WorldWideScience

Sample records for air contaminants combining

  1. Performance of personalized ventilation combined with chilled ceiling in an office room: inhaled air quality and contaminant distribution

    DEFF Research Database (Denmark)

    Lipczynska, Aleksandra; Kaczmarczyk, Jan; Melikov, Arsen Krikor

    2014-01-01

    In a simulated two persons’ office room inhaled air quality and contaminant distribution provided with personalized ventilation combined with chilled ceiling, mixing ventilation only, chilled ceiling with mixing ventilation and chilled ceiling with mixing and personalized ventilation was studied...... people (exhaled air, bioeffluents) and building materials (wall painting). Personalized ventilation combined with chilled ceiling ensured highest air quality at the workstation under all conditions. Pollutant concentration in the occupied zone away from the workstations did not differ substantially...... between the tested systems. Chilled ceiling combined with personalized ventilation working as the only air supplying system may be optimal solution in many buildings....

  2. Advanced air distribution method combined with deodorant material for exposure reduction to bioeffluents contaminants in hospitals

    DEFF Research Database (Denmark)

    Bivolarova, Mariya Petrova; Mizutani, Chiyomi; Melikov, Arsen Krikor;

    2015-01-01

    The separate and combined effect of a ventilated mattress and acid-treated activated carbon fibre (ACF) fabric on reducing the exposure to body generated gaseous pollutants in hospital environment was studied. Full-scale experiments were performed in a climate chamber furnished as a single......-bed hospital patient room at reduced background ventilation rare of 1.6 air changes per hour. The bed of the patient was equipped with the ventilated mattress (VM) having an exhaust opening from which bioeffluents generated from human body were sucked and discharged from the room. To enhance the pollutant...

  3. Control of aerosol contaminants in indoor air: combining the particle concentration reduction with microbial inactivation.

    Science.gov (United States)

    Grinshpun, Sergey A; Adhikari, Atin; Honda, Takeshi; Kim, Ki Youn; Toivola, Mika; Rao, K S Ramchander; Reponen, Tiina

    2007-01-15

    An indoor air purification technique, which combines unipolar ion emission and photocatalytic oxidation (promoted by a specially designed RCI cell), was investigated in two test chambers, 2.75 m3 and 24.3 m3, using nonbiological and biological challenge aerosols. The reduction in particle concentration was measured size selectively in real-time, and the Air Cleaning Factor and the Clean Air Delivery Rate (CADR) were determined. While testing with virions and bacteria, bioaerosol samples were collected and analyzed, and the microorganism survival rate was determined as a function of exposure time. We observed that the aerosol concentration decreased approximately 10 to approximately 100 times more rapidly when the purifier operated as compared to the natural decay. The data suggest that the tested portable unit operating in approximately 25 m3 non-ventilated room is capable to provide CADR-values more than twice as great than the conventional closed-loop HVAC system with a rating 8 filter. The particle removal occurred due to unipolar ion emission, while the inactivation of viable airborne microorganisms was associated with photocatalytic oxidation. Approximately 90% of initially viable MS2 viruses were inactivated resulting from 10 to 60 min exposure to the photocatalytic oxidation. Approximately 75% of viable B. subtilis spores were inactivated in 10 min, and about 90% or greater after 30 min. The biological and chemical mechanisms that led to the inactivation of stress-resistant airborne viruses and bacterial spores were reviewed. PMID:17310729

  4. Bioaccumulation Potential Of Air Contaminants: Combining Biological Allometry, Chemical Equilibrium And Mass-Balances To Predict Accumulation Of Air Pollutants In Various Mammals

    Energy Technology Data Exchange (ETDEWEB)

    Veltman, Karin; McKone, Thomas E.; Huijbregts, Mark A.J.; Hendriks, A. Jan

    2009-03-01

    In the present study we develop and test a uniform model intended for single compartment analysis in the context of human and environmental risk assessment of airborne contaminants. The new aspects of the model are the integration of biological allometry with fugacity-based mass-balance theory to describe exchange of contaminants with air. The developed model is applicable to various mammalian species and a range of chemicals, while requiring few and typically well-known input parameters, such as the adult mass and composition of the species, and the octanol-water and air-water partition coefficient of the chemical. Accumulation of organic chemicals is typically considered to be a function of the chemical affinity forlipid components in tissues. Here, we use a generic description of chemical affinity for neutral and polar lipids and proteins to estimate blood-air partition coefficients (Kba) and tissue-air partition coefficients (Kta) for various mammals. This provides a more accurate prediction of blood-air partition coefficients, as proteins make up a large fraction of total blood components. The results show that 75percent of the modeled inhalation and exhalation rate constants are within a factor of 2 from independent empirical values for humans, rats and mice, and 87percent of the predicted blood-air partition coefficients are within a factor of 5 from empirical data. At steady-state, the bioaccumulation potential of air pollutants is shown to be mainly a function of the tissue-air partition coefficient and the biotransformation capacity of the species and depends weakly on the ventilation rate and the cardiac output of mammals.

  5. Combined in-situ and ex-situ bioremediation of petroleum hydrocarbon contaminated soils by closed-loop soil vapor extraction and air injection

    International Nuclear Information System (INIS)

    Treatment and restoration of petroleum hydrocarbon contaminated soils at a bulk petroleum above-ground storage tank (AST) site in Michigan is being conducted through in-situ and ex-situ closed-loop soil vapor extraction (SVE), soil vapor treatment, and treated air injection (AI) processes. The soil vapor extraction process applies a vacuum through the petroleum hydrocarbon affected soils in the ex-situ bio-remediation pile (bio-pile) and along the perimeter of excavated area (in-situ area) to remove the volatile or light petroleum hydrocarbons. This process also draws ambient air into the ex-situ bio-pile and in-situ vadose zone soil along the perimeter of excavated area to enhance biodegradation of light and heavy petroleum hydrocarbons in the soil. The extracted soil vapor is treated using a custom-designed air bio-remediation filter (bio-filter) to degrade the petroleum hydrocarbon compounds in the soil vapor extraction air streams. The treated air is then injected into a flush grade soil bed in the backfill area to perform final polishing of the air stream, and to form a closed-loop air flow with the soil vapor extraction perforated pipes along the perimeter of the excavated area

  6. Air Contamination With Fungals In Museum

    Science.gov (United States)

    Scarlat, Iuliana; Haiducu, Maria; Stepa, Raluca

    2015-07-01

    The aim of the studies was to determine the level and kind of fungal contamination of air in museum, deposits patrimony, restoration and conservation laboratories and their effects on health of workers. Microbiological air purity was measured with a SAS-100 Surface Air System impactor. The fungal contamination was observed in all 54 rooms where we made determinations. The highest levels of fungal were recorded at rooms with hygroscopic patrimony objects, eg carpets, chairs, upholstered chairs, books etc. The most species identified included under common allergens: Aspergillus, Penicillium, and Mucor. There fungal species belonging to the genus identified in this study, can trigger serious diseases museum workers, such as for example Aspergillus fumigatus, known allergies and toxic effects that may occur. In some places of the museum, occupational exposure limit values to fungi present in the air in the work environment, recommended by the specialized literature, have been overcome.

  7. An Air-Stripping Packed Bed Combined with a Biofilm-Type Biological Process for Treating BTEX and Total Petroleum Hydrocarbon Contaminated Groudwater

    Science.gov (United States)

    Hong, U.; Park, S.; Lim, J.; Lee, W.; Kwon, S.; Kim, Y.

    2009-12-01

    In this study, we examined the removal efficiency of a volatile compound (e.g. toluene) and a less volatile compound [e.g. total petroleum hydrocarbon (TPH)] using an air stripping packed bed combined with a biofilm-type biological process. We hypothesized that this system might be effective and economical to simultaneously remove both volatile and less volatile compounds. The gas-tight reactor has 5.9-inch-diameter and 48.8-inch-height. A spray nozzle was installed at the top cover to distribute the liquid evenly through reactor. The reactor was filled with polypropylene packing media for the increase of volatilization surface area and the growth of TPH degrading facultative aerobic bacteria on the surface of the packing media. In air stripping experiments, 45.6%, 71.7%, 72.0%, and 75.4% of toluene was removed at air injection rates of 0 L/min, 2.5 L/min, 4 L/min, and 6 L/min, respectively. Through the result, we confirmed that toluene removal efficiency increased by injecting higher amounts of air. TPH removal by stripping was minimal. To remove a less volatile TPH by commercial TPH degrading culture (BIO-ZYME B-52), 15-times diluted culture was circulated through the reactor for 2-3 days to build up a biofilm on the surface of packing media with 1 mg-soluble nitrogen source /L-water per 1 ppm of TPH. Experiments evaluating the degree of TPH biodegradation in this system are carrying out.

  8. Fungi as contaminants in indoor air

    Science.gov (United States)

    Miller, J. David

    This article reviews the subject of contamination of indoor air with fungal spores. In the last few years there have been advances in several areas of research on this subject. A number of epidemiological studies have been conducted in the U.K., U.S.A. and Canada. These suggest that exposure to dampness and mold in homes is a significant risk factor for a number of respiratory symptoms. Well-known illnesses caused by fungi include allergy and hypersensitivity pneumonitis. There is now evidence that other consequences of exposure to spores of some fungi may be important. In particular, exposure to low molecular weight compounds retained in spores of some molds such as mycotoxins and β 1,3 glucans appears to contribute to some symptoms reported. Fungal contamination of building air is almost always caused by poor design and/or maintenance. Home owners and building operators need to take evidence of fungal contamination seriously.

  9. Air contaminants in a submarine equipped with air independent propulsion.

    Science.gov (United States)

    Persson, Ola; Ostberg, Christina; Pagels, Joakim; Sebastian, Aleksandra

    2006-11-01

    The Swedish Navy has operated submarines equipped with air independent propulsion for two decades. This type of submarine can stay submerged for periods far longer than other non-nuclear submarines are capable of. The air quality during longer periods of submersion has so far not been thoroughly investigated. This study presents results for a number of air quality parameters obtained during more than one week of continuous submerged operation. The measured parameters are pressure, temperature, relative humidity, oxygen, carbon dioxide, hydrogen, formaldehyde and other volatile organic compounds, ozone, nitrogen dioxide, particulate matter and microbiological contaminants. The measurements of airborne particles demonstrate that air pollutants typically occur at a low baseline level due to high air exchange rates and efficient air-cleaning devices. However, short-lived peaks with comparatively high concentrations occur, several of the sources for these have been identified. The concentrations of the pollutants measured in this study do not indicate a build-up of hazardous compounds during eight days of submersion. It is reasonable to assume that a substantial build-up of the investigated contaminants is not likely if the submersion period is prolonged several times, which is the case for modern submarines equipped with air independent propulsion. PMID:17075617

  10. Air cleaning issues with contaminated sites

    Energy Technology Data Exchange (ETDEWEB)

    Bellamy, R.R. [Nuclear Regulatory Commission, King of Prussia, PA (United States)

    1997-08-01

    The US Nuclear Regulatory Commission has developed a list of contaminated sites that warrant special USNRC attention because they pose unique or complex decommissioning issues. This list of radiologically contaminated sites is termed the Site Decommissioning Management Plan (SDMP), and was first issued in 1990. A site is placed on the SDMP list if it has; (1) Problems with the viability of the responsible organization (e.g., the licensee for the site is unable or unwilling to pay for the decommissioning); (2) Large amounts of soil contamination or unused settling ponds or burial grounds that may make the waste difficult to dispose of; (3) The long-term presence of contaminated, unused buildings; (4) A previously terminated license; or (5) Contaminated or potential contamination of the ground water from on-site wastes. In deciding whether to add a site to the SDMP list, the NRC also considers the projected length of time for decommissioning and the willingness of the responsible organization to complete the decommissioning in a timely manner. Since the list was established, 9 sites have been removed from the list, and the current SDMP list contains 47 sites in 11 states. The USNRC annually publishes NUREG-1444, {open_quotes}Site Decommissioning Management Plan{close_quotes}, which updates the status of each site. This paper will discuss the philosophical goals of the SDMP, then will concentrate on the regulatory requirements associated with air cleaning issues at the SDMP sites during characterization and remediation. Both effluent and worker protection issues will be discussed. For effluents, the source terms at sites will be characterized, and measurement techniques will be presented. Off-site dose impacts will be included. For worker protection issues, air sampling analyses will be presented in order to show how the workers are adequately protected and their doses measured to satisfy regulatory criteria during decontamination operations. 1 tab.

  11. Radioactive aerosol air contamination monitor (MAFF)

    International Nuclear Information System (INIS)

    The MAFF is a highly sensitive monitor designed to measure and signal accidental air contamination at values well below those generally detectable, allowing for high-amplitude variations due to radon daughter products. It consists of a standard electronic rack, which has been designed for use under highly varied conditions: detection of α, β, X radiation, number of independent channels (from 1 to 4), internal or external sunction pump, internal or external threshold processing, on-line computer or self-contained operation. Air is drawn in continuously through a stationary filter paper by a single pump. Each channel includes a scintillation detector and photomultiplier, and delivers an output signal proportional to the activity of the radionuclides trapped by the filter. The single-channel version is equipped with an oversize scintillator and photomultiplier with very high sensitivity. The electronic equipment consists of plug-in units which are selected according to each configuration. The control and display section includes a large number of safety systems which guarantee high equipment operating reliability. The MAFF is currently used in several reactors and hot laboratories

  12. Mold contamination and air handling units.

    Science.gov (United States)

    Wilson, Stephen C; Palmatier, Robert N; Andriychuk, Larysa A; Martin, Jared M; Jumper, Cynthia A; Holder, Homer W; Straus, David C

    2007-07-01

    An investigation was conducted on selected locations in air handling units (AHUs) to (a) identify common mold species found on these locations, (b) determine whether some locations (and subsets) featured mold growth sites more frequently than others, (c) ascertain whether the operating condition of AHUs is related to mold contamination, and (d) provide a basis for a microbial sampling protocol for AHUs. A total of 566 tape lifts and 570 swab samples were collected from the blower wheel fan blades, insulation, cooling coil fins, and ductwork from 25 AHUs. All AHU conditions were numerically rated using a heating, ventilation and air-conditioning (HVAC) survey. Results showed that Cladosporium sp. fungi were commonly recovered in terms of growth sites and deposited spores, and they were found mainly in the blower wheel fan blades, the ductwork, and the cooling coil fins. Subsections of the fan blades, insulation, and cooling coil fins showed no preferred area for mold growth sites. Other organisms such as Penicillium sp., Aspergillus sp., and Paecilomyces sp. were recovered from the cooling coil fins and insulation. Because of the widespread prevalence of Cladosporium sp., there was no relationship between mold growth and operating condition. However, the presence of different species of molds in locations other than the blower wheel blades may indicate that the AHU condition is not optimal. A suggested microbial sampling protocol including interpretations of sample results is presented. PMID:17487721

  13. 29 CFR 1910.19 - Special provisions for air contaminants.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 5 2010-07-01 2010-07-01 false Special provisions for air contaminants. 1910.19 Section 1910.19 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION... Standards § 1910.19 Special provisions for air contaminants. (a) Asbestos, tremolite, anthophyllite,...

  14. Trace Contaminant Monitor for Air in Spacecraft Project

    Data.gov (United States)

    National Aeronautics and Space Administration — A need exists for analyzers that can measure trace contaminants in air on board spacecraft. Toxic gas buildup can endanger the crew particularly during long...

  15. Micro GC's for Contaminant Monitoring in Spacecraft Air Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The objective of this proposal is to create new gas chromatographs (GCs) for contaminant monitoring in spacecraft air that do not require any reagents or special...

  16. Comparison of indoor air and outdoor air contaminant concentrations

    OpenAIRE

    Pykhova, Ekaterina

    2014-01-01

    Since most people spend their time indoors, there has been increased interest in air pollution concen-trations. Number of very small liquid and solid particles suspended in the air is depending on different factors. But how should be decreased particle number? The field of this work is particulate matter concentration in the indoor and outdoor air. Measurements were carried out in number concentration. The Indoor-Outdoor correlation was de-termined in order to investigate normative parti...

  17. 29 CFR 1910.1000 - Air contaminants.

    Science.gov (United States)

    2010-07-01

    ... contaminant. L is the exposure limit for that substance specified in subpart Z of 29 CFR part 1910. The value... in subpart Z of 29 CFR part 1910 in order to determine whether an employee is exposed over the... weighted average specified in subpart Z of 29 CFR part 1910 for the substance involved. (ii) To...

  18. 29 CFR 1915.1000 - Air contaminants.

    Science.gov (United States)

    2010-07-01

    ... particular contaminant. L is the exposure limit for that substance specified in subpart Z of 29 CFR part 1915... subpart Z of 29 CFR part 1915 in order to determine whether an employee is exposed over the regulatory... average specified in subpart Z of 29 CFR part 1915 for the material involved. (ii) To illustrate...

  19. Effect of air-conditioner on fungal contamination

    Science.gov (United States)

    Hamada, Nobuo; Fujita, Tadao

    Air-conditioners (AC) produce much dew and wet conditions inside their apparatus, when in operation. We studied the fungal contamination in AC and found that the average fungal contamination of AC filters was about 5-fold greater than that of a carpet, and Cladosporium and Penicillium were predominant in AC filters. The fungal contamination inside AC, which were used everyday, increased more markedly than those not used daily, e.g. a few days per week or rarely. Moreover, the airborne fungal contamination in rooms during air-conditioning was about 2-fold greater than one in rooms without AC, and was highest when air-conditioning started and decreased gradually with time. We recognized that the airborne fungal contamination was controlled by the environmental condition of the rooms, in which AC were used. It is suggested that AC might promote mold allergies in users via airborne fungal spores derived from the AC. On the other hand, AC was estimated to remove moisture in the room atmosphere and carpets, and reduce the relative humidity in rooms. It was found that the average fungal contamination in the house dust of carpets with AC was suppressed by two-third of that in rooms without AC. The use of AC for suppressing fungal hazards was discussed.

  20. Combined air and water pollution control system

    Science.gov (United States)

    Wolverton, Billy C. (Inventor); Jarrell, Lamont (Inventor)

    1990-01-01

    A bioaquatic air pollution control system for controlling both water and atmospheric pollution is disclosed. The pollution control system includes an exhaust for directing polluted gases out of a furnace and a fluid circulating system which circulates fluid, such as waste water, from a source, past the furnace where the fluid flow entrains the pollutants from the furnace. The combined fluid and pollutants are then directed through a rock/plant/microbial filtering system. A suction pump pumps the treated waste water from the filter system past the exhaust to again entrain more pollutants from the furnace where they are combined with the fluid (waste water) and directed to the filter system.

  1. Air suctioning during colon biopsy acquisition reduces bacterial contamination

    OpenAIRE

    Vavricka, S; Tutuian, R; Imhof, A.; Wildi, S; Gubler, C; Fruehauf, H; Ruef, C; Fried, M

    2006-01-01

    Background and Aim: Contamination of endoscopy suites with bacteria during procedures is of concern particularly through droplets during handling of biopsy specimens. It has been advocated that suctioning while removing the biopsy forceps could help to reduce potentially hazardous bioaerosols. The aim of the present study was to evaluate the efficacy of air suctioning during removal of the biopsy forceps. Materials and Methods: Airborne bacteria were collected by an impactor air-sampler (MAS-...

  2. RADIAL COMPUTED TOMOGRAPHY OF AIR CONTAMINANTS USING OPTICAL REMOTE SENSING

    Science.gov (United States)

    The paper describes the application of an optical remote-sensing (ORS) system to map air contaminants and locate fugitive emissions. Many ORD systems may utilize radial non-overlapping beam geometry and a computed tomography (CT) algorithm to map the concentrations in a plane. In...

  3. System calibration for air control of radioactive gases [contamination control

    International Nuclear Information System (INIS)

    Testing of the system for air contamination control at the RA reactor was done and calibrated by Ar41. This report contains the report on testing and calibration. This activity was necessary in order to achieve its performance with existing dosimetry system in the RA reactor building

  4. OPEN AIR DEMOLITION OF FACILITIES HIGHLY CONTAMINATED WITH PLUTONIUM

    International Nuclear Information System (INIS)

    The demolition of highly contaminated plutonium buildings usually is a long and expensive process that involves decontaminating the building to near free- release standards and then using conventional methods to remove the structure. It doesn't, however, have to be that way. Fluor has torn down buildings highly contaminated with plutonium without excessive decontamination. By removing the select source term and fixing the remaining contamination on the walls, ceilings, floors, and equipment surfaces; open-air demolition is not only feasible, but it can be done cheaper, better (safer), and faster. Open-air demolition techniques were used to demolish two highly contaminated buildings to slab-on-grade. These facilities on the Department of Energy's Hanford Site were located in, or very near, compounds of operating nuclear facilities that housed hundreds of people working on a daily basis. To keep the facilities operating and the personnel safe, the projects had to be creative in demolishing the structures. Several key techniques were used to control contamination and keep it within the confines of the demolition area: spraying fixatives before demolition; applying fixative and misting with a fine spray of water as the buildings were being taken down; and demolishing the buildings in a controlled and methodical manner. In addition, detailed air-dispersion modeling was done to establish necessary building and meteorological conditions and to confirm the adequacy of the proposed methods. Both demolition projects were accomplished without any spread of contamination outside the modest buffer areas established for contamination control. Furthermore, personnel exposure to radiological and physical hazards was significantly reduced by using heavy equipment rather than ''hands on'' techniques

  5. OPEN AIR DEMOLITION OF FACILITIES HIGHLY CONTAMINATED WITH PLUTONIUM

    Energy Technology Data Exchange (ETDEWEB)

    LLOYD, E.R.

    2007-05-31

    The demolition of highly contaminated plutonium buildings usually is a long and expensive process that involves decontaminating the building to near free- release standards and then using conventional methods to remove the structure. It doesn't, however, have to be that way. Fluor has torn down buildings highly contaminated with plutonium without excessive decontamination. By removing the select source term and fixing the remaining contamination on the walls, ceilings, floors, and equipment surfaces; open-air demolition is not only feasible, but it can be done cheaper, better (safer), and faster. Open-air demolition techniques were used to demolish two highly contaminated buildings to slab-on-grade. These facilities on the Department of Energy's Hanford Site were located in, or very near, compounds of operating nuclear facilities that housed hundreds of people working on a daily basis. To keep the facilities operating and the personnel safe, the projects had to be creative in demolishing the structures. Several key techniques were used to control contamination and keep it within the confines of the demolition area: spraying fixatives before demolition; applying fixative and misting with a fine spray of water as the buildings were being taken down; and demolishing the buildings in a controlled and methodical manner. In addition, detailed air-dispersion modeling was done to establish necessary building and meteorological conditions and to confirm the adequacy of the proposed methods. Both demolition projects were accomplished without any spread of contamination outside the modest buffer areas established for contamination control. Furthermore, personnel exposure to radiological and physical hazards was significantly reduced by using heavy equipment rather than ''hands on'' techniques.

  6. An experimental study on gelfoam contamination in the room air

    International Nuclear Information System (INIS)

    To evaluate the air contamination of the gelfoam in the angio-intervention room. After exposing four groups of gelfoam(group A1 : gelfoam fragment, group A2 : gelfoam fragment + saline + contrast media, group B1 : gelfoam powder, group B2 : gelfoam powder + saline + contrast media) to air in the angio-intervention room, we inoculated gelfoam in each group to 30 agar plates each at every fifteen minutes for one hour with aseptic cotton buds. Cultivating them in the incubator for one day, we evaluated the growth of bacteria or fungus. Out of 480 inoculated agar plates, the growth of coagulase(-) staphylococci was visible in 14 ; in group A1, two at 30 minutes, three at 45 minutes, and four at 60 minutes ; in group A2, one at 45 minutes and two at 60 minutes ; in group B1 and B2, one each at 45 minutes. The statistical analysis on bacterial contamination according to time sequence and group revealed no significance(p>0.05). If gelfoam is exposed to room air for less than 30 minutes, it is possible to reduce contamination by air-borne bacteria. Since coagulase-negative Staphylococci resistant to commonly used antibiotics, it is ideal to reduce exposure of gelfoam to room air for less than 30 minutes

  7. Circumventing shallow air contamination in Mid Ocean Ridge Basalts

    Science.gov (United States)

    Mukhopadhyay, Sujoy; Parai, Rita; Tucker, Jonathan; Middleton, Jennifer; Langmuir, Charles

    2016-04-01

    Noble gases in mantle-derived basalts provide a rich portrait of mantle degassing and surface-interior volatile exchange. However, the ubiquity of shallow-level air contamination frequently obscures the mantle noble gas signal. In a majority of samples, shallow air contamination dominates the noble gas budget. As a result, reconstructing the variability in heavy noble gas mantle source compositions and inferring the history of deep recycling of atmospheric noble gases is difficult. For example, in the gas-rich popping rock 2ΠD43, 129Xe/130Xe ratios reach 7.7±0.23 in individual step-crushes, but the bulk composition of the sample is close to air (129Xe/130Xe of 6.7). Here, we present results from experiments designed to elucidate the source of shallow air contamination in MORBs. Step-crushes were carried out to measure He, Ne, Ar and Xe isotopic compositions on two aliquots of a depleted popping glass that was dredged from between the Kane and Atlantis Fracture Zones of the Mid-Atlantic Ridge in May 2012. One aliquot was sealed in ultrapure N2 after dredge retrieval, while the other aliquot was left exposed to air for 3.5 years. The bulk 20Ne/22Ne and 129Xe/130Xe ratios measured in the aliquot bottled in ultrapure N2 are 12.3 and 7.6, respectively, and are nearly identical to the estimated mantle source values. On the other hand, step crushes in the aliquot left exposed to air for several years show Ne isotopic compositions that are shifted towards air, with a bulk 20Ne/22Ne of 11.5; the bulk 129Xe/130Xe, however, was close to 7.6. These results indicate that lighter noble gases exchange more efficiently between the bubbles trapped in basalt glass and air, suggesting a diffusive or kinetic mechanism for the incorporation of the shallow air contamination. Importantly, in Ne-Ar or Ar-Xe space, step-crushes from the bottled aliquot display a trend that can be easily fit with a simple two-component hyperbolic mixing between mantle and atmosphere noble gases. Step

  8. Microorganisms in stable air as possible postsecretory milk contaminants

    Directory of Open Access Journals (Sweden)

    Kristina Matković

    2006-12-01

    Full Text Available Quality and hygienic correct milk must satisfy conditions which are prescribed by Law on Raw Milk Quality (NN102/2000. If we know that freshly milked milk could contain a certain number of microorganisms originating from the stable air (so called postsecretory contamination, performed research can help in establishing microclimatic factors that can influence that kind of contamination. Research was carried out in a dairy stable, basic microclimatic parameters were analyzed as well as number of microorganisms in the stable air. Measurements were executed in the morning, at noon and in the evening, once a week, during two months. Microclimate parameters were determined by standard, attested Testo 400 device (Testo Inc., Germany and Merck MAS-100 device (Merck KgaA, Darmstadt, Germany. Air samples were inoculated on prepared Columbia and Sabouraud agar (Biolife, Milan, Italy. After incubation and counting, the most common colonies were reinoculated on selective medium and identified by microbiological procedures. Obtained values were analyzed by statistical program Statistica. Mean values of total bacterial count in stable air were between 8.81 x 104 CFU/m3 at noon up to 1.26 x 105 CFU/m3 in the evening, and mean values of total moulds count in stable air were between 5.23 x 104 CFU/m3 at noon up to 8.35 x 104 CFU/m3 in the morning. Ten bacterial genus’s were identified. The most common bacteria in stable air were gram-positive bacteria, specially Staphylococcus i Streptococcus genera. Nine mould genera were isolated, predominated by the genera Aspergillus, Penicillium and yeasts. By Wilcoxon matched pair test at a level of statistical significance of p<0.05 was demonstrated that air temperature, relative humidity and air flow velocity directly influence on total number of microorganisms in stable air. Number and species of identified microorganisms in stable air could have influence on hygiene quality of fresh milk. Therefore, by regularly

  9. Assessment of the bacterial contamination of hand air dryer in washrooms

    OpenAIRE

    Alharbi, Sulaiman Ali; Salmen, Saleh Hussein; Chinnathambi, Arunachalam; Alharbi, Naiyf S.; Zayed, M.E.; Al-Johny, Bassam O.; Wainwright, Milton

    2015-01-01

    The present study was carried out, using standard techniques, to identify and count the bacterial contamination of hand air dryers, used in washrooms. Bacteria were isolated from the air flow, outlet nozzle of warm air dryers in fifteen air dryers used in these washrooms. Bacteria were found to be relatively numerous in the air flows. Bacterially contaminated air was found to be emitted whenever a warm air dryer was running, even when not being used for hand drying. Our investigation shows th...

  10. Recommended Concentration Limits of Typical Indoor Air Contaminants

    Institute of Scientific and Technical Information of China (English)

    LV Chao; JIANG Yun-tao; ZHAO Jia-ning

    2009-01-01

    From the view of both objective and subjective factors.the indoor air quality(IAQ)evaluation was considered.Carbon dioxide (CO2) and formaldehyde (HCHO) were selected as the typical contaminants of indoor air,and the evaluation method of logarithmic index was adopted as the evaluation means of IAQ.Then the recommended limits (RL) of typical contaminants CO2 and HCHO were given through analysis and calcula-tion.The limits of CO2 and HCHO in Indoor Air Quahty Standard of China or other existing standards probably correspond to the level of PD=25(%).The result shows that the existing standards fail to meet the require-ment of the definition of"acceptable indoor air quality",that is to say,less than 20% of the people express dis-satisfaction.When PD=20%,RL of CO2 and HCHO are 728×10-6 and 0.068×10-6 respectively,which are stricter than the limits in the existing standards.The method proposed in this paper is applicable to 13.1%≤PD≤86.7%.

  11. Measurement of radioactive soil contamination from the air

    International Nuclear Information System (INIS)

    In-situ gamma spectrometry can be used to determine the qualitative and quantitative deposition of radioactive materials on the ground surface. By applying the in-situ spectrometry method using either a helicopter or an airplane, large areas can be scanned in a short period of time. In this report the results of in-situ gamma spectroscopic measurements taken from a helicopter are described. Measurements were carried out using a single point source, a field of 36 point sources, and using the present ground contamination due to fall-out from the Chernobyl accident and atom bombs. The results of these measurements were used to determine calibration factors, which were in agreement with a calibration obtained using more simple (and less expensive) laboratory measurements in combination with flux calculations. Detection limits for the measurement of surface contamination were determined. At a height of 50 meters above the surface and using a measurement time of 2 minutes, the minimally detectable surface contamination was 1.1 kBqm-2 for a Cs-137 contamination and 2.1 kBqm-2 for I-131 contamination. Fall-out determinations based on measurements taken at a height of 50 meters were in agreement with determinations taken at a height of 1 meter, and with the results obtained measuring soil samples. The in-situ gamma spectroscopy, using helicopter or airplane, is a fast and powerful method for mapping surface contamination. (author). 13 refs.; 18 figs.; 13 tabs

  12. Ozone production by a dc corona discharge in air contaminated by n-heptane

    International Nuclear Information System (INIS)

    Beneficial purposes of ozone such as elimination of odours, harmful bacteria and mildew can be used for transportation of food, fruits and vegetables with the aim to extend their storage life. To date the main technique used for this purpose in the transportation of these commodities, e.g. by trucks, was cooling. Here a combination of cooling together with the supply of ozone into containers with these commodities is considered. For these purposes we studied the effect of air contamination by n-heptane (part of automotive fuels) and humidity on ozone production by a dc hollow needle to mesh corona discharge. We found that, for both polarities of the needle electrode, addition of n-heptane to air (a) decreases ozone production; (b) causes discharge poisoning to occur at lower current than for air; (c) does not substantially influence the current for which the ozone production reaches the maximum. Finally the maximum ozone production for the discharge in air occurs for the same current as the maximum ozone production for the discharge contaminated by n-heptane. We also found that humidity decreases ozone production from air contaminated by n-heptane irrespective of the polarity of the coronating needle electrode. This dependence is stronger for the discharge with the needle biased positively

  13. Ozone production by a dc corona discharge in air contaminated by n-heptane

    Science.gov (United States)

    Pekárek, S.

    2008-01-01

    Beneficial purposes of ozone such as elimination of odours, harmful bacteria and mildew can be used for transportation of food, fruits and vegetables with the aim to extend their storage life. To date the main technique used for this purpose in the transportation of these commodities, e.g. by trucks, was cooling. Here a combination of cooling together with the supply of ozone into containers with these commodities is considered. For these purposes we studied the effect of air contamination by n-heptane (part of automotive fuels) and humidity on ozone production by a dc hollow needle to mesh corona discharge. We found that, for both polarities of the needle electrode, addition of n-heptane to air (a) decreases ozone production; (b) causes discharge poisoning to occur at lower current than for air; (c) does not substantially influence the current for which the ozone production reaches the maximum. Finally the maximum ozone production for the discharge in air occurs for the same current as the maximum ozone production for the discharge contaminated by n-heptane. We also found that humidity decreases ozone production from air contaminated by n-heptane irrespective of the polarity of the coronating needle electrode. This dependence is stronger for the discharge with the needle biased positively.

  14. Ozone production by a dc corona discharge in air contaminated by n-heptane

    Energy Technology Data Exchange (ETDEWEB)

    Pekarek, S [Czech Technical University, FEE, Technicka 2, 166 27 Prague 6 (Czech Republic)

    2008-01-21

    Beneficial purposes of ozone such as elimination of odours, harmful bacteria and mildew can be used for transportation of food, fruits and vegetables with the aim to extend their storage life. To date the main technique used for this purpose in the transportation of these commodities, e.g. by trucks, was cooling. Here a combination of cooling together with the supply of ozone into containers with these commodities is considered. For these purposes we studied the effect of air contamination by n-heptane (part of automotive fuels) and humidity on ozone production by a dc hollow needle to mesh corona discharge. We found that, for both polarities of the needle electrode, addition of n-heptane to air (a) decreases ozone production; (b) causes discharge poisoning to occur at lower current than for air; (c) does not substantially influence the current for which the ozone production reaches the maximum. Finally the maximum ozone production for the discharge in air occurs for the same current as the maximum ozone production for the discharge contaminated by n-heptane. We also found that humidity decreases ozone production from air contaminated by n-heptane irrespective of the polarity of the coronating needle electrode. This dependence is stronger for the discharge with the needle biased positively.

  15. Methodology for modeling the microbial contamination of air filters.

    Directory of Open Access Journals (Sweden)

    Yun Haeng Joe

    Full Text Available In this paper, we propose a theoretical model to simulate microbial growth on contaminated air filters and entrainment of bioaerosols from the filters to an indoor environment. Air filter filtration and antimicrobial efficiencies, and effects of dust particles on these efficiencies, were evaluated. The number of bioaerosols downstream of the filter could be characterized according to three phases: initial, transitional, and stationary. In the initial phase, the number was determined by filtration efficiency, the concentration of dust particles entering the filter, and the flow rate. During the transitional phase, the number of bioaerosols gradually increased up to the stationary phase, at which point no further increase was observed. The antimicrobial efficiency and flow rate were the dominant parameters affecting the number of bioaerosols downstream of the filter in the transitional and stationary phase, respectively. It was found that the nutrient fraction of dust particles entering the filter caused a significant change in the number of bioaerosols in both the transitional and stationary phases. The proposed model would be a solution for predicting the air filter life cycle in terms of microbiological activity by simulating the microbial contamination of the filter.

  16. Reactive Distillation and Air Stripping Processes for Water Recycling and Trace Contaminant Control

    Science.gov (United States)

    Boul, Peter J.; Lange, Kevin E.; Conger, Bruce; Anderson, Molly

    2009-01-01

    Reactive distillation designs are considered to reduce the presence of volatile organic compounds in the purified water. Reactive distillation integrates a reactor with a distillation column. A review of the literature in this field has revealed a variety of functional reactive columns in industry. Wastewater may be purified by a combination of a reactor and a distiller (e.g., the EWRS or VPCAR concepts) or, in principle, through a design which integrates the reactor with the distiller. A review of the literature in reactive distillation has identified some different designs in such combinations of reactor and distiller. An evaluation of reactive distillation and reactive air stripping is presented with regards to the reduction of volatile organic compounds in the contaminated water and air. Among the methods presented, an architecture is presented for the evaluation of the simultaneous oxidation of organics in air and water. These and other designs are presented in light of potential improvements in power consumptions and air and water purities for architectures which include catalytic activity integrated into the water processor. In particular, catalytic oxidation of organics may be useful as a tool to remove contaminants that more traditional distillation and/or air stripping columns may not remove. A review of the current leading edge at the commercial level and at the research frontier in catalytically active materials is presented. Themes and directions from the engineering developments in catalyst design are presented conceptually in light of developments in the nanoscale chemistry of a variety of catalyst materials.

  17. Ambient and Emission Trends of Toxic Air Contaminants in California.

    Science.gov (United States)

    Propper, Ralph; Wong, Patrick; Bui, Son; Austin, Jeff; Vance, William; Alvarado, Álvaro; Croes, Bart; Luo, Dongmin

    2015-10-01

    After initiating a toxic air contaminant (TAC) identification and control program in 1984, the California Air Resources Board adopted regulations to reduce TAC emissions from cars, trucks, stationary sources, and consumer products. This study quantifies ambient concentration and emission trends for the period 1990-2012 for seven TACs that are responsible for most of the known cancer risk associated with airborne exposure in California. Of these seven, diesel particulate matter (DPM) is the most important; however DPM is not measured directly. Based on a novel surrogate method, DPM concentrations declined 68%, even though the state's population increased 31%, diesel vehicle-miles-traveled increased 81%, and the gross state product (GSP) increased 74%. Based on monitoring data, concentrations of benzene, 1,3-butadiene, perchloroethylene, and hexavalent chromium declined 88-94%. Also, the ambient and emissions trends for each of these four TACs were similar. Furthermore, these declines generally occurred earlier in California than elsewhere. However, formaldehyde and acetaldehyde, which are formed in the air photochemically from volatile organic compounds (VOCs), declined only 20-21%. The collective cancer risk from exposure to these seven reviewed TACs declined 76%. Significant reduction in cancer risk to California residents from implementation of air toxics controls (especially for DPM) is expected to continue. PMID:26340590

  18. Impact of airflow interaction on inhaled air quality and transport of contaminants in rooms with personalized and total volume ventilation

    DEFF Research Database (Denmark)

    Melikov, Arsen Krikor; Cermak, Radim; Kovar, O.;

    2003-01-01

    ventilation. In total, 80 L/s of clean air supplied at 20°C was distributed between the ventilation systems at different combinations of personalized airflow rate. Two breathing thermal manikins were used to simulate occupants in a full-scale test room. Regardless of the airflow interaction, the inhaled air......The impact of airflow interaction on inhaled air quality and transport of contaminants between occupants was studied in regard to pollution from floor covering, human bioeffluents and exhaled air, with combinations of two personalized ventilation systems (PV) with mixing and displacement...... quality with personalized and mixing ventilation was higher or at least similar compared to mixing ventilation alone. In the case of PV combined with displacement ventilation, the interaction caused mixing of the room air, an increase in the transport of bioeffluents and exhaled air between occupants and...

  19. Impacts of air, water and soil contamination on forests

    International Nuclear Information System (INIS)

    The result of our literature search is presented; it deals with the measuring points and screens used in the former GDR to determine the stress of the forests by air pollution (immissions, depositions, soil contamination, stress of waters, biological monitoring). In the second part we present the results of our search regarding the research done in the former GDR on methods of forest damage survey, on material balance of forest ecosystems, on modifications in the forest soile caused by depositions, on the possible impacts on the quality of waters, and on the influence of liming and fertilizer application on the material balance of forest stands damaged by immissions. Proposals are made for further research. (orig.)

  20. Removal of So2 from Contaminated Air Using a Peat Biofilter

    OpenAIRE

    Kristina Skemundrytė; Rasa Vaiškūnaitė

    2013-01-01

    About 64 thousand tons of contaminated air is annually released into ambient air. More than 30% of such pollution includes toxic sulfur compounds. The article discusses the properties of biofiltration - biological air cleaning technology. Research was performed using a biofilter produced in the laboratory at Vilnius Gediminas Technical University. During testing, ambient air contaminated with sulfur dioxide was pulled through biomedia with a division of Thiobacillus microorganisms, and calcul...

  1. Methods for Sampling and Measurement of Compressed Air Contaminants

    Energy Technology Data Exchange (ETDEWEB)

    Stroem, L.

    1976-10-15

    In order to improve the technique for measuring oil and water entrained in a compressed air stream, a laboratory study has been made of some methods for sampling and measurement. For this purpose water or oil as artificial contaminants were injected in thin streams into a test loop, carrying dry compressed air. Sampling was performed in a vertical run, down-stream of the injection point. Wall attached liquid, coarse droplet flow, and fine droplet flow were sampled separately. The results were compared with two-phase flow theory and direct observation of liquid behaviour. In a study of sample transport through narrow tubes, it was observed that, below a certain liquid loading, the sample did not move, the liquid remaining stationary on the tubing wall. The basic analysis of the collected samples was made by gravimetric methods. Adsorption tubes were used with success to measure water vapour. A humidity meter with a sensor of the aluminium oxide type was found to be unreliable. Oil could be measured selectively by a flame ionization detector, the sample being pretreated in an evaporation- condensation unit

  2. Methods for Sampling and Measurement of Compressed Air Contaminants

    International Nuclear Information System (INIS)

    In order to improve the technique for measuring oil and water entrained in a compressed air stream, a laboratory study has been made of some methods for sampling and measurement. For this purpose water or oil as artificial contaminants were injected in thin streams into a test loop, carrying dry compressed air. Sampling was performed in a vertical run, down-stream of the injection point. Wall attached liquid, coarse droplet flow, and fine droplet flow were sampled separately. The results were compared with two-phase flow theory and direct observation of liquid behaviour. In a study of sample transport through narrow tubes, it was observed that, below a certain liquid loading, the sample did not move, the liquid remaining stationary on the tubing wall. The basic analysis of the collected samples was made by gravimetric methods. Adsorption tubes were used with success to measure water vapour. A humidity meter with a sensor of the aluminium oxide type was found to be unreliable. Oil could be measured selectively by a flame ionization detector, the sample being pretreated in an evaporation- condensation unit

  3. Assessment of combined electro-nanoremediation of molinate contaminated soil.

    Science.gov (United States)

    Gomes, Helena I; Fan, Guangping; Mateus, Eduardo P; Dias-Ferreira, Celia; Ribeiro, Alexandra B

    2014-09-15

    Molinate is a pesticide widely used, both in space and time, for weed control in rice paddies. Due to its water solubility and affinity to organic matter, it is a contaminant of concern in ground and surface waters, soils and sediments. Previous works have showed that molinate can be removed from soils through electrokinetic (EK) remediation. In this work, molinate degradation by zero valent iron nanoparticles (nZVI) was tested in soils for the first time. Soil is a highly complex matrix, and pollutant partitioning between soil and water and its degradation rates in different matrices is quite challenging. A system combining nZVI and EK was also set up in order to study the nanoparticles and molinate transport, as well as molinate degradation. Results showed that molinate could be degraded by nZVI in soils, even though the process is more time demanding and degradation percentages are lower than in an aqueous solution. This shows the importance of testing contaminant degradation, not only in aqueous solutions, but also in the soil-sorbed fraction. It was also found that soil type was the most significant factor influencing iron and molinate transport. The main advantage of the simultaneous use of both methods is the molinate degradation instead of its accumulation in the catholyte. PMID:24946031

  4. Assessment of combined electro–nanoremediation of molinate contaminated soil

    Energy Technology Data Exchange (ETDEWEB)

    Gomes, Helena I., E-mail: hrg@campus.fct.unl.pt [CENSE, Departamento de Ciências e Engenharia do Ambiente, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica (Portugal); CERNAS — Research Center for Natural Resources, Environment and Society, Escola Superior Agraria de Coimbra, Instituto Politecnico de Coimbra, Bencanta, 3045-601 Coimbra (Portugal); Fan, Guangping [CENSE, Departamento de Ciências e Engenharia do Ambiente, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica (Portugal); Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences (ISSCAS), East Beijing Road, Nanjing 210008 (China); Mateus, Eduardo P. [CENSE, Departamento de Ciências e Engenharia do Ambiente, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica (Portugal); Dias-Ferreira, Celia [CERNAS — Research Center for Natural Resources, Environment and Society, Escola Superior Agraria de Coimbra, Instituto Politecnico de Coimbra, Bencanta, 3045-601 Coimbra (Portugal); Ribeiro, Alexandra B. [CENSE, Departamento de Ciências e Engenharia do Ambiente, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica (Portugal)

    2014-09-15

    Molinate is a pesticide widely used, both in space and time, for weed control in rice paddies. Due to its water solubility and affinity to organic matter, it is a contaminant of concern in ground and surface waters, soils and sediments. Previous works have showed that molinate can be removed from soils through electrokinetic (EK) remediation. In this work, molinate degradation by zero valent iron nanoparticles (nZVI) was tested in soils for the first time. Soil is a highly complex matrix, and pollutant partitioning between soil and water and its degradation rates in different matrices is quite challenging. A system combining nZVI and EK was also set up in order to study the nanoparticles and molinate transport, as well as molinate degradation. Results showed that molinate could be degraded by nZVI in soils, even though the process is more time demanding and degradation percentages are lower than in an aqueous solution. This shows the importance of testing contaminant degradation, not only in aqueous solutions, but also in the soil-sorbed fraction. It was also found that soil type was the most significant factor influencing iron and molinate transport. The main advantage of the simultaneous use of both methods is the molinate degradation instead of its accumulation in the catholyte. - Highlights: • Molinate is degraded in soil by zero valent iron nanoparticles (nZVI). • Higher contact time of nZVI with soil facilitates molinate degradation. • Soil type was the most significant factor influencing iron and molinate transport. • When using nZVI and EK molinate is not only transported to catholyte, but also degraded.

  5. Assessment of combined electro–nanoremediation of molinate contaminated soil

    International Nuclear Information System (INIS)

    Molinate is a pesticide widely used, both in space and time, for weed control in rice paddies. Due to its water solubility and affinity to organic matter, it is a contaminant of concern in ground and surface waters, soils and sediments. Previous works have showed that molinate can be removed from soils through electrokinetic (EK) remediation. In this work, molinate degradation by zero valent iron nanoparticles (nZVI) was tested in soils for the first time. Soil is a highly complex matrix, and pollutant partitioning between soil and water and its degradation rates in different matrices is quite challenging. A system combining nZVI and EK was also set up in order to study the nanoparticles and molinate transport, as well as molinate degradation. Results showed that molinate could be degraded by nZVI in soils, even though the process is more time demanding and degradation percentages are lower than in an aqueous solution. This shows the importance of testing contaminant degradation, not only in aqueous solutions, but also in the soil-sorbed fraction. It was also found that soil type was the most significant factor influencing iron and molinate transport. The main advantage of the simultaneous use of both methods is the molinate degradation instead of its accumulation in the catholyte. - Highlights: • Molinate is degraded in soil by zero valent iron nanoparticles (nZVI). • Higher contact time of nZVI with soil facilitates molinate degradation. • Soil type was the most significant factor influencing iron and molinate transport. • When using nZVI and EK molinate is not only transported to catholyte, but also degraded

  6. Sources of indoor air contamination on the ground floor of a high-rise commercial building

    International Nuclear Information System (INIS)

    Indoor air quality is a subject of growing concern in the developed world. Many sources of indoor air contamination in commercial and office buildings are recognised and have been investigated. In addition to the usual internal sources of air contaminants, other external sources from attached facilities can find their way into the building. This report presents the results of an indoor air quality survey in a high-rise office building which demonstrated an obvious seasonal change in regard to the concentrations of carbon dioxide (CO2), nitric oxide (NO) and nitrogen dioxide (NO2). Furthermore, a complementary survey in the same building was carried out to identify the relevant sources of air contamination in the building and the results indicated that an attached train station and the nearby street traffic had a significant impact on indoor air quality. (author)

  7. Air Sampling Instruments for Evaluation of Atmospheric Contaminants. Fourth Edition.

    Science.gov (United States)

    American Conference of Governmental Industrial Hygienists, Cincinnati, OH.

    This text, a revision and extension of the first three editions, consists of papers discussing the basic considerations in sampling air for specific purposes, sampler calibration, systems components, sample collectors, and descriptions of air-sampling instruments. (BT)

  8. Radiation contamination air monitoring basing on NATO normalization documents

    International Nuclear Information System (INIS)

    The conditions and actions connected with conducting of the air radiation monitoring have been described in the article. The staff and tasks of special military troops for air sampling as well as commonly used methods for air sampling have been presented and discussed

  9. Study on influence of characteristics of air-supply jet on drain contamination efficiency and air quality in heading

    Institute of Scientific and Technical Information of China (English)

    LIU He-qing; SHI Shi-liang; LIU Rong-hua; WANG H ai-qiao

    2001-01-01

    Based on the theory of air-supply jet, the conception and theory o f the air quality and the drain-contamination efficiency, the results achieved b y comparing the circular cross-section wall jet with the plane wall jet were fo l lowing: firstly, within the limitation of the ventilation distance at the tunnel heading in a coal mine, there were a better air quality and a higher efficiency of drain-contamination with application of the plane wall jet ventilation. Sec o ndly, there was a advantage to improve the air quality of the workers breathin g area with mounting the air-supply outlet on the top but not on the side of the tunnel heading.

  10. Report of Findings: Cold Bay Air Force Station (Grant Point) military contaminants: Fiscal year 1988 collections

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report summarizes our contaminants investigation at the abandoned Cold Bay Air Force Station Station, located on the Izembek National Wildlife Refuge at Grant...

  11. (Environmental investigation of ground water contamination at Wright-Patterson Air Force Base, Ohio)

    Energy Technology Data Exchange (ETDEWEB)

    1991-10-01

    This report presents information concerning field procedures employed during the monitoring, well construction, well purging, sampling, and well logging at the Wright-Patterson Air Force Base. Activities were conducted in an effort to evaluate ground water contamination.

  12. An Assessment of Air As a Source of DNA Contamination Encountered When Performing PCR

    OpenAIRE

    Witt, Nina; Rodger, Gillian; Vandesompele, Jo; Benes, Vladimir; Zumla, Alimuddin; Rook, Graham A.; Huggett, Jim F

    2009-01-01

    Sensitive molecular methods, such as the PCR, can detect low-level contamination, and careful technique is required to reduce the impact of contaminants. Yet, some assays that are designed to detect high copy-number target sequences appear to be impossible to perform without contamination, and frequently, personnel or laboratory environment are held responsible as the source. This complicates diagnostic and research analysis when using molecular methods. To investigate the air specifically as...

  13. Air contaminant statistical distributions with application to PM10 in Santiago, Chile.

    Science.gov (United States)

    Marchant, Carolina; Leiva, Víctor; Cavieres, M Fernanda; Sanhueza, Antonio

    2013-01-01

    The use of statistical distributions to predict air quality is valuable for determining the impact of air chemical contaminants on human health. Concentrations of air pollutants are treated as random variables that can be modeled by a statistical distribution that is positively skewed and starts from zero. The type of distribution selected for analyzing air pollution data and its associated parameters depend on factors such as emission source and local meteorology and topography. International environmental guideline use appropriate distributions to compute exceedance probabilities and percentiles for setting administrative targets and issuing environmental alerts. The distribution bears a relationship to the normal distribution, and there are theoretical - and physical-based mechanistic arguments that support its use when analyzing air-pollutant data. Others distribution have also been used to model air population data, such as the beta, exponential, gamma, Johnson, log-logistic, Pearson, and Weibull distribution. One model also developed from physical-mechanistic considerations that has received considerable interest in recent year is the Birnbaum-Saunders distribution. This distribution has theoretical arguments and properties similar to those of the log-normal distribution, which renders it useful for modeling air contamination data. In this review, we have addressed the range of common atmospheric contaminants and the health effects they cause. We have also reviewed the statistical distributions that have been use to model air quality, after which we have detailed the problem of air contamination in Santiago, Chile. We have illustrated a methodology that is based on the Birnbaum-Saunders distributions to analyze air contamination data from Santiago, Chile. Finally, in the conclusions, we have provided a list of synoptic statements designed to help readers understand the significance of air pollution in Chile, and in Santiago, in particular, but that can be

  14. Air way of food stuffs contamination with radionuclides

    International Nuclear Information System (INIS)

    Considered is the surface contamination of the land part of plants with the fixation of radionuclides on the surface and partial penetration in the vegetable tissue. The retention of radioactive particles from atmospheric fallouts on plants depends on the nature of vegetation (foliage thickness, the shape of leaves), meteorologic conditions and physicochemical properties of particles. The transition of radioactive substances in edible parts of plants is also discussed. Determination of the clearance rate of plants from radionuclides is discussed. Periods of importance of the surface contamination are shown

  15. Techniques for the measurement of the contamination of air

    International Nuclear Information System (INIS)

    This lecture has been given at the International Symposium of Riso 1959. Methods for measuring radioactive content of the atmosphere are described, and main results found at Saclay are given, for the following contaminants: Rn, Tn and their daughter, H-3, C-14, A-41, Kr-85, I-131, and fission products as a whole. (author)

  16. Modeling, estimation, fault detection and fault diagnosis of spacecraft air contaminants

    Science.gov (United States)

    Narayan, Anand P.

    1998-07-01

    The objective of this dissertation is to develop a framework for the modeling, estimation, fault detection and diagnosis of air contaminants aboard spacecraft. Safe air is a vital resource aboard spacecraft for crewed missions, and especially so in long range missions, where the luxury of returning to earth for a clean-up does not exist. This research uses modern control theory in conjunction with advanced fluid mechanics to achieve the objective of developing an implementable comprehensive monitoring systems, suitable for use on space missions. First, a three-dimensional transport model is developed in order to model the dispersion of air contaminants. The flow field, which is an important input to the transport model, is obtained by solving the Navier Stokes equations for the cabin geometry and the appropriate boundary conditions, using a finite element method. Steady flow fields are computed for various conditions for both laminar and turbulent cases. Contamination dispersion studies are undertaken both for routine substances introduced through the inlet ducts and for emissions of toxics inside the cabin volume. The dispersion studies indicate that lumped models and even a two-dimensional model are sometimes inadequate to assure that the Spacecraft Maximum Allowable Concentrations (SMACs) are not exceeded locally. Since the research was targeted at real-time application aboard Spacecraft, a state estimation routine is implemented using Implicit Kalman Filtering. The routine makes use of the model predictions and measurements from the sensor system in order to arrive at an optimal estimate of the state of the system for each time step. Fault detection is accomplished through the use of analytical redundancy, where error residuals from the Kalman filter are monitored in order to detect any faults in the system, and to distinguish between sensor and process faults. Finally, a fault diagnosis system is developed, which is a combination of sensitivity analysis and an

  17. The major regularities of the air radioactive contamination of Belarus territory after the Chernobyl accident

    International Nuclear Information System (INIS)

    In the first days after the Chernobyl accident the radioactivity of surface air in different regions of Belarus has increased in tens and hundred thousand time. The regular control of air radioactive contamination in the zone of alienation and nearest to it is carried out from the end 1989. The radioactive air monitoring carried out in territories with various contamination density (from 0,2 up to 9,6 MBq/m2 on Cs-137). The measurements of the Cs-137 contents in ashes of air sampler filters were carried out by gamma - spectrometer ADCAM-300 MCA. The measurement of the Pu-240,239 and Sr-90 contents was carried out by usual radiochemical techniques. The used techniques and equipment allow to define in a sample of the minimal activity: Pu-239,240 - 0,001 Bq, Cs-137 - 0,5 Bq, Sr-90 - 0,1 Bq. The initial contamination of ground happened a near zone within approximately first 2 weeks after accident. Since the end of May, 1986 till present time the air radioactive contamination is formed under action of processes of secondary wind rise and carry of radioactive particles with contaminated territories, which depends from a number factors of both natural and anthropogenous origin. The relations of Pu-238/Pu-239 and Sr-90/Pu-239 in aerosol particles practically coincide with the same relations in fuel blown up reactor. The ratio of Cs-137/Pu-239 activities in aerosols considerably exceeds the resettlement ratio for fuel. Strontium and plutonium are in structure of fuel particles, and cesium aerosol have other origin. The analysis of changes annual radioisotopes concentration in air of towns of Belarus specifies existence of the tendency to slow decrease of contamination of atmosphere by radioisotopes of industrial origins. The basic tendency of formation of air radioactive contamination is determined by the contents of a dust at surface layer of an atmosphere and its specific activity. Annual average dust content of air in a zone resettlement was least and made about 10 mk g

  18. Microbial contamination and effects of combination treatments and gamma irradiation on reducing microbial contamination of dried cuttle fish

    International Nuclear Information System (INIS)

    Dried cuttle fish is one of the most valuable sea products but it rapidly becomes mouldy and spoiled. To solve this problem, the studies on microbial contamination and effects of combination treatments and gamma irradiation for dried cuttle fish have been caried out base on IAEA Research Contracts No 4397/AG and 4397/R1/AG

  19. Techniques for the measurement of the contamination of air; Technique de mesure de la contamination de l'air

    Energy Technology Data Exchange (ETDEWEB)

    Labeyrie, J. [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires

    1960-07-01

    This lecture has been given at the International Symposium of Riso 1959. Methods for measuring radioactive content of the atmosphere are described, and main results found at Saclay are given, for the following contaminants: Rn, Tn and their daughter, H-3, C-14, A-41, Kr-85, I-131, and fission products as a whole. (author) [French] Ce texte est celui d'une conference-rapport prononcee au Colloque International de Riso en 1959. On indique les techniques de mesures de la contamination radioactive de l'atmosphere et les principaux resultats obtenus jusqu'ici au CEA pour: Rn et Tn et leurs derives, H-3, C-14, A-41, Kr-85, I-131, et l'ensemble des produits de fission. (auteur)

  20. A Simple DSA Method to Detect Air Contamination During CO2 Venous Studies

    International Nuclear Information System (INIS)

    The use of CO2 as a contrast agent has increased significantly for visualization of the central veins, inferior vena cava, and portal vein. The most serious complication associated with CO2 studies is air contamination. We evaluated a simple digital subtraction angiogram (DSA) method to detect air contamination during CO2 venous studies. After injections of 5, 10, and 20 cm3 of CO2 and 5 cm3 of air into the inferior vena cavas of five domestic swine in the left lateral decubitus position, a DSA was performed using the cross-table lateral projection to visualize the gases trapped in the right atrium. The time to complete dissolution of CO2 at increased doses was compared to that of air. Vital signs were observed during and after CO2 or air injection. In all animals, DSA showed the trapped gas outlining the wall of the right atrium. Five cubic centimeters of CO2 was cleared from the right atrium in an average of 46 sec (21-60 sec), whereas 5 cm3 of air remained visible over 5 min. Ascending doses of CO2 increased the time of dissolution to 54 sec (47-67 sec) for 10 cm3 and 70 sec (45-90 sec) for 45 cm3. Vital signs remained stable during the study. Using DSA, CO2 can be distinguished from air by demonstrating rapid absorption of the former, thus allowing detection of air contamination during CO2 venous studies. If the gases trapped in the right atrium remain visible 90 sec after the injection, air contamination should be suspected

  1. Ventilation as mitigation of PCB contaminated air in buildings

    DEFF Research Database (Denmark)

    Lyng, Nadja; Trap, Niels; Andersen, Helle Vibeke;

    2014-01-01

    measured in the same room at least twice and under different ventilation conditions. In general, PCB concentrations decrease with increased ventilation making the effect of ventilation to reduce human exposure feasible. In 26 case rooms, the mean reduction of the concentration was found to be 51% (median...... In the remaining four cases, the pressure difference between the room measured and the surroundings showed a tremendous effect on the concentration as opposed to the effect of ventilation. Pressure differences might affect the emission of PCB by motion of air through gaps and cracks along the PCB sealants. were...... of ventilation. Pressure differences might affect the emission of PCB by motion of air through gaps and cracks along the PCB sealants....

  2. Impacts of contaminant storage on indoor air quality: Model development

    Science.gov (United States)

    Sherman, Max H.; Hult, Erin L.

    2013-06-01

    A first-order, lumped capacitance model is used to describe the buffering of airborne chemical species by building materials and furnishings in the indoor environment. The model is applied to describe the interaction between formaldehyde in building materials and the concentration of the species in the indoor air. Storage buffering can decrease the effect of ventilation on the indoor concentration, compared to the inverse dependence of indoor concentration on the air exchange rate that is consistent with a constant emission rate source. If the exposure time of an occupant is long relative to the timescale of depletion of the compound from the storage medium, however, the total exposure will depend inversely on the air exchange rate. This lumped capacitance model is also applied to moisture buffering in the indoor environment, which occurs over much shorter depletion timescales of the order of days. This model provides a framework to interpret the impact of storage buffering on time-varying concentrations of chemical species and resulting occupant exposure. Pseudo-steady-state behavior is validated using field measurements. Model behavior over longer times is consistent with formaldehyde and moisture concentration measurements in previous studies.

  3. Impacts of contaminant storage on indoor air quality: Model development

    Energy Technology Data Exchange (ETDEWEB)

    Sherman, Max H.; Hult, Erin L.

    2013-02-26

    A first-order, lumped capacitance model is used to describe the buffering of airborne chemical species by building materials and furnishings in the indoor environment. The model is applied to describe the interaction between formaldehyde in building materials and the concentration of the species in the indoor air. Storage buffering can decrease the effect of ventilation on the indoor concentration, compared to the inverse dependence of indoor concentration on the air exchange rate that is consistent with a constant emission rate source. If the exposure time of an occupant is long relative to the time scale of depletion of the compound from the storage medium, however, the total exposure will depend inversely on the air exchange rate. This lumped capacitance model is also applied to moisture buffering in the indoor environment, which occurs over much shorter depletion timescales of the order of days. This model provides a framework to interpret the impact of storage buffering on time-varying concentrations of chemical species and resulting occupant exposure. Pseudo-steady state behavior is validated using field measurements. Model behavior over longer times is consistent with formaldehyde and moisture concentration measurements in previous studies.

  4. Animal health in areas of combined radioactive and chemical contamination

    International Nuclear Information System (INIS)

    It was found that man-caused accidents and high concentration of industrial facilities in the Ural Region caused considerable accumulation of radionuclides and heavy metals in animals of some relevant areas. These animals were examined for immune system indices and chromosomal aberrations vs. body content of accumulated toxic agents. It was also found that animal oncological morbidity including cattle leucosis is considerably higher in urban regions as compared to areas of relative ecological well-being. A system of actions has been developed to mitigate negative impact of man-caused contamination. (author)

  5. Comparison between indoor and outdoor air contamination levels in residential buildings from passive sampler study

    International Nuclear Information System (INIS)

    The relationships between indoor and outdoor levels of various air contaminants (NO, NO2, SO2 and O3) in 10 non-smoking residential buildings were discussed in this paper. Levels of these four air contaminants from 10 domestic units in Hong Kong were obtained using passive samplers. An integral approach was applied to the mass balance equation and with some approximations, the source and sink strengths of the air contaminants were estimated. It has been found that the average ratios of the indoor and outdoor levels of NO, NO2, SO2 and O3 were 0.98 (S.D. = 0.19), 0.79 (S.D. = 0.30), 1.01 (S.D. = 0.78) and 0.40 (S.D. = 0.31), respectively. The results also indicated that the residential buildings in Hong Kong acted as sinks for these four air contaminants on average. The average sink strengths of NO, NO2, SO2 and O3 were 3.01, 0.42, 0.32 and 1.39 mg/h respectively. The deposition velocity of ozone onto wall surfaces in the buildings was estimated to be 0.0225 cm/s. Comparison of the measured data to the newly developed indoor air quality guidance notes in Hong Kong indicated that the nitrogen oxides level needed some concern while the sulphur dioxide and ozone levels were low in the indoor residential environment. (Author)

  6. An approach to represent a combined exposure to air pollution

    Directory of Open Access Journals (Sweden)

    Mieczyslaw Szyszkowicz

    2015-10-01

    Full Text Available Objectives: The objective of this study was to present a technique for estimating the effect of ambient air pollution mix on health outcomes. Material and Methods: We created a technique of indexing air pollution mix as a cause of the increased odds of health problems. As an illustrative example, we analyzed the impact of pollution on the frequency of emergency department (ED visits due to colitis among young patients (age < 15 years, N = 11 110. Our technique involves 2 steps. First, we considered 6 ambient air pollutants (carbon monoxide, nitrogen dioxide, sulphur dioxide, ozone, and 2 measures of particulate matter treating each pollutant as a single exposure. Odds ratios (ORs for ED visits associated with a standard increase (interquartile range – IQR in the pollutants levels were calculated using the case-crossover technique. The ORs and their 95% confidence intervals (95% CIs were also found for lagged exposures (for lags 1–9 days. Second, we defined a Health Air Study Index (HASI to represent the combined impact of the 6 air pollutants. Results: We obtained positive and statistically significant results for individual air pollutants and among them the following estimations: OR = 1.06 (95% CI: 1.02–1.1, NO2 lag 3, IQR = 12.8 ppb, OR = 1.04 (95% CI: 1.01–1.07, SO2 lag 4, IQR = 2.3 ppb, OR = 1.04 (95% CI: 1–1.06, PM lag 3, IQR = 6.2 μg/m3. Among the re-calculated ORs with the HASI values as an exposure, the highest estimated value was OR = 1.37 (95% CI: 1.12–1.68, for 1 unit of the HASI, lag 3. Conclusions: The proposed index (HASI allows to confirm the pattern of associations for lags obtained for individual air pollutants. In the presented example the used index (HASI indicates the strongest relation with the exposure lagged by 3 days.

  7. Monitoring of the contamination of air and ventilating discharges

    International Nuclear Information System (INIS)

    Simple and rapid methods of monitoring of tritium compounds concentration in the air are suggested. The methods are based on deposition of T-compound aerosols on filters with subsequent chemical or thermal decomposition of selected samples and measurement of the released tritium by ionization method. Moreover, the quantitative determination of the selected sample activity is performed by bremsstrahlung created by tritium β-particles. The apparatus and the measuring procedure are described. The methods for measurement result processing, sensitivity and errors are considered

  8. Proposed Identification of Environmental Tobacco Smoke as a Toxic Air Contaminant

    OpenAIRE

    California Environmental Protection Agency: Air Resources Board

    2005-01-01

    This report provides a comprehensive assessment of the effects of environmental tobacco smoke (secondhand smoke) as of mid-2005 produced by the California Air Resources Board and Office of Environmental Health Hazard Assessment as part of the process of identifying ETS as a toxic air contaminant. Part A of the report includes information about the chemical composition of secondhand smoke and exposure of the public to secondhand smoke, including outdoor exposures. Part B of t...

  9. Carbapenem-Resistant Acinetobacter baumannii: Concomitant Contamination of Air and Environmental Surfaces.

    Science.gov (United States)

    Shimose, Luis A; Masuda, Eriko; Sfeir, Maroun; Berbel Caban, Ana; Bueno, Maria X; dePascale, Dennise; Spychala, Caressa N; Cleary, Timothy; Namias, Nicholas; Kett, Daniel H; Doi, Yohei; Munoz-Price, L Silvia

    2016-07-01

    OBJECTIVE To concomitantly determine the differential degrees of air and environmental contamination by Acinetobacter baumannii based on anatomic source of colonization and type of ICU layout (single-occupancy vs open layout). DESIGN Longitudinal prospective surveillance study of air and environmental surfaces in patient rooms. SETTING A 1,500-bed public teaching hospital in Miami, Florida. PATIENTS Consecutive A. baumannii-colonized patients admitted to our ICUs between October 2013 and February 2014. METHODS Air and environmental surfaces of the rooms of A. baumannii-colonized patients were sampled daily for up to 10 days. Pulsed-field gel electrophoresis (PFGE) was used to type and match the matching air, environmental, and clinical A. baumannii isolates. RESULTS A total of 25 A. baumannii-colonized patients were identified during the study period; 17 were colonized in the respiratory tract and 8 were colonized in the rectum. In rooms with rectally colonized patients, 38.3% of air samples were positive for A. baumannii; in rooms of patients with respiratory colonization, 13.1% of air samples were positive (P=.0001). In rooms with rectally colonized patients, 15.5% of environmental samples were positive for A. baumannii; in rooms of patients with respiratory colonization, 9.5% of environmental samples were positive (P=.02). The rates of air contamination in the open-layout and single-occupancy ICUs were 17.9% and 21.8%, respectively (P=.5). Environmental surfaces were positive in 9.5% of instances in open-layout ICUs versus 13.4% in single-occupancy ICUs (P=.09). CONCLUSIONS Air and environmental surface contaminations were significantly greater among rectally colonized patients; however, ICU layout did not influence the rate of contamination. Infect Control Hosp Epidemiol 2016;37:777-781. PMID:27045768

  10. Effect of Air Pollution, Contamination and High Altitude on Bronchial Asthma

    OpenAIRE

    Nesriene El margoushy*, Mohamad El Nashar**, Hatem Khairy*, Nihad El Nashar*, Hala Mohamad

    2013-01-01

    Epidemiological studies have shown that the prevalence of asthma has risen dramatically worldwide and evidence suggests that environmental factors have an important role in the etiology of the disease. Most respiratory diseases are caused by airborne agents. Our lungs are uniquely vulnerable to contamination from the air we breathe. Air pollution exposure is associated with increased asthma and allergy morbidity and is a suspected contributor to the increasing prevalence of allergic condition...

  11. Distribution of contaminants in buildings by air recirculation and other airflows

    Energy Technology Data Exchange (ETDEWEB)

    Klobut, K.

    1991-01-01

    The computer program was developed for simultaneous dynamic simulation of contaminant concentrations, pressure distribution, air flows and temperatures in multizone buildings. Physical coupling existing between thermal behaviour of building structure and interzonal air movements has an impact on the distribution of contaminants in building. Consideration of this coupling in the calculation method used in the program is a considerable improvement when compared to other hitherto published programs of the same field. The source code is written in Fortran 77. The program is designed to work on an IBM compatible microcomputer. Network model was used for simulation of a building. Using extracts from the program SMOV the procedure was developed for calculating the pressure distribution in the network and resulting one-way air flows. Two-way air flows through large openings were calculated according to the method used earlier in the program MULTIC. The procedure for calculating the temperatures was developed using the thermal model of a room presented earlier in literature. An estimation of the temperature gradient in the room was enabled by permitting the room air to be theoretically divided into vertically stacked zones. The reliability of the program was tested in a number of validation cases and very good agreement was obtained between the simulation results and comparison data. An example building was used in simulations. The dynamic distributions of contaminant concentrations in the building were determined in several setups of positions of doors, with and without the return air and with different thermal loads.

  12. Assessment of the bacterial contamination of hand air dryer in washrooms.

    Science.gov (United States)

    Alharbi, Sulaiman Ali; Salmen, Saleh Hussein; Chinnathambi, Arunachalam; Alharbi, Naiyf S; Zayed, M E; Al-Johny, Bassam O; Wainwright, Milton

    2016-03-01

    The present study was carried out, using standard techniques, to identify and count the bacterial contamination of hand air dryers, used in washrooms. Bacteria were isolated from the air flow, outlet nozzle of warm air dryers in fifteen air dryers used in these washrooms. Bacteria were found to be relatively numerous in the air flows. Bacterially contaminated air was found to be emitted whenever a warm air dryer was running, even when not being used for hand drying. Our investigation shows that Staphylococcus haemolyticus, Micrococcus luteus, Pseudomonas alcaligenes, Bacillus cereus and Brevundimonad diminuta/vesicularis were emitted from all of the dryers sampled, with 95% showing evidence of the presence of the potential pathogen S. haemolyticus. It is concluded that hot air dryers can deposit pathogenic bacteria onto the hands and body of users. Bacteria are distributed into the general environment whenever dryers are running and could be inhaled by users and none-users alike. The results provide an evidence base for the development and enhancement of hygienic hand drying practices. PMID:26981009

  13. Air-Seawater Exchange of Organochlorine Pesticides along the Sediment Plume of a Large Contaminated River.

    Science.gov (United States)

    Lin, Tian; Guo, Zhigang; Li, Yuanyuan; Nizzetto, Luca; Ma, Chuanliang; Chen, Yingjun

    2015-05-01

    Gaseous exchange fluxes of organochlorine pesticides (OCPs) across the air-water interface of the coastal East China Sea were determined in order to assess whether the contaminated plume of the Yangtze River could be an important regional source of OCPs to the atmosphere. Hexachlorocyclohexanes (HCHs), chlordane compounds (CHLs), and dichlorodiphenyltrichloroethanes (DDTs) were the most frequently detected OCPs in air and water. Air-water exchange was mainly characterized by net volatilization for all measured OCPs. The net gaseous exchange flux ranged 10-240 ng/(m2·day) for γ-HCH, 60-370 ng/(m2·day) for trans-CHL, 97-410 ng/(m2·day) for cis-CHL, and ∼0 (e.g., equilibrium) to 490 ng/(m2·day) for p,p'-DDE. We found that the plume of the large contaminated river can serve as a significant regional secondary atmospheric source of legacy contaminants released in the catchment. In particular, the sediment plume represented the relevant source of DDT compounds (especially p,p'-DDE) sustaining net degassing when clean air masses from the open ocean reached the plume area. In contrast, a mass balance showed that, for HCHs, contaminated river discharge (water and sediment) plumes were capable of sustaining volatilization throughout the year. These results demonstrate the inconsistencies in the fate of HCHs and DDTs in this large estuarine system with declining primary sources. PMID:25827140

  14. Environmental contaminants in golden shiners from Picnic Pond, U.S. Naval Air Station, Brunswick, Maine

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — On July 25, 1995, the U.S. Fish and Wildlife Service conducted a contaminant survey of fish from Picnic Pond on the U.S. Naval Air Station in Brunswick, Maine...

  15. (Environmental investigation of ground water contamination at Wright-Patterson Air Force Base, Ohio)

    Energy Technology Data Exchange (ETDEWEB)

    1992-03-01

    This report presents information related to the sampling of ground water at the Wright-Patterson Air Force Base. It is part of an investigation into possible ground water contamination. Information concerns well drilling/construction; x-ray diffraction and sampling; soil boring logs; and chain-of-custody records.

  16. Hazard Assessment of Chemical Air Contaminants Measured in Residences

    Energy Technology Data Exchange (ETDEWEB)

    Logue, J.M.; McKone, T.E.; Sherman, M. H.; Singer, B.C.

    2010-05-10

    Identifying air pollutants that pose a potential hazard indoors can facilitate exposure mitigation. In this study, we compiled summary results from 77 published studies reporting measurements of chemical pollutants in residences in the United States and in countries with similar lifestyles. These data were used to calculate representative mid-range and upper bound concentrations relevant to chronic exposures for 267 pollutants and representative peak concentrations relevant to acute exposures for 5 activity-associated pollutants. Representative concentrations are compared to available chronic and acute health standards for 97 pollutants. Fifteen pollutants appear to exceed chronic health standards in a large fraction of homes. Nine other pollutants are identified as potential chronic health hazards in a substantial minority of homes and an additional nine are identified as potential hazards in a very small percentage of homes. Nine pollutants are identified as priority hazards based on the robustness of measured concentration data and the fraction of residences that appear to be impacted: acetaldehyde; acrolein; benzene; 1,3-butadiene; 1,4-dichlorobenzene; formaldehyde; naphthalene; nitrogen dioxide; and PM{sub 2.5}. Activity-based emissions are shown to pose potential acute health hazards for PM{sub 2.5}, formaldehyde, CO, chloroform, and NO{sub 2}.

  17. Hazard Assessment of Chemical Air Contaminants Measured in Residences

    International Nuclear Information System (INIS)

    Identifying air pollutants that pose a potential hazard indoors can facilitate exposure mitigation. In this study, we compiled summary results from 77 published studies reporting measurements of chemical pollutants in residences in the United States and in countries with similar lifestyles. These data were used to calculate representative mid-range and upper bound concentrations relevant to chronic exposures for 267 pollutants and representative peak concentrations relevant to acute exposures for 5 activity-associated pollutants. Representative concentrations are compared to available chronic and acute health standards for 97 pollutants. Fifteen pollutants appear to exceed chronic health standards in a large fraction of homes. Nine other pollutants are identified as potential chronic health hazards in a substantial minority of homes and an additional nine are identified as potential hazards in a very small percentage of homes. Nine pollutants are identified as priority hazards based on the robustness of measured concentration data and the fraction of residences that appear to be impacted: acetaldehyde; acrolein; benzene; 1,3-butadiene; 1,4-dichlorobenzene; formaldehyde; naphthalene; nitrogen dioxide; and PM2.5. Activity-based emissions are shown to pose potential acute health hazards for PM2.5, formaldehyde, CO, chloroform, and NO2.

  18. Temporal variability of combined sewer overflow contaminants: evaluation of wastewater micropollutants as tracers of fecal contamination.

    Science.gov (United States)

    Madoux-Humery, Anne-Sophie; Dorner, Sarah; Sauvé, Sébastien; Aboulfadl, Khadija; Galarneau, Martine; Servais, Pierre; Prévost, Michèle

    2013-09-01

    A monitoring program was initiated for two sewage outfalls (OA and OB) with different land uses (mainly residential versus institutional) over the course of a year. Eleven CSO events resulting from fall and summer precipitations and a mixture of snowmelt and precipitation in late winter and early spring were monitored. Median concentrations measured in CSOs were 1.5 × 10(6)Escherichia coli/100 mL, 136.0 mg/L of Total Suspended Solids (TSS), 4599.0 ng/L of caffeine (CAF), 158.9 ng/L of carbamazepine (CBZ), in outfall OA and 5.1 × 10(4)E. coli/100 mL, 167.0 mg TSS/L, 300.8 ng CAF/L, 4.1 ng CBZ/L, in outfall OB. Concentration dynamics in CSOs were mostly related to the dilution by stormwater and the time of day of the onset of overflows. Snowmelt was identified as a critical period with regards to the protection of drinking water sources given the high contaminant concentrations and long duration of events in addition to a lack of restrictions on overflows during this period. Correlations among measured parameters reflected the origins and transport pathways of the contaminants, with E. coli being correlated with CBZ. TSS were not correlated with E. coli because E. coli was found to be mostly associated with raw sewage whereas TSS were additionally from the resuspension of in-sewer deposits and surface runoff. In receiving waters, E. coli remained the best indicator of fecal contamination in strongly diluted water samples as compared to WWMPs because WWMPs can be diluted to below their detection limits. PMID:23764588

  19. Gravel washing demonstration system and reducing the contaminated soil by BAT (Blend Air Tornado pump)

    International Nuclear Information System (INIS)

    Gravel washing system is composed of Blend Air Tornado pump (BAT), gravel classification and muddy water purification equipments. Gravel contaminated by radioactive cesium, pure water and air are mixed in BAT. This process will wash the contaminated gravel and reduce its radioactivity quickly. BAT is operated under appropriate water pressure and air/water/solid gravel ratio. After washing the gravel, it is classified by grain gravel classification equipment and the muddy waste water is purified by cohesive material process. This process is simple and reasonable gravel washing system. Improvement of the existing technology and the maintenance management in easy operation and a small number of people are possible for the system. The system is demonstrated to be the high efficiency decontamination technology of radioactive cesium on soils such as gravel with energy saving system which does not give the load on the environment. (author)

  20. Effect of Air Stability on the Dispersal of Exhaled Contaminant in Rooms

    DEFF Research Database (Denmark)

    Xu, Chunwen; Gong, Guangcai; Nielsen, Peter V.;

    2013-01-01

    Experiments are conducted in a full-scale chamber equipped with whole floor and whole ceiling supply or exhaust to form approximately zero and larger temperature gradients corresponding to unstable and stable air conditions. It can be observed that the air with smoke exhaled from a life-sized the......Experiments are conducted in a full-scale chamber equipped with whole floor and whole ceiling supply or exhaust to form approximately zero and larger temperature gradients corresponding to unstable and stable air conditions. It can be observed that the air with smoke exhaled from a life...... the manikin, indicating that the person who exhales the contaminant may not be polluted by himself as the protective effect of the thermal boundary layer around the body, especially in stable condition with two concentration zones and clean air drawn from the inlets. However, other persons facing the...

  1. Air bottoming cycle, an alternative to combined cycles. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Kaikko, J. [Royal Inst. of Techn., Stockholm (Sweden). Dept. of Energy Technology

    2001-10-01

    In this work, the idea of Air Bottoming Cycle (ABC) has been studied. The objectives for the work have been to establish an understanding of the concept for power and heat generation as well as to find - if possible - feasible concepts for future use in the Swedish energy system. Combined cycle in power generation is an established technology. In the conventional combined cycle, a gas turbine works as a topping cycle together with the steam (Rankine) bottoming cycle. In the ABC the steam bottoming cycle is replaced with a gas turbine (Brayton) bottoming cycle having air as a working fluid. The two gas turbines are thermally connected over a gas-to-gas heat exchanger. This concept promises savings in weight and cost, as well as operating benefits, compared to the Rankine bottoming technology. The ABC has been modelled using a heat balance program, and a parametric study for the concept optimisation as well as for off-design analysis has been performed. Performance of the ABC has been compared to other, established technologies. A preliminary economic evaluation has been made. As a result of the study, it is clarified that the Rankine bottoming cycle with steam remains superior to the ABC as regards electrical efficiency in the medium and large power scale. For small-scale applications (<10 MW{sub e}) where the thermodynamic advantage of the Rankine cycle is not dominating any longer and its economy is burdened by the heavy investment structure, the ABC becomes the better alternative for energy utilisation. A preliminary economic evaluation shows that (at energy prices autumn 2000) the ABC is at the same level as the comparable small-scale cogeneration installations. Due to high power-to-heat ratio however, higher electricity prices will favour the ABC. One interesting feature of the ABC is that about 50% of the dissipated low-value heat from the cycle is carried by clean (sterile) air at the temperature around 200 deg C. This air can be utilised for space heating or

  2. Air bottoming cycle, an alternative to combined cycles. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Kaikko, J. [Royal Inst. of Tech., Stockholm (Sweden). Dept. of Energy Technology

    2002-02-01

    In this work, the idea of Air Bottoming Cycle (ABC) has been studied. The objectives for the work have been to establish an understanding of the concept for power and heat generation as well as to find - if possible - feasible concepts for future use in the Swedish energy system. Combined cycle in power generation is an established technology. In the conventional combined cycle, a gas turbine works as a topping cycle together with the steam (Rankine) bottoming cycle. In the ABC the steam bottoming cycle is replaced with a gas turbine (Brayton) bottoming cycle having air as a working fluid. The two gas turbines are thermally connected over a gas-to-gas heat exchanger. This concept promises savings in weight and cost, as well as operating benefits, compared to the Rankine bottoming technology. The ABC has been modelled using a heat balance program, and a parametric study for the concept optimisation as well as for off-design analysis has been performed. Performance of the ABC has been compared to other, established technologies. A preliminary economic evaluation has been made. As a result of the study, it is clarified that the Rankine bottoming cycle with steam remains superior to the ABC as regards electrical efficiency in the medium and large power scale. For small-scale applications (<10 MW{sub e}) where the thermodynamic advantage of the Rankine cycle is not dominating any longer and its economy is burdened by the heavy investment structure, the ABC becomes the better alternative for energy utilisation. A preliminary economic evaluation shows that (at energy prices autumn 2000) the ABC is at the same level as the comparable small-scale cogeneration installations. Due to high power-to-heat ratio however, higher electricity prices will favour the ABC. One interesting feature of the ABC is that about 50% of the dissipated low-value heat from the cycle is carried by clean (sterile) air at the temperature around 200 deg C. This air can be utilised for space heating or

  3. Combined Phytotoxicity of Fluorene, Fluoranthrene or Phenanthrene in Anthracene-Contaminated Soil to Crop Seedling Growth

    Directory of Open Access Journals (Sweden)

    Khanitta SOMTRAKOON

    2014-08-01

    Full Text Available The phytotoxicity of different combinations of phenanthrene, fluorene, and fluoranthrene in anthracene-contaminated soil to seedling growth was studied. Seeds of sticky rice and water morning glory were planted in soil contaminated, with anthracene alone, a mixture of anthracene with each polycyclic aromatic hydrocarbon (PAH, and various combinations of PAHs. The results showed that anthracene + fluorene and anthracene + fluoranthene were more toxic to the growth of sticky rice seedlings than anthracene alone or anthracene + phenanthrene. However, all combinations of anthracene with other PAHs were toxic to water morning glory seedlings. When there were 3 - 4 PAHs present together, anthracene + fluoranthene + fluorene was the most toxic combination for shoot length, root length, and fresh weight of both plants, but not for dry weight. Responses of dicot and monocot to the toxicity of PAH co-contamination were different when anthracene was present alone or with other PAHs.

  4. Economic damages of ozone air pollution to crops using combined air quality and GIS modelling

    Science.gov (United States)

    Vlachokostas, Ch.; Nastis, S. A.; Achillas, Ch.; Kalogeropoulos, K.; Karmiris, I.; Moussiopoulos, N.; Chourdakis, E.; Banias, G.; Limperi, N.

    2010-09-01

    This study aims at presenting a combined air quality and GIS modelling methodological approach in order to estimate crop damages from photochemical air pollution, depict their spatial resolution and assess the order of magnitude regarding the corresponding economic damages. The analysis is conducted within the Greater Thessaloniki Area, Greece, a Mediterranean territory which is characterised by high levels of photochemical air pollution and considerable agricultural activity. Ozone concentration fields for 2002 and for specific emission reduction scenarios for the year 2010 were estimated with the Ozone Fine Structure model in the area under consideration. Total economic damage to crops turns out to be significant and estimated to be approximately 43 M€ for the reference year. Production of cotton presents the highest economic loss, which is over 16 M€, followed by table tomato (9 M€), rice (4.2 M€), wheat (4 M€) and oilseed rape (2.8 M€) cultivations. Losses are not spread uniformly among farmers and the major losses occur in areas with valuable ozone-sensitive crops. The results are very useful for highlighting the magnitude of the total economic impacts of photochemical air pollution to the area's agricultural sector and can potentially be used for comparison with studies worldwide. Furthermore, spatial analysis of the economic damage could be of importance for governmental authorities and decision makers since it provides an indicative insight, especially if the economic instruments such as financial incentives or state subsidies to farmers are considered.

  5. Combined filtering facilities for nuclear air cleaning systems

    International Nuclear Information System (INIS)

    Full text of publication follows: The choice of an optimal cleaning technology and cleaning system design depends on the specificity of the provision of the ecological safety of NPP under operation and accident conditions. The major requirements imposed on such systems are to achieve high efficiency (99,0-99,95 %) and reliability. In this respect, the important problem is to develop combined filtering facilities (CFF) which are able within the same aggregate to provide complex cleaning of air from moisture, radioactive aerosols, iodine in molecular (I2) and organic (CH3I) forms. A great experience accumulated at SSC RF IPPE and other organizations in the course of researches dealing with construction of aerosol filters and iodine filters-sorbers for NPPs and radio-chemical plants made it possible to develop a pilot mock-up facility providing complex cleaning of air from radioactive aerosols and iodine in reference to the real ventilation conditions at the First in the World Nuclear Power Plant. By now complex tests of the mock-up specimen of the UFK-3500 facility have been run with the aim of determining the functional efficiency of its separate filtering sections in terms of droplet moisture, atmospheric and radioactive aerosols and radioiodine and its organic compounds as well as of the filtering facility as a whole. Control over aerosol and radioiodine concentrations and volumetric activity was performed using laser and gamma spectrometry. The obtained data give necessary grounds to formulate the recommendations, how to develop and organize production of combined filtering facilities for flow rates of the medium to be cleaned of 3500, 7000, 10500 m3/h. The production is organized on the basis of OAO PZ 'Signal' in Obninsk. Provision is made for using small capacity small size filters (for radiochemical plants and research test facilities and rigs) and high efficiency sorbers (for commercial NPP) as filters-sorbers. To date the design plans and specifications

  6. Effects on inhaled uranium mine air contaminants in beagle dogs

    International Nuclear Information System (INIS)

    The high incidence of lung cancer among uranium miners of the Colorado plateau is a matter of national concern in a period of increasing demand for uranium ore. These miners are exposed to a variety of inhalation hazards, including radon daughters, uranium ore dust, and cigarette smoking, that may cause or contribute to respiratory tract pathology. Over 98 percent of the miners developing lung cancer have had histories of cigarette smoking. In order to determine the combined or separate roles of radon daughters and cigarette smoking in the development of lung cancer and other respiratory tract pathology, groups of 20 dogs each received daily life span exposures to 4 hours of 600 working levels of radon daughters with ore dust, and/or cigarette smoking over 16 hours per day, 7 days per week, or both; control dogs received sham smoking. After 4 years of exposure, respiratory tract pathology included macrophage accumulation, septal fibrosis, epithelial hyperplasia, endothelial proliferation, vesicular and bullous emphysema, and extensive epithelial changes involving squamous metaplasia with atypical nuclei. These effects were primarily related to exposure to radon daughters and uranium ore dust, with and without cigarette smoke

  7. Mitigation of trichloroethylene contaminated air streams through biofiltration: a pilot-scale study

    International Nuclear Information System (INIS)

    As a result of abundant usage and improper disposal practices, trichloroethylene (TCE) is one of the most prevalent groundwater contaminants. Traditional cleanup methods of aquifers contaminated with TCE include pumping the water to the surface and treating with stripper technology, soil vapor extraction, and air sparging. As a result of each of these mitigation schemes, TCE is transferred from the aqueous to the gas phase. As regulations associated with air emission tighten, development of technologies both technically feasible and cost effective for remediating TCE laden gas streams becomes imperative. This project demonstrated the use of biofiltration technology to mitigate TCE contaminated air streams. A pilot-scale biofilter system was designed, constructed, and subsequently installed at the Anniston Army Depot (ANAD), Anniston, AL. The system was inoculated with a propane-oxidizing microbial consortium that had previously been shown to degrade TCE as well as other short-chained chlorinated aliphatics and a variety of one-and two-ring aromatic compounds. Critical process variables were identified and their effects on system performance analyzed. Results indicated that the process scheme used to introduce propane into the biofiltration system had a significant impact on the observed TCE removal efficiency. The inlet contaminant concentration as well as the loading rate also had an impact on observed TCE degradation rates. Results suggest that biofilter performance and economics are generally improved by manipulating a specific waste stream so as to increase the TCE concentration and decrease the volumetric flow rate of the contaminated air fed to the biofilter. Through manipulation of process variables, including the empty bed contact time, TCE degradation efficiencies greater than 99.9 percent were sustained. No microbial inhibition was observed at inlet TCE concentrations as high as 87 parts per million on a volume basis (ppmv). (author)

  8. Characterization of the frequency and nature of bleed air contamination events in commercial aircraft.

    Science.gov (United States)

    Shehadi, M; Jones, B; Hosni, M

    2016-06-01

    Contamination of the bleed air used to pressurize and ventilate aircraft cabins is of concern due to the potential health and safety hazards for passengers and crew. Databases from the Federal Aviation Administration, NASA, and other sources were examined in detail to determine the frequency of bleed air contamination incidents. The frequency was examined on an aircraft model basis with the intent of identifying aircraft make and models with elevated frequencies of contamination events. The reported results herein may help investigators to focus future studies of bleed air contamination incidents on smaller number of aircrafts. Incident frequency was normalized by the number of aircraft, number of flights, and flight hours for each model to account for the large variations in the number of aircraft of different models. The focus of the study was on aircraft models that are currently in service and are used by major airlines in the United States. Incidents examined in this study include those related to smoke, oil odors, fumes, and any symptom that might be related to exposure to such contamination, reported by crew members, between 2007 and 2012, for US-based carriers for domestic flights and all international flights that either originated or terminated in the US. In addition to the reported frequency of incidents for different aircraft models, the analysis attempted to identify propulsion engines and auxiliary power units associated with aircrafts that had higher frequencies of incidents. While substantial variations were found in frequency of incidents, it was found that the contamination events were widely distributed across nearly all common models of aircraft. PMID:25864418

  9. Distribution of Exhaled Contaminants and Personal Exposure in a Room using Three Different Air Distribution Strategies

    DEFF Research Database (Denmark)

    Olmedo, Inés; Nielsen, Peter V.; Adana, M. Ruiz de;

    2012-01-01

    The level of exposure to human exhaled contaminants in a room depends not only on the air distribution system but also on people’s different positions, the distance between them, people’s activity level and height, direction of exhalation, and the surrounding temperature and temperature gradient....... Human exhalation is studied in detail for different distribution systems: displacement and mixing ventilation as well as a system without mechanical ventilation. Two thermal manikins breathing through the mouth are used to simulate the exposure to human exhaled contaminants. The position and distance...

  10. Forest fires in Eastern countries: air contamination measurements by the IRSN. Information file

    International Nuclear Information System (INIS)

    Forest fires sparking of in contaminated territories of Bielorussia, Ukraine and Western Russia can lead to transfrontier contamination in particular in Western Europe. Such radiological events with 137Cs peaks were recorded in France in 2002 (weeks 35 and 37) by the OPERA-Air network of the French Institute of Radiation Protection and Nuclear Safety (IRSN). These rises of 137Cs activity can be recorded only when France is under the influence of winds coming from the E-NE. The activity levels of such events is of the order of maximum 1.5 μBq/m3 and cannot represent any threat for the populations' health. (J.S.)

  11. Storage of LWR spent fuel in air. Volume 3, Results from exposure of spent fuel to fluorine-contaminated air

    International Nuclear Information System (INIS)

    The Behavior of Spent Fuel in Storage (BSFS) Project has conducted research to develop data on spent nuclear fuel (irradiated U02) that could be used to support design, licensing, and operation of dry storage installations. Test Series B conducted by the BSFS Project was designed as a long-term study of the oxidation of spent fuel exposed to air. It was discovered after the exposures were completed in September 1990 that the test specimens had been exposed to an atmosphere of bottled air contaminated with an unknown quantity of fluorine. This exposure resulted in the test specimens reacting with both the oxygen and the fluorine in the oven atmospheres. The apparent source of the fluorine was gamma radiation-induced chemical decomposition of the fluoro-elastomer gaskets used to seal the oven doors. This chemical decomposition apparently released hydrofluoric acid (HF) vapor into the oven atmospheres. Because the Test Series B specimens were exposed to a fluorine-contaminated oven atmosphere and reacted with the fluorine, it is recommended that the Test Series B data not be used to develop time-temperature limits for exposure of spent nuclear fuel to air. This report has been prepared to document Test Series B and present the collected data and observations

  12. Subsurface sediment contamination during borehole drilling with an air-actuated down-hole hammer

    Science.gov (United States)

    Malard, Florian; Datry, Thibault; Gibert, Janine

    2005-10-01

    Drilling methods can severely alter physical, chemical, and biological properties of aquifers, thereby influencing the reliability of water samples collected from groundwater monitoring wells. Because of their fast drilling rate, air-actuated hammers are increasingly used for the installation of groundwater monitoring wells in unconsolidated sediments. However, oil entrained in the air stream to lubricate the hammer-actuating device can contaminate subsurface sediments. Concentrations of total hydrocarbons, heavy metals (Cu, Ni, Cr, Zn, Pb, and Cd), and nutrients (particulate organic carbon, nitrogen, and phosphorus) were measured in continuous sediment cores recovered during the completion of a 26-m deep borehole drilled with a down-hole hammer in glaciofluvial deposits. Total hydrocarbons, Cu, Ni, Cr and particulate organic carbon (POC) were all measured at concentrations far exceeding background levels in most sediment cores. Hydrocarbon concentration averaged 124 ± 118 mg kg - 1 dry sediment ( n = 78 samples) with peaks at depths of 8, 14, and 20 m below the soil surface (maximum concentration: 606 mg kg - 1 ). The concentrations of hydrocarbons, Cu, Ni, Cr, and POC were positively correlated and exhibited a highly irregular vertical pattern, that probably reflected variations in air loss within glaciofluvial deposits during drilling. Because the penetration of contaminated air into the formation is unpreventable, the representativeness of groundwater samples collected may be questioned. It is concluded that air percussion drilling has strong limitations for well installation in groundwater quality monitoring surveys.

  13. (Environmental investigation of ground water contamination at Wright- Patterson Air Force Base, Ohio)

    Energy Technology Data Exchange (ETDEWEB)

    1991-10-01

    This Health and Safety Plan (HSP) was developed for the Environmental Investigation of Ground-water Contamination Investigation at Wright-Patterson Air Force Base near Dayton, Ohio, based on the projected scope of work for the Phase 1, Task 4 Field Investigation. The HSP describes hazards that may be encountered during the investigation, assesses the hazards, and indicates what type of personal protective equipment is to be used for each task performed. The HSP also addresses the medical monitoring program, decontamination procedures, air monitoring, training, site control, accident prevention, and emergency response.

  14. A tracer method for quantifying contamination of building supply air: reentrainment of laboratory hood exhausts.

    Science.gov (United States)

    Barnett, J L; Richard, M L; Rose, V E

    1983-08-01

    A method is described for quantifying the reentrainment of exhaust air contaminants into a building's fresh-air supply system. The method relies on the "tracer" gas, sulfur hexafluoride (SF6), which Is detected by infrared (IR) absorption analysis. This method of analysis differs from the conventional gas chromatography, electron capture detection method due to the MIRAN-1 A's portability, direct-reading capabilities, ease of operation and modest cost. Specific instrument settings for the MIRAN-1 A are given such that detection of SF6 will be optimized without interference. Calculations for quantifying reentrainment are presented and discussed for the "worst case" reentrainment observed. PMID:6624644

  15. Extract and cleaning of contaminated air in commercial kitchens : Ultraviolet technology

    OpenAIRE

    Alexandrova, Alevtina

    2009-01-01

    The subject of the project was a research about cleaning of contaminated air in commercial kitchens. Kitchen hoods must be cleaned from heat, moisture, smoke, and vaporized grease all the time. Accumulations of grease on kitchen equipment can easily be the reason of fire. The thesis presents literature review of various sources like books, reports, and Internet articles. Most of the articles and tests were maid by research institutes or big manufacture companies connected with ventilation ...

  16. Elements of a unified prognostic model for secondary air contamination by resuspension

    International Nuclear Information System (INIS)

    Based on results of several joint experimental campaigns and an extensive literature survey, a prognostic model was constructed capable of predicting airborne activity concentrations and size distributions as well as soil surface activity concentrations as a function of time and meteorological conditions. Example scenario calculations show that agricultural practices are of lesser importance to secondary air contamination than dust storms immediately after primary deposition and forest fires

  17. The air contamination by 137Cs and 7Be in the territory of Slovak Republic

    International Nuclear Information System (INIS)

    This report presents the results from measurements of aerosols of samples collected on the Measuring Points of Air Contamination. The activity concentrations of 137Cs and 7Be in air during years 1993-1996 and the annual committed effective doses due to inhalation are summarized. During that period the concentrations of 137Cs in air varied between 0.4 and 13.8 μBq m-3. The annual committed effective doses due to inhalation of 137Cs in air, according to the age, varied between 0.02 and 0.22 nSv from March 1993 through December 1996. During that period the concentrations of Be in air varied between 1.0 and 7.7 mBq m-3 with an annual average of 2.8 mBq m-3. Highest concentrations of 7Be in air were usually noted during the summer period. The annual committed effective doses due to inhalation of 7Be in air varied, according to age, from 1.1 to 1.8 nSv. (authors)

  18. Microbial Air Contamination in Indoor and Outdoor Environment of Pig Farms

    Directory of Open Access Journals (Sweden)

    Silvana Popescu

    2014-05-01

    Full Text Available Ensuring a good air quality in pig farms is important for the health of animals and human workers. The aim of this study was the assessment of the microbiological quality of the air inside the pig houses and outside of these. The study was accomplished in two pig-fattening farms in Cluj County. The microbiological air quality was assessed in the cold and warm season, by determination of the total counts of mesophilic bacteria, staphylococci, streptococci, gram-negative bacteria and fungi. The bacterial and fungal counts varied in the air of the investigated farms. In relation to the season the mean counts of bacteria and fungi were significantly higher (P < 0.05 in the cold season. No significant differences (P > 0.05 were found between the values of the parameters determined from the indoor air and those obtained outside, from a distance of 5 m from the pig houses. The numbers of the bacteria and fungi in the outdoor air lowered as the distance from the farms increased, the differences being significant at 25 and 50 m (P < 0.05. The results of the study show a high bacterial contamination of the indoor and outdoor air of the pig farms.

  19. Investigation of remediation of soil contaminated with diesel fuel using air venting

    International Nuclear Information System (INIS)

    Soil venting is an effective and widely used method to remediate hydrocarbonically contaminated soils. A non-isothermal model, proposed by Lingineni and Dhir (1992) to predict evaporation rates of organic contaminants in an unsaturated non-sorbing soil, was incorporated into a computer code capable of numerically analyzing multi-component diesel fuel. The program accounts for 14 major components of diesel fuel as well as for temperature variation due to evaporation of the contaminant, preheating of the venting air, and heat loss. Experiments to verify the model performance were conducted in a one-dimensional column. Temperature readings from thermocouples located in the test section were recorded during the experiment and the composition of hydrocarbons in the effluent air was also monitored. The effluent gas samples were extracted at the selected times and analyzed with the help of a gas chromatograph. The experimental temperature readings and vapor composition in the extracted samples are in general agreement with the predictions from the computer program. The results show that the diesel components are removed according to their volatility with the higher volatility components being removed first. It is also found that preheating of the venting air can significantly increase the removal rates of the components

  20. Online optimal control of variable refrigerant flow and variable air volume combined air conditioning system for energy saving

    International Nuclear Information System (INIS)

    The variable refrigerant flow (VRF) and variable air volume (VAV) combined air conditioning system can solve the problem of the VRF system in outdoor air ventilation while taking advantage of its high part load energy efficiency. Energy performance of the combined air conditioning system can also be optimized by joint control of both the VRF and the VAV parts. A model-based online optimal control strategy for the combined air conditioning system is presented. Simplified adaptive models of major components of the combined air conditioning system are firstly developed for predicting system performances. And a cost function in terms of energy consumption and thermal comfort is constructed. Genetic algorithm is used to search for the optimal control sets. The optimal control strategy is tested and evaluated through two case studies based on the simulation platform. Results show that the optimal strategy can effectively reduce energy consumption of the combined air conditioning system while maintaining acceptable thermal comfort. - Highlights: • A VRF and VAV combined system is proposed. • A model-based online optimal control strategy is proposed for the combined system. • The strategy can reduce energy consumption without sacrificing thermal comfort. • Novel simplified adaptive models are firstly developed for the VRF system

  1. Electroremediation of PCB contaminated soil combined with iron nanoparticles: Effect of the soil type

    DEFF Research Database (Denmark)

    Gomes, Helena I.; Dias-Ferreira, Celia; Ottosen, Lisbeth M.;

    2015-01-01

    valent iron particles in a two-compartment cell is tested and compared to a more conventional combination of electrokinetic remediation and nZVI in a three-compartment cell. In the new two-compartment cell, the soil is suspended and stirred simultaneously with the addition of zero valent iron......Polychlorinated biphenyls (PCB) are carcinogenic and persistent organic pollutants that accumulate in soils and sediments. Currently, there is no cost-effective and sustainable remediation technology for these contaminants. In this work, a new combination of electrodialytic remediation and zero...... nanoparticles. Remediation experiments are made with two different historically PCB contaminated soils, which differ in both soil composition and contamination source. Soil 1 is a mix of soils with spills of transformer oils, while Soil 2 is a superficial soil from a decommissioned school where PCB were used as...

  2. Electroremediation of PCB contaminated soil combined with iron nanoparticles: Effect of the soil type

    OpenAIRE

    Gomes, Helena I.; Dias-Ferreira, Celia; Ottosen, Lisbeth M.; Ribeiro, Alexandra B.

    2015-01-01

    Polychlorinated biphenyls (PCB) are carcinogenic and persistent organic pollutants that accumulate in soils and sediments. Currently, there is no cost-effective and sustainable remediation technology for these contaminants. In this work, a new combination of electrodialytic remediation and zero valent iron particles in a two-compartment cell is tested and compared to a more conventional combination of electrokinetic remediation and nZVI in a three-compartment cell. In the new two-compartment ...

  3. PCB in the air during landfilling of a contaminated lake sediment

    Science.gov (United States)

    Bremle, G.; Larsson, P.

    We studied PCB concentration in the air during the build-up of a landfill of PCB-contaminated sediment. A small lake was remediated and the sediment (150 000 m 3 containing about 400 kg PCB) deposited in a nearby landfill. PCB concentration in the air was elevated during landfilling and the extent was determined by the amount of sediment handled and the temperature. The air was enriched in more volatile PCB congeners compared to the deposited sediment, suggesting volatilization as the major transport process in addition to particle transport. The PCB concentration in air showed an exponential decline with distance from the centre of the landfill, with a one order of magnitude decrease 350 m from the centre. At a distance of 850 m from the centre about 5% of the elevated PCB level remained, which was significantly higher when compared to the reference concentration (15 km from the landfill). The PCB congener pattern changed gradually from the landfill centre to the reference. After the landfill was closed and the contaminated, dewatered sediment covered by uncontaminated soil, PCB levels and pattern were similar to that of the reference.

  4. Effects of contaminants on reproductive success of aquatic birds nesting at Edwards Air Force Base, California.

    Science.gov (United States)

    Hothem, R L; Crayon, J J; Law, M A

    2006-11-01

    Contamination by organochlorine pesticides (OCs), polychlorinated biphenyls, metals, and trace elements at Edwards Air Force Base (EAFB), located in the Mojave Desert, could adversely affect nesting aquatic birds, especially at the sewage lagoons that comprise Piute Ponds. Estimates of avian reproduction, in conjunction with analyses of eggs and avian foods for contaminant residues, may indicate the potential for negative effects on avian populations. From 1996 to 1999, we conducted studies at the Piute Ponds area of EAFB to evaluate the impacts of contaminants on nesting birds. Avian reproduction was evaluated in 1999. Eggs were collected for chemical analyses in 1996 and 1999, and African clawed frogs (Xenopus laevis), a likely food source, were collected for chemical analyses in 1998. Avian species occupying the higher trophic levels--black-crowned night-heron (Nycticorax nycticorax), white-faced ibis (Plegadis chihi), and American avocet (Recurvirostra americana)--generally bioaccumulated higher concentrations of contaminants in their eggs. Reproductive success and egg hatchability of night-herons and white-faced ibises in the Piute Ponds were similar to results observed at other western colonies. Deformities were observed in only one embryo in this study, but concentrations of contaminants evaluated in this ibis embryo were considered insufficient to have caused the deformities. Because clawed frogs, a primary prey item for night-herons at Piute Ponds, had no detectable levels of any OCs, it is likely that OCs found in night-heron eggs were acquired from the wintering grounds rather than from EAFB. The presence of isomers of dichlorodiphenyltrichloroethane (DDT) in ibis eggs indicated recent exposure, but invertebrates used for food by ibises were not sampled at Piute Ponds, and conclusions about the source of OCs in ibis eggs could not be made. Concentrations of contaminants in random and failed eggs of individual species were not different, and we concluded

  5. Contamination

    OpenAIRE

    Cundill, A.; J. Bacon; Dale, P; Fordyce, F.M.; Fowler, D; Hedmark, A.; Hern, A.; Skiba, U.

    2011-01-01

    Soil contamination occurs when substances are added to soil, resulting in increases in concentrations above background or reference levels. Pollution may follow from contamination when contaminants are present in amounts that are detrimental to soil quality and become harmful to the environment or human health. Contamination can occur via a range of pathways including direct application to land and indirect application from atmospheric deposition. Contamination was identified b...

  6. Combined cadmium and elevated ozone affect concentrations of cadmium and antioxidant systems in wheat under fully open-air conditions

    International Nuclear Information System (INIS)

    Highlights: ► Combined effect of elevated O3 and Cd levels on wheat was studied using the free-air concentration enrichment system. ► Elevated O3 levels result in an increased concentration of Cd in wheat plants grown on Cd-contaminated soils. ► Combined cadmium and elevated O3 have a significantly synergic effect on oxidative stress in wheat shoots. - Abstract: Pollution of the environment with both ozone (O3) and heavy metals has been steadily increasing. An understanding of their combined effects on plants, especially crops, is limited. Here we studied the effects of elevated O3 on oxidative stress and bioaccumulation of cadmium (Cd) in wheat under Cd stress using a free-air concentration enrichment (FACE) system. In this field experiment in Jiangdu (Jiangsu Province, China), wheat plants were grown in pots containing soil with various concentrations of cadmium (0, 2, and 10 mg kg−1 Cd was added to the soil) under ambient conditions and under elevated O3 levels (50% higher than the ambient O3). Present results showed that elevated O3 led to higher concentrations of Cd in wheat tissues (shoots, husk and grains) with respect to contaminated soil. Combined exposure to Cd and elevated O3 levels strongly affected the antioxidant isoenzymes POD, APX and CAT and accelerated oxidative stress in wheat leaves. Our results suggest that elevated O3 levels cause a reduction in food quality and safety.

  7. Modeling emissions and dispersion of contaminants from cleanup activities at a mixed waste site to estimate air impacts and risks

    International Nuclear Information System (INIS)

    The transport and dispersion of contaminants via the air pathway is a major concern during cleanup of contaminated sites. Impacts to air quality and human health during cleanup were evaluated for the Weldon Spring site by using site-specific information for source areas, activities, and receptor locations. In order to ensure protection of human health and the environment, results are being used to focus on those cleanup activities for which release controls should be emphasized

  8. Remediation of Nitrobenzene Contaminated Soil by Combining Surfactant Enhanced Soil Washing and Effluent Oxidation with Persulfate

    OpenAIRE

    Yan, Jingchun; Gao, Weiguo; Qian, Linbo; Han, Lu; Chen, Yun; Chen, Mengfang

    2015-01-01

    The combination of surfactant enhanced soil washing and degradation of nitrobenzene (NB) in effluent with persulfate was investigated to remediate NB contaminated soil. Aqueous solution of sodium dodecylbenzenesulfonate (SDBS, 24.0 mmol L-1) was used at a given mass ratio of solution to soil (20:1) to extract NB contaminated soil (47.3 mg kg-1), resulting in NB desorption removal efficient of 76.8%. The washing effluent was treated in Fe2+/persulfate and Fe2+/H2O2 systems successively. The de...

  9. Evaluation of a Combined Ultraviolet Photocatalytic Oxidation(UVPCO)/Chemisorbent Air Cleaner for Indoor Air Applications

    Energy Technology Data Exchange (ETDEWEB)

    Hodgson, Alfred T.; Destaillats, Hugo; Hotchi, Toshifumi; Fisk,William J.

    2007-02-01

    acetaldehyde removal efficiency decreased to less than 10% with extended use of the device. The folded bed was considerably more effective; formaldehyde was removed with greater than 90% efficiency, and acetaldehyde was removed at about 70% efficiency. With the combined UVPCO/chemisorbent system, the net removal efficiencies for formaldehyde and acetaldehyde were 90% and 40%, respectively. In summary, the use of a multi-panel, folded scrubber filled with NaMnO{sub 4}{center_dot}H{sub 2}O chemisorbent media downstream of the prototype UVPCO air cleaner effectively counteracted the generation of formaldehyde and acetaldehyde due to incomplete oxidation of VOCs in the UVPCO reactor. Thus, this combined UVPCO air cleaner and chemisorbent system appears to have sufficient VOC removal efficiency to enable a 50 % reduction in ventilation rate without increasing indoor aldehyde concentrations.

  10. Remediation of arsenic contaminated soil by coupling oxalate washing with subsequent ZVI/Air treatment.

    Science.gov (United States)

    Cao, Menghua; Ye, Yuanyao; Chen, Jing; Lu, Xiaohua

    2016-02-01

    The application of a novel coupled process with oxalate washing and subsequent zero-valent iron (ZVI)/Air treatment for remediation of arsenic contaminated soil was investigated in the present study. Oxalate is biodegradable and widely present in the environment. With addition of 0.1 mol L(-1) oxalate under circumneutral condition, 83.7% and 52.6% of arsenic could be removed from a spiked kaolin and an actual contaminated soil respectively. Much more oxalate adsorption on the actual soil was attributed to the higher soil organic matter and clay content. Interestingly, oxalate retained in the washing effluent could act as an organic ligand to promote the oxidation efficiency of ZVI/Air at near neutral pH. Compared with the absence of oxalate, much more As(III) was oxidized. Arsenic was effectively adsorbed on iron (hydr)oxides as the consumption of oxalate and the increase of pH value. For the actual soil washing effluent, about 94.9% of total arsenic was removed after 120 min's treatment without pH adjustment. It has been demonstrated that As(V) was the dominant arsenic speciation adsorbed on iron (hydr)oxides. This study provides a promising alternative for remediation of arsenic contaminated soil in view of its low cost and environmental benign. PMID:26476769

  11. Use of a horizontal air-dispersion system to enhance biodegradation of diesel fuel contaminated soils

    International Nuclear Information System (INIS)

    A horizontal air-dispersion system was designed and installed to enhance the natural biodegradation of residual diesel fuel contaminated soils at an underground storage tank (UST) facility in Seattle, Washington. This system was designed to operate in conjunction with an existing free-product recovery system which exposes more heavily contaminated soils at the capillary fringe to injected air. Results of a pilot study conducted at the facility indicate that an initial biodegradation rate of 2,200 mg of total petroleum hydrocarbons (TPH) per kg of soil per year will be achieved, making in-situ biodegradation a feasible remedial alternative for contaminated site soils. Oxygen, carbon dioxide, and hydrocarbon vapor concentrations have been monitored since full-scale startup in September 1992, using a series of vapor monitoring points (VMPs) installed in the vicinity of the aerated beds and around the perimeter of the facility. Recent monitoring data indicate that the system is capable of aerating soils at distances greater than 80 feet from the aerated beds. Oxygen utilization and carbon dioxide production measured during post-startup respiration tests indicate microbial activity has increased as a result of seven months of full-scale system operation

  12. The importance of determining the air exchange rate in flats and buildings for calculations of the averted indoor inhalation doses arising from contaminated outdoor air

    International Nuclear Information System (INIS)

    The indoor-outdoor air exchange rate is an important parameter when refining estimates of the averted inhaled doses to population in houses and buildings after an emergency event resulting in contamination of outdoor air with a radioactive material. The air exchange rates measured in 70 occupied houses and in 20 unoccupied houses using N2O as the tracer gas are presented, and the results of modelling the averted doses in the residential buildings for both gaseous and aerosol outdoor contaminants are demonstrated. (orig.)

  13. Effect of negative air ions on the potential for bacterial contamination of plastic medical equipment

    Directory of Open Access Journals (Sweden)

    Kerr Kevin G

    2010-04-01

    acrylonitrile, did however develop a positive charge in the presence of the ionizer. Conclusion The findings of the study suggest that the action of negative air ionizers significantly alters the electrostatic landscape of the clinical environment, and that this has the potential to cause any Acinetobacter-bearing particles in the air to be strongly repelled from some plastic surfaces and attracted to others. In so doing, this may prevent critical items of equipment from becoming contaminated with the bacterium.

  14. Possible negative consequences of the secondary air contamination on the quality of accumulated drinking water

    International Nuclear Information System (INIS)

    At the present time when requirements on quality of drinking water are increased, it is necessary not only to put stress on technological processes used in its preparation, but also there is a need to secure that water is distributed even to the consumer in that quality as it leaves a water station. Through a systematic surveillance of water-supply companies within the framework of biological audits it has been found out that the important points in a distribution network where the quality of water is deteriorated are the water reservoirs. Deterioration in quality of accumulated water is jointly caused by elements of technological, constructional and biological nature. The secondary air contamination has a substantial influence on the creation of bio-films on walls and the presence of microorganisms in accumulated drinking water. To this end, a water twin-compartment reservoir has been systematically evaluated during operation, cleaning meantime and before cleaning. The results of hydro-biological and microbiological analysis have confirmed the input of particles and microorganisms through air, their presence in surface level of accumulated water as well as scrapings from accumulation walls. The surveillance considered also the situation without a fixed filter unit, without door lining etc. On fixing a tested filter system into ventilation duct the risk of air contamination was lowered to minimum. (authors)

  15. Tolerance of non-platinum group metals cathodes proton exchange membrane fuel cells to air contaminants

    Science.gov (United States)

    Reshetenko, Tatyana; Serov, Alexey; Artyushkova, Kateryna; Matanovic, Ivana; Sarah Stariha; Atanassov, Plamen

    2016-08-01

    The effects of major airborne contaminants (SO2, NO2 and CO) on the spatial performance of Fe/N/C cathode membrane electrode assemblies were studied using a segmented cell system. The injection of 2-10 ppm SO2 in air stream did not cause any performance decrease and redistribution of local currents due to the lack of stably adsorbed SO2 molecules on Fe-Nx sites, as confirmed by density functional theory (DFT) calculations. The introduction of 5-20 ppm of CO into the air stream also did not affect fuel cell performance. The exposure of Fe/N/C cathodes to 2 and 10 ppm NO2 resulted in performance losses of 30 and 70-75 mV, respectively. DFT results showed that the adsorption energies of NO2 and NO were greater than that of O2, which accounted for the observed voltage decrease and slight current redistribution. The cell performance partially recovered when the NO2 injection was stopped. The long-term operation of the fuel cells resulted in cell performance degradation. XPS analyses of Fe/N/C electrodes revealed that the performance decrease was due to catalyst degradation and ionomer oxidation. The latter was accelerated in the presence of air contaminants. The details of the spatial performance and electrochemical impedance spectroscopy results are presented and discussed.

  16. Detection of the contamination of air by tritiated water vapour around the reactor EL3

    International Nuclear Information System (INIS)

    The authors describe the apparatus used for the detection of the tritiated water vapour contamination in the air around the reactor EL 3. The apparatus consists of two air-circulation ionisation chambers; the air in one of these is dried by passage through a silica-gel column. By carrying out a differential measurement of the ionization currents, it is possible to measure the tritiated water vapour concentration. A theoretical study of the response of the chambers is carried out for two types of emission of the tritiated water vapour: continuous, or in bursts. The experimental work comprises: calibration in the measurement range employed; study of the selectivity for other active gases; study of typical accidents; the interpretation of the results in the case of discontinuous emission, taking into account the desorption from the walls of the measurement chamber, a phenomenon which is observed during the emptying process. The authors give finally actual examples of how to use the results. The apparatus built makes it possible to detect, in less than ten minutes, contamination by tritiated water vapour in the presence of other active gases, in a measurement range of between 3 and 2200 MPC, and with an accuracy of about 25 per cent. A transposition to calculations of the risk to workers should be made with the utmost caution; an envelope of this risk can be drawn up more or less accurately depending on particular cases. (authors)

  17. (Environmental investigation of ground water contamination at Wright-Patterson Air Force Base, Ohio)

    Energy Technology Data Exchange (ETDEWEB)

    1991-10-01

    In April 1990, Wright-Patterson Air Force Base (WPAFB) initiated an effort for the evaluation of potential removal of ground water contamination at the Base. This report presents a current assessment of the nature and extent of the contamination believed to be migrating across the southwestern boundary of Area C and the northern boundary of Area B based upon analysis of existing environmental data obtained from several sources. The existing data base indicates widespread, low-level contamination moving across Base boundaries at levels that pose no immediate threat to the Mad River Valley well fields. An investigation by the City of Dayton in May and June 1990, however, implies that a more identifiable plume of PCE and TCE may be crossing the southwestern boundary of Area C immediately downgradient of Landfill 5. More data is needed to delineate ground water contamination and to design and implement a suitable control system. This report concludes that although an extensive study of the boundaries in question would be the preferred approach, a limited, focused investigation and subsequent feasibility study can be accomplished with a reasonable certainty of achieving the desired outcome of this project.

  18. Hospital ventilation standards and energy conservation: chemical contamination of hospital air. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Rainer, D.; Michaelsen, G.S.

    1980-03-01

    In an era of increasing energy conservation consciousness, a critical reassessment of the validity of hospital ventilation and thermal standards is made. If current standards are found to be excessively conservative, major energy conservation measures could be undertaken by rebalancing and/or modification of current HVAC systems. To establish whether or not reducing ventilation rates would increase airborne chemical contamination to unacceptable levels, a field survey was conducted to develop an inventory and dosage estimates of hospital generated airborne chemical contaminants to which patients, staff, and visitors are exposed. The results of the study are presented. Emphasis is on patient exposure, but an examination of occupational exposure was also made. An in-depth assessment of the laboratory air environment is documented. Housekeeping products used in survey hospitals, hazardous properties of housekeeping chemicals and probable product composition are discussed in the appendices.

  19. An approach to represent a combined exposure to air pollution

    OpenAIRE

    Mieczyslaw Szyszkowicz

    2015-01-01

    Objectives: The objective of this study was to present a technique for estimating the effect of ambient air pollution mix on health outcomes. Material and Methods: We created a technique of indexing air pollution mix as a cause of the increased odds of health problems. As an illustrative example, we analyzed the impact of pollution on the frequency of emergency department (ED) visits due to colitis among young patients (age < 15 years, N = 11 110). Our technique involves 2 steps. First, we co...

  20. Assessing Aircraft Supply Air to Recommend Compounds for Timely Warning of Contamination

    Science.gov (United States)

    Fox, Richard B.

    Taking aircraft out of service for even one day to correct fume-in-cabin events can cost the industry roughly $630 million per year in lost revenue. The quantitative correlation study investigated quantitative relationships between measured concentrations of contaminants in bleed air and probability of odor detectability. Data were collected from 94 aircraft engine and auxiliary power unit (APU) bleed air tests from an archival data set between 1997 and 2011, and no relationships were found. Pearson correlation was followed by regression analysis for individual contaminants. Significant relationships of concentrations of compounds in bleed air to probability of odor detectability were found (p<0.05), as well as between compound concentration and probability of sensory irritancy detectability. Study results may be useful to establish early warning levels. Predictive trend monitoring, a method to identify potential pending failure modes within a mechanical system, may influence scheduled down-time for maintenance as a planned event, rather than repair after a mechanical failure and thereby reduce operational costs associated with odor-in-cabin events. Twenty compounds (independent variables) were found statistically significant as related to probability of odor detectability (dependent variable 1). Seventeen compounds (independent variables) were found statistically significant as related to probability of sensory irritancy detectability (dependent variable 2). Additional research was recommended to further investigate relationships between concentrations of contaminants and probability of odor detectability or probability of sensory irritancy detectability for all turbine oil brands. Further research on implementation of predictive trend monitoring may be warranted to demonstrate how the monitoring process might be applied to in-flight application.

  1. Contents of nitrogen and phosphorus in leaves of woody plants under conditions of air contamination with industrial wastes

    Energy Technology Data Exchange (ETDEWEB)

    Tarabrin, V.P.; Shatskaya, R.M.; Chernyshova, L.V.

    1971-01-01

    A study of nitrogen and phosphorus contents in leaves of woody plants was conducted against a background of different air and soil contamination with wastes of metallurgic and coke-chemical plants. It is found that content of total protein nitrogen and phosphorus in leaves of woody plants decreases with aging of the leaves (from spring to autumn) in all the plants under study. Air contamination causes at the beginning of the vegetation period an increase and then, under conditions of great contamination a drop in the content of total nitrogen in comparison with control. The drought resistant plants - Quercus robur L. and Robinia pseudoacacia L. under conditions of air contamination with industrial wastes preserve exchange of nitrogen protein and phosphorus at a higher level in comparison with less resistant Aesculus hippocastanum L. and Tilia parviflora Ehrh.

  2. Evaluating the Spatial Distribution of Toxic Air Contaminants in Multiple Ecosystem Indicators in the Sierra Nevada-Southern Cascades

    Science.gov (United States)

    Nanus, L.; Simonich, S. L.; Rocchio, J.; Flanagan, C.

    2013-12-01

    Toxic air contaminants originating from agricultural areas of the Central Valley in California threaten vulnerable sensitive receptors including surface water, vegetation, snow, sediments, fish, and amphibians in the Sierra Nevada-Southern Cascades region. The spatial distribution of toxic air contaminants in different ecosystem indicators depends on variation in atmospheric concentrations and deposition, and variation in air toxics accumulation in ecosystems. The spatial distribution of organic air toxics and mercury at over 330 unique sampling locations and sample types over two decades (1990-2009) in the Sierra Nevada-Southern Cascades region were compiled and maps were developed to further understand spatial patterns and linkages between air toxics deposition and ecological effects. Potential ecosystem impacts in the Sierra Nevada-Southern Cascades region include bioaccumulation of air toxics in both aquatic and terrestrial ecosystems, reproductive disruption, and immune suppression. The most sensitive ecological end points in the region that are affected by bioaccumulation of toxic air contaminants are fish. Mercury was detected in all fish and approximately 6% exceeded human consumption thresholds. Organic air toxics were also detected in fish yielding variable spatial patterns. For amphibians, which are sensitive to pesticide exposure and potential immune suppression, increasing trends in current and historic use pesticides are observed from north to south across the region. In other indicators, such as vegetation, pesticide concentrations in lichen increase with increasing elevation. Current and historic use pesticides and mercury were also observed in snowpack at high elevations in the study area. This study shows spatial patterns in toxic air contaminants, evaluates associated risks to sensitive receptors, and identifies data gaps. Future research on atmospheric modeling and information on sources is needed in order to predict which ecosystems are the

  3. Vapor extraction, air sparging, and bioventing in combination form a technically and cost effective scenario to remediate petroleum hydrocarbons

    International Nuclear Information System (INIS)

    When the appropriate site conditions exist, air sparging, vapor extraction and bioventing can be combined to form a technically and cost effective scenario to remediate petroleum hydrocarbon contaminated soils. A former Gulf Terminal in Upstate New York meets these conditions. The site geology consists of highly permeable sands and gravels with only trace amounts of silt. The groundwater table is approximately 15 feet below the ground surface which provides an ideal vadose zone. The site contaminants are petroleum fuel residuals primarily from the former storage and transfer of gasoline distillates. A series of pilot studies were conducted at the site in July, August, and September of 1994 to determine the validity of the proposed technologies. Based on the pilot study results, it was determined that the combined technologies of soil vapor extraction, air sparging, and bioventing could be used to effectively remediate the site. Using the pilot study data as the design basis, Parsons ES designed and installed a full-scale remediation system to address both the vadose and phreatic zone contaminants. The SVE portion of the system was placed into operation in April of 1995, and to date has removed over 12,000 pounds of petroleum hydrocarbons, including over 30 pounds of benzene. The overall costs for remediating the site including pilot studies, detailed design, system installation, and one year of operation are estimated at $5.60 per cubic yard for the estimated 35,000 cubic yards of contaminated soil at the site. The pilot study, full-scale operational results, and projected remediation costs are the focus of this paper

  4. The circulating air barrier: Effective prevention of liquid contaminant movement through soil

    International Nuclear Information System (INIS)

    Objectives of this task included design, modeling, selection of drilling and surface processing equipment, and development of test procedures and cost estimates for conducting a cold test demonstration of the Circulating Air Barrier (CAB) process. The demonstration configuration is scaled to a prototype CAB system designed specifically for the C Tank Farm at the Hanford Site. The CAB system is designed to function as a containment barrier to prevent contamination of the water table located approximately 200 feet below the base of the C-Tank-Farm underground storage tanks. The CAB system is a desiccant-type barrier designed to prevent the migration of liquid contaminants toward the ground water by using an air circulation and processing system to lower the saturation in a targeted subsurface zone below the saturation level required for liquid flow through that zone. The CAB system offers several important advantages, including the fact that it is a non-physical confinement technology, it has an active monitoring and leak detection capability, it is based on proven, commercially available equipment and oil and gas technologies; it has excellent potential for emergency response and rapid deployment; and offers high potential for integration with other remediation technologies. Demonstration- and full-scale CAB systems have been designed for the Hanford Site as part of this task

  5. Measurements of the spatial distribution of tritium in air above a chronically contaminated surface

    International Nuclear Information System (INIS)

    Tritium in air (HTO) concentrations were measured over a 13 month period above a surface that is chronically contaminated by tritium-bearing groundwater from a waste management area. The measurements were made using passive diffusion samplers, which were sited at six locations (about 100 m apart) at 0.15, 0.9, and 1.8 m above ground level. The diffusion samplers were compact, sampled at a known rate, and required no external power source. They are ideal for remote locations and require a minimum of effort to collect and analyze the data. HTO-in-air concentration peaked in the summer at 500-1500 Bq.m-3 and decreased in the winter to 1-120 Bq.m-3. In general, concentration decreased with height above ground level, implying that HTO is being lost from the surface to the atmosphere. The flux of tritium to the atmosphere must, therefore, be taken into account to estimate the tritium mass balance for a contaminated area. (Author) 3 figs., 5 tabs., 10 refs

  6. (Environmental investigation of ground water contamination at Wright-Patterson Air Force Base, Ohio)

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, Bill

    1991-10-01

    In April 1990, Wright-Patterson Air Force Base (WPAFB), initiated an investigation to evaluate a potential Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) removal action to prevent, to the extent practicable, the offsite migration of contaminated ground water from WPAFB. WPAFB retained the services of the Environmental Management Operations (EMO) and its principle subcontractor, International Technology Corporation (IT) to complete Phase 1 of the environmental investigation of ground-water contamination at WPAFB. Phase 1 of the investigation involves the short-term evaluation and potential design for a program to remove ground-water contamination that appears to be migrating across the western boundary of Area C, and across the northern boundary of Area B along Springfield Pike. Primarily, Task 4 of Phase 1 focuses on collection of information at the Area C and Springfield Pike boundaries of WPAFB. This Sampling and Analysis Plan (SAP) has been prepared to assist in completion of the Task 4 field investigation and is comprised of the Quality Assurance Project Plan (QAPP) and the Field Sampling Plan (FSP).

  7. Combining Solvent Extraction and Bioremediation for Removing Weathered Petroleum from Contaminated Soil

    Institute of Scientific and Technical Information of China (English)

    WU Guo-Zhong; F.COULON; YANG Yue-Wei; LI Hong; SUI Hong

    2013-01-01

    This study aimed to evaluate the efficacy,practicality and sustainability of a combined approach based on solvent extraction and biodegradation to remediate the soils contaminated with high levels of weathered petroleum hydrocarbons.The soils used in this study were obtained from the Shengli Oilfield in China,which had a long history of contamination with high concentrations of petroleum hydrocarbons.The contaminated soils were washed using a composite organic solvent consisting of hexane and pentane (4:1,v/v) and then bioremediated in microcosms which were bioaugmentated with Bacillus subtilis FQ06 strains and/or rhamnolipid.The optimal solvent extraction conditions were determined as extraction for 20 min at 25 ℃ with solvent-soil ratio of 6:1 (v/w).On this basis,total petroleum hydrocarbon was decreased from 140000 to 14000 mg kg-1,which was further reduced to < 4000 mg kg-1 by subsequent bioremediation for 132 d.Sustainability assessment of this integrated technology showed its good performance for both short-and long-term effectiveness.Overall the results encouraged its application for remediating contaminated sites especially with high concentration weathered hydrocarbons.

  8. Development of In Vitro Methods for Toxicity Testing of Workplace Air Contaminants

    Directory of Open Access Journals (Sweden)

    Chris Winder

    2009-04-01

    Full Text Available While the OECD test guidelines and mostly animal assays have been used to study the toxic effects of chemicals for many years, very little is known about the potential toxicity of vast majority of inhaled chemicals. Considering large number of chemicals and complex mixtures present in indoor and outdoor air, heavy reliance on animal test methods appear to be not adequate. Continuing scientific developments are needed to improve the process of safety evaluation for the vast number of chemicals and inhaled materials. The aim of this study was to optimise in vitro methods for toxicity testing of airborne contaminants. An integrated approach was designed in which appropriate exposure techniques were developed. A diversified range of in vitro assays using multiple human cell systems were implemented. Direct exposure of cells to airborne contaminants was developed by culturing cells on porous membranes in conjunction with a horizontal diffusion chamber system. Dose-response curves were generated allowing the measurement of toxicity endpoints. Toxicity ranking of test chemicals, based on obtained IC50 (50% inhibitory concentration values, in different human cells and in vitro assays were determined. Airborne IC50 values were calculated for selected volatile organic compounds (xylene; 5350 ± 328 ppm > toluene; 10500 ± 527 ppm and gaseous contaminants (NO2; 11 ± 3.54 ppm > SO2; 48 ± 2.83 ppm > and NH3; 199 ± 1.41 ppm. Results of this research indicate the significant potential of in vitro methods as an advanced technology for toxicity assessment of airborne contaminants.

  9. Air pollution monitoring using emission inventories combined with the moss bag approach.

    Science.gov (United States)

    Iodice, P; Adamo, P; Capozzi, F; Di Palma, A; Senatore, A; Spagnuolo, V; Giordano, S

    2016-01-15

    Inventory of emission sources and biomonitoring with moss transplants are two different methods to evaluate air pollution. In this study, for the first time, both these approaches were simultaneously applied in five municipalities in Campania (southern Italy), deserving attention for health-oriented interventions as part of a National Interest Priority Site. The pollutants covered by the inventory were CO, NOx, particulate matter (PM10), volatile organic compounds (VOCs), and some heavy metals (As, Cd, Cr, Cu, Hg, Ni, Pb, Se, and Zn). The biomonitoring survey was based on the use of the devitalized moss Hypnum cupressiforme transplanted into bags, following a harmonized protocol. The exposure covered 40 agricultural and urban/residential sites, with half of them located in proximity to roads. The pollutants monitored were Al, As, Cd, Cr, Cu, Fe, Hg, Ni, Pb, Se, and Zn, as well as total polycyclic aromatic hydrocarbons (PAHs) only in five sites. Using the emission inventory approach, high emission loads were detected for all the major air pollutants and the following heavy metals: Cr, Cu, Ni, Pb and Zn, over the entire study area. Arsenic, Pb, and Zn were the elements most accumulated by moss. Total PAH postexposure contents were higher than the preexposure values (~20-50% of initial value). Moss uptakes did not differ substantially among municipalities or within exposure sites. In the five municipalities, a similar spatial pattern was evidenced for Pb by emission inventory and moss accumulation. Both approaches indicated the same most polluted municipality, suggesting their combined use as a valuable resource to reveal contaminants that are not routinely monitored. PMID:26479914

  10. High Concentrations of Organic Contaminants in Air from Ship Breaking Activities in Chittagong, Bangladesh.

    Science.gov (United States)

    Nøst, Therese H; Halse, Anne K; Randall, Scott; Borgen, Anders R; Schlabach, Martin; Paul, Alak; Rahman, Atiqur; Breivik, Knut

    2015-10-01

    The beaches on the coast of Chittagong in Bangladesh are one of the most intense ship breaking areas in the world. The aim of the study was to measure the concentrations of organic contaminants in the air in the city of Chittagong, including the surrounding ship breaking areas using passive air samplers (N = 25). The compounds detected in the highest amounts were the polycyclic aromatic hydrocarbons (PAHs) and short-chain chlorinated paraffins (SCCPs), whereas dichlorodiphenyltrichloroethanes (DDTs), hexachlorobenzene (HCB), and polychlorinated biphenyls (PCBs) were several orders of magnitude lower in comparison. PCBs, PAHs, and HCB were highest at sites near the ship breaking activities, whereas DDTs and SCCPs were higher in the urban areas. Ship breaking activities likely act as atmospheric emission sources of PCBs, PAHs, and HCB, thus adding to the international emphasis on responsible recycling of ships. Concentrations of PAHs, PCBs, DDTs, HCB, and SCCPs in ambient air in Chittagong are high in comparison to those found in similar studies performed in other parts of Asia. Estimated toxic equivalent quotients indicate elevated human health risks caused by inhalation of PAHs at most sites. PMID:26351879

  11. Testing Single and Combinations of Amendments for Stabilization of Metals in Contrasting Extremely Contaminated Soils

    Directory of Open Access Journals (Sweden)

    Siebielec G.

    2013-04-01

    Full Text Available Metals can be stabilized by soil amendments that increase metals adsorption or alter their chemical forms. Such treatments may limit the risk related to the contamination through reduction of metal transfer to the food chain (reduction of metal uptake by plants and its availability to soil organisms and metals migration within the environment. There is a need for experiments comparing various soil amendments available at reasonable amounts under similar environmental conditions. The other question is whether all components of soil environment or soil functions are similarly protected after remediation treatment. We conducted a series of pot studies to test some traditional and novel amendments and their combinations. The treatments were tested for several highly Zn/Cd/Pb contaminated soils. Among traditional amendments composts were the most effective – they ensured plant growth, increased soil microbial activity, reduced Cd in earthworms, reduced Pb bioaccessibility and increased share of unavailable forms of Cd and Pb.

  12. Use of dust fall filters as passive samplers for metal concentrations in air for communities near contaminated mine tailings

    Science.gov (United States)

    Beamer, P.I.; Sugeng, A. J.; Kelly, M.D.; Lothrop, N.; Klimecki, W.; Wilkinson, S.T.; Loh, M.

    2014-01-01

    Mine tailings are a source of metal exposures in many rural communities. Multiple air samples are necessary to assess the extent of exposures and factors contributing to these exposures. However, air sampling equipment is costly and requires trained personnel to obtain measurements, limiting the number of samples that can be collected. Simple, low-cost methods are needed to allow for increased sample collection. The objective of our study was to assess if dust fall filters can serve as passive air samplers and be used to characterize potential exposures in a community near contaminated mine tailings. We placed filters in cylinders, concurrently with active indoor air samplers, in 10 occupied homes. We calculated an estimated flow rate by dividing the mass on each dust fall filter by the bulk air concentration and the sampling duration. The mean estimated flow rate for dust fall filters was significantly different during sampling periods with precipitation. The estimated flow rate was used to estimate metal concentration in the air of these homes, as well as in 31 additional homes in another rural community impacted by contaminated mine tailings. The estimated air concentrations had a significant linear association with the measured air concentrations for beryllium, manganese and arsenic (p<0.05), whose primary source in indoor air is resuspended soil from outdoors. In the second rural community, our estimated metal concentrations in air were comparable to active air sampling measurements taken previously. This passive air sampler is a simple low-cost method to assess potential exposures near contaminated mining sites. PMID:24469149

  13. Simultaneous removal of formaldehyde and benzene in indoor air with a combination of sorption- and decomposition-type air filters.

    Science.gov (United States)

    Sekine, Yoshika; Fukuda, Mitsuru; Takao, Yosuke; Ozano, Takahiro; Sakuramoto, Hikaru; Wang, Kuan Wei

    2011-12-01

    Urgent measures for indoor air pollution caused by volatile organic compounds are required in urban areas of China. Considering indoor air concentration levels and hazardous properties, formaldehyde and benzene should be given priority for pollution control in China. The authors proposed the use of air-cleaning devices, including stand-alone room air cleaners and in-duct devices. This study aimed to find the best combination of sorption and decomposition filters for the simultaneous removal of formaldehyde and benzene, employing four types of air filter units: an activated charcoal filter (ACF), an ACF impregnated with a trapping agent for acidic gases (ACID), a MnO2 filter (MDF) for oxidative decomposition of formaldehyde at room temperature and a photocatalyst filter (PHOTO) coupled with a parallel beam ultraviolet (UV) irradiation device. The performance of the combined systems under air flow rates of 35-165 m3 h(-1) was evaluated in a test chamber (2 m3) with a constant gas generation system. The experimental results and data analysis using a kinetic approach showed the combined system of ACF, PHOTO and MDF significantly reduced both concentrations of formaldehyde and benzene in air without any unpleasant odours caused by the UV-induced photocatalytic reaction. The system was then evaluated in a full-size laboratory (22 m3). This test proved the practical performance of the system even at full scale, and also suggested that the filters should be arranged in the order of PHOTO/ACF/MDF from upstream to downstream. The proposed system has the potential of being used for improving indoor air quality of houses and buildings in China. PMID:22439587

  14. An Evaluation of Antifungal Agents for the Treatment of Fungal Contamination in Indoor Air Environments

    Directory of Open Access Journals (Sweden)

    Senthaamarai Rogawansamy

    2015-06-01

    Full Text Available Fungal contamination in indoor environments has been associated with adverse health effects for the inhabitants. Remediation of fungal contamination requires removal of the fungi present and modifying the indoor environment to become less favourable to growth.  This may include treatment of indoor environments with an antifungal agent to prevent future growth. However there are limited published data or advice on chemical agents suitable for indoor fungal remediation. The aim of this study was to assess the relative efficacies of five commercially available cleaning agents with published or anecdotal use for indoor fungal remediation. The five agents included two common multi-purpose industrial disinfectants (Cavicide® and Virkon®, 70% ethanol, vinegar (4.0%-4.2% acetic acid, and a plant-derived compound (tea tree (Melaleuca alternifolia oil tested in both a liquid and vapour form. Tea tree oil has recently generated interest for its antimicrobial efficacy in clinical settings, but has not been widely employed for fungal remediation. Each antifungal agent was assessed for fungal growth inhibition using a disc diffusion method against a representative species from two common fungal genera, (Aspergillus fumigatus and Penicillium chrysogenum, which were isolated from air samples and are commonly found in indoor air. Tea tree oil demonstrated the greatest inhibitory effect on the growth of both fungi, applied in either a liquid or vapour form. Cavicide® and Virkon® demonstrated similar, although less, growth inhibition of both genera. Vinegar (4.0%–4.2% acetic acid was found to only inhibit the growth of P. chrysogenum, while 70% ethanol was found to have no inhibitory effect on the growth of either fungi. There was a notable inhibition in sporulation, distinct from growth inhibition after exposure to tea tree oil, Virkon®, Cavicide® and vinegar. Results demonstrate that common cleaning and antifungal agents differ in their capacity to

  15. Combined effects of road traffic noise and ambient air pollution in relation to risk for stroke?

    DEFF Research Database (Denmark)

    Sørensen, Mette; Lühdorf, Pernille; Ketzel, Matthias;

    2014-01-01

    Exposure to road traffic noise and air pollution have both been associated with risk for stroke. The few studies including both exposures show inconsistent results. We aimed to investigate potential mutual confounding and combined effects between road traffic noise and air pollution in association...... to 2009 were identified in national registers and road traffic noise and air pollution were modeled for all addresses. Analyses were done using Cox regression. A higher mean annual exposure at time of diagnosis of 10µg/m(3) nitrogen dioxide (NO2) and 10dB road traffic noise at the residential address...... was found for combination of high noise and high NO2 (IRR=1.28; 95% CI=1.09-1.52). Fatal stroke was positively associated with air pollution and not with traffic noise. In conclusion, in mutually adjusted models road traffic noise and not air pollution was associated ischemic stroke, while only air...

  16. Combined fuel and air staged power generation system

    Science.gov (United States)

    Rabovitser, Iosif K; Pratapas, John M; Boulanov, Dmitri

    2014-05-27

    A method and apparatus for generation of electric power employing fuel and air staging in which a first stage gas turbine and a second stage partial oxidation gas turbine power operated in parallel. A first portion of fuel and oxidant are provided to the first stage gas turbine which generates a first portion of electric power and a hot oxidant. A second portion of fuel and oxidant are provided to the second stage partial oxidation gas turbine which generates a second portion of electric power and a hot syngas. The hot oxidant and the hot syngas are provided to a bottoming cycle employing a fuel-fired boiler by which a third portion of electric power is generated.

  17. COMBINED EFFECT OF WATER CONTAMINATION WITH COBALT AND NICKEL ON METABOLISM OF ALBINO (WISTAR) RATS

    OpenAIRE

    Z. Kechrid, F. Dahdouh, R. M. Djabar, N. Bouzerna

    2006-01-01

    The contamination of water by metal compounds is a worldwide environmental problem. Concentration of metals is widely related to biochemical values, which are used in diseases diagnosis due to environmental toxicity. The sub-chronic combined effects of nickel and cobalt on body weight gain and biochemical parameters were determined and compared with those of Ni (2+) or Co (2+) alone in 6 weeks male albino (Wistar) rats. Animals were given drinking solutions of NiSO4 6H2O [Ni (II) cation, LD50...

  18. Combination of emulsion chamber and air shower array at Mt. Chacaltaya

    International Nuclear Information System (INIS)

    Data of 34 familes with the accompanying air showers, observed by the combination of emulsion chamber and air shower array at Mt. Chacaltaya, are presented. Comparison with the simulation calculation concludes that a change is necessary in the characteristics of hadron interactions in E0≥1015 eV

  19. An experimental study of thermal comfort at different combinations of air and mean radiant temperature

    DEFF Research Database (Denmark)

    Simone, Angela; Olesen, Bjarne W.

    2009-01-01

    It is often discussed if a person prefers a low air temperature (ta) and a high mean radiant temperature (tr), vice-versa or it does not matter as long as the operative temperature is acceptable. One of the hypotheses is that it does not matter for thermal comfort but for perceived air quality, a...... lower air temperature is preferred. This paper presents an experimental study with 30 human subjects exposed to three different combinations of air- and mean radiant temperature with an operative temperature around 23 °C. The subjects gave subjective evaluations of thermal comfort and perceived air...... quality during the experiments. The PMV-index gave a good estimation of thermal sensation vote (TSV) when the air and mean radiant temperature were the same. In the environment with different air- and mean radiant temperatures, a thermal comfort evaluation shows an error up to 1 scale unit on the 7-point...

  20. (Environmental investigation of ground water contamination at Wright-Patterson Air Force Base, Ohio)

    Energy Technology Data Exchange (ETDEWEB)

    1992-03-01

    An environmental investigation of ground water conditions has been undertaken at Wright-Patterson Air Force Base (WPAFB), Ohio to obtain data to assist in the evaluation of a potential removal action to prevent, to the extent practicable, migration of the contaminated ground water across Base boundaries. Field investigations were limited to the central section of the southwestern boundary of Area C and the Springfield Pike boundary of Area B. Further, the study was limited to a maximum depth of 150 feet below grade. Three primary activities of the field investigation were: (1) installation of 22 monitoring wells, (2) collection and analysis of ground water from 71 locations, (3) measurement of ground water elevations at 69 locations. Volatile organic compounds including trichloroethylene, perchloroethylene, and/or vinyl chloride were detected in concentrations exceeding Maximum Contaminant Levels (MCL) at three locations within the Area C investigation area. Ground water at the Springfield Pike boundary of Area B occurs in two primary units, separated by a thicker-than-expected clay layers. One well within Area B was determined to exceed the MCL for trichloroethylene.

  1. (Environmental investigation of ground water contamination at Wright-Patterson Air Force Base, Ohio)

    Energy Technology Data Exchange (ETDEWEB)

    1991-10-01

    In April 1990 Wright-Patterson Air Force Base (WPAFB) initiated an investigation to evaluate a potential CERCLA removal action to prevent, to the extent practicable, the migration of ground-water contamination in the Mad River Valley Aquifer within and across WPAFB boundaries. The action will be based on a Focused Feasibility Study with an Action Memorandum serving as a decision document that is subject to approval by the Ohio Environmental Protection Agency. The first phase (Phase 1) of this effort involves an investigation of ground-water contamination migrating across the southwest boundary of Area C and across Springfield Pike adjacent to Area B. Task 4 of Phase 1 is a field investigation to collect sufficient additional information to evaluate removal alternatives. The field investigation will provide information in the following specific areas of study: water-level data which will be used to permit calibration of the ground-water flow model to a unique time in history; and ground-water quality data which will be used to characterize the current chemical conditions of ground water.

  2. Combination of air-source heat pumps with liquid desiccant dehumidification of air

    International Nuclear Information System (INIS)

    Highlights: ► We propose a frost-free air-source heat pump system with integrated desiccant. ► The system can provide heating load continuously and humidify room. ► The coefficient of performance of the system is 2.6 at Ta = −7 °C and RH = 80%. ► The heating load of solution is 3–4 times larger than cooling load of solution. - Abstract: This paper proposes a frost-free air source heat pump system with integrated liquid desiccant dehumidification, in which frosting can be retarded by dehumidifying air before entering an outdoor heat exchanger. And the water removed from the air is used to humidify a room. Simulation is carried out at a dry-bulb temperature of −7 to 5.5 °C and a relative humidity of 80% depending on the frosting conditions. The results show that the coefficient of performance (COP) is in the range of 2.6–2.9, which is 30–40% higher than that of heat pump heating integrated with an electric heater humidifying system. And it is found that the optimum value of the concentration of lithium chloride aqueous solution is 37% for the frost-free operation mode. Experiments are conducted for liquid desiccant system under low air temperature and high relative humidity conditions. Experimental results show that the dew point of the dehumidified air is decreased by 8 °C and the humidity ratio of the humidified air is kept at 8.1 g kg−1, which ensures the frost-free operation of the heat pump evaporator and the comfortable level of room humidity simultaneously. The heating load of solution is 3–4.5 times larger than cooling load of solution, which agrees with the assumption given at the part of the simulation. Furthermore, the deviations between the calculated COPLHRU and the experimental results are within 33%.

  3. Combined cadmium and elevated ozone affect concentrations of cadmium and antioxidant systems in wheat under fully open-air conditions

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Hongyan, E-mail: hyguo@nju.edu.cn [State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Science, Nanjing 210008 (China); State Key Laboratory of Pollution Control and Resource Reuse, School of Environment, Nanjing University, Nanjing 210093 (China); Institute for Climate and Global Change Research (ICGCR), Nanjing University, Nanjing 210093 (China); Tian, Ran [State Key Laboratory of Pollution Control and Resource Reuse, School of Environment, Nanjing University, Nanjing 210093 (China); Zhu, Jianguo, E-mail: jgzhu@issas.ac.cn [State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Science, Nanjing 210008 (China); Zhou, Hui; Pei, Daping; Wang, Xiaorong [State Key Laboratory of Pollution Control and Resource Reuse, School of Environment, Nanjing University, Nanjing 210093 (China)

    2012-03-30

    Highlights: Black-Right-Pointing-Pointer Combined effect of elevated O{sub 3} and Cd levels on wheat was studied using the free-air concentration enrichment system. Black-Right-Pointing-Pointer Elevated O{sub 3} levels result in an increased concentration of Cd in wheat plants grown on Cd-contaminated soils. Black-Right-Pointing-Pointer Combined cadmium and elevated O{sub 3} have a significantly synergic effect on oxidative stress in wheat shoots. - Abstract: Pollution of the environment with both ozone (O{sub 3}) and heavy metals has been steadily increasing. An understanding of their combined effects on plants, especially crops, is limited. Here we studied the effects of elevated O{sub 3} on oxidative stress and bioaccumulation of cadmium (Cd) in wheat under Cd stress using a free-air concentration enrichment (FACE) system. In this field experiment in Jiangdu (Jiangsu Province, China), wheat plants were grown in pots containing soil with various concentrations of cadmium (0, 2, and 10 mg kg{sup -1} Cd was added to the soil) under ambient conditions and under elevated O{sub 3} levels (50% higher than the ambient O{sub 3}). Present results showed that elevated O{sub 3} led to higher concentrations of Cd in wheat tissues (shoots, husk and grains) with respect to contaminated soil. Combined exposure to Cd and elevated O{sub 3} levels strongly affected the antioxidant isoenzymes POD, APX and CAT and accelerated oxidative stress in wheat leaves. Our results suggest that elevated O{sub 3} levels cause a reduction in food quality and safety.

  4. Combined effects of air temperature, wind, and radiation on the resting metabolism of avian raptors

    International Nuclear Information System (INIS)

    American kestrels, Falco sparverius; red-tailed hawks, Buteo jamaicensis; and golden eagles, Aquila chrysaetos, were perched in a wind tunnel and subjected to various combinations of air temperature, wind, and radiation. Oxygen consumption was measured under the various combinations of environmental variables, and multiple regression equations were developed to predict resting metabolism as a function of body mass, air temperature, wind speed, and radiation load

  5. Combined education and skin antisepsis intervention for persistently high blood-culture contamination rates in neonatal intensive care.

    Science.gov (United States)

    O'Connor, C; Philip, R K; Powell, J; Slevin, B; Quinn, C; Power, L; O'Connell, N H; Dunne, C P

    2016-05-01

    Contaminated blood cultures represent challenges regarding diagnosis, duration of hospitalization, antimicrobial use, pharmacy and laboratory costs. Facing problematic neonatal blood culture contamination (3.8%), we instigated a successful intervention combining skin antisepsis using sterile applicators with 2% chlorhexidine gluconate in 70% isopropanol prior to phlebotomy (replacing 70% isopropanol) and staff education. In the six months prior to intervention, 364 neonatal peripheral blood samples were collected. Fourteen (3.8%) were contaminated. In the post-intervention six months, 314 samples were collected. Three (0.96%) were contaminated, representing significant improvement (Fisher's exact test: P = 0.0259). No dermatological sequelae were observed. The improvement has been sustained. PMID:26944902

  6. Immunomagnetic Separation Combined with Real-Time Reverse Transcriptase PCR Assays for Detection of Norovirus in Contaminated Food▿

    OpenAIRE

    Park, Youngbin; Cho, You-Hee; Jee, Youngmee; Ko, GwangPyo

    2008-01-01

    We developed an immunomagnetic separation (IMS) technique combined with real-time TaqMan reverse transcriptase PCR (RT-PCR), which allowed detection of norovirus at a level as low as 3 to 7 RT-PCR units from artificially contaminated strawberries. The inoculum recovery rate ranged from 14 to 30%. The data demonstrate that IMS combined with real-time RT-PCR will be useful as a rapid and sensitive method for detecting food-borne microbial contaminants.

  7. Applicability of the Environmental Relative Moldiness Index for Quantification of Residential Mold Contamination in an Air Pollution Health Effects Study

    OpenAIRE

    Ali Kamal; Janet Burke; Stephen Vesper; Stuart Batterman; Alan Vette; Christopher Godwin; Marina Chavez-Camarena; Gary Norris

    2014-01-01

    The Near-Road Exposures and Effects of Urban Air Pollutants Study (NEXUS) investigated the impact of exposure to traffic-related air pollution on the respiratory health of asthmatic children in Detroit, Michigan. Since indoor mold exposure may also contribute to asthma, floor dust samples were collected in participants homes (n = 112) to assess mold contamination using the Environmental Relative Moldiness Index (ERMI). The repeatability of the ERMI over time, as well as ERMI differences betwe...

  8. Air sparging as a supporting measure to redevelopment of a LCFC-contaminated industrial site; Air-Sparging als begleitende Sanierungsmassnahme an einem LCKW-kontaminierten Industriestandort

    Energy Technology Data Exchange (ETDEWEB)

    Breh, W.; Suttheimer, J. [Karlsruhe Univ. (T.H.) (Germany). Lehrstuhl fuer Angewandte Geologie; Holub, B. [G.U.T Linz (Austria)

    1998-12-31

    On a company ground in Vorchdorf, Austria, from the 23{sup rd} to 26{sup th} of July 1996 an air-sparging experiment has been carried out as a supporting measure to a running redevelopment of an LCKW-contamination case. On this occasion compressed air, from which the oil had been extracted, was blown into the contaminated aquifer through a well with a maximum excess pressure of 0,6 MPa. The blowing-in of compressed air caused a mobilisation of the harmful substances in the ground water and the soil air. As a result circa 2,7 kg LCKW could be removed from the underground through neighbouring ground water and soil air wells. For the observed period of time this meant a tripling of the rate of discharge. On the basis of the obtained data we suggested a routine interval of blowing in compressed air into the well 1516. A blowing-in of compressed air into the highly contaminated wells 1617 and 1625 can not be realised until the construction of upstream situated injection wells, because of the danger of an uncontrollable spread of the harmful substances. (orig.) [Deutsch] Auf einem Firmengelaende in Vorchdorf, Oesterreich, wurde vom 23.07. bis 26.07.1996 ein Air-Sparging-Versuch als unterstuetzende Massnahme zur laufenden hydraulisch-pneumatischen Sanierung eines LCKW-Schadensfalles durchgefuehrt. Hierbei wurde entoelte Druckluft ueber einen Brunnen mit einem maximalen Ueberdruck von 600 mbar in den kontaminierten Aquifer eingeblasen. Die Drucklufteinblasung fuehrte zu einer Mobilisierung von Schadstoffen im Grundwasser und in der Bodenluft, so dass ueber benachbarte Grundwasser- und Bodenluftfoerderbrunnen ca. 2,7 kg LCKW aus dem Untergrund entfernt werden konnten. Fuer den Beobachtungszeitraum bedeutet dies eine Verdreifachung des Schadstoffaustrags. Aufgrund der gewonnenen Daten wird ein routinemaessiger Intervallbetrieb der Drucklufteinblasung in einen der Brunnen vorgeschlagen. Fuer zwei kontaminierte Brunnen ist eine Drucklufteinblasung wegen der Gefahr einer

  9. Characterisation of radioactive contaminated materials by combined radiometric and spectrometric methods

    International Nuclear Information System (INIS)

    In the present paper, a combined analytical methodology is described, for characterization of radioactive contaminated materials. The subject of testing activities was a set of solutions provided by the Cernavoda NPP, which are originating from processes of radiological survey of workplaces in the plant. In the introduction section, a theoretical approach was given to the origin and nature of main radionuclides occurring in the primary cooling system of the nuclear power plant, with the aim to establish selection criteria and performance requirements for the analytical methods to be used in the development of the characterization methodology. A combination of radiometric and spectrometric methods was selected, based on gross beta counting, high resolution gamma-ray spectrometry and liquid scintillation counting. (authors)

  10. Clam Ruditapes philippinarum recovery from short-term exposure to the combined effect of salinity shifts and Arsenic contamination.

    Science.gov (United States)

    Velez, Catia; Teixeira, Miguel; Wrona, Frederick J; Soares, Amadeu M V M; Figueira, Etelvina; Freitas, Rosa

    2016-04-01

    The current study assessed the biochemical alterations induced in the clam species Ruditapes philippinarum after exposure to salinity shifts (14, 28 and 42) and arsenic (As) contamination (0 and 2mg/L). The capacity of this species to recover (96h and 28 days) after exposure (96h) to both stressors, acting alone and in combination, was also evaluated. After exposure, regardless of the salinity tested, clams contaminated with As showed higher concentrations than non-contaminated specimens. After recovery, As concentration in clams decreased, with contaminated and non-contaminated specimens presenting similar values. The results obtained further demonstrated that exposure to As (2mg/L) at different salinities (salinities 14, 28 and 42) and salinity 42 (As 0mg/L) lead to an increase of lipid peroxidation and detoxification mechanisms in clams, compared with non-contaminated clams at salinities of 14 and 28. After recovery, at salinities 14 and 28, clams previously exposed to As were capable to decrease their oxidative stress to levels found in non-contaminated clams. Nevertheless, at salinity 42 both contaminated and non-contaminated clams did not survive. Overall results of measured energy-related parameters, indicators of oxidative stress, antioxidant and biotransformation enzymes indicated that As exposure and salinity shifts caused biochemical alterations in R. philippinarum, with stronger impacts when both stressors were acting in combination. PMID:26889773

  11. Radiological risk assessment for an urban area: Focusing on an air contamination event

    International Nuclear Information System (INIS)

    This paper specifically discusses an atmospheric dispersion modeling and health risk assessment for Cs-137 to assess the potential and actual effects on human health from an inhalation event due to a radiological terrorist attack in the Seoul metropolitan area, Korea. The source term was assumed to be 5 TBq of Cs-137, introduced into the central part of Seoul's metropolitan area by a terrorist attack. Atmospheric dispersion models can be used to support the decision making and risk assessments when terrorist attacks have happened in an urban area. The concepts of Gaussian plume modeling and computational fluid dynamics modeling were used to calculate the Cs-137 concentration in the air. Mortality risk and morbid risk coefficients for the inhalation of contaminated air were used to assess the human health risk. The mortality and morbidity are 1.12E-2 and 1.64E-2, respectively in case of the Gaussian plume, while 6.23E-3 and 9.13E-3 in case of the computational fluid dynamics model. The results of the modeling are dependent on the terror scenarios and dispersion models. Accordingly, the optimization process is needed for final decision making.

  12. Application of the biological forced air soil treatment (BIOFAST trademark) technology to diesel contaminated soil

    International Nuclear Information System (INIS)

    A subsurface Biological Forced Air Soil Treatment (BIOFAST trademark) system was constructed at the Yellow Freight System, Inc. (Yellow Freight) New Haven facility in Connecticut as a means of expediting the remediation of soils impacted by a diesel fuel release. Prior to beginning construction activities the soils were evaluated for the feasibility of bioremediation based on soil characteristics including contaminant degrading bacteria, moisture content, and pH. Based on results of stimulant tests with oxygen and nutrients, the addition of fertilizer during the construction of the cell was recommended. Following the removal of underground storage tanks, the bioremediation cell was constructed by lining the enlarged excavation with high density polyethylene (HDPE) and backfilling alternating layers of nutrient-laden soil and pea gravel. Passive and active soil vapor extraction (SVE) piping was included in the gravel layers and connected to a blower and vapor treatment unit, operated intermittently to supply oxygen to the subsurface cell. Operating data have indicated that the bacteria are generating elevated levels of CO2, and the SVE unit is evacuating the accumulated CO2 from the soils and replacing it with fresh air. These data suggest that the bioremediation process is active in the soils. Soil samples collected from within the soil pit subsequent to installation and again after 10 months of operation indicate that TPH concentrations have decreased by as much as 50%

  13. Effect of Air Pollution, Contamination and High Altitude on Bronchial Asthma

    Directory of Open Access Journals (Sweden)

    Nesriene El margoushy*, Mohamad El Nashar**, Hatem Khairy*, Nihad El Nashar*, Hala Mohamad

    2013-01-01

    Full Text Available Epidemiological studies have shown that the prevalence of asthma has risen dramatically worldwide and evidence suggests that environmental factors have an important role in the etiology of the disease. Most respiratory diseases are caused by airborne agents. Our lungs are uniquely vulnerable to contamination from the air we breathe. Air pollution exposure is associated with increased asthma and allergy morbidity and is a suspected contributor to the increasing prevalence of allergic conditions. Observational studies continue to strengthen the association between air pollution and allergic respiratory disease. The effects of air pollution should be viewed in two different groups: healthy people and people with chronic heart or lung disease. Although the fundamental causes of asthma are not completely understood, the strongest risk factors for developing asthma are inhaled asthma triggers. These include: indoor allergens (for example house dust mites in bedding, carpets and stuffed furniture, pollution and pet dander, outdoor allergens (such as pollens and moulds, tobacco smoke and chemical irritants in the workplace. Other triggers can include cold air, extreme emotional arousal such as anger or fear, and physical exercise. Even certain medications can trigger asthma such as aspirin and other non-steroid anti-inflammatory drugs, and beta-blockers. Urbanization has also been associated with an increase in asthma; however the exact nature of this relationship is unclear. Medication is not the only way to control asthma. It is also important to avoid asthma triggers - stimuli that irritate and inflame the airways. Prevalence of asthma is generally low within the Middle East, although high rates have been recorded in the Kingdom of Saudi Arabia, Kuwait, Lebanon, and Israel. The prevalence of asthma and asthma-related symptoms is high among 16- to 18-year-old adolescents in Saudi Arabia, and the symptoms are more common in boys than in girls

  14. Electroremediation of PCB contaminated soil combined with iron nanoparticles: Effect of the soil type.

    Science.gov (United States)

    Gomes, Helena I; Dias-Ferreira, Celia; Ottosen, Lisbeth M; Ribeiro, Alexandra B

    2015-07-01

    Polychlorinated biphenyls (PCB) are carcinogenic and persistent organic pollutants that accumulate in soils and sediments. Currently, there is no cost-effective and sustainable remediation technology for these contaminants. In this work, a new combination of electrodialytic remediation and zero valent iron particles in a two-compartment cell is tested and compared to a more conventional combination of electrokinetic remediation and nZVI in a three-compartment cell. In the new two-compartment cell, the soil is suspended and stirred simultaneously with the addition of zero valent iron nanoparticles. Remediation experiments are made with two different historically PCB contaminated soils, which differ in both soil composition and contamination source. Soil 1 is a mix of soils with spills of transformer oils, while Soil 2 is a superficial soil from a decommissioned school where PCB were used as windows sealants. Saponin, a natural surfactant, was also tested to increase the PCB desorption from soils and enhance dechlorination. Remediation of Soil 1 (with highest pH, carbonate content, organic matter and PCB concentrations) obtained the maximum 83% and 60% PCB removal with the two-compartment and the three-compartment cell, respectively. The highest removal with Soil 2 were 58% and 45%, in the two-compartment and the three-compartment cell, respectively, in the experiments without direct current. The pH of the soil suspension in the two-compartment treatment appears to be a determining factor for the PCB dechlorination, and this cell allowed a uniform distribution of the nanoparticles in the soil, while there was iron accumulation in the injection reservoir in the three-compartment cell. PMID:25841071

  15. Thermal environment and air quality in office with personalized ventilation combined with chilled ceiling

    DEFF Research Database (Denmark)

    Lipczynska, Aleksandra; Kaczmarczyk, Jan; Melikov, Arsen Krikor

    2015-01-01

    The thermal environment and air quality conditions provided with combined system of chilled ceiling and personalized ventilation (PV) were studied in a simulated office room for two occupants. The proposed system was compared with total volume HVAC solutions used today, namely mixing ventilation...... and chilled ceiling combined with mixing ventilation. The objective of the study was to evaluate whether PV can be the only ventilation system in the rooms equipped with chilled ceiling. The room air temperature was 26°C in cases with traditional systems and 28°C when PV was used. PV supplied air with...

  16. Cat serum contamination by phthalates, PCBs, and PBDEs versus food and indoor air.

    Science.gov (United States)

    Braouezec, Clélie; Enriquez, Brigitte; Blanchard, Martine; Chevreuil, Marc; Teil, Marie-Jeanne

    2016-05-01

    A wide variety of endocrine disrupting compounds (EDCs) with semi-volatile properties are emitted to indoor air and, thus, humans might get exposed to these compounds. Pet cats spend the major part of their lifetime at home and might integrate indoor contamination so that they could mirror the human exposure. Three classes of EDCs, polybromodiphenyl ethers (PBDEs), polychlorinated biphenyls (PCBs), and phthalates (PAEs), were simultaneously considered and quantified in the serum of cats (Felis silvestris catus) living in the Paris area (France). The main compound concentrations by decreasing importance order were as follows: for PAEs, di-n-butyl phthalate (79,900 ng L(-1)) next di-iso-butyl phthalate (53,200 ng L(-1)), di-iso-nonyl phthalate (43,800 ng L(-1)), and di-ethylhexyl phthalate (32,830 ng L(-1)); for PCBs, CB153 (1378 ng L(-1)) next CB52 (509 ng L(-1)), CB101 (355 ng L(-1)), CB110 (264 ng L(-1)), and CB118 (165 ng L(-1)); and for PBDEs, BDE 153/154 (35 ng L(-1)) next BDE47 (10.7 ng L(-1)). Total serum concentrations as mean ± standard deviation were 107 ± 98 μg L(-1) for ∑9PAEs, 2799 ± 944 ng L(-1) for ∑19PCBs, and 56 ± 21 ng L(-1) for ∑9BDEs. The three chemical groups were found in cat food: 0.088 ng g(-1) for ∑9BDEs, 1.7 ng g(-1) for ∑19PCBs, and 2292 ng g(-1) for ∑9PAEs and in indoor air: 0.063 ng m(-3) for ∑9BDEs, 1.5 ng m(-3) for ∑19PCBs, and 848 ng m(-3) for ∑9PAEs. Contaminant intake by food ingestion was approximately 100-fold higher than that by indoor air inhalation. PMID:26841781

  17. Global Carbon Monoxide Products from Combined AIRS, TES and MLS Measurements on A-Train Satellites

    Science.gov (United States)

    Warner, Juying X.; Yang, R.; Wei, Z.; Carminati, F.; Tangborn, A.; Sun, Z.; Lahoz, W.; Attie, J. L.; El Amraoui, L.; Duncan, B.

    2014-01-01

    This study tests a novel methodology to add value to satellite data sets. This methodology, data fusion, is similar to data assimilation, except that the background modelbased field is replaced by a satellite data set, in this case AIRS (Atmospheric Infrared Sounder) carbon monoxide (CO) measurements. The observational information comes from CO measurements with lower spatial coverage than AIRS, namely, from TES (Tropospheric Emission Spectrometer) and MLS (Microwave Limb Sounder). We show that combining these data sets with data fusion uses the higher spectral resolution of TES to extend AIRS CO observational sensitivity to the lower troposphere, a region especially important for air quality studies. We also show that combined CO measurements from AIRS and MLS provide enhanced information in the UTLS (upper troposphere/lower stratosphere) region compared to each product individually. The combined AIRS-TES and AIRS-MLS CO products are validated against DACOM (differential absorption mid-IR diode laser spectrometer) in situ CO measurements from the INTEX-B (Intercontinental Chemical Transport Experiment: MILAGRO and Pacific phases) field campaign and in situ data from HIPPO (HIAPER Pole-to-Pole Observations) flights. The data fusion results show improved sensitivities in the lower and upper troposphere (20-30% and above 20%, respectively) as compared with AIRS-only version 5 CO retrievals, and improved daily coverage compared with TES and MLS CO data.

  18. Data mining of plasma peptide chromatograms for biomarkers of air contaminant exposures

    Directory of Open Access Journals (Sweden)

    Vincent Renaud

    2008-01-01

    Full Text Available Abstract Background Interrogation of chromatographic data for biomarker discovery becomes a tedious task due to stochastic variability in retention times arising from solvent and column performance. The difficulty is further compounded when the effects of exposure (e.g. to environmental contaminants and biological variability result in varying numbers and intensities of peaks among chromatograms. Results We developed a software tool to correct the stochastic time shifts in chromatographic data through iterative selection of landmark peaks and isometric interpolation to improve alignment of all chromatographic peaks. To illustrate application of the tool, plasma peptides from Fischer rats exposed for 4 h to clean air or Ottawa urban particles (EHC-93 were separated by HPLC with autofluorescence detection, and the retention time shifts between chromatograms were corrected (dewarped. Both dewarped and non-dewarped datasets were then mined for models containing peptide peaks that best discriminate among the treatment groups using ClinproTools™. In general, models generated by dewarped datasets were able to better classify test sample chromatograms into either clean air or EHC-93 exposure groups, and 0 or 24 h post-recovery time groups. Peak areas of peptides in a model that produced the best discrimination of treatment groups were analyzed by two-way ANOVA with exposure (clean air, EHC-93 and recovery time (0 h, 24 h as factors. Statistically significant (p Conclusion Our software tool provides a simple and portable approach for alignment of chromatograms with complex, bi-directional retention time shifts prior to data mining. Reliable biomarker discovery can be achieved through chromatographic dewarping using our software followed by pattern recognition by commercial data mining applications.

  19. Combined desalination and solar-assisted air-conditioning system

    International Nuclear Information System (INIS)

    Analysis of a new desalination process utilizing low grade thermal energy is presented. In this process, fresh water is distilled from saline water under near-vacuum pressures created by passive means, enabling low-temperature distillation with lower energy requirements. The energy for low-temperature distillation is provided by a thermal energy storage (TES) system maintained at 55 deg. C utilizing any low grade waste heat source. In this study, heat rejected by the condenser of a modified absorption refrigeration system (ARS) is evaluated as a possible source to drive this desalination process. The energy for the generator of the ARS is provided by a combination of solar collector system and grid power. Results of this study show that the thermal energy rejected by an ARS of cooling capacity of 3.25 kW (0.975 tons of refrigeration) along with an additional energy input of 208 kJ/kg of desalinated water is adequate to produce desalinated water at an average rate of 4.5 kg/h. This energy consumption is competitive with that of the multi-stage flash distillation process of similar capacity (338 kJ/kg). An integrated process model and performance curves of the proposed approach are presented in this paper. Effects of process parameters on the performance of the system are also presented

  20. Hot air injection for removal of dense, non-aqueous-phase liquid contaminants from low-permeability soils

    Energy Technology Data Exchange (ETDEWEB)

    Payne, F.C.

    1996-08-01

    The performance of soil vapor extraction systems for the recovery of volatile and semi-volatile organic compounds is potentially enhanced by the injection of heated air to increase soil temperatures. The soil temperature increase is expected to improve soil vapor extraction (SVE) performance by increasing target compound vapor pressures and by increasing soil permeability through drying. The vapor pressure increase due to temperature rise relieves the vapor pressure limit on the feasibility of soil vapor extraction. However, the system still requires an air flow through the soil system to deliver heat and to recover mobilized contaminants. Although the soil permeability can be increased through drying, very low permeability soils and low permeability soils adjacent to high permeability air flow pathways will be treated slowly, if at all. AR thermal enhancement methods face this limitation. Heated air injection offers advantages relative to other thermal techniques, including low capital and operation costs. Heated air injection is at a disadvantage relative to other thermal techniques due to the low heat capacity of air. To be effective, heated air injection requires that higher air flows be established than for steam injection or radio frequency heating. Heated air injection is not economically feasible for the stratified soil system developed as a standard test for this document. This is due to the inability to restrict heated air flow to the clay stratum when a low-resistance air flow pathway is available in the adjoining sand. However, the technology should be especially attractive, both technically and economically, for low-volatile contaminant recovery from relatively homogeneous soil formations. 16 refs., 2 tabs.

  1. A combination of bioleaching and bioprecipitation for deep removal of contaminating metals from dredged sediment

    International Nuclear Information System (INIS)

    Highlights: → Bioleaching-bioprecipitation can deeply cleanup sediment-borne metal contaminants. → Bioleaching results in a sufficient solubilisation of sediment-borne metals. → Bioprecipitation removes most of solubilised metals from sediment leachate at pH 3.7. → Bioremoval of soluble Zn, Cu and Cr is due to the formation of ZnS, Cu2S and CrOOH. → Alkalization of bioleached sediment by Ca(OH)2 excludes the risk of re-acidification. - Abstract: A linked microbial process comprising bioleaching with sulfate-oxidizing bacteria and bioprecipitation with sulfate-reducing bacteria operating sequentially was investigated to deeply remove contaminating metals from dredged sediment. The results showed that sediment bioleaching resulted in a sharp decrease in sediment pH from an initial pH ∼7.6 to pH ∼2.5 within 10-20 days, approximately 65% of the main heavy metals present (Zn + Cu + Cr) were solubilized, and most of the unsolubilized metals existed in residual form of sediment. The acidic leachate that resulted from sediment bioleaching was efficiently stripped of metal sulfates using a bioprecipitation reactor when challenged with influent as low as pH ∼3.7. More than 99% of Zn2+, 99% of Cu2+ and 90% of Cr3+ were removed from the leachate, respectively, due to the formation of ZnS, Cu2S and CrOOH precipitates, as confirmed by SEM-EDS and XRD detection. It was also found that alkalization of bioleached sediment using Ca(OH)2 excluded the risk of sediment re-acidification. The ability of the combined process developed in this study to deeply remove heavy metals in insoluble sulfides or hydroxides forms makes it particularly attractive for the treatment of different types of metal contaminants.

  2. A combination of bioleaching and bioprecipitation for deep removal of contaminating metals from dredged sediment

    Energy Technology Data Exchange (ETDEWEB)

    Fang Di, E-mail: dfang@ouc.edu.cn [Department of Environmental Engineering, Ocean University of China, Qingdao 266100 (China); State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008 (China); Zhang Ruichang [Department of Environmental Engineering, Ocean University of China, Qingdao 266100 (China); Zhou Lixiang [Department of Environmental Engineering, Nanjing Agricultural University, Nanjing 210095 (China); Li Jie [Department of Environmental Engineering, Ocean University of China, Qingdao 266100 (China)

    2011-08-15

    Highlights: {yields} Bioleaching-bioprecipitation can deeply cleanup sediment-borne metal contaminants. {yields} Bioleaching results in a sufficient solubilisation of sediment-borne metals. {yields} Bioprecipitation removes most of solubilised metals from sediment leachate at pH 3.7. {yields} Bioremoval of soluble Zn, Cu and Cr is due to the formation of ZnS, Cu{sub 2}S and CrOOH. {yields} Alkalization of bioleached sediment by Ca(OH){sub 2} excludes the risk of re-acidification. - Abstract: A linked microbial process comprising bioleaching with sulfate-oxidizing bacteria and bioprecipitation with sulfate-reducing bacteria operating sequentially was investigated to deeply remove contaminating metals from dredged sediment. The results showed that sediment bioleaching resulted in a sharp decrease in sediment pH from an initial pH {approx}7.6 to pH {approx}2.5 within 10-20 days, approximately 65% of the main heavy metals present (Zn + Cu + Cr) were solubilized, and most of the unsolubilized metals existed in residual form of sediment. The acidic leachate that resulted from sediment bioleaching was efficiently stripped of metal sulfates using a bioprecipitation reactor when challenged with influent as low as pH {approx}3.7. More than 99% of Zn{sup 2+}, 99% of Cu{sup 2+} and 90% of Cr{sup 3+} were removed from the leachate, respectively, due to the formation of ZnS, Cu{sub 2}S and CrOOH precipitates, as confirmed by SEM-EDS and XRD detection. It was also found that alkalization of bioleached sediment using Ca(OH){sub 2} excluded the risk of sediment re-acidification. The ability of the combined process developed in this study to deeply remove heavy metals in insoluble sulfides or hydroxides forms makes it particularly attractive for the treatment of different types of metal contaminants.

  3. Wastewater micropollutants as tracers of sewage contamination: analysis of combined sewer overflow and stream sediments.

    Science.gov (United States)

    Hajj-Mohamad, M; Aboulfadl, K; Darwano, H; Madoux-Humery, A-S; Guérineau, H; Sauvé, S; Prévost, M; Dorner, S

    2014-01-01

    A sensitive method was developed to measure the sediment concentration of 10 wastewater micropollutants selected as potential sanitary tracers of sewage contamination and include: nonsteroidal anti-inflammatory drugs (acetaminophen - ACE and diclofenac - DIC), an anti-epileptic drug (carbamazepine - CBZ), a β-blocker (atenolol - ATL), a stimulant (caffeine - CAF), a bronchodilator (theophylline - THEO), steroid hormones (progesterone - PRO and medroxyprogesterone - MedP), an artificial sweetener (aspartame - APM) and personal care products (N,N-diethyl-3-methylbenzamide - DEET). Natural sediments (combined sewer overflow and stream sediments) were extracted by ultrasonic-assisted extraction followed by solid-phase extraction. Analyses were performed using ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) using atmospheric pressure chemical ionisation in positive mode (APCI+) with a total analysis time of 4.5 min. Method detection limits were in the range of 0.01 to 15 ng g(-1) dry weight (dw) for the compounds of interest, with recoveries ranging from 75% to 156%. Matrix effects were observed for some compounds, never exceeding |±18%|. All results displayed a good degree of reproducibility and repeatability, with relative standard deviations (RSD) of less than 23% for all compounds. The method was applied to an investigation of stream and combined sewer overflow sediment samples that differed in organic carbon contents and particle size distributions. Acetaminophen, caffeine and theophylline (as confounded with paraxanthine) were ubiquitously detected at 0.13-22 ng g(-1) dw in stream bed sediment samples and 98-427 ng g(-1) dw in combined sewer overflow sediment samples. Atenolol (80.5 ng g(-1) dw) and carbamazepine (54 ng g(-1) dw) were quantified only in combined sewer overflow sediment samples. The highest concentrations were recorded for DEET (14 ng g(-1) dw) and progesterone (11.5 ng g(-1) dw) in stream bed and combined

  4. A combined air cycle used for IC engine supercharging based on waste heat recovery

    International Nuclear Information System (INIS)

    Highlights: • A combined air cycle is proposed for IC engine supercharging based on WHR. • Cycle efficiency and energy recovery efficiency depend largely on working pressure. • Exhaust gas pressure of IC engine with combined air cycle is reduced largely. • IC engine fuel efficiency can be increased by 4.1% points at most. - Abstract: A combined air cycle is designed for internal combustion (IC) engine supercharging, which consists of IC engine working cycle and bottom cycle of waste heat recovery (WHR). The bottom cycle uses IC engine exhaust gas as cycle heat source, and its output power is used to drive the gas compressor. Both the heat transfer and thermodynamic processes of combined air cycle were investigated by numerical calculation under various cycle parameters and IC engine operating conditions. On this basis, the performances of combined air cycle and the improvement to IC engine performances were analyzed. Results show that, the cycle efficiency and exhaust gas energy recovery efficiency depend largely on the working pressure, and their maximum values appear at the working pressure of 0.35 MPa and 0.2 MPa, respectively. Compared with the naturally aspirated (NA) engine and turbocharging engine, this approach can make the fuel utilization efficiency of IC engine increase by 8.9% points and 4.1% points at most, respectively, due to the reduction of exhaust gas pressure. All these demonstrate that the proposed concept is a potentially useful approach for IC engine energy saving

  5. Treatment of Perchlorate-Contaminated Groundwater Using Highly-Selective, Regenerable Anion-Exchange Resins at Edwards Air Force Base

    Energy Technology Data Exchange (ETDEWEB)

    Gu, B.

    2003-05-30

    Selective ion exchange is one of the most effective treatment technologies for removing low levels of perchlorate (ClO{sub 4}{sup -}) from contaminated water because of its high efficiency without adverse impacts on the water quality caused by adding or removing any chemicals or nutrients. This report summarizes both the laboratory and a field pilot-scale studies to determine the ability and efficiency of the bifunctional synthetic resins to remove ClO{sub 4}{sup -} from the contaminated groundwater at the Edwards Air Force Base in California. Regeneration of the resins after groundwater treatment was also evaluated using the FeCl{sub 3}-HCl regeneration technique recently developed at Oak Ridge National Laboratory. On the basis of this study, the bifunctional resin, D-3696 was found to be highly selective toward ClO{sub 4}{sup -} and performed much better than one of the best commercial nitrate-selective resins (Purolite A-520E) and more than an order of magnitude better than the Purolite A-500 resin (with a relatively low selectivity). At an influent concentration of {approx} 450 {micro}g/L ClO{sub 4}{sup -} in groundwater, the bifunctional resin bed treated {approx} 40,000 empty bed volumes of groundwater before a significant breakthrough of ClO{sub 4}{sup -} occurred. The presence of relatively high concentrations of chloride and sulfate in site groundwater did not appear to affect the ability of the bifunctional resin to remove ClO{sub 4}{sup -}. However, the presence of high iron or iron oxyhydroxides and/or biomass in groundwater caused a significant fouling of the resin beds and greatly influenced the effectiveness in regenerating the resins sorbed with ClO{sub 4}{sup -}. Under such circumstances, a prefilter ({approx} 0.5-1 {micro}m) was found to be necessary to remove these particulates and to reduce the risk of fouling of the resin beds. Without significant fouling, the resin bed could be effectively regenerated by the FeCl{sub 3} displacement technique

  6. COMBINED EFFECT OF WATER CONTAMINATION WITH COBALT AND NICKEL ON METABOLISM OF ALBINO (WISTAR RATS

    Directory of Open Access Journals (Sweden)

    Z. Kechrid, F. Dahdouh, R. M. Djabar, N. Bouzerna

    2006-01-01

    Full Text Available The contamination of water by metal compounds is a worldwide environmental problem. Concentration of metals is widely related to biochemical values, which are used in diseases diagnosis due to environmental toxicity. The sub-chronic combined effects of nickel and cobalt on body weight gain and biochemical parameters were determined and compared with those of Ni (2+ or Co (2+ alone in 6 weeks male albino (Wistar rats. Animals were given drinking solutions of NiSO4 6H2O [Ni (II cation, LD50/2] or CoSO4 6H2O [Co (II cation, LD50/2]. For the combined treatment (Ni + Co, the rats received both Ni (II cation (LD 50/2 and CO (II cation (LD50/2. Nickel and cobalt treatment decreased body weight gain. The nickel sulphate increased also the glucose level. The two heavy elements produced hepatic and renal damage, characterized by increased activity of alanine and aspartate transaminases (GPT, GOT and alkaline phosphatase. However lactate dehydrogenase activity (LDH was decreased. In addition, serum urea, serum creatinine, serum total protein and serum bilurebin concentrations were significantly elevated. In general the combined effect of Ni-Co was slightly less toxic than nickel or cobalt alone, suggesting antagonism between these toxicants.

  7. Combined effect of radiation and environmental contaminants on DNA repair mechanisms

    International Nuclear Information System (INIS)

    Investigations on the influence of various environmental contamination agents on DNA repair (in combination with irradiation) were reviewed. The agents tested were: detergents (Tween 80, Nonidel P40, Cremophor), aflatoxin B1, furocumarines, drugs (indometacin, cyclophosphamide, vincristine, vinblastine, procarbacine), fluorides, irradiated food constituents, food additives (saccharin), metal ions (Cd, Hg), pesticides (2,4,5-trichlorophenoxyethanol) and infective agents (mycoplasmas). Most of the tests were carried out in vitro with γ-irradiated mouse spleen cells. The detergents and aflatoxin were tested also on E. coli, and irradiated glucose solutions were tested in vivo on Swiss albino mice injected with Salmonella typhimurium TA 1530. Most of the tested agents showed some kind of inhibitory or mutagenic effect. The experiments and results are explained briefly with references to earlier investigations

  8. Experimental study of a combined system of solar Kang and solar air collector

    International Nuclear Information System (INIS)

    Highlights: • A combined system of solar Kang and solar air collector is proposed. • An experimental study on the combined system is made. • The mean air temperature reaches 18.5 °C and maintains above 18 °C for 13 h. • The corresponding mean indoor air temperature of the reference room is 8.9 °C. • The Kang surface temperature reaches 27 °C and maintains above 18 °C for 23 h. - Abstract: Chinese Kang is widely used as heated bed and for heat recovery of cooking stove in Northern China. However there are main drawbacks of indoor and outdoor air pollutant generation and heavy demands on solid fuel handling. A novel combined Kang system, which integrates solar Kang and solar air collector, is here proposed. Experiments were conducted to examine the alternative operating modes: (i) only solar air collector in service, (ii) only solar Kang in service, and (iii) both solar Kang and solar air collector in service. The results show that these three modes behave differently and have distinct effects on room thermal environment in winter. When this pollution-free system operates under the third combined mode, the room temperature increases significantly and the vertical temperature gradient reduces. The Kang surface temperature increases and its uniformity is improved. It is also found that the room air temperature is closely related to the Kang surface temperature. Furthermore, most of the time the thermal environment meets the occupant need. This paper reports the experimental work and investigates into the effects on indoor thermal environment as in rural residences in Northern China

  9. Analysis of Steam Condensation in a Finned Tube of Air-Water Combined Cooling System

    Energy Technology Data Exchange (ETDEWEB)

    Kwon, Taesoon; Bae, S. W.; Kim, K. H.; Park, Y. S.; Park, H. S. [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2014-05-15

    A Passive Auxiliary Feedwater System (PAFS) is one of the passive cooling systems of the existing power plant and the operating period is 8 hours because of the limited capacity of the cooling water tank. Therefore, to increase the operating period from 8 to 72 hours for an existing PAFS, the capacity of the cooling water tank should be increased up to 3-4 times. To resolve the excessive increase of the cooling tank volume in water cooling systems, an air-water combined passive cooling system is proposed. In this combined cooling system, the core cooling during the initial stage of an accident having high decay power depends on the water cooling systems such as PAFS. For the later phase of an accident, an air-cooling system is applied to the core cooling. In the operation of the air-cooling system, the steam from the cooling water tank of the PAFS is condensed and recirculated to the cooling water tank by an air-cooling heat exchanger. In this way, the increase of the cooling water tank volume can be minimized. To design an air-water combined cooling system, the steam condensation characteristics of an air-cooling heat exchanger tube was calculated using a CFX code. The results show that the air velocities around the tube at the steam inlet/outlet regions are quite different with each other. Therefore, dense installation of thermocouples at the tube bottom region is required to measure the steam condensation in the tube. Otherwise, the detection and measurement of steam condensation at the steam inlet region may be very difficult. The velocity distribution of air is not uniform and the distributions of air temperature and velocity around the heat exchanger tube are strongly asymmetric. In the design of the measurement system of the test facility, the problems mentioned above should be considered.

  10. Analysis of Steam Condensation in a Finned Tube of Air-Water Combined Cooling System

    International Nuclear Information System (INIS)

    A Passive Auxiliary Feedwater System (PAFS) is one of the passive cooling systems of the existing power plant and the operating period is 8 hours because of the limited capacity of the cooling water tank. Therefore, to increase the operating period from 8 to 72 hours for an existing PAFS, the capacity of the cooling water tank should be increased up to 3-4 times. To resolve the excessive increase of the cooling tank volume in water cooling systems, an air-water combined passive cooling system is proposed. In this combined cooling system, the core cooling during the initial stage of an accident having high decay power depends on the water cooling systems such as PAFS. For the later phase of an accident, an air-cooling system is applied to the core cooling. In the operation of the air-cooling system, the steam from the cooling water tank of the PAFS is condensed and recirculated to the cooling water tank by an air-cooling heat exchanger. In this way, the increase of the cooling water tank volume can be minimized. To design an air-water combined cooling system, the steam condensation characteristics of an air-cooling heat exchanger tube was calculated using a CFX code. The results show that the air velocities around the tube at the steam inlet/outlet regions are quite different with each other. Therefore, dense installation of thermocouples at the tube bottom region is required to measure the steam condensation in the tube. Otherwise, the detection and measurement of steam condensation at the steam inlet region may be very difficult. The velocity distribution of air is not uniform and the distributions of air temperature and velocity around the heat exchanger tube are strongly asymmetric. In the design of the measurement system of the test facility, the problems mentioned above should be considered

  11. A Humid Air Turbine–Organic Rankine Cycle combined cycle for distributed microgeneration

    International Nuclear Information System (INIS)

    Highlights: • Humid Air microTurbine and Organic Rankine Cycle models. • Micro combined cycle with optimized medium/low temperature heat recovery. • Thermodynamic analyses of different integrations, fluids and parameters. • Outstanding performance parameters in the distributed generation power range. • Economic analyses show the high viability of the proposed concept. - Abstract: This paper analyses the integration of Humid Air microturbine and an Organic Rankine Cycle in a combined cycle for distributed generation. This integration concept maximizes heat recovery at the exhaust of the micro gas turbine combining the capacities for medium temperature heat recovery of the Organic Rankine Cycle and low temperature heat recovery of the Humid Air Turbine. The integration analysis based on different sets of organic fluids and different recovery temperatures showed that the optimal combination was achieved using toluene and R245fa for medium and low temperature Organic Rankine Cycles respectively. Their combination with the low temperature heat recovery at the Humid Air Turbine saturator maximizes the heat recovery profile from the exhaust gases. The calculations carried out reveal a 25% improvement in net power output of the dual cycle compared to the standalone Humid Air microturbine. Such improvement also affects to global efficiency, increasing it up to 52% in the optimal configuration, above the 41% estimated for the standalone Humid Air Turbine and the 33% rated efficiency of the state of art microturbine Capstone C200. The economic analysis shows that these increases in efficiency and power values make the proposed concept highly competitive, with a 15% reduction in the Levelized Cost of Electricity compared with the standalone Humid Air Turbine and a reduction of 30% compared with the micro gas turbine base case. The presented results show this novel integration as a very promising solution for distributed generation applications at power range under

  12. [Environmental investigation of ground water contamination at Wright-Patterson Air Force Base, Ohio

    International Nuclear Information System (INIS)

    This Removal Action System Design has been prepared as a Phase I Volume for the implementation of the Phase II removal action at Wright-Patterson Air Force Base (WPAFB) near Dayton, Ohio. The objective of the removal action is to prevent, to the extent practicable, the migration of ground water contaminated with chlorinated volatile organic compounds (VOCS) across the southwest boundary of Area C. The Phase 1, Volume 9 Removal Action System Design compiles the design documents prepared for the Phase II Removal Action. These documents, which are presented in Appendices to Volume 9, include: Process Design, which presents the 30 percent design for the ground water treatment system (GWTS); Design Packages 1 and 2 for Earthwork and Road Construction, and the Discharge Pipeline, respectively; no drawings are included in the appendix; Design Package 3 for installation of the Ground Water Extraction Well(s); Design Package 4 for installation of the Monitoring Well Instrumentation; and Design Package 5 for installation of the Ground Water Treatment System; this Design Package is incorporated by reference because of its size

  13. Utilization of air pollution control residues for the stabilization/solidification of trace element contaminated soil.

    Science.gov (United States)

    Travar, I; Kihl, A; Kumpiene, J

    2015-12-01

    The aim of this study was to evaluate the stabilization/solidification (S/S) of trace element-contaminated soil using air pollution control residues (APCRs) prior to disposal in landfill sites. Two soil samples (with low and moderate concentrations of organic matter) were stabilized using three APCRs that originated from the incineration of municipal solid waste, bio-fuels and a mixture of coal and crushed olive kernels. Two APCR/soil mixtures were tested: 30% APCR/70% soil and 50% APCR/50% soil. A batch leaching test was used to study immobilization of As and co-occurring metals Cr, Cu, Pb and Zn. Solidification was evaluated by measuring the unconfined compression strength (UCS). Leaching of As was reduced by 39-93% in APCR/soil mixtures and decreased with increased amounts of added APCR. Immobilization of As positively correlated with the amount of Ca in the APCR and negatively with the amount of soil organic matter. According to geochemical modelling, the precipitation of calcium arsenate (Ca3(AsO4)2/4H2O) and incorporation of As in ettringite (Ca6Al2(SO4)3(OH)12 · 26H2O) in soil/APCR mixtures might explain the reduced leaching of As. A negative effect of the treatment was an increased leaching of Cu, Cr and dissolved organic carbon. Solidification of APCR/soil was considerably weakened by soil organic matter. PMID:26233740

  14. Bilirubin oxidase based enzymatic air-breathing cathode: Operation under pristine and contaminated conditions.

    Science.gov (United States)

    Santoro, Carlo; Babanova, Sofia; Erable, Benjamin; Schuler, Andrew; Atanassov, Plamen

    2016-04-01

    The performance of bilirubin oxidase (BOx) based air breathing cathode was constantly monitored over 45 days. The effect of electrolyte composition on the cathode oxygen reduction reaction (ORR) output was investigated. Particularly, deactivation of the electrocatalytic activity of the enzyme in phosphate buffer saline (PBS) solution and in activated sludge (AS) was evaluated. The greatest drop in current density was observed during the first 3 days of constant operation with a decrease of ~60 μA cm(-2) day(-1). The rate of decrease slowed to ~10 μA cm(-2) day(-1) (day 3 to 9) and then to ~1.5 μA cm(-2)day(-1) thereafter (day 9 to 45). Despite the constant decrease in output, the BOx cathode generated residual current after 45 days operations with an open circuit potential (OCP) of 475 mV vs. Ag/AgCl. Enzyme deactivation was also studied in AS to simulate an environment close to the real waste operation with pollutants, solid particles and bacteria. The presence of low-molecular weight soluble contaminants was identified as the main reason for an immediate enzymatic deactivation within few hours of cathode operation. The presence of solid particles and bacteria does not affect the natural degradation of the enzyme. PMID:26544631

  15. (Environmental investigation of ground water contamination at Wright-Patterson Air Force Base, Ohio)

    Energy Technology Data Exchange (ETDEWEB)

    1992-04-01

    This Removal Action System Design has been prepared as a Phase I Volume for the implementation of the Phase II removal action at Wright-Patterson Air Force Base (WPAFB) near Dayton, Ohio. The objective of the removal action is to prevent, to the extent practicable, the migration of ground water contaminated with chlorinated volatile organic compounds (VOCS) across the southwest boundary of Area C. The Phase 1, Volume 9 Removal Action System Design compiles the design documents prepared for the Phase II Removal Action. These documents, which are presented in Appendices to Volume 9, include: Process Design, which presents the 30 percent design for the ground water treatment system (GWTS); Design Packages 1 and 2 for Earthwork and Road Construction, and the Discharge Pipeline, respectively; no drawings are included in the appendix; Design Package 3 for installation of the Ground Water Extraction Well(s); Design Package 4 for installation of the Monitoring Well Instrumentation; and Design Package 5 for installation of the Ground Water Treatment System; this Design Package is incorporated by reference because of its size.

  16. Forecast of common air contaminants in Alberta (1995 to 2020) : Final report

    International Nuclear Information System (INIS)

    In this document, a distinction is made between anthropogenic sources (industrial, residential, commercial, institutional, transportation, and area sources) and natural sources (forest fires and biogenic sources). Nitrogen oxides, sulphur oxides and carbon monoxide are caused by both sources, but their ratio varies. The emphasis of this report was on the growth in anthropogenic emissions in Alberta from industrial sources. For the purpose of this forecast, the natural sources were kept constant at 1995 levels. An inventory of common air contaminants (CAC) in Alberta was obtained in 1995 and formed the starting point of this forecast. Under business as usual scenario, CAC emissions in Alberta are expected to increase. The increase is expected to be in the 18 per cent range by 2010 and 32 per cent range by 2020 over the levels of 1995. Anticipated energy efficiency improvements, as well as a shift toward less CAC-intensive fuels like natural gas explain this slower growth. In the context of improved vehicle emission standards, reduced emissions from transportation were anticipated. There are wide differences for the magnitude of the projected change for each of the CACs. The greatest increase was forecasted for total particulate emissions caused in large part by road dust. A decrease was forecasted for sulphur oxides and carbon monoxide emissions as a result of improved fuel and vehicle emission standards. For each of Alberta's 19 census divisions or regions, estimates of forecasted 2010 emissions from each source category were included. 24 refs., 77 tabs

  17. Contamination mechanisms of air basin with tritium in venues of underground nuclear explosions at the former Semipalatinsk test site

    International Nuclear Information System (INIS)

    During the period of testing from 1945 to 1962 at the territory of Semipalatinsk test site (STS) within the Degelen Mountains in tunnels, 209 underground nuclear explosions were produced. Many of the tunnels have seasonal water seepage in the form of streams, through which tritium migrates from the underground nuclear explosion (UNE) venues towards the surface. The issue of tritium contamination occupies a special place in the radioactive contamination of the environment. In this paper we assess the level and distribution of tritium in the atmospheric air of ecosystems with water seepage at tunnels № 176 and № 177, located on “Degelen” site. There has been presented general nature of tritium distribution in the atmosphere relative to surface of a watercourse which has been contaminated with tritium. The basic mechanisms were studied for tritium distribution in the air of studied ecosystems, namely, the distribution of tritium in the systems: water–atmosphere, tunnel air–atmosphere, soil water–atmosphere, vegetation–atmosphere. An analytical calculation of tritium concentration in the atmosphere by the concentration of tritium in water has been performed. There has experimentally obtained the dependence for predictive assessment of tritium concentrations in air as a function of tritium concentration in one of the inlet sources such as water, tunnel air, soil water, vegetation, etc.. The paper also describes the general nature of tritium distribution in the air in the area “Degelen”. - Highlights: ► The basic mechanisms for tritium distribution in the air of nuclear testing sites were examined. ► We researched the distribution of tritium in the systems such as water–atmosphere, tunnel air–atmosphere, soil water–atmosphere and vegetation–atmosphere. ► An analytical calculation of tritium concentration in the atmosphere was performed. ► We experimentally obtained the dependence for predictive assessment of tritium concentrations in

  18. The shame of contaminated air: enquiry about the years 2000 pollution; Le scandale de l'air contamine: enquete sur la pollution des annees 2000

    Energy Technology Data Exchange (ETDEWEB)

    Tarnier, Ph.

    2001-07-01

    This book reports on a personal enquiry carried out by the author (testimonies, independent scientific works etc..) and which contradicts the reassuring 'official' reports about the air quality of urban areas. (J.S.)

  19. Status of environmental response efforts at radioactively contaminated sites in the united states air force installation restoration program

    International Nuclear Information System (INIS)

    The United States Air Force has identified approximately 170 radioactively contaminated sites at its domestic installations. These sites contain a variety of low level radioactive and mixed wastes and are classified as burial sites, landfills, buildings, and other disposal sites. Of these 170, approximately 70 are presently being evaluated under the Air Force Installation Restoration Program (IRP) in accordance with applicable laws and regulations. Removal and/or remedial actions have been taken at specific sites using site-specific residual radioactivity criteria. The remaining sites are either under investigation to determine the need for possible action or have been classified as response complete based on restricted or unrestricted future use. This paper describes past Air Force operations that generated radioactive waste materials; examines the current inventory of resulting radioactively contaminated sites in the Air Force IRP; reviews criteria used to evaluate sites for removal and/or remedial actions; provides summary information on actions taken at sites; and focuses on response actions and cleanup levels at two completed sites. The paper concludes with an assessment of outstanding issues relevant to the remediation of radioactively contaminated sites. (author)

  20. Pump combiner for air-clad fiber with PM single-mode signal feed-through

    DEFF Research Database (Denmark)

    Noordegraaf, Danny; Nielsen, Martin D.; Skovgaard, Peter M.W.;

    2009-01-01

    A pump combiner with single-mode PM signal feed-through designed for an air-clad photonic crystal fiber is demonstrated. Signal coupling is realized by a novel taper element allowing single-mode guidance at a taper ratio of 3.7.......A pump combiner with single-mode PM signal feed-through designed for an air-clad photonic crystal fiber is demonstrated. Signal coupling is realized by a novel taper element allowing single-mode guidance at a taper ratio of 3.7....

  1. Comparative Studies on Methane Upgradation of Biogas by Removing of Contaminant Gases Using Combined Chemical Methods

    Directory of Open Access Journals (Sweden)

    Muhammad Rashed Al Mamun

    2015-07-01

    Full Text Available Biogas, which generated from renewable sources can be used as a sustainable energy to achieve resourceful targets of biofuel for internal combustion engines. This process can be achieved in combined absorption and adsorption chemical way. This method can be employed by aqueous solutions of calcium hydroxide, activated carbon, iron(II chloride, silica gel and sodium sulfate respectively. The presence of CO2, H2S and H2O in the biogas has lowering the calorific value and detrimental corrosion effects on the metal components. Removal of these contaminants from the biogas can therefore significantly improve the gas quality. A comparison study was investigated using combined chemical methods of improving the calorific value of biogas. Experiment results revealed that the aqueous solution used effectively in reacting with CO2 in biogas (over 85-90% removal efficiency, creating CH4 enriched biogas. The removal efficiency was the highest in method 1, where efficiency results were 91.5%, 97.1% and 91.8%, for CO2, H2S, and H2O, respectively. The corresponding CH4 enrichment was 97.5%. These results indicate that the method 1 is more suitable compare to method 2. However, both methane enrichment processes might be useful for cleaning and upgrading methane quality in biogas.

  2. Comparison of Air Impaction and Electrostatic Dust Collector Sampling Methods to Assess Airborne Fungal Contamination in Public Buildings.

    Science.gov (United States)

    Normand, Anne-Cécile; Ranque, Stéphane; Cassagne, Carole; Gaudart, Jean; Sallah, Kankoé; Charpin, Denis-André; Piarroux, Renaud

    2016-03-01

    Many ailments can be linked to exposure to indoor airborne fungus. However, obtaining a precise measurement of airborne fungal levels is complicated partly due to indoor air fluctuations and non-standardized techniques. Electrostatic dust collector (EDC) sampling devices have been used to measure a wide range of airborne analytes, including endotoxins, allergens, β-glucans, and microbial DNA in various indoor environments. In contrast, viable mold contamination has only been assessed in highly contaminated environments such as farms and archive buildings. This study aimed to assess the use of EDCs, compared with repeated air-impactor measurements, to assess airborne viable fungal flora in moderately contaminated indoor environments. Indoor airborne fungal flora was cultured from EDCs and daily air-impaction samples collected in an office building and a daycare center. The quantitative fungal measurements obtained using a single EDC significantly correlated with the cumulative measurement of nine daily air impactions. Both methods enabled the assessment of fungal exposure, although a few differences were observed between the detected fungal species and the relative quantity of each species. EDCs were also used over a 32-month period to monitor indoor airborne fungal flora in a hospital office building, which enabled us to assess the impact of outdoor events (e.g. ground excavations) on the fungal flora levels on the indoor environment. In conclusion, EDC-based measurements provided a relatively accurate profile of the viable airborne flora present during a sampling period. In particular, EDCs provided a more representative assessment of fungal levels compared with single air-impactor sampling. The EDC technique is also simpler than performing repetitive air-impaction measures over the course of several consecutive days. EDC is a versatile tool for collecting airborne samples and was efficient for measuring mold levels in indoor environments. PMID:26491105

  3. Cumulative effects of fecal contamination from combined sewer overflows: Management for source water protection.

    Science.gov (United States)

    Jalliffier-Verne, Isabelle; Heniche, Mourad; Madoux-Humery, Anne-Sophie; Galarneau, Martine; Servais, Pierre; Prévost, Michèle; Dorner, Sarah

    2016-06-01

    The quality of a drinking water source depends largely on upstream contaminant discharges. Sewer overflows can have a large influence on downstream drinking water intakes as they discharge untreated or partially treated wastewaters that may be contaminated with pathogens. This study focuses on the quantification of Escherichia coli discharges from combined sewer overflows (CSOs) and the dispersion and diffusion in receiving waters in order to prioritize actions for source water protection. E. coli concentrations from CSOs were estimated from monitoring data at a series of overflow structures and then applied to the 42 active overflow structures between 2009 and 2012 using a simple relationship based upon the population within the drainage network. From these estimates, a transport-dispersion model was calibrated with data from a monitoring program from both overflow structures and downstream drinking water intakes. The model was validated with 15 extreme events such as a large number of overflows (n > 8) or high concentrations at drinking water intakes. Model results demonstrated the importance of the cumulative effects of CSOs on the degradation of water quality downstream. However, permits are typically issued on a discharge point basis and do not consider cumulative effects. Source water protection plans must consider the cumulative effects of discharges and their concentrations because the simultaneous discharge of multiple overflows can lead to elevated E. coli concentrations at a drinking water intake. In addition, some CSOs have a disproportionate impact on peak concentrations at drinking water intakes. As such, it is recommended that the management of CSOs move away from frequency based permitting at the discharge point to focus on the development of comprehensive strategies to reduce cumulative and peak discharges from CSOs upstream of drinking water intakes. PMID:27011341

  4. Evaluation of a Design Concept for the Combined Air-water Passive Cooling PAFS+

    Energy Technology Data Exchange (ETDEWEB)

    Bae, Sung Won; Kwon, Taesoon [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2014-05-15

    The APR+ system provides the Passive Auxiliary Feed-water System (PAFS) for the passive cooling capability. However, the current design requirement for working time for the PAFS is about 8 hours only. Thus, current working time of PAFS can not meet the required 72 hours cooling capability for the long term SBO situation. To meet the 72 hours cooling, the pool capacity should be almost 3∼4 times larger than that of current water cooling tank. In order to continue the PAFS operation for 72 hours, a new passive air-water combined cooling system is proposed. This paper provides the feasibility study on the combined passive air-water cooling system. Figure 1 and 2 show the conceptual difference of the PAFS and combined passive air-water cooling system, respectively. Simple performance evaluation of the passive air cooling heat exchanger has been conducted by the MARS calculation. For the postulated FLB scenario, 4800 heat exchanger tubes and 5 m/s air velocity are not sufficient to sustain the PCCT pool level for 72 hour cooling. Further works on the system design and performance enhancing plan are required to fulfill the 72 hours long term passive cooling.

  5. Evaluation of a Design Concept for the Combined Air-water Passive Cooling PAFS+

    International Nuclear Information System (INIS)

    The APR+ system provides the Passive Auxiliary Feed-water System (PAFS) for the passive cooling capability. However, the current design requirement for working time for the PAFS is about 8 hours only. Thus, current working time of PAFS can not meet the required 72 hours cooling capability for the long term SBO situation. To meet the 72 hours cooling, the pool capacity should be almost 3∼4 times larger than that of current water cooling tank. In order to continue the PAFS operation for 72 hours, a new passive air-water combined cooling system is proposed. This paper provides the feasibility study on the combined passive air-water cooling system. Figure 1 and 2 show the conceptual difference of the PAFS and combined passive air-water cooling system, respectively. Simple performance evaluation of the passive air cooling heat exchanger has been conducted by the MARS calculation. For the postulated FLB scenario, 4800 heat exchanger tubes and 5 m/s air velocity are not sufficient to sustain the PCCT pool level for 72 hour cooling. Further works on the system design and performance enhancing plan are required to fulfill the 72 hours long term passive cooling

  6. Integration of photocatalytic oxidation with air stripping of contaminated aquifers. Report for 1 October 1993--30 June 1997

    Energy Technology Data Exchange (ETDEWEB)

    Changrani, R.; Raupp, G.B.; Turchi, C.

    1998-12-01

    The global objective of this work was to evaluate the integration of gas-solid ultraviolet (UV) photocatalytic oxidation (PCO) downstream of an air stripper as a technology for cost-effectively treating water pumped from an aquifer contaminated with chlorinated volatile organic compounds (VOCs). Experimental work was performed at the bench-scale in the laboratory during the first phase of the project, and at the pilot-scale in a simulated field-test situation during the second phase.

  7. The frequency of chromosomal aberrations in sheep from the area contaminated by depleted uranium during NATO air strikes in 1999

    OpenAIRE

    Fišter Svetlana L.; Jović Slavoljub Z.

    2014-01-01

    This paper presents the results of cytogenetic studies in sheep from the region of Bujanovac that was contaminated by depleted uranium during the NATO air strikes in 1999. The study was conducted on sheep blood lymphocytes, in order to determine the frequency of chromosomal aberrations and to assess the presence of genetic risk as a result of the possible impact of depleted uranium. Blood samples for lymphocyte cultures were taken at random from the 20 anim...

  8. Combined Heat and Power: Coal-Fired Air Turbine (CAT)-Cycle Plant

    International Nuclear Information System (INIS)

    By combining an integrated system with a gas turbine, coal-fired air turbine cycle technology can produce energy at an efficiency rate of over 40%, with capital and operating costs below those of competing conventional systems. Read this fact sheet to discover the additional benefits of this exciting new technology

  9. A combination of hot air and methyl jasmonate vapor treatment alleviates chilling injury of peach fruit

    Science.gov (United States)

    Peaches were harvested at firm-mature stage and treated with various combinations of methyl jasmonate (MeJA) and hot air. Severity of internal browning and flesh mealiness, firmness, extractable juice rate, total soluble solids (TSS), total acid, vitamin C and total phenolic contents were measured a...

  10. The Contaminant Distribution in a Ventilated Room with Different Air Terminal Devices

    OpenAIRE

    Heiselberg, Per; Nielsen, Peter V.

    1987-01-01

    The room ventilation is investigated for three different air terminal devices under isothermal conditions.Velocity distribution in the occupied zone is measured for each air terminal device at different air exchange rates. The maximum air exchange rate is determined on the base of both the throw of the jets and the comfort requirements applied to measured air velocities in the occupied zone.Normalized concentration distribution in the test room is determined along a vertical line through the ...

  11. Operational Limitations for Demolition of a Highly Alpha-Contaminated Building ? Modeled Versus Measured Air and Surface Activity Concentrations

    International Nuclear Information System (INIS)

    The demolition of a facility historically used for processing and handling transuranic materials is considered. Residual alpha-emitting radionuclide contamination poses an exposure hazard if released to the local environment during the demolition. The process of planning for the demolition of this highly alpha-contaminated building, 232-Z, included a pre-demolition modeling analysis of potential exposures. Estimated emission rates were used as input to an air dispersion model to estimate frequencies of occurrence of peak air and surface exposures. Post-demolition modeling was also conducted based on the actual demolition schedule and conditions. The modeling results indicated that downwind deposition is the main operational limitation for demolition of a highly alpha-contaminated building. During the demolition of the 232-Z, airborne radiation and surface contamination were monitored. The resultant non-detect monitoring results indicate a significant level of conservatism in the modeled results. This comparison supports the use of more realistic assumption in the estimation of emission rates. The resultant reduction in modeled levels of potential exposures has significant implications in terms of the projected costs of demolition of such structures

  12. OPERATIONAL LIMITATIONS FOR DEMOLITION OF A HIGHLY ALPHA-CONTAMINATED BUILDING- MODELED VERSUS MEASURED AIR and SURFACE ACTIVITY CONCENTRATIONS

    International Nuclear Information System (INIS)

    The demolition of a facility historically used for processing and handling transuranic materials is considered. Residual alpha emitting radionuclide contamination poses an exposure hazard if released to the local environment during the demolition. The process of planning for the demolition of this highly alpha contaminated building, 232-Z, included a predemolition modeling analysis of potential exposures. Estimated emission rates were used as input to an air dispersion model to estimate frequencies of occurrence of peak air and surface exposures. Postdemolition modeling was also conducted, based on the actual demolition schedule and conditions. The modeling results indicated that downwind deposition is the main operational limitation for demolition of a highly alpha-contaminated building. During the demolition of 232-Z, airborne radiation and surface contamination were monitored. The resultant non-detect monitoring results indicate a significant level of conservatism in the modeled results. This comparison supports the use of more realistic assumption in the estimating emission rates. The resultant reduction in modeled levels of potential exposures has significant implications in terms of the projected costs of demolition of such structures

  13. Predicting soil, water, and air concentrations of environmental contaminants locally and regionally: Multimedia transport and transformation models

    International Nuclear Information System (INIS)

    Environmental scientists recognize that the environment functions as a complex, interconnected system. A realistic risk-management strategy for many contaminants requires a comprehensive and integrated assessment of local and regional transport and transformation processes. In response to this need, we have developed multimedia models that simulate the movement and transformation of chemicals as they spread through air, water, biota, soils, sediments, surface water, and ground water. Each component of the environment is treated as a homogeneous subsystem that can exchange water, nutrients, and chemical contaminants with other adjacent compartments. In this paper, we illustrate the use of multimedia models and measurements as tools for screening the potential risks of contaminants released to air and deposited onto soil and plants. The contaminant list includes the volatile organic compounds (VOCs) tetrachloroethylene (PCE) and trichloroethylene (TCE), the semi-volatile organic compound benzo(a)pyrene, and the radionuclides tritium and uranium-238. We examine how chemical properties effect both the ultimate route and quantity of human and ecosystem contact and identify sensitivities and uncertainties in the model results

  14. CAirTOX, An inter-media transfer model for assessing indirect exposures to hazardous air contaminants

    International Nuclear Information System (INIS)

    Risk assessment is a quantitative evaluation of information on potential health hazards of environmental contaminants and the extent of human exposure to these contaminants. As applied to toxic chemical emissions to air, risk assessment involves four interrelated steps. These are (1) determination of source concentrations or emission characteristics, (2) exposure assessment, (3) toxicity assessment, and (4) risk characterization. These steps can be carried out with assistance from analytical models in order to estimate the potential risk associated with existing and future releases. CAirTOX has been developed as a spreadsheet model to assist in making these types of calculations. CAirTOX follows an approach that has been incorporated into the CalTOX model, which was developed for the California Department of Toxic Substances Control, With CAirTOX, we can address how contaminants released to an air basin can lead to contamination of soil, food, surface water, and sediments. The modeling effort includes a multimedia transport and transformation model, exposure scenario models, and efforts to quantify uncertainty in multimedia, multiple-pathway exposure assessments. The capacity to explicitly address uncertainty has been incorporated into the model in two ways. First, the spreadsheet form of the model makes it compatible with Monte-Carlo add-on programs that are available for uncertainty analysis. Second, all model inputs are specified in terms of an arithmetic mean and coefficient of variation so that uncertainty analyses can be carried out

  15. Thermodynamic assessment of impact of inlet air cooling techniques on gas turbine and combined cycle performance

    International Nuclear Information System (INIS)

    The article is focused on the comparison of impact of two different methods of inlet air cooling (vapor compression and vapor absorption cooling) integrated to a cooled gas turbine based combined cycle plant. Air-film cooling has been adopted as the cooling technique for gas turbine blades. A parametric study of the effect of compressor pressure ratio, compressor inlet temperature (Ti,C), turbine inlet temperature (Ti,T), ambient relative humidity and ambient temperature on performance parameters of plant has been carried out. Optimum Ti,T corresponding to maximum plant efficiency of combined cycle increases by 100 °C due to the integration of inlet air cooling. It has been observed that vapor compression cooling improves the efficiency of gas turbine cycle by 4.88% and work output by 14.77%. In case of vapor absorption cooling an improvement of 17.2% in gas cycle work output and 9.47% in gas cycle efficiency has been observed. For combined cycle configuration, however, vapor compression cooling should be preferred over absorption cooling in terms of higher plant performance. The optimum value of compressor inlet temperature has been observed to be 20 °C for the chosen set of conditions for both the inlet air cooling schemes. - Highlights: • Inlet air cooling improves performance of cooled gas turbine based combined cycle. • Vapor compression inlet air cooling is superior to vapor absorption inlet cooling. • For every turbine inlet temperature, there exists an optimum pressure ratio. • The optimum compressor inlet temperature is found to be 293 K

  16. Effect of sample digestion, air filter contamination, and post-adsorption on the analysis of trace elements in air particulate matter

    International Nuclear Information System (INIS)

    Inductively coupled plasma atomic emission spectrometry and inductively coupled plasma MS are the major analytical tools for trace elements in environmental matrices, however, the underestimate of certain trace elements in analysis of air particulate matter by these two techniques has long been observed. This has been attributed to incomplete sample digestion. Here, we demonstrate that the combined effects of sample digestion, air filter impurities, and post-adsorption of the analytes contribute to the interference of the analysis. Particular attention should be paid to post-adsorption of analytes onto air filters after acid digestion. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  17. Predictive contamination of animal products due to the inhalation of air and the ingestion of soil of cattle in an accidental release of radioactive materials. Focusing on contaminative influence of milk

    International Nuclear Information System (INIS)

    In an accidental release of radioactive materials to the environment, the contaminative influence of animal products due to the inhalation of air and the ingestion of soil of cattle, both of which are considered as minor contaminative pathways in most radioecological models but may be important ones, was investigated with the improvement of the Korean radioecological model DYNACON. Although mathematical models for both contaminative pathways have been established for considering all animal products and incorporated into the model, investigation was limited to milk. As a result, it was found that both pathways are influential in the contamination of milk during the non-grazing period of dairy cows. Precipitation was an influential factor in milk contamination due to the ingestion of soil, especially for 137Cs. In the case of an accidental release during the grazing period of dairy cows, the contaminative influence due to the inhalation of air was negligible irrespective of the existence of precipitation during an accidental release. (author)

  18. Contamination by cadmium and lead of some fruits and vegetables exposed to polluted air

    International Nuclear Information System (INIS)

    Author.Global air pollution and particularly in the urban cities derives from vehicle transportation (cars, buses, trucks) and electric generators. In Lebanon, many people use fuel diesel and leaded gasoline in the engines of their vehicles. Indeed, the fuel used in our country, contains thirteen times more pollutants than that used legally in the developed countries (Magazine de l'environnement, 2002). This contributes to the pollution of the air that we breathe as well as the fruits and vegetables exposed to air. 762 samples of four kinds of different fruits (peaches, apples, strawberries and grapes) and two kinds of vegetables (parsleys and cucumbers) were taken twice and during different periods from eight different places in laps of time of seven days. The samples were analyzed in the laboratories of IRAL at Fanar and Tal-Amara, using the Spectroscopy Atomic Absorption method. The analysis included two groups of samples: the first one comprises 192 samples of fruits and vegetables without peeling and the second one comprises 570 samples of fruit and vegetables with peeling. The average values of the non washed samples were between 0.13 ±0.012 and 0.6 ppm ± 0.02 for lead and 0.06 ± 0.015 and 0.18 ppm ± 0.02 for cadmium. Those of the non washed peelings were between 0.08 ± 0.015 and 0.38 ppm ±0.025 for lead and 0.03 ±0.006 and 0.11 ppm ± for cadmium. On the other hand, those of the non-washed peeled samples were between 0.05 ± 0.01 and 0.27 ppm ± 0.016 for lead and 0.03 ± 0.016 and lead and 0.03 ± 0.06 and 0.07 ppm ± 0.015 for cadmium. Once these samples were washed , the average values were marked between 0.03 ± 0.006 and 0.15 ppm ± 0.02 for the lead and 0.02 ± 0.006 and 0.06 ppm ± 0.015 for the cadmium. Then, after drying them, concentrations revealed to be comprised between 0.02 ± 0.005 and 0.1 ppm ± 0.02 for the lead and 0.01 and 0.04 ppm ± 0.006 for the cadmium and that of the washing water was concentrated between 0.09 ± 0.016 and 0

  19. Electrical Characteristics, Electrode Sheath and Contamination Layer Behavior of a Meso-Scale Premixed Methane-Air Flame Under AC/DC Electric Fields

    Science.gov (United States)

    Chen, Qi; Yan, Limin; Zhang, Hao; Li, Guoxiu

    2016-05-01

    Electrical characteristics of a nozzle-attached meso-scale premixed methane-air flame under low-frequency AC (0-4300 V, 0-500 Hz) and DC (0-3300 V) electric fields were studied. I-V curves were measured under different experimental conditions to estimate the magnitude of the total current 100-102 μA, the electron density 1015-1016 m‑3 and further the power dissipation ≤ 0.7 W in the reaction zone. At the same time, the meso-scale premixed flame conductivity 10‑4-10‑3 Ω‑1·m‑1 as a function of voltage and frequency was experimentally obtained and was believed to represent a useful order-of magnitude estimate. Moreover, the influence of the collision sheath relating to Debye length (31–98 μm) and the contamination layer of an active electrode on measurements was discussed, based on the combination of simulation and theoretical analysis. As a result, the electrode sheath dimension was evaluated to less than 0.5 mm, which indicated a complex effect of the collision sheath on the current measurements. The surface contamination effect of an active electrode was further analyzed using the SEM imaging method, which showed elements immigration during the contamination layer formation process. supported by National Natural Science Foundation of China (No. 51376021), and the Fundamental Research Fund for Major Universities (No. 2013JBM079)

  20. Development and validation of a high-throughput liquid-absorption preconcentrator for the detection of trace air contaminants

    International Nuclear Information System (INIS)

    This paper discusses a high-throughput liquid-absorption preconcentrator (HTLAP) developed for rapid and/or ultrasensitive detection and analysis of trace air contaminants. The HTLAP consists of an internally wetted (6 cm I.D., 30 cm long) glass tube through which the sampled air is drawn in a swirling, highly turbulent motion that facilitates material transfer to a liquid film covering and draining down the inner wall of the tube. The liquid is collected at a rate of 0.1-2 (usually 0.1) mL/min. For validation, carrier gas (nitrogen) from a vapor generator, containing known analyte concentrations and flowing at an adjustable rate of 0.05-0.5 L/min, was mixed at the preconcentrator inlet with ambient air drawn at a rate of 600-800 L/min. The HTLAP's collection efficiency was measured by comparing the amount of analyte collected in the liquid with the amounts collected by sorbent tubes over comparable periods of time before and after each experimental run. For cocaine and heroin vapor concentrations of 0.1-150 parts per trillion by volume, the collection efficiency was 55 ± 30%, as measured by liquid chromatography with electrochemical detection. The HTLAP should reduce the detection limit and/or the sampling time for trace air contaminants by several orders or magnitude

  1. Characterization and remediation of a mixed waste-contaminated site at Kirtland Air Force Base, New Mexico

    International Nuclear Information System (INIS)

    In the area of environmental restoration, one of the most challenging problems is the task of remediating mixed waste-contaminated sites. This paper discusses a successful Interim Corrective Measure (ICM) performed at a mixed waste-contaminated site on Kirtland Air Force Base (AFB) in Albuquerque, New Mexico. The site, known as RW-68, Cratering Area and Radium Dump/Slag Piles, was used during the late 1940s and early 1950s for the destruction and incineration of captured World War II aircraft. It contained 19 slag piles totaling approximately 150 tons of slag, ash, refractory brick, and metal debris. The piles were contaminated with radium-226 and RCRA-characteristic levels of heavy metals. Therefore, the piles were considered mixed waste. To eliminate the threat to human health and the environment, an ICM of removal, segregation, stabilization, and disposal was conducted from October through December 1996. Approximately 120 cubic yards (cu yds) of mixed waste, 188 cu yds of low-level radioactive-contaminated soil, 1 cu yd of low-level radioactive-contaminated debris, 5 cu yds of RCRA-characteristic hazardous waste, and 45 tons of nonhazardous debris were stabilized and disposed of during the ICM. To render the RCRA metals and radionuclides insoluble, stabilization was performed on the mixed and RCRA-characteristic waste streams. All stabilized material was subjected to TCLP analysis to verify it no longer exhibited RCRA-characteristic properties. Radiological and geophysical surveys were conducted concurrently with site remediation activities. These surveys provided real-time documentation of site conditions during each phase of the ICM and confirmed successful cleanup of the site. The three radioactive waste streams, stabilized mixed waste, low-level radioactive-contaminated soil, and low-level radioactive-contaminated debris, were disposed of at the Envirocare low-level radioactive disposal facility

  2. The Contaminant Distribution in a Ventilated Room with Different Air Terminal Devices

    DEFF Research Database (Denmark)

    Heiselberg, Per; Nielsen, Peter V.

    of the jets and the comfort requirements applied to measured air velocities in the occupied zone. Normalized concentration distribution in the test room is determined along a vertical line through the middle of the room as a function of the air exchange rate and the density of the tracer gas. The...... relative ventilation efficiency, , based on the room average concentration is also determined as a function of the air exchange rate and the density of the tracer gas. The influence from the position of the return opening on the relative ventilation efficiency is found for one air terminal device.......The room ventilation is investigated for three different air terminal devices under isothermal conditions. Velocity distribution in the occupied zone is measured for each air terminal device at different air exchange rates. The maximum air exchange rate is determined on the base of both the throw...

  3. Nitric Oxide and Oxygen Air-Contamination Effects on Extinction Limits of Non-Premixed Hydrocarbon-Air Flames for a HIFiRE Scramjet

    Science.gov (United States)

    Pellett, Gerald L.; Dawson, Lucy C.; Vaden, Sarah N.; Wilson, Lloyd G.

    2009-01-01

    Unique nitric oxide (NO) and oxygen air-contamination effects on the extinction Flame Strength (FS) of non-premixed hydrocarbon (HC) vs. air flames are characterized for 7 gaseous HCs, using a new idealized 9.3 mm straight-tube Opposed Jet Burner (OJB) at 1 atm. FS represents a laminar strain-induced extinction limit based on cross-section-average air jet velocity, Uair, that sustains combustion of a counter jet of gaseous fuel just before extinction. Besides ethane, propane, butane, and propylene, the HCs include ethylene, methane, and a 64 mole-% ethylene / 36 % methane mixture, the writer s previously recommended gaseous surrogate fuel for HIFiRE scramjet tests. The HC vs. clean air part of the work is an extension of a May 2008 JANNAF paper that characterized surrogates for the HIFiRE project that should mimic the flameholding of reformed (thermally- or catalytically-cracked) endothermic JP-like fuels. The new FS data for 7 HCs vs. clean air are thus consolidated with the previously validated data, normalized to absolute (local) axial-input strain rates, and co-plotted on a dual kinetically dominated reactivity scale. Excellent agreement with the prior data is obtained for all 7 fuels. Detailed comparisons are also made with recently published (Univ. Va) numerical results for ethylene extinction. A 2009-revised ethylene kinetic model (Univ. Southern Cal) led to predicted limits within approx. 5 % (compared to 45 %, earlier) of this writer s 2008 (and present) ethylene FSs, and also with recent independent data (Univ. Va) obtained on a new OJB system. These +/- 5 % agreements, and a hoped-for "near-identically-performing" reduced kinetics model, would greatly enhance the capability for accurate numerical simulations of surrogate HC flameholding in scramjets. The measured air-contamination effects on normalized FS extinction limits are projected to assess ongoing Arc-Heater-induced "facility test effects" of NO production (e.g., 3 mole-%) and resultant oxygen

  4. Air sampling procedures to evaluate microbial contamination: a comparison between active and passive methods in operating theatres

    Directory of Open Access Journals (Sweden)

    Napoli Christian

    2012-08-01

    Full Text Available Abstract Background Since air can play a central role as a reservoir for microorganisms, in controlled environments such as operating theatres regular microbial monitoring is useful to measure air quality and identify critical situations. The aim of this study is to assess microbial contamination levels in operating theatres using both an active and a passive sampling method and then to assess if there is a correlation between the results of the two different sampling methods. Methods The study was performed in 32 turbulent air flow operating theatres of a University Hospital in Southern Italy. Active sampling was carried out using the Surface Air System and passive sampling with settle plates, in accordance with ISO 14698. The Total Viable Count (TVC was evaluated at rest (in the morning before the beginning of surgical activity and in operational (during surgery. Results The mean TVC at rest was 12.4 CFU/m3 and 722.5 CFU/m2/h for active and passive samplings respectively. The mean in operational TVC was 93.8 CFU/m3 (SD = 52.69; range = 22-256 and 10496.5 CFU/m2/h (SD = 7460.5; range = 1415.5-25479.7 for active and passive samplings respectively. Statistical analysis confirmed that the two methods correlate in a comparable way with the quality of air. Conclusion It is possible to conclude that both methods can be used for general monitoring of air contamination, such as routine surveillance programs. However, the choice must be made between one or the other to obtain specific information.

  5. Modelling total suspended solids, E. coli and carbamazepine, a tracer of wastewater contamination from combined sewer overflows

    Science.gov (United States)

    Pongmala, Khemngeun; Autixier, Laurène; Madoux-Humery, Anne-Sophie; Fuamba, Musandji; Galarneau, Martine; Sauvé, Sébastien; Prévost, Michèle; Dorner, Sarah

    2015-12-01

    Urban source water protection requires knowledge of sources of fecal contamination upstream of drinking water intakes. Combined and sanitary sewer overflows (CSOs and SSOs) are primary sources of microbiological contamination and wastewater micropollutants (WWMPs) in urban water supplies. To quantify the impact of sewer overflows, predictive simulation models are required and have not been widely applied for microbial contaminants such as fecal indicator bacteria and pathogens in urban drainage networks. The objective of this study was to apply a simulation model to estimate the dynamics of three contaminants in sewer overflows - total suspended solids, Escherichia coli (E. coli) and carbamazepine, a WWMP. A mixed combined and pseudo-sanitary drainage network in Québec, Canada was studied and modelled for a total of 7 events for which water quality data were available. Model results were significantly correlated with field water quality data. The model confirmed that the contributions of E. coli from runoff and sewer deposits were minor and their dominant source was from sewage. In contrast, the main sources of total suspended solids were stormwater runoff and sewer resuspension. Given that it is not present in stormwater, carbamazepine was found to be a useful stable tracer of sewage contributions to total contaminant loads and also provided an indication of the fraction of total suspended solids originating from sewer deposits because of its similar response to increasing flowrates.

  6. Electrokinetic-Enhanced Remediation of Phenanthrene-Contaminated Soil Combined with Sphingomonas sp. GY2B and Biosurfactant.

    Science.gov (United States)

    Lin, Weijia; Guo, Chuling; Zhang, Hui; Liang, Xujun; Wei, Yanfu; Lu, Guining; Dang, Zhi

    2016-04-01

    Electrokinetic-microbial remediation (EMR) has emerged as a promising option for the removal of polycyclic aromatic hydrocarbons (PAHs) from contaminated soils. The aim of this study was to enhance degradation of phenanthrene (Phe)-contaminated soils using EMR combined with biosurfactants. The electrokinetic (EK) remediation, combined with Phe-degrading Sphingomonas sp. GY2B, and biosurfactant obtained by fermentation of Pseudomonas sp. MZ01, degraded Phe in the soil with an efficiency of up to 65.1 % at the anode, 49.9 % at the cathode after 5 days of the treatment. The presence of biosurfactants, electricity, and a neutral electrolyte stimulated the growth of the degrading bacteria as shown by a rapid increase in microbial biomass with time. The electrical conductivity and pH changed little during the course of the treatment, which benefitted the growth of microorganisms and the remediation of Phe-contaminated soil. The EMR system with the addition of biosurfactant had the highest Phe removal, demonstrating the biosurfactant may enhance the bioavailability of Phe and the interaction with the microorganism. This study suggests that the EMR combined with biosurfactants can be used to enhance in situ bioremediation of PAH-contaminated soils. PMID:26683200

  7. Influence of precooling cooling air on the performance of a gas turbine combined cycle

    International Nuclear Information System (INIS)

    Cooling of hot sections, especially the turbine nozzle and rotor blades, has a significant impact on gas turbine performance. In this study, the influence of precooling of the cooling air on the performance of gas turbines and their combined cycle plants was investigated. A state of the art F class gas turbine was selected, and its design performance was deliberately simulated using detailed component models including turbine blade cooling. Off design analysis was used to simulate changes in the operating conditions and performance of the gas turbines due to precooling of the cooling air. Thermodynamic and aerodynamic models were used to simulate the performance of the cooled nozzle and rotor blade. In the combined cycle plant, the heat rejected from the cooling air was recovered at the bottoming steam cycle to optimize the overall plant performance. With a 200K decrease of all cooling air stream, an almost 1.78% power upgrade due to increase in main gas flow and a 0.70 percent point efficiency decrease due to the fuel flow increase to maintain design turbine inlet temperature were predicted

  8. Experimental and theoretical study of combined solvent and steam stripping of 1,2,3,4,5,6-hexachlorocyclohexane (HCH) and mercury from contaminated natural soil

    OpenAIRE

    Brouwers, H.J.H.

    1996-01-01

    This paper reports on an experimental and theoretical study of the combined solvent and steam stripping of contaminated soil. First, feasibility experiments on the bench scale are reported concerning the stripping of soil contaminated with 1,2,3,4,5,6-hexachlorocyclohexane (HCH) and mercury. This natural soil, originating from a contaminated site, was packed and stripped in a glass column. The results of cleaning revealed removal levels to below the detection limits of the contaminants and re...

  9. Optimization of fog inlet air cooling system for combined cycle power plants using genetic algorithm

    International Nuclear Information System (INIS)

    In this research paper, a comprehensive thermodynamic modeling of a combined cycle power plant is first conducted and the effects of gas turbine inlet fogging system on the first and second law efficiencies and net power outputs of combined cycle power plants are investigated. The combined cycle power plant (CCPP) considered for this study consist of a double pressure heat recovery steam generator (HRSG) to utilize the energy of exhaust leaving the gas turbine and produce superheated steam to generate electricity in the Rankine cycle. In order to enhance understanding of this research and come up with optimum performance assessment of the plant, a complete optimization is using a genetic algorithm conducted. In order to achieve this goal, a new objective function is defined for the system optimization including social cost of air pollution for the power generation systems. The objective function is based on the first law efficiency, energy cost and the external social cost of air pollution for an operational system. It is concluded that using inlet air cooling system for the CCPP system and its optimization results in an increase in the average output power, first and second law efficiencies by 17.24%, 3.6% and 3.5%, respectively, for three warm months of year. - Highlights: • To model the combined cycle power plant equipped with fog inlet air cooling method. • To conduct both exergy and economic analyses for better understanding. • To conduct a complete optimization using a genetic algorithm to determine the optimal design parameters of the system

  10. Applicability of the Environmental Relative Moldiness Index for Quantification of Residential Mold Contamination in an Air Pollution Health Effects Study

    Directory of Open Access Journals (Sweden)

    Ali Kamal

    2014-01-01

    Full Text Available The Near-Road Exposures and Effects of Urban Air Pollutants Study (NEXUS investigated the impact of exposure to traffic-related air pollution on the respiratory health of asthmatic children in Detroit, Michigan. Since indoor mold exposure may also contribute to asthma, floor dust samples were collected in participants homes (n=112 to assess mold contamination using the Environmental Relative Moldiness Index (ERMI. The repeatability of the ERMI over time, as well as ERMI differences between rooms and dust collection methods, was evaluated for insights into the application of the ERMI metric. ERMI values for the standard settled floor dust samples had a mean ± standard deviation of 14.5±7.9, indicating high levels of mold contamination. ERMI values for samples collected from the same home 1 to 7 months apart (n=52 were consistent and without systematic bias. ERMI values for separate bedroom and living room samples were highly correlated (r=0.69, n=66. Vacuum bag dust ERMI values were lower than for floor dust but correlated (r=0.58, n=28. These results support the use of the ERMI to evaluate residential mold exposure as a confounder in air pollution health effects studies.

  11. [Environmental investigation of ground water contamination at Wright-Patterson Air Force Base, Ohio]. Volume 1, Site assessment report

    Energy Technology Data Exchange (ETDEWEB)

    1991-10-01

    In April 1990, Wright-Patterson Air Force Base (WPAFB) initiated an effort for the evaluation of potential removal of ground water contamination at the Base. This report presents a current assessment of the nature and extent of the contamination believed to be migrating across the southwestern boundary of Area C and the northern boundary of Area B based upon analysis of existing environmental data obtained from several sources. The existing data base indicates widespread, low-level contamination moving across Base boundaries at levels that pose no immediate threat to the Mad River Valley well fields. An investigation by the City of Dayton in May and June 1990, however, implies that a more identifiable plume of PCE and TCE may be crossing the southwestern boundary of Area C immediately downgradient of Landfill 5. More data is needed to delineate ground water contamination and to design and implement a suitable control system. This report concludes that although an extensive study of the boundaries in question would be the preferred approach, a limited, focused investigation and subsequent feasibility study can be accomplished with a reasonable certainty of achieving the desired outcome of this project.

  12. Evaluation of co-benefits from combined climate change and air pollution reduction strategies

    Science.gov (United States)

    Leitao, Joana; Van Dingenen, Rita; Dentener, Frank; Rao, Shilpa

    2014-05-01

    The connection of climate change and air pollution is becoming more relevant in the process of policy making and implementation of emission control strategies because of resulting co-benefits and trade-offs. Some sectors, such as fossil fuel combustion, are sources of both pollutants (NOx and PM) as well as greenhouse gas (CO2). Additionally, the use of wood burning as biofuel to reduce climate impact may in fact deteriorate air quality. Furthermore, several air pollutants are important radiative forcers and regulating their emissions impacts on climate. It is evident that both problems need to be undertaken with a common strategy and the existence of cross-policy with co-benefits may encourage their implementation. The LIMITS FP7 project (http://www.feem-project.net/limits/index.html) was designed with the main goal of assessing strategies for reduction of GHG emissions so that the 2°C target can be achieved. The work developed focus on the evaluation of the implementation of strategies analysing several aspects of different scenarios, namely: the feasibility of low carbon scenarios in terms of available technologies and infrastructure, the required financial mechanisms, and also the co-benefits regarding energy security, economic development and air pollution. For the latter, five integrated assessment models (IAMs) provided greenhouse gases and pollutant emission values for several scenarios. These were based on air pollution scenarios defined according to stringency and implementation of future global legislation. They which were also combined with 2 climate policy scenarios (no climate policy and 2.8 W/m2 target). The former are mostly focused on non-climate policies and technical control measures for emissions of air pollutants, such as PM2.5, NOx and SO2, with their emission factors harmonized between the IAMs. With the global air quality source-receptor model TM5-FASST the impact of the resulting emissions was analysed and the co-benefits of combined

  13. Micrometeorological Measurement of Fetch- and Atmospheric Stability-Dependent Air- Water Exchange of Legacy Semivolatile Organic Contaminants in Lake Superior

    Science.gov (United States)

    Perlinger, J. A.; Tobias, D. E.; Rowe, M. D.

    2008-12-01

    Coastal waters including the Laurentian Great Lakes are particularly susceptible to local, regional, and long- range transport and deposition of semivolatile organic contaminants (SOCs) as gases and/or associated with particles. Recently-marketed SOCs can be expected to undergo net deposition in surface waters, whereas legacy SOCs such as polychlorinated biphenyls (PCBs) are likely to be at equilibrium with respect to air-water exchange, or, if atmospheric concentrations decrease through, e.g., policy implementation, to undergo net gas emission. SOC air-water exchange flux is usually estimated using the two-film model. This model describes molecular diffusion through the air and water films adjacent to the air-water interface. Air-water exchange flux is estimated as the product of SOC fugacity, typically based on on-shore gaseous concentration measurements, and a transfer coefficient, the latter which is estimated from SOC properties and environmental conditions. The transfer coefficient formulation commonly applied neglects resistance to exchange in the internal boundary layer under atmospherically stable conditions, and the use of on-shore gaseous concentration neglects fetch-dependent equilibration, both of which will tend to cause overestimation of flux magnitude. Thus, for legacy chemicals or in any highly contaminated surface water, the rate at which the water is cleansed through gas emission tends to be over-predicted using this approach. Micrometeorological measurement of air-water exchange rates of legacy SOCs was carried out on ships during four transect experiments during off-shore flow in Lake Superior using novel multicapillary collection devices and thermal extraction technology to measure parts-per-quadrillion SOC levels. Employing sensible heat in the modified Bowen ratio, fluxes at three over-water stations along the transects were measured, along with up-wind, onshore gaseous concentration and aqueous concentration. The atmosphere was unstable for

  14. Combined utilization of DGTs and bioindicators to trace chemical contamination threats on coastal ecosystems

    OpenAIRE

    Richir, Jonathan; Luy, Nicolas; Serpe, Pierre; Lefèbvre, Lucie; Deraikem, Alexandre; Lepoint, Gilles; Biondo, Renzo; Gobert, Sylvie

    2011-01-01

    Trace metal monitoring in marine organisms and their living habitats permit to trace chronic or acute contaminations of marine ecosystems due to human activities. While dissolved trace metal concentrations give us an overall and punctual view over biota contamination status, bioindicator species put their bioavailable and possible toxic fraction in an obvious. However, difficulties mainly inherent to metal measurements in seawater lead field ecotoxicologists to study marine pollution essentia...

  15. 21Pb dating of sediments in a heavily contaminated drainage channel to the La Plata estuary in Buenos Aires, Argentina

    International Nuclear Information System (INIS)

    Concentrations of 21Pb and 137Cs in sediment samples collected from two cores at a drainage channel to the La Plata river estuary in Buenos Aires, Argentina, were measured using ultralow-background detection systems. The 21Pb data were used to determine the rate of sediment accumulation of the sites. These results were correlated with some heavy metal (chromium and lead) concentrations of the samples in an attempt to characterize the historical input of contaminants due to the industrial development, which has taken place in this area over the last century. The 137Cs measurements demonstrate that cesium dating is not adequate in regions of the southern hemisphere

  16. Performance of personalized ventilation in a room with an underfloor air distribution system: transport of contaminants between occupants

    DEFF Research Database (Denmark)

    Cermak, Radim; Melikov, Arsen Krikor

    2003-01-01

    Studies have documented that personalized ventilation, which provides clean air at each office workplace, is able to improve substantially the quality of air inhaled by occupants. However, the interaction between the airflow generated by personalized ventilation and the airflow pattern outside the...... workplaces has not been studied in detail. This paper presents a study on the performance of a personalized ventilation system installed in a full-scale test room with an underfloor air distribution system. Transport of human-produced airborne pollutants (in real life they can be infectious agents) between...... two occupants was examined using a tracer-gas. Two breathing thermal manikins were used to simulate occupants. The results show that the tested combination of personalized and underfloor ventilation was not able to decrease concentration of the human-produced airborne pollutants in air inhaled by the...

  17. Assessment of internal contamination problems associated with bioregenerative air/water purification systems

    Science.gov (United States)

    Johnson, Anne H.; Bounds, B. Keith; Gardner, Warren

    1990-01-01

    The emphasis is to characterize the mechanisms of bioregenerative revitalization of air and water as well as to assess the possible risks associated with such a system in a closed environment. Marsh and aquatic plants are utilized for purposes of wastewater treatment as well as possible desalinization and demineralization. Foliage plants are also being screened for their ability to remove toxic organics from ambient air. Preliminary test results indicate that treated wastewater is typically of potable quality with numbers of pathogens such as Salmonella and Shigella significantly reduced by the artificial marsh system. Microbiological analyses of ambient air indicate the presence of bacilli as well as thermophilic actinomycetes.

  18. The significance of determining air exchange rate in dwellings and buildings to calculate the inhalation dose in indoor air from outdoor air contaminated with radioactive material

    International Nuclear Information System (INIS)

    Following the first part, in this paper on a real case of escaped radioactive matter in gaseous or aerosol form the significance of known the air exchange rate for a prediction of wasted inhalation doses to population is illustrated. (authors)

  19. Monitoring of environmental contaminants in air and precipitation, annual report 2014

    OpenAIRE

    Nizzetto, Pernilla Bohlin; Aas, Wenche; Warner, Nicholas Alexander

    2015-01-01

    This report presents results from 2014 for persistent organic pollutants (POPs) and heavy metals from the rural air- and precipitation chemistry monitoring network in Norway. These results are compared to previous years.

  20. Environmental contaminants in fish from Mere Brook - U.S. Naval Air Station, Brunswick, Maine

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Mere Brook bisects three former landfills at the U.S. Naval Air Station in Brunswick, Maine (NASB). Leachate, soil, and sediment analyzed during Superfund remedial...

  1. Integrated optics ring-resonator chemical sensor for detection of air contamination

    Science.gov (United States)

    Manfreda, A. M.; Homer, M. L.; Ksendzov, A.

    2004-01-01

    We report a silicon nitride-based ring resonator chemical sensor with sensing polymer coating. Its sensitivity to isopropanol in air is at least 50 ppm - well under the permissible exposure level of 400 ppm.

  2. Intregrated optics ring-resonator chemical sensor for detection of air contamination

    Science.gov (United States)

    Ksendzov, Alexander; Homer, Margie L.; Manfreda, Allison M.

    2004-01-01

    We report a silicon nitride-based ring resonator chemical sensor with sensing polymer coating. Its sensitivity to isopropanol in air is at least 50 ppm - well under the permissible exposure level of 400 ppm.

  3. A Novel Pumped Hydro Combined with Compressed Air Energy Storage System

    Directory of Open Access Journals (Sweden)

    Erren Yao

    2013-03-01

    Full Text Available A novel pumped hydro combined with compressed air energy storage (PHCA system is proposed in this paper to resolve the problems of bulk energy storage in the wind power generation industry over an area in China, which is characterised by drought and water shortages. Thermodynamic analysis of the energy storage system, which focuses on the pre-set pressure, storage volume capacity, water air volume ratio, pump performance, and water turbine performance of the storage system, is also presented. This paper discovers how such parameters affect the performance of the whole system. The ideal performance of this novel system has the following advantages: a simple, highly effective and low cost structure, which is comparable to the efficiency of a traditional pumped hydro storage system. Research results show a great solution to the current storage constraints encountered in the development of the wind power industry in China, which have been widely recognised as a bottleneck in the wind energy storage industry.

  4. The effect of storage in damp air and damp argon on pond water contaminated CAGR fuel cladding steels

    International Nuclear Information System (INIS)

    Retention of the mechanical integrity of fuel element assemblies during dry storage forms part of the strategy for any dry-store and is important for the ease of eventual reprocessing or disposal. This report describes a number of corrosion experiments which have been carried out on coupons of unirradiated CAGR fuel cladding steel which have been contaminated with simulated pond water. Two potential dry-store problem areas have been addressed. First is the possibility of failure of the dry-store mild steel container, allowing damp air to replace the nominally dry argon cover gas. Second is the possibility of water-logged failed fuel being inadvertently containerised giving rise to a humid argon atmosphere within the dry-store container. Specimens of niobium stabilised and titanium nitride strengthened CAGR fuel cladding steels in virgin, pre-oxidised and laboratory sensitised states have been exposed at temperatures of 1500C and 4000C, to air saturated with water at 100C and to argon saturated at 250C. Most specimens were contaminated with simulated pond water deposits containing chloride anion concentrations up to 10 ppm. No deleterious effects were observed either gravimetrically or metallographically after exposures between 10039 hours and 13152 hours. However, the absence of stress and radiation in these experiments means that caution should be exercised in applying the results to situations in which those conditions are present. (author)

  5. Combination of multielement technique (INAA and ICP-MS) for a French air pollution bio-monitoring survey using mosses

    International Nuclear Information System (INIS)

    This work presents the use of two trace analysis techniques through the data obtained for a significant part of the 557 mosses sampled in France. Sampling were made within the framework of European survey carried out in 1995-1996 and proposed by the Nordic Council. The analyses were produced with a combination of two multielement analysis techniques: INAA (Instrumental Neutron Activation Analysis) and ICP-MS (Inductively Coupled Plasma Mass Spectrometry). Theses two techniques were suitable for trace analyses in mosses. They were clearly complementary and provided for 36 elements including the heavy metals of key interest in air pollution studies. The choice of the technique for a given element depended on the feasibility (e g. Pb is not attainable by INAA), the detection limit, the analytical variability, the preparation procedures and the concentration ranges (5-100 μg/g for Pb, 0.5-5 μg/g for As). INAA measured the total content in the sample, while ICP-MS demanded a mineralization procedure resulting in losses/contamination hazards. Thus, INAA results were preferred, although this technique was time consuming. However the ICP-MS results for Cd, Cu, Ni and Pb were retained, for different reasons: detection limits (Cd, Cu), no convenient INAA conditions (Ni), and feasibility (Pb). (authors)

  6. DFT Study On Effects of CO2 Contamination in Non-Aqueous Li-Air Batteries

    DEFF Research Database (Denmark)

    Mekonnen, Yedilfana Setarge; Mýrdal, Jón Steinar Garðarsson; Vegge, Tejs

    2013-01-01

    Density Functional Theory (DFT) studies on the effects of carbon dioxide (CO2) contamination at the cathode of rechargeable non-aqueous Li-O2 batteries, where the insulating material Lithium peroxide (Li2O2) is the main discharge product. The Li2O2 growth mechanism and overpotentials are investig......Density Functional Theory (DFT) studies on the effects of carbon dioxide (CO2) contamination at the cathode of rechargeable non-aqueous Li-O2 batteries, where the insulating material Lithium peroxide (Li2O2) is the main discharge product. The Li2O2 growth mechanism and overpotentials are...... surfaces, forming a type of Lithium coordinated carbonate species (LinCO3), which reduces the effective equilibrium potential by 0.2 V. Small amounts of CO2 can also affects the morphological growth directions of Li2O2 due to blocking of nucleation centers; why may enhance the electronic conduction and...... result in an increased battery capacity. However, CO2 contamination on the Li2O2 surface confirms an asymmetric increase in the overpotentials; particularly the charging overvoltage exhibits sustantial increase, which would reduce the efficiency of the Li-air battery....

  7. Study of single and combined mass-sensitive observables of cosmic ray induced extensive air showers

    Science.gov (United States)

    Rastegarzadeh, G.; Nemati, M.

    2016-03-01

    In this study, combinations of the global arrival time, (Δτ_{global}), pseudorapidity, and lateral density distribution (ρ_{μ}) of muons, which are three mass-sensitive observables of cosmic ray induced extensive air showers, have been used as new parameters to study the primary mass discrimination around the knee energies (100 TeV-10 PeV). This is a simulation-based study and the simulations have been performed for the KASCADE array at Karlsruhe and the Alborz-I array at Tehran to study the effect of the altitude on the quality of the primary mass discrimination. The merit factors of the single and combined three mass-sensitive observables have been calculated to compare the discrimination power of combined and single observables. We have used the CORSIKA 7.4 code to simulate the extensive air showers (EASs) sample sets. Considering all aspects of our study, it is found that the ratio of the global time to the lateral density distribution of the muons gives better results than other ratios; also in the case of single observables, the muon density gives better results compared with the other observables. Also it is shown that below 1 PeV primary energies, the ratio of the muon global time to the muon density (Δτ_{global}/ρ_{μ}) results in a better mass discrimination relative to the muon density only.

  8. Determining aerosol particles by in-air micro-IL analysis combined with micro-PIXE

    Energy Technology Data Exchange (ETDEWEB)

    Kada, Wataru, E-mail: kada.wataru@jaea.go.jp [Takasaki Advanced Radiation Research Institute, Japan Atomic Energy Agency, 1233 Watanuki-machi, Takasaki, Gunma 370-1292 (Japan); Satoh, Takahiro; Yokoyama, Akihito; Koka, Masashi; Kamiya, Tomihiro [Takasaki Advanced Radiation Research Institute, Japan Atomic Energy Agency, 1233 Watanuki-machi, Takasaki, Gunma 370-1292 (Japan)

    2013-07-01

    A new external ion microbeam ion luminescence (micro-IL) imaging system was developed on a microbeam line of a 3 MV single-ended accelerator at the TIARA facility of the Japan Atomic Energy Agency. Micro-IL was combined with an in-air micro-PIXE (particle-induced X-ray emission) system to determine the chemical composition and structures of microscopic airborne particles of several micrometers in size. The hardware and software for the combined in-air micro-IL analysis system, called ion luminescence microscopic imaging and spectroscopy (ILUMIS), were studied. Wavelength-dispersive optics, including a collimator lens, a monochromator, and a photon-counting photomultiplier, were installed on the beam line. The signal processing of the IL photon signals, which were collected as spectra and two-dimensional microscopic images, was examined. Several aerosol particles were characterized to demonstrate the ILUMIS/PIXE combined analysis. The external microbeam ILUMIS analysis method provided a variety of information on the chemical and elemental composition of the micrometer-sized aerosol targets under ambient atmospheric conditions.

  9. Analytical techniques combined with chemometrics for authentication and determination of contaminants in condiments

    NARCIS (Netherlands)

    Reinholds, Ingars; Bartkevics, Vadims; Silvis, Isabelle C.J.; Ruth, van Saskia M.; Esslinger, Susanne

    2015-01-01

    Spices and herbs play an important role as flavorings, colorants, and also as bioactive compounds used in medicine and cosmetics. The presence of common contaminants, e.g., mycotoxins, pesticide residues, heavy metals, and the adulterants, e.g., azo dyes, filth and extraneous matter have been per

  10. Dispersion modeling of selected PAHs in urban air: A new approach combining dispersion model with GIS and passive air sampling

    Czech Academy of Sciences Publication Activity Database

    Sáňka, O.; Melymuk, L.; Čupr, P.; Dvorská, Alice; Klánová, J.

    2014-01-01

    Roč. 90, oct (2014), s. 88-95. ISSN 1352-2310 Institutional support: RVO:67179843 Keywords : passive air sampling * air dispersion modeling * GIS * polycyclic aromatic hydrocarbons * emission inventories Subject RIV: DI - Air Pollution ; Quality Impact factor: 3.281, year: 2014

  11. Analyzing the possibility of constructing the air heating system for an integrated solid fuel gasification combined-cycle power plant

    Science.gov (United States)

    Mikula, V. A.; Ryzhkov, A. F.; Val'tsev, N. V.

    2015-11-01

    Combined-cycle power plants operating on solid fuel have presently been implemented only in demonstration projects. One of possible ways for improving such plants consists in making a shift to hybrid process circuits of integrated gasification combined-cycle plants with external firing of solid fuel. A high-temperature air heater serving to heat compressed air is a key element of the hybrid process circuit. The article describes application of a high-temperature recuperative metal air heater in the process circuit of an integrated gasification combined-cycle power plant (IGCC). The available experience with high-temperature air heating is considered, and possible air heater layout arrangements are analyzed along with domestically produced heat-resistant grades of steel suitable for manufacturing such air heater. An alternative (with respect to the traditional one) design is proposed, according to which solid fuel is fired in a noncooled furnace extension, followed by mixing the combustion products with recirculation gases, after which the mixture is fed to a convective air heater. The use of this design makes it possible to achieve considerably smaller capital outlays and operating costs. The data obtained from thermal and aerodynamic calculations of the high-temperature air heater with a thermal capacity of 258 MW for heating air to a temperature of up to 800°C for being used in the hybrid process circuit of a combined-cycle power plant are presented.

  12. A pilot study to determine medical laser generated air contaminant emission rates for a simulated surgical procedure.

    Science.gov (United States)

    Lippert, Julia F; Lacey, Steven E; Lopez, Ramon; Franke, John; Conroy, Lorraine; Breskey, John; Esmen, Nurtan; Liu, Li

    2014-01-01

    The U.S. Occupational Safety and Health Administration (OSHA) estimates that half a million health-care workers are exposed to laser surgical smoke each year. The purpose of this study was to establish a methodology to (1) estimate emission rates of laser-generated air contaminants (LGACs) using an emission chamber, and to (2) perform a screening study to differentiate the effects of three laser operational parameters. An emission chamber was designed, fabricated, and assessed for performance to estimate the emission rates of gases and particles associated with LGACs during a simulated surgical procedure. Two medical lasers (Holmium Yttrium Aluminum Garnet [Ho:YAG] and carbon dioxide [CO2]) were set to a range of plausible medical laser operational parameters in a simulated surgery to pyrolyze porcine skin generating plume in the emission chamber. Power, pulse repetition frequency (PRF), and beam diameter were evaluated to determine the effect of each operational parameter on emission rate using a fractional factorial design. The plume was sampled for particulate matter and seven gas phase combustion byproduct contaminants (benzene, ethylbenzene, toluene, formaldehyde, hydrogen cyanide, carbon dioxide, and carbon monoxide): the gas phase emission results are presented here. Most of the measured concentrations of gas phase contaminants were below their limit of detection (LOD), but detectable measurements enabled us to determine laser operation parameter influence on CO2 emissions. Confined to the experimental conditions of this screening study, results indicated that beam diameter was statistically significantly influential and power was marginally statistically significant to emission rates of CO2 when using the Ho:YAG laser but not with the carbon dioxide laser; PRF was not influential vis-a-vis emission rates of these gas phase contaminants. PMID:24498966

  13. Data mining of plasma peptide chromatograms for biomarkers of air contaminant exposures

    OpenAIRE

    Vincent Renaud; Kumarathasan Premkumari; Karthikeyan Subramanian

    2008-01-01

    Abstract Background Interrogation of chromatographic data for biomarker discovery becomes a tedious task due to stochastic variability in retention times arising from solvent and column performance. The difficulty is further compounded when the effects of exposure (e.g. to environmental contaminants) and biological variability result in varying numbers and intensities of peaks among chromatograms. Results We developed a software tool to correct the stochastic time shifts in chromatographic da...

  14. Study on Decomposition of Indoor Air Contaminants by Pulsed Atmospheric Microplasma

    OpenAIRE

    Tomoya Kuwabara; Marius Blajan; Kazuo Shimizu

    2012-01-01

    Decomposition of formaldehyde (HCHO) by a microplasma reactor in order to improve Indoor Air Quality (IAQ) was achieved. HCHO was removed from air using one pass through reactor treatment (5 L/min). From an initial concentration of HCHO of 0.7 ppm about 96% was removed in one pass treatment using a discharge power of 0.3 W provided by a high voltage amplifier and a Marx Generator with MOSFET switches as pulsed power supplies. Moreover microplasma driven by the Marx Generator did not generate ...

  15. 液压机构液压系统的气体污染与控制%Air Contamination Control of Hydraulic System for Hydraulic Mechanism

    Institute of Scientific and Technical Information of China (English)

    邹高鹏

    2011-01-01

    针对液压机构液压系统气体污染的危害问题,介绍了高压断路器液压机构的工作原理,分析了液压系统气体污染产生的途径,重点论述了气体污染对系统运行的危害——造成渗漏油、动作时间不稳定、气蚀等现象,最后提出了防范气体污染的措施,主要从结构设计和整体布置上避免气体的存留,并采取抽真空或加装排气阀的方法进行排气处理,有效控制液压系统的气体污染.%The working principle of hydraulic mechanism for high voltage circuit breaker is introduced, and the source of air contamination in hydraulic system is analyzed. The harms of the air contamination to the circuit breaker are emphatically discussed, including oil leakage, unstable action time, and cavitation. Moreover, the methods for preventing air contamination are proposed, such as avoiding the air retention through improvement of structure design and whole layout, and exhausting the air by vacuum pump or exhaust valve, for the purpose of controlling air contamination effectively.

  16. Nonlinear Least-Squares Based Method for Identifying and Quantifying Single and Mixed Contaminants in Air with an Electronic Nose

    Directory of Open Access Journals (Sweden)

    Margaret A. Ryan

    2005-12-01

    Full Text Available The Jet Propulsion Laboratory has recently developed and built an electronic nose(ENose using a polymer-carbon composite sensing array. This ENose is designed to be usedfor air quality monitoring in an enclosed space, and is designed to detect, identify andquantify common contaminants at concentrations in the parts-per-million range. Itscapabilities were demonstrated in an experiment aboard the National Aeronautics and SpaceAdministration’s Space Shuttle Flight STS-95. This paper describes a modified nonlinearleast-squares based algorithm developed to analyze data taken by the ENose, and itsperformance for the identification and quantification of single gases and binary mixtures oftwelve target analytes in clean air. Results from laboratory-controlled events demonstrate theeffectiveness of the algorithm to identify and quantify a gas event if concentration exceedsthe ENose detection threshold. Results from the flight test demonstrate that the algorithmcorrectly identifies and quantifies all registered events (planned or unplanned, as singles ormixtures with no false positives and no inconsistencies with the logged events and theindependent analysis of air samples.

  17. Influences of ammonia contamination on leaching from air-pollution-control residues

    DEFF Research Database (Denmark)

    Guan, Zhenzhen; Chen, Dezhen; Astrup, Thomas Fruergaard

    2014-01-01

    Application of selective non-catalytic reduction systems at municipal solid waste incinerators (MSWIs) often involves over-stoichiometric injection of ammonia into flue gases. Un-reacted ammonia may be deposited on fly ash particles and can ultimately influence the leaching behaviour of air-pollution-control...

  18. A RAPID DNA EXTRACTION METHOD FOR PCR IDENTIFICATION OF FUNGAL INDOOR AIR CONTAMINANTS

    Science.gov (United States)

    Following air sampling, fungal DNA needs to be extracted and purified to a state suitable for laboratory use. Our laboratory has developed a simple method of extraction and purification of fungal DNA appropriate for enzymatic manipulation and polymerase chain reaction (PCR) appli...

  19. Influences of ammonia contamination on leaching from air-pollution-control residues

    DEFF Research Database (Denmark)

    Guan, Zhenzhen; Chen, Dezhen; Astrup, Thomas Fruergaard

    2014-01-01

    Application of selective non-catalytic reduction systems at municipal solid waste incinerators (MSWIs) often involves over-stoichiometric injection of ammonia into flue gases. Un-reacted ammonia may be deposited on fly ash particles and can ultimately influence the leaching behaviour of air-pollu...

  20. EMERGING TECHNOLOGY REPORT: DESTRUCTION OF ORGANIC CONTAMINANTS IN AIR USING ADVANCED ULTRAVIOLET FLASHLAMPS

    Science.gov (United States)

    This paper describes a new process for photo-oxidation of volatile organic compounds (VOCs) in air using an advanced ultraviolet source, a Purus xenon flashlamp. The flashlamps have greater output at 200-250 nm than medium-pressure mercury lamps at the same power and therefore ca...

  1. A Novel Constant-Pressure Pumped Hydro Combined with Compressed Air Energy Storage System

    Directory of Open Access Journals (Sweden)

    Erren Yao

    2014-12-01

    Full Text Available As intermittent renewable energy is receiving increasing attention, the combination of intermittent renewable energy with large-scale energy storage technology is considered as an important technological approach for the wider application of wind power and solar energy. Pumped hydro combined with compressed air energy storage system (PHCA is one of the energy storage systems that not only integrates the advantages but also overcomes the disadvantages of compressed air energy storage (CAES systems and pumped hydro energy storage systems to solve the problem of energy storage in China’s arid regions. Aiming at the variable working conditions of PHCA system technology, this study proposes a new constant-pressure PHCA. The most significant characteristics of this system were that the water pump and hydroturbine work under stable conditions and this improves the working efficiency of the equipment without incurring an energy loss. In addition, the constant-pressure PHCA system was subjected to energy and exergy analysis, in expectation of exploring an attractive solution for the large-scale storage of existing intermittent renewable energy.

  2. Mathematical Modeling on Combined Mid-infrared and Hot Air Drying of Beef Meat

    Directory of Open Access Journals (Sweden)

    Xiao-Lei Xie

    2015-05-01

    Full Text Available To investigate the drying models and characteristics of Combined Mid-Infrared and Hot Air (CMIHA drying BEEF MEAT (BM, a laboratory scale CMIHA dryer was applied to the treatment of BM samples in a temperature range from 40-70°C, with air velocity of 1m/s and mid-infrared of 2.8-3.1 m. Microsoft visual C sharp (C# was used to develop a Moisture Prediction System (MPS to digitize the prediction process. The results indicated that the Modified Henderson and Pabis model could present better predictions for the moisture transfer than others and the MPS could predict the moisture ratio through the whole drying process conveniently. Besides, higher temperature could accelerate effective diffusivities to increase drying rate, thus shorten the drying time. The activation energy of BM dried with CMIHA was 32.83 kJ/mol. All of these could be used in the design and operation of the combination drying beef meat.

  3. MATERIAL PARAMETER OF RUBBER GLOVE VULCANIZED USING COMBINED INFRARED AND HOT-AIR HEATING

    Directory of Open Access Journals (Sweden)

    Tipapon Khamdaeng

    2014-01-01

    Full Text Available Vulcanization is an important chemical-thermal process in production of rubber products resulting in change of material properties, increased elasticity and strength. In general, Young’s modulus is used as an indicator of elastic deformation at loading configuration. However, rubber is not truly elastic and a single parameter is insufficient to describe the whole deformation contributed by microstructure of rubber network. Therefore, we present the material parameters concerning the mechanical interaction of rubber constituents. In this study, tensile force and elongation were measured to analyze the rubber deformation. In order to describe the deformation behavior of the combined infrared and hot-air vulcanized rubber glove, the material properties, stress and stretch, were therefore presented. The stress-stretch relationships of the vulcanized rubber gloves were established based on previously well-known hyperelastic material model and their material parameters were determined using a parameter estimation technique. In conclusion, the stress-stretch relationships of the combined infrared and hot-air vulcanized rubber glove can be successfully established with our optimized material parameters; the magnitudes of rubber modulus (CR and locking stretch (λL were in a range of 0.041-0.079 MPa and 10.27-70.12, respectively. Furthermore, the resulting material parameters can be properly used to indicate the micro structural deformation.

  4. Particle re-entrainment from a powder deposit in an horizontal air flow; Mise en suspension d'une contamination particulaire par ecoulement d'air

    Energy Technology Data Exchange (ETDEWEB)

    Alloul, L.; Witschger, O. [CEA/Saclay, Inst. de Protection et de Surete Nucleaire, IPSN/DPEA/SERAC, Lab. de Physique et Metrologie des Aerosols et du Confinement, 91 - Gif-sur-Yvette (France); Renoux, A. [Paris-12 Univ., Lab. de Physique des Aerosols et de Transfert des Contaminations, 94 - Creteil (France); Le Dur, D. [Aerolab, 91 - Courtaboeuf (France); Monnatte, J. [COGEMA, Branche Combustible et Recyclage, Service Qualite Surete, 78 - Saint-Quentin-en-Yvelines (France)

    2000-07-01

    Particle re-entrainment from surfaces to turbulent air flow is an important subject in many different fields like nuclear safety, environmental air pollution, sediment transport by wind, surface contamination in semiconductor operations. Theoretical and experimental studies have been numerous and cover different aspects of the phenomena. Although a number of theoretical works have been devoted for describing the mechanisms of detachment of primary spherical particles form flat smooth surfaces in a turbulent flow, experimental data are still needed in order to comparison. Moreover, the knowledge of the effect of parameters related to the deposit (monolayer, multilayer, cone-like pile), the powder particles (particle-size distribution, adhesive properties), the surface (roughness,...),the airflow (velocity, acceleration, turbulence) or the environment (humidity,...) is still in an elementary stage. The main objective of our work is to contribute to the understanding and quantification of the parameters that govern the particle re-entrainment from a powder deposit in an turbulent horizontal airflow. Therefore, a new experimental facility called BISE (french acronym for wind tunnel for studying particle re-entrainment by airflow) has been designed and built in our laboratory. (authors)

  5. COP Prediction of an ejector refrigeration cycle combined with a vapour compression cycle for automotive air conditioning

    OpenAIRE

    Nat Suvarnakuta; Nutthanun Keerlatiyadatanapat; Thanarath Sriveerakul

    2014-01-01

    This paper presents the COP prediction of an ejector refrigeration cycle combined with a vapour compression cycle for automotive air conditioning. Using computational fluid dynamics (CFD) technique, the performance of an ejector was analyzed in term of the entrainment ratio (Rm) and critical back pressure (CBP). The results from this study were compared with a previous study of combined ejector refrigeration system for automotive air conditioning application [1] which the entrainment ratio (R...

  6. Measurement of underground contamination of non-aqueous phase liquids (NAPLs) on the basis of the radon concentration in ground level air

    International Nuclear Information System (INIS)

    It was investigated whether measurements of radon concentrations in ground level air are a suitable method of detecting sub-surface soil contamination with non-aqueous phase liquids (NAPLs). The working postulation was that, due to the very high solubility of radon in NAPLs, and the resulting accumulation of radon in NAPLs, radon exhalation to the ground level air in the proximity of such NAPL contamination should be locally reduced, thus indicating contamination of sub-surface soils with NAPLs. The research work reported was to verify the working theory by way of experiments, and to finally develop a reliable detection method for NAPL contaminations. The investigations comprised theoretical studies, laboratory experiments, experiments in defined soil columns, and extensive field studies

  7. Growth under elevated air temperature alters secondary metabolites in Robinia pseudoacacia L. seedlings in Cd- and Pb-contaminated soils.

    Science.gov (United States)

    Zhao, Y H; Jia, X; Wang, W K; Liu, T; Huang, S P; Yang, M Y

    2016-09-15

    Plant secondary metabolites play a pivotal role in growth regulation, antioxidant activity, pigment development, and other processes. As the global climate changes, increasing atmospheric temperatures and contamination of soil by heavy metals co-occur in natural ecosystems, which alters the pH of rhizosphere soil and influences the bioavailability and mobility of metals. Elevated temperatures in combination with heavy metals are expected to affect plant secondary metabolites, but this issue has not been extensively examined. Here, we investigated secondary metabolites in Robiniapseudoacacia seedlings exposed to elevated temperatures using a passive warming device in combination with Cd- and Pb-contaminated soils. Heavy metals significantly stimulated the accumulation of saponins, phenolic compounds, and flavonoids in leaves and stems; alkaloid compounds increased in leaves and decreased in stems, and condensed tannins fluctuated. Elevated temperatures, alone and in combination with Cd and Pb, caused increases in secondary metabolites in the plant tissues. Phenolic compounds showed the greatest changes among the secondary metabolites and significant interactive effects of temperature and metals were observed. These results suggest that slightly elevated temperature could enhance protective and defense mechanisms of Robinia pseudoacacia seedlings exposed to heavy metals by stimulating the production of secondary metabolites. PMID:27203519

  8. Air-born contamination caused in a high-energy proton accelerator room

    International Nuclear Information System (INIS)

    Surface contamination caused during the operation of 12-GeV proton synchrotron, KEK have been studied by gamma-ray spectrometry and imaging plate technique. The surface of accelerator component was wiped with the filter paper. PSL value of imaging plate contacted on the filter paper decreased according to the half-life of 2 weeks. Therefore, it was assumed that 32P might be produced from Ar by the high-energy protons and neutrons and deposited on the accelerator components. (author)

  9. Microbial Contamination on Used Surgical Masks among Hospital Personnel and Microbial Air Quality in their Working Wards: A Hospital in Bangkok

    Directory of Open Access Journals (Sweden)

    Pipat Luksamijarulkul

    2014-09-01

    Full Text Available Objective: To assess the relationship of bacterial and fungal contamination on used surgical masks worn by the hospital personnel and microbial air quality in their working wards. Methods: This is a cross-sectional study of 230 used surgical masks collected from 214 hospital personnel, and 215 indoor air samples collected from their working wards to culture for bacterial and fungal counts. This study was carried out at the hospital in Bangkok. Group or genus of isolated bacteria and fungi were preliminarily identified by Gram’s stain and lacto-phenol cotton blue. Data were analyzed using paired t-test and Pearson’s correlation coefficient at the significant level of p<0.050. Results: Means and standard deviation of bacterial and fungal contamination on inside area of the used masks were 47 ± 56 and 15 ± 9 cfu/ml/piece, and on outside area were 166 ± 199 and 34 ± 18 cfu/ml/piece, respectively, p<0.001. The bacterial and fungal contamination on used masks from hospital personnel working in the male and female medical wards and out-patient department, as well as the bacterial and fungal counts of the indoor air sample collected from the same area were relatively higher than the other wards. The predominant isolated bacteria and fungi contaminated on inside and outside areas of the used masks and air samples were similar (Staphylococcus spp. and Aspergillus spp.; respectively. For its relationship, results found that bacterial and fungal counts in air samples showed significantly positive correlation with the bacterial contamination load on outside area of the used masks, r=0.16, p=0.018 and r=0.21, p=0.003, respectively. Conclusion: High bacterial contamination on outside area of the used masks was demonstrated, and it showed a significant correlation with microbial air quality of working wards.

  10. COMPARATIVE CHARACTERISTICS OF STABILITY OF VARIOUS TYPES OF SOUTHERN RUSSIA’S SOILS TO COMBINE CONTAMINATION

    OpenAIRE

    Mazanko M. S.; Kolesnikov S. I.; Denisova T. V.

    2013-01-01

    The main contribution to the soil biological properties change in the combined pollution with lead and an alternating magnetic field makes lead pollution. Contribution of the interaction of factors of 20-30%. The contribution of the alternating field was insignificant or unreliable. Black soil and brown forest soils are similar in degree of resistance to the combined pollution. Grey sands have less stability

  11. Indoor air quality and health does fungal contamination play a significant role?

    Science.gov (United States)

    Bardana, Emil J

    2003-05-01

    Fungal contamination in buildings can vary greatly, and their presence in a dwelling does not necessarily constitute exposure. Measurement of mold spores and fragments varies depending on the methodology and instruments used. Meaningful comparison of data is rarely possible. The presence of a specific immune response to a fungal antigen only connotes that exposure to one or more related species has occurred, but not that there is a symptomatic clinical state. The response of individuals to indoor bioaerosols is complex and depends on age, gender, state of health, genetic makeup, and degree and time of bioaerosol exposure. In general, mold contamination in buildings is associated with incursion of water or moisture, which should be remedied as efficiently as possible. When disease occurs, it more likely is related to transient annoyance or irritational reactions. Allergic symptoms may be related to mold proliferation in the home environment. Because molds are encountered both indoors and outdoors, it is difficult to determine where the sensitivity initially arose and if the response is solely provoked by either an indoor or outdoor source. As an indoor allergen, mold is considered to be an infrequent participant in the induction of allergic disease when compared with housedust mites, animal dander, and cockroach allergens. Infection in healthy individuals is rare and usually is caused by an outdoor source. Building-related disease caused by mycotoxicosis has not been proved in the medical literature. PMID:12803364

  12. Is Distant Pollution Contaminating Local Air? Analyzing the Origins of Atmospheric Aerosols

    Directory of Open Access Journals (Sweden)

    David Geng

    2012-01-01

    Full Text Available Understanding the origin of aerosols in the atmosphere is important because of visual pollution, climate impacts, and deleterious health effects due to the inhalation of fine particles. This research analyzed aerosols characterized by their chloride, sulfate, and nitrate content as a function of size over a 3-month period. Due to wind patterns over coal-burning power plants, a higher concentration of local sulfate pollution was expected. Aerosols were harvested on the Purdue University campus using a high-volume air sampler with glass fiber filters and a five-stage impactor that separates the aerosols into five sizes. The filters were extracted in water to dissolve anions and the solution was analyzed using high-pressure liquid ion chromatography. Only trace amounts of chloride with no distinct patterns in size were detected. In total, nitrate content ranged from 0.12 to 2.10 μg/m3 and sulfate content ranged from 0.44 to 6.45 μg/m3 over a 3-month period. As for fine particles, a higher concentration of sulfate was observed. The Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT model determines air mass origin, and in this study, higher total sulfate content was observed when the air mass moved out of the southwest, and higher total nitrate content was observed when the air mass originated from the southeast. The author concluded that small particles resulted in sulfate from sulfur dioxide, typically from gas to particle conversion. High sulfur dioxide levels are directly correlated with coal-burning power plant density. Small particulate sulfate found in West Lafayette, Indiana, was determined to originate primarily from power plants in southwest Indiana. Though the results do show a significant amount of potentially harmful aerosols in West Lafayette, there is still further research to be done concerning isotopic composition of those particles in attempts to better explain the chemical pathways.

  13. Bilirubin oxidase based enzymatic air-breathing cathode: Operation under pristine and contaminated conditions

    OpenAIRE

    Santoro, Carlo; Babanova, Sofia; Erable, Benjamin; Schuler, Andrew; Atanassov, Plamen

    2016-01-01

    The performance of bilirubin oxidase (BOx) based air breathing cathode was constantly monitored over 45 days. The effect of electrolyte composition on the cathode oxygen reduction reaction (ORR) output was investigated. Particularly, deactivation of the electrocatalytic activity of the enzyme in phosphate buffer saline (PBS) solution and in activated sludge (AS) was evaluated. The greatest drop in current density was observed during the first 3 days of constant operation with a decrease of ~6...

  14. Development of In Vitro Methods for Toxicity Testing of Workplace Air Contaminants

    OpenAIRE

    Chris Winder; Amanda Hayes; Shahnaz Bakand

    2009-01-01

    While the OECD test guidelines and mostly animal assays have been used to study the toxic effects of chemicals for many years, very little is known about the potential toxicity of vast majority of inhaled chemicals. Considering large number of chemicals and complex mixtures present in indoor and outdoor air, heavy reliance on animal test methods appear to be not adequate. Continuing scientific developments are needed to improve the process of safety evaluation for the vast number of chemicals...

  15. Remediation of metal/organic contaminated soils by combined acid extraction and surfactant washing

    Energy Technology Data Exchange (ETDEWEB)

    Van Benschoten, J.E.; Ryan, M.E.; Huang, C.; Healy, T.C.; Brandl, P.J. [State Univ. of New York, Buffalo, NY (United States)

    1995-12-31

    The specific objectives of this research are to: (1) determine the solubilization of two polycyclic aromatic compounds (PAHs) (naphthalene and pyrene) using several surfactants at low pH conditions; (2) determine the losses of candidate surfactants due to precipitation or adsorption to a test soil as a function of pH; and (3) evaluate the performance of surfactants under acidic conditions for removal of lead and PAH compounds from a contaminated soil. In this paper, experimental results related to the first two objectives are presented.

  16. Organophosphates in aircraft cabin and cockpit air--method development and measurements of contaminants.

    Science.gov (United States)

    Solbu, Kasper; Daae, Hanne Line; Olsen, Raymond; Thorud, Syvert; Ellingsen, Dag Gunnar; Lindgren, Torsten; Bakke, Berit; Lundanes, Elsa; Molander, Paal

    2011-05-01

    Methods for measurements and the potential for occupational exposure to organophosphates (OPs) originating from turbine and hydraulic oils among flying personnel in the aviation industry are described. Different sampling methods were applied, including active within-day methods for OPs and VOCs, newly developed passive long-term sample methods (deposition of OPs to wipe surface areas and to activated charcoal cloths), and measurements of OPs in high-efficiency particulate air (HEPA) recirculation filters (n = 6). In total, 95 and 72 within-day OP and VOC samples, respectively, have been collected during 47 flights in six different models of turbine jet engine, propeller and helicopter aircrafts (n = 40). In general, the OP air levels from the within-day samples were low. The most relevant OP in this regard originating from turbine and engine oils, tricresyl phosphate (TCP), was detected in only 4% of the samples (min-max cabin and cockpit air, was an order of magnitude higher as compared to after engine replacement (p = 0.02). PMID:21399836

  17. Radioactive Mapping Contaminant of Alpha on The Air in Space of Repair of Hot Cell and Medium Radioactivity Laboratory in Radio metallurgy Installation

    International Nuclear Information System (INIS)

    Hot cell and space of acid laboratory medium activity in Radio metallurgy Installation are used for the examination preparation of fuel nuclear post irradiation. The sample examined is dangerous radioactive material representing which can disseminate passing air stream. The dangerous material spreading can be pursued by arranging air stream from laboratory space to examination space. To know the performance the air stream arrangement is hence conducted by radioactive mapping contaminant of alpha in laboratory / space of activity place, for example, medium activity laboratory and repair space. This mapping radioactivity contaminant is executed with the measurement level of the radioactivity from sample air taken at various height with the distance of 1 m, various distance and from potential source as contaminant spreading access. The mapping result indicate that a little spreading of radioactive material happened from acid cupboard locker to laboratory activity up to distance of 3 m from acid cupboard locker and spreading of radioactive contaminant from goods access door of the hot cell 104 to repair space reach the distance of 2 m from goods door access. Level of the radioactive contamination in the space was far under maximum limitation allowed (20 Bq / m3). (author)

  18. Influence of combined dust reducing carpet and compact air filtration unit on the indoor air quality of a classroom

    NARCIS (Netherlands)

    Scheepers, P.T.J.; Hartog, J.J. de; Reijnaerts, J.; Beckmann, G.; Anzion, R.B.M.; Poels, K.; Godderis, L.

    2015-01-01

    Primary schools mostly rely on natural ventilation but also have an interest in affordable technology to improve indoor air quality (IAQ). Laboratory tests show promising results for dust reducing carpets and compact air filtration systems but there is no information available on the performance of

  19. Chlorinated contaminants in chorio-allantoic membranes from great blue heron eggs at Whidbey Island Naval Air Station.

    Science.gov (United States)

    Cobb, G P; Norman, D M; Miller, M W; Brewer, L W; Johnston, R K

    1995-01-01

    Chorio-allantoic membranes (CAMs) were collected and analyzed for chlorinated hydrocarbons as part of a wildlife toxicology demonstration project at Naval Air Station (NAS) Whidbey Island, Washington, USA. Concentrations of DDT, DDE, DDD, Aroclor 1254, and Aroclor 1260 were found at concentrations below 0.4 ppm for 13 of 14 samples. The low correlations among DDT and its metabolites in CAMs suggest herons are not being exposed to a consistent source of these compounds. Comparison of chlorinated hydrocarbon data for CAMs from three Puget Sound heron colonies, NAS Whidbey, Samish Island and Dumas Bay, indicates contaminant burdens in herons from NAS Whidbey and Samish Island are significantly lower than burdens in herons from Dumas Bay. PMID:7874465

  20. Integration of processes induced air flotation and photo-Fenton for treatment of residual waters contaminated with xylene

    International Nuclear Information System (INIS)

    Highlights: ► We have studied the treatment of wastewater contaminated with hydrocarbons represented by the xylene, using these processes in an integrated mode: induced air flotation and photo-Fenton. ► We have selected xylene as representative contaminant due to properties of toxicity, solubility in water and vapor pressure. ► The manuscript presents a series of accurate experimental data that can be useful for material and energy optimization purposes in the xylene removal aiming the treatment of oil field produced water. - Abstract: Produced water in oil fields is one of the main sources of wastewater generated in the industry. It contains several organic compounds, such as benzene, toluene, ethyl benzene and xylene (BTEX), whose disposal is regulated by law. The aim of this study is to investigate a treatment of produced water integrating two processes, i.e., induced air flotation (IAF) and photo-Fenton. The experiments were conducted in a column flotation and annular lamp reactor for flotation and photodegradation steps, respectively. The first order kinetic constant of IAF for the wastewater studied was determined to be 0.1765 min−1 for the surfactant EO 7. Degradation efficiencies of organic loading were assessed using factorial planning. Statistical data analysis shows that H2O2 concentration is a determining factor in process efficiency. Degradations above 90% were reached in all cases after 90 min of reaction, attaining 100% mineralization in the optimized concentrations of Fenton reagents. Process integration was adequate with 100% organic load removal in 20 min. The results of the integration of the IAF with the photo-Fenton allowed to meet the effluent limits established by Brazilian legislation for disposal.

  1. Investigation of the fate of O2 contaminant in combined CO2 flooding sequestration process

    International Nuclear Information System (INIS)

    The fate of oxygen contaminant in a carbon dioxide (CO2) miscible flood/sequestration project was examined along with the economic implications of CO2 capture from stack gases which is subsequently injected as a miscible agent into a light oil reservoir. The presence of oxygen in injected carbon dioxide streams promotes corrosion and can cause degradation of the oil through low temperature oxidation reactions. The maximum levels of oxygen that can be tolerated in CO2 during miscible flooding was also examined by measuring the effects of different levels of oxygen concentration on the rate of oxygen consumption from the gas phase. Measurements were taken of the changes in oil composition and emulsion forming characteristics of the partially oxidized oil. The effect of reservoir material, temperature and reaction time were also examined and a low-temperature oxidation kinetic model was applied to determine the composition of pseudo-components. The study offers new information about the fate of oxygen contaminant and provides guidelines for residual oxygen as an impurity in the carbon dioxide feed to a CO2 miscible/sequestration project

  2. Combining phytoextraction and biochar addition improves soil biochemical properties in a soil contaminated with Cd.

    Science.gov (United States)

    Lu, Huanping; Li, Zhian; Fu, Shenglei; Méndez, Ana; Gascó, Gabriel; Paz-Ferreiro, Jorge

    2015-01-01

    The main goal of phytoremediation is to improve ecosystem functioning. Soil biochemical properties are considered as effective indicators of soil quality and are sensitive to various environmental stresses, including heavy metal contamination. The biochemical response in a soil contaminated with cadmium was tested after several treatments aimed to reduce heavy metal availability including liming, biochar addition and phytoextraction using Amaranthus tricolor L. Two biochars were added to the soil: eucalyptus pyrolysed at 600 °C (EB) and poultry litter at 400 °C (PLB). Two liming treatments were chosen with the aim of bringing soil pH to the same values as in the treatments EB and PLB. The properties studied included soil microbial biomass C, soil respiration and the activities of invertase, β-glucosidase, β-glucosaminidase, urease and phosphomonoesterase. Both phytoremediation and biochar addition improved soil biochemical properties, although results were enzyme specific. For biochar addition these changes were partly, but not exclusively, mediated by alterations in soil pH. A careful choice of biochar must be undertaken to optimize the remediation process from the point of view of metal phytoextraction and soil biological activity. PMID:25010741

  3. Volume reduction of radiocesium-contaminated soil by air-lift washing process. Demonstration studies in Iitate and Kawauchi village

    International Nuclear Information System (INIS)

    A small system was developed for volume reduction of radiocesium-contaminated soils. Included in this system was a 100-L air-lift washing chamber, a coagulation tank, and a dewatering apparatus. Soil samples (137Cs 6.2 x 103 - 1.9 x 104 Bq/kg) collected from a parking area in Iitate village, Fukushima Prefecture were put through this soil washing chamber. Results showed that 14-17% (dry weight) of the soil particles were ideally recovered with 75-86% of 137Cs (3.0 x 104 - 7.4 x 104 Bq/kg). Soil samples collected from an area with bamboo bushes, showed that 53-55% of the soil particle's weight were recovered with 87-89% of 137Cs (3.0 x 104 - 7.4 x 104 Bq/kg). Soil samples collected from a farm load and ditch in Kawauchi village (1.0 x 103 - 7.3 x 103 Bq/kg) were treated by soil washing, coagulation, and dewatering in series. Results showed that 10-14% weight of the soil particles were recovered as dewatered cake (4.4 x 103 - 3.1 x 104 Bq/kg) with only 43-46% of 137Cs. These results confirm soil-characteristic-dependency from the volume reduction efficiency of radiocesium-contaminated soils. (author)

  4. Technical rationale and sampling procedures for assessing the effects of subsurface volatile organic contaminants on indoor air quality

    Energy Technology Data Exchange (ETDEWEB)

    Wong, T.T.; Agar, J.G. [O' Connor Associates Environmental Inc., Calgary, AB (Canada); Gregoire, M.Y. [O' Connor Associates Environmental Inc., Winnipeg, MB (Canada)

    2003-07-01

    Volatile organic compounds (VOC) can affect indoor air quality through vapours released indoors by cigarette smoke, building materials, and common household solvents and cleaners. Therefore, the level of VOC contaminants might be a reliable indicator of the impact due to subsurface contamination. The following method of indirect assessment has been accepted by Canadian and American environmental regulatory bodies. This accepted method involves soil gas sampling close to the basement or ground floor slab of a building and VOC vapour transport modeling in order to estimate soil gas flow rates and VOC flux into a building. VOC flux concentration can be used to evaluate the potential human exposure to soil or groundwater derived VOCs, and to estimate the associated human health risks. This paper describes the shallow vapour sampler and sampling procedure specifically designed for collecting representative soil gas samples in the zone adjacent to a building basement or a ground floor slab, which was developed by O'Connor Associates. The results of numerical modeling, and the technical rationale behind the design of a soil gas sampling program for different soil types were presented. Soil type, depth to groundwater, and sampling well construction and their respective influence were discussed with reference to soil gas sampling programs and human health risk evaluations. 12 refs., 5 tabs., 6 figs.

  5. [Environmental investigation of ground water contamination at Wright-Patterson Air Force Base, Ohio]. Volume 5, Field Investigation report

    Energy Technology Data Exchange (ETDEWEB)

    1992-03-01

    An environmental investigation of ground water conditions has been undertaken at Wright-Patterson Air Force Base (WPAFB), Ohio to obtain data to assist in the evaluation of a potential removal action to prevent, to the extent practicable, migration of the contaminated ground water across Base boundaries. Field investigations were limited to the central section of the southwestern boundary of Area C and the Springfield Pike boundary of Area B. Further, the study was limited to a maximum depth of 150 feet below grade. Three primary activities of the field investigation were: (1) installation of 22 monitoring wells, (2) collection and analysis of ground water from 71 locations, (3) measurement of ground water elevations at 69 locations. Volatile organic compounds including trichloroethylene, perchloroethylene, and/or vinyl chloride were detected in concentrations exceeding Maximum Contaminant Levels (MCL) at three locations within the Area C investigation area. Ground water at the Springfield Pike boundary of Area B occurs in two primary units, separated by a thicker-than-expected clay layers. One well within Area B was determined to exceed the MCL for trichloroethylene.

  6. Determination of contamination in the air of reactor containment. Sampling and measuring techniques

    International Nuclear Information System (INIS)

    For the purposes of radiological safety work, the most important elements emerging from the primary circuit and responsible for contamination of the containment are noble gases due to fission or activation, iodine in different physico-chemical forms, and tritium. Sampling and measuring techniques used in studies conducted on in-service reactors (pressurized-water and fast reactor plants) are described, together with the results obtained. The method used for measuring the activity of iodine in its different forms (penetrating or non-penetrating) is to trap the iodine by means of a selective sampling device. The measurements are then made by gamma spectrometry. The technique used for measuring the noble gases is to enrich the carrier gas by means of cold traps, and then to make measurements with an ionization chamber or by gamma spectrometry. Tritium is trapped by bubbling through water and its activity measured with a liquid scintillation detector or proportional counter. (author)

  7. COMPARATIVE CHARACTERISTICS OF STABILITY OF VARIOUS TYPES OF SOUTHERN RUSSIA’S SOILS TO COMBINE CONTAMINATION

    Directory of Open Access Journals (Sweden)

    Mazanko M. S.

    2013-11-01

    Full Text Available The main contribution to the soil biological properties change in the combined pollution with lead and an alternating magnetic field makes lead pollution. Contribution of the interaction of factors of 20-30%. The contribution of the alternating field was insignificant or unreliable. Black soil and brown forest soils are similar in degree of resistance to the combined pollution. Grey sands have less stability

  8. Separation of Contaminants from Deinking Process Water by Dissolved Air Flotation: Effect of Flocculant Charge Density

    OpenAIRE

    Miranda Carreño, Rubén; Blanco Suárez, Ángeles; Fuente González, Elena de la; Negro Álvarez, Carlos Manuel

    2008-01-01

    The effect of charge density of 5 cationic polyacrylamides (C-PAMs)and 3 anionic polyacrylamides (A-PAMs) in single and in dual treatments with a coagulant on the flocculation and removal of dissolved and colloidal material by dissolved air flotation (DAF) in papermaking has been studied. In single systems, good results were achieved both with low and high charge C-PAMs(1.0and 3.0–3.5 meq/g). In dual sy tems, high charge C-PAMs (3.0–3.5 meq/g)and A-PAMs (1.5 meq/g), were the most efficient. R...

  9. Air Pollution and Preterm Birth in the U.S. State of Georgia (2002–2006): Associations with Concentrations of 11 Ambient Air Pollutants Estimated by Combining Community Multiscale Air Quality Model (CMAQ) Simulations with Stationary Monitor Measurements

    OpenAIRE

    Hao, Hua; Chang, Howard H.; Holmes, Heather A.; Mulholland, James A.; Klein, Mitch; Darrow, Lyndsey A.; Strickland, Matthew J

    2015-01-01

    Background: Previous epidemiologic studies suggest associations between preterm birth and ambient air pollution. Objective: We investigated associations between 11 ambient air pollutants, estimated by combining Community Multiscale Air Quality model (CMAQ) simulations with measurements from stationary monitors, and risk of preterm birth (< 37 weeks of gestation) in the U.S. state of Georgia. Methods: Birth records for singleton births ≥ 27 weeks of gestation with complete covariate informatio...

  10. District Heating Mode Analysis Based on an Air-cooled Combined Heat and Power Station

    Directory of Open Access Journals (Sweden)

    Pei Feng Li

    2014-03-01

    Full Text Available As an important research subject, district heating with combined heat and power (CHP has significant potential for energy conservation. This paper utilised a 200 MW air-cooled unit as an actual case and presented a design scheme and energy consumption analysis of three typical CHP modes, including the low vacuum mode (LVM, the extraction condensing mode (ECM, and the absorbing heat pump mode (AHPM. The advantages and disadvantages of each mode (including their practical problems were analysed, and suggestions for the best mode were proposed. The energy consumption of the three heating modes changed with the heating load. When the heating load was increased, the net power of the entire system decreased to different degrees. In this paper, the energy conservation effect of the LVM was the most ideal, followed by the ECM and the AHPM. Besides, the LVM and AHPM were able to supply larger heat loads than the ECM, which was limited by the minimum cooling flow of the low pressure cylinder. Furthermore, in order to get a more general conclusion, a similar case with an air-cooled 300 MW unit is studied, showing that the fuel consumption levels of ECM and AHPM have changed.

  11. Analysis and Optimization of a Compressed Air Energy Storage—Combined Cycle System

    Directory of Open Access Journals (Sweden)

    Wenyi Liu

    2014-06-01

    Full Text Available Compressed air energy storage (CAES is a commercial, utility-scale technology that provides long-duration energy storage with fast ramp rates and good part-load operation. It is a promising storage technology for balancing the large-scale penetration of renewable energies, such as wind and solar power, into electric grids. This study proposes a CAES-CC system, which is based on a conventional CAES combined with a steam turbine cycle by waste heat boiler. Simulation and thermodynamic analysis are carried out on the proposed CAES-CC system. The electricity and heating rates of the proposed CAES-CC system are lower than those of the conventional CAES by 0.127 kWh/kWh and 0.338 kWh/kWh, respectively, because the CAES-CC system recycles high-temperature turbine-exhausting air. The overall efficiency of the CAES-CC system is improved by approximately 10% compared with that of the conventional CAES. In the CAES-CC system, compressing intercooler heat can keep the steam turbine on hot standby, thus improving the flexibility of CAES-CC. This study brought about a new method for improving the efficiency of CAES and provided new thoughts for integrating CAES with other electricity-generating modes.

  12. Effect of Particulate Contaminants on the Development of Biofilms at Air/Water Interfaces.

    Science.gov (United States)

    Zhang, Zhenhuan; Christopher, Gordon

    2016-03-22

    The development of biofilms at air/water or oil/water interfaces has important ramifications on several applications, but it has received less attention than biofilm formation on solid surfaces. A key difference between the growth of biofilms on solid surfaces versus liquid interfaces is the range of complicated boundary conditions the liquid interface can create that may affect bacteria, as they adsorb onto and grow on the interface. This situation is exacerbated by the existence of complex interfaces in which interfacially adsorbed components can even more greatly affect interfacial boundary conditions. In this work, we present evidence as to how particle-laden interfaces impact biofilm growth at an air/water interface. We find that particles can enhance the rate of growth and final strength of biofilms at liquid interfaces by providing sites of increased adhesive strength for bacteria. The increased adhesion stems from creating localized areas of hydrophobicity that protrude in the water phase and provide sites where bacteria preferentially adhere. This mechanism is found to be primarily controlled by particle composition, with particle size providing a secondary effect. This increased adhesion through interfacial conditions creates biofilms with properties similar to those observed when adhesion is increased through biological means. Because of the generally understood ubiquity of increased bacteria attachment to hydrophobic surfaces, this result has general applicability to pellicle formation for many pellicle-forming bacteria. PMID:26943272

  13. Study on decomposition of indoor air contaminants by pulsed atmospheric microplasma.

    Science.gov (United States)

    Shimizu, Kazuo; Kuwabara, Tomoya; Blajan, Marius

    2012-01-01

    Decomposition of formaldehyde (HCHO) by a microplasma reactor in order to improve Indoor Air Quality (IAQ) was achieved. HCHO was removed from air using one pass through reactor treatment (5 L/min). From an initial concentration of HCHO of 0.7 ppm about 96% was removed in one pass treatment using a discharge power of 0.3 W provided by a high voltage amplifier and a Marx Generator with MOSFET switches as pulsed power supplies. Moreover microplasma driven by the Marx Generator did not generate NOx as detected by a chemiluminescence NOx analyzer. In the case of large volume treatment the removal ratio of HCHO (initial concentration: 0.5 ppm) after 60 minutes was 51% at 1.2 kV when using HV amplifier considering also a 41% natural decay ratio of HCHO. The removal ratio was 54% at 1.2 kV when a Marx Generator energized the electrodes with a 44% natural decay ratio after 60 minutes of treatment. PMID:23202173

  14. Study on Decomposition of Indoor Air Contaminants by Pulsed Atmospheric Microplasma

    Directory of Open Access Journals (Sweden)

    Tomoya Kuwabara

    2012-10-01

    Full Text Available Decomposition of formaldehyde (HCHO by a microplasma reactor in order to improve Indoor Air Quality (IAQ was achieved. HCHO was removed from air using one pass through reactor treatment (5 L/min. From an initial concentration of HCHO of 0.7 ppm about 96% was removed in one pass treatment using a discharge power of 0.3 W provided by a high voltage amplifier and a Marx Generator with MOSFET switches as pulsed power supplies. Moreover microplasma driven by the Marx Generator did not generate NOx as detected by a chemiluminescence NOx analyzer. In the case of large volume treatment the removal ratio of HCHO (initial concentration: 0.5 ppm after 60 minutes was 51% at 1.2 kV when using HV amplifier considering also a 41% natural decay ratio of HCHO. The removal ratio was 54% at 1.2 kV when a Marx Generator energized the electrodes with a 44% natural decay ratio after 60 minutes of treatment.

  15. Novel atmospheric pressure plasma device releasing atomic hydrogen: reduction of microbial-contaminants and OH radicals in the air

    International Nuclear Information System (INIS)

    A novel atmospheric pressure plasma device releasing atomic hydrogen has been developed. This device has specific properties such as (1) deactivation of airborne microbial-contaminants, (2) neutralization of indoor OH radicals and (3) being harmless to the human body. It consists of a ceramic plate as a positive ion generation electrode and a needle-shaped electrode as an electron emission electrode. Release of atomic hydrogen from the device has been investigated by the spectroscopic method. Optical emission of atomic hydrogen probably due to recombination of positive ions, H+(H2O)n, generated from the ceramic plate electrode and electrons emitted from the needle-shaped electrode have been clearly observed in the He gas (including water vapour) environment. The efficacy of the device to reduce airborne concentrations of influenza virus, bacteria, mould fungi and allergens has been evaluated. 99.6% of airborne influenza virus has been deactivated with the operation of the device compared with the control test in a 1 m3 chamber after 60 min. The neutralization of the OH radical has been investigated by spectroscopic and biological methods. A remarkable reduction of the OH radical in the air by operation of the device has been observed by laser-induced fluorescence spectroscopy. The cell protection effects of the device against OH radicals in the air have been observed. Furthermore, the side effects have been checked by animal experiments. The harmlessness of the device has been confirmed

  16. Novel atmospheric pressure plasma device releasing atomic hydrogen: reduction of microbial-contaminants and OH radicals in the air

    Science.gov (United States)

    Nojima, Hideo; Park, Rae-Eun; Kwon, Jun-Hyoun; Suh, Inseon; Jeon, Junsang; Ha, Eunju; On, Hyeon-Ki; Kim, Hye-Ryung; Choi, Kyoung Hui; Lee, Kwang-Hee; Seong, Baik-Lin; Jung, Hoon; Kang, Shin Jung; Namba, Shinichi; Takiyama, Ken

    2007-01-01

    A novel atmospheric pressure plasma device releasing atomic hydrogen has been developed. This device has specific properties such as (1) deactivation of airborne microbial-contaminants, (2) neutralization of indoor OH radicals and (3) being harmless to the human body. It consists of a ceramic plate as a positive ion generation electrode and a needle-shaped electrode as an electron emission electrode. Release of atomic hydrogen from the device has been investigated by the spectroscopic method. Optical emission of atomic hydrogen probably due to recombination of positive ions, H+(H2O)n, generated from the ceramic plate electrode and electrons emitted from the needle-shaped electrode have been clearly observed in the He gas (including water vapour) environment. The efficacy of the device to reduce airborne concentrations of influenza virus, bacteria, mould fungi and allergens has been evaluated. 99.6% of airborne influenza virus has been deactivated with the operation of the device compared with the control test in a 1 m3 chamber after 60 min. The neutralization of the OH radical has been investigated by spectroscopic and biological methods. A remarkable reduction of the OH radical in the air by operation of the device has been observed by laser-induced fluorescence spectroscopy. The cell protection effects of the device against OH radicals in the air have been observed. Furthermore, the side effects have been checked by animal experiments. The harmlessness of the device has been confirmed.

  17. Combination of gamma radiation and essential oils from medicinal plants in managing Tribolium castaneum contamination of stored products.

    Science.gov (United States)

    Ahmadi, Mehrdad; Abd-alla, Adly Mohamed M; Moharramipour, Saeid

    2013-08-01

    Effectiveness of management of insect infestation of stored products with essential oils as viable alternatives to synthetic insecticides can be enhanced with gamma radiation. We studied effects of sublethal doses of essential oils from Rosmarinus officinalis (L.) and Perovskia atriplicifolia (Benth) (safe natural insecticides) in combination with gamma radiation on mortality of adults of Tribolium castaneum (Herbst). The insects were subjected to two radiation doses and two concentrations of the essential oils in the air. This combined treatment increased the mortality, which was also 3-6 times higher than could be expected from the sum of the effects of each of the treatments. The synergistic effect was more pronounced in the case of R. officinalis (L.) than in the case of P. atriplicifolia (Benth). The experiments have shown that the known insecticidal effectiveness of the essential oils can be enhanced by preliminary irradiation. Possible approaches to implementation of the combined treatment are discussed. PMID:23632647

  18. Applications of mica track microfilters: surveillance of hot contaminated air at an industrial plant

    International Nuclear Information System (INIS)

    Mica Track Microfilters (MTM) are produced by irradiation of mica with heavy ions at the UNILAC (GSI, Darmstadt) and subsequent etching. The properties of MTM will be shortly summarized. We describe the use of MTM at an industrial plant for test purposes under industrial conditions. MTM are placed into a cascade impactor into the exit gas stream of a sinter oven. Under our conditions 97% of the α-active aerosols are collected on the first MTM. The air throughput of our system is appr. 50 to 200 l/h at a pressure difference of 200 mbar. The aerosol-loaded MTM allow, among others, α-spectroscopy and particle-size determinations in an elegant manner. Finally, we describe shortly a radon-personal-dosimeter using MTM. (author)

  19. Novel method for determining DDT in vapour and particulate phases within contaminated indoor air in a malaria area of South Africa

    Energy Technology Data Exchange (ETDEWEB)

    Naude, Yvette, E-mail: yvette.naude@up.ac.za [Department of Chemistry, University of Pretoria, Private Bag X20, Hatfield 0028, Pretoria (South Africa); Rohwer, Egmont R., E-mail: egmont.rohwer@up.ac.za [Department of Chemistry, University of Pretoria, Private Bag X20, Hatfield 0028, Pretoria (South Africa)

    2012-06-12

    Highlights: Black-Right-Pointing-Pointer We present a novel denuder for the determination of DDT in contaminated indoor air. Black-Right-Pointing-Pointer Single step concentration of vapour phase on PDMS, particulate phase on filter. Black-Right-Pointing-Pointer Solvent-free green technique, sample extraction not required. Black-Right-Pointing-Pointer Ratios of airborne p,p Prime -DDD/p,p Prime -DDT and of o,p Prime -DDT/p,p Prime -DDT are unusual. Black-Right-Pointing-Pointer Insecticidal efficacy of technical DDT may be compromised. - Abstract: The organochlorine insecticide DDT (1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane) is still used for malaria vector control in certain areas of South Africa. The strict Stockholm Convention on Persistent Organic Pollutants (POPs) allows spraying on the inside of traditional dwellings with DDT. In rural villages contaminated dust presents an additional pathway for exposure to DDT. We present a new method for the determination of DDT in indoor air where separate vapour and particulate samples are collected in a single step with a denuder configuration of a multi-channel open tubular silicone rubber (polydimethylsiloxane (PDMS)) trap combined with a micro quartz fibre filter. The multi-channel PDMS trap section of the denuder concentrates vapour phase insecticide whereas particle associated insecticide is transferred downstream where it is collected on a micro-fibre filter followed by a second multi-channel PDMS trap to capture the blow-off from the filter. The multi-channel PDMS trap and filter combination are designed to fit a commercial thermal desorber for direct introduction of samples into a GC-MS. The technique is solvent-free. Analyte extraction and sample clean-up is not required. Two fractions, vapour phase and particulate phase p,p Prime -DDT, o,p Prime -DDT; p,p Prime -DDD, o,p Prime -DDD; p,p Prime -DDE and o,p Prime -DDE in 4 L contaminated indoor air, were each quantitatively analysed by GC-MS using

  20. Software sensors design for the phenols contaminated water treatment by the combination of ozonization and biodegradation

    Energy Technology Data Exchange (ETDEWEB)

    Garcia, A.; Poznyak, T.; Guerra, P.; Garcia, E. I.; Chairez, J. I.; Poznyak, A.

    2009-07-01

    Phenol and chloro phenols are strongly recalcitrant. Wastewaters containing phenols have been treated by several methods as adsorption, chemical oxidation and biological treatment. It is worth to notice that the best results have been obtained when the combination of chemical oxidation and biological treatment instead of only one of them is employed. (Author)

  1. Analysis of an Air Conditioning Coolant Solution for Metal Contamination Using Atomic Absorption Spectroscopy: An Undergraduate Instrumental Analysis Exercise Simulating an Industrial Assignment

    Science.gov (United States)

    Baird, Michael J.

    2004-01-01

    A real-life analytical assignment is presented to students, who had to examine an air conditioning coolant solution for metal contamination using an atomic absorption spectroscopy (AAS). This hands-on access to a real problem exposed the undergraduate students to the mechanism of AAS, and promoted participation in a simulated industrial activity.

  2. [Environmental investigation of ground water contamination at Wright-Patterson Air Force Base, Ohio]. Volume 5, Appendix A, Part 1, Field Investigation report

    Energy Technology Data Exchange (ETDEWEB)

    1992-03-01

    This report presents information related to the sampling of ground water at the Wright-Patterson Air Force Base. It is part of an investigation into possible ground water contamination. Information concerns well drilling/construction; x-ray diffraction and sampling; soil boring logs; and chain-of-custody records.

  3. Adsorption of Emerging Munitions Contaminants on Cellulose Surface: A Combined Theoretical and Experimental Investigation.

    Science.gov (United States)

    Shukla, Manoj K; Poda, Aimee

    2016-06-01

    This manuscript reports results of an integrated theoretical and experimental investigation of adsorption of two emerging contaminants (DNAN and FOX-7) and legacy compound TNT on cellulose surface. Cellulose was modeled as trimeric form of the linear chain of 1 → 4 linked of β-D-glucopyranos in (4)C1 chair conformation. Geometries of modeled cellulose, munitions compounds and their complexes were optimized at the M06-2X functional level of Density Functional Theory using the 6-31G(d,p) basis set in gas phase and in water solution. The effect of water solution was modeled using the CPCM approach. Nature of potential energy surfaces was ascertained through harmonic vibrational frequency analysis. Interaction energies were corrected for basis set superposition error and the 6-311G(d,p) basis set was used. Molecular electrostatic potential mapping was performed to understand the reactivity of the investigated systems. It was predicted that adsorbates will be weakly adsorbed on the cellulose surface in water solution than in the gas phase. PMID:27084096

  4. Indoor Air Contamination from Hazardous Waste Sites: Improving the Evidence Base for Decision-Making

    Science.gov (United States)

    Johnston, Jill; MacDonald Gibson, Jacqueline

    2015-01-01

    At hazardous waste sites, volatile chemicals can migrate through groundwater and soil into buildings, a process known as vapor intrusion. Due to increasing recognition of vapor intrusion as a potential indoor air pollution source, in 2015 the U.S. Environmental Protection Agency (EPA) released a new vapor intrusion guidance document. The guidance specifies two conditions for demonstrating that remediation is needed: (1) proof of a vapor intrusion pathway; and (2) evidence that human health risks exceed established thresholds (for example, one excess cancer among 10,000 exposed people). However, the guidance lacks details on methods for demonstrating these conditions. We review current evidence suggesting that monitoring and modeling approaches commonly employed at vapor intrusion sites do not adequately characterize long-term exposure and in many cases may underestimate risks. On the basis of this evidence, we recommend specific approaches to monitoring and modeling to account for these uncertainties. We propose a value of information approach to integrate the lines of evidence at a site and determine if more information is needed before deciding whether the two conditions specified in the vapor intrusion guidance are satisfied. To facilitate data collection and decision-making, we recommend a multi-directional community engagement strategy and consideration of environment justice concerns. PMID:26633433

  5. Improvement of tritium contamination monitoring of air at work places by using centralized control

    International Nuclear Information System (INIS)

    After a detailed preliminary study of actual requirements, the monitoring of atmospheric activity in a laboratory working on tritium was centralized with the aid of an automatic processing unit, almost all the programs of which are fixed. The part accessible to the operator is limited to making the few necessary modifications to the essential parameters, by which it is possible to broaden the scope for dialogue between the system and the operator. The use of a coloured television display is of particular value. Emphasis is placed on deferred treatment of the results, which is done by computing cumulative exposures and recording all incidents, even minor ones, on magnetic discs, so that risk levels at the work places, releases into the environment or the time sequence of incidents can be studied at some later time. The results obtained after a year of operation show that an intelligently designed centralized monitoring system offers many advantages: better knowledge of the risks, possibility of investigating incidents (enabling the causes to be eliminated and the planning of emergency operations to be optimized), and limitation of releases into the environment after determination of the least safe operations. The centralized control unit's performance is such that it will be useful to improve the detection system and to make, in addition, air flow-rate measurements, so that the released activities can be computed more accurately. (author)

  6. The combined influence of two agricultural contaminants on natural communities of phytoplankton and zooplankton.

    Science.gov (United States)

    Baker, Leanne F; Mudge, Joseph F; Thompson, Dean G; Houlahan, Jeff E; Kidd, Karen A

    2016-07-01

    Concentrations of glyphosate observed in the environment are generally lower than those found to exert toxicity on aquatic organisms in the laboratory. Toxicity is often tested in the absence of other expected co-occurring contaminants. By examining changes in the phytoplankton and zooplankton communities of shallow, partitioned wetlands over a 5 month period, we assessed the potential for direct and indirect effects of the glyphosate-based herbicide, Roundup WeatherMax(©) applied at the maximum label rate, both in isolation and in a mixture with nutrients (from fertilizers). The co-application of herbicide and nutrients resulted in an immediate but transient decline in dietary quality of phytoplankton (8.3 % decline in edible carbon content/L) and zooplankton community similarity (27 % decline in similarity and loss of three taxa), whereas these effects were not evident in wetlands treated only with the herbicide. Thus, even at a worst-case exposure, this herbicide in isolation, did not produce the acutely toxic effects on plankton communities suggested by laboratory or mesocosm studies. Indirect effects of the herbicide-nutrient mixture were evident in mid-summer, when glyphosate residues were no longer detectable in surface water. Zooplankton abundance tripled, and zooplankton taxa richness increased by an average of four taxa in the herbicide and nutrient treated wetlands. The lack of significant toxicity of Roundup WeatherMax alone, as well as the observation of delayed interactive or indirect effects of the mixture of herbicide and nutrients attest to the value of manipulative field experiments as part of a comprehensive, tiered approach to risk assessments in ecotoxicology. PMID:27112456

  7. Investigation on the contaminative influence of animal products due to the inhalation of air and the ingestion of soil of cattle in accidental consequence

    International Nuclear Information System (INIS)

    In an accidental release of radioactive materials to the environment, the contaminative influence of animal products due to the inhalation of air and the ingestion of soil of livestock, both of which are dealt with as minor contaminative pathways in most radioecological models but may not be neglected, was investigated with the improvement of the Korean dynamic food chain model DYNACON. Although mathematical models for both contaminative pathways have been established for considering all animal products and incorporated into the model, investigation was limited to milk. As a result, it was found that both pathways are influential in the contamination of milk in the case of an accidental release during the non-grazing period of dairy cows, i.e., the non-growing season of pasture. In the case of an accidental release during the non-grazing period, the inhalation of air was more influential than the ingestion of soil in the early days following an accidental release. While, it was the opposite with the lapse of time. If precipitation is encountered during an accidental release, contaminative influence due to the ingestion of soil was greater compared with the cases of no precipitation, in general, because of a greater deposition of radionuclides onto the ground. In the case of an accidental release during the grazing period of dairy cows, i.e., the growing season of pasture, radioactive contamination due to the ingestion of pasture was dominant irrespective of the existence of precipitation during an accidental release, consequently the contaminative influence due to the inhalation of air and the ingestion of soil was negligible

  8. Combination of gamma radiation and essential oils from medicinal plants in managing Tribolium castaneum contamination of stored products

    International Nuclear Information System (INIS)

    Effectiveness of management of insect infestation of stored products with essential oils as viable alternatives to synthetic insecticides can be enhanced with gamma radiation. We studied effects of sublethal doses of essential oils from Rosmarinus officinalis (L.) and Perovskia atriplicifolia (Benth) (safe natural insecticides) in combination with gamma radiation on mortality of adults of Tribolium castaneum (Herbst). The insects were subjected to two radiation doses and two concentrations of the essential oils in the air. This combined treatment increased the mortality, which was also 3–6 times higher than could be expected from the sum of the effects of each of the treatments. The synergistic effect was more pronounced in the case of R. officinalis (L.) than in the case of P. atriplicifolia (Benth). The experiments have shown that the known insecticidal effectiveness of the essential oils can be enhanced by preliminary irradiation. Possible approaches to implementation of the combined treatment are discussed. - Highlights: • The mortality of T. castaneum increased with an increase of the radiation dose. • R. officinalis was more toxic to T. castaneum than P. atriplicifolia. • Gamma radiation and essential oils could be used as combined methods in IPM. • Combination of radiation with essential oils made a synergistic effect. • The synergistic effect of the R–G was much more appropriate from P–G

  9. In situ stabilization/solidification pilot testing of coal tar contaminated sediment focusing on air quality testing program, Sydney, Nova Scotia

    Energy Technology Data Exchange (ETDEWEB)

    Raphael, A. [AECOM, Calgary, AB (Canada); Hilchey, J. [AECOM, Sydney, NS (Canada)

    2010-07-01

    This paper presented the results of a pilot-scale demonstration project conducted to test air quality contaminant emissions at a remediation project in Sydney, Nova Scotia. In situ sediment solidification/stabilization (S/S) was selected as a remedial solutions for sediments in an estuarine pond contaminated with polycyclic aromatic hydrocarbons (PAHs). The aim of the air monitoring program was to determine the emission rates of sediment contaminants that became airborne during remediation activities and to monitor the off-site environmental impacts of the emissions. The pilot project included driving interlocking steel sheet pile (SSP) through the sediment into the underlying natural soils, removing overlying water, homogenizing the sediment, and mixing S/S reagents into the sediment over a period of 4 days at 2 different sites. Air sampling equipment was used to monitor volumetric flow rates, benzene, naphthalene and particulate matter concentrations. Continuous real-time monitoring was used at downwind fence line perimeters and by time-weighted ambient air sampling at 6 community stations near the sites. Results of the study showed that the site-specific benzene and naphthalene emission rates were significantly lower than emission rates calculated using theoretical models. No exceedances of established community air quality limits were observed. 8 refs., 3 tabs., 3 figs.

  10. Characterisation of occupational exposure to air contaminants in a nitrate fertiliser production plant.

    Science.gov (United States)

    Hovland, Kristin H; Thomassen, Yngvar; Skaugset, Nils Petter; Skyberg, Knut; Skogstad, Marit; Bakke, Berit

    2012-08-01

    The aim of this study was to characterise personal exposures to dust, acid vapours, and gases among workers in a Norwegian nitrate fertiliser production plant, as part of an ongoing epidemiological study. In total, 178 inhalable and 179 thoracic aerosol mass fraction samples were collected from randomly chosen workers (N = 141) from three compound fertiliser departments (A, B and C), a calcium nitrate fertiliser production department, nitric acid- and ammonia-production departments, and a shipping department. The overall median inhalable and thoracic aerosol mass concentrations were generally low (1.1 mg m(-3) (min-max: production goes from raw material with phosphate rock towards the final product of fertilisers. Overall, the arithmetic mean of water-soluble Ca in the thoracic mass fraction was 51% (min-max: 1-100). A total of 169 personal samples were analysed for HNO(3) vapour and HF. The highest median concentration of HNO(3) (0.63 mg m(-3)) was in the compound fertiliser departments B, and all measurements but four of the HF concentrations were below the LOD of 190 μg m(-3). Exposures to NH(3), CO and NO(2) were measured using direct-reading electrochemical sensors and the time weighted overall averages were all below the LODs of the respective sensors, NH(3) 2 ppm; CO 2 ppm; and NO(2) 0.2 ppm, but some short-term peaks were detected. Even though our results indicate that the workers may experience peak exposure episodes when performing job tasks such as cleaning or maintenance work, the overall air concentrations are well below what is considered to cause known health risks. PMID:22777595

  11. Influences of ammonia contamination on leaching from air-pollution-control residues.

    Science.gov (United States)

    Guan, Zhenzhen; Chen, Dezhen; Astrup, Thomas Fruergaard

    2014-12-01

    Application of selective non-catalytic reduction systems at municipal solid waste incinerators (MSWIs) often involves over-stoichiometric injection of ammonia into flue gases. Un-reacted ammonia may be deposited on fly ash particles and can ultimately influence the leaching behaviour of air-pollution-control (APC) residues. Batch tests were conducted to investigate the impacts of ammonia levels on leaching of a range of metals (sodium, potassium, calcium, aluminium, chromium, iron, lead, cadmium, copper, nickel and zinc), as well as chloride and dissolved organic carbon (DOC). Specific conductivity was also identified to reflect the soluble components. The results showed that with ammonia concentrations rising from a background level of 4 to 26,400 mg l(-1), the specific conductivity increased by 2-7 times as pH varied from alkaline to acidic values. DOC release was also significantly enhanced with high ammonia levels of 1400 mg l(-1) or higher at pH > 9; however at these high ammonia concentrations, the role of DOC in cadmium, copper, nickel and zinc leaching was negligible. Based on the experimental data, chloride, sodium and potassium were leached at high concentrations regardless of pH and ammonia concentrations. For aluminium, chromium, iron and lead, ammonia had little impact on their leaching behaviour. With respect to cadmium, copper, nickel and zinc, high ammonia concentrations significantly increased leaching in the pH range of 8-12 due to the formation of metal-ammonia complexes, which was also proved in the speciation calculations. However, the overall results suggest that typical levels of ammonia injection in MSWIs are not likely to affect metal leaching from APC residues. PMID:25147306

  12. Study of high levels indoor air mercury contamination from mercury amalgam use in dentistry

    International Nuclear Information System (INIS)

    In 2005, United Nations Environment Programme (UNEP) estimated that 362 tonnes of dental mercury are consumed annually worldwide. Dental mercury amalgams also called silver fillings and amalgam fillings are widely done. These fillings gave off mercury vapours. Estimated average absorbed concentrations of mercury vapours from dental fillings vary from 3,000 to 17,000 ng Hg. Mercury (Hg) also known as quick silver is an essential constituent of dental amalgam. It is a toxic substance of global concern. A persistent pollutant, mercury is not limited to its source but it travels, on time thousands of kilometers away from the source. Scientific evidence, including, UNEP Global Mercury report, establishes mercury as an extremely toxic substance, which is a major threat to wildlife, ecosystem and human health, at a global scale. Children are more at risk from mercury poisoning which affects their neurological development and brain. Mercury poisoning diminishes memory, attention, thinking and sight. In the past, a number of studies at dental sites in many countries have been carried out and reported which have been reviewed and briefly described. This paper describes and discusses the recent investigations, regarding mercury vapours level in air, carried out at 18 dental sites in Pakistan and other countries. It is evident from the data of 42 dental sites in 17 countries, including, selected dental sites in five main cities of Pakistan, described and discussed in this paper that at most dental sites in many countries including Pakistan, the indoor mercury vapours levels exceed far above the permissible limit, recommended for safe physical and mental health. At these sites, public, in general, and the medical, paramedical staff and vulnerable population, in particular, are at most serious risk to health resulting from exposure to toxic and hazardous mercury. (author)

  13. A combination of electrokinetics and Pd/Fe PRB for the remediation of pentachlorophenol-contaminated soil

    Science.gov (United States)

    Li, Zhirong; Yuan, Songhu; Wan, Jinzhong; Long, Huayun; Tong, Man

    2011-06-01

    Electrokinetic (EK) remediation of pentachlorophenol (PCP)-contaminated soil is difficult because PCP dissociates at different pH values along soil column and shows different transport behaviors near anode and cathode. In the present study, a permeable reactive barrier (PRB) filled with reactive Pd/Fe particles was installed between anode and cathode to reach the dechlorination of PCP during its EK movement. When PRB was installed at the position of 0.3 (normalized distance from anode), PCP in the section from anode to PRB could transport through PRB, while PCP in the section from cathode to PRB was accumulated near PRB. PCP was hardly dechlorinated by PRB wherein high pH was reached. When PRB was installed at the position of 0.5 and the pH in the PRB was decreased by periodical injection of HAc, 49% of PCP was removed, and 22.9% was recovered as phenol which was mostly collected in catholyte. The mechanism of PCP removal was proposed as the EK movement of PCP into the PRB compartment, the complete dechlorination of PCP to phenol by Pd/Fe in the PRB compartment, and the subsequent removal of phenol by electroosmosis. This study proved that the combination of electrokinetics and Pd/Fe PRB was effective for the remediation of PCP-contaminated soil.

  14. Contamination and decontamination of fabrics

    International Nuclear Information System (INIS)

    An analysis is made of the problems of contamination and decontamination of clothes and underwear. Possible ways are described of contamination of fabrics (dry, wet) and in this connection the contaminant-fabric binding is underlined (in dry state, at different relative air humidity, in wet conditions in an environment of polar solvents). A survey is presented of decontamination methods and their importance. Dry methods include beatino., brushing and vacuum cleaning, wet methods include soaking and washing, dry cleaning in non-polar solvents, and the Intensol and Dual methods which combine dry cleaning and washing in one process. (B.S.)

  15. Combined effects of pharmaceuticals, personal care products, biocides and organic contaminants on the growth of Skeletonema pseudocostatum.

    Science.gov (United States)

    Petersen, Karina; Heiaas, Harald Hasle; Tollefsen, Knut Erik

    2014-05-01

    Organisms in the environment are exposed to a number of pollutants from different compound groups. In addition to the classic pollutants like the polychlorinated biphenyls, polyaromatic hydrocarbons (PAHs), alkylphenols, biocides, etc. other compound groups of concern are constantly emerging. Pharmaceuticals and personal care products (PPCPs) can be expected to co-occur with other organic contaminants like biocides, PAHs and alkylphenols in areas affected by wastewater, industrial effluents and intensive recreational activity. In this study, representatives from these four different compound groups were tested individually and in mixtures in a growth inhibition assay with the marine algae Skeletonema pseudocostatum (formerly Skeletonema costatum) to determine whether the combined effects could be predicted by models for additive effects; the concentration addition (CA) and independent action (IA) prediction model. The eleven tested compounds reduced the growth of S. pseudocostatum in the microplate test in a concentration-dependent manner. The order of toxicity of these chemicals were irgarol>fluoxetine>diuron>benzo(a)pyrene>thioguanine>triclosan>propranolol>benzophenone 3>cetrimonium bromide>4-tert-octylphenol>endosulfan. Several binary mixtures and a mixture of eight compounds from the four different compound groups were tested. All tested mixtures were additive as model deviation ratios, the deviation between experimental and predicted effect concentrations, were within a factor of 2 from one or both prediction models (e.g. CA and IA). Interestingly, a concentration dependent shift from IA to CA, potentially due to activation of similar toxicity pathways at higher concentrations, was observed for the mixture of eight compounds. The combined effects of the multi-compound mixture were clearly additive and it should therefore be expected that PPCPs, biocides, PAHs and alkylphenols will collectively contribute to the risk in areas contaminated by such complex

  16. Determination of chrysotile asbestos in air by XRD combined with separation procedure

    International Nuclear Information System (INIS)

    X-Ray diffractometric determination of chrysotile asbestos down to 0.01 mg is described. Sample preparation uses a combination of heavy liquid separation, acid treatment and flotation. Dust collected by a high-volume air sampler was detached from a membrane filter by irradiation of ultrasonic waves in acetone. Airborne dust of 20-50 mg collected in a bag-filter was directly used. To remove organic matter, the sample was suspended in a heavy liquid of ethyl iodide. Dilute hydrochloric acid was added to the sediment to remove dissoluble matter. After addition of water, sodium dodecylbenzenesulfonate (DBS) and ethanol, flotation was carried out at pH 4.8. Collected foam was centrifuged and the sediment was mounted on a non-diffracting plate for XRD analysis. The integral intensity of the chrysotile (004) diffraction line was measured to determine chrysotile concentration using a calibration graph, which was linear in the range of 0.01-0.12 mg. Recovery of chrysotile was about 90% for samples of 20-42 mg containing 0.1 mg of chrysotile in the matrix of quartz, carbon black, gypsum, cotton, rock wool, etc., and also for a bag-filter dust sample of 40 mg to which 0.1 mg chrysotile was added. (author)

  17. Sensitivity of Hollow Fiber Spacesuit Water Membrane Evaporator Systems to Potable Water Constituents, Contaminants and Air Bubbles

    Science.gov (United States)

    Bue, Grant C.; Trevino, Luis A.; Fritts, Sharon; Tsioulos, Gus

    2008-01-01

    The Spacesuit Water Membrane Evaporator (SWME) is the baseline heat rejection technology selected for development for the Constellation lunar suit. The first SWME prototype, designed, built, and tested at Johnson Space Center in 1999 used a Teflon hydrophobic porous membrane sheet shaped into an annulus to provide cooling to the coolant loop through water evaporation to the vacuum of space. This present study describes the test methodology and planning and compares the test performance of three commercially available hollow fiber materials as alternatives to the sheet membrane prototype for SWME, in particular, a porous hydrophobic polypropylene, and two variants that employ ion exchange through non-porous hydrophilic modified Nafion. Contamination tests will be performed to probe for sensitivities of the candidate SWME elements to ordinary constituents that are expected to be found in the potable water provided by the vehicle, the target feedwater source. Some of the impurities in potable water are volatile, such as the organics, while others, such as the metals and inorganic ions are nonvolatile. The non-volatile constituents will concentrate in the SWME as evaporated water from the loop is replaced by the feedwater. At some point in the SWME mission lifecycle as the concentrations of the non-volatiles increase, the solubility limits of one or more of the constituents may be reached. The resulting presence of precipitate in the coolant water may begin to plug pores and tube channels and affect the SWME performance. Sensitivity to macroparticles, lunar dust simulant, and air bubbles will also be investigated.

  18. [Environmental investigation of ground water contamination at Wright-Patterson Air Force Base, Ohio]. Volume 9, Removal action system design

    Energy Technology Data Exchange (ETDEWEB)

    1992-04-01

    This Removal Action System Design has been prepared as a Phase I Volume for the implementation of the Phase II removal action at Wright-Patterson Air Force Base (WPAFB) near Dayton, Ohio. The objective of the removal action is to prevent, to the extent practicable, the migration of ground water contaminated with chlorinated volatile organic compounds (VOCS) across the southwest boundary of Area C. The Phase 1, Volume 9 Removal Action System Design compiles the design documents prepared for the Phase II Removal Action. These documents, which are presented in Appendices to Volume 9, include: Process Design, which presents the 30 percent design for the ground water treatment system (GWTS); Design Packages 1 and 2 for Earthwork and Road Construction, and the Discharge Pipeline, respectively; no drawings are included in the appendix; Design Package 3 for installation of the Ground Water Extraction Well(s); Design Package 4 for installation of the Monitoring Well Instrumentation; and Design Package 5 for installation of the Ground Water Treatment System; this Design Package is incorporated by reference because of its size.

  19. Combined hardware-software considerations for triage of internally contaminated personnel

    International Nuclear Information System (INIS)

    Medical response to a radiological emergency involves first assessing, triaging and treating trauma, followed by determining potential hazard from radiological intake. A combined hardware-software strategy is required for this mission. The hardware strategy should consist of a dedicated detector suite capable of alpha, beta and gamma radiation detection, identification and quantification suitable for order of magnitude dose assessment. The hardware platform should provide a simple user interface suitable for field deployment. The software should provide first-on-the-scene responders with the ability to perform radiological triage in a mass casualty type event, physicians with the ability to assign treatment regimes, and long-term care medical personnel with information to provide continual risk reassessment of the patient taking into account toxicology of the decorporation therapy and dose aversion. The software should be rich in data, yet accessible through a simple user interface. Practicing in a radiological emergency exercise environment with the equipment is crucial to its efficacy in a real emergency. (authors)

  20. A combined approach to assess the microbial contamination of the archimedes palimpsest.

    Science.gov (United States)

    Piñar, Guadalupe; Sterflinger, Katja; Ettenauer, Jörg; Quandt, Abigail; Pinzari, Flavia

    2015-01-01

    A combined approach, using molecular and microscopic techniques, was used to identify the microbiota associated with the Archimedes Palimpsest, an unusual parchment manuscript. SEM analyses revealed the microbial damage to the collagen fibers and the presence of characteristic cell chains typical of filamentous bacteria and fungal spores. Molecular analysis confirmed a homogeneous bacterial community colonizing the manuscript. The phyla Proteobacteria and Actinobacteria were associated with this ancient parchment; the sequences were most related to uncultured clones detected in the human skin microbiome and in ephitelium, and to cultivated species of the genera Acinetobacter and Nocardiopsis. Nevertheless, a great variation was observed among the different sampled areas indicating fungal diversity. Blumeria spp. dominated in the healthy areas of the parchment while degraded areas showed disparate fungal communities, with dominant members of the genera Mucor and Cladosporium. In addition, the quantification of the β-actin gene by real-time PCR analyses (qPCR) revealed a higher fungal abundance on degraded areas than on the healthy ones. PMID:25135817

  1. Cobalt-Lead-Manganese oxides combined cathode catalyst for air electrode in Zinc –air battery

    International Nuclear Information System (INIS)

    Highlights: • Bi and trimetallic oxides based on Mn, Pb and Co were prepared and characterized. • Introduction of Pb and Co in MnOx catalyst promote four electron ORR. • Zinc air battery with Mn2Pb2CoOx catalyst displays much smaller charge transfer resistance in contrast to the pure MnOx. • Mn2Pb2CoOx catalyst has lower loss of performance after 500C-D cycles than the rest of the catalysts. • Zinc air battery containing Mn2Pb2CoOx has promising current and power density and also discharge capacity. - Abstract: Bi and tri metalic oxides based on Mn, Pb and Co composite catalysts were prepared by oxidation of metal acetates with KMnO4. The structure of the catalysts was characterized by X-ray diffraction (XRD). It is found that the Mn2Pb2CoOx catalyst has amorphous structure and contains various oxides of Mn, Pb and Co. Electrocatalytic activity of catalysts in 6 M KOH was studied using Cyclic Voltammetry (CV) and polarization. Cyclic Voltammetry plot of Mn2Pb2CoOx catalyst showed higher electrocatalytic activity towards the Oxygen Reduction Reaction (ORR) compared to other tri and bimetallic composite catalysts. The kinetics of ORR on the catalysts was investigated using the rotating disk electrode technique in 6 M KOH solution. From the slope of Koutecky–Levich plots, it is evident that the ORR on Mn2Pb2CoOx is a 4-electron transfer process. With these inherent features, the zinc–air battery was fabricated using various catalysts and their performance was examined for practical applications

  2. Purification of drinking water from radioactive contamination by final consumers by means of combined cation and anion exchangers

    International Nuclear Information System (INIS)

    It should be tried to develop an apparatus which makes it possible for the final consumer to purify the drinking water himself in the case of a radioactive contamination of the water. After thorough preliminary studies the most suitable kinds of exchange resins and the best arrangement for a combined cation and anion exchange resins and the best arrangement for a combined cation and anion exchange equipment were determined in inactive preliminary tests. Subsequent the useful capacity (NK) and the purifying factor (RF) were determined for the fission products 90Sr, 131I and 137Cs. The results were for 90Sr: NK = 30 1/2 x 0.5 l resin, RF >= 4.102, for 131I: NK = 32 1/2 x 0.5 l resin, RF = 3.7.102 and for 137Cs: NK > 35 1/2 x 0.5 l resin, RF >= 103. With 2 x 1 l resin the concentration of possible fission products in water can be reduced by 2 orders of magnitude ore more. A proposal for the construction of a household decontamination equipment for drinking water is made. The cost of production will be about A.S. 400,-- to 600,--. (author)

  3. Cryogenic hydrogen-induced air-liquefaction technologies for combined-cycle propulsion applications

    Science.gov (United States)

    Escher, William J. D.

    1992-01-01

    Given here is a technical assessment of the realization of cryogenic hydrogen induced air liquefaction technologies in a prospective onboard aerospace vehicle process setting. The technical findings related to the status of air liquefaction technologies are reviewed. Compact lightweight cryogenic heat exchangers, heat exchanger atmospheric constituent fouling alleviation measures, para/ortho-hydrogen shift-conversion catalysts, cryogenic air compressors and liquid air pumps, hydrogen recycling using slush hydrogen as a heat sink, liquid hydrogen/liquid air rocket-type combustion devices, and technically related engine concepts are discussed. Much of the LACE work is related to aerospaceplane propulsion concepts that were developed in the 1960's. Emphasis is placed on the Liquid Air Cycle Engine (LACE).

  4. Modeling air temperature through a combination of remote sensing and GIS data

    OpenAIRE

    Cristóbal Rosselló, Jordi; Ninyerola i Casals, Miquel; Pons, Xavier

    2008-01-01

    Air temperature is involved in many environmental processes such as actual and potential evapotranspiration, net radiation and species distribution. Ground meteorological stations provide important local data of air temperature, but a continuous surface for large and heterogeneous areas is also needed. In this paper we present a hybrid methodology between Remote Sensing and Geographical Information Systems to retrieve daily instantaneous, mean, maximum and minimum air temperatures (2002–2004)...

  5. The frequency of chromosomal aberrations in sheep from the area contaminated by depleted uranium during NATO air strikes in 1999

    Directory of Open Access Journals (Sweden)

    Fišter Svetlana L.

    2014-01-01

    Full Text Available This paper presents the results of cytogenetic studies in sheep from the region of Bujanovac that was contaminated by depleted uranium during the NATO air strikes in 1999. The study was conducted on sheep blood lymphocytes, in order to determine the frequency of chromosomal aberrations and to assess the presence of genetic risk as a result of the possible impact of depleted uranium. Blood samples for lymphocyte cultures were taken at random from the 20 animals of the households in the village of Borovac, near Bujanovac. The animals were chosen because they were pastured, fed, and watered in the NATO bombing area. With the purpose of comparing the results two control groups were cytogenetically analyzed, each consisted of 20 sheep from Zemun and Ovča, two northern localities that were not contaminated with depleted uranium. The established structural chromosomal changes were of breaks and gap types, and their frequencies in sheep of all surveyed localities were within the range of basic level values that are commonly found in the sheep lymphocyte cultures analyses. Significant differences are apparent between the values defined in the sheep from Bujanovac compared to those obtained in the sheep from the northern locality (Zemun, probably as a result of breeding of animals in the farm conditions and their being less exposed to the impact of environmental agents. There were neither elevated values of polyploid and aneuploid cells nor significant differences between the sites. According to earlier known data, depleted uranium was below the detection limit of the method applied both in the soil and feed given to cytogenetically analyzed animals. Based on the low-level changes that are in the range of the basic level changes, commonly observed in sheep lymphocytes control cultures, it cannot be said with certainty that it was depleted uranium that caused the changes, or that it is wide-spread in the region of Bujanovac. [Projekat Ministarstva nauke

  6. Combined use of a transformed red mud reactive barrier and electrokinetics for remediation of Cr/As contaminated soil.

    Science.gov (United States)

    Cappai, G; De Gioannis, G; Muntoni, A; Spiga, D; Zijlstra, J J P

    2012-01-01

    A reactive barrier (RB) of transformed red mud (TRM), a by-product of the refinement of bauxite in alumina production, was placed adjacent to the anode of an electrokinetic (EK) system with the aim of enhancing removal of chromium or arsenic, added singly to a low permeability clayey soil, and favouring entrapment. The innovative study focused on evaluation of the synergic interaction between the EK system and the RB, and of the efficiency when compared to traditional EK remediation (control tests). The results obtained underlined the successful outcome of treatment of the Cr(VI)-contaminated soil. In presence of the TRM RB, 19.4% wt. of total Cr content was detected in the anolyte and 20.6% wt. trapped in the anodic RB after 6d, versus 6.6% wt. in the anolyte and 8.8% wt. in the soil adjacent to the anode following the control run without RB. On increasing duration of treatment up to 12d, 60.8% wt. of total initial Cr was found in the anolyte and 25.5% wt. trapped in the RB, versus 9.1% wt. and 5.3% wt., respectively, after a control run of the same duration. Finally, on increasing the mass of TRM in the RB, 60.6% wt. of initial Cr content was found to have accumulated in the RB, with Cr being completely absent from the anodic chamber. Conversely, combined treatment was much less effective on As contaminated soil, at least under the operative conditions applied. Low initial As concentration and interference with iron oxides in the soil were likely the reasons underlying low efficiency while attempting As decontamination. PMID:22119416

  7. The Combination of DGT Technique and Traditional Chemical Methods for Evaluation of Cadmium Bioavailability in Contaminated Soils with Organic Amendment

    Science.gov (United States)

    Yao, Yu; Sun, Qin; Wang, Chao; Wang, Pei-Fang; Miao, Ling-Zhan; Ding, Shi-Ming

    2016-01-01

    Organic amendments have been proposed as a means of remediation for Cd-contaminated soils. However, understanding the inhibitory effects of organic materials on metal immobilization requires further research. In this study colza cake, a typical organic amendment material, was investigated in order to elucidate the ability of this material to reduce toxicity of Cd-contaminated soil. Available concentrations of Cd in soils were measured using an in situ diffusive gradients in thin films (DGT) technique in combination with traditional chemical methods, such as HOAc (aqua regia), EDTA (ethylene diamine tetraacetic acid), NaOAc (sodium acetate), CaCl2, and labile Cd in pore water. These results were applied to predict the Cd bioavailability after the addition of colza cake to Cd-contaminated soil. Two commonly grown cash crops, wheat and maize, were selected for Cd accumulation studies, and were found to be sensitive to Cd bioavailability. Results showed that the addition of colza cake may inhibit the growth of wheat and maize. Furthermore, the addition of increasing colza cake doses led to decreasing shoot and root biomass accumulation. However, increasing colza cake doses did lead to the reduction of Cd accumulation in plant tissues, as indicated by the decreasing Cd concentrations in shoots and roots. The labile concentration of Cd obtained by DGT measurements and the traditional chemical extraction methods, showed the clear decrease of Cd with the addition of increasing colza cake doses. All indicators showed significant positive correlations (p < 0.01) with the accumulation of Cd in plant tissues, however, all of the methods could not reflect plant growth status. Additionally, the capability of Cd to change from solid phase to become available in a soil solution decreased with increasing colza cake doses. This was reflected by the decreases in the ratio (R) value of CDGT to Csol. Our study suggests that the sharp decrease in R values could not only reflect the

  8. The Combination of DGT Technique and Traditional Chemical Methods for Evaluation of Cadmium Bioavailability in Contaminated Soils with Organic Amendment

    Directory of Open Access Journals (Sweden)

    Yu Yao

    2016-06-01

    Full Text Available Organic amendments have been proposed as a means of remediation for Cd-contaminated soils. However, understanding the inhibitory effects of organic materials on metal immobilization requires further research. In this study colza cake, a typical organic amendment material, was investigated in order to elucidate the ability of this material to reduce toxicity of Cd-contaminated soil. Available concentrations of Cd in soils were measured using an in situ diffusive gradients in thin films (DGT technique in combination with traditional chemical methods, such as HOAc (aqua regia, EDTA (ethylene diamine tetraacetic acid, NaOAc (sodium acetate, CaCl2, and labile Cd in pore water. These results were applied to predict the Cd bioavailability after the addition of colza cake to Cd-contaminated soil. Two commonly grown cash crops, wheat and maize, were selected for Cd accumulation studies, and were found to be sensitive to Cd bioavailability. Results showed that the addition of colza cake may inhibit the growth of wheat and maize. Furthermore, the addition of increasing colza cake doses led to decreasing shoot and root biomass accumulation. However, increasing colza cake doses did lead to the reduction of Cd accumulation in plant tissues, as indicated by the decreasing Cd concentrations in shoots and roots. The labile concentration of Cd obtained by DGT measurements and the traditional chemical extraction methods, showed the clear decrease of Cd with the addition of increasing colza cake doses. All indicators showed significant positive correlations (p < 0.01 with the accumulation of Cd in plant tissues, however, all of the methods could not reflect plant growth status. Additionally, the capability of Cd to change from solid phase to become available in a soil solution decreased with increasing colza cake doses. This was reflected by the decreases in the ratio (R value of CDGT to Csol. Our study suggests that the sharp decrease in R values could not only

  9. Combined nano-biotechnology for in-situ remediation of mixed contamination of groundwater by hexavalent chromium and chlorinated solvents.

    Science.gov (United States)

    Němeček, Jan; Pokorný, Petr; Lhotský, Ondřej; Knytl, Vladislav; Najmanová, Petra; Steinová, Jana; Černík, Miroslav; Filipová, Alena; Filip, Jan; Cajthaml, Tomáš

    2016-09-01

    The present report describes a 13month pilot remediation study that consists of a combination of Cr(VI) (4.4 to 57mg/l) geofixation and dechlorination of chlorinated ethenes (400 to 6526μg/l), achieved by the sequential use of nanoscale zerovalent iron (nZVI) particles and in situ biotic reduction supported by whey injection. The remediation process was monitored using numerous techniques, including physical-chemical analyses and molecular biology approaches which enabled both the characterization of the mechanisms involved in pollutant transformation and the description of the overall background processes of the treatment. The results revealed that nZVI was efficient toward Cr(VI) by itself and completely removed it from the groundwater (LOQ 0.05mg/l) and the subsequent application of whey resulted in a high removal of chlorinated ethenes (97 to 99%). The persistence of the reducing conditions, even after the depletion of the organic substrates, indicated a complementarity between nZVI and the whey phases in the combined technology as the subsequent application of whey phase partially assisted the microbial regeneration of the spent nZVI by promoting its reduction into Fe(II), which further supported remediation conditions at the site. Illumina sequencing and the detection of functional vcrA and bvcA genes documented a development in the reducing microbes (iron-reducing, sulfate-reducing and chlororespiring bacteria) that benefited under the conditions of the site and that was probably responsible for the high dechlorination and/or Cr(VI) reduction. The results of this study demonstrate the feasibility and high efficiency of the combined nano-biotechnological approach of nZVI and whey application in-situ for the removal of Cr(VI) and chlorinated ethenes from the groundwater of the contaminated site. PMID:26850861

  10. THERAPEUTIC OF SKIN AGING WITH CARBON DIOXIDE LASER SKIN RESURFACING AND COMBINATION WITH AIR COOLING

    Directory of Open Access Journals (Sweden)

    NKA Maya Damayanti

    2013-12-01

    Full Text Available Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 So far, a lot of people who want their face skin always looks young though age continued to grow. It cannot be denied that aging will occur in everyone although some faster or later occur. Various ways were developed by scientists to fix this issue. Laser Skin Resurfacing (LSR technique to tighten facial skin is a procedure that is popular among the public and the practice of medicine. CO2 LSR technique is still a gold standard was used. Pain during surgery can be reduced when this technique was combined with air cooling. In addition, the adverse effects of post-operative might be tolerated.   /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;}

  11. Nuclear Air-Brayton Combined Cycle Power Conversion Design, Physical Performance Estimation and Economic Assessment

    Science.gov (United States)

    Andreades, Charalampos

    The combination of an increased demand for electricity for economic development in parallel with the widespread push for adoption of renewable energy sources and the trend toward liberalized markets has placed a tremendous amount of stress on generators, system operators, and consumers. Non-guaranteed cost recovery, intermittent capacity, and highly volatile market prices are all part of new electricity grids. In order to try and remediate some of these effects, this dissertation proposes and studies the design and performance, both physical and economic, of a novel power conversion system, the Nuclear Air-Brayton Combined Cycle (NACC). The NACC is a power conversion system that takes a conventional industrial frame type gas turbine, modifies it to accept external nuclear heat at 670°C, while also maintaining its ability to co-fire with natural gas to increase temperature and power output at a very quick ramp rate. The NACC addresses the above issues by allowing the generator to gain extra revenue through the provision of ancillary services in addition to energy payments, the grid operator to have a highly flexible source of capacity to back up intermittent renewable energy sources, and the consumer to possibly see less volatile electricity prices and a reduced probability of black/brown outs. This dissertation is split into six sections that delve into specific design and economic issues related to the NACC. The first section describes the basic design and modifications necessary to create a functional externally heated gas turbine, sets a baseline design based upon the GE 7FB, and estimates its physical performance under nominal conditions. The second section explores the off-nominal performance of the NACC and characterizes its startup and shutdown sequences, along with some of its safety measures. The third section deals with the power ramp rate estimation of the NACC, a key performance parameter in a renewable-heavy grid that needs flexible capacity. The

  12. [Environmental investigation of ground water contamination at Wright- Patterson Air Force Base, Ohio]. Volume 4, Health and Safety Plan (HSP); Phase 1, Task 4 Field Investigation report: Draft

    Energy Technology Data Exchange (ETDEWEB)

    1991-10-01

    This Health and Safety Plan (HSP) was developed for the Environmental Investigation of Ground-water Contamination Investigation at Wright-Patterson Air Force Base near Dayton, Ohio, based on the projected scope of work for the Phase 1, Task 4 Field Investigation. The HSP describes hazards that may be encountered during the investigation, assesses the hazards, and indicates what type of personal protective equipment is to be used for each task performed. The HSP also addresses the medical monitoring program, decontamination procedures, air monitoring, training, site control, accident prevention, and emergency response.

  13. Steam and hot air injection for thermal rehabilitation of contaminated sites; Wasserdampf- und Heissluftinjektion zur thermischen Sanierung kontaminierter Standorte

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, R.

    2001-07-01

    Thermal in situ rehabilitation technologies are a promising alternative to conventional methods of cleaning up contaminated sites. The fact that an increase in temperature changes the physical properties of materials makes it possible, in principle, to release large quantities of pollutants within short time periods. The use of pure steam or steam/air mixtures as fluid thermal carriers permits converting subterranean non-aqueous-phase pollutants into the gas phase through increased vapour pressure and transporting them to the surface by means of soil air aspiration for further treatment. The purpose of the present two-stage research project was to systematically develop a thermal in situ rehabilitation technology using steam as fluid heat carrier and use it for land rehabilitation operations on a pilot basis. In the first, fundamental project phase aspects of heat transport (Faerber, 1997) and pollutant behaviour (Betz, 1998)in homogenous porous media upon pure steam injection were explored at a laboratory and technical scale using containers of different sizes (1D, 2D, 3D). The results were used to derive application criteria for this technology. [German] Thermische In-situ-Sanierungstechnologien stellen bei der Reinigung kontaminierter Standorte eine vielversprechende Alternative zu konventionellen Verfahren dar. Die Veraenderung physikalischer Stoffeigenschaften mit steigender Temperatur ermoeglicht grundsaetzlich hohe Schadstoffaustraege innerhalb kurzer Zeitraeume. Beim Einsatz von reinem Wasserdampf oder Wasserdampf-Luft-Gemischen als Waermetraegerfluid koennen im Untergrund in nicht waessriger Phase vorliegende Schadstoffe hauptsaechlich wegen der erhoehten Dampfdruecke in die Gasphase ueberfuehrt, ueber eine Bodenluftabsaugung an die Oberflaeche transportiert und dann einer weiteren Behandlung zugefuehrt werden. Zielsetzung eines zweistufigen Forschungsvorhabens war die systematische Entwicklung einer thermischen In-situ-Sanierungstechnologie unter

  14. Combined use of 15N and 18O of nitrate and 11B to evaluate nitrate contamination in groundwater

    International Nuclear Information System (INIS)

    Isotopic composition of NO3 (δ 15NNO3 and δ 18ONO3) and B (δ 11B) were used to evaluate NO3 contamination and identify geochemical processes occurring in a hydrologically complex Basin and Range valley in northern Nevada with multiple potential sources of NO3. Combined use of these isotopes may be a useful tool in identifying NO3 sources because NO3 and B co-migrate in many environmental settings, their isotopes are fractionated by different environmental processes, and because wastewater and fertilizers may have distinct isotopic signatures for N and B. The principal cause of elevated NO3 concentrations in residential parts of the study area is wastewater and not natural NO3 or fertilizers. This is indicated by some samples with elevated NO3 concentrations plotting along δ 15NNO3 and NO3 mixing lines between natural NO3 from the study area and theoretical septic-system effluent. This conclusion is supported by the presence of caffeine in one sample and the absence of samples with elevated NO3 concentrations that fall along mixing lines between natural NO3 and theoretical percolate below fertilized lawns. Nitrogen isotopes alone could not be used to determine NO3 sources in several wells because denitrification blurred the original isotopic signatures. The range of δ 11B values in native ground water in the study area (-8.2%o to +21.2%o) is large. The samples with the low δ 11B values have a geochemical signature characteristic of hydrothermal systems. Physical and chemical data suggest B is not being strongly fractionated by adsorption onto clays. δ 11B values from local STP effluent (-2.7%o) and wash water from a domestic washing machine (-5.7%o) were used to plot mixing lines between wastewater and native ground water. In general, wells with elevated NO3 concentrations fell along mixing lines between wastewater and background water on plots of δ 11B against 1/B and Cl/B. Combined use of δ 15N and δ 11B in the study area was generally successful in

  15. Involvement of the ORNL Chemical Technology Division in contaminated air and water handling at the Three Mile Island Nuclear Power Station

    International Nuclear Information System (INIS)

    The President's Commission on the Accident at Three Mile Island requested that Oak Ridge National Laboratory (ORNL) generate documents concerning two areas in which ORNL personnel provided on-site assistance following the accident on March 28, 1979. These are: instrumentation diagnostics, and the treatment of radioactive wastes and liquid effluents stemming from the accident. This report describes the involvement of the ORNL Chemical Technology Division (CTD) in contaminated air and water handling at Three Mile Island

  16. Daily and hourly sourcing of metallic and mineral dust in urban air contaminated by traffic and coal-burning emissions

    Science.gov (United States)

    Moreno, T.; Karanasiou, A.; Amato, F.; Lucarelli, F.; Nava, S.; Calzolai, G.; Chiari, M.; Coz, E.; Artíñano, B.; Lumbreras, J.; Borge, R.; Boldo, E.; Linares, C.; Alastuey, A.; Querol, X.; Gibbons, W.

    2013-04-01

    A multi-analytical approach to chemical analysis of inhalable urban atmospheric particulate matter (PM), integrating particle induced X-ray emission, inductively coupled plasma mass spectrometry/atomic emission spectroscopy, chromatography and thermal-optical transmission methods, allows comparison between hourly (Streaker) and 24-h (High volume sampler) data and consequently improved PM chemical characterization and source identification. In a traffic hot spot monitoring site in Madrid (Spain) the hourly data reveal metallic emissions (Zn, Cu, Cr, Fe) and resuspended mineral dust (Ca, Al, Si) to be closely associated with traffic flow. These pollutants build up during the day, emphasizing evening rush hour peaks, but decrease (especially their coarser fraction PM2.5-10) after nocturnal road washing. Positive matrix factorization (PMF) analysis of a large Streaker database additionally reveals two other mineral dust components (siliceous and sodic), marine aerosol, and minor, transient events which we attribute to biomass burning (K-rich) and industrial (incinerator?) Zn, Pb plumes. Chemical data on 24-h filters allows the measurement of secondary inorganic compounds and carbon concentrations and offers PMF analysis based on a limited number of samples but using fuller range of trace elements which, in the case of Madrid, identifies the continuing minor presence of a coal combustion source traced by As, Se, Ge and Organic Carbon. This coal component is more evident in the city air after the change to the winter heating season in November. Trace element data also allow use of discrimination diagrams such as V/Rb vs. La/Ce and ternary plots to illustrate variations in atmospheric chemistry (such as the effect of Ce-emissions from catalytic converters), with Madrid being an example of a city with little industrial pollution, recently reduced coal emissions, but serious atmospheric contamination by traffic emissions.

  17. Combined effects of precipitation and air temperature on soil moisture in different land covers in a humid basin

    Science.gov (United States)

    Feng, Huihui; Liu, Yuanbo

    2015-12-01

    Soil moisture is a key variable in hydrological processes. Although the combined effects of multiple climatic factors in different land cover conditions are highly valuable for water resource management, a complete understanding of these effects remains unclear. This study used a cluster analysis approach to investigate the combined effects of precipitation and air temperature, rather than a single factor, in different land covers for an area over the Poyang Lake Basin in China from 2003 to 2009. Specifically, monthly soil moisture was classified into eight clusters according to the change in precipitation and air temperature; the clusters describe a range of climates from the extreme of wet-hot to that of dry-cold. For an individual climate factor, our results showed that the contribution of air temperature to soil moisture is greater than that of precipitation, and the effect of air temperature is more sensitive in different land covers. When considering the combined effects of precipitation and air temperature, soil moisture varies with land cover; however, the variation in a normal climate cluster is greater than in an extreme climate cluster. This indicated that land cover is the dominant factor in soil moisture variation in normal climatic conditions, whereas climate is the dominant factor in extreme conditions. As climate shifts from the wet-hot to the dry-cold cluster, soil moisture decreases for all land covers, with the minimum rate occurring in forest conditions. Meanwhile, soil moisture deficit and saturation are more likely to occur in grassland and forest areas, indicating that forest cover might mitigate drought. The results of this study provide an effective approach to investigate the combined effects of climate factors on soil moisture for various land covers in humid areas. This study also supports the management of water resources in changing climates.

  18. Air

    Science.gov (United States)

    ... house) Industrial emissions (like smoke and chemicals from factories) Household cleaners (spray cleaners, air fresheners) Car emissions (like carbon monoxide) *All of these things make up “particle pollution.” They mostly come from cars, trucks, buses, and ...

  19. Combination of biochar amendment and mycoremediation for polycyclic aromatic hydrocarbons immobilization and biodegradation in creosote-contaminated soil.

    Science.gov (United States)

    García-Delgado, Carlos; Alfaro-Barta, Irene; Eymar, Enrique

    2015-03-21

    Soils impregnated with creosote contain high concentrations of polycyclic aromatic hydrocarbons (PAH). To bioremediate these soils and avoid PAH spread, different bioremediation strategies were tested, based on natural attenuation, biochar application, wheat straw biostimulation, Pleurotus ostreatus mycoremediation, and the novel sequential application of biochar for 21 days and P. ostreatus 21 days more. Soil was sampled after 21 and 42 days after the remediation application. The efficiency and effectiveness of each remediation treatment were assessed according to PAH degradation and immobilization, fungal and bacterial development, soil eco-toxicity and legal considerations. Natural attenuation and biochar treatments did not achieve adequate PAH removal and soil eco-toxicity reduction. Biostimulation showed the highest bacterial development but low PAH degradation rate. Mycoremediation achieved the best PAH degradation rate and the lowest bioavailable fraction and soil eco-toxicity. This bioremediation strategy achieved PAH concentrations below Spanish legislation for contaminated soils (RD 9/2005). Sequential application of biochar and P. ostreatus was the second treatment most effective for PAH biodegradation and immobilization. However, the activity of P. ostreatus was increased by previous biochar application and PAH degradation efficiency was increased. Therefore, the combined strategy for PAH degradation have high potential to increase remediation efficiency. PMID:25506817

  20. Feasibility study to combine the evaluation of radiological and chemical-toxicological effects of old contaminated sites

    International Nuclear Information System (INIS)

    The uranium mining regions of the German Federal States Saxony, Thuringia and Saxony-Anhalt are contaminated by radionuclides and by chemical substances. For both, ionizing radiations and chemicals, concepts and models exists to assess possible health effects for the population living in such areas. However, these assessment models were developed independently for both kinds of contaminants. Therefore, the 9th Conference of the State Ministers for Environmental Protection have claimed that for the evaluation of contaminated sites the radiological and chemical contaminants should be integrated into a joint assessment. This feasibility study describes the state of the art of the concepts and models used for the evaluation of radiological and chemical contaminants. The similarities and differences of these evaluation methods are identified and discussed. Suggestions are made for an integrated assessment to standardize the evaluation of sites contaminated by radionuclides or chemicals. (orig.)

  1. Combined use of Mediterranean local resources for restoring TCE-Contaminated soils. The bioremediation effect of Dittrichia viscosa and vermicomposted olive wastes

    International Nuclear Information System (INIS)

    Trichloroethylene (TCE) and its metabolic intermediates are resistant to biodegradation in aerobic subsurface environments, which contributes to their persistence in soils and polluted groundwater. In this study, the combined action of Dittricha viscosa (L.) and vermicomposted olive waste for the remediation of a TCE-contaminated soil was analyzed. (Author)

  2. Research on establishment of emergency transportation of heavy-injured and radiation-exposed and contaminated patients. Toward rapid, contamination-preventive and safe land and air transportion

    International Nuclear Information System (INIS)

    The authors has continued researches on countermeasures against various disasters including nuclear or radiation accident. Present paper deals with the following items; (1) Significance of preparation of a manual on countermeasures against disasters in relation to medical drills, (2) Status and prospects of disaster simulations and disaster drills, (3) Promotion and education on medical knowledge when nuclear disasters occur, (4) Network system study of broad area medicines throughout the country. (5) Study on how to approach mental an psychological cares, (6) Specialities of radioactive contamination in the general contamination of NBC (Nuclear, Biological and Chemical) disasters, (7) New concept and preparation of triage tags, and (8) Queueing theory application to many patients in a hospital. (H. Yokoo)

  3. Air

    International Nuclear Information System (INIS)

    In recent years several regulations and standards for air quality and limits for air pollution were issued or are in preparation by the European Union, which have severe influence on the environmental monitoring and legislation in Austria. This chapter of the environmental control report of Austria gives an overview about the legal situation of air pollution control in the European Union and in specific the legal situation in Austria. It gives a comprehensive inventory of air pollution measurements for the whole area of Austria of total suspended particulates, ozone, volatile organic compounds, nitrogen oxides, sulfur dioxide, carbon monoxide, heavy metals, benzene, dioxin, polycyclic aromatic hydrocarbons and eutrophication. For each of these pollutants the measured emission values throughout Austria are given in tables and geographical charts, the environmental impact is discussed, statistical data and time series of the emission sources are given and legal regulations and measures for an effective environmental pollution control are discussed. In particular the impact of fossil-fuel power plants on the air pollution is analyzed. (a.n.)

  4. Combining high resolution vertical gradients and sequence stratigraphy to delineate hydrogeologic units for a contaminated sedimentary rock aquifer system

    Science.gov (United States)

    Meyer, Jessica R.; Parker, Beth L.; Arnaud, Emmanuelle; Runkel, Anthony C.

    2016-03-01

    Hydrogeologic units (HGUs), representing subsurface contrasts in hydraulic conductivity, form the basis for all conceptual and numerical models of groundwater flow. However, conventionally, delineation of these units relies heavily on data sets indirect with respect to hydraulic properties. Here, we use the spatial and temporal characteristics of the vertical component of hydraulic gradient (i.e., vertical gradient) as the primary line of evidence for delineating HGUs for Cambrian-Ordovician sedimentary rocks at a site in Dane County, Wisconsin. The site includes a 16 km2 area encompassing a 3 km long mixed organic contaminants plume. The vertical gradients are derived from hydraulic head profiles obtained using high resolution Westbay multilevel systems installed at 7 locations along two, orthogonal 4 km long cross-sections and monitoring to depths between 90 and 146 m with an average of 3-4 monitoring zones per 10 m. These vertical gradient cross-sections reveal 11 laterally extensive HGUs with contrasting vertical hydraulic conductivity (Kv). The position and thickness of the Kv contrasts are consistently associated with sequence stratigraphic features (maximum flooding intervals and sequence boundaries) distinguished at the site using cores and borehole geophysical logs. The same sequence stratigraphic features are also traceable across much of the Cambrian-Ordovician aquifer system of the Midwest US. The vertical gradients and sequence stratigraphy were arrived at independently and when combined provide a hydraulically calibrated sequence stratigraphic framework for the site. This framework provides increased confidence in the precise delineation and description of the nature of HGU contacts in each borehole, reduced uncertainty in interpolation of the HGUs between boreholes, and some capability to predict HGU boundaries and thickness in offsite areas where high resolution hydraulic data sets are not available. Consequently, this HGU conceptual model will

  5. Protein denaturation by combined effect of shear and air-liquid interface.

    Science.gov (United States)

    Maa, Y F; Hsu, C C

    1997-06-20

    The effect of shear alone on the aggregation of recombinant human growth hormone (rhGH) and recombinant human deoxyribonuclease (rhDNase) has been found to be insignificant. This study focused on the synergetic effect of shear and gas-liquid interface on these two model proteins. Two shearing systems, the concentric-cylinder shear device (CCSD) and the rotor/stator homogenizer, were used to generate high shear (> 10(6)) in aqueous solutions in the presence of air. High shear in the presence of an air-liquid interface had no major effect on rhDNase but caused rhGH to form noncovalent aggregates. rhGH aggregation was induced by the air-liquid interface and was found to increase with increasing protein concentration and the air-liquid interfacial area. The aggregation was irreversible and exhibited a first-order kinetics with respect to the protein concentration and air-liquid interfacial area. Shear and shear rate enhanced the interaction because of its continuous generation of new air-liquid interfaces. In the presence of a surfactant, aggregation could be delayed or prevented depending upon the type and the concentration of the surfactant. The effect of air-liquid interface on proteins at low shear was examined using a nitrogen bubbling method. We found that foaming is very detrimental to rhGH even though the shear involved is low. The use of anti-foaming materials could prevent rhGH aggregation during bubbling. The superior stability exhibited by rhDNase may be linked to the higher surface tension and lower foaming tendency of its aqueous solution. (c) 1997 John Wiley & Sons, Inc. Biotechnol Bioeng 54: 503-512, 1997. PMID:18636406

  6. Performance analysis of a direct expansion air dehumidification system combined with membrane-based total heat recovery

    Energy Technology Data Exchange (ETDEWEB)

    Liang, Cai-Hang; Zhang, Li-Zhi; Pei, Li-Xia [Key Laboratory of Enhanced Heat Transfer and Energy Conservation of Education Ministry, School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou 510640 (China)

    2010-09-15

    A direct expansion (DX) air dehumidification system is an efficient way to supply fresh and dry air to a built environment. It plays a key role in preventing the spread of respiratory disease like Swine flu (H1N1). To improve the efficiency of a conventional DX system in hot and humid regions, a new system of DX in combination with a membrane-based total heat exchanger is proposed. Air is supplied with dew points. A detailed mathematical modeling is performed. A cell-by-cell simulation technique is used to simulate its performances. A real prototype is built in our laboratory in South China University of Technology to validate the model. The effects of inlet air humidity and temperature, evaporator and condenser sizes on the system performance are investigated. The results indicate that the model can predict the system accurately. Compared to a conventional DX system, the air dehumidification rate (ADR) of the novel system is 0.5 times higher, and the coefficient of performance (COP) is 1 times higher. Furthermore, the system performs well even under harsh hot and humid weather conditions. (author)

  7. [Environmental investigation of ground water contamination at Wright-Patterson Air Force Base, Ohio]. Volume 3, Appendix A, Draft standard operating procedures and elements: Sampling and Analysis Plan (SAP): Phase 1, Task 4, Field Investigation, Draft

    Energy Technology Data Exchange (ETDEWEB)

    1991-10-01

    This report presents information concerning field procedures employed during the monitoring, well construction, well purging, sampling, and well logging at the Wright-Patterson Air Force Base. Activities were conducted in an effort to evaluate ground water contamination.

  8. Distribution of contaminants in the occupied zone of a room with personalized and displacement ventilation

    DEFF Research Database (Denmark)

    Cermak, Radim; Melikov, Arsen Krikor; Forejt, L.; Kovar, O.

    2004-01-01

    A distribution of contaminants from floor covering, exhaled air and human bioeffluents was examined in a mock-up of a typical two-person office by means of tracer-gases. The distribution was studied with two types of air terminal device for personalized ventilation combined with displacement vent...... ventilation. The results document that the distribution of contaminants depends to a great extent on the type and operation of personalized ventilation, as well as on the type and location of contaminant sources....

  9. Determining the bioavailability and toxicity of lead contamination to earthworms requires using a combination of physicochemical and biological methods

    International Nuclear Information System (INIS)

    This study aimed at assessing the bioavailability and toxicity of lead to Eisenia andrei in shooting range soils representing different land uses (forest, grassland, bullet plot). Soils contained 47–2398 mg Pb/kg dry weight (dw), but also had different pH-CaCl2 (3.2–6.8) and organic matter contents (3.8–13%). Therefore artificial soils with different pH and organic matter contents and two natural soils were included as control soils. Earthworms were exposed for 28 days and toxicity and uptake of Pb were related to total, water and 0.01 M CaCl2 extractable and porewater Pb concentrations as well as to soil characteristics. Pb uptake in the earthworms linearly increased with increasing soil concentrations. At >2000 mg Pb/kg dw and pH 3.3–3.5, high earthworm mortality with significant weight loss and complete inhibition of reproduction were recorded. At <1000 mg/kg dw, earthworm reproduction was more related to differences in pH and other soil characteristics than to Pb. -- Highlights: • Availability and earthworm toxicity of Pb determined in field-contaminated soils. • Earthworm toxicity of most-polluted soils explained from available Pb levels. • Earthworm response in less polluted soils mainly determined by soil pH. • Earthworm toxicity correlated with Pb uptake from the soil. • Soil properties explained differences in earthworm Pb uptake and effects. -- Combination of physicochemical and biological assays helped explaining Pb toxicity in shooting range soils from available Pb concentrations and soil characteristics

  10. PERFORMANCE OF AN AIR CLASSIFIER TO REMOVE LIGHT ORGANIC CONTAMINATION FROM ALUMINUM RECOVERED FROM MUNICIPAL WASTE BY EDDY CURRENT SEPARATION. TEST NO. 5.03, RECOVERY 1, NEW ORLEANS

    Science.gov (United States)

    The report describes a test in which aluminum cans recovered from municipal waste, together with known amounts of contaminant, were processed by a 'zig-zag' vertical air classifier to remove aerodynamically light contaminant. Twelve test runs were conducted; the proportions of co...

  11. Characterization of chlorinated solvent contamination in limestone using innovative FLUTe® technologies in combination with other methods in a line of evidence approach.

    Science.gov (United States)

    Broholm, Mette M; Janniche, Gry S; Mosthaf, Klaus; Fjordbøge, Annika S; Binning, Philip J; Christensen, Anders G; Grosen, Bernt; Jørgensen, Torben H; Keller, Carl; Wealthall, Gary; Kerrn-Jespersen, Henriette

    2016-06-01

    Characterization of dense non-aqueous phase liquid (DNAPL) source zones in limestone aquifers/bedrock is essential to develop accurate site-specific conceptual models and perform risk assessment. Here innovative field methods were combined to improve determination of source zone architecture, hydrogeology and contaminant distribution. The FACT™ is a new technology and it was applied and tested at a contaminated site with a limestone aquifer, together with a number of existing methods including wire-line coring with core subsampling, FLUTe® transmissivity profiling and multilevel water sampling. Laboratory sorption studies were combined with a model of contaminant uptake on the FACT™ for data interpretation. Limestone aquifers were found particularly difficult to sample with existing methods because of core loss, particularly from soft zones in contact with chert beds. Water FLUTe™ multilevel groundwater sampling (under two flow conditions) and FACT™ sampling and analysis combined with FLUTe® transmissivity profiling and modeling were used to provide a line of evidence for the presence of DNAPL, dissolved and sorbed phase contamination in the limestone fractures and matrix. The combined methods were able to provide detailed vertical profiles of DNAPL and contaminant distributions, water flows and fracture zones in the aquifer and are therefore a powerful tool for site investigation. For the limestone aquifer the results indicate horizontal spreading in the upper crushed zone, vertical migration through fractures in the bryozoan limestone down to about 16-18m depth with some horizontal migrations along horizontal fractures within the limestone. Documentation of the DNAPL source in the limestone aquifer was significantly improved by the use of FACT™ and Water FLUTe™ data. PMID:27116640

  12. Characterization of chlorinated solvent contamination in limestone using innovative FLUTe® technologies in combination with other methods in a line of evidence approach

    Science.gov (United States)

    Broholm, Mette M.; Janniche, Gry S.; Mosthaf, Klaus; Fjordbøge, Annika S.; Binning, Philip J.; Christensen, Anders G.; Grosen, Bernt; Jørgensen, Torben H.; Keller, Carl; Wealthall, Gary; Kerrn-Jespersen, Henriette

    2016-06-01

    Characterization of dense non-aqueous phase liquid (DNAPL) source zones in limestone aquifers/bedrock is essential to develop accurate site-specific conceptual models and perform risk assessment. Here innovative field methods were combined to improve determination of source zone architecture, hydrogeology and contaminant distribution. The FACT™ is a new technology and it was applied and tested at a contaminated site with a limestone aquifer, together with a number of existing methods including wire-line coring with core subsampling, FLUTe® transmissivity profiling and multilevel water sampling. Laboratory sorption studies were combined with a model of contaminant uptake on the FACT™ for data interpretation. Limestone aquifers were found particularly difficult to sample with existing methods because of core loss, particularly from soft zones in contact with chert beds. Water FLUTe™ multilevel groundwater sampling (under two flow conditions) and FACT™ sampling and analysis combined with FLUTe® transmissivity profiling and modeling were used to provide a line of evidence for the presence of DNAPL, dissolved and sorbed phase contamination in the limestone fractures and matrix. The combined methods were able to provide detailed vertical profiles of DNAPL and contaminant distributions, water flows and fracture zones in the aquifer and are therefore a powerful tool for site investigation. For the limestone aquifer the results indicate horizontal spreading in the upper crushed zone, vertical migration through fractures in the bryozoan limestone down to about 16-18 m depth with some horizontal migrations along horizontal fractures within the limestone. Documentation of the DNAPL source in the limestone aquifer was significantly improved by the use of FACT™ and Water FLUTe™ data.

  13. Performance assessment and optimization of a combined heat and power system based on compressed air energy storage system and humid air turbine cycle

    International Nuclear Information System (INIS)

    Highlights: • A combined heat and power system based on CAES and HAT is proposed. • The design and modeling of the CAES–HAT based CHP system are laid out. • The performance assessment of the proposed system is carried out. • The system optimization is conducted to decide the maximum conditions. - Abstract: Renewable energy based power sources have grown rapidly in the past few years owing to the dual constraint of climate change and pollution control. Compressed air energy storage (CAES), as a large-scale energy storage system (ESS) technology, has huge potential to manage the intermittent renewable energy based power sources effectively. However, the compression heat generated during charge and waste heat carried in turbine exhaust during discharge are not fully recuperated in current stage. A combined heat and power (CHP) system consisting of a CAES system and a humid air turbine (HAT) system is proposed to utilize the both types of heat energy. The proposed system can boost the power output, enhance performance and improve efficiency through a simultaneous supply of power and heat. The thermodynamic analysis shows that the expansion train power can be improved about 26% compared with the conventional CAES system. The parametric analysis reveals that the exergy efficiency increases with the turbine inlet temperature (TIT) of high pressure turbine (HPT) and inlet pressure of low pressure turbine (LPT), but decreases with the TIT of LPT, L/G ratio and dry air inlet temperature of saturator. Meanwhile, the system optimization is carried out via particle swarm optimization (PSO) to determine the maximum power and exergy efficiency conditions

  14. Remediation of highly contaminated soils from an industrial site by employing a combined treatment with exogeneous humic substances and oxidative biomimetic catalysis

    Energy Technology Data Exchange (ETDEWEB)

    Sannino, Filomena, E-mail: fsannino@unina.it [Dipartimento di Agraria, Università di Napoli “Federico II”, Via Università 100, 80055 Portici (Italy); Spaccini, Riccardo [Dipartimento di Agraria, Università di Napoli “Federico II”, Via Università 100, 80055 Portici (Italy); Centro Interdipartimentale di Ricerca sulla Risonanza Magnetica Nucleare per l’Ambiente, l’Agro-Alimentare ed i Nuovi Materiali (CERMANU), Via Università 100, 80055 Portici (Italy); Savy, Davide [Dipartimento di Agraria, Università di Napoli “Federico II”, Via Università 100, 80055 Portici (Italy); Piccolo, Alessandro [Dipartimento di Agraria, Università di Napoli “Federico II”, Via Università 100, 80055 Portici (Italy); Centro Interdipartimentale di Ricerca sulla Risonanza Magnetica Nucleare per l’Ambiente, l’Agro-Alimentare ed i Nuovi Materiali (CERMANU), Via Università 100, 80055 Portici (Italy)

    2013-10-15

    Highlights: • Remediation of two polluted soils from a highly contaminated industrial site in Italy. • Restoration of soil quality by introducing additional carbon into polluted soil with humic matter amendments. • Detoxification of contaminants by covalent binding to humic molecules. • Prevention of environmental transport of pollutants. -- Abstract: Remediation of two polluted soils from a northern Italian industrial site heavily contaminated with organic contaminants was attempted here by subjecting soils first to addition with an exogenous humic acid (HA), and, then, to an oxidation reaction catalyzed by a water-soluble iron-porphyrin (FeP). An expected decrease of detectable organic pollutants (>50%) was already observed when soils were treated only with the H{sub 2}O{sub 2} oxidant. This reduction was substantially enhanced when oxidation was catalyzed by iron-porphyrin (FeP + H{sub 2}O{sub 2}) and the largest effect was observed for the most highly polluted soil. Even more significant was the decrease in detectable pollutants (70–90%) when soils were first amended with HA and then subjected to the FeP + H{sub 2}O{sub 2} treatment. This reduction in extractable pollutants after the combined HA + FeP + H{sub 2}O{sub 2} treatment was due to formation of covalent C-C and C-O-C bonds between soil contaminants and amended humic molecules. Moreover, the concomitant detection of condensation products in soil extracts following FeP addition confirmed the occurrence of free-radical coupling reactions catalyzed by FeP. These findings indicate that a combined technique based on the action of both humic matter and a metal-porhyrin catalyst, may become useful to quantitatively reduce the toxicity of heavily contaminated soils and prevent the environmental transport of pollutants.

  15. Remediation of highly contaminated soils from an industrial site by employing a combined treatment with exogeneous humic substances and oxidative biomimetic catalysis

    International Nuclear Information System (INIS)

    Highlights: • Remediation of two polluted soils from a highly contaminated industrial site in Italy. • Restoration of soil quality by introducing additional carbon into polluted soil with humic matter amendments. • Detoxification of contaminants by covalent binding to humic molecules. • Prevention of environmental transport of pollutants. -- Abstract: Remediation of two polluted soils from a northern Italian industrial site heavily contaminated with organic contaminants was attempted here by subjecting soils first to addition with an exogenous humic acid (HA), and, then, to an oxidation reaction catalyzed by a water-soluble iron-porphyrin (FeP). An expected decrease of detectable organic pollutants (>50%) was already observed when soils were treated only with the H2O2 oxidant. This reduction was substantially enhanced when oxidation was catalyzed by iron-porphyrin (FeP + H2O2) and the largest effect was observed for the most highly polluted soil. Even more significant was the decrease in detectable pollutants (70–90%) when soils were first amended with HA and then subjected to the FeP + H2O2 treatment. This reduction in extractable pollutants after the combined HA + FeP + H2O2 treatment was due to formation of covalent C-C and C-O-C bonds between soil contaminants and amended humic molecules. Moreover, the concomitant detection of condensation products in soil extracts following FeP addition confirmed the occurrence of free-radical coupling reactions catalyzed by FeP. These findings indicate that a combined technique based on the action of both humic matter and a metal-porhyrin catalyst, may become useful to quantitatively reduce the toxicity of heavily contaminated soils and prevent the environmental transport of pollutants

  16. Improving the exergy efficiency of a cryogenic air separation unit as part of an integrated gasification combined cycle

    International Nuclear Information System (INIS)

    Graphical abstract: Display Omitted Highlights: ► Cryogenic air separation as part of an integrated gasification combined cycle. ► Considerable improvements in the exergy efficiency of a two-column design. ► Heating the separation products using heat of compression. ► Improving heat integration of the columns using heat-integrated distillation stages. - Abstract: The efficiency of a two-column cryogenic ASU (air separation unit) that is part of an IGCC (integrated gasification combined cycle) can be increased significantly by making better use of the heat of compression and by improving the heat integration of the distillation columns. The rational exergy efficiency of the ASU, which is defined as the desired increase in exergy content of the products divided by the amount of work that is added to the process, can be increased from 35% to over 70%. The exergy destruction per amount of feed is reduced with 1.6 kJ/mol air, corresponding to a 0.74% increase in the net electric efficiency of the IGCC. The efficiencies are expected to increase even further because the full potential of using heat-integrated distillation columns is not yet achieved.

  17. Cherenkov counter of extensive air showers for combined operation with the neutrino telescope NT-200

    International Nuclear Information System (INIS)

    The Baikal NT-200 neutrino telescope consists of 192 optical modules based on the Quasar-370 hybrid photodetectors. To study the angular resolution of NT-200 neutrino telescope one has developed the Cherenkov counter of extensive air showers with 1 deg angular resolution. Paper describes the electron structure of the facility made in terms of the CAMAC standard. One evaluates the measurement error for time intervals depending on the amplitude of output signals of photodetector. The counting rate of coinciding events of the Cherenkov counter for extensive air showers and of NT-200 deep-sea neutrino telescope constitutes about 0.5 min-1.Measuring of time interval between the trigger signals of the neutrino telescope and of the Cherenkov counter enables to suppress efficiently random coincidences and to obtain additional information on the muon trajectory

  18. A hybrid thermal management system for lithium ion batteries combining phase change materials with forced-air cooling

    International Nuclear Information System (INIS)

    Highlights: • Heat accumulation in PCM causes failures of passive thermal management systems. • The introduction of forced air convection improves the reliability of PCMs. • Temperature distribution in the hybrid system remains uniform. • Active cooling and PCMs play separate roles in battery thermal management. • Numerical results agree with experiment data and give theoretic insights. - Abstract: Passive thermal management systems using phase change materials (PCMs) provides an effective solution to the overheating of lithium ion batteries. But this study shows heat accumulation in PCMs caused by the inefficient cooling of air natural convection leads to thermal management system failures: The temperature in a battery pack operating continuously outranges the safety limit of 60 °C after two cycles with discharge rate of 1.5 C and 2 C. Here a hybrid system that integrates PCMs with forced air convection is presented. This combined system successfully prevents heat accumulation and maintains the maximum temperature under 50 °C in all cycles. Study on airspeed effects reveals that thermo-physical properties of PCMs dictate the maximum temperature rise and temperature uniformity in the battery pack, while forced air convection plays a critical role in recovering thermal energy storage capacity of PCMs. A numerical study is also carried out and validated with experiment data, which gives theoretic insights on thermo-physical changes in this hybrid battery thermal management system

  19. Combination of experimental and simulated small scale solar air-conditioning system

    OpenAIRE

    Thomas, Sébastien; Hennaut, Samuel; Andre, Philippe

    2010-01-01

    It is now clearly assumed that solar assisted air conditioning is able to decrease CO2 production of building operation. One way to evaluate the energy savings potential is the simulation of airconditioning systems. On the other hand, it is also crucial to assess system performance by experimentations. The operation of a solar cooling system in its real environment is considered here. The objective is to evaluate if sun radiation in our region (Western Europe – Belgium) in summ...

  20. Polychlorinated biphenyls (PCBs) in indoor air originating from sealants in contaminated and uncontaminated apartments within the same housing estate

    DEFF Research Database (Denmark)

    Frederiksen, Marie; Meyer, Harald William; Ebbehøj, Niels Erik;

    2012-01-01

    Twenty-four congeners of polychlorinated biphenyls (PCBs) were measured in 83 air samples and 20 elastic sealants samples of apartments with PCB-containing sealants. In addition, PCBs were measured in 21 air samples from reference apartments located in an uncontaminated section of the same estate...

  1. Contamination of the air and other environmental samples of the Ulm region by radioactive fission products after the accident of the Chernobyl reactor

    International Nuclear Information System (INIS)

    Since April 30, 1986, the radioactivity of the fission products released by the accident of the Chernobyl reactor has been measured in the air of the city of Ulm. The airborne dust samples were collected with flow calibrated samplers on cellulose acetate membrane filters and counted with a high resolution gamma ray spectrometer. Later on, the radioactivity measurements were expanded to other relevant environmental samples contaminated by radioactive atmospheric precipitates including grass, spruce needles, mosses, lichens, various kinds of food, drinking water, asphalt and concrete surface layers, municipal sewage sludge and sewage sludge ash. This paper reports the obtained results. (orig.)

  2. COP Prediction of an ejector refrigeration cycle combined with a vapour compression cycle for automotive air conditioning

    Directory of Open Access Journals (Sweden)

    Nat Suvarnakuta

    2014-03-01

    Full Text Available This paper presents the COP prediction of an ejector refrigeration cycle combined with a vapour compression cycle for automotive air conditioning. Using computational fluid dynamics (CFD technique, the performance of an ejector was analyzed in term of the entrainment ratio (Rm and critical back pressure (CBP. The results from this study were compared with a previous study of combined ejector refrigeration system for automotive air conditioning application [1] which the entrainment ratio (Rm were predicted from one-dimensional (1-D equation. The performance of an ejector (Rm and CBP from CFD and onedimensional method were analyzed and used as database for a mathematical modeling. In order to predict the COP of the combined system, a set of mathematical equations was developed using EES. The operating conditions are chosen accordingly as, intercooler temperature between 15 ๐ C and 25 ๐ C, condenser temperature equal to 35 ๐ C and evaporator temperature equal to 5 ๐ C. However, when generator temperatures are 80 ๐ C, 85 ๐ C and 90 ๐ C, the results showed average relative errors of the COP of an ejector refrigeration cycle (COPej, between CFD and 1-D are 44.64%, 50.47% and 59.68% respectively, and between CFD and 1-D NEW are 1.54%, 0.08% and 6.49% respectively.

  3. Procedures for addressing uncertainty and variability in exposure to characterize potential health risk from trichloroethylene contaminated groundwater at Beale Air Force Base in California; TOPICAL

    International Nuclear Information System (INIS)

    This study was designed to accomplish two objectives. The first was to provide to the US Air Force and the regulatory community quantitative procedures that they might want to consider using for addressing uncertainty and variability in exposure to better characterize potential health risk. Such methods could be used at sites where populations may now or in the future be faced with using groundwater contaminated with low concentrations of the chemical trichloroethylene (TCE). The second was to illustrate and explain the application of these procedures with respect to available data for TCE in ground water beneath an inactive landfill site that is undergoing remediation at Beale Air Force Base in California. The results from this illustration provide more detail than the more traditional conservative deterministic, screening-level calculations of risk, also computed for purposes of comparison. Application of the procedures described in this report can lead to more reasonable and equitable risk-acceptability criteria for potentially exposed populations at specific sites

  4. Procedures for addressing uncertainty and variability in exposure to characterize potential health risk from trichloroethylene contaminated groundwater at Beale Air Force Base in California

    Energy Technology Data Exchange (ETDEWEB)

    Bogen, K T; Daniels, J I; Hall, L C

    1999-09-01

    This study was designed to accomplish two objectives. The first was to provide to the US Air Force and the regulatory community quantitative procedures that they might want to consider using for addressing uncertainty and variability in exposure to better characterize potential health risk. Such methods could be used at sites where populations may now or in the future be faced with using groundwater contaminated with low concentrations of the chemical trichloroethylene (TCE). The second was to illustrate and explain the application of these procedures with respect to available data for TCE in ground water beneath an inactive landfill site that is undergoing remediation at Beale Air Force Base in California. The results from this illustration provide more detail than the more traditional conservative deterministic, screening-level calculations of risk, also computed for purposes of comparison. Application of the procedures described in this report can lead to more reasonable and equitable risk-acceptability criteria for potentially exposed populations at specific sites.

  5. Comparison of monitored natural attenuation with other alternatives for remediation of contaminated groundwater at Naval Air Station (NAS) Fallon, USA

    International Nuclear Information System (INIS)

    Monitored natural attenuation (MNA) and several other potential alternatives were evaluated for remediation of dissolved-phase groundwater contamination at Site 1, the former crash crew training area at NAS Fallon. The contaminants of concern at the site are petroleum hydrocarbon constituents and chlorinated ethenes. Remedial action objectives were developed using a conceptual model for the site, applicable regulatory action levels, site contaminants, and a point-of-compliance. A field evaluation of MNA was conducted at Site 1. Monitored natural attenuation was compared to other potential remedial alternatives for achieving the RAOs including: plume containment using pumping wells, interceptor drain, or slurry wall; and active restoration with enhanced in situ bioremediation, pump and treat using wells, or pump and treat using an interceptor drain. Alternatives were comparatively evaluated using three criteria, effectiveness, ability to implement and cost. The evaluation indicates that MNA is a viable and cost-effective remedial alternative for Site 1

  6. A Next Generation Air Monitor: Combining Orion and ISS Requirements for a Common Major Constituent Analyzer

    Science.gov (United States)

    Burchfield, David E.; Tissandier, Michael; Niu, William Hsein-Chi; Lewis, John F.

    2013-01-01

    The Major Constituent Analyzer (MCA) is a mass spectrometer-based instrument designed to provide critical monitoring of six major atmospheric constituents; nitrogen, oxygen, hydrogen, carbon dioxide, methane, and water vapor on-board the International Space Station. The analyzer has been an integral part of the Environmental Control and Life Support System (ECLSS) since the station went on-line. The Orion Air Monitor (OAM) was derived from the MCA and heavily optimized for reduced mass, lower power, faster water vapor response, and maintenance-free operation. The resulting OAM is approximately the size of the analyzer portion of the MCA, orbital-replacement unit 02 (ORU 02), while incorporating the functions of three other modules: Data Processing and Communication (ORU 01), Verification Gas Assembly (ORU 08), and Low Voltage Power Supply (ORU 04). The overlap in MCA and OAM requirements makes it possible to derive a common Air Monitor design that spans both applications while minimally impacting the weight and power limits imposed by the Multipurpose Crew Vehicle (MPCV). Benefits to ISS include the retirement of ORUs 01, 04, and 08, reducing up-mass and eliminating EEE parts obsolescence issues through the extended ISS mission phases. Benefits to MPCV and future deployed habitats under the Constellation program include greater interchangeability across ECLSS subsystems. This paper discusses the results of the requirements development study, where a superset of ISS and Orion air monitoring requirements were distilled; evaluated against increases in OAM functionality, mass, and power; and traded-off where possible using simple operating mode modifications. A system architecture and preliminary design addressing the common requirements will be presented.

  7. Combining in situ chemical oxidation, stabilization, and anaerobic bioremediation in a single application to reduce contaminant mass and leachability in soil

    Energy Technology Data Exchange (ETDEWEB)

    Cassidy, Daniel P., E-mail: daniel.cassidy@wmich.edu [Department of Geosciences, Western Michigan University, Kalamazoo, MI 49008 (United States); Srivastava, Vipul J., E-mail: vipul.srivastava@ch2m.com [CH2M HILL, 125S Wacker, Ste 3000, Chicago, IL 60606 (United States); Dombrowski, Frank J., E-mail: frank.dombrowski@we-energies.com [We Energies, 333W Everett St., A231, Milwaukee, WI 53203 (United States); Lingle, James W., E-mail: jlingle@epri.com [Electric Power Research Institute (EPRI), 4927W Willow Road, Brown Deer, WI 53223 (United States)

    2015-10-30

    Highlights: • Portland cement and lime activated persulfate by increasing pH and temperature. • Chemical oxidation achieved BTEX and PAH removal ranging from 55% to 75%. • Activating persulfate with ISS amendments reduced leachability more than NaOH. • Native sulfate-reducing bacteria degraded PAHs within weeks after ISCO finished. • ISCO, ISS, and anaerobic bioremediation were combined in a single application. - Abstract: Laboratory batch reactors were maintained for 32 weeks to test the potential for an in situ remedy that combines chemical oxidation, stabilization, and anaerobic bioremediation in a single application to treat soil from a manufactured gas plant, contaminated with polycyclic aromatic hydrocarbons (PAH) and benzene, toluene, ethylbenzene, and xylenes (BTEX). Portland cement and slaked lime were used to activate the persulfate and to stabilize/encapsulate the contaminants that were not chemically oxidized. Native sulfate-reducing bacteria degraded residual contaminants using the sulfate left after persulfate activation. The ability of the combined remedy to reduce contaminant mass and leachability was compared with NaOH-activated persulfate, stabilization, and sulfate-reducing bioremediation as stand-alone technologies. The stabilization amendments increased pH and temperature sufficiently to activate the persulfate within 1 week. Activation with both stabilization amendments and NaOH removed between 55% and 70% of PAH and BTEX. However, combined persulfate and stabilization significantly reduced the leachability of residual BTEX and PAH compared with NaOH activation. Sulfide, 2-naphthoic acid, and the abundance of subunit A of the dissimilatory sulfite reductase gene (dsrA) were used to monitor native sulfate-reducing bacteria, which were negatively impacted by activated persulfate, but recovered completely within weeks.

  8. Combining in situ chemical oxidation, stabilization, and anaerobic bioremediation in a single application to reduce contaminant mass and leachability in soil

    International Nuclear Information System (INIS)

    Highlights: • Portland cement and lime activated persulfate by increasing pH and temperature. • Chemical oxidation achieved BTEX and PAH removal ranging from 55% to 75%. • Activating persulfate with ISS amendments reduced leachability more than NaOH. • Native sulfate-reducing bacteria degraded PAHs within weeks after ISCO finished. • ISCO, ISS, and anaerobic bioremediation were combined in a single application. - Abstract: Laboratory batch reactors were maintained for 32 weeks to test the potential for an in situ remedy that combines chemical oxidation, stabilization, and anaerobic bioremediation in a single application to treat soil from a manufactured gas plant, contaminated with polycyclic aromatic hydrocarbons (PAH) and benzene, toluene, ethylbenzene, and xylenes (BTEX). Portland cement and slaked lime were used to activate the persulfate and to stabilize/encapsulate the contaminants that were not chemically oxidized. Native sulfate-reducing bacteria degraded residual contaminants using the sulfate left after persulfate activation. The ability of the combined remedy to reduce contaminant mass and leachability was compared with NaOH-activated persulfate, stabilization, and sulfate-reducing bioremediation as stand-alone technologies. The stabilization amendments increased pH and temperature sufficiently to activate the persulfate within 1 week. Activation with both stabilization amendments and NaOH removed between 55% and 70% of PAH and BTEX. However, combined persulfate and stabilization significantly reduced the leachability of residual BTEX and PAH compared with NaOH activation. Sulfide, 2-naphthoic acid, and the abundance of subunit A of the dissimilatory sulfite reductase gene (dsrA) were used to monitor native sulfate-reducing bacteria, which were negatively impacted by activated persulfate, but recovered completely within weeks

  9. Sensory and Physiological Effects on Humans of Combined Exposures to Air Temperatures and Volatile Organic Compounds

    DEFF Research Database (Denmark)

    Mølhave, Lars; Liu, Zunyong; Jørgensen, Anne Hempel;

    1993-01-01

    cross-sectional areas and nasal volumes, as measured by acoustic rhinometry, were shown to decrease with decreasing temperature and increasing VOC exposure. Temperature and pollutant exposures affected air quality, the need for more ventilation, skin humidity on the forehead, sweating, acute sensory...... irritation and possibly watering eyes in an additive way. Interactions were found for odor intensity (p = 0.1), perceived facial skin temperature and dryness, general well-being, tear film stability, and nasal cavity dimension. The presence of interactions implies that in the future guidelines for acceptable...

  10. Spectroscopic Properties of Benzene at the Air-Ice Interface: A Combined Experimental-Computational Approach

    Czech Academy of Sciences Publication Activity Database

    Kania, R.; Malongwe, J. K.; Nachtigallová, Dana; Krousko, J.; Gladich, I.; Roeselová, Martina; Heger, D.; Klán, P.

    2014-01-01

    Roč. 118, č. 35 (2014), s. 7535-7547. ISSN 1089-5639 R&D Projects: GA ČR GAP208/12/1318; GA ČR(CZ) GAP208/10/1724; GA MŠk(CZ) LH11021 Grant ostatní: GA ČR(CZ) GAP503/10/0947; GA MŠk(CZ) LO1214; European Social Fund(XE) CZ.1.07/2.3.00/30.0037 Institutional support: RVO:61388963 Keywords : density functional theory * polycyclic aromatic hydrocarbons * atmospheric air/ice interfaces Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 2.693, year: 2014

  11. The passive control of air pollution exposure in Dublin, Ireland: A combined measurement and modelling case study

    International Nuclear Information System (INIS)

    This study investigates the potential real world application of passive control systems to reduce personal pollutant exposure in an urban street canyon in Dublin, Ireland. The implementation of parked cars and/or low boundary walls as a passive control system has been shown to minimise personal exposure to pollutants on footpaths in previous investigations. However, previous research has been limited to generic numerical modelling studies. This study combines real-time traffic data, meteorological conditions and pollution concentrations, in a real world urban street canyon before and after the implementation of a passive control system. Using a combination of field measurements and numerical modelling this study assessed the potential impact of passive controls on personal exposure to nitric oxide (NO) concentrations in the street canyon in winter conditions. A calibrated numerical model of the urban street canyon was developed, taking into account the variability in traffic and meteorological conditions. The modelling system combined the computational fluid dynamic (CFD) simulations and a semi-empirical equation, and demonstrated a good agreement with measured field data collected in the street canyon. The results indicated that lane distribution, fleet composition and vehicular turbulence all affected pollutant dispersion, in addition to the canyon geometry and local meteorological conditions. The introduction of passive controls displayed mixed results for improvements in air quality on the footpaths for different wind and traffic conditions. Parked cars demonstrated the most comprehensive passive control system with average improvements in air quality of up to 15% on the footpaths. This study highlights the potential of passive controls in a real street canyon to increase dispersion and improve air quality at street level. - Highlights: • Parked cars and LBWs were assessed as passive controls in an urban street canyon. • The calibrated model combined CFD

  12. Measure Guideline: Combination Forced-Air Space and Tankless Domestic Hot Water Heating Systems

    Energy Technology Data Exchange (ETDEWEB)

    Rudd, A.

    2012-08-01

    This document describes design and application guidance for combination space and tankless domestic hot water heating systems (combination systems) used in residential buildings, based on field evaluation, testing, and industry meetings conducted by Building Science Corporation. As residential building enclosure improvements continue to drive heating loads down, using the same water heating equipment for both space heating and domestic water heating becomes attractive from an initial cost and space-saving perspective. This topic is applicable to single- and multi-family residential buildings, both new and retrofitted.

  13. Measure Guideline. Combination Forced-Air Space and Tankless Domestic Hot Water Heating Systems

    Energy Technology Data Exchange (ETDEWEB)

    Rudd, Armin [Building Science Corporation Industry Team (BSC), Somerville, MA (United States)

    2012-08-01

    This document describes design and application guidance for combination space and tankless domestic hot water heating systems (combination systems) used in residential buildings, based on field evaluation, testing, and industry meetings conducted by Building Science Corporation. As residential building enclosure improvements continue to drive heating loads down, using the same water heating equipment for both space heating and domestic water heating becomes attractive from an initial cost and space-saving perspective. This topic is applicable to single- and multi-family residential buildings, both new and retrofitted.

  14. Combined Ground and Space-Based Measurements of Air Quality during the London Olympic Games 2012

    Science.gov (United States)

    Graves, R. R.; Leigh, R. J.; Singh Anand, J.; McNally, M.; Lawrence, J.; Remedios, J.; Monks, P. S.

    2012-12-01

    During July and August 2012 the Summer Olympic Games were held in London. During this period, unusually high levels of traffic and visitors to the city were expected, it is important to understand the effect this had on the air quality in London during this period. To this end three novel CityScan instruments were installed in London from the 20th July though to the end of September; affording the unique opportunity to monitor the spatial and vertical structure of nitrogen dioxide within the boundary layer in unprecedented detail. The deployment was included as part of the large NERC funded ClearfLo project (Clean Air for London) involving many other institutions and complementary measurement techniques. CityScan is a Hemispherical Scanning Imaging Differential Optical Absorption Spectrometer (HSI-DOAS) which is has been optimised to measure concentrations of nitrogen dioxide. CityScan has a 95° field of view (FOV) between the zenith and 5° below the horizon. Across this FOV there are 128 resolved elements which are measured concurrently, the spectrometer is rotated azimuthally 1° per second providing full hemispherical coverage every 6 minutes. CityScan measures concentrations of nitrogen dioxide over specific lines of sight and due to the extensive field of view of the instrument this produces measurements which are representative over city-wide scales. Nitrogen dioxide is an important air pollutant which is produced in all combustion processes and can reduce lung function; especially in sensitised individuals. These instruments aim to bridge the gap in spatial scales between point source measurements of air quality and satellite measurements of air quality offering additional information on emissions, transport and the chemistry of nitrogen dioxide. More information regarding the CityScan technique can be found at http://www.leos.le.ac.uk/aq/index.html. The first of the three CityScan instruments was located in North Kensington, the second in Soho and third

  15. Characterization of dissolved organic matter in landfill leachate during the combined treatment process of air stripping, Fenton, SBR and coagulation

    International Nuclear Information System (INIS)

    Highlights: • DOM fractions spectra analysis during the whole treatment process. • Efficient method was achieved to remove organic matters in landfill leachate. • Molecular weight distribution and fractions were discussed. - Abstract: A combined treatment process of air stripping + Fenton + sequencing batch reactor (SBR)+ coagulation was performed to remove the pollutants in landfill leachate. Molecular weight (MW) distribution and fractions of dissolved organic matter (DOM) were discussed to study the characteristics. The experiment showed that the removal rate of chemical oxygen demand (COD), five day biological oxygen demand (BOD5) and ammonia nitrogen (NH3−N) by the combined process were 92.8%, 87.8% and 98.0%, respectively. Humic acid (HA) and fulvic acid (FA) were the main fractions in raw leachate with 81.8% of the total COD concentration, while hydrophilic organic matter (HyI) was the dominant fraction in the final effluent of the combined process with 63.5% of the total COD concentration. After the combined treatment process, the removal rate of DOM and fractions HA, FA, HyI were 91.9%, 97.1%, 95.8% and 71.7%, respectively. Organic matters of MW < 2 k and MW > 100 k were removed with 90.5% and 97.9% COD concentration after the treatment. The ultraviolet–visible spectra (UV–vis), Fourier transform infrared spectra (FTIR) and three-dimensional excitation-emission matrices spectra (EEMs) indicated that benzene materials and phenol compounds were preferentially removed in air stripping. High MW matters, aromatic rings, conjugated moieties and some functional groups were mainly removed by Fenton. While small MW fractions, carboxylic acids, alcohols and protein-like materials were preferentially biodegraded via SBR. Fulvic-like and humic-like materials were mainly destroyed via Fenton oxidation and coagulation

  16. Characterization of dissolved organic matter in landfill leachate during the combined treatment process of air stripping, Fenton, SBR and coagulation

    Energy Technology Data Exchange (ETDEWEB)

    Liu, ZhiPing, E-mail: liulqs@163.com [Key Laboratory of Three Gorges Reservoir Region’s Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045 (China); Faculty of Urban Construction and Environmental Engineering, Chongqing University, Chongqing 400020 (China); Wu, WenHui; Shi, Ping [Faculty of Urban Construction and Environmental Engineering, Chongqing University, Chongqing 400020 (China); Guo, JinSong [Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400045 (China); Cheng, Jin [Faculty of Urban Construction and Environmental Engineering, Chongqing University, Chongqing 400020 (China)

    2015-07-15

    Highlights: • DOM fractions spectra analysis during the whole treatment process. • Efficient method was achieved to remove organic matters in landfill leachate. • Molecular weight distribution and fractions were discussed. - Abstract: A combined treatment process of air stripping + Fenton + sequencing batch reactor (SBR)+ coagulation was performed to remove the pollutants in landfill leachate. Molecular weight (MW) distribution and fractions of dissolved organic matter (DOM) were discussed to study the characteristics. The experiment showed that the removal rate of chemical oxygen demand (COD), five day biological oxygen demand (BOD{sub 5}) and ammonia nitrogen (NH{sub 3}−N) by the combined process were 92.8%, 87.8% and 98.0%, respectively. Humic acid (HA) and fulvic acid (FA) were the main fractions in raw leachate with 81.8% of the total COD concentration, while hydrophilic organic matter (HyI) was the dominant fraction in the final effluent of the combined process with 63.5% of the total COD concentration. After the combined treatment process, the removal rate of DOM and fractions HA, FA, HyI were 91.9%, 97.1%, 95.8% and 71.7%, respectively. Organic matters of MW < 2 k and MW > 100 k were removed with 90.5% and 97.9% COD concentration after the treatment. The ultraviolet–visible spectra (UV–vis), Fourier transform infrared spectra (FTIR) and three-dimensional excitation-emission matrices spectra (EEMs) indicated that benzene materials and phenol compounds were preferentially removed in air stripping. High MW matters, aromatic rings, conjugated moieties and some functional groups were mainly removed by Fenton. While small MW fractions, carboxylic acids, alcohols and protein-like materials were preferentially biodegraded via SBR. Fulvic-like and humic-like materials were mainly destroyed via Fenton oxidation and coagulation.

  17. Procedures for addressing uncertainty and variability in exposure to characterize potential health risk from trichloroethylene contaminated ground water at Beale Air Force Base in California; TOPICAL

    International Nuclear Information System (INIS)

    Conservative deterministic, screening-level calculations of exposure and risk commonly are used in quantitative assessments of potential human-health consequences from contaminants in environmental media. However, these calculations generally are based on multiple upper-bound point estimates of input parameters, particularly for exposure attributes, and can therefore produce results for decision makers that actually overstate the need for costly remediation. Alternatively, a more informative and quantitative characterization of health risk can be obtained by quantifying uncertainty and variability in exposure. This process is illustrated in this report for a hypothetical population at a specific site at Beale Air Force Base in California, where there is trichloroethylene (TCE) contaminated ground water and a potential for future residential use. When uncertainty and variability in exposure were addressed jointly for this case, the 95th-percentile upper-bound value of individual excess lifetime cancer risk was a factor approaching 10 lower than the most conservative deterministic estimate. Additionally, the probability of more than zero additional cases of cancer can be estimated, and in this case it is less than 0.5 for a hypothetical future residential population of up to 26,900 individuals present for any 7.6-y interval of a 70-y time period. Clearly, the results from application of this probabilistic approach can provide reasonable and equitable risk-acceptability criteria for a contaminated site

  18. [Environmental investigation of ground water contamination at Wright-Patterson Air Force Base, Ohio]. Volume 3, Sampling and analysis plan (SAP): Phase 1, Task 4, Field Investigation: Draft

    Energy Technology Data Exchange (ETDEWEB)

    1991-10-01

    In April 1990, Wright-Patterson Air Force Base (WPAFB), initiated an investigation to evaluate a potential Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) removal action to prevent, to the extent practicable, the offsite migration of contaminated ground water from WPAFB. WPAFB retained the services of the Environmental Management Operations (EMO) and its principle subcontractor, International Technology Corporation (IT) to complete Phase 1 of the environmental investigation of ground-water contamination at WPAFB. Phase 1 of the investigation involves the short-term evaluation and potential design for a program to remove ground-water contamination that appears to be migrating across the western boundary of Area C, and across the northern boundary of Area B along Springfield Pike. Primarily, Task 4 of Phase 1 focuses on collection of information at the Area C and Springfield Pike boundaries of WPAFB. This Sampling and Analysis Plan (SAP) has been prepared to assist in completion of the Task 4 field investigation and is comprised of the Quality Assurance Project Plan (QAPP) and the Field Sampling Plan (FSP).

  19. Procedures for addressing uncertainty and variability in exposure to characterize potential health risk from trichloroethylene contaminated ground water at Beale Air Force Base in California

    Energy Technology Data Exchange (ETDEWEB)

    Daniels, J I; Bogen, K T; Hall, L C

    1999-10-05

    Conservative deterministic, screening-level calculations of exposure and risk commonly are used in quantitative assessments of potential human-health consequences from contaminants in environmental media. However, these calculations generally are based on multiple upper-bound point estimates of input parameters, particularly for exposure attributes, and can therefore produce results for decision makers that actually overstate the need for costly remediation. Alternatively, a more informative and quantitative characterization of health risk can be obtained by quantifying uncertainty and variability in exposure. This process is illustrated in this report for a hypothetical population at a specific site at Beale Air Force Base in California, where there is trichloroethylene (TCE) contaminated ground water and a potential for future residential use. When uncertainty and variability in exposure were addressed jointly for this case, the 95th-percentile upper-bound value of individual excess lifetime cancer risk was a factor approaching 10 lower than the most conservative deterministic estimate. Additionally, the probability of more than zero additional cases of cancer can be estimated, and in this case it is less than 0.5 for a hypothetical future residential population of up to 26,900 individuals present for any 7.6-y interval of a 70-y time period. Clearly, the results from application of this probabilistic approach can provide reasonable and equitable risk-acceptability criteria for a contaminated site.

  20. Effects of warming on uptake and translocation of cadmium (Cd) and copper (Cu) in a contaminated soil-rice system under Free Air Temperature Increase (FATI).

    Science.gov (United States)

    Ge, Li-Qiang; Cang, Long; Liu, Hui; Zhou, Dong-Mei

    2016-07-01

    Global warming has received growing attentions about its potential threats to human in recent, however little is known about its effects on transfer of heavy metals in agro-ecosystem, especially for Cd in rice. Pot experiments were conducted to evaluate Cd/Cu translocation in a contaminated soil-rice system under Free Air Temperature Increase (FATI). The results showed that warming gradually decreased soil porewater pH and increased water-soluble Cd/Cu concentration, reduced formation of iron plaque on root surface, and thus significantly increased total uptake of Cd/Cu by rice. Subsequently, warming significantly promoted Cd translocation from root to shoot, and increased Cd distribution percentage in shoot, while Cu was not significantly affected. Enhanced Cd uptake and translocation synergistically resulted in higher rice grain contamination with increasing concentration from 0.27 to 0.65 and 0.14-0.40 mg kg(-1) for Indica and Japonica rice, respectively. However increase of Cu in brown grain was only attributed to its uptake enhancement under warming. Our study provides a new understanding about the food production insecurity of heavy metal contaminated soil under the future global warming. PMID:27093634

  1. Increasing reliability of gas-air systems of piston and combined internal combustion engines by improving thermal and mechanic flow characteristics

    Science.gov (United States)

    Brodov, Yu. M.; Grigor'ev, N. I.; Zhilkin, B. P.; Plotnikov, L. V.; Shestakov, D. S.

    2015-12-01

    Results of experimental study of thermal and mechanical characteristics of gas exchange flow in piston and combined engines are presented. Ways for improving intake and exhaust processes to increase reliability of gas-air engine systems are proposed.

  2. ON THE RELATIONSHIP BETWEEN AMBIENT DOSE EQUIVALENT AND ABSORBED DOSE IN AIR IN THE CASE OF LARGE-SCALE CONTAMINATION OF THE ENVIRONMENT BY RADIOACTIVE CESIUM

    Directory of Open Access Journals (Sweden)

    V. P. Ramzaev

    2015-01-01

    Full Text Available One of the main aims of the study was an experimental determination of the conversion coefficient from ambient dose equivalent rate, Н*(10, to absorbed dose rate in air, D, in the case of radioactive contamination of the environment following the Chernobyl accident. More than 800 measurements of gamma-dose rates in air were performed at the typical locations (one-storey residential house, street, yard, kitchen-garden, ploughed field, undisturbed grassland, forest of rural settlements and their surroundings in the heavily contaminated areas of the Bryansk region, Russia in the period of 1996–2010. Five commercially available models of portable gamma-ray dosimeters were employed in the investigation. All tested dosimeters were included into the State register of approved measuring instruments of Russia. In all dosimeters, scintillation detectors are used as detection elements. A photon spectrometry technique is applied in the dosimeters to determine gamma dose rate in air. The dosimeters are calibrated in terms of exposure rate, X, absorbed dose rate in air, D, and ambient dose equivalent rate, Н*(10. A very good agreement was found between different dosimeters calibrated in the same units; the reading ratios were close to 1 and the correlation coefficients (Pearson’s or Spearman’s were higher than 0.99. The Н*(10/D ratio values were location-specific ranging from 1.23 Sv/Gy for undisturbed grasslands and forests to 1.47 Sv/Gy for wooden houses and asphalted streets. A statistically significant negative correlation (Spearman’s coefficient = -0.833; P<0.01; n=9 was found between the Н*(10/D ratio and the average energy of gamma-rays determined with a NaI(Tl-based gamma-ray monitor. For the whole area of a settlement and its surroundings, the average ratio of Н*(10 to D was calculated as 1.33 Sv/Gy. The overall conversion coefficient from ambient dose equivalent rate, Н*(10, to external effective dose rate, Ė, for adults was estimated

  3. Performance analysis of a bio-gasification based combined cycle power plant employing indirectly heated humid air turbine

    Science.gov (United States)

    Mukherjee, S.; Mondal, P.; Ghosh, S.

    2016-07-01

    Rapid depletion of fossil fuel has forced mankind to look into alternative fuel resources. In this context, biomass based power generation employing gas turbine appears to be a popular choice. Bio-gasification based combined cycle provides a feasible solution as far as grid-independent power generation is concerned for rural electrification projects. Indirectly heated gas turbine cycles are promising alternatives as they avoid downstream gas cleaning systems. Advanced thermodynamic cycles have become an interesting area of study to improve plant efficiency. Water injected system is one of the most attractive options in this field of applications. This paper presents a theoretical model of a biomass gasification based combined cycle that employs an indirectly heated humid air turbine (HAT) in the topping cycle. Maximum overall electrical efficiency is found to be around 41%. Gas turbine specific air consumption by mass is minimum when pressure ratio is 6. The study reveals that, incorporation of the humidification process helps to improve the overall performance of the plant.

  4. Effect of Gas/Steam Turbine Inlet Temperatures on Combined Cycle Having Air Transpiration Cooled Gas Turbine

    Science.gov (United States)

    Kumar, S.; Singh, O.

    2012-10-01

    Worldwide efforts are being made for further improving the gas/steam combined cycle performance by having better blade cooling technology in topping cycle and enhanced heat recovery in bottoming cycle. The scope of improvement is possible through turbines having higher turbine inlet temperatures (TITs) of both gas turbine and steam turbine. Literature review shows that a combined cycle with transpiration cooled gas turbine has not been analyzed with varying gas/steam TITs. In view of above the present study has been undertaken for thermodynamic study of gas/steam combined cycle with respect to variation in TIT in both topping and bottoming cycles, for air transpiration cooled gas turbine. The performance of combined cycle with dual pressure heat recovery steam generator has been evaluated for different cycle pressure ratios (CPRs) varying from 11 to 23 and the selection diagrams presented for TIT varying from 1,600 to 1,900 K. Both the cycle efficiency and specific work increase with TIT for each pressure ratio. For each TIT there exists an optimum pressure ratio for cycle efficiency and specific work. For the CPR of 23 the best cycle performance is seen at a TIT of 1,900 K for maximum steam temperature of 570 °C, which gives the cycle efficiency of 60.9 % with net specific work of 909 kJ/kg.

  5. Urban atmospheric contamination

    International Nuclear Information System (INIS)

    The problems of contamination are not only limited to this century, pale pathology evidences of the effects of the contamination of the air exist in interiors in the health of the old ones; the article mention the elements that configure the problem of the atmospheric contamination, atmospheric pollutants and emission sources, orography condition and effects induced by the urbanization process

  6. Kentucky Department for Natural Resources and Environmental Protection permit application for air contaminant source: SRC-I demonstration plant, Newman, Kentucky. [Demonstration plant at Newman, KY

    Energy Technology Data Exchange (ETDEWEB)

    None

    1980-11-21

    This document and its several appendices constitute an application for a Kentucky Permit to Construct an Air Contaminant Source as well as a Prevention of Significant Air Quality Deterioration (PSD) Permit Application. The information needed to satisfy the application requirements for both permits has been integrated into a complete and logical description of the proposed source, its emissions, control systems, and its expected air quality impacts. The Department of Energy believes that it has made every reasonable effort to be responsive to both the letter and the spirit of the PSD regulations (40 CFR 52.21) and Kentucky Regulation No. 401 KAR 50:035. In this regard, it is important to note that because of the preliminary status of some aspects of the process engineering and engineering design for the Demonstration Plant, it is not yet possible precisely to define some venting operations or their associated control systems. Therefore, it is not possible precisely to quantify some atmospheric emissions or their likely impact on air quality. In these instances, DOE and ICRC have used assumptions that produce impact estimates that are believed to be worst case and are not expected to be exceeded no matter what the outcome of future engineering decisions. As these decisions are made, emission quantities and rates, control system characteristics and efficiencies, and vent stack parameters are more precisely defined; this Permit Application will be supplemented or modified as appropriate. But, all needed modifications are expected to represent either decreases or at worst no changes in the air quality impact of the SRC-I Demonstration Plant.

  7. Atomic oxygen dynamics in an air dielectric barrier discharge: a combined diagnostic and modeling approach

    Science.gov (United States)

    Baldus, Sabrina; Schröder, Daniel; Bibinov, Nikita; Schulz-von der Gathen, Volker; Awakowicz, Peter

    2015-06-01

    Cold atmospheric pressure plasmas are a promising alternative therapy for treatment of chronic wounds, as they have already shown in clinical trials. In this study an air dielectric barrier discharge (DBD) developed for therapeutic use in dermatology is characterized with respect to the plasma produced reactive oxygen species, namely atomic oxygen and ozone, which are known to be of great importance to wound healing. To understand the plasma chemistry of the applied DBD, xenon-calibrated two-photon laser-induced fluorescence spectroscopy and optical absorption spectroscopy are applied. The measured spatial distributions are shown and compared to each other. A model of the afterglow chemistry based on optical emission spectroscopy is developed to cross-check the measurement results and obtain insight into the dynamics of the considered reactive oxygen species. The atomic oxygen density is found to be located mostly between the electrodes with a maximum density of {{n}\\text{O}}=6× {{10}16} cm-3 . Time resolved measurements reveal a constant atomic oxygen density between two high voltage pulses. The ozone is measured up to 3 mm outside the active plasma volume, reaching a maximum value of {{n}{{\\text{O}3}}}=3× {{10}16} cm-3 between the electrodes.

  8. Algorithm and simulation development in support of response strategies for contamination events in air and water systems.

    Energy Technology Data Exchange (ETDEWEB)

    Waanders, Bart Van Bloemen

    2006-01-01

    Chemical/Biological/Radiological (CBR) contamination events pose a considerable threat to our nation's infrastructure, especially in large internal facilities, external flows, and water distribution systems. Because physical security can only be enforced to a limited degree, deployment of early warning systems is being considered. However to achieve reliable and efficient functionality, several complex questions must be answered: (1) where should sensors be placed, (2) how can sparse sensor information be efficiently used to determine the location of the original intrusion, (3) what are the model and data uncertainties, (4) how should these uncertainties be handled, and (5) how can our algorithms and forward simulations be sufficiently improved to achieve real time performance? This report presents the results of a three year algorithmic and application development to support the identification, mitigation, and risk assessment of CBR contamination events. The main thrust of this investigation was to develop (1) computationally efficient algorithms for strategically placing sensors, (2) identification process of contamination events by using sparse observations, (3) characterization of uncertainty through developing accurate demands forecasts and through investigating uncertain simulation model parameters, (4) risk assessment capabilities, and (5) reduced order modeling methods. The development effort was focused on water distribution systems, large internal facilities, and outdoor areas.

  9. Numerical Simulation of Inter-Flat Air Cross-Contamination under the Condition of Single-Sided Natural Ventilation

    DEFF Research Database (Denmark)

    Liu, Xiaoping; Niu, Jianlei; Perino, Marco;

    2008-01-01

    the two sides, each of which has a flat fa ade with openable windows. When the wind speed is extremely low, with doors closed and windows opened, the flats become single-sided naturally ventilated driven by buoyancy effects. The air pollutants can travel from a lower flat to a vertically adjacent...... upper flat through open windows, caused by indoor/outdoor temperature-difference induced buoyancy. Computational fluid dynamics is employed to explore the characteristics of this process. Based on the comparison with experimental data about the air flow distribution in and around a single...

  10. Abiotic reductive extraction of arsenic from contaminated soils enhanced by complexation: Arsenic extraction by reducing agents and combination of reducing and chelating agents

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Eun Jung [Department of Bioactive Material Sciences, Chonbuk National University, 567 Baekje-daero, Deokjin-gu, Jeonju, Jeollabukdo 561-675 (Korea, Republic of); Lee, Jae-Cheol [Department of Environmental Engineering, Chonbuk National University, 567 Baekje-daero, Deokjin-gu, Jeonju, Jeollabukdo 561-675 (Korea, Republic of); Baek, Kitae, E-mail: kbaek@jbnu.ac.kr [Department of Bioactive Material Sciences, Chonbuk National University, 567 Baekje-daero, Deokjin-gu, Jeonju, Jeollabukdo 561-675 (Korea, Republic of); Department of Environmental Engineering, Chonbuk National University, 567 Baekje-daero, Deokjin-gu, Jeonju, Jeollabukdo 561-675 (Korea, Republic of)

    2015-02-11

    Highlights: • Abiotic reductive extraction of As from contaminated soils was studied. • Oxalate/ascorbate were effective in extracting As bound to amorphous iron oxides. • Reducing agents were not effective in extracting As bound to crystalline oxides. • Reductive As extraction was greatly enhanced by complexation. • Combination of dithionite and EDTA could extract about 90% of the total As. - Abstract: Abiotic reductive extraction of arsenic from contaminated soils was studied with various reducing agents and combinations of reducing and chelating agents in order to remediate arsenic-contaminated soils. Oxalate and ascorbic acid were effective to extract arsenic from soil in which arsenic was associated with amorphous iron oxides, but they were not effective to extract arsenic from soils in which arsenic was bound to crystalline oxides or those in which arsenic was mainly present as a scorodite phase. An X-ray photoelectron spectroscopy study showed that iron oxides present in soils were transformed to Fe(II,III) or Fe(II) oxide forms such as magnetite (Fe{sub 3}O{sub 4}, Fe{sup II}Fe{sub 2}{sup III}O{sub 4}) by reduction with dithionite. Thus, arsenic extraction by dithionite was not effective due to the re-adsorption of arsenic to the newly formed iron oxide phase. Combination of chelating agents with reducing agents greatly improved arsenic extraction from soil samples. About 90% of the total arsenic could be extracted from all soil samples by using a combination of dithionite and EDTA. Chelating agents form strong complexation with iron, which can prevent precipitation of a new iron oxide phase and also enhance iron oxide dissolution via a non-reductive dissolution pathway.

  11. Combination of synoptical-analogous and dynamical methods to increase skill score of monthly air temperature forecasts over Northern Eurasia

    Science.gov (United States)

    Khan, Valentina; Tscepelev, Valery; Vilfand, Roman; Kulikova, Irina; Kruglova, Ekaterina; Tischenko, Vladimir

    2016-04-01

    Long-range forecasts at monthly-seasonal time scale are in great demand of socio-economic sectors for exploiting climate-related risks and opportunities. At the same time, the quality of long-range forecasts is not fully responding to user application necessities. Different approaches, including combination of different prognostic models, are used in forecast centers to increase the prediction skill for specific regions and globally. In the present study, two forecasting methods are considered which are exploited in operational practice of Hydrometeorological Center of Russia. One of them is synoptical-analogous method of forecasting of surface air temperature at monthly scale. Another one is dynamical system based on the global semi-Lagrangian model SL-AV, developed in collaboration of Institute of Numerical Mathematics and Hydrometeorological Centre of Russia. The seasonal version of this model has been used to issue global and regional forecasts at monthly-seasonal time scales. This study presents results of the evaluation of surface air temperature forecasts generated with using above mentioned synoptical-statistical and dynamical models, and their combination to potentially increase skill score over Northern Eurasia. The test sample of operational forecasts is encompassing period from 2010 through 2015. The seasonal and interannual variability of skill scores of these methods has been discussed. It was noticed that the quality of all forecasts is highly dependent on the inertia of macro-circulation processes. The skill scores of forecasts are decreasing during significant alterations of synoptical fields for both dynamical and empirical schemes. Procedure of combination of forecasts from different methods, in some cases, has demonstrated its effectiveness. For this study the support has been provided by Grant of Russian Science Foundation (№14-37-00053).

  12. LOCAL AIR: Local Aerosol monitoring combining in-situ and Remote Sensing observations

    Science.gov (United States)

    Mona, Lucia; Caggiano, Rosa; Donvito, Angelo; Giannini, Vincenzo; Papagiannopoulos, Nikolaos; Sarli, Valentina; Trippetta, Serena

    2015-04-01

    local sources, which in the troposphere, where there are aerosols transported over long distances by the phenomena of atmospheric circulation. The purpose of the LOCAL AIR project is the development of a methodology for using synergistic data at different resolutions (ground measurements, remote sensing from ground and satellite) as an effective tool for the characterization of tropospheric aerosols on a local scale. The backbone of the project is the long-term ground-based measurements collected at CIAO (CNR-IMAA Atmospheric Observatory) plus the CALIPSO observations.. The location of the plethora of instruments and measurements of atmospheric interest available at CNR-IMAA makes it a sample site not only for the realization of the methodology, but also allows a feasibility study of this method in the absence of some by analysis of the measures considered in the scaling down of the algorithm developed. It will be evaluated the applicability and reliability of the algorithm implemented for the characterization of the aerosol content to the ground in other places of special interest. Acknowledgments: LOCAL AIR is supported by PO FSE Basilicata 2007-2013 Azione n. 45/AP/05/2013/REG - CUP: G53G13000300009.

  13. Development of open air silicon deposition technology by silane-free atmospheric pressure plasma enhanced chemical transport under local ambient gas control

    Science.gov (United States)

    Naito, Teruki; Konno, Nobuaki; Yoshida, Yukihisa

    2016-07-01

    Open air silicon deposition was performed by combining silane-free atmospheric pressure plasma-enhanced chemical transport and a newly developed local ambient gas control technology. The effect of air contamination on silicon deposition was investigated using a vacuum chamber, and the allowable air contamination level was confirmed to be 3 ppm. The capability of the local ambient gas control head was investigated numerically and experimentally. A safe and clean process environment with air contamination less than 1 ppm was achieved. Combining these technologies, a microcrystalline silicon film was deposited in open air, the properties of which were comparable to those of silicon films deposited in a vacuum chamber.

  14. Destruction of benzene in an air stream by the outer combined plasma photolysis method

    International Nuclear Information System (INIS)

    An outer combined plasma photolysis (OCPP) reactor that simultaneously utilized a dielectric barrier discharge (DBD) plasma and UV radiation from DBD-driven KrI* excimer was designed and constructed. Gas streams containing benzene were treated with normal DBD and OCPP at atmospheric pressure. In contrast to DBD, benzene removal efficiency increased by 15.9% in OCPP when applied voltage, gas flow rate and initial concentration of benzene were set at 9 kV, 35 L min-1 and 800 mg m-3, respectively. Thus, the applied voltage could be reduced to a certain extent in the plasma decomposition of pollutants with OCPP. In addition, the effects of various operational parameters including pressure of filled Kr, ratio of Kr/I2 and quartz dielectric characteristics on OCPP performance were investigated. Finally, the likely reaction mechanisms for the removal of benzene by OCPP were suggested on the basis of the emission spectra of KrI* excimer and byproducts analysis. Those results would offer prospective commercial applications for pollutant decomposition with OCPP

  15. Destruction of benzene in an air stream by the outer combined plasma photolysis method

    Science.gov (United States)

    Lian Ye, Zhao; Shen, Yan; Zhang Xi, Ren; Hou, Hui Qi

    2008-01-01

    An outer combined plasma photolysis (OCPP) reactor that simultaneously utilized a dielectric barrier discharge (DBD) plasma and UV radiation from DBD-driven KrI* excimer was designed and constructed. Gas streams containing benzene were treated with normal DBD and OCPP at atmospheric pressure. In contrast to DBD, benzene removal efficiency increased by 15.9% in OCPP when applied voltage, gas flow rate and initial concentration of benzene were set at 9 kV, 35 L min-1 and 800 mg m-3, respectively. Thus, the applied voltage could be reduced to a certain extent in the plasma decomposition of pollutants with OCPP. In addition, the effects of various operational parameters including pressure of filled Kr, ratio of Kr/I2 and quartz dielectric characteristics on OCPP performance were investigated. Finally, the likely reaction mechanisms for the removal of benzene by OCPP were suggested on the basis of the emission spectra of KrI* excimer and byproducts analysis. Those results would offer prospective commercial applications for pollutant decomposition with OCPP.

  16. Decorporation approach following rat lung contamination with a moderately soluble compound of plutonium using local and systemic Ca-DTPA combined chelation

    International Nuclear Information System (INIS)

    Decorporation efficacy of prompt pulmonary delivery of DTPA dry powder was assessed following lung contamination with plutonium nitrate and compared to an intravenous injection of DTPA solution and a combined administration of both DTPA compounds. In addition, efficacy of a delayed treatment was assessed. In case of either early or late administration, insufflated DTPA was more efficient than intravenously injected DTPA in reducing the plutonium lung burden due to its high local concentration. Prompt treatment with DTPA powder was also more effective in limiting extrapulmonary deposits by removing the early transportable fraction of plutonium from lungs prior its absorption into blood. Translocation of DTPA from lungs to blood may also contribute to the decrease in extrapulmonary retention, as shown by reduced liver deposit after delayed pulmonary administration of DTPA. Efficacy of DTPA dry powder was further increased by the combined intravenous administration of DTPA solution for reducing extrapulmonary deposits of plutonium and promoting its urinary excretion. According to our results, the most effective treatment protocol for plutonium decorporation was the early pulmonary delivery of DTPA powder supplemented by an intravenous injection of DTPA solution. Following inhalation of plutonium as nitrate chemical form, this combined chelation therapy should provide a more effective method of treatment than conventional intravenous injection alone. At later stages following lung contamination, pulmonary administration of DTPA should also be considered as the treatment of choice for decreasing the lung burden. (authors)

  17. Effect of alkyl polyglucoside and nitrilotriacetic acid combined application on lead/pyrene bioavailability and dehydrogenase activity in co-contaminated soils.

    Science.gov (United States)

    Chen, Tingru; Liu, Xiaoyan; Zhang, Xinying; Chen, Xiao; Tao, Kaiyun; Hu, Xiaoxin

    2016-07-01

    At present, few research focus on the phytoremediation for organic pollutants and heavy metals enhanced by surfactants and chelate agents in the combined contaminated soils or sediments. In this study, the effect of a novel combined addition of alkyl polyglucoside (APG) and nitrilotriacetic acid (NTA) into pyrene and lead (Pb) co-contaminated soils on bioaccessiblity of pyrene/Pb and dehydrogenase activities (DHA) was studied. Through the comparison of the results with the alone and combined application, synergistic effect on bioaccessiblity of pyrene and Pb was found while APG and NTA was applied together. Results also indicated a significant promotion on the DHA in mixed addition of APG and NTA. In addition, correlation and principal component analysis were performed to better understand the relationship among APG/NTA, bioaccessiblity of pyrene/Pb and the DHA. Results showed that APG and NTA can affect DHA directly by themselves but also can affect DHA indirectly by changing bioaccessible pyrene and exchangeable Pb. PMID:27085066

  18. Comparison of arterial and venous blood gases and the effects of analysis delay and air contamination on arterial samples in patients with chronic obstructive pulmonary disease and healthy controls.

    LENUS (Irish Health Repository)

    O'Connor, T M

    2012-01-31

    BACKGROUND: Arterial blood gases (ABGs) are often sampled incorrectly, leading to a \\'mixed\\' or venous sample. Delays in analysis and air contamination are common. OBJECTIVES: We measured the effects of these errors in patients with chronic obstructive pulmonary disease (COPD) exacerbations and controls. METHODS: Arterial and venous samples were analyzed from 30 patients with COPD exacerbation and 30 controls. Venous samples were analysed immediately and arterial samples separated into non-air-contaminated and air-contaminated specimens and analysed at 0, 30, 60, 90 and 180 min. RESULTS: Mean venous pH was 7.371 and arterial pH was 7.407 (p < 0.0001). There was a correlation between venous and arterial pH (r = 0.5347, p < 0.0001). The regression equation to predict arterial pH was: arterial pH = 4.2289 + 0.43113 . venous pH. There were no clinically significant differences in arterial PO associated with analysis delay. A statistically significant decline in pH was detected at 30 min in patients with COPD exacerbation (p = 0.0042) and 90 min in controls (p < 0.0001). A clinically significant decline in pH emerged at 73 min in patients with COPD exacerbation and 87 min in controls. Air contamination was associated with a clinically significant increase in PO in all samples, including those that were immediately analyzed. CONCLUSIONS: Arterial and venous pH differ significantly. Venous pH cannot accurately replace arterial pH. Temporal delays in ABG analysis result in a significant decline in measured pH. ABGs should be analysed within 30 min. Air contamination leads to an immediate increase in measured PO, indicating that air-contaminated ABGs should be discarded.

  19. Monitoring air sparging using resistivity tomography

    International Nuclear Information System (INIS)

    Air sparging is a relatively new technique for the remediation of ground water contaminated with petroleum hydrocarbons. In this technique, air is injected below the water table, beneath the contaminated soil. Remediation occurs by a combination of contaminant partitioning into the vapor phase and enhanced biodegradation. The air is usually removed by vacuum extraction in the vadose zone. The efficiency of remediation from air sparging is a function of the air flow pattern, although the distribution of the injected air is still poorly understood. Cross-borehole resistivity surveys were performed at a former service station in Florence, Oregon, to address this unknown. The resistivity measurements were made using six wells, one of which was the sparge well. Data were collected over a two-week period during and after several air injections, or sparge events. Resistivity images were calculated between wells using an algorithm that assumes axially symmetric structures. The movement of the injected air through time was defined by regions of large increases in resistivity, greater than 100 percent from the background. During early sparge times, air moved outward and upward from the injection point as it ascended to the unsaturated zone. At later sparge times, the air flow reached a somewhat stable cone-shaped pattern radiating out and up from the injection point. Two days after sparging was discontinued, a residue of entrained air remained in the saturated zone, as indicated by a zone of 60 to 80 percent water saturation

  20. Comparison of Near-field and Far-field Air Monitoring of Plutonium-contaminated Soils from the Tonopah Test Range, Nevada

    Energy Technology Data Exchange (ETDEWEB)

    John L. Bowen; David S. Shafer

    2001-05-01

    Operation Roller Coaster, a series of nuclear material dispersal experiments, resulted in three areas (Clean Slates 1, 2, and 3) of widespread surface soil plutonium (Pu) contamination on the Tonopah Test Range (TTR), located 225 miles northwest of Las Vegas, Nevada. The State's Division of Environmental Protection raised concerns that dispersal of airborne Pu particles from the sites could result in undetected deposition further downwind that the background monitoring stations. Air monitoring data from different distances from the Clean Slate sites but during the same period of time were compared. From the available data, there is no indication that airborne PM10 particles are being transported to the farther distance,however, the data are statistically insufficient to conclude whether there is a difference in transport of respirable Pu particles to the closer verses the farther sites from the Clean Slate sites.

  1. Nuclear and Physical Methods of Control For soil and Near-ground Air Contamination With Plutonium and Americium-241 in Belarus

    International Nuclear Information System (INIS)

    As a result of the Chernobyl NPP accident considerable territories of Belarus have been contaminated with Pu and 241Am. The absence of instrumental techniques for a direct analysis of transuranium elements (TUE) in the objects of the environment has made the using of laborious radiochemical methods inevitable what, in its turn, has limited a necessary scale of investigations on TUE problem. The paper presents the more cheap and express instrumental nuclear and physical techniques for Pu and 241Am analysis in soils and near-ground layer of air having been developed at the Institute of Power Engineering Problems / National Academy of Sciences of Belarus (IPEP NASB), as well as some results having been obtained using these techniques

  2. Forest fires in Eastern countries: air contamination measurements by the IRSN. Information file; Incendies de forets dans les pays de l'Est: mesures de la contamination de l'air par l'IRSN. Fiche d'information

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-07-01

    Forest fires sparking of in contaminated territories of Bielorussia, Ukraine and Western Russia can lead to transfrontier contamination in particular in Western Europe. Such radiological events with {sup 137}Cs peaks were recorded in France in 2002 (weeks 35 and 37) by the OPERA-Air network of the French Institute of Radiation Protection and Nuclear Safety (IRSN). These rises of {sup 137}Cs activity can be recorded only when France is under the influence of winds coming from the E-NE. The activity levels of such events is of the order of maximum 1.5 {mu}Bq/m{sup 3} and cannot represent any threat for the populations' health. (J.S.)

  3. Combined steam-ultrasound treatment of 2 seconds achieves significant high aerobic count and Enterobacteriaceae reduction on naturally contaminated food boxes, crates, conveyor belts, and meat knives.

    Science.gov (United States)

    Musavian, Hanieh S; Butt, Tariq M; Larsen, Annette Baltzer; Krebs, Niels

    2015-02-01

    Food contact surfaces require rigorous sanitation procedures for decontamination, although these methods very often fail to efficiently clean and disinfect surfaces that are visibly contaminated with food residues and possible biofilms. In this study, the results of a short treatment (1 to 2 s) of combined steam (95°C) and ultrasound (SonoSteam) of industrial fish and meat transportation boxes and live-chicken transportation crates naturally contaminated with food and fecal residues were investigated. Aerobic counts of 5.0 to 6.0 log CFU/24 cm(2) and an Enterobacteriaceae spp. level of 2.0 CFU/24 cm(2) were found on the surfaces prior to the treatment. After 1 s of treatment, the aerobic counts were significantly (P plastic modular conveyor belts with hinge pins and one type of flat flexible rubber belt, all visibly contaminated with food residues. The aerobic counts of 3.0 to 5.0 CFU/50 cm(2) were significantly (P effective replacement for disinfection processes and that it can be used for continuous disinfection at fast process lines. However, the treatment may not be able to replace efficient cleaning processes used to remove high loads of debris. PMID:25710163

  4. Possibility of using combined treatment of processing and ionizing radiation to eliminate contaminated viruses from non-screened donor of tissue allografts

    International Nuclear Information System (INIS)

    Full text: New emerging and re- emerging infectious diseases caused by viruses are outbreak and re- outbreak around the world. Most of the viruses come from animals ( zoonoses) and jump to human beings ( host jumping ) such as corona virus ( SARS), HIV, bird flu/ Avian flu H5N1, hepatitis viruses, Dengue fever virus, West Nile virus/WNV, Hantavirus, Marburg haemorrhagic fever virus, Hendra virus, Nipah virus etc. Transmission of those diseases through transplantation of contaminated tissue allograft to recipient can happened if the donor could not be screened properly. The donor can be well screened from some of those viruses such as HIV, hepatitis viruses and WNV. Processing of tissue allografts by pasteurization, washing and soaking in H2O2 and soap can eliminate contaminated viruses to a certain amount, have been reported by several authors. Viruses are very small microbes, they have DNA/RNA, resistant to radiation but to a certain degree they can be well eliminated by radiation. Their D10 - values vary from 4 to 13 kGy. This paper discribes briefly the possibility of using combined treatment of processing, lyophilization and sterilisation by radiation to overcome problems of non screened donor from some contaminated viruses. (Author)

  5. [Environmental investigation of ground water contamination at Wright-Patterson Air Force Base, Ohio]. Volume 2, Work plan: Phase 1, Task 4, Field Investigation: Draft

    Energy Technology Data Exchange (ETDEWEB)

    1991-10-01

    In April 1990 Wright-Patterson Air Force Base (WPAFB) initiated an investigation to evaluate a potential CERCLA removal action to prevent, to the extent practicable, the migration of ground-water contamination in the Mad River Valley Aquifer within and across WPAFB boundaries. The action will be based on a Focused Feasibility Study with an Action Memorandum serving as a decision document that is subject to approval by the Ohio Environmental Protection Agency. The first phase (Phase 1) of this effort involves an investigation of ground-water contamination migrating across the southwest boundary of Area C and across Springfield Pike adjacent to Area B. Task 4 of Phase 1 is a field investigation to collect sufficient additional information to evaluate removal alternatives. The field investigation will provide information in the following specific areas of study: water-level data which will be used to permit calibration of the ground-water flow model to a unique time in history; and ground-water quality data which will be used to characterize the current chemical conditions of ground water.

  6. Occurrence and potential combined toxicity of dissolved organic contaminants in the Forth estuary and Firth of Forth, Scotland assessed using passive samplers and an algal toxicity test.

    Science.gov (United States)

    Emelogu, Emmanuel S; Pollard, Pat; Dymond, Peter; Robinson, Craig D; Webster, Lynda; McKenzie, Craig; Dobson, Judy; Bresnan, Eileen; Moffat, Colin F

    2013-09-01

    As an alternative procedure to conventional water quality assessment, the presence and combined toxicity of dissolved organic contaminants in water at five sites in the Forth estuary and the Firth of Forth, Scotland, United Kingdom was investigated using silicone rubber passive sampling devices (SR-PSDs) and an algal growth inhibition bioassay. SR-PSDs were deployed in water at the five sites for ~2 months. Following retrieval, extracts from the deployed SR-PSDs were assessed for both algal growth inhibition and the occurrence of a wide range of organic contaminants, including polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), and a variety of plant protection products (PPPs; commonly referred to collectively as 'pesticides'). The 72 h algal growth inhibition test was performed using a native marine phytoplankton (Diacronema lutheri) in 24 well microplates. Freely dissolved (e.g. bioavailable) concentrations of PAHs and PCBs were determined using performance reference compounds (PRCs). The algal toxicity tests exhibited varied effects at the five sites indicating the presence of, and exposure to, phytotoxic compounds and their potential toxicity in the Forth. The individual and total dissolved concentrations of 40 PAHs and 32 PCBs measured in the study were relatively low and showed input of petrogenic, atmospheric and sewage related sources. Several pesticides of diverse polarities were identified in the water suggesting sources from both riverine input and direct discharges. The study thus illustrates the value of combining bioassays and chemical analysis (with effective sampling technique) for a realistic and rapid assessment of organic contaminants in the aquatic environment. PMID:23728064

  7. Plant tolerance to mercury in a contaminated soil is enhanced by the combined effects of humic matter addition and inoculation with arbuscular mycorrhizal fungi.

    Science.gov (United States)

    Cozzolino, V; De Martino, A; Nebbioso, A; Di Meo, V; Salluzzo, A; Piccolo, A

    2016-06-01

    In a greenhouse pot experiment, lettuce plants (Lactuca sativa L.) were grown in a Hg-contaminated sandy soil with and without inoculation with arbuscular mycorrhizal fungi (AMF) (a commercial inoculum containing infective propagules of Rhizophagus irregularis and Funneliformis mosseae) amended with different rates of a humic acid (0, 1, and 2 g kg(-1) of soil), with the objective of verifying the synergistic effects of the two soil treatments on the Hg tolerance of lettuce plants. Our results indicated that the plant biomass was significantly increased by the combined effect of AMF and humic acid treatments. Addition of humic matter to soil boosted the AMF effect on improving the nutritional plant status, enhancing the pigment content in plant leaves, and inhibiting both Hg uptake and Hg translocation from the roots to the shoots. This was attributed not only to the Hg immobilization by stable complexes with HA and with extraradical mycorrhizal mycelium in soil and root surfaces but also to an improved mineral nutrition promoted by AMF. This work indicates that the combined use of AMF and humic acids may become a useful practice in Hg-contaminated soils to reduce Hg toxicity to crops. PMID:26931658

  8. Remediation of PAH-contaminated soil at a gas manufacturing plant by a combined two-phase partition system washing and microbial degradation process.

    Science.gov (United States)

    Gong, Xuan; Xu, Xinyang; Gong, Zongqiang; Li, Xiaojun; Jia, Chunyun; Guo, Meixia; Li, Haibo

    2015-08-01

    The aim of this study was to design a remediation technique using both soil washing and microbial degradation to remove polycyclic aromatic hydrocarbons (PAHs) from contaminated soil. PAH biodegradation by inoculation of Mycobacterium sp. was first tested. The effectiveness of washing agents (Tween 80 solution, biodiesel, and a two-phase partition system (TPPS)) was then evaluated with column experiments. Third, the combination of TPPS washing and microbial degradation was studied. PAH bioavailability before and after biodegradation and the joint remediation was also assessed using hydroxypropyl-β-cyclodextrin (HPCD) extraction. Only phenanthrene and anthracene were noticeably biodegradable when the soil was inoculated with Mycobacterium sp. TPPS containing 2% (v/v) biodiesel and 2.5% (w/v) Tween 80 was used as the washing agent for the joint remediation test because it gave higher PAH extractions than Tween 80 solution with lower doses, and there was less residue in the soil. Joint TPPS washing and microbial degradation gave a total PAH removal of 92.6%, which was much higher than the results from either the biodegradation or washing experiments alone. Removals of all high molecular weight (HMW) PAHs were improved. Bioavailable concentrations of all PAHs decreased significantly after the joint remediation process, indicating that there were reduced risks from all PAHs. The results demonstrate that the combination of TPPS washing and microbial degradation is a useful and innovative process for remediation of PAH-contaminated soils. PMID:25874432

  9. Two-Dimensional Algal Collection and Assembly by Combining AC-Dielectrophoresis with Fluorescence Detection for Contaminant-Induced Oxidative Stress Sensing.

    Science.gov (United States)

    Siebman, Coralie; Velev, Orlin D; Slaveykova, Vera I

    2015-06-01

    An alternative current (AC) dielectrophoretic lab-on-chip setup was evaluated as a rapid tool of capture and assembly of microalga Chlamydomonas reinhardtii in two-dimensional (2D) close-packed arrays. An electric field of 100 V·cm⁻¹, 100 Hz applied for 30 min was found optimal to collect and assemble the algae into single-layer structures of closely packed cells without inducing cellular oxidative stress. Combined with oxidative stress specific staining and fluorescence microscopy detection, the capability of using the 2D whole-cell assembly on-chip to follow the reactive oxygen species (ROS) production and oxidative stress during short-term exposure to several environmental contaminants, including mercury, methylmercury, copper, copper oxide nanoparticles (CuO-NPs), and diuron was explored. The results showed significant increase of the cellular ROS when C. reinhardtii was exposed to high concentrations of methylmercury, CuO-NPs, and 10⁻⁵ M Cu. Overall, this study demonstrates the potential of combining AC-dielectrophoretically assembled two-dimensional algal structures with cell metabolic analysis using fluorescence staining, as a rapid analytical tool for probing the effect of contaminants in highly impacted environment. PMID:26083806

  10. Two-Dimensional Algal Collection and Assembly by Combining AC-Dielectrophoresis with Fluorescence Detection for Contaminant-Induced Oxidative Stress Sensing

    Directory of Open Access Journals (Sweden)

    Coralie Siebman

    2015-06-01

    Full Text Available An alternative current (AC dielectrophoretic lab-on-chip setup was evaluated as a rapid tool of capture and assembly of microalga Chlamydomonas reinhardtii in two-dimensional (2D close-packed arrays. An electric field of 100 V·cm−1, 100 Hz applied for 30 min was found optimal to collect and assemble the algae into single-layer structures of closely packed cells without inducing cellular oxidative stress. Combined with oxidative stress specific staining and fluorescence microscopy detection, the capability of using the 2D whole-cell assembly on-chip to follow the reactive oxygen species (ROS production and oxidative stress during short-term exposure to several environmental contaminants, including mercury, methylmercury, copper, copper oxide nanoparticles (CuO-NPs, and diuron was explored. The results showed significant increase of the cellular ROS when C. reinhardtii was exposed to high concentrations of methylmercury, CuO-NPs, and 10−5 M Cu. Overall, this study demonstrates the potential of combining AC-dielectrophoretically assembled two-dimensional algal structures with cell metabolic analysis using fluorescence staining, as a rapid analytical tool for probing the effect of contaminants in highly impacted environment.

  11. Investigation on the kinetic models for the regeneration of silica gel by hot air combined with power ultrasonic

    International Nuclear Information System (INIS)

    Highlights: → We examine five models for the silica gel regeneration assisted by ultrasonic. → The Gaussian and the Weibull model are superior to the others for the modeling. → The Weibull model is recommended for its parameters can be identified more easily. → The validity of the model depends greatly on that of the equilibrium moisture content. - Abstract: Regeneration of dehumidizers (a typical drying process) is the most important stage in the working cycle of desiccant system. Ultrasonic technology, as a non-heating method, can enhance drying kinetics and improve energy utilization efficiency in the drying process. This work has made an investigation on five different drying models, i.e., the Lewis, the Henderson and Pabis, the Logarithmic, the Weibull and the Gaussian model, that quantify the drying kinetics of silica gel during the regeneration by hot air combined with power ultrasonic according to the experimental data. The experiments were performed under different drying air temperatures (i.e. 45 deg. C, 55 deg. C, 65 deg. C and 75 deg. C) plus power ultrasonic with three kinds of frequencies (i.e. 21 kHz, 26 kHz and 38 kHz) and three power levels (20 W, 40 W and 60 W). The models were identified by fitting the experimental data with Matlab's curve fitting tool, and the suitability of these models for predicting the moisture ratio evolution in silica gel during the regeneration was evaluated by the percent error (PE, %). The results showed that the Gaussian and the Weibull model were much more accurate than the other ones in describing the drying kinetics of silica gel assisted by the power ultrasonic. The parameter, β, in the Weibull model, which is like the drying rate constant (K) in the semi-theoretical models (e.g., the Lewis, the Henderson and Pabis and the Logarithmic model), can be found to have a regular relation with the drying temperatures, and hence, will be more convenient for modeling.

  12. Contamination by mercury in air of the mining district of San Martin de Loba in Bolivar's Department, Colombia

    International Nuclear Information System (INIS)

    Mercury (Hg) is a heavy metal, considered a highly toxic pollutant. In its elemental state is volatile, making it easy to transport over long distances through the atmosphere, so that environmental pollution caused by it is a serious problem worldwide. Activities such as gold mining, where metallic Hg is used, have contributed with its global distribution, affecting ecosystems and human health. The aim of this study was to determine the levels of total mercury (T-Hg) in air in gold mining areas in Southern Bolivar, particularly in the mining district of San Martin de Loba, in the municipalities of San Martin de Loba and Barranco de Loba (Mina Santa Cruz), Colombia. In situ analyses were performed by atomic absorption spectroscopy, using a portable Ra-915 + Zeeman mercury analyzer. In Mina Santa Cruz, one of the most important gold mines in Colombia, concentrations of Hg in air ranged between 163.7 ± 6.6 and 40 455 ± 2154 mg/m3, while in the urban area of San Martin de Loba varied from 223.6 ± 20.8 to 27 140 ± 212.5 ng/m3. In those places where an amalgam burning process was taking place at the time of the measurements, Hg concentrations reached values of 40 455 ± 2154 ng/m3. These data imply a severe occupational exposure to Hg for operators and citizens living in cities located near mines. Therefore, it is important to regulate and control the use of Hg in gold mining, avoiding a chronic impact of the metal on the health of people and the environment. (author)

  13. Persistent organic contaminants in Saharan dust air masses in West Africa, Cape Verde and the eastern Caribbean.

    Science.gov (United States)

    Garrison, V H; Majewski, M S; Foreman, W T; Genualdi, S A; Mohammed, A; Massey Simonich, S L

    2014-01-15

    Anthropogenic semivolatile organic compounds (SOCs) that persist in the environment, bioaccumulate, are toxic at low concentrations, and undergo long-range atmospheric transport (LRT) were identified and quantified in the atmosphere of a Saharan dust source region (Mali) and during Saharan dust incursions at downwind sites in the eastern Caribbean (U.S. Virgin Islands, Trinidad and Tobago) and Cape Verde. More organochlorine and organophosphate pesticides (OCPPs), polycyclic aromatic hydrocarbons (PAHs), and polychlorinated biphenyl (PCB) congeners were detected in the Saharan dust region than at downwind sites. Seven of the 13 OCPPs detected occurred at all sites: chlordanes, chlorpyrifos, dacthal, dieldrin, endosulfans, hexachlorobenzene (HCB), and trifluralin. Total SOCs ranged from 1.9-126 ng/m(3) (mean = 25 ± 34) at source and 0.05-0.71 ng/m(3) (mean = 0.24 ± 0.18) at downwind sites during dust conditions. Most SOC concentrations were 1-3 orders of magnitude higher in source than downwind sites. A Saharan source was confirmed for sampled air masses at downwind sites based on dust particle elemental composition and rare earth ratios, atmospheric back trajectory models, and field observations. SOC concentrations were considerably below existing occupational and/or regulatory limits; however, few regulatory limits exist for these persistent organic compounds. Long-term effects of chronic exposure to low concentrations of SOCs are unknown, as are possible additive or synergistic effects of mixtures of SOCs, biologically active trace metals, and mineral dust particles transported together in Saharan dust air masses. PMID:24055669

  14. Nitrogen fixation, denitrification and CO2 flux under condition of combined γ-irradiation and heavy metals contamination in soil

    International Nuclear Information System (INIS)

    In model experiment it was revealed Zn- and Cd-dependent γ-potentizing effect of combined action of γ-radiation and heavy metals on nitrogen fixation, denitrification and CO2 flux in soddy-podzolic soils. 10 refs.; 4 figs

  15. Mapping real-time air pollution health risk for environmental management: Combining mobile and stationary air pollution monitoring with neural network models.

    Science.gov (United States)

    Adams, Matthew D; Kanaroglou, Pavlos S

    2016-03-01

    Air pollution poses health concerns at the global scale. The challenge of managing air pollution is significant because of the many air pollutants, insufficient funds for monitoring and abatement programs, and political and social challenges in defining policy to limit emissions. Some governments provide citizens with air pollution health risk information to allow them to limit their exposure. However, many regions still have insufficient air pollution monitoring networks to provide real-time mapping. Where available, these risk mapping systems either provide absolute concentration data or the concentrations are used to derive an Air Quality Index, which provides the air pollution risk for a mix of air pollutants with a single value. When risk information is presented as a single value for an entire region it does not inform on the spatial variation within the region. Without an understanding of the local variation residents can only make a partially informed decision when choosing daily activities. The single value is typically provided because of a limited number of active monitoring units in the area. In our work, we overcome this issue by leveraging mobile air pollution monitoring techniques, meteorological information and land use information to map real-time air pollution health risks. We propose an approach that can provide improved health risk information to the public by applying neural network models within a framework that is inspired by land use regression. Mobile air pollution monitoring campaigns were conducted across Hamilton from 2005 to 2013. These mobile air pollution data were modelled with a number of predictor variables that included information on the surrounding land use characteristics, the meteorological conditions, air pollution concentrations from fixed location monitors, and traffic information during the time of collection. Fine particulate matter and nitrogen dioxide were both modelled. During the model fitting process we reserved

  16. Soil washing in combination with homogeneous Fenton-like oxidation for the removal of 2,4,4'-trichlorodiphenyl from soil contaminated with capacitor oil.

    Science.gov (United States)

    Ma, Xiao-Hong; Zhao, Ling; Lin, Zhi-Rong; Dong, Yuan-Hua

    2016-04-01

    Detoxification by chemical oxidation of polychlorinated biphenyls (PCBs) in contaminated soils is very difficult and inefficient because PCBs typically associate with the solid phase or exist as non-aqueous-phase liquids due to their low solubility and slow desorption rates, and thus, they are difficult to remove from soils by using traditional, water-based elution techniques. Surfactant can enhance washing efficiency of PCBs from contaminated soils. This study used Brij 58, Brij 30, Tween 80, and 2-hydroxypropyl-β-cyclodextrin (HPCD) to solubilize 2,4,4'-trichlorodiphenyl (PCB28) from soil contaminated with capacitor oil into solution. The feasibility of PCB28 oxidation in soil washing wastewater through a Fe(3+)-catalyzed Fenton-like reaction was subsequently examined. Washing with 10 g L(-1) Brij 58 solution showed the highest extraction efficiency (up to 61.5 %) compared with that of the three other surfactants. The total concentration of PCB28 in contaminated soil at 25 °C after 48-h extraction was 286 mg L(-1). In contrast to conditions in which no washing agent was added, addition of the four washing agents decreased the efficiency of PCB28 degradation by the Fenton-like reaction, with the decrease due to addition of 10 g L(-1) Brij 58 solution being the smallest. The optimal concentration of H2O2 for preventing its useless decomposition was found to be 50 mM. The efficiency of PCB28 removal was lower when the initial concentration of PCB28 treated in the Fenton-like reaction was higher. The degradation efficiencies of PCB28 at initial concentrations of 0.1, 10, and 176 mg L(-1) in 10 g L(-1) Brij 58 solution at 25 °C and pH 3.0 and 9 h of reaction using 50 mM H2O2 were 64.1, 42.0, and 34.6 %, respectively. This result indicates that soil washing combined with Fenton-like oxidation may be a practical approach for the remediation of PCB-contaminated soil. PMID:26762933

  17. Contaminación fecal canina en plazas y veredas de Buenos Aires, 1991-2006 Dog fouling and helminth contamination in parks and sidewalks of Buenos Aires City, 1991-2006

    Directory of Open Access Journals (Sweden)

    Diana Rubel

    2010-08-01

    Full Text Available El objetivo del trabajo fue presentar y analizar los datos de contaminación fecal canina y parasitaria en plazas y veredas de Buenos Aires obtenidos entre 1991 y 2006 por la Cátedra Parasitología General (Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires. Se censaron las heces en varias plazas cada año en un único día entre 1991-2006. A partir del año 2000 se censaron heces en veredas circundantes. En cada plaza se seleccionaron al azar 30 heces frescas que se conservaron en formol 5% para su análisis parasitológico por el método de flotación de Willis con solución saturada de ClNa. Los 51 censos presentaron una mediana de heces de 288; un 82% de las heces se observaron en los canteros de tierra o pasto. La contaminación fecal en las plazas fue mayor en el período 2000-06 que en el anterior (p = 0.0000. La contaminación fecal de las plazas aumentó con la densidad humana en las manzanas lindantes (p = 0.0076. Las veredas mostraron un patrón inverso, ya que la contaminación fecal fue mayor en las áreas menos densamente pobladas (p = 0.0000. Se detectaron parásitos en un número variable de las heces colectadas en todas las plazas. Los géneros más frecuentes fueron Ancylostoma (20.47%, Trichuris (2.59% y Toxocara (1.70%. Nuestros resultados indican un aumento en la contaminación fecal de las plazas, posiblemente asociado con el aumento del número de perros en la ciudad combinado con las deficiencias en la implementación y el seguimiento de las medidas de control.The aim of this study was to provide data on canine fecal and helminthic contamination from parks and sidewalks in Buenos Aires City, collected by the Laboratory of General Parasitology, School of Sciences, University of Buenos Aires. A census of dog feces was performed in 1-11 parks per year between 1991 and 2006, a single day each year. In the period 2000-2006, the census included feces on sidewalks surrounding the park. Thirty fresh fecal

  18. [Treatment of a 2,4-dichlorophenol contaminated wastewater in an air-lift inner-loop bioreactor].

    Science.gov (United States)

    Quan, Xiangchun; Zhang, Yongming; Wang, Jianlong; Shi, Hanchang; Qian, Yi

    2002-07-01

    An air lift inner-loop bioreactor packed with honeycomb-like ceramic carrier was immobilized with a 2,4-Dichlorophenol-degrading pure culture and was investigated to degrade 2,4-Dichlorophenol and phenol. In fed-batch operation mode, 2,4-DCP biodegradation rate increased with run numbers and followed zero-order kinetics model when it existed alone, but when 2,4-DCP was present in the mixture with phenol, phenol degradation rate had an apparent trend to increase whereas 2,4-DCP removal rate became slower and slower. In continuous operation, 2,4-DCP at the concentration ranged from 6.9 to 102.4 mg/L could be degraded well at the dilution rate of 0.16 h-1 and the average removal percentage was 96.5%. Carbon sources changed from 2,4-DCP to acetate sodium and peptone in the course of operation for 12 days did not cause the bacteria loss the DCP-degrading ability. PMID:12371101

  19. Assessing the combined influence of TOC and black carbon in soil–air partitioning of PBDEs and DPs from the Indus River Basin, Pakistan

    International Nuclear Information System (INIS)

    Levels of polybrominated diphenyl ethers (PBDEs) and dechlorane plus (DPs) were investigated in the Indus River Basin from Pakistan. Concentrations of ∑PBDEs and ∑DPs were ranged between 0.05 and 2.38 and 0.002–0.53 ng g−1 in the surface soils while 1.43–22.1 and 0.19–7.59 pg m−3 in the passive air samples, respectively. Black carbon (fBC) and total organic carbon (fTOC) fractions were also measured and ranged between 0.73 and 1.75 and 0.04–0.2%, respectively. The statistical analysis revealed strong influence of fBC than fTOC on the distribution of PBDEs and DPs in the Indus River Basin soils. BDE's congener profile suggested the input of penta–bromodiphenylether (DE-71) commercial formulation in the study area. Soil–air partitioning of PBDEs were investigated by employing octanol-air partition coefficients (KOA) and black carbon-air partition coefficients (KBC−A). The results of both models suggested the combined influence of total organic carbon (absorption) and black carbon (adsorption) in the studied area. - Highlights: • Model based calculations of black carbon-air partition coefficients for PBDEs. • Soil and air levels of PBDEs and DPs reported first time for ecologically important sites of the Indus River Basin, Pakistan. • Both, fBC and fTOC showed combined influence on soil–air partitioning of PBDEs in the Indus River Basin, Pakistan. - BC and TOC showed combined influence on soil–air partitioning of POPs i-e., PBDEs in the Indus River Basin, Pakistan

  20. Combining neutron and X-ray imaging to study air and water behaviour in the soil macropores

    Science.gov (United States)

    Snehota, Michal; Sobotkova, Martina; Jelinkova, Vladimira; Kaestner, Anders

    2016-04-01

    Infiltration of water and gas trapping in soil macropores were investigated on intact sample of coarse sandy loam soil (Cambisol series) taken from the B horizon by combined X-ray and neutron tomography imaging. The soil under study is known for the occurrence of the preferential flow, in which a majority of the water flux is conducted through small, highly conductive, fraction of the soil volume. Experiment performed in the NEUTRA beamline of Paul Scherrer Institut consisted of two infiltration episodes during which a layer of heavy and light water mixture was maintained on the sample surface created a ponding boundary condition. The initial state of the sample was recorded by one X-ray and two neutron scans prior to the first infiltration. Another 20 neutron tomograms were acquired during the following 25 hours of the experiment. Fine co-registration of the reconstructed X-ray and neutron tomograms was performed. Then, bi-variate histograms helped to identify the thresholds that were subsequently used for segmentation of the macropores from the X-ray tomograms. The segmented regions served as a binary mask for calculating the water volume using the neutron tomograms. Volume of water and subsequently the average water content in the macropore system were calculated. Results then quantitatively show the extent of the water content reduction in the macropores during the second infiltration that was caused by enhanced air trapping in the wet soil.

  1. Numerical analysis of air pollution in a combined field of land/sea breeze and mountain/valley wind

    International Nuclear Information System (INIS)

    Air pollution in the presence of two types of local flows (i.e., land/sea breeze and mountain/valley wind) was studies by advection simulation of the cluster of hypothetical fluid particles, and transport/chemistry calculation employing a three-dimensional Eulerian model for 20 advected species and about 90 chemical reactions. Three-dimensional flow fields over the River Yahagi basin in Japan were estimated for 48 h using an objective method with routine wind observations. Those obtained showed characteristics of the combined local flows such that in the daytime sea breeze and valley wind tend to form one united flow with substantial wind velocity in the whole region and, in contrast, land breeze and mountain wind during the nighttime form two separated circulating flows with a clear weak-wind area between the two local flow regimes. The results of the advection simulation of fluid particles and the transport/chemistry calculation using those flows as inputs elucidated how the features found in the diurnally varying, complex local flows contribute to produce characteristic time-variations of the concentrations of both primary and secondary pollutants. Among others, dynamics of NO2, HNO3, PAN, O3, SO2, and SO4/sup =/ concentrations are discussed

  2. Combined effects of predatory fish and sublethal pesticide contamination on the behavior and mortality of mayfly nymphs.

    Science.gov (United States)

    Schulz, R; Dabrowski, J M

    2001-11-01

    We evaluated the potential interaction of pesticide effect and predatory fish on behavior and mortality of a stream mayfly. Experiments in laboratory stream microcosms compared the activity, drift, and mortality of Baetis mayfly nymphs in the absence of fish with that in the presence of Cape galaxias (Galaxias zebratus), both species inhabiting the same stream environments in the Western Cape of South Africa. These two predator treatments were combined with exposure either to no pesticide or to 0.2 microg/L of the organophosphate insecticide azinphos-methyl (AZP) or 0.2 microg/L of the pyrethroid insecticide fenvalerate (FV). Such pesticide levels are known from transient spraydrift- or runoff-related pesticide input into running waters. Each of the six combinations was replicated six times as 30-min trials during the day and effects were analyzed using 2 x 2 factorial analysis of variance (ANOVA). A single exposure to either fish or pesticide significantly increased the absolute activity of mayflies, measured as number of animals visible on top of stones, and the absolute mayfly drift in the fish treatment and in the FV treatment but did not increase the mortality above 0.8%. The combination of predator presence and sublethal pesticide exposure resulted in a significant increase in the mortality rate, to about 9% in the AZP x fish and 25% in the FV x fish treatment, although the activity and drift rates were not increased compared with the single-stressor treatments. Two-by-two factorial ANOVA and the comparison of expected and measured responses indicated that the mortality resulted from a synergistic interaction of the two stressors. The observed mortality was without exception caused by predation of the fish on drifting mayflies. The relative drift rate in the FV x fish treatment was decreased, again due to a synergistic interaction, which suggests an active drift avoidance reaction of the mayflies exposed to the combined pesticide x fish treatment, in contrast

  3. Monitoring impacts of air pollution: PIXE analysis and histopathological modalities in evaluating relative risks of elemental contamination.

    Science.gov (United States)

    Ejaz, Sohail; Camer, Gerry Amor; Anwar, Khaleeq; Ashraf, Muhammad

    2014-04-01

    Environmental toxicants invariably affect all biological organisms resulting to sufferings ranging from subclinical to debilitating clinical conditions. This novel research aimed to determine the toxic burdens of increased environmental elements in some vital organs/tissues of the wild animals (starling, owl, crow and pigeon), exposed to air polluted environment were assessed using particle induced X-ray emission and histopathological approaches. The presence of significantly elevated amounts of elemental toxicants namely: Aluminum (Al), Chlorine (Cl), Iron (Fe), Potassium (K), Magnesium (Mg), Manganese (Mn), Silicon (Si) and Vanadium (V) from the skin, muscle, lungs, liver and kidney of sampled animals were in concurrence with the observed histopathological changes. The skin of sampled starling, owl, pigeon and crow spotlighted highly significant increase (P < 0.001) in Al, Cl, Mg and Si. Muscle samples with myodegenerative lesions and mineral depositions highlighted substantial augmentation (P < 0.001) in the amount of Al, Fe, Mn, Si and V. The lungs of starling, owl, and pigeon were severely intoxicated (P < 0.001) with increased amount of Al, Fe, K, Mn and Si producing pulmonary lesions of congestion, edema, pneumonitis and mineral debris depositions. Liver samples revealed that the sampled animals were laden with Cl, Fe, Mg, Mn and V with histopathological profound degenerative changes and hepatic necrosis. Kidney sections presented severe tubular degenerative and necrotic changes that may be attributed to increased amounts of Cl and Fe. These current findings implied that the environmental/elemental toxicants and the accompanying lesions that were discerned in the organs/tissues of sampled birds may as well be afflicting people living within the polluted area. Further assessment to more conclusively demonstrate correlations of current findings to those of the populace within the area is encouraged. PMID:24468923

  4. Assessment of Children’s Health and Indoor Air Contaminants of Day Care Centre in Industrial Area

    Directory of Open Access Journals (Sweden)

    Tezara CIONITA

    2015-10-01

    Full Text Available Background: Carbon dioxide (CO2 is one of the most commonly used indicators of indoor air quality (IAQ in industrial area. The higher concentration level of CO2 and particulate matter (PM10 in day care centre could affect children’s health. The objective of this study was to assess children’s health symptom, and measure the CO2 and PM10 concentration level as IAQ parameters in different locations of day care centres near the industrial area at Kuala Lumpur, Selangor and Hulu Langat as urban, suburban and rural areas respectively.Methods: The data of children’s health symptom were collected from the distributed questionnaire.Results: The day care centres (DCC in Kuala Lumpur has the highest number of children’s illness frequency of more than four times annually (11%, followed by the highest number of children who experienced asthma (5.3%, wheezing (3.3% and coughing (10%. The results of data collection of day care centres in Kuala Lumpur, Selangor and Hulu Langat ranged between 629-830 ppm, 587-823 ppm and 600-830 ppm for CO2 level, and 60.80-78.60 mg/m3, 56.90-80.50 mg/m3 and 59.90-79.10 mg/m3 for PM10 level. The statistical analysis for CO2 level between areas was significantly different (P<0.05.Conclusion: Day care centers in Kuala Lumpur have the highest mean rate of CO2 and PM10 as well as frequency of children’ illness which could identify traffic congestion and less greenery of a densely populated city. Keywords: Day care centre (DCC, IAQ, CO2, PM10, Health symptoms

  5. Influence of biochars, compost and iron grit, alone and in combination, on copper solubility and phytotoxicity in a Cu-contaminated soil from a wood preservation site.

    Science.gov (United States)

    Oustriere, Nadège; Marchand, Lilian; Galland, William; Gabbon, Lunel; Lottier, Nathalie; Motelica, Mikael; Mench, Michel

    2016-10-01

    Two biochars, a green waste compost and iron grit were used, alone and in combination, as amendment to improve soil properties and in situ stabilize Cu in a contaminated soil (964mgCukg(-1)) from a wood preservation site. The pot experiment consisted in 9 soil treatments (% w/w): untreated Cu-contaminated soil (Unt); Unt soil amended respectively with compost (5%, C), iron grit (1%, Z), pine bark-derived biochar (1%, PB), poultry-manure-derived biochar (1%, AB), PB or AB+C (5%, PBC and ABC), and PB or AB+Z (1%, PBZ and ABZ). After a 3-month reaction period, the soil pore water (SPW) was sampled in potted soils and dwarf beans were grown for a 2-week period. In the SPW, all amendments decreased the Cu(2+) concentration, but total Cu concentration increased in all AB-amended soils due to high dissolved organic matter (DOM) concentration. No treatment improved root and shoot DW yields, which even decreased in the ABC and ABZ treatments. The PBZ treatment decreased total Cu concentration in the SPW while reducing the gap with common values for root and shoot yields of dwarf bean plants. A field trial is underway before any recommendation for the PB-based treatments. PMID:27259036

  6. Combination of digital autoradiography and alpha track analysis to reveal the distribution of definite alpha- and beta-emitting nuclides in contaminated samples

    International Nuclear Information System (INIS)

    Digital autoradiography using Imaging Plate is commonly employed for searching 'hot' particles in the contaminated soil, sediment and aerosol probes. However digital radiography images combined with Alpha Track radiography data could provide much more information about micro-distribution of different alpha- and beta- nuclides. The discrimination method to estimate the distribution of radionuclides that are the main contributors to the total radioactivity (90Sr/90Y, 137Cs, 241Am) has been developed on the case of artificial reservoir V-17 (PA 'Mayak'). The bottom sediments and hydrobionts probes collected from V-17 along with the standards of 137Cs, 90Sr/90Y and 241Am have been exposed for a short time (15 min) using a stack of 3 Imaging Plates (Cyclone Plus Storage Phosphor System, Perkin Elmer). The attenuation of photostimulated luminescence (PSL) intensity from layer to layer of the Imaging Plates depends on the type and energy of radiation. Integrated approach using PSL attenuation in the samples and standards (digital radiography) along with Alpha Track radiography and gamma-spectroscopy of the preparation was used to estimate the contribution of the main nuclides in specific parts of contaminated samples. The observation of the 90Sr/90Y and 137Cs activity maxima could help to find the phases which are responsible for preferential sorption of the nuclides. Document available in abstract form only. (authors)

  7. The selection of plant species-organic amendment combinations aids to restore soil microbial function recovery in a metal-contaminated soil

    Science.gov (United States)

    Kohler, Josef; Caravaca, Fuensanta; Azcón, Rosario; Diáz, Gisela; Fuensanta, Garcia-Orenes; Roldan, Antonio

    2014-05-01

    A mesocosm experiment was established to evaluate the effect of two organic wastes: fermented sugar beet residue (SBR) and urban waste compost on the stimulation of plant growth, phytoaccumulation of heavy metals and soil biological quality and their possible use in phytostabilitation tasks with native (Piptatherum miliaceum, Retama sphaerocarpa, Bituminaria bituminosa, Coronilla juncea and Anthyllis cytisoides) and non-native (Lolium perenne) plants in a heavy metal contaminated semiarid soil. Excepting R. sphaerocarpa, SBR increased the contents of shoot N, P and K and shoot biomass of all plants. The percentage of mycorrhizal colonization was not affected by the organic amendments. The highest increase in dehydrogenase and β-glucosidase activities was recorded in SBR-amended P. miliaceum. SBR reduced toxic levels of HM in shoot of P. miliaceum, mainly decreasing Fe and Pb uptake to plants. This study pointed out that the SBR was the most effective amendment for enhancing the plant performance and for improving soil quality. The combination of SBR and P. miliaceum can be regarded the most effective strategy for being employed in phytostabilisation projects of this contaminated site.

  8. The Application of a Novel Pressurized Liquid Extraction Method to Quantify Organic Tracers Combined with Historic and Novel Organic Contaminants for the Discover-AQ Houston Field Experiment

    Science.gov (United States)

    Clark, A. E.; Yoon, S.; Sheesley, R. J.; Usenko, S.

    2014-12-01

    DISCOVER-AQ is a NASA mission seeking to better understand air quality in cities across the United States. In September 2013, flight, satellite and ground-based data was collected in Houston, TX and the surrounding metropolitan area. Over 300 particulate matter filter samples were collected as part of the ground-based sampling efforts, at four sites across Houston. Samples include total suspended particle matter (TSP) and fine particulate matter (less than 2.5 μm in aerodynamic diameter; PM2.5). For this project, an analytical method has been developed for the pressurized liquid extraction (PLE) of a wide variety of organic tracers and contaminants from quartz fiber filters (QFFs). Over 100 compounds were selected including polycyclic aromatic hydrocarbons (PAHs), hopanes, levoglucosan, organochlorine pesticides, polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), and organophosphate flame retardants (OPFRs). Currently, there is no analytical method validated for the reproducible extraction of all seven compound classes in a single automated technique. Prior to extraction, QFF samples were spiked with known amounts of target analyte standards and isotopically-labeled surrogate standards. The QFF were then extracted with methylene chloride:acetone at high temperatures (100˚C) and pressures (1500 psi) using a Thermo Dionex Accelerated Solvent Extractor system (ASE 350). Extracts were concentrated, spiked with known amounts of isotopically-labeled internal standards, and analyzed by gas chromatography coupled with mass spectrometry utilizing electron ionization and electron capture negative ionization. Target analytes were surrogate recovery-corrected to account for analyte loss during sample preparation. Ambient concentrations of over 100 organic tracers and contaminants will be presented for four sites in Houston during DISCOVER-AQ.

  9. Is there an environmental benefit from remediation of a contaminated site? Combined assessments of the risk reduction and life cycle impact of remediation

    DEFF Research Database (Denmark)

    Lemming, Gitte; Chambon, Julie Claire Claudia; Binning, Philip John;

    2012-01-01

    ), (iii) in-situ chemical oxidation (ISCO) with permanganate and (iv) long-term monitoring combined with treatment by activated carbon at the nearby waterworks. The life cycle assessment included evaluation of both primary and secondary environmental impacts. The primary impacts are the local human toxic...... impacts due to contaminant leaching into groundwater that is used for drinking water, whereas the secondary environmental impacts are related to remediation activities such as monitoring, drilling and construction of wells and use of remedial amendments. The primary impacts for the compared scenarios were...... higher environmental impacts than they remediate, in terms of person equivalents and assuming equal weighting of all impacts. The ERD and long-term monitoring were the scenarios with the lowest secondary life cycle impacts and are therefore the preferred alternatives. However, if activated carbon...

  10. Mapping of Cu and Pb Contaminations in Soil Using Combined Geochemistry, Topography, and Remote Sensing: A Case Study in the Le’an River Floodplain, China

    Directory of Open Access Journals (Sweden)

    Yin Gao

    2012-05-01

    Full Text Available Heavy metal pollution in soil is becoming a widely concerning environmental problem in China. The aim of this study is to integrate multiple sources of data, namely total Cu and Pb contents, digital elevation model (DEM data, remote sensing image and interpreted land-use data, for mapping the spatial distribution of total Cu and Pb contamination in top soil along the Le’an River and its branches. Combined with geographical analyses and watershed delineation, the source and transportation route of pollutants are identified. Regions at high risk of Cu or Pb pollution are suggested. Results reveal that topography is the major factor that controls the spatial distribution of Cu and Pb. Watershed delineation shows evidence that the streamflow resulting from rainfall is the major carrier of metal pollutants.

  11. Research on the water hammer protection of the long distance water supply project with the combined action of the air vessel and over-pressure relief valve

    International Nuclear Information System (INIS)

    We take a concrete pumping station as an example in this paper. Through the calculation of water hammer protection with a specific pumping station water supply project, and the analysis of the principle, mathematical models and boundary conditions of air vessel and over-pressure relief valve we show that the air vessel can protect the water conveyance system and reduce the transient pressure damage due to various causes. Over-pressure relief valve can effectively reduce the water hammer because the water column re-bridge suddenly stops the pump and prevents pipeline burst. The paper indicates that the combination set of air vessel and over-pressure relief valve can greatly reduce the quantity of the air valve and can eliminate the water hammer phenomenon in the pipeline system due to the vaporization and water column separation and re-bridge. The conclusion could provide a reference for the water hammer protection of long-distance water supply system

  12. Research on the water hammer protection of the long distance water supply project with the combined action of the air vessel and over-pressure relief valve

    Science.gov (United States)

    Li, D. D.; Jiang, J.; Zhao, Z.; Yi, W. S.; Lan, G.

    2013-12-01

    We take a concrete pumping station as an example in this paper. Through the calculation of water hammer protection with a specific pumping station water supply project, and the analysis of the principle, mathematical models and boundary conditions of air vessel and over-pressure relief valve we show that the air vessel can protect the water conveyance system and reduce the transient pressure damage due to various causes. Over-pressure relief valve can effectively reduce the water hammer because the water column re-bridge suddenly stops the pump and prevents pipeline burst. The paper indicates that the combination set of air vessel and over-pressure relief valve can greatly reduce the quantity of the air valve and can eliminate the water hammer phenomenon in the pipeline system due to the vaporization and water column separation and re-bridge. The conclusion could provide a reference for the water hammer protection of long-distance water supply system.

  13. The combined use of Skype and the STORZ CMAC video laryngoscope in field intubation training with the Nebraska National Air Guard.

    Science.gov (United States)

    Boedeker, Ben H; Bernhagen, Mary; Miller, David J; Miljkovic, Nikola; Kuper, Gail M; Murray, W Bosseau

    2011-01-01

    This study examined the feasibility of using Skype technology in basic manikin intubation instruction of Nebraska National Air Guard personnel at a Casualty Training Exercise. Results show that the Skype monitor provided clear sound and visualization of the airway view to the trainees and the combination of VoIP technology and videolaryngoscopy for intubation training was highly valued by study participants. PMID:21335766

  14. Source apportionment of air pollution in China: Extending the usefulness of receptor modeling by combining multivariate and chemical mass balance models

    International Nuclear Information System (INIS)

    The research explores the possibility of using a two step method of identifying and quantifying air pollution emissions in an urban environment. The procedures uses a mathematical model called Target Transformation Factor Analysis (TTFA) to estimate source profiles using ambient trace element air concentration data. A source profile is analogous to a fingerprint since it is unique to each source of air pollution. The profiles estimated by TTFA are then employed in a Chemical Mass Balance (CMB) source apportionment analysis for the air shed. Other known sources are estimated using source signatures from the literature. Applying the TTFA and CMB models in this fashion is called receptor modeling. Generically, a receptor model is the combination of measured air pollution concentration data with a numerical technique which apportions the measured air pollution among distinct source types. The results show that TTFA can be used to provide quantitative estimates of air pollution source profiles for an urban center in China. The number of profiles for unique source types was limited for the data set since emissions from certain types of sources co-varied during each sampling day. Consequently, the CMB analyses that applied the TTFA source profiles needed to be supplemented with standard U.S. EPA source profiles

  15. Optimized removal of dissolved organic carbon and trace organic contaminants during combined ozonation and artificial groundwater recharge.

    Science.gov (United States)

    Hübner, U; Miehe, U; Jekel, M

    2012-11-15

    Pilot scale experiments using an 8 g/h ozonation unit and a 1.4 m(2) slow sand filter have demonstrated that the combination of ozonation and artificial groundwater recharge is suitable for efficient reduction of bulk and trace organics. The biodegradation of dissolved organic carbon (DOC) in the slow sand filter was enhanced from 22% without pre-treatment to 34% by pre-ozonation. In addition, realistic surface water concentrations of most investigated trace organic compounds (TrOCs) including carbamazepine, sulfamethoxazole, phenazone and metoprolol were reduced below the limits of quantification. Only a few TrOCs, e.g. primidone and benzotriazole, were not efficiently removed in both treatment steps and could be detected regularly in the filter effluent. For these compounds, enhanced treatment, such as advanced oxidation processes, needs to be considered. Testing for genotoxicity and cytotoxicity did not reveal any systematic adverse effects for human health. The formation of the by-product bromate from bromide was below the limit of the German drinking water directive of 10 μg/L. No removal of bromate was observed in the aerobic slow sand filter. Additional experiments with sand columns showed that operating a preceding bank filtration step to reduce DOC can reduce oxidant demand by approximately 20%. PMID:23014565

  16. Integrated Assessment of PAH Contamination in the Czech Rivers Using a Combination of Chemical and Biological Monitoring

    Directory of Open Access Journals (Sweden)

    Jana Blahova

    2014-01-01

    Full Text Available This study investigated polycyclic aromatic hydrocarbons (PAH pollution of selected rivers in the Czech Republic. Integrated evaluation was carried out using combination of chemical and biological monitoring, in which we measured content of 1-hydroxypyrene (1-OHP in chub bile and priority PAH in water samples obtained by exposing the semipermeable membrane devices at each location. The concentrations of 1-OHP in bile samples and sum of priority PAH in water sampler ranged from 6.8 ng mg protein−1 to 106.6 ng mg protein−1 and from 5.2 ng L−1 to 173.9 ng L−1, respectively. The highest levels of biliary metabolite and PAH in water were measured at the Odra River (the Bohumín site, which is located in relatively heavily industrialized and polluted region. Statistically significant positive correlation between biliary 1-OHP and sum of PAH in water was also obtained (P<0.01, rs=0.806.

  17. Assessment of the contribution of the Koshkar-Ata tailing dump in contamination by radionuclides and heavy metals of ambient air in the area of Aktau city

    International Nuclear Information System (INIS)

    Full text: For a number of years Institute of Nuclear Physics of the National Nuclear Centre of the Republic of Kazakhstan (INP NNC RK) takes an active part in realization of a number of exploratory and environmental protection activities at the territory of Mangystau region. The outcomes of executed activities indicate that in Mangystau region a number of radiation hazardous objects of a different type are concentrated (numerous enterprises on oil production and processing, reactor BN-350 facilities, mining and reprocessing enterprises of uranium industry, sites of conducting of underground nuclear explosions), each of which introduces the definite contribution to formation of a general radioecological situation. Most complicated ecological conditions were developed around the Koshkar-Ata tailing dump, situated in 8 km to the east of the Caspian sea shore nearby the Aktau city, in 5 km to the north from industrial area and occupying all area of a natural valley 'Koshkar-Ata'. Since 1965 the blind valley Koshkar-Ata used including as a disposal area of waste of uranium industy. The volume of accumulated solid waste makes about 105 million tons, including waste with an enhanced level of concentrations of natural radionuclides about 52 million tons with total activity more that 10 000 Ci. The decrease of a level of aqueous phase caused by abrupt decline of volumes of industrial effluents has resulted in formation of the considerable areas of exposed bottom sediments being a source of toxic dust. In conditions of an arid climate of the study region, the wind erosion of radioactive sediments promotes raising them in atmosphere and distribution on the large areas. Within 2003-2004 the specialists of INP executed activities on development and installation of a system of monitoring contamination of ambient air by radionuclides and heavy metals. For realization of monitoring the technique of survey on contamination of ambient air was designed. The main method of

  18. Combined hydrolysis acidification and bio-contact oxidation system with air-lift tubes and activated carbon bioreactor for oilfield wastewater treatment.

    Science.gov (United States)

    Guo, Chunmei; Chen, Yi; Chen, Jinfu; Wang, Xiaojun; Zhang, Guangqing; Wang, Jingxiu; Cui, Wenfeng; Zhang, Zhongzhi

    2014-10-01

    This paper investigated the enhancement of the COD reduction of an oilfield wastewater treatment process by installing air-lift tubes and adding an activated carbon bioreactor (ACB) to form a combined hydrolysis acidification and bio-contact oxidation system with air-lift tubes (HA/air-lift BCO) and an ACB. Three heat-resistant bacterial strains were cultivated and subsequently applied in above pilot plant test. Installing air-lift tubes in aerobic tanks reduced the necessary air to water ratio from 20 to 5. Continuous operation of the HA/air-lift BCO system for 2 months with a hydraulic retention time of 36 h, a volumetric load of 0.14 kg COD/(m(3)d) (hydrolysis-acidification or anaerobic tank), and 0.06 kg COD/(m(3)d) (aerobic tanks) achieved an average reduction of COD by 60%, oil and grease by 62%, total suspended solids by 75%, and sulfides by 77%. With a COD load of 0.56 kg/(m(3)d), the average COD in the ACB effluent was 58 mg/L. PMID:25105268

  19. Application of cinder gel-beads/reeds combination strategy for bioremediation of pyrene- and indeno(1,2,3-cd)pyrene-contaminated estuarine wetlands.

    Science.gov (United States)

    Tian, Weijun; Liu, Qing; Huang, Ruying; Jin, Xin; Qiao, Kaili

    2016-06-01

    Pseudomonas putida PYR1 and Acinetobacter baumannii INP1 isolated from Liaohe estuarine wetlands were entrapped in cinder beads to make cinder gel-beads. They were combined with reeds for bioremediation of pyrene- and indeno(1,2,3-cd)pyrene-contaminated estuarine wetlands. The results showed that the removal percentages of pyrene and indeno(1,2,3-cd)pyrene (69.2 and 89.8 % respectively) in 40 days using cinder gel-beads/reeds were obviously higher than those using cinder gel-beads(52.6 and 70.0 %) and reeds (33.5 and 78.6 %) alone, about four times those of the control (13.8 and 31.1 %). The removal efficiency of pyrene was in the order cinder gel-beads/reeds > cinder gel-beads > reeds > control, which was different from cinder gel-beads/reeds > reeds > cinder gel-beads > control of indeno(1,2,3-cd)pyrene. This result indicated that the functional mechanism to remove indeno(1,2,3-cd)pyrene with six benzene rings was different from that of pyrene. The synergistic effect of reeds and cinder gel-beads for indeno(1,2,3-cd)pyrene removal was weaker than that of pyrene. But the absorption and transformation of reeds with high efficiency were beneficial to indeno(1,2,3-cd)pyrene removal from wetlands. Additionally, microbial analysis with high-throughput sequencing presented that Gammaproteobacteria were dominant PAH-degrading groups in bioremediation with immobilized bacteria. This strategy can serve as a model system for the removal of more complex or structurally related organic compounds from contaminated sites. PMID:26897584

  20. Measuring erosion rates of contaminated cohesive sediments using laboratory and in-situ devices in combination: experiences of investigations in River Elbe and Saale

    Science.gov (United States)

    Noack, Markus; Gerbersdorf, Sabine; Hillebrand, Gudrun; Kasimir, Petra; Wieprecht, Silke

    2014-05-01

    Deposition of contaminated sediments in areas of no or low flow velocity such as groyne fields or impounded river stretches represent a significant thread to water quality if long-deposited sediments are remobilized during flood and storm events. In contrast to non-cohesive sediments the dynamics of cohesive sediments is not fully understood mainly because of multiple physico-chemical factors and variable biological influence. Hence, site-specific investigations are required to develop water management strategies as well as modelling approaches to predict the dynamic behavior of cohesive material. The Institute for Modelling Hydraulic and Environmental Systems (IWS, University of Stuttgart) has a strong experience in developing measuring strategies and techniques to deal with the complex interactions between biological and sedimentary characteristics regarding erosion and remobilization of cohesive material. Specifically, the detection of critical shear stresses for incipient motion of cohesive particles has been realized for both one laboratory device (SETEG) and an in-situ device. For site-specific investigations ideally both methods should be combined. The first method (SETEG) includes the on-site extraction of sediment cores allowing for depth-dependent analysis under controlled laboratory conditions, while the second one measures the surface only but reduces possible artifacts due to sediment withdrawal and transport. Both methods were applied at groyne fields and deposition areas of the River Elbe and River Saale, which are both heavily affected by pollution of anthropogenic contaminants mainly originating from the release of chemical industry before 1990. Next to the detection of critical shear stresses and erosion rates, further sedimentary attributes are analyzed such as particle size distribution, water content and density as well as biological attributes such as TOC and microbial mass. The analyses of the sediment cores result in vertical profiles for

  1. Recovery of polypropylene and polyethylene from packaging plastic wastes without contamination of chlorinated plastic films by the combination process of wet gravity separation and ozonation.

    Science.gov (United States)

    Reddy, Mallampati Srinivasa; Okuda, Tetsuji; Nakai, Satoshi; Nishijima, Wataru; Okada, Mitsumasa

    2011-08-01

    Wet gravity separation technique has been regularly practiced to separate the polypropylene (PP) and polyethylene (PE) (light plastic films) from chlorinated plastic films (CP films) (heavy plastic films). The CP films including poly vinyl chloride (PVC) and poly vinylidene chloride (PVDC) would float in water even though its density is more than 1.0g/cm(3). This is because films are twisted in which air is sometimes entrapped inside the twisted CP films in real existing recycling plant. The present research improves the current process in separating the PP and PE from plastic packaging waste (PPW), by reducing entrapped air and by increasing the hydrophilicity of the CP films surface with ozonation. The present research also measures the hydrophilicity of the CP films. In ozonation process mixing of artificial films up to 10min reduces the contact angle from 78° to 62°, and also increases the hydrophilicity of CP films. The previous studies also performed show that the artificial PVDC films easily settle down by the same. The effect of ozonation after the wet gravity separation on light PPW films obtained from an actual PPW recycling plant was also evaluated. Although actual light PPW films contained 1.3% of CP films however in present case all the CP films were removed from the PPW films as a settled fraction in the combination process of ozonation and wet gravity separation. The combination process of ozonation and wet gravity separation is the more beneficial process in recovering of high purity PP and PE films from the PPW films. PMID:21530222

  2. Encouraging overweight students with intellectual disability to actively perform walking activity using an air mouse combined with preferred stimulation.

    Science.gov (United States)

    Chang, Chia-Jui; Chang, Man-Ling; Shih, Ching-Hsiang

    2016-08-01

    This study continues the research on using an air mouse as a physical activity detector. An air mouse is embedded with a MEMS (Micro Electro Mechanical Systems) gyro sensor, which can measure even the slightest movement in the air. The air mouse was strapped to one of each participant's calves to detect walking activity. This study was conducted to evaluate whether four students with intellectual disability who were overweight and disliked exercising could be motivated to engage in walking actively by linking the target response with preferred stimulation. Single-subject research with ABAB design was adopted in this study. The experimental data showed substantial increases in the participants' target responses (i.e. the performance of the activity of walking) during the intervention phases compared to the baseline phases. The practical and developmental implications of the findings are discussed. PMID:27037988

  3. Gas turbine engine adapted for use in combination with an apparatus for separating a portion of oxygen from compressed air

    Science.gov (United States)

    Bland, Robert J.; Horazak, Dennis A.

    2012-03-06

    A gas turbine engine is provided comprising an outer shell, a compressor assembly, at least one combustor assembly, a turbine assembly and duct structure. The outer shell includes a compressor section, a combustor section, an intermediate section and a turbine section. The intermediate section includes at least one first opening and at least one second opening. The compressor assembly is located in the compressor section to define with the compressor section a compressor apparatus to compress air. The at least one combustor assembly is coupled to the combustor section to define with the combustor section a combustor apparatus. The turbine assembly is located in the turbine section to define with the turbine section a turbine apparatus. The duct structure is coupled to the intermediate section to receive at least a portion of the compressed air from the compressor apparatus through the at least one first opening in the intermediate section, pass the compressed air to an apparatus for separating a portion of oxygen from the compressed air to produced vitiated compressed air and return the vitiated compressed air to the intermediate section via the at least one second opening in the intermediate section.

  4. A new procedure combining GC-MS with accelerated solvent extraction for the analysis of phthalic acid esters in contaminated soils

    Institute of Scientific and Technical Information of China (English)

    Tingting MA; Ying TENG; Peter CHRISTIE; Yongming LUO; Yongshan CHEN; Mao YE

    2013-01-01

    An optimized procedure based on gas chromatography-mass spectrometry (GC-MS) combined with accelerated solvent extraction (ASE) is developed for the analysis of six phthalic acid esters (PAEs), which are priority soil pollutants nominated by United States Environmental Protection Agency (USEPA). Quantification of PAEs in soil employs ultrasonic extraction (UE) (USEPA 3550) and ASE (USEPA 3545), followed by clean up procedures involving three different chromatography columns and two combined elution methods. GC-MS conditions under selected ion monitoring (SIM) mode are described and quality assurance and quality control (QA/ QC) criteria with high accuracy and sensitivity for target analytes were achieved. Method reliability is assured with the use of an isotopically labeled PAE, di-n-butyl phthalate-d4 (DnBP-D4), as a surrogate, and benzyl benzoate (BB) as an internal standard, and with the analysis of certified reference materials (CRM). QA/QC for the developed procedure was tested in four PAE-spiked soils and one PAE-contaminated soil. The four spiked soils were originated from typical Chinese agricultural fields and the contaminated soil was obtained from an electronic waste dismantling area. Instrument detection limits (IDLs) for the six PAEs ranged 0.10-0.31 μg·L-1 and method detection limits (MDLs) of the four spiked soils varied from a range of 20-70 μg· kg -1 to a range of 90-290 μg· kg-1. Lineal-iVy of response between 20 μg· L-1 and 2mg.L~ was also established and the correlation coefficients (R) were a11〉0.998. Spiked soil matrix showed relative recovery rates between 75 and 120% for the six target compounds and about 93% for the surrogate substance. The developed procedure is anticipated to be highly applicable for field surveys of soil PAE pollution in China.

  5. Combined current and temperature mapping in an air-cooled, open-cathode polymer electrolyte fuel cell under steady-state and dynamic conditions

    Science.gov (United States)

    Meyer, Q.; Ronaszegi, K.; Robinson, J. B.; Noorkami, M.; Curnick, O.; Ashton, S.; Danelyan, A.; Reisch, T.; Adcock, P.; Kraume, R.; Shearing, P. R.; Brett, D. J. L.

    2015-11-01

    In situ diagnostic techniques provide a means of understanding the internal workings of fuel cells so that improved designs and operating regimes can be identified. Here, for the first time, a combined current density and temperature distributed measurement system is used to generate an electro-thermal performance map of an air-cooled, air-breathing polymer electrolyte fuel cell stack operating in an air/hydrogen cross-flow configuration. Analysis is performed in low- and high-current regimes and a complex relationship between localised current density, temperature and reactant supply is identified that describes the way in which the system enters limiting performance conditions. Spatiotemporal analysis was carried out to characterise transient operations in dead-ended anode/purge mode which revealed extensive current density and temperature gradients.

  6. Tracking the fingerprints and combined TOC-black carbon mediated soil-air partitioning of polychlorinated naphthalenes (PCNs) in the Indus River Basin of Pakistan.

    Science.gov (United States)

    Ali, Usman; Sánchez-García, Laura; Rehman, Muhammad Yasir Abdur; Syed, Jabir Hussain; Mahmood, Adeel; Li, Jun; Zhang, Gan; Jones, Kevin C; Malik, Riffat Naseem

    2016-01-01

    This study reports the first investigation of polychlorinated naphthalenes (PCNs) in air and soil samples from ecologically important sites of the Indus River Basin, Pakistan. The concentrations of ∑39-PCNs in air and soil were found in a range between 1-1588 pg m(-3) and 0.02-23 ng g(-1) while the mean TEQ values were calculated to be 5.4E(-04) pg TEQ m(-3) and 1.6E(+01) pg TEQ g(-1), respectively. Spatially, air and soil PCN concentrations were found to be high at Rahim Yar Khan (agricultural region). Lower-medium chlorinated PCNs (sum of tri-, tetra- and penta-CNs) predominated in both air and soil, altogether constituting 87 and 86% of total PCNs in the two environmental matrices, respectively. According to the data, soil-air partitioning of PCNs was interpreted to be similarly controlled by the combined effect of black carbon and organic matter in the Indus River Basin, with no preferential implication of the recalcitrant organic form. PMID:26613673

  7. Lichens biomonitoring as feasible methodology to assess air pollution in natural ecosystems: Combined study of quantitative PAHs analyses and lichen biodiversity in the Pyrenees Mountains

    Energy Technology Data Exchange (ETDEWEB)

    Blasco, Maria; Domeno, Celia; Nerin, Cristina [Grupo GUIA-Instituto de Investigacion de Ingenieria en Aragon (I3A), Centro Superior de Ingenieros (CPS), Zaragoza (Spain)

    2008-06-15

    The air quality in the Aragon valley, in the central Pyrenees, has been assessed by evaluation of lichen biodiversity and mapped by elaboration of the Index of Air Purity (IAP) based on observations of the presence and abundance of eight kinds of lichen with different sensitivity to air pollution. The IAP values obtained have been compared with quantitative analytical measures of 16 PAHs in the lichen Evernia prunastri, because this species was associated with a wide range of traffic exposure and levels of urbanization. Analyses of PAHs were carried out by the DSASE method followed by an SPE clean-up step and GC-MS analysis. The concentration of total PAHs found in lichen samples from the Aragon valley ranged from 692 to 6420 ng g{sup -1} and the PAHs profile showed predominance of compounds with three aromatic rings. The influence of the road traffic in the area has been shown because values over the median concentration of PAHs (>1092 ng g{sup -1}), percentage of combustion PAHs (>50%), and equivalent toxicity (>169) were found in lichens collected at places exposed to the influence of traffic. The combination of both methods suggests IAP as a general method for evaluating the air pollution referenced to PAHs because it can be correlated with the content of combustion PAHs and poor lichen biodiversity can be partly explained by the air pollution caused by specific PAHs. (orig.)

  8. A combined cycle plant with air and fuel recuperator for captive power application, Part 1: Performance analysis and comparison with non-recuperated and gas turbine cycle with only air recuperator

    International Nuclear Information System (INIS)

    Highlights: • A combined gas–steam cycle for captive application is proposed and analyzed. • The cycle uses gas turbine exhaust heat for subsequent air and fuel preheating. • Further heat recuperation takes place for steam generation in the HRSG. • Effect of pressure ratio and steam injection to combustor on performance is studied. • Comparison with non-recuperated and cycle with only air recuperator is provided. - Abstract: In this paper, a simulation based performance of a recuperated combined gas turbine (GT) and steam turbine (ST) cycle is presented. The proposed combined cycle (CC) utilizes GT exhaust heat for air and fuel preheating sequentially one after the other. Comparison of performance of the recuperated CC is made with a non-recuperated CC and a CC with only the air recuperator (AR). At a compressor pressure ratio (CPR) of 12, the CC with both AR and fuel recuperator (FR) shows 16.8% and 54.44% gain in performance over the cycle with only the AR and no recuperators. A parametric study based on variation of CPR and steam injection rate (STIR) indicate improvement in efficiency and power with increase in CPR and STIR both. With CPR, the net GT power increases, however the net ST power shows a decreasing trend particularly for the cycle without recuperators. With STIR, the net GT power increases and the bottoming ST power although decreases but with less significance. The net ST power of the CC plant without recuperators is significantly less for the bottoming ST cycle to be economically feasible. The CC plant shows an average 53.32% gain in efficiency and power over the plant without the bottoming ST cycle

  9. Large scale air pollution estimation method combining land use regression and chemical transport modeling in a geostatistical framework

    NARCIS (Netherlands)

    Akita, Yasuyuki; Baldasano, Jose M.; Beelen, Rob; Cirach, Marta; De Hoogh, Kees; Hoek, Gerard; Nieuwenhuijsen, Mark; Serre, Marc L.; De Nazelle, Audrey

    2014-01-01

    In recognition that intraurban exposure gradients may be as large as between-city variations, recent air pollution epidemiologic studies have become increasingly interested in capturing within-city exposure gradients. In addition, because of the rapidly accumulating health data, recent studies also

  10. Verification of state and progress of a biological remediation of NAPL contaminated soil by the determination of radon concentration in soil air. Final report

    International Nuclear Information System (INIS)

    Some methods for recycling of soil which is contaminated with hydrocarbons like petrol or diesel are based on the admixture of active biological material in order to reduce the contamination. This mixture is stored on a dump for some months and the reduction of the contamination is checked by regular chemical analysis of some samples. Task of the research project is to replace these analysis by an investigation of Radon gas, which is present in the pore volume of the dumped soil. In two series of experiments at dumps with contaminated soil biologically treated, an increase of radon concentration in conjunction with a decrease of contamination was detected. But the recorded change of Radon was much less than expected and shows a significant dependence on environmental parameters like temperature or soil structure. At the present state of development the method is not yet suitable to replace conventional analysis during soil recycling. (orig.)

  11. Primary and secondary consequences of indoor air cleaners.

    Science.gov (United States)

    Siegel, J A

    2016-02-01

    Air cleaning is broadly applied to reduce contaminant concentrations in many buildings. Although diverse in underlying technology, mode of application, target contaminants, and effectiveness, there are also commonalities in the framework for understanding their primary impact (i.e. concentration reductions) and secondary impacts (e.g. energy use and by-product production). Furthermore, both primary and secondary impacts are moderated by the specific indoor context in which an air cleaner is used. This investigation explores the dynamics of removal efficiency in a variety of air cleaners and combines efficiency and flow rate to put air cleaning in the context of real indoor environments. This allows for the direct comparison to other indoor pollutant loss mechanisms (ventilation and deposition) and further suggests that effective air cleaner use is context and contaminant specific. The concentration reduction impacts of air cleaning need to be contrasted with the secondary consequences that arise from the use of air cleaners. This study emphasizes two important secondary consequences: energy use of the air cleaning process and primary and secondary emissions from air cleaners. This study also identifies current research challenges and areas for large leaps in our understanding of the role of air cleaners in improving indoor environmental quality. PMID:25689321

  12. Modeling for Airborne Contamination

    International Nuclear Information System (INIS)

    The objective of Modeling for Airborne Contamination (referred to from now on as ''this report'') is to provide a documented methodology, along with supporting information, for estimating the release, transport, and assessment of dose to workers from airborne radioactive contaminants within the Monitored Geologic Repository (MGR) subsurface during the pre-closure period. Specifically, this report provides engineers and scientists with methodologies for estimating how concentrations of contaminants might be distributed in the air and on the drift surfaces if released from waste packages inside the repository. This report also provides dose conversion factors for inhalation, air submersion, and ground exposure pathways used to derive doses to potentially exposed subsurface workers. The scope of this report is limited to radiological contaminants (particulate, volatile and gaseous) resulting from waste package leaks (if any) and surface contamination and their transport processes. Neutron activation of air, dust in the air and the rock walls of the drift during the preclosure time is not considered within the scope of this report. Any neutrons causing such activation are not themselves considered to be ''contaminants'' released from the waste package. This report: (1) Documents mathematical models and model parameters for evaluating airborne contaminant transport within the MGR subsurface; and (2) Provides tables of dose conversion factors for inhalation, air submersion, and ground exposure pathways for important radionuclides. The dose conversion factors for air submersion and ground exposure pathways are further limited to drift diameters of 7.62 m and 5.5 m, corresponding to the main and emplacement drifts, respectively. If the final repository design significantly deviates from these drift dimensions, the results in this report may require revision. The dose conversion factors are further derived by using concrete of sufficient thickness to simulate the drift

  13. Performance improvement of gas turbines of Fars (Iran) combined cycle power plant by intake air cooling using a media evaporative cooler

    Energy Technology Data Exchange (ETDEWEB)

    Hosseini, R.; Beshkani, A. [Mechanical Engineering Department, Amirkabir University of Technology, 424 Hafez Avenue, P.O. Box 15875-4413 Tehran (Iran); Soltani, M. [Mechanical Systems Department, Niroo Research Institute (NRI), End of Pounak Bakhtari Boulevard, P.O. Box 14665-517, Shahrak Gharb, Tehran (Iran)

    2007-04-15

    In this paper, a media evaporative cooling system installed in the gas turbines of the Fars (Iran) combined cycle power plant are modeled and evaluated. In this model, different design parameters such as inlet air velocity, geometric shape and sizes and depth of the media have been considered. Analysis of the results shows that at a constant Prandtl number, the cooler effectiveness decreases and pressure drop increases, as incoming air velocity increases. The water evaporation rate and temperature drop of the cooler have been calculated, and the effects of temperature, relative humidity and pressure of the ambient have been investigated as well. The practical and analytical results show that the output of a gas turbine of the Fars combined cycle power plant at 38 C ambient temperature and 8% relative humidity is 11 MW more, and the temperature drop of the inlet air is about 19 C with media evaporative cooling installations. Because of annual power augmentation of 5280 MWh and considering 2.5 Cents/kW h selling price for excess electricity generated, the payback period obtained is about four years. (author)

  14. Atmospheric contamination

    International Nuclear Information System (INIS)

    It is about the levels of contamination in center America, the population's perception on the problem, effects of the atmospheric contamination, effects in the environment, causes of the atmospheric contamination, possibilities to reduce the atmospheric contamination and list of Roeco Swisscontac in atmospheric contamination

  15. A Study of the Combined Effects of Physical Activity and Air Pollution on Mortality in Elderly Urban Residents

    DEFF Research Database (Denmark)

    Andersen, Zorana Jovanovic; de Nazelle, Audrey; Mendez, Michelle A;

    2015-01-01

    : To examine whether benefits of physical activity on mortality are moderated by long-term exposure to high air pollution levels in an urban setting. METHODS: 52,061 subjects (50-65 years) from the Danish Diet, Cancer, and Health cohort, living in Aarhus and Copenhagen reported data on physical activity...... in 1993-97 and were followed until 2010. High exposure to air pollution was defined as the upper 25th percentile of modelled nitrogen dioxide (NO2) levels at residential addresses. We associated participation in sports, cycling, gardening, and walking with total and cause-specific mortality by Cox...... regression, and introduced NO2 as an interaction term. RESULTS: 5,534 subjects died in total: 2,864 from cancer, 1,285 from cardiovascular disease, 354 from respiratory disease, and 122 from diabetes. Significant inverse associations of participation in sports, cycling, and gardening with total...

  16. Assessing the combined influence of TOC and black carbon in soil-air partitioning of PBDEs and DPs from the Indus River Basin, Pakistan.

    Science.gov (United States)

    Ali, Usman; Mahmood, Adeel; Syed, Jabir Hussain; Li, Jun; Zhang, Gan; Katsoyiannis, Athanasios; Jones, Kevin C; Malik, Riffat Naseem

    2015-06-01

    Levels of polybrominated diphenyl ethers (PBDEs) and dechlorane plus (DPs) were investigated in the Indus River Basin from Pakistan. Concentrations of ∑PBDEs and ∑DPs were ranged between 0.05 and 2.38 and 0.002-0.53 ng g(-1) in the surface soils while 1.43-22.1 and 0.19-7.59 pg m(-3) in the passive air samples, respectively. Black carbon (fBC) and total organic carbon (fTOC) fractions were also measured and ranged between 0.73 and 1.75 and 0.04-0.2%, respectively. The statistical analysis revealed strong influence of fBC than fTOC on the distribution of PBDEs and DPs in the Indus River Basin soils. BDE's congener profile suggested the input of penta-bromodiphenylether (DE-71) commercial formulation in the study area. Soil-air partitioning of PBDEs were investigated by employing octanol-air partition coefficients (KOA) and black carbon-air partition coefficients (KBC-A). The results of both models suggested the combined influence of total organic carbon (absorption) and black carbon (adsorption) in the studied area. PMID:25795070

  17. New radiological examination for tumor in the internal auditory canal by combination of air CT cisternography and target imaging

    Energy Technology Data Exchange (ETDEWEB)

    Yagishita, A.; Shiga, I.; Kanzaki, H. (Keio Univ., Tokyo (Japan). School of Medicine)

    1982-07-01

    A 56-year-old man was admitted to the hospital because of progressive right hearing disturbance and tinnitus. An x-ray film of the skull demonstrated dilatation of the right internal auditory canal. Intravcnously enhanced CT didn't reveal any tumor in the right cerebellopontine angle. An intracanalicular tumor was demonstrated by air CT cisternography with target imaging, and confirmed by surgery. This method is useful for the radiological evaluation of the intracanalicular tumors.

  18. Long-term (1992-2004) record of lead, cadmium, and zinc air contamination in Warsaw, Poland: Determination by chemical analysis of moss bags and leaves of Crimean linden

    International Nuclear Information System (INIS)

    Between 1992 and 2004, air contamination with lead (Pb), cadmium (Cd), and zinc (Zn) in Warsaw, Poland, was monitored annually with moss (Sphagnum fallax) bags on a network of 230 sites covering the entire city. During the study the highest contamination was near the Warszawa Steel Mill, northwestern Warsaw. Lead concentrations in moss bags decreased in time, while those of Cd and Zn did not show clear trends. Between 1994 and 2004, Pb, Cd, and Zn were also monitored in the Crimean linden (Tilia Euchlora) foliage along the main city avenue and in a northwestern warsaw park. Lead concentrations decreased more near the avenue than in the park, indicating that the phasing-out of leaded gasoline had a major effect on reduced Pb contamination in Warsaw. At the same time, foliar concentrations of Cd and Zn in both areas decreased much less. - Between 1992 and 2004, concentrations of Pb decreased, while those of Cd and Zn remained little changed in moss bags and linden foliage exposed to ambient air in Warsaw, Poland.

  19. Long-term (1992-2004) record of lead, cadmium, and zinc air contamination in Warsaw, Poland: Determination by chemical analysis of moss bags and leaves of Crimean linden

    Energy Technology Data Exchange (ETDEWEB)

    Dmuchowski, Wojciech, E-mail: dmuchowski@ob.neostrada.p [Botanical Garden-Center for Conservation of Biological Diversity, Polish Academy of Sciences, 2 Prawdziwka St., 02-973 Warszawa (Poland); Warsaw University of Life Sciences-SGGW, Faculty of Agriculture and Biology, 159 Nowoursynowska St., 02-776 Warszawa (Poland); Bytnerowicz, Andrzej [US Forest Service, Pacific Southwest Research Station, 4955 Canyon Crest Drive, Riverside, CA 92507 (United States)

    2009-12-15

    Between 1992 and 2004, air contamination with lead (Pb), cadmium (Cd), and zinc (Zn) in Warsaw, Poland, was monitored annually with moss (Sphagnum fallax) bags on a network of 230 sites covering the entire city. During the study the highest contamination was near the Warszawa Steel Mill, northwestern Warsaw. Lead concentrations in moss bags decreased in time, while those of Cd and Zn did not show clear trends. Between 1994 and 2004, Pb, Cd, and Zn were also monitored in the Crimean linden (Tilia Euchlora) foliage along the main city avenue and in a northwestern warsaw park. Lead concentrations decreased more near the avenue than in the park, indicating that the phasing-out of leaded gasoline had a major effect on reduced Pb contamination in Warsaw. At the same time, foliar concentrations of Cd and Zn in both areas decreased much less. - Between 1992 and 2004, concentrations of Pb decreased, while those of Cd and Zn remained little changed in moss bags and linden foliage exposed to ambient air in Warsaw, Poland.

  20. Air Cleaning Technologies

    Science.gov (United States)

    2005-01-01

    Executive Summary Objective This health technology policy assessment will answer the following questions: When should in-room air cleaners be used? How effective are in-room air cleaners? Are in-room air cleaners that use combined HEPA and UVGI air cleaning technology more effective than those that use HEPA filtration alone? What is the Plasmacluster ion air purifier in the pandemic influenza preparation plan? The experience of severe acute respiratory syndrome (SARS) locally, nationally, and internationally underscored the importance of administrative, environmental, and personal protective infection control measures in health care facilities. In the aftermath of the SARS crisis, there was a need for a clearer understanding of Ontario’s capacity to manage suspected or confirmed cases of airborne infectious diseases. In so doing, the Walker Commission thought that more attention should be paid to the potential use of new technologies such as in-room air cleaning units. It recommended that the Medical Advisory Secretariat of the Ontario Ministry of Health and Long-Term Care evaluate the appropriate use and effectiveness of such new technologies. Accordingly, the Ontario Health Technology Advisory Committee asked the Medical Advisory Secretariat to review the literature on the effectiveness and utility of in-room air cleaners that use high-efficiency particle air (HEPA) filters and ultraviolet germicidal irradiation (UVGI) air cleaning technology. Additionally, the Ontario Health Technology Advisory Committee prioritized a request from the ministry’s Emergency Management Unit to investigate the possible role of the Plasmacluster ion air purifier manufactured by Sharp Electronics Corporation, in the pandemic influenza preparation plan. Clinical Need Airborne transmission of infectious diseases depends in part on the concentration of breathable infectious pathogens (germs) in room air. Infection control is achieved by a combination of administrative, engineering

  1. System Design of Capillary Radiation Air Conditioning Combined with Independent Fresh Air Unit%毛细管辐射空调结合独立新风的系统设计

    Institute of Scientific and Technical Information of China (English)

    雷会玉; 余晓明; 朱祥政; 张晓

    2014-01-01

    Nowadays, Central air conditioning system is more focusing on energy efficiency, comfort and environmentally friendly. Capillary radiant air conditioning is kind of excellent system with high comfort, low energy consumption and low noise. In the present paper, a new type of energy conservation air conditioning system is presented:ground source heat pump combined with capillary radiation and independent fresh air, in which lower temperature cold water is used to absorb the latent heat, while higher temperature cold water is used to absorb the sensible heat. The system can reduce air pollution and save energy. In the present paper, the advantage of energy performance and indoor air quality of the system is analyzed, besides that, the air processing and design of an example are also calculated and analyzed.%当今中央空调技术正朝着节能、舒适和环保的方向发展,毛细管辐射空调系统以其舒适性高、耗能低、噪声小的突出优势,在各种空调系统中脱颖而出。本文提出了一种新型的绿色节能空调系统设计思路:毛细管辐射-独立新风系统一体机的地源热泵空调系统。该系统采用地源热泵制取低温冷水承担潜热负荷,高温冷水承担显热负荷的方式,达到了节约高品位电能、减轻大气污染、减少运行费用的效果。文中分析了其在节能和舒适性方面的优势,并结合实例对该系统的空气处理过程和设计进行了相关计算与分析。

  2. Combining Shapley value and statistics to the analysis of gene expression data in children exposed to air pollution

    Directory of Open Access Journals (Sweden)

    Kleinjans Jos

    2008-09-01

    Full Text Available Abstract Background In gene expression analysis, statistical tests for differential gene expression provide lists of candidate genes having, individually, a sufficiently low p-value. However, the interpretation of each single p-value within complex systems involving several interacting genes is problematic. In parallel, in the last sixty years, game theory has been applied to political and social problems to assess the power of interacting agents in forcing a decision and, more recently, to represent the relevance of genes in response to certain conditions. Results In this paper we introduce a Bootstrap procedure to test the null hypothesis that each gene has the same relevance between two conditions, where the relevance is represented by the Shapley value of a particular coalitional game defined on a microarray data-set. This method, which is called Comparative Analysis of Shapley value (shortly, CASh, is applied to data concerning the gene expression in children differentially exposed to air pollution. The results provided by CASh are compared with the results from a parametric statistical test for testing differential gene expression. Both lists of genes provided by CASh and t-test are informative enough to discriminate exposed subjects on the basis of their gene expression profiles. While many genes are selected in common by CASh and the parametric test, it turns out that the biological interpretation of the differences between these two selections is more interesting, suggesting a different interpretation of the main biological pathways in gene expression regulation for exposed individuals. A simulation study suggests that CASh offers more power than t-test for the detection of differential gene expression variability. Conclusion CASh is successfully applied to gene expression analysis of a data-set where the joint expression behavior of genes may be critical to characterize the expression response to air pollution. We demonstrate a

  3. Vibration Analysis and Control for Combined Air-preheater of Coking Furnace%焦化加热炉空气预热器振动及减振

    Institute of Scientific and Technical Information of China (English)

    颜祥富; 侯杰; 龙运国

    2013-01-01

    The combined air-preheater produces strong vibration when the coking furnace is working. In this paper, it was pointed out that the resonance caused by Carmen vortex is the main reason for the strong vibration of the air-preheater. To avoid the resonance, the Carmen vortex frequency of the heat-transfer-tube was adjusted so that it would not coincide with the natural frequency of the chamber any more. Through the improvement, the vibration of the air-proheater was eliminated, and the normal operation of the preheater was resumed.%  焦化装置组合式空气预热器试运行时产生强烈振动,对组合式空气预热器产生振动的原因进行分析,卡门涡流是预热器产生振动的主要原因。提出合理的消振方案,通过改造,该预热器消除了振动,恢复了正常的运行。

  4. Bar coded air sample tracking and bar coded loose surface contamination sample tracking: How it can assist in compliance with the DOE's new 10 CFR 835 and the NRC's new 10 CFR 20 regulations

    International Nuclear Information System (INIS)

    The paper describes advance sample tracking and processing techniques which utilize bar code technology for field data collection and count room analysis. Techniques described by the paper include bar coded area air sampling, bar coded portable breathing zone air sampling, and bar coded loose surface contamination sampling. Bar coded sample tracking is explored to demonstrate how it can assist in compliance with new DOE 10 CFR 835 and NRC 10 CFR 20 requirements. Operation of portable bar code readers is explored to provide insight to the advantages of bar coded sample tracking and corresponding sample trending analyses. Case studies involving bar coded sample tracking systems which are in use at NRC facilities, DOE sites, and decommission projects are discussed

  5. Development of an automatic continuous analyzer for water-soluble gases in air by combining an artificial lung with an ion chromatograph

    Science.gov (United States)

    Sakamoto, Kazuhiko; Takeno, Masaki; Sekiguchi, Kazuhiko; Ishitani, Osamu; Fukuyama, Tsutomu; Utiyama, Masahiro

    An automatic measurement system for the simultaneous monitoring of sulfur dioxide (SO 2) and ammonia (NH 3) in air was developed by combining an artificial lung and an ion chromatograph. An artificial lung was used as a new technique for concentrated collection of trace amounts of gaseous pollutants in air. It was found that SO 2 and NH 3 were effectively absorbed into ultra-pure water in the artificial lung. Collection efficiencies for SO 2 and NH 3 were 100% and 98%, respectively, at a gas flow rate of 1 l min -1, and material balances >90% were obtained. No interference from the simultaneous collection of SO 2 and NH 3 was found. When a 400 ppb standard NH 3 gas was measured automatically with this system, the recovery rate was 98%, and the relative standard deviation was 2.7% ( n=8). In the case of a 200 ppb standard SO 2 gas, the recovery rate was 87%, and the relative standard deviation was 1.6% ( n=7). Results from the simultaneous measurement of SO 2 and NH 3 with the automatic system were equally as good as those obtained by measuring a single component at a time. Calibration curves for SO 2 and NH 3 showed good relationships between concentration and peak intensity. The linear correlation coefficients were 0.997 and 0.998 for SO 2 and NH 3, respectively. The detection limits of SO 2 and NH 3 were 0.06 and 0.1 ppb, respectively, in a 40 l air volume. The system was tested in air and found to be capable of simultaneous measurement of SO 2 and NH 3 with a 20 min cycle.

  6. Surface modification on a glass surface with a combination technique of sol–gel and air brushing processes

    KAUST Repository

    Tsai, Meng-Yu

    2011-08-01

    This study fabricated the large area and optically transparent superhydrophobic silica based films on glass surface with optimized hardness. A silane coupling agent, tetraethoxysilane (TEOS), effectively bonds silica particles onto the glass substrate. Desired surface roughness was obtained by adjusting nano silica particles concentration of the precursors prepared by the sol-gel process. Silica suspension was coated onto the glass substrate by the air brushing methods. This method can deposit a uniform, transparent coating on the glass substrate efficiently. Diluting the precursor by adding ethanol or a mixture of D.I. water and ethanol further improved the transmittance and superhydrophobicity efficiency. The results showed that as the silica particle concentration and the thickness of the coating were increased, the surface roughness was enhanced. Rougher surface displayed a higher superhydrophobicity and lower transmittance. Therefore, the concentration of silica particle, volume of coatings, and the ratio of ethanol and D.I. water are of great importance to deposit a transparent, superhydrophobic coating on glass. © 2011 Elsevier B.V. All rights reserved.

  7. Single and combined effects of air pollutants on circulatory and respiratory system-related mortality in Belgrade, Serbia.

    Science.gov (United States)

    Stojić, Svetlana Stanišić; Stanišić, Nemanja; Stojić, Andreja; Šoštarić, Andrej

    2016-01-01

    The aim of this study was to investigate the association between short- and long-term exposure to particulate matter (PM10), nitrogen dioxide (NO2), sulfur dioxide (SO2), and soot and mortality attributed to circulatory and respiratory diseases in Belgrade area (Serbia). The analyzed data set comprised results of regular pollutant monitoring and corresponding administrative records on frequency of daily mortality in the period 2009-2014. Nonlinear exposure-response dependencies and delayed effects of temperature were examined by means of distributed lag nonlinear models. The air pollutant loadings and circulatory system-related death rates in Belgrade area are among the highest in Europe. Data demonstrated that excess risk of death with short-term exposure to elevated concentrations of PM10, SO2, and soot was not significant, whereas marked effect size estimates for exposure over 90 d preceding mortality were found. The influence of chronic exposure was shown to be greater for respiratory than circulatory system-related mortality. When stratified by age and gender, higher risk was noted for male individuals below the age of 65 years. PMID:26699658

  8. Experimental synergy combining lidar measurements so as to optically characterize aerosols: applications to air quality and radiative forcing

    International Nuclear Information System (INIS)

    The work carried out in this study is devoted to a better understanding of the evolution of aerosol physical, chemical and optical properties for urban pollution aerosols, dust and biomass burning particles. It mainly concerns the complex refractive index and the single-scattering albedo. Such a characterisation is indeed necessary so as to fulfil the requirements of scientific and societal air quality and global climate evolution questions. Our study is based on a synergy between different measurements platforms: ground-based or airborne measurements, together with active and passive remote sensing observations. Lidar in particular turns out to be an essential tool in order to assess horizontal and vertical variability of aerosol micro-physical and optical properties in the atmospheric boundary layer, but also in the residual layer, as well as in layers transported from the boundary layer to the free troposphere. The original methodology we developed highlights the importance of the geographical origin, the impact of aging and dynamical processes in the evolution of structural, optical and hygroscopic aerosol features. The related accurate determination of the properties in each aerosol layer is required for radiative fluxes and heating rates calculations in the atmospheric column. The radiative impact of both dust particles and biomass burning aerosols observed over the region of Niamey (Niger) was thus assessed during the dry season. These results reveal the need of a better characterisation of those significant aerosol properties for each layer in models. (author)

  9. Enhancement of the microbial community biomass and diversity during air sparging bioremediation of a soil highly contaminated with kerosene and BTEX

    Czech Academy of Sciences Publication Activity Database

    Kabelitz, N.; Macháčková, I.; Imfeld, G.; Brennerová, Mária; Pieper, D. H.; Heipieper, H. J.; Junca, H.

    2009-01-01

    Roč. 82, - (2009), s. 565-577. ISSN 0175-7598 Institutional research plan: CEZ:AV0Z50200510 Keywords : btex * air sparging * bioremediation Subject RIV: EE - Microbiology, Virology Impact factor: 2.896, year: 2009

  10. Micrometeorological methods for measurements of mercury emissions over contaminated soils

    International Nuclear Information System (INIS)

    As part of a larger study involving development and application of field and laboratory methods (micrometeorological, dynamic enclosure chamber, and controlled laboratory chamber methods) to measure the air/surface exchange of Hg vapor, we performed a series of preliminary measurements over contaminated soils. From March--April 1993, we used the modified Bowen ratio (MBR) method to measure emission rates of mercury over a floodplain contaminated with mercury near Oak Ridge, TN. The mercury emission rates measured from contaminated EFPC soils using the MBR method during early spring show that (1) in all cases, the contaminated soils acted as a source of mercury to the atmosphere with source strengths ranging from 17 to 160 ng m-2 h-1; and (2) the strengths of mercury emissions can be greatly influenced by the combined effects of surface soil temperature, residence time of air masses over the source area, and turbulence conditions. The mercury fluxes measured in a controlled flow chamber indicate that contaminated soils can exhibit up to an order of magnitude higher emission rates of Hg under conditions of elevated soil temperature, soil structure disturbance, and high turbulence. Mercury emissions from contaminated soils exceeded emissions from background soils by one to two orders of magnitude

  11. The lichen Parmelia physodes (L. Ach. as indicator for determination of the degree of atmospheric air pollution in the area contaminated by flourine and sulphur dioxide emission

    Directory of Open Access Journals (Sweden)

    M. Świeboda

    2015-05-01

    Full Text Available On the area involved in the influence of conteminations emitted by the aluminium works and electric power plant, the degree of atmospheric air pollution was evaluated on the basis of the behaviour of healthy thallus of the lichen Parmelia physodes, analysis of fluorine and sulphur content in this thallus and in the bark substrate and the F and SO2 concentrations in the air.

  12. Radiant Floor Cooling Combined with Mixing Ventilation in a Residential Room

    DEFF Research Database (Denmark)

    Krajcik, Michal; Simone, Angela; Tomasi, Roberta;

    progress. An experimental laboratory study in a simulated residential room with a seated occupant simulated by a thermal manikin was performed in order to evaluate thermal comfort and ventilation effectiveness. Thermal comfort was evaluated by means of vertical air temperature and air velocity profiles and...... limits for comfortable thermal environment recommended by the standards. The cooler supply air mixed well and the effect of the position of air terminal devices was small. When warm unconditioned outside air was supplied by mixing ventilation in combination with the radiant floor cooling, low floor...... by thermal manikin equivalent temperatures. Contaminant removal effectiveness and air change efficiency were used to characterize the ventilation effectiveness. The vertical air temperature differences that occurred when floor cooling was combined with cold conditioned air supply were well within the...

  13. New combined models for estimating daily global solar radiation from measured air temperature in semi-arid climates: Application in Ghardaïa, Algeria

    International Nuclear Information System (INIS)

    Highlights: • New combined models been introduced for estimating daily global solar radiation. • The BNN is the most accurate model compared with combined models. • Results indicate that the new calibrated models are able to estimate the global solar. - Abstract: In this paper, combined empirical models and a Bayesian neural network (BNN) model have been developed to estimate daily global solar radiation (GSR) on a horizontal surface in Ghardaïa, Algeria. An experimental database of daily GSR, maximum and minimum air temperatures of the year 2006 has been used to estimate the coefficients of the empirical models, as well as to train the BNN model. Six months of the year 2007 (summer period: May, June, July, and winter period: October, November, December) have been used to test the calibrated models, while six months of the year 2012 (from 1st February to 31th July) have been used to check generalisation capability of the developed models as well as the BNN model. Results indicate that the new calibrated models are able to estimate the global solar radiation with an excellent accuracy in this location. Calibrated models are also compared with the developed BNN model to show their effectiveness

  14. Etiology of contaminated wounds

    International Nuclear Information System (INIS)

    The US Department of Energy reports of events that occurred in the chemical processing 200 Areas of the Hanford Site during the period from 1972 through 1986 were reviewed to identify the causes of contaminated wounds. Contaminated wounds were reported in 19 events involving 20 workers. The causal agents (high risk operations) and the root causes were characterized. Emergency actions taken and their efficacy were noted. The 19 wound events were compared with 17 events with the potential for inhalation. It was found that the wound events involve a single worker and frequently result in an internal contamination and its resulting dose. Inhalation events involve groups of workers and rarely resulted in detectable internal contamination. The difference is attributed to anticipation of an inhalation event and use of respiratory protection and continuous air monitors to mitigate its effects

  15. Turnkey Heating, Ventilating, and Air Conditioning and Lighting Retrofit Solution Combining Energy Efficiency and Demand Response Benefits

    Energy Technology Data Exchange (ETDEWEB)

    Doebber, Ian [National Renewable Energy Lab. (NREL), Golden, CO (United States); Deru, Michael [National Renewable Energy Lab. (NREL), Golden, CO (United States); Trenbath, Kim [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2016-04-12

    NREL worked with the Bonneville Power Administration's Technology Innovation Office to demonstrate a turnkey, retrofit technology that combines demand response (DR) and energy efficiency (EE) benefits for HVAC and lighting in retail buildings. As a secondary benefit, we also controlled various plug loads and electric hot water heaters (EHWH). The technology demonstrated was Transformative Wave's eIQ Building Management System (BMS) automatically responding to DR signals. The BMS controlled the HVAC rooftop units (RTU) using the CATALYST retrofit solution also developed by Transformative Wave. The non-HVAC loads were controlled using both hardwired and ZigBee wireless communication. The wireless controllers, manufactured by Autani, were used when the building's electrical layout was too disorganized to leverage less expensive hardwired control. The six demonstration locations are within the Seattle metro area. Based on the assets curtailed by the BMS at each location, we projected the DR resource. We were targeting a 1.7 W/ft2 shed for the summer Day-Ahead events and a 0.7 W/ft2 shed for the winter events. While summarized in Table ES-1, only one summer DR event was conducted at Casino #2.

  16. Research advances on air contaminant transport in ship cabin%船舶舱室污染物传播研究进展

    Institute of Scientific and Technical Information of China (English)

    周爱民; 余涛; 沈旭东

    2014-01-01

    According to the characteristics of ship cabin, this paper has systematically summarized the related researches for indoor contaminant transport into three kinds of typical methods, and evaluated their advantages and disadvantages. Through analyzing above ship theory models in the application situation and prospect, points out that their integration use is the development direction to simulate the ship cabin contaminant transport law. Finally this paper suggests the next step research direction, which has import reference value for the cabin contaminant transport.%针对船舶舱室特点,将相关室内污染物传播研究成果系统地总结成3类典型方法,并评价各自优缺点。通过分析各类理论模型在船舶领域的应用现状和前景,指出将其整合运用是模拟船舶舱室污染物传播规律的发展方向,并提出下一步的研究方向,对开展传播舱室污染物的研究具有重要参考价值。

  17. Airborne radioactive contamination monitoring

    International Nuclear Information System (INIS)

    Current technologies for the detection of airborne radioactive contamination do not provide real-time capability. Most of these techniques are based on the capture of particulate matter in air onto filters which are then processed in the laboratory; thus, the turnaround time for detection of contamination can be many days. To address this shortcoming, an effort is underway to adapt LRAD (Long-Range-Alpha-Detection) technology for real-time monitoring of airborne releases of alpa-emitting radionuclides. Alpha decays in air create ionization that can be subsequently collected on electrodes, producing a current that is proportional to the amount of radioactive material present. Using external fans on a pipe containing LRAD detectors, controlled samples of ambient air can be continuously tested for the presence of radioactive contamination. Current prototypes include a two-chamber model. Sampled air is drawn through a particulate filter and then through the first chamber, which uses an electrostatic filter at its entrance to remove ambient ionization. At its exit, ionization that occurred due to the presence of radon is collected and recorded. The air then passes through a length of pipe to allow some decay of short-lived radon species. A second chamber identical to the first monitors the remaining activity. Further development is necessary on air samples without the use of particulate filtering, both to distinguish ionization that can pass through the initial electrostatic filter on otherwise inert particulate matter from that produced through the decay of radioactive material and to separate both of these from the radon contribution. The end product could provide a sensitive, cost-effective, real-time method of determining the presence of airborne radioactive contamination

  18. New method of measurement IN VIVO Combination internal whole body with high-resolution germanium detectors. Rapid response in cross-contamination v

    International Nuclear Information System (INIS)

    This test method is a substantial improvement on the current capacities of the Personal Internal Dosimetry Service CIEMAT, as it will in a very short time make accurate measurements in vivo, excellent resolution and low background radiation environment in geometry whole body. The method will complement the existing laboratory [3] and may be used in emergencies or radiological accident in which the complexity of measuring spectra (cross contamination, multipicos interference) require a higher spectral resolution. (Author)

  19. Contamination monitoring activities in Kanupp

    Energy Technology Data Exchange (ETDEWEB)

    Naqvi, S.S. [Karachi Nuclear Power Plant (Pakistan)

    1997-06-01

    The Karachi Nuclear Power Plant (Kanupp) is a 137 MWe pressurized heavy water reactor, designed and erected by the Canadian General Electric Company as a turn key project. The plant is in operation since it was commissioned in the year 1972. It is located at the Arabian Sea Coast about 15 miles to the west of Karachi. During its more than two decades of operation, the plant has generated about 8 billion units of electricity with an average life time availability factor of 60%. In Kanupp, radioactive contamination may exit due to the release of fission product, activation products etc., which may somehow escape from its confinement and may contaminate surface or other media such as air, water etc. In this paper, following items are described: main aspects of contamination, status of contamination monitoring, need of contamination monitoring, radiation protection activity, instruments, contamination, current status of contamination survey materials and their disposal, and environmental monitoring. (G.K.)

  20. Determination of Zinc, Cadmium and Lead Bioavailability in Contaminated Soils at the Single-Cell Level by a Combination of Whole-Cell Biosensors and Flow Cytometry

    Directory of Open Access Journals (Sweden)

    Quentin Hurdebise

    2015-04-01

    Full Text Available Zinc, lead and cadmium are metallic trace elements (MTEs that are widespread in the environment and tend to accumulate in soils because of their low mobility and non-degradability. The purpose of this work is to evaluate the applicability of biosensors as tools able to provide data about the bioavailability of such MTEs in contaminated soils. Here, we tested the genetically-engineered strain Escherichia coli pPZntAgfp as a biosensor applicable to the detection of zinc, lead and cadmium by the biosynthesis of green fluorescent protein (GFP accumulating inside the cells. Flow cytometry was used to investigate the fluorescence induced by the MTEs. A curvilinear response to zinc between 0 and 25 mg/L and another curvilinear response to cadmium between 0 and 1.5 mg/L were highlighted in liquid media, while lead did not produce exploitable results. The response relating to a Zn2+/Cd2+ ratio of 10 was further investigated. In these conditions, E. coli pPZntAgfp responded to cadmium only. Several contaminated soils with a Zn2+/Cd2+ ratio of 10 were analyzed with the biosensor, and the metallic concentrations were also measured by atomic absorption spectroscopy. Our results showed that E. coli pPZntAgfp could be used as a monitoring tool for contaminated soils being processed.

  1. Indigenous and Contaminant Microbes in Ultradeep Mines

    Science.gov (United States)

    Onstott, T. C.; Moser, D. P.; Pfiffner, S. M.; Fredrickson, J. K.; Brockman, F. J.; Phelps, T. J.; White, D. C.; Peacock, A.; Balkwill, D.; Hoover, R. B.; Krumholz, L. R.; Borscik, M.; Kieft, T. L.; Wilson, R.

    2003-01-01

    Rock, air and service water samples were collected for microbial analyses from 3.2 kilometers depth in a working Au mine in the Witwatersrand basin, South Africa. The approx. 1 meter wide mined zone was comprised of a carbonaceous, quartz, sulfide, uraninite and Au bearing layer, called the Carbon Leader, sandwiched by quartzite and conglomerates. The microbial community in the service water was dominated by mesophilic aerobic and anaerobic, alpha, beta, and gamma-Proteobacteria with a total biomass concentration approx. 10(exp 4) cells/ml, whereas, that of the mine air was dominated by members of the Chlorobi and Bacteroidetes groups and a fungal component. The microorganisms in the Carbon Leader were predominantly mesophilic, aerobic heterotrophic, nitrate reducing and methylotrophic, beta and gamma-Proteobacteria that were more closely related to service water microorganisms rather than air microbes. Rhodamine WT dye and fluorescent microspheres employed as contaminant tracers, however, indicated that service water contamination of most of the rock samples was < 0.01% during acquisition. The microbial contaminants most likely originated from the service water, infiltrated the low permeability rock through and accumulated within mining-induced fractures where they survived for several days prior to being mined. Combined PLFA and terminal restriction fragment length profile (T-RFLP) analyses suggest that the maximum concentration of indigenous microorganisms in the Carbon Leader was < 10(exp 2) cells/g. PLFA, (35)S autoradiography and enrichments suggest that the adjacent quartzite was less contaminated and contained approx. 10(exp 3) cells/gram of a thermophilic, sulfate reducing bacteria, SRB, some of whom are delta Proteobacteria. Pore water and rock geochemical analyses suggest that these SRB's may have been sustained by sulfate diffusing from the adjacent U-rich, Carbon Leader where it was formed by radiolysis of sulfide.

  2. FIELD METHODS TO MEASURE CONTAMINANT REMOVAL EFFECTIVENESS OF GAS-PHASE AIR FILTRATION EQUIPMENT - PHASE 1: SEARCH OF LITERATURE AND PRIOR ART

    Science.gov (United States)

    The report, Phase 1 of a two-phase research project, gives results of a literature search into theeffectiveness of in-field gas-phase air filtration equipment (GPAFE) test methods, including required instrumentation and costs. GPAFE has been used in heating, ventilation, and ...

  3. Dynamics of contamination of an atmospheric air on the database of the network of a radiation control and environment monitoring on the Belarus

    International Nuclear Information System (INIS)

    The system of the radiation control and monitoring of the natural environment which are carried out by Department of hydrometeorology of the Ministry of natural resources and preservation of the environment, includes supervision over pollution of surface waters, bottom sediments, atmospheric air and soil by radionuclides. Supervision is realized at 57 servers, where exposure gamma rate (EDR) is daily measured. The radioactive fallout's from atmospheric air are controlled with use of horizontal plane tables on 30 servers located on all the territory of the Republic. In five towns of Belarus (Minsk, Mogilev, Gomel, Brest, Pinsk) a content of radioactive aerosols in the air is daily measured with the use of the filter-ventilating station In the first period of the catastrophe the levels of exposure gamma rate in Bragin have made - 46000 micro R/h (distance up to Chernobyl NPP - 50 kms), in Chechersk - 10000 micro R/h (distance up to Chernobyl NPP - 180 kms) In June 2002 the maximum single levels were fixed in Bragin - 105 micro R/h and in July in Chechersk - 32 micro R/h. On the rest of the territory the exposure doze rate of gamma - radiation does not exceed the levels of natural gamma - hum noise (up to 20 micro R/h). In regional towns the average annual levels have made from 10 up to 15 micro R/h. The statistical data processing of measurements of exposure gamma rate in 10 most typical the settlements shows, that two groups of the settlements can be selected: with low values EDR up to 20 micro R/h: Lel'chitsy, Mozyr', Slutsk, Mogilev, Pinsk and with values EDR more than 20 micro R/h: Slavgorod, Khojniki, Bragin, Chechersk and Narovlya. The analysis of outcomes of observations behind a state of an atmospheric air has shown, that in 2002 it is not revealed short-lived radionuclides, is not marked of essential changes in behavior cesium-137 and strontium -90 in an atmosphere in comparison with the previous years in post-accident period. Investigation, which are

  4. Contribution to the optimisation of air-breathing combination drives for a hypersonic acceleration mission; Beitrag zur Optimierung luftatmender Kombinationstriebwerke fuer eine Hyperschall-Beschleunigungsmission

    Energy Technology Data Exchange (ETDEWEB)

    Bareis, B.

    1997-11-01

    The work deals with air-breathing combination drives, such as are provided as the first stage drive of a two stage space transport system. A modularly operating drive output calculation process is used for the exact calculation of the drive behaviour, for which the calculation of the forces and the modelling of the drive components is introduced. The dynamic behaviour of the aircraft is calculated by a process of point of flight analysis. By combining the two processes, the important interaction between the behaviour of the drive and the aircraft is taken into account. The purpose of the investigation is a configuration similar to the Saenger space transport system with a drive built up from a turbo jet engine. (orig./AKF) 46 figs., 8 tabs. [Deutsch] Die Arbeit behandelt luftatmende Kombinationstriebwerke, wie sie als Erststufenantrieb eines zweistufigen Raumtransportsystems vorgesehen sind. Zur genauen Berechnung des Triebwerksverhaltens wird ein modular arbeitendes Triebwerksleistungs-Berechnungsverfahren eingesetzt, fuer das die Berechnung des Kraeftehaushalts sowie die Modellierung der Antriebskomponenten vorgestellt werden. Das dynamische Verhalten des Flugzeugs wird mit einem Verfahren zur Flugpunktanalyse berechnet. Durch die Koppelung der beiden Verfahren wird die wichtige Wechselwirkung zwischen Triebwerks- und Flugzeugverhalten beruecksichtigt. Gegenstand der Untersuchungen ist eine dem Raumtransportsystem Saenger angelehnte Konfiguration mit einem aus Turbo-Staustrahl-Triebwerken aufgebauten Antrieb. (orig./AKF)

  5. Flat-floored air-lifted platform: a new method for combining behavior with microscopy or electrophysiology on awake freely moving rodents.

    Science.gov (United States)

    Kislin, Mikhail; Mugantseva, Ekaterina; Molotkov, Dmitry; Kulesskaya, Natalia; Khirug, Stanislav; Kirilkin, Ilya; Pryazhnikov, Evgeny; Kolikova, Julia; Toptunov, Dmytro; Yuryev, Mikhail; Giniatullin, Rashid; Voikar, Vootele; Rivera, Claudio; Rauvala, Heikki; Khiroug, Leonard

    2014-01-01

    It is widely acknowledged that the use of general anesthetics can undermine the relevance of electrophysiological or microscopical data obtained from a living animal's brain. Moreover, the lengthy recovery from anesthesia limits the frequency of repeated recording/imaging episodes in longitudinal studies. Hence, new methods that would allow stable recordings from non-anesthetized behaving mice are expected to advance the fields of cellular and cognitive neurosciences. Existing solutions range from mere physical restraint to more sophisticated approaches, such as linear and spherical treadmills used in combination with computer-generated virtual reality. Here, a novel method is described where a head-fixed mouse can move around an air-lifted mobile homecage and explore its environment under stress-free conditions. This method allows researchers to perform behavioral tests (e.g., learning, habituation or novel object recognition) simultaneously with two-photon microscopic imaging and/or patch-clamp recordings, all combined in a single experiment. This video-article describes the use of the awake animal head fixation device (mobile homecage), demonstrates the procedures of animal habituation, and exemplifies a number of possible applications of the method. PMID:24998224

  6. Experimental evaluation of air distribution in mechanically ventilated residential rooms

    DEFF Research Database (Denmark)

    Tomasi, R.; Krajčík, M.; Simone, A.;

    2013-01-01

    The effect of low ventilation rates (1 or 0.5 air change per hour) on thermal comfort and ventilation effectiveness was experimentally studied in a simulated residential room equipped with radiant floor heating/cooling and mixing ventilation systems. The tests were performed for various positions...... of supply and extract air terminals and different winter and summer boundary conditions. Vertical air temperature, operative temperature and air velocity profiles were measured in different positions in the room, and equivalent temperatures were derived, in order to characterize thermal comfort....... Contaminant removal effectiveness (CRE) and local air change index was measured in order to characterize ventilation effectiveness in the occupied zone. Acceptable thermal comfort was found in most experiments; however, air temperature differences higher than 3 °C occurred when floor cooling was combined with...

  7. Radioactive contamination of the environment

    International Nuclear Information System (INIS)

    The present work opens a series of publications on the results of long-term observations of environmental radioactive contamination in the environs of Leningrad. In the first issue the technique for determination and the results of observations of surface contamination due to artificial radioactive aerosols are presented for 1959-1977. It is shown that the main source of ground air contamination in Leningrad is the global of fission products resulting from nuclear explosions in the atmosphere. The results presented in this work can be used for estimation of levels and isotope composition of radioactive contamination in the temperature zone of the northern hemisphere

  8. Combined microscopies study of the C-contamination induced by extreme-ultraviolet radiation: A surface-dependent secondary-electron-based model

    International Nuclear Information System (INIS)

    SiO2 and Al2O3 surfaces exposed to periodically modulated extreme ultraviolet (EUV) light (λ = 46.9 nm) have been investigated at the μm scale by optical microscopy, scanning electron microscopy, scanning Auger microscopy, atomic force microscopy, and Kelvin probe force microscopy. The formation of a carbon contamination layer preserving the same periodical modulation of the EUV dose has been observed. The mechanisms of hydrocarbon molecules deposition have been studied with the help of correlation plots between the modulated Auger signal and the corresponding EUV dose. A surface-dependent secondary-electron-based model has been proposed.

  9. Combined microscopies study of the C-contamination induced by extreme-ultraviolet radiation: A surface-dependent secondary-electron-based model

    Energy Technology Data Exchange (ETDEWEB)

    Prezioso, S.; Donarelli, M.; Bisti, F.; Palladino, L.; Santucci, S.; Ottaviano, L. [Dip. di Fisica, Universita dell' Aquila, Via Vetoio, 67100 L' Aquila (Italy); Spadoni, S.; Avaro, L. [Micron, Process R and D, Via C. Olivetti 2, 20864 Agrate Brianza (Italy); Liscio, A.; Palermo, V. [CNR-ISOF, Via Gobetti 101, 40129 Bologna (Italy)

    2012-05-14

    SiO{sub 2} and Al{sub 2}O{sub 3} surfaces exposed to periodically modulated extreme ultraviolet (EUV) light ({lambda} = 46.9 nm) have been investigated at the {mu}m scale by optical microscopy, scanning electron microscopy, scanning Auger microscopy, atomic force microscopy, and Kelvin probe force microscopy. The formation of a carbon contamination layer preserving the same periodical modulation of the EUV dose has been observed. The mechanisms of hydrocarbon molecules deposition have been studied with the help of correlation plots between the modulated Auger signal and the corresponding EUV dose. A surface-dependent secondary-electron-based model has been proposed.

  10. Confirmatory research program: effects of atmospheric contaminants on commercial charcoals

    International Nuclear Information System (INIS)

    The increased use of activated charcoals in engineered-safety-feature and normal ventilation systems of nuclear power stations to continually remove radioiodine from flowing air prior to release to the environment has added importance to the question of the effect of atmospheric contaminants on the useful life of the charcoal. In January of 1977 the Naval Research Laboratory (NRL) began an investigation to determine the extent to which atmospheric contaminants in ambient concentrations degrade the efficiency of various commercially-available charcoals for removing methyl iodide. The approach employed by NRL is two-fold. First, charcoal samples are exposed to unmodified outdoor air for periods of one to nine months, then examined for methyl iodide retention, increase in weight, and the pH of water extract. The atmospheric contaminants are identified by the NRL Air Quality Monitoring Station, and concentrations of the various contaminants (ozone, SO2, NO2, CO2, methane and total hydrocarbons) are also available. Second, additional charcoal samples are exposed to the same pollutants under controlled laboratory conditions in various pollutant combinations. Results indicate that the water vapor-charcoal interaction is an important factor in the degradation of the commercial charcoals. Laboratory results indicate the pollutant sulfur dioxide plus water vapor can result in significant charcoal deterioration, as did ozone plus water vapor. Conversely, carbon monoxide did not appear to affect the charcoal. Also, differences were observed for various charcoals

  11. Ammonia oxidizing bacteria and archaea in horizontal flow biofilm reactors treating ammonia-contaminated air at 10 °C.

    Science.gov (United States)

    Gerrity, Seán; Clifford, Eoghan; Kennelly, Colm; Collins, Gavin

    2016-05-01

    The objective of this study was to demonstrate the feasibility of novel, Horizontal Flow Biofilm Reactor (HFBR) technology for the treatment of ammonia (NH3)-contaminated airstreams. Three laboratory-scale HFBRs were used for remediation of an NH3-containing airstream at 10 °C during a 90-d trial to test the efficacy of low-temperature treatment. Average ammonia removal efficiencies of 99.7 % were achieved at maximum loading rates of 4.8 g NH3 m(3) h(-1). Biological nitrification of ammonia to nitrite (NO2 (-)) and nitrate (NO3 (-)) was mediated by nitrifying bacterial and archaeal biofilm populations. Ammonia-oxidising bacteria (AOB) were significantly more abundant than ammonia-oxidising archaea (AOA) vertically at each of seven sampling zones along the vertical HFBRs. Nitrosomonas and Nitrosospira, were the two most dominant bacterial genera detected in the HFBRs, while an uncultured archaeal clone dominated the AOA community. The bacterial community composition across the three HFBRs was highly conserved, although variations occurred between HFBR zones and were driven by physicochemical variables. The study demonstrates the feasibility of HFBRs for the treatment of ammonia-contaminated airstreams at low temperatures; identifies key nitrifying microorganisms driving the removal process; and provides insights for process optimisation and control. The findings are significant for industrial applications of gas oxidation technology in temperate climates. PMID:26879980

  12. ATEMAC - Usage of passive tracer gases for air flow and indoor pollution measurements; ATEMAC - Application des traceurs passifs pour l'etude des mouvements d'air et de contaminants

    Energy Technology Data Exchange (ETDEWEB)

    Roulet, C.-A.

    2001-07-01

    Tracer gases are used in Switzerland for more than 15 years for air flow and ventilation rate measurements as well as for the simulation of air pollutants. The measurement equipment available in Switzerland is accurate and well performing, but rather expensive and voluminous. Moreover, preparing and carrying out the measurements is relatively time consuming. The general objective of the project was the development of a simple, efficient and cheap methodology for the measurement of air flow rates in buildings. Originally, it was thought that a procedure developed at Brookhaven National Laboratory could be transferred to Switzerland. However, measurements at the Swiss Federal Laboratories for Materials Testing and Research (EMPA) indicated that the used tracer gases were adsorbed in an unpredictable way by building materials and pieces of furniture, leading to a massive overestimation of air flow rates. Accordingly, the research work plan was modified in the course of 2000 in order to explore three alternative approaches: (1) the aerosol method, using a photo-ionisation particulate counter; (2) identification and evaluation of new analyzer types; (3) analysis of CO{sub 2} concentration recordings. The conclusions were: (1) the aerosol method is not yet reliable. (2) On the market, a number of analyzers are available at a reasonable price and new devices are currently being developed, especially at the Swiss Federal Institutes of Technology. (3) In numerous cases, the CO{sub 2} concentration methodology is easy to apply, particularly since a computer code for easy interpretation of the concentration measurements was developed and validated. Moreover, the measurements give an estimate of the air-tightness of the building envelope. (author)

  13. Separation of contaminated concrete

    International Nuclear Information System (INIS)

    Separating the contaminated parts from the non-contaminated parts from decommissioned nuclear facilities may strongly reduce the amount of contaminated concrete. The reduction in volume of the radioactive contaminated concrete is dependent on how much cementstone is in the concrete. This research program shows that the radioactive contamination is mostly in the cementstone. However the choice that the cementstone parts, (or better said the radioactive parts) are smaller than 1 mm may not always be true. Normally the cementstone takes about 30% of the total concrete volume. A separation procedure composed by a combination of milling and thermal shock has been assessed. Both the cold and hot thermal shock in combination with milling are not able to separate the cementstone from the larger aggregates completely. However, the cementstone from the concrete with a low nominal grain size seems to be almost completely removed by the combination cold thermal shock/milling, while the cementstone from the concrete with a high nominal grain size seems to be almost completely removed by the combination hot thermal shock/milling. After both methods a layer of cementstone was still visible on the aggregates. Washing followed by a nitric acid treatment removed each 2 wt% of cementstone

  14. Assessment of regularities of ground-level air radionuclide contamination at the Russian coast of the Baltic Sea in the course of the long-term Leningrad Nuclear Power Plant (1983-1999) operation

    International Nuclear Information System (INIS)

    Long-term results of ground-level radionuclide contamination at the Russian coat of the Baltic Sea (nuclear facilities in the vicinity of the town Sosnovy Bor) are under consideration. As compared with 1992-1997, the Leningrad Nuclear Power Plant (NPP) equipment hermetic sealing (in 1998-1999) caused both the reduction of detection frequency of 131I aerosol and the maximum concentrations of 137Cs in the ground-level at the NPP site. Long-term weekly nuclides' concentration time series were examined by correlation analysis. Results of the analysis are presented. The seasonal fluctuations of 7Be concentrations in the ground-level air were examined by the harmonic (Fourier) analysis. The seasonal fluctuations of its concentrations with the maximum in spring-summer period are shown. (author)

  15. The atmospheric distribution of contaminated air masses from the reactors in Fukushima Daiichi - nuclide spectra and dose reduction; Die atmosphaerische Ausbreitung kontaminierter Luftmassen aus den Reaktoren von Fukushima Daiichi - Nuklidspektrum und Dosisrekonstruktion

    Energy Technology Data Exchange (ETDEWEB)

    Zaehringer, Matthias [Bundesamt fuer Strahlenschutz, Freiburg (Germany); Gering, Florian [Bundesamt fuer Strahlenschutz, Oberschleissheim (Germany). Abt. Notfallschutz

    2015-06-01

    The compiled information is based on the data from the United Nations scientific committee on the effects of atomic radiation (UNSCEAR). Due to the earthquake and tsunami only few measurements have been performed during the first days after the reactor accidents in Fukushima Daiichi. In the vicinity of the nuclear power plant no radiation monitoring network comparable to the German IMIS was installed. There are only few data on the air contamination are available. Worldwide in CTBT stations measured activity data of Te-132 and Cs-137 are correlated with estimated data from reactor inventories. It is assumed that the complete rare earth inventories were released - available data of Xe-133 and Kr-85 are analyzed. The UNSCEAR estimation on radiological consequences has to use estimated source terms reconstructed data for the radionuclide migration.

  16. AIR RADIOACTIVITY MONITOR

    Science.gov (United States)

    Bradshaw, R.L.; Thomas, J.W.

    1961-04-11

    The monitor is designed to minimize undesirable background buildup. It consists of an elongated column containing peripheral electrodes in a central portion of the column, and conduits directing an axial flow of radioactively contaminated air through the center of the column and pure air through the annular portion of the column about the electrodes. (AEC)

  17. Fate of polychlorinated biphenyls in a contaminated lake ecosystem: Combining equilibrium passive sampling of sediment and water with total concentration measurements of biota

    DEFF Research Database (Denmark)

    Mäenpää, Kimmo; Leppänen, Matti T.; Figueiredo, Kaisa;

    2015-01-01

    hydrophobic organic chemicals in biota lipids. The authors' aim was to assess the equilibrium status of polychlorinated biphenyls (PCBs) in a contaminated lake ecosystem and along its discharge course using equilibrium sampling devices for measurements in sediment and water and by also analyzing biota. The...... authors used equilibrium sampling devices (silicone rubber and polyethylene [PE]) to determine freely dissolved concentrations and chemical activities of PCBs in the water column and sediment porewater and calculated for both phases the corresponding equilibrium concentrations and chemical activities in...... model lipids. Overall, the studied ecosystem appeared to be in disequilibrium for the studied phases: sediment, water, and biota. Chemical activities of PCBs were higher in sediment than in water, which implies that the sediment functioned as a partitioning source of PCBs and that net diffusion occurred...

  18. Fate of polychlorinated biphenyls in a contaminated lake ecosystem: combining equilibrium passive sampling of sediment and water with total concentration measurements of biota.

    Science.gov (United States)

    Mäenpää, Kimmo; Leppänen, Matti T; Figueiredo, Kaisa; Mayer, Philipp; Gilbert, Dorothea; Jahnke, Annika; Gil-Allué, Carmen; Akkanen, Jarkko; Nybom, Inna; Herve, Sirpa

    2015-11-01

    Equilibrium sampling devices can be applied to study and monitor the exposure and fate of hydrophobic organic chemicals on a thermodynamic basis. They can be used to determine freely dissolved concentrations and chemical activity ratios and to predict equilibrium partitioning concentrations of hydrophobic organic chemicals in biota lipids. The authors' aim was to assess the equilibrium status of polychlorinated biphenyls (PCBs) in a contaminated lake ecosystem and along its discharge course using equilibrium sampling devices for measurements in sediment and water and by also analyzing biota. The authors used equilibrium sampling devices (silicone rubber and polyethylene [PE]) to determine freely dissolved concentrations and chemical activities of PCBs in the water column and sediment porewater and calculated for both phases the corresponding equilibrium concentrations and chemical activities in model lipids. Overall, the studied ecosystem appeared to be in disequilibrium for the studied phases: sediment, water, and biota. Chemical activities of PCBs were higher in sediment than in water, which implies that the sediment functioned as a partitioning source of PCBs and that net diffusion occurred from the sediment to the water column. Measured lipid-normalized PCB concentrations in biota were generally below equilibrium lipid concentrations relative to the sediment (CLip ⇌Sed ) or water (CLip ⇌W ), indicating that PCB levels in the organisms were below the maximum partitioning levels. The present study shows the application versatility of equilibrium sampling devices in the field and facilitates a thermodynamic understanding of exposure and fate of PCBs in a contaminated lake and its discharge course. PMID:26053463

  19. A Study of the Combined Effects of Physical Activity and Air Pollution on Mortality in Elderly Urban Residents: The Danish Diet, Cancer, and Health Cohort

    OpenAIRE

    Andersen, Zorana Jovanovic; de Nazelle, Audrey; Mendez, Michelle Ann; Garcia-Aymerich, Judith; Hertel, Ole; Tjønneland, Anne; Overvad, Kim; Raaschou-Nielsen, Ole; Nieuwenhuijsen, Mark J.

    2015-01-01

    Background Physical activity reduces, whereas exposure to air pollution increases, the risk of premature mortality. Physical activity amplifies respiratory uptake and deposition of air pollutants in the lung, which may augment acute harmful effects of air pollution during exercise. Objectives We aimed to examine whether benefits of physical activity on mortality are moderated by long-term exposure to high air pollution levels in an urban setting. Methods A total of 52,061 subjects (50–65 year...

  20. Avaliação da intensidade de contaminação de pontas de seringa tríplice Evaluation of the bacterial contamination of air/water syringes tips

    Directory of Open Access Journals (Sweden)

    Eliza Maria Agueda RUSSO

    2000-09-01

    Full Text Available O controle de infecção cruzada em consultórios odontológicos inclui cuidados especiais com as seringas tríplices. Os autores pesquisaram a intensidade de contaminação pela microbiota bucal, de pontas de seringas tríplices usadas no atendimento a pacientes de Dentística Restauradora. Cinqüenta pontas descartáveis (Riskcontrol, Injecta Prod. Odontológicos foram avaliadas: 10, imediatamente após a abertura da embalagem; 30, após o uso em pacientes; e 10, após o uso e a desinfecção com álcool etílico 70% P/V, friccionado por um minuto. Em câmara de fluxo laminar, as pontas foram "roladas" sobre a superfície de Tryptic Soy Agar, suplementado com 5% de sangue desfibrinado de carneiro. Após 96 horas de incubação anaeróbia, foi feita a avaliação da quantidade de unidades formadoras de colônias (ufc desenvolvidas. Confirmando a informação do fabricante, as pontas estavam estéreis quando retiradas da embalagem. Em todas as pontas usadas em pacientes, observou-se um número incontável de ufc (maior que 300, revelando intensa contaminação. Nas pontas usadas e desinfetadas com álcool etílico 70% P/V, verificou-se apreciável redução na contagem de colônias (1 a 100 ufc, mas incompatível com a segurança biológica. Os resultados sugerem, como condição ideal, o uso de pontas descartáveis nas seringas tríplices.Effective infection control procedures to prevent cross-contamination in the dental office include care with air/water syringes. The authors had the purpose to verify the bacterial contamination of air/water syringes used in patients seen at the Restorative Dental Clinic, School of Dentistry, University of São Paulo, Brazil. Fifty disposable tips (Riskcontrol, Injecta Prod. Odontológicos were analysed: 10, immediately after the package was opened; 10, after a single use followed by disinfection with 70% alcohol for one minute; 30, after a single use without any posterior disinfection. The samples were

  1. PREDICTION OF GAS HOLD-UP IN A COMBINED LOOP AIR LIFT FLUIDIZED BED REACTOR USING NEWTONIAN AND NON-NEWTONIAN LIQUIDS

    Directory of Open Access Journals (Sweden)

    Sivakumar Venkatachalam

    2011-09-01

    Full Text Available Many experiments have been conducted to study the hydrodynamic characteristics of column reactors and loop reactors. In this present work, a novel combined loop airlift fluidized bed reactor was developed to study the effect of superficial gas and liquid velocities, particle diameter, fluid properties on gas holdup by using Newtonian and non-Newtonian liquids. Compressed air was used as gas phase. Water, 5% n-butanol, various concentrations of glycerol (60 and 80% were used as Newtonian liquids, and different concentrations of carboxy methyl cellulose aqueous solutions (0.25, 0.6 and 1.0% were used as non-Newtonian liquids. Different sizes of spheres, Bearl saddles and Raschig rings were used as solid phases. From the experimental results, it was found that the increase in superficial gas velocity increases the gas holdup, but it decreases with increase in superficial liquid velocity and viscosity of liquids. Based on the experimental results a correlation was developed to predict the gas hold-up for Newtonian and non-Newtonian liquids for a wide range of operating conditions at a homogeneous flow regime where the superficial gas velocity is approximately less than 5 cm/s

  2. Combined effect of synthetic protein, Mini-B, and cholesterol on a model lung surfactant mixture at the air-water interface.

    Science.gov (United States)

    Chakraborty, Aishik; Hui, Erica; Waring, Alan J; Dhar, Prajnaparamita

    2016-04-01

    The overall goal of this work is to study the combined effects of Mini-B, a 34 residue synthetic analog of the lung surfactant protein SP-B, and cholesterol, a neutral lipid, on a model binary lipid mixture containing dipalmitolphosphatidylcholine (DPPC) and palmitoyl-oleoyl-phosphatidylglycerol (POPG), that is often used to mimic the primary phospholipid composition of lung surfactants. Using surface pressure vs. mean molecular area isotherms, fluorescence imaging and analysis of lipid domain size distributions; we report on changes in the structure, function and stability of the model lipid-protein films in the presence and absence of varying composition of cholesterol. Our results indicate that at low cholesterol concentrations, Mini-B can prevent cholesterol's tendency to lower the line tension between lipid domain boundaries, while maintaining Mini-B's ability to cause reversible collapse resulting in the formation of surface associated reservoirs. Our results also show that lowering the line tension between domains can adversely impact monolayer folding mechanisms. We propose that small amounts of cholesterol and synthetic protein Mini-B can together achieve the seemingly opposing requirements of efficient LS: fluid enough to flow at the air-water interface, while being rigid enough to oppose irreversible collapse at ultra-low surface tensions. PMID:26775740

  3. Ambient air monitoring for organic compounds, acids, and metals at Los Alamos National Laboratory, January 1991

    International Nuclear Information System (INIS)

    Los Alamos National Laboratory (LANL) contracted Radian Corporation (Radian) to conduct a short-term, intensive air monitoring program whose goal was to estimate the impact of chemical emissions from LANL on the ambient air environment. A comprehensive emission inventory had identified more than 600 potential air contaminants in LANL's emissions. A subset of specific target chemicals was selected for monitoring: 20 organic vapors, 6 metals and 5 inorganic acid vapors. These were measured at 5 ground level sampling sites around LANL over seven consecutive days in January 1991. The sampling and analytical strategy used a combination of EPA and NIOSH methods modified for ambient air applications

  4. Growth and cesium uptake responses of Phytolacca americana Linn. and Amaranthus cruentus L. grown on cesium contaminated soil to elevated CO2 or inoculation with a plant growth promoting rhizobacterium Burkholderia sp. D54, or in combination

    International Nuclear Information System (INIS)

    Highlights: ► Elevated CO2 and microbial inoculation, alone or in combination, significantly promoted growth of P. americana, and A. cruentus. ► Total tissue Cs in plants was significantly increased. ► A. cruentus had higher tissue Cs concentration, Cs transfer factors and concentration ratios than P. americana. ► The two plants had slightly different contents of antioxidant enzymes. ► Combined effects of elevated CO2 and microbial inoculation can be explored for CO2- and microbe-assisted phytoextraction technology. - Abstract: Growth and cesium uptake responses of plants to elevated CO2 and microbial inoculation, alone or in combination, can be explored for clean-up of contaminated soils, and this induced phytoextraction may be better than the natural process. The present study used open-top chambers to investigate combined effects of Burkholderia sp. D54 inoculation and elevated CO2 (860 μL L−1) on growth and Cs uptake by Phytolacca americana and Amaranthus cruentus grown on soil spiked with various levels of Cs (0–1000 mg kg−1). Elevated CO2 and bacterial inoculation, alone or in combination, significantly increased biomass production with increased magnitude, ranging from 22% to 139% for P. americana, and 14% to 254% for A. cruentus. Total tissue Cs in both plants was significantly greater for bacterial inoculation treatment singly, and combined treatments of bacterial inoculation and elevated CO2 than for the control treatment in most cases. Regardless of CO2 concentrations and bacterial inoculation, A. cruentus had higher tissue Cs concentration, Cs transfer factors and concentration ratios than P. americana, but they had slightly different contents of antioxidant enzymes. It is concluded that combined effects of elevated CO2 and microbial inoculation with regard to plant ability to grow and remove radionuclides from soil can be explored for CO2- and microbe-assisted phytoextraction technology.

  5. Bioleaching of heavy metals from contaminated sediment by indigenous sulfur-oxidizing bacteria in an air-lift bioreactor: effects of sulfur concentration.

    Science.gov (United States)

    Chen, Shen-Yi; Lin, Jih-Gaw

    2004-01-01

    The effects of sulfur concentration on the bioleaching of heavy metals from the sediment by indigenous sulfur-oxidizing bacteria were investigated in an air-lift reactor. Increasing the sulfur concentration from 0.5 to 5 g/l enhanced the rates of pH reduction, sulfate production and metal solubilization. A Michaelis-Menten type equation was used to explain the relationships between sulfur concentration, sulfate production and metal solubilization in the bioleaching process. After 8 days of bioleaching, 97-99% of Cu, 96-98% of Zn, 62-68% of Mn, 73-87% of Ni and 31-50% of Pb were solubilized from the sediment, respectively. The efficiency of metal solubilization was found to be related to the speciation of metal in the sediment. From economical consideration, the recommended sulfur dosage for the bioleaching of metals from the sediment is 3g/l. PMID:15276736

  6. Assessment of the contribution of the Koshkar-Ata tailing dumps in contamination by radionuclides and heavy metals of ambient air in the area of Aktau city

    International Nuclear Information System (INIS)

    The paper presents data on concentrations of toxic metals and radionuclides in air particulate samples collected at settlements nearby Koshkar-Ata tailing dumps. The data are from a larger study designed to provide a scientific basis for the development of a rehabilitation measures policy on tailing facilities of uranium industry bearing a potential hazard to local inhabitants. Aerosol samples were collected on filters in mobile monitoring posts at nearest settlements around the tailing dumps (12 samples). Deposited atmospheric pollutants (DAPs) were collected on special pads set on stationary posts in the vicinity of Koshkar-Ata (66 samples). The analytical techniques used were for radionuclide and toxic constituent determination were, inductively coupled plasma mass spectrometry (ICP-MS) as well as gamma spectrometry with high sensitivity and pure Ge detector, respectively. (author)

  7. Linking air and water transport in intact soils to macro-porosity by combining laboratory measurements and X-ray Computed Tomography

    DEFF Research Database (Denmark)

    Katuwal, Sheela; Norgaard, Trine; Møldrup, Per;

    With an objective to link the hydraulic properties of soil with the soil structural properties, air permeability and 5% arrival time of a conservative tracer was measured for large undisturbed soil columns from the same agricultural field. The same soil columns were scanned with a medical scanner......-porosity (R2 = 0.80 for air permeability: R2= 0.61 for 5% arrival time) and macro-porosity of the restricting layer (R2=0.83 for air permeability: R2= 0.71 for 5% arrival time) over air-filled porosity and all the correlations were positive. The high positive correlation these air and water transport...... functions with macro-porosity stressed the importance of continuity and tortuosity of pores in air, water and solute flow and transport through the soils. Negative correlations of air permeability, 5% arrival time of tracer and macro-porosity were obtained with bulk density whereas with other soil physical...

  8. Effect of Remediation Parameters on in-Air Ambient Dose Equivalent Rates When Remediating Open Sites with Radiocesium-contaminated Soil.

    Science.gov (United States)

    Malins, Alex; Kurikami, Hiroshi; Kitamura, Akihiro; Machida, Masahiko

    2016-10-01

    Calculations are reported for ambient dose equivalent rates [H˙*(10)] at 1 m height above the ground surface before and after remediating radiocesium-contaminated soil at wide and open sites. The results establish how the change in H˙*(10) upon remediation depends on the initial depth distribution of radiocesium within the ground, on the size of the remediated area, and on the mass per unit area of remediated soil. The remediation strategies considered were topsoil removal (with and without recovering with a clean soil layer), interchanging a topsoil layer with a subsoil layer, and in situ mixing of the topsoil. The results show the ratio of the radiocesium components of H˙*(10) post-remediation relative to their initial values (residual dose factors). It is possible to use the residual dose factors to gauge absolute changes in H˙*(10) upon remediation. The dependency of the residual dose factors on the number of years elapsed after fallout deposition is analyzed when remediation parameters remain fixed and radiocesium undergoes typical downward migration within the soil column. PMID:27575348

  9. Characterization of chlorinated solvent contamination in limestone using innovative FLUTe® technologies in combination with other methods in a line of evidence approach

    DEFF Research Database (Denmark)

    Broholm, Mette Martina; Janniche, Gry Sander; Mosthaf, Klaus;

    2016-01-01

    Characterization of dense non-aqueous phase liquid (DNAPL) source zones in limestone aquifers/bedrock is essential to develop accurate site-specific conceptual models and perform risk assessment. Here innovative field methods were combined to improve determination of source zone architecture...

  10. Indoor air pollution

    International Nuclear Information System (INIS)

    Although official efforts to control air pollution have traditionally focused on outdoor air, it is now apparent that elevated contaminant concentrations are common inside some private and public buildings. Concerns about potential public health problems due to indoor air pollution are based on evidence that urban residents typically spend more than 90 percent of their time indoors, concentrations of some contaminants are higher indoors than outdoors, and for some pollutants personal exposures are not characterized adequately by outdoor measurements. Among the more important indoor contaminants associated with health or irritation effects are passive tobacco smoke, radon decay products, carbon monoxide, nitrogen dioxide, formaldehyde, asbestos fibers, microorganisms and aeroallergens. Efforts to assess health risks associated with indoor air pollution are limited by insufficient information about the number of people exposed, the pattern and severity of exposures, and the health consequences of exposures. An overall strategy should be developed to investigate indoor exposures, health effects, control options, and public policy alternatives

  11. On the use of a freeze-dried versus an air-dried soil humic acid as a surrogate of soil organic matter for contaminant sorption

    International Nuclear Information System (INIS)

    The sorption of phenanthrene (PHN) to relatively pure soil humic acids (HAs) was investigated to assess the suitability of the soil HA as a surrogate sorbent for the soil organic matter (SOM). The HAs were prepared in both freeze-dried and air-dried forms. The two forms of HAs from the same source are similar in composition but the freeze-dried HAs exhibit a significantly higher initial surface area (SA) (3.86–4.59 m2/g); the SAs of air-dried HAs are below 0.1 m2/g. However, the SAs of freeze-dried HAs are not stable upon contact with water; the samples lose practically all the SA after 4 days of immersion in water. The PHN sorption to both forms of HAs is practically linear, whether a co-solute is present or not. The sorption linearity observed with the present freeze-dried HAs is in sharp contrast with the allegedly nonlinear PHN sorption on similar freeze-dried HAs as presented by others. - Highlights: ► In contrast to the alleged nonlinear sorption of a nonpolar organic pollutant to a freeze-dried humic acid (HA) from water. ► This study shows no evidence for such nonlinearity. ► The initially prepared freeze-dried HA exhibits a significant surface area. ► This artificially created surface area is however unstable upon contact with water. - This study shows no alleged nonlinear sorption of a nonpolar organic pollutant from water to solid humic acids extracted from soils.

  12. Comparing a combination of penicillin G and gentamicin to a combination of clindamycin and amikacin as prophylactic antibiotic regimens in prevention of clean contaminated wound infections in cancer surgery

    International Nuclear Information System (INIS)

    Background and aim: Appropriate antibiotic selection and timing of administration for prophylaxis are crucial to reduce the likelihood of surgical site infection (SSI) after a clean contaminated cancer surgery. Our aim is to compare the use of two prophylactic antibiotic (PA) regimens as regards efficacy, timing, and cost. Patients and methods: Two hundred patients with gastric, bladder, or colorectal cancer were randomized to receive preoperative PA, group A received penicillin G sodium and gentamicin and group B received clindamycin and amikacin intravenously. The demographic data of patients were collected, and they were observed for wound infections. Results: Infected wounds occurred in 19 patients with a rate of 9.5%. Highest incidence of SSI was among bladder cancer patients (14.2%); p = 0.044. The rate of SSI was 11 % in group A, and 8% in group B, p = 0.469. The cost of PA administered in group A was significantly less than that of group B (21.96 ± 3.22 LE versus 117.05 ± 12.74 LE, respectively; p < 0.001). SSI tended to be higher among those who had longer time for antibiotic and incision (≥ 30 min) than those who had shorter time interval (<30 min), (13% vs. 6.5%, respectively). Conclusion: Both penicillin + gentamicin and clindamycin + amikacin are safe and effective for the prevention of SSI in clean contaminated operative procedures. In a resource limited hospital, a regimen including penicillin + gentamicin is a cost-effective alternative for the more expensive and broader coverage of clindamycin + amikacin. Timing of PA is effective in preventing SSIs when administered 30 min before the start of surgery

  13. Detecting a wide range of environmental contaminants in human blood samples--combining QuEChERS with LC-MS and GC-MS methods.

    Science.gov (United States)

    Plassmann, Merle M; Schmidt, Magdalena; Brack, Werner; Krauss, Martin

    2015-09-01

    Exposure to environmental pollution and consumer products may result in an uptake of chemicals into human tissues. Several studies have reported the presence of diverse environmental contaminants in human blood samples. However, previously developed multi-target methods for the analysis of human blood include a fairly limited amount of compounds stemming from one or two related compound groups. Thus, the sample preparation method QuEChERS (quick easy cheap effective rugged and safe) was tested for the extraction of 64 analytes covering a broad compound domain followed by detection using liquid and gas chromatography coupled to mass spectrometry (LC- and GC-MS). Forty-seven analytes showed absolute recoveries above 70% in the first QuEChERS step, being a simple liquid-liquid extraction (LLE) using acetonitrile and salt. The second QuEChERS step, being a dispersive solid phase extraction, did not result in an overall improvement of recoveries or removal of background signals. Using solely the LLE step, eight analytes could subsequently be detected in human blood samples from the German Environmental Specimen Bank. Using a LC-multiple reaction monitoring (MRM) method with a triple quadrupole instrument, better recoveries were achieved than with an older LC-high-resolution (HR) MS full scan orbitrap instrument, which required a higher concentration factor of the extracts. However, the application of HRMS full scan methods could be used for the detection of additional compounds retrospectively. PMID:26206704

  14. A Breath of Fresh Air: Addressing Indoor Air Quality

    Science.gov (United States)

    Palliser, Janna

    2011-01-01

    Indoor air pollution refers to "chemical, biological, and physical contamination of indoor air," which may result in adverse health effects (OECD 2003). The causes, sources, and types of indoor air pollutants will be addressed in this article, as well as health effects and how to reduce exposure. Learning more about potential pollutants in home…

  15. Predictive Techniques for Spacecraft Cabin Air Quality Control

    Science.gov (United States)

    Perry, J. L.; Cromes, Scott D. (Technical Monitor)

    2001-01-01

    As assembly of the International Space Station (ISS) proceeds, predictive techniques are used to determine the best approach for handling a variety of cabin air quality challenges. These techniques use equipment offgassing data collected from each ISS module before flight to characterize the trace chemical contaminant load. Combined with crew metabolic loads, these data serve as input to a predictive model for assessing the capability of the onboard atmosphere revitalization systems to handle the overall trace contaminant load as station assembly progresses. The techniques for predicting in-flight air quality are summarized along with results from early ISS mission analyses. Results from groundbased analyses of in-flight air quality samples are compared to the predictions to demonstrate the technique's relative conservatism.

  16. Contamination by mercury in air of the mining district of San Martin de Loba in Bolivar's Department, Colombia; Contaminacion por mercurio en aire del distrito minero de San Martin de loba en el Departamento de Bolivar, Colombia

    Energy Technology Data Exchange (ETDEWEB)

    Olivero V, J.; Young C, F.; Caballero G, K., E-mail: jolivero@unicartagena.edu.co [Universidad de Cartagena, Facultad de Ciencias Farmaceuticas, Grupo de Quimica Ambiental y Computacional, Calle de la Universidad 36-100, Cartagena de Indias (Colombia)

    2014-06-01

    Mercury (Hg) is a heavy metal, considered a highly toxic pollutant. In its elemental state is volatile, making it easy to transport over long distances through the atmosphere, so that environmental pollution caused by it is a serious problem worldwide. Activities such as gold mining, where metallic Hg is used, have contributed with its global distribution, affecting ecosystems and human health. The aim of this study was to determine the levels of total mercury (T-Hg) in air in gold mining areas in Southern Bolivar, particularly in the mining district of San Martin de Loba, in the municipalities of San Martin de Loba and Barranco de Loba (Mina Santa Cruz), Colombia. In situ analyses were performed by atomic absorption spectroscopy, using a portable Ra-915 + Zeeman mercury analyzer. In Mina Santa Cruz, one of the most important gold mines in Colombia, concentrations of Hg in air ranged between 163.7 ± 6.6 and 40 455 ± 2154 mg/m{sup 3}, while in the urban area of San Martin de Loba varied from 223.6 ± 20.8 to 27 140 ± 212.5 ng/m{sup 3}. In those places where an amalgam burning process was taking place at the time of the measurements, Hg concentrations reached values of 40 455 ± 2154 ng/m{sup 3}. These data imply a severe occupational exposure to Hg for operators and citizens living in cities located near mines. Therefore, it is important to regulate and control the use of Hg in gold mining, avoiding a chronic impact of the metal on the health of people and the environment. (author)

  17. Bacterial contamination of radiopharmaceutical preparations

    International Nuclear Information System (INIS)

    Examinations of the microflora of the air, personnel hands' skin, and surface of the equipment were performed in the Centre for Nuclear research, Libya. It is stated that bacterial contamination was maximal in winter and minimal in summer. The authors believe that human factor is the crucial in bacterial contamination. The microflora detected at the surfaces of equipment contains increased levels of radioresistent forms of bacteria. 8 refs.; 3 tabs

  18. Contaminated sites

    International Nuclear Information System (INIS)

    The term 'Contaminated sites' refers to soil and groundwater contamination caused by local sources such as landfills or industrial sites. As of July 2002, there were in Austria 2,372 sites registered as potentially contaminated sites, from them: 165 sites required remediation, for 55 sites non remedial measures were necessary and to date 65 sites were remediated with a cost of 700,000 M Euro. An overview about funding of remedial measures, estimation of the extent of the problem (remediation requirements, chlorinated hydrocarbons accidents), deficits (lack of legal harmonization, slow implementation of remedial measures, etc.) is presented. Table 1. (nevyjel)

  19. Characteristics, Control and Remediation of Soil Contaminated with Combined Pollution from a Solid Waste Dismantling Area%固废拆解土壤的复合污染特性及其控制与修复

    Institute of Scientific and Technical Information of China (English)

    于红艳; 张昕欣; 杨伟群; 陈红云; 杨雪雪; 朱梦琪

    2012-01-01

    The dismantling of solid waste has resulted in severe contamination of toxic heavy metals, persistant organic pollutant( POPs) , pol-ycyclic aromatic hydrocarbons (PAHs) , polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and polybrominated diphenyl ethers (PBDEs) for soil in these areas. The methods of control of soil pollutants and remediation of contaminated soil were put forward in the basis of analysis of pollutants environmental behavior in the soil and its migration and transformation laws, which to provide a reliable basis for green dismantling industry and provide reference for remediation of soil contaminated with combined pollution from a solid waste dismantling area.%固废拆解造成了包括重金属、持久性有机污染物(POPs)[多环芳烃(PAHs)、多氯联苯(PCBs)、二噁英(PCDD/Fs)及多溴联苯醚(PBDEs)]的土壤复合污染.探讨了固废拆解土壤的污染源及污染现状,分析了复合污染物在土壤中的环境行为及迁移转化规律,提出了控制土壤污染物对策及污染土壤修复方法,旨在为发展绿色拆解产业提供可靠的依据,为固废拆解导致的土壤污染控制与修复提供参考.

  20. Air movement and perceived air quality

    DEFF Research Database (Denmark)

    Melikov, Arsen Krikor; Kaczmarczyk, J.

    2012-01-01

    The impact of air movement on perceived air quality (PAQ) and sick building syndrome (SBS) symptoms was studied. In total, 124 human subjects participated in four series of experiments performed in climate chambers at different combinations of room air temperature (20, 23, 26 and 28 °C), relative...... humidity (30, 40 and 70%) and pollution level (low and high). Most of the experiments were performed with and without facially applied airflow at elevated velocity. The importance of the use of recirculated room air and clean, cool and dry outdoor air was studied. The exposures ranged from 60. min to 235....... min. Acceptability of PAQ and freshness of the air improved when air movement was applied. The elevated air movement diminished the negative impact of increased air temperature, relative humidity and pollution level on PAQ. The degree of improvement depended on the pollution level, the temperature and...