hemici, K.; Kessaissia, F. Z.; Bouchrit, M. S.; Aillerie, M.

    2017-02-01

    The low-pressure electrical discharges established in the mercury rare gas mixtures are the basis of many applications both in the field of lighting and for industrial applications. In order to select an efficient high frequency power supply (ECG -based PWM inverter), we present and discuss results obtained in the simulation of three kinds of power supplies delivering a 0.65 A - 50KHz sinusoidal current dedicated to power low pressure UV Mercury - Argon lamp used for effect germicide on water treatment thus allowing maximum UVC radiation at 253.7 nm. Three ballasts half-bridge configurations were compared with criteria based on resulting germicide efficiency, electrical yield and reliability, for example the quality of the sinusoidal current with reduced THD, and finally, we also considered in this analysis the final economic aspect.

  5. Estimating the monthly discharge of a photovoltaic water pumping system: Model verification

    International Nuclear Information System (INIS)

    Amer, E.H.; Younes, M.A.

    2006-01-01

    A simple algorithm has been adopted for estimating the long term performance of a photovoltaic water pumping system without battery storage. The method uses the standard solar utilizability correlation equation to calculate the flow rate of the system, knowing an insolation threshold value. The method uses the monthly average solar radiation as the only input. The nonlinear relation between flow rate and solar insolation has been obtained experimentally in a first step and then used for performance prediction. The meteorological data collected instantaneously at the site of the pumping system has been used to obtain the monthly average values for solar radiation that are needed by the method. The method has been validated by predicting the performance of two PV pumping systems. The average output of the systems predicted by the method has been compared with experimental measurements. The estimated discharge differs by about 5% from the experimental measurements

  6. Economic, Energetic, and Environmental Impact Evaluation of the Water Discharge Networks from Mining Works

    Directory of Open Access Journals (Sweden)

    Andrei Cristian Rada

    2018-01-01

    Full Text Available Sustainable development represents an optimistic scenario for the evolution of contemporary civilization. The object of this paper is to define certain evaluation criteria regarding the performances of water discharge networks from mining works, and propose a method for aggregating the specific indicators for monetary costs, energetic costs, and environmental impact-related costs. The global pollution index (GPI represents a method for assessing environment health status or pollution levels. The GPI quantitatively expresses this status based on its index, which results from a ratio between the ideal value and the given value of certain quality indices that are considered specific for the analyzed environmental factors at certain moments. The proposed method in this paper tries to perform a synergistic aggregation of the balance sheet of harmfulness and classic balance sheets for matter and energy for an industrial process.

  7. Synthesis of SiOC:H nanoparticles by electrical discharge in hexamethyldisilazane and water

    KAUST Repository

    Hamdan, Ahmad

    2017-07-25

    Nanoparticles have unique properties and are useful in many applications. Efficient synthesis of high yields of nanoparticles remains a challenge. Here, we synthesized SiOC:H, a low-dielectric-constant material, by electrical discharge at the interface of hexamethyldisilazane and water. The nanoparticle production rate of our technique was ∼17 mg per minute. We used Fourier transform infrared spectroscopy, scanning and transmission electron microscopy, and X-ray photoemission spectroscopy to characterize the synthesized material. Heating the nanoparticles to 500 °C for 2 h released hydrogen from CHx groups and evaporated volatile compounds. Our method to produce high yields of low-dielectric-constant nanoparticles for microelectronic applications is promising.

  8. Synthesis of SiOC:H nanoparticles by electrical discharge in hexamethyldisilazane and water

    KAUST Repository

    Hamdan, Ahmad; Abdul Halim, Rasha; Anjum, Dalaver H.; Cha, Min

    2017-01-01

    Nanoparticles have unique properties and are useful in many applications. Efficient synthesis of high yields of nanoparticles remains a challenge. Here, we synthesized SiOC:H, a low-dielectric-constant material, by electrical discharge at the interface of hexamethyldisilazane and water. The nanoparticle production rate of our technique was ∼17 mg per minute. We used Fourier transform infrared spectroscopy, scanning and transmission electron microscopy, and X-ray photoemission spectroscopy to characterize the synthesized material. Heating the nanoparticles to 500 °C for 2 h released hydrogen from CHx groups and evaporated volatile compounds. Our method to produce high yields of low-dielectric-constant nanoparticles for microelectronic applications is promising.

  9. Pulsed-plasma gas-discharge inactivation of microbial pathogens in chilled poultry wash water.

    Science.gov (United States)

    Rowan, N J; Espie, S; Harrower, J; Anderson, J G; Marsili, L; MacGregor, S J

    2007-12-01

    A pulsed-plasma gas-discharge (PPGD) system was developed for the novel decontamination of chilled poultry wash water. Treatment of poultry wash water in the plasma generation chamber for up to 24 s at 4 degrees C reduced Escherichia coli NCTC 9001, Campylobacter jejuni ATCC 33560, Campylobacter coli ATCC 33559, Listeria monocytogenes NCTC 9863, Salmonella enterica serovar Enteritidis ATCC 4931, and S. enterica serovar Typhimurium ATCC 14028 populations to non-detectable levels ( or = 3 log CFU/ml) in recalcitrant B. cereus NCTC 11145 endospore numbers within 30 s, the level of endospore reduction was dependent on the nature of the sparged gas used in the plasma treatments. Scanning electron microscopy revealed that significant damage occurred at the cellular level in PPGD-treated test organisms. This electrotechnology delivers energy in intense ultrashort bursts, generating products such as ozone, UV light, acoustic and shock waves, and pulsed electric fields that have multiple bactericidal properties. This technology offers an exciting complementary or alternative approach for treating raw poultry wash water and for preventing cross-contamination in processing environments.

  10. A zero discharge green roof system and species selection to optimize evapotranspiration and water retention

    Energy Technology Data Exchange (ETDEWEB)

    Compton, J.S.; Whitlow, T.H. [Cornell, Univ., Urban Horticulture Inst., Ithaca, NY (United States). Dept. of Horticulture

    2006-07-01

    Economic benefits must outweigh costs, with or without governmental subsidies or enforcement in order for green roofs to become commonplace in American cities. Municipal advantages to green roofs include stormwater management, environmental quality and an expansion of the native plant palette. These benefits are difficult to quantify monetarily for the owner of the roof, yet greater water evaporation from storm water attenuation has the ability to increase cooling of the building, an economic benefit to the owner. Current green roof design and testing methods fail to explore systems that maximize stormwater retention and evaporative cooling benefits that are often associated with green roofs. This paper presented the results of a study that investigated an alternate approach that optimizes water loss through evapotranspiration using a zero discharge target and plants that tolerate both medium drought and saturation. Species selection emphasizes native species and salt tolerance, which allows the possibility of grey water irrigation. Species studied include spartina alternafiora and solidago canadensis. Plants were studied over a growing season to examine the rates of ET as they relate to weather conditions, growing media composition and saturation levels, and plant species. The study was conducted on top of a four storey school building located in the South Bronx, New York City. In June 2005, a 3,500 square foot extensive green roof was installed. The conference described the site and study in detail followed by a discussion of the results. This includes a discussion of the planting containers, planting mediums, plant materials, data collection, and irrigation trials. It was concluded that further research is needed to test this concept, and to examine the possibility of supplemental irrigation via off-season rainwater catchment or grey water irrigation. 17 refs., 4 figs.

  11. Effects of produced water discharges on the colonization potential of Macrocystis pyrifera spores

    International Nuclear Information System (INIS)

    Lewis, R.J.; Reed, D.C.

    1993-01-01

    Point sources of pollution (e.g. industrial outfalls) may produce ecological impacts at distant locations if pollutants affect dispersive propagules. The authors used laboratory experiments to determine how exposure to produced water (PW; aqueous fraction of petroleum production that is typically discharged into coastal waters) in the water column influences the colonization potential of giant kelp (Macrocystis pyrifera) spores on the bottom. Spores were maintained in suspension in 18 L containers and exposed to one of five concentrations of PW (0 to 10%) for varying amounts of time. Spore swimming generally decreased with increasing PW concentration and exposure duration, with the specific pattern of decrease differing between experimental trials done at different dates. The effect of exposure duration in the water column on the ability of swimming spores to attach to plastic dishes placed the bottom varied with PW concentration. Spores placed in 1 and 10% PW showed a steady decline in their ability to attach with increased exposure; lower concentrations of PW had no such effects. The proportion of spores that germinated after attachment varied tremendously with exposure duration and date of experimental trial. A low proportion of spores that settled during the first 12 h germinated, indicative of a short period of precompetency. Surprisingly, water column exposure to high concentrations of PW during the first 12 h reduced this precompetent period and greatly improved germination success. The magnitude of this enhancement, however, varied among dates. Delayed expression of PW effects were not observed in developing gametophytes; survival of individuals that successfully germinated and gamete production was not affected by previous exposure to PW as a spore

  12. Effect of inflow discharges on the development of matric suction and volumetric water content for dike during overtopping tests

    Science.gov (United States)

    Hassan, Marwan A.; Ismail, Mohd A. M.

    2017-10-01

    The point of this review is to depict the impact of various inflow discharge rate releases on the instruments of matric suction and volumetric water content during an experimental test of spatial overtopping failure at school of civil engineering in universiti Sains of Malaysia. A dry sand dike was conducted inside small flume channel with twelve sensors of tensiometer and Time-Domain Reflectometer (TDR). Instruments are installed in the soil at different locations in downstream and upstream slopes of the dike for measuring the response of matric suction and volumetric water content, respectively. Two values of inflow discharge rates of 30 and 40 L/min are utilized as a part of these experiments to simulate the effectiveness of water reservoirs in erosion mechanism. The outcomes demonstrate that the matric suction and volumetric water content are decreased and increased, respectively for both inflow discharges. The higher inflow discharges accelerate the saturation of dike soil and the erosion process faster than that for the lower inflow discharges.

  13. In vitro study of the effect of an essential oil and a delmopinol mouth rinse on dental plaque bacteria.

    Science.gov (United States)

    LuIs, Henrique Soares; Luis, Luis Soares; Bernardo, Mário

    2016-01-01

    Mouthrinses are used, by many of our patients, as a complement to daily dental hygiene routine. The use of a toothbrush and an interproximal cleaning method may not be enough to control dental plaque. Essential oils and delmopinol mouth rinses are effective for the prevention of dental caries and gingivitis. To study the effect of an essential oil and a delmopinol mouth rinse on dental plaque bacteria, an in vitro study was developed. The objective of this study was to determine the antibacterial activity of an essential oil and a delmopinol mouth rinse on Streptococcus mutans, Lactobacilli, and aerobic and anaerobic dental plaque nonspecific bacteria. Samples of human dental plaque were collected from consenting participants and bacteria isolated. Disk-diffusion tests were performed to obtain the minimum concentration of the mouth rinses necessary to inhibit bacterial growth. The ability of the commercial mouth rinses to inhibit bacterial growth was studied in comparison to a positive control (0.2% chlorhexidine) and a negative laboratorial control (sterilized water). The minimum inhibitory concentration was found to be inferior to the commercial essential oils and delmopinol mouth rinses concentrations. Delmopinol and essential oils have significant antibacterial properties shown in vitro only for aerobic bacteria, and for S. mutans, Lactobacillus, and anaerobic bacteria, the results were not statistically significant. Essential oils and chlorhexidine are statistically similar and better than delmopinol for aerobic bacteria growth inhibition. For the other bacteria, essential oils and delmopinol are not statistically promising. Results show that essential oils only may help patients to maintain good oral health as a complement to daily brushing and interproximal cleaning.

  14. Estimates of Nutrient Loading by Ground-Water Discharge into the Lynch Cove Area of Hood Canal, Washington

    Science.gov (United States)

    Simonds, F. William; Swarzenski, Peter W.; Rosenberry, Donald O.; Reich, Christopher D.; Paulson, Anthony J.

    2008-01-01

    Low dissolved oxygen concentrations in the waters of Hood Canal threaten marine life in late summer and early autumn. Oxygen depletion in the deep layers and landward reaches of the canal is caused by decomposition of excess phytoplankton biomass, which feeds on nutrients (primarily nitrogen compounds) that enter the canal from various sources, along with stratification of the water column that prevents mixing and replenishment of oxygen. Although seawater entering the canal is the largest source of nitrogen, ground-water discharge to the canal also contributes significant quantities, particularly during summer months when phytoplankton growth is most sensitive to nutrient availability. Quantifying ground-water derived nutrient loads entering an ecologically sensitive system such as Hood Canal is a critical component of constraining the total nutrient budget and ultimately implementing effective management strategies to reduce impacts of eutrophication. The amount of nutrients entering Hood Canal from ground water was estimated using traditional and indirect measurements of ground-water discharge, and analysis of nutrient concentrations. Ground-water discharge to Hood Canal is variable in space and time because of local geology, variable hydraulic gradients in the ground-water system adjacent to the shoreline, and a large tidal range of 3 to 5 meters. Intensive studies of ground-water seepage and hydraulic-head gradients in the shallow, nearshore areas were used to quantify the freshwater component of submarine ground-water discharge (SGD), whereas indirect methods using radon and radium geochemical tracers helped quantify total SGD and recirculated seawater. In areas with confirmed ground-water discharge, shore-perpendicular electrical resistivity profiles, continuous electromagnetic seepage-meter measurements, and continuous radon measurements were used to visualize temporal variations in ground-water discharge over several tidal cycles. The results of these

  15. THE 2003 -2007 MINIMUM, MAXIMUM AND MEDIUM DISCHARGE ANALYSIS OF THE LATORIŢA-LOTRU WATER SYSTEM

    Directory of Open Access Journals (Sweden)

    Simona-Elena MIHĂESCU

    2010-06-01

    Full Text Available The 2003 -2007 minimum, maximum and medium discharge analysis of the Latoriţa-Lotru water system From a functional point of view, the Lotru and Latoriţa make up a water system by the junction of the two high hydro energetic potential water flows. The Lotru springs from the Parâng Massif with a spring quota of over 1900m and an outfall quota of 298m, which makes for an altitude difference of 1602m; it is the affluent of the Olt River, has a course length of 76 km and a minimum discharge of 20m3/s. Its reception hollow is of 1024 km2. Latoriţa springs from the Latoriţa Mountains, it is a small river with an average discharge of 2.7m3/s and is an affluent of the Lotru. Together, the two make up a high hydro energetic potential system, valorized in the system of lakes which serve the Ciunget Hydro-Electric Power Plant. Galbenu and Petrimanu are two reservoirs built on the Latoriţa River and on the Lotru, we have Vidra reservoir, Balindru, Mălaia and Brădişor. The discharge analysis of these rivers is very important in view of a good risk management, especially consisting in floods and high level waters, even in the case of artificial water flows such as the Latoriţa-Lotru water system.

  16. Effectiveness of immediate bonding of etch-and-rinse adhesives to simplified ethanol-saturated dentin

    Directory of Open Access Journals (Sweden)

    Leandro Afonso Guimarães

    2012-04-01

    Full Text Available This study examined the immediate bond strength of etch-and-rinse adhesives to demineralized dentin saturated with either water or absolute ethanol. The research hypothesis was that there would be no difference in bond strength to dentin between water or ethanol wet-bonding techniques. The medium dentin of 20 third molars was exposed (n = 5. The dentin surface was then acid-etched, left moist and randomly assigned to be saturated via either water wet-bonding (WBT or absolute ethanol wet-bonding (EBT. The specimens were then treated with one of the following etch-and-rinse adhesive systems: a 3-step, water-based system (Adper Scotchbond Multipurpose, or SBMP or a 2-step, ethanol/water-based system (Adper Single Bond 2, or SB. Resin composite build-ups were then incrementally constructed. After water storage for 24 h at 37°C, the tensile strength of the specimens was tested in a universal testing machine (0.5 mm/min. Data were analyzed by two-way ANOVA and Tukey's test (a = 5%. The failure modes were verified using a stereomicroscope (40'. For both adhesives, no significant difference in bond strength was observed between WBT and EBT (p > 0.05. The highest bond strength was observed for SB, regardless of the bonding technique (p < 0.05. No significant interaction between adhesives and bonding techniques was noticed (p = 0.597. There was a predominance of adhesive failures for all tested groups. The EBT and WBT displayed similar immediate bond strength means for both adhesives. The SB adhesive exhibited higher means for all conditions tested. Further investigations are needed to evaluate long-term bonding to dentin mediated by commercial etch-and-rinse adhesives using the EBT approach.

  17. Identification of significant pressures and assessment of wastewater discharge on Krivaja River water quality

    Directory of Open Access Journals (Sweden)

    Pešić Vesna Z.

    2017-01-01

    Full Text Available One of the key stages of the process of preparing management plans for the river basin is the analysis of pressures and impacts, as well as the risk assessment of failing to achieve the environmental objectives. DPSIR framework (Driving Forces-Pressure-State-Impact-Response was developed by the European Agency for the environmental protection, and makes the conceptual basis for the pressures and impacts analysis, taking into account the complexity of the interactions in the environment and represents the tool for their analysis. Impact assessment of the water body requires some quantitative information to describe the condition of the water body and/or the pressures that act on it. The aim of the study was to determine the effect of wastewater discharge on Krivaja watercourse. Impact assessment is carried out based on data of polluters’ wastewater and monitoring information for water in Krivaja. For each site at which sampling was performed, the specific risk quotients for surface water were calculated, as the ratio of the each pollutant concentration in surface water at the sampling point and environmental quality standards for pollutants, as well as their sum that represents the risk index. In order to have the integrated perceive of processes in the Krivaja River, taking into account cumulative effects from point sources, the concept of total maximum daily load was applied, using which the pollution amount, that can be discharged daily in a water body without degrading his prescribed/required quality, was calculated. Comparison of emitted loads from pollution point sources with maximum allowable ones was performed. Wastewaters of different polluters located on Krivaja are, due to insufficient treatment, very loaded with organic matter and nutrients. Krivaja receives daily 1332 m3 of wastewater, 999 kg COD, 722 kg BOD, 144 kg of nitrogen, 4.3 kg of phosphorus and 627 kg of suspended solids. Of the total wastewater volume, the majority (69

  18. Application of Tank Model for Predicting Water Balance and Flow Discharge Components of Cisadane Upper Catchment

    Directory of Open Access Journals (Sweden)

    Nana Mulyana Arifjaya

    2012-01-01

    Full Text Available The concept of hydrological tank model was well described into four compartments (tanks. The first tank (tank A comprised of one vertical (qA0 and two lateral (qA1 and qA2 water flow components and tank B comprised of one vertical (qB0 and one lateral (qB1 water flow components. Tank C comprised of one vertical (qC0 and one lateral (qC1 water flow components, whereas tank D comprised of one lateral water flow component (qD1.  These vertical water flows would also contribute to the depletion of water flow in the related tanks but would replenish tanks in the deeper layers. It was assumed that at all lateral water flow components would finally accumulate in one stream, summing-up of the lateral water flow, much or less, should be equal to the water discharge (Qo at specified time concerns. Tank A received precipitation (R and evapo-transpiration (ET which was its gradientof (R-ET over time would become the driving force for the changes of water stored in the soil profiles and thosewater flows leaving the soil layer.  Thus tank model could describe th vertical and horizontal water flow withinthe watershed. The research site was Cisadane Upper Catchment, located at Pasir Buncir Village of CaringinSub-District within the Regency of Bogor in West Java Province.  The elevations ranged 512 –2,235 m above sealevel, with a total drainage area of 1,811.5 ha and total length of main stream of 14,340.7 m.  The land cover wasdominated by  forest  with a total of 1,044.6 ha (57.67%,  upland agriculture with a total of 477.96 ha (26.38%,mixed garden with a total of 92.85 ha(5.13% and semitechnical irigated rice field with a total of 196.09 ha (10,8%.  The soil was classified as hydraquent (96.6% and distropept (3.4%.  Based on the calibration of tank model application in the study area, the resulting coefficient of determination (R2 was 0.72 with model efficiency (NSEof= 0.75, thus tank model could well illustrate the water flow distribution of

  19. Oral Topical Doxepin Rinse: Anesthetic Effect in Normal Subjects

    Directory of Open Access Journals (Sweden)

    Joel B Epstein

    2003-01-01

    Full Text Available Oral doxepin rinse has been reported to provide pain relief in patients with oral mucosal lesions due to cancer or cancer therapy. The purpose of this study was to assess the anesthetic effect of doxepin oral rinse in normal subjects to identify the duration of effect and to contrast the anesthetic effect with reported pain relief in patients with oral mucosal lesions. Normal volunteers were provided a solution of doxepin (5 mg/mL for oral rinsing. Oral numbness and adverse effects were recorded for a period of 4 h after rinsing. Doxepin rinse resulted in mucosal anesthesia in all subjects. Sedation/fatigue was reported in four of seven subjects. There were no taste complaints and no nausea reported. The limited duration of numbness/anesthesia in normal subjects compared with prior studies showing pain relief for more than 3 h in patients with mucosal lesions, suggests that the extended duration of pain relief in patients was due to analgesic effects rather than anesthetic effects. The majority of normal subjects reported sedation after use, but this was less common in patients with mucosal lesions.

  20. Entrapment investigations of water-droplet behavior in a hot tin melt with varying discharge velocities and orifices

    International Nuclear Information System (INIS)

    Froehlich, G.; Mueller, K.

    1983-10-01

    Experiments were performed in which water was pressed through a thermally isolated tube into a clyindrical crucible (diameter 5 cm, height 7,5 cm both measured inside) filled with molten tin (600 K). The diameter of the circular water outlet was varied from 0.5 up to 10 mm and the discharge velocity of the water was in the range of 0.05 up to 20 m/s. In the tin melt the water divides into single drops, which emerged on the melt surface, if an interaction between water and tin melt did not occur. The probability for an interaction increased in experiments with higher discharge velocities of the water and smaller diameters of the water outlet. In experiments with discharge velocities ≥ 5 m/s and outlet diameters ≤ 2 mm one or more interactions occured in each case. At these interactions of water drops entrapped in the tin melt (called entrapment interactions) a portion of the melt was ejected from the crucible. The moment of the interaction and the pulse of the force toward the crucible bottom were recorded. (orig.) [de

  1. Potential water-quality effects of coal-bed methane production water discharged along the upper Tongue River, Wyoming and Montana

    Science.gov (United States)

    Kinsey, Stacy M.; Nimick, David A.

    2011-01-01

    Water quality in the upper Tongue River from Monarch, Wyoming, downstream to just upstream from the Tongue River Reservoir in Montana potentially could be affected by discharge of coal-bed methane (CBM) production water (hereinafter referred to as CBM discharge). CBM discharge typically contains high concentrations of sodium and other ions that could increase dissolved-solids (salt) concentrations, specific conductance (SC), and sodium-adsorption ratio (SAR) in the river. Increased inputs of sodium and other ions have the potential to alter the river's suitability for agricultural irrigation and aquatic ecosystems. Data from two large tributaries, Goose Creek and Prairie Dog Creek, indicate that these tributaries were large contributors to the increase in SC and SAR in the Tongue River. However, water-quality data were not available for most of the smaller inflows, such as small tributaries, irrigation-return flows, and CBM discharges. Thus, effects of these inflows on the water quality of the Tongue River were not well documented. Effects of these small inflows might be subtle and difficult to determine without more extensive data collection to describe spatial patterns. Therefore, synoptic water-quality sampling trips were conducted in September 2005 and April 2006 to provide a spatially detailed profile of the downstream changes in water quality in this reach of the Tongue River. The purpose of this report is to describe these downstream changes in water quality and to estimate the potential water-quality effects of CBM discharge in the upper Tongue River. Specific conductance of the Tongue River through the study reach increased from 420 to 625 microsiemens per centimeter (.μS/cm; or 49 percent) in the downstream direction in September 2005 and from 373 to 543 .μS/cm (46 percent) in April 2006. Large increases (12 to 24 percent) were measured immediately downstream from Goose Creek and Prairie Dog Creek during both sampling trips. Increases attributed to

  2. The hydrological function of upland swamps in eastern Australia: The role of geomorphic condition in regulating water storage and discharge

    Science.gov (United States)

    Cowley, Kirsten L.; Fryirs, Kirstie A.; Hose, Grant C.

    2018-06-01

    Temperate Highland Peat Swamps on Sandstone (THPSS) are a type of wetland found in low-order streams on the plateaus of eastern Australia. They are sediment and organic matter accumulation zones, which combined with a climate of high rainfall and low evaporation function as water storage systems. Changes to the geomorphic structure of these systems via incision and channelisation can have profound impacts on their hydrological function. The aim of this study was to develop an understanding of how changes to the geomorphic structure of these systems alter their hydrological function, measured as changes and variability in swamp water table levels and discharge. We monitored the water table levels and discharges of three intact and three channelised THPSS in the Blue Mountains between March 2015 and June 2016. We found that water levels in intact swamps were largely stable over the monitoring period. Water levels rose only in high rainfall events, returned quickly to antecedent levels after rain, and drawdown during dry periods was not significant. In contrast, the water table levels in channelised THPSS were highly variable. Water levels rose quickly after almost all rainfall events and declined significantly during dry periods. Discharge also showed marked differences with the channelised THPSS discharging 13 times more water than intact swamps, even during dry periods. Channelised THPSS also had flashier storm hydrographs than intact swamps. These results have profound implications for the capacity of these swamps to act as water storage reservoirs in the headwaters of catchments and for their ability to maintain base flow to downstream catchments during dry times. Changes to geomorphic structure and hydrological function also have important implications for a range of other swamp functions such as carbon storage, emission and exports, contaminant sorption, downstream water quality and biodiversity, as well as the overall fate of these swamps under a changing

  3. Goodenough Spring, Texas, USA: Discharge and water chemistry of a large spring deeply submerged under the binational Amistad Reservoir

    Science.gov (United States)

    Kamps, Ray H.; Tatum, Gregg S.; Gault, Mike; Groeger, Alan W.

    2009-06-01

    Goodenough Spring (Texas, USA) is a large spring near the border of the American state of Texas and the Mexican state of Coahuila, discharging into the international Amistad Reservoir on the river Rio Grande (Rio Bravo). Discharge was routinely measured from 1928 until 1968 to partition the flow of the river between the two countries in accordance with water-use treaties. Samples were analyzed for water-quality parameters in 1967-1968 prior to inundation under 45 m of Amistad Reservoir in 1968. Subsequently, discharge has been estimated indirectly by the International Boundary and Water Commission (IBWC). For the first direct measurements of the spring in 37 years, velocity and cross-sectional measurements were made and water samples collected in the summer of 2005 using advanced self-contained underwater breathing apparatus (SCUBA) techniques. Spring discharge was calculated at 2.03 m3 s-1, approximately one-half of the historical mean of 3.94 m3 s-1. In situ and laboratory analyses of samples for temperature, pH, dissolved oxygen, specific conductance, alkalinity, nitrate-nitrogen, dissolved solids, chloride, sulfate, fluoride, phosphorus, calcium, sodium, potassium, magnesium, and iron showed the water quality to be very good for human consumption and crop irrigation. Measurement values are relatively unchanged from those reported 37 years prior.

  4. Destruction of 4-phenolsulfonic acid in water by anodic contact glow discharge electrolysis.

    Science.gov (United States)

    Yang, Haiming; An, Baigang; Wang, Shaoyan; Li, Lixiang; Jin, Wenjie; Li, Lihua

    2013-06-01

    Destruction of 4-phenolsulfonic acid (4-PSA) in water was carried out using anodic contact glow discharge electrolysis. Accompanying the decay of 4-PSA, the amount of total organic carbon (TOC) in water correspondingly decreased, while the sulfonate group of 4-PSA was released as sulfate ion. Oxalate and formate were obtained as minor by-products. Additionally, phenol, 1,4-hydroquinone, hydroxyquinol and 1,4-benzoquinone were detected as primary intermediates in the initial stages of decomposition of 4-PSA. A reaction pathway involving successive attacks of hydroxyl and hydrogen radicals was assumed on the basis of the observed products and kinetics. It was revealed that the decay of both 4-PSA and TOC obeyed a first-order rate law. The effects of different Fe ions and initial concentrations of 4-PSA on the degradation rate were investigated. It was found that the presence of Fe ions could increase the degradation rate of 4-PSA, while initial concentrations lower than 80 mmol/L had no significant effect on kinetic behaviour. The disappearance rate of 4-PSA was significantly affected by pH.

  5. Inactivation of Escherichia coli in water by pulsed dielectric barrier discharge in coaxial reactor.

    Science.gov (United States)

    Hernández-Arias, A N; Rodríguez-Méndez, B G; López-Callejas, R; Alcántara-Díaz, D; Valencia-Alvarado, R; Mercado-Cabrera, A; Peña-Eguiluz, R; Muñoz-Castro, A E; Barocio, S R; de la Piedad-Beneitez, A

    2012-09-01

    An experimental study of ATCC (American Type Culture Collection) 8739 Escherichia coli bacteria inactivation in water by means of pulsed dielectric barrier discharge (PDBD) atmospheric pressure plasmas is presented. Plasma is generated by an adjustable power source capable of supplying high voltage 25 kV pulses, ∼30 μs long and at a 500 Hz frequency. The process was conducted in a ∼152 cm(3) cylindrical stainless steel coaxial reactor, endowed with a straight central electrode and a gas inlet. The bacterial concentration in water was varied from 10(3) up to 10(8) E. coli cells per millilitre. The inactivation was achieved without gas flow in the order of 82% at 10(8) colony-forming units per millilitre (CFU mL(-1)) concentrations in 600 s. In addition, oxygen was added to the gas supply in order to increase the ozone content in the process, raising the inactivation percentage to the order of 90% in the same treatment time. In order to reach a higher efficiency however, oxygen injection modulation is applied, leading to inactivation percentages above 99.99%. These results are similarly valid for lower bacterial concentrations.

  6. Review of research on impacts to biota of discharges of naturally occurring radionuclides in produced water to the marine environment

    International Nuclear Information System (INIS)

    Hosseini, Ali; Brown, Justin E.; Gwynn, Justin P.; Dowdall, Mark

    2012-01-01

    Produced water has been described as the largest volume waste stream in the exploration and production process of oil and gas. It is accompanied by discharges of naturally occurring radionuclides raising concerns over the potential radiological impacts of produced water on marine biota. In the Northern European marine environment, radioactivity in produced water has received substantial attention owing to the OSPAR Radioactive Substances Strategy which aims at achieving ‘concentrations in the environment near background values for naturally occurring radioactive substances’. This review provides an overview of published research on the impacts to biota from naturally occurring radionuclides discharged in produced water by the offshore oil and gas industry. In addition to summarising studies and data that deal directly with the issue of dose and effect, the review also considers studies related to the impact of added chemicals on the fate of discharged radionuclides. The review clearly illustrates that only a limited number of studies have investigated possible impacts on biota from naturally occurring radionuclides present in produced water. Hence, although these studies indicate that the risk to the environment from naturally occurring radionuclides discharged in produced water is negligible, the substantial uncertainties involved in the assessments of impact make it difficult to be conclusive. With regard to the complexity involved in the problem under consideration there is a pressing need to supplement existing data and acquire new knowledge. Finally, the present work identifies some knowledge gaps to indicate future research requirements. -- Highlights: ► Produced water from offshore oil industry contains naturally occurring radionuclides. ► Published research on the impacts to biota from these radionuclides is reviewed. ► Review includes impact of added chemicals on the fate of discharged radionuclides. ► Studies indicate negligible risk to biota

  7. Chemical vs. herbal formulations as pre-procedural mouth rinses to combat aerosol production: A randomized controlled study

    Directory of Open Access Journals (Sweden)

    Koduganti Rekha Rani

    2014-01-01

    Full Text Available Background: Disease transmission and barrier techniques are the key concerns during ultrasonic instrumentation as this procedure has the hazard of aerosol production which has a multitude of deleterious effects on the body. The aerosol produced can affect both the patient and the clinician. The aim of this study was to assess the importance of pre-procedural rinsing before scaling by ultrasonic instrumentation and to compare the efficacy of commercially available herbal mouth rinse and a Chlorhexidine gluconate mouth rinse with a control group. The study was conducted from 1 st February to 15 th April 2012 in a tertiary referral care hospital. The study was approved by the institutional ethical committee. This was a randomized single blinded interventional study, where in 36 patients equally divided into three groups participated. Material and Methods: Thirty six patients were recruited in this study aged between 18-35 years. All patients had plaque index scores between1.5-3.0, and were categorized into three groups. Patients with systemic diseases and on antibiotic therapy were excluded. Group A or control group underwent scaling with water as pre-procedural rinse, Group B used 20 ml of 0.2% Chlorhexidine and group C were administered 18 ml of a herbal pre-procedural rinse. Aerosol splatter produced during the procedure were collected on blood agar plates and sent for microbiologic analysis for the assessment of bacterial Colony Forming Units (CFUs. The mean CFUs and standard deviation (SD for each group were measured. Post hoc test was used to compare the differences between three groups, Control (A Chlorhexidine (B and Herbal (C. Results: The mean Colony Forming Units (CFUs for control group was 114.50, Chlorhexidine group was 56.75 and herbal rinse group was 47.38. Conclusion: Pre-procedural rinsing was found to be effective in reducing aerosol contamination during ultrasonic scaling though no statistically significant difference was found

  8. Ground-water discharge determined from measurements of evapotranspiration, other available hydrologic components, and shallow water-level changes, Oasis Valley, Nye County, Nevada

    International Nuclear Information System (INIS)

    Reiner, S.R.; Laczniak, R.J.; DeMeo, G.A.; Smith LaRue, J.; Elliott, P.E.; Nylund, W.E.; Fridrich, C.J.

    2002-01-01

    Oasis Valley is an area of natural ground-water discharge within the Death Valley regional ground-water flow system of southern Nevada and adjacent California. Ground water discharging at Oasis Valley is replenished from inflow derived from an extensive recharge area that includes the northwestern part of the Nevada Test Site (NTS). Because nuclear testing has introduced radionuclides into the subsurface of the NTS, the U.S. Department of Energy currently is investigating the potential transport of these radionuclides by ground water flow. To better evaluate any potential risk associated with these test-generated contaminants, a number of studies were undertaken to accurately quantify discharge from areas downgradient in the regional ground-water flow system from the NTS. This report refines the estimate of ground-water discharge from Oasis Valley. Ground-water discharge from Oasis Valley was estimated by quantifying evapotranspiration (ET), estimating subsurface outflow, and compiling ground-water withdrawal data. ET was quantified by identifying areas of ongoing ground-water ET, delineating areas of ET defined on the basis of similarities in vegetation and soil-moisture conditions and computing ET rates for each of the delineated areas. A classification technique using spectral-reflectance characteristics determined from satellite imagery acquired in 1992 identified eight unique areas of ground-water ET. These areas encompass about 3,426 acres of sparsely to densely vegetated grassland, shrubland, wetland, and open water. Annual ET rates in Oasis Valley were computed with energy-budget methods using micrometeorological data collected at five sites. ET rates range from 0.6 foot per year in a sparse, dry saltgrass environment to 3.1 feet per year in dense meadow vegetation. Mean annual ET from Oasis Valley is estimated to be about 7,800 acre-feet. Mean annual ground-water discharge by ET from Oasis Valley, determined by removing the annual local precipitation

  9. Validation of a hot water rinse and lactic acid spray in combination with scaling for treating hide-on carcasses to control biotype I strains of Escherichia coli used as surrogates for Shiga toxin-producing E. coli

    Science.gov (United States)

    Scalding of hide-on bob veal carcasses with or without standard scalding chemical agents typically used for hogs, followed by an 82.2degreeC hot water wash and lactic acid spray (applied at ambient temperature) prior to chilling, was evaluated to determine its effectiveness in reducing the levels of...

  10. Developing a methodology for real-time trading of water withdrawal and waste load discharge permits in rivers.

    Science.gov (United States)

    Soltani, Maryam; Kerachian, Reza

    2018-04-15

    In this paper, a new methodology is proposed for the real-time trading of water withdrawal and waste load discharge permits in agricultural areas along the rivers. Total Dissolved Solids (TDS) is chosen as an indicator of river water quality and the TDS load that agricultural water users discharge to the river are controlled by storing a part of return flows in some evaporation ponds. Available surface water withdrawal and waste load discharge permits are determined using a non-linear multi-objective optimization model. Total available permits are then fairly reallocated among agricultural water users, proportional to their arable lands. Water users can trade their water withdrawal and waste load discharge permits simultaneously, in a bilateral, step by step framework, which takes advantage of differences in their water use efficiencies and agricultural return flow rates. A trade that would take place at each time step results in either more benefit or less diverted return flow. The Nucleolus cooperative game is used to redistribute the benefits generated through trades in different time steps. The proposed methodology is applied to PayePol region in the Karkheh River catchment, southwest Iran. Predicting that 1922.7 Million Cubic Meters (MCM) of annual flow is available to agricultural lands at the beginning of the cultivation year, the real-time optimization model estimates the total annual benefit to reach 46.07 million US Dollars (USD), which requires 6.31 MCM of return flow to be diverted to the evaporation ponds. Fair reallocation of the permits, changes these values to 35.38 million USD and 13.69 MCM, respectively. Results illustrate the effectiveness of the proposed methodology in the real-time water and waste load allocation and simultaneous trading of permits. Copyright © 2018 Elsevier Ltd. All rights reserved.

  11. Longevity of Self-etch Dentin Bonding Adhesives Compared to Etch-and-rinse Dentin Bonding Adhesives: A Systematic Review.

    Science.gov (United States)

    Masarwa, Nader; Mohamed, Ahmed; Abou-Rabii, Iyad; Abu Zaghlan, Rawan; Steier, Liviu

    2016-06-01

    A systematic review and meta-analysis were performed to compare longevity of Self-Etch Dentin Bonding Adhesives to Etch-and-Rinse Dentin Bonding Adhesives. The following databases were searched for PubMed, MEDLINE, Web of Science, CINAHL, the Cochrane Library complemented by a manual search of the Journal of Adhesive Dentistry. The MESH keywords used were: "etch and rinse," "total etch," "self-etch," "dentin bonding agent," "bond durability," and "bond degradation." Included were in-vitro experimental studies performed on human dental tissues of sound tooth structure origin. The examined Self-Etch Bonds were of two subtypes; Two Steps and One Step Self-Etch Bonds, while Etch-and-Rinse Bonds were of two subtypes; Two Steps and Three Steps. The included studies measured micro tensile bond strength (μTBs) to evaluate bond strength and possible longevity of both types of dental adhesives at different times. The selected studies depended on water storage as the aging technique. Statistical analysis was performed for outcome measurements compared at 24 h, 3 months, 6 months and 12 months of water storage. After 24 hours (p-value = 0.051), 3 months (p-value = 0.756), 6 months (p-value=0.267), 12 months (p-value=0.785) of water storage self-etch adhesives showed lower μTBs when compared to the etch-and-rinse adhesives, but the comparisons were statistically insignificant. In this study, longevity of Dentin Bonds was related to the measured μTBs. Although Etch-and-Rinse bonds showed higher values at all times, the meta-analysis found no difference in longevity of the two types of bonds at the examined aging times. Copyright © 2016 Elsevier Inc. All rights reserved.

  12. Increasing the effectiveness of purification of wash water discharge during placer mining. Povyshenie effekitivnosti ochistki promstokov pri razrabotke rossypei

    Energy Technology Data Exchange (ETDEWEB)

    Volkova, V M; Matveev, A A

    1981-01-01

    In the book research results are generalized for processes of water supply and purification of wash water discharges from dredge mining of placer deposits. Aspects of the geological and mineralogical structure of the solid phase of dredge waste waters and regularities in its influence on the sedimentation capacity of the suspended matter are examined. On the basis of a study of distinctive features in the hydrodynamic processes occurring in dredge sludge-settling tanks, a method is proposed for calculation of the settling tank parameters, allowing their areas of application for wash water discharge clarification to be determined reliably. Results are reported for a study of methods of intensification of the deposition of suspended clay particles in dredge waste waters, (methods) based on the use of both a series of coagulants and flocculants producible by industry and various production wastes. Aspects of the theory and practice of organizing circulating water supply for dredges are examined. The influence of wash water discharges forming during placer mining on the environment is assessed.

  13. Tracking stormwater discharge plumes and water quality of the Tijuana River with multispectral aerial imagery

    Science.gov (United States)

    Svejkovsky, Jan; Nezlin, Nikolay P.; Mustain, Neomi M.; Kum, Jamie B.

    2010-04-01

    Spatial-temporal characteristics and environmental factors regulating the behavior of stormwater runoff from the Tijuana River in southern California were analyzed utilizing very high resolution aerial imagery, and time-coincident environmental and bacterial sampling data. Thirty nine multispectral aerial images with 2.1-m spatial resolution were collected after major rainstorms during 2003-2008. Utilizing differences in color reflectance characteristics, the ocean surface was classified into non-plume waters and three components of the runoff plume reflecting differences in age and suspended sediment concentrations. Tijuana River discharge rate was the primary factor regulating the size of the freshest plume component and its shorelong extensions to the north and south. Wave direction was found to affect the shorelong distribution of the shoreline-connected fresh plume components much more strongly than wind direction. Wave-driven sediment resuspension also significantly contributed to the size of the oldest plume component. Surf zone bacterial samples collected near the time of each image acquisition were used to evaluate the contamination characteristics of each plume component. The bacterial contamination of the freshest plume waters was very high (100% of surf zone samples exceeded California standards), but the oldest plume areas were heterogeneous, including both polluted and clean waters. The aerial imagery archive allowed study of river runoff characteristics on a plume component level, not previously done with coarser satellite images. Our findings suggest that high resolution imaging can quickly identify the spatial extents of the most polluted runoff but cannot be relied upon to always identify the entire polluted area. Our results also indicate that wave-driven transport is important in distributing the most contaminated plume areas along the shoreline.

  14. Impact of Submarine Groundwater Discharge on Marine Water Quality and Reef Biota of Maui.

    Directory of Open Access Journals (Sweden)

    Daniel W Amato

    Full Text Available Generally unseen and infrequently measured, submarine groundwater discharge (SGD can transport potentially large loads of nutrients and other land-based contaminants to coastal ecosystems. To examine this linkage we employed algal bioassays, benthic community analysis, and geochemical methods to examine water quality and community parameters of nearshore reefs adjacent to a variety of potential, land-based nutrient sources on Maui. Three common reef algae, Acanthophora spicifera, Hypnea musciformis, and Ulva spp. were collected and/or deployed at six locations with SGD. Algal tissue nitrogen (N parameters (δ15N, N %, and C:N were compared with nutrient and δ15N-nitrate values of coastal groundwater and nearshore surface water at all locations. Benthic community composition was estimated for ten 10-m transects per location. Reefs adjacent to sugarcane farms had the greatest abundance of macroalgae, low species diversity, and the highest concentrations of N in algal tissues, coastal groundwater, and marine surface waters compared to locations with low anthropogenic impact. Based on δ15N values of algal tissues, we estimate ca. 0.31 km2 of Kahului Bay is impacted by effluent injected underground at the Kahului Wastewater Reclamation Facility (WRF; this region is barren of corals and almost entirely dominated by colonial zoanthids. Significant correlations among parameters of algal tissue N with adjacent surface and coastal groundwater N indicate that these bioassays provided a useful measure of nutrient source and loading. A conceptual model that uses Ulva spp. tissue δ15N and N % to identify potential N source(s and relative N loading is proposed for Hawai'i. These results indicate that SGD can be a significant transport pathway for land-based nutrients with important biogeochemical and ecological implications in tropical, oceanic islands.

  15. Impact of Submarine Groundwater Discharge on Marine Water Quality and Reef Biota of Maui.

    Science.gov (United States)

    Amato, Daniel W; Bishop, James M; Glenn, Craig R; Dulai, Henrietta; Smith, Celia M

    2016-01-01

    Generally unseen and infrequently measured, submarine groundwater discharge (SGD) can transport potentially large loads of nutrients and other land-based contaminants to coastal ecosystems. To examine this linkage we employed algal bioassays, benthic community analysis, and geochemical methods to examine water quality and community parameters of nearshore reefs adjacent to a variety of potential, land-based nutrient sources on Maui. Three common reef algae, Acanthophora spicifera, Hypnea musciformis, and Ulva spp. were collected and/or deployed at six locations with SGD. Algal tissue nitrogen (N) parameters (δ15N, N %, and C:N) were compared with nutrient and δ15N-nitrate values of coastal groundwater and nearshore surface water at all locations. Benthic community composition was estimated for ten 10-m transects per location. Reefs adjacent to sugarcane farms had the greatest abundance of macroalgae, low species diversity, and the highest concentrations of N in algal tissues, coastal groundwater, and marine surface waters compared to locations with low anthropogenic impact. Based on δ15N values of algal tissues, we estimate ca. 0.31 km2 of Kahului Bay is impacted by effluent injected underground at the Kahului Wastewater Reclamation Facility (WRF); this region is barren of corals and almost entirely dominated by colonial zoanthids. Significant correlations among parameters of algal tissue N with adjacent surface and coastal groundwater N indicate that these bioassays provided a useful measure of nutrient source and loading. A conceptual model that uses Ulva spp. tissue δ15N and N % to identify potential N source(s) and relative N loading is proposed for Hawai'i. These results indicate that SGD can be a significant transport pathway for land-based nutrients with important biogeochemical and ecological implications in tropical, oceanic islands.

  16. Research on the discharge characteristics for water tree in crosslinked polyethylene cable based on plasma-chemical model

    Science.gov (United States)

    Fan, Yang; Qi, Yang; Bing, Gao; Rong, Xia; Yanjie, Le; Iroegbu, Paul Ikechukwu

    2018-03-01

    Water tree is the predominant defect in high-voltage crosslinked polyethylene cables. The microscopic mechanism in the discharge process is not fully understood; hence, a drawback is created towards an effective method to evaluate the insulation status. In order to investigate the growth of water tree, a plasma-chemical model is developed. The dynamic characteristics of the discharge process including voltage waveform, current waveform, electron density, electric potential, and electric field intensity are analyzed. Our results show that the distorted electric field is the predominant contributing factor of electron avalanche formation, which inevitably leads to the formation of pulse current. In addition, it is found that characteristic parameters such as the pulse width and pulse number have a great relevance to the length of water tree. Accordingly, the growth of water tree can be divided into the initial stage, development stage, and pre-breakdown stage, which provides a reference for evaluating the deteriorated stages of crosslinked polyethylene cables.

  17. Treatment of discharge water from hydrostatic testing of natural gas pipelines. Volume 4. Topical report, January 1989-June 1992

    International Nuclear Information System (INIS)

    Tallon, J.T.; Lee-Ryan, P.B.; Volpi, K.A.; Fillo, J.P.

    1992-06-01

    The report presents results developed from bench- and full-scale treatment testing conducted on discharge water from hydrostatic testing of natural gas pipelines. Bench-scale testing examined sedimentation with and without chemical coagulants for reducing iron and total suspended solids, aeration for removal of volatile organics, and activated carbon adsorption for removal of organic constituents. Treatment results are provided for a full-scale treatment process, which utilized a hay bale structure and adsorbent booms for removing suspended solids and oil from the discharge water. Detailed characterization results are presented for test water collected before and after treatment. Results developed from an economic analysis of other potential treatment/disposal alternatives are also presented. A total of eight approaches that may be applied for managing constituents present in hydrostatic test waters are examined. The report is Volume 4 of a five-volume report series

  18. Satellite Derived Water Quality Observations Are Related to River Discharge and Nitrogen Loads in Pensacola Bay, Florida

    OpenAIRE

    John C. Lehrter; John C. Lehrter; Chengfeng Le

    2017-01-01

    Relationships between satellite-derived water quality variables and river discharges, concentrations and loads of nutrients, organic carbon, and sediments were investigated over a 9-year period (2003–2011) in Pensacola Bay, Florida, USA. These analyses were conducted to better understand which river forcing factors were the primary drivers of estuarine variability in several water quality variables. Remote sensing reflectance time-series data were retrieved from the MEdium Resolution Imaging ...

  19. Surface Water Modeling Using an EPA Computer Code for Tritiated Waste Water Discharge from the heavy Water Facility

    International Nuclear Information System (INIS)

    Chen, K.F.

    1998-06-01

    Tritium releases from the D-Area Heavy Water Facilities to the Savannah River have been analyzed. The U.S. EPA WASP5 computer code was used to simulate surface water transport for tritium releases from the D-Area Drum Wash, Rework, and DW facilities. The WASP5 model was qualified with the 1993 tritium measurements at U.S. Highway 301. At the maximum tritiated waste water concentrations, the calculated tritium concentration in the Savannah River at U.S. Highway 301 due to concurrent releases from D-Area Heavy Water Facilities varies from 5.9 to 18.0 pCi/ml as a function of the operation conditions of these facilities. The calculated concentration becomes the lowest when the batch releases method for the Drum Wash Waste Tanks is adopted

  20. The effects of precipitation, river discharge, land use and coastal circulation on water quality in coastal Maine.

    Science.gov (United States)

    Tilburg, Charles E; Jordan, Linda M; Carlson, Amy E; Zeeman, Stephan I; Yund, Philip O

    2015-07-01

    Faecal pollution in stormwater, wastewater and direct run-off can carry zoonotic pathogens to streams, rivers and the ocean, reduce water quality, and affect both recreational and commercial fishing areas of the coastal ocean. Typically, the closure of beaches and commercial fishing areas is governed by the testing for the presence of faecal bacteria, which requires an 18-24 h period for sample incubation. As water quality can change during this testing period, the need for accurate and timely predictions of coastal water quality has become acute. In this study, we: (i) examine the relationship between water quality, precipitation and river discharge at several locations within the Gulf of Maine, and (ii) use multiple linear regression models based on readily obtainable hydrometeorological measurements to predict water quality events at five coastal locations. Analysis of a 12 year dataset revealed that high river discharge and/or precipitation events can lead to reduced water quality; however, the use of only these two parameters to predict water quality can result in a number of errors. Analysis of a higher frequency, 2 year study using multiple linear regression models revealed that precipitation, salinity, river discharge, winds, seasonality and coastal circulation correlate with variations in water quality. Although there has been extensive development of regression models for freshwater, this is one of the first attempts to create a mechanistic model to predict water quality in coastal marine waters. Model performance is similar to that of efforts in other regions, which have incorporated models into water resource managers' decisions, indicating that the use of a mechanistic model in coastal Maine is feasible.

  1. Forsmark site investigation. Monitoring of brook water levels, electrical conductivities, temperatures and discharges January-December 2009

    Energy Technology Data Exchange (ETDEWEB)

    Johansson, Per-Olof (Artesia Grundvattenkonsult (Sweden)); Juston, John (Juston Konsult (Sweden))

    2011-03-15

    This document reports the monitoring of water levels, electrical conductivities, temperatures and discharges at four brook discharge gauging stations, and the monitoring of water electrical conductivity at the outlet of Lake Bolundsfjaerden in the Forsmark area. The report presents data from 1 January through 31 December 2009 and is a continuation of reporting from Johansson and Juston (2007, 2009), which covered the periods from 1 April 2004 through 31 March 2007 and 1 April 2007 through 31 December 2008, respectively. Long-throated flumes equipped with automatically recording devices were used for the discharge measurements. Every c. 14 days the water depths at the upstream edge of the flumes were measured manually by a ruler as a check. Electrical conductivity and temperature were automatically recorded and these parameters were also measured manually every c. 14 days with the site investigation field devices. SKB's Hydro Monitoring System (HMS) was used to collect and store all data. From HMS quality assured data were transferred to SKB's primary database Sicada. Measurements of levels, electrical conductivities and temperatures were made every 10 minutes (every 30 minutes for electrical conductivity at the outlet of Lake Bolundsfjaerden). For the calculation of discharge, quality assured water level data from the flumes were used. The calculation procedure included consolidation of the time series to hourly averages, screening of data for removal of short-term spikes, noise and other data that were judged erroneous. After the calculations were performed, the results were delivered to Sicada. The amplitudes of water level variations during this reporting period were 0.26-0.33 m at the four stations. The mean electrical conductivities varied between 26 and 41 mS/m at the four discharge stations. The electrical conductivity at the outlet of Lake Bolundsfjaerden varied between 53 and 188 mS/m during the period with the higher values at the end of the

  2. Probability-based classifications for spatially characterizing the water temperatures and discharge rates of hot springs in the Tatun Volcanic Region, Taiwan.

    Science.gov (United States)

    Jang, Cheng-Shin

    2015-05-01

    Accurately classifying the spatial features of the water temperatures and discharge rates of hot springs is crucial for environmental resources use and management. This study spatially characterized classifications of the water temperatures and discharge rates of hot springs in the Tatun Volcanic Region of Northern Taiwan by using indicator kriging (IK). The water temperatures and discharge rates of the springs were first assigned to high, moderate, and low categories according to the two thresholds of the proposed spring classification criteria. IK was then used to model the occurrence probabilities of the water temperatures and discharge rates of the springs and probabilistically determine their categories. Finally, nine combinations were acquired from the probability-based classifications for the spatial features of the water temperatures and discharge rates of the springs. Moreover, various combinations of spring water features were examined according to seven subzones of spring use in the study region. The research results reveal that probability-based classifications using IK provide practicable insights related to propagating the uncertainty of classifications according to the spatial features of the water temperatures and discharge rates of the springs. The springs in the Beitou (BT), Xingyi Road (XYR), Zhongshanlou (ZSL), and Lengshuikeng (LSK) subzones are suitable for supplying tourism hotels with a sufficient quantity of spring water because they have high or moderate discharge rates. Furthermore, natural hot springs in riverbeds and valleys should be developed in the Dingbeitou (DBT), ZSL, Xiayoukeng (XYK), and Macao (MC) subzones because of low discharge rates and low or moderate water temperatures.

  3. Effect of a 5000 ppm fluoride toothpaste and a 250 ppm fluoride mouth rinse on the demineralisation of dentin surfaces.

    Science.gov (United States)

    Bizhang, Mozhgan; Chun, Yong-Hee P; Winterfeld, Mai-Trinh; Altenburger, Markus J; Raab, Wolfgang H M; Zimmer, Stefan

    2009-07-23

    The purpose of this study was to test the null hypothesis that there is no difference between the effect of (1) a 5000 ppm fluoride toothpaste, and (2) a 250 ppm fluoride mouth rinse on demineralized human dentin surfaces, against the alternative hypothesis of a difference. Dentin specimens were obtained from the cervical regions of 45 extracted human third molars. Half the surface of each specimen was sealed with a self-etching adhesive system and served as the reference surface. The dentin specimens were randomly assigned to one of the three groups, 5000 ppm fluoride toothpaste (Duraphat), 250 ppm fluoride mouth rinse (Meridol) and distilled water (negative control).An intraoral appliance was made for one volunteer. In each test cycle, 15 specimens were inserted in the appliance and worn for 24 hours a day, over a period of three weeks.Once daily, the appliance was immersed in the agent being tested; either toothpaste slurry, mouth rinse or distilled water for 60 seconds.Demineralization was assessed in terms of lesion depth (microm) and mineral loss (vol. % x microm) by transversal microradiography. Data analysis was accomplished using Kolmogorov-Smirnov test and ANOVA (SPSS 12.0).Statistically significant differences for mineral loss and lesion depth were found between the toothpaste and the mouth rinse as well as between the toothpaste and the control group, but not between the mouth rinse and the control group. Within the limitations of this study, the results suggest that treatment of demineralised dentin with a toothpaste containing 5000 ppm fluoride may considerably reduce mineral loss and lesion depth on exposed dentin.

  4. Removal of caffeine from water by combining dielectric barrier discharge (DBD plasma with goethite

    Directory of Open Access Journals (Sweden)

    Jian Wang

    2017-07-01

    Full Text Available In this research, dielectric barrier discharge plasma was developed to cooperate with goethite for removing caffeine in aqueous solution. Goethite was characterized by X-ray diffraction and scanning electron microscopy. The effects of input power, initial concentration and catalysts concentration on the removal efficiency of caffeine were evaluated. Furthermore, the degradation pathways of caffeine were also discussed preliminarily. In the case of caffeine concentration at 50 mg L−1, the degradation efficiency of caffeine was improved from 41% to 94% after 24 min on the conditions of input power of 75 W by combining goethite catalysts (2.5 g L−1, while the energy efficiency could be enhanced 1.6–2.3 times compared to the single DBD reactor. The reaction mechanism experiments demonstrated that attack by hydroxyl radical and ozone was the main degradation process of caffeine in aqueous solution. These studies also provided a theoretical and practical basis for the application of DBD-goethite in treatment of caffeine from water.

  5. Deuteration of metals through electric discharges

    International Nuclear Information System (INIS)

    Balderas G, L.M.

    1995-01-01

    In this work deuteration of titanium and a stainless steel through electrical discharges in a vacuum chamber was performed at different thermodynamic conditions. The samples were plates of 0.03 x 4.5 x 54 cm. The titanium sample was first cleaning with chloroform. The oxide layer was removed by cleaning the sample with a 1:1:1 mixture of water, nitric acid and sulphuric acid. Later was rinsed in water and dried with acetone. Finally, was treated with HCl to form an hydride layer on the surface. The stainless steel sample was only cleaned with soap and cleaning with acetone. The samples were cleaning at low pressure for several days with high temperature short cycles. The deuterium was loaded to the chamber at room temperature having absorption on the titanium samples at 10 3 at 10 1 mbar. Afterwards that the samples were heated up at 330 C and was observed the deuterium absorption in the same pressure range. Forced deuteration through electrical discharges between the sample and the chamber was tried obtaining absorption in the range of 10 3 at 10 2 mbar, however the deuterium absorption only was observed in specific cases. In order to detect neutron emission or released particles in this experiment were used alanine detectors and series of plastic CR-39 and borate films. No neutron were detected in the passive systems used in the experiments. (Author)

  6. Ecohydrological modelling of water discharge and nitrate loads in a mesoscale lowland catchment, Germany

    Directory of Open Access Journals (Sweden)

    N. Fohrer

    2009-08-01

    Full Text Available The aims of this study are to identify the capacities of applying an ecohydrological model for simulating flow and to assess the impact of point and non-point source pollution on nitrate loads in a complex lowland catchment, which has special hydrological characteristics in comparison with those of other catchments. The study area Kielstau catchment has a size of approximately 50 km2 and is located in the North German lowlands. The water quality is not only influenced by the predominating agricultural land use in the catchment as cropland and pasture, but also by six municipal wastewater treatment plants.

    Ecohydrological models like the SWAT model (Soil and Water Assessment Tool are useful tools for simulating nutrient loads in river catchments. Diffuse entries from the agriculture resulting from fertilizers as well as punctual entries from the wastewater treatment plants are implemented in the model set-up.

    The results of this study show good agreement between simulated and measured daily discharges with a Nash-Sutcliffe efficiency and a correlation coefficient of 0.76 and 0.88 for the calibration period (November 1998 to October 2004; 0.75 and 0.92 for the validation period (November 2004 to December 2007. The model efficiency for daily nitrate loads is 0.64 and 0.5 for the calibration period (June 2005 to May 2007 and the validation period (June 2007 to December 2007, respectively. The study revealed that SWAT performed satisfactorily in simulating daily flow and nitrate loads at the lowland catchment in Northern Germany.

  7. Plutonium isotopic composition of high burnup spent fuel discharged from light water reactors

    International Nuclear Information System (INIS)

    Nakano, Yoshihiro; Okubo, Tsutomu

    2011-01-01

    Highlights: → Pu isotopic composition of fuel affects FBR core nuclear characteristics very much. → Spent fuel compositions of next generation LWRs with burnup of 70 GWd/t were obtained. → Pu isotopic composition and amount in the spent fuel with 70 GWd/t were evaluated. → Spectral shift rods of high burnup BWR increases the fissile Pu fraction of spent fuel. → Wide fuel rod pitch of high burnup PWR lowers the fissile Pu fraction of spent fuel. - Abstract: The isotopic composition and amount of plutonium (Pu) in spent fuel from a high burnup boiling water reactor (HB-BWR) and a high burnup pressurized water reactor (HB-PWR), each with an average discharge burnup of 70 GWd/t, were estimated, in order to evaluate fast breeder reactor (FBR) fuel composition in the transition period from LWRs to FBRs. The HB-BWR employs spectral shift rods and the neutron spectrum is shifted through the operation cycle. The weight fraction of fissile plutonium (Puf) isotopes to the total plutonium in HB-BWR spent fuel after 5 years cooling is 62%, which is larger than that of conventional BWRs with average burnup of 45 GWd/t, because of the spectral shift operation. The amount of Pu produced in the HB-BWR is also larger than that produced in a conventional BWR. The HB-PWR uses a wider pitch 17 x 17 fuel rod assembly to optimize neutron slowing down. The Puf fraction of HB-PWR spent fuel after 5 years cooling is 56%, which is smaller than that of conventional PWRs with average burnup of 49 GWd/t, mainly because of the wider pitch. The amount of Pu produced in the HB-PWR is also smaller than that in conventional PWRs.

  8. Effects of pulse frequency of input power on the physical and chemical properties of pulsed streamer discharge plasmas in water

    Czech Academy of Sciences Publication Activity Database

    Ruma, Ruma.; Lukeš, Petr; Aoki, N.; Doležalová, Eva; Hosseini, S.H.R.; Sakugawa, T.; Akiyama, H.

    2013-01-01

    Roč. 46, č. 12 (2013), s. 125202-125202 ISSN 0022-3727 R&D Projects: GA ČR(CZ) GD104/09/H080 Grant - others:Rada Programu interní podpory projektů mezinárodní spolupráce AV ČR(CZ) M100431203 Program:M Institutional support: RVO:61389021 Keywords : discharge in water * pulsed power * pulse frequency * hydrogen peroxide * organic dye * bacteria * generator * liquids Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 2.521, year: 2013 http://dx.doi.org/10.1088/0022-3727/46/12/125202

  9. Occurrence and distribution of antibiotics in coastal water of the Bohai Bay, China: Impacts of river discharge and aquaculture activities

    International Nuclear Information System (INIS)

    Zou Shichun; Xu Weihai; Zhang Ruijie; Tang Jianhui; Chen Yingjun; Zhang Gan

    2011-01-01

    The presence of 21 antibiotics in six different groups was investigated in coastal water of the Bohai Bay. Meantime, to illuminate the potential effects caused by the river discharge and aquaculture activities, wastewater from three breeding plants and surface water from six rivers flowing into the Bohai Bay were also analyzed for the selected antibiotics. The result revealed that measured antibiotics in the North Bobai Bay were generally higher than those in the South, highlighting the remarkable effects of high density of human activities on the exposure of antibiotics in environment. The antibiotics found in the six rivers were generally higher than those in the Bohai Bay reflecting the important antibiotics source of river discharge. This study reveals that the high consumption of some antibiotics in aquaculture activities may pose high ecological risk to the bay. - Highlights: → Some antibiotics were ubiquitous with high concentration in the Bohai bay, North China. → The antibiotics were mainly from the six rivers discharge around the Bay. → Antibiotics are commonly used in aquaculture activities around the Bay. → Aquaculture was suggested to be an important antibiotics source in the Bay. - River discharge and aquaculture were suggested to be important sources for antibiotics occurred in the coastal water of the Bohai Bay, North China.

  10. Stratification of living organisms in ballast tanks: how do organism concentrations vary as ballast water is discharged?

    Science.gov (United States)

    First, Matthew R; Robbins-Wamsley, Stephanie H; Riley, Scott C; Moser, Cameron S; Smith, George E; Tamburri, Mario N; Drake, Lisa A

    2013-05-07

    Vertical migrations of living organisms and settling of particle-attached organisms lead to uneven distributions of biota at different depths in the water column. In ballast tanks, heterogeneity could lead to different population estimates depending on the portion of the discharge sampled. For example, concentrations of organisms exceeding a discharge standard may not be detected if sampling occurs during periods of the discharge when concentrations are low. To determine the degree of stratification, water from ballast tanks was sampled at two experimental facilities as the tanks were drained after water was held for 1 or 5 days. Living organisms ≥50 μm were counted in discrete segments of the drain (e.g., the first 20 min of the drain operation, the second 20 min interval, etc.), thus representing different strata in the tank. In 1 and 5 day trials at both facilities, concentrations of organisms varied among drain segments, and the patterns of stratification varied among replicate trials. From numerical simulations, the optimal sampling strategy for stratified tanks is to collect multiple time-integrated samples spaced relatively evenly throughout the discharge event.

  11. Impacts of a high-discharge submarine sewage outfall on water quality in the coastal zone of Salvador (Bahia, Brazil)

    International Nuclear Information System (INIS)

    Roth, F.; Lessa, G.C.; Wild, C.; Kikuchi, R.K.P.; Naumann, M.S.

    2016-01-01

    Carbon and nitrogen stable isotopic signatures of suspended particulate organic matter and seawater biological oxygen demand (BOD) were measured along a coastal transect during summer 2015 to investigate pollution impacts of a high-discharge submarine sewage outfall close to Salvador, Brazil. Impacts of untreated sewage discharge were evident at the outfall site by depleted δ 13 C org and δ 15 N signatures and 4-fold increased BOD rates. Pollution effects of a sewage plume were detectable for more than 6 km downstream from the outfall site, as seasonal wind- and tide-driven shelf hydrodynamics facilitated its advective transport into near-shore waters. There, sewage pollution was detectable at recreational beaches by depleted stable isotope signatures and elevated BOD rates at high tides, suggesting high bacterial activity and increased infection risk by human pathogens. These findings indicate the urgent necessity for appropriate wastewater treatment in Salvador to achieve acceptable standards for released effluents and coastal zone water quality. - Highlights: •Pollution by untreated sewage discharge is evident at the outfall and in Salvador's coastal zone. •Seasonal wind- and tide-driven surface currents control advective transport of discharged sewage. •Water quality at Salvador's recreational beaches is impacted by a plume of untreated sewage.

  12. Introduction to Superconducting RF Structures and the Effect of High Pressure Rinsing

    Energy Technology Data Exchange (ETDEWEB)

    Tajima, Tsuyoshi [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-06-30

    This presentation begins by describing RF superconductivity and SRF accelerating structures. Then the use of superconducting RF structures in a number of accelerators around the world is reviewed; for example, the International Linear Collider (ILC) will use ~16,000 SRF cavities with ~2,000 cryomodules to get 500 GeV e⁺/e⁻ colliding energy. Field emission control was (and still is) a very important practical issue for SRF cavity development. It has been found that high-pressure ultrapure water rinsing as a final cleaning step after chemical surface treatment resulted in consistent performance of single- and multicell superconducting cavities.

  13. Introduction to Superconducting RF Structures and the Effect of High Pressure Rinsing

    International Nuclear Information System (INIS)

    Tajima, Tsuyoshi

    2016-01-01

    This presentation begins by describing RF superconductivity and SRF accelerating structures. Then the use of superconducting RF structures in a number of accelerators around the world is reviewed; for example, the International Linear Collider (ILC) will use ~16,000 SRF cavities with ~2,000 cryomodules to get 500 GeV e@@@/e@@@ colliding energy. Field emission control was (and still is) a very important practical issue for SRF cavity development. It has been found that high-pressure ultrapure water rinsing as a final cleaning step after chemical surface treatment resulted in consistent performance of single- and multicell superconducting cavities.

  14. Microsecond Electrical Discharge in Water in Plate-to-Plate Configuration With Nitrogen Bubble Injection

    Czech Academy of Sciences Publication Activity Database

    Stelmashuk, Vitaliy

    2016-01-01

    Roč. 44, č. 4 (2016), s. 702-707 ISSN 0093-3813 Institutional support: RVO:61389021 Keywords : Electric breakdown * plate electrodes * underwater discharge Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 1.052, year: 2016 http://ieeexplore.ieee.org/xpl/tocresult.jsp?isnumber=7450213

  15. Nanosecond Discharge in Bubbled Liquid n-Heptane: Effects of Gas Composition and Water Addition

    KAUST Repository

    Hamdan, Ahmad; Cha, Min

    2016-01-01

    in liquid n-heptane with single and double gaseous bubbles in the gap between electrodes. We introduce discharge probability (DP) to characterize the stochastic nature of the discharges, and we investigate the dependence of DP on the gap distance, applied

  16. Forsmark site investigation. Monitoring of brook water levels, electrical conductivities, temperatures and discharges January-December 2010

    Energy Technology Data Exchange (ETDEWEB)

    Johansson, Per-Olof (Artesia Grundvattenkonsult (Sweden)); Juston, John (Juston Konsult (Sweden))

    2011-06-15

    This document reports the monitoring of water levels, electrical conductivities, temperatures and discharges at four brook discharge gauging stations, and the monitoring of water electrical conductivity at the outlet of Lake Bolundsfjaerden in the Forsmark area. The report presents data from 1 January through 31 December 2010 and is a continuation of reporting from Johansson and Juston (2007, 2009, 2011), which covered the periods from 1 April 2004 through 31 March 2007, 1 April 2007 through 31 December 2008, and 1 January through 31 December 2009, respectively. Long-throated flumes equipped with automatically recording devices were used for the discharge measurements. Every c. 14 days the water depths at the upstream edge of the flumes were measured manually by a ruler as a check. Electrical conductivity and temperature were automatically recorded and these parameters were also measured manually every c. 14 days with the site investigation field devices. SKB's Hydro Monitoring System (HMS) was used to collect and store all data. From HMS quality assured data were transferred to SKB's primary database Sicada. Measurements of levels, electrical conductivities and temperatures were made every 10 minutes (every 30 minutes for electrical conductivity at the outlet of Lake Bolundsfjaerden). For the calculation of discharge, quality assured water level data from the flumes were used. The calculation procedure included consolidation of the time series to hourly averages, screening of data for removal of short-term spikes, noise and other data that were judged erroneous. After the calculations were performed, the results were delivered to Sicada. The amplitudes of water level variations during this reporting period were 0.41-0.55 m and the mean electrical conductivities varied between 23 and 39 mS/m at the four discharge stations. However, due to mal-function of measuring devices for electrical conductivity, data were missing for relatively long time periods. Due

  17. Influence of cooling water discharges from Kaiga Nuclear Power Plant on aquatic ecology of the Kadra reservoir

    International Nuclear Information System (INIS)

    Ghosh, T.K.; Zargar, S.; Kulkarni, A.V.

    2007-01-01

    The alterations induced in the ambient temperature can lead to wide manifestations in species distribution and community structure. In general, elevated water temperature causes changes in species composition, species dominance, standing crop and productivity of biota including phytoplankton communities in any aquatic ecosystem. Thus warm water discharges from power plants into the receiving water bodies may adversely affect aquatic ecology. In the absence of exhaustive data on the response of aquatic organisms and ecosystems in the tropics to elevated temperatures, the only option is to draw inferences, from the experiences in the subtropical and temperature areas. Since, sufficient data on similar line are not available in tropical environment, present paper delineates certain aspects of aquatic ecology of the Kadra reservoir where cooling water is discharged. The study suggests the heated effluents from Kaiga Nuclear Power plant caused changes in dissolved oxygen and pH of water, heterotrophic bacterial population, sediment biogeochemical cycles related biochemical processes, species composition, species dominance, standing crop and productivity of biota including phytoplankton communities within 500 m from End of Discharge Canal point of Kadra reservoir when two units are running in full capacity. (author)

  18. Submarine groundwater discharge into the coast revealed by water chemistry of man-made undersea liquefied petroleum gas cavern

    Science.gov (United States)

    Lee, Jin-Yong; Cho, Byung Wook

    2008-10-01

    SummaryThe occurrence of submarine groundwater discharge (SGD) as well as its supply of many nutrients and metals to coastal seawaters is now generally known. However, previous studies have focused on the chemical and radiological analysis of groundwater, surface seawater, shallow marine sediments and their pore waters, as well as the measurement of upward flow through the marine sediments, as end members of the discharge process. In this study, chemical and isotopic analysis results of marine subsurface waters are reported. These were obtained from deep boreholes of an undersea liquefied petroleum gas (LPG) storage cavern, located about 8 km off the western coast of Korea. The cavern is about 130-150 m below the sea bottom, which is covered by a 4.8-19.5 m silty clay stratum. An isotopic composition (δ 2H and δ 18O) of the marine subsurface waters falls on a mixing line between terrestrial groundwater and seawater. Vertical EC profiling at the cavern boreholes revealed the existence of a fresh water zone. An increase in the contents of ferrous iron and manganese and a decrease in levels of nitrate, bicarbonate and cavern seepage were recorded in August 2006, indicating a decreased submarine groundwater flux originating from land, mainly caused by an elevated cavern gas pressure. It is suggested in this study that the main source of fresh waters in the man-made undersea cavern is the submarine groundwater discharge mainly originating from the land.

  19. Kinetics and dynamics of nanosecond streamer discharge in atmospheric-pressure gas bubble suspended in distilled water under saturated vapor pressure conditions

    KAUST Repository

    Sharma, Ashish; Levko, Dmitry; Raja, Laxminarayan L; Cha, Min

    2016-01-01

    We perform computational studies of nanosecond streamer discharges generated in helium bubbles immersed in distilled water under atmospheric pressure conditions. The model takes into account the presence of water vapor in the gas bubble

  20. Effects of River Discharge and Land Use and Land Cover (LULC) on Water Quality Dynamics in Migina Catchment, Rwanda

    Science.gov (United States)

    Uwimana, Abias; van Dam, Anne; Gettel, Gretchen; Bigirimana, Bonfils; Irvine, Kenneth

    2017-09-01

    Agricultural intensification may accelerate the loss of wetlands, increasing the concentrations of nutrients and sediments in downstream water bodies. The objective of this study was to assess the effects of land use and land cover and river discharge on water quality in the Migina catchment, southern Rwanda. Rainfall, discharge and water quality (total nitrogen, total phosphorus, total suspended solids, dissolved oxygen, conductivity, pH, and temperature) were measured in different periods from May 2009 to June 2013. In 2011, measurements were done at the outlets of 3 sub-catchments (Munyazi, Mukura and Akagera). Between May 2012 and May 2013 the measurements were done in 16 reaches of Munyazi dominated by rice, vegetables, grass/forest or ponds/reservoirs. Water quality was also measured during two rainfall events. Results showed seasonal trends in water quality associated with high water flows and farming activities. Across all sites, the total suspended solids related positively to discharge, increasing 2-8 times during high flow periods. Conductivity, temperature, dissolved oxygen, and pH decreased with increasing discharge, while total nitrogen and total phosphorus did not show a clear pattern. The total suspended solids concentrations were consistently higher downstream of reaches dominated by rice and vegetable farming. For total nitrogen and total phosphorus results were mixed, but suggesting higher concentration of total nitrogen and total phosphorus during the dry and early rainy (and farming) season, and then wash out during the rainy season, with subsequent dilution at the end of the rains. Rice and vegetable farming generate the transport of sediment as opposed to ponds/reservoir and grass/forest.

  1. A caffeine-maltodextrin mouth rinse counters mental fatigue.

    Science.gov (United States)

    Van Cutsem, Jeroen; De Pauw, Kevin; Marcora, Samuele; Meeusen, Romain; Roelands, Bart

    2018-04-01

    Mental fatigue is a psychobiological state caused by prolonged periods of demanding cognitive activity that has negative implications on many aspects in daily life. Caffeine and carbohydrate ingestion have been shown to be able to reduce these negative effects of mental fatigue. Intake of these substances might however be less desirable in some situations (e.g., restricted caloric intake, Ramadan). Rinsing caffeine or glucose within the mouth has already been shown to improve exercise performance. Therefore, we sought to evaluate the effect of frequent caffeine-maltodextrin (CAF-MALT) mouth rinsing on mental fatigue induced by a prolonged cognitive task. Ten males (age 23 ± 2 years, physical activity 7.3 ± 4.3 h/week, low CAF users) performed two trials. Participants first completed a Flanker task (3 min), then performed a 90-min mentally fatiguing task (Stroop task), followed by another Flanker task. Before the start and after each 12.5% of the Stroop task (eight blocks), subjects received a CAF-MALT mouth rinse (MR: 0.3 g/25 ml CAF: 1.6g/25 ml MALT) or placebo (PLAC: 25 ml artificial saliva). Self-reported mental fatigue was lower in MR (p = 0.017) compared to PLAC. Normalized accuracy (accuracy first block = 100%) was higher in the last block of the Stroop in MR (p = 0.032) compared to PLAC. P2 amplitude in the dorsolateral prefrontal cortex (DLPFC) decreased over time only in PLAC (p = 0.017). Frequent mouth rinsing during a prolonged and demanding cognitive task reduces mental fatigue compared to mouth rinsing with artificial saliva.

  2. Amendment of the administrative skeleton provision for minimum requirements to be met by waste water discharged into bodies of water. Administrative skeleton provision on waste water of 25 November, 1992

    International Nuclear Information System (INIS)

    1994-01-01

    This provision applies to waste water to be discharged into bodies of water and whose pollution load stems mainly from the sectors indicated in appendices. Without prejudice to stricter requirements governing the execution of the Water Resources Act, the requirements to be met by the discharge of waste water, as indicated in appendices, are defined in accordance with section 7a, subsection 1, number 3 of the Water Resources Act. - The maximum concentrations indicated in appendices, for instance for waste water from brown coal briquetting plant, black coal treatment plant, petroleum refineries and flue gas scrubbers at combustion plant, relate to waste water in the discharge pipe of the waste water treatment plant. Contrary to technical rules that may apply in each instance, these concentrations must not be attained by dilution or mixing. (orig.) [de

  3. 21 CFR 872.5580 - Oral rinse to reduce the adhesion of dental plaque.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Oral rinse to reduce the adhesion of dental plaque... SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Therapeutic Devices § 872.5580 Oral rinse to reduce the adhesion of dental plaque. (a) Identification. The device is assigned the generic name oral rinse to reduce...

  4. Wet-weather urban discharges: implications from adopting the revised European Directive concerning the quality of bathing water.

    Science.gov (United States)

    David, L M; Matos, J S

    2005-01-01

    Wet weather urban discharges are responsible for bathing water contamination. The proposal for a revised EU Directive concerning the quality of bathing water imposes significantly more stringent requirements for the management of bathing water quality, with particularly important repercussions on beaches subjected to short-term pollution incidents. The paper reviews the aspects from EU legislation most directly related to the problem of wet-weather discharges, placing special emphasis on the recent revision process of the Directive on bathing water quality, and evaluates the benefits of some potential solutions based on continuous modelling of a combined sewer system. Increasing the sewer system storage capacity or the STP hydraulic capacity may substantially reduce the untreated discharge volumes, but spill frequency reductions under 2 to 3 spill days per bathing season will hardly be achieved. Results show the severe strains that local rainfall patterns would place on compliance with the Commission's proposal for a revised Directive and highlight the importance of the changes introduced in the amended proposal recently approved by the Council, making it less prescriptive if adequate measures are adopted to prevent bathers' exposure to short-term pollution incidents.

  5. Effect of water flux and sediment discharge of the Yangtze River on PAHs sedimentation in the estuary.

    Science.gov (United States)

    Li, Rufeng; Feng, Chenghong; Wang, Dongxin; He, Maozhi; Hu, Lijuan; Shen, Zhenyao

    2016-12-01

    Historical distribution characteristics of polycyclic aromatic hydrocarbons (PAHs) and their carriers (i.e., organic matter and mineral particles) in the sediment cores of the Yangtze Estuary were investigated, with emphasis laid on the role of the Yangtze River. Grain size component of sediments (clay, silt, and sand) and organic carbon (black carbon and total organic carbon) in the sediment cores were markedly affected by water flux and sediment discharge of the Yangtze River. Qualitative and quantitative analysis results showed that sands and black carbon acted as the main carriers of PAHs. The sedimentation of two-ring to three-ring PAHs in the estuary had significant correlations with water flux and sediment discharge of the Yangtze River. The relative lower level of the four-ring and five-ring to six-ring PAHs concentrations appeared around the year 2003 and remained for the following several years. This time period accorded well with the water impoundment time of the Three Gorges Reservoir. The decreased level of two-ring to three-ring PAHs occurred in the year 1994, and the peak points around the year 2009 indicated that PAHs sedimentation in the estuary also had close relationship to severe drought and flood in the catchments. The findings presented in this paper could provide references for assessing the impacts of water flux and sediment discharge on the historical deposition of PAHs and their carriers in the Yangtze Estuary.

  6. Sea Water Acidification Affects Osmotic Swelling, Regulatory Volume Decrease and Discharge in Nematocytes of the Jellyfish Pelagia noctiluca

    Directory of Open Access Journals (Sweden)

    Rossana Morabito

    2013-12-01

    Full Text Available Background: Increased acidification/PCO2 of sea water is a threat to the environment and affects the homeostasis of marine animals. In this study, the effect of sea water pH changes on the osmotic phase (OP, regulatory volume decrease (RVD and discharge of the jellyfish Pelagia noctiluca (Cnidaria, Scyphozoa nematocytes, collected from the Strait of Messina (Italy, was assessed. Methods: Isolated nematocytes, suspended in artificial sea water (ASW with pH 7.65, 6.5 and 4.5, were exposed to hyposmotic ASW of the same pH values and their osmotic response and RVD measured optically in a special flow through chamber. Nematocyte discharge was analyzed in situ in ASW at all three pH values. Results: At normal pH (7.65, nematocytes subjected to hyposmotic shock first expanded osmotically and then regulated their cell volume within 15 min. Exposure to hyposmotic ASW pH 6.5 and 4.5 compromised the OP and reduced or totally abrogated the ensuing RVD, respectively. Acidic pH also significantly reduced the nematocyte discharge response. Conclusion: Data indicate that the homeostasis and function of Cnidarians may be altered by environmental changes such as sea water acidification, thereby validating their use as novel bioindicators for the quality of the marine environment.

  7. Sea water acidification affects osmotic swelling, regulatory volume decrease and discharge in nematocytes of the jellyfish Pelagia noctiluca.

    Science.gov (United States)

    Morabito, Rossana; Marino, Angela; Lauf, Peter K; Adragna, Norma C; La Spada, Giuseppa

    2013-01-01

    Increased acidification/PCO2 of sea water is a threat to the environment and affects the homeostasis of marine animals. In this study, the effect of sea water pH changes on the osmotic phase (OP), regulatory volume decrease (RVD) and discharge of the jellyfish Pelagia noctiluca (Cnidaria, Scyphozoa) nematocytes, collected from the Strait of Messina (Italy), was assessed. Isolated nematocytes, suspended in artificial sea water (ASW) with pH 7.65, 6.5 and 4.5, were exposed to hyposmotic ASW of the same pH values and their osmotic response and RVD measured optically in a special flow through chamber. Nematocyte discharge was analyzed in situ in ASW at all three pH values. At normal pH (7.65), nematocytes subjected to hyposmotic shock first expanded osmotically and then regulated their cell volume within 15 min. Exposure to hyposmotic ASW pH 6.5 and 4.5 compromised the OP and reduced or totally abrogated the ensuing RVD, respectively. Acidic pH also significantly reduced the nematocyte discharge response. Data indicate that the homeostasis and function of Cnidarians may be altered by environmental changes such as sea water acidification, thereby validating their use as novel bioindicators for the quality of the marine environment. © 2014 S. Karger AG, Basel.

  8. Assessment of water exchange between a discharge region and the open sea A comparison of different methodological concepts

    Science.gov (United States)

    Döös, Kristofer; Engqvist, Anders

    2007-09-01

    Two different methods of estimating the water exchange through the Baltic coastal region of Laxemar have been used, consisting of particle trajectories and passive tracers. Water is traced from and to a small discharge region near the coast. The discharge material in this region is treated as zero-dimensional particles or tracers with neutral buoyancy. The real discharge material could be a leakage of radio-nuclides through the sea floor from an underground repository of nuclear waste. Water exchange rates between the discharge region and the model domain are estimated using both forward and backward trajectories as well as passive tracers. The Lagrangian trajectories can account for the time evolution of the water exchange while the tracers give one average age per model grid box. Water exchange times such as residence time, age and transient times have been calculated with trajectories but only the average age (AvA) for tracers. The trajectory calculations provide a more detailed time evolution than the tracers. On the other hand the tracers are integrated "on-line" simultaneously in the sea circulation model with the same time step while the Lagrangian trajectories are integrated "off-line" from the stored model velocities with its inherent temporal resolution, presently 1 h. The sub-grid turbulence is parameterised as the Laplacian diffusion for the passive tracers and with an extra stochastic velocity for trajectories. The importance of the parameterised sub-grid turbulence for the trajectories is estimated to give an extra diffusion of the same order as the Laplacian diffusion by comparing the Lagrangian dispersions with and without parameterisation. The results of the different methods are similar but depend on the chosen diffusivity coefficient with a slightly higher correlation between trajectories and tracers when integrated with a lower diffusivity coefficient.

  9. Weekly variations of discharge and groundwater quality caused by intermittent water supply in an urbanized karst catchment

    Science.gov (United States)

    Grimmeisen, Felix; Zemann, Moritz; Goeppert, Nadine; Goldscheider, Nico

    2016-06-01

    Leaky sewerage and water distribution networks are an enormous problem throughout the world, specifically in developing countries and regions with water scarcity. Especially in many arid and semi-arid regions, intermittent water supply (IWS) is common practice to cope with water shortage. This study investigates the combined influence of urban activities, IWS and water losses on groundwater quality and discusses the implications for water management. In the city of As-Salt (Jordan), local water supply is mostly based on groundwater from the karst aquifer that underlies the city. Water is delivered to different supply zones for 24, 48 or 60 h each week with drinking water losses of around 50-60%. Fecal contamination in groundwater, mostly originating from the likewise leaky sewer system is a severe challenge for the local water supplier. In order to improve understanding of the local water cycle and contamination dynamics in the aquifer beneath the city, a down gradient spring and an observation well were chosen to identify contaminant occurrence and loads. Nitrate, Escherichia coli, spring discharge and the well water level were monitored for 2 years. Autocorrelation analyses of time series recorded during the dry season revealed weekly periodicity of spring discharge (45 ± 3.9 L s-1) and NO3-N concentrations (11.4 ± 0.8 mg L-1) along with weekly varying E. coli levels partly exceeding 2.420 MPN 100 mL-1. Cross-correlation analyses demonstrate a significant and inverse correlation of nitrate and discharge variations which points to a periodic dilution of contaminated groundwater by freshwater from the leaking IWS being the principal cause of the observed fluctuations. Contaminant inputs from leaking sewers appear to be rather constant. The results reveal the distinct impact of leaking clean IWS on the local groundwater and subsequently on the local water supply and therefore demonstrate the need for action regarding the mitigation of groundwater contamination and

  10. Decolorization of reactive textile dyes using water falling film dielectric barrier discharge

    Energy Technology Data Exchange (ETDEWEB)

    Dojcinovic, Biljana P. [Institute of Chemistry, Technology and Metallurgy, Center of Chemistry, Studentski trg 12-16, 11000 Belgrade (Serbia); Roglic, Goran M. [Faculty of Chemistry, University of Belgrade, P.O. Box 158, 11000 Belgrade (Serbia); Obradovic, Bratislav M., E-mail: obrat@ff.bg.ac.rs [Faculty of Physics, University of Belgrade, P.O. Box 368, 11000 Belgrade (Serbia); Kuraica, Milorad M. [Faculty of Physics, University of Belgrade, P.O. Box 368, 11000 Belgrade (Serbia); Kostic, Mirjana M. [Faculty of Technology and Metallurgy, Department of Textile Engineering, Karnegijeva 4, 11000 Belgrade (Serbia); Nesic, Jelena; Manojlovic, Dragan D. [Faculty of Chemistry, University of Belgrade, P.O. Box 158, 11000 Belgrade (Serbia)

    2011-08-30

    Highlights: {yields} Decolorization of four reactive textile dyes using non-thermal plasma reactor. {yields} Influence of applied energy on decolorization. {yields} Effects of initial pH and addition of homogeneous catalysts. {yields} Toxicity evaluation using the brine shrimp as a test organism. - Abstract: Decolorization of reactive textile dyes Reactive Black 5, Reactive Blue 52, Reactive Yellow 125 and Reactive Green 15 was studied using advanced oxidation processes (AOPs) in a non-thermal plasma reactor, based on coaxial water falling film dielectric barrier discharge (DBD). Used initial dye concentrations in the solution were 40.0 and 80.0 mg/L. The effects of different initial pH of dye solutions, and addition of homogeneous catalysts (H{sub 2}O{sub 2}, Fe{sup 2+} and Cu{sup 2+}) on the decolorization during subsequent recirculation of dye solution through the DBD reactor, i.e. applied energy density (45-315 kJ/L) were studied. Influence of residence time was investigated over a period of 24 h. Change of pH values and effect of pH adjustments of dye solution after each recirculation on the decolorization was also tested. It was found that the initial pH of dye solutions and pH adjustments of dye solution after each recirculation did not influence the decolorization. The most effective decolorization of 97% was obtained with addition of 10 mM H{sub 2}O{sub 2} in a system of 80.0 mg/L Reactive Black 5 with applied energy density of 45 kJ/L, after residence time of 24 h from plasma treatment. Toxicity was evaluated using the brine shrimp Artemia salina as a test organism.

  11. Decolorization of reactive textile dyes using water falling film dielectric barrier discharge

    International Nuclear Information System (INIS)

    Dojcinovic, Biljana P.; Roglic, Goran M.; Obradovic, Bratislav M.; Kuraica, Milorad M.; Kostic, Mirjana M.; Nesic, Jelena; Manojlovic, Dragan D.

    2011-01-01

    Highlights: → Decolorization of four reactive textile dyes using non-thermal plasma reactor. → Influence of applied energy on decolorization. → Effects of initial pH and addition of homogeneous catalysts. → Toxicity evaluation using the brine shrimp as a test organism. - Abstract: Decolorization of reactive textile dyes Reactive Black 5, Reactive Blue 52, Reactive Yellow 125 and Reactive Green 15 was studied using advanced oxidation processes (AOPs) in a non-thermal plasma reactor, based on coaxial water falling film dielectric barrier discharge (DBD). Used initial dye concentrations in the solution were 40.0 and 80.0 mg/L. The effects of different initial pH of dye solutions, and addition of homogeneous catalysts (H 2 O 2 , Fe 2+ and Cu 2+ ) on the decolorization during subsequent recirculation of dye solution through the DBD reactor, i.e. applied energy density (45-315 kJ/L) were studied. Influence of residence time was investigated over a period of 24 h. Change of pH values and effect of pH adjustments of dye solution after each recirculation on the decolorization was also tested. It was found that the initial pH of dye solutions and pH adjustments of dye solution after each recirculation did not influence the decolorization. The most effective decolorization of 97% was obtained with addition of 10 mM H 2 O 2 in a system of 80.0 mg/L Reactive Black 5 with applied energy density of 45 kJ/L, after residence time of 24 h from plasma treatment. Toxicity was evaluated using the brine shrimp Artemia salina as a test organism.

  12. Water uptake by two river red gum ( Eucalyptus camaldulensis) clones in a discharge site plantation in the Western Australian wheatbelt

    Science.gov (United States)

    Marshall, John K.; Morgan, Anne L.; Akilan, Kandia; Farrell, Richard C. C.; Bell, David T.

    1997-12-01

    The heat-pulse technique was used to estimate year-long water uptake in a discharge zone plantation of 9-year-old clonal Eucalyptus camaldulensis Dehnh. near Wubin, Western Australia. Water uptake matched rainfall closely during weter months but exceeded rainfall as the dry season progressed. Average annual water uptake (1148 mm) exceeded rainfall (432 mm) by about 2.7 fold and approached 56% of pan evaporation for the area. The data suggest that at least 37% (i.e. ( {1}/{2.7}) × 100 ) of the lower catchment discharge zone should be planted to prevent the rise of groundwater. Water uptake varied with soil environment, season and genotype. Upslope trees used more water than did downslope trees. Water uptake was higher in E. camaldulensis clone M80 than in clone M66 until late spring. The difference reversed as summer progressed. Both clones, however, have the potential to dry out the landscape when potential evapotranspiration exceeds rainfall. This variation in water uptake within the species indicates the potential for manipulating plantation uptake by matching tree characteristics to site characteristics. Controlled experiments on the heat-pulse technique indicated accuracy errors of approximately 10%. This, combined with the ability to obtain long-term, continuous data and the superior logistics of use of the heat-pulse technique, suggests that results obtained by it would be much more reliable than those achieved by the ventilated chamber technique.

  13. Removal of priority pollutants from water by means of dielectric barrier discharge atmospheric plasma

    Energy Technology Data Exchange (ETDEWEB)

    Hijosa-Valsero, María, E-mail: mhijv@unileon.es [Instituto de Diagnóstico Ambiental y Estudios del Agua (IDAEA), CID, CSIC, C/Jordi Girona 18-26, E-08034 Barcelona (Spain); Molina, Ricardo, E-mail: ricardo.molina@cid.csic.es [Instituto de Química Avanzada de Cataluña (IQAC), CID, CSIC, C/Jordi Girona 18-26, E-08034 Barcelona (Spain); Schikora, Hendrik, E-mail: hendrik.schikora@igb.fraunhofer.de [Fraunhofer IGB, Nobelstraße 12, 70569 Stuttgart (Germany); Müller, Michael, E-mail: michael.mueller@igb.fraunhofer.de [Fraunhofer IGB, Nobelstraße 12, 70569 Stuttgart (Germany); Bayona, Josep M., E-mail: josep.bayona@cid.csic.es [Instituto de Diagnóstico Ambiental y Estudios del Agua (IDAEA), CID, CSIC, C/Jordi Girona 18-26, E-08034 Barcelona (Spain)

    2013-11-15

    Highlights: • DBD plasma reactors were used to remove pollutants from aqueous solutions. • Atrazine, chlorfenvinfos, 2,4-dibromophenol and lindane were studied. • First-order degradation kinetics were observed for all the compounds. • Degradation by-products were identified by GC–MS. • Treatment efficiencies were lower in industrial wastewater than in pure water. -- Abstract: Two different nonthermal plasma reactors at atmospheric pressure were assessed for the removal of organic micropollutants (atrazine, chlorfenvinfos, 2,4-dibromophenol, and lindane) from aqueous solutions (1–5 mg L{sup −1}) at laboratory scale. Both devices were dielectric barrier discharge (DBD) reactors; one was a conventional batch reactor (R1) and the other a coaxial thin-falling-water-film reactor (R2). A first-order degradation kinetics was proposed for both experiments. The kinetic constants (k) were slightly faster in R1 (0.534 min{sup −1} for atrazine; 0.567 min{sup −1} for chlorfenvinfos; 0.802 min{sup −1} for 2,4-dibromophenol; 0.389 min{sup −1} for lindane) than in R2 (0.104 min{sup −1} for atrazine; 0.523 min{sup −1} for chlorfenvinfos; 0.273 min{sup −1} for 2,4-dibromophenol; 0.294 min{sup −1} for lindane). However, energy efficiencies were about one order of magnitude higher in R2 (89 mg kW{sup −1} h{sup −1} for atrazine; 447 mg kW{sup −1} h{sup −1} for chlorfenvinfos; 47 mg kW{sup −1} h{sup −1} for 2,4-dibromophenol; 50 mg kW{sup −1} h{sup −1} for lindane) than in R1. Degradation by-products of all four compounds were identified in R1. As expected, when the plasma treatment (R1) was applied to industrial wastewater spiked with atrazine or lindane, micropollutant removal was also achieved, although at a lower rate than with aqueous solutions (k = 0.117 min{sup −1} for atrazine; k = 0.061 min{sup −1} for lindane)

  14. Treatment of Dyeing Wastewater by Using Positive Pulsed Corona Discharge to Water Surface

    Science.gov (United States)

    Young, Sun Mok; Hyun, Tae Ahn; Joeng, Tai Kim

    2007-02-01

    This study investigated the treatment of textile-dyeing wastewater by using an electrical discharge technique (positive pulsed corona discharge). The high-voltage electrode was placed above the surface of the wastewater while the ground electrode was submerged in the wastewater. The electrical discharge starting at the tip of the high voltage electrode propagated toward the surface of the wastewater, producing various oxidative radicals and ozone. Oxygen was used as the working gas instead of air to prevent nitrogen oxides from forming. The simulated wastewater was made up with amaranth, which is a kind of azo dye. The results obtained showed that the chromaticity of the wastewater was almost completely removed within an hour. The ultraviolet/visible spectra of the wastewater treated by the electrical discharge revealed that the total hydrocarbon level also decreased significantly.

  15. Treatment of Dyeing Wastewater by Using Positive Pulsed Corona Discharge to Water Surface

    International Nuclear Information System (INIS)

    Mok, Young Sun; Ahn, Hyun Tae; Kim, Joeng Tai

    2007-01-01

    This study investigated the treatment of textile-dyeing wastewater by using an electrical discharge technique (positive pulsed corona discharge). The high-voltage electrode was placed above the surface of the wastewater while the ground electrode was submerged in the wastewater. The electrical discharge starting at the tip of the high voltage electrode propagated toward the surface of the wastewater, producing various oxidative radicals and ozone. Oxygen was used as the working gas instead of air to prevent nitrogen oxides from forming. The simulated wastewater was made up with amaranth, which is a kind of azo dye. The results obtained showed that the chromaticity of the wastewater was almost completely removed within an hour. The ultraviolet/visible spectra of the wastewater treated by the electrical discharge revealed that the total hydrocarbon level also decreased significantly

  16. The effect of daily fluoride mouth rinsing on enamel erosive/abrasive wear in situ.

    Science.gov (United States)

    Stenhagen, K R; Hove, L H; Holme, B; Tveit, A B

    2013-01-01

    It is not known whether application of fluoride agents on enamel results in lasting resistance to erosive/abrasive wear. We investigated if one daily mouth rinse with sodium fluoride (NaF), stannous fluoride (SnF(2)) or titanium tetrafluoride (TiF(4)) solutions protected enamel against erosive/abrasive wear in situ (a paired, randomised and blind study). Sixteen molars were cut into 4 specimens, each with one amalgam filling (measurement reference surface). Two teeth (2 × 4 specimens) were mounted bilaterally (buccal aspects) on acrylic mandibular appliances and worn for 9 days by 8 volunteers. Every morning, the specimens were brushed manually with water (30 s) extra-orally. Then fluoride solutions (0.4% SnF(2) pH 2.5; 0.15% TiF(4) pH 2.1; 0.2% NaF pH 6.5, all 0.05 M F) were applied (2 min). Three of the specimens from each tooth got different treatment, and the fourth served as control. At midday, the specimens were etched for 2 min in 300 ml fresh 0.01 M hydrochloric acid and rinsed in tap water. This etch procedure was repeated in the afternoon. Topographic measurements were performed by a white-light interferometer. Mean surface loss (±SD) for 16 teeth after 9 days was: SnF(2) 1.8 ± 1.9 µm, TiF(4) 3.1 ± 4.8 µm, NaF 26.3 ± 4.7 µm, control 32.3 ± 4.4 µm. Daily rinse with SnF(2), TiF(4) and NaF resulted in 94, 90 and 18% reduction in enamel erosive/abrasive wear, respectively, compared with control (p < 0.05). The superior protective effect of daily rinse with either stannous or titanium tetrafluoride solutions on erosive/abrasive enamel wear is promising. Copyright © 2012 S. Karger AG, Basel.

  17. Cross-linked cyclodextrin-based material for treatment of metals and organic substances present in industrial discharge waters

    Directory of Open Access Journals (Sweden)

    Élise Euvrard

    2016-08-01

    Full Text Available In this study, a polymer, prepared by crosslinking cyclodextrin (CD by means of a polycarboxylic acid, was used for the removal of pollutants from spiked solutions and discharge waters from the surface treatment industry. In spiked solutions containing five metals, sixteen polycyclic aromatic hydrocarbons (PAH and three alkylphenols (AP, the material exhibited high adsorption capacities: >99% of Co2+, Ni2+ and Zn2+ were removed, between 65 and 82% of the PAHs, as well as 69 to 90% of the APs. Due to the structure of the polymer and its specific characteristics, such as the presence of carboxylic groups and CD cavities, the adsorption mechanism involves four main interactions: ion exchange, electrostatic interactions and precipitation for metal removal, and inclusion complexes for organics removal. In industrial discharge waters, competition effects appeared, especially because of the presence of calcium at high concentrations, which competed with other pollutants for the adsorption sites of the adsorbent.

  18. Impacts of a high-discharge submarine sewage outfall on water quality in the coastal zone of Salvador (Bahia, Brazil)

    KAUST Repository

    Roth, Florian; Lessa, G.C.; Wild, C.; Kikuchi, R.K.P.; Naumann, M.S.

    2016-01-01

    Carbon and nitrogen stable isotopic signatures of suspended particulate organic matter and seawater biological oxygen demand (BOD) were measured along a coastal transect during summer 2015 to investigate pollution impacts of a high-discharge submarine sewage outfall close to Salvador, Brazil. Impacts of untreated sewage discharge were evident at the outfall site by depleted δ13Corg and δ15N signatures and 4-fold increased BOD rates. Pollution effects of a sewage plume were detectable for more than 6 km downstream from the outfall site, as seasonal wind- and tide-driven shelf hydrodynamics facilitated its advective transport into near-shore waters. There, sewage pollution was detectable at recreational beaches by depleted stable isotope signatures and elevated BOD rates at high tides, suggesting high bacterial activity and increased infection risk by human pathogens. These findings indicate the urgent necessity for appropriate wastewater treatment in Salvador to achieve acceptable standards for released effluents and coastal zone water quality.

  19. Occurrence and distribution of antibiotics in coastal water of the Bohai Bay, China: impacts of river discharge and aquaculture activities.

    Science.gov (United States)

    Zou, Shichun; Xu, Weihai; Zhang, Ruijie; Tang, Jianhui; Chen, Yingjun; Zhang, Gan

    2011-10-01

    The presence of 21 antibiotics in six different groups was investigated in coastal water of the Bohai Bay. Meantime, to illuminate the potential effects caused by the river discharge and aquaculture activities, wastewater from three breeding plants and surface water from six rivers flowing into the Bohai Bay were also analyzed for the selected antibiotics. The result revealed that measured antibiotics in the North Bobai Bay were generally higher than those in the South, highlighting the remarkable effects of high density of human activities on the exposure of antibiotics in environment. The antibiotics found in the six rivers were generally higher than those in the Bohai Bay reflecting the important antibiotics source of river discharge. This study reveals that the high consumption of some antibiotics in aquaculture activities may pose high ecological risk to the bay. Copyright © 2011 Elsevier Ltd. All rights reserved.

  20. Validation of the kinetic model for predicting the composition of chlorinated water discharged from power plant cooling systems

    International Nuclear Information System (INIS)

    Lietzke, M.H.

    1977-01-01

    The purpose of this report is to present a validation of a previously described kinetic model which was developed to predict the composition of chlorinated fresh water discharged from power plant cooling systems. The model was programmed in two versions: as a stand-alone program and as a part of a unified transport model developed from consistent mathematical models to simulate the dispersion of heated water and radioisotopic and chemical effluents from power plant discharges. The results of testing the model using analytical data taken during operation of the once-through cooling system of the Quad Cities Nuclear Station are described. Calculations are also presented on the Three Mile Island Nuclear Station which uses cooling towers

  1. Impacts of a high-discharge submarine sewage outfall on water quality in the coastal zone of Salvador (Bahia, Brazil)

    KAUST Repository

    Roth, Florian

    2016-03-30

    Carbon and nitrogen stable isotopic signatures of suspended particulate organic matter and seawater biological oxygen demand (BOD) were measured along a coastal transect during summer 2015 to investigate pollution impacts of a high-discharge submarine sewage outfall close to Salvador, Brazil. Impacts of untreated sewage discharge were evident at the outfall site by depleted δ13Corg and δ15N signatures and 4-fold increased BOD rates. Pollution effects of a sewage plume were detectable for more than 6 km downstream from the outfall site, as seasonal wind- and tide-driven shelf hydrodynamics facilitated its advective transport into near-shore waters. There, sewage pollution was detectable at recreational beaches by depleted stable isotope signatures and elevated BOD rates at high tides, suggesting high bacterial activity and increased infection risk by human pathogens. These findings indicate the urgent necessity for appropriate wastewater treatment in Salvador to achieve acceptable standards for released effluents and coastal zone water quality.

  2. Spatial-temporal evolution of self-organized loop-patterns on a water surface and a diffuse discharge in the gap

    Science.gov (United States)

    Li, Xuechen; Geng, Jinling; Jia, Pengying; Zhang, Panpan; Zhang, Qi; Li, Yaru

    2017-11-01

    Excited by an alternating current voltage, a patterned discharge and a diffuse discharge are generated in a needle to liquid configuration. Using an intensified charge-coupled device (ICCD), temporal evolution of the discharge between the two electrodes is investigated for the diffuse mode and the patterned mode, respectively. For the diffuse mode, the positive discharge is in a glow regime, and the negative discharge is in a Townsend discharge regime. For the patterned mode, the discharge always belongs to the Townsend discharge regime. Moreover, in the patterned mode, various patterns including the single loop, single loop with the surrounding corona, triple loops, and concentric loops with a central spot are observed on the water surface with the increasing positive peak-value of the applied voltage (Upp). Temporally resolved images of the loop-patterns are captured on the water surface. From the electrical measurements and the ICCD imaging, it is found that the loop pattern emerges after the discharge bridges the two electrodes. Then, it begins to evolve and finally degenerates with the decrease in the discharge current. The pattern does not disappear until the discharge quenches. Formation of the loop-patterns is attributed to the role of negative ions.

  3. Erosion protection by calcium lactate/sodium fluoride rinses under different salivary flows in vitro.

    Science.gov (United States)

    Borges, Alessandra B; Scaramucci, Taís; Lippert, Frank; Zero, Domenick T; Hara, Anderson T

    2014-01-01

    This study investigated the effect of a calcium lactate prerinse on sodium fluoride protection in an in vitro erosion-remineralization model simulating two different salivary flow rates. Enamel and dentin specimens were randomly assigned to 6 groups (n = 8), according to the combination between rinse treatments - deionized water (DIW), 12 mM NaF (NaF) or 150 mM calcium lactate followed by NaF (CaL + NaF) - and unstimulated salivary flow rates - 0.5 or 0.05 ml/min - simulating normal and low salivary flow rates, respectively. The specimens were placed into custom-made devices, creating a sealed chamber on the specimen surface connected to a peristaltic pump. Citric acid was injected into the chamber for 2 min, followed by artificial saliva (0.5 or 0.05 ml/min) for 60 min. This cycle was repeated 4×/day for 3 days. Rinse treatments were performed daily 30 min after the 1st and 4th erosive challenges, for 1 min each time. Surface loss was determined by optical profilometry. KOH-soluble fluoride and structurally bound fluoride were determined in specimens at the end of the experiment. Data were analyzed by 2-way ANOVA and Tukey tests (α = 0.05). NaF and CaL + NaF exhibited significantly lower enamel and dentin loss than DIW, with no difference between them for normal flow conditions. The low salivary flow rate increased enamel and dentin loss, except for CaL + NaF, which presented overall higher KOH-soluble and structurally bound fluoride levels. The results suggest that the NaF rinse was able to reduce erosion progression. Although the CaL prerinse considerably increased F availability, it enhanced NaF protection against dentin erosion only under hyposalivatory conditions.

  4. Decomposition of atrazine traces in water by combination of non-thermal electrical discharge and adsorption on nanofiber membrane.

    Science.gov (United States)

    Vanraes, Patrick; Willems, Gert; Daels, Nele; Van Hulle, Stijn W H; De Clerck, Karen; Surmont, Pieter; Lynen, Frederic; Vandamme, Jeroen; Van Durme, Jim; Nikiforov, Anton; Leys, Christophe

    2015-04-01

    In recent decades, several types of persistent substances are detected in the aquatic environment at very low concentrations. Unfortunately, conventional water treatment processes are not able to remove these micropollutants. As such, advanced treatment methods are required to meet both current and anticipated maximally allowed concentrations. Plasma discharge in contact with water is a promising new technology, since it produces a wide spectrum of oxidizing species. In this study, a new type of reactor is tested, in which decomposition by atmospheric pulsed direct barrier discharge (pDBD) plasma is combined with micropollutant adsorption on a nanofiber polyamide membrane. Atrazine is chosen as model micropollutant with an initial concentration of 30 μg/L. While the H2O2 and O3 production in the reactor is not influenced by the presence of the membrane, there is a significant increase in atrazine decomposition when the membrane is added. With membrane, 85% atrazine removal can be obtained in comparison to only 61% removal without membrane, at the same experimental parameters. The by-products of atrazine decomposition identified by HPLC-MS are deethylatrazine and ammelide. Formation of these by-products is more pronounced when the membrane is added. These results indicate the synergetic effect of plasma discharge and pollutant adsorption, which is attractive for future applications of water treatment. Copyright © 2014 Elsevier Ltd. All rights reserved.

  5. Observations of electric discharge streamer propagation and capillary oscillations on the surface of air bubbles in water

    Energy Technology Data Exchange (ETDEWEB)

    Sommers, B S; Foster, J E [Department of Nuclear Engineering and Radiological Science, University of Michigan, Ann Arbor, MI, 48109 (United States); Babaeva, N Yu; Kushner, Mark J [Department of Electrical Engineering and Computer Science, University of Michigan, Ann Arbor, MI, 48109 (United States)

    2011-03-02

    The propagation of electric discharge streamers inside bubbles in liquids is of interest for the remediation of toxins in water and plasma-based surgical instruments. The manner of streamer propagation has an important influence on the production of reactive species that are critical to these applications. Streamer propagation along the surface of electrode-attached bubbles of air in water, previously predicted by numerical simulations, has been experimentally imaged using a fast frame-rate camera. The successive pulsing of the streamer discharge inside the bubbles produced oscillations along the air-water interface. Subsequent streamers were observed to closely follow surface distortions induced by such oscillations. The oscillations likely arise from the non-uniform perturbation of the bubble driven by the electric field of the streamer and were found to be consistent with Kelvin's equation for capillary oscillations. For a narrow range of applied voltage pulse frequencies, the oscillation amplitude increased over several pulse periods indicating, potentially, resonant behaviour. We also observed coupling between bubbles wherein oscillations in a second bubble without an internal discharge were induced by the presence of a streamer in a fixed bubble. (fast track communication)

  6. The magnitude and origin of groundwater discharge to eastern U.S. and Gulf of Mexico coastal waters

    Science.gov (United States)

    Befus, Kevin; Kroeger, Kevin D.; Smith, Christopher G.; Swarzenski, Peter W.

    2017-01-01

    Fresh groundwater discharge to coastal environments contributes to the physical and chemical conditions of coastal waters, but the role of coastal groundwater at regional to continental scales remains poorly defined due to diverse hydrologic conditions and the difficulty of tracking coastal groundwater flow paths through heterogeneous subsurface materials. We use three-dimensional groundwater flow models for the first time to calculate the magnitude and source areas of groundwater discharge from unconfined aquifers to coastal waterbodies along the entire eastern U.S. We find that 27.1 km3/yr (22.8–30.5 km3/yr) of groundwater directly enters eastern U.S. and Gulf of Mexico coastal waters. The contributing recharge areas comprised ~175,000 km2 of U.S. land area, extending several kilometers inland. This result provides new information on the land area that can supply natural and anthropogenic constituents to coastal waters via groundwater discharge, thereby defining the subterranean domain potentially affecting coastal chemical budgets and ecosystem processes.

  7. The interaction with suspended and settled sedimentary materials of long-lived radionuclides discharged into United Kingdom coastal waters

    Science.gov (United States)

    Pentreath, R. J.

    1987-11-01

    Low-level liquid radioactive wastes are routinely discharged under authorization into United Kingdom coastal waters from nuclear reactor sites, from nuclear fuel reprocessing and fabrication plants, and from other facilities connected with the nuclear industries. The effluents contain a wide range of radionuclides, with greatly varying half-lives and in different chemical forms. The receiving environments are also markedly different. All of these factors need to be taken into account in order that the authorizations for discharge are based on a sound knowledge of the underlying environmental science as well as meeting the objectives of radiological protection. The largest research effort has been expended on the longer-lived nuclides discharged from the BNFL plant at Sellafield into the Irish Sea. These studies have focused on such aspects as the nature of the effluent, the dispersion of the soluble nuclides out of the Irish Sea, the retention of other nuclides within it, and the incorporation of radionuclides into settled sediments. Some comparisons have also been made between other sites by observing the concentrations of radionuclides in similar materials, at similar distances, per unit rate of discharge. Although these studies are useful in developing an understanding of the dynamics of radionuclides in coastal environments, it is essential to have a wider and more general knowledge if the long-term consequences of discharging radionuclides—or any other chemical waste—into coastal waters are to be fully evaluated. These consequences are assessed by the use of models which have, necessarily, to simplify many of the processes involved. It is therefore all the more important that the underlying science relating to the nature and behaviour of the wastes, and of the receiving environment, is fully explored, and that the assumptions used in the models can be satisfactorily validated.

  8. Methyldibromoglutaronitrile in rinse-off products causes allergic contact dermatitis

    DEFF Research Database (Denmark)

    Jensen, C D; Johansen, J D; Menné, T

    2004-01-01

    BACKGROUND: The frequency of sensitivity to the cosmetic preservative methyldibromoglutaronitrile (MDBGN) has increased significantly in Europe. Most cases of allergic contact dermatitis from MDBGN are caused by leave-on cosmetic products. The risk of developing allergic contact dermatitis from...... series of MDBGN to determine their patch test threshold values. RESULTS: Seven presensitized individuals (37%) developed allergic contact dermatitis from the soap containing MDBGN. The mean dose of MDBGN per application was 2.2 micro g cm-2 and the reactions appeared between days 6 and 34. All nine...... rinse-off products has been less studied. OBJECTIVES: To investigate the allergic response elicited in presensitized individuals from exposure to a rinse-off product preserved with the maximum permitted level of MDBGN. METHODS: Nineteen contact allergic individuals and nine controls participated...

  9. Formation of ROS and RNS in Water Electro-Sprayed through Transient Spark Discharge in Air and their Bactericidal Effects

    Czech Academy of Sciences Publication Activity Database

    Machala, Z.; Tarabová, B.; Hensel, K.; Doležalová, Eva; Šikurová, L.; Lukeš, Petr

    2013-01-01

    Roč. 10, č. 7 (2013), s. 649-659 ISSN 1612-8850 R&D Projects: GA AV ČR IAAX00430802; GA ČR(CZ) GD104/09/H080; GA MŠk(CZ) MEB0810116 Institutional support: RVO:61389021 Keywords : Plasma electrospray * water * bacteria * hydrogen peroxide * peroxynitrite * cold plasma * water electro-spray Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 2.964, year: 2013 http://dx.doi.org/10.1002/ppap.201200113

  10. Carbohydrate mouth rinse does not improve repeated sprint performance

    Directory of Open Access Journals (Sweden)

    Leandro Ricardo Altimari

    2013-09-01

    Full Text Available The objective of this study was to evaluate the effect of a carbohydrate mouth rinse on the repeated sprint ability (RSA of young soccer players. Nine youth soccer players (15.0 ± 1.5 years; 60.7 ± 4.84 kg; 1.72 ± 0.05 m; 20.5 ± 1.25 kg/m2 were selected. The athletes were submitted to an RSA test consisting of six sprints of 40 m (going/return = 20 m + 20 m, separated by 20 s of passive recovery, under three experimental conditions: carbohydrate mouth rinse (CHO or placebo (PLA and control (CON. The mouth rinses containing CHO or PLA were administered 5 min and immediately before the beginning of the test in doses of 100 mL. The best sprint time (RSAbest, mean sprint time (RSAmean, and drop-off in sprint performance (fatigue index were determined for the different treatments. One-not identify significant differences (p> 0.05 in RSAbest (CHO way ANOVA for repeated measures did = 7.30 ± 0.31 s; PLA = 7.30 ± 0.30 s; CON = 7.26 ±0.16 s, RSA mean (CHO = 7.71 ± 0.30 s; PLA = 7.71 ± 0.25 s; CON = 7.66 ± 0.24s, or fatigue index (CHO = 5.58 ± 2.16%; PLA = 5.77 ± 3.04%; CON = 5.55 ±3.72%. The results suggest that a carbohydrate mouth rinse does not improve the repeated sprint performance of young soccer players.

  11. The effects of gaseous bubble composition and gap distance on the characteristics of nanosecond discharges in distilled water

    KAUST Repository

    Hamdan, Ahmad

    2016-05-17

    Electric discharge in liquids with bubbles can reduce the energy consumption, which increases treatment efficiency. We present an experimental study of nanosecond discharges in distilled water bubbled with the monoatomic gas argon and with the polyatomic gases methane, carbon dioxide, and propane. We monitor the time evolution of the voltage and current waveforms, and calculate the injected charges to characterize the discharge. We establish a relationship between the injected charges and the shape of the plasma by time-resolved imaging to find that increasing the size of the gap reduces the injected charges. Moreover, we determine the plasma characteristics, including electron density, excitation temperatures (for atoms and ions), and rotational temperature of the OH and C2 radicals found in the plasma. Our space- and time-averaged measurements allow us to propose a spatial distribution of the plasma that is helpful for understanding the plasma dynamics necessary to develop and optimize applications based on nanosecond discharges in bubbled liquids. © 2016 IOP Publishing Ltd.

  12. Vessel Sewage Discharges

    Science.gov (United States)

    Vessel sewage discharges are regulated under Section 312 of the Clean Water Act, which is jointly implemented by the EPA and Coast Guard. This homepage links to information on marine sanitation devices and no discharge zones.

  13. Effect of various rinsing protocols after use of amine fluoride/stannous fluoride toothpaste on the bacterial composition of dental plaque.

    Science.gov (United States)

    van Loveren, C; Gerardu, V A M; Sissons, C H; van Bekkum, M; ten Cate, J M

    2009-01-01

    This clinical study evaluated the effect of different oral hygiene protocols on the bacterial composition of dental plaque. After a 2-week period of using fluoride-free toothpaste, 30 participants followed three 1-week experimental protocols, each followed by 2-week fluoride-free washout periods in a randomized crossover examiner-blind controlled trial. The 1-week experimental protocols comprised the use of AmF/SnF(2) toothpaste twice daily, after which participants either (1) rinsed with tap water, (2) did not rinse but only spat out the toothpaste, or (3) rinsed with an AmF/SnF(2) mouthwash. In the fluoride-free washout periods, the participants brushed their teeth with fluoride-free toothpaste without further instructions. Six hours after the last brushing (+/- rinsing) of each period, buccal plaque samples in the upper molar region were taken. The microbiota composition of the plaque samples was analyzed by checkerboard DNA:DNA hybridization. A statistically significant reduction was found in the total amount of DNA of the 39 major plaque species measured, and in the proportions of some acid-producing bacterial strains after the period having used the AmF/SnF(2) toothpaste + AmF/SnF(2) mouthrinsing. The results indicate that using the AmF/SnF(2) toothpaste and rinse combination could result in plaque of lower cariogenicity. Copyright 2009 S. Karger AG, Basel.

  14. Enhanced shock wave generation via pre-breakdown acceleration using water electrolysis in negative streamer pulsed spark discharges

    Science.gov (United States)

    Lee, Kern; Chung, Kyoung-Jae; Hwang, Y. S.

    2018-03-01

    This paper presents a method for enhancement of shock waves generated from underwater pulsed spark discharges with negative (anode-directed) subsonic streamers, for which the pre-breakdown process is accelerated by preconditioning a gap with water electrolysis. Hydrogen microbubbles are produced at the cathode by the electrolysis and move towards the anode during the preconditioning phase. The numbers and spatial distributions of the microbubbles vary with the amplitude and duration of each preconditioning pulse. Under our experimental conditions, the optimum pulse duration is determined to be ˜250 ms at a pulse voltage of 400 V, where the buoyancy force overwhelms the electric force and causes the microbubbles to be swept out from the water gap. When a high-voltage pulse is applied to the gap just after the preconditioning pulse, the pre-breakdown process is significantly accelerated in the presence of the microbubbles. At the optimum preconditioning pulse duration, the average breakdown delay is reduced by 87% and, more importantly, the energy consumed during the pre-breakdown period decreases by 83%. This reduced energy consumption during the pre-breakdown period, when combined with the morphological advantages of negative streamers, such as thicker and longer stalks, leads to a significant improvement in the measured peak pressure (˜40%) generated by the underwater pulsed spark discharge. This acceleration of pre-breakdown using electrolysis overcomes the biggest drawback of negative subsonic discharges, which is slow vapor bubble formation due to screening effects, and thus enhances the efficiency of the shock wave generation process using pulsed spark discharges in water.

  15. Comparison of the Streptococcus mutans and Lactobacillus colony count changes in saliva following chlorhexidine (0.12% mouth rinse, combination mouth rinse, and green tea extract (0.5% mouth rinse in children

    Directory of Open Access Journals (Sweden)

    Rahul J Hegde

    2017-01-01

    Full Text Available Background: Compounds present in green tea have been shown to inhibit the growth and activity of bacteria associated with oral infections. The purpose of this study was to compare the efficacy of chlorhexidine (0.12% mouth rinse and combination (chlorhexidine and sodium fluoride mouth rinse to that of green tea extract (0.5% mouth rinse in reducing the salivary count of Streptococcus mutans and Lactobacillus in children. Materials and Methods: The sample for the study consisted of 75 school children aged 8–12 years with four or more (decay component of decayed, missing, and filled teeth index. Children were divided randomly into three equal groups and were asked to rinse with the prescribed mouth rinse once daily for 2 weeks after breakfast under supervision. Nonstimulated whole salivary sample (2 ml was collected at baseline and postrinsing and tested for the colony forming units of S. mutans and Lactobacillus. Results: The results of the study indicate that there was a statistically significant reduction in S. mutans and lactobacilli count in all the three study groups. The statistically significant reduction in the mean S. mutans and lactobacilli counts were more in 0.12% chlorhexidine group than in the combination mouth rinse and 0.5% green tea mouth rinse group. There was no statistically significant difference in the reduction of S. mutans and lactobacilli count between combination mouth rinse group and 0.5% green tea mouth rinse group. Conclusion: Green tea mouth rinse can be a promising preventive therapy worldwide for the prevention of dental caries.

  16. Evaluation of a cost effective technique for treating aquaculture water discharge using Lolium perenne Lam as a biofilter.

    Science.gov (United States)

    Nduwimana, André; Yang, Xiang-Long; Wang, Li-Ren

    2007-01-01

    Wastewater stabilization ponds generate low cost by-products that are useful for agriculture. The utilization of these by-products for soil amendment and as a source of nutrients for plants requires a high level of sanitation and stabilization of the organic matter, to maintain acceptable levels of soil, water and air quality. In this study, two aquaculture wastewater treatment systems; recirculating system and a floating plant bed system were designed to improve the quality of irrigation water in local communities with low income. In both systems the grass species Lolium perenne Lam was used as a plant biofilter while vegetable specie Amaranthus viridis was used to evaluate the performance of the system and the suitability of the phyto-treated water for irrigation. It was found that the harmful material removal rate for recirculating system was 88.9% for TAN (total ammonia nitrogen), 90% for NO2(-)-N, 64.8% for NO3(-)-N while for floating plant bed system 82.7% for TAN, 82% for NO2(-)-N and 60.5% for NO3(-)-N. Comparative analysis of the efficiency of waste element removal between the two systems revealed that both systems performed well, however, plant growth was not robust for floating plant bed system while recirculating system is energy consuming. Although both systems did not attain sufficient levels of TN (total nitrogen) and TP (total phosphorus) load reduction, the treatment with L. perenne remarkably improved the irrigation water quality. A. viridis plants irrigated with the phyto-treated discharge water had lesser concentrations of heavy metals in their tissues compared to those irrigated with untreated discharge. The control plants irrigated with untreated discharge were also found to be highly lignified with few stems and small leaves.

  17. The study of contamination of discharged runoff from surface water disposal channels of Bushehr city in 2012-2013

    Directory of Open Access Journals (Sweden)

    Vaheid Noroozi-Karbasdehi

    2016-09-01

    Full Text Available Background: In coastal cities, wastewater discharge into the sea is one of the options for sewage disposal that in case of non-compliance with health standards  in wastewater disposal will be led to the spread of infection and disease. On the other hand, water resources preservation and using them efficiently are the principles of sustainable development of each country. This study was aimed to investigate the contamination of discharged runoff from the surface water disposal channels of Bushehr city in 2012 - 13. Materials and Methods: In this study, Sampling was conducted by composite sampling method from output of the five main surface water disposal channels leading to the Persian Gulf located in the coastal region of Bushehr city during two seasons including wet (winter and dry (summer in 2012- 13. Then, experimental tests of BOD5, total coliform and fecal coliform were done on any of the 96 samples according to the standard method. Results: Analysis of the data showed that the BOD5, total coliform and fecal coliform of effluent runoff of the channels were more than the national standard output of disposal wastewaters into the surface waters, and the highest and lowest amount of BOD5 which obtained were 160 mg/L and 28 mg/L, respectively. Conclusion: considering the fact that discharged runoff from surface water disposal channels link from shoreline to sea in close distance and they often are as natural swimming sites and even fishing sites of Bushehr city, and also according to high level of organic and bacterial load of these channels, it is urgently required to be considered by the authorities.

  18. Carbon-based nanomaterial synthesis using nanosecond electrical discharges in immiscible layered liquids: n-heptane and water

    Science.gov (United States)

    Hamdan, Ahmad; Cha, Min Suk

    2018-06-01

    Plasmas in- or in-contact with liquids have been extensively investigated due to their high potential for a wide range of applications including, but not limited to, water treatment, material synthesis and functionalization, bio-medical applications, and liquid fuel reformation. Recently, we successfully developed a discharge using two immiscible liquids, having very different electrical permittivities, which could significantly intensify the electric field intensity. Here, we establish nanosecond discharges at the interface n-heptane-water (with respective relative dielectric permittivities of 2 and 80) to enable the synthesis of carbon-based nanomaterials. A characterization of the as-synthesized material and the annealed (500 °C) material, using various techniques (Fourier-transform, infra-red, scanning and transmission electron microscopes, etc), shows that the as-synthesized material is a mixture of two carbon-based phases: a crystalline phase (graphite like) embedded into a phase of hydrogenated amorphous carbon. The existence of two-phases may be explained by the non-homogeneity of the discharge that induces various chemical reactions in the plasma channel.

  19. Carbon-based nanomaterial synthesis using nanosecond electrical discharges in immiscible layered liquids: n-heptane and water

    KAUST Repository

    Hamdan, Ahmad

    2018-05-14

    Plasmas in- or in-contact with liquids have been extensively investigated due to their high potential for a wide range of applications including but not limited to, water treatment, material synthesis and functionalization, bio-medical applications, and liquid fuel reformation. Recently, we successfully developed a discharge using two immiscible liquids, having very different electrical permittivities, which could significantly intensify the electric field intensity. Here, we establish nanosecond discharges at the interface n-heptane-water (with respective relative dielectric permittivities of 2 and 80) to enable the synthesis of carbon-based nanomaterials. A characterization of the as-synthesized material and the annealed (500 °C) material, using various techniques (Fourier-Transform, Infra-Red, Scanning and Transmission electron microscopes, etc.), shows that the as-synthesized material is a mixture of two carbon-based phases: a crystalline phase (graphite like) embedded into a phase of hydrogenated amorphous carbon. The existence of two-phases may be explained by the non-homogeneity of the discharge that induces various chemical reactions in the plasma channel.

  20. Electron density in surface barrier discharge emerging at argon/water interface: quantification for streamers and leaders

    Science.gov (United States)

    Cvetanović, Nikola; Galmiz, Oleksandr; Synek, Petr; Zemánek, Miroslav; Brablec, Antonín; Hoder, Tomáš

    2018-02-01

    Optical emission spectroscopy, fast intensified CCD imaging and electrical measurements were applied to investigate the basic plasma parameters of surface barrier discharge emerging from a conductive water electrode. The discharge was generated at the triple-line interface of atmospheric pressure argon gas and conductive water solution at the fused silica dielectrics using a sinusoidal high-voltage waveform. The spectroscopic methods of atomic line broadening and molecular spectroscopy were used to determine the electron densities and the gas temperature in the active plasma. These parameters were obtained for both applied voltage polarities and resolved spatially. Two different spectral signatures were identified in the spatially resolved spectra resulting in electron densities differing by two orders of magnitude. It is shown that two discharge mechanisms take a place: the streamer and the leader one, with electron densities of 1014 and 1016 cm-3, respectively. This spectroscopic evidence is supported by the combined diagnostics of electrical current measurements and phase-resolved intensified CCD camera imaging.

  1. Development of a numerical model for calculating exposure to toxic and nontoxic stressors in the water column and sediment from drilling discharges

    NARCIS (Netherlands)

    Rye, H.; Reed, M.; Frost, T.K.; Smit, M.G.D.; Durgut, S.

    2008-01-01

    Drilling discharges are complex mixtures of chemical components and particles which might lead to toxic and nontoxic stress in the environment. In order to be able to evaluate the potential environmental consequences of such discharges in the water column and in sediments, a numerical model was

  2. Method of preparing water purification membranes. [polymerization of allyl amine as thin films in plasma discharge

    Science.gov (United States)

    Hollahan, J. R.; Wydeven, T. J., Jr. (Inventor)

    1974-01-01

    Allyl amine and chemically related compounds are polymerized as thin films in the presence of a plasma discharge. The monomer compound can be polymerized by itself or in the presence of an additive gas to promote polymerization and act as a carrier. The polymerized films thus produced show outstanding advantages when used as reverse osmosis membranes.

  3. Emerging and Conventional Contaminants in River Waters Discharging into the Black Sea along the Ukrainian Coast

    Science.gov (United States)

    The major rivers of Ukraine, including the Dnieper, Dniester, Southern Bug and Danube, discharge approximately 8500 m3/s of freshwater into the northern and western portions of the Black Sea. As one of the largest countries in Europe, Ukraine also has one of the largest human po...

  4. Preston and Park-Sanders protocols adapted for semi-quantitative isolation of thermotolerant Campylobacter from chicken rinse

    DEFF Research Database (Denmark)

    Josefsen, Mathilde Hartmann; Lübeck, Peter Stephensen; Aalbaek, B.

    2003-01-01

    Human campylobacteriosis has become the major cause of foodborne gastrointestinal diseases in several European countries. In order to implement effective control measures in the primary production, and as a tool in risk assessment studies, it is necessary to have sensitive and quantitative...... detection methods. Thus, semi-quantitative detection of thermophilic Campylobacter spp. in 20 naturally contaminated chicken rinse samples was carried out using the two most common standard protocols: Preston and Park-Sanders, as proposed by Nordic Committee on Food Analysis (NMKL) and International...... Standard Organization (ISO), respectively. For both protocols, the chicken rinse samples were prepared in 500 ml buffered peptone water, as recommended in the ISO protocol no. 6887-2. The results indicated that the Preston protocol was superior to the Park-Sanders protocol in supporting growth...

  5. B, As, and F contamination of river water due to wastewater discharge of the Yangbajing geothermal power plant, Tibet, China

    Science.gov (United States)

    Guo, Qinghai; Wang, Yanxin; Liu, Wei

    2008-11-01

    Thermal waters from the Yangbajing geothermal field, Tibet, contain high concentrations of B, As, and F, up to 119, 5.7 and 19.6 mg/L, respectively. In this paper, the distribution of B, As, and F in the aquatic environment at Yangbajing was surveyed. The results show that most river water samples collected downstream of the Zangbo River have comparatively higher concentrations of B, As, and F (up to 3.82, 0.27 and 1.85 mg/L, respectively), indicating that the wastewater discharge of the geothermal power plant at Yangbajing has resulted in B, As, and F contamination in the river. Although the concentrations of B, As, and F of the Zangbo river waters decline downstream of the wastewater discharge site due to dilution effect and sorption onto bottom sediments, the sample from the conjunction of the Zangbo River and the Yangbajing River has higher contents of B, As, and F as compared with their predicted values obtained using our regression analysis models. The differences between actual and calculated contents of B, As, and F can be attributed to the contribution from upstream of the Yangbajing River. Water quality deterioration of the river has induced health problems among dwellers living in and downstream of Yangbajing. Effective measures, such as decontamination of wastewater and reinjection into the geothermal field, should be taken to protect the environment at Yangbajing.

  6. Modeling of experimental treatment of acetaldehyde-laden air and phenol-containing water using corona discharge technique.

    Science.gov (United States)

    Faungnawakij, Kajornsak; Sano, Noriaki; Charinpanitkul, Tawatchai; Tanthapanichakoon, Wiwut

    2006-03-01

    Acetaldehyde-laden air and phenol-contaminated water were experimentally treated using corona discharge reactions and gas absorption in a single water-film column. Mathematical modeling of the combined treatment was developed in this work. Efficient removal of the gaseous acetaldehyde was achieved while the corona discharge reactions produced short-lived species such as O and O- as well as ozone. Direct contact of the radicals and ions with water was known to produce aqueous OH radical, which contributes to the decomposition of organic contaminants: phenol, absorbed acetaldehyde, and intermediate byproducts in the water. The influence of initial phenol concentration ranging from 15 to 50 mg L(-1) and that of influent acetaldehyde ranging from 0 to 200 ppm were experimentally investigated and used to build the math model. The maximum energetic efficiency of TOC, phenol, and acetaldehyde were obtained at 25.6 x 10(-9) mol carbon J(-1), 25.0 x 10(-9) mol phenol J(-1), and 2.0 x 10(-9) mol acetaldehyde J(-1), respectively. The predictions for the decomposition of acetaldehyde, phenol, and their intermediates were found to be in good agreement with the experimental results.

  7. Industrial water resources management based on violation risk analysis of the total allowable target on wastewater discharge.

    Science.gov (United States)

    Yue, Wencong; Cai, Yanpeng; Xu, Linyu; Yang, Zhifeng; Yin, Xin'An; Su, Meirong

    2017-07-11

    To improve the capabilities of conventional methodologies in facilitating industrial water allocation under uncertain conditions, an integrated approach was developed through the combination of operational research, uncertainty analysis, and violation risk analysis methods. The developed approach can (a) address complexities of industrial water resources management (IWRM) systems, (b) facilitate reflections of multiple uncertainties and risks of the system and incorporate them into a general optimization framework, and (c) manage robust actions for industrial productions in consideration of water supply capacity and wastewater discharging control. The developed method was then demonstrated in a water-stressed city (i.e., the City of Dalian), northeastern China. Three scenarios were proposed according to the city's industrial plans. The results indicated that in the planning year of 2020 (a) the production of civilian-used steel ships and machine-made paper & paperboard would reduce significantly, (b) violation risk of chemical oxygen demand (COD) discharge under scenario 1 would be the most prominent, compared with those under scenarios 2 and 3, (c) the maximal total economic benefit under scenario 2 would be higher than the benefit under scenario 3, and (d) the production of rolling contact bearing, rail vehicles, and commercial vehicles would be promoted.

  8. Effect of air-water mixture drawoff from condenser discharge chamberson the Chernobylsk NPP turbine operating efficiency

    International Nuclear Information System (INIS)

    Trushin, V.N.; Aleksandrov, I.P.; Borets, V.I.

    1985-01-01

    It is established experimentally that reliable operation of air drawoffs from conden.ser discharge chambers influences greatly on efficiency of a cooling system of low-pressure condensers (LPC). The interacting influence of drawoff lines operating in parallel is outlined, which may, under certain conditions, lead to partial or total neutralization of the drawoff system, that, in its turn, leads to formation of a unique waterfall flow regime in the discharge chamber of LPC outside its partition. Waterfall regime leads to reduction of cooling water flow rate, to partial uncovering of. the fuel element cluster with the proper fall of vacuum and turbine efficiency. Experimental investigations, carried out at a condenser model, permit to find a way and give recommendations to prevent the formation of waterfall regime of outflow

  9. Behavior of water jet horizontally discharged from a small circular hole set on a circular pipe-surface into air

    International Nuclear Information System (INIS)

    Tsuyuki, Koji; Igarashi, Saburo; Sudo, Seiichi; Yamabe, Masahiro; Kikuchi, Akira; Oba, Risaburo

    2001-01-01

    In order to clarify the behavior of the water jet horizontally discharged from a small circular hole set on a circular pipe surface into air, in this paper, for the first step, we systematically observed the jet aspects, the efflux angle, the discharge coefficient and so on, when the hole diameter d is much smaller than the pipe diameter D. Since the upstream kinetic energy from the hole is somewhat higher than the downstream counterpart, the upstream partial jet with higher efflux angle crashes into the downstream partial jet and drives out the latter into up- and down-side, resulting in a marked pair of vortices, so that resulting in a three-dimensional spiral flow accompanying with marked surface waves. (author)

  10. The differential radiological impact of plutonium recycle in the light-water reactor fuel cycle: effluent discharges during normal operation

    International Nuclear Information System (INIS)

    Bouville, A.; Guetat, P.; Jones, J.A.; Kelly, G.N.; Legrand, J.; White, I.F.

    1980-01-01

    The radiological impact of a light-water reactor fuel cycle utilizing enriched uranium fuel may be altered by the recycle of plutonium. Differences in impact may arise during various operations in the fuel cycle: those which arise from effluents discharged during normal operation of the various installations comprising the fuel cycle are evaluated in this study. The differential radiological impact on the population of the European Communities (EC) of effluents discharged during the recycling of 10 tonnes of fissile plutonium metal is evaluated. The contributions from each stage of the fuel cycle, i.e. fuel fabrication, reactor operation and fuel reprocessing and conversion, are identified. Separate consideration is given to airborne and liquid effluents and account is taken of a wide range of environmental conditions, representative of the EC, in estimating the radiological impact. The recycle of plutonium is estimated to result in a reduction in the radiological impact from effluents of about 30% of that when using enriched uranium fuel

  11. Pulsed power supply and coaxial reactor applied to E. coli elimination in water by pulsed dielectric barrier discharge

    Energy Technology Data Exchange (ETDEWEB)

    Quiroz V, V. E.; Lopez C, R.; Rodriguez M, B. G.; Pena E, R.; Mercado C, A.; Valencia A, R.; Hernandez A, A. N.; Barocio, S. R.; Munoz C, A. E. [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico); De la Piedad B, A., E-mail: regulo.lopez@inin.gob.mx [Instituto Tecnologico de Toluca, Av. Tecnologico s/n, Ex-Rancho La Virgen, 52140 Metepec, Estado de Mexico (Mexico)

    2013-07-01

    The design and instrumentation intended for ATTC8739 Escherichia coli (E. coli) bacteria elimination in water, based on non thermal plasma generation at room pressure have been carried out by means of dielectric pulsed discharges. The latter have been produced by a power supply capable of providing voltages up to the order of 45 kV, 1-500 {mu}s pulse widths and variable frequencies between 100 Hz to 2000 Hz. This supply feeds a coaxial discharge reactor of the simple dielectric barrier type. The adequate operation of the system has been tested with the elimination of E. coli at 10{sup 4} and 10{sup 6} bacteria/ml concentrations, leading to reductions up to 85.3% and 95.1%, respectively, during the first 30 min of treatment. (Author)

  12. Relative invasion risk for plankton across marine and freshwater systems: examining efficacy of proposed international ballast water discharge standards.

    Directory of Open Access Journals (Sweden)

    Oscar Casas-Monroy

    Full Text Available Understanding the implications of different management strategies is necessary to identify best conservation trajectories for ecosystems exposed to anthropogenic stressors. For example, science-based risk assessments at large scales are needed to understand efficacy of different vector management approaches aimed at preventing biological invasions associated with commercial shipping. We conducted a landscape-scale analysis to examine the relative invasion risk of ballast water discharges among different shipping pathways (e.g., Transoceanic, Coastal or Domestic, ecosystems (e.g., freshwater, brackish and marine, and timescales (annual and per discharge event under current and future management regimes. The arrival and survival potential of nonindigenous species (NIS was estimated based on directional shipping networks and their associated propagule pressure, environmental similarity between donor-recipient ecosystems (based on salinity and temperature, and effects of current and future management strategies (i.e., ballast water exchange and treatment to meet proposed international biological discharge standards. Our findings show that current requirements for ballast water exchange effectively reduce invasion risk to freshwater ecosystems but are less protective of marine ecosystems because of greater environmental mismatch between source (oceanic and recipient (freshwater ecoregions. Future requirements for ballast water treatment are expected to reduce risk of zooplankton NIS introductions across ecosystem types but are expected to be less effective in reducing risk of phytoplankton NIS. This large-scale risk assessment across heterogeneous ecosystems represents a major step towards understanding the likelihood of invasion in relation to shipping networks, the relative efficacy of different invasion management regimes and seizing opportunities to reduce the ecological and economic implications of biological invasions.

  13. A water availability and low-flow analysis of the Tagliamento River discharge in Italy under changing climate conditions

    Directory of Open Access Journals (Sweden)

    L. N. Gunawardhana

    2012-03-01

    . Moreover, a consistent shift in river discharge timing would eventually cause snowmelt-generated river discharge to occur approximately 12 days earlier during the 2080–2099 time period compared to the baseline climate. These results are expected to raise the concern of policy makers, leading to the development of new water management strategies in the Tagliamento River basin to cope with changing climate conditions.

  14. Comparison of neck skin excision and whole carcass rinse sampling methods for determining Salmonella prevalence and E. coli counts on broiler carcasses before and after immersion chilling

    Science.gov (United States)

    A regulatory agency (FSIS) in the U.S. rinses whole broiler carcasses with 400 ml of 1% buffered peptone water (BPW) for Salmonella detection, while the European Union (EU) samples a 25g composited neck skin from three carcasses. The purpose of the study was to evaluate the FSIS and EU procedures fo...

  15. Identification of hazards for water environment in the Upper Silesian Coal Basin caused by the discharge of salt mine water containing particularly harmful substances and radionuclides

    Directory of Open Access Journals (Sweden)

    Jan Bondaruk

    2015-01-01

    Full Text Available The Upper Silesian urban-industrial agglomeration is one of the most industrialized areas in Europe. The intense industrialization should be attributed mostly to the presence of coal and other minerals deposits and its extraction. Mining areas of hard coal mines comprise approximately 25% of the total catchment area of watercourses in the area of Upper Silesian Coal Basin, including the river basin of the Upper Oder River and the Little Vistula River. The mining, its scope and depth, duration of mining works, extraction systems being used and the total volume of the drainage fundamentally affect the conditions of groundwater and surface water in the studied area. In this paper, an overall characteristics of the coal mining industry in the area of USCB was made, including the issues of its influence on water environment in the light of the requirements of the Water Framework Directive (WFD and its guidelines transposed into Polish law. An analysis of the collected data, obtained from collieries, relating to the quantity and quality of water flowing into the workings and discharged to surface watercourses, was performed. An approach to the requirements for wastewater discharge into the environment by these enterprises was presented regarding the physicochemical parameters, possible harmful substances and radionuclides measured in mine waters. The main goal of the paper is to recognize the condition of surface water bodies in the area of Upper Silesian Coal Basin and to make the assessment of the biological condition using Ecological Risk Assessment and bioindication methods.

  16. Discharge of water containing waste emanating from land to the marine environment: a water quality management perspective

    CSIR Research Space (South Africa)

    Oelofse, Suzanna HH

    2004-01-01

    Full Text Available that apply for such discharges in order for this country to retain international credibility. In this paper the authors provide a concise discussion on: The development of an operational policy providing the strategic view on marine disposal, as well...

  17. Nanosecond Pulsed Discharge in Water without Bubbles: A Fundamental Study of Initiation, Propagation and Plasma Characteristics

    Science.gov (United States)

    Seepersad, Yohan

    The state of plasma is widely known as a gas-phase phenomenon, but plasma in liquids have also received significant attention over the last century. Generating plasma in liquids however is theoretically challenging, and this problem is often overcome via liquid-gas phase transition preceding the actual plasma formation. In this sense, plasma forms in gas bubbles in the liquid. Recent work at the Drexel Plasma Institute has shown that nanosecond pulsed electric fields can initiate plasma in liquids without any initial cavitation phase, at voltages below theoretical direct-ionization thresholds. This unique regime is poorly understood and does not fit into any current descriptive mechanisms. As with all new phenomena, a complete fundamental description is paramount to understanding its usefulness to practical applications. The primary goals of this research were to qualitatively and quantitatively understand the phenomenon of nanosecond pulsed discharge in liquids as a means to characterizing properties that may open up niche application possibilities. Analysis of the plasma was based on experimental results from non-invasive, sub-nanosecond time-resolved optical diagnostics, including direct imaging, transmission imaging (Schlieren and shadow), and optical emission spectroscopy. The physical characteristics of the plasma were studied as a function of variations in the electric field amplitude and polarity, liquid permittivity, and pulse duration. It was found that the plasma size and emission intensity was dependent on the permittivity of the liquid, as well as the voltage polarity, and the structure and dynamics were explained by a 'cold-lightning' mechanism. The under-breakdown dynamics at the liquid-electrode interface were investigated by transmission imaging to provide evidence for a novel mechanism for initiation based on the electrostriction. This mechanism was proposed by collaborators on the project and developed alongside the experimental work in this

  18. Interactions of radionuclides in water, particulates, and oysters in the discharge canal of a nuclear power plant

    International Nuclear Information System (INIS)

    Harrison, F.L.; Wong, K.M.; Heft, R.E.

    1976-01-01

    This study was designed to provide data for dynamic modeling of radioactive pollutants in marine ecosystems adjacent to nuclear power plants. The data are relevant to the dynamics of radionuclide transfer among seawater, suspended particulates, sediments, and biota. Gamma-emitting radionuclides ( 54 Mn, 60 Co, 65 Zn, and 137 Cs) were followed in the water and particulates, as well as in oysters introduced into the discharge canal of the boiling water reactor of the Humboldt Bay Power Plant near Eureka, California. The liquid waste was introduced into the canal at irregular intervals and contained radionuclides at extremely low but variable concentrations. Radionuclides were determined in the oysters, water, and particulates after single releases (over about 6 hr) and over a long series of releases

  19. Importance of including small-scale tile drain discharge in the calibration of a coupled groundwater-surface water catchment model

    DEFF Research Database (Denmark)

    Hansen, Anne Lausten; Refsgaard, Jens Christian; Christensen, Britt Stenhøj Baun

    2013-01-01

    the catchment. In this study, a coupled groundwater-surface water model based on the MIKE SHE code was developed for the 4.7 km2 Lillebæk catchment in Denmark, where tile drain flow is a major contributor to the stream discharge. The catchment model was calibrated in several steps by incrementally including...... the observation data into the calibration to see the effect on model performance of including diverse data types, especially tile drain discharge. For the Lillebæk catchment, measurements of hydraulic head, daily stream discharge, and daily tile drain discharge from five small (1–4 ha) drainage areas exist....... The results showed that including tile drain data in the calibration of the catchment model improved its general performance for hydraulic heads and stream discharges. However, the model failed to correctly describe the local-scale dynamics of the tile drain discharges, and, furthermore, including the drain...

  20. Ecological effects of scrubber water discharge on coastal plankton: Potential synergistic effects of contaminants reduce survival and feeding of the copepod Acartia tonsa

    DEFF Research Database (Denmark)

    Koski, Marja; Stedmon, Colin; Trapp, Stefan

    2017-01-01

    and hydrocarbons. We investigated 1) the threshold concentrations of scrubber discharge water for survival, feeding and reproduction of the copepod Acartia tonsa, 2) whether the effects depend on the exposure route and 3) whether exposure to discharge water can be detected in field-collected organisms. A direct...... constituents could have synergistic effects on plankton productivity and bioaccumulation of metals, although the effects will depend on their dilution in the marine environment....

  1. Potential of pulsed corona discharges generated in water for the degradation of persistent pharmaceutical residues

    Czech Academy of Sciences Publication Activity Database

    Banaschik, R.; Lukeš, Petr; Jablonowski, H.; Hammer, M. U.; Weltmann, K.-D.; Kolb, J.F.

    2015-01-01

    Roč. 84, November (2015), s. 127-135 ISSN 0043-1354 R&D Projects: GA MŠk(CZ) LD14080 Grant - others:European Cooperation in Science and Technology(XE) COST TD1208 Institutional support: RVO:61389021 Keywords : Advanced oxidation * Non-thermal plasma * Ethinylestradiol * Diclofenac * Phenol * Hydroxyl radicals Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 5.991, year: 2015 http://www.sciencedirect.com/science/journal/00431354/84/supp/C

  2. Shock Waves Generated by an Electrical Discharge on Composite Electrode Immersed in Water With Different Conductivities

    Czech Academy of Sciences Publication Activity Database

    Stelmashuk, Vitaliy; Hoffer, Petr

    2012-01-01

    Roč. 40, č. 7 (2012), s. 1907-1912 ISSN 0093-3813 Institutional research plan: CEZ:AV0Z20430508 Keywords : Corona * impedance matching * shock waves Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 0.868, year: 2012 http://ieeexplore.ieee.org/xpl/articleDetails.jsp?tp=&arnumber=6205646&contentType=Journals+%26+ Magazines &queryText%3Dstelmashuk

  3. 33 CFR 338.2 - Activities involving the discharge of dredged or fill material into waters of the U.S.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Activities involving the discharge of dredged or fill material into waters of the U.S. 338.2 Section 338.2 Navigation and Navigable Waters CORPS OF ENGINEERS, DEPARTMENT OF THE ARMY, DEPARTMENT OF DEFENSE OTHER CORPS ACTIVITIES INVOLVING...

  4. Transport, speciation, toxicity, and treatability of highway stormwater discharged to receiving waters in Louisiana : [tech summary].

    Science.gov (United States)

    2013-01-01

    As centralized wastewater treatment continues to improve while increasingly replacing decentralized systems, urban : rainfall-runoff has become the leading contributor of water body impairments in the United States (USEPA, 1996). For : many water bod...

  5. Multi-model assessment of global hydropower and cooling water discharge potential under climate change

    NARCIS (Netherlands)

    van Vliet, M. T H; van Beek, L. P H|info:eu-repo/dai/nl/14749799X; Eisner, S.; Flörke, M.; Wada, Y.|info:eu-repo/dai/nl/341387819; Bierkens, M. F P|info:eu-repo/dai/nl/125022794

    2016-01-01

    Worldwide, 98% of total electricity is currently produced by thermoelectric power and hydropower. Climate change is expected to directly impact electricity supply, in terms of both water availability for hydropower generation and cooling water usage for thermoelectric power. Improved understanding

  6. A novel wound rinsing solution based on nano colloidal silver

    Directory of Open Access Journals (Sweden)

    Soheila Kordestani

    2014-10-01

    Full Text Available Objective(s: The present study aimed to investigate the antiseptic properties of a colloidal nano silver wound rinsing solution to inhibit a wide range of pathogens including bacteria, viruses and fungus present in chronic and acute wounds. Materials and Methods:The wound rinsing solution named SilvoSept® was prepared using colloidal nano silver suspension. Physicochemical properties, effectiveness against microorganism including  Staphylocoocous aureus ATCC 6538P, Pseudomonas aeruginosa ATCC 9027, Escherichia coli ATCC 8739 ,Candida albicans ATCC 10231, Aspergillus niger ATCC 16404, MRSA , Mycobacterium spp. , HSV-1 and H1N1, and biocompatibility tests were carried out according to relevant standards . Results: X-ray diffraction (XRD scan was performed on the sample and verify single phase of silver particles in the compound. The size of the silver particles in the solution, measured by dynamic light scattering (DLS techniqu, ranged 80-90 nm. Transmission electron microscopy (TEM revealed spherical shape with smooth surface of the silver nanoparticles. SilvoSept® reduced 5 log from the initial count of 107 CFU/mL of Staphylocoocous aureus ATCC 6538P, Pseudomonas aeruginosa ATCC 9027, Escherichia coli ATCC 8739, Candida albicans ATCC 10231, Aspergillus niger ATCC 16404, MRSA, Mycobacterium spp. Further assessments of SilvoSept solution exhibited a significant inhibition on the replication of HSV-1 and H1N1. The biocompatibility studies showed that the solution was non-allergic, non-irritant and noncytotoxic. Conclusion: Findings of the present study showed that SilvoSept® wound rinsing solution containing nano silver particles is an effective antiseptic solution against a wide spectrum of microorganism. This compound can be a suitable candidate for wound irrigation.   

  7. Methylisothiazolinone in rinse-off products causes allergic contact dermatitis

    DEFF Research Database (Denmark)

    Yazar, K; Lundov, Michael Dyrgaard; Faurschou, A

    2015-01-01

    the potential to cause allergic contact dermatitis. METHODS: Nineteen MI-allergic subjects and 19 controls without MI allergy applied two liquid hand soaps five times per day on areas of 5 × 10 cm(2) on the ventral side of their forearms. One soap contained 100 ppm MI, the maximum allowed concentration......BACKGROUND: In recent years, the prevalence of contact allergy to the preservative methylisothiazolinone (MI) has increased dramatically. Cosmetic products are one of the major sources of exposure. OBJECTIVES: To examine whether allowed concentrations of MI in cosmetic rinse-off products have...

  8. A randomized, double‑blind clinical study to assess the antiplaque and antigingivitis efficacy of Aloe vera mouth rinse

    Directory of Open Access Journals (Sweden)

    Bathini Chandrahas

    2012-01-01

    Full Text Available Aims: To evaluate the efficacy of Aloe Vera mouth rinse on experimental plaque accumulation and gingivitis. Materials and Methods: In this randomized, controlled, and double-blind study, a total of 148 systemically healthy subjects were screened in the age group of 18-25 years. Finally, 120 subjects were requested to abstain from oral hygiene (tooth brushing for 14 days and used a specially fabricated plaque guard. Following cessation of tooth brushing in the specified area, the subjects were randomly divided into Group A (test group who received 100% Aloe vera, Group B (negative control group who received placebo (distilled water, and Group C (positive control group who received 0.2% chlorhexidine. The rinse regimen began on the 15 th day and continued for 7 days. Plaque accumulation was assessed by Plaque Index (PI and gingivitis was assessed by Modified Gingival Index (MGI and Bleeding Index (BI at baseline (0, 7 th , 14 th , and 22 nd days. Results: There was statistically significant decrease in PI, MGI, and BI scores after the rinse regimen began in both Group A (test group and Group C (chlorhexidine compared with Group B. Mouth wash containing Aloe vera showed significant reduction of plaque and gingivitis but when compared with chlorhexidine the effect was less significant. Conclusion: Aloe vera mouthwash can be an effective antiplaque agent and with appropriate refinements in taste and shelf life can be an affordable herbal substitute for chlorhexidine.

  9. Ecotoxicological water assessment of an estuarine river from the Brazilian Northeast, potentially affected by industrial wastewater discharge.

    Science.gov (United States)

    de Melo Gurgel, Piatã; Navoni, Julio Alejandro; de Morais Ferreira, Douglisnilson; do Amaral, Viviane Souza

    2016-12-01

    Water pollution generated by industrial effluents discharge is a threat to the maintenance of aquatic ecosystems and human development. The Jundiai River estuarine, located in Northeast Brazil, receives an industrial pretreated effluent load from the city of Macaíba/RN/Brazil. The present study aimed to assess the water quality of this water reservoir through i) physicochemical characterization, ii) quantification of metal concentration and iii) by an ecotoxicological assessment carried out using Mysidopsis juniae and Pomacea lineata. The study was performed throughout the period comprising May to September 2014. Physicochemical variables such as chloride, total solids and electrical conductivity presented values in the waste discharge point, significantly different with those located out of the waste releasing point. Apart from that, metal concentration showed variable behavior throughout the monitored period. Levels of Al, Fe, Cu, Cd, Cr, Ni, Pb and Ag were over the considered guidelines. Both natural and anthropogenic sources seem to be involved in the resulting environmental scenario. A reduction in the fecundity rate (using Mysidopsis juniae) along with an increase in mortality rate (in both species) was observed ratifying the presence of toxic substances in this water reservoir. Moreover, a correlation analysis stated an association of the aforementioned toxicological effects with the delivery of industrial waste products. The ecotoxicological assessment performed highlighted the presence of toxic substance/s in water from the Jundiai River. Especially as a consequence of industrial activity, a fact that might threaten the bioma and, therefore, the human health of the population settled in the studied region. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. Long-term biomonitoring of a produced water discharge from the Cedar Cove degasification field, Alabama. January 1991

    Energy Technology Data Exchange (ETDEWEB)

    O' Neil, P.E.; Harris, S.C.; Mettee, M.F.; McGregor, S.W.; Shepard, T.E.

    1991-01-01

    Development of coalbed methane has become a major industry for the state of Alabama. In excess of 1,300 wells were producing methane by the end of July 1990. A byproduct of methane production is produced water containing elevated concentrations of chloride, sodium, iron and bicarbonate. These waters are currently permitted for discharge into streams or as a land application. The purpose of the study was to examine the long-term impacts of produced waters to streams relative to water-quality changes and aquatic biological effects. Distinct water-quality changes in the receiving stream were documented and consisted primarily of increased dissolved solids, changes in the pH regime and changes in the carbonate buffering system. In contrast, no significant or consistent detrimental change in the structure or function of the stream biological community could be detected. Subtle changes in biological community structure and composition were noted and most likely due to effects associated with algal productivity in settling lagoons. These changes, however, were within the boundaries of variation typically observed for the communities. Based on the results of this and earlier studies, it was concluded that the national water-quality criterion for chloride was protective of stream life as examined in the study.

  11. Impact modelling of water resources development and climate scenarios on Zambezi River discharge

    Directory of Open Access Journals (Sweden)

    Harald Kling

    2014-07-01

    New hydrological insights for the region: Comparisons between historical and future scenarios show that the biggest changes have already occurred. Construction of Kariba and CahoraBassa dams in the mid 1900s altered the seasonality and flow duration curves. Future irrigation development will cause decreases of a similar magnitude to those caused by current reservoir evaporation losses. The discharge is highly sensitive to small precipitation changes and the two climate models used give different signs for future precipitation change, suggestive of large uncertainty. The river basin model and database are available as anopen-online Decision Support System to facilitate impact assessments of additional climate or development scenarios.

  12. Testing of man-made overland-flow and wetlands systems for the treatment of discharged waters from oil and gas production operations in Wyoming

    International Nuclear Information System (INIS)

    Caswell, P.C.; Gelb, D.; Marinello, S.A.; Emerick, J.C.; Cohen, R.R.H.

    1992-01-01

    The quality of produced and discharged waters is of increasing concern as the overall quality of potable waters within many regions of the country becomes a critical issue. The impact of discharged waters on the downstream water quality, as well as the flora and fauna within a discharge zone, is dependent on the quality of the water ultimately released into the system. In many regions of the country, discharge permits are being re-evaluated and sometimes recalled due to the actual and perceived impact upon surface and subsurface waters, particularly those providing water utilized by the human population. The engineering, design and testing of a system to treat produced waters from oil operations in Wyoming is addressed in this study. This work was designed and performed by students and faculty in the Environmental Science and Engineering and Petroleum Engineering departments at the Colorado School of Mines. The system consists of overland flow units and a constructed wetlands unit. The system units can be independently evaluated. The water is drawn from active settling ponds above the test site. Produced waters are actively being discharged into the drainage basin. Waters flowing through the test units are likewise discharged after treatment. The system has been operational since June, 1991 and monthly sampling and testing will continue through March, 1992. Initial results having been very promising. Aeration, precipitation and bacterial activity in the overland flow and wetland units appears to nearly eliminate the sulfide problem present and significantly reduce the released radium concentration. These are the constituents of major concern although testing for other chemicals of concern, including hydrocarbon content is also analyzed

  13. Long-term effects of discharges of produced water the marine environment from petroleum-related activities at Sonda de Campeche, Gulf of México.

    Science.gov (United States)

    Schifter, I; González-Macías, C; Salazar-Coria, L; Sánchez-Reyna, G; González-Lozano, C

    2015-11-01

    Produced water from offshore oil platforms is a major source of oil and related chemicals into the sea. The large volume and high salinity of produced water could pose severe environmental impacts upon inadequate disposal. This study is based on direct field sampling of effluents released into the ocean in the years 2003 and 2013 at the Sonda de Campeche located in the southern part of the Gulf of Mexico. Metals and hydrocarbons were characterized in water, sediments, and fish tissues at the discharge site and compared with those obtained at two reference sites. Chemicals that exceeded risk-based concentrations in the discharge included the metals As, Pb, Cd, and Cr, and a variety of compounds polycyclic aromatic hydrocarbon (PAHs), including naphthalene, fluorenes, and low molecular weight PAHs. The values of low to high molecular weight polycyclic aromatic hydrocarbon (PAHs), and carbon preference index indicate that hydrocarbons in sediments of the discharge zone are originated from the produced water and combustion sources. Fish tissues at the discharge zone and reference site are contaminated with PAHs, dominated by 2- and 3-rings; 4-ring accounted for less than 1% of total PAHs (TPAHs) in 2003, but increased to 7% in 2013. Results suggest that, from 2003 to 2013, discharges of produced water have had a non-negligible impact on ecosystems at a regional level, so the possibility of subtle, cumulative effects from operational discharges should not be ignored.

  14. Pancreatitis - discharge

    Science.gov (United States)

    Chronic pancreatitis - discharge; Pancreatitis - chronic - discharge; Pancreatic insufficiency - discharge; Acute pancreatitis - discharge ... You were in the hospital because you have pancreatitis. This is a swelling of the pancreas. You ...

  15. Disposal of liquid radioactive waste - discharge of radioactive waste waters from hospitals

    International Nuclear Information System (INIS)

    Ludwieg, F.

    1976-01-01

    A survey is given about legal prescriptions in the FRG concerning composition and amount of the liquid waste substances and waste water disposal by emitting into the sewerage, waste water decay systems and collecting and storage of patients excretions. The radiation exposure of the population due to drainage of radioactive waste water from hospitals lower by more than two orders than the mean exposure due to nuclear-medical use. (HP) [de

  16. Linking the effects of land use change with water quality and discharge :an integrated approach

    OpenAIRE

    Fauss, Lynn Michael

    1992-01-01

    Hydrologic and water-quality equilibria are greatly affected by changing land use. This study presents a methodology that integrates the use of remote sensing, geographical information systems (GIS) and water-quality modeling. Archived aerial photography proved to be a valuable source of historical land use data. GIS technology was used to compile and analyze spatial data. A comprehensive watershed model was used to link the effects of land use change to water quali...

  17. Effect of xylitol, sodium fluoride and triclosan containing mouth rinse on Streptococcus mutans

    Directory of Open Access Journals (Sweden)

    Priya Subramaniam

    2011-01-01

    Full Text Available Introduction : Prevention of dental caries is one of the main strategies in contemporary pediatric dental practice. Mouth rinses are widely used as an adjunct to maintain oral hygiene. It is important for these products to be effective and safe for regular use in children. Objective : The aim of the study was to investigate the efficacy of a newly introduced xylitol, sodium fluoride and triclosan containing mouth rinse in reducing levels of plaque Streptococcus mutans and to compare it with that of a 0.12% chlorhexidine mouth rinse. Materials and Methods : Thirty children were randomly divided into two groups of 15 children each. Group I (study group was given a mouth rinse containing xylitol (5%, sodium fluoride (0.05% and triclosan (0.03% and Group II (control group was given a chlorhexidine (0.12% mouth rinse. Both mouth rinses were alcohol free. Mouth rinsing was carried out twice daily, half an hour after breakfast and half an hour following dinner, for a period of 21 days under the supervision of the investigator. Results: In both groups, there was a significant reduction in the mean S. mutans count at the end of 21 days (P < 0.001. No significant difference was observed between the two mouth rinses. Conclusion: The use of a low fluoride-xylitol based mouth rinse appears to be a suitable choice for regular use in children.

  18. Quantifying the anthropogenic and climatic contributions to changes in water discharge and sediment load into the sea: A case study of the Yangtze River, China.

    Science.gov (United States)

    Zhao, Yifei; Zou, Xinqing; Gao, Jianhua; Xu, Xinwanghao; Wang, Chenglong; Tang, Dehao; Wang, Teng; Wu, Xiaowei

    2015-12-01

    Based on data from the Datong hydrological station and 147 meteorological stations, the influences of climate change and human activities on temporal changes in water discharge and sediment load were examined in the Yangtze River basin from 1953 to 2010. The Mann-Kendall test, abrupt change test (Mann-Kendall and cumulative anomaly test), and Morlet wavelet method were employed to analyze the water discharge and sediment load data measured at the Datong hydrological station. The results indicated that the annual mean precipitation and water discharge exhibited decreasing trends of -0.0064 mm/10 yr and -1.41×10(8) m3/yr, respectively, and that the water sediment load showed a significant decreasing trend of -46.5×10(6) t/yr. Meanwhile, an abrupt change in the water discharge occurred in 2003. The sediment load also exhibited an abrupt change in 1985. From 1970 to 2010, the climate change and human activities contributed 72% and 28%, respectively, to the water discharge reduction. The human-induced decrease in the sediment load was 914.03×10(6) t/yr during the 1970s and 3301.79×10(6) t/yr during the 2000s. The contribution from human activities also increased from 71% to 92%, especially in the 1990s, when the value increased to 92%. Climate change and human activities contributed 14% and 86%, respectively, to the sediment load reduction. Inter-annual variations in water discharge and sediment load were affected by climate oscillations and human activities. The effect of human activities on the sediment load was considerably greater than those on water discharge in the Yangtze River basin. Copyright © 2015 Elsevier B.V. All rights reserved.

  19. Novel flow-through bioremediation system for removing nitrate from nursery discharge water.

    Science.gov (United States)

    Chris Wilson, P; Albano, Joseph P

    2013-11-30

    Nitrate losses in surface runoff water from nursery production areas can be significant. This study evaluated the potential use of microbial-based (denitrification), flow-through bioreactors for their nitrate-remediation ability. Duplicate bioreactor systems were constructed at a local foliage plant nursery. Each bioreactor system consisted of four 242 L tanks with connections alternating between bottom and top. Each tank was filled with approximately 113 L of Kaldness media to provide surface area for attachment of native microflora. Molasses was supplied as a carbon source for denitrification and water flow rates through the systems ranged from 5 to 18 L min(-1) during tests. Automatic water samplers were used to collect composite samples every 15 min from both the inflow and the exit flow water. Results indicate consistent removal of 80-100% of the nitrate flowing into the systems. Accumulation of ammoniacal and nitrite nitrogen did not occur, indicating that the nitrate-nitrogen was removed from the water, and not simply transformed into another water-soluble species. Occasions where removal rates were less than 80% were usually traced to faulty delivery of the carbon source. Results indicate that modular microbial-based bioremediation systems may be a useful tool for helping water managers meet stringent nitrogen water quality regulations, especially at nurseries with limited space for expansion of water retention facilities. Copyright © 2013 Elsevier Ltd. All rights reserved.

  20. Satellite Derived Water Quality Observations Are Related to River Discharge and Nitrogen Loads in Pensacola Bay, Florida

    Directory of Open Access Journals (Sweden)

    John C. Lehrter

    2017-09-01

    Full Text Available Relationships between satellite-derived water quality variables and river discharges, concentrations and loads of nutrients, organic carbon, and sediments were investigated over a 9-year period (2003–2011 in Pensacola Bay, Florida, USA. These analyses were conducted to better understand which river forcing factors were the primary drivers of estuarine variability in several water quality variables. Remote sensing reflectance time-series data were retrieved from the MEdium Resolution Imaging Spectrometer (MERIS and used to calculate monthly and annual estuarine time-series of chlorophyll a (Chla, colored dissolved organic matter (CDOM, and total suspended sediments (TSS. Monthly MERIS Chla varied from 2.0 mg m−3 in the lower region of the bay to 17.2 mg m−3 in the upper bay. MERIS CDOM and TSS exhibited similar patterns with ranges of 0.51–2.67 (m−1 and 0.11–8.9 (g m−3. Variations in the MERIS-derived monthly and annual Chla, CDOM, and TSS time-series were significantly related to monthly and annual river discharge and loads of nitrogen, organic carbon, and suspended sediments from the Escambia and Yellow rivers. Multiple regression models based on river loads (independent variables and MERIS Chla, CDOM, or TSS (dependent variables explained significant fractions of the variability (up to 62% at monthly and annual scales. The most significant independent variables in the regressions were river nitrogen loads, which were associated with increased MERIS Chla, CDOM, and TSS concentrations, and river suspended sediment loads, which were associated with decreased concentrations. In contrast, MERIS water quality variations were not significantly related to river total phosphorus loads. The spatially synoptic, nine-year satellite record expanded upon the spatial extent of past field studies to reveal previously unseen system-wide responses to river discharge and loading variation. The results indicated that variations in Pensacola Bay Chla

  1. Adsorbability Enhancement of Macroporous Resin by Dielectric Barrier Discharge Plasma Treatment to Phenol in Water

    Directory of Open Access Journals (Sweden)

    Shoufeng Tang

    2016-01-01

    Full Text Available In order to enhance the adsorption efficiency and economize the use of macroporous resin, we have treated it with the dielectric barrier discharge (DBD plasma to improve its adsorbing capacity for phenol. The effects of operation conditions, for instance, applied voltage, treated time, and air flow rate on resin, were investigated by adsorption kinetics and isotherms. Results showed that the adsorption data were in good agreement with the pseudo-second-order and Freundlich equation. Experimental results showed that the modified resin was 156.5 mg/g and 39.2% higher than the untreated sample, when the modified conditions were conducted for discharge voltage 20 kV, treatment time 45 min, and air flow rate 1.2 L/min. The resin was characterized by FTIR and nitrogen adsorption isotherms before and after the DBD processes. It was found that the reason for the enhancement of resin adsorbability was attributed to the DBD plasma changing the surface physical and chemical structure.

  2. Does localized recharge occur at a discharge area within the ground-water flow system of Yucca Mountain, Nevada?

    International Nuclear Information System (INIS)

    Czarnecki, J.B.; Kroitoru, L.; Ronen, D.; Magaritz, M.

    1992-01-01

    Studies done in 1984, at a central site on Franklin Lake playa (also known as Alkali Flat, a major discharge area of the ground-water flow system that includes Yucca Mountain, Nevada, the potential site of a high-level nuclear-waste repository) yield limited hydraulic-head and hydrochemical data from a 3-piezometer nest which indicated a slightly downward hydraulic gradient (-0.02) and decreasing concentration of dissolved solids with increasing depth. Hydraulic-head measurements in June, 1989 made at the piezometer nest showed a substantially larger downward gradient (-0.10) and a 0. 83-meter higher water level in the shallowest piezometer (3.29 meters deep), indicating the possibility of localized recharge. during the period of September-November, 1989, a multilevel sampler was used to obtain detailed hydrochemical profiles of the uppermost 1. 5 m of the saturated zone

  3. Influence of sodium carbonate on decomposition of formic acid by pulsed discharge plasma inside bubble in water

    Science.gov (United States)

    Iwabuchi, Masashi; Takahashi, Katsuyuki; Takaki, Koichi; Satta, Naoya

    2016-07-01

    The influence of sodium carbonate on the decomposition of formic acid by discharge inside bubbles in water was investigated experimentally. Oxygen or argon gases were injected into the water through a vertically positioned glass tube, in which the high-voltage wire electrode was placed to generate plasmas at low applied voltage. The concentration of formic acid was determined by ion chromatography. In the case of sodium carbonate additive, the pH increased owing to the decomposition of the formic acid. In the case of oxygen injection, the percentage of conversion of formic acid increased with increasing pH because the reaction rate of ozone with formic acid increased with increasing pH. In the case of argon injection, the percentage of conversion was not affected by the pH owing to the high rate loss of hydroxyl radicals.

  4. Traveltime and dispersion data, including associated discharge and water-surface elevation data, Kanawha River West Virginia, 1991

    Science.gov (United States)

    Wiley, J.B.

    1993-01-01

    This report presents results of a study by the U.S. Geological Survey, in cooperation with the Virginia Environmental Endowment, Marshall University Research Corporation, and the West Virginia Depart- ment of Environmental Protection, to evaluate traveltime of a soluble dye on the Kanawha River. The Kanawha River originates in south-central West Virginia and flows northwestward to the Ohio River. Knowledge of traveltime and dispersion of a soluble dye could help river managers mitigate effects of an accidental spill. Traveltime and dispersion data were collected from June 20 through July 4, 1991, when river discharges decreased from June 24 through July 3, 1991. Daily mean discharges decreased from 5,540 ft 3/s on June 24 to 2,790 ft3/s on July 2 at Kanawha Falls and from 5,680 ft3/s on June 24 to 3,000 ft3/s on July 2 at Charleston. Water-surface elevations in regulated pools indicated a loss of water storage during the period. A spill at Gauley Bridge under similar streamflow conditions of this study is estimated to take 15 days to move beyond Winfield Dam. Estimated time of passage (elapsed time at a particular location) at Marmet Dam and Winfield Dam is approximately 2.5 days and 5.5 days, respectively. The spill is estimated to spend 12 days in the Winfield pool.

  5. High-efficiency removal of NOx using dielectric barrier discharge nonthermal plasma with water as an outer electrode

    Science.gov (United States)

    Dan, ZHAO; Feng, YU; Amin, ZHOU; Cunhua, MA; Bin, DAI

    2018-01-01

    With the rapid increase in the number of cars and the development of industry, nitrogen oxide (NOx) emissions have become a serious and pressing problem. This work reports on the development of a water-cooled dielectric barrier discharge reactor for gaseous NOx removal at low temperature. The characteristics of the reactor are evaluated with and without packing of the reaction tube with 2 mm diameter dielectric beads composed of glass, ZnO, MnO2, ZrO2, or Fe2O3. It is found that the use of a water-cooled tube reduces the temperature, which stabilizes the reaction, and provides a much greater NO conversion efficiency (28.8%) than that obtained using quartz tube (14.1%) at a frequency of 8 kHz with an input voltage of 6.8 kV. Furthermore, under equivalent conditions, packing the reactor tube with glass beads greatly increases the NO conversion efficiency to 95.85%. This is because the dielectric beads alter the distribution of the electric field due to the influence of polarization at the glass bead surfaces, which ultimately enhances the plasma discharge intensity. The presence of the dielectric beads increases the gas residence time within the reactor. Experimental verification and a theoretical basis are provided for the industrial application of the proposed plasma NO removal process employing dielectric bead packing.

  6. Impacts of a high-discharge submarine sewage outfall on water quality in the coastal zone of Salvador (Bahia, Brazil).

    Science.gov (United States)

    Roth, F; Lessa, G C; Wild, C; Kikuchi, R K P; Naumann, M S

    2016-05-15

    Carbon and nitrogen stable isotopic signatures of suspended particulate organic matter and seawater biological oxygen demand (BOD) were measured along a coastal transect during summer 2015 to investigate pollution impacts of a high-discharge submarine sewage outfall close to Salvador, Brazil. Impacts of untreated sewage discharge were evident at the outfall site by depleted δ(13)Corg and δ(15)N signatures and 4-fold increased BOD rates. Pollution effects of a sewage plume were detectable for more than 6km downstream from the outfall site, as seasonal wind- and tide-driven shelf hydrodynamics facilitated its advective transport into near-shore waters. There, sewage pollution was detectable at recreational beaches by depleted stable isotope signatures and elevated BOD rates at high tides, suggesting high bacterial activity and increased infection risk by human pathogens. These findings indicate the urgent necessity for appropriate wastewater treatment in Salvador to achieve acceptable standards for released effluents and coastal zone water quality. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. PIV measurements of turbulent jet and pool mixing produced by a steam jet discharge in a subcooled water pool

    International Nuclear Information System (INIS)

    Choo, Yeon Jun; Song, Chul-Hwa

    2010-01-01

    This experimental research is on the fluid-dynamic features produced by a steam injection into a subcooled water pool. The relevant phenomena could often be encountered in water cooled nuclear power plants. Two major topics, a turbulent jet and the internal circulation produced by a steam injection, were investigated separately using a particle image velocimetry (PIV) as a non-intrusive optical measurement technique. Physical domains of both experiments have a two-dimensional axi-symmetric geometry of which the boundary and initial conditions can be readily and well defined. The turbulent jet experiments with the upward discharging configuration provide the parametric values for quantitatively describing a turbulent jet such as the self-similar velocity profile, central velocity decay, spreading rate, etc. And in the internal circulation experiments with the downward discharging configuration, typical flow patterns in a whole pool region are measured in detail, which reveals both the local and macroscopic characteristics of the mixing behavior in a pool. This quantitative data on the condensing jet-induced mixing behavior in a pool could be utilized as benchmarking for a CFD simulation of relevant phenomena.

  8. Multi-model assessment of global hydropower and cooling water discharge potential under climate change

    NARCIS (Netherlands)

    Vliet, van M.T.H.; Beek, van L.P.H.; Eisner, S.; Flörke, M.; Wada, Y.; Bierkens, M.F.P.

    2016-01-01

    Worldwide, 98% of total electricity is currently produced by thermoelectric power and hydropower. Climate change is expected to directly impact electricity supply, in terms of both water availability for hydropower generation and cooling water usage for thermoelectric power. Improved

  9. Water balance versus land surface model in the simulation of Rhine river discharges

    NARCIS (Netherlands)

    Hurkmans, R.T.W.L.; Moel, de H.; Aerts, J.C.J.H.; Troch, P.A.

    2008-01-01

    Accurate streamflow simulations in large river basins are crucial to predict timing and magnitude of floods and droughts and to assess the hydrological impacts of climate change. Water balance models have been used frequently for these purposes. Compared to water balance models, however, land

  10. Influence of oral rinsing on the exposure of salivary glands during radioiodine therapy

    International Nuclear Information System (INIS)

    Luetzen, U.; Silvia, P.; Zhao, Y.; Marx, M.; Winkler, C.; Zuhayra, M.

    2015-01-01

    Full text of publication follows. Aim: the salivary glands (SG) constitute a risk organ during a radioiodine therapy of thyroid. A possible side effect is xerostomia. This study investigates whether repeated rinsing of the mouth with water during radioiodine therapy significantly extracts I-131 from the circuit between saliva and the gastrointestinal tract, and thus whether radiation exposure of the patient's SG is reduced. Methods: the control group consisted of 45 patients, ages 32 to 81 years, (mean 62 years, 8 male, 37 female), and received radioiodine therapy without rinsing their mouths. An intervention group of 42 patients, ages 36 to 88 years, (mean 61 years, 8 male, 34 female), with a benign or malignant thyroid disease, were asked 15-17 hours after capsule administration to rinse their mouths hourly with water for the next two days. The intervention group (n = 42) was divided into three groups. A low-risk group (n = 22) received between 0.4 and 1.0 GBq I-131 (mean 0.746), a medium risk group (n = 15) between 1.2 and 2.0 GBq (mean 1.783), and the high-risk group (n = 5) between 3.0 and 6.0 GBq (mean 3.600) respectively. To assess the function of the SG, scintigrams were performed prior to and 3 months after the radioiodine therapy. The estimation of the activity in the gastrointestinal tract was performed using whole-body scintigraphy on the day of release. Both, the SG and the whole body (WB) scintigraphies were evaluated using the region-of-interest technique. Furthermore, the activity of the collected saliva was quantified using a calibrated well-type detector. Results: the mean values of the activity extracted into the water-saliva mixture were 0.72% ± 0.3% and 0.14% ± 0.05% of the applied dose on the first and second day after capsule administration respectively. The analysis of the SG scintigrams of the low and medium risk groups showed no significant decrease in salivary gland function. Only in the high-risk group a significant loss of

  11. Initial site characterisation of a dissolved hydrocarbon groundwater plume discharging to a surface water environment

    International Nuclear Information System (INIS)

    Westbrook, S.J.; Commonwealth Scientific and Industrial Research Organisation Land and Water, Wembley, WA; Davis, G.B.; Rayner, J.L.; Fisher, S.J.; Clement, T.P.

    2000-01-01

    Preliminary characterisation of a dissolved hydrocarbon groundwater plume flowing towards a tidally- and seasonally-forced estuarine system has been completed at a site in Perth, Western Australia. Installation and sampling of multiport boreholes enabled fine scale (0.5-m) vertical definition of hydrocarbon concentrations. Vertical electrical conductivity profiles from multiport and spear probe sampling into the river sediments indicated that two groundwater/river water interfaces or dispersion zones are present: (a) an upper dispersion zone between brackish river water and groundwater, and (b) a lower interface between groundwater and deeper saline water. On-line water level loggers show that near-shore groundwater levels are also strongly influence by tidal oscillation. Results from the initial site characterisation will be used to plan further investigations of contaminated groundwater/surface water interactions and the biodegradation processes occurring at the site

  12. Sediment filtration can reduce the N load of the waste water discharge - a full-scale lake experiment

    Science.gov (United States)

    Aalto, Sanni L.; Saarenheimo, Jatta; Karvinen, Anu; Rissanen, Antti J.; Ropponen, Janne; Juntunen, Janne; Tiirola, Marja

    2016-04-01

    European commission has obliged Baltic states to reduce nitrate load, which requires high investments on the nitrate removal processes and may increase emissions of greenhouse gases, e.g. N2O, in the waste water treatment plants. We used ecosystem-scale experimental approach to test a novel sediment filtration method for economical waste water N removal in Lake Keurusselkä, Finland between 2014 and 2015. By spatially optimizing the waste water discharge, the contact area and time of nitrified waste water with the reducing microbes of the sediment was increased. This was expected to enhance microbial-driven N transformation and to alter microbial community composition. We utilized 15N isotope pairing technique to follow changes in the actual and potential denitrification rates, nitrous oxide formation and dissimilatory nitrate reduction to ammonium (DNRA) in the lake sediments receiving nitrate-rich waste water input and in the control site. In addition, we investigated the connections between observed process rates and microbial community composition and functioning by using next generation sequencing and quantitative PCR. Furthermore, we estimated the effect of sediment filtration method on waste water contact time with sediment using the 3D hydrodynamic model. We sampled one year before the full-scale experiment and observed strong seasonal patterns in the process rates, which reflects the seasonal variation in the temperature-related mixing patterns of the waste water within the lake. During the experiment, we found that spatial optimization enhanced both actual and potential denitrification rates of the sediment. Furthermore, it did not significantly promote N2O emissions, or N retention through DNRA. Overall, our results indicate that sediment filtration can be utilized as a supplemental or even alternative method for the waste water N removal.

  13. Heart pacemaker - discharge

    Science.gov (United States)

    Cardiac pacemaker implantation - discharge; Artificial pacemaker - discharge; Permanent pacemaker - discharge; Internal pacemaker - discharge; Cardiac resynchronization therapy - discharge; CRT - discharge; ...

  14. Environmental Compliance Guide. Guidance manual for Department of Energy compliance with the Clean Water Act: National Pollutant Discharge Elimination System (NPDES)

    Energy Technology Data Exchange (ETDEWEB)

    1982-07-01

    This manual provides general guidance for Department of Energy (DOE) officials for complying with Sect. 402 of the Clean Water Act (CWA) of 1977 and amendments. Section 402 authorizes the US Environmental Protection Agency (EPA) or states with EPA approved programs to issue National Pollutant Discharge Elimination System (NPDES) permits for the direct discharge of waste from a point source into waters of the United States. Although the nature of a project dictates the exact information requirements, every project has similar information requirements on the environmental setting, type of discharge(s), characterization of effluent, and description of operations and wastewater treatment. Additional information requirements for projects with ocean discharges, thermal discharges, and cooling water intakes are discussed. Guidance is provided in this manual on general methods for collecting, analyzing, and presenting information for an NPDES permit application. The NPDES program interacts with many sections of the CWA; therefore, background material on pertinent areas such as effluent limitations, water quality standards, toxic substances, and nonpoint source pollutants is included in this manual. Modifications, variances, and extensions applicable to NPDES permits are also discussed.

  15. Development of a numerical model for calculating exposure to toxic and nontoxic stressors in the water column and sediment from drilling discharges.

    Science.gov (United States)

    Rye, Henrik; Reed, Mark; Frost, Tone Karin; Smit, Mathijs G D; Durgut, Ismail; Johansen, Øistein; Ditlevsen, May Kristin

    2008-04-01

    Drilling discharges are complex mixtures of chemical components and particles which might lead to toxic and nontoxic stress in the environment. In order to be able to evaluate the potential environmental consequences of such discharges in the water column and in sediments, a numerical model was developed. The model includes water column stratification, ocean currents and turbulence, natural burial, bioturbation, and biodegradation of organic matter in the sediment. Accounting for these processes, the fate of the discharge is modeled for the water column, including near-field mixing and plume motion, far-field mixing, and transport. The fate of the discharge is also modeled for the sediment, including sea floor deposition, and mixing due to bioturbation. Formulas are provided for the calculation of suspended matter and chemical concentrations in the water column, and burial, change in grain size, oxygen depletion, and chemical concentrations in the sediment. The model is fully 3-dimensional and time dependent. It uses a Lagrangian approach for the water column based on moving particles that represent the properties of the release and an Eulerian approach for the sediment based on calculation of the properties of matter in a grid. The model will be used to calculate the environmental risk, both in the water column and in sediments, from drilling discharges. It can serve as a tool to define risk mitigating measures, and as such it provides guidance towards the "zero harm" goal.

  16. Monitoring Water Levels and Discharges Using Radar Altimetry in an Ungauged River Basin: The Case of the Ogooué

    Directory of Open Access Journals (Sweden)

    Sakaros Bogning

    2018-02-01

    Full Text Available Radar altimetry is now commonly used for the monitoring of water levels in large river basins. In this study, an altimetry-based network of virtual stations was defined in the quasi ungauged Ogooué river basin, located in Gabon, Central Africa, using data from seven altimetry missions (Jason-2 and 3, ERS-2, ENVISAT, Cryosat-2, SARAL, Sentinel-3A from 1995 to 2017. The performance of the five latter altimetry missions to retrieve water stages and discharges was assessed through comparisons against gauge station records. All missions exhibited a good agreement with gauge records, but the most recent missions showed an increase of data availability (only 6 virtual stations (VS with ERS-2 compared to 16 VS for ENVISAT and SARAL and accuracy (RMSE lower than 1.05, 0.48 and 0.33 and R² higher than 0.55, 0.83 and 0.91 for ERS-2, ENVISAT and SARAL respectively. The concept of VS is extended to the case of drifting orbits using the data from Cryosat-2 in several close locations. Good agreement was also found with the gauge station in Lambaréné (RMSE = 0.25 m and R2 = 0.96. Very good results were obtained using only one year and a half of Sentinel-3 data (RMSE < 0.41 m and R2 > 0.89. The combination of data from all the radar altimetry missions near Lamabréné resulted in a long-term (May 1995 to August 2017 and significantly improved water-level time series (R² = 0.96 and RMSE = 0.38 m. The increase in data sampling in the river basin leads to a better water level peak to peak characterization and hence to a more accurate annual discharge over the common observation period with only a 1.4 m3·s−1 difference (i.e., 0.03% between the altimetry-based and the in situ mean annual discharge.

  17. Temporal 222Rn distributions to reveal groundwater discharge into desert lakes: Implication of water balance in the Badain Jaran Desert, China

    Science.gov (United States)

    Luo, Xin; Jiao, Jiu Jimmy; Wang, Xu-sheng; Liu, Kun

    2016-03-01

    How lake systems are maintained and water is balanced in the lake areas in the Badain Jaran Desert (BJD), northeast of China have been debated for about a decade. In this study, continuous 222Rn measurement is used to quantify groundwater discharge into two representative fresh and brine water lakes in the desert using a steady-state mass-balance model. Two empirical equations are used to calculate atmospheric evasion loss crossing the water-air interface of the lakes. Groundwater discharge rates yielded from the radon mass balance model based on the two empirical equations are well correlated and of almost the same values, confirming the validity of the model. The fresh water and brine lakes have a daily averaged groundwater discharge rate of 7.6 ± 1.7 mm d-1 and 6.4 ± 1.8 mm d-1, respectively. The temporal fluctuations of groundwater discharge show similar patterns to those of the lake water level, suggesting that the lakes are recharged from nearby groundwater. Assuming that all the lakes have the same discharge rate as the two studied lakes, total groundwater discharge into all the lakes in the desert is estimated to be 1.59 × 105 m3 d-1. A conceptual model of water balance within a desert lake catchment is proposed to characterize water behaviors within the catchment. This study sheds lights on the water balance in the BJD and is of significance in sustainable regional water resource utilization in such an ecologically fragile area.

  18. Salinization and dilution history of ground water discharging into the Sea of Galilee, the Dead Sea Transform, Israel

    International Nuclear Information System (INIS)

    Bergelson, G.; Nativ, R.; Bein, A.

    1999-01-01

    The mechanism governing salinization of ground water discharging into the Sea of Galilee in Israel has been the subject of debate for several decades. Because the lake provides 25% of the water consumed annually in Israel, correct identification of the salt sources is essential for the establishment of suitable water-management strategies for the lake and the ground water in the surrounding aquifers. Existing salinization models were evaluated in light of available and newly acquired data including general chemistry, and O, H, C and Cl isotopes. Based on the chemical and isotopic observations, the proposed salt source is an ancient, intensively evaporated brine (21- to 33-fold seawater) which percolated through the valley formations from a lake which had formed in the Rift Valley following seawater intrusion during the late Miocene. Low Na:Cl and high Br:Cl values support the extensive evaporation, whereas high Ca:Cl and low Mg:Cl values indicate the impact of dolomitization of the carbonate host rock on the residual solution. Based on radiocarbon and other isotope data, the dilution of the original brine occurred in two stages: the first took place similar30andpuncsp; omitted000 a ago by slightly evaporated fresh-to-brackish lake water to form the Sea of Galilee Brine. The second dilution phase is associated with the current hydrological regime as the Sea of Galilee Brine migrates upward along the Rift faults and mixes with the actively circulating fresh ground water to form the saline springs. The spatially variable chemical and isotopic features of the saline springs suggest not only differential dilution by fresh meteoric water, but also differential percolation timing of the original brine into the tectonically disconnected blocks, registering different evaporation stages in the original brine. Consequently, various operations to reduce the brine contribution to the lake may be differentially effective in the various areas. (Copyright (c) 1999 Elsevier Science

  19. Natural radionuclides in waste water discharged from coal-fired power plants in Serbia.

    Science.gov (United States)

    Janković, Marija M; Todorović, Dragana J; Sarap, Nataša B; Krneta Nikolić, Jelena D; Rajačić, Milica M; Pantelić, Gordana K

    2016-12-01

    Investigation of the natural radioactivity levels in water around power plants, as well as in plants, coal, ash, slag and soil, and to assess the associated radiation hazard is becoming an emerging and interesting topic. This paper is focused on the results of the radioactivity analysis in waste water samples from five coal-fired power plants in Serbia (Nikola Tesla A, Nikola Tesla B, Kolubara, Morava and Kostolac), which were analyzed in the period 2003-2015. River water samples taken upstream and downstream from the power plants, drain water and overflow water were analyzed. In the water samples gamma spectrometry analysis was performed as well as determination of gross alpha and beta activity. Natural radionuclide 40 K was detected by gamma spectrometry, while the concentrations of other radionuclides, 226 Ra, 235 U and 238 U, usually were below the minimum detection activity (MDA). 232 Th and artificial radionuclide 137 Cs were not detected in these samples. Gross alpha and beta activities were determined by the α/β low level proportional counter Thermo Eberline FHT 770 T. In the analyzed samples, gross alpha activity ranged from MDA to 0.47 Bq L - 1 , while the gross beta activity ranged from MDA to 1.55 Bq L - 1 .

  20. Submarine groundwater discharge as an important nutrient source influencing nutrient structure in coastal water of Daya Bay, China

    Science.gov (United States)

    Wang, Xuejing; Li, Hailong; Zheng, Chunmiao; Yang, Jinzhong; Zhang, Yan; Zhang, Meng; Qi, Zhanhui; Xiao, Kai; Zhang, Xiaolang

    2018-03-01

    As an important nutrient source for coastal waters, submarine groundwater discharge (SGD) has long been largely ignored in Daya Bay, China. In this study, we estimate the fluxes of SGD and associated nutrients into this region using a 224Ra mass balance model and assess the contribution/importance of nutrients by SGD, benthic sediments, local rivers, and atmospheric deposition. The results of 224Ra mass balance show that the estimated SGD ranges from (2.76 ± 1.43) × 106 m3/d to (1.03 ± 0.53) × 107 m3/d with an average of (6.32 ± 2.42) × 106 m3/d, about 16 times the total discharge rate of local rivers. The nutrient loading from SGD is estimated to be (1.05-1.99) × 105 mol/d for NO3-N, (4.04-12.16) × 103 mol/d for DIP, and (3.54-11.35) × 105 mol/d for Si. Among these considered nutrient sources, we find that SGD is the primary source for Si and NO3-N, contributing 68% and 42% of all considered sources, respectively. The atmospheric NO3-N flux is comparable to that from SGD. The local rivers are the most important source for DIP, contributing 75% of all considered sources. SGD with high N:P ratio (NO3-N/DIP) of 37.0 delivers not only a large quantity of nutrients, but also changes nutrient structure in coastal water. Based on a DIP budget, primary productivity is evaluated to be 54-73 mg C/m2 d, in which SGD accounts for approximately 30% of total production. This study indicates that SGD is a key source of nutrients to coastal waters and may cause an obvious change of primary production and nutrient structure in Daya Bay.

  1. Measuring the Thermal Conductivity of Sediments for the Estimation of Groundwater Discharge to Surface Waters with Temperature Probes

    Science.gov (United States)

    Duque, C.; Müller, S.; Sebok, E.; Engesgaard, P. K.

    2015-12-01

    Using temperature probes is a common exploratory method for studying groundwater-surface water interaction due to the ease for collecting measurements and the simplicity of the different analytical solutions. This approach requires to define the surface water temperature, the groundwater temperature and a set of parameters (density and specific capacity of water, and thermal conductivity of sediments) that can be easily extracted from tabulated values under the assumption that they are homogeneous in the study area. In the case of the thermal conductivity, it is common to apply a standard value of 1.84 Wm-1 C-1 corresponding to sand. Nevertheless the environments where this method is applied, like streambeds or lake/lagoons shores, are sedimentary depositional systems with high energy and biological activity that often lead to sediments dominated by organic matter or sharp changes in grain size modifying greatly the thermal conductivity values. In this study, the thermal conductivity was measured in situ along transects where vertical temperature profiles were collected in a coastal lagoon bed receiving groundwater discharge (Ringkøbing Fjord, Denmark). A set of 4 transects with 10-20 temperature profiles during 3 different seasons was analyzed together with more than 150 thermal conductivity measurements along the working transects and in experimental parcels of 1 m2 where the cm scale spatial variability of the thermal conductivity was assessed. The application of a literature-based bulk thermal conductivity of 1.84 Wm-1 C-1 instead of field data that ranged from 0.62 to 2.19 Wm-1 C-1, produced a mean flux overestimation of 2.33 cm d-1 that, considering the low fluxes of the study area, represents an increase of 89 % and up to a factor of 3 in the most extreme cases. The changes in thermal conductivity can alter the estimated fluxes hindering the detection of patterns in groundwater discharge and modifying the interpretation of the results.

  2. Produced water treatment and discharge solutions in TRANSPETRO maritime terminals; Solucoes de tratamento e descarte de agua produzida nos terminais aquaviarios da TRANSPETRO

    Energy Technology Data Exchange (ETDEWEB)

    Mansor, Leonardo Mitidiero; Burburan, Alexandre; Rodrigues, Fernanda Fonseca; Cerqueira, Ana Claudia F.P. de [TRANSPETRO - PETROBRAS Transporte S.A., Rio de Janeiro, RJ (Brazil); Padilha, Carlos Frederico [PETROBRAS, Rio de Janeiro, RJ (Brazil)

    2008-07-01

    The PETROBRAS produced water programme, conducted by PETROBRAS S.A. is the response to the challenge faced in handling, treating and discharging produced water associated to oil production that comes from Campos Basin mainly. After run modeling studies in oil and produced water associated through 2015 scenario, it was identified the total amount of produced water that will be handle monthly, increasing from 215.000 m{sup 3} up to 420.000 m{sup 3}. To achieve the goals of treating e discharging that huge amount of water, the program understood the following main actions: built 5 produced water plants (Sao Sebastiao, Macae-Cabiunas, Angra dos Reis, Sao Francisco do Sul and Osorio) and 2 reinjection sites (Cabiunas and Lagoa Parda). These plants and sites will be able to treat monthly the total produced water amount of 677.000 m{sup 3}. (author)

  3. Tiny Stowaways: Analyzing the Economic Benefits of a U.S. Environmental Protection Agency Permit Regulating Ballast Water Discharges

    Science.gov (United States)

    Lovell, Sabrina J.; Drake, Lisa A.

    2009-03-01

    The U.S. Environmental Protection Agency has proposed permitting ballast water discharges—a benefit of which would be to reduce the economic damages associated with the introduction and spread of aquatic invasive species. Research on ship-borne aquatic invasive species has been conducted in earnest for decades, but determining the economic damages they cause remains troublesome. Furthermore, with the exception of harmful algal blooms, the economic consequences of microscopic invaders have not been studied, despite their potentially great negative effects. In this paper, we show how to estimate the economic benefits of preventing the introduction and spread of harmful bacteria, microalgae, and viruses delivered in U.S. waters. Our calculations of net social welfare show the damages from a localized incident, cholera-causing bacteria found in shellfish in the Gulf of Mexico, to be approximately 706,000 (2006). On a larger scale, harmful algal species have the potential to be transported in ships’ ballast tanks, and their effects in the United States have been to reduce commercial fisheries landings and impair water quality. We examine the economic repercussions of one bloom-forming species. Finally, we consider the possible translocation within the Great Lakes of a virus that has the potential to harm commercial and recreational fisheries. These calculations illustrate an approach to quantifying the benefits of preventing invasive aquatic microorganisms from controls on ballast water discharges.

  4. Water treatments in semi-closed cooling circuits and their impact on the quality of effluents discharged by CERN

    CERN Document Server

    Santos Leite Cima Gomes, J; Kleiner, S

    2008-01-01

    The main goal of this study is to assess the impact of the discharges of the semi-closed water cooling circuits of CERN (European Center for Nuclear Research) on the overall quality of CERN's effluents, taking as guidelines the international legislation supported on the knowledge of the water systems of CERN. In order to reach this goal, a thorough analysis of the functioning of the semi-closed water cooling systems of CERN's particle accelerators was done, as well as, an analysis of the treatment that is done to prevent the proliferation of bacteria such as Legionella. The products used in these water treatments, as well as their impact, were also researched. In addition, a study of the applicable regulation to CERN's effluent was done. This study considered not only the regulation of France and Switzerland (CERN's host states) but also the international regulation from the European community, Portugal Germany, Spain, U.S. and Canada, having in view a better understanding of the limit values of the parameter...

  5. A new, rapid and reliable method for the determination of reduced sulphur (S2-) species in natural water discharges

    International Nuclear Information System (INIS)

    Montegrossi, Giordano; Tassi, Franco; Vaselli, Orlando; Bidini, Eva; Minissale, Angelo

    2006-01-01

    The determination of reduced S species in natural waters is particularly difficult due to their high instability and chemical and physical interferences in the current analytical methods. In this paper a new, rapid and reliable analytical procedure is presented, named the Cd-IC method, for their determination as ΣS 2- via oxidation to SO 4 2- after chemical trapping with an ammonia-cadmium solution that allows precipitation of all the reduced S species as CdS. The S 2- -SO 4 is analysed by ion-chromatography. The main advantages of this method are: low cost, high stability of CdS precipitate, absence of interferences, low detection limit (0.01mg/L as SO 4 for 10mL of water) and low analytical error (about 5%). The proposed method has been applied to more than 100 water samples from different natural systems (water discharges and cold wells from volcanic and geothermal areas, crater lakes) in central-southern Italy

  6. Mouth rinsing with a carbohydrate solution attenuates exercise-induced decline in executive function.

    Science.gov (United States)

    Konishi, Kana; Kimura, Tetsuya; Yuhaku, Atsushi; Kurihara, Toshiyuki; Fujimoto, Masahiro; Hamaoka, Takafumi; Sanada, Kiyoshi

    2017-01-01

    A decline in executive function could have a negative influence on the control of actions in dynamic situations, such as sports activities. Mouth rinsing with a carbohydrate solution could serve as an effective treatment for preserving the executive function in exercise. The purpose of this study was to examine the effects of mouth rinsing with a carbohydrate solution on executive function after sustained moderately high-intensity exercise. Eight young healthy participants completed 65 min of running at 75% V̇O 2 max with two mouth-rinsing conditions: with a carbohydrate solution (CHO) or with water (CON). Executive function was assessed before and after exercise by using the incongruent task of the Stroop Color and Word Test. The levels of blood glucose; and plasma adrenocorticotropic hormone (ACTH), epinephrine, and norepinephrine (NE) were evaluated. A two-way repeated-measures ANOVA, with condition (CHO and CON) and time (pre-exercise and post-exercise) as factors, was used to examine the main and interaction effects on the outcome measures. The reaction time in the incongruent condition of the Stroop test significantly increased after exercise in CON (pre-exercise 529 ± 45 ms vs. post-exercise 547 ± 60 ms, P  = 0.029) but not in CHO (pre-exercise 531 ± 54 ms vs. post-exercise 522 ± 80 ms), which resulted in a significant interaction (condition × time) on the reaction time ( P  = 0.028). The increased reaction time in CON indicates a decline in the executive function, which was attenuated in CHO. Increases in plasma epinephrine and NE levels demonstrated a trend toward attenuation accompanying CHO ( P  exercise, and that such attenuation seems to be unrelated to carbohydrate metabolic pathway but rather attributed, in part, to the inhibition of the excessive release of stress hormones.

  7. Evolution of concentration-discharge relations revealed by high frequency diurnal sampling of stream water during spring snowmelt

    Science.gov (United States)

    Olshansky, Y.; White, A. M.; Thompson, M.; Moravec, B. G.; McIntosh, J. C.; Chorover, J.

    2017-12-01

    Concentration discharge (C-Q) relations contain potentially important information on critical zone (CZ) processes including: weathering reactions, water flow paths and nutrient export. To examine the C-Q relations in a small (3.3 km2) headwater catchment - La Jara Creek located in the Jemez River Basin Critical Zone Observatory, daily, diurnal stream water samples were collected during spring snow melt 2017, from two flumes located in outlets of the La Jara Creek and a high elevation zero order basin within this catchment. Previous studies from this site (McIntosh et al., 2017) suggested that high frequency sampling was needed to improve our interpretation of C-Q relations. The dense sampling covered two ascending and two descending limbs of the snowmelt hydrograph, from March 1 to May 15, 2017. While Na showed inverse correlation (dilution) with discharge, most other solutes (K, Mg, Fe, Al, dissolved organic carbon) exhibited positive (concentration) or chemostatic trends (Ca, Mn, Si, dissolved inorganic carbon and dissolved nitrogen). Hysteresis in the C-Q relation was most pronounced for bio-cycled cations (K, Mg) and for Fe, which exhibited concentration during the first ascending limb followed by a chemostatic trend. A pulsed increase in Si concentration immediately after the first ascending limb in both flumes suggests mixing of deep groundwater with surface water. A continual increase in Ge/Si concentrations followed by a rapid decrease after the second rising limb may suggest a fast transition between soil water to ground water dominating the stream flow. Fourier transform infrared spectroscopy of selected samples across the hydrograph demonstrated pronounced changes in dissolved organic matter molecular composition with the advancement of the spring snow melt. X-ray micro-spectroscopy of colloidal material isolated from the collected water samples indicated a significant role for organic matter in the transport of inorganic colloids. Analyses of high

  8. The role of surface chemistry at ceramic/electrolyte intefaces in the generation of pulsed corona discharges in water using porous ceramic-coated rod electrodes

    Czech Academy of Sciences Publication Activity Database

    Lukeš, Petr; Člupek, Martin; Babický, Václav; Šunka, Pavel

    2009-01-01

    Roč. 6, č. 11 (2009), s. 719-728 ISSN 1612-8850 R&D Projects: GA AV ČR IAAX00430802 Institutional research plan: CEZ:AV0Z20430508 Keywords : non-thermal plasma * electrical discharge * water * surface chemistry Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 4.037, year: 2009 http://www3.interscience.wiley.com/cgi-bin/fulltext/122593644/PDFSTART

  9. Ecological effects of scrubber water discharge on coastal plankton: Potential synergistic effects of contaminants reduce survival and feeding of the copepod Acartia tonsa.

    Science.gov (United States)

    Koski, Marja; Stedmon, Colin; Trapp, Stefan

    2017-08-01

    To meet the oncoming requirements for lower sulphur emissions, shipping companies can install scrubbers where the exhaust is sprayed with seawater and subsequently discharged to the sea. The discharge water has a pH around 3 and contains elevated concentrations of vanadium, nickel, lead and hydrocarbons. We investigated 1) the threshold concentrations of scrubber discharge water for survival, feeding and reproduction of the copepod Acartia tonsa, 2) whether the effects depend on the exposure route and 3) whether exposure to discharge water can be detected in field-collected organisms. A direct exposure to discharge water increased adult copepod mortality and reduced feeding at metal concentrations which were orders of magnitude lower than the lethal concentrations in previous single-metal studies. In contrast, reproduction was not influenced by dietary uptake of contaminants. Scrubber water constituents could have synergistic effects on plankton productivity and bioaccumulation of metals, although the effects will depend on their dilution in the marine environment. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Groundwater discharge by evapotranspiration, flow of water in unsaturated soil, and stable isotope water sourcing in areas of sparse vegetation, Amargosa Desert, Nye County, Nevada

    Science.gov (United States)

    Moreo, Michael T.; Andraski, Brian J.; Garcia, C. Amanda

    2017-08-29

    This report documents methodology and results of a study to evaluate groundwater discharge by evapotranspiration (GWET) in sparsely vegetated areas of Amargosa Desert and improve understanding of hydrologic-continuum processes controlling groundwater discharge. Evapotranspiration and GWET rates were computed and characterized at three sites over 2 years using a combination of micrometeorological, unsaturated zone, and stable-isotope measurements. One site (Amargosa Flat Shallow [AFS]) was in a sparse and isolated area of saltgrass (Distichlis spicata) where the depth to groundwater was 3.8 meters (m). The second site (Amargosa Flat Deep [AFD]) was in a sparse cover of predominantly shadscale (Atriplex confertifolia) where the depth to groundwater was 5.3 m. The third site (Amargosa Desert Research Site [ADRS]), selected as a control site where GWET is assumed to be zero, was located in sparse vegetation dominated by creosote bush (Larrea tridentata) where the depth to groundwater was 110 m.Results indicated that capillary rise brought groundwater to within 0.9 m (at AFS) and 3 m (at AFD) of land surface, and that GWET rates were largely controlled by the slow but relatively persistent upward flow of water through the unsaturated zone in response to atmospheric-evaporative demands. Greater GWET at AFS (50 ± 20 millimeters per year [mm/yr]) than at AFD (16 ± 15 mm/yr) corresponded with its shallower depth to the capillary fringe and constantly higher soil-water content. The stable-isotope dataset for hydrogen (δ2H) and oxygen (δ18O) illustrated a broad range of plant-water-uptake scenarios. The AFS saltgrass and AFD shadscale responded to changing environmental conditions and their opportunistic water use included the time- and depth-variable uptake of unsaturated-zone water derived from a combination of groundwater and precipitation. These results can be used to estimate GWET in other areas of Amargosa Desert where hydrologic conditions are similar.

  11. Radium balance in discharge waters from coal mines in Poland the ecological impact of underground water treatment

    International Nuclear Information System (INIS)

    Chalupnik, S.; Wysocka, M.

    2008-01-01

    Saline waters from underground coal mines in Poland often contain natural radioactive isotopes, mainly 226 Ra from the uranium decay series and 228 Ra from the thorium series. More than 70% of the total amount of radium remains underground as radioactive deposits due to spontaneous co-precipitation or water treatment technologies, but several tens of MBq of 226 Ra and even higher activity of 228 Ra are released daily into the rivers along with the other mine effluents from all Polish coal mines. Mine waters can have a severe impact on the natural environment, mainly due to its salinity. Additionally high levels of radium concentration in river waters, bottom sediments and vegetation were also observed. Sometimes radium concentrations in rivers exceeded 0.7 kBq/m 3 , which was the permitted level for wastewaters under Polish law. The investigations described here were carried out for all coal mines and on this basis the total radium balance in effluents has been calculated. Measurements in the vicinity of mine settling ponds and in rivers have given an opportunity to study radium behaviour in river waters and to assess the degree of contamination. For removal of radium from saline waters a method of purification has been developed and implemented in full technical scale in two of Polish coal mines. The purification station in Piast Colliery was unique, the first underground installation for the removal of radium isotopes from saline waters. Very good results have been achieved - approximately 6 m 3 /min of radium-bearing waters were treated there, more than 100 MBq of 226 Ra and 228 Ra remained underground each day. Purification has been started in 1999, therefore a lot of experiences have been gathered during this period. Since year 2006, a new purification station is working in another colliery, Ziemowit, at the level -650 meters. Barium chloride is used as a cleaning , agent, and amount of water to be purified is reaching 9 m 3 /min. Technical measures such as

  12. Post-discharge evolution of reactive species in the water activated by a surface air plasma: a modeling study

    Science.gov (United States)

    Liu, Z. C.; Liu, D. X.; Chen, C.; Liu, Z. J.; Yang, A. J.; Rong, M. Z.; Chen, H. L.; Kong, M. G.

    2018-05-01

    Plasma-activated water (PAW) has been reported to sustain a bactericidal ability for months. However, many reactive species regarded as the main antibacterial agents in PAW have short lifetimes of less than one second. In order to explain the prolonged antibacterial ability of PAW and predict how to extend its effective time, we studied the post-discharge evolution of reactive species in PAW based on a system-level model reported previously. Three common storage conditions for PAW were considered within the post-discharge time of 14 d: (I) leaving the residual gas and PAW in the sealed reactor; (II) leaving PAW in the open air; (III) sealing the container of PAW. In comparison, storage condition III was the best condition to preserve the long-lived species including H2O2 and HNO2/, whereas storage condition I was the best method to preserve the short-lived species including OH, HO2 and ONOOH/ONOO‑. It suggests that the gas–liquid mass transfer plays an important role in the evolution of reactive species. We also found that O2NOOH/O2NOO‑ had an almost one order of magnitude higher concentration and a longer residue time than those of ONOOH/ONOO‑. This distinction suggests that the biological effect of O2NOOH/O2NOO‑ may be important.

  13. Charging and discharging characteristics of cool thermal energy storage system with horizontal pipes using water as phase change material

    International Nuclear Information System (INIS)

    Sait, H.H.; Selim, A.M.

    2014-01-01

    Highlights: • Ice is formed around horizontal tubes. • Optimum solid ice releasing is found. • Freezing and releasing of ice are controlled by ice resistance, time and tubes spacing. - Abstract: An experimental investigation of ice formation on cold vertical banks of horizontal tubes subjected to falling-film– jet mode– is conducted. In the charging process, a set of internally cooled vertical banks of horizontal tubes of brine is subjected to a falling film of water. The formed ice is periodically observed, photographed and measured in falling-film jet mode at specific internal coolant (ethylene–glycol solution) flow rates and temperatures. In the discharge process, the same solution is heated and used internally to release ice. Different thicknesses of the released ice are observed and measured. The maximum quantity of released ice is obtained and the optimum ice formation is determined. The results indicate that the ice formation and the solid ice released are controlled by the thermal resistance of the ice, time and pitch between tubes. The maximum gained ice has a thickness that is approximately equal to half of the tube spacing between the tubes utilized, which is formed in approximately 45 min and released in 12.5 min. The variation in heating solution temperature has a slight effect on the gained ice and discharging time

  14. Effects of uranium mining discharges on water quality in the Puerco River basin, Arizona and New Mexico

    Science.gov (United States)

    Van Metre, P.C.; Gray, J.R.

    1992-01-01

    From 1967 until 1986, uranium mine dewatering increased dissolved gross alpha, gross beta, uranium and radium activities and dissolved selenium and molybdenum concentrations in the Puerco River as indicated by time trends, areal patterns involving distance from the mines and stream discharge. Additionally, increased dissolved uranium concentrations were identified in groundwater under the Puerco River from where mine discharges entered the river to approximately the Arizona-New Mexico State line about 65 km downstream. Total mass of uranium and gross alpha activity released to the Puerco River by mine dewatering were estimated as 560 Mg (560 × 106 g) and 260 Ci, respectively. In comparison, a uranium mill tailings pond spill on 16 July 1979, released an estimated 1.5 Mg of uranium and 46 Ci of gross alpha activity. Mass balance calculations for alluvial ground water indicate that most of the uranium released did not remain in solution. Sorption of uranium on sediments and uptake of uranium by plants probably removed the uranium from solution.

  15. An inversion of the estuarine circulation by sluice water discharge and its impact on suspended sediment transport

    Science.gov (United States)

    Schulz, Kirstin; Gerkema, Theo

    2018-01-01

    The Wadden Sea is characterized by a complex topography of branching channels and intertidal flats, in which the interplay between fresh water discharges, wind forcing and the tidal current causes sediment transport rates and direction to be highly variable in space and time. During three field campaigns, indications of a negative estuarine circulation have been found in a channel adjacent to the coast in the Western Dutch Wadden Sea. Contrary to the classical picture of estuarine circulation, a periodic density stratification was observed that builds up during flood and breaks down during ebb. This can be related to a large freshwater source at the mouth of the channel, the sluice in Kornwerderzand. In this study, observations of this phenomenon are presented, and with the help of a numerical model the different drivers for residual suspended matter transport in this area, namely tidal asymmetries in the current velocity and the above mentioned periodic stratification, are investigated. It is found that the residual current in the area of interest points in ebb direction, caused by both the elongated ebb flow phase and the periodic stratification. On the contrary, the stronger flood currents cause a transport of suspended matter in flood direction. This transport is counteracted and therefore diminished by the effects of the sluice discharge.

  16. Quantification of leachate discharged to groundwater using the water balance method and the hydrologic evaluation of landfill performance (HELP) model.

    Science.gov (United States)

    Alslaibi, Tamer M; Abustan, Ismail; Mogheir, Yunes K; Afifi, Samir

    2013-01-01

    Landfills are a source of groundwater pollution in Gaza Strip. This study focused on Deir Al Balah landfill, which is a unique sanitary landfill site in Gaza Strip (i.e., it has a lining system and a leachate recirculation system). The objective of this article is to assess the generated leachate quantity and percolation to the groundwater aquifer at a specific site, using the approaches of (i) the hydrologic evaluation of landfill performance model (HELP) and (ii) the water balance method (WBM). The results show that when using the HELP model, the average volume of leachate discharged from Deir Al Balah landfill during the period 1997 to 2007 was around, 6800 m3/year. Meanwhile, the average volume of leachate percolated through the clay layer was 550 m3/year, which represents around 8% of the generated leachate. Meanwhile, the WBM indicated that the average volume of leachate discharged from Deir Al Balah landfill during the same period was around 7660 m3/year--about half of which comes from the moisture content of the waste, while the remainder comes from the infiltration of precipitation and re-circulated leachate. Therefore, the estimated quantity of leachate to groundwater by these two methods was very close. However, compared with the measured leachate quantity, these results were overestimated and indicated a dangerous threat to the groundwater aquifer, as there was no separation between municipal, hazardous and industrial wastes, in the area.

  17. Degradation of benzodiazepines using water falling film dielectric barrier discharge reactor

    Directory of Open Access Journals (Sweden)

    Radulović Vesna M.

    2017-01-01

    Full Text Available Classical methods of wastewater treatment are often not suitable for the treatment of pharmaceutical waste. The previous studies have shown that the use of the advanced oxidation procedures (AOP can lead to a more efficient degradation of various biologically active compounds, which are active pharmaceutical ingredients of applied drugs. The aim of this paper is the application of the plasma technology on the degradation of a two active pharmaceutical ingredients (APIs, diazepam and alprazolam and the finished products (Bensedin® and Ksalol® using the dielectric barrier discharge (DBD reactor for AOP. We studied the degradation rate of these pharmaceuticals, depending on the number of passes through the reactor. This degradation method was efficient 61 % for diazepam and 95 % alprazolam. We also examined the influence of the pH adjustment between the passes of APIs through the DBD reactor. The degradation rate of APIs and the finished products was monitored by the high performance liquid chromatography (HPLC technique, using a photodiode array detector. The concentration of the dissolved ozone was determined using the iodometric procedure. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. 172030

  18. The Plasma Discharge System For Effective Sterilization Of Water And Solid Surfaces

    International Nuclear Information System (INIS)

    Senturk, K.

    2010-01-01

    The different areas such as medicine, surgery, food production need efficient sterilization system since they are directly related to human health. In this work a new plasma system is described in order to present its effectiveness in sterilization. This is a different method from conventional methods such as: chemicals and heat addition, UV irradiation etc. The developed plasma system produces cold plasma working under atmospheric pressure. To generate the plasma both AC and DC high voltage power supplies were used. The developed system is cheap and very effective for sterilization. The light emission for both AC and DC coronas for the plasmas were investigated to understand the nature of generated plasma ionization. Different parameters like temperature, voltage, application time were changed during the plasma application and the optimization for killing the micro-organisms were investigated. To understand the biological effect of plasma on the organisms comparisons were done by using the scanning electron microscope and absorption spectrometer. The plasma was applied on the bacteria like Escherichia coli, Bacillus subtilis, Streptococcus mutans , the yeasts such as Candida albicans, and green algae. The efficiency, the non toxic nature, the affordable price make this plasma discharge method a very efficient one for sterilization.

  19. In vitro antifungal effect of mouth rinses containing chlorhexidine and thymol

    Directory of Open Access Journals (Sweden)

    Ashish Shrestha

    2011-03-01

    Conclusions: Antimicrobial agents used in the study had good in vitro activity against the two Candida species. Mouth rinses containing chlorhexidine showed superior antifungal and fungicidal activities compared to the thymol-containing mouth rinse. Both antimicrobial agents may be suggested for use as topical antifungal agents.

  20. Is carbohydrate mouth rinsing a novel approach to maintain exercise performance during Ramadan fasting?

    Directory of Open Access Journals (Sweden)

    Ahmad Munir Che Muhamed

    2014-12-01

    Full Text Available About a decade ago, carbohydrate mouth rinsing was shown to enhance endurance exercise performance. This improvement was more pronounced in a fasted compared to a fed state, suggesting that the ergogenic effect of carbohydrate mouth rinse is dependent on endogenous carbohydrate storage. Hence, indirectly highlights the potential use of carbohydrate mouth rinse as a potential strategy to mitigate the adverse effects of exercise during Ramadan fasting. To date, only one study has been carried out to explore the potential benefit of carbohydrate mouth rinse on exercise performance during Ramadan fasting. This single observation showed that a 10-km time trial performance was enhanced when performing mouth rinsing with either a carbohydrate or a placebo solution as compared with not performing mouth rinsing. While one study had acknowledged that the practice of mouth rinsing do have a positive effect on exercise performance during Ramadan fasting, future studies is warranted in order to have a better understanding on the underlying mechanisms associated with carbohydrate mouth rinsing during Ramadan fasting.

  1. Caffeine and 3-km cycling performance: Effects of mouth rinsing, genotype, and time of day.

    Science.gov (United States)

    Pataky, M W; Womack, C J; Saunders, M J; Goffe, J L; D'Lugos, A C; El-Sohemy, A; Luden, N D

    2016-06-01

    We assessed the efficacy of caffeine mouth rinsing on 3-km cycling performance and determined whether caffeine mouth rinsing affects performance gains influenced by the CYP1A2 polymorphism. Thirty-eight recreational cyclists completed four simulated 3-km time trials (TT). Subjects ingested either 6 mg/kg BW of caffeine or placebo 1 h prior to each TT. Additionally, 25 mL of 1.14% caffeine or placebo solution were mouth rinsed before each TT. The treatments were Placebo, caffeine Ingestion, caffeine Rinse and Ingestion+Rinse. Subjects were genotyped and classified as AA homozygotes or AC heterozygotes for the rs762551 polymorphism of the CYP1A2 gene involved in caffeine metabolism. Magnitude-based inferences were used to evaluate treatment differences in mean power output based on a predetermined meaningful treatment effect of 1.0%. AC heterozygotes (4.1%) and AA homozygotes (3.4%) benefited from Ingestion+Rinse, but only AC performed better with Ingestion (6.0%). Additionally, Rinse and Ingestion+Rinse elicited better performance relative to Placebo among subjects that performed prior to 10:00 h (Early) compared with after 10:00 h (Late). The present study provides additional evidence of genotype and time of day factors that affect the ergogenic value of caffeine intake that may allow for more personalized caffeine intake strategies to maximize performance. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  2. 77 FR 11401 - Marine Sanitation Devices (MSDs): No Discharge Zone (NDZ) for California State Marine Waters

    Science.gov (United States)

    2012-02-27

    ..., recreational, conservation, research, educational, and aesthetic values, and are becoming increasingly more... sewage; and (2) it will improve California marine waters for commercial fisheries, tourism, aesthetics...-out facilities, educational outreach, and establishment of small NDZs under CWA Section 312(f)(3) in...

  3. Measuring water and sediment discharge from a road plot with a settling basin and tipping bucket

    Science.gov (United States)

    Thomas A. Black; Charles H. Luce

    2013-01-01

    A simple empirical method quantifies water and sediment production from a forest road surface, and is well suited for calibration and validation of road sediment models. To apply this quantitative method, the hydrologic technician installs bordered plots on existing typical road segments and measures coarse sediment production in a settling tank. When a tipping bucket...

  4. Radioecological aspects of the discharge of radioactive substances with waste water and exhaust air

    International Nuclear Information System (INIS)

    Bachner, D.; Becker, A.; Biesold, H.

    1976-01-01

    Radioecological aspects concerning radioactive effluents via air and water are under discussion. The essential patterns are defined and two food-chains (green vegetables-man, fish-man) will be taken here as an example for a look at the main parameters. Under typical emission conditions the environmental impacts for various pathways are given. (orig.) [de

  5. Carbohydrate mouth rinse: does it improve endurance exercise performance?

    Directory of Open Access Journals (Sweden)

    Painelli Vitor

    2010-08-01

    Full Text Available Abstract It is well known that carbohydrate (CHO supplementation can improve performance in endurance exercises through several mechanisms such as maintenance of glycemia and sparing endogenous glycogen as well as the possibility of a central nervous-system action. Some studies have emerged in recent years in order to test the hypothesis of ergogenic action via central nervous system. Recent studies have demonstrated that CHO mouth rinse can lead to improved performance of cyclists, and this may be associated with the activation of brain areas linked to motivation and reward. These findings have already been replicated in other endurance modalities, such as running. This alternative seems to be an attractive nutritional tool to improve endurance exercise performance.

  6. Probabilistic Prognosis of Environmental Radioactivity Concentrations due to Radioisotopes Discharged to Water Bodies from Nuclear Power Plants.

    Science.gov (United States)

    Tomás Zerquera, Juan; Mora, Juan C; Robles, Beatriz

    2017-11-15

    Due to their very low values, the complexity of comparing the contribution of nuclear power plants (NPPs) to environmental radioactivity with modeled values is recognized. In order to compare probabilistic prognosis of radioactivity concentrations with environmental measurement values, an exercise was performed using public data of radioactive routine discharges from three representative Spanish nuclear power plants. Specifically, data on liquid discharges from three Spanish NPPs: Almaraz, Vandellós II, and Ascó to three different aquatic bodies (river, lake, and coast) were used. Results modelled using generic conservative models together with Monte Carlo techniques used for uncertainties propagation were compared with values of radioactivity concentrations in the environment measured in the surroundings of these NPPs. Probability distribution functions were inferred for the source term, used as an input to the model to estimate the radioactivity concentrations in the environment due to discharges to the water bodies. Radioactivity concentrations measured in bottom sediments were used in the exercise due to their accumulation properties. Of all the radioisotopes measured in the environmental monitoring programs around the NPPs, only Cs-137, Sr-90, and Co-60 had positive values greater than their respective detection limits. Of those, Sr-90 and Cs-137 are easily measured in the environment, but significant contribution from the radioactive fall-out due to nuclear explosions in the atmosphere exists, and therefore their values cannot be attributed to the NPPs. On the contrary, Co-60 is especially useful as an indicator of the radioactive discharges from NPPs because its presence in the environment can solely be attributed to the impact of the closer nuclear facilities. All the modelled values for Co-60 showed a reasonable correspondence with measured environmental data in all cases, being conservative in two of them. The more conservative predictions obtained with

  7. THE STRUCTURE OF THE WATER CONSTRUCTIONS IN THE SEBES HYDROGRAPHIC BASIN AND THE STORAGE RESERVOIRS. EFFECT ON THE AVERAGE DISCHARGE

    Directory of Open Access Journals (Sweden)

    Stef Iulian Ioan

    2013-05-01

    Full Text Available In the upper basin of the Sebes Valley, the oldest storage lakes have been temporary artificial lakes, called haituri in Romanian. They were created within the forest exploitation areas. Inside the dams of those retention lakes, which dams are made of a wooden skeleton, filled with soil and stones, there have been weirs for the quick discharge of the water, having the purpose of creating some flood trends, capable of carrying over the logs, downstream the lake. At present, some of those temporary artificial lakes are used as trout farms, while others are damaged, or operate as basins for the sedimentation of the alluvial deposits. The difference of level between the springs of the Sebes and the Mures Rivers generates a convertible hydroelectric potential, having an average power exceeding 60,000 kW" />

  8. Effect of Shock Waves Generated by Pulsed Electric Discharges in Water on Yeast Cells and Virus Particles

    Science.gov (United States)

    Girdyuk, A. E.; Gorshkov, A. N.; Egorov, V. V.; Kolikov, V. A.; Snetov, V. N.; Shneerson, G. A.

    2018-02-01

    The aim of this study is to determine the optimal parameters of the electric pulses and shock waves generated by them for the soft destruction of the virus and yeast envelopes with no changes in the structure of antigenic surface albumin and in the cell morphology in order to use them to produce antivirus vaccines and in biotechnology. The pulse electric discharges in water have been studied for different values of amplitude, pulse duration and the rate of the rise in the current. A mathematical model has been developed to estimate the optimal parameters of pulsed electric charges and shock waves for the complete destruction of the yeast cell envelopes and virus particles at a minimum of pulses.

  9. Management and construction of a major zero discharge water supply and treatment scheme at Mount Piper Power Station, Australia

    Energy Technology Data Exchange (ETDEWEB)

    Wong, P.; Docker, P.; Gabbrielli, E.; Wade, P. [Pacific Power, Sydney, NSW (Australia)

    1994-09-01

    Excellence in the organisation and management of a large multi-disciplinary design and construct project such as the zero discharge water supply and treatment scheme for Mount Piper coal-fired power station was essential to its successful execution. This paper discusses the management philosophies and strategies of Pacific Power and Transfield-PWT Asia/Pacific that resulted in this project being completed to the satisfaction of the client in the minimum time without delays and cost increases caused by interfaces between the parties. It highlights the advantages of contract packaging and placing the total responsibility for the performance and integration of a complex project system on one organisation. 2 refs., 6 figs.

  10. INFLUENCE OF SHOCK VOLTAGE FROM THE ELECTRIC DISCHARGE ON THE FATIGUE ENDURANCE OF CARBON STEEL IN WATER

    Directory of Open Access Journals (Sweden)

    I. O. Vakulenko

    2015-09-01

    Full Text Available Purpose. The research supposes the explanation of influence of stress impulses from an electrical discharge in water on the level of the limited endurance at a cyclic loading of the thermally work-hardened carbon steel. Methodology. Material for research was steel 45 (0,45 % carbon with сoncentration of chemical elements within the limits of steel composition. Specimens for tests are made as plates in 1 thick, width 15 and length 120-180 mm. The structural state of steel corresponded to quenching on a martensite from the normal temperatures of annealing and tempering at 300C, duration of 1 h. Microstructure was investigated with the use of electronic microscopy, the density of dislocations was estimated on the methods of X-ray analysis. Hardness was measured on the method of Rockwell (scale of «C». A cyclic loading was carried out in the conditions of symmetric bend on a tester «Saturn-10» at a temperature +20C. The treatment by shock voltage from the electrical discharge was carried out in water on setting of bath type «Iskra-23», used for cleaning of castings manufactures. Electric impulses were formed at 15-18 kV with energy of 10-12 kJ and amplitude of 1-2 GPа. Findings. As a result of processing pulses of a pressure wave of heat-strengthened steel 45 found the increase of endurance under the cyclic loading corresponds to an increased amount of accumulated dislocations on the fracture surface. The use of Coffin–Manson Equation allowed finding the decrease of deformation per cycle of loading as a result of arising stress from an electrical discharge in water. On the fracture surface (after pulse exposure was found the increased number of dislocations, located in different crystallographic systems, that is a testament to the rather complicated development of dislocation transformations in the structure of steel, which provide an increase of endurance at a fatigue. The increase of the limited endurance became as a result of impulsive

  11. Synergistic effect of plasmacatalyst and ozone in a pulsed corona discharge reactor on the decomposition of organic pollutants in water

    Energy Technology Data Exchange (ETDEWEB)

    Malik, Muhammad Arif [Applied Chemistry Laboratories, PINSTECH, PO Nilore, Islamabad (Pakistan)

    2003-11-01

    Plasmacatalytic effects of {alpha}-alumina, {gamma}-alumina, and silica gel in a pulsed corona discharge (PCD) reactor on the decomposition of aqueous methylene blue are described. Methylene blue concentration in the effluent was reduced to 23% of the inlet concentration by PCDs in water. Under the same experimental conditions, addition of {alpha}-alumina further reduced it to 8%, {gamma}-alumina to 4%, and silica gel to below the detection limits. PCDs with silica gel were run for >100 h in a continuous flow reactor and methylene blue in the effluent remained below the detection limit. A hybrid system of plasmacatalysis and ozonation is also described. Phenol concentration in the effluent was reduced to 84% of the inlet concentration by PCDs in water. Under the same experimental conditions, addition of either silica gel or ozone further reduced it to around 35%, and simultaneous addition of silica gel and ozone to 14% of inlet concentration. Decolourization of pre-adsorbed methylene blue on silica gel has been demonstrated. Adsorption and stabilization of the chemically active species on silica gel was indicated by experimental evidence. A significant improvement in the rate of decomposition of organic pollutants in water has been realized by hybridizing plasmacatalysis and ozonation in a PCD reactor.

  12. Synergistic effect of plasmacatalyst and ozone in a pulsed corona discharge reactor on the decomposition of organic pollutants in water

    International Nuclear Information System (INIS)

    Malik, Muhammad Arif

    2003-01-01

    Plasmacatalytic effects of α-alumina, γ-alumina, and silica gel in a pulsed corona discharge (PCD) reactor on the decomposition of aqueous methylene blue are described. Methylene blue concentration in the effluent was reduced to 23% of the inlet concentration by PCDs in water. Under the same experimental conditions, addition of α-alumina further reduced it to 8%, γ-alumina to 4%, and silica gel to below the detection limits. PCDs with silica gel were run for >100 h in a continuous flow reactor and methylene blue in the effluent remained below the detection limit. A hybrid system of plasmacatalysis and ozonation is also described. Phenol concentration in the effluent was reduced to 84% of the inlet concentration by PCDs in water. Under the same experimental conditions, addition of either silica gel or ozone further reduced it to around 35%, and simultaneous addition of silica gel and ozone to 14% of inlet concentration. Decolourization of pre-adsorbed methylene blue on silica gel has been demonstrated. Adsorption and stabilization of the chemically active species on silica gel was indicated by experimental evidence. A significant improvement in the rate of decomposition of organic pollutants in water has been realized by hybridizing plasmacatalysis and ozonation in a PCD reactor

  13. Quantity and quality of ground-water discharge to the South Platte River, Denver to Fort Lupton, Colorado, August 1992 through July 1993

    Science.gov (United States)

    McMahon, P.B.; Lull, K.J.; Dennehy, K.F.; Collins, J.A.

    1995-01-01

    Water-quality studies conducted by the Metro Wastewater Reclamation District have indicated that during low flow in segments of the South Platte River between Denver and Fort Lupton, concentrations of dissolved oxygen are less than minimum concen- trations set by the State of Colorado. Low dissolved-oxygen concentrations are observed in two reaches of the river-they are about 3.3 to 6.4 miles and 17 to 25 miles downstream from the Metro Waste- water Reclamation District effluent outfalls. Concentrations of dissolved oxygen recover between these two reaches. Studies conducted by the U.S. Geological Survey have indicated that ground-water discharge to the river may contribute to these low dissolved-oxygen concentrations. As a result, an assessment was made of the quantity and quality of ground-water discharge to the South Platte River from Denver to Fort Lupton. Measurements of surface- water and ground-water discharge and collections of surface water and ground water for water-quality analyses were made from August 1992 through January 1993 and in May and July 1993. The quantity of ground-water discharge to the South Platte River was determined indirectly by mass balance of surface-water inflows and outflows and directly by instantaneous measurements of ground-water discharge across the sediment/water interface in the river channel. The quality of surface water and ground water was determined by sampling and analysis of water from the river and monitoring wells screened in the alluvial aquifer adjacent to the river and by sampling and analysis of water from piezometers screened in sediments underlying the river channel. The ground-water flow system was subdivided into a large-area and a small-area flow system. The precise boundaries of the two flow systems are not known. However, the large-area flow system is considered to incorporate all alluvial sediments in hydrologic connection with the South Platte River. The small- area flow system is considered to incorporate

  14. Custom design of a hanging cooling water power generating system applied to a sensitive cooling water discharge weir in a seaside power plant: A challenging energy scheme

    International Nuclear Information System (INIS)

    Tian, Chuan Min; Jaffar, Mohd Narzam; Ramji, Harunal Rejan; Abdullah, Mohammad Omar

    2015-01-01

    In this study, an innovative design of hydro-electricity system was applied to an unconventional site in an attempt to generate electricity from the exhaust cooling water of a coal-fired power plant. Inspired by the idea of micro hydro, present study can be considered new in three aspects: design, resource and site. This system was hung at a cooling water discharge weir, where all sorts of civil work were prohibited and sea water was used as the cooling water. It was designed and fabricated in the university's mechanical workshop and transported to the site for installation. The system was then put into proof run for a three-month period and achieved some success. Due to safety reasons, on-site testing was prohibited by the power plant authority. Hence, most data was acquired from the proof run. The driving system efficiency was tested in the range of 25% and 45% experimentally while modeling results came close to experimental results. Payback period for the system is estimated to be about 4.23 years. Result obtained validates the feasibility of the overall design under the sensitive site application. - Highlights: • Challenging energy scheme via a hanging cooling water power generating system. • Driving system efficiency was tested in the range of 25% and 45%. • Payback period for the system is estimated to be about 4.2 years

  15. 77 FR 17253 - Standards for Living Organisms in Ships' Ballast Water Discharged in U.S. Waters

    Science.gov (United States)

    2012-03-23

    ... meant ``best available technology'' as a term of art under the Clean Water Act or merely the best... Guard is also amending its regulations for engineering equipment by establishing an approval process for.... Unfunded Mandates Reform Act G. Taking of Private Property H. Civil Justice Reform I. Protection of...

  16. Nipple Discharge

    Science.gov (United States)

    ... any unexpected nipple discharge evaluated by a doctor. Nipple discharge in men under any circumstances could be a problem and needs further evaluation. One or both breasts may produce a nipple discharge, either spontaneously or when you squeeze your ...

  17. Recharge Area, Base-Flow and Quick-Flow Discharge Rates and Ages, and General Water Quality of Big Spring in Carter County, Missouri, 2000-04

    Science.gov (United States)

    Imes, Jeffrey L.; Plummer, Niel; Kleeschulte, Michael J.; Schumacher, John G.

    2007-01-01

    Exploration for lead deposits has occurred in a mature karst area of southeast Missouri that is highly valued for its scenic beauty and recreational opportunities. The area contains the two largest springs in Missouri (Big Spring and Greer Spring), both of which flow into federally designated scenic rivers. Concerns about potential mining effects on the area ground water and aquatic biota prompted an investigation of Big Spring. Water-level measurements made during 2000 helped define the recharge area of Big Spring, Greer Spring, Mammoth Spring, and Boze Mill Spring. The data infer two distinct potentiometric surfaces. The shallow potentiometric surface, where the depth-to-water is less than about 250 feet, tends to mimic topographic features and is strongly controlled by streams. The deep potentiometric surface, where the depth-to-water is greater than about 250 feet represents ground-water hydraulic heads within the more mature karst areas. A highly permeable zone extends about 20 mile west of Big Spring toward the upper Hurricane Creek Basin. Deeper flowing water in the Big Spring recharge area is directed toward this permeable zone. The estimated sizes of the spring recharge areas are 426 square miles for Big Spring, 352 square miles for Greer Spring, 290 square miles for Mammoth Spring, and 54 square miles for Boze Mill Spring. A discharge accumulation curve using Big Spring daily mean