Sample records for respirable suspended particulates

  1. Identifying anthropogenic and natural influences on extreme pollution of respirable suspended particulates in Beijing using backward trajectory analysis.

    Song, Yu; Miao, Weijie; Liu, Bing; Dai, Wei; Cai, Xuhui


    In China, daily respirable suspended particulate (RSP, particles with aerodynamic diameters less than 10 microm) concentrations exceeding 420 microg m(-3) are considered "hazardous" to health. These can lead to the premature onset of certain diseases and premature death of sick and elderly people; even healthy people are warned to avoid outdoor activity when RSP concentrations are high. Such high pollution levels are defined as extreme RSP pollution events. Recent epidemiological studies have shown that a distinct difference exists between the health effects caused by natural sources and anthropogenic sources, mandating knowledge of the source of extreme RSP pollution. Twenty-six extreme RSP pollution events were recorded in Beijing from January 2003 to December 2006. The HYSPLIT4 (Hybrid Single Particle Lagrangian Integrated Trajectory) model (Version 4) was used to discriminate the sources of these extreme RSP pollution events. The model found that twelve events were caused from natural sources (dust storms), nine events from anthropogenic sources (e.g., vehicles and industrial activities, etc.) under quasi-quiescent weather, and five events were from mixed causes. Identifying such events will be valuable in epidemiological studies on air pollution in Beijing.

  2. Effectiveness of dust control methods for crystalline silica and respirable suspended particulate matter exposure during manual concrete surface grinding.

    Akbar-Khanzadeh, Farhang; Milz, Sheryl A; Wagner, Cynthia D; Bisesi, Michael S; Ames, April L; Khuder, Sadik; Susi, Pam; Akbar-Khanzadeh, Mahboubeh


    Concrete grinding exposes workers to unacceptable levels of crystalline silica dust, known to cause diseases such as silicosis and possibly lung cancer. This study examined the influence of major factors of exposure and effectiveness of existing dust control methods by simulating field concrete grinding in an enclosed workplace laboratory. Air was monitored during 201 concrete grinding sessions while using a variety of grinders, accessories, and existing dust control methods, including general ventilation (GV), local exhaust ventilation (LEV), and wet grinding. Task-specific geometric mean (GM) of respirable crystalline silica dust concentrations (mg/m³ for LEV:HEPA-, LEV:Shop-vac-, wet-, and uncontrolled-grinding, while GV was off/on, were 0.17/0.09, 0.57/0.13, 1.11/0.44, and 23.1/6.80, respectively. Silica dust concentrations (mg/m³ using 100-125 mm (4-5 inch) and 180 mm (7 inch) grinding cups were 0.53/0.22 and 2.43/0.56, respectively. GM concentrations of silica dust were significantly lower for (1) GV on (66.0%) vs. off, and (2) LEV:HEPA- (99.0%), LEV:Shop-vac- (98.1%) or wet- (94.4%) vs. uncontrolled-grinding. Task-specific GM of respirable suspended particulate matter (RSP) concentrations (mg/m³ for LEV:HEPA-, LEV:Shop-vac-, wet-, and uncontrolled grinding, while GV was off/on, were 1.58/0.63, 7.20/1.15, 9.52/4.13, and 152/47.8, respectively. GM concentrations of RSP using 100-125 mm and 180 mm grinding cups were 4.78/1.62 and 22.2/5.06, respectively. GM concentrations of RSP were significantly lower for (1) GV on (70.2%) vs. off, and (2) LEV:HEPA- (98.9%), LEV:Shop-vac- (96.9%) or wet- (92.6%) vs. uncontrolled grinding. Silica dust and RSP were not significantly affected by (1) orientation of grinding surfaces (vertical vs. inclined); (2) water flow rates for wet grinding; (3) length of task-specific sampling time; or, (4) among cup sizes of 100, 115 or 125 mm. No combination of factors or control methods reduced an 8-hr exposure level to below the

  3. Chemical speciation of respirable suspended particulate matter during a major firework festival in India.

    Sarkar, Sayantan; Khillare, Pandit S; Jyethi, Darpa S; Hasan, Amreen; Parween, Musarrat


    Ambient respirable particles (PM ≤ 10 μm, denoted by PM(10)) were characterized with respect to 20 elements, 16 polycyclic aromatic hydrocarbons (PAHs), elemental and organic carbon (EC and OC) during a major firework event-the "Diwali" festival in Delhi, India. The event recorded extremely high 24-h PM(10) levels (317.2-616.8 μg m(-3), 6-12 times the WHO standard) and massive loadings of Ba (16.8 μg m(-3), mean value), K (46.8 μg m(-3)), Mg (21.3 μg m(-3)), Al (38.4 μg m(-3)) and EC (40.5 μg m(-3)). Elemental concentrations as high as these have not been reported previously for any firework episode. Concentrations of Ba, K, Sr, Mg, Na, S, Al, Cl, Mn, Ca and EC were higher by factors of 264, 18, 15, 5.8, 5, 4, 3.2, 3, 2.7, 1.6 and 4.3, respectively, on Diwali as compared to background values. It was estimated that firework aerosol contributed 23-33% to ambient PM(10) on Diwali. OC levels peaked in the post-Diwali samples, perhaps owing to secondary transformation processes. Atmospheric PAHs were not sourced from fireworks; instead, they correlated well with changes in traffic patterns indicating their primary source in vehicular emissions. Overall, the pollutant cocktail generated by the Diwali fireworks could be best represented with Ba, K and Sr as tracers. It was also found that chronic exposure to Diwali pollution is likely to cause at least a 2% increase in non-carcinogenic hazard index (HI) associated with Al, Mn and Ba in the exposed population. Copyright © 2010 Elsevier B.V. All rights reserved.

  4. Geochemical Investigations of Respirable Particulate Matter

    Jurinski, Joseph Bernard Jr.


    GEOCHEMICAL INVESTIGATIONS OF RESPIRABLE PARTICULATE MATTER Joseph Bernard Jurinski (Abstract) Over the course of our lives we are exposed to airborne particulate matter in the workplace, home, and environment that results in the deposition of millions of particles in the lung. These exposures may result in disease if they are significant enough. The potential for harmful exposure depends in part on the dust's biodurability and the bioavailability of harmful constituents d...

  5. Spatial distribution of respirable and inhalable particulate matter concentration in sawmills of South-South Region of Nigeria

    T.F. Ediagbonya


    Full Text Available Dust particles in the air that can be respired into the nose or mouth during normal breathing are known as inhalable particle. Inhalation decreases gradually with increasing particle diameter. The respirable and inhalable sawdust were collected from nine different sawmills in Benin City from November 2009 to February 2010 using portable programmable SKC Air Check XR5000 High Volume Gravimetric Sampler Model 210-5000 Serial No. 20537 and I.O.M (Institute Occupational Medicine Edinburg Multi dust sampler, Batch No. 221442/1. The objective of this study is to know the concentration of inhalable suspended particulate matter fraction and the respirable suspended particulate matter fraction in sawmill particulate. The mean concentration range of the respirable suspended particulate matter was 173.61-520.83 g/m3 and the inhalable suspended particulate matter was in a range of 555.56-2,013.98 g/m3. A strong positive correlation existed for inhalable suspended particulate matter and respirable suspended particulate matter. And the spatial variation was significant and remarkable.

  6. 42 CFR 84.170 - Non-powered air-purifying particulate respirators; description.


    ... 42 Public Health 1 2010-10-01 2010-10-01 false Non-powered air-purifying particulate respirators... DEVICES Non-Powered Air-Purifying Particulate Respirators § 84.170 Non-powered air-purifying particulate respirators; description. (a) Non-powered air-purifying particulate respirators utilize the wearer's...

  7. 23 Elemental Composition of Suspended Particulate Matter ...


    coarse and fine particulate matter fractions at the higher height. The elements Cu, Zn, ... dense population, high density housing, the ..... could be in the vapor phase at the higher height. .... precipitation from a remote background site in. India.

  8. 42 CFR 84.179 - Non-powered air-purifying particulate respirators; filter identification.


    ... 42 Public Health 1 2010-10-01 2010-10-01 false Non-powered air-purifying particulate respirators... RESPIRATORY PROTECTIVE DEVICES Non-Powered Air-Purifying Particulate Respirators § 84.179 Non-powered air-purifying particulate respirators; filter identification. (a) The respirator manufacturer, as part of...

  9. 42 CFR 84.171 - Non-powered air-purifying particulate respirators; required components.


    ... 42 Public Health 1 2010-10-01 2010-10-01 false Non-powered air-purifying particulate respirators... PROTECTIVE DEVICES Non-Powered Air-Purifying Particulate Respirators § 84.171 Non-powered air-purifying particulate respirators; required components. (a) Each non-powered air-purifying particulate...

  10. 42 CFR 84.206 - Particulate tests; respirators with filters; minimum requirements; general.


    ... 42 Public Health 1 2010-10-01 2010-10-01 false Particulate tests; respirators with filters... RESPIRATORY PROTECTIVE DEVICES Chemical Cartridge Respirators § 84.206 Particulate tests; respirators with filters; minimum requirements; general. (a) Three respirators with cartridges containing, or...

  11. Efficiency of Respirator Filter Media against Diesel Particulate Matter: A Comparison Study Using Two Diesel Particulate Sources.

    Burton, Kerrie A; Whitelaw, Jane L; Jones, Alison L; Davies, Brian


    Diesel engines have been a mainstay within many industries since the early 1900s. Exposure to diesel particulate matter (DPM) is a major issue in many industrial workplaces given the potential for serious health impacts to exposed workers; including the potential for lung cancer and adverse irritant and cardiovascular effects. Personal respiratory protective devices are an accepted safety measure to mitigate worker exposure against the potentially damaging health impacts of DPM. To be protective, they need to act as effective filters against carbon and other particulates. In Australia, the filtering efficiency of respiratory protective devices is determined by challenging test filter media with aerosolised sodium chloride to determine penetration at designated flow rates. The methodology outlined in AS/NZS1716 (Standards Australia International Ltd and Standards New Zealand 2012. Respiratory protective devices. Sydney/Wellington: SAI Global Limited/Standards New Zealand) does not account for the differences between characteristics of workplace contaminants like DPM and sodium chloride such as structure, composition, and particle size. This study examined filtering efficiency for three commonly used AS/NZS certified respirator filter models, challenging them with two types of diesel emissions; those from a diesel generator and a diesel engine. Penetration through the filter media of elemental carbon (EC), total carbon (TC), and total suspended particulate (TSP) was calculated. Results indicate that filtering efficiency assumed by P2 certification in Australia was achieved for two of the three respirator models for DPM generated using the small diesel generator, whilst when the larger diesel engine was used, filtering efficiency requirements were met for all three filter models. These results suggest that the testing methodology specified for certification of personal respiratory protective devices by Standards Australia may not ensure adequate protection for

  12. Respirable particulate monitoring with remote sensors. (Public health ecology: Air pollution)

    Severs, R. K.


    The feasibility of monitoring atmospheric aerosols in the respirable range from air or space platforms was studied. Secondary reflectance targets were located in the industrial area and near Galveston Bay. Multichannel remote sensor data were utilized to calculate the aerosol extinction coefficient and thus determine the aerosol size distribution. Houston Texas air sampling network high volume data were utilized to generate computer isopleth maps of suspended particulates and to establish the mass loading of the atmosphere. In addition, a five channel nephelometer and a multistage particulate air sampler were used to collect data. The extinction coefficient determined from remote sensor data proved more representative of wide areal phenomena than that calculated from on site measurements. It was also demonstrated that a significant reduction in the standard deviation of the extinction coefficient could be achieved by reducing the bandwidths used in remote sensor.

  13. Correlation Study Between Suspended Particulate Matter and DOAS Data

    SI Fuqi; LIU Jianguo; XIE Pinghua; ZHANG Yujun; LIU Wenqing; Hiroaki KUZE; Nofel LAGROSAS; Nobuo TAKEUCHI


    Continuous data of aerosol optical thickness monitored using differential optical absorption spectroscopy (DOAS) are correlated with the concentration of ground-measured suspended particulate matter (SPM).A high correlation is found between the DOAS and the ground SPM data, making it possible to calculate the mass extinction efficiency of the aerosols in the atmosphere. It is found that the value of mean mass extinction efficiency (MEE) varies over a range of 2.6-13.7 m2 g-1, with smaller and larger values occurring for size distributions dominated by coarse and fine particles, respectively.

  14. Seasonal changes in suspended particulate component in Bombay High oil field (Arabian Sea)

    Bhat, K.L.; Verlecar, X.N.; Venkat, K.

    of these constituent fractions. Almost uniform ratios of particulate lipid to particulate organic carbon (PL/POC) during all the three seasons indicated incorporation of petroleum hydrocarbons in the suspended particles....

  15. Caracterización de Partículas Suspendidas (PST y Partículas Respirables (PM 10 producidas en Áreas de Explotación Carbonífera a Cielo Abierto Characterization of Total Suspended Particles (TSP and Inhalable Particulate Matter (PM 10 generated in Open Pit Coal Mining Areas

    Luis C Angulo


    Full Text Available Se presenta una revisión de la literatura sobre la cuantificación y caracterización de partículas suspendidas (PST y partículas respirables (PM10 producidas en áreas de explotación carbonífera a cielo abierto. El material particulado es un contaminante complejo por sus características físicas (distribución de tamaño de partícula, morfología y densidad y por sus características químicas (compuestos orgánicos e inorgánicos, metales y contaminantes primarios y secundarios. Estas características son críticas para determinar el tipo y magnitud de los efectos sobre la salud humana. Se encontró que los trabajos realizados, han empleado experimentos de laboratorio y de campo, así como estudios de modelación. Esta revisión bibliográfica contribuye a una mejor comprensión y evaluación de las tecnologías que se deben usar para encontrar soluciones a este problema de contaminación.This article presents a literature review about the quantification and characterization of total suspended particles (TSP and inhalable particulate matter (PM 10 generated in open pit coal mining areas. Particle matter is a complex pollutant due to its physical characteristics (particle size distribution, morphology and density and its chemical characteristics (organic and inorganic components, metals, and primary and secondary pollutants. These characteristics are critical to determine the type and the magnitude of their effects on human health. It was found that the different works published in the literature have used lab and field experiments, and also modeling studies. This literature review contributes to improve the understanding and evaluation of technologies that must be used to find solutions to this atmospheric pollution problem.

  16. 40 CFR 227.32 - Liquid, suspended particulate, and solid phases of a material.


    ... MATERIALS Definitions § 227.32 Liquid, suspended particulate, and solid phases of a material. (a) For the... 40 Protection of Environment 24 2010-07-01 2010-07-01 false Liquid, suspended particulate, and solid phases of a material. 227.32 Section 227.32 Protection of Environment ENVIRONMENTAL...

  17. The biogeochemical reactivity of suspended particulate matter at nested sites in the Dee basin, NE Scotland.

    Dawson, J J C; Adhikari, Y R; Soulsby, C; Stutter, M I


    Variation in the organic matter content associated with suspended particulate matter (SPM) is an often overlooked component of carbon cycling within freshwater riverine systems. The potential biogeochemical reactivity of particulate organic carbon (POC) that affect its interactions and fate, i.e. respired and lost to the atmosphere along river continua or ultimately exported to estuarine and oceanic pools was assessed. Eleven contrasting sites draining nested catchments (5-1837 km(2)) in the River Dee basin, NE Scotland were sampled during summer 2008 to evaluate spatio-temporal variations in quantity and quality (biogeochemical reactivity) of SPM during relatively low flow conditions. Mean SPM concentrations increased from 0.21 to 1.22 mg L(-1) between the uppermost and lowest mainstem sites. Individually, POC concentrations ranged from 0.08 to 0.55 mg L(-1) and accounted for ca. 3-15% of total aqueous organic carbon transported. The POC content was partitioned into autotrophic (2.78-73.0 mg C g(-1) SPM) and detrital (119-388 mg C g(-1) SPM) biomass carbon content. The particulate respired CO(2)-C as a % of the total carbon associated with SPM, measured by MicroResp™ over 18 h, varied in recalcitrance from 0.49% at peat-dominated sites to 3.20% at the lowermost mainstem site. Significant (p<0.05) relationships were observed between SPM biogeochemical reactivity measures (% respired CO(2)-C; chlorophyll α; bioavailable-phosphorus) and arable and improved grassland area, associated with increasing biological productivity downstream. Compositional characteristics and in-stream processing of SPM appear to be related to contributory land use pressures, that influence SPM characteristics and biogeochemistry (C:N:P stoichiometry) of its surrounding aqueous environment. As moorland influences declined, nutrient inputs from arable and improved grasslands increasingly affected the biogeochemical content and reactivity of both dissolved and particulate matter. This

  18. 78 FR 69361 - Development of Inward Leakage Standards for Half-Mask Air-Purifying Particulate Respirators


    ... Particulate Respirators AGENCY: Centers for Disease Control and Prevention, HHS. ACTION: Reopening of comment... class of NIOSH-certified non-powered air-purifying particulate respirators approved as half-facepiece respirators for protection from particulate-only hazards. The purpose of this meeting was to share...

  19. Chlorophyll 'a' particulate organic carbon and suspended load from the mangrove areas of Cochin backwaters

    Sheeba, P.; Devi, K.S.; Balasubramanian, T.; Sankaranarayanan, V.N.

    Chlorophyll 'a' Particulate Organic Carbon and suspended load were estimated for one year from two distinct mangrove areas of Cochin backwaters, viz. Puthuvypeen and Nettoor. Environmental parameters like tau degrees C, S ppt and pH were also...

  20. Natural isotopic composition of nitrogen in suspended particulate matter in the Bay of Bengal

    Kumar, S.; Ramesh, R.; Bhosle, N.B.; Sardessai, S.; Sheshshayee, M.S.

    The first measurements of nitrogen isotopic composition (delta sup(15) N) in suspended particulate matter (SPM) of the surface Bay of Bengal (BOB) at 24 different locations during pre- (April-May 2003) and post- (September-October 2002) monsoon...

  1. Relationship between the suspended particulate matter and microorganisms in the White Sea waters

    Kravchishina, M. D.; Mitzkevich, I. N.; Veslopolova, E. F.; Shevchenko, V. P.; Lisitzin, A. P.


    During the summer periods of 2003-2005, the spatial and vertical distributions of the suspended particulate matter and bacteria in stratified and homogeneous waters of the White Sea was studied. The results of the study of various quantitative characteristics of the suspended particulate matter (first of all, the area of the surface and the volumetric and mass concentrations) and the abundance of microorganisms in the water are discussed. A direct correlation between the value of the surface area of the suspended particulate matter and the total number of bacteria in the water is revealed. However, it was manifested only during the early summer period of the observations and was not expressed at the end of the summer. The enhanced surface area of the suspended particulate matter can indicate the higher biochemical activity of its particles. The influence of the pelitic fraction on the bacteria abundance in different parts of the sea during the summer is estimated.

  2. Study of glyphosate transport through suspended particulate matter

    Amiot, Audrey; Landry, David; Jadas-Hécart, Alain; La Jeunesse, Isabelle; Sourice, Stéphane; Ballouche, Aziz


    complete (95% in 2 min). (ii) Kd obtained on the erodible fraction are two times higher than on 2 mm sieved soils. (iii) Desorption showed that glyphosate is desorbed from the erodible fraction at 40% after 25 desorptions. The aim of this study was to show the potential transport of glyphosate through suspended particulate matter. The adsorption on the erodible fraction argued to a significant transport potential of glyphosate on this fraction. The desorption of glyphosate from the erodible water fraction have revealed that the adsorption of glyphosate is reversible but it is much slower. These results demonstrate that glyphosate may be stored on the erodible fraction and be transported by these fractions. Keywords: Adsorption, Desorption, Glyphosate, Suspended Solids, Erosion.

  3. Concentrations of suspended particulate organic carbon in the tidal Yorkshire Ouse River and Humber Estuary.

    Uncles, R J; Frickers, P E; Easton, A E; Griffiths, M L; Harris, C; Howland, R J; King, R S; Morris, A W; Plummer, D H; Tappin, A D


    Data are presented for particulate organic carbon (POC) and particulate nitrogen (PN) concentrations in the Humber Estuary and tidal River Ouse Estuary. The POC data were derived from approximately monthly surveys and are consistent with data reported for suspended particulate matter (SPM) in the non-tidal River Ouse (the freshwater river) and with SPM, or bed sediments, in estuarine ecosystems such as the Mississippi, Delaware, San Francisco Bay, Tolo Harbour, the Vellar Estuary and Cochin Backwater, as well as the Loire, Gironde, Ems and Tamar Estuaries. Relative to the dry weight of SPM, the Humber-averaged organic carbon and nitrogen percentages during the year February 1995-March 1996 were 2.6 +/- 0.6% (mean and S.D.) and 0.21 +/- 0.04%, respectively. The ratio of Humber-averaged POC to Humber-averaged PN was 13 +/- 3. Higher POC levels were observed near the Humber's mouth and in the adjacent coastal zone during 'bloom' conditions, and in the upper estuarine reaches during large, winter and springtime freshwater inflows. At these times of high runoff, the POC content of SPM increased progressively up-estuary from the coastal zone to the tidal River Ouse. When inflows became very low, during late spring to early autumn of 1995, both the freshwater-saltwater interface (FSI) and the strengthening turbidity maximum (TM) moved further up-estuary and the POC content of SPM in the upper reaches of the Ouse became lower compared with that immediately down-estuary. This led to a poorly defined POC maximum near the confluence of the Humber, Ouse and Trent, before POC eventually decreased again towards the coastal zone. The lower POC contents in the upper estuarine reaches of the tidal Ouse may have been partly due to POC respiration by heterotrophic bacteria attached to SPM within the TM, consistent with the severe oxygen depletion observed there during high turbidity, summertime spring tides.

  4. Development and evaluation of personal respirable particulate sampler (PRPS)

    Lee, Seung Joo; Demokritou, Philip; Koutrakis, Petros; Delgado-Saborit, Juana M.

    This paper presents the development, laboratory evaluation, and field tests of a personal respirable particulate sampler (PRPS). The PRPS is designed as a personal sampling system to collect particulate matter (PM 0.5, PM 1.0, PM 2.5, PM 4.5, and PM 10) and gaseous pollutants, including O 3, SO 2, and NO 2. It operates at a flow rate of 5.0 LPM and consists of five selectable impaction stages (with cutpoints of 10, 4.5, 2.5, 1.0, and 0.5 μm), a backup filter, and two diffusion passive samplers. In each impaction stage, particles are collected onto a polyurethane foam (PUF) substrate. This substrate, using no adhesive, was shown to have minimum particle bounce and re-entrainment. A backup 37 mm Teflon membrane filter is used downstream to collect particles smaller than the cutoff diameter of the final impaction stage. The impaction stage cutpoints were characterized in the laboratory using artificially generated polydisperse aerosols. Particle losses for each stage were found to be acceptably low. The performance of the PRPS was also compared with that of a collocated micro-orifice cascade impactor (MOI) and real-time particle sizing instruments (SMPS/APS) in laboratory experiments using artificially generated particles. The size distributions measured by the PRPS were found to be much closer to those measured by the real-time particle sizing instruments than to those measured by the MOI. A field PM intercomparison study was also conducted using the PRPS and three reference samplers, the Harvard Impactor (HI), the USEPA PM 2.5 Well Impactor Ninety Six (WINS), and the Harvard Personal Environmental Monitor (Harvard PEM) sampler. The PM 10, PM 2.5, and sulfate concentrations measured by PRPS were in a very good agreement with those obtained from the reference samplers.

  5. Distribution and composition of suspended particulate matter in the Atlantic Ocean: Direct measurements and satellite data

    Lisitzin, A. P.; Klyuvitkin, A. A.; Burenkov, V. I.; Kravchishina, M. D.; Politova, N. V.; Novigatsky, A. N.; Shevchenko, V. P.; Klyuvitkina, T. S.


    The main purpose of this work is to study the real distribution and spatial-temporal variations of suspended particulate matter and its main components in surface waters of the Atlantic Ocean on the basis of direct and satellite measurements for development of new and perfection of available algorithms for converting satellite data. The distribution fields of suspended particulate matter were calculated and plotted for the entire Atlantic Ocean. It is established that its distribution in the open ocean is subordinate to the latitudinal climatic zonality. The areas with maximum concentrations form latitudinal belts corresponding to high-productivity eutrophic and mesotrophic waters of the northern and southern temperate humid belts and with the equatorial humid zone. Phytoplankton, the productivity of which depends primarily on the climatic zonality, is the main producer of suspended particulate matter in the surface water layer.

  6. Behavior of different phosphorus species in suspended particulate matter in the Changjiang estuary

    HE Huijun; Chen Hongtao; Yao Qingzhen; Qin Yanwen; MI Tiezhu; YU Zhigang


    Suspended particulate matter (SPM) collected in the Changjiang (Yangtze River) estuary in June 2006 was separated into five fractions via water elutriation: clay-very fine silt (63 μm). The SPM and fractionated particles were sequentially analyzed by a modified SEDEX sequential extraction method to obtain six species of phosphorus: exchangeable or loosely-sorbed P, organic P, Fe-bound P, authigenic P, detrital P and refractory P. The results indicated that all particulate phosphorus species except for detrital P were negatively correlated to particle size; a high detrital P content was found in coarse silt and very coarse silt. From the inside of the river mouth to the gate of the river mouth, organic P, Fe-bound P and refractory P in the suspended particles decreased and a higher amount of exchangeable P appeared around the gate of the river mouth. From the gate of the river mouth to the sea, exchangeable P and organic P in suspended particles increased distinctly. The total particulate P flux into the estuary from the Changjiang River was about 45.45×10~8 μmol/s during sampling. Of this, about 8.27×10~8 μmol/s was associated with the "truly suspended" fraction. The bio-available particulate P flux was about 13.58×10~8 μmol/s. Of this, about 4.24×10~8 μmol/s was transported by "truly suspended" particles.

  7. Characterization of respirable mine dust and diesel particulate matter

    Mahlangu, Vusi J


    Full Text Available This paper presents the preliminary outcomes to develop and optimize methods to characterize DPM and respirable dust samples for the following: Crystalline compounds Common mineral analyses Particle size distribution Elemental Carbon (EC...

  8. Personal exposure to total suspended particulates of adolescents living in Vanderbijlpark, South Africa

    Terblanche, APS


    Full Text Available Personal monitoring of exposure to air pollution is becoming increasingly important in health studies as a method of characterizing total exposure. We monitored the exposure of 31 teenagers to total suspended particulates (TSP) over a 12-hour period...

  9. Trace metals in suspended particulate matter and sediments from the Severnaya Dvina estuary, Russian Arctic

    Koukina, S.E.; Calafat-Frau, A.; Hummel, H.; Palerud, R.


    A geochemical study of the Severnaya Dvina estuary was carried out during two oceanographic cruises to the White Sea. The amount and distribution of trace (Mn, Co, Cu, Ni, Pb, and Zn) and major (Al and Fe) elements in suspended particulate matter and sediments were determined. The main source of

  10. Retrieval of suspended particulate matter concentrations in the Danube River from Landsat ETM data.

    Onderka, Milan; Pekárová, Pavla


    Alternations in river channel morphology result in a disturbed natural transport of suspended particulate matter (SPM). Suspended particulate matter serves as a transport medium for various pollutants, e.g. heavy metals. It is therefore important to understand how artificial obstructions alter the natural transport of suspended matter. Measurements of SPM in rivers are traditionally carried out during in situ sampling campaigns, which can provide only a limited view of the actual spatial distribution of suspended matter over large distances. Several authors have studied how space-borne remote sensing could be used for mapping of water quality in standing waters, but with only little attention paid to rivers. This paper describes the methodology how a Landsat ETM image was used to map the spatial patterns of SPM in the Slovak portion of the Danube River. Results of our investigation reveal that the Danube River in Slovakia exhibits gradual longitudinal decrease in concentrations of SPM. Based on a strong relationship between the Landsat near-infrared band (TM4) and field measurements, we developed a map of suspended particulate matter in the Danube River with a standard error (SE) of 2.92 mg/L. This study aims to show how archived satellite data and historical water quality data can be used for monitoring of SPM in large rivers. A methodology describing the minimum samples required for sufficiently accurate results is discussed in this paper also.

  11. Suspended particulate organic matter in a Mediterranean submarine cave

    Fichez, Renaud


    Les concentrations en carbone et azote organique, glucide, protéine et lipide des particules en suspension ont été déterminées entre juillet 1985 et juillet 1987 dans une grotte sous-marine de Méditerranée. La matière organique particulaire diminue nettement entre l'entrée et la zone terminale obscure. Cet appauvrissement fait appel à trois processus; (i) diminution du seston; (ii) diminution du pourcentage de matière organique; (iii) proportion croissante des géopolymères dans la fraction or...

  12. Metals in Nile perch (Lates niloticus) and suspended particulate matter from Lake Victoria, Tanzania.

    Machiwa, John F


    A study was conducted to assess the levels of pollutant metals in suspended particulate matter and Nile perch from Lake Victoria. The metals in particulate matter were determined to ascertain their concentrations at the base of the food chain. Nile perch samples were collected in September 2003 from five major fish processing factories at the shores of Lake Victoria in Mwanza and Musoma. The concentrations of total Hg, Pb, Cd, and Cu were generally low in particulate matter and in most locations were close to or below their limits of detection. The concentrations of Zn were high in suspended particulate matter, the highest being 219.4 +/- 153.0 microg L(-1) found in particulate matter from Nungwe Bay in the southern part of Lake Victoria. Nile perch generally contained low levels of heavy metals; the range for Pb was Food and Agriculture Organization of the United Nations/World Health Organization (1000 ng total Hg g(-1) ww for piscivorous fish species) maximum allowable level. Indeed, all Nile perch samples that weighed less than 10 kg had less than 200 ng total Hg g(-1) ww and therefore are safe for regular consumption by at-risk groups such as children and pregnant women. Levels of mercury and other heavy metals in Nile perch at present is, therefore, not a severe environmental issue; however, urgent regulatory measures should be taken to minimize metal input into the lake to maintain the current levels in the fish.

  13. Genotoxicity and Mutagenicity of Suspended Particulate Matter of River Water and Waste Water Samples

    Georg Reifferscheid


    Full Text Available Suspended particulate matter of samples of river water and waste water treatment plants was tested for genotoxicity and mutagenicity using the standardized umu assay and two versions of the Ames microsuspension assay. The study tries to determine the entire DNA-damaging potential of the water samples and the distribution of DNA-damaging substances among the liquid phase and solid phase. Responsiveness and sensitivity of the bioassays are compared.

  14. Estimation on dynamic release of phosphorus from wind-induced suspended particulate matter in Lake Taihu

    FAN; Chengxin; ZHANG; Lu; QIN; Boqiang; WANG; Sumin; HU; We


    Through man-made disturbance experiments, the corresponding relationships between suspended particulate matter (SPM) and wind speed in different lake areas were simulated, the physicochemical formal transformation and biological mineralizing and decaying processes of phosphorus in SPM were studied, the contribution of phosphorus transformation to phosphorus loading of the water of Lake Taihu was quantitatively estimated. The results show SPM in physicochemical transformed to soluble reactive phosphorus (SRP), and the contribution of the total external loading of Lake Taihu, namely 4.7-7.5 times as much as SRP loading entering the lake by the rivers; thus it is the important source in dynamical internal loading of the lake. The determining factors for dynamical internal loading in lakes are organic phosphorus content in suspended solid and its biological transition availability.

  15. Analysis of concentration levels of particulate matter (PM10, total suspended particulates and black smoke in the city of Zrenjanin

    Vujić Bogdana B.


    Full Text Available Air quality monitoring on the territory of AP Vojvodina was initiated in mid 90s. During the last decade of the 20th century the development of the air quality monitoring in Serbia didn’t keep up with the pace of the other countries in the region due to political isolation and severe economic crisis. Monitoring of the particular pollutants was conducted unsystematically and sporadically. Data presented in this paper were obtained on the territory of the city of Zrenjanin, which represents typical agglomeration in the region in regard to its geographical location, population, level of industry development and the presence of natural gas as energy product in the remote and domestic heating system of residential objects. Available data on the concentration levels of PM10 (particulate matter with aerodynamic diameter less than 10 μm, TSP (total suspended particulates and BS (black smoke during the period of 2005-2007 (three cold and three warm seasons have been used in this work in order to carry out analysis and comparison of the daily concentration levels of PM10, TSP and BS and their seasonal variation.

  16. Suspended particulate matter in Jiaozhou Bay:Properties and variations in response to hydrodynamics and pollution

    YANG Shilun; YANG Hua; WANG Liang; ZHANG Wenxiang; MENG Yi; ZHANG Jing; XUE Yuanzhong; CHEN Hongtao; WEI Hao; LIU Zhe; WU Ruiming; WANG Lingxiang


    Based on water samples collected and observations of currents, tidal levels as well as turbidities taken, respectively over a period of 15 and 7 d, in southwestern Jiaozhou Bay on August, 2001, it was found that: (ⅰ) the average content of non mineral component amounted to 87% of the suspended sediment matter (SPM) in Jiaozhou Bay, much higher than in estuaries and bays where turbidity is high and mineral particulates dominates; (ⅱ) in contrast to high turbid bays, SPM was generally coarser than bed deposits and in upper water column than in lower water column in Jiaozhou Bay; (ⅲ) in fair weathers, suspended sediment concentration (SPC) varied regularly within tidal cycles and neap-spring cycles, but the regularity was deformed in storms; and (ⅳ) SPC was controlled by settling/ resuspension near the bed and by advection at the surface at the study site with a depth of 20 m, suggesting weak vertical exchanges. It was concluded that SPM property of a low turbid bay is sensitive to pollution, and that the maintenance of low turbidity in the bay depends on less SPM supply, low waves and currents, and controlling on discharge of particulate pollutants.

  17. A review of the effects of particle types on oil-suspended particulate matter aggregate formation

    Loh, Andrew; Yim, Un Hyuk


    Oil-suspended particulate matter aggregate (OSA) can form naturally when oil and particles interact. The interaction between oil and suspended particulate matter makes oil less sticky, and facilitates its dispersion in the water column. The high oil-water surface contact enhances the biodegradation of oil and thus increases the efficiency of remediation processes. There are many factors that affect OSA formation, but, particle type is one of the most important. Because different particle types have different physical, chemical, and biological properties, their interactions with oil differ greatly. Particle properties such as interlayer spaces, hydrophobicity, surface charges, polarity, organic content, and size affect the interactions between materials and oil. These different interactions determine the type, buoyancy, size, and stability of OSA that forms, thus determining its fate in the environment. This review provides a current understanding of (1) OSA formation mechanisms, (2) sources and classes of marine materials, (3) oil-particle interactions, (4) material properties and their effects on oil interaction, and (5) future research needs.

  18. Powered, air-purifying particulate respirator filter penetration by a DOP aerosol.

    Martin, Stephen; Moyer, Ernest; Jensen, Paul


    In 1995, new certification requirements for all nonpowered, air-purifying particulate filter respirators were put in place when 42 CFR 84 replaced 30 CFR 11. However, the certification requirements for all other classes of respirators, including powered air-purifying respirators (PAPRs), were transferred to 42 CFR 84 from 30 CFR 11 without major changes. Since the inception of 42 CFR 84, researchers have learned that the efficiency of electrostatic filter media, in contrast with mechanical filter media, can be rapidly degraded by oil aerosols. Further, confusion may exist among respirator users, since electrostatic PAPR filters have the same magenta color assigned to high-efficiency filters for nonpowered particulate respirators that have been tested and certified for use against oil aerosols (i.e., P100 filters). Users may expect that the magenta color of certified PAPR filters indicates suitability for use against oil aerosols. This may not be the case. To illustrate the potential degradation of electrostatic PAPR filters, new filters certified under 42 CFR 84 were tested using a TSI model 8122 Automated Respirator Tester against charged and neutralized DOP aerosols with intermittent loading schedules. The performance of a magenta-colored electrostatic PAPR filter--one for which the manufacturer's user instructions appropriately indicates is not suitable for use in oily environments--was compared with the performance of several mechanical PAPR filters. In tests against both DOP aerosols, the electrostatic PAPR filter showed a significant decrease in performance at DOP loadings exceeding 400 mg, whereas mechanical filters showed no significant change in the performance except at extremely high loadings. The decreased performance of the electrostatic PAPR filter was found to be significantly greater when tested against a neutralized DOP aerosol when compared with a charged DOP aerosol. While laboratory tests show that the filtration efficiency of this electrostatic

  19. Analisis Epidemiologis Efek Paparan Debu ( Total Suspended Particulates) Terhadap Kondisi Kesehatan Karyawan Petugas Pintu Tol Belmera Medan

    Silitonga, Evawani Martalena


    Air was mixed by various kinds of gases. Air quality in Indonesia now is showing degradation. The increase of economic development has made the industrialization and transportasion became higher and they has been contributed to the increased of air polution, include the Total Suspended Partculates (TSP). Vehicle trasnportations are the major contributor for the increasing of air polution on the street. Highway gate employees are the most susceptible affected by The Total Suspended Particul...

  20. Chlorophyll a in suspended particulate matter of the Caspian Sea as an indicator of biogenic sedimentation conditions

    Kravchishina, M. D.; Klyuvitkin, A. A.; Pautova, L. A.; Politova, N. V.; Lein, A. Yu.; Lisitzin, A. P.


    The conditions of biogenic sedimentation (concentration of chlorophyll a (chl a), particulate organic carbon (POC), and its isotope composition (δ13CPOC)), as well as the quantitative characteristics of phytoplankton, and the total concentration of suspended particulate matter have been studied in the Caspian Sea in May and June 2012. The vertical (from the surface layer to bottom) distribution and precipitation of the biogenic component of suspended particulate matter have been determined. It was found that only 5% of the particulate matter and around 3% of POC reached the Middle Caspian after passing through a marginal filter (Volga River delta-Northern Caspian). The subsurface chl a maximum layer (around 20-60 m) with a cold-water phytoplankton community was revealed in the Middle and Southern Caspian. The subsurface region of accumulation of chl a and phytoplankton in the subthermocline layer has been extended from the southern periphery of the Derbent Depression to the Absheron Sill.

  1. Land-use impacts on fatty acid profiles of suspended particulate organic matter along a larger tropical river

    Boëchat, Iola; Krüger, Angela; Chavez, R.C.


    . Here, we analyzed land-use effects on the fatty acid (FA) composition and concentrations in suspended particulate organic matter (SPOM) along a fourth-order tropical river, the Rio das Mortes. Thereby, we aimed at testing the potential of fatty acids in riverine suspended particulate organic matter...... (SPOM-FAs) as indicators of land-use change in tropical catchments, and at identifying major human impacts on the biochemical composition of SPOM, which represents an important basal energy and organic matter resource for aquatic consumers. River water SPOM and total FA concentrations ranged between 2...

  2. Workplace field testing of the pressure drop of particulate respirators using welding fumes.

    Cho, Hyun-Woo; Yoon, Chung-Sik


    In a previous study, we concluded that respirator testing with a sodium chloride aerosol gave a conservative estimate of filter penetration for welding fume aerosols. A rapid increase in the pressure drop (PD) of some respirators was observed as fumes accumulated on the filters. The present study evaluated particulate respirator PD based on workplace field tests. A field PD tester was designed and validated using the TSI 8130 Automatic Filter Tester, designed in compliance with National Institute for Occupational and Safety and Health regulation 42 CFR part 84. Three models (two replaceable dual-type filters and one replaceable single-type filter) were evaluated against CO(2) gas arc welding on mild steel in confined booths in the workplace. Field tests were performed under four airborne concentrations (27.5, 15.4, 7.9, and 2.1 mg m(-3)). The mass concentration was measured by the gravimetric method, and number concentration was monitored using P-Trak (Model 8525, TSI, USA). Additionally, photos and scanning electron microscopy-energy dispersive X-ray spectroscopy were used to visualize and analyze the composition of welding fumes trapped in the filters. The field PD tester showed no significant difference compared with the TSI tester. There was no significant difference in the initial PD between laboratory and field results. The PD increased as a function of fume load on the respirator filters for all tested models. The increasing PD trend differed by models, and PD increased rapidly at high concentrations because greater amount of fumes accumulated on the filters in a given time. The increase in PD as a function of fume load on the filters showed a similar pattern as fume load varied for a particular model, but different patterns were observed for different models. Images and elemental analyses of fumes trapped on the respirator filters showed that most welding fumes were trapped within the first layer, outer web cover, and second layer, in order, while no fumes

  3. Simulation of the transport of suspended particulate matter in the Rio de la Plata

    Hausstein, H.


    Numerical simulations of the transport of Suspended Particulate Matter in the Rio de la Plata estuary were performed with a three dimensional model for coastal waters driven by wave sand currents. Aturbulence based flocculation approach is implemented to the model. The model is for the first time applied under heavy conditions, since the Rio de la Plata has discharges up to 25000 m{sup 3}/s and SPM concentrations up to 300-400 mg/l. Such concentrations are also difficult to compute from satellite measurements. SeaWiFs satellite images served for the validation of the model results. The model is able to reproduce the shape and the position of the front as well as the zone of the turbidity maximum. It also identifies the zones of erosion and deposition which is of significant importance because of the dense ship traffic along the navigational channels towards Buenos Aires and the cities upstream the rivers. (orig.)

  4. Oil-suspended particulate matter aggregates: Formation mechanism and fate in the marine environment

    Loh, Andrew; Shim, Won Joon; Ha, Sung Yong; Yim, Un Hyuk


    Oil suspended particulate matter (SPM) aggregates (OSA) are naturally occurring phenomena where oil droplets and particles interact to form aggregates. This aggregation could aid cleanup processes of oil contaminated waters. When OSA is formed, it makes oil less sticky and would facilitate the dispersion of oil into the water column. Increased oil-water surface contact by OSA formation enhances biodegradation of oil. Its applicability as a natural oil clean-up mechanism has been effectively demonstrated over past decades. There are many factors affecting the formation of OSA and its stability in the natural environment that need to be understood. This review provides a current understanding of (1) types of OSA that could be formed in the natural environment; (2) controlling factors and environmental parameters for the formation of OSA; (3) environmental parameters; and (4) fate of OSA and its applicability for oil spill remediation processes.

  5. Estuarine suspended particulate matter concentrations from sun-synchronous satellite remote sensing: tidal and meteorological effects and biases

    Eleveld, M.A.; van der Wal, D.; van Kessel, T.


    Optical data from a sun-synchronous satellite were used to investigate how large-scale estuarine suspended particulate matter (SPM) concentrations were affected by tidal and bulk meteorological drivers, and how retrieved SPM is biased by tidal aliasing and sampling under clear sky conditions. Local

  6. Fate of the Evros River suspended particulate matter in the northern Aegean Sea

    Kanellopoulos, Theodore D.; Angelidis, Michael O.; Georgopoulos, Dimitrios; Karageorgis, Aristomenis P.


    Evros River is the most important river flowing into the North Aegean Sea (eastern Mediterranean) in terms of freshwater discharge, and the second largest one of Eastern Europe after the Danube River. Salinity and temperature measurements, together with suspended particulate matter concentrations were obtained in various depths at 14 stations in the adjacent Alexandroupolis Gulf during four seasons (June 1998, September 1998, February 1999 and March 2000) in order to investigate the particle dynamics and distributions in the northern Aegean Sea. Analysis of the collected data, together with particle observations under the scanning electron microscope and study of satellite images showed that, under certain circumstances driven by the hydrological and wind regime of the area, the Evros River particulate matter, with the associated pollutants, can be transferred far away from the estuary and implicitly comprise a hazardous factor for the environmental status of the northern Aegean Sea. This fact, combined with the future construction of the Burgas-Alexandroupolis pipeline, may cause a negative impact on the studied natural ecosystem.

  7. Comparison of pressure drop and filtration efficiency of particulate respirators using welding fumes and sodium chloride.

    Cho, Hyun-Woo; Yoon, Chung-Sik; Lee, Jin-Ho; Lee, Seung-Joo; Viner, Andrew; Johnson, Erik W


    Respirators are used to help reduce exposure to a variety of contaminants in workplaces. Test aerosols used for certification of particulate respirators (PRs) include sodium chloride (NaCl), dioctyl phthalate, and paraffin oil. These aerosols are generally assumed to be worst case surrogates for aerosols found in the workplace. No data have been published to date on the performance of PRs with welding fumes, a hazardous aerosol that exists in real workplace settings. The aim of this study was to compare the performance of respirators and filters against a NaCl aerosol and a welding fume aerosol and determine whether or not a correlation between the two could be made. Fifteen commercial PRs and filters (seven filtering facepiece, two replaceable single-type filters, and six replaceable dual-type filters) were chosen for investigation. Four of the filtering facepiece respirators, one of the single-type filters, and all of the dual-type filters contained carbon to help reduce exposure to ozone and other vapors generated during the welding process. For the NaCl test, a modified National Institute for Occupational Safety and Health protocol was adopted for use with the TSI Model 8130 automated filter tester. For the welding fume test, welding fumes from mild steel flux-cored arcs were generated and measured with a SIBATA filter tester (AP-634A, Japan) and a manometer in the upstream and downstream sections of the test chamber. Size distributions of the two aerosols were measured using a scanning mobility particle sizer. Penetration and pressure drop were measured over a period of aerosol loading onto the respirator or filter. Photos and scanning electron microscope images of clean and exposed respirators were taken. The count median diameter (CMD) and mass median diameter (MMD) for the NaCl aerosol were smaller than the welding fumes (CMD: 74 versus 216 nm; MMD: 198 versus 528 nm, respectively). Initial penetration and peak penetration were higher with the NaCl aerosol

  8. Circulation and suspended particulate matter transport in a tidally dominated estuary: caravelas estuary, Bahia, Brazil

    Carlos Augusto França Schettini


    Full Text Available The circulation and transport of suspended particulate matter in the Caravelas Estuary are assessed. Nearly-synoptic hourly hydrographic, current (ADCP velocity and volume transport and suspended particulate matter data were collected during a full semidiurnal spring tide, on the two transects Boca do Tomba and Barra Velha and on longitudinal sections at low and high tide. On the first transect the peak ebb currents (-1.5 ms-1 were almost twice as strong as those of the wider and shallow Barra Velha inlet (-0.80 ms-1 and the peak flood currents were 0.75 and 0.60 ms-1, respectively. Due to the strong tidal currents both inlets had weak vertical salinity stratification and were classified with the Stratification-circulation Diagram as Type 2a (partially mixed-weakly stratified and Type 1a (well mixed. Volume transports were very close, ranging from -3,500 to 3,100 m³s-1 at the ebb and flood, respectively, with a residual -630 m³s-1. The concentration of the suspended particulate matter was closely related to the tidal variation and decreased landwards from 50 mg.L-1 at the estuary mouth, to 10 mg.L-1 at distances of 9 and 16 km for the low and high tide experiments, respectively. The total residual SPM transport was out of the estuary at rates of -18 tons per tidal cycle.A circulação e o transporte de material particulado em suspensão no Estuário de Caravelas são pesquisados. Dados quase-sinóticos hidrográficos, de correntes (velocidade e transporte de volume com ADCP e de material particulado em suspensão, foram medidos em intervalos horários durante um ciclo semidiurno de maré de sizígia, em duas seções transversais na Boca do Tomba e na Barra Velha e também em seções longitudinais na baixa-mar e na preamar. Na primeira transversal as correntes máximas de vazante (-1,50 m s-1 foram quase duas vezes mais intensas do que na seção transversal mais larga e rasa Barra Velha, (-0,80 m s-1 e as maiores velocidades das correntes de

  9. Production of potentially hazardous respirable silica airborne particulate from the burning of sugarcane

    Le Blond, Jennifer S.; Williamson, Ben J.; Horwell, Claire J.; Monro, Alex K.; Kirk, Caroline A.; Oppenheimer, Clive

    In some areas of the world where agricultural burning is practised, the airborne particles produced have been linked to respiratory disease in humans. Here, we investigate the abundance and form of silica (SiO 2) minerals found within ash and aerosol produced by the experimental burning of sugarcane. Samples of sugarcane leaf were incinerated over a range of temperatures, time scales and airflow conditions, the latter to investigate the effects of wind and updrafts during natural fires. The silica content of the residual ash (from still air simulations) was measured using an improved wet chemical methodology, described here. This indicated that the release of silica from the plant material into the atmosphere increases with increasing temperature of combustion. Airborne particulate, sampled using air-pump-filter apparatus, was characterised using scanning electron microscopy (SEM) with automated image and elemental analysis. For airborne particulate formed at 1100 °C (with airflow), 17% of the particles are in the respirable size fraction (release of cristobalite to the atmosphere (as sampled on filters). This pilot study shows that potentially toxic particles could be released during sugarcane burning and reinforces the need for further study into the emissions and re-suspension of ash from the burning of biomass.

  10. Vertical distribution of suspended particulate matter in the Caspian Sea in early summer

    Kravchishina, M. D.; Lein, A. Yu.; Pautova, L. A.; Klyuvitkin, A. A.; Politova, N. V.; Novigatsky, A. N.; Silkin, V. A.


    The features of the vertical distribution of chlorophyll a, particulate organic carbon and its isotopic composition, total suspended particulate matter (SPM), and the structure of the phytoplankton community in the Middle and South Caspian Sea in May-June 2012 are discussed. The subsurface chlorophyll a maximum (SCM) was found everywhere at depths of 20 to 40-60 m. The position of this layer is confined to the depth of the seasonal thermocline, which is determined by the development of a cold-water (dark) phytocenosis. The genesis of this layer was studied. The increase in chlorophyll a concentration in this layer is caused by an abundance of phytoplankton or an increased concentration of this phytopigments per algal cell. The highest values of the studied organic compounds and phytoplankton biomass are revealed as close to the seasonal thermocline extending from the southern periphery of the Derbent Depression to the Apsheron Sill, which is determined by the bottom topography. The presence of chlorophyll a at depths exceeding 300 m (up to ≥1 mg/m3) was revealed. This was supported by findings of individual algal cells containing chlorophyll a and even their accumulations in the deep water layer. The most probable mechanisms responsible for the presence of these cells at the deep water level are discussed in the paper. The vertical distribution of the values of the organic carbon isotopic composition is primarily controlled by the vertical structure of phytoplankton and chlorophyll a in the water column up to 500 m and by biogeochemical processes at the redox barrier ( 600 m layer). The relative stability of chlorophyll a and the stability of pheophytin a in anaerobic environments were verified. A significant amount of weakly transformed chlorophyll a was found close the sea bottom.

  11. Macromodel for assessing residential concentrations of combustion-generated pollutants: Model development and preliminary predictions for CO, NO/sub 2/, and respirable suspended particles

    Traynor, G.W.; Aceti, J.C.; Apte, M.G.; Smith, B.V.; Green, L.L.; Smith-Reiser, A.; Novak, K.M.; Moses, D.O.


    A simulation model (also called a ''macromodel'') has been developed to predict residential air pollutant concentration distributions for specified populations. The model inputs include the market penetration of pollution sources, pollution source characteristics (e.g., emission rates, source usage rates), building characteristics (e.g., house volume, air exchange rates), and meteorological parameters (e.g., outside temperature). Four geographically distinct regions of the US have been modeled using Monte Carlo and deterministic simulation techniques. Single-source simulations were also conducted. The highest predicted CO and NO/sub 2/ residential concentrations were associated with the winter-time use of unvented gas and kerosene space heaters. The highest predicted respirable suspended particulate concentrations were associated with indoor cigarette smoking and the winter-time use of non-airtight wood stoves, radiant kerosene heaters, convective unvented gas space heaters, and oil forced-air furnaces. Future field studies in this area should (1) fill information gaps identified in this report, and (2) collect information on the macromodel input parameters to properly interpret the results. It is almost more important to measure the parameters that affect indoor concentration than it is to measure the concentrations themselves.

  12. Oil-suspended particulate material aggregates as a tool in preventing potential ecotoxicological impacts in the São Paulo river, Todos os Santos Bay, Bahia, Brazil: Influence of salinity and suspended particulate material.

    Miranda, Lorena S; Moreira, Ícaro T A; Oliveira, Olívia M C; Santos, Carlito P; Pinheiro, Samires M M; Oliveira, Lua M L; Martins, Adriele B O; Filho, Milton S C


    Recent studies have revealed the occurrence of a natural process of interaction between oil droplets and suspended particulate material, resulting in the formation of aggregates which are dispersed in the water column, known as oil-suspended particulate material aggregates (OSAs). The experiments aimed to investigate the contribution of OSAS in indicating where most likely is the oil sedimentation in the São Paulo river, Todos os Santos Bay, Brazil, in order to predict possible ecotoxicological risks caused by oil spills. The results showed that salinity and MPS concentration interfere on the formation of aggregates. In addition, the point 3 was nominated as the most vulnerable area to the potential ecotoxicological impacts of oil spills and should be treated as a priority area for the application of preventive and mitigating techniques. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Pyrophaeophorbide- a as a tracer of suspended particulate organic matter from the NE Pacific continental margin

    Bianchi, Thomas S.; Bauer, James E.; Druffel, Ellen R. M.; Lambert, Corey D.

    Pyrophaeophorbide- a, a degradation product of chlorophyll- a, is predominantly formed by grazing processes in sediments as well as in the water column. Water column profiles of pyrophaeophorbide- a/suspended particulate organic carbon (SPOC) concentrations, at an abyssal site in the northeast (NE) Pacific (Sta M, 34°50'N, 123°00'W; 4100 m water depth), show low concentrations (0.01-0.1 ng/μg SPOC) at surface and mesopelagic depths, and increasing concentrations with closer proximity to the sea floor (0.05-0.6 ng/μg SPOC). However, in June 1992, the deep maximum of pyrophaeophorbide- a/SPOC in the water column of Sta M extended higher into the water column, as much as 1600 m above the bottom (mab) (2500 m water depth); in other seasons they only extended up to 650 mab (3450 m water depth). Previous studies have demonstrated lateral transport of particulate matter from the continental shelf to the deep ocean off the coast of northern California. Recent work suggests that the benthic boundary layer (BBL) extends to 50 mab, based on sediment trap and transmissometry measurements (Smith, K.L., Kaukmann, R.S., Baldwin, R.J., 1994. Coupling of near-bottom pelagic and benthic processes at abyssal depths. Limnology and Oceanography 39, 1101-1118.), and that lateral transport is significant only during summer, which is consistent with our observations. A partial vertical profile of pyrophaeophorbide- a/SPOC from the north central (NC) Pacific provides some evidence that the deep maximum may be absent due to the distance of this site from the continental margin. Thus, the observed deep maximum of pyrophaeophorbide- a/SPOC at Sta M is likely due mainly to lateral transport from the continental slope rather than to local vertical resuspension in the BBL exclusively. Pyrophaeophorbide- a concentrations in SPOC at Sta M were negatively correlated with Δ 14C values of SPOC (SPOC samples from Druffel, E.R.M., Bauer, J.E., Williams, P.M., Griffin, S.A. and Wolgast, D., 1996

  14. Chemical characterisation of total suspended particulate matter from a remote area in Amazonia

    Gonçalves, Cátia; Figueiredo, Bernardino R.; Alves, Célia A.; Cardoso, Arnaldo A.; da Silva, Rodrigo; Kanzawa, Simone H.; Vicente, Ana Margarida


    This research had as study object the total suspended particulate matter collected in the Alenquer region, a remote area in the Pará state. The main objectives were the characterisation of the inorganic and organic chemical composition of the aerosol, looking for seasonal patterns and the identification of probable emission sources and formation processes. A set of 30 samples were collected in the rainy (April-May) and dry season (August-September) of 2014. The analytical methods included gravimetric analysis, water-soluble ions analysis by ion chromatography (IC), elemental analysis by inductively coupled plasma mass spectrometry (ICP-MS) equipped with collision cell technology, carbonaceous content determination with a thermal-optical system and organic speciation by gas chromatography-mass spectrometry (GC-MS). The average concentrations of particulate matter ranged from 14 ± 1.3 μg·m- 3 to 31 ± 7.8 μg·m- 3, in the rainy and dry season, respectively. The carbonaceous content represented, on average, approximately 27% and 21% of the particulate matter in the rainy and dry season, respectively. Na+, Cl-, SO₄2 -, and NO₃- yield the highest concentrations in both seasons. Na was the dominant element, reflecting the transport of air masses from the Atlantic. An increase in concentrations between the rainy and dry seasons was especially noted for the terrigenous elements such Mn, Fe and Al. The chromatographically resolved organics included n-alkanes, n-alkenes, PAHs, n-alkanoic acids, n-di-acids, resin acids and some phenolic compounds. The primary inputs of organic constituents to the aerosols of Alenquer based on the homologous compound series and biomarkers were: (i) natural emissions from terrestrial higher plants waxes, particularly in dry season; (ii) anthropogenic emissions from diesel fuel combustion and biomass combustion, predominating during the dry season. The chemical characterisation along with the backward trajectory cluster analysis

  15. Crystalline silica dust and respirable particulate matter during indoor concrete grinding - wet grinding and ventilated grinding compared with uncontrolled conventional grinding.

    Akbar-Khanzadeh, Farhang; Milz, Sheryl; Ames, April; Susi, Pamela P; Bisesi, Michael; Khuder, Sadik A; Akbar-Khanzadeh, Mahboubeh


    The effectiveness of wet grinding (wet dust reduction method) and ventilated grinding (local exhaust ventilation method, LEV) in reducing the levels of respirable crystalline silica dust (quartz) and respirable suspended particulate matter (RSP) were compared with that of uncontrolled (no dust reduction method) conventional grinding. A field laboratory was set up to simulate concrete surface grinding using hand-held angle grinders in an enclosed workplace. A total of 34 personal samples (16 pairs side-by-side and 2 singles) and 5 background air samples were collected during 18 concrete grinding sessions ranging from 15-93 min. General ventilation had no statistically significant effect on operator's exposure to dust. Overall, the arithmetic mean concentrations of respirable crystalline silica dust and RSP in personal air samples during: (i) five sessions of uncontrolled conventional grinding were respectively 61.7 and 611 mg/m(3) (ii) seven sessions of wet grinding were 0.896 and 11.9 mg/m(3) and (iii) six sessions of LEV grinding were 0.155 and 1.99 mg/m(3). Uncontrolled conventional grinding generated relatively high levels of respirable silica dust and proportionally high levels of RSP. Wet grinding was effective in reducing the geometric mean concentrations of respirable silica dust 98.2% and RSP 97.6%. LEV grinding was even more effective and reduced the geometric mean concentrations of respirable silica dust 99.7% and RSP 99.6%. Nevertheless, the average level of respirable silica dust (i) during wet grinding was 0.959 mg/m(3) (38 times the American Conference of Governmental Industrial Hygienists [ACGIH] threshold limit value [TLV] of 0.025 mg/m(3)) and (ii) during LEV grinding was 0.155 mg/m(3) (6 times the ACGIH TLV). Further studies are needed to examine the effectiveness of a greater variety of models, types, and sizes of grinders on different types of cement in different positions and also to test the simulated field lab experimentation in the field.

  16. An in situ filtration system for trace element determination in suspended particulate matter

    Grotti, Marco; Soggia, Francesco; Dalla Riva, Simona; Magi, Emanuele; Frache, Roberto


    A system for in situ filtration of suspended particulate matter (SPM) has been developed specifically for trace element determination. Minimization of metal contamination sources was realized by careful choice of materials and designing a ''closed-open-closed'' electronic procedure for the soaking of the system. In order to prevent undesired pressure increase due to the filter clogging and to avoid modification of metal distribution in the different phases of SPM, a relief valve was used to keep the pumping pressure constant. The possibility to perform a sub-sampling of SPM was also taken into account to expand the analytical capabilities. Finally, the sampler was equipped with a multiparametric probe in order to carry out real-time measurements of physical parameters (temperature, salinity, fluorescence, turbidimetry) and operating conditions (flow rates, filtered volumes, energy consumption). The system has been tested and applied successfully in Antarctic coastal waters (Terra Nova Bay, Ross Sea) in the framework of the Italian Research Programme in Antarctica (PNRA). The analytical possibilities allowed by the large amount of SPM which can be collected by FIS500 (50-100 mg) include total metal concentration, solid speciation and morphological investigation by scanning electron microscopy.

  17. Particle size distributions and organic-inorganic compositions of suspended particulate matters around the Bohai Strait

    Wang, Xiao; Bian, Changwei; Bi, Rong; Jiang, Wensheng; Zhang, Hua; Zhang, Xueqing


    Laser in situ scattering and transmissometry (LISST) significantly improves our ability to assess particle size distribution (PSD) in seawater, while wide-ranging measurements of the organic-inorganic compositions of suspended particulate matters (SPM) are still difficult by using traditional methods such as microscopy. In this study, PSD properties and SPM compositions around the Bohai Strait (China) were investigated based on the measurements by LISST in combination with hydro-biological parameters collected from a field survey in summer 2014. Four typical PSD shapes were found in the region, namely right-peak, left-peak, double-peak and negative-skew shapes. The double-peak and negative-skew shapes may interconvert into each other along with strong hydrodynamic variation. In the upper layer of the Bohai Sea, organic particles were in the majority, with inorganic particles rarely observed. In the bottom layer, SPM were the mixture of organic and inorganic matters. LISST provided valuable baseline information on size-resolved organic-inorganic compositions of SPM: the size of organic particles mainly ranged from 4 to 20 μm and 40 to 100 μm, while most SPM ranging from 20 to 40 μm were composed of inorganic sediment.

  18. The distribution and characteristics of suspended particulate matter in the Chukchi Sea

    WANG Weiguo; FANG Jianyong; CHEN Lili; WU Risheng; YU Xingguang


    Samples taken from the Chukchi Sea (CS) during the 4th Chinese National Arctic Research Expedition, 2010, were analyzed to determine the content and composition of suspended particulate matter (SPM) to improve our understanding of the distribution, sources and control factors of the SPM there. The results show that the SPM in the water column is highest in the middle and near the bottom in the south and central-north CS, followed by that off the Alaskan coast and in Barrow Canyon. The SPM content is lowest in the central CS. Scanning electron microscope (SEM) analysis shows that the SPM in the south and central-north CS is composed mainly of diatoms, but the dominant species in those two areas are different. The SPM off the Alaskan coast and in Barrow Canyon is composed mainly of terrigenous material with few bio-skeletal clasts. The distribution of temperature and salinity and the correlation between diatom species in SPM indicate that the diatom dominant SPM in the south CS is from the Pacific Ocean via the Bering Strait in summer. The diatom dominant SPM in the central-north CS is also from Pacific water, which reaches the CS in winter. The SPM in the middle and near the bottom of the water column off the Alaskan coast and in Barrow Canyon is from Alaskan coastal water and terrigenous material transported by rivers in Alaska.

  19. Five year studies on suspended particulate matter and heavy metals trends in Brass City of India.

    Mahima; Pal, Raina; Singh, D; Tripathi, Anamika; Singh, G S


    Moradabad is historically an important city of western Uttar Pradesh which is popularly known as Brass City of India, as about one thousand large and small scale brassware industries are located in and around the city. Suspended Particulate Matter (SPM) was collected two times in a week using High Volume Samplers (HVS) at six selected sites representing different areas of the city. The result indicates the annual and seasonal variations of SPM from 2005-2010. The highest value (869 μg/m3) was recorded at industrial site, i.e. Mughalpura in June (2008-09) while lowest value (71 μg/m3) at PTC in the month of July (2005-06). Five heavy metals, i.e. Cu, Zn, Fe, Cd and Pb were also observed at all the sites. Among the metals highest concentration of Zn were recorded at almost all the sites whereas Cu and Zn were found at industrial site, may be attributed to melting of Brass silly to prepare the different Brassware items. Pb and Cd were abundant at commercial site, located nearby Railway station as traffic density remains high during the day and night.

  20. Investigation of the kinetics of oil-suspended particulate matter aggregation.

    Sun, Juan; Zhao, Dongfeng; Zhao, Chaocheng; Liu, Fang; Zheng, Xilai


    The process of oil-suspended particulate matter aggregation (OSA) has been recognized by the oil spill remediation community to enhance the natural cleansing of oiled shorelines. A laboratory study was conducted to investigate the kinetics of OSA formation under various mixing intensities using the standard reference material 1941b and Arabian heavy crude oil. The results showed that formation of OSAs increased exponentially with mixing time and reached a maximum within 5h. The maximum oil trapping efficiency increased from 24% to 47%, and the required shaking time decreased from 4.5 to 1.2h as the sediment concentration and mixing energy increased. The maximum oil-to-sediment ratio reached 0.24-0.68 g oil/g sediment within 5h. Most of the formed OSAs were solid OSAs and single droplet OSAs with low mixing energies, and multi-droplet OSAs with high mixing energies. The sizes of the dispersed oil droplets and OSAs were also investigated.

  1. Laboratory investigation of oil-suspended particulate matter aggregation under different mixing conditions.

    Sun, Juan; Khelifa, Ali; Zhao, Chaocheng; Zhao, Dongfeng; Wang, Zhendi


    Oil-suspended particulate matter aggregation (OSA) has been recognized by the oil spill remediation community to effectively enhance the cleansing of spilled oil in the marine environment. While studies have investigated the application of mineral fines as an effective method to facilitate oil dispersion, decision-makers still lack information on the role of mixing energy in OSA formation and its significance to oil dispersion in real spills. This work studied the effect of level and duration of mixing energy on OSA formation using the standard reference material 1,941 b and Arabian light crude oil. The results showed that dispersed small oil droplets increased with an increase of both the level and duration of mixing energy to form multi-droplet OSAs. The sizes of the dispersed droplets varied between 5 and 10 μm under different conditions studied. The maximum oil trapping efficiency increased from 23% to 33%, the oil to sediment ratio increased from 0.30 to 0.43 g oil/g sediment, and the required shaking time decreased from 2.3 to 1.1h as the shaking rate increased from 2.0 to 2.3 Hz. Based on the size measurement results, a breakage effect on the formed OSAs and sediment flocs was confirmed under high mixing energy level.

  2. Land-use impacts on fatty acid profiles of suspended particulate organic matter along a larger tropical river

    Boëchat, Iola; Krüger, Angela; Chavez, R.C.;


    . Here, we analyzed land-use effects on the fatty acid (FA) composition and concentrations in suspended particulate organic matter (SPOM) along a fourth-order tropical river, the Rio das Mortes. Thereby, we aimed at testing the potential of fatty acids in riverine suspended particulate organic matter......Land-use change, such as agricultural expansion and urbanization, can affect riverine biological diversity and ecosystem functioning. Identifying the major stressors associated with catchment land-use change is a prerequisite for devising successful river conservation and restoration strategies...... of urban land-use impacts on larger tropical rivers. High total FA concentrations in the SPOM of urbanized tropical rivers may represent high-energy biochemical subsidies to food webs, potentially leading to changes in functional ecosystem characteristics, such as bacterial and suspension-feeder production....

  3. 40 CFR Appendix G to Part 50 - Reference Method for the Determination of Lead in Suspended Particulate Matter Collected From...


    ... of Lead in Suspended Particulate Matter Collected From Ambient Air G Appendix G to Part 50 Protection... SECONDARY AMBIENT AIR QUALITY STANDARDS Pt. 50, App. G Appendix G to Part 50—Reference Method for the..., 1000 µg Pb/ml in HNO3. Dissolve 1.598 g of Pb(NO3)2 in 0.45 M HNO3 contained in a 1 l volumetric flask...

  4. Spatial and temporal distribution of metals in suspended particulate matter of the Kali estuary, India

    Suja, S.; Kessarkar, Pratima M.; Fernandes, Lina L.; Kurian, Siby; Tomer, Arti


    Major (Al, Fe, Mn, Ti, Mg) and trace (Cu, Zn, Pb, Cr, Ni, Co, Zr, Rb, Sr, Ba, Li, Be, Sc, V, Ga, Nb, Mo, Sn, Sb, Cs, Hf, Ta, Bi, Th, U) elements and particulate organic carbon (POC) concentrations in surface suspended particulate matter (SPM) of the Kali estuary, (central west coast of India) were studied during the pre-monsoon, monsoon and post monsoon seasons to infer estuarine processes, source of SPM and Geoaccumulation Index (Igeo) assigned pollutionIgeo levels. Distribution of SPM indicates the presence of the estuarine turbidity maximum (ETM) during all three seasons near the river mouth and a second ETM during the post monsoon time in the upstream associated with salinities gradient. The SPM during the monsoon is finer grained (avg. 53 μm), characterized by uniformly low normalized elemental concentration, whereas the post and pre monsoon are characterized by high normalized elemental concentration with coarser grain size (avg. 202 μm and 173 μm respectively) with highest ratios in the upstream estuary. The elemental composition and principal component analysis for the upstream estuary SPM support more contribution from the upstream catchment area rocks during the monsoon season; there is additional contribution from the downstream catchment area during the pre and post monsoon period due to the tidal effect. The Kali estuarine SPM has higher Al, Fe, Mn, Ti, Mg, Ni, Co, Ba, Li and V with respect to Average World River SPM (WRSPM). Igeo values for the SPM indicate Kali Estuary to be severely enriched with Mn and moderately enriched with Cu, Zn, Ni, Co, U and Mo in the upstream estuary during pre and post monsoon seasons. Seasonal changes in salinity gradient (reduced freshwater flow due to closing of the dam gates), reduced velocity at meandering region of the estuary and POC of 1.6-2.3% resulted in co-precipitation of trace elements that were further fortified by flocculation and coagulation throughout the water column resulting in metal trapping in the

  5. Suspended Particulates Concentration (PM10 under Unstable Atmospheric Conditions over Subtropical Urban Area (Qena, Egypt

    M. El-Nouby Adam


    Full Text Available The main purpose of this study is to evaluate the suspended particulates (PM10 in the atmosphere under unstable atmospheric conditions. The variation of PM10 was investigated and primary statistics were employed. The results show that, the PM10 concentrations values ranged from 6.00 to 646.74 μg m−3. The average value of PM10 is equal to 114.32 μg m−3. The high values were recorded in April and May (155.17 μg m−3 and 171.82 μg m−3, respectively and the low values were noted in February and December (73.86 μg m−3 and 74.05 μg m−3, respectively. The average value of PM10 of the hot season (125.35 × 10−6 g m−3 was higher than its value for the cold season (89.27 μg m−3. In addition, the effect of weather elements (air temperature, humidity and wind on the concentration of PM10 was determined. The multiple R between PM10 and these elements ranged from 0.05 to 0.47 and its value increased to reach 0.73 for the monthly average of the database used. Finally, the PM10 concentrations were grouped depending on their associated atmospheric stability class. These average values were equal to 122.80 ± 9 μg m−3 (highly unstable or convective, 109.37 ± 12 μg m−3 (moderately unstable and 104.42 ± 15 μg m−3 (slightly unstable.

  6. Quantitative exposure matrix for asphalt fume, total particulate matter, and respirable crystalline silica among roofing and asphalt manufacturing workers.

    Fayerweather, William E; Trumbore, David C; Johnson, Kathleen A; Niebo, Ronald W; Maxim, L Daniel


    This paper summarizes available data on worker exposures to asphalt fume (soluble fraction), total particulate matter, and respirable crystalline silica (quartz) [hereinafter RCS] over a 30-year period in Owens Corning's asphalt production and roofing manufacturing plants. For the period 1977 through 2006, the air-monitoring database contains more than 1,400 personal samples for asphalt fume (soluble fraction), 2,400 personal samples for total particulate, and 1,300 personal samples for RCS. Unique process-job categories were identified for the asphalt production and roofing shingle manufacturing plants. Quantitative exposures were tabulated by agent, process-job, and calendar period to form an exposure matrix for use in subsequent epidemiologic studies of the respiratory health of these workers. Analysis of time trends in exposure data shows substantial and statistically significant exposure reductions for asphalt fume (soluble fraction), total particulate matter, and respirable crystalline silica at Owens Corning plants. Cumulative distribution plots for the most recent sampling period (2001-2006) show that 95% of the asphalt fume (soluble fraction) measurements were less than 0.25 mg/m3; 95% of the total particulate measurements were less than 2.2 mg/m3; and 95% of the RCS measurements were less than 0.05 mg/m3. Several recommendations are offered to improve the design of future monitoring efforts.

  7. River Suspended Sediment and Particulate Organic Carbon Transport in Two Montane Catchments in the Luquillo Critical Zone Observatory of Puerto Rico over 25 years: 1989 to 2014

    Clark, K. E.; Plante, A. F.; Willenbring, J. K.; Jerolmack, D. J.; Gonzalez, G.; Stallard, R. F.; Murphy, S. F.; Vann, D. R.; Leon, M.; McDowell, W. H.


    Physical erosion in mountain catchments mobilizes large amounts of sediment, while exporting carbon and nutrients from forest ecosystems. This study expands from previous studies quantifying river suspended sediment and particulate organic carbon loads in the Luquillo Critical Zone Observatory, in Puerto Rico. We evaluate the influences on river suspended load due to i) underlying basin geology, ii) hillslope debris and biomass supply, and iii) hurricanes and large storms. In the Mameyes and Icacos catchments of the Luquillo Mountains, we estimate suspended sediment and particulate organic carbon yields over a 25-year period using streamflow discharge determined from stage measurements at 15-intervals, with estimates of discharge replacing gaps in data, and over 3000 suspended sediment samples. We estimate variation in suspended sediment loads over time, and examine variation in particulate organic carbon loads. Mass spectrometry was used to determine organic carbon concentrations. We confirm that higher suspended sediment fluxes occurred i) in the highly weathered quartz diorite catchment rather than the predominantly volcaniclastic catchment, ii) on the rising limb of the hydrograph once a threshold discharge had been reached, and iii) during hurricanes and other storm events, and we explore these influences on particulate organic carbon transport. Transport of suspended sediment and particulate organic carbon in the rivers shows considerable hysteresis, and we evaluate the extent to which hysteresis affects particulate fluxes over time and between catchments. Because particulate organic carbon is derived from the critical zone and transported during high flow, our research highlights the role of major tropical storms in controlling carbon storage in the critical zone and the coastal ocean.

  8. Variability of suspended particulate matter concentrations and organic compounds in frontal zones of the Atlantic and Southern oceans

    Nemirovskaya, I. A.; Kravchishina, M. D.


    The concentrations of suspended particulate matter (SPM) and particulate forms of the organic compounds (hydrocarbons, lipids, and chlorophyll a) were determined in the surface water layers of the Atlantic and Southern oceans during February to May of 2012 and 2014. It was found that the distribution of concentrations of the studied components is mainly affected by the location of frontal zones. When ice cover forms in the Southern Ocean, the changes in water temperature and phytoplankton development at the ice-water interface result in an increase of the concentrations of SPM, chlorophyll a, and, to a lesser extent, of lipids and hydrocarbons in the surface water layer. The occasional sharp increase of hydrocarbon concentrations caused by anthropogenic pollution was registered at local parts of water areas in the east of the Atlantic Ocean, as well as in the North and Baltic seas.

  9. Pyrophaeophorbide-a as a tracer of suspended particulate organic matter from the NE Pacific continental margin

    Thomas S. Bianchi; Bauer, James E.; Druffel, Ellen R. M.; Lambert, Corey D


    Pyrophaeophorbide-a, a degradation product of chlorophyll-a, is predominantly formed by grazing processes in sediments as well as in the water column. Water column profiles of pyrophaeophorbide-a/suspended particulate organic carbon (SPOC) concentrations, at an abyssal site in the northeast (NE) Pacific (Sta M, 34°50′N, 123°00′W; 4100 m water depth), show low concentrations (0.01–0.1 ng/μg SPOC) at surface and mesopelagic depths, and increasing concentrations with closer proximity to the sea ...

  10. Seasonal variation of polychlorinated biphenyl congeners in surficial sediment, trapped settling material, and suspended particulate material in Lake Michigan, USA.

    Robinson, Sander D; Landrum, Peter F; Van Hoof, Patricia L; Eadie, Brian J


    A unique time series of surface sediment, trapped settling material, and suspended particulate material polychlorinated biphenyl (PCB) samples were collected at a 45-m deep site off Grand Haven (MI, USA) over a 14-month period. Both concentrations and congener distributions remained constant for the sediments, although there were seasonal and interannual variability in the other matrices. Trapped settling material and suspended particulate material PCB concentrations were substantially lower (~50%) in 1997 than in the samples from December 1997 through July 1998. The cause could not be determined from the data collected, but there were some very large storms during the winter-spring period of 1998, resulting in major sediment resuspension throughout the southern basin. Observed seasonal variation in PCB concentration and congener distribution on particles likely was due to the changes in particle composition. These include particle size and the source of particles (such as the amount of resuspended sediment in trapped settling material), and the role of diagenesis of the organic matter on particles.

  11. Suspended particulate layers and internal waves over the southern Monterey Bay continental shelf: an important control on shelf mud belts?

    Cheriton, Olivia M.; McPhee-Shaw, Erika E.; Shaw, William J.; Stanton, Timothy P.; Bellingham, James G.; Storlazzi, Curt D.


    Physical and optical measurements taken over the mud belt on the southern continental shelf of Monterey Bay, California documented the frequent occurrence of suspended particulate matter features, the majority of which were detached from the seafloor, centered 9–33 m above the bed. In fall 2011, an automated profiling mooring and fixed instrumentation, including a thermistor chain and upward-looking acoustic Doppler current profiler, were deployed at 70 m depth for 5 weeks, and from 12 to 16 October a long-range autonomous underwater vehicle performed across-shelf transects. Individual SPM events were uncorrelated with local bed shear stress caused by surface waves and bottom currents. Nearly half of all observed SPM layers occurred during 1 week of the study, 9–16 October 2011, and were advected past the fixed profiling mooring by the onshore phase of semidiurnal internal tide bottom currents. At the start of the 9–16 October period, we observed intense near-bed vertical velocities capable of lifting particulates into the middle of the water column. This “updraft” event appears to have been associated with nonlinear adjustment of high-amplitude internal tides over the mid and outer shelf. These findings suggest that nonlinear internal tidal motions can erode material over the outer shelf and that, once suspended, this SPM can then be transported shoreward to the middle and shallow sections of the mud belt. This represents a fundamental broadening of our understanding of how shelf mud belts may be built up and sustained.

  12. Determination of polyfluoroalkyl compounds in water and suspended particulate matter in the river Elbe and North Sea, Germany



    The distribution ofpolyfluoroalkyl compounds (PFCs) in the dissolved and particulate phase and their discharge from the river Elbe into the North Sea were studied. The PFCs quantified included C4-C8 perfluori hated sulfonates (PFSAs), 6:2 fluorotelomer sulfonate (6: 2FTS), C6 and C8 perfluorinated sulfinates (PFSiAs), C4-C12 perfluorinated carboxylic acids (PFCAs), perfluoro3,7-dimethyl-octanoic acid (3,7m2-PFOA), perfluorooctane sulfonamide (FOSA), and n-ethyl perfluroctane sulfonamidoethanol (EtFOSE). PFCs were mostly distributed in the dissolved phase, where perfluorooctanoic acid (PFOA) dominated with 2.9-12.5 ng/L. In the suspended particulate matter FOSA and perftuorooctane sulfonate (PFOS) showed the highest concentrations (4.0 ng/L and 2.3 ng/L, respectively). The total flux of ∑PFCs from the river Elbe was estimated to be 802kg/year for the dissolved phase and 152kg/year for the particulate phase. This indicates that the river Elbe acts as a source of PFCs into the North Sea. However, the concentrations of perfluorobutane sulfonate (PFBS) and perfluorobutanoic acid (PFBA) in the North Sea were higher than that in the river Elbe, thus an alternative source must exist for these compounds.

  13. Comparative Analysis of Indoor Levels of Suspended Particulates and Nitrogen Dioxide a Few Hours later after an Asthmatic Attack

    UKPEBOR Emmanuel Ehiabhi; OKUO James Majebi; EKANEM Victor James; UKPEBOR Justina Ebehirieme


    Suspended particulates (TSP) and nitrogen dioxide (NO2) are known respiratory irritants linked to asthma aggravation. This pilot study was designed to investigate the role of these pollutants on the frequency of asthmatic attack on two of the inhabitants of a household. The surveillance of TSP and NO2 in this household commenced a few hours later, after one of the occupants suffered an attack. The TSP load determination was done using a High Volume Gravimetric sampler and a light scattering method via a Haz-Dust 10 μm particulate monitor. Palmes Diffusion tubes for NO2 and a portable Crowcon Gasman toxic gas detector were utilized for NO2 screening. In the first day of monitoring in the living room, the in situ particulate sampler (Haz-Dust) recorded a mean TSP level of 26,000the Gasman toxic gas detector for NO2, the NO2 concentration for the first few hours of sampling was lower than 188 μgom-3, the detection limit of this instrument. However, the exact NO2 concentrations for the 7 day monitoring tubes.

  14. Particulate matter from re-suspended mineral dust and emergency cause-specific respiratory hospitalizations in Hong Kong

    Pun, Vivian C.; Tian, Linwei; Ho, Kin-fai


    While contribution from non-exhaust particulate matter (PM) emissions towards traffic-related emissions is increasing, few epidemiologic evidence of their health impact is available. We examined the association of short-term exposure to PM10 apportioned to re-suspended mineral dust with emergency hospitalizations for three major respiratory causes in Hong Kong between 2001 and 2008. Time-series regression model was constructed to examine association of PM10 from re-suspended mineral dust with emergency hospitalizations for upper respiratory infection (URI), chronic obstructive pulmonary disease (COPD) and asthma at exposure lag 0-5 days, adjusting for time trends, seasonality, temperature and relative humidity. An interquartile range (6.8 μg/m3) increment in re-suspended mineral dust on previous day was associated with 0.66% (95% CI: 0.12, 0.98) increase in total respiratory hospitalizations, and 1.01% (95% CI: 0.14, 1.88) increase in URI hospitalizations. A significant 0.66%-0.80% increases in risk of COPD hospitalizations were found after exposure to re-suspended mineral dust at lag 3 or later. Exposure to mineral dust at lag 4 was linked to 1.71% increase (95% CI: 0.14, 2.22) in asthma hospitalizations. Associations from single-pollutant models remained significant in multi-pollutant models, which additionally adjusted for PM10 contributing from vehicle exhaust, regional combustion, residual oil, fresh sea salt, aged sea salt, secondary nitrate and secondary sulfate, or gaseous pollutants (i.e., nitrogen dioxide, sulfur dioxide, or ozone), respectively. Our findings provide insight into the biological mechanism by which non-exhaust pollution may be associated with risk of adverse respiratory outcomes, and also stress the needs for strategies to reduce emission and re-suspension of mineral dust. More research is warranted to assess the health effects of different non-exhaust PM emissions under various roadway conditions and vehicle fleets.

  15. Distribution of suspended particulate matter in the waters of eastern continental margin of India

    Rao, Ch.M.

    Distribution of total suspended matter (TSM) in surface and near bottom (approximately 5 m above sea bed) waters reveals a wide variation in concentration and composition. TSM varies from 0.05 to 122 mg.l/1 in surface waters, and from 0.25 top 231...

  16. 42 CFR 84.1157 - Chemical cartridge respirators with particulate filters; performance requirements; general.


    ... APPROVAL OF RESPIRATORY PROTECTIVE DEVICES Dust, Fume, and Mist; Pesticide; Paint Spray; Powered Air... following minimum requirements for performance and protection: (a) Breathing resistance test. (1) Resistance...) The maximum allowable resistance requirements for chemical cartridge respirators are as...

  17. Individual particle analysis of coarse air suspended particulate material by synchrotron radiation X-ray micro fluorescence

    Moreira, Silvana; Melo Junior, Ariston [Universidade Estadual de Campinas, SP (Brazil). Faculdade de Engenharia Civil, Arquitetura e Urbanismo. Dept. de Recursos Hidricos]. E-mail:; Perez, Carlos Alberto [Laboratorio Nacional de Luz Sincrotron (LNLS), Campinas, SP (Brazil)]. E-mail:; Vives, Ana Elisa S. de [Universidade Metodista de Piracicaba (UNIMEP), Santa Barbara D' Oeste, SP (Brazil). Faculdade de Engenharia, Arquitetura e Urbanismo]. E-mail:; Nascimento Filho, Virgilio F. [Centro de Energia Nuclear na Agricultura (CENA), Piracicaba, SP (Brazil). Lab. de Instrumentacao Nuclear]. E-mail:


    The purpose of this work is evaluate the size of individual particles present in the air suspended particulate material collected in Campinas, Sao Paulo State, and analyze quantitatively the particles using the synchrotron radiation X-ray micro fluorescence ({mu}-SRXRF) associated with the fundamental parameter method to correct attenuation/absorption effects by the matrix. The particles analyzed have size between 50-10 {mu}m and to perform the spatial distribution a white beam of synchrotron radiation condensed by a conical capillary (13 {mu}m diameter) was used. For the quantitative analysis punctual measures in thin films standards in Mylar subtract were performed. The elements detected were Si, S, Cl, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Ba and Pb. (author)

  18. Observations on suspended particulate matter (SPM) and microalgae in the Dollard Estuary, The Netherlands: Importance of late winter ice cover of the intertidal flats

    Staats, N.; De Deckere, E.; Kornman, B.; van der Lee, W.; Termaat, R.; Terwindt, J.; de Winder, B.


    Three years of combined physical and biological measurements in the Dollard tidal basin showed that in the early spring of 1996, suspended particulate matter (SPM) concentrations were low compared to observations in spring 1995 and 1997. Since in 1996 the duration of ice formation on the tidal flats

  19. Characterization of Suspended Particulates in the Northern Gulf of Mexico from Ocean Color Remote Sensing


    particulate matters, as it not only affects subsurface light field (then photosynthesis ), it could also be a tracer of pollutant transport and an...derived by applying the Quasi-Analytical Algorithm (QAA) [Lee et ai, 2002], with derived total absorption and backscattering coefficients shown in Fig...4. Apparently, while the absorption image has some resemblance of the [SPM] spatial pattern, the backscattering image show enhanced scattering of

  20. Indoor and outdoor concentrations of Japanese cedar pollens and total suspended particulates: A case study at a kindergarten in Japan

    Yamamoto, Naomichi [Department of Nursing, School of Health Sciences, Tokai University, Bohseidai, Isehara-shi, Kanagawa 259-1193 (Japan); Japan Society for the Promotion of Science (JSPS), Ichiban-cho 8, Chiyoda-ku, Tokyo 102-8472 (Japan); Nishikawa, Junko; Sakamoto, Miho; Shimizu, Tomomi; Matsuki, Hideaki [Department of Nursing, School of Health Sciences, Tokai University, Bohseidai, Isehara-shi, Kanagawa 259-1193 (Japan)


    Japanese cedar pollinosis (JCP) caused by allergenic cedar and cypress pollens is one of major economic and health issues in Japan. The present study reported here aimed to provide basic data to understand the status of early life exposures to airborne cedar and cypress pollens in school settings. In particular, the study investigated relationships between indoor and outdoor concentrations of airborne cedar and cypress pollens and total suspended particulates (TSP) in a kindergarten in Japan. Overall, outdoor concentrations of the airborne pollens and TSP were higher than the indoor concentrations, i.e., indoor to outdoor (I/O) ratios of 0.043-0.055 and 0.545 for the airborne pollens and TSP, respectively. The smaller I/O ratios for the pollens were expected because the larger pollen grains (20-30 {mu}m in diameter) were less likely penetrated to indoor environment than for smaller airborne particulates. The present study also found increased TSP concentrations during the pollen season was likely attributed to increased airborne pollen concentrations. By understanding the status of indoor and outdoor concentrations of airborne cedar and cypress pollens in school settings, early life exposures to these allergenic pollens should be effectively minimized to prevent subsequent progression to JCP symptoms. (author)

  1. Distribution and geochemical composition of suspended particulate material in the shallow embayment of northern Thermaikos Gulf, Greece

    Tsompanoglou, K.; Anagnostou, Ch.; Krasakopoulou, E.; Pagou, K.; Karageorgis, A. P.; Pavlidou, A.; Albanakis, K.; Tsirambides, A.


    The distribution and the chemical composition of Suspended Particulate Matter (SPM), in the northern Thermaikos Gulf, were studied during an annual experiment, carried out from June 2004 to June 2005. Water samples were collected at three depths (1 m below surface, 10 m depth, and 2 m above bottom) and filtered to obtain SPM, particulate organic carbon (POC), total particulate nitrogen (PNtot) and particulate phosphorus (PP) concentrations. SPM and POC concentrations exhibited strong spatial and temporal variations, related to the different environmental characteristics in the study area such as river network, biological productivity, anthropogenic interferences, wind regime, and resuspension of the bottom sediments. The highest SPM concentrations were recorded at the surface (mean = 1.45 ± 0.75 mg/l, maximum value = 11.60 mg/l) and close to the bottom (mean = 1.49 ± 0.67 mg/l, maximum value = 11.72 mg/l), creating surface and bottom nepheloid layers (SNL and BNL), respectively. The maximum values were recorded close to the river mouths; the rivers are identified as the major sources of SPM. The Axios and Aliakmon rivers supplied the gulf with particulate matter, during the entire sampling period. Chemical analysis has revealed the significant correlation among the elements Al, Si, Fe, Ti, K, V, Mg and Ba suggesting the presence of terrigenous aluminosilicate minerals. Silica and Ca have terrigenous origin, but also come from autochthonous biogenic fraction. Chromium, Ni and Co, are of natural origin and derived from mafic and ultramafic rocks of the Axios and Aliakmon watersheds. Copper and Zn are correlated with each other and their distributions follow that of POC; these two metals are derived from partially treated domestic and industrial effluents. The vertical distribution of organic matter implies increased primary production within the upper layer of the water column. Phosphorus is present mainly in an organic form. During the sampling period, the water

  2. Amino sugars in suspended particulate matter from the Bay of Bengal during the summer monsoon of 2001

    Loreta Fernandes; Fraddry D’Souza; S G P Matondkar; Narayan B Bhosle


    Amino sugars (AS)are important constituents of organic matter.However,very little is known about their cycling in marine waters.In this research,we assessed the distribution and cycling of these compounds in waters of the Bay of Bengal.For this purpose,samples of suspended particulate matter (SPM)were collected from 8 depths (surface to 1000 m)at 6 locations during the 166th cruise of the ORV Sagar Kanya in the Bay of Bengal in July/August 2001.The SPM samples were analysed for particulate organic carbon (POC),particulate nitrogen (PN)and AS concentrations and composition.The AS varied between 0.4 and 17.5 nmol/l.Concentrations were high in the surface waters and generally decreased with increasing depth.AS concentration decreased from the south to north.AS accounted for 0.01 to 0.71%and 0.05 to 2.37%of POC and PN,respectively. Rapid decrease in AS-C%and AS-N%with depth indicates that these compounds were preferentially degraded relative to bulk POC and PN.The composition of AS suggests that glucosamine (GLU-N)and galactosamine (GAL-N)were present in the surface SPM samples,and their abundance decreased from surface downwards.Relatively,low values of GLU-N/GAL-N ratio indicate that the organic matter was mostly derived from the detritus of micro-organisms.Our data suggest that chitin,a polymer of the glucosamine produced by many marine organisms was not the major source of AS in the Bay.Rapid cycling of these compounds indicates their importance in the cycling of nitrogen in marine waters.

  3. Phytoavailability and speciation of aluminum carried by total suspended particulates (TSP) to Masson pine ( Pinus massoniana L.)

    Wang, Shuiliang; Wang, Ping; Fan, Chinbay Q.; Xu, Hui


    Aluminum (Al) is an abundant metal in airborne particulate matter. Al concentrations carried by total suspended particulates (TSP) of the Nanjing atmosphere were distinctly higher in soils of industrial areas than the background concentration of the soils. This study aimed to assess the influence of the soils varying in their degree of contamination on the soil-to-plant transfer and translocation of Al to Masson pine ( Pinus massoniana L.). A pot experiment was conducted to investigate the phytoavailability and speciation of Al carried by TSP which was collected at urban and industrial sites over a 12-month period in the atmosphere of Nanjing, China. The extractable noncrystalline Al in environmental particulate samples could be operationally fractionated into insoluble (Alin), oxide (Alox), organic (Alor), carbonate (Alca), and exchangeable species (Alex) using Tessier's sequential extraction procedure. The results showed that relatively high Al concentrations in TSP and soil samples were observed at the industrial site due to emissions from a local industry that manufactures Al-based products. The distribution sequence of Al species was quite similar for TSP and soil samples, which was Alin > Alor > Alox > Alca > Alex. The order of industrial particulate matter (IPM) was Alin > Alox > Alca > Alex > Alor. Alor was not detectable. A greater migration of Alex species entered the pine roots and the highest Al contents were accumulated in the roots and declined in the aerial portions. The soil-to-pine Al transfer was extremely low even when grown on industrial Al-contaminated soils. A significant positive correlation was found between the Al contents in pine seedlings and rhizospheric Alex contents. In contrast, there was a strong negative correlation between rhizospheric Alex contents and seedling biomass. For the spiked soils, under the influence of IPM, Al phytoavailability decreased with elevated rhizospheric Al and Alex. Collectively, this study provided evidence

  4. Suspended particulate variations and mass size distributions of incense burning at Tzu Yun Yen temple in Taiwan, Taichung.

    Fang, Guor-Cheng; Chang, Cheng-Nan; Wu, Yuh-Shen; Yang, Chang-Ju; Chang, Shyh-Chyi; Yang, I-Lin


    Ambient suspended particulate concentrations were measured at Tzu Yun Yen temple in this study. This is characteristic place of incense burning and indoor air pollution sampling site. A universal sampler, micro-orifice uniform deposited impactor (MOUDI) sampler and dry deposition plate were used to measure particulate concentrations. Tzu Yun Yen temple is a typical famous Buddhist-Taoist combined temple, where many pilgrims come from different areas and various belief systems indicating the eclecticism of the temple. The average number of people visiting this temple is above 5000 per day. The PM2.5/PM10 ratios ranged between 31.2 and 87.4% and averaged 69.6+/-12.3% during the incense-burning period, respectively. The results also demonstrated that the fine particulates concentrations (PM2.5) constituted the majority of indoor-suspended particulates at Tzu Yun Yen temple. PM10 concentration was 110.1 microg m(-3) for Zhong Yuan Jie (A festival on the seventh full moon in a lunar year, otherwise known as a summer lantern festival and (or) the commemoration of the dead. Almost all temples have maximum pilgrims for the commemoration of the dead on this day.) and the 1st or 15th of nong li (Nong li is a Chinese lunar calendar system in which 1 year is divided into fixed periods, and the beginning and end of a year is determined. The new moon and full moon are the 1st and 15th, respectively of each month in the Chinese lunar calendar. Many pilgrims appeared at each temple for blessing and good luck for themselves on the 1st and 15th of each Chinese lunar month.) with numbers higher than non-Zhong Yuan Jie and non-1st or -15th day of nong li (average = 85.5 microg m(-3)). In general, the average dry deposition flux (49.4 mg m(-2) day(-1)) in the indoor environment is lower than those measured in the outdoor environment (184.0 mg m(-2) day(-1)) in this study. The mean dry deposition flux of indoor/outdoor ratio was 46.2%. The average mass size distributions were bimodal

  5. Simple statistical formulas for estimating biogeochemical properties of suspended particulate matter in the southern Baltic Sea potentially useful for optical remote sensing applications

    Sławomir B. Woźniak


    Full Text Available Simple statistical formulas for estimating various biogeochemical properties of suspended particulate matter in the southern Baltic Sea are presented in this paper. These include formulas for estimating mass concentrations of suspended particulate matter (SPM, particulate organic matter (POM, particulate organic carbon (POC and total chlorophyll a (Chl a. Two different approaches have been adopted. The first approach was to use the available empirical material (the results of field measurements and laboratory analyses of discrete water samples and find statistical formulas for estimating the biogeochemical properties of suspended particulate matter from those of inherent optical properties (IOPs, which are potentially retrievable from remote sensing measurements. The second approach was to find formulas that would enable biogeochemical properties of suspended particulate matter to be estimated directly from spectral values of the remote-sensing reflectance Rrs. The latter was based on statistical analyses of a synthetic data set of Rrs obtained from numerical simulations of radiative transfer for which the available empirical material on seawater IOPs and biogeochemistry served as input data. Among the empirical formulas based on seawater IOPs that could be used as a step in two-stage remote sensing algorithms (the other step is estimating certain IOPs from reflectance, the best error statistics are found for estimates of SPM and POM from the particulate backscattering coefficient bbp in the blue region of light wavelengths (443 nm, and for estimates of POC and Chl a from the coefficient of light absorption by the sum of all non-water (i.e. suspended and dissolved constituents of seawater an, in the blue (443 nm and green (555 nm parts of the spectrum respectively. For the semi-empirical formulas under consideration, which could serve as starting points in the development of local one-stage (direct remote sensing algorithms, the best error

  6. Effect of the resuspension technique on distribution of the heavy metals in sediment and suspended particulate matter.

    Pourabadehei, Mehdi; Mulligan, Catherine N


    Harbour areas play important roles in the economy worldwide. Human activities, however, in those areas, generate contamination, which mostly accumulates in sediments. On the other hand, harbour areas have been facing deposition of significant amounts of sediment each year. As a consequence, shallowness and accumulation of contaminants in sediment become challenging issues in harbours. Among the various management options for remediation of contaminated sediments in harbours, resuspension technique was introduced as a new approach to address those issues. The concept of the resuspension method is that finer sediments have a greater tendency to adsorb the contamination. Therefore, removing the finer sediments instead of dredging the whole contaminated area is the main goal of the resuspension technique. The objective of this paper was to evaluate the effect of the resuspension method on reducing the concentration of contamination and distribution of heavy metals in sediment and suspended particulate matter. The resuspension method was successful in reducing the concentration of seven selected heavy metals (Cr, Ni, Cu, Zn, As, Cd and Pb) by removing just 4% of the contaminated sediment. The contamination intensity in the sediment, presented by geoaccumulation index, was reduced for Cd and Pb as the main contaminants by 26 and 28 percent and the rest of the selected heavy metals returned to the natural level. The results of the sequential extraction tests and enrichment factor implied that the resuspension technique is capable of decreasing the risk of remobilization of heavy metals in the aquatic ecosystem.

  7. Chemical composition of total suspended particulates (TSP) and trace gases near a super thermal power plant (Shaktinagar) U.P.

    Tiwari, S.; Singh, G.; Chatterjee, R.N.; Upadhyaya, V. [Rain and Cloud Physics Research Centre (IITM), New Delhi (India)


    Total suspended particulates (TSP) and its chemical composition as well as concentrations of trace gases (i.e. SO{sub 2}, NO{sub 2}, NH{sub 3} ad O{sub 3}) sampled near Singrauli super coal-fired power plant situated at Shaktinagar in U.P were investigated. The sampling site is situated at a distance of 1 km north of the power plant and the samples were collected during the monsoon seasons of 1991 and 1992. The concentration of TSP has been found to be higher in 1991 than in 1992. This is attributed to the prevailing wind direction which were mainly north and north easterly in 1991 and carried more TSP from coal mines situated in the north. Out of the eight major water soluble ionic components of TSP measured (i.e. Cl, SO{sub 4}, NO{sub 3}, NH{sub 4}, Na, K, Ca and Mg), concentrations of soil oriented aerosols, especially Ca and concentration of SO{sub 4} which is emitted from thermal power plant have been found to be dominant. Analysis of trace gases showed that the concentrations of SO{sub 2} and NH{sub 3} are much higher as compared to the concentrations of NO{sub 2} and O{sub 3}. 9 refs., 3 tabs.

  8. Polycyclic Aromatic Hydrocarbons and n-alkanes in Suspended Particulate Matter and Sediments from the Langat River, Peninsular Malaysia

    Alireza Riyahi Bakhtiari


    Full Text Available The Langat River basin has seen rapid developments in industrialization, urbanization and dramatic population increases during the past two decades. The composition and sources of polycyclic aromatic hydrocarbons (PAHs and aliphatic hydrocarbon (n-alkanes concentrations were determined in surface sediments (SS and suspended particulate matter (SPM collected from six locations in the Langat River. The total n-alkanes concentrations (∑HC ranged from 5900 to 23000 µg/g in SPM and 1700 to 8600 µg/g in SS samples. Total PAHs concentrations varied from 306 to 7968 ng/g in SPM and 558 to 980 ng/g in SS. PAHs and n-alkanes were dominated by higher molecular weight compounds in SS and low-medium molecular weight compounds in SPM. Carbon preference index (CPI values for n-alkanes in ranges C 25-33, C 15-35 and C 25-35 varied from 0.95 to 2.49 in SS and close to unity in SPM. The CPIs values indicated multiple n-alkanes sources (petrogenic and natural. PAHs isomer pairs ratios indicated multiple (petrogenic and pyrogenic with predominance of pyrogenic PAH sources. Analysis of the possible source of PAHs and n-alkanes indicated a complicated, combined PAHs and n-alkanes source in the Langat River.

  9. Atmospheric Correction of Satellite GF-1/WFV Imagery and Quantitative Estimation of Suspended Particulate Matter in the Yangtze Estuary

    Pei Shang


    Full Text Available The Multispectral Wide Field of View (WFV camera on the Chinese GF-1 satellite, launched in 2013, has advantages of high spatial resolution (16 m, short revisit period (4 days and wide scene swath (800 km compared to the Landsat-8/OLI, which make it an ideal means of monitoring spatial-temporal changes of Suspended Particulate Matter (SPM in large estuaries like the Yangtze Estuary. However, a lack of proper atmospheric correction methods has limited its application in water quality assessment. We propose an atmospheric correction method based on a look up table coupled by the atmosphere radiative transfer model (6S and the water semi-empirical radiative transfer (SERT model for inversion of water-leaving reflectance from GF-1 top-of-atmosphere radiance, and then retrieving SPM concentration from water-leaving radiance reflectance of the Yangtze Estuary and its adjacent sea. Results are validated by the Landsat-8/OLI imagery together with autonomous fixed station data, and influences of human activities (e.g., waterway construction and shipping on SPM distribution are analyzed.

  10. Origin, composition and quality of suspended particulate organic matter in relation to freshwater inflow in a South Texas estuary

    Lebreton, Benoit; Beseres Pollack, Jennifer; Blomberg, Brittany; Palmer, Terence A.; Adams, Leslie; Guillou, Gaël; Montagna, Paul A.


    South Texas has a semi-arid climate with a large interannual variability of freshwater inflows. This study sought to define how changes in freshwater inflow affect the composition, quantity and quality of suspended particulate organic matter (SPOM) in a South Texas estuary: the Mission-Aransas estuary. The study was implemented 1.5 months after a large rain event in September 2010 and continued for 10 months of drought conditions. The composition of SPOM originating from rivers, the Gulf of Mexico and the estuary were determined using stable isotopes (δ13C, δ15N and δ34S). The quantity and quality of SPOM were assessed using organic carbon content, chlorophyll a concentrations and C/chl a ratios. Our results demonstrated that autochthonous phytoplankton was the dominant component of SPOM in the Mission-Aransas estuary during droughts. Benthic organic matter from local primary producers (i.e., seagrass, salt marsh plants, benthic microalgae) did not influence SPOM composition, either as fresh material or as detritus. A comparison with a positive estuary (i.e., Sabine-Neches estuary, TX) indicates that decreases in freshwater inflow may lead to decreases of terrestrial organic matter inputs and to increase the ratio of autochtonous phytoplanktonic material in SPOM.

  11. Short- and long-chain perfluoroalkyl substances in the water, suspended particulate matter, and surface sediment of a turbid river.

    Zhao, Pujun; Xia, Xinghui; Dong, Jianwei; Xia, Na; Jiang, Xiaoman; Li, Yang; Zhu, Yuemei


    Perfluoroalkyl substances (PFASs) have attracted attentions all around the world. However, little is known about their distribution among water, suspended particulate matter (SPM), and sediment phases in rivers, especially for the short-chain PFASs. In this work, the Yellow River, the largest turbid river in the world, was selected as a case to study eleven kinds of PFASs in the three phases of rivers. These PFASs included C4-C12 perfluorinated carboxylates (PFCAs), perfluorobutyl sulfonate (PFBS), and perfluorooctansulfonate (PFOS), among which C4-C7 PFCAs and PFBS belong to short-chain PFASs, while C8-C12 PFCAs and PFOS belong to long-chain PFASs. The results showed that the total PFAS concentration ranged from 44.7ngL(-1) to 1.52μgL(-1) in the water, from 8.19 to 17.4ngg(-1) in the sediment, and from 3.44 to 14.7ngg(-1) in the SPM. Short-chain PFASs predominated in the water and could reach up to 88.8% of the total PFAS concentration in water, while long-chain PFASs prevailed in the sediment and SPM. The PFAS concentration in SPM showed a significant negative correlation with SPM concentration in river water (pperfluoroalkyl chemicals from traditional long-chain ones to short-chain ones. Further studies should be conducted to evaluate the eco-environmental risks of these short-chain PFASs in water environments.

  12. Atmospheric Correction of Satellite GF-1/WFV Imagery and Quantitative Estimation of Suspended Particulate Matter in the Yangtze Estuary.

    Shang, Pei; Shen, Fang


    The Multispectral Wide Field of View (WFV) camera on the Chinese GF-1 satellite, launched in 2013, has advantages of high spatial resolution (16 m), short revisit period (4 days) and wide scene swath (800 km) compared to the Landsat-8/OLI, which make it an ideal means of monitoring spatial-temporal changes of Suspended Particulate Matter (SPM) in large estuaries like the Yangtze Estuary. However, a lack of proper atmospheric correction methods has limited its application in water quality assessment. We propose an atmospheric correction method based on a look up table coupled by the atmosphere radiative transfer model (6S) and the water semi-empirical radiative transfer (SERT) model for inversion of water-leaving reflectance from GF-1 top-of-atmosphere radiance, and then retrieving SPM concentration from water-leaving radiance reflectance of the Yangtze Estuary and its adjacent sea. Results are validated by the Landsat-8/OLI imagery together with autonomous fixed station data, and influences of human activities (e.g., waterway construction and shipping) on SPM distribution are analyzed.

  13. Distribution and sources of aliphatic and polycyclic aromatic hydrocarbons in suspended particulate matter in water from two Brazilian estuarine systems

    Maioli, Otávio L. G.; Rodrigues, Kamila C.; Knoppers, Bastiaan A.; Azevedo, Débora A.


    The levels of selected organic markers, including 17 polycyclic aromatic hydrocarbons (PAHs), 16 of which are classified as priority pollutants by the US-EPA and perylene, aliphatic hydrocarbons (total and linear alkanes) and petroleum biomarkers (hopanes and steranes), were measured in suspended particulate matter (SPM) of the Mundaú-Manguaba estuarine-lagoon system (MMELS) in northeastern Brazil and the Paraíba do Sul River (PSR) estuary in southeastern Brazil, both of which are affected by sugarcane agriculture and urbanization. A total of 33 surface water samples of SPM were collected (22 from the MMELS and 11 from the PSR). The ∑16PAH ranged from 221 to 1243 ng g -1 in the MMELS and from 228 to 1814 ng g -1 in the PSR. Hopane and sterane concentrations in the PSR were higher than in the MMELS due to the input from petrogenic sources in PSR. The contributions of higher plants were also observed by n-alkane analyses. The PAH isomeric ratios indicated that the SPM from MMELS showed characteristics of combustion from biomass or petroleum and PSR was associated to petrogenic input, either from combustion or from unburned petroleum. Three sampling sites located near to the sugarcane plant and mouth of the rivers showed higher PAH concentrations and may largely be considered as highly contaminated. However, levels of n-alkanes and petroleum biomarkers in both study areas were relatively low.

  14. A Study on the Relationship Among Visibility, Atmospheric Suspended Particulate Concentration, and Meteorological Conditions in Hong Kong

    LEUNG Yin-kong; WU Man-chi; YEUNG King-kay


    By making use of the 2005 hourly data of visibility at Chek Lap Kok and suspended particulate (PM2.5) at Tung Chung, PM2.5 concentration and visibility (excluding cases with mist, fog, rain, or relative humidity,95%) are found to have a reciprocal relationship with correlation coefficient about 0.8. Besides, similar seasonal trends are exhibited in both the number of hours of reduced visibility (visibility below 8 km and excluding cases with mist, fog, rain, or relative humidity≥95%) and PM2.5 concentration, i.e., with higher value attained in winter and lower value in summer. Backward trajectory analysis using HYSPLIT indicates that this phenomenon is related to the source of air mass affecting Hong Kong. For continental trajectories, the average daily occurrence of reduced visibility and the daily mean PM2.5 concentration were much higher than the corresponding occurrence of reduced visibility and mean PM2.5 concentration for maritime trajectories. A case study on an event with a tropical cyclone approaching Hong Kong is included in this paper to demonstrate the significance of meteorological conditions in determining the visibility and PM2.5 concentration.

  15. Analysis of respirable particulate exposure and its effect to public health around lead smelter and e-waste processing industry in West Java, Indonesia

    Marselina, M.; Roosmini, D.; Salami, I. R. S.; Ayu A, M.; Cahyadi, W.


    Respirable particulate exposure strongly affects human health, especially for children who lived around industrial area. This study was conducted to evaluate the effect of respirable particulate exposure to lung capacity of children. Study location in this study was Parung Panjang District, area of lead smelter industry and also in Astana Anyar District, area of e-waste processing industry. Thirty children were involved in Astana Anyar District and also thirty children in Parung Panjang District. The control groups were also studied in both areas. Predicted average daily intake (ADD) of respirable particulate was estimated and lung or respiration condition of children was measured by using spirometer. The lung condition of respondents was estimated by FEV1.0 and FVC values. As the result, the predicted ADD of children in lead smelter area is 3 times higher than the predicted ADD of children in e-waste processing area. It was correlated positively with the higher PM2.5 concentration in Parung Panjang District than the PM2.5 concentration in Astana Anyar District. Metals concentration in Parung Panjang was also measured with X-Ray Fluorescence (XRF) in this study and it was clearly state that metals concentration in location study were higher than metals concentration in control area.

  16. Studi Kualitas Udara Melalui Pengamatan Tingkat Kandungan Suspended Particulate Matter(SPM) Dan Kimia Air Hujan (Kation Dan Anion) Di Kota Medan

    Novika, Sutri


    Telah dilakukan analisis terhadap kualitas udara di Kota Medan. Analisis didasarkan pada tingkat kandungan konsentrasi Suspended Particulate Matter (SPM) tahun 2001-2009 dan kandungan kimia air hujan antara rentang tahun 2009. Data diperoleh dari Badan Metereologi Klimatologi dan Geofisika (BMKG) Stasiun Sampali Medan. Analisis terhadap konsentrasi SPM meliputi analisis perbandingan tingkat kandungan konsentrasi SPM tiap tahunnya dengan acuan baku mutu (230 μgram/Nm3 ). Pengolahan data dilaku...

  17. Health effects of ambient levels of respirable particulate matter (PM) on healthy, young-adult population

    Shaughnessy, William J.; Venigalla, Mohan M.; Trump, David


    There is an absence of studies that define the relationship between ambient particulate matter (PM) levels and adverse health outcomes among the young and healthy adult sub-group. In this research, the relationship between exposures to ambient levels of PM in the 10 micron (PM10) and 2.5 micron (PM2.5) size fractions and health outcomes in members of the healthy, young-adult subgroup who are 18-39 years of age was examined. Active duty military personnel populations at three strategically selected military bases in the United States were used as a surrogate to the control group. Health outcome data, which consists of the number of diagnoses for each of nine International Classification of Diseases, 9th Revision (ICD-9) categories related to respiratory illness, were derived from outpatient visits at each of the three military bases. Data on ambient concentrations of particulate matter, specifically PM10 and PM2.5, were obtained for these sites. The health outcome data were correlated and regressed with the PM10 and PM2.5 data, and other air quality and weather-related data on a daily and weekly basis for the period 1998 to 2004. Results indicate that at Fort Bliss, which is a US Environmental Protection Agency designated non-attainment area for PM10, a statistically significant association exists between the weekly-averaged number of adverse health effects in the young and healthy adult population and the corresponding weekly-average ambient PM10 concentration. A least squares regression analysis was performed on the Fort Bliss data sets indicated that the health outcome data is related to several environmental parameters in addition to PM10. Overall, the analysis estimates a .6% increase in the weekly rate of emergency room visits for upper respiratory infections for every 10 μg/m3 increase in the weekly-averaged PM10 concentration above the mean. The findings support the development of policy and guidance opportunities that can be developed to mitigate exposures

  18. Behaviour of suspended particulate matter (SPM and selected trace metals during the 2002 summer flood in the River Elbe (Germany at Magdeburg monitoring station

    M. Baborowski


    Full Text Available In August 2002, in the worst flooding in more than 100 years, the River Elbe destroyed built-up areas and caused widespread erosion and the relocation of soils and river sediments. To assess the pollutants entering the water, surveys of dissolved constituents and suspended particulate matter (SPM were carried out daily during the flood at a monitoring station near Magdeburg. The sampling point is part of the network of the International Commission for the Protection of the Elbe (ICPE. The results were compared with those of previous flood studies which used the same sampling strategy. Unlike past floods, the 2002 flood was characterised by the transport of relatively fine suspended material with a low mass concentration. Owing to different input sources, the maxima of dry weight and of particle number concentration occurred at different times. Hg, Fe, Mn, Zn, Cu, Ni and Cr showed a maximum concentration concurrent with the dry weight of the SPM, whereas the maximum concentrations of As, Pb, and Cd coincided with the particle number concentration peak. The concentration of particulate matter decreased rapidly, unlike the concentrations of dissolved substances such as DOC and trace metals, as well as the values of UV extinction, all of which remained high for a longer period. Comparing the results of the 2002 flood with the winter floods in 1995, 1999 and 2000, revealed increased values of As and Pb as well as higher concentrations of dissolved compounds. Keywords: river, flood, transport, suspended particulate matter, trace metals, dissolved compounds, Elbe

  19. Microbial respiration activities correlated to sequentially separated, particulate and water-soluble organic matter fractions from arable and forest topsoils

    Kaiser, M.; Wirth, S.; Ellerbrock, R.; Sommer, M.


    Michael Kaiser1, Stephan Wirth2, Ruth H. Ellerbrock3, Michael Sommer3,4 1University of California Merced, Natural Science, 4225 N. Hospital Rd., Atwater, CA 95301 2,3 Leibniz-Center for Agricultural Research (ZALF) e. V. 2 Institute of Landscape Matter Dynamics 3 Institute of Soil Landscape Research Eberswalder Str. 84, D-15374 Muencheberg, Germany 4University of Potsdam, Institute of Geoecology, Karl-Liebknecht-Str. 24-25, 14476 Potsdam, Germany Microbial respiration activities correlated to sequentially separated, particulate and water-soluble organic matter fractions from arable and forest topsoils Microbial decomposition of soil organic matter (SOM) accounts for roughly half of CO2 evolution from vegetated soil surfaces and plays a crucial role in the ability of soil to mitigate the greenhouse effect. The separation and identification of labile (i.e., easily decomposable) organic matter (OM) fractions from bulk SOM is of particular importance for a mechanistic understanding of microbial decomposition processes and for predicting the response of SOM to changes in land use, management, and climate. This work aimed to reveal differences in the relevance of particulate as well as water-soluble organic matter (OM) fractions from topsoils to the easily biodegradable soil organic matter (SOM). We selected eight paired sites with quite different soil types (Udorthent, Paleudalf, Glossudalf, Aquept, Hapludalf, Aquert, Udert, Haplorthod) and soil properties (e.g., clay content: 28 to 564 g kg-1). For each of these sites, we took samples from adjacent arable and forest topsoils. Physically uncomplexed, macro-, and micro-aggregate-occluded organic particle, as well as water-soluble OM fractions were sequentially separated by a combination of electrostatic attraction, ultrasonic treatment, density separation, sieving, and water extraction. The easily biodegradable SOM of the topsoil samples was determined by measuring microbial respiration during a short-term incubation

  20. Isotope fractionation between dissolved and suspended particulate Fe in the oxic and anoxic water column of the Baltic Sea

    M. Staubwasser


    Full Text Available Fe isotope ratios and concentrations of dissolved Fe (Fedis, < 0.45 μm and of suspended particulate Fe (FeSPM were analyzed from a depth profile through the anoxic Eastern Gotland Basin water column, Baltic Sea. Results show a sharp gradient in δ56Fedis across the ferruginous layer with δ56Fedis = −0.4‰ in the euxinic deep basin and δ56Fedis = +0.3‰ in the oxic upper water column. The isotopic gradient overlaps with a strong concentration gradient of Fedis, a concentration maximum in FeSPM and lower δ56FeSPM values than δ56Fedis. These features indicate preferential loss of light Fe isotopes from solution to suspended iron-oxyhydroxides (FeIOH during typical oxidative precipitation across the redox interface. The sign of the overall fractionation, Δ56FeIOH-Fe(II(aq < 0‰, is in contrast to similar, mostly non-marine redox environments, where Δ56FeIOH-Fe(II(aq > 0‰. The difference appears to be the result of isotope exchange dominated by reaction kinetics in the marine water column, rather than equilibrium fractionation generally inferred for oxidative Fe precipitation elsewhere. High residual δ56Fedis immediately above the oxic–ferruginous interface and throughout the oxic water column suggests that any potential dissolved Fe export from marine reducing waters into the oxic open water column is enriched in the heavy isotopes. In the deep, mildly euxinic water column above the level of Fe sulfide saturation, a decreasing δ56FeSPM trend with depth and a generally low δ56Fedis are comparable to trends generally observed in marine anoxic sediment profiles where microbial reductive Fe dissolution occurs. The isotope composition of the redox-cycled Fe

  1. Barium in Twilight Zone suspended matter as a potential proxy for particulate organic carbon remineralization: Results for the North Pacific

    Dehairs, F.; Jacquet, S.; Savoye, N.; Van Mooy, B.A.S.; Buesseler, K.; Bishop, J.K.B.; Lamborg, C.H.; Elskens, M.; Baeyens, W.; Boyd, P.W.; Casciotti, K.L.; Monnin, C.


    This study focuses on the fate of exported organic carbon in the twilight zone at two contrasting environments in the North Pacific: the oligotrophic ALOHA site (22 degrees 45 minutes N 158 degrees W; Hawaii; studied during June-July 2004) and the mesotrophic Subarctic Pacific K2 site (47 degrees N, 161 degrees W; studied during July-August 2005). Earlier work has shown that non-lithogenic, excess particulate Ba (Ba{sub xs}) in the mesopelagic water column is a potential proxy of organic carbon remineralization. In general Ba{sub xs} contents were significantly larger at K2 than at ALOHA. At ALOHA the Ba{sub xs} profiles from repeated sampling (5 casts) showed remarkable consistency over a period of three weeks, suggesting that the system was close to being at steady state. In contrast, more variability was observed at K2 (6 casts sampled) reflecting the more dynamic physical and biological conditions prevailing in this environment. While for both sites Ba{sub xs} concentrations increased with depth, at K2 a clear maximum was present between the base of the mixed layer at around 50m and 500m, reflecting production and release of Ba{sub xs}. Larger mesopelagic Ba{sub xs} contents and larger bacterial production in the twilight zone at the K2 site indicate that more material was exported from the upper mixed layer for bacterial degradation deeper, compared to the ALOHA site. Furthermore, application of a published transfer function (Dehairs et al., 1997) relating oxygen consumption to the observed Ba{sub xs} data indicated that the latter were in good agreement with bacterial respiration, calculated from bacterial production. These results corroborate earlier findings highlighting the potential of Ba{sub xs} as a proxy for organic carbon remineralization. The range of POC remineralization rates calculated from twilight zone excess particulate Ba contents did also compare well with the depth dependent POC flux decrease as recorded by neutrally buoyant sediment traps

  2. Atmospheric Dust in the Upper Colorado River Basin: Integrated Analysis of Digital Imagery, Total Suspended Particulate, and Meteorological Data

    Urban, F. E.; Reynolds, R. L.; Neff, J. C.; Fernandez, D. P.; Reheis, M. C.; Goldstein, H.; Grote, E.; Landry, C.


    Improved measurement and observation of dust emission and deposition in the American west would advance understanding of (1) landscape conditions that promote or suppress dust emission, (2) dynamics of dryland and montane ecosystems, (3) premature melting of snow cover that provides critical water supplies, and (4) possible effects of dust on human health. Such understanding can be applied to issues of land management, water-resource management, as well as the safety and well-being of urban and rural inhabitants. We have recently expanded the scope of particulate measurement in the Upper Colorado River basin through the establishment of total-suspended-particulate (TSP) measurement stations located in Utah and Colorado with bi-weekly data (filter) collection, along with protocols for characterizing dust-on-snow (DOS) layers in Colorado mountains. A sub-network of high-resolution digital cameras has been co-located with several of the TSP stations, as well as at other strategic locations. These real-time regional dust-event detection cameras are internet-based and collect digital imagery every 6-15 minutes. Measurements of meteorological conditions to support these collections and observations are provided partly by CLIM-MET stations, four of which were deployed in 1998 in the Canyonlands (Utah) region. These stations provide continuous, near real-time records of the complex interaction of wind, precipitation, vegetation, as well as dust emission and deposition, in different land-use settings. The complementary datasets of dust measurement and observation enable tracking of individual regional dust events. As an example, the first DOS event of water year 2012 (Nov 5, 2011), as documented at Senator Beck Basin, near Silverton, Colorado, was also recorded by the camera at Island-in-the-Sky (200 km to the northwest), as well as in aeolian activity and wind data from the Dugout Ranch CLIM-MET station (170 km to the west-northwest). At these sites, strong winds and the

  3. Short-term Influences on Suspended Particulate Matter Distribution in the Northern Gulf of Mexico: Satellite and Model Observations

    Dong S. Ko


    Full Text Available Energetic meteorological events such as frontal passages and hurricanes often impact coastal regions in the northern Gulf of Mexico that influence geochemical processes in the region. Satellite remote sensing data such as winds from QuikSCAT, suspended particulate matter (SPM concentrations derived from SeaWiFS and the outputs (sea level and surface ocean currents of a nested navy coastal ocean model (NCOM were combined to assess the effects of frontal passages between 23-28 March 2005 on the physical properties and the SPM characteristics in the northern Gulf of Mexico. Typical changes in wind speed and direction associated with frontal passages were observed in the latest 12.5 km wind product from QuikSCAT with easterly winds before the frontal passage undergoing systematic shifts in direction and speed and turning northerly, northwesterly during a weak and a strong front on 23 and 27 March, respectively. A quantitative comparison of model sea level results with tide gauge observations suggest better correlations near the delta than in the western part of the Gulf with elevated sea levels along the coast before the frontal passage and a large drop in sea level following the frontal passage on 27 March. Model results of surface currents suggested strong response to wind forcing with westward and onshore currents before the frontal passage reversing into eastward, southeastward direction over a six day period from 23 to 28 March 2005. Surface SPM distribution derived from SeaWiFS ocean color data for two clear days on 23 and 28 March 2005 indicated SPM plumes to be oriented with the current field with increasing concentrations in nearshore waters due to resuspension and discharge from the rivers and bays and its seaward transport following the frontal passage. The backscattering spectral slope γ, a parameter sensitive to particle size distribution also indicated lower γ values (larger particles in nearshore waters that decreased

  4. Light Scattering Properties of Suspended Particulate Matter in Yellow Sea and Bohai Sea%黄渤海悬浮颗粒物散射特性研究

    沈晓晶; 丘仲锋; 孙德勇; 何宜军; 王胜强


    【目的】研究悬浮颗粒物的散射特性,用以描述水体固有光学特性。【方法】利用2014年11月黄渤海海区航测数据,分别选取555 nm 和532 nm 作为参考波长,建立悬浮颗粒物散射及后向散射的光谱模型,并对模型拟合效果进行检验;此外,还建立了悬浮颗粒物散射参数与水体组分浓度的关系模型。【结果】模型验证结果表明:光谱模型的平均相对误差绝对值(MAPE)分别在60%和35%以内;散射参数与悬浮颗粒物质量浓度模型MAPE 的最小值仅为15.0%。【结论】黄渤海颗粒物散射特性主要由非藻类颗粒物主导。%Objective]The scattering properties of suspended particulates were analyzed to de﹣scribe important inherent optical properties of water.[Methods]In this study,light scattering properties of suspended particulate matter in Yellow Sea and Bohai Sea were investigated in November 2014.Based on these data,spectrum models of the scattering and backscattering co﹣efficient of suspended particulate matter were developed using 555 nm and 532 nm as the refer﹣ence bands.In addition,estimation models of scattering parameters were developed using con﹣centrations of water constitutes.[Results]The model performance assessments indicated that the mean absolute percentage errors (MAPE)of spectrum models were within 60% and 35%. Among the estimation models of scattering properties using concentrations of water consti﹣tutes,those models using concentrations of suspended particulate matter are the best,with the minimum MAPE of 15%.[Conclusion]These results imply that non-algal particles may be the dominant component controlling the scattering properties of suspended particulate matter in this region.

  5. Quantifying uncertainty in the measurement of arsenic in suspended particulate matter by Atomic Absorption Spectrometry with hydride generator

    Ahuja Tarushee


    Full Text Available Abstract Arsenic is the toxic element, which creates several problems in human being specially when inhaled through air. So the accurate and precise measurement of arsenic in suspended particulate matter (SPM is of prime importance as it gives information about the level of toxicity in the environment, and preventive measures could be taken in the effective areas. Quality assurance is equally important in the measurement of arsenic in SPM samples before making any decision. The quality and reliability of the data of such volatile elements depends upon the measurement of uncertainty of each step involved from sampling to analysis. The analytical results quantifying uncertainty gives a measure of the confidence level of the concerned laboratory. So the main objective of this study was to determine arsenic content in SPM samples with uncertainty budget and to find out various potential sources of uncertainty, which affects the results. Keeping these facts, we have selected seven diverse sites of Delhi (National Capital of India for quantification of arsenic content in SPM samples with uncertainty budget following sampling by HVS to analysis by Atomic Absorption Spectrometer-Hydride Generator (AAS-HG. In the measurement of arsenic in SPM samples so many steps are involved from sampling to final result and we have considered various potential sources of uncertainties. The calculation of uncertainty is based on ISO/IEC17025: 2005 document and EURACHEM guideline. It has been found that the final results mostly depend on the uncertainty in measurement mainly due to repeatability, final volume prepared for analysis, weighing balance and sampling by HVS. After the analysis of data of seven diverse sites of Delhi, it has been concluded that during the period from 31st Jan. 2008 to 7th Feb. 2008 the arsenic concentration varies from 1.44 ± 0.25 to 5.58 ± 0.55 ng/m3 with 95% confidence level (k = 2.

  6. Evaluation of airborne respirable particulate matter and polycyclic aromatic hydrocarbon exposure of asphalt workers

    Teresa Cirillo


    Full Text Available

    Introduction: Assessment of exposure to the airborne respirable particles (PM10 and polycyclic aromatic hydrocarbons (PAHs of asphalt manufacturing and road paving workers in the Campania region (Italy.

    Materials and Methods: A study was carried out during 2006 and involved 5 firms producing and employing bitumen in road paving activities. The workers studied were categorized on the basis of their job as workers in bitumen manufacturing, in road paving and in workers not exposed at bitumen fume considered like controls.

    Results: In the manufacturing plants the average concentrations of airborne PM10 were 1125±445 ìg/m3 in the HMA manufacturing workers’ areas; 314±81 ìg/m3 in the process surveyors’ cabins and 92±27 ìg/m3 in the controls’ areas (administrative offices. Within the breathing zones of the worker, the average PAHs levels in air were as follows: 367±198 ng/m3 for HMA manufacturing workers; 348±172 ng/m3 for process surveyors; 21±2 ng/m3 for the controls. At the road paving sites the average airborne PM10 levels were 1435±325 ìg/m3 for roller operators; 1610±356 ìg/m3 for paver operators; 319±108 ìg/m for the controls (traffic controllers. PAHs in the breathing zones were 1220±694 ng/m3 for the paver operators; 1360±575 ng/m3 for the roller operators’ and 139±135 ng/m3 for the traffic controllers’. The results show that the more consistent hazard for asphalt workers’ health is derived from exposure to airborne PM10 both in exposed and in non-exposed (controls workers.

  7. Transport and distribution of trace elements and other selected inorganic constituents by suspended particulates in the Salton Sea Basin, California, 2001

    LeBlanc, L.A.; Schroeder, R.A.


    In order to examine the transport of contaminants associated with river-derived suspended particles in the Salton Sea, California, large volume water samples were collected in transects established along the three major rivers emptying into the Salton Sea in fall 2001. Rivers in this area carry significant aqueous and particulate contaminant loads derived from irrigation water associated with the extensive agricultural activity, as well as wastewater from small and large municipalities. A variety of inorganic constituents, including trace metals, nutrients, and organic carbon were analyzed on suspended material isolated from water samples collected at upriver, near-shore, and off-shore sites established on the Alamo, New, and Whitewater rivers. Concentration patterns showed expected trends, with river-borne metals becoming diluted by organic-rich algal particles of lacustrine origin in off-shore stations. More soluble metals, such as cadmium, copper, and zinc showed a more even distribution between sites in the rivers and off-shore in the lake basin. General distributional trends of trace elements between particulate and aqueous forms were discerned by combining metal concentration data for particulates from this study with historical aqueous metals data. Highly insoluble trace metals, such as iron and aluminum, occurred almost entirely in the particulate phase, while major cations and approximately 95% of selenium were transported in the soluble phase. Evidence for greater reducing conditions in the New compared to the Alamo River was provided by the greater proportion of reduced (soluble) manganese in the New River. Evidence of bioconcentration of selenium and arsenic within the lake by algae was provided by calculating "enrichment" concentration ratios from metal concentrations on the algal-derived particulate samples and the off-shore sites. ?? 2008 Springer Science+Business Media B.V.

  8. Defining an exposure-response relationship for suspended kaolin clay particulates and aquatic organisms: work toward defining a water quality guideline for suspended solids.

    Gordon, Andrew K; Palmer, Carolyn G


    Water quality guidelines for suspended solids generally rely on the percentage departure from reference condition, an approach that has been criticized. Attempts to develop a biological effects-base guideline have, however, been confounded by low data availability. Furthermore, the high biological response variability to suspended solids exposure suggests that organisms are responding not only to exposure concentration and duration but also to other mechanisms of effect associated with suspended particles (e.g., size, shape, and geochemical composition). An alternative option is to develop more situation and site specific guidelines by generating biological effects data to suspended particles of a particular geochemistry and restricted size range. With this in mind, aquatic organism responses to kaolin clay particle exposure were collated from the literature and incorporated into 2 exposure-response relationship approaches. The species sensitivity distribution approach produced a hazardous concentration affecting 5% of species estimate of 58 mg/L for mortality responses, and 36 mg/L for sublethal data. The severity-of-ill-effect approach produced similar estimates for lethal and sublethal data. These results suggest that aquatic organisms are slightly more tolerant of kaolin clay particles than particles from barite or bentonite clays, based on results from previous studies on these clay types. This type of information can enable better estimates of the risk faced by aquatic organisms exposed to suspended solids. For example, when the sediments of a particular water body are dominated by a particular type of clay particle, then the most appropriate exposure-response relationship can be applied. © 2015 SETAC.

  9. Fine (PM2.5), coarse (PM2.5-10), and metallic elements of suspended particulates for incense burning at Tzu Yun Yen temple in central Taiwan.

    Fang, Guor-Cheng; Chang, Cheng-Nan; Chu, Chia-Chium; Wu, Yuh-Shen; Pi-Cheng Fu, Peter; Chang, Shyh-Chyi; Yang, I-Lin


    Ambient suspended particulate concentrations were measured at Tzu Yun Yen temple (120 degrees, 34('), 10(") E; 24 degrees, 16('), 12(") N) in this study. This is representative of incense burning and semi-open sampling sites. The Universal-sampler collected fine and coarse particle material was used to measure suspended particulate concentrations, and sampling periods were from 16/08/2001 to 2/1/2002 at Tzu Yun Yen temple. In addition, metallic element concentrations, compositions of PM(2.5) and PM(2.5-10) for incense burning at Tzu Yun Yen temple were also analyzed in this study. The PM(2.5)/PM(10) ratios ranged between 31% and 87% and averaged 70+/-11% during incense the burning period, respectively. The median metallic element concentration order for these elements is Fe>Zn>Cr>Cd>Pb>Mn>Ni>Cu in fine particles (PM(2.5)) at the Tzu Yun Yen temple sampling site. The median metallic element concentration order for these elements is Fe>Zn>Cr>Pb>Cd>Ni>Mn>Cu in coarse particle (PM(2.5-10)) at the Tzu Yun Yen temple sampling site. Fine particulates (PM(2.5)) are the main portion of PM(10) at Tzu Yun Yen temple in this study. From the point of view of PM(10), these data reflect that the elements Fe, Zn, and Cr were the major elements distributed at Tzu Yun Yen temple in this study.

  10. Annual cycle and spatial trends in fatty acid composition of suspended particulate organic matter across the Beaufort Sea shelf

    Connelly, Tara L.; Businski, Tara N.; Deibel, Don; Parrish, Christopher C.; Trela, Piotr


    Fatty acid profiles of suspended particulate organic matter (POM) were determined over an annual cycle (September 2003 to August 2004) on the Beaufort Sea shelf, Canadian Arctic. Special emphasis was placed on the nutritional quality of the fatty acid pool available to zooplankton by examining spatial and temporal patterns in the proportions of total polyunsaturated fatty acids (PUFA) and the essential fatty acids 22:6n-3 (DHA) and 20:5n-3 (EPA). EPA and DHA were the two most abundant PUFA throughout the study period. A log-ratio multivariate (LRA) analysis revealed strong structure in fatty acid profiles related to season and depth. Dominant fatty acids accounting for the observed trend included 18:5n-3, 18:4n-3, 16:1n-7, 20:5n-3, 18:0 and 20:3n-3. We observed a shift in fatty acid profiles from summer to autumn (e.g., from 16:1n-7 and EPA to 18:5n-3 and 18:4n-3) that likely corresponded to a shift in the relative importance of diatoms versus dinoflagellates, prymnesiophytes and/or prasinophytes to the POM pool. Fatty acid composition during winter was dominated by more refractory saturated fatty acids. A surprising finding was the depth and seasonal trend of 20:3n-3, which was higher in winter, aligned with 18:0 in the LRA, but behaved differently than other n-3 PUFA. We interpret fatty acid profiles during summer to be predominantly driven by phytoplankton inputs, whereas fatty acid profiles in winter were dominated by fatty acids that were left over after consumption and/or were generated by heterotrophs. The highest diatom inputs (EPA, the diatom fatty acid marker), n-3/n-6 ratios, and C16 PUFA index were located in an upwelling region off Cape Bathurst. This study is the first annual time series of fatty acid profiles of POM in Arctic seas, expanding our knowledge of the composition of POM throughout the dark season.

  11. Decreasing trends of suspended particulate matter and PM2.5 concentrations in Tokyo, 1990-2010.

    Hara, Kunio; Homma, Junichi; Tamura, Kenji; Inoue, Mariko; Karita, Kanae; Yano, Eiji


    In Tokyo, the annual average suspended particulate matter (SPM) and PM2.5 concentrations have decreased in the past two decades. The present study quantitatively evaluated these decreasing trends using data from air-pollution monitoring stations. Annual SPM and PM2.5 levels at 83 monitoring stations and hourly SPM and PM2.5 levels at four monitoring stations in Tokyo, operated by the Tokyo Metropolitan Government, were used for analysis, together with levels of co-pollutants and meteorological conditions. Traffic volume in Tokyo was calculated from the total traveling distance of vehicles as reported by the Ministry of Land, Infrastructure, Transport, and Tourism. High positive correlations between SPM levels and nitrogen oxide levels, sulfur dioxide levels, and traffic volume were determined. The annual average SPM concentration declined by 62.6%from 59.4 microg/m3 in 1994 to 22.2 microg/m3 in 2010, and PM2.5 concentration also declined by 49.8% from 29.3 microg/m3 in 2001 to 14.7 microg/m3 in 2010. Likewise, the frequencies of hourly average SPM and PM2.5 concentrations exceeding the daily guideline values have significantly decreased since 2001 and the hourly average SPM or PM2.5 concentrations per traffic volume for each time period have also significantly decreased since 2001. However SPM and PM2.5 concentrations increased at some monitoring stations between 2004 and 2006 and from 2009 despite strengthened environmental regulations and improvements in vehicle engine performance. The annual average SPM and PM2.5 concentrations were positively correlated with traffic volumes and in particular with the volume of diesel trucks. These results suggest that the decreasing levels of SPM and PM2.5 in Tokyo may be attributable to decreased traffic volumes, along with the effects of stricter governmental regulation and improvements to vehicle engine performance, including the fitting of devices for exhaust emission reduction.

  12. Evaluation of AERMOD and CALPUFF for predicting ambient concentrations of total suspended particulate matter (TSP) emissions from a quarry in complex terrain.

    Tartakovsky, Dmitry; Broday, David M; Stern, Eli


    Concentrations of particulate emissions from a quarry located in hilly terrain were calculated by two common atmospheric dispersion models, AERMOD and CALPUFF. Evaluation of these models for emissions from quarries/open pit mines that are located in complex topography is missing from the literature. Due to severe uncertainties in the input parameters, numerous scenarios were simulated and model sensitivity was studied. Model results were compared among themselves, and to measured total suspended particulate (TSP). For a wide range of meteorological and topographical conditions studied, AERMOD predictions were in a better agreement with the measurements than those obtained by CALPUFF. The use of AERMOD's "Open pit" tool seems unnecessary when accurate digital topographic data are available. Onsite meteorological data are shown to be crucial for reliable dispersion calculations in complex terrain.

  13. Ambient concentrations of total suspended particulate matter and its elemental constituents at the wider area of the mining facilities of TVX Hellas in Chalkidiki, Greece.

    Gaidajis, George


    To assess ambient air quality at the wider area of TVX Hellas mining facilities, the Total Suspended Particulate matter (TSP) and its content in characteristic elements, i.e., As, Cd, Cu, Fe, Mn, Pb, Zn are being monitored for more than thirty months as part of the established Environmental Monitoring Program. High Volume air samplers equipped with Tissue Quartz filters were employed for the collection of TSP. Analyses were effected after digestion of the suspended particulate with an HNO3-HCl solution and determination of elemental concentrations with an Atomic Absorption Spectroscopy equipped with graphite furnace. The sampling stations were selected to record representatively the existing ambient air quality in the vicinity of the facilities and at remote sites not affected from industrial activities. Monitoring data indicated that the background TSP concentrations ranged from 5-60 microg/m3. Recorded TSP concentrations at the residential sites close to the facilities ranged between 20-100 microg/m3, indicating only a minimal influence from the mining and milling activities. Similar spatial variation was observed for the TSP constituents and specifically for Pb and Zn. To validate the monitoring procedures, a parallel sampling campaign took place with different High Volume samplers at days where low TSP concentrations were expected. The satisfactory agreement (+/- 11%) at low concentrations (50-100 microg/m3) clearly supported the reproducibility of the techniques employed specifically at the critical range of lower concentrations.

  14. Seamounts and organic matter—Is there an effect? The case of Sedlo and Seine seamounts, Part 2. Composition of suspended particulate organic matter

    Kiriakoulakis, K.; Vilas, J. C.; Blackbird, S. J.; Arístegui, J.; Wolff, G. A.


    The suspended particulate organic matter (sPOM) around two isolated NE Atlantic seamounts, Seine (33°46'N 14°21'W; summit at ˜170 m) and Sedlo (40°19'N 26°40'W; summit at ˜780 m), was studied over a period of 2 years during four 2-4-week oceanographic surveys. Elemental (C and N), chlorophyll a and lipid biomarker concentrations and N stable isotopic values were variable close to the surface (40-90 m), although some chlorophyll a enrichment above the summits was discerned sporadically. Results from near-surface waters showed a generally "fresh", mainly phytoplankton signature in sPOM with some seasonality, which was more pronounced around Sedlo. sPOM concentrations and composition changed with depth, apparently controlled by seasonality and proximity to the seamounts. A few metres above the Seine summit, the suspended particulate organic carbon (sPOC) concentrations and labile polyunsaturated fatty acids (% of lipids) were higher than elsewhere at similar depths (˜200 m) in summer 2004. In the same season at Sedlo, polyunsaturated fatty acids were also relatively more abundant (up to 43% of total lipids) around the topographic feature throughout the water column, indicating supply of more labile sPOM, perhaps by advection, downwelling or passive sinking of locally produced phytoplankton and/or in situ production. The high-quality sPOM that seems to be present around the seamounts could provide an important food source to the biological community.

  15. Optimization and development of analytical methods for the determination of new brominated flame retardants and polybrominated diphenyl ethers in sediments and suspended particulate matter

    Lopez, P. [VU University Amsterdam, Institute for Environmental Studies (IVM), Amsterdam (Netherlands); Institute for Reference Materials and Measurements, European Commission, Joint Research Centre, Retieseweg 111, 2440, Geel (Belgium); Brandsma, S.A.; Leonards, P.E.G.; Boer, J. de [VU University Amsterdam, Institute for Environmental Studies (IVM), Amsterdam (Netherlands)


    With more stringent legislation on brominated flame retardants, it is expected that increasing amounts of substitutes would replace polybrominated diphenylethers (PBDEs). Therefore, the development and optimization of analytical methodologies that allow their identification and quantification are of paramount relevance. This work describes the optimization of an analytical procedure to determine pentabromochlorocyclohexane, tetrabromo-o-chlorotoluene, 2,3,5,6-tetrabromo-p-xylene, tetrabromophthalic anhydride, 2,3,4,5,6-pentabromotoluene, tris(2,3-dibromopropyl)phosphate, decabromodiphenylethane and 1,2-bis(2,4,6-tribromophenoxy)ethane together with PBDEs in sediments and in suspended particulate matter. This method comprises a pressurized liquid extraction followed by three cleanup steps (gel permeation chromatography and solid phase extraction on Oasis trademark HLB and on silica cartridges). Gas chromatography-mass spectrometry, using electron capture negative chemical ionization, is used for the final analysis. The proposed method provides recoveries >85%. The method was applied to sediment and suspended particulate matter samples from different locations in the Western Scheldt estuary (the Netherlands). To the best of our knowledge, this is the first time that the occurrence of the additive flame retardants 2,3,5,6-tetrabromo-p-xylene, 3,4,5,6-tetrabromo-o-chlorotoluene and 2,3,4,5,6-pentabromochlorocyclohexane is reported in the literature. The concentrations of these new flame retardants ranged from 0.05 to 0.30 {mu}g/kg dry weight. (orig.)

  16. Consistent assessment of trace metal contamination in surface sediments and suspended particulate matter: a case study from the Jade Bay in NW Germany.

    Beck, Melanie; Böning, Philipp; Schückel, Ulrike; Stiehl, Thorsten; Schnetger, Bernhard; Rullkötter, Jürgen; Brumsack, Hans-Jürgen


    Recently, within the framework of European directives, the importance of marine monitoring programs has increased. In this study, a dense sampling grid was applied for a detailed assessment of the metal contents of surface sediments and suspended particulate matter from the Jade Bay, one of the tidal basins in the southern North Sea. The local lithogenic background was defined and compared with average shale, a common reference material. Based on the calculated non-lithogenic fraction and a cluster analysis, the metals are distributed in two groups: (i) elements of mainly natural origin (Co, Cr, and a major portion of Cd) and (ii) elements associated with anthropogenic activity (As, Cd, Cu, Ni, Pb, Sn, and Zn). However, even the metals of the second group are enriched by at most a factor of two relative to the local background, suggesting minimal anthropogenic impact. Spatial distribution maps show that the harbor area of Wilhelmshaven may be a particularly important source of metal.

  17. Performance of an N95 filtering facepiece particulate respirator and a surgical mask during human breathing: two pathways for particle penetration.

    Grinshpun, Sergey A; Haruta, Hiroki; Eninger, Robert M; Reponen, Tiina; McKay, Roy T; Lee, Shu-An


    The protection level offered by filtering facepiece particulate respirators and face masks is defined by the percentage of ambient particles penetrating inside the protection device. There are two penetration pathways: (1) through the faceseal leakage, and the (2) filter medium. This study aimed at differentiating the contributions of these two pathways for particles in the size range of 0.03-1 microm under actual breathing conditions. One N95 filtering facepiece respirator and one surgical mask commonly used in health care environments were tested on 25 subjects (matching the latest National Institute for Occupational Safety and Health fit testing panel) as the subjects performed conventional fit test exercises. The respirator and the mask were also tested with breathing manikins that precisely mimicked the prerecorded breathing patterns of the tested subjects. The penetration data obtained in the human subject- and manikin-based tests were compared for different particle sizes and breathing patterns. Overall, 5250 particle size- and exercise-specific penetration values were determined. For each value, the faceseal leakage-to-filter ratio was calculated to quantify the relative contributions of the two penetration pathways. The number of particles penetrating through the faceseal leakage of the tested respirator/mask far exceeded the number of those penetrating through the filter medium. For the N95 respirator, the excess was (on average) by an order of magnitude and significantly increased with an increase in particle size (p < 0.001): approximately 7-fold greater for 0.04 microm, approximately 10-fold for 0.1 microm, and approximately 20-fold for 1 microm. For the surgical mask, the faceseal leakage-to-filter ratio ranged from 4.8 to 5.8 and was not significantly affected by the particle size for the tested submicrometer fraction. Facial/body movement had a pronounced effect on the relative contribution of the two penetration pathways. Breathing intensity and

  18. Results from an intensive measurement programme for suspended particulate matter in a region of the Irish Sea between Anglesey and the Isle of Man

    Smith, Christopher N.; Stewart, T. Henry; McDonald, Paul


    Suspended particulate matter (SPM) plays an important role in the transport of metals and other contaminants in the marine environment. To varying degrees dissolved metals are scavenged by suspended particles and this can have a significant impact on the transport and dispersion of the metal. In contaminated areas, such as the Irish Sea, the SPM becomes increasingly important in understanding the transport and fate of contaminants. Despite its importance, measurements of SPM in the Irish Sea are sparse. This paper presents measured SPM concentrations from a long-term sampling campaign from 25 sites in an area of the Irish Sea between Anglesey and the Isle of Man which were sampled over 14 months (July 1998-August 1999) at 5 and 30 m depth. In total 585 measurements were made. A transmissometer was also deployed on some occasions to look at the depth dependence of SPM. Results showed an average SPM concentration of 2.14 mg l -1 with a maximum value of 6.28 mg l -1 and a minimum of 0.30 mg l -1. The strongest relationship found was between the SPM and the spring-neap tidal cycle, which outweighed any seasonal variation. Spatially, the SPM was highest in the south and east of the region sampled and is probably due to higher tidal velocities and greater availability of fine sediment in these areas. There was no evidence of SPM varying with depth in the water column.

  19. A critical examination of the possible application of zinc stable isotope ratios in bivalve mollusks and suspended particulate matter to trace zinc pollution in a tropical estuary.

    Araújo, Daniel; Machado, Wilson; Weiss, Dominik; Mulholland, Daniel S; Boaventura, Geraldo R; Viers, Jerome; Garnier, Jeremie; Dantas, Elton L; Babinski, Marly


    The application of zinc (Zn) isotopes in bivalve tissues to identify zinc sources in estuaries was critically assessed. We determined the zinc isotope composition of mollusks (Crassostrea brasiliana and Perna perna) and suspended particulate matter (SPM) in a tropical estuary (Sepetiba Bay, Brazil) historically impacted by metallurgical activities. The zinc isotope systematics of the SPM was in line with mixing of zinc derived from fluvial material and from metallurgical activities. In contrast, source mixing alone cannot account for the isotope ratios observed in the bivalves, which are significantly lighter in the contaminated metallurgical zone (δ(66)ZnJMC = +0.49 ± 0.06‰, 2σ, n = 3) compared to sampling locations outside (δ(66)ZnJMC = +0.83 ± 0.10‰, 2σ, n = 22). This observation suggests that additional factors such as speciation, bioavailability and bioaccumulation pathways (via solution or particulate matter) influence the zinc isotope composition of bivalves. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Modelling the light absorption properties of particulate matter forming organic particles suspended in sea water. Part 3. Practical applications

    Roman Majchrowski


    Full Text Available This paper brings to a close our cycle of articles on modelling the light absorption properties of particulate organic matter (POM in the sea. In the first two parts of this cycle (Woźniaket al. 2005a,b we discussed these properties with reference to various model chemical classes and physical types of POM. We have put these results into practice in the present third part. As a result of the appropriate theoretical speculations, logically underpinned by empirical knowledge, we selected 25 morphological variants of marine organic detritus, to which we ascribed definite chemical compositions and physical types. On this basis and using known spectra of the mass-specific coefficients of light absorption by various naturally occurring organic substances (systematised in Parts 1 and 2, we determined the absorption properties of these 25 morphological groups of particles, that is, the spectra of the imaginary part of the refractive index n'p(λ (in the 200-700 nm range of the particulate matter. They can be applied, with the aid of Mie's or some other similar theory, to calculate the bulk optical properties (absorbing and scattering of such sets of particles in the sea.

  1. Isotopic equilibration between dissolved and suspended particulate lead in the Atlantic Ocean - Evidence from Pb-210 and stable Pb isotopes

    Sherrell, Robert M.; Boyle, Edward A.; Hamelin, Bruno


    Vertical profiles of, on one hand, the stable Pb isotopic composition, and on the other, the ratio of total Pb to Pb-210 in suspended particles, are noted to closely track contemporaneous depth variations in these ratios for dissolved Pb throughout the upper 2 km of the Sargasso Sea near Bermuda. A simple flux model suggests that the effect of deep ocean scavenging processes on the flux and isotopic composition of Pb sinking on large particles was minor throughout the preanthropogenic, and most of the anthropogenic era: but it has become more important as surface inputs decrease to preleaded gasoline levels, perhaps exceeding the contribution of surface-derived Pb flux in the next decade.

  2. Multi-Mission Remote Sensing of Suspended Particulate Matter and Diffuse Attenuation Coefficient in the Yangtze Estuarine and Coastal Waters

    Yu, X.; Salama, S.; Shen, F.


    During the Dragon-3 project (ID: 10555) period, we developed and improved the atmospheric correction algorithms (AC) and retrieval models of suspended sediment concentration ( ) and diffuse attenuation coefficient ( ) for the Yangtze estuarine and coastal waters. The developed models were validated by measurements with consistently stable and fairly accurate estimations, reproducing reasonable distribution maps of and over the study area. Spatial-temporal variations of were presented and the mechanisms of the sediment transport were discussed. We further examined the compatibility of the developed AC algorithms and retrieval model and the consistency of satellite products for multi-sensor such as MODIS/Terra/Aqua, MERIS/Envisat, MERSI/ FY-3 and GOCI. The inter-comparison of multi- sensor suggested that different satellite products can be combined to increase revisit frequency and complement a temporal gap of time series satellites that may exist between on-orbit and off- orbit, facilitating a better monitor on the spatial- temporal dynamics of .

  3. Modelling the light absorption properties of particulate matter forming organic particles suspended in seawater. Part 2. Modelling results

    Bogdan Woźniak


    Full Text Available Model spectra of mass-specific absorption coefficients a*OM(λ were established for 26 naturally occurring organic substances or their possible mixtures, capable of forming particulate organic matter (POM in the sea. An algorithm was constructed, and the set of spectra of a*OM(λ was used to determine the spectra of the imaginary part of the complex refractive index n'p(λ characteristic of different physical types and chemical classes of POM commonly occurring in sea water. The variability in the spectra and absolute values of n'p for the various model classes and types of POM was shown to range over many orders of magnitude. This implies that modelling the optical properties of sea water requires a multi-component approach that takes account of the numerous living and non-living fractions of POM, each of which has a different value of n'p.

  4. Mutagenicity of organic pollutants adsorbed on suspended particulate matter in the center of Wrocław (Poland)

    Bełcik, Maciej; Trusz-Zdybek, Agnieszka; Galas, Ewa; Piekarska, Katarzyna


    Mutagenicity of pollutants adsorbed on suspended dust of the PM10 fraction, collected in winter and summer season alike over the Wrocław city centre (Poland) was studied using the standard Salmonella assay (plate-incorporation) and the Kado modified assay (microsuspension method). The dust was collected using Staplex high volume air sampler. Further on it was extracted with dichloromethane in a Soxhlet apparatus. PAH content in extracts was determined by the high performance liquid chromatography technique using fluorescence detection, whereas the nitro-PAH content- by the gas chromatography using mass detection. Two Salmonella typhimurium strains, TA98 and YG1041, were used in the assays. The assays were conducted with and without a metabolic activation. Investigated air pollution extracts differed against each other with regard to a total content as well as to a percentage of individual compounds, depending on the sampling season. Both the total PAH content and the nitro-PAH content in the tested samples, and their spectrum as well, were found the highest in winter season. Higher mutagenic effect was noted for the dust extract from samples collected in wintertime than from those collected in summer. Pollutants directly affecting the genetic material and those showing such indirect action were present in the examined samples. The YG1041 strain turned out to be the most sensitive, which was the sign that large amounts of nitro-aromatic compounds were present in the tested samples. Obtained results proved that the Kado modified Salmonella assay would be useful for the atmospheric air pollution monitoring in urban agglomerations. Mutagenic effect in assays conducted according to the Kado procedure was obtained by using in the assays lower concentrations of tested extracts, compared to the classical assay.

  5. The influence of air-suspended particulate concentration on the incidence of suicide attempts and exacerbation of schizophrenia

    Yackerson, Naomy S.; Zilberman, Arkadi; Todder, Doron; Kaplan, Zeev


    The main objective of this study was to evaluate the role of the concentration of solid air-suspended particles (SSP) in the incidence of mental disorders. The study is based on 1,871 cases, registered in the Beer-Sheva Mental Health Center (BS-MHC) at Ben-Gurion University (Israel) during a 16-month period from 2001 to 2002; 1,445 persons were hospitalized due to exacerbation of schizophrenia (ICD-10: F20-F29) and 426 after committing a suicide attempt using a variety of means as coded in the ICD-10 (ICD-10: X60-X84). Pearson and Spearman test correlations were used; the statistical significance was tested at p 0.3, p 0.2). A trend towards positive correlation ( ρ > 0.2, p 0.1). Obviously, concentration of SSP is not the one and only parameter of air pollution state determining meteorological-biological impact, involving incidence of mental disorders, although its role can scarcely be overstated. However, since it is one of the simplest measured parameters, it could be widely used and helpful in the daily struggle for human life comfort in semi-arid areas as well as urban and industrial surroundings, where air pollution reaches crucial values. This study may permit determination of the limits for different external factors, which do not overcome threshold values (without provoking avalanche situations), to single out the group of people at increased risk (with according degree of statistic probability), whose reactions to the weather violations can involve the outbreak of frustration points and prevent or alleviate detrimental mental effects.

  6. A critical and comparative appraisal of polycyclic aromatic hydrocarbons in sediments and suspended particulate material from a large South American subtropical estuary.

    Cardoso, Fernanda D; Dauner, Ana Lúcia L; Martins, César C


    The Paranaguá Estuarine Complex (PEC) is an important socioeconomic estuary of the Brazilian coast that is influenced by the input of pollutants like polycyclic aromatic hydrocarbons (PAHs). Because of the apparent lack of comparative studies involving PAHs in different estuarine compartments, the aim of this study was to determine and compare PAH concentrations in surface sediment and suspended particulate material (SPM) in the PEC to evaluate their behaviour, compositions, sources and spatial distributions. The total PAH concentrations in the sediment ranged from 0.6 to 63.8 ng g(-1) (dry weight), whereas in the SPM these concentrations ranged from 391 to 4164 ng g(-1). Diagnostic ratios suggest distinct sources of PAHs to sediments (i.e., pyrolytic sources) and SPM (i.e., petrogenic sources such as vessel traffic). Thus, the recent introduction of PAHs is more clearly indicated in the SPM since oil related-compounds (e.g., alkyl-PAHs) remain present in similar concentrations. Further, this matrix may better reflect the current state of the environment at the time of sampling because of the absence of significant degradation.

  7. Occurrence, distribution and risk assessment of suspected endocrine-disrupting chemicals in surface water and suspended particulate matter of Yangtze River (Nanjing section).

    Liu, Yan-Hua; Zhang, Sheng-Hu; Ji, Gui-Xiang; Wu, Sheng-Min; Guo, Rui-Xin; Cheng, Jie; Yan, Zheng-Yu; Chen, Jian-Qiu


    The occurrence and distribution of eight selected endocrine-disrupting chemicals were investigated in samples of surface water and suspended particulate matter (SPM) in Nanjing section of Yangtze River over a year (the flow period, the wet period and the dry period). All target compounds were detected at least once in surface water with 4-tert-butylphenol (4-TBP), nonyphenol (NP) and bisphenol A (BPA) as the dominant compounds, with concentrations in the range of 225-1121ng/L, 1.4-858ng/L and 1.7-563ng/L, respectively. Except for December, all selected compounds for the other sampling times were not found in all sampling points. NP (mean concentration 69.8µg/g) and BPA (mean concentration 51.8µg/g) were also the dominant estrogens in SPM. In addition, the highest total compounds concentrations were found in December in both phases, which could be due to the low flow conditions and temperature during this season. Meanwhile, a significant positive correlation was found between the total compounds concentrations in the water phase and those in SPM phase. Risk assessment based on the calculated risk quotients (RQ) showed that low and moderate risk for the aquatic environment from presence of the target compounds at all sampling points with exception of 4-TBP and NP which might pose a high risk to aquatic organisms.

  8. Characterization of elemental pollution and its variations in sediments and suspended particulate matter from the River Elbe via multi-element analysis combined with chemometric data evaluation.

    Aulinger, A; Prange, A; Niedergesäss, R; Schmolke, S; Einax, J W


    Sediments and suspended particulate matter taken from about 100 sampling sites along the River Elbe from the source to the mouth during the period 1992 and 1998 have been analyzed for the concentrations of more than 60 elements in each sample. The analytical data were subsequently processed by means of multivariate statistics in order to characterize the charge of the River Elbe with inorganic pollutants to elucidate pollution trends. Using factor analysis 18 elements were found to be enriched by human activities. By means of cluster analysis--using the 18 anthropogenically influenced elements as variables--the sampling sites were aggregated into groups having similar element distributions. Thus, the entire stretch of the River Elbe was divided into three sections of characteristic elemental pollution. Finally, the trends in anthropogenic pollution within the characteristic regions since the early nineties were assessed. It turned out that most of the anthropogenically influenced elements showed a decrease in the upper and middle parts of the river, whereas no decrease could be verified in the estuary region.

  9. Effects of riverine suspended particulate matter on the post-dredging increase in internal phosphorus loading across the sediment-water interface.

    Liu, Cheng; Shao, Shiguang; Shen, Qiushi; Fan, Chengxin; Zhang, Lei; Zhou, Qilin


    Dredging is frequently used in the river mouths of eutrophic lakes to reduce internal phosphorus (P) loading from the sediment. However, the accumulation of P-adsorbed suspended particulate matter (SPM) from the inflowing rivers negatively affects the post-dredging sediment-water interface and ultimately increases internal P loading. Here, a 360-d experiment was carried out to investigate the influence of riverine SPM on the efficacy of dredging in reducing internal P loading. SPM was added to dredged and undredged sediments collected from the confluence area of Lake Chaohu. Several parameters related to internal P loading, including oxygen profile, soluble reactive P, and ferrous iron across the sediment-water interface, organic matter, alkaline phosphatase activity, and P fractions, were measured throughout the experimental period. The results showed that the P content (especially mobile P) in the sediment increased to the pre-dredging level with the accumulation of SPM in the dredged sediment. In addition, the P flux across the sediment-water interface increased with the accumulation of SPM. Several characteristics of SPM, including high organic matter content, mobile P, high activity of alkaline phosphatase, and high biological activity, were considered correlated with the post-dredging increase in internal P loading. Overall, this study showed that the heavily contaminated riverine SPM regulates the long-term efficacy of dredging as a nutrient management option in the confluence area. Management is needed to avoid or reduce this phenomenon during dredging projects of this nature.

  10. Human health risk assessment based on trace metals in suspended air particulates, surface dust, and floor dust from e-waste recycling workshops in Hong Kong, China.

    Lau, Winifred Ka Yan; Liang, Peng; Man, Yu Bon; Chung, Shan Shan; Wong, Ming Hung


    This study investigated health risks exerted on electronic waste (e-waste) recycling workers exposed to cadmium (Cd), chromium (Cr), copper (Cu), lead (Pb), nickel (Ni), mercury (Hg), and zinc (Zn) in Hong Kong. E-waste recycling workshops were classified into eight working areas: 1 = office, 2 = repair, 3 = dismantling, 4 = storage, 5 = desoldering, 6 = loading, 7 = cable shredding, and 8 = chemical waste. The aforementioned metal concentrations were analyzed in suspended air particulates, surface dust and floor dust collected from the above study areas in five workshops. Elevated Pb levels were measured in dismantling and desoldering areas (582 and 486 μg/100 cm(2) in surface and 3,610 and 19,172 mg/kg in floor dust, respectively). Blood lead levels of 10 and 39.5 μg/dl were estimated using United States Environmental Protection Agency's Adult Lead Model as a result of exposure to the floor dust from these two areas. Human health risk assessments were conducted to evaluate cancer and noncancer risks resulting from exposure to floor dust through the combined pathways of ingestion, dermal contact, and inhalation. Findings indicated that workers may be exposed to cancer risks above the acceptable range at 147 in a million at the 95th percentile in the dismantling area. Workers should be informed of associated risks to safeguard their health.

  11. Distribution and Source of Polycyclic Aromatic Hydrocarbons (PAHs) in Water Dissolved Phase, Suspended Particulate Matter and Sediment from Weihe River in Northwest China.

    Chen, Yuyun; Jia, Rui; Yang, Shengke


    Weihe River is a typical river located in the arid and semi-arid regions of Northwest China. In this study, the distribution and sources of 16 polycyclic aromatic hydrocarbons (PAHs) in Weihe River were investigated. The concentrations of ∑PAHs ranged from 351 to 4427 ng/L with a mean value of 835.4 ng/L in water dissolved phase (WDP), from 3557 ng/L to 147,907 ng/L with a mean value of 20,780 ng /L in suspended particulate matter (SPM), and from 362 to 15,667 ng/g dry weight (dw) with a mean value of 2000 ng/g dw in sediment, respectively. The concentrations of PAHs in Weihe River were higher compared with other rivers in the world. In both WDP and sediment, the highest concentrations of ∑PAHs were observed in the middle reach, while the lowest concentrations of ∑PAHs were found in the lower reach. For SPM, however, the PAHs concentrations in the lower reach were highest and the PAHs concentrations in the upper reach were lowest. The ratios of anthracene/(anthracene + phenanthrene) and fluoranthene/ (fluoranthene + pyrene) reflected a pattern of both pyrolytic and petrogenic input of PAHs in Weihe River. The potential ecosystem risk assessment indicated that harmful biological impairments occur frequently in Weihe River.

  12. Chemical speciation of Fe, Mn, Pb, Zn, Cd, Cu, Co, Ni and Cr in the suspended particulate matter off the Mejerda River Delta (Gulf of Tunis, Tunisia)

    Helali, Mohamed Amine; Oueslati, Walid; Zaaboub, Noureddine; Added, Ayed; Aleya, Lotfi


    Fluxes of suspended particulate matter (SPM) and their associated metals were performed off the Mejerda River Delta during both the wet (March) and the dry (July) seasons in 2012, using sediment traps at study stations at depths of 10, 20 and 40 m. Fluxes nearest to the Mejerda outlet were more significant, especially during winter (36 g m-2 day-1), but dissipated further offshore, 24.5-6 g m-2 day-1 at the 20 m and 21.8-4.8 g m-2 day-1 at the 40 m stations. Many variations observed in seasonal and spatial metal fluxes are similar to those of SPM, in particular Pb and Zn, probably because they are associated with the mining activity characteristic of the Mejerda catchment. Chemical speciation reveals that most of the metals (20-100%) are bound to the residual fraction. The most toxic metals (Pb, Zn) are bound in part to the exchangeable fraction (20-50% for Pb and 5-15% for Zn) making them relatively bioavailable and therefore potentially toxic. While Cu and Cd fluxes are not always clearly established according to season, both metals are apparently sequestered deep in the sediment, bound especially to clays (40-80% for Cd and up to 100% for Cu).

  13. Physical characteristics and discharges of suspended particulate matter at the continent-ocean interface in an estuary located in a semiarid region in northeastern Brazil

    Dias, Francisco Jose da Silva; Castro, Belmiro Mendes; Lacerda, Luiz Drude; Miranda, Luiz Brunner; Marins, Rozane Valente


    This study reports the hydrodynamics of the transport of suspended particulate matter (SPM) in the Jaguaribe River estuary, which receives the runoff from the largest drainage basin in the state of Ceará, Brazil. The estuary is located in the semiarid region of Brazil, where rainfall occurs primarily between January and May and results in water flow rates exceeding 3000 m3s-1. The drainage basin contains more than 4000 dams, which, during the dry season, block most of the flow of freshwater and sediment. The net balance and transport of sediments were calculated for the wet and dry seasons considering a tidal cycle of 13 h at the interfaces between the upper and middle estuary and between the middle and lower estuary. The Jaguaribe River estuary is classified as partially mixed with weak vertical stratification and a tendency toward being well mixed. The SPM transported during the rainy season originates in the drainage basin due to high river inflow, whereas during the dry season, resuspension and hydraulic fills generated by tides causes the accumulation of SPM in the middle estuary, forming a zone of maximum turbidity. The transport of salt in the estuary was predominantly caused by gravity flow and tidal propagation.

  14. A review of oil-suspended particulate matter aggregation--a natural process of cleansing spilled oil in the aquatic environment.

    Sun, Juan; Zheng, Xilai


    It has been acknowledged that following an oil spill in coastal areas where suspended particulate matter (SPM) is rich, aggregation between oil and SPM can be naturally formed. This kind of aggregation product is termed as oil-SPM aggregates (OSAs). Because OSAs are not as sticky to the shorelines as crude oil and the oil-water contact area is greatly increased due to the formation of OSAs, both oil dispersion into the water body and oil biodegration would be significantly enhanced. In this review article, the authors (1) describe in detail the mechanism of OSA formation and controlling parameters which can influence OSA formation (the parameters discussed include the oil nature and properties, sediment types and concentrations, and the environmental factors such as salinity, temperature and mixing energy); (2) briefly review qualitative and quantitative methods used for characterization of OSA formation (two main methods used for the OSA characterization are the UV epi-fluorescence microscopy and gas chromatography equipped with flame ionization detector (GC-FID); (3) elucidate the applications of OSA formation in oil spill response strategies including natural attenuation, sediment relocation, and sediment mixing; and (4) discuss research needs in the future which would further improve our understanding of OSA formation and move towards the development of adequate oil behaviour models.

  15. Effect of meteorologic conditions on total suspended particulate (TSP) levels and elemental concentration of aerosols in a semi-arid zone (Beer-Sheva, Israel)

    Kushelevsky, A.; Shani, G.; Haccoun, A. (Ben-Gurion Univ. of the Negev, Beersheba (Israel). Dept. of Nuclear Engineering)


    The total suspended particulate (TSP) levels in Beer-Sheva, situated in a semi-arid area with winds bringing in dust from the surrounding deserts, was measured 41 times between June 1977 and May 1978. The TSP levels are correlated with climatic conditions. High TSP levels (890 +- 250 m-/sup 3/) were found during Sharav conditions and sandstorms (hot, dry weather, typical to this region). Low TSP levels (59 +- 28 m-/sup 3/) were found in the winter following rain. Usual TSP levels were found to be 140 +- 20 m-/sup 3/ occurring during normal weather conditions. The elemental composition of the Beer-Sheva aerosols were determined using instrumental neutron activation analysis (INNA) and X-ray Fluorescence (XRF). The concentrations of the following elements Fe, Na, Br, K, Sm, Au, Sb, Ga, La, Yb, Lu, Se, Hg, Cr, Sc, Rb, Co, Ta and Zn were determined by INNA and Ca, Si, S, Ti, Cl, Pb, Fe, V, Ni and Mn by XRF. Their relative abundances were found to depend on the prevailing TSP level.

  16. Size distributions of coastal ocean suspended particulate inorganic matter: Amorphous silica and clay minerals and their dynamics

    Zhang, Xiaodong; Stavn, Robert H.; Falster, Alexander U.; Rick, Johannes J.; Gray, Deric; Gould, Richard W.


    Particulate inorganic matter (PIM) is a key component in estuarine and coastal systems and plays a critical role in trace metal cycling. Better understanding of coastal dynamics and biogeochemistry requires improved quantification of PIM in terms of its concentration, size distribution, and mineral species composition. The angular pattern of light scattering contains detailed information about the size and composition of particles. These volume scattering functions (VSFs) were measured in Mobile Bay, Alabama, USA, a dynamic, PIM dominated coastal environment. From measured VSFs, we determined through inversion the particle size distributions (PSDs) of major components of PIM, amorphous silica and clay minerals. An innovation here is the extension of our reported PSDs significantly into the submicron range. The PSDs of autochthonous amorphous silica exhibit two unique features: a peak centered at about 0.8 μm between 0.2 and 4 μm and a very broad shoulder essentially extending from 4 μm to >100 μm. With an active and steady particle source from blooming diatoms, the shapes of amorphous silica PSDs for sizes 10 μm inside the bay, likely due to wind-induced resuspension of larger frustules that have settled. Compared to autochthonous amorphous silica, the allochthonous clay minerals are denser and exhibit relatively narrower PSDs with peaks located between 1 and 4 μm. Preferential settling of larger mineral particles as well as the smaller but denser illite component further narrowed the size distributions of clay minerals as they were being transported outside the bay. The derived PSDs also indicated a very dynamic situation in Mobile Bay when a cold weather front passed through during the experiment. With northerly winds of speeds up to 15 m s-1, both amorphous silica and clay minerals showed a dramatic increase in concentration and broadening in size distribution outside the exit of the barrier islands, indicative of wind-induced resuspension and subsequent

  17. Investigation of respirable particulate matter pollutants on air-breathing zone workers in the Beam Rolling Mills Factory (Iran National Steel Industrial Group, Ahvaz, Iran

    Rafiei Masoud


    Full Text Available Workers of iron and steel factories are exposed to a wide range of pollutants depending on the particular process, the materials involved, the effectiveness of monitoring and the control measures. Adverse effects are determined by the physical state and propensities of the pollutant involved, the intensity and duration of the exposure, the extent of pollutant accumulation in the body and the sensitivity of the individual to its effects. The main aim of this study is to assess the levels of the indoor respirable particulate matter (RPM and to compare the health condition of exposed workers, with nonexposed employees group. Line 630 has only one furnace of 40 tons and line 650 has two furnaces of 20 and 40 tons capacity due to which the mean of the RPM concentrations in the breathing zone was significantly different ( P < 0.05 in line 650 but not in line 630 as compared with National Institute for Occupational Safety and Hygiene′s (3 mg/m 3 . The average of the RPM concentrations in production line 650 is higher than that of production line 630, with the 95% confidence interval in saw cabin station number 1 of production line 650.

  18. Temporal occurrence and sources of persistent organic pollutants in suspended particulate matter from the most heavily polluted river mouth of Lake Chaohu, China.

    Liu, Cheng; Zhang, Lei; Fan, Chengxin; Xu, Fuliu; Chen, Kaining; Gu, Xiaozhi


    The Nanfei River is by many measures the most heavily polluted tributary to Lake Chaohu. In this study, the temporal occurrence and sources of four classes of persistent organic pollutants (POPs), including polycyclic aromatic hydrocarbons (PAHs), organochlorine pesticides (OCPs), polybrominated diphenyl ethers (PBDEs), and polychlorinated biphenyls (PCBs), in suspended particulate matter (SPM) from the river mouth were investigated monthly during 2014. Results show that concentrations of all four POPs in SPM were higher than those in the sediment of Lake Chaohu. PBDEs (26.7 ng g(-1) dry weight (dw)) were originated mainly from commercial deca-BDE mixtures. PCB concentrations (1.336 ng g(-1) dw) were lower than those of sediments in many other water bodies worldwide. PAHs (2597 ng g(-1) dw) and OCPs (57.38 ng g(-1) dw) were the most common POPs. PAHs mainly had high molecular weights and originated from pyrolytic sources, with a small proportion of petrogenic origin. The predominant OCPs were DDTs, heptachlorepoxides, dieldrin, hexachlorocyclohexanes, hexachlorobenzene, and chlordanes. Most OCPs originated from historical use, except lindane. Generally, of all the POPs studied, those of primary ecological concern should be acenaphthene, fluorene, DDTs, and chlordanes. Higher concentrations of POPs were detected during winter and spring than in summer and autumn, probably because of the high river flow during the rainy season. The high concentration of POPs in the riverine SPM and the fractionation of POPs in the water and SPM of the river should be a focal point in the future study of Lake Chaohu. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Development of a Semi-Analytical Algorithm for the Retrieval of Suspended Particulate Matter from Remote Sensing over Clear to Very Turbid Waters

    Bing Han


    Full Text Available Remote sensing of suspended particulate matter, SPM, from space has long been used to assess its spatio-temporal variability in various coastal areas. The associated algorithms were generally site specific or developed over a relatively narrow range of concentration, which make them inappropriate for global applications (or at least over broad SPM range. In the frame of the GlobCoast project, a large in situ data set of SPM and remote sensing reflectance, Rrs(λ, has been built gathering together measurements from various coastal areas around Europe, French Guiana, North Canada, Vietnam, and China. This data set covers various contrasting coastal environments diversely affected by different biogeochemical and physical processes such as sediment resuspension, phytoplankton bloom events, and rivers discharges (Amazon, Mekong, Yellow river, MacKenzie, etc.. The SPM concentration spans about four orders of magnitude, from 0.15 to 2626 g·m−3. Different empirical and semi-analytical approaches developed to assess SPM from Rrs(λ were tested over this in situ data set. As none of them provides satisfactory results over the whole SPM range, a generic semi-analytical approach has been developed. This algorithm is based on two standard semi-analytical equations calibrated for low-to-medium and highly turbid waters, respectively. A mixing law has also been developed for intermediate environments. Sources of uncertainties in SPM retrieval such as the bio-optical variability, atmospheric correction errors, and spectral bandwidth have been evaluated. The coefficients involved in these different algorithms have been calculated for ocean color (SeaWiFS, MODIS-A/T, MERIS/OLCI, VIIRS and high spatial resolution (LandSat8-OLI, and Sentinel2-MSI sensors. The performance of the proposed algorithm varies only slightly from one sensor to another demonstrating the great potential applicability of the proposed approach over global and contrasting coastal waters.

  20. PAH occurrence in chalk river systems from the Jura region (France). Pertinence of suspended particulate matter and sediment as matrices for river quality monitoring.

    Chiffre, Axelle; Degiorgi, François; Morin-Crini, Nadia; Bolard, Audrey; Chanez, Etienne; Badot, Pierre-Marie


    This study investigates the variations of polycyclic aromatic hydrocarbon (PAH) levels in surface water, suspended particulate matter (SPM) and sediment upstream and downstream of the discharges of two wastewater treatment plant (WWTP) effluents. Relationships between the levels of PAHs in these different matrices were also investigated. The sum of 16 US EPA PAHs ranged from 73.5 to 728.0 ng L(-1) in surface water and from 85.4 to 313.1 ng L(-1) in effluent. In SPM and sediment, ∑16PAHs ranged from 749.6 to 2,463 μg kg(-1) and from 690.7 μg kg(-1) to 3,625.6 μg kg(-1), respectively. Investigations performed upstream and downstream of both studied WWTPs showed that WWTP discharges may contribute to the overall PAH contaminations in the Loue and the Doubs rivers. Comparison between gammarid populations upstream and downstream of WWTP discharge showed that biota was impacted by the WWTP effluents. When based only on surface water samples, the assessment of freshwater quality did not provide evidence for a marked PAH contamination in either of the rivers studied. However, using SPM and sediment samples, we found PAH contents exceeding sediment quality guidelines. We conclude that sediment and SPM are relevant matrices to assess overall PAH contamination in aquatic ecosystems. Furthermore, we found a positive linear correlation between PAH contents of SPM and sediment, showing that SPM represents an integrating matrix which is able to provide meaningful data about the overall contamination over a given time span.

  1. Distribution of heavy metals in the water column,suspended particulate matters and the sediment under hydrodynamic conditions using an annular flume

    Jianzhi Huang; Xiaopeng Ge; Dongsheng Wang


    Sediment resuspension plays an important role in the transport and fate of heavy metals in the aquatic environment.In the present study,the release and binding forms of Cr,Cu,Zn,Pb under hydrodynamic conditions were investigated using an annular flume.Two sediments located at YLZ and GBD from Liangshui River,Beijing were resuspended for 10 hr at 0.159 and 0.267 m/see,respectively.The concentrations of suspended particulate matters of YLZ were higher than those of GBD during resuspension,indicating that the former sediment is more sensitive to the velocity.Crin the dissolved phase stayed nearly constant at about 2.25 and 1.84 μg/L for YLZ and GBD,respectively,due to the high percentage of its stable binding fractions in both sediments,while Cu,Zn,and Pb showed a fast release in the initial period of time.However,their concentrations in SPM generally decreased with time and were higher at the lower velocity of 0.159 m/see,which resulted from the entrainment and depressing effect of larger size particles with lower heavy metal content,commonly referred to as the "particle concentration effect".In addition,the binding form and heavy metal fractions were also found to vary during the resuspension event.A decrease in the sulphide/organic matters bounded form in GBD sediment was observed,whereas no visible changes were perceived in YLZ site samples.This phenomenon is due to the oxidation of heavy metal-sulphide binding forms,which originated from its high acid volatile sulphide content in GBD sediment.

  2. Occurrence and seasonal loads of pesticides in surface water and suspended particulate matter from a wetland of worldwide interest--the Ria Formosa Lagoon, Portugal.

    Cruzeiro, Catarina; Pardal, Miguel Ângelo; Rocha, Eduardo; Rocha, Maria João


    Two novel methods were developed to extract and quantify 56 pesticides in surface waters, considering their content in both dissolved aqueous phase (DAP) and suspended particulate matter (SPM) fractions. These procedures were applied to coastal samples taken seasonally during 2012-2013, from three strategic sampling sites along the Ria Formosa Lagoon (south of Portugal). Briefly, 500 mL of water samples were filtrated, separating both fractions. The DAP fraction was extracted and pre-concentrated by solid-phase extraction (SPE), while the SPM was extracted using ultrasonic extraction technique (USE). Both fractions were then analyzed, and the pesticides were quantified and identified, within 35 min, by gas chromatography (GC) coupled to mass spectrometry (GC-MS and GC-MS/MS), respectively. The extraction of pesticides from the SPM fraction showed average recoveries of 102%, detection limits below 2.2 ng/L, and quantification limits ranging from 0.3 to 6.6 ng/L. Considering the real water samples, 73% of the selected pesticides were quantified in both DAP and SPM fractions (ΣDAP+SPM 2.3 μg/L) and their maximum levels were measured in autumn and winter. By category, the global loads of fungicides, herbicides, and insecticides were ≈407, ≈323, and ≈1.6 μg/L, respectively. Thirty-one percent of the quantified pesticides exceeded the European directives levels (2008/105/EC and 98/83/EC). From the total loads, the SPM fraction contribution was 32%, showing the importance of measuring pesticides in that fraction. The water physicochemical parameters revealed that the total nitrogen amounts were very high relatively to the legal required values, mainly close to the city of Faro (2.6 mg/L). In light of the above, measures are in need to meet European directives and protect both fauna and humans that use this area for leisure.

  3. Polybrominated diphenyl ethers (PBDEs) in the surface sediments and suspended particulate matter (SPM) from Lake Chaohu, a large shallow Chinese lake.

    He, Wei; Qin, Ning; Kong, Xiangzhen; Liu, Wenxiu; He, Qishuang; Ouyang, Huiling; Wang, Qingmei; Yang, Bin; Yang, Chen; Jiang, Yujiao; Xu, Fuliu


    Suspended particulate matter (SPM) and surface sediment samples were collected from Lake Chaohu to investigate the residues, congener profile, and spatial distribution of polybrominated diphenyl ethers (PBDEs) in a large shadow lake in the middle of the Yangtze River Basin. The concentration of Σ13BDEs (defined as the sum of 13 target congeners excluding BDE 209) and the concentration of BDE 209 ranged from 236.7 to 1373.4 pg/g dry weight (dw) and from 4.2 to 691.2 pg/g dw in the surface sediments, respectively, which were 2-3 orders of magnitude smaller than those found in the SPM. The congener composition was dominated by BDE 47 (50.8%) and BDE 209 (21.3%) in the sediment, while the proportion of BDE 47 to Σ14BDEs in the SPM was slightly higher than that in the sediment. The concentration of Σ14BDEs in the sediment from the drinking water source (WR) area in the eastern part of the lake was very low, with a mean value of 514.8 pg/g, whereas the mean concentration was 102.4 ng/g in the SPM. A cluster analysis (CA) was conducted to further illustrate the dominance of each congener and the similarity of each sampling site. Many factors, including resuspension, photodecomposition, microbial oxidation, local discharge, and dredging, influenced the distribution in the sediment and SPM for the PBDE congeners as well as the spatial distribution of PBDEs. A formula for the PBDE concentrations in the surface sediment and SPM was constructed to understand the potential relationship between sediment and SPM concentrations. Although the formula did not accurately predict specific PBDE congener concentrations in the sediment, it remains a practical and useful way to assess the overall pollution of PBDE in sediment in Lake Chaohu, as it depends only on the concentrations of PBDEs in the SPM.

  4. Effect-directed analysis of Ah receptor-mediated activities caused by PAHs in suspended particulate matter sampled in flood events.

    Wölz, J; Brack, W; Moehlenkamp, C; Claus, E; Braunbeck, Th; Hollert, H


    Suspended particulate matter (SPM) sampled during a flood event in the year 2004 at the rivers Neckar and Rhine (Southwest Germany) was assessed for aryl hydrocarbon receptor (AhR)-mediated activities using EROD induction in the rainbow trout liver cell line RTL-W1. All EROD inductions were normalized to the positive control TCDD and given as bio-TEQ values. Since all samples indicated elevated AhR-mediated toxicities, an effect-directed analysis (EDA) was applied to identify substances causing the effects. In three primary fractions (F1 to F3) non-polar aliphatics, non-polar aromatic substances and more polar substances were separated. Fraction F2, co-eluting with non-polar polyaromatic substances (PACs) including polycyclic aromatic hydrocarbons (PAHs) gave highest AhR-agonistic effects and, thus, were sub-fractionated into seven secondary fractions (F2-1 to F2-7). Fraction F2-1, co-eluting with PCBs and PCDD/Fs, did not cause AhR-agonist activities. F2-2 to F2-4 containing PACs of less than 16 aromatic C-atoms produced minor activities. Highest inductions were detected with fraction F2-5 to F2-7, containing substances of more than 16 aromatic C-atoms (bio-TEQs up to approximately 4500 pg/g). Concentrations and relative potencies (REPs) of priority EPA-PAHs allowed the calculation of chemical toxicity equivalent concentrations (chem-TEQ values). Based on the chem-TEQs, EPA-PAHs explained between 5 and 58% of crude extract bio-TEQs from both rivers. Whereas fractions F2-1 to F2-4 indicated no biological activities, EPA-PAHs in fraction F2-5 to F2-7 accounted for 2 to 137% of AhR-related activities. Copyright 2010 Elsevier B.V. All rights reserved.

  5. Benzotriazole UV stabilizers in sediments, suspended particulate matter and fish of German rivers: New insights into occurrence, time trends and persistency.

    Wick, Arne; Jacobs, Björn; Kunkel, Uwe; Heininger, Peter; Ternes, Thomas A


    Benzotriazole UV stabilizers (BUVSs) are widely applied in plastics to prevent discoloration and to enhance product stability. This study describes for the first time the occurrence of nine different lipophilic BUVSs (UV-326, UV-320, UV-329, UV-350, UV-328, UV-327, UV-928, UV-234 and UV-360) in sediment, suspended particulate matter (SPM) and bream liver samples of German rivers. All investigated BUVSs were detected in sediments and SPM at concentrations in the low ng/g dry weight (dw) range. The so far rarely analyzed compound UV-360 as well as UV-326 were the predominant BUVSs in sediments and SPM from the river Rhine reaching maximum concentrations of 62 and 44 ng/g dw, respectively. Five BUVSs were also confirmed to bioaccumulate in bream liver, but neither UV-360 nor UV-326 was detected above the limit of quantification (LOQ). In contrast, highest concentrations in bream liver were determined for UV-327 (65 ng/g dw) and UV-328 (40 ng/g dw). A retrospective time trend analysis of BUVSs in SPM from two sites (river Rhine, 2005 to 2013; river Saar, 2006 to 2013) revealed increasing contamination levels of UV-329 and decreasing levels of UV-320 and UV-350. At one site (river Rhine) time trends of BUVS concentrations were also investigated in bream liver (1995-2013) and supported a considerably reduced exposure to UV-350. A first assessment of the environmental fate of BUVSs by sediment-water batch systems revealed a rapid partitioning into the sediment and no considerable degradation within 100 d. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Respiratory diseases in preschool children in the city of Niš exposed to suspended particulates and carbon monoxide from ambient air

    Đorđević Amelija


    Full Text Available Background/Aim. Analysis of air quality in Serbia indicates that the city of Niš belongs to a group of cities characterized by the third category of air quality (excessive air pollution. The aim of the study was to analyze the degree of causality between ambient air quality affected by particulate matter of 10 μm (PM10 and carbon monoxide (CO and the incidence of respiratory diseases in preschool children in the city of Niš. Methods. We quantified the influence of higher PM10 concentrations and carbon monoxide comprising motor vehicle exhausts in the city of Niš on the occurrence of unwanted health effects in preschool children by means of the hazard quotient (HQ, individual health risk (Ri, and the probability of cancer (ICR. The methodology used was according to the US Environmental Protection Agency (EPA, and it included basic scientific statistical methods, compilation methods, and the relevant mathematical methods for assessing air pollution health risk, based on the use of attribute equations. Results. Measurement of ambient air pollutant concentrations in the analyzed territory for the entire monitoring duration revealed that PM10 concentrations were significantly above the allowed limits during 80% of the days. The maximum measured PM10 concentration was 191.6 μg/m3, and carbon monoxide 5.415 mg/m3. The incidence of respiratory diseases in the experimental group, with a prominent impact of polluted air was 57.17%, whereas the incidence in the control group was considerably lower, 41.10 %. There were also significant differences in the distribution of certain respiratory diseases. Conclusion. In order to perform good causal analysis of air quality and health risk, it is very important to establish and develop a system for long-term monitoring, control, assessment, and prediction of air pollution. We identified the suspended PM10 and CO as ambient air pollutants causing negative health effects in the exposed preschool children

  7. Seasonal variations and evidence for the effectiveness of pollution controls on water-soluble inorganic species in total suspended particulates and fine particulate matter from Xi'an, China.

    Shen, Zhenxing; Arimoto, Richard; Cao, Junji; Zhang, Renjian; Li, Xuxiang; Du, Na; Okuda, Tomoaki; Nakao, Shunsuke; Tanaka, Shigeru


    Total suspended particulate (TSP) and particulate matter less than 2.5 microm in aerodynamic diameter (PM2.5) samples were collected over Xi'an for a 1-yr period to characterize the seasonal variations of water-soluble inorganic ions and to evaluate the effectiveness of the pollution policies and controls during the past 10 yr. Mass concentrations of five cations (sodium [Na+], potassium [K+], ammonium [NH4+], calcium [Ca2+], and magnesium [Mg2+]) and four anions (fluoride [F-], chloride [Cl-], nitrate [NO3-], and sulfate [SO4(2-)]) were determined by ion chromatography. The yearly arithmetic-mean mass concentrations of the total measured water-soluble ions in TSP and PM2.5 were 83.9 +/- 58.4 and 45 +/- 34.3 microg x m(-3). The most abundant ions in TSP were SO4(2-), NO3-, Ca2+, and NH4+; whereas in PM2.5 the dominant ions were SO4(2-), NH4 +, and NO3-. Most of the ions were more concentrated in the PM2.5 than in TSP, but two exceptions were Ca2+ and Mg2+. Comparisons of the molar ratios of Mg2+/Ca2+ in TSP indicated that fugitive dust was the main source for these two ions, and the influence of soil dust from outside of the city was most evident during dust storms. The mass concentrations of SO4(2-), NO3-, , NH4+, and K+ in TSP were highest in winter and lowest in spring, but Ca2+ was much higher in spring than other seasons because of suspended mineral dust. In PM2.5, NO3- and K+ also showed winter maxima, but SO4(2-) and NH4+ were highest in summer. Calculations of ion equivalents showed that TSP samples were more alkaline than PM2.5, the latter being weakly acidic in winter and autumn. High sulfur and nitrogen oxidation ratios occurred in summer and autumn, and there was evidence for the formation of ammonium bisulfate in TSP, ammonium sulfate in PM2.5, and ammonium nitrate in both fractions. Comparisons with the results of prior studies indicate that pollution controls in Xi'an have reduced the levels of air pollution over the past 10 yr. The SO4

  8. Pulmonary Oxidative Stress, Inflammation and Cancer: Respirable Particulate Matter, Fibrous Dusts and Ozone as Major Causes of Lung Carcinogenesis through Reactive Oxygen Species Mechanisms

    Spyridon Loridas


    Full Text Available Reactive oxygen or nitrogen species (ROS, RNS and oxidative stress in the respiratory system increase the production of mediators of pulmonary inflammation and initiate or promote mechanisms of carcinogenesis. The lungs are exposed daily to oxidants generated either endogenously or exogenously (air pollutants, cigarette smoke, etc.. Cells in aerobic organisms are protected against oxidative damage by enzymatic and non-enzymatic antioxidant systems. Recent epidemiologic investigations have shown associations between increased incidence of respiratory diseases and lung cancer from exposure to low levels of various forms of respirable fibers and particulate matter (PM, at occupational or urban air polluting environments. Lung cancer increases substantially for tobacco smokers due to the synergistic effects in the generation of ROS, leading to oxidative stress and inflammation with high DNA damage potential. Physical and chemical characteristics of particles (size, transition metal content, speciation, stable free radicals, etc. play an important role in oxidative stress. In turn, oxidative stress initiates the synthesis of mediators of pulmonary inflammation in lung epithelial cells and initiation of carcinogenic mechanisms. Inhalable quartz, metal powders, mineral asbestos fibers, ozone, soot from gasoline and diesel engines, tobacco smoke and PM from ambient air pollution (PM10 and PM2.5 are involved in various oxidative stress mechanisms. Pulmonary cancer initiation and promotion has been linked to a series of biochemical pathways of oxidative stress, DNA oxidative damage, macrophage stimulation, telomere shortening, modulation of gene expression and activation of transcription factors with important role in carcinogenesis. In this review we are presenting the role of ROS and oxidative stress in the production of mediators of pulmonary inflammation and mechanisms of carcinogenesis.

  9. [Grain Size Distribution Characteristics of Suspended Particulate Matter as Influenced by the Apparent Pollution in the Eutrophic Urban Landscape Water Body].

    Gong, Dan-yan; Pan, Yang; Huang, Yong; Bao, Wei; Li, Qian-qian


    Grain size distribution characteristics of suspended particulate matter (SPM) reflects the apparent polluted condition of the urban landscape water. In order to explore the internal relationship between the eutrophication of urban landscape water's apparent pollution and grain size distribution of SPM, and its influencing factors, this paper selected five representative sampling sites in Feng Jin River which is a typical eutrophication river in Suzhou City, measured the grain size distribution of SPM, sensation pollution index (SPI) and water quality index, and analyzed their correlation. The results showed that: The rich nutrient water possessed a similar characteristics in grain size distribution. The grain size distribution of SPM in water was multimodal, and the the peak position was roughly the same; the grain size distribution of SPM was composed by multiple components. It could be roughly divided into six parts with the particle size range of every group being 516 µm. The component III was superior (with an average volume fraction of 38.3%-43.2%), and its volume fraction had a significant positive relation with the SPI value and the Chl-a content. The increase of component III volume fraction was the reflection of particle size's result of increasing SPI value. The increase of component III volume fraction was mainly derived from the increasing algal content. The volume fraction of group IV + group VI + group V was significantly higher under the condition of exogenous enter. When there was no exogenous component, the volume fraction of group IV + group VI + group V had a significant negative correlation with SPI value; when there were exogenous components, the volume fraction of group IV + group VI + group V had a weak positive correlation with SPI value, but the correlation did not reach a significant level. Environmental factors (Fv/Fm and DO) and exogenous factors had an influence by functioning on the algal content which signified the polluted material

  10. Atmospheric Corrections and Multi-Conditional Algorithm for Multi-Sensor Remote Sensing of Suspended Particulate Matter in Low-to-High Turbidity Levels Coastal Waters

    Stéfani Novoa


    Full Text Available The accurate measurement of suspended particulate matter (SPM concentrations in coastal waters is of crucial importance for ecosystem studies, sediment transport monitoring, and assessment of anthropogenic impacts in the coastal ocean. Ocean color remote sensing is an efficient tool to monitor SPM spatio-temporal variability in coastal waters. However, near-shore satellite images are complex to correct for atmospheric effects due to the proximity of land and to the high level of reflectance caused by high SPM concentrations in the visible and near-infrared spectral regions. The water reflectance signal (ρw tends to saturate at short visible wavelengths when the SPM concentration increases. Using a comprehensive dataset of high-resolution satellite imagery and in situ SPM and water reflectance data, this study presents (i an assessment of existing atmospheric correction (AC algorithms developed for turbid coastal waters; and (ii a switching method that automatically selects the most sensitive SPM vs. ρw relationship, to avoid saturation effects when computing the SPM concentration. The approach is applied to satellite data acquired by three medium-high spatial resolution sensors (Landsat-8/Operational Land Imager, National Polar-Orbiting Partnership/Visible Infrared Imaging Radiometer Suite and Aqua/Moderate Resolution Imaging Spectrometer to map the SPM concentration in some of the most turbid areas of the European coastal ocean, namely the Gironde and Loire estuaries as well as Bourgneuf Bay on the French Atlantic coast. For all three sensors, AC methods based on the use of short-wave infrared (SWIR spectral bands were tested, and the consistency of the retrieved water reflectance was examined along transects from low- to high-turbidity waters. For OLI data, we also compared a SWIR-based AC (ACOLITE with a method based on multi-temporal analyses of atmospheric constituents (MACCS. For the selected scenes, the ACOLITE-MACCS difference was

  11. Fluidizing device for solid particulates

    Diebold, J.P.; Scahill, J.W.

    A flexible whip suspended in a hopper is caused to impact against fibrous and irregularly shaped particulates in the hopper to fluidize the particulates and facilitate the flow of the particulates through the hopper. The invention provides for the flow of particulates at a substantially constant mass flow rate and uses a minimum of energy.

  12. Urban sewage lipids in the suspended particulate matter of a coral reef under river influence in the South West Gulf of Mexico.

    Carreón-Palau, Laura; Parrish, Christopher C; Pérez-España, Horacio


    Nutritional quality of suspended particulate matter (SPM) and the degree of human fecal pollution in the largest coral reef system in the southwest Gulf of Mexico were evaluated using lipid classes, fatty acids (FA) and sterols in the dry and rainy seasons. High proportions of triacylglycerols and saturated and monounsaturated FA were detected in the SPM however it was considered poor quality because it had low proportions of highly unsaturated FA which can be used to determine production of marine biogenic material of dietary value to pelagic and benthic organisms. Urban sewage organic carbon was traced with coprostanol. The reference value of coprostanol from the point source of pollution was set using two samples from a sewage treatment plant processing waste from >140,000 people near the coral reef system, and it was contrasted with one river station and nine marine stations including six coral reefs. The concentration of coprostanol in the SPM was 3621 ± 98 ng L(-1) comprising 26% of total sterols. During the dry season, the river was contaminated upstream with human feces as evidenced by coprostanol at 1823 ng L(-1), the 5β-coprostanol: cholesterol ratio at 0.5, and 5β-coprostanol: [5α-cholestanol+5β-coprostanol] at 0.7. In contrast, marine stations had concentrations of coprostanol lower than a suggested regulation limit for tropical marine coastal waters (30 ng L(-1)), ranging between 6 and 28 ng L(-1). During the rainy season a dilution effect was detected in the river, however significantly higher concentrations of coprostanol in the marine stations were detected ranging between 15 and 215 ng L(-1), higher than the tentative tropical regulation range (30-100 ng L(-1)). Among the reefs, the nearshore one, 14.3 km from the treatment plant, was more exposed to human-fecal pollution, and offshore reefs, >17.3 km from the plant, had a lower degree of contamination. Finally, only three stations were clearly uncontaminated during both

  13. 30 CFR 57.5044 - Respirators.


    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Respirators. 57.5044 Section 57.5044 Mineral... Agents, and Diesel Particulate Matter Radiation-Underground Only § 57.5044 Respirators. In environments exceeding 1.0 WL, miners shall wear respirators approved by NIOSH for radon daughters prior to July 10,...

  14. Temporal variability of organic micropollutants in suspended particulate matter of the River Elbe at Hamburg and the River Mulde at Dessau, Germany.

    Heemken, O P; Stachel, B; Theobald, N; Wenclawiak, B W


    The compound classes of n-alkanes, polycyclic aromatic hydrocarbons (PAHs), and a number of chlorinated hydrocarbons (CHs) in the River Elbe and its tributary Mulde were investigated on the basis of monthly mixed samples of suspended particulate matter (SPM). Covering the period from September 1994 to August 1995, samples from the River Elbe were taken at Hamburg, those from the River Mulde at Dessau. The samples were extracted by supercritical fluid extraction (SFE). Analysis of all substance groups were performed by highperformance liquid chromatography (HPLC), followed by gas chromatography with mass spectrometric detection (GC/MSD). As a statistical approach for the interpretation of data, hierarchical cluster analysis of the individual compound classes were performed to determine differences or similarities between the sampling sites Hamburg and Dessau to find spatial and seasonal concentration patterns. These analysis showed that, with a high significance, the concentration patterns of n-alkanes, PAHs, and CHs were sampling site-specific in both the Elbe and Mulde throughout the entire sampling period. In all cases, clustering of mostly consecutive months indicated continuous, slow changes of input, which moreover showed a constancy with respect to annual cycles. Correlation analysis of pollutant loads with different hydrographic parameters showed a number of linear dependencies of the contaminants with temperature, SPM content, and water discharge. Annual fluxes of particle-bound pollutants were calculated for each sampling site, taking into account the average monthly SPM levels and the water discharge. The particle-bound pollutant loads for the River Elbe at Hamburg were estimated to 13.4 t/a n-alkanes, 4.1 t/a PAHs, and 175. 8 kg/a CHs. The pollutant loads for the River Mulde at Dessau amounted 0.55 t/a n-alkanes, 0.14 t/a PAHs, and 15.5 kg/a CHs during the monitoring period. The input of n-alkanes originated from different sources. The n-alkane pattern

  15. Heavy metal in inhalable and respirable particles in urban atmosphere

    T.F. Ediagbonya


    Full Text Available Human activities in Sapele are veritable sources of particulate pollution which are exuded into the atmosphere. These activities include bush burning which is one of the pre-planting activities, transportation, gas flaring, incineration of wastes refuse disposal and the use of wood as a source of fuel. The objective of this study is to determine the concentration of the trace metal in particulate matter captured in glass fibre filter paper. High volume sampler was used to collect the respirable and inhalable suspended particulate matter at ten different sites located in Sapele, from December 2010 to April 2011. The foam and the glass fibre filter were analysed for nine (Mn, Ni, Cr, Cd, Zn, Cu, Co, Fe, and Pb respectively by Flame Atomic Absorption Spectrophotometer (FAAS. The concentration of the respirable particle ranged from 104.17 to 145.83ug/cubic meter while the inhalable concentration ranged from 166.67 to 812.50ug/cubic meter. From the analysis the element Cd was moderately enriched.

  16. Modeling Total Suspended Solids (TSS) Concentrations in Narragansett Bay.

    This work covers mechanistic modeling of suspended particulates in estuarine systems with an application to Narragansett Bay, RI. Suspended particles directly affect water clarity and attenuate light in the water column. Water clarity affects both phytoplankton and submerged aqua...

  17. 42 CFR 84.174 - Respirator containers; minimum requirements.


    ... 42 Public Health 1 2010-10-01 2010-10-01 false Respirator containers; minimum requirements. 84.174... Air-Purifying Particulate Respirators § 84.174 Respirator containers; minimum requirements. (a) Except as provided in paragraph (b) of this section each respirator shall be equipped with a...

  18. The Applicability of the Distribution Coefficient, KD, Based on Non-Aggregated Particulate Samples from Lakes with Low Suspended Solids Concentrations.

    Gormley-Gallagher, Aine Marie; Douglas, Richard William; Rippey, Brian


    Separate phases of metal partitioning behaviour in freshwater lakes that receive varying degrees of atmospheric contamination and have low concentrations of suspended solids were investigated to determine the applicability of the distribution coefficient, KD. Concentrations of Pb, Ni, Co, Cu, Cd, Cr, Hg and Mn were determined using a combination of filtration methods, bulk sample collection and digestion and Inductively Coupled Plasma-Mass Spectrometry (ICP-MS). Phytoplankton biomass, suspended solids concentrations and the organic content of the sediment were also analysed. By distinguishing between the phytoplankton and (inorganic) lake sediment, transient variations in KD were observed. Suspended solids concentrations over the 6-month sampling campaign showed no correlation with the KD (n = 15 for each metal, p > 0.05) for Mn (r2 = 0.0063), Cu (r2 = 0.0002, Cr (r2 = 0.021), Ni (r2 = 0.0023), Cd (r2 = 0.00001), Co (r2 = 0.096), Hg (r2 = 0.116) or Pb (r2 = 0.164). The results implied that colloidal matter had less opportunity to increase the dissolved (filter passing) fraction, which inhibited the spurious lowering of KD. The findings conform to the increasingly documented theory that the use of KD in modelling may mask true information on metal partitioning behaviour. The root mean square error of prediction between the directly measured total metal concentrations and those modelled based on the separate phase fractions were ± 3.40, 0.06, 0.02, 0.03, 0.44, 484.31, 80.97 and 0.1 μg/L for Pb, Cd, Mn, Cu, Hg, Ni, Cr and Co respectively. The magnitude of error suggests that the separate phase models for Mn and Cu can be used in distribution or partitioning models for these metals in lake water.

  19. 环首都圈植被分布与可吸入颗粒物的空间相关性%Spatial correlation between vegetation distribution and respirable particulate matter around capital region

    冯仲科; 毛海颖; 李虹


    With the increasing of the industrialization and urbanization, respirable particulate matter content in the air was increased, which caused serious damages to the surrounding environment of the capital region. In order to reduce the air pollution, analyzing the relationship between respirable particulate matter content in the air and vegetation cover is necessary. This paper researched and analyzed the relationship between respirable particulate matter and vegetation cover according to the region around the central capital , built the capital region with a virtual radius of 100km for the unit circle and divided the important factors such as vegetation, soil, environment, topography to different scales under rectangular grid. Five-year atmospheric pollutant data from 2008 to 2012 was used in this paper, which was provided by the Beijing Municipal Environmental Protection Bureau. The interpolation method of GS+software and Moran's index were used to analyze spatial autocorrelation of the above variable factors and to calculate the radius of spatial influence in the capital region. Based on a rectangular grid method and Moran’s index method, combined with SPSS software, this paper analyzed the distribution of vegetation and the concentration of respirable particulate matter in the air with the distance between the changes of the relationship. After Moran’s index derived vegetation distribution and respirable particulate matter in the region around the capital concluded between the grid scale with increasing autocorrelation reduced. Autocorrelation range of vegetation cover is 6620-7131 m, and respirable particulate matter from the relevant sphere influence is 2 998-6 864 m. The spatial correlation distance between vegetation distribution and respirable particulate matter effect 41.87 km through nonlinear regression analysis with SPSS software, the standard errors(P) are between 0.001-0.003, correlation coefficient R2are more than 80%, and therefore non

  20. Anthropogenic versus geogenic contribution to total suspended atmospheric particulate matter and its variations during a two-year sampling period in Beijing, China.

    Schleicher, Nina; Norra, Stefan; Chai, Fahe; Chen, Yizhen; Wang, Shulan; Stüben, Doris


    Weekly samples of total suspended particles in air (TSP) were taken in south-east Beijing for a two-year period continuously from August 2005 to August 2007. Mass concentrations varied between 76 and 1028 microg m(-3) with an average concentration of 370 microg m(-3) for the whole period. The chemical composition and the mass concentration of aerosols in combination with meteorological data are reflecting specific influences of distinct aerosol sources on the pollution of Beijing's atmosphere. Lead (Pb), titanium (Ti), zinc (Zn) and copper (Cu) concentrations were chosen as indicator elements for different sources. Their amounts considerably varied over the course of the year. Element ratios, such as Pb/Ti, supported the distinction between periods of predominant geogenic or anthropogenic caused pollution. However, the interactions between aerosols from different sources are numerous and aerosol pollution still is a big and complex challenge for the sustainable development of Beijing.

  1. Assessing and accounting for the impact of respiratory motion on FDG uptake and viable volume for liver lesions in free-breathing PET using respiration-suspended PET images as reference

    Li, Guang, E-mail:; Schmidtlein, C. Ross; Humm, John L. [Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, New York 10065 (United States); Burger, Irene A. [Department of Radiology, University Hospital of Zurich, CH-8091 Zurich (Switzerland); Ridge, Carole A.; Solomon, Stephen B. [Department of Radiology, Memorial Sloan-Kettering Cancer Center, New York, New York 10065 (United States)


    Purpose: To assess and account for the impact of respiratory motion on the variability of activity and volume determination of liver tumor in positron emission tomography (PET) through a comparison between free-breathing (FB) and respiration-suspended (RS) PET images. Methods: As part of a PET/computed tomography (CT) guided percutaneous liver ablation procedure performed on a PET/CT scanner, a patient's breathing is suspended on a ventilator, allowing the acquisition of a near-motionless PET and CT reference images of the liver. In this study, baseline RS and FB PET/CT images of 20 patients undergoing thermal ablation were acquired. The RS PET provides near-motionless reference in a human study, and thereby allows a quantitative evaluation of the effect of respiratory motion on PET images obtained under FB conditions. Two methods were applied to calculate tumor activity and volume: (1) threshold-based segmentation (TBS), estimating the total lesion glycolysis (TLG) and the segmented volume and (2) histogram-based estimation (HBE), yielding the background-subtracted lesion (BSL) activity and associated volume. The TBS method employs 50% of the maximum standardized uptake value (SUV{sub max}) as the threshold for tumors with SUV{sub max} ≥ 2× SUV{sub liver-bkg}, and tumor activity above this threshold yields TLG{sub 50%}. The HBE method determines local PET background based on a Gaussian fit of the low SUV peak in a SUV-volume histogram, which is generated within a user-defined and optimized volume of interest containing both local background and lesion uptakes. Voxels with PET intensity above the fitted background were considered to have originated from the tumor and used to calculate the BSL activity and its associated lesion volume. Results: Respiratory motion caused SUV{sub max} to decrease from RS to FB by −15% ± 11% (p = 0.01). Using TBS method, there was also a decrease in SUV{sub mean} (−18% ± 9%, p = 0.01), but an increase in TLG{sub 50%} (18

  2. Method for analysis of psychopharmaceuticals in real industrial wastewater and groundwater with suspended organic particulate matter using solid phase extraction disks extraction and ultra-high performance liquid chromatography/time-of-flight mass spectrometry.

    Křesinová, Zdena; Linhartová, Lucie; Petrů, Klára; Krejčová, Lucie; Šrédlová, Kamila; Lhotský, Ondřej; Kameník, Zdeněk; Cajthaml, Tomáš


    A rapid and reliable analytical method was developed for the quantitative determination of psychopharmaceuticals, their precursors and by-products in real contaminated samples from a pharmaceutical company in Olomouc (Czech Republic), based on SPE disk extraction and detection by ultra performance liquid chromatography, combined with time-of-flight mass spectrometry. The target compounds were quantified in the real whole-water samples (water including suspended particles), both in the presence of suspended particulate matter (SPM) and high concentrations of other organic pollutants. A total of nine compounds were analyzed which consisted of three commonly used antidepressants (tricyclic antidepressants and antipsychotics), one antitussive agent and five by-products or precursors. At first, the SPE disk method was developed for the extraction of water samples (dissolved analytes, recovery 84-104%) and pressurised liquid extraction technique was verified for solid matrices (sludge samples, recovery 81-95%). In order to evaluate the SPE disk technique for whole water samples containing SPM, non contaminated groundwater samples were also loaded with different amounts (100 and 300mgL(-1)) of real contaminated sludge originating from the same locality. The recoveries from the whole-water samples obtained by SPE disk method ranged between 67 and 119% after the addition of the most contaminated sludge. The final method was applied to several real groundwater (whole-water) samples from the industrial area and high concentrations (up to 10(3)μgL(-1)) of the target compounds were detected. The results of this study document and indicate the feasibility of the SPE disk method for analysis of groundwater.

  3. Nature and sources of suspended particulate organic matter in a tropical estuary during the monsoon and pre-monsoon: Insights from stable isotopes (delta 13C POC, delta 15 N TPN) and carbohydrate signature compounds

    Khodse, V.B.; Bhosle, N.B.

    sup(15)N sub(TPN), particulate carbohydrates (PCHO), particulate uronic acid (PUA), and particulate neutral carbohydrate (PNCHO) concentration and composition. POC and PCHO concentrations were influenced by cell numbers of bacteria and phytoplankton...

  4. Assessment of suspended dust from pipe rattling operations

    Park, Ju-Myon

    Six types of aerosol samplers were evaluated experimentally in a test chamber with polydisperse fly ash. The Andersen sampler overestimates the mass of small particles due to particle bounce between stages and therefore provides a conservative estimate of respirable particulate mass and thoracic particulate mass. The TSP sampler provides an unbiased estimate of total particulate mass. TSP/CCM provides no information below ESD 2 mum and therefore underestimates respirable particulate mass. The PM10 sampler provides a reasonable estimate of the thoracic particulate fraction. The RespiCon sampler provides an unbiased estimate of respirable, thoracic, and inhalable fractions. DustTrak and SidePak monitors provide relative particle concentrations instead of absolute concentrations because it could not be calibrated for absolute particle concentrations with varying particle shape, composition, and density. Six sampler technologies were used to evaluate airborne dust concentrations released from oilfield pipe rattling operations. The task sampled was the removal of scale deposited on the inner wall of the pipe before it was removed from service in a producing well. The measured mass concentrations of the aerosol samplers show that a Gaussian plume model is applicable to the data of pipe rattling operations for finding an attainment area. It is estimated that workers who remain within 1 m of the machine centerline and directly downwind have an 8-hour TWA exposure opportunity of (13.3 +/- 9.7) mg/m3 for the Mud Lake pipe scale and (11.4 +/- 9.7) mg/m3 for the Lake Sand pipe scale at 95% confidence. At distances more than 4 m downwind from the machine centerline, dust concentrations are below the TWA-TLV of 10 mg/m3 for the worker in both scales. At positions crosswind or upwind from the machine centerline there is no measurable exposure. Available data suggest that the attainment area for the public starts at about 9 m downwind from the machine centerline in both scales, as

  5. Application of in situ observations, high frequency radars, and ocean color, to study suspended matter, particulate carbon, and dissolved organic carbon fluxes in coastal waters of the Barents Sea - the NORDFLUX project

    Stramska, Malgorzata; Yngve Børsheim, Knut; Białogrodzka, Jagoda; Cieszyńska, Agata; Ficek, Dariusz; Wereszka, Marzena


    There is still a limited knowledge about suspended and dissolved matter fluxes transported from coastal regions into the open sea regions in the Arctic. The land/sea interface is environmentally important and sensitive to climate change. Important biogeochemical material entering the oceans (including carbon) passes through this interface, but too little is known about the efficiency of this transport. Our goal in the NORDFLUX program is to improve quantitative understanding of the environmental feedbacks involved in these processes through an interdisciplinary study with innovative in situ observations. Completed work includes two in situ experiments in the Norwegian fiord (Porsangerfjorden) in the summers of 2014 and 2015. Experiments used research boat for collection of water samples and in situ bio-optical data, an autonomous glider, mooring with T S sensors, and a high frequency radar system. We have used these data to derive spatial maps of water temperature, salinity, surface currents, chlorophyll fluorescence, dissolved organic matter (DOM) fluorescence, and inherent optical properties (IOPs) of the water. The interpretation of these data in terms of suspended matter concentration and composition is possible by in situ 'calibrations' using water samples from discrete hydrographic stations. Total suspended matter (TSM), particulate carbon (POC and PIC), and dissolved organic carbon (DOC) concentrations together with measured water currents will allow us to estimate reservoirs and fluxes. Concentrations and fluxes will be related to physical conditions and meteorological data. An important aspect of this project is the work on regional ocean color algorithms. Global ocean color (OC) algorithms currently used by NASA do not perform sufficiently well in coastal Case 2 waters. Our data sets will allow us to derive such local algorithms. We will then use these algorithms for interpretation of OC data in terms of TSM concentrations and composition and DOC. After

  6. Seasonal and spatial distribution of particulate organic matter in the Bay of Bengal

    Fernandes, L.; Bhosle, N.B.; Matondkar, S.G.P.; Bhushan, R.

    The temporal, spatial and depth related variation of suspended particulate organic matter (POM) in the Bay of Bengal are assessed in this paper. For this purpose, suspended particulate matter (SPM) samples were collected from eight depths (2 to 1000...

  7. Ambient Air Quality Assessment with Particular Reference to Particulates in Jharia Coalfield, Eastern India.

    Singh, Gurdeep; Roy, Debananda; Sinha, Sweta


    Jharia Coalfield is the critically polluted area with the intense mining and associated industrial activities. There has been widespread concern of particulate pollution with the alarming levels of Suspended Particulate Matter (SPM) and Respirable Particulate Matter (PM10 & PM2.5). Coke oven plants, coal washing, thermal power stations and associated activities coupled with the transportation activities, give rise to critical air pollution levels in the region. This study envisages the assessment of air pollution of the region with particular reference to SPM, PM10 and PM2.5. Eighteen monitoring stations were selected considering various sources of pollution such as mining, industrial, commercial and residential areas apart from siting criteria as per IS: 5182 Part XIV. Air quality monitoring was carried out following standard methodologies and protocols as per Central Pollution Control Board (CPCB)/ National Ambient Air Quality Standard (NAAQS) norms using Respirable Dust Samplers (RDS) and Fine Particulate Samplers (PM2.5 Samplers). This study reveals considerable load of particulates (SPM, PM10, PM 2.5) which exceed not only the NAAQS but also the coal mining areas standards of Jharia coalfield, thus falling under the category of critically polluted area. Air Quality Indexing has also been developed which provides a clear map of the deterioration of air quality and also presenting comparative ranking of all the monitoring locations with respect to air quality status in the study area.

  8. Modelling the light absorption properties of particulate matter forming organic particles suspended in seawater.Part 1. Model description, classification of organic particles, and example spectra of the light absorption coefficient and the imaginary part of the refractive index of particulate matter for phytoplankton cells and phytoplankton-like particles

    Bogdan Woźniak


    Full Text Available Data on organic substances in the sea are applied to distinguish hypothetical chemical classes and physical types of suspended particulate organic matter (POM in seawater. Spectra of the light absorption coefficients of particulate matter apm(λ and the imaginary refractive index n'p(λ, are assessed for some of these classes and types of POM in seawater, that is, for live phytoplankton cells and phytoplankton-like particles. The spectral characteristics of these coefficients are established and the probable ranges of variability of their absolute magnitudes defined on the basis of the mass-specific coefficients of light absorption by the various organic substances forming the particles. Also presented are mathematical relationships linking the coefficients apm(λ and n'p(λ for the various chemical classes of POM with their physical parameters, such as the relative contents of organic matter, water, air or some other gas. This article is part of a bio-optical study undertaken by the authors, the objective of which is to implement remote sensing techniques in the investigation of Baltic ecosystems (Woźniak et al. 2004.

  9. On the origin and variability of suspended particulate matter (PM1, PM2.5 and PM10) concentrations in Cyprus.

    Pikridas, Michael; Vrekoussis, Mihalis; Mihalopoulos, Nikolaos; Kizas, Christos; Savvides, Chrysanthos; Sciare, Jean


    The Eastern Mediterranean (EM) lies at the crossroad of three different continents (Europe, Asia, and Africa). EM is a densely populated region including several cities with 3M inhabitants or more (e.g. Athens, Istanbul, Izmir, and Cairo). It has been identified as the most polluted area in Europe with respect to particulate matter (PM) mainly due to the combination of high photochemical activity, which causes pollutants to oxidize and partitioning in the particle phase, with the elevated pollutants emissions from neighboring regions. In addition, the proximity to Africa and the Middle East allows frequent transport of dust particles. At the center of the Eastern Mediterranean lies the island of Cyprus, which has received very little attention regarding its PM levels despite being the location in Europe most frequently impacted by air masses from the Middle East. Herewith, we present a historical PM archive that spans 2 decades. It involves ongoing monitoring on a daily basis of particulate matter with diameters smaller than 10 μm (PM10), 2.5 μm (PM2.5), and 1 μm (PM1) conducted in at least one, of the 12 currently existing air quality stations in Cyprus since 1997, 2005, and 2009, respectively. The most extended PM datasets correspond a) to the Agia Marina Xyliatou (AMX) monitoring station established at a remote area at the foothills of mount Troodos and b) that of the inland capital, Nicosia. Based on this long-term dataset, the diurnal, temporal and annual variability is assessed. Prior to 2010, PM10 concentration at all sites remained relatively constant, but at different levels, violating the annual EU legislated PM10 limit of 40 μg m-3. Since 2010, coarse mode levels have decreased at all sites. The reported decrease was equal to 30% at AMX. As a result, since 2010 the observed levels comply with the EU legislation threshold. Satellite observations of Aerosol Optical Thickness (AOT) Moderate Resolution Imaging Spectroradiometer (MODIS) onboard NASA

  10. Influence of the drying step within disk-based solid-phase extraction both on the recovery and the limit of quantification of organochlorine pesticides in surface waters including suspended particulate matter.

    Günter, Anastasia; Balsaa, Peter; Werres, Friedrich; Schmidt, Torsten C


    In this study, 21 organochlorine pesticides (OCPs) were determined based on sample preparation using solid-phase extraction disks (SPE disks) coupled with programmable temperature vaporizer (PTV)-large-volume injection gas-chromatography mass spectrometry (LVI-GC-MS). The work includes a comprehensive testing scheme on the suitability of the method for routine analysis of surface and drinking water including suspended particulate matter (SPM) with regard to requirements derived from the European Water Framework Directive (WFD, Directive 2000/60/EC). SPM is an important reservoir for OCPs, which contributes to the transport of these compounds in the aquatic environment. To achieve the detection limits required by the WFD, a high pre-concentration factor during sample preparation is necessary, which was achieved by disk SPE in this study. The performance of disk SPE is strongly influenced by the drying step, which could be significantly improved by effective elimination of the residual water by combination of a high vacuum pump and a low humidity atmosphere. Detection limits of the WFD in the ng/L range were achieved by large volume injection of 100μL sample extract. The recoveries ranged from 82% to 117% with an RSD smaller than 13%. The applicability of this method to natural samples was tested for instrumental qualification and system suitability evaluation. Successful participation in an interlaboratory comparison proved the suitability of the method for routine analysis.

  11. The mismatch of bioaccumulated trace metals (Cu, Pb and Zn) in field and transplanted oysters (Saccostrea glomerata) to ambient surficial sediments and suspended particulate matter in a highly urbanised estuary (Sydney estuary, Australia).

    Lee, Jung-Ho; Birch, Gavin F


    A significant correlation between sedimentary metals, particularly the 'bio-available' fraction, and bioaccumulated metal concentrations in the native Sydney rock oyster (Saccostrea glomerata) tissues has been successfully demonstrated previously for Cu and Zn in a number of estuaries in New South Wales, Australia. However, this relationship has been difficult to establish in a highly modified estuary (Sydney estuary, Australia) where metal contamination is of greatest concern and where a significant relationship would be most useful for environmental monitoring. The use of the Sydney rock oyster as a biomonitoring tool for metal contamination was assessed in the present study by investigating relationships between metals attached to sediments and suspended particulate matter (SPM) to bioaccumulated concentrations in oyster tissues. Surficial sediments (both total and fine-fraction), SPM and wild oysters were collected over 3 years from three embayments (Chowder Bay, Mosman Bay and Iron Cove) with each embayment representing a different physiographic region of Sydney estuary. In addition, a transplant experiment of farmed oysters was conducted in the same embayments for 3 months. No relationship was observed between sediments or SPM metals (Cu, Pb and Zn) to tissue of wild oysters; however, significant relationship was observed against transplanted oysters. The mismatch between wild and farmed, transplanted oysters is perplexing and indicates that wild oysters are unsuitable to be used as a biomonitoring tool due to the involvement of unknown complex factors while transplanted oysters hold strong potential.

  12. Seasonal concentrations, contamination levels, and health risk assessment of arsenic and heavy metals in the suspended particulate matter from an urban household environment in a metropolitan city, Beijing, China.

    Yang, Y Y; Liu, L Y; Guo, L L; Lv, Y L; Zhang, G M; Lei, J; Liu, W T; Xiong, Y Y; Wen, H M


    The levels and health risks of arsenic and heavy metals (As, Ba, Cd, Co, Cr, Cu, Mn, Ni, Pb, and Zn) in the suspended particulate matter (SPM) collected from an urban household environment in Beijing of China for 12 months were investigated. The mean concentrations of the studied toxic elements were higher and lower than crustal abundance and PM2.5 in the urban outdoors of Beijing. The concentrations of the studied elements displayed significant seasonality. The highest concentrations of the total elements occurred in winter, followed by autumn, while the lowest concentrations were recorded in summer. Based on the calculated values of enrichment factor (EF) and geoaccumulation index (Igeo), the levels for As and Cu were heavily contaminated, while those for Cd, Pb, and Zn were extremely contaminated. As and Pb might pose risks to children and adults via ingestion exposure. The accumulative risks of multi-elements resulted from dermal contact and inhalation exposures were not negligible. More attention should be paid to reducing the non-carcinogenic and carcinogenic health risks posed by the toxic elements bound to urban household SPM particles via ingestion, inhalation, and dermal contact exposure.

  13. Partitioning of the Suspended Particulate Spectral Scattering Coefficient in Poyang Lake%鄱阳湖水体悬浮颗粒物散射光谱分解方法研究

    陈莉琼; 陈晓玲; 田礼乔; 邱凤


    A model for partitioning the paniculate scattering coefficient into the contributions of suspended mineral particle and organic particle was proposed based on the measured data. The independent variables, I. E. The concentrations of mineral particles and organic particles in this study, were used to determine the mass-specific scattering cross section with the concurrent total suspended paniculate scattering coefficients collected during the field trip in Poyang Lake 2009. Results show that the scattering spectra of inorganic particles and organic particles can be successful derived by the proposed model, and the reconstructed total paniculate scattering coefficients are in better agreement with the measured values by the ordinary least square linear regressioa For the whole South Poyang Lake, mean absolute percentage errors between the measured scattering coefficients and reconstructed value were less than 25% over the main remote sensing effective wavebands such as 440, 532, 555 and 676 run. A remarkable lower predicted error, which can be controlled within 15%, were found at all stations with higher concentration of total suspended matters, while the spectral partitioning is less efficient at stations with total suspended particle concentration less than 15 mg ? L-1. Paniculate scattering spectrum retrieved by RMA shows that illite and montmorillonite are the major constituents of inorganic matters which dominate the light scattering properties of Poyang Lake. It is possible that scattering spectrum partitioned by the model could infer the major effective components in waters, and could be used to predict particulate scattering properties for highly turbid waters.%内陆水体复杂性为水体悬浮颗粒物散射光谱分解带来难题,也制约着水色遥感理论算法的发展.以2009年鄱阳湖秋季观测数据为基础,提出一种二元简化主轴(ranged major axis,RMA)方法的水体悬浮颗粒物散射光谱分解模型,对鄱阳湖水体中悬

  14. 75 FR 20546 - Total Inward Leakage Requirements for Respirators


    ... HUMAN SERVICES 42 CFR Part 84 RIN 0920-AA33 Total Inward Leakage Requirements for Respirators AGENCY... Respirators,'' published in the Federal Register on October 30, 2009 (74 FR 56141). The comment period on this... total inward leakage (TIL) requirements for half-mask air-purifying particulate respirators approved...

  15. Lantana camara invasion in urban forests of an Indo–Burma hotspot region and its ecosustainable management implication through biomonitoring of particulate matter

    Prabhat Kumar Rai


    Full Text Available The present study was performed in urban forests of Aizawl, Mizoram, north east India falling under an Indo–Burma hot spot region of existing ecological relevance and pristine environment. The phytosociolology of invasive weeds has been studied, showing that Lantana camara was the most dominant invasive weed. Further, the air quality studies revealed high suspended particulate matter as well as respirable suspended particulate matter in the ambient air of Aizawl. Biomonitoring through plant leaves has been recognized as a recent thrust area in the field of particulate matter science. We aimed to investigate whether L. camara leaves may act as a biomonitoring tool hence allowing its sustainable management. The quantity of respirable suspended particulate matter and suspended particulate matter at four different sites were much higher than the prescribed limits of Central Pollution Control Board of India during the summer and winter seasons. The dust deposition of L. camara leaves was 1.01 mg/cm2 and, pertaining to the biochemical parameters: pH was 7.49; relative water content 73.74%; total chlorophyll 1.91 mg/g; ascorbic acid 7.06 mg/g; sugar 0.16 mg/g; protein 0.67 mg/g; catalase 30.76 U/mg protein; peroxidase 0.16 U/mg protein; and air pollution tolerance index was 12.91. L. camara was observed in the good category in anticipated performance index, which shows the tolerant and conditioning capacity of air pollution. Therefore, the present study recommends the use of L. camara as biomonitor that may further have sustainable management implications for an invasive plant.

  16. The fate of bisphenol A, 4-tert-octylphenol and 4-nonylphenol leached from plastic debris into marine water--experimental studies on biodegradation and sorption on suspended particulate matter and nano-TiO2.

    Staniszewska, Marta; Graca, Bożena; Nehring, Iga


    Experiments were carried out, the aim of which was to determine the leaching rates for bisphenol A (4,4'-(propane-2,2-diyl)diphenol - BPA), 4-tert-octylphenol (OP), 4-nonylphenol (NP) from polycarbonate and recycled tyre granules into the seawater. Additionally biodegradation, sorption on marine suspended particulate matter and sorption on various types of nano-TiO2 of BPA, OP, NP were studied. Experiments were carried out on plastics at various stages of degradation. The conducted experiment confirmed the flux of BPA, OP and NP from the studied plastics into seawater. The initial photodegradation of the plastic had a significant influence on the amount of the studied components released into water. During the first days of the experiment leaching was weaker from aged materials. After 60 days leaching of BPA and OP was higher for aged plastic compared to unaged. On average, suspension adsorbed OP, BPA and NP from seawater at respective levels of 37%, 75% and 100%. On the other hand, during biodegradation on average 25%, 9% and 2% of OP, BPA and NP respectively are removed from water. Nano-TiO2 of 21 nm pore size diameter adsorbed all the compounds more strongly than nano-TiO2 of 15 nm pores sized coated with Al and stearic acid. The strongest sorption (100%) on different types of nano-TiO2 was that of the most hydrophobic and more linear structured NP with just one phenol group. The weakest sorption was observed in the case of BPA, which is the least hydrophobic, and characterized by higher compared to NP and OP steric hindrance and electrostatic repulsion. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. Hourly atmospheric concentrations of Cs-134 and Cs-137 at monitoring stations for suspended particulate matter in and south of Fukushima after the Fukushima Daiichi Nuclear Power Plant accident

    Tsuruta, Haruo; Oura, Yasuji; Ebihara, Mitsuru; Ohara, Toshimasa; Nakajima, Teruyuki


    No data has been found of continuous monitoring of radioactive materials in the atmosphere in Fukushima area after the Fukushima Daiichi Nuclear Power Plant (FD1NPP) accident on March 11, 2011, although it greatly contributes to accurate evaluation of the internal exposure dose, to reconstruction of emission time series of released radionuclides, and to validation of numerical simulations by atmospheric transport models. Then, we have challenged to retrieve the radioactivity in atmospheric aerosols collected every hour on a filter tape of Suspended Particulate Matter (SPM) monitoring system with beta ray attenuation method used at air pollution monitoring stations in east Japan. A test measurement for hourly atmospheric concentrations of Cs-134 and Cs-137 was successfully performed with a Ge detector for the used filter tapes during March 15-23, 2011, at three stations in Fukushima City 60 km northwest of the FD1NPP and four stations in southwest Ibaraki prefecture more than 150 km southwest of the FD1NPP. The data in Fukushima City revealed high Cs-137 concentrations of 10-30 Bq m-3 from the evening of March 15 to the early morning of March 16, when a large amount of radioactive materials was simultaneously deposited on the land surface by precipitation according to the measurement of radiation dose rate. Higher Cs-137 concentrations of 10-50 Bq m-3 were also found from the afternoon of March 20 to the morning of March 21, and which could not be detected by the radiation dose rate due to no precipitation. In contrast, much higher concentrations with the maximum of 320 Bq m-3 in southwest Ibaraki than in Fukushima City were found on the morning of March 15 and 21 under strong temperature inversion near the surface. The polluted air masses with high radioactive materials were passed away within a few hours as a plume in southwest Ibaraki, while the high Cs-137 concentrations lasted for 10-16 hours in Fukushima City where the polluted air masses after their transport

  18. Monosaccharide composition of suspended particles from the Bay of Bengal

    Bhosle, N.B.; Sankaran, P.D.; Wagh, A.B.

    Neutral carbohydrates were determined as alditol acetates by capillary gas chromatography in the hydrolysates of suspended particulate samples (40) collected from 8 depths (approx 1 to 1,000 m) at 5 stations of the Bay of Bengal. Eight individual...

  19. International Odra project (IOP) 'Interdisciplinary German Polish studies on the behaviour of pollutants in the Oder system'. Sub project 4: the state of suspended particulate matter in the Odra River system. Final report

    Henning, K.H.; Damke, H.; Kasbohm, J.; Puff, T.; Breitenbach, E.; Theel, O.; Kiessling, A.


    The purpose of the present project was to characterise the pollutant freight of suspended matter and suspended-matter-borne sediments in the Oder river system on the basis of large samples drawn at selected sampling sites. One of the major goals was to assess and draw up a balance of the transport regime of suspended matter between the compartments water, suspended matter and sediments. Special attention was given to the composition and structure of suspended matter as well as to the distribution of trace elements in the various components. Furthermore, the study was intended to provide ecology-related information on the basis of selected biogenic components. Statements on the time course of pollution of estuarine waters and the Baltic Sea by way of the Oder can be derived from a characterisation of current fluviatile solids (suspended matter and suspended-matter-borne sediments) and determination of their quantitative proportions. The following research strategy was derived from these goals: for a characterisation of suspended matter in terms of composition, structure and biogenic origin it is necessary to determine the concentration of suspended matter, its granulometric composition, carbon and sulphur content, biogenic opal content, mineral content, phase composition, metal content, structure of suspended flakes and association of diatoms in the suspended flakes and on the periphyton. [German] Das Vorhaben ist darauf ausgerichtet, den Belastungszustand der Schwebstoffe und schwebstoffbuertigen Sedimente im Oderflusssystem anhand von Grossproben ausgewaehlter Probenahmeorte zu charakterisieren. Ein wesentliches Ziel ist die Beurteilung des Transportregimes der Schwebstoffe zwischen den Kompartimenten Wasser, Schwebstoff und Sediment sowie seine Bilanzierung. Dabei gilt die besondere Aufmerksamkeit der Zusammensetzung und der Struktur der Schwebstoffe sowie die Spurenelementspeziation an die unterschiedlichen Bestandteile. Weiterhin werden oekologische Aussagen

  20. Indoor-outdoor relationships of respirable sulfates and particles

    Dockery, Douglas W.; Spengler, John D.

    Indoor and outdoor concentrations of respirable particulates and sulfates have been measured in 68 homes in six cities for at least 1 yr. A conservation of mass model was derived describing indoor concentrations in terms of outdoor concentrations, infiltration and indoor sources. The measured data were analysed to identify important building characteristics and to quantify their effect. The mean infiltration rate of outdoor fine particulates was found to be approximately 70%. Cigarette smoking was found to be the dominant indoor source of respirable particulates. Increased indoor concentrations of sulfates were found to be associated with smoking and also with gas stoves. The effect of full air conditioning of the building was to reduce infiltration of outdoor fine particulates by about one half, while preventing dilution and purging of internally generated pollutants. The model for indoor respirable particulate and sulfate levels was found to compare well with measurements.

  1. The study on the distribution of suspended particulate matter in the Bohai Sea by remote sensing%渤海悬浮物分布的遥感研究

    崔廷伟; 张杰; 马毅; 赵文静; 孙凌


    利用渤海湾和莱州湾现场实测的悬浮物含量和光谱数据,建立了基于555和670 nm波段遥感反射率的悬浮物含量遥感反演模型.经检验,模型平均相对误差优于20%,对输入端误差不敏感.基于该模型,利用ENVISAT MERIS遥感数据,从空间分布格局、大风过程的短期扰动以及季节性差异等方面分析了渤海悬浮物的时空分布特征.(1)渤海悬浮物含量的高值区集中分布在莱州湾(尤其是黄河口和莱州湾湾底)和渤海湾沿岸,此外在辽东湾沿岸海域悬浮物含量也相对较高,而在渤海大部水体悬浮物含量较低.(2)大风过程可在短期内(约1~3 d)显著改变全渤海的悬浮物空间分布格局,其中渤海湾和莱州湾响应最为强烈,辽东湾响应相对较弱,这与其各自的水深条件、底质类型和悬浮物粒径等因素有关.(3)渤海悬浮物含量总体上呈春夏低、秋冬高的分布特征;季节性差异最显著的区域是渤海湾、莱州湾和辽东湾,差异性最小的是秦皇岛近岸海域;风力等气候因素是悬浮物分布呈现季节性差异的主要原因,入海径流是另一重要因素.%The statistical retrieval model for the content of suspended particulate matter (SPM) is developed based on the in situ measurements of SPM content and remote sensing reflectance spectra in the Bohai Gulf and the Laizhou Bay of the Bohai Sea in China.The model utilizes spectral information of bands at 555 and 670 nm and is proved to be insensitive to the input noise when bejing applied to the independent dataset.The spatio-temporal distribution characteristics of SPM in the Bohai Sea are analyzed in terms of the spatial pattern, the disturbance by sustaining strong wind and the seasonal variability.(1)The area with the highest content of SPM in the Bohai Sea is located in the Laizhou Bay and the coastal part of the Bohai Gulf The SPM content is also relatively high in the coastal part of the Liaodong Gulf The other

  2. Distribution, origin and transformation of amino sugars sand bacterial contribution to estuarine particulate organic matter

    Khodse, V.B.; Bhosle, N.B.

    Amino sugars including bacterial biomarker muramic acid(Mur) were investigated in suspended particulate matter(SPM) to understand their distribution, origin, and biogeochemical cycling and the contribution of bacteria to particulate organic matter...

  3. Distribution of particulate organic matter in Rajapur and Vagothan estuarines (west coast of India)

    Tulaskar, A.S.; Sawant, S.S.; Wagh, A.B.

    The distribution of particulate organic carbon (POC), particulate carbohydrates (PCHO) and particulate proteins (PP) in the suspended particulate matter was studied. The POC, PCHO and PP concentrations ranged from 176 to 883 mu g.l/1, 115 to 647 mu...

  4. Particulate Loads Caused by Wind Erosion in the Great Plains

    Hagen, Lawrence J.; Woodruff, Neil P.


    In this paper the annual flux of suspended particulates caused by wind erosion in the Great Plains is estimated. This study demonstrated that climate causes wide variations in air pollution from wind erosion. (BT)

  5. Particulate Matter Pollution and Population Exposure Assessment over Mainland China in 2010 with Remote Sensing

    Ling Yao


    Full Text Available The public is increasingly concerned about particulate matter pollution caused by respirable suspended particles (PM10 and fine particles (PM2.5. In this paper, PM10 and PM2.5 concentration are estimated with remote sensing and individual air quality indexes of PM10 and PM2.5 (IPM10 and IPM2.5 over mainland China in 2010 are calculated. We find that China suffered more serious PM2.5 than PM10 pollution in 2010, and they presented a spatial differentiation. Consequently, a particulate-based air quality index (PAQI based on a weighting method is proposed to provide a more objective assessment of the particulate pollution. The study demonstrates that, in 2010, most of mainland China faced a lightly polluted situation in PAQI case; there were three areas obviously under moderate pollution (Hubei, Sichuan-Chongqing border region and Ningxia-Inner Mongolia border region. Simultaneously, two indicators are calculated with the combination of population density gridded data to reveal Chinese population exposure to PM2.5. Comparing per capita PM2.5 concentration with population-weighted PM2.5 concentration, the former shows that the high-level regions are distributed in Guangdong, Shanghai, and Tianjin, while the latter are in Hebei, Chongqing, and Shandong. By comparison, the results demonstrate that population-weighted PM2.5 concentration is more in line with the actual situation.

  6. Particulate matter pollution and population exposure assessment over mainland China in 2010 with remote sensing.

    Yao, Ling; Lu, Ning


    The public is increasingly concerned about particulate matter pollution caused by respirable suspended particles (PM10) and fine particles (PM2.5). In this paper, PM10 and PM2.5 concentration are estimated with remote sensing and individual air quality indexes of PM10 and PM2.5 (IPM10 and IPM2.5) over mainland China in 2010 are calculated. We find that China suffered more serious PM2.5 than PM10 pollution in 2010, and they presented a spatial differentiation. Consequently, a particulate-based air quality index (PAQI) based on a weighting method is proposed to provide a more objective assessment of the particulate pollution. The study demonstrates that, in 2010, most of mainland China faced a lightly polluted situation in PAQI case; there were three areas obviously under moderate pollution (Hubei, Sichuan-Chongqing border region and Ningxia-Inner Mongolia border region). Simultaneously, two indicators are calculated with the combination of population density gridded data to reveal Chinese population exposure to PM2.5. Comparing per capita PM2.5 concentration with population-weighted PM2.5 concentration, the former shows that the high-level regions are distributed in Guangdong, Shanghai, and Tianjin, while the latter are in Hebei, Chongqing, and Shandong. By comparison, the results demonstrate that population-weighted PM2.5 concentration is more in line with the actual situation.

  7. Biomagnetic monitoring of particulate matter (PM through leaves of an invasive alien plant Lantana camara in an Indo-Burma hot spot region

    Prabhat Kumar Rai


    Full Text Available Present study was performed in urban forests of Aizawl, Mizoram, North East India falling under an Indo-Burma hot spot region of existing ecological relevance and pristine environment. Phyto-sociolology of invasive weeds has been performed and results revealed that Lantana camara was the most dominant invasive weed. Further, the air quality studies revealed high suspended particulate matter (SPM as well as respirable suspended particulate matter (RSPM in ambient air of Aizawl, Mizoram, North East India. Bio-magnetic monitoring through plant leaves has been recognised as recent thrust area in the field of particulate matter (PM science. We aimed to investigate that whether magnetic properties of Lantana camara leaves may act as proxy of PM pollution and hence an attempt towards it's sustainable management. Magnetic susceptibility (χ, Anhyste reticremanent magnetization (ARM and Saturation isothermal remanent magnetization (SIRM of Lantana camara plant leaves were assessed and concomitantly correlated these magnetic properties with ambient PM in order to screen this invasive plant which may act as proxy for ambient PM concentrations. Results revealed high χ, ARM, SIRM of Lantana camara leaves and moreover, these parameters were having significant and positive correlation with ambient SPM as well as RSPM. Therefore, present study recommended the use of Lantana camara as bio-magnetic monitor which may further have sustainable management implications of an invasive plant.

  8. Evaluation of diesel particulate matter sampling techniques

    Pretorius, CJ


    Full Text Available The study evaluated diesel particulate matter (DPM) sampling methods used in the South African mining industry. The three-piece cassette respirable, open face and stopper sampling methods were compared with the SKC DPM cassette method to find a...

  9. [Performance evaluation of two N95 filtering-facepiece respirators on decomposition products of sulfur hexafluoride].

    Zhu, X C; Lu, W; Nie, X Q; Zhou, M; Zhang, R B; Qin, S X; Chen, W H


    To assess the filtration efficiency of two N95 filtering-facepiece respirators (FFRs) for the decomposition products of sulfur hexafluoride (SF6). Two types of N95 FFRs (the particulate and the acid-proof respirators) were selected in this study. The decomposition products of SF6, including particles, hydrogen fluoride (HF) and sulfur dioxide (SO2) , were measured under experimental condition by using TSI PortaCount Plus, fluorine ion-selective electrodes and spectrophotometer separately. The filtration efficiency was then calculated and compared. Both two models of N95 respirators had lowest filtration efficiency larger than 95% for particles under airflow ranged from 10 to 95 L/min. When exposed to different concentrations of HF (low: 0.00~1.99 mg/m(3), middle: 2.00~3.99 mg/m(3), high: >4 mg/m(3)) , the acid-proof N95 respirator was more effective than the particulate respirator (P10.00 mg/m(3)) , the acid-proof respirator showed a high filtration efficiency within exposure to 1.5 hours: 95.73%, 98.67%, 98.14%, and 97.78%, respectively, when exposure duration extended to 4 hours, the filtration efficiency of the acid-proof respirator decreased to 91.97%, 82.28%, 70.12%, and 58.56%, respectively. Both the particulate and the acid-proof N95 FFRs met national standards on the particulate filtration efficiency. The acid-proof N95 respirator demonstrates to be more effective in filtering HF and SO2 than the particulate respirator. The filtration efficiency could decrease to an unsafe condition under longer exposure duration, timely replacement of respirator is recommended at the workplace.

  10. Synchronization of respiration

    Garssen, B.

    In order to study synchronization of respiration, three different videofragments were presented to 21 normal subjects. Each fragment showed a ‘therapeutic interview’ specially performed for this purpose, with a ‘patient’ breathing in a particular way. The respiration of model 1 was deep, slow and

  11. Suspended sediment dynamics on a seasonal scale in the Mandovi and Zuari estuaries, central west coast of India

    Rao, V.P.; Shynu, R.; Kessarkar, P.M.; Sundar, D.; Michael, G.S.; Narvekar, T.; Blossom, V.; Mehra, P.

    Suspended particulate matter (SPM) collected at regular stations from the Mandovi and Zuari estuaries indicates that the peaks of high SPM coincide with peaks of high rainfall and low salinity and also with peaks of moderate/low rainfall coupled...

  12. Sources and fate of organic matter in suspended and bottom sediments of the Mandovi and Zuari estuaries, Western India

    Shynu, R.; Rao, V.P.; Sarma, V.V.S.S.; Kessarkar, P.M.; ManiMurali, R.

    Organic carbon (OC), total nitrogen (TN) and stable carbon and nitrogen isotopic compositions were measured in suspended particulate matter (SPM) and surface sediment along estuaries of Mandovi and Zuari rivers, two small mountainous river systems...

  13. Understanding particulate coating microstructure development

    Roberts, Christine Cardinal

    How a dispersion of particulates suspended in a solvent dries into a solid coating often is more important to the final coating quality than even its composition. Essential properties like porosity, strength, gloss, particulate order, and concentration gradients are all determined by the way the particles come together as the coating dries. Cryogenic scanning electron microscopy (cryoSEM) is one of the most effective methods to directly visualize a drying coating during film formation. Using this method, the coating is frozen, arresting particulate motion and solidifying the sample so that it be imaged in an SEM. In this thesis, the microstructure development of particulate coatings was explored with several case studies. First, the effect of drying conditions was determined on the collapse of hollow latex particles, which are inexpensive whiteners for paint. Using cryoSEM, it was found that collapse occurs during the last stages of drying and is most likely to occur at high drying temperatures, humidity, and with low binder concentration. From these results, a theoretical model was proposed for the collapse of a hollow latex particle. CryoSEM was also used to verify a theoretical model for the particulate concentration gradients that may develop in a coating during drying for various evaporation, sedimentation and particulate diffusion rates. This work created a simple drying map that will allow others to predict the character of a drying coating based on easily calculable parameters. Finally, the effect of temperature on the coalescence and cracking of latex coatings was explored. A new drying regime for latex coatings was identified, where partial coalescence of particles does not prevent cracking. Silica was shown to be an environmentally friendly additive for preventing crack formation in this regime.

  14. Assessment of particulate matter variation during 2011-2015 over a tropical station Agra, India

    Gogikar, Priyanjali; Tyagi, Bhishma


    Air quality over Agra is deteriorating and causing a serious threat to people residing in the city as well as to World heritage site- Tajmahal. In the present study, daily average concentrations of Suspended Particulate Matter (SPM) and Respirable Suspended Particulate Matter (RSPM) were analysed over a period of 2011-2015 at four stations in Agra city, namely: Taj, Itmad-Ud-Daula, Rambagh and Nunhai. The concentrations are above threshold values when compared to specify standards for a healthy environment (by India, US, WHO, EU and China - Class I and Class II) for all the seasons except monsoon and the values are highest in the month of November and lowest in the month of August and September. Variation of RSPM and SPM were found to be positively correlated with each other with values of 0.76 (Taj), 0.72 (Itmad-Ud-Daula), 0.69 (Rambagh), 0.77 (Nunhai). The study illustrates that the levels of SPM and RSPM are not showing any decreasing trend over Agra even after closing of industries and taking other precautions inside the city by Government of India. The study clearly identifies that local control of pollution sources are not enough and pollution is being transported from nearby regions to keep the daily pollution value higher than threshold. Source regions of transported pollutants over Agra have been analysed by using Weighted Potential Source Contribution Function (WPSCF) for both SPM and RSPM. Wavelet analysis of monthly averaged values of RSPM and SPM data sets has shown the existence of semi-annual and annual periodicity over the study region.

  15. Growth and energetics in Spisula subtruncata (Da Costa) and the effect of suspended bottom material

    Møhlenberg, F.; Kiørboe, Thomas


    The influence of suspended bottom material (0-25 mg/l) and algal cells (Phaeodactylum tricornutum) (0-500 .mu.g dry org wt[organic weight]/l) on clearance, growth and energetics in S. subtruncata (da Costa) was studied. Clearance and respiration rate were independent of concentrations of algae...... and suspended bottom material. Algal ingestion rate was proportional to algal concentration and independent of the concentration of suspended bottom material. Growth rate increased with algal concentration and was further increased by 10-110% by adding suspended bottom material. The positive effect of suspended...... bottom material on growth is due to a higher efficiency of assimilation of the ingested algae and/or the utilization of organic matter in the suspended bottom material. The efficiency of algal assimilation decreased from 76% at a low (150 .mu.g dry org wt/l) to 33% at a high (500 .mu.g) algal...

  16. Respirator Fact Sheet

    ... have expiration dates that should be checked before purchase. Also, over time your mask can get old ... Respirator Fact Sheet [PDF - 706 KB] Follow NIOSH Facebook Flickr Pinterest Twitter YouTube NIOSH Homepage NIOSH A- ...

  17. Respiration in Aquatic Insects.

    MacFarland, John


    This article: (1) explains the respiratory patterns of several freshwater insects; (2) describes the differences and mechanisms of spiracular cutaneous, and gill respiration; and (3) discusses behavioral aspects of selected aquatic insects. (ML)


    DR. AMIN

    The calculated enrichment factor revealed Cd to be highly .... calculated by the following formular: SPM = Wp/Vair, ... Absorption Spectrophotometer (Buck Scientific Model -. 200A/213) with ... also be attributed to meteorological factors such as.

  19. Universal Spectrum for Atmospheric Suspended Particulates: Comparison with Observations

    Selvam, A M


    Atmospheric flows exhibit self-similar fractal space-time fluctuations on all space-time scales associated with inverse power law distribution for power spectra of meteorological parameters such as wind, temperature, etc. Fractal fluctuations imply long-range correlations, identified as self-organized criticality generic to dynamical systems in nature such as river flows, population dynamics, heart beat patterns etc., and are independent of the exact physical, chemical, physiological and other properties of the dynamical system. The physics of self-organized criticality is not yet identified. A general systems theory developed by the author visualizes the fractal fluctuations to result from the coexistence of eddy fluctuations in an eddy continuum, the larger scale eddies being the integrated mean of enclosed smaller scale eddies. The model predicts that the probability distributions of component eddy amplitudes and the corresponding variances (power spectra) are quantified by the same universal inverse power...

  20. Characterization and morphology of solids suspended in rain water; Caracterizacion y morfologia de solidos suspendidos en agua de lluvia

    Iturbe G, J.L.; Lopez M, B.E.; Torre O, J. De la [Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, Mexico D.F. (Mexico)


    This work presents the results obtained from the analysis of rain water in Mexico. The study treats over the characterization and morphology of the solids suspended in form of particles in the atmosphere. The solids suspended were obtained of the pluvial precipitations after these have been centrifuged. Subsequently of the separation, the particulate matter was analysed by Sem and X-ray dispersive energy.

  1. The nature and distribution of particulate matter in the Mandovi Estuary, central west coast of India

    Kessarkar, P.M.; Rao, V.P.; Shynu, R.; Mehra, P.; Viegas, B.E.

    in sedimentation was noted by Zabawa (1978), who showed that bacteria by attaching to suspended solids secrete a mucus slime of a sticky polysaccharides that not only holds particulates together (see Fig. 5g), but also traps isolated mineral grains...

  2. Thermal efficiency and particulate pollution estimation of four biomass fuels grown on wasteland

    Kandpal, J.B.; Madan, M. [Indian Inst. of Tech., New Delhi (India). Centre for Rural Development and Technology


    The thermal performance and concentration of suspended particulate matter were studied for 1-hour combustion of four biomass fuels, namely Acacia nilotica, Leucaena leucocepholea, Jatropha curcus, and Morus alba grown in wasteland. Among the four biomass fuels, the highest thermal efficiency was achieved with Acacia nilotica. The suspended particulate matter concentration for 1-hour combustion of four biomass fuels ranged between 850 and 2,360 {micro}g/m{sup 3}.

  3. Evaluation of the impact of storm event inputs on levels of gross primary production and respiration in a drinking water reservoir

    Samal, N. R.; Pierson, D. C.; Staehr, P. A.; Pradhanang, S. M.; Smith, D. G.


    Episodic inputs of dissolved and particulate material during storm events can have important effects on lake and reservoir ecosystem function and also impact reservoir drinking water quality. We evaluate the impacts of storm events using vertical profiles of temperature, dissolved oxygen, turbidity, conductivity and chlorophyll automatically collected at 6 hour intervals in Ashokan Reservoir, which is a part of the New York City drinking water supply. Storm driven inputs to the reservoir periodically result in large input of suspended sediments that result in reservoir turbidity levels exceeding 25 NTU, and substantial reductions in the euphotic depth. Dissolved materials associated with these same storms would be expected to stimulate bacterial production. This study involves the use of a conceptual model to calculate depth specific estimates of gross primary production (GPP) and ecosystem respiration (R) using three years of data that included 777 events that increased reservoir turbidity levels to over 25 NTU. Using data from before, during and after storm events, we examine how the balance between GPP and R is influenced by storm related increases in turbidity and dissolved organic matter, which would in turn influence light attenuation and bacterial production. Key words: metabolism, primary production, GPP, respiration, euphotic depth, storm event, reservoir

  4. Cattle respiration facility

    Hellwing, Anne Louise Frydendahl; Lund, Peter; Weisbjerg, Martin Riis


    In Denmark, the emission rate of methane from dairy cows has been calculated using the IPCC standard values for dairy cows in Western countries, due to the lack of national data. Therefore, four respiration chambers for dairy cows were built with the main purpose of measuring methane, but also...

  5. Growth and energetics in Spisula subtruncata (Da Costa) and the effect of suspended bottom material

    Møhlenberg, F.; Kiørboe, Thomas


    The influence of suspended bottom material (0-25 mg/l) and algal cells (Phaeodactylum tricornutum) (0-500 .mu.g dry org wt[organic weight]/l) on clearance, growth and energetics in S. subtruncata (da Costa) was studied. Clearance and respiration rate were independent of concentrations of algae...

  6. Mineralogy and geochemistry of atmospheric particulates in western Iran

    Ahmady-Birgani, Hesam; Mirnejad, Hassan; Feiznia, Sadat; McQueen, Ken G.


    This study investigates the mineralogy and physico-chemical properties of atmospheric particulates collected at Abadan (southwestern Iran) near the Persian Gulf coast and Urmia (northwestern Iran) during ambient and dust events over 6 months (winter 2011; spring 2012). Particle sizes collected were: TSP (total suspended particulates); PM10 (particulates Al, Mg, Na, Cl, P, S, Ca, K, Fe, Ti, and Si, mostly reflecting calcite, quartz, aluminosilicates, clays, gypsum and halite. Additionally, As, Pb, Zn, Mn, Sc, Nd, W, Ce, La, Ba and Ni were detected in TSP, PM10 and PM2.5 samples collected during dust events.

  7. Humanlike Articulate Robotic Headform to Replace Human Volunteers in Respirator Fit Testing


    reservoir or scrubbed CO2 in a rebreather.[8] The 1848 US patent[9] for Haslett’s Lung Protector describes the first air purifying respirator...N95 filtering facepiece particulate respirator and a surgical mask during human breathing: two pathways for particle penetration. J. Occup. Environ...Assoc. J, 1983. 44: 720–726. 39. Tuomi, T., Face seal leakage of half-masks and surgical masks. Am. Ind. Hyg. Assoc. J., 1985. 46(6): 308–312. 40

  8. Hydrolysis and degradation of filtrated organic particulates in a biofilm reactor under anoxic and aerobic conditions

    Janning, K.F.; Mesterton, K.; Harremoës, P.


    carbon to the bulk liquid was observed as an indication of hydrolysis taking place. The second experiment was designed as a series of on-line OUR batch experiments in a biofilm reactor with recirculation, in order to investigate further the degradation of particulate organic matter. After the biofilm had...... been starved in order to remove the original organic matter, particulate organic matter was added and the degradation kinetics recorded. The initial removal rate was high, r(A.O2) = 2.1 g O-2/(m(2)d) though fast declining towards endogenous respiration. The respiration ratio between removed oxygen...... and produced carbon dioxide was declining from 1.3 to 1.0 g O-2/g CO2 during the degradation of organic particulates. The respiration ratio during endogenous respiration was determined to be 0.7 g O-2/g CO2 indicating a thorough mineralisation of biomass. (C) 1997 IAWQ. Published by Elsevier Science Ltd....

  9. Genome-resolved metagenomics of a bioremediation system for degradation of thiocyanate in mine water containing suspended solid tailings.

    Rahman, Sumayah F; Kantor, Rose S; Huddy, Robert; Thomas, Brian C; van Zyl, Andries W; Harrison, Susan T L; Banfield, Jillian F


    Thiocyanate (SCN(-) ) is a toxic compound that forms when cyanide (CN(-) ), used to recover gold, reacts with sulfur species. SCN(-) -degrading microbial communities have been studied, using bioreactors fed synthetic wastewater. The inclusion of suspended solids in the form of mineral tailings, during the development of the acclimatized microbial consortium, led to the selection of an active planktonic microbial community. Preliminary analysis of the community composition revealed reduced microbial diversity relative to the laboratory-based reactors operated without suspended solids. Despite minor upsets during the acclimation period, the SCN(-) degradation performance was largely unchanged under stable operating conditions. Here, we characterized the microbial community in the SCN(-) degrading bioreactor that included solid particulate tailings and determined how it differed from the biofilm-based communities in solids-free reactor systems inoculated from the same source. Genome-based analysis revealed that the presence of solids decreased microbial diversity, selected for different strains, suppressed growth of thiobacilli inferred to be primarily responsible for SCN(-) degradation, and promoted growth of Trupera, an organism not detected in the reactors without solids. In the solids reactor community, heterotrophy and aerobic respiration represent the dominant metabolisms. Many organisms have genes for denitrification and sulfur oxidation, but only one Thiobacillus sp. in the solids reactor has SCN(-) degradation genes. The presence of the solids prevented floc and biofilm formation, leading to the observed reduced microbial diversity. Collectively the presence of the solids and lack of biofilm community may result in a process with reduced resilience to process perturbations, including fluctuations in the influent composition and pH. The results from this investigation have provided novel insights into the community composition of this industrially relevant

  10. Stable carbon isotopic composition of suspended particulate organic matter in the Prydz Bay and its adjacent areas%南极普里兹湾及其邻近海域悬浮颗粒有机物的碳同位素组成及其影响因素

    任春燕; 陈敏; 高众勇; 郭劳动; 贾仁明; 刘萧; 邱雨生; 郑敏芳


    To better understand carbon and particle dynamics in the Prydz Bay and its adjacent areas,stable carbon i-sotopic composition in suspended particulate organic matter (POM)along with aqueous CO2 ,nutrients and hydrog-raphic data were measured to examine the spatial and vertical distributions ofδ13 CPOC and their controlling factors during the 29th Chinese Antarctic Research Expedition.Furthermore,carbon isotope fractionation factor during the assimilation of dissolved inorganic carbon (DIC)by phytoplankton in the mixed layer was estimated.Our results showed thatδ13 CPOC ranged from -28.5‰ to -21.1‰ with an average of -24.6‰,showing an increase trend from the inner bay to open waters outside the Bay.Carbon isotope fractionation factor during phytoplankton DIC assimilation in the mixed layer was estimated to be 23.4‰ based on the relationship between δ13 CPOC and 1/[CO2(aq)],and was the major controlling factor forδ13 CPOC values in the mixed layer in the Prydz Bay and its adja-cent areas.Values ofδ13 CPOC increased in general with increasing depth in the study areas,ascribing to the isotope fractionation during POM remineralization.%依托中国第29次南极科学考察航次开展了南大洋普里兹湾及其邻近海域悬浮颗粒有机物碳同位素组成(δ13 CPOC )的研究,结合温度、盐度、营养盐和溶解 CO2的数据,揭示了影响研究海域颗粒有机物碳同位素组成的主控因素,计算出混合层中浮游植物吸收无机碳过程的碳同位素分馏因子。结果表明,普里兹湾及其邻近海域的δ13 CPOC 介于-28.5‰~-21.1‰,平均值为-24.6‰,表现出湾内大于湾外的特征。浮游植物同化吸收 CO2过程的碳同位素分馏是影响研究海域混合层δ13 CPOC 的主要因素,根据δ13 CPOC和1/[CO2(aq)]的线性拟合关系,计算出浮游植物同化吸收 CO2过程的碳同位素分馏因子εp 为23.4‰。δ13 CPOC的垂直分布随深度

  11. Dispersive suspended microextraction.

    Yang, Zhong-Hua; Liu, Yu; Lu, Yue-Le; Wu, Tong; Zhou, Zhi-Qiang; Liu, Dong-Hui


    A novel sample pre-treatment technique termed dispersive suspended microextraction (DSME) coupled with gas chromatography-flame photometric detection (GC-FPD) has been developed for the determination of eight organophosphorus pesticides (ethoprophos, malathion, chlorpyrifos, isocarbophos, methidathion, fenamiphos, profenofos, triazophos) in aqueous samples. In this method, both extraction and two phases' separation process were performed by the assistance of magnetic stirring. After separating the two phases, 1 μL of the suspended phase was injected into GC for further instrument analysis. Varieties of experiment factors which could affect the experiment results were optimized and the following were selected: 12.0 μL p-xylene was selected as extraction solvent, extraction speed was 1200 rpm, extraction time was 30 s, the restoration speed was 800 rpm, the restoration time was 8 min, and no salt was added. Under the optimum conditions, limits of detections (LODs) varied between 0.01 and 0.05 μg L(-1). The relative standard deviation (RSDs, n=6) ranged from 4.6% to 12.1%. The linearity was obtained by five points in the concentration range of 0.1-100.0 μg L(-1). Correlation coefficients (r) varied from 0.9964 to 0.9995. The enrichment factors (EFs) were between 206 and 243. In the final experiment, the developed method has been successfully applied to the determination of organophosphorus pesticides in wine and tap water samples and the obtained recoveries were between 83.8% and 101.3%. Compared with other pre-treatment methods, DSME has its own features and could achieve satisfied results for the analysis of trace components in complicated matrices.

  12. Aquatic macrophytes drive sediment stoichiometry and the suspended particulate organic carbon composition of a tropical coastal lagoon Macrófitas aquáticas determinam a estequiometria do sedimento e a composição do carbono orgânico particulado em suspensão de uma lagoa costeira tropical

    Cláudio Cardoso Marinho


    Full Text Available AIM: This research aimed to evaluate (1 the influence of the aquatic macrophytes Typha domingensis Pers., Eleocharis interstincta (Vahl Roem. & Schult. (emergent and Potamogeton stenostachys K. Schum. (submersed on sediment stoichiometry and (2 the contribution of these aquatic macrophytes to organic carbon composition in different compartments of a tropical coastal lagoon (Cabiúnas Lagoon, Macaé-RJ; METHODS: The concentration of carbon (C, nitrogen (N and phosphorus (P was determined in 2-cm intervals in the first 10 cm of sediment in both littoral and limnetic regions. In the littoral region, the sediment was collected in three different sites: T. domingensis, E. interstincta and P. stenostachys stands. In order to know the pathways of C in Cabiunas lagoon, the isotopic signature (δ13C of restinga terrestrial vegetation, zooplankton, phytoplankton, macrophytes, dissolved and suspended material on water were evaluated; RESULTS: The concentrations of C and N in the sediment of the E. interstincta and T. domingensis stands were significantly higher than in the sediment of the limnetic region. The concentration of phosphorus in the sediment colonized by T. domingensis was higher than in the limnetic region and in P. stenostachys stand. The highest molar C:P ratios were found in E. interstincta and P. stenostachys stands. The highest N:P ratios were also found in the littoral region. Carbon stable isotopic analysis (δ13C signatures showed that a majority of the particulate organic carbon (POC in the water column had aquatic macrophyte tissues origin; CONCLUSIONS: Emergent macrophytes strongly contribute to nutrient enrichment of the sediment of Cabiúnas lagoon. In general, macrophyte detritus alters the littoral region sediment stoichiometry and quality for decomposers, by accumulating much more C in relation to N and P when compared to limnetic region. However, macrophytes importance isn't restricted to the sediment once they have a central

  13. Delivery of suspended sediment and associated phosphorus and heavy metals to small rural Danish streams

    Laubel, A. R.

    The aim of this study is to examine delivery pathways for suspended sediment, and particulate phosphorus (P) and heavy metals from open rural areas to small Danish streams. A further aim is to quantify the contribution from different path-ways and source areas. Such studies are useful as a basis...

  14. Suspended graphene variable capacitor

    AbdelGhany, M.; Mahvash, F.; Mukhopadhyay, M.; Favron, A.; Martel, R.; Siaj, M.; Szkopek, T.


    Electromechanical variable capacitors, or varactors, find a wide range of applications including sensing applications and the tuning of electrical circuit resonance. We demonstrate a nano-electromechanical graphene varactor, a variable capacitor wherein the capacitance is tuned by voltage controlled deflection of a dense array of suspended graphene membranes. The low flexural rigidity of graphene monolayers is exploited to achieve low actuation voltage and high tunable capacitance density in an ultra-thin structure. Large arrays comprising thousands of suspensions were fabricated to give a tunable capacitance of over 10 pF mm-2. This capacitance density suggests that graphene offers a potential solution to the challenge of reducing the size of micro-electromechanical systems (MEMS). A capacitance tuning of 55% was achieved with a 10 V actuating voltage, exceeding the 50% tuning limit of Hookean parallel plate pull-in without the use of complex mechanical schemes that occupy substrate area. Capacitor behavior was investigated experimentally, and described by a simple theoretical model. Mechanical properties of the graphene membranes were measured independently using atomic force microscopy. We present a comparison of state-of-the-art MEMS and graphene varactors. The quality factor of graphene varactors is limited by graphene sheet resistance, pull-in voltage can be improved with more aggressive scaling, while the power handling and cycling stability of graphene varactors remains unknown.


    Barron, E. S. Guzman; Nelson, Leonard; Ardao, Maria Isabel


    Oxidizing agents of sulfhydryl groups such as iodosobenzoate, alkylating agents such as iodoacetamide, and mercaptide-forming agents such as cadmium chloride, mercuric chloride, p-chloromercuribenzoate, sodium arsenite, and p-carboxyphenylarsine oxide, added in small concentrations to a suspension of sea urchin sperm produced an increase in respiration. When the concentration was increased there was an inhibition. These effects are explained by postulating the presence in the cells of two kinds of sulfhydryl groups: soluble sulfhydryl groups, which regulate cellular respiration, and fixed sulfhydryl groups, present in the protein moiety of enzymes. Small concentrations of sulfhydryl reagents combine only with the first, thus producing an increase in respiration; when the concentration is increased, the fixed sulfhydryl groups are also attacked and inhibition of respiration is the consequence. Other inhibitors of cell respiration, such as cyanide and urethanes, which do not combine with —SH groups, did not stimulate respiration in small concentration. PMID:18891144

  16. Respiration in ocean margin sediments

    Andersson, J.H.


    The aim of this thesis was the study of respiration in ocean margin sediments and the assessments of tools needed for this purpose. The first study was on the biological pump and global respiration patterns in the deep ocean using an empirical model based on sediment oxygen consumption data. In this thesis the depth dependence of respiration patterns was modelled using a compiled data set of sediment oxygen consumption rates. We showed that the depth relationship can best be described by a do...

  17. Ecotoxic impact of suspended solids collected from polluted surface waters

    Weltens, R.; Witters, H.; Corbisier, P. [Vito, Environmental Toxicology, MOL (Belgium)


    Scope and background. Earlier studies showed that artificially contaminated particulate matter could be responsible for acute effects in water fleas and fish. Physical/chemical measurements on suspended solids and river water collected in the field showed that these samples were often contaminated with mixtures of toxic molecules. Objectives. The present pilot study was started to investigate the possible ecotoxic impact of suspended solids collected in situ. Methods. Suspended solids and river waters were collected from 22 locations of polluted rivers in the Flanders. An extensive list of chemical components and physical parameters were measured in these matrices. Partition coefficients for water column and suspended solids were calculated. Toxicity of suspensions of solid materials was investigated in 3 test organisms of different trophic levels: Bacteria (BIOMET trademark), filter feeder (Daphnia magna) and fish (rainbow trout (Oncorhynchus mykiss) or zebrafish (Danio rerio)). The acute toxicity was measured in a worst-case scenario using high concentrations of solids resuspended in standard medium and at standard conditions. (orig.)


    Kevin C. Galbreath; Charlene R. Crocker; Carolyn M. Nyberg; Frank E. Huggins; Gerald P. Huffman


    A four-step sequential Ni extraction method, summarized in Table AB-1, was evaluated for identifying and quantifying the Ni species occurring in urban total suspended particulate (TSP) matter and fine particulate matter (<10 {micro}m [PM{sub 10}] and <2.5 {micro}m [PM{sub 2.5}] in aerodynamic diameter). The extraction method was originally developed for quantifying soluble, sulfidic, elemental, and oxidic forms of Ni that may occur in industrial atmospheres. X-ray diffraction (XRD) and x-ray absorption fine structure (XAFS) spectroscopy were used to evaluate the Ni species selectivity of the extraction method. Uncertainties in the chemical speciation of Ni in urban PM{sub 10} and PM{sub 2.5} greatly affect inhalation health risk estimates, primarily because of the large variability in acute, chronic, and cancer-causing effects for different Ni compounds.

  19. Respiration in ocean margin sediments

    Andersson, J.H.


    The aim of this thesis was the study of respiration in ocean margin sediments and the assessments of tools needed for this purpose. The first study was on the biological pump and global respiration patterns in the deep ocean using an empirical model based on sediment oxygen consumption data. In this

  20. Respiration in ocean margin sediments

    Andersson, J.H.


    The aim of this thesis was the study of respiration in ocean margin sediments and the assessments of tools needed for this purpose. The first study was on the biological pump and global respiration patterns in the deep ocean using an empirical model based on sediment oxygen consumption data.

  1. Light respiration in Chlorella sorokiniana

    Kliphuis, A.M.J.; Janssen, M.G.J.; End, van den E.J.; Martens, D.E.; Wijffels, R.H.


    Respiration and photosynthesis are two important processes in microalgal growth that occur simultaneously in the light. To know the rates of both processes, at least one of them has to be measured. To be able to measure the rate of light respiration of Chlorella sorokiniana, the measurement of oxyge

  2. [Variation of nitrogen during the high suspended sediments concentration water supply in an artificial shallow lake].

    Chen, You-yuan; Shen, Yu; Yang, Shi-ying


    The effect of water quality and suspended sediments in the process of water supply is of an increasing concern recently in an artificial shallow lake. The water supply from the Yellow River to Dongchang Lake happened on April 23rd to 25th, 2012. The synchronous monitoring of flow velocity, suspended sediment concentration, dissolved nitrogen and particulate nitrogen concentration was conducted during the three days in five monitoring sites of the longitudinal profile from inlet to outlet. The spatio-temporal variation of nitrogen and the relationship between nitrogen concentration and suspended sediment concentration was analyzed. Moreover, the analysis of different nitrogen forms in surface water and bottom sediment was also made in the whole lake before and after the water supply. Results showed that the process of water supplement had an obvious effect on flow velocities and suspended sediment concentrations around the inlet area. The influence area was a limited scope. The spatial distribution of nitrogen presented a certain concentration gradient along the flow direction. Around the water inlet, concentrations of all nitrogen forms in water and bottom sediment was higher than those in other lake zones. The amplitude of variation of all nitrogen concentrations in surface water, suspended sediments showed a decreasing trend from water inlet to outlet. And concentrations of total dissolved and particulate nitrogen increased at different ratios after water supply in the lake. Total particulate nitrogen concentration increase was higher. It revealed the water supply of the Yellow River had a great influence on lake water. The dissolved nitrogen was the main nitrogen form in water supply. The ratio of total dissolved nitrogen to particulate nitrogen was 7.3 : 1. Nitrate was the primary form in dissolved nitrogen, and ammonium was the primary form in particulate nitrogen, respectively. The correlation between concentration of suspended sediments and ammonium, total

  3. Cooling of suspended nanostructures with tunnel junctions

    Koppinen, P. J.; Maasilta, I. J.


    We have investigated electronic cooling of suspended nanowires with SINIS tunnel junction coolers. The suspended samples consist of a free standing nanowire suspended by four narrow ($\\sim$ 200 nm) bridges. We have compared two different cooler designs for cooling the suspended nanowire. We demonstrate that cooling of the nanowire is possible with a proper SINIS cooler design.

  4. Analysis of suspended solids by single-particle scattering. [for Lake Superior pollution monitoring

    Diehl, S. R.; Smith, D. T.; Sydor, M.


    Light scattering by individual particulates is used in a multiple-detector system to categorize the composition of suspended solids in terms of broad particulate categories. The scattering signatures of red clay and taconite tailings, the two primary particulate contaminants in western Lake Superior, along with two types of asbestiform fibers, amphibole and chrysolite, were studied in detail. A method was developed to predict the concentration of asbestiform fibers in filtration plant samples for which electron microscope analysis was done concurrently. Fiber levels as low as 50,000 fibers/liter were optically detectable. The method has application in optical categorization of samples for remote sensing purposes and offers a fast, inexpensive means for analyzing water samples from filtration plants for specific particulate contaminants.

  5. Respiration in spiders (Araneae).

    Schmitz, Anke


    Spiders (Araneae) are unique regarding their respiratory system: they are the only animal group that breathe simultaneously with lungs and tracheae. Looking at the physiology of respiration the existence of tracheae plays an important role in spiders with a well-developed tracheal system. Other factors as sex, life time, type of prey capture and the high ability to gain energy anaerobically influence the resting and the active metabolic rate intensely. Most spiders have metabolic rates that are much lower than expected from body mass; but especially those with two pairs of lungs. Males normally have higher resting rates than females; spiders that are less evolved and possess a cribellum have lower metabolic rates than higher evolved species. Freely hunting spiders show a higher energy turnover than spiders hunting with a web. Spiders that live longer than 1 year will have lower metabolic rates than those species that die after 1 year in which development and reproduction must be completed. Lower temperatures and starvation, which most spiders can cope with, will decrease the metabolic rate as well.

  6. From breathing to respiration.

    Fitting, Jean-William


    The purpose of breathing remained an enigma for a long time. The Hippocratic school described breathing patterns but did not associate breathing with the lungs. Empedocles and Plato postulated that breathing was linked to the passage of air through pores of the skin. This was refuted by Aristotle who believed that the role of breathing was to cool the heart. In Alexandria, breakthroughs were accomplished in the anatomy and physiology of the respiratory system. Later, Galen proposed an accurate description of the respiratory muscles and the mechanics of breathing. However, his heart-lung model was hampered by the traditional view of two non-communicating vascular systems - veins and arteries. After a period of stagnation in the Middle Ages, knowledge progressed with the discovery of pulmonary circulation. The comprehension of the purpose of breathing progressed by steps thanks to Boyle and Mayow among others, and culminated with the contribution of Priestley and the discovery of oxygen by Lavoisier. Only then was breathing recognized as fulfilling the purpose of respiration, or gas exchange. A century later, a controversy emerged concerning the active or passive transfer of oxygen from alveoli to the blood. August and Marie Krogh settled the dispute, showing that passive diffusion was sufficient to meet the oxygen needs.

  7. Geospatial approach towards enumerative analysis of suspended sediment concentration for Ganges-Brahmaputra Bay

    Pandey, Palak; Kunte, Pravin D.


    This study presents an easy, modular, user-friendly, and flexible software package for processing of Landsat 7 ETM and Landsat 8 OLI-TIRS data for estimating suspended particulate matter concentrations in the coastal waters. This package includes 1) algorithm developed using freely downloadable SCILAB package, 2) ERDAS Models for iterative processing of Landsat images and 3) ArcMAP tool for plotting and map making. Utilizing SCILAB package, a module is written for geometric corrections, radiometric corrections and obtaining normalized water-leaving reflectance by incorporating Landsat 8 OLI-TIRS and Landsat 7 ETM+ data. Using ERDAS models, a sequence of modules are developed for iterative processing of Landsat images and estimating suspended particulate matter concentrations. Processed images are used for preparing suspended sediment concentration maps. The applicability of this software package is demonstrated by estimating and plotting seasonal suspended sediment concentration maps off the Bengal delta. The software is flexible enough to accommodate other remotely sensed data like Ocean Color monitor (OCM) data, Indian Remote Sensing data (IRS), MODIS data etc. by replacing a few parameters in the algorithm, for estimating suspended sediment concentration in coastal waters.

  8. Geospatial approach towards enumerative analysis of suspended sediment concentration for Ganges-Brahmaputra Bay

    Pandey, P.; Kunte, P.D.

    stream_size 47513 stream_content_type text/plain stream_name Comput_Geosci_95_32a.pdf.txt stream_source_info Comput_Geosci_95_32a.pdf.txt Content-Encoding UTF-8 Content-Type text/plain; charset=UTF-8 1    Author Version...-dominated coastal waters, sophisticated algorithms are mainly needed to estimate accurately the suspended particulate concentrations from remotely sensed ocean color data (Robinson et al., 1998; Moore et al., 1999). Suspended sediment transport is a continuous...

  9. 29 CFR 1471.1010 - Suspending official.


    ... 29 Labor 4 2010-07-01 2010-07-01 false Suspending official. 1471.1010 Section 1471.1010 Labor Regulations Relating to Labor (Continued) FEDERAL MEDIATION AND CONCILIATION SERVICE GOVERNMENTWIDE DEBARMENT AND SUSPENSION (NONPROCUREMENT) Definitions § 1471.1010 Suspending official. (a) Suspending...

  10. 2 CFR 180.1010 - Suspending official.


    ... 2 Grants and Agreements 1 2010-01-01 2010-01-01 false Suspending official. 180.1010 Section 180.1010 Grants and Agreements OFFICE OF MANAGEMENT AND BUDGET GOVERNMENTWIDE GUIDANCE FOR GRANTS AND...) Definitions § 180.1010 Suspending official. (a) Suspending official means an agency official who is...

  11. 29 CFR 98.1010 - Suspending official.


    ... 29 Labor 1 2010-07-01 2010-07-01 true Suspending official. 98.1010 Section 98.1010 Labor Office of the Secretary of Labor GOVERNMENTWIDE DEBARMENT AND SUSPENSION (NONPROCUREMENT) Definitions § 98.1010 Suspending official. (a) Suspending official means an agency official who is authorized to impose...

  12. 22 CFR 208.1010 - Suspending official.


    ... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Suspending official. 208.1010 Section 208.1010 Foreign Relations AGENCY FOR INTERNATIONAL DEVELOPMENT GOVERNMENTWIDE DEBARMENT AND SUSPENSION (NONPROCUREMENT) Definitions § 208.1010 Suspending official. (a) Suspending official means an agency official...

  13. 21 CFR 1404.1010 - Suspending official.


    ... 21 Food and Drugs 9 2010-04-01 2010-04-01 false Suspending official. 1404.1010 Section 1404.1010 Food and Drugs OFFICE OF NATIONAL DRUG CONTROL POLICY GOVERNMENTWIDE DEBARMENT AND SUSPENSION (NONPROCUREMENT) Definitions § 1404.1010 Suspending official. (a) Suspending official means an agency official...

  14. 31 CFR 19.1010 - Suspending official.


    ... 31 Money and Finance: Treasury 1 2010-07-01 2010-07-01 false Suspending official. 19.1010 Section 19.1010 Money and Finance: Treasury Office of the Secretary of the Treasury GOVERNMENTWIDE DEBARMENT AND SUSPENSION (NONPROCUREMENT) Definitions § 19.1010 Suspending official. (a) Suspending...

  15. 34 CFR 85.1010 - Suspending official.


    ... designated by the agency head. (b) Authority: E.O. 12549 (3 CFR, 1986 Comp., p. 189); E.O 12689 (3 CFR, 1989... 34 Education 1 2010-07-01 2010-07-01 false Suspending official. 85.1010 Section 85.1010 Education...) Definitions § 85.1010 Suspending official. (a) Suspending official means an agency official who is...

  16. Method and apparatus for injecting particulate media into the ground

    Dwyer, Brian P.; Dwyer, Stephen F.; Vigil, Francine S.; Stewart, Willis E.


    An improved method and apparatus for injecting particulate media into the ground for constructing underground permeable reactive barriers, which are used for environmental remediation of subsurface contaminated soil and water. A media injector sub-assembly attached to a triple wall drill string pipe sprays a mixture of active particulate media suspended in a carrier fluid radially outwards from the sub-assembly, at the same time that a mixing fluid is sprayed radially outwards. The media spray intersects the mixing spray at a relatively close distance from the point of injection, which entrains the particulate media into the mixing spray and ensures a uniform and deep dispersion of the active media in the surrounding soil. The media injector sub-assembly can optionally include channels for supplying compressed air to an attached down-the-hole hammer drive assembly for use during drilling.

  17. Dry release of suspended nanostructures

    Forsén, Esko Sebastian; Davis, Zachary James; Dong, M.;


    A dry release method for fabrication of suspended nanostructures is presented. The technique has been combined with an anti-stiction treatment for fabrication of nanocantilever based nanoelectromechanical systems (NEMS). The process combines a dry release method, using a supporting layer of photo......A dry release method for fabrication of suspended nanostructures is presented. The technique has been combined with an anti-stiction treatment for fabrication of nanocantilever based nanoelectromechanical systems (NEMS). The process combines a dry release method, using a supporting layer......, the technique enables long time storage and transportation of produced devices without the risk of stiction. By combining the dry release method with a plasma deposited anti-stiction coating both fabrication induced stiction, which is mainly caused by capillary forces originating from the dehydration...

  18. A First Evaluation of LANDSAT TM Data to Monitor Suspended Sediments in Lakes. [Lake Chicot, Arkansas

    Schiebe, F. R.; Ritchie, J. C.; Boatwright, G. O.


    The use of LANDSAT to monitor and track changes in the water quality of Lake Chicot, Arizona was assessed using MSS and TM digital data from nine water sites. Results show that: (1) TM Bands 1, 2, 3, and 4 appear to be providing information on concentrations of particulate matter suspended in surface waters. These bands are also highly interrelated for water samples; (2) preliminary evaluation indicates that TM Band 3 showed the best relationship to surface suspended solids; (3) TM Bands 5 and 7 are useful for separating water from nonwater areas; (4) the MSS Bands 2 and 3 can be related to suspended solids in surface water, as has already been shown from previous LANDSAT research; and (5) analysis of TM Band 6 indicates that while synoptic temperature patterns may be discerned, the digital sensitivity to a two degree temperature difference is low.

  19. Comparison of continuous monitor (TEOM) and gravimetric sampler particulate matter concentrations

    The Tapered Element Oscillating Microbalance (TEOM) sampler is an EPA designated equivalent method sampler for measuring PM10 concentrations. PM10 refers to the mass fraction of particulate matter suspended in the atmosphere having a nominal aerodynamic diameter less than or equal to 10 micrometers ...

  20. Trends and the effect of management on macronutrients in fractionated particulate matter in rooster house

    The persistence and long life expectancy of ammonia, odors and toxic pollutants from poultry houses may be due to the ability of suspended particulate matters (SPM) to serve as carriers for odorous compounds such as ammonium ions and volatile organic compounds. SPM is generated from the feed, anima...

  1. General Instructions for Disposable Respirators


    This podcast, intended for the general public, demonstrates how to put on and take off disposable respirators that are to be used in areas affected by the influenza outbreak.  Created: 4/9/2009 by CDC, National Institute for Occupational Safety and Health (NIOSH).   Date Released: 4/29/2009.

  2. Use of Facemasks and Respirators


    This program demonstrates the differences of facemasks and respirators that are to be used in public settings during an influenza pandemic.  Created: 5/15/2007 by CDC, National Institute for Occupational Safety and Health (NIOSH).   Date Released: 5/25/2007.

  3. Emission characters of particulate concentrations and dry deposition studies for incense burning at a Taiwanese temple.

    Fang, Guor-Cheng; Chu, Chia-Chium; Wu, Yuh-Shen; Fu, Peter Pi-Cheng


    Suspended particulate concentrations were measured at the Tzu Yun Yen temple in the Taichung region of Taiwan. The temple performs traditional incense burning. A universal sampler and a micro-orifice uniform deposited impactor (MOUDI) sampler with a dry deposition plate were used to measure the particulate concentrations. The results show that the average PM2.5/PM10 ratio was 74% during the incense burning period at this temple. In addition, the average suspended particulate (PM10) element concentration of anthropogenic element Zn (495 ng/m3) was higher than the other anthropogenic elements (Pb, Mn, Ni, and Cd). Furthermore, the average mass size distribution was bimodal with major peaks occurring at 0.32-0.56 microm and 5.6-10 microm during the incense burning period. The dry deposition velocities of Cd used fine particulates (PM2.5) and suspended particulate (PM10) mode were 1.86 and 0.99 cm/s in this study, respectively.

  4. Soil Respiration: Concept and Measurement Methods



    Full Text Available Soil respiration is the main element in the carbon cycle that makes possible for plants carbon plants to return inthe atmosphere. The objective of this work was to present and discuss some aspects of the soil CO2 efflux. We definedherein, some terms associated to the soil respiration concept, we tackled some aspects regarding the influence oftemperature, humidity and soil pH on soil respiration and we presented the principle of soil respiration measurement byusing dynamic closed chamber system.

  5. The Midbrain Periaqueductal Gray Control of Respiration

    Subramanian, Hari H.; Balnave, Ron J.; Holstege, Gert


    The midbrain periaqueductal gray (PAG) organizes basic survival behavior, which includes respiration. How the PAG controls respiration is not known. We studied the PAG control of respiration by injecting D,L-homocysteic acid in the PAG in unanesthetized precollicularly decerebrated cats. Injections

  6. Distribution of particulate carbohydrate species in the Bay of Bengal

    Vishwas B Khodse; Narayan B Bhosle; V V Gopalkrishna


    Suspended particulate matter (SPM)of surface seawaters was collected during December 2003 to October 2004 at 10 stations in the Bay of Bengal,and analyzed for particulate organic carbon (POC),total particulate nitrogen (TPN),total particulate carbohydrate (TPCHO)and total particulate uronic acids (TPURA).The concentrations of POC,TPCHO and TPURA varied from 4.80 to 29.12,0.85 to 4.24,0.09 to 0.91 C,respectively.The TPCHO-C and TPURA-C accounted for 6.6 –32.5%and 0.87 –3.65%of POC.The trends observed for the distribution of these compounds were generally similar to those recorded for the distribution of chlorophyll (Chl ) .The C/N ratios varied from 3.2 to 22.3 with most of the values being > 10.This suggests that the organic matter was mostly derived from phytoplankton and bacteria.Relatively low C/N ratios and high TPCHO yield imply that freshly derived organic matter was present during SWM and FIM.Our data suggest that the quality and quantity of organic matter varied spatially and seasonally.

  7. Univers de Particules

    CERN Video Productions


    Dans l’Univers, tout est fait de particules. Mais d’où viennent-elles? Quelle est l’origine des lois de la nature? Au rez-de-chaussée du Globe de la science et de l’innovation, l’exposition permanente « Univers de particules » vous invite à un voyage vers le Big Bang en explorant le CERN. Avec à la clé des réponses aux questions: pourquoi cette recherche ? Comment accélérer des particules ? Comment les détecter ? Quelles sont les théories sur la matière et sur l’Univers aujourd’hui ? Quelles retombées pour notre vie quotidienne ?


    H. Asilian, M. Nasseri Nejad, S. B. Mortazavi, M. J. Jafari, A. Khavanin, A. R. Dehdashti


    Full Text Available Dust consists of tiny solid particles carried by air currents. These particles are formed by many different processes. One of these processes is polymerization of inert plastic such as Polyvinyl Chloride production plant. According to the Occupational Health and Safety Assessment Series requirements, section 4.4.6, occupational health and safety risks must be defined and controlled where needed. This field study was conducted to evaluate the occupational exposure of packaging operators to airborne polyvinyl chloride dust in order to health risk assessment and recommend feasible controlling methods. The mass concentration of polyvinyl chloride particulate was measured in two fractions according to the particle size that expressed as total and respirable particulates. The Air Sampling Methods, Methods for the Determination of Hazardous Substances 14/3, of Health and Safety Executive were used as a standard sampling protocol. The average mass concentrations for respirable and total particulates were measured 3.54±0.3 mg/m3 and 11.89±0.8 mg/m3 respectively. Also health risks of studied condition were estimated as significant level, category one, therefore the risk must be reduced below the standard level. According to the work requirements to reduce the emission rate and mitigate the health risk exposure, a local exhaust ventilation system design was recommended for bag-filters of hopper tank.

  9. Microwave regenerated particulate trap

    McDonald, A.C. Jr.; Yonushonis, T.M. [Cummins Engine Co., Inc., Columbus, IN (United States); Haberkamp, W.C.; Mako, F.; Len, L.K,; Silberglitt, R.; Ahmed, I. [FM Technologies, Inc., Fairfax, VA (United States)


    It has been demonstrated that a fibrous particulate filter can extract particulate matter from the diesel exhaust. However, additional engineering efforts remains to achieve the design target of 90%. It has also be shown that with minor modifications magnetrons produced for home ovens can endure a simulated diesel operating environment. Much work remains to develop a robust product ready to complete extensive engine testing and evaluation. These efforts include: (1) additional environmental testing of magnetrons; (2) vibration testing of the filter in the housing; (3) evaluating alternative methods/designs to seal the center bore; and (4) determining the optimum coating thickness that provides sufficient structural integrity while maintaining rapid heating rates.

  10. Evaluation of city buses installed diesel particulate filter systems on fleet test; Diesel particulate filter system wo tosaishita rosen bus no soko chosa

    Sudo, H. [Japan Automobile Research Institute Inc., Tsukuba (Japan)


    An environmental air quality of suspended particulate matter is insufficient in the big city area. To reduce the particulate matter, improvement of engine and development of the Diesel Particulate Filter (DPF) system are carrying. The purpose of this report is to investigate a possibility of practical use of the city buses installed DPF systems. From March 1995, investigation for practical use of these DPF systems on a route buses was carried in regular service operation of the Tokyo and Yokohama Transportation Bureau. The investigation items are service situation, smoke density and preparation inspection. From the result for 2 years service operation, each DPF systems needed some failure correspondence. but these were not fatal problem on using the DPF system. Then the subject of relative to durability and reliability became clear, and the performance of a low particulate emission DPF system obtained the high value evaluation for users. 9 refs., 4 figs., 2 tabs.

  11. Chemical and physical characteristics of cellulose insulation particulates, and evaluation of potential acute pulmonary toxicity.

    Morgan, Daniel L; Su, Yin-Fong; Dill, Jeffrey A; Turnier, John C; Westerberg, R Bruce; Smith, Cynthia S


    During installation of cellulose insulation (CI) in new and older houses, significant quantities of airborne material are generated. This study characterized the chemical and physical properties, and potential acute pulmonary toxicity of CI. CI from four manufacturers was analyzed for inorganic additives and trace element impurities. Aerosols were generated and size fractionated. The number and size of fibrous and nonfibrous particles in the respirable fractions were determined. Respirable CI particulates were intratracheally instilled in rats (5 mg/kg) to evaluate potential pulmonary toxicity. CI samples were similar in composition with small differences due primarily to fire retardants. Less than 0.1% of CI was respirable and contained few fibers. Acute exposure to CI caused transient inflammation in the lungs and increased 4-hydroxyproline. Microscopic evaluation revealed a minimal to mild, non-progressing granulomatous pneumonitis. Low concentrations of respirable particles were found in CI aerosols. Particles consisted primarily of fire retardants with few fibers, and caused mild pulmonary toxicity in rats.

  12. Mesoporous silica nanoparticles inhibit cellular respiration.

    Tao, Zhimin; Morrow, Matthew P; Asefa, Tewodros; Sharma, Krishna K; Duncan, Cole; Anan, Abhishek; Penefsky, Harvey S; Goodisman, Jerry; Souid, Abdul-Kader


    We studied the effect of two types of mesoporous silica nanoparticles, MCM-41 and SBA-15, on mitochondrial O 2 consumption (respiration) in HL-60 (myeloid) cells, Jurkat (lymphoid) cells, and isolated mitochondria. SBA-15 inhibited cellular respiration at 25-500 microg/mL; the inhibition was concentration-dependent and time-dependent. The cellular ATP profile paralleled that of respiration. MCM-41 had no noticeable effect on respiration rate. In cells depleted of metabolic fuels, 50 microg/mL SBA-15 delayed the onset of glucose-supported respiration by 12 min and 200 microg/mL SBA-15 by 34 min; MCM-41 also delayed the onset of glucose-supported respiration. Neither SBA-15 nor MCM-41 affected cellular glutathione. Both nanoparticles inhibited respiration of isolated mitochondria and submitochondrial particles.

  13. Plastron Respiration Using Commercial Fabrics


    A variety of insect and arachnid species are able to remain submerged in water indefinitely using plastron respiration. A plastron is a surface-retained film of air produced by surface morphology that acts as an oxygen-carbon dioxide exchange surface. Many highly water repellent and hydrophobic surfaces when placed in water exhibit a silvery sheen which is characteristic of a plastron. In this article, the hydrophobicity of a range of commercially available water repellent fabrics and polymer...

  14. Particulate Matter (PM) Pollution

    ... affect the heart and lungs and cause serious health effects. December 1, 2016 - EPA proposes air quality determinations for eleven areas designated "nonattainment" for the 24-hour fine particle standards. Particulate Matter (PM) Pollution PM Basics What is PM, and how does ...

  15. Modeling of Particulate Emissions


    Particulates • SOx Cloud Formation Global Warming * - Greenhouse Gases Ozone Layer Depletion - Not an Immediate Concern Global Warming - An Emerging...Concern Local Air Quality - A Continuing Concern Ground Level Troposphere Ozone Layer Depletion • H2O Ozone Depletion (ice formation) 5 Modeling

  16. Instructions for Sampling Particulates.

    Ekman, Frank

    This technical report presents detailed instructions for sampling particulates. The table of contents includes sections on Introduction, Volume Determinations, Apparatus - Assembly and Operation, Sampling Techniques, and Acknowledgment. Six charts, 24 graphs, and one diagram are appended to facilitate sampling, as well as sections on Isokinetic…

  17. 5 CFR 919.1010 - Suspending official.


    ... 5 Administrative Personnel 2 2010-01-01 2010-01-01 false Suspending official. 919.1010 Section 919.1010 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) GOVERNMENTWIDE DEBARMENT AND SUSPENSION (NONPROCUREMENT) Definitions § 919.1010 Suspending...

  18. A comparison of facemask and respirator filtration test methods.

    Rengasamy, Samy; Shaffer, Ronald; Williams, Brandon; Smit, Sarah


    NIOSH published a Federal Register Notice to explore the possibility of incorporating FDA required filtration tests for surgical masks (SMs) in the 42 CFR Part 84 respirator certification process. There have been no published studies comparing the filtration efficiency test methods used for NIOSH certification of N95 filtering facepiece respirators (N95 FFRs) with those used by the FDA for clearance of SMs. To address this issue, filtration efficiencies of "N95 FFRs" including six N95 FFR models and three surgical N95 FFR models, and three SM models were measured using the NIOSH NaCl aerosol test method, and FDA required particulate filtration efficiency (PFE) and bacterial filtration efficiency (BFE) methods, and viral filtration efficiency (VFE) method. Five samples of each model were tested using each method. Both PFE and BFE tests were done using unneutralized particles as per FDA guidance document. PFE was measured using 0.1 µm size polystyrene latex particles and BFE with ∼3.0 µm size particles containing Staphylococcus aureus bacteria. VFE was obtained using ∼3.0 µm size particles containing phiX 174 as the challenge virus and Escherichia coli as the host. Results showed that the efficiencies measured by the NIOSH NaCl method for "N95 FFRs" were from 98.15-99.68% compared to 99.74-99.99% for PFE, 99.62-99.9% for BFE, and 99.8-99.9% for VFE methods. Efficiencies by the NIOSH NaCl method were significantly (p = PFE, BFE, and VFE methods produced no significant difference. The above results show that the NIOSH NaCl method is relatively conservative and is able to identify poorly performing filtration devices. The higher efficiencies obtained using PFE, BFE and VFE methods show that adding these supplemental particle penetration methods will not improve respirator certification.

  19. Interaction between ozone and airborne particulate matter in office air

    Mølhave, Lars; Kjærgaard, Søren K.; Sigsgaard, Torben


    This study investigated the hypotheses that humans are affected by air pollution caused by ozone and house dust, that the effect of simultaneous exposure to ozone and dust in the air is larger than the effect of these two pollutants individually, and that the effects can be measured as release...... of cytokines and changes of the respiratory function. Experimental exposures of eight atopic but otherwise healthy subjects were performed in a climate chamber under controlled conditions. The three controlled exposures were about 75 microg/m3 total suspended particulate matter, 0.3 p.p.m. ozone...

  20. Particulate matter dynamics

    Cionco, Rodolfo G; Caligaris, Marta G


    A substantial fraction of the particulate matter released into the atmosphere by industrial or natural processes corresponds to particles whose aerodynamic diameters are greater than 50 mm. It has been shown that, for these particles, the classical description of Gaussian plume diffusion processes, is inadequate to describe the transport and deposition. In this paper we present new results concerning the dispersion of coarse particulate matter. The simulations are done with our own code that uses the Bulirsch Stoer numerical integrator to calculate threedimensional trajectories of particles released into the environment under very general conditions. Turbulent processes are simulated by the Langevin equation and weather conditions are modeled after stable (Monin-Obukhov length L> 0) and unstable conditions (L <0). We present several case studies based on Monte Carlo simulations and discusses the effect of weather on the final deposition of these particles.

  1. Air emission in France. Metropolitan area particulate matter; Emissions dans l'air en France. Metropole poussieres



    Substances and index currently in survey are: Particulate matter: Total suspended particulates (TSP), Fine particulates with an equivalent aerodynamic diameter less than 10 {mu}m (PM{sub 10}), 2.5 {mu}m (PM{sub 2.5}) and 1.0 {mu}m (PM{sub 1.0}). Density ratios relating to population, area, gross product, primary energy consumption, etc. Annual emissions are provided for each substance since 1990. Dates corresponding to the maximum and minimum values are also included. Results are provisional for 2001. (author)

  2. Respirators: Supervisors Self-Study #43442

    Chochoms, Michael [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)


    This course, Respirators: Supervisors Self-Study (#43442), addresses training requirements for supervisors of respirator wearers as specified by the American National Standard Institute (ANSI) Standard for Respiratory Protection, ANSI Z88.2, and as incorporated by reference in the Department of Energy (DOE) Worker Health and Safety Rule, 10 Code of Federal Regulations (CFR) 851. This course also presents the responsibilities of supervisors of respirator wearers at Los Alamos National Laboratory (LANL).


    Stanley J. Miller; Grant L. Schelkoph; Grant E. Dunham


    A new concept in particulate control, called an advanced hybrid particulate collector (AHPC), is being developed under funding from the US Department of Energy. The AHPC combines the best features of electrostatic precipitators (ESPs) and baghouses in an entirely novel manner. The AHPC concept combines fabric filtration and electrostatic precipitation in the same housing, providing major synergism between the two methods, both in the particulate collection step and in transfer of dust to the hopper. The AHPC provides ultrahigh collection efficiency, overcoming the problem of excessive fine-particle emissions with conventional ESPs, and solves the problem of reentrainment and recollection of dust in conventional baghouses. Phase I of the development effort consisted of design, construction, and testing of a 5.7-m{sup 3}/min (200-acfm) working AHPC model. Results from both 8-hour parametric tests and 100-hour proof-of-concept tests with two different coals demonstrated excellent operability and greater than 99.99% fine-particle collection efficiency.

  4. Photosynthesis, respiration, and carbon turnover in sinking marine snow from surface waters of Southern California Bight: implications for the carbon cycle in the ocean

    Ploug, H.; Grossart, HP; Azam, F.


    aggregate in darkness, which yielded a turnover time of 8 to 9 d for the total organic carbon in aggregates. Thus, marine snow is not only a vehicle for vertical flux of organic matter; the aggregates are also hotspots of microbial respiration which cause a fast and efficient respiratory turnover...... of particulate organic carbon in the sea....

  5. Plastron Respiration Using Commercial Fabrics

    Shaun Atherton


    Full Text Available A variety of insect and arachnid species are able to remain submerged in water indefinitely using plastron respiration. A plastron is a surface-retained film of air produced by surface morphology that acts as an oxygen-carbon dioxide exchange surface. Many highly water repellent and hydrophobic surfaces when placed in water exhibit a silvery sheen which is characteristic of a plastron. In this article, the hydrophobicity of a range of commercially available water repellent fabrics and polymer membranes is investigated, and how the surface of the materials mimics this mechanism of underwater respiration is demonstrated allowing direct extraction of oxygen from oxygenated water. The coverage of the surface with the plastron air layer was measured using confocal microscopy. A zinc/oxygen cell is used to consume oxygen within containers constructed from the different membranes, and the oxygen consumed by the cell is compared to the change in oxygen concentration as measured by an oxygen probe. By comparing the membranes to an air-tight reference sample, it was found that the membranes facilitated oxygen transfer from the water into the container, with the most successful membrane showing a 1.90:1 ratio between the cell oxygen consumption and the change in concentration within the container.


    The sources of heavy metals in urban stormwater runoff are diverse (e.g., highways, road surfaces, roofs) and the release of metals into the environment is governed by several complex mechanisms. Heavy metals in stormwater are associated with suspended particulate materials that ...

  7. 42 CFR 84.197 - Respirator containers; minimum requirements.


    ... 42 Public Health 1 2010-10-01 2010-10-01 false Respirator containers; minimum requirements. 84.197... Cartridge Respirators § 84.197 Respirator containers; minimum requirements. Respirators shall be equipped... commercial designation of the respirator it contains and all appropriate approval labels....

  8. 42 CFR 84.134 - Respirator containers; minimum requirements.


    ... 42 Public Health 1 2010-10-01 2010-10-01 false Respirator containers; minimum requirements. 84.134... Respirators § 84.134 Respirator containers; minimum requirements. Supplied-air respirators shall be equipped... commercial designation of the respirator it contains, and all appropriate approval labels....

  9. 42 CFR 84.190 - Chemical cartridge respirators: description.


    ... 42 Public Health 1 2010-10-01 2010-10-01 false Chemical cartridge respirators: description. 84.190... Cartridge Respirators § 84.190 Chemical cartridge respirators: description. (a) Chemical cartridge respirators including all completely assembled respirators which are designed for use as...

  10. 42 CFR 84.130 - Supplied-air respirators; description.


    ... 42 Public Health 1 2010-10-01 2010-10-01 false Supplied-air respirators; description. 84.130... Respirators § 84.130 Supplied-air respirators; description. Supplied-air respirators, including all completely assembled respirators designed for use as respiratory protection during entry into and escape...

  11. Pyrogenic effect of respirable road dust particles

    Jayawardena, Umesh; Tollemark, Linda; Tagesson, Christer; Leanderson, Per, E-mail: per.leanderson@lio.s [Occupational and Environmental Medicine, University Hospital, S-581 85 Linkoeping (Sweden)


    Because pyrogenic (fever-inducing) compounds on ambient particles may play an important role for particle toxicity, simple methods to measure pyrogens on particles are needed. Here we have used a modified in vitro pyrogen test (IPT) to study the release of interleukin 1beta (IL-1beta) in whole human blood exposed to respirable road-dust particles (RRDP). Road dusts were collected from the roadside at six different streets in three Swedish cities and particles with a diameter less than 10 mum (RRDP) were prepared by a water sedimentation procedure followed by lyophilisation. RRDP (200 mul of 1 - 10{sup 6} ng/ml) were mixed with 50 mul whole blood and incubated at 37 deg. C overnight before IL-1beta was analysed with chemiluminescence ELISA in 384-well plates. Endotoxin (lipopolysaccharide from Salmonella minnesota), zymosan B and Curdlan (P-1,3-glucan) were used as positive controls. All RRDP samples had a pyrogenic effect and the most active sample produced 1.6 times more IL-1beta than the least active. This formation was of the same magnitude as in samples with 10 ng LPS/ml and was larger than that evoked by zymosan B and Curdlan (by mass basis). The method was sensitive enough to determine formation of IL-1beta in mixtures with 10 ng RRDP/ml or 0.01 ng LPS/ml. The endotoxin inhibitor, polymyxin B (10 mug/ml), strongly reduced the RRDP-induced formation of IL-1beta at 1mug RRDP/ml (around 80 % inhibition), but had only marginal or no effects at higher RRDP-concentrations (10 and 100 mug /ml). In summary, all RRDP tested had a clear pyrogen effect in this in vitro model. Endotoxin on the particles but also other factors contributed to the pyrogenic effect. As opposed to the limulus amebocyte lysate (LAL) assay (which measures endotoxin alone), IPT measures a broad range of pyrogens that may be present on particulate matter. The IPT method thus affords a simple, sensitive and quantitative determination of the total pyrogenic potential of ambient particles.

  12. Modelling of Suspended Sediment Discharge for Masinga ...

    Sedimentation models however, require suspended load as the basic input data. ... at the two mouths of the reservoir, at the confluence, and near the dam wall. ... Dredging out fine sediments, construction of sedimentation basins at the two ...

  13. Space station particulate contamination environment

    Miller, E. R.; Clifton, K. S.


    The origin of particulate contamination on the Space Station will mostly be from pre-launch operations. The adherence and subsequent release of these particles during space flight are discussed. Particle size, release velocity, and release direction are important in determining particle behavior in the vicinity of the vehicle. The particulate environment at the principal science instrument locations is compared to the space shuttle bay environment. Recommendations for possibly decreasing the particulate contamination are presented.

  14. Stability of suspended graphene under Casimir force

    Chudnovsky, E. M.; Zarzuela, R.


    We consider a graphene sheet suspended above a conducting surface. Treating graphene as an elastic membrane subjected to Casimir force, we study its stability against sagging towards the conductor. There exists a critical elevation at the edges below which the central part of the suspended graphene nucleates a trunk that sinks under the action of the Casimir force. The dependence of the critical elevation on temperature, dimensions, and the elastic stress applied to the graphene sheet is computed.

  15. Lakewide monitoring of suspended solids using satellite data. [Lake Superior water reclamation

    Sydor, M. (Principal Investigator)


    In anticipation of using LANDSAT and Nimbus 7 coastal zone color scanner data to observe the decrease in suspended solids in Lake Superior following cessation of the dumping of taconite tailings, a series of lakewide sampling cruises was conducted to make radiometric measurements at a lake level. A means for identifying particulates and measuring their concentration from LANDSAT data was developed. The initial distribution of chemical parameters in the extreme western arm of the lake, where the concentration gradients are high, is to be based on the LANDSAT data. Subsequent lakewide dispersal and distribution is to be based on the coastal zone color scanner data.

  16. Respirators: APR Issuer Self Study 33461

    Chochoms, Michael [Los Alamos National Laboratory


    Respirators: APR Issuer Self-Study (course 33461) is designed to introduce and familiarize employees selected as air-purifying respirator (APR) issuers at Los Alamos National Laboratory (LANL) with the responsibilities, limitations, procedures, and resources for issuing APRs at LANL. The goal is to enable these issuers to consistently provide proper, functioning APRs to authorized users

  17. 78 FR 18535 - Respirator Certification Fees


    ....\\4\\ A summary of market segmentation, by respirator type, is offered in Table 1, below. \\4\\ Frost... be determined on a case-by-case basis; considerations will include an assessment of the manufacturer... and paint applications and hazardous materials management. Of the U.S. respirator market of...

  18. Mitochondrial respiration is sensitive to cytoarchitectural breakdown.

    Kandel, Judith; Angelin, Alessia A; Wallace, Douglas C; Eckmann, David M


    An abundance of research suggests that cellular mitochondrial and cytoskeletal disruption are related, but few studies have directly investigated causative connections between the two. We previously demonstrated that inhibiting microtubule and microfilament polymerization affects mitochondrial motility on the whole-cell level in fibroblasts. Since mitochondrial motility can be indicative of mitochondrial function, we now further characterize the effects of these cytoskeletal inhibitors on mitochondrial potential, morphology and respiration. We found that although they did not reduce mitochondrial inner membrane potential, cytoskeletal toxins induced significant decreases in basal mitochondrial respiration. In some cases, basal respiration was only affected after cells were pretreated with the calcium ionophore A23187 in order to stress mitochondrial function. In most cases, mitochondrial morphology remained unaffected, but extreme microfilament depolymerization or combined intermediate doses of microtubule and microfilament toxins resulted in decreased mitochondrial lengths. Interestingly, these two particular exposures did not affect mitochondrial respiration in cells not sensitized with A23187, indicating an interplay between mitochondrial morphology and respiration. In all cases, inducing maximal respiration diminished differences between control and experimental groups, suggesting that reduced basal respiration originates as a largely elective rather than pathological symptom of cytoskeletal impairment. However, viability experiments suggest that even this type of respiration decrease may be associated with cell death.

  19. Airborne Particulate Threat Assessment

    Patrick Treado; Oksana Klueva; Jeffrey Beckstead


    Aerosol threat detection requires the ability to discern between threat agents and ambient background particulate matter (PM) encountered in the environment. To date, Raman imaging technology has been demonstrated as an effective strategy for the assessment of threat agents in the presence of specific, complex backgrounds. Expanding our understanding of the composition of ambient particulate matter background will improve the overall performance of Raman Chemical Imaging (RCI) detection strategies for the autonomous detection of airborne chemical and biological hazards. Improving RCI detection performance is strategic due to its potential to become a widely exploited detection approach by several U.S. government agencies. To improve the understanding of the ambient PM background with subsequent improvement in Raman threat detection capability, ChemImage undertook the Airborne Particulate Threat Assessment (APTA) Project in 2005-2008 through a collaborative effort with the National Energy Technology Laboratory (NETL), under cooperative agreement number DE-FC26-05NT42594. During Phase 1 of the program, a novel PM classification based on molecular composition was developed based on a comprehensive review of the scientific literature. In addition, testing protocols were developed for ambient PM characterization. A signature database was developed based on a variety of microanalytical techniques, including scanning electron microscopy, FT-IR microspectroscopy, optical microscopy, fluorescence and Raman chemical imaging techniques. An automated particle integrated collector and detector (APICD) prototype was developed for automated collection, deposition and detection of biothreat agents in background PM. During Phase 2 of the program, ChemImage continued to refine the understanding of ambient background composition. Additionally, ChemImage enhanced the APICD to provide improved autonomy, sensitivity and specificity. Deliverables included a Final Report detailing our

  20. Contribution of root respiration to soil respiration in a C3/C4 mixed grassland

    Wei Wang; Kenji Ohse; Jianjun Liu; Wenhong Mo; Takehisa Oikawa


    The spatial and temporal variations of soil respiration were studied from May 2004 to June 2005 in a C3/C4 mixed grassland of Japan. The linear regression relationship between soil respiration and root biomass was used to determine the contribution of root respiration to soil respiration. The highest soil respiration rate of 11.54 mol m–2 s–1 was found in August 2004 and the lowest soil respiration rate of 4.99 mol m–2 s–1 was found in April 2005. Within-site variation was smaller than seasonal change in soil respiration. Root biomass varied from 0.71 kg m–2 in August 2004 to 1.02 in May 2005. Within-site variation in root biomass was larger than seasonal variation. Root respiration rate was highest in August 2004 (5.7 mol m–2 s–1) and lowest in October 2004 (1.7 mol m–2 s–1). Microbial respiration rate was highest in August 2004 (5.8 mol m–2 s–1) and lowest in April 2005 (2.59 mol m–2 s–1). We estimated that the contribution of root respiration to soil respiration ranged from 31% in October to 51% in August of 2004, and from 45% to 49% from April to June 2005.


    王保栋; 战闰; 徐明德


    The vertical fluxes and molar ratios of carbon, nitrogen and phosphorus of suspended particulate matter in the Yellow Sea were studied based on the analysis of suspended particulate matter, sediments and sinking particles obtained by use of moored sediment traps. The POC:PON ratios indicate that most of the particulate organic matter in the Yellow Sea water column comes from marine life rather than the continent. The vertical fluxes of SPM, POC, PON and POP in the Yellow Sea are much higher than those in other seas over the world, and present a typical pattern in shallow epicontinental seas. The estimated residence time of the bioactive elements showed that the speed of the biogeochemical process of materials in the Yellow Sea is much shorter than that in the open ocean as there was high primary productivity in this region.

  2. Nitrate respiration associated with detrital aggregates in aerobic bottom waters of the abyssal NE Pacific

    Wolgast, D. M.; Carlucci, A. F.; Bauer, J. E.

    Rates of nitrate utilization in tube core respirometers (TCR) placed over aggregates on the seafloor at an abyssal site (Station M) in the eastern North Pacific Ocean increased at times of high particle flux. In the presence of aggregates, both oxygen and nitrate were used in respiration. The ratio of O 2 : NO 3 concentrations in ambient waters was 3.9, while O 2 : NO 3 utilization rates in TCR overlying and TCR aggregate pore waters were 2.6 and 0.6, respectively. We postulated that denitrification was occurring in microzones of the particle-rich oxygenated (135 μM) waters. To test this, nitrate respiration was measured aboard a ship in oxygen-minimum (˜26 μM) water supplemented with particulate matter collected by a surface net tow. Dissolved oxygen consumption occurred immediately, followed by nitrate utilization while oxygen was still present. Calculations from cell densities indicated 0.6 μM of the original 42 μM of nitrate was assimilated into bacterial biomass during 36 h of incubation, suggesting the major portion of the utilized nitrate was used in respiration. Nitrate utilization rates in the in situ incubation study and those of the shipboard experiment were 3.1 and 2.7 μM d -1, respectively. The results of the present studies suggest nitrate respiration occurs in microzones of aggregates in oxygenated bottom waters at times of high particle flux and causes some loss of fixed nitrogen.

  3. Desorption of radioactive cesium by seawater from the suspended particles in river water.

    Onodera, Masaki; Kirishima, Akira; Nagao, Seiya; Takamiya, Kouichi; Ohtsuki, Tsutomu; Akiyama, Daisuke; Sato, Nobuaki


    In 2011, the accident at the Fukushima-Daiichi nuclear power plant dispersed radioactive cesium throughout the environment, contaminating the land, rivers, and sea. Suspended particles containing clay minerals are the transportation medium for radioactive cesium from rivers to the ocean because cesium is strongly adsorbed between the layers of clay minerals, forming inner sphere complexes. In this study, the adsorption and desorption behaviors of radioactive cesium from suspended clay particles in river water have been investigated. The radioactive cesium adsorption and desorption experiments were performed with two kinds of suspended particulate using a batch method with (137)Cs tracers. In the cesium adsorption treatment performed before the desorption experiments, simulated river water having a total cesium concentration ([(133+137)Cs(+)]total) of 1.3 nM (10(-9) mol/L) was used. The desorption experiments were mainly conducted at a solid-to-liquid ratio of 0.17 g/L. The desorption agents were natural seawater collected at 10 km north of the Fukushima-Daiichi nuclear power plant, artificial seawater, solutions of NaCl, KCl, NH4Cl, and (133)CsCl, and ultrapure water. The desorption behavior, which depends on the preloaded cesium concentration in the suspended particles, was also investigated. Based on the cesium desorption experiments using suspended particles, which contained about 1000 ng/g loaded cesium, the order of cesium desorption ratios for each desorption agent was determined as 1 M NaCl (80%) > 470 mM NaCl (65%) > 1 M KCl (30%) ≈ seawater (natural seawater and Daigo artificial seawater) > 1 M NH4Cl (20%) > 1 M (133)CsCl (15%) ≫ ultrapure water (2%). Moreover, an interesting result was obtained: The desorption ratio in the 470 mM NaCl solution was much higher than that in seawater, even though the Na(+) concentrations were identical. These results indicate that the cesium desorption mechanism is not a simple ion exchange reaction

  4. Data Fusion for Improved Respiration Rate Estimation

    Gari D. Clifford


    Full Text Available We present an application of a modified Kalman-Filter (KF framework for data fusion to the estimation of respiratory rate from multiple physiological sources which is robust to background noise. A novel index of the underlying signal quality of respiratory signals is presented and then used to modify the noise covariance matrix of the KF which discounts the effect of noisy data. The signal quality index, together with the KF innovation sequence, is also used to weight multiple independent estimates of the respiratory rate from independent KFs. The approach is evaluated both on a realistic artificial ECG model (with real additive noise and on real data taken from 30 subjects with overnight polysomnograms, containing ECG, respiration, and peripheral tonometry waveforms from which respiration rates were estimated. Results indicate that our automated voting system can out-perform any individual respiration rate estimation technique at all levels of noise and respiration rates exhibited in our data. We also demonstrate that even the addition of a noisier extra signal leads to an improved estimate using our framework. Moreover, our simulations demonstrate that different ECG respiration extraction techniques have different error profiles with respect to the respiration rate, and therefore a respiration rate-related modification of any fusion algorithm may be appropriate.

  5. Respirable dust and silica exposure among World Trade Center cleanup workers.

    Pavilonis, Brian T; Mirer, Franklin E


    The cleanup effort following the destruction of the World Trade Center (WTC) was unprecedented and involved removal of 1.8 million tons of rubble over a nine-month period. Work at the site occurred 24 hr a day, 7 days a week and involved thousands of workers during the process. The Occupational Safety and Health Administration (OSHA) conducted personal and area exposure sampling during the cleanup of the site. Secondary data analysis was performed on OSHA air sampling data for respirable dust and silica from September 2001 to June 2002 at the WTC recovery site to characterize workers' exposure. Results for silica and respirable particulate were stratified by area and personal samples as well as job task for analysis. Of 1108 samples included in the analysis, 693 were personal and 415 were area. The mean result for personal silica samples was 42 μg/m(3) (Range: 4.2-1800 μg/m(3)). Workers identified as drillers had the highest mean silica exposure (72 μg/m(3); range: 5.8-800 μg/m(3)) followed by workers identified as dock builders (67 μg/m(3); range: 5.8-670 μg/m(3)). The mean result for personal samples for respirable particulate was 0.44 mg/m(3) (range: 0.00010-13 mg/m(3)). There were no discernable trends in personal respirable dust and silica concentrations with date.

  6. Suspended sediment control and water quality conservation through riparian vegetation:

    Pavanelli, D.; Cavazza, C.; Correggiari, S.


    Soil erosion and Suspended Sediment River are strongly related in the Apennines catchments which are generally characterised by a clayey lithology and impermeable soils and extensive and severe erosion and slope stability problems. In fact the suspended sediment yield represents one of the most reliable tools to assess real basin soil loss (Pavanelli and Pagliarani, 2002; Pavanelli and Rigotti, 2007) from the surface rain erosive features in a mountain watershed, as rills and interrills erosion, gullies, bad-lands (calanchi basins). Suspended sediment yield is known to imply several detrimental consequences: soil losses from agricultural land, worsening of the quality of the water, clogging of water supply filters and reservoir siltation. In addition, suspended sediment yield is also one of the main vector for pollutants and nutrients: various studies have already proved how nitrogen content has been constantly rising in aquifers and surface waters [Böhlke and Denver, 1995]. Finer particles and their aggregates have been proved to be the preferential vehicle for particulate nitrogen [Droppo et al., 1997; Ongley et al., 1992]. In one research [Pavanelli and al. 2006] four Apennines torrents (Gaiana, Sillaro, Savena and Lavino) with mountain basins ranging from 8.7 to 139 Km2 were monitored via automatic sampling devices, the samples of water collected were analysed to characterise suspended solids in terms of their grain size distribution and total nitrogen with respect to the source of eroded area in the catchment. Preliminary results [Pavanelli and al. 2007] seem to show the existence of a direct relationship between nitrogen concentration and finer particle concentration (position within the catchment and the availability of suspended particles. The results seem to indicate hillsides as main sources of suspended sediment to the torrents monitored. The problem of controlling the river suspended sediment concentration can be tackled by increasing the riparian

  7. Recommended test methods and pass/fail criteria for a respirator fit capability test of half-mask air-purifying respirators.

    Zhuang, Ziqing; Bergman, Michael; Lei, Zhipeng; Niezgoda, George; Shaffer, Ronald


    This study assessed key test parameters and pass/fail criteria options for developing a respirator fit capability (RFC) test for half-mask air-purifying particulate respirators. Using a 25-subject test panel, benchmark RFC data were collected for 101 National Institute for Occupational Safety and Health-certified respirator models. These models were further grouped into 61 one-, two-, or three-size families. Fit testing was done using a PortaCount® Plus with N95-Companion accessory and an Occupational Safety and Health Administration-accepted quantitative fit test protocol. Three repeated tests (donnings) per subject/respirator model combination were performed. The panel passing rate (PPR) (number or percentage of the 25-subject panel achieving acceptable fit) was determined for each model using five different alternative criteria for determining acceptable fit. When the 101 models are evaluated individually (i.e., not grouped by families), the percentages of models capable of fitting >75% (19/25 subjects) of the panel were 29% and 32% for subjects achieving a fit factor ≥100 for at least one of the first two donnings and at least one of three donnings, respectively. When the models are evaluated grouped into families and using >75% of panel subjects achieving a fit factor ≥100 for at least one of two donnings as the PPR pass/fail criterion, 48% of all models can pass. When >50% (13/25 subjects) of panel subjects was the PPR criterion, the percentage of passing models increased to 70%. Testing respirators grouped into families and evaluating the first two donnings for each of two respirator sizes provided the best balance between meeting end user expectations and creating a performance bar for manufacturers. Specifying the test criterion for a subject obtaining acceptable fit as achieving a fit factor ≥100 on at least one out of the two donnings is reasonable because a majority of existing respirator families can achieve an PPR of >50% using this criterion

  8. Salinity and suspended matter variations in the Tay estuary

    McManus, John


    The concept of salinity-induced density layering in estuaries was first demonstrated from the upper reaches of the Tay. In this study the nature of the layering and its variation through the tidal cycle is demonstrated from time series of observations taken at many locations within this estuary. Thorough mixing of the waters on the rising tide, as defined by depth profiles of salinity, is commonly replaced by salinity layering during the high water slack period. This condition continues into the falling tide. Frequently the mixed waters are abruptly replaced by stratified waters within the half-hourly sampling interval. This is attributed to the activity of longitudinal fronts, manifest as surficial foam bands, along which water masses shear past each other on both the flood and ebb tides. Offsetting of transverse salinity coutours along the fronts is introduced to explain apparent complexities in surface water salinity distributions measured at high water slack. Suspended particulate matter concentrations increase towards the limit of the saline water intrusion before decreasing headwards into the freshwater zone of the estuary. The suspensions in the water column may also be displaced by the lateral offsetting of the waters along the fronts. The recognition of the presence of fronts, and a knowledge of their impact on the estuarine waters may provide an alternative means of understanding the flow characteristics of these challenging water bodies. The techniques of spatial and temporal averaging normally widely used today may not be the most realistic approach to analysis of the flows.

  9. 78 FR 40000 - Method for the Determination of Lead in Total Suspended Particulate Matter


    ... currently designated FEMs are retained. This action avoids any disruption to existing Pb monitoring networks... comparison for determining equivalence of candidate FEMs. This method replaces the existing method in 40 CFR... currently designated FEMs are retained. The EPA believes this is appropriate because the new FRM is based on...

  10. 78 FR 8066 - Method for the Determination of Lead in Total Suspended Particulate Matter


    ... proposing to make the existing FRM for Pb a new FEM, and retain currently designated FEMs. This proposed... NAAQS and also serve as the standard of comparison for determining equivalence of candidate FEMs. The... Appendix G would become an approved FEM and the currently designated FEMs would be retained. The EPA...

  11. Signature of terrestrial influence on nitrogen isotopic composition of suspended particulate

    Kumar, S.; Ramesh, R.; Sheshshayee, M.S.; Sardessai, S.; Patel, P.P.

    du ring their res i dence in th eir parent bodies. Cosmogenic records i n dicate a larg e size ( greaterequal 1 m) for the Kendrapara meteoroid that has spent ~5 million years in interplanetary space follo w ing its ejection from its parent... of these objects provide us insight into the processes governing the very earl y evol u tion of the solar system and also the mode of its probable origin 1 . Meteorite studies in general provide clues to u n derstand the evolution of their parent bodies...

  12. A factor analysis-multiple regression model for source apportionment of suspended particulate matter

    Okamoto, Shin'ichi; Hayashi, Masayuki; Nakajima, Masaomi; Kainuma, Yasutaka; Shiozawa, Kiyoshige

    A factor analysis-multiple regression (FA-MR) model has been used for a source apportionment study in the Tokyo metropolitan area. By a varimax rotated factor analysis, five source types could be identified: refuse incineration, soil and automobile, secondary particles, sea salt and steel mill. Quantitative estimations using the FA-MR model corresponded to the calculated contributing concentrations determined by using a weighted least-squares CMB model. However, the source type of refuse incineration identified by the FA-MR model was similar to that of biomass burning, rather than that produced by an incineration plant. The estimated contributions of sea salt and steel mill by the FA-MR model contained those of other sources, which have the same temporal variation of contributing concentrations. This symptom was caused by a multicollinearity problem. Although this result shows the limitation of the multivariate receptor model, it gives useful information concerning source types and their distribution by comparing with the results of the CMB model. In the Tokyo metropolitan area, the contributions from soil (including road dust), automobile, secondary particles and refuse incineration (biomass burning) were larger than industrial contributions: fuel oil combustion and steel mill. However, since vanadium is highly correlated with SO 42- and other secondary particle related elements, a major portion of secondary particles is considered to be related to fuel oil combustion.

  13. Suspended particulate matter in the White Sea: the results of long-term interdisciplinary research

    Kravchishina, M.; Klyuvitkin, A.; Filippov, A.; Novigatsky, A.; Politova, N.; Shevchenko, V.; Lisitzin, A.


    The spatial and temporal variations in SPM concentration in the White Sea, Russia, are directly (mineral particles from the water basin) or indirectly ("blossom" of diatoms due to supply of nutrients) caused by river runoff. Interannual variations in SPM concentration for the White Sea are low and do not exceed 18% (2003–2010); hence, they are statistically insignificant.

  14. Suspended particulate matter in the White Sea: the results of long-term interdisciplinary research

    Kravchishina, M.; Klyuvitkin, A.; Filippov, A.; Novigatsky, A.; Politova, N.; Shevchenko, V.; Lisitzin, A.


    The spatial and temporal variations in SPM concentration in the White Sea, Russia, are directly (mineral particles from the water basin) or indirectly ("blossom" of diatoms due to supply of nutrients) caused by river runoff. Interannual variations in SPM concentration for the White Sea are low and do not exceed 18% (2003-2010); hence, they are statistically insignificant.

  15. The effect of gender and respirator brand on the association of respirator fit with facial dimensions.

    Oestenstad, R Kent; Elliott, Leshan J; Beasley, T Mark


    This study examined the association of facial dimensions with respirator fit considering the effect of gender and respirator brand. Forty-one subjects (20 white females and 21 white males) participated in the study. Each subject was measured for 12 facial dimensions using anthropometric sliding and spreading calipers and a steel measuring tape. Three quantitative fit tests were conducted with the same subject wearing one size of three different brands of half-mask respirators resulting in a total of nine fit tests. Linear mixed model analysis was used to model respirator fit as a function of gender and respirator brand while controlling for facial dimensions. Results indicated that the gender by respirator brand interaction was not statistically significant (p = 0.794), and there was no significant difference in respirator fit between males and females (p = 0.356). There was a significant difference in respirator fit among respirator brands (p brand, six separate linear mixed models were fit to assess which facial dimensions most strongly relate to respirator fit using a "one variable at a step" backward elimination procedure. None of the 12 facial dimensions were significantly associated with respirator fit in all six models. However, bigonial breadth and menton-nasion length were significantly associated with respirator fit in five of the six models, and biectoorbitale breadth, bizygomatic breadth, and lip width were significantly associated with respirator fit in four of the six models. Although this study resulted in significant findings related to the correlation of respirator fit with menton-nasion length and lip width (the dimensions currently used to define the half-mask respirator test panel), other facial dimensions were also shown to be significantly associated with respirator fit. Based on these findings and findings from previous studies, it is suggested that other facial dimensions including bigonial breadth, biectoorbitale breadth, and bizygomatic

  16. Aerobic respiration in the Archaean?

    Towe, K M


    The Earth's atmosphere during the Archaean era (3,800-2,500 Myr ago) is generally thought to have been anoxic, with the partial pressure of atmospheric oxygen about 10(-12) times the present value. In the absence of aerobic consumption of oxygen produced by photosynthesis in the ocean, the major sink for this oxygen would have been oxidation of dissolved Fe(II). Atmospheric oxygen would also be removed by the oxidation of biogenic methane. But even very low estimates of global primary productivity, obtained from the amounts of organic carbon preserved in Archaean rocks, seem to require the sedimentation of an unrealistically large amount of iron and the oxidation of too much methane if global anoxia was to be maintained. I therefore suggest that aerobic respiration must have developed early in the Archaean to prevent a build-up of atmospheric oxygen before the Proterozoic. An atmosphere that contained a low (0.2-0.4%) but stable proportion of oxygen is required.

  17. Water column particulate matter: A key contributor to phosphorus regeneration in a coastal eutrophic environment, the Chesapeake Bay: Particulate phosphorus in the Chesapeake Bay

    Li, Jiying [Department of Plant and Soil Sciences, University of Delaware, Newark Delaware USA; Reardon, Patrick [Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland Washington USA; Now at NMR Facility, Oregon State University, Corvallis Oregon USA; McKinley, James P. [Geochemistry Group, Pacific Northwest National Laboratory, Richland Washington USA; Joshi, Sunendra R. [Department of Plant and Soil Sciences, University of Delaware, Newark Delaware USA; Bai, Yuge [Department of Plant and Soil Sciences, University of Delaware, Newark Delaware USA; Bear, Kristi [Department of Plant and Soil Sciences, University of Delaware, Newark Delaware USA; Jaisi, Deb P. [Department of Plant and Soil Sciences, University of Delaware, Newark Delaware USA


    Particulate phosphorus (PP) in the water column is an essential component of phosphorus (P) cycling in aquatic ecosystems yet its composition and transformations remain largely uncharacterized. To understand the roles of suspended particulates on regeneration of inorganic P (Pi) into the water column as well as sequestration into more stable mineral precipitates, we studied seasonal variation in both organic and inorganic P speciation in suspended particles in three sites in the Chesapeake Bay using sequential P extraction, 1D (31P) and 2D (1H-31P) nuclear magnetic resonance (NMR) spectroscopies, and electron microprobe analyses (EMPA). Remineralization efficiency of particulate P average 8% and 56% in shallow and deep sites respectively, suggesting the importance of PP remineralization is in resupplying water column Pi. Strong temporal and spatial variability of organic P composition, distributions, and remineralization efficiency were observed relating to water column parameters such as temperature and redox conditions: concentration of orthophosphate monoesters and diesters, and diester-to-monoester (D/M) ratios decreased with depth. Both esters and the D/M ratios were lower in the hypoxic July and September. In contrast, pyrophosphate and orthophosphate increased with depth, and polyphosphates was high in the anoxic water column. Sequential extraction and EMPA analyses of the suspended particles suggest presence of Ca-bound phosphate in the water column. We hypothesize authigenic precipitation of carbonate fluorapatite and/or its precursor mineral(s) in Pi rich water column, supported by our thermodynamic calculations. Our results, overall, reveal the important role suspended particles play in P remineralization and P sequestration in the Chesapeake Bay water column, provide important implications on P bioavailability and P sinks in similar eutrophic coastal environments.

  18. Erosion of particulate organic material from an Andean river and its delivery to the Amazon Basin

    Clark, Kathryn; Hilton, Robert; West, A. Joshua; Robles Caceres, Arturo; Grocke, Darren; Marthews, Toby; Asner, Greg; New, Mark; Mahli, Yadvinder


    Organic carbon and nutrients discharged by mountainous rivers can play an important role in biogeochemical cycles from regional to global scales. The eastern Andes host productive forests on steep, rapidly eroding slopes, a combination that is primed to deliver sediment, carbon and nutrients to the lowland Amazon River. We quantify clastic sediment and particulate organic carbon (POC) discharge for the Kosñipata River, Peru, an Andean tributary of the Madre de Dios River, using suspended sediment samples and discharge measurements over one year at two gauging stations. Calculations of sediment yield on the basis of this data suggest that the Madre de Dios basin may have erosion rates ˜10 times greater than the Amazon Basin average. The total POC yield over the sampling period was up to five times higher than the yield in the lowland Amazon Basin, with most POC (70-80%) exported between December and March in the wet season. We use radiocarbon, stable C isotopes and C/N ratios to distinguish between the erosion and discharge of POC from sedimentary rocks (petrogenic POC) and POC eroded from the modern terrestrial biosphere, from vegetation and soil (biospheric POC). We find that biospheric POC discharge was significantly enhanced during flood events, over that of clastic sediment and petrogenic POC. The ultimate fate of the eroded POC may play a central role in the net carbon budget of Andean forest. In these forests, net productivity minus heterotrophic respiration is close to zero at the scale of forest plots, and the erosion of biospheric POC by this Andean river is sufficiently rapid that its fate downstream (sedimentary burial/preservation versus oxidation/degradation) may determine whether the mountain forest is a carbon sink or source to the atmosphere. In addition, the measured discharge of petrogenic POC suggests that fluxes from the Andes may be considerably higher than measured downstream in the Madeira River. If this petrogenic POC is oxidised rather

  19. Metal removal via particulate material in a lowland river system.

    Webster-Brown, J G; Dee, T J; Hegan, A F


    Twelve month surveys of acid-soluble and dissolved trace metal concentrations in the lower Waikato River (in 1998/9 and 2005/6) showed abnormally low particulate Fe, Mn, Cu, Pb and Zn concentrations and mass flux in autumn, when the suspended particulate material (SPM) had a relatively high diatom and organic carbon content, and low Fe and Al content. Dissolved Mn, Cu and Zn concentrations also decreased in autumn, while dissolved Fe and Pb concentrations were unaffected. While SPM settlement under the low river flow conditions present in autumn can explain the removal of particulate metals, it does not explain dissolved metal removal. SPM-metal interaction was therefore investigated using seasonal monitoring data, experimental adsorption studies, sequential extraction and geochemical modelling. Pb binding to SPM occurred predominantly via Fe-oxide surfaces, and could be reliably predicted using surface complexation adsorption modelling. Dissolved Mn concentrations were controlled by the solubility of Mn oxide, but enhanced removal during autumn could be attributed to uptake by diatoms. Zn and Cu were also adsorbed on Fe-oxide in the SPM, but removal from the water column in autumn appeared augmented by Zn adsorption onto Mn-oxide, and Cu adsorption onto the organic extracellular surfaces of the diatoms.

  20. Bioaccessibility of palladium and platinum in urban aerosol particulates

    Puls, Christoph; Limbeck, Andreas; Hann, Stephan


    To evaluate potential health hazards caused by environmental Platinum Group Elements (PGEs), bioaccessibility of the metals in question needs to be assessed. To gain appropriate data, airborne particulate matter samples of different size fractions (total suspended particles as well as PM10 and PM2.5) were taken in downtown Vienna, an urban site primarily polluted by traffic. Total PGE concentrations in these samples were in the low picogram per cubic meter range, as determined by ID-ICP-MS after microwave digestion. For elimination of elements interfering with the accurate quantification, the digested samples were subjected to a cleaning procedure involving cation exchange. For determination of the bioaccessible fraction, it was assumed that inhaled particles are removed from the respiratory system by mucociliary clearance and subsequently ingested. Accordingly, the solubility of PGE in synthetic gastric juice was investigated by batch extraction of particulate matter samples followed by microwave assisted UV-digestion, cation exchange cleanup and ID-ICP-MS. The acquired data was used to calculate the bioaccessible fraction of Pd and Pt in airborne particulate matter. Average GIT-extractable fractions for Pd and Pt in TSP were 41% and 27%, in PM10 34% and 26%, respectively, thus exceeding previously determined values for bioaccessibility of PGE from ground catalyst materials by up to an order of magnitude.

  1. Particulates and the cycling of lead in Ullswater, Cumbria

    Everard, M.; Denny, P.


    Ullswater has been affected by former lead mining in the catchment area. An attempt is made to investigate how lead in the lake is re-distributed within the littoral zones. Concentrations in the lakewater are low particulates including phytoplankton, seston and gelatinous ooze overlying lead-enriched sediments can be values from 1.3 to >6.0 and 26 mg Pb g/sup -1/ dry weight respectively. During turbulent conditions, contaminated phytoplankton, settled algae and some of the gelatinous ooze are brought in to near-homogenous suspension within the water column. In calm conditions, settlement of particulates occurs and a rate-zonal distribution results such that, in a vertical column of water, the finer particles in the upper layers have lower concentrations of lead per unit volume of water than the lower layers. In non-turbulent conditions, the particles which settle on all submerged surfaces form a tenuous layer termed ecton. Aufwuchs becomes coated by ecton but the latter is readily re-suspended by disturbances. The intimate contact, and the similarity of concentrations of lead in Aufwuchs and ecton from any one sample, suggests that metal flux occurs between the two. It is concluded that the variety of particulates which comprise the ecton distribute lead during turbulence. In calm conditions the ecton settles on all submerged surfaces and provides a mechanism for transfer of lead into the littoral food web.

  2. Probing soil respiration process of grasslands


    @@ Soil respiration, which is primarily the only output approach for CO2 exchanges in soils between the global terrestrial ecosystem and the atmosphere,exerts a direct influence on the speed of carbon turnover rate of the soil.

  3. Characterization of Carbon Particulates in the Exit Flow of a Plasma Pyrolysis Assembly (PPA) Reactor

    Green, Robert D.; Meyer, Marit E.; Agui, Juan H.; Berger, Gordon M.; Vijayakumar, R.; Abney, Morgan B.; Greenwood, Zachary


    The ISS presently recovers oxygen from crew respiration via a Carbon Dioxide Reduction Assembly (CRA) that utilizes the Sabatier chemical process to reduce captured carbon dioxide to methane (CH4) and water. In order to recover more of the hydrogen from the methane and increase oxygen recovery, NASA Marshall Space Flight Center (MSFC) is investigating a technology, plasma pyrolysis, to convert the methane to acetylene. The Plasma Pyrolysis Assembly (or PPA), achieves 90% or greater conversion efficiency, but a small amount of solid carbon particulates are generated as a side product and must be filtered before the acetylene is removed and the hydrogen-rich gas stream is recycled back to the CRA. In this work, we present the experimental results of an initial characterization of the carbon particulates in the PPA exit gas stream. We also present several potential options to remove these carbon particulates via carbon traps and filters to minimize resupply mass and required downtime for regeneration.

  4. Photothermoelectric effect in suspended semiconducting carbon nanotubes.

    Deborde, Tristan; Aspitarte, Lee; Sharf, Tal; Kevek, Joshua W; Minot, Ethan D


    We have performed scanning photocurrent microscopy measurements of field-effect transistors (FETs) made from individual ultraclean suspended carbon nanotubes (CNTs). We investigate the spatial-dependence, polarization-dependence, and gate-dependence of photocurrent and photovoltage in this system. While previous studies of surface-bound CNT FET devices have identified the photovoltaic effect as the primary mechanism of photocurrent generation, our measurements show that photothermoelectric phenomena play a critical role in the optoelectronic properties of suspended CNT FETs. We have quantified the photothermoelectric mechanisms and identified regimes where they overwhelm the photovoltaic mechanism.

  5. Magnetically suspended momentum wheels for spacecraft stabilization

    Henrikson, C. H.; Lyman, J.; Studer, P. A.


    Magnetic bearings for spacecraft momentum wheels offer the promise of low friction and unlimited life. This paper describes how magnetic bearings work and their advantages and disadvantages. The present status of magnetic bearings is described and examples are shown of the various and widely-different magnetically suspended momentum wheels that have been built to date. These include wheels whose bearings exhibit high stiffness and wheels with zero-power suspensions. The future of magnetically suspended momentum wheels is discussed including the possibility of wheels with neither spokes nor shaft.

  6. Electrodialytic remediation of suspended mine tailings

    Hansen, Henrik K.; Rojo, Adrian; Pino, Denisse;


    This work shows the laboratory results of nine electrodialytic remediation experiments on copper mine tailings. A newly designed remediation cell, where the solids were kept in suspension by airflow, was tested. The results show that electric current could remove copper from suspended tailings...... experiment at 40 mA, with approximately 137.5 g mine tailings on dry basis. The removal for a static (baseline) experiment only amounted 15% when passing approximately the same amount of charge through 130 g of mine tailings. The use of air bubbling to keep the tailings suspended increased the removal...

  7. Effect of Music on Emotions and Respiration

    NOGUCHI Kengo:筆頭著者; MASAOKA Yuri; SATOH Kanako; Kato, Nobumasa; Homma, Ikuo


    In the present study we investigated whether the emotional state induced by music can change respiratory rate (RR), tidal volume (VT), minute ventilation (VE), and end-tidal CO2concentration (ETCO2). In a pioneering study investigating the effect of music on respiration, the music of Stockhausen and Chopin was used. In the present study, we examined the effects of the same musical stimuli used in that study on respiration. Each stimulus (Stockhausen, Chopin, and silence) was delivered for 30 ...

  8. [Effects of Tillage on Soil Respiration and Root Respiration Under Rain-Fed Summer Corn Field].

    Lu, Xing-li; Liao, Yun-cheng


    To explore the effects of different tillage systems on soil respiration and root respiration under rain-fed condition. Based on a short-term experiment, this paper investigated soil respiration in summer corn growth season under four tillage treatments including subsoiling tillage (ST), no tillage (NT), rotary tillage (RT) and moldboard plow tillage (CT). The contribution of root respiration using root exclusion method was also discussed. The results showed that soil respiration rate presented a single peak trend under four tillage methods during the summer corn growing season, and the maximum value was recorded at the heading stage. The trends of soil respiration were as follows: heading stage > flowering stage > grain filling stage > maturity stage > jointing stage > seedling stage. The trends of soil respiration under different tillage systems were as follows: CT > ST > RT > NT. There was a significant correlation between soil respiration rate and soil temperatures (P tillage systems. Therefore, root exclusion method could be used to study the contribution of crop growth to carbon emission, to compare effects of different tillage systems on the contribution of root respiration provides the bases for selecting the measures to slow down the decomposition of soil carbon.

  9. Particulate distribution of plutonium and americium in surface waters from the Spanish Mediterranean coast

    Molero, J.; Sanchez-Cabeza, J.A.; Merino, J.; Vidal-Quadras, A. [Universidad Autonoma de Barcelona (Spain); Vives Batlle, J.; Mitchell, P.I. [University Coll., Dublin (Ireland)


    Measurements of the particulate distribution of plutonium and americium in Spanish Mediterranean coastal waters have been carried out. Plutonium-239,340 and {sup 241}Am concentrations have been measured in suspended particulate matter by filtering (< 0.22 {mu}m) large volume (200-300 litres) sea water samples. Results indicate that particulate plutonium constitutes on average 11 {+-} 4% of the total concentration in sea water. In the case of americium this percentage rises to 45 {+-} 14%. From the {sup 241}Am/{sup 239,240}Pu activity ratios it is clear that suspended particulate matter is enriched in {sup 241}Am relative to {sup 239,240}Pu by a factor 8 {+-} 4. Plutonium and americium in surface Mediterranean coastal waters appear to be fractionated as they present a different transfer rate to the particles. Our measurements allowed us to estimate sediment-water distribution coefficients (K{sub d}), which are a key parameter to interpret differences between the behaviour of plutonium and americium in sea water. Distribution coefficients K{sub d} have been estimated to be (1.4 {+-} 0.5) x 10{sup 5} litres kg{sup -1} for plutonium and (0.9 {+-} 0.5) x 10{sup 6} litres kg{sup -1} for americium in surface Mediterranean coastal waters. (author).

  10. 42 CFR 84.191 - Chemical cartridge respirators; required components.


    ... 42 Public Health 1 2010-10-01 2010-10-01 false Chemical cartridge respirators; required components... Chemical Cartridge Respirators § 84.191 Chemical cartridge respirators; required components. (a) Each chemical cartridge respirator described in § 84.190 shall, where its design requires, contain the...

  11. 78 FR 18601 - Respirator Certification Fees; Public Meeting


    ... HUMAN SERVICES Centers for Disease Control and Prevention Respirator Certification Fees; Public Meeting... stakeholders to present information the impact of an increase on respirator fees on individual respirator manufacturers, the respirator market, or on those industries that rely on NIOSH approved respiratory...

  12. 42 CFR 84.250 - Vinyl chloride respirators; description.


    ... 42 Public Health 1 2010-10-01 2010-10-01 false Vinyl chloride respirators; description. 84.250... Respirators § 84.250 Vinyl chloride respirators; description. Vinyl chloride respirators, including all... escape from vinyl chloride atmospheres containing adequate oxygen to support life, are...

  13. Particulate matter in ambient air - Assessment of health risks. Partiklar i omgivningsluften - en bedoemning av haelsorisker

    Camner, P.


    An investigation, based on literature data and research at SML, was made on deposition of particulate matter in lungs. The importance of mouth and nose breathing respectively is illustrated. By nose breathing only substances <10 micrometers reach the lung as compared to mouth breathing where substances >10 micrometers may deposit in the lung. Swedish limit values of total suspended particulate matter (TSP) of 50 micrograms/cubic meter are recommended as a 6 month mean value and 150 micrograms/cubic meter as a day mean value. For the PM/sub 10/ fraction, which is a measure of the mass fraction of particulate matter in the air that is deposited in the lung by mouth breathing, it is not possible to give a corresponding recommendation. Epidemiological data are lacking and the proposed method of measuring the PM/sub 10/ fraction would underestimate the importance of particles larger than 10 micrometers. (O.S.).


    Ye Zhuang; Stanley J. Miller; Michelle R. Olderbak; Rich Gebert


    A new concept in particulate control, called an advanced hybrid particulate collector (AHPC), is being developed under funding from the U.S. Department of Energy. The AHPC combines the best features of electrostatic precipitators (ESPs) and baghouses in an entirely novel manner. The AHPC concept combines fabric filtration and electrostatic precipitation in the same housing, providing major synergism between the two methods, both in the particulate collection step and in transfer of dust to the hopper. The AHPC provides ultrahigh collection efficiency, overcoming the problem of excessive fine-particle emissions with conventional ESPs, and solves the problem of reentrainment and re-collection of dust in conventional baghouses. Phase I of the development effort consisted of design, construction, and testing of a 5.7-m{sup 3}/min (200-acfm) working AHPC model. Results from both 8-hr parametric tests and 100-hr proof-of-concept tests with two different coals demonstrated excellent operability and greater than 99.99% fine-particle collection efficiency. Since all of the developmental goals of Phase I were met, the approach was scaled up in Phase II to a size of 255 m{sup 3}/min (9000 acfm) (equivalent in size to 2.5 MW) and was installed on a slipstream at the Big Stone Power Plant. For Phase II, the AHPC at Big Stone Power Plant was operated continuously from late July 1999 until mid-December 1999. The Phase II results were highly successful in that ultrahigh particle collection efficiency was achieved, pressure drop was well controlled, and system operability was excellent. For Phase III, the AHPC was modified into a more compact configuration, and components were installed that were closer to what would be used in a full-scale commercial design. The modified AHPC was operated from April to July 2000. While operational results were acceptable during this time, inspection of bags in the summer of 2000 revealed some membrane damage to the fabric that appeared to be

  15. Electrically heated particulate filter restart strategy

    Gonze, Eugene V [Pinckney, MI; Ament, Frank [Troy, MI


    A control system that controls regeneration of a particulate filter is provided. The system generally includes a propagation module that estimates a propagation status of combustion of particulate matter in the particulate filter. A regeneration module controls current to the particulate filter to re-initiate regeneration based on the propagation status.

  16. Acoustic estimation of suspended sediment concentration

    ZHU; Weiqing(


    [1]Morse, P. H. , Theoretical Acoustics, New York: McGraw-Hill Book Co. , 1968.[2]Skudrjuk, E., Die Grundlagen der Akustik, Wien: Springer-Verlag, 1954.[3]Olshevskii, V. V., Statistical Characteristics of Sea Reverberation, Moscow: Nauka Publisher, 1966.[4]Thorne, P. D., Hardcastl, P. J., Soulsby, R. L., Analysis of acoustic measurements of suspended sediments, J. Geop.Res. , 1993, 98: 899.[5]Guo Jijie, Ren Laifa, Li Yunwu, ln-situ calibration of acoustic measurement of suspended sedienmt, Acta Oceanologica Sini-ca, 1998, (20): 120-125.[6]Zhang Shuying, Li Yunwu, Development and application of an acoustic suspended sediemnt monitoring system, Acta Oceanologica Sinica, 1998, (20): 114-119.[7]Zhang Shuying, Li Yunwu, A theoretical analysis of acoustic suspended sediment obsvervation, Acta Acoustica, 1999, (24):267-274.[8]Zhu Weiqing, Pan Feng, Zhu Min et al. , IOA-1 Multi-function Acoustic Doppler Current Profiler (MADCP), OCEAN'2000,Rhode Island, USA.

  17. Bed-levelling experiments with suspended load

    Talmon, A.M.; De Graaff, J.


    Bed-levelling experiments are conducted in a straight laboratory channel. The experiments involve a significant fraction of suspended sediment transport. The purpose of the experiments is to provide data for modelling of the direction of sediment transport on a transverse sloping alluvial river bed,

  18. Batch fabrication of nanotubes suspended between microelectrodes

    Mateiu, Ramona Valentina; Stöckli, T.; Knapp, H. F.


    We report a fabrication method, which uses standard UV-lithography to pattern the catalyst for the chemical vapour deposition(CVD) of suspended double clamped single walled carbon nanotubes. By using an aqueous solution of Fe(NO3)3 the patterning of the catalyst material onto microelectrodes can ...

  19. A depth integrated model for suspended transport

    Galappatti, R.


    A new depth averaged model for suspended sediment transport in open channels has been developed based on an asymptotic solution to the two dimensional convection-diffusion equation in the vertical plane. The solution for the depth averaged concentration is derived from the bed boundary condition and

  20. Scanning tunnelling microscopy of suspended graphene.

    Zan, Recep; Muryn, Chris; Bangert, Ursel; Mattocks, Philip; Wincott, Paul; Vaughan, David; Li, Xuesong; Colombo, Luigi; Ruoff, Rodney S; Hamilton, Bruce; Novoselov, Konstantin S


    Suspended graphene has been studied by STM for the first time. Atomic resolution on mono- and bi-layer graphene samples has been obtained after ridding the graphene surface of contamination via high-temperature annealing. Static local corrugations (ripples) have been observed on both types of structures.

  1. Bed-levelling experiments with suspended load

    Talmon, A.M.; De Graaff, J.


    Bed-levelling experiments are conducted in a straight laboratory channel. The experiments involve a significant fraction of suspended sediment transport. The purpose of the experiments is to provide data for modelling of the direction of sediment transport on a transverse sloping alluvial river bed,

  2. The Shape of Breasts Suspended in Liquid

    De Kleijn, S.C.; Rensen, W.H.J.


    Philips has designed an optical mammography machine. In this machine the breast is suspended into a cup in which the measurements take place. A special fluid is inserted into the cup to prevent the light from going around the breast instead of going through it but this fluid also weakens the signal.

  3. The Shape of Breasts Suspended in Liquid

    De Kleijn, S.C.; Rensen, W.H.J.


    Philips has designed an optical mammography machine. In this machine the breast is suspended into a cup in which the measurements take place. A special fluid is inserted into the cup to prevent the light from going around the breast instead of going through it but this fluid also weakens the signal.

  4. China's Crude Exports to Japan Suspended


    @@ The stalemate of the trade negotiation between China and Japan has recently aroused extensive attention in the two nations. China has suspended oil exports to Japan due to the divergences arising from in the sales negotiation, risking the future of a three-decade long oil shipment program.

  5. Spacecraft Cabin Particulate Monitor Project

    National Aeronautics and Space Administration — We have built and tested an optical extinction monitor for the detection of spacecraft cabin particulates. This sensor sensitive to particle sizes ranging from a few...

  6. Spacecraft Cabin Particulate Monitor Project

    National Aeronautics and Space Administration — We propose to design, build and test an optical extinction monitor for the detection of spacecraft cabin particulates. This monitor will be sensitive to particle...

  7. Suspended solids moderate the degradation and sorption of waste water-derived pharmaceuticals in estuarine waters.

    Aminot, Yann; Fuster, Laura; Pardon, Patrick; Le Menach, Karyn; Budzinski, Hélène


    This study focuses on the fate of pharmaceuticals discharged into an estuarine environment, particularly into the Turbidity Maximum Zone (TMZ). Batch experiments were set up to investigate the factors regulating the degradation of 53 selected pharmaceuticals. Treated effluents from Bordeaux city (France) were mixed with water from the estuarine Garonne River during 4weeks under 6 characterized conditions in order to assess the influence of suspended particulates, sterilization, untreated wastewater input and dilution on the degradation kinetics. Of the 53 pharmaceuticals monitored, 43 were quantified at the initial time. Only 7 exhibited a persistent behavior (e.g. carbamazepine, meprobamate) while biotic degradation was shown to be the main attenuation process for 38 molecules (e.g. abacavir, ibuprofen highly degradable). Degradation was significantly enhanced by increasing concentrations of suspended solids. A persistence index based on the half-lives of the compounds has been calculated for each of the 43 pharmaceuticals to provide a practical estimate of their relative stability. The stability of pharmaceuticals in estuarine environments is likely to be highly variable and attenuated primarily by changes in suspended solid concentration. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Development of emission factors for particulate matter in a school

    Scheff, P.A.; Paulius, V.; Conroy, L.M.


    Schools have complex indoor environments which are influenced by many factors such as number of occupants, building design, office equipment, cleaning agents, and school activities. Like large office buildings, school environments may be adversely influenced by deficiencies in ventilation which may be due to improper operation of HVAC systems, attempts at energy efficiency that limit the supply of outdoor air, or remodeling of building components. Most importantly, children spend up to a third of their time in these structures, and thus it is desirable to better understand the environmental quality in these buildings. A middle school (grades 6 to 8) in a residential section of Springfield, IL was selected for this baseline indoor air quality survey. The school was characterized as having no health complaints, good maintenance schedules, and did not contain carpeting within the classrooms or hallways. The focus of this paper is on the measurements of air quality in the school. The development of emission factors for particulate matter is also discussed. Four indoor locations including the Cafeteria, a Science Classroom, an Art Classroom, and the Lobby outside of the main office, and one outdoor location were sampled for various environmental comfort and pollutant parameters for one week in February of 1997. Integrated samples (8 hour sampling time) for respirable and total particulate matter, and short-term measurements of bioaerosols (two minute samples, three times per day) on three consecutive days were collected at each of the indoor and outdoor sites. Continuous measurements of carbon dioxide, carbon monoxide, temperature and humidity were logged at all locations for five days. Continuous measurements of respirable particulate matter were also collected in the Lobby area. Detailed logs of occupant activity were also collected at each indoor monitoring location throughout the study. Total particle concentrations ranged from 29 to 177 {micro}g/m{sup 3} in the art

  9. Particulate pollution and stone deterioration

    Kendall, Michaela


    The soiling and damage of building surfaces may be enhanced by particulate air pollution, reducing the aesthetic value and lifetimes of historic buildings and monuments. This thesis focuses on the deposition of atmospheric particulate material to building surfaces and identifies potential sources of this material. It also identifies environmental factors influencing two deterioration effects: surface soiling and black crust growth. Two soiling models have been compared to assess their effecti...

  10. Plant Respiration and Climate Change Effects

    Bruhn, D.


    Plant respiration is one of the key processes in terms of an understanding of plant growth and functioning in a future climate. Short- and long-term effects of temperature and CO{sub 2} on plant respiration were investigated in a number of plant species. The experiments tested effects of either temperature and/or CO{sub 2} from the level of individual respiratory enzymes, isolated mitochondria, whole-tissue, and up to the whole canopy level. The short-term effects of elevated atmospheric CO{sub 2} on plant respiration appeared to be less than suggested so far in the literature. This was true both at the tissue level and for intact mitochondria. Respiratory enzymes can, however, be affected already at low CO{sub 2}. These effects did not manifest itself at the tissue level, though, due to low degrees of control on the whole respiratory process exerted by the particular enzymes. Plant respiration on the other hand was affected by long-term growth at elevated atmospheric CO{sub 2}. The findings of the reduced plant respiration at the leaf level were consistent with the literature and potential causes are discussed. Short-term effects of temperature on plant respiration were demonstrated to be dependent on the actual measurement temperature. Further, it is shown that mitochondrial leaf respiration in darkness and light differ substantially in the temperature sensitivity with the former being the far most sensitive. This has implications for modelling CO{sub 2} exchange between vegetation and atmosphere as demonstrated here, since this has so far been neglected. Long-term effects of temperature resulted in respiratory acclimation in a number of species. Respiratory acclimation appeared not to occur to any one single type of growth temperature. The implications of this finding in combination with the timing of acclimation are discussed for modelling respiratory CO{sub 2} release. (au)

  11. Electrical diesel particulate filter (DPF) regeneration

    Gonze, Eugene V; Ament, Frank


    An exhaust system that processes exhaust generated by an engine includes a diesel particulate filter (DPF) that is disposed downstream of the engine and that filters particulates from the exhaust. An electrical heater is disposed upstream of the DPF and selectively heats the exhaust to initiate combustion of the particulates within the exhaust as it passes therethrough. Heat generated by combustion of the particulates induces combustion of particulates within the DPF.

  12. A suspended-particle rosette multi-sampler for discrete biogeochemical sampling in low-particle-density waters

    Breier, J. A.; Rauch, C. G.; McCartney, K.; Toner, B. M.; Fakra, S. C.; White, S. N.; German, C. R.


    To enable detailed investigations of early stage hydrothermal plume formation and abiotic and biotic plume processes we developed a new oceanographic tool. The Suspended Particulate Rosette sampling system has been designed to collect geochemical and microbial samples from the rising portion of deep-sea hydrothermal plumes. It can be deployed on a remotely operated vehicle for sampling rising plumes, on a wire-deployed water rosette for spatially discrete sampling of non-buoyant hydrothermal plumes, or on a fixed mooring in a hydrothermal vent field for time series sampling. It has performed successfully during both its first mooring deployment at the East Pacific Rise and its first remotely-operated vehicle deployments along the Mid-Atlantic Ridge. It is currently capable of rapidly filtering 24 discrete large-water-volume samples (30-100 L per sample) for suspended particles during a single deployment (e.g. >90 L per sample at 4-7 L per minute through 1 {mu}m pore diameter polycarbonate filters). The Suspended Particulate Rosette sampler has been designed with a long-term goal of seafloor observatory deployments, where it can be used to collect samples in response to tectonic or other events. It is compatible with in situ optical sensors, such as laser Raman or visible reflectance spectroscopy systems, enabling in situ particle analysis immediately after sample collection and before the particles alter or degrade.

  13. Optimizing computed tomography pulmonary angiography using right atrium bolus monitoring combined with spontaneous respiration

    Min, Wang; Jian, Li; Rui, Zhai [Jining No. 1 People' s Hospital, Department of Computed Tomography, Jining City, ShanDong Province (China); Wen, Li [Jining No. 1 People' s Hospital, Department of Gastroenterology, Jining, ShanDong (China); Dai, Lun-Hou [Shandong Chest Hospital, Department of Radiology, Jinan, ShanDong (China)


    CT pulmonary angiography (CTPA) aims to provide pulmonary arterial opacification in the absence of significant pulmonary venous filling. This requires accurate timing of the imaging acquisition to ensure synchronization with the peak pulmonary artery contrast concentration. This study was designed to test the utility of right atrium (RA) monitoring in ensuring optimal timing of CTPA acquisition. Sixty patients referred for CTPA were divided into two groups. Group A (n = 30): CTPA was performed using bolus triggering from the pulmonary trunk, suspended respiration and 70 ml of contrast agent (CA). Group B (n = 30): CTPA image acquisition was triggered using RA monitoring with spontaneous respiration and 40 ml of CA. Image quality was compared. Subjective image quality, average CT values of pulmonary arteries and density difference between artery and vein pairs were significantly higher whereas CT values of pulmonary veins were significantly lower in group B (all P < 0.05). There was no significant difference between the groups in the proportion of subjects where sixth grade pulmonary arteries were opacified (P > 0.05). RA monitoring combined with spontaneous respiration to trigger image acquisition in CTPA produces optimal contrast enhancement in pulmonary arterial structures with minimal venous filling even with reduced doses of CA. (orig.)

  14. Preliminary studies of airborne particulate emmisions from the Ampellum S.A. copper smelter, Zlatna, Romania

    Ben J. Williamson


    Full Text Available Preliminary studies have been carried on the characterization of particulate emissions from the Ampellum S.A. copper smelter in the town of Zlatna, Romania. The particulates studied were collected on polycarbonate filters using air pump apparatus and on the surfaces of lichens. Mass of total suspended particulates (TSP and PM10 varied from 19 to 230 μg/m3 and 3 to 146 μg/m3, respectively (PM10/TSP = 0.14 to 1.0, depending on wind direction and proximity to the smelter. Particulates on collection filters from a site directly downwind from the smelter have a mean equivalent spherical diameter (ESD of 0.94 μm (s.d. 1.1 and are dominantly made up of material with the composition of anglesite (PbSO4. The remainder of the material is a heterogeneous mixture of silicates and Fe-, Pb- and Cu-bearing phases. Particulates > 5 μm ESD are rare on the TSP filters, mainly due to the restricted sampling durations possible with the equipment used (<3 hours. Particulates have therefore been studied in the lichen Acarospora smaragdula, which was growing on posts downwind from the smelter and which was found to contain high levels and a broader range of particulates compared with the filters (<5 to 100 μm in diameter. Larger particles include 20-30 μm diameter Fe-rich spherules, which occasionally have Pb- and S-rich encrustations on their surfaces. The nature and possible health effects of the particulates are discussed and recommendations made for future studies.

  15. Energy content of suspended detritus from Arabian Sea

    Krishnakumari, L.; Sumitra-Vijayaraghavan; Royan, J.P.

    Energy components of suspended matter included phytoplankton, zooplankton and detritus inclusive of microorganisms adsorbed to detritus. Of these, detritus contributed most of the energy (98%). The average caloric content of suspended detritus...

  16. Plankton respiration in the Eastern Atlantic Ocean

    Robinson, Carol; Serret, Pablo; Tilstone, Gavin; Teira, Eva; Zubkov, Mikhail V.; Rees, Andrew P.; Woodward, E. Malcolm S.


    Concurrent measurements of dark community respiration (DCR), gross production (GP), size fractionated primary production ( 14C PP), nitrogen uptake, nutrients, chlorophyll a concentration, and heterotrophic and autotrophic bacterial abundance were collected from the upper 200 m of a latitudinal (32°S-48°N) transect in the Eastern Atlantic Ocean during May/June 1998. The mean mixed layer respiration rate was 2.5±2.1 mmol O 2 m -3 d -1 ( n=119) for the whole transect, 2.2±1.1 mmol O 2 m -3 d -1 ( n=32) in areas where chlorophyll a was dissolved oxygen consumption, was 0.8 ( n=11). At the time of the study, plankton community respiration exceeded GP in the picoautotroph dominated oligotrophic regions (Eastern Tropical Atlantic [15.5°S-14.2°N] and North Atlantic Subtropical Gyre [21.5-42.5°N]), which amounted to 50% of the stations sampled along the 12,100 km transect. These regions also exhibited high heterotrophic: autotrophic biomass ratios, higher turnover rates of phytoplankton than of bacteria and low f ratios. However, the carbon supply mechanisms required to sustain the rates of respiration higher than GP could not be fully quantified. Future research should aim to determine the temporal balance of respiration and GP together with substrate supply mechanisms in these ocean regions.

  17. Improving respiration measurements with gas exchange analyzers.

    Montero, R; Ribas-Carbó, M; Del Saz, N F; El Aou-Ouad, H; Berry, J A; Flexas, J; Bota, J


    Dark respiration measurements with open-flow gas exchange analyzers are often questioned for their low accuracy as their low values often reach the precision limit of the instrument. Respiration was measured in five species, two hypostomatous (Vitis Vinifera L. and Acanthus mollis) and three amphistomatous, one with similar amount of stomata in both sides (Eucalyptus citriodora) and two with different stomata density (Brassica oleracea and Vicia faba). CO2 differential (ΔCO2) increased two-fold with no change in apparent Rd, when the two leaves with higher stomatal density faced outside. These results showed a clear effect of the position of stomata on ΔCO2. Therefore, it can be concluded that leaf position is important to guarantee the improvement of respiration measurements increasing ΔCO2 without affecting the respiration results by leaf or mass units. This method will help to increase the accuracy of leaf respiration measurements using gas exchange analyzers. Copyright © 2016 Elsevier GmbH. All rights reserved.

  18. Respiration rate in human pituitary tumor explants.

    Anniko, M; Bagger-Sjöbäck, D; Hultborn, R


    Studies on the respiration rate of human pituitary tumor tissue have so far been lacking in the literature. This study presents the results from four adenomas causing acromegaly, all with different clinical degrees of the disease. Determination of oxygen uptake was performed in vitro with a spectrophotorespirometric system. Pieces of the tumors were explanted to an organ culture system with a high degree of stability. The secretion rate of growth hormone (GH) and prolactin (PRL) was determined. After 4-8 days in vitro, specimens were analyzed for respiration rate. This was approximately 1-1.5 microliters O2/h/micrograms dry weight. The activity of the pituitary tumor tissue was characterized by both the hormone secretion rate and the respiration rate. Particularly active foci were found to occur in the adenoma tissue. Depending on the individual tumor, the GH secretion rate was approximately 0.1-100 pmol/micrograms dry weight/h and PRL secretion rate approximately 0.4-18 micrograms/micrograms dry weight/h. The respiration rate--as is also the hormone secretion rate--is dependent on the time in vitro prior to analysis. The respiration rate in individual tumors is a parameter which does not reflect GH or PRL serum levels or clinical activity of the disease.


    Weigl, J.W.; Warrington, P.M.; Calvin, M.


    The gas exchange by barley leaves of oxygen, carbon dioxide, and added radiocarbon dioxide has been measured in a closed system, with the following results: 1. Carbon dioxide follows different but not necessarily independent paths in photosynthesis and light respiration. 2. The carbon of newly formed photosynthetic intermediates is not available for respiration while the light is on, but becomes immediately respirable in the dark, The enhancement of dark respiration after a light period is largely due to built-up ''photosynthates.'' 3. Photosynthesis proceeds at a measurable rate even at the lowest CO{sub 2} pressures observed (0.03 mm Hg). There is no evidence for a ''threshold'' concentration of carbon dioxide for the reaction; at the lowest concentrations reached, respiration exactly equals assimilation, 4. The mean rate of respiratory CO{sub 2} evolution in strong light was found to be less than that in the dark. Internal re-photosynthesis of respiratory carbon may have been sufficient to account for this effect. 5. The assimilation of C{sup 14}O{sub 2} is about 17% slower than that of C{sup 12}O{sub 2}.

  20. The suspended sentence in French Criminal Law

    Jovašević Dragan


    Full Text Available From the ancient times until today, criminal law has provided different criminal sanctions as measures of social control. These coercive measures are imposed on the criminal offender by the competent court and aimed at limitting the offender's rights and freedoms or depriving the offender of certain rights and freedoms. These sanctions are applied to the natural or legal persons who violate the norms of the legal order and injure or endanger other legal goods that enjoy legal protection. In order to effectively protect social values, criminal legislations in all countries predict a number of criminal sanctions. These are: 1 imprisonment, 2 precautions, 3 safety measures, 4 penalties for juveniles, and 5 sanctions for legal persons. Apart and instead of punishment, warning measures have a significant role in the jurisprudence. Since they emerged in the early 20th century in the system of criminal sanctions, there has been an increase in their application to criminal offenders, especially when it comes to first-time offenders who committed a negligent or accidental criminal act. Warnings are applied in case of crimes that do not have serious consequences, and whose perpetrators are not hardened and incorrigible criminals. All contemporary criminal legislations (including the French legilation provide a warning measure of suspended sentence. Suspended sentence is a conditional stay of execution of sentence of imprisonment for a specified time, provided that the convicted person does not commit another criminal offense and fulfills other obligations. This sanction applies if the following two conditions are fulfilled: a forma! -which is attached to the sentence of imprisonment; and b material -which is the court assessment that the application of this sanction is justified and necessary in a particular case. In many modern criminal legislations, there are two different types of suspended (conditional sentence: 1 ordinary (classical suspended

  1. Experimental study on soil respiration of temperate grassland in China

    WANG Gengchen; DU Rui; KONG Qinxin; L(U) Daren


    Experimental study on soil respiration of typical temperate grassland in Inner Mongolia was conducted in the period of 1998-2000. Closed chamber and GC/FID techniques were used for measurements of soil and plant respiration. Data analysis of three-year measurements show that temperate grassland soil respiration varied in the range of 390-866 gC/m2·a-1 and underwent evident seasonal and annual variations. On average, the soil respiration accounts for 70%-88% of the grassland total respiration. Results also show a stronger relation between the soil respiration and soil temperature in water abundant years. Increased rainfall in 1998 made soil respiration increased, while in the dry years, the relation between soil respiration and soil temperature weakened remarkably. Soit water content plays an important controlling role in soil respiration-temperature interrelation for semiarid grassland.

  2. Soil Respiration During a Soybean-Growing Season


    Soil respiration induced by soybean cultivation over its entire growing season and the factors influencing soil respiration were investigated to examine the seasonal pattern of soil respiration induced by soybean cultivation, explore soybean growth and photosynthesis on soil respiration, and determine the temperature dependence on soil respiration. Soil respiration in a pot experiment with and without soybean plants was sampled using the static chamber method and measured using gas chromatograph. Air temperature was a dominant factor controlling soil respiration rate in unplanted soil. Additionally,rhizosphere respiration comprised 62% to 98% of the soil respiration rate in the soybean-planted soil varying with the soybean growth stages. Harvesting aerial parts of soybean plant caused an immediate drop in the soil respiration rate at that stage. After harvesting the aerial parts of the soybean plant, a highly significant correlation between soil respiration rate and air temperature was found at the flowering stage (P < 0.01), the pod stage (P < 0.01), and the seed-filling stage(P < 0.05). Thus, rhizosphere respiration during the soybean-growing period not only made a great contribution to soil respiration, but also determined the seasonal variation pattern of the soil respiration rate.

  3. Hydrocarbon-enhanced particulate filter regeneration via microwave ignition

    Gonze, Eugene V.; Brown, David B.


    A regeneration method for a particulate filter includes estimating a quantity of particulate matter trapped within the particulate filter, comparing the quantity of particulate matter to a predetermined quantity, heating at least a portion of the particulate filter to a combustion temperature of the particulate matter, and introducing hydrocarbon fuel to the particulate filter. The hydrocarbon fuel facilitates combustion of the particulate matter to regenerate the particulate filter.

  4. Man-made respirable-sized organic fibers: what do we know about their toxicological profiles?

    Warheit, D B; Reed, K L; Webb, T R


    Man-made organic fibers (MMOFs) have been manufactured for over 50 years. Until recently, there have been few concerns raised regarding the safety of organic fiber dusts. This is due, in large part, to the perception that the dimensions of most, if not all, of these products were too large to be inhaled into the distal lungs of workers, i.e., were considered to be nonrespirable. A brief review of some of the issues related to organic fiber toxicology is presented herein. Some of the organic fiber-types used in commerce are identified and some fundamental tenets of fiber toxicology are discussed. In addition, the European Union, in their recent consideration for banning chrysotile asbestos fibers, evaluated some organic fiber substitutes and compared them to the hazards of asbestos. A brief review of their conclusions is described below. Finally, the results of some recent studies assessing the mechanisms of biodegradability of para-aramid respirable-sized, fiber-shaped particulates (RFP) are presented. Para-aramid (p-aramid) RFP are the most extensively-studied respirable organic fiber-type and RFP is the new term which describes respirable-sized organic fibers (ECETOC, 1996) (1). The results of these studies provide clues regarding the mechanism(s) of p-aramid RFP shortening in the lungs of exposed animals, and may be relevant for humans.

  5. Ammonium excretion and oxygen respiration of tropical copepods and euphausiids exposed to oxygen minimum zone conditions

    Kiko, Rainer; Hauss, Helena; Buchholz, Friedrich; Melzner, Frank


    Calanoid copepods and euphausiids are key components of marine zooplankton communities worldwide. Most euphausiids and several copepod species perform diel vertical migrations (DVMs) that contribute to the export of particulate and dissolved matter to midwater depths. In vast areas of the global ocean, and in particular in the eastern tropical Atlantic and Pacific, the daytime distribution depth of many migrating organisms corresponds to the core of the oxygen minimum zone (OMZ). At depth, the animals experience reduced temperature and oxygen partial pressure (pO2) and an increased carbon dioxide partial pressure (pCO2) compared to their near-surface nighttime habitat. Although it is well known that low oxygen levels can inhibit respiratory activity, the respiration response of tropical copepods and euphausiids to relevant pCO2, pO2, and temperature conditions remains poorly parameterized. Further, the regulation of ammonium excretion at OMZ conditions is generally not well understood. It was recently estimated that DVM-mediated ammonium supply could fuel bacterial anaerobic ammonium oxidation - a major loss process for fixed nitrogen in the ocean considerably. These estimates were based on the implicit assumption that hypoxia or anoxia in combination with hypercapnia (elevated pCO2) does not result in a down-regulation of ammonium excretion. We exposed calanoid copepods from the Eastern Tropical North Atlantic (ETNA; Undinula vulgaris and Pleuromamma abdominalis) and euphausiids from the Eastern Tropical South Pacific (ETSP; Euphausia mucronata) and the ETNA (Euphausia gibboides) to different temperatures, carbon dioxide and oxygen levels to study their survival, respiration and excretion rates at these conditions. An increase in temperature by 10 °C led to an approximately 2-fold increase of the respiration and excretion rates of U. vulgaris (Q10, respiration = 1.4; Q10, NH4-excretion = 1.6), P. abdominalis (Q10, respiration = 2.0; Q10, NH4-excretion = 2.4) and

  6. Soil respiration partition and its components in the total agro-ecosystem respiration

    Delogu, Emilie; LeDantec, Valerie; Mordelet, Patrick; Buysse, Pauline; Aubinet, Marc; Pattey, Elizabeth; Mary, Bruno


    Close to 15% of the Earth's terrestrial surface is used for cropland. In the context of global warming, and acknowledged by the Kyoto Protocol, agricultural soils could be a significant sink for atmospheric CO2. Understanding the factors influencing carbon fluxes of agricultural soils is essential for implementing efficient mitigation practices. Most of the soil respiration modeling studies was carried out in forest ecosystems, but only a few was carried out in agricultural ecosystems. In the study, we evaluated simple formalisms to model soil respiration using wheat data from four contrasting geographical mi-latitude regions. Soil respiration were measured in three winter wheat fields at Lamasquère (43°49'N, 01°23'E, 2007) and Auradé (43°54'N, 01°10'E, 2008), South-West France and Lonzée (50°33'N, 4°44'E, 2007), Belgium, and in a spring wheat field at Ottawa (45°22'N, 75°43'W, 2007, 2011), Ontario, Canada. Manual closed chambers were used in the French sites. The Belgium and Canadian sites were equipped with automated closed chamber systems, which continuously collected 30-min soil respiration exchanges. All the sites were also equipped with eddy flux towers. When eddy flux data were collected over bare soil, the net ecosystem exchange (NEE) was equal to soil respiration exchange. These NEE data were used to validate the model. Different biotic and abiotic descriptors were used to model daily soil respiration and its heterotrophic and autotrophic components: soil temperature, soil relative humidity, Gross Primary Productivity (GPP), shoot biomass, crop height, with different formalisms. It was interesting to conclude that using biotic descriptors did not improve the performances of the model. In fact, a combination of abiotic descriptors (soil humidity and soil temperature) allowed significant model formalism to model soil respiration. The simple soil respiration model was used to calculate the heterotrophic and autotrophic source contributions to

  7. Management effects on European cropland respiration

    Eugster, W.; Moffat, A.; Ceschia, E.


    findings are based on all available CarboEurope IP eddy covariance flux measurements during a 4-year period (2004-2007). Detailed management information was available for 15 out of the 22 sites that contributed flux data, from which we compiled 30 types of management for European-scale comparison...... factors other than management alone are also important at a given site. Temperature is the climatic factor that showed best correlation with site-specific respiration fluxes. Therefore, the effect of temperature changes between the time periods before and after management were taken into account......Increases in respiration rates following management activities in croplands are considered a relevant anthropogenic source of CO2. In this paper, we quantify the impact of management events on cropland respiration fluxes of CO2 as they occur under current climate and management conditions. Our...

  8. Maintenance, endogeneous, respiration, lysis, decay and predation

    loosdrecht, Marc C. M. Van; Henze, Mogens


    In activated sludge processes an increased sludge age is associated with a decreased sludge production. This phenomenon is generally interpreted as a result of endogenous respiration processes. In the activated sludge models cell lysis (or decay) is incorporated. The lysis is modelled...... mechanism is microbiologically correct. The lysis/decay model mechanism is a strongly simplified representation of reality. This paper tries to review the processes grouped under endogenous respiration in activated sludge models. Mechanisms and processes such as maintenance, lysis, internal and external...... and maintenance processes. This conversion will in general be denoted as endogenous respiration. Based on the literature review the phenomena are discussed and organised, in order to create a working platform for discussing more detailed activated sludge models, one of which is being sketched. (C) 1999 IAWQ...

  9. The external respiration and gas exchange in space missions

    Baranov, V. M.; Tikhonov, M. A.; Kotov, A. N.

    both and its individual systems including an external respiration function. In this case, it should be remembered that the external respiration system has some physiological and morphological properties due to which the body systems are particularly subjected to environmental effects. Thus, according to figurative comparison by Evald Veible a contact area of the lungs with an external environment i.e. an alveolar surface is large and equaled approximately to tennis-court size, as the alveolocapillary membrane thickness is negligible and amounts to one fiftieth of a writing-paper sheet [1]. From this it follows that such a fine and highly organized structure must be extremely dependent upon any external exposures including gravitational ones since from the physical viewpoint of physics the lungs represent a quasiconical three-dimensional elastic body suspended in the thoracic cavity and in which there occur the gravity-induced internal tensions incrementing in a base-to-apices direction. As a result of these tensions, in the lungs various physical gradients: hydrostatic, pleural and transpulmonary pressures, pulmonary time constant, vertical gradient of the volume and structure of alveoli, etc. are developed.

  10. Experimental study on particulate materials collected by a concave of sea floor; Kaitei kubochi ni hoshusareru ryujobutsu ni kansuru jikkenteki kosatsu

    Hoshika, A.; Tanimoto, T. [Government Industrial Research Chugoku, Hiroshima (Japan)


    As one of the method of sea cleaning method, an idea where concave is dredged on the sea floor and suspended substances and polluted sediment particles are collected, is popular. In this research, simple experiment was carried out for collecting the materials by using a polyvinylchloride cylindrical vessel (50cm in diameter, 70cm in depth) set on the sea floor of Osaka Bay area and fundamental study about the quality of collected materials, collection effectiveness and so forth was carried out. Further, along with the collection experiment, measurement of degree of pollution and investigation of bottom laminar flow which is thought to be the direct outer force for particulate material movement were carried out in order to study the flow mechanism of particulate materials. As a result, with the setting of collection vessel, particulate materials about 9 times more than that of estimated natural sedimentation amount were collected. This corresponds to the 5% of the horizontal flux of suspended substances in the bottom layer water. Among the collected particulate materials, about 30% are suspended substances, about 70% are surface sediment substances. This kind of method, when combined suitably with the method for removing collected particulate materials, can be one of the effective method for the purification of polluted sediment materials. 8 refs., 9 figs., 3 tabs.

  11. The LIGO Suspended Optic Digital Control System

    Heefner, J W


    The original LIGO suspension control system [1] used analog circuitry to implement the closed loop damping required for local control of each the suspended optics. Recent developments in analog to digital converters (ADC), digital to analog converters (DAC), increased processor speed and performance, and the use of reflective memory have made a digital alternative possible. Such a control system would provide additional performance and flexibility that will be required for operation of the interferometers. This paper will describe the real-time digital servo control systems that have been designed, developed and implemented for the LIGO suspended optics. In addition, the paper will describe how the suspension controls have been integrated into the overall LIGO control and data acquisition systems [2].


    Jianjun ZHOU; Binliang LIN; Bingnan LIN


    This paper presents a rational basis to model the transport of suspended sediment. The looseboundary condition for 3D models and the adjustment coefficients for both the depth-integrated 2D and laterally integrated 1D models are treated comprehensively. A combination of Dirichlet and Neumann conditions is proposed as the loose-boundary condition. The adjustment coefficient for 2D models is obtained on the basis of the proposed boundary condition and analytical solutions developed for some simple cases of non-equilibrium transport of sediment in uniform flows. The adjustment coefficient for 1D models for natural rivers is further obtained from lateral integration. Comparisons with analytical solutions and a considerable amount of laboratory and prototype data show that mathematical models developed along the proposed line of attack would well simulate the transport of suspended sediment in practical problems.

  13. Electromechanically Tunable Suspended Optical Nano-antenna

    Chen, Kai; Razinskas, Gary; Feichtner, Thorsten; Grossmann, Swen; Christiansen, Silke; Hecht, Bert


    Coupling mechanical degrees of freedom with plasmonic resonances has potential applications in optomechanics, sensing, and active plasmonics. Here we demonstrate a suspended two-wire plasmonic nano-antenna acting like a nano-electrometer. The antenna wires are supported and electrically connected via thin leads without disturbing the antenna resonance. As a voltage is applied, equal charges are induced on both antenna wires. The resulting equilibrium between the repulsive Coulomb force and th...

  14. Current state of particulate matter research and management in Serbia (Introductory paper

    Milena Jovašević-Stojanović


    Full Text Available Particulate matter is the air pollutant that currently receives most attention from the atmospheric research community, the legislative authorities and the general public. Limiting particulate matter in the atmosphere which will result in significant benefits for human health, with associated positive economic consequences. Successful management of particulate matter requires scientific knowledge about particulate matter “from cradle to grave”, covering sources of particles, processes that govern their formation, composition, dispersion and fate in the atmosphere, as well as knowledge about human exposure and associated health and well being. Such knowledge allows to design and perform effective and efficient abatement measures and monitoring. This paper provides an introduction to the research and monitoring regarding particulate matter in Serbia. The contributions were first partly presented at the 2nd international workshop of the WeBIOPATR “Outdoor concentration, size distribution and composition of respirable particles in WB urban area” project in September 2009. This information provides context to the contributions in this number, and was part of the rationale of the project WeBIOPATR.

  15. Computing partial-shift respirator use periods

    Shotwell, H.P.; Caporossi, J.C.


    Airborne contaminant concentrations cannot always be reduced to desired levels even after the installation of feasible engineering controls. The industrial hygienist may have to recommend full-shift or partial-shift use of appropriate respirators to reduce exposures. The method described allows a recommendation to be made of the minimum period of time an exposed employee needs to use a repirator in order to reach the desired exposure level. The procedure is based on the calculation of time-weighted averages, using the upper confidence levels of air sampling data, and the respirator protection factors.

  16. BOREAS TE-2 Wood Respiration Data

    Ryan, Michael G.; Lavigne, Michael; Hall, Forrest G. (Editor); Papagno, Andrea (Editor)


    The BOREAS TE-2 team collected several data sets in support of its efforts to characterize and interpret information on the respiration of the foliage, roots, and wood of boreal vegetation. This data set contains measurements of wood respiration conducted in the NSA during the growing season of 1994. The data are stored in tabular ASCII files. The data files are available on a CD-ROM (see document number 20010000884), or from the Oak Ridge National Laboratory (ORNL) Distributed Active Archive Center (DAAC).

  17. BOREAS TE-2 Foliage Respiration Data

    Ryan, Michael G.; Hall, Forrest G. (Editor); Lavigne, Michael; Papagno, Andrea (Editor)


    The BOREAS TE-2 team collected several data sets in support of its efforts to characterize and interpret information on the respiration of the foliage, roots, and wood of boreal vegetation. This data set contains measurements of foliar respiration conducted in the NSA during the growing season of 1994. The data are stored in tabular ASCII files. The data files are available on a CD-ROM (see document number 20010000884), or from the Oak Ridge National Laboratory (ORNL) Distributed Active Archive Center (DAAC).

  18. BOREAS TE-2 Root Respiration Data

    Ryan, Michael G.; Lavigne, Michael; Hall, Forrest G. (Editor); Papagno, Andrea (Editor)


    The BOREAS TE-2 team collected several data sets in support of its efforts to characterize and interpret information on the respiration of the foliage, roots, and wood of boreal vegetation. This data set includes means of tree root respiration measurements on roots having diameters ranging from 0 to 2 mm conducted in the NSA during the growing season of 1994. The data are stored in tabular ASCII files. The data files are available on a CD-ROM (see document number 20010000884), or from the Oak Ridge National Laboratory (ORNL) Distributed Active Archive Center (DAAC).

  19. BOREAS TE-2 Continuous Wood Respiration Data

    Hall, Forrest G. (Editor); Papagno, Andrea (Editor); Ryan, Michael G.; Lavigne, Michael


    The BOREAS TE-2 team collected several data sets in support of its efforts to characterize and interpret information on the respiration of the foliage, roots, and wood of boreal vegetation. This data set contains measurements of wood respiration measured continuously (about once per hour) in the NSA during the growing season of 1994. The data are stored in tabular ASCII files. The data files are available on a CD-ROM (see document number 20010000884), or from the Oak Ridge National Laboratory (ORNL) Distributed Active Archive Center (DAAC).

  20. A novel optical scattering collection system for particulate monitoring applications

    Bernacki, B.E.; Miller, A.C. Jr. [Oak Ridge National Lab., TN (United States); Nuspliger, R.J. [Environmental Systems Corp., Knoxville, TN (United States)


    Light collecting systems often require radically different optical surfaces than those commonly found in optical imaging systems. An optical particulate monitor must probe a volume in emission stacks to obtain a good statistical distribution of suspended particles. However, ideal imaging systems map object planes into conjugate image planes and can probe only small volumes. The authors describe the design, fabrication and performance of a novel optical scattering collection system that exploits precision-engineered reflective conical surfaces (axicons) in a telescopic arrangement that maps a line in object space onto the detector plane in image space. Such non-spherical surfaces are nearly impossible to fabricate using traditional methods, but can readily be made using the deterministic method of single-point diamond turning. In addition to complex optical surfaces, single-point diamond turning also makes possible the precision engineering of reference surfaces useful for built-in alignment of multiple surfaces and rapid assembly of the finished system.

  1. Acoustic estimation of suspended sediment concentration

    朱维庆; 朱敏; 周忠来; 潘锋; 霍其增; 张向军


    In this paper, the acoustic estimation of suspended sediment concentration is discussed and two estimation methods of suspended sediment concentration are presented. The first method is curve fitting method, in which, according to the acoustic backscattering theory we assume that the fit-ting factor K1 (r) between the concentration M(r) obtained by acoustic observation and the concentra-tion M0(r) obtained by sampling water is a high order power function of distance r. Using least-square algorithm, we can determine the coefficients of the high order power function by minimizing the differ-ence between M(r) and M0(r) in the whole water profile. To the absorption coefficient of sound due to the suspension in water we do not give constraint in the first method. The second method is recur-sive fitting method, in which we take M0(r) as the conditions of initialization and decision and give ra-tional constraints to some parameters. The recursive process is stable. We analyzed the two methods with a lot of experimental data. The analytical results show that the estimate error of the first method is less than that of the second method and the latter can not only estimate the concentration of suspended sediment but also give the absorption coefficient of sound. Good results have been obtained with the two methods.

  2. Contribution of Root Respiration to Total Soil Respiration in a Cotton Field of Northwest China

    ZHAO Zhi-Min; ZHAO Cheng-Yi; Y.YILIHAMU; LI Ju-Yan; LI Jun


    To measure the contribution of root respiration (Rr) to total soil respiration (Rt) in arid cotton fields,eighteen plots,nine for girdling and nine control,were built in an arid cotton field in the Aksu National Experimental Station of Oasis Farmland Ecosystem,Xinjiang of China.Given the difference of soil respiration between girdled plots and non-girdled control plots,the components of soil respiration,root respiration (Rr) and respiration originating from decomposition (Rd) were divided.The temperature sensitivities of Rr and Rd were analyzed,respectively.The results showed that the average contribution of Rr to Rt in arid cotton field was about 32% during the study period.The temperature-response curve of Rr differed from that of Rd.The dynamic variation of Rd was more related to the change of soil temperature as compared to Rr.Rr and Rd had different responses to the variation of environment,and thus new models capable of differentiating between Rr and Rd are needed for evaluating the different factors controlling these two components of soil respiration in arid cotton field.

  3. Respiration the forgotten flux: new insights on ecosystem respiration and its global significance

    Ballantyne, Ashley


    There is strong evidence that most of the variability in the global carbon cycle is due to processes occurring in the terrestrial biosphere; however, identifying these processes is extremely challenging. The two largest fluxes in the global carbon cycle are gross primary productivity and total respiration of the terrestrial biosphere. Considerable research has focused on factors controlling primary productivity, but total respiration has received much less attention. Here results are shared indicating that much of the previously identified variability in the global carbon cycle is due to the temperature sensitivity of respiration in the tropics. Furthermore, the recent acceleration in net terrestrial carbon uptake is due to diminished respiration during the recent warming hiatus. Lastly, total soil respiration at the global scale is sensitive to precipitation and soil moisture. I hypothesize that this reflects the sensitivity of autotrophic respiration to precipitation and the sensitivity of heterotrophic respiration to soil moisture. I am seeking creative ways in which to experimentally test this hypothesis through experimental manipulation or model simulation.

  4. Study on submerged anaerobic membrane bioreactor (SAMBR) treating high suspended solids raw tannery wastewater for biogas production.

    Umaiyakunjaram, R; Shanmugam, P


    This study deals with the treatment of high suspended solids raw tannery wastewater using flat sheet Submerged Anaerobic Membrane (0.4μm) Bioreactor (SAMBR) acclimatized with hypersaline anaerobic seed sludge for recovering biogas. The treatability of SAMBR achieved higher CODremoval efficiency (90%) and biogas yield (0.160L.g(-1) CODremoved) coincided with high r(2) values between permeate flux and TSS (0.95), biogas and COD removed (0.96). The acidification of hypersaline influent wastewater by biogas mixing with high CO2, achieved quadruplet benefit of gas liquid and solid separation, in-situ pH and NH3 control, in-situ CH4 enrichment, and prevention of membrane fouling. The initial high VFA became stable as time elapsed reveals the hydrolysing ability of particulate COD into soluble COD and into biogas, confirms the suitability of SAMBR for high suspended solids tannery wastewater.

  5. Trace elements associated with atmospheric particulate matter in the Upper Hunter Valley, NSW, Australia

    Farhana, Biswas Karabi [Bangladesh Institute of Research and Rehabilitation in Diabetes, Endcrine and Metabolic Disorders (BIRDEM), Research Division, Dhaka (Bangladesh); Bridgman, Howard [University of Newcastle, Dept. of Geography and Environmental Science (Australia); McOrist, Gordon [Australian Nuclear Science and Technology Organization (ANSTO), Environment Division, Menai (Australia)


    Airbone particulate matter, both total suspended particulate (TSP) and PM{sub 10}, and soil samples from four sampling sites were collected in the Upper Hunter Valley in NSW, Australia in early 1999. This study aimed to measure relative amounts of particulates during this period, and identify associated trace elements and their potential sources. Particulates were analyzed for trace elements using Neutron Activation Analysis technique. Total concentrations ({mu}g m{sup -3}) of TSP and PM{sub 10} varied within 7-135 and 4-19, respectively, among sampling sites. Mean concentrations (ng m{sup -3}) of iron, barium, zinc, lanthanum, bromine, chromium, rubidium, neodymium, cobalt, hafnium, cerium, thorium, uranium, scandium and cesium varied within 2042-2867, 529-1500, 28-40, 5.45-11.44, 5.3-20.6, 10.4-12.7, 4.14-11.56, 5.4-8.1, 1.16-1.98, 1.76-2.17, 0.71-3.9, 0.21-0.50, 0.29-0.84, 0.28-1.23, and 0.18-0.30, respectively. Significant correlation between sites for many elements suggested some common source(s) of some elements. The enrichment levels of the trace elements identified some crustal materials as a predominant source of particulate matter. (author)

  6. Hydrodynamic controls on respiration in the Amazon River and the importance of particle interactions on organic matter decomposition

    Ward, N. D.; Sawakuchi, H. O.; Bianchi, T. S.; Gagne-Maynard, W.; Neu, V.; da Silva, D. F.; Diniz, J. E. D. M.; de Matos Valerio, A.; Cunha, A. C.; Brito, D. C.; da Silva, R.; Krusche, A. V.; Richey, J. E.; Keil, R. G.


    Microbial decomposition of terrestrial and aquatic organic matter (OM) drives an evasive CO2gas flux from the world's inland waters comparable to the amount of anthropogenic carbon absorbed by the terrestrial biosphere. However, the physical factors regulating aquatic respiration rates are not well understood and traditional respiration experiments have not satisfactorily represented the turbulent conditions that microbes experience in large rivers. We hypothesize that interactions between the OM/microbes associated with particles and their free-living/dissolved counterparts such as exoenzyme activity, cometabolism, and priming effects are a critical factor controlling respiration rates. River velocity is directly linked to the abundance of particles that remain suspended, and as such, should regulate respiration accordingly. This study examines the influence of river velocity on aquatic respiration based on experiments performed in the lower Amazon River with stationary and rotating incubation chambers equipped with integrated O2 probes to monitor O2 drawdown in real-time. For all experiments performed there was a robust positive correlation between the rate at which chambers were spun and the measured respiration rate (r2 values ranged from 0.76 to 1.00). This relationship was then used to normalize respiration rates to instantaneous measurements of river velocity across each river channel. Whereas average respiration rates measured in traditional BOD bottles could only account for 12 ± 7% of the annual average CO2 outgassing rate measured along the lower Amazon River mainstem, respiration rates based on chambers spinning at 0.22 m s-1, 0.66 m s-1, and velocity-normalized calculations could account for 64 ± 22%, 104 ± 36%, and 130 ± 62% of the CO2 outgassing rate, respectively (average river velocity along the lower Amazon River was 0.98 ± 0.42 m s-1). During each sampling campaign there was a positive correlation with river velocity and in situ CO2

  7. Particulate heavy metal transport in the lower Paraíba do Sul River basin, southeastern, Brazil

    Salomão, M. S. M. B.; Molisani, M. M.; Ovalle, A. R. C.; Rezende, C. E.; Lacerda, L. D.; Carvalho, C. E. V.


    In the present study an attempt has been made to calculate the mass transfers of suspended particulate matter and associated heavy metal within the lower portion of the Paraíba do Sul River drainage basin and the contribution of its tributaries. The highest metal loads were related with the highest water flows and, consequently, with the highest suspended particulate matter loads, which increased both by surface runoff and sediment resuspension. The highest flow month for the total transported load contributed between 34 and 66% of the total metal transported per year. The total load transported during the entire rainy season ranges from 82 to 93% of the total transported load. The importance of the tributary input for the total transported load of the Paraíba do Sul River was generally lower than 10%, although in some months, when the Paraíba do Sul River had low water discharge and strong local rain occurred, this increased upto 40%.

  8. Sulfide-inhibition of mitochondrial respiration at very low oxygen concentrations.

    Matallo, J; Vogt, J; McCook, O; Wachter, U; Tillmans, F; Groeger, M; Szabo, C; Georgieff, M; Radermacher, P; Calzia, E


    Our aim was to study the ability of an immortalized cell line (AMJ2-C11) to sustain aerobic cell respiration at decreasing oxygen concentrations under continuous sulfide exposure. We assumed that the rate of elimination of sulfide through the pathway linked to the mitochondrial respiratory chain and therefore operating under aerobic conditions, should decrease with limiting oxygen concentrations. Thus, sulfide's inhibition of cellular respiration would occur faster under continuous sulfide exposure when the oxygen concentration is in the very low range. The experiments were performed with an O2K-oxygraph (Oroboros Instruments) by suspending 0.5-1×10(6) cells in 2 ml of continuously stirred respiration medium at 37 °C and calculating the oxygen flux (JO2) as the negative derivative of the oxygen concentration in the medium. The cells were studied in two different metabolic states, namely under normal physiologic respiration (1) and after uncoupling of mitochondrial respiration (2). Oxygen concentration was controlled by means of a titration-injection pump, resulting in average concentration values of 0.73±0.05 μM, 3.1±0.2 μM, and 6.2±0.2 μM. Simultaneously we injected a 2 mM Na2S solution at a continuous rate of 10 μl/s in order to quantify the titration-time required to reduce the JO2 to 50% of the initial respiratory activity. Under the lowest oxygen concentration this effect was achieved after 3.5 [0.3;3.5] and 11.7 [6.2;21.2]min in the uncoupled and coupled state, respectively. This time was statistically significantly shorter when compared to the intermediate and the highest O2 concentrations tested, which yielded values of 24.6 [15.5;28.1]min (coupled) and 35.9 [27.4;59.2]min (uncoupled), as well as 42.4 [27.5;42.4]min (coupled) and 51.5 [46.4;51.7]min (uncoupled). All data are medians [25%, and 75% percentiles]. Our results confirm that the onset of inhibition of cell respiration by sulfide occurs earlier under a continuous exposure when approaching

  9. Suspended sediment load and mechanical erosion in the Senegal Basin — Estimation of the surface runoff concentration and relative contributions of channel and slope erosion

    Kattan, Z.; Gac, J. Y.; Probst, J. L.


    The main purpose of this paper is to propose a method to better understand the suspended sediment dynamics in the Senegal Basin, and the behaviour of the river particulate load at Bakel gauging station (218,000 km 2) during the period 1979-1984. The method is based on the estimation of surface discharge using a simple hydrological model which allows separation of the different flow components of the annual hydrograph. Then the suspended sediment loads can be correlated with the surface discharge. During the study period, the mean annual flow (330 m 3s -1) represented only 46% of the mean long-term flow (1903-1984), and the mean yearly particulate load carried by the Senegal River was about 1.9 million tons. Two approaches are used to estimate the different contributions to the river's suspended sediment transport. The main contribution originates from slope erosion, which supplies 50-80% of the total sediment transport and the second originates from channel erosion. The suspended sediment concentration in the surface runoff, primarily calculated by a global annual method, ranges from 0.9 to 1.6 gl -1 and averages 1.3 gl -1. After correction for channel erosion input, this concentration is reduced to 1.1 gl -1.

  10. Respiration in Heterotrophic Unicellular Eukaryotic Organisms

    Fenchel, Tom


    about 10% and mitochondria are predominantly found close to the outer membrane. The results predict that for small and medium sized protozoa maximum respiration rates should be proportional to cell volume (scaling exponent ≈1) and access to intracellular O2 is not limiting except at very low ambient O2...

  11. Estimating Canopy Dark Respiration for Crop Models

    Monje Mejia, Oscar Alberto


    Crop production is obtained from accurate estimates of daily carbon gain.Canopy gross photosynthesis (Pgross) can be estimated from biochemical models of photosynthesis using sun and shaded leaf portions and the amount of intercepted photosyntheticallyactive radiation (PAR).In turn, canopy daily net carbon gain can be estimated from canopy daily gross photosynthesis when canopy dark respiration (Rd) is known.

  12. Respiration patterns of resting wasps (Vespula sp.).

    Käfer, Helmut; Kovac, Helmut; Stabentheiner, Anton


    We investigated the respiration patterns of wasps (Vespula sp.) in their viable temperature range (2.9-42.4°C) by measuring CO2 production and locomotor and endothermic activity. Wasps showed cycles of an interburst-burst type at low ambient temperatures (Ta31°C, CO2 emission became cyclic. With rising Ta they enhanced CO2-emission primarily by an exponential increase in respiration frequency, from 2.6 mHz at 4.7°C to 74 mHz at 39.7°C. In the same range of Ta CO2 release per cycle decreased from 38.9 to 26.4 μl g(-1)cycle(-1). A comparison of wasps with other insects showed that they are among the insects with a low respiratory frequency at a given resting metabolic rate (RMR), and a relatively flat increase of respiratory frequency with RMR. CO2 emission was always accompanied by abdominal respiration movements in all open phases and in 71.4% of the flutter phases, often accompanied by body movements. Results suggest that resting wasps gain their highly efficient gas exchange to a considerable extent via the length and type of respiration movements.

  13. Do Tree Stems Recapture Respired CO2?

    Hilman, B.; Angert, A.


    Tree stem respiration is an important, yet not well understood, component of the terrestrial carbon cycle. Predicting how trees as whole organisms respond to changes in climate and atmospheric CO2 requires understanding of the variability in the fraction of assimilated carbon allocated to respiration, versus the allocation to growth, damage repair, and to rhizosphere symbionts. Here we used the ratio of CO2 efflux/O2 influx (Apparent Respiratory Quotient, ARQ) to study stem respiration. The ARQ in trees stems is predicted to be 1.0, as a result of carbohydrates metabolism. Lower than 1.0 ARQ values may indicate a local assimilation of respired CO2, or dissolution and transport of CO2 in the xylem stream. We measured stems ARQ in 16 tree species at tropical, Mediterranean and temperate ecosystems using stem chambers and in-vitro incubations. The CO2 and O2 were measured by a system we developed, which is based on an IRGA and a Fuel-cell O2 analyzer (Hilman and Angert 2016). We found typical values of ARQ in the range of 0.4-0.8. Since incubations of detach stem tissues yielded similar ARQ values, and since the influence of natural variations in the transpiration stream on ARQ was found to be small, we conclude that the removal of the respired CO2 is not via dissolution in the xylem stream. Using 13C labeling, dark fixation of stem tissues was detected, which is most probably phosphoenolpyruvate carboxylase (PEPC) mediated. Hence, we suggest that in-stem dark fixation of respired CO2 to organic acids (e.g. malate) affects the outgoing efflux. Further research should determine if these organic acids are transported to the canopy, stored in the stem, or transported to the roots to serve as exudates. Hilman B, Angert A (2016) Measuring the ratio of CO2 efflux to O2 influx in tree stem respiration. Tree Physiol 2016, doi: 10.1093/treephys/tpw057

  14. Toward a general evaluation model for soil respiration (GEMSR)


    Soil respiration is an important component of terrestrial carbon budget. Its accurate evaluation is es- sential to the study of terrestrial carbon source/sink. Studies on soil respiration at present mostly focus on the temporal variations and the controlling factors of soil respiration, but its spatial variations and controlling factors draw less attention. Moreover, the evaluation models for soil respiration at present include only the effects of water and heat factors, while the biological and soil factors controlling soil respiration and their interactions with water and heat factors have not been considered yet. These models are not able to accurately evaluate soil respiration in different vegetation/terrestrial ecosystems at different temporal and spatial scales. Thus, a general evaluation model for soil respiration (GEMSR) including the interacting meteorological (water and heat factors), soil nutrient and biological factors is suggested in this paper, and the basic procedure developing GEMSR and the research tasks of soil respiration in the future are also discussed.

  15. Toward a general evaluation model for soil respiration (GEMSR)

    ZHOU GuangSheng; JIA BingRui; HAN GuangXuan; ZHOU Li


    Soil respiration is an important component of terrestrial carbon budget. Its accurate evaluation is essential to the study of terrestrial carbon source/sink. Studies on soil respiration at present mostly focus on the temporal variations and the controlling factors of soil respiration, but its spatial variations and controlling factors draw less attention. Moreover, the evaluation models for soil respiration at present include only the effects of water and heat factors, while the biological and soil factors controlling soil respiration and their interactions with water and heat factors have not been considered yet. These models are not able to accurately evaluate soil respiration in different vegetation/terrestrial ecosystems at different temporal and spatial scales. Thus, a general evaluation model for soil respiration (GEMSR)including the interacting meteorological (water and heat factors), soil nutrient and biological factors is suggested in this paper, and the basic procedure developing GEMSR and the research tasks of soil respiration in the future are also discussed.

  16. Metabolic interactions between methanogenic consortia and anaerobic respiring bacteria

    Stams, A.J.; Oude Elferink, S.J.; Westermann, Peter


    Most types of anaerobic respiration are able to outcompete methanogenic consortia for common substrates if the respective electron acceptors are present in sufficient amounts. Furthermore, several products or intermediate compounds formed by anaerobic respiring bacteria are toxic to methanogenic...

  17. PM 2.5 Airborne Particulates Near Frac Sand Operations.

    Walters, Kristin; Jacobson, Jeron; Kroening, Zachary; Pierce, Crispin


    The rapid growth of hydraulic fracturing for oil and gas extraction in the U.S. has led to 135 active "frac" sand mines, processing plants, and rail transfer stations in Wisconsin. Potential environmental health risks include increased truck traffic, noise, ecosystem loss, and groundwater, light, and air pollution. Emitted air contaminants include fine particulate matter (PM2.5) and respirable crystalline silica. Inhalation of fine dust particles causes increased mortality, cardiovascular disease, lung disease, and lung cancer. In the authors' pilot study, use of a filter-based ambient particulate monitor found PM2.5 levels of 5.82-50.8 µg/m3 in six 24-hour samples around frac sand mines and processing sites. Enforcement of the existing U.S. Environmental Protection Agency annual PM2.5 standard of 12 µg/m3 is likely to protect the public from silica exposure risks as well. PM2.5 monitoring around frac sand sites is needed to ensure regulatory compliance, inform nearby communities, and protect public health.

  18. Particulate face masks for protection against airborne pathogens - one size does not fit all: an observational study.

    Winter, Susan; Thomas, Jane H; Stephens, Dianne P; Davis, Joshua S


    To determine the proportion of hospital staff who pass fit tests with each of three commonly used particulate face masks, and factors influencing preference and fit test results. Observational study. 50 healthy hospital staff volunteers in an 18-bed general intensive care unit in an Australian teaching hospital. Participants were administered a questionnaire about mask use and their preferred mask and underwent qualitative fit-testing with each of three different particulate masks: Kimberly-Clark Tecnol FluidShield N95 particulate filter respirator (KC), 3M Flat Fold 9320 particulate respirator and 3M 8822 particulate respirator with exhalation valve. Participants who failed fittesting were trained in correct mask donning, and fittesting was repeated. Proportion of participants who passed the fit test for each mask and the effect of training. The proportion of participants who passed a fit test was low for all three masks tested (KC, 16%; flat fold, 28%; and valved, 34%). Rates improved after training: the first mask tested fitted in 18% of participants pre-training and 40% post-training (P = 0.02). None of the masks fitted for 28% of participants. There were no significant predictors of fit-test results. A large proportion of individuals failed a fit test with any given mask, and we were not able to identify any factors that predicted mask fit in individuals. Training on mask use improved the rates of adequate fit. Hospitals should carry a range of P2 masks, and should conduct systematic P2 mask training and fit-testing programs for all staff potentially exposed to airborne pathogens.

  19. CDC WONDER: Daily Fine Particulate Matter

    U.S. Department of Health & Human Services — The Daily Fine Particulate Matter data available on CDC WONDER are geographically aggregated daily measures of fine particulate matter in the outdoor air, spanning...

  20. CDC WONDER: Daily Fine Particulate Matter

    U.S. Department of Health & Human Services — The Daily Fine Particulate Matter data available on CDC WONDER are geographically aggregated daily measures of fine particulate matter in the outdoor air, spanning...

  1. 30 CFR 57.5075 - Diesel particulate records.


    ..., Radiation, Physical Agents, and Diesel Particulate Matter Diesel Particulate Matter-Underground Only § 57.5075 Diesel particulate records. (a) The table entitled “Diesel Particulate Matter Recordkeeping...

  2. Distribution of some chemical elements between dissolved and particulate phases in the ocean. Research period: August 1, 1975--July 31, 1976. [Fallout /sup 210/Po and /sup 210/Pb diffusion in oceans


    Progress is reported on studies on the distributions of fallout /sup 210/Pb and /sup 210/Po in dissolved and particulate states in the Gulf of Maine and a transect of the equatorial North Atlantic Ocean. The ratio of /sup 210/Pb//sup 226/Ra and /sup 210/Po//sup 210/Pb in seawater and suspended particulate matter in samples collected from 10 stations in the tropical and eastern North Atlantic and two stations in the Pacific was also determined. (CH)

  3. Chlor-alkali industrial contamination and riverine transport of mercury: Distribution and partitioning of mercury between water, suspended matter, and bottom sediment of the Thur River, France

    Hissler, Christophe [Institut National Polytechnique (INP), Ecole Nationale Superieure Agronomique de Toulouse (ENSAT), Laboratoire Agronomie Environnement Ecotoxicologie - AEE, Avenue de l' Agrobiopole, BP 32 607, Auzeville-Tolosane, 31326 Castanet-Tolosan Cedex (France)]. E-mail:; Probst, Jean-Luc [Institut National Polytechnique (INP), Ecole Nationale Superieure Agronomique de Toulouse (ENSAT), Laboratoire Agronomie Environnement Ecotoxicologie - AEE, Avenue de l' Agrobiopole, BP 32 607, Auzeville-Tolosane, 31326 Castanet-Tolosan Cedex (France)]. E-mail:


    Total dissolved and total particulate Hg mass balances were estimated during one hydrological period (July 2001-June 2002) in the Thur River basin, which is heavily polluted by chlor-alkali industrial activity. The seasonal variations of the Hg dynamics in the aquatic environment were assessed using total Hg concentrations in bottom sediment and suspended matter, and total and reactive dissolved Hg concentrations in the water. The impact of the chlor-alkali plant (CAP) remains the largest concern for Hg contamination of this river system. Upstream from the CAP, the Hg partitioning between dissolved and particulate phases was principally controlled by the dissolved fraction due to snow melting during spring high flow, while during low flow, Hg was primarily adsorbed onto particulates. Downstream from the CAP, the Hg partitioning is controlled by the concentration of dissolved organic and inorganic ligands and by the total suspended sediment (TSS) concentrations. Nevertheless, the particulate fluxes were five times higher than the dissolved ones. Most of the total annual flux of Hg supplied by the CAP to the river is transported to the outlet of the catchment (total Hg flux: 70 {mu}g m{sup -2} a{sup -1}). Downstream from the CAP, the bottom sediment, mainly composed of coarse sediment (>63 {mu}m) and depleted in organic matter, has a weak capacity to trap Hg in the river channel and the stock of Hg is low (4 mg m{sup -2}) showing that the residence time of Hg in this river is short.

  4. Atmospheric particulate mercury in Lhasa city, Tibetan Plateau

    Huang, Jie; Kang, Shichang; Guo, Junming; Zhang, Qianggong; Cong, Zhiyuan; Sillanpää, Mika; Zhang, Guoshuai; Sun, Shiwei; Tripathee, Lekhendra


    In an effort to understand the biogeochemical cycling and seasonal characteristics of atmospheric Hg, a total of 80 daily sampled total suspended particulates were collected at Lhasa, the largest city of Tibet, from April 2013 to August 2014 for particulate-bound Hg (HgP) analysis. Daily concentrations of atmospheric HgP ranged from 61.2 to 831 pg m-3 with an average of 224 pg m-3, which were unexpectedly comparable to those measured in most of the Chinese metropolises. Both the daily/monthly average HgP concentrations were slightly but not significantly higher during the non-monsoon season than during the monsoon season. Together with the fact that there was lack of significant relationship between HgP concentration and most meteorological parameters, no significant and distinct pattern for the seasonal characteristics of atmospheric HgP could be mainly attributed to the almost equal emission strength of two principal anthropogenic Hg sources (i.e., industrial emission sources during the non-monsoon season, and vehicular traffic and religious sources during the monsoon season). Moreover, the HgP dry deposition rate was estimated to be 35.3 μg m-2 yr-1 by using a theoretical model, which was significantly higher than those Hg wet fluxes. The elevated deposition rate implied that dry deposition may play an important role in the biogeochemical Hg cycling over the Tibetan Plateau.

  5. Direct measurement of riverine particulate organic carbon age structure

    Rosenheim, Brad E.; Galy, Valier


    Carbon cycling studies focusing on transport and transformation of terrigenous carbon sources toward marine sedimentary sinks necessitate separation of particulate organic carbon (OC) derived from many different sources and integrated by river systems. Much progress has been made on isolating and characterizing young biologically-formed OC that is still chemically intact, however quantification and characterization of old, refractory rock-bound OC has remained troublesome. Quantification of both endmembers of riverine OC is important to constrain exchanges linking biologic and geologic carbon cycles and regulating atmospheric CO2 and O2. Here, we constrain petrogenic OC proportions in suspended sediment from the headwaters of the Ganges River in Nepal through direct measurement using ramped pyrolysis radiocarbon analysis. The unique results apportion the biospheric and petrogenic fractions of bulk particulate OC and characterize biospheric OC residence time. Compared to the same treatment of POC from the lower Mississippi-Atchafalaya River system, contrast in age spectra of the Ganges tributary samples illustrates the difference between small mountainous river systems and large integrative ones in terms of the global carbon cycle.

  6. Characterization of Urban Runoff Pollution between Dissolved and Particulate Phases

    Zhang Wei


    Full Text Available To develop urban stormwater management effectively, characterization of urban runoff pollution between dissolved and particulate phases was studied by 12 rainfall events monitored for five typical urban catchments. The average event mean concentration (AEMC of runoff pollutants in different phases was evaluated. The AEMC values of runoff pollutants in different phases from urban roads were higher than the ones from urban roofs. The proportions of total dissolved solids, total dissolved nitrogen, and total dissolved phosphorus in total ones for all the catchments were 26.19%–30.91%, 83.29%–90.51%, and 61.54–68.09%, respectively. During rainfall events, the pollutant concentration at the initial stage of rainfall was high and then sharply decreased to a low value. Affected by catchments characterization and rainfall distribution, the highest concentration of road pollutants might appear in the later period of rainfall. Strong correlations were also found among runoffs pollutants in different phases. Total suspended solid could be considered as a surrogate for particulate matters in both road and roof runoff, while dissolved chemical oxygen demand could be regarded as a surrogate for dissolved matters in roof runoff.

  7. Interaction Between DEHP and Particulate in a Eutrophic Lake

    迟杰; 刘华; 季民


    Characteristics of interaction between di-2-ethylhexyl phthalate(DEHP) and particulate in a eutrophic lake were studied in this paper. DEHP concentrations ranged from 89.9 to 247 μg/L with an average value of 146 μg/L in subsurface water (SSW) samples, and from 82.0 to 390 μg/L with an average value of 211 μg/L in water surface microlayer (SM) samples. The results indicate that there was only a weak correlation between the DEHP concentrations and suspended particulate material(SPM) concentrations in both SSW and SM, while the significant correlation between DEHP concentrations and chlorophyll a concentrations was found, which suggestes that DEHP was principally bound to phytoplankton in the eutrophic lake. Correlation between DEHP concentrations and total phosphor (TP) concentrations was also found in this investigation.Enrichment factors (EF) of DEHP in SM were in the range of 0.85 to 2.12 with an average value of 1.35. DEHP EFs were significantly related to the enrichment of chlorophyll a in SM. The results suggest that the enrichment of DEHP in SM of this eutrophic lake was mainly due to DEHP accumulation in phytoplankton and was controlled by distribution of phytoplankton between SM and SSW.

  8. Influence of microorganism content in suspended particles on the particle-water partitioning of mercury in semi-enclosed coastal waters.

    Jang, Jiyi; Kim, Hyunji; Han, Seunghee


    It is known that particle scavenging of mercury (Hg) can be affected by the abundance of particulate organic matter in coastal waters. However, the role of living organic particles in Hg scavenging is not yet completely understood. In this study, we hypothesized that an abundance of living organic particles (i.e., phytoplankton and bacteria) would influence the particle-water partitioning of Hg in coastal waters. Surface seawater samples were collected from eight stations in Gwangyang Bay, Korea, in three seasons (November 2009, April 2010, and October 2010) for the determination of concentrations of suspended particulate matter (including chlorophyll-a and bacteria), and Hg in unfiltered and filtered waters. We found that more Hg partitioned toward particulate matter when phytoplankton biomass, indicated from the chlorophyll-a concentration in a particle, was higher. In the low algal season, when [chlorophyll-a]marine food chains.

  9. Particulate matter and preterm birth

    Particulate matter (PM) has been variably associated with preterm birth (PTB) (gestation <37 weeks), but the role played by specific chemical components of PM has been little studied. We examined the association between ambient PM <2.5 micrometers in aerodynamic diameter (PM2.S) ...

  10. Transport phenomena in particulate systems

    Freire, José Teixeira; Ferreira, Maria do Carmo


    This volume spans 10 chapters covering different aspects of transport phenomena including fixed and fluidized systems, spouted beds, electrochemical and wastewater treatment reactors. This e-book will be valuable for students, engineers and researchers aiming to keep updated on the latest developments on particulate systems.

  11. Particulate matter and preterm birth

    Particulate matter (PM) has been variably associated with preterm birth (PTB) (gestation <37 weeks), but the role played by specific chemical components of PM has been little studied. We examined the association between ambient PM <2.5 micrometers in aerodynamic diameter (PM2.S) ...

  12. Particulate Matter: a closer look

    Buijsman E; Beck JP; Bree L van; Cassee FR; Koelemeijer RBA; Matthijsen J; Thomas R; Wieringa K; LED; MGO


    The summary in booklet form 'Fijn stof nader bekeken' (Particulate Matter: a closer look) , published in Dutch by the Netherlands Environmental Assessment Agency (MNP) and the Environment and Safety Division of the National Institute for Public Health and the Environment (RIVM), has been designed to

  13. [Endogenous respiration process analysis of heterotrophic biomass and autotrophic biomass based on respiration map ].

    Li, Zhi-hua; Bai, Xu-li; Zhang, Qin; Liu, Yi; He, Chun-bo


    The endogenous process is an important metabolic part of the activated sludge, and the understanding of this process is still unclear. Characteristics of endogenous respiration for heterotrophic bacteria and autotrophic nitrifiers were analyzed using respirogram. Results showed that both heterotrophic and autotrophic bacteria entered the stage of endogenous respiration at almost the same time, but heterotrophic bacteria first entered the stage of dormancy i. e. , they were easier to recover a higher proportion of biomass during the dormancy stage, indicating that heterotrophic bacteria exhibited strong environmental adaptability. Autotrophic bacteria were, however, quite different. This finding confirmed that autotrophic bacteria were more vulnerable from the viewpoint of endogenous respiration. In addition, the study also found that the increase of endogenous respiration rate ratio reflected the decreased sludge activity. And the proportion of endogenous respiration was an important parameter to characterize the activity of activated sludge, which can be used as a quantitative index for the health status of activated sludge. The findings further deepened the understanding of endogenous respiration process and provided a theoretical basis for the operation and management of wastewater treatment plants.

  14. 42 CFR 84.1134 - Respirator containers; minimum requirements.


    ... 42 Public Health 1 2010-10-01 2010-10-01 false Respirator containers; minimum requirements. 84..., Fume, and Mist; Pesticide; Paint Spray; Powered Air-Purifying High Efficiency Respirators and Combination Gas Masks § 84.1134 Respirator containers; minimum requirements. (a) Except as provided...

  15. 42 CFR 84.1156 - Pesticide respirators; performance requirements; general.


    ... resistance will be measured in the facepiece, mouthpiece, hood, or helmet of a pesticide respirator mounted... allowable resistance requirements for pesticide respirators are as follows: Maximum Resistance Type of... 42 Public Health 1 2010-10-01 2010-10-01 false Pesticide respirators; performance...

  16. Thermal adaptation of heterotrophic soil respiration in laboratory microcosms.

    Mark A. Bradford; Brian W. Watts; Christian A. Davies


    Respiration of heterotrophic microorganisms decomposing soil organic carbon releases carbon dioxide from soils to the atmosphere. In the short term, soil microbial respiration is strongly dependent on temperature. In the long term, the response of heterotrophic soil respiration to temperature is uncertain. However, following established evolutionary tradeoffs, mass-...

  17. Quantifying soil respiration at landscape scales. Chapter 11

    John B. Bradford; Michael G. Ryan


    Soil CO2, efflux, or soil respiration, represents a substantial component of carbon cycling in terrestrial ecosystems. Consequently, quantifying soil respiration over large areas and long time periods is an increasingly important goal. However, soil respiration rates vary dramatically in space and time in response to both environmental conditions...

  18. 21 CFR 892.1970 - Radiographic ECG/respirator synchronizer.


    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Radiographic ECG/respirator synchronizer. 892.1970... (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Diagnostic Devices § 892.1970 Radiographic ECG/respirator synchronizer. (a) Identification. A radiographic ECG/respirator synchronizer is a device intended to be used...

  19. Particulate nitrogen and phosphorus in the East China Sea and its adjacent Kuroshio waters and evaluation of budgets for the East China Sea Shelf

    Zuo, Jiulong; Song, Jinming; Yuan, Huamao; Li, Xuegang; Li, Ning; Duan, Liqin


    Nitrogen (N) and phosphorus (P) in suspended particles are important to the cycles of N and P in marine ecosystem. Suspended particles were collected from the East China Sea (ECS) and its adjacent Kuroshio waters to investigate the composing and distribution characteristics of particulate inorganic and organic nitrogen and phosphorus (PIN, PIP, PON and POP, respectively). The particulate N and P concentrations were fairly low in the Kuroshio water but much higher in the ECS water, especially in nearshore waters. PON and PIP were the dominant forms of particulate N and P, with an exception that POP was the major form of particulate P in the Kuroshio upper water. The regime of particulate N and P in the ECS was strongly influenced by riverine input, oceanic input, ocean current and photosynthesis. Among them, PON and POP were mainly from biogenic source, while PIN and PIP were originated from biogenic and external sources. And sedimentation, remineralization and resuspension were important influencing factors for the vertical distributions of particulate N and P. The budgets of particulate N and P for the ECS Shelf during rainy season (May-October) were also evaluated. The total particulate N and P (TPN and TPP) fluxes from oceanic input are respectively 10.99 and 2.49 times of those from riverine input. And oceanic input contains more POP, which is liable to be decomposed into phosphate, than riverine input. Furthermore, particulate nutrients fluxes from photosynthesis are the overriding source of total influxes for the ECS Shelf, accounting for 90.93% of TPN and 89.37% of TPP influxes. As for the photosynthetic fixed N and P, only 6.17% and 7.60% of them can reach the seafloor, while up to 87.73% and 60.06% of them are likely to be remineralized. The POP-rich oceanic input and the intensive photosynthesis and remineralization processes play important roles in the biogeochemical cycles of N and P in the ECS.

  20. Monitoring of suspended sediment in South Tyrol

    Nadalet, Rudi; Dinale, Roberto; Pernter, Martin; Maraldo, Luca; Peterlin, Dieter; Richter, Arnold; Comiti, Francesco


    In the context of the EU Water Framework Directive (WFD), which aims to achieve a good status of European water bodies, the Hydrographic Office of the Autonomous Province of Bolzano (Italy) extended in 2014 its institutional activities including the monitoring of suspended sediment in the river channel network. Currently, the only active monitoring station is on the Adige River at the gauging station of Ponte Adige near Bolzano (drainage area 2705 km2). The applied monitoring strategy and the data analysis concept are both based on the guidelines issued by the Austrian Federal Ministry of Agriculture, Forestry, Environment and Water Management (BMLFUW). The results indicates that the temporal variability strongly differs during the investigated period (2014-2015). In addition to the analysis of precipitation and water discharge, temperature and lightning activity were also included to better understand the sediment transport dynamics observed at the station. In summer 2015, the combination of constantly high daily temperature throughout the Adige basin (which drove intense glacier melting in the headwaters) with a high frequency of convective rainfall events (90% more than in 2014, obtained through lightning detection), led to an annual mass of transported suspended sediment of 260000 t. Interestingly, this value is similar to the one estimated for 2014 (300000 t), which was characterized by very different meteorological conditions (colder and wetter summer), but with the occurrence of an important flood in August, which transported half of the annual amount. Finally, we can conclude that the adopted monitoring strategy is applicable for institutional aims in terms of costs as well as in terms of time effort. During the next years, other stations for suspended sediment monitoring are planned to be installed in the Province to cover the most important river segments.

  1. Nanoscale atomic waveguides with suspended carbon nanotubes

    Peano, V; Kasper, A; Egger, R


    We propose an experimentally viable setup for the realization of one-dimensional ultracold atom gases in a nanoscale magnetic waveguide formed by single doubly-clamped suspended carbon nanotubes. We show that all common decoherence and atom loss mechanisms are small guaranteeing a stable operation of the trap. Since the extremely large current densities in carbon nanotubes are spatially homogeneous, our proposed architecture allows to overcome the problem of fragmentation of the atom cloud. Adding a second nanowire allows to create a double-well potential with a moderate tunneling barrier which is desired for tunneling and interference experiments with the advantage of tunneling distances being in the nanometer regime.

  2. Electronic structure of cobalt nanocrystals suspended inliquid

    Liu, Hongjian; Guo, Jinghua; Yin, Yadong; Augustsson, Andreas; Dong, Chungli; Nordgren, Joseph; Chang, Chinglin; Alivisatos, Paul; Thornton, Geoff; Ogletree, D. Frank; Requejo, Felix G.; de Groot, Frank; Salmeron, Miquel


    The electronic structure of cobalt nanocrystals suspended in liquid as a function of size has been investigated using in-situ x-ray absorption and emission spectroscopy. A sharp absorption peak associated with the ligand molecules is found that increases in intensity upon reducing the nanocrystal size. X-ray Raman features due to d-d and to charge-transfer excitations of ligand molecules are identified. The study reveals the local symmetry of the surface of {var_epsilon}-Co phase nanocrystals, which originates from a dynamic interaction between Co nanocrystals and surfactant + solvent molecules.

  3. Elastic properties of suspended black phosphorus nanosheets

    Wang, Jia-Ying; Li, Yang; Zhen, Liang; Xu, Cheng-Yan, E-mail: [School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001 (China); MOE Key Laboratory of Micro-systems and Micro-structures Manufacturing, Harbin Institute of Technology, Harbin 150080 (China); Zhan, Zhao-Yao [Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714 (China); Li, Tie [Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai 200050 (China)


    The mechanical properties of black phosphorus (BP) nanosheets suspended over circular holes were measured by an atomic force microscope nanoindentation method. The continuum mechanic model was introduced to calculate the elastic modulus and pretension of BP nanosheets with thicknesses ranging from 14.3 to 34 nm. Elastic modulus of BP nanosheets declines with thickness, and the maximum value is 276 ± 32.4 GPa. Besides, the effective strain of BP ranges from 8 to 17% with a breaking strength of 25 GPa. Our results show that BP nanosheets serve as a promising candidate for flexible electronic applications.

  4. Magnetic interaction of Janus magnetic particles suspended in a viscous fluid.

    Seong, Yujin; Kang, Tae Gon; Hulsen, Martien A; den Toonder, Jaap M J; Anderson, Patrick D


    We studied the magnetic interaction between circular Janus magnetic particles suspended in a Newtonian fluid under the influence of an externally applied uniform magnetic field. The particles are equally compartmentalized into paramagnetic and nonmagnetic sides. A direct numerical scheme is employed to solve the magnetic particulate flow in the Stokes flow regime. Upon applying the magnetic field, contrary to isotropic paramagnetic particles, a single Janus particle can rotate due to the magnetic torque created by the magnetic anisotropy of the particle. In a two-particle problem, the orientation of each particle is found to be an additional factor that affects the critical angle separating the nature of magnetic interaction. Using multiparticle problems, we show that the orientation of the particles has a significant influence on the dynamics of the particles, the fluid flow induced by the actuated particles, and the final conformation of the particles. Straight and staggered chain structures observed experimentally can be reproduced numerically in a multiple particle problem.

  5. A Seasonally Robust Empirical Algorithm to Retrieve Suspended Sediment Concentrations in the Scheldt River

    Dries Raymaekers


    Full Text Available A seasonally robust algorithm for the retrieval of Suspended Particulate Matter (SPM in the Scheldt River from hyperspectral images is presented. This algorithm can be applied without the need to simultaneously acquire samples (from vessels and pontoons. Especially in dynamic environments such as estuaries, this leads to a large reduction of costs, both in equipment and personnel. The algorithm was established empirically using in situ data of the water-leaving reflectance obtained over the tidal cycle during different seasons and different years. Different bands and band combinations were tested. Strong correlations were obtained for exponential relationships between band ratios and SPM concentration. The best performing relationships are validated using airborne hyperspectral data acquired in June 2005 and October 2007 at different moments in the tidal cycle. A band ratio algorithm (710 nm/596 nm was successfully applied to a hyperspectral AHS image of the Scheldt River to obtain an SPM concentration map.

  6. Radionuclide contents in suspended sediments in relation to flood types in the lower Rhone River

    Zebracki, Mathilde; Eyrolle-Boyer, Frederique; Antonelli, Christelle; Boullier, Vincent [IRSN / PRP-ENV, SESURE / LERCM, 13115 Saint-Paul-lez-Durance (France); De Vismes-Ott, Anne; Cagnat, Xavier [STEME / LMRE, 91400 Orsay (France)


    The aim of this work was to study the influence of watershed heterogeneity on the radionuclide contents of suspended particulate matter (SPM) in a large Mediterranean river. As the Rhone River catchment is characterized by a high climatic and geological heterogeneity, floods can be distinguished according to their geographic origins. Long-term time series of particles associated with radionuclides acquired in the framework of radiological surveillance provide a relevant dataset to investigate the variability of radionuclide contents. The SPM exported during Mediterranean floods differ from other floods as they display higher {sup 238}U and {sup 232}Th contents and the lowest activity ratio {sup 137}Cs/{sup (239+240)}Pu; these properties could be related to bedrock type and erosion process characteristics and/or to source term differentiation. (authors)

  7. Hydrogenase Activity of Mineral-Associated and Suspended Populations of Desulfovibrio desulfuricans Essex 6

    C.L. Reardon; T.S. Magnuson; E.S. Boyd; W.D. Leavitt; D.W. Reed; G.G. Geesey


    The interactions between sulfate-reducing microorganisms and iron oxides influence a number of important redox-sensitive biogeochemical processes including the formation of iron sulfides. Enzymes, such as hydrogenase which catalyze the reversible oxidation of molecular hydrogen, are known to mediate electron transfer to metals and may contribute to the formation and speciation of ferrous sulfides formed at the cell–mineral interface. In the present study, we compared the whole cell hydrogenase activity of Desulfovibrio desulfuricans strain Essex 6 growing as biofilms on hematite (hematite-associated) or as suspended populations using different metabolic pathways. Hematite-associated cells exhibited significantly greater hydrogenase activity than suspended populations during sulfate respiration but not during pyruvate fermentation. The enhanced activity of the hematite-associated, sulfate-grown cells appears to be dependent on iron availability rather than a general response to surface attachment since the activity of glass-associated cells did not differ from that of suspended populations. Hydrogenase activity of pyruvate-fermenting cells was stimulated by addition of iron as soluble Fe(II)Cl2 and, in the absence of added iron, both sulfate-reducing and pyruvate-fermenting cells displayed similar rates of hydrogenase activity. These data suggest that iron exerts a stronger influence on whole cell hydrogenase activity than either metabolic pathway or mode of growth. The location of hydrogenase to the cell envelope and the enhanced activity at the hematite surface in sulfate-reducing cells may influence the redox conditions that control the species of iron sulfides on the mineral surface.

  8. Residence time of suspended particles in the Garonne River (SW France): indications derived from Th-234, Be-7 and Pb-210

    Schmidt, Sabine; Saari, Hanna-Kaïsa


    Particulates that enter the ocean from rivers are the products of integrated basin-wide processes (soil erosion, sediment transport and deposition in watersheds). The fate of sediments in river is therefore challenging and generally analysed using hydrodynamics models. An alternative method relies on the use of fallout radioactive tracers to identify sediment source regions and/or to estimate suspended sediment age or the fraction of the suspended sediment recently eroded from the landscape. This work presents the application of naturally occurring radionuclides: Pb-210 (T1/2 = 22.3 years) and Be-7 (T1/2 = 53 days), both delivered by atmospheric fallout, and Th-234 (T1/2 = 24.1 days), to investigate residence times of particles in the lower Garonne River (South-West France). Th-234, produced continuously by decay of U-238, is widely used in marine sciences for studying particle dynamic on time-scales of days to weeks, but a major limitation to extend its application from the ocean to river is the activity (level, variability) of its parent, U-238, in contrast with the high and rather constant levels of oceanic uranium. The Garonne River has a watershed of 55 000 km2 with a mean discharge of 650 m3 s-1 (range: 12500 m3 s-1). It flows westward about 647 km from the Spanish Pyrenees, ending into the Gironde, its common estuary with the Dordogne River. To investigate suspended particle dynamic of the lower Garonne River, monthly samplings were performed from January 2006 to December 2007 at selected sites along this river system, including a site in its estuarine section. Dissolved and particulate activities of radionuclides were determined using a low-background, well-shaped gamma spectrometer. Additional data (river discharge, rain rate, suspended particulate concentrations) were also collected to better interpret radionuclide data. Whereas dissolved fractions are always negligible, particulate Th-234, Be-7 and Pb-210 activities present marked spatio

  9. Effect of ozonation on particulate matter in broiler houses.

    Li, Q; Wang, L; Oviedo-Rondón, E; Parnell, C B


    The effects of ozonation on particulate matter were studied on a commercial broiler farm. The farm consisted of 4 identical tunnel-ventilated houses (12.8×152.4 m): 2 houses were treated with O3 (maximum concentration 0.1 ppm) and the other 2 served as control units. The particle size distributions of total suspended particulate (TSP) samples from both control and treated houses were found to have very similar profiles with no statistical difference. The TSP concentrations were significantly higher in treated houses as compared with those in control houses, and the mean of the differences was 5.50 mg/m3. In both treated and control houses, there were substantial vertical TSP concentration gradients and the concentrations decreased with height. At broiler chicken height (0.28 m), TSP concentrations were 13±3 mg/m3 in control houses and 17±2 mg/m3 in treated houses. At human breathing height (1.55 m), TSP concentrations were 8±4 mg/m3 in control houses and 7±2 mg/m3 in treated houses. Particle phase NH4+ concentrations were higher in treated houses (ranging from 0.59 to 42.01 mg/m3 with mean=17.49 mg/m3) than in control houses (ranging from 0.34 to 13.55 mg/m3 with mean=4.42 mg/m3). The TSP samples from locations in the vicinity of the farm showed higher concentrations downwind than that upwind, but there were no significant differences observed among different ambient locations for TSP NH4+ concentrations. The results from this study did not show that direct application of ozonation technique has beneficial effects for particulate matter control in broiler houses.

  10. Particulate Matter Concentrations in East Oakland's High Street Corridor

    Lei, P.; Jackson, J.; Lewis, R.; Marigny, A.; Mitchell, J. D.; Nguyen, R.; Philips, B.; Randle, D.; Romero, D.; Spears, D.; Telles, C.; Weissman, D.


    Particulate matter (PM) is a complex mixture of small solid pieces and/or liquid droplets in the air. High concentrations of PM can pose a serious health hazard because inhalation can result in breathing problems and/or aggravate asthma. Long term exposure can increase the likelihood of respiratory problems like asthma and emphysema as well as cancer. The smaller the particles, the deeper they can get into the respiratory system. For this reason, the smallest particles, those smaller than 2.5 micrometers in diameter (PM2.5), are the most dangerous. PM2.5 is largely emitted from motor vehicles burning fuels that don't break down fully. Our research team investigated the levels of PM2.5 as well as particles smaller than 10 micrometers (PM10) and total suspended particulate (TSP) along the northeast-southwest trending High Street Corridor, near Fremont High School in East Oakland, California. Using the Aerocet 531 mass particle counter, team members walked through neighborhoods and along major roads within a 1 mile radius of Fremont High School. The Aerocet 531 recorded two minute average measurements of all the relevant PM sizes, which are reported in mg/m3. Measurements were consistently taken in the morning, between 8:30 and 11:30 am. Preliminary results indicate maximum readings of all PM sizes at sites that are in close proximity to a major freeway (Interstate-880). These results support our initial hypothesis that proximity to major roads and freeways, especially those with high diesel-fuel burning truck traffic, would be the primary factor affecting PM concentration levels. Preliminary median and maximum readings all suggest particulate matter levels below what the EPA would consider unhealthy or risky.

  11. Zinc toxicology following particulate inhalation

    Cooper Ross


    Full Text Available The current mini-review describes the toxic effects of zinc inhalation principally in the workplace and associated complications with breathing and respiration. The International Classification of Functioning, Disability and Health Criteria were used to specifically select articles. Most of the commercial production of zinc involves the galvanizing of iron and the manufacture of brass. The recommended daily allowance for adults is 15 mg zinc/day. Metal fume fever associated with inhalation of fumes of ZnO is characterized by fatigue, chills, fever, myalgias, cough, dyspnea, leukocytosis, thirst, metallic taste and salivation. ZnCl 2 inhalation results in edema in the alveolar surface and the protein therein the lavage fluid is elevated. Particular pathological changes associated with zinc intoxication include: pale mucous membranes; jaundice; numerous Heinz bodies; and marked anemia. Adequate ambient air monitors for permissible exposure limits, excellent ventilation and extraction systems, and approved respirators are all important in providing adequate protection.

  12. Technical Note: Particulate reactive oxygen species concentrations and their association with environmental conditions in an urban, subtropical climate

    S. S. Khurshid


    Full Text Available Reactions between hydrocarbons and ozone or hydroxyl radicals lead to the formation of oxidized species, including reactive oxygen species (ROS, and secondary organic aerosol (SOA in the troposphere. ROS can be carried deep into the lungs by small aerodynamic particles where they can cause oxidative stress and cell damage. While environmental studies have focused on ROS in the gas-phase and rainwater, it is also important to determine concentrations of ROS on respirable particles. Samples of PM2.5 collected over 3 h at midday on 40 days during November 2011 and September 2012 show that the particulate ROS concentration in Austin, Texas ranged from a minimum value of 0.02 nmol H2O2 (m3 air−1 in December to 3.81 nmol H2O2 (m3 air−1 in September. Results from correlation tests and linear regression analysis on particulate ROS concentrations and environmental conditions (which included ozone and PM2.5 concentrations, temperature, relative humidity, precipitation and solar radiation indicate that ambient particulate ROS is significantly influenced by the ambient ozone concentration, temperature and incident solar radiation. Particulate ROS concentrations measured in this study were in the range reported by other studies in the US, Taiwan and Singapore. This study is one of the first to assess seasonal variations in particulate ROS concentrations and helps explain the influence of environmental conditions on particulate ROS concentrations.

  13. Influence of suspended kelp culture on seabed sediment composition in Heini Bay, China

    Liu, Yanxia; Huang, Haijun; Yan, Liwen; Liu, Xiao; Zhang, Zehua


    Kelp aquaculture activities occupy large nearshore areas with significant effects on sediment properties, primarily caused by the influence of the suspended kelp on local hydrodynamics. Changes in sediment composition and grain-size distributions were investigated prior to and following the commencement of kelp aquaculture activities in Heini Bay in eastern China. Seabed sediment types and the particulate matter in suspension during the kelp seeding and harvesting periods, and in sediment cores, were analyzed. While suspended sediment in the kelp aquaculture area was up to 20% organic material, sediment organic content on the seabed remained at similar levels as areas lacking aquaculture. The composition of the seabed sediment in the kelp aquaculture area became finer-grained by the capture of fine particles. Within the kelp aquaculture area, the sediments are poorly sorted and positively skewed, whereas at the shoreward and seaward of the aquaculture area the sediments are relatively coarse-grained, well-sorted and nearly symmetrically distributed. Therefore, the kelp aquaculture activities not only increase the fine particulate fraction in the sediments within the aquaculture area, but also result in similar deposits seaward of it, indicating that seabed erosion and accretion is also controlled by the sediment source and the hydrodynamic conditions. The analysis of sediment cores showed that kelp culturing refines the sediment by preferentially capturing particles in the 38-40 μm size class, while having no effect on the <32 μm fractions, as evidenced by the positive skew of the surficial sediments. The captured particle size class became well mixed into the sediment, thereby changing the composition of the sediment in the uppermost layer of the core, indicating the existence of continuous and stable hydrodynamic conditions within the kelp aquaculture area. The same effect was observed in the seabed sediments seaward of the aquaculture area.

  14. Chemical composition of suspended sediments in World Rivers: New insights from a new database.

    Viers, Jérôme; Dupré, Bernard; Gaillardet, Jérôme


    The aim of this paper is to present a new database on the chemical composition of suspended matter in World Rivers, together with the associated elemental fluxes. There is a lack of any recent attempt in the literature to update the pioneering work of Martin and Meybeck [Martin, J.-M., Meybeck, M., 1979. Elemental mass balance of material carried by major world rivers. Mar. Chem. 7, 173-206.] and Martin and Whitfield [Martin, J.-M., Whitfield, M., 1983. The significance of the river input of chemical elements to the ocean. Trace metals in sea water Wong, Boyle, Bruland, Burton, Goldberg (Eds) Plenum Publishing Corporation.] regarding the worldwide average major and trace element chemistry of riverine particulate matter. Apart from compiling a new database on particulate matter, this paper also aims to give a "snap-shot" of elemental fluxes for each continent. This approach should allow us to obtain new insights on weathering conditions in different environments and assess the influence of human activities on natural geochemical cycles. Finally, this study demonstrates the large uncertainties currently associated with estimating the flux of sediments transported by rivers. By comparing the riverine suspended sediment fluxes of some metals (Cd, Zn, Ni, Cu, Cr and Pb) given in this study with estimates of the anthropogenic fluxes of these metals to the atmosphere, soils and waters (natural ecosystems) [Nriagu, J.O., 1988. A silent epidemic of environmental poisoning. Environ. Pollut. 50, 139-161.], we can see that riverine fluxes are similar to anthropogenic fluxes. This casts light on the effect of human activities on the cycles of trace elements at the Earth's surface.

  15. Contribution of Root Respiration to Total Soil Respiration in a Leymus chinensis (Trin.) Tzvel. Grassland of Northeast China


    The loss of carbon through root respiration is an important component of grassland carbon budgets. However,few data are available concerning the contribution of root respiration to total soil respiration in grasslands in China. We investigated seasonal variations of soil respiration rate, root biomass, microbial biomass C and organic C content of the soil in a semi-arid Leymus chinensis (Trin.) Tzvel. grassland of northeast China during the 2002 growing season (from May to September). The linear regression relationship between soil respiration rate and root biomass was used to determine the contribution of root respiration to total soil respiration. Soil respiration rate ranged from 2.5 to 11.9 g C/m2 per d with the maximum in late June and minimum in September.The microbial biomass C and organic C content of the soil ranged from 0.3 to 1.5 g C/m2 and from 29 to 34 g C/kg respectively. Root biomass had two peaks, in early June (1.80 kg/m2) and mid-August (1.73 kg/m2). Root respiration rate peaked in mid-August (6.26 g C/m2 per d), whereas microbial respiration rate peaked in late June (7.43 g C/m2 per d). We estimated that the contribution of root respiration to total soil respiration during the growing season ranged from 38% to 76%.

  16. Do different components of terrestrial sources contribute to the riverine suspended load?

    Voss, B. M.; Peucker-Ehrenbrink, B.; Eglinton, T. I.; Galy, V.


    Establishing the relationship between source (bedrock, soil, floodplain sediments, vegetation) and mobilized materials (bedload and suspended load) within a river drainage network is critical to understanding the fate of particulate matter exported to the coastal ocean. First, linking material carried in river channels to its terrestrial sources aides in predicting the reactivity of organic matter associated with mineral particles and understanding which portions of a watershed contribute substantially to organic carbon fluxes and transformations in these systems. Second, identifying terrestrial reservoirs of future riverine suspended material can enhance our ability to comprehensively characterize the chemical and physical nature of fluvial sediments. We present a study of sedimentological and bulk organic carbon properties of sediments from across the Fraser River watershed in southwestern British Columbia, Canada. Bulk samples and size fractions from surface soils and riverbank sediments, as well as vegetation, are analyzed for metrics including carbon and nitrogen content, 13C and 14C composition, and specific surface area. These are compared with measurements of riverine suspended sediments and size fractions of sediments deposited in the Fraser estuary. The correspondence of suspended sediment properties with different portions of soil, alluvial, and vegetation pools from different sites suggests a complex link between source materials and exported material. Such variability may stem from the heterogeneous nature of soil types, hillslope morphology, and runoff regimes in different portions of the drainage basin; settling/resuspension processes during river transit; and/or modification of particle structure and organic matter between mobilization of terrestrial material and arrival at distant downstream sites. The preferential loss/preservation of different size fractions within mineral source materials highlights the unequal importance of different mineral

  17. Suspended Sediment Variability and Erosion Geochemical Budget of the Ganga Basin

    France-Lanord, C.; Galy, V.; Galy, A.; Singh, S. K.


    Himalayan erosion generates one of the world largest sediment transport system. Assessing modern fluxes is difficult in such large river system as there is a large seasonal variability and because floodplain sequestration and the bedload transport are potentially important but not measurable. Measurements on rivers in Bangladesh provide data on dissolved and particulate fluxes. Galy and France-Lanord [1] used a geochemical budget to approach these additional fluxes and proposed that they should be approximately equal to that of the suspended load flux (about 400 Mt/yr for the Ganga). However, such budget relies on the representativeness of the chemical composition attributed to the different endmembers. Here we present new data on river sediments of the Ganga in Bangladesh and in the Gangetic plain that allow a much more reliable assessment of the suspended sediment composition. Sampling has been performed during monsoon periods of 2001, 02 and 04. Sampling includes depth profiling in order to take into account the mineral sorting during transport. Depth profiles show systematic trends. For instance, Al2O3/SiO2 ratio evolve from 0.25-0.35 at the surface down to 0.15-0.27 at 10 m depth mainly as a response to the progressive decrease of the (micas+clays)/quartz ratio. Grain size distribution also evolves in parallel from an unimodal distribution around 20 μm at the surface to a bimodal distribution with a second mode around 200 μm at depth. Elements like Na, which is controlled by plagioclase, and Ca controlled by carbonates do no not show any systematic evolution with depth. Along the Ganga course, the suspended sediments are more progressively depleted in SiO2 likely as a response to the deposition of quartz rich sediments in the floodplain. The data show that in Bangladesh, the suspended sediments are clearly enriched in Al and Fe relative to the average Himalayan sources. Using a simple geochemical mass balance and assuming steady state erosion of the

  18. Acoustic measuring techniques for suspended sediment

    Gruber, P.; Felix, D.; Storti, G.; Lattuada, M.; Fleckenstein, P.; Deschwanden, F.


    Acoustic signals can be used in various ways for suspended sediment monitoring. One possibility which lends itself particularly well in the context of hydropower plants (HPPs), is to use installations for acoustic discharge measurement (ADM). Such installations already exist at waterways of many HPPs. Similar to certain turbidimeters, the attenuation of the forward scattered signal travelling through the water-sediment mixture is correlated with suspended sediment concentration (SSC). This correlation can be based on reference SSCs, e.g. from gravimetric analyses of bottle samples. Without the need of additional sensors and practically maintenance-free, this method is used successfully in the HPP Fieschertal to warn the HPP operator of high SSC to prevent excessive turbine abrasion. Acoustic methods and systems that allow for estimating both SSC and particle size distribution (PSD) are under development. The simultaneous determination of SSC and PSD is not possible using a single frequency. Therefore, multi-frequency approaches are investigated for generally scattered signals. When backscattered signals are used, a stronger frequency dependency can be exploited. However, the reliable simultaneous determination of particle size (and distribution) and concentration is still a major challenge due to a low signal-to-noise ratio and an ill- posed problem of estimating concentration and size from recorded signals. The optimal setup configuration (angles, frequencies) for such a system is not unique and further investigations are recommended.

  19. Fabrication and Characterization of Suspended Carbon Nanotube Devices in Liquid

    Artyukhin, A; Stadermann, M; Stroeve, P; Bakajin, O; Noy, A


    Suspended carbon nanotube devices are a promising platform for future bio-electronic applications. Suspended carbon nanotube transistors have been previously fabricated in air; however all previous attempts to bring them into liquid failed. We analyze forces acting on the suspended nanotube devices during immersion into liquids and during device operation and show that surface tension forces acting on the suspended nanotubes during transfer into the liquid phase are responsible for the nanotube damage. We have developed a new strategy that circumvents these limitations by coating suspended nanotubes with a rigid inorganic shell in the gas phase. The coating reinforces the nanotubes and allows them to survive transfer through the interface. Subsequent removal of the coating in the solution phase restores pristine suspended nanotubes. We demonstrate that devices fabricated using this technique preserve their original electrical characteristics.

  20. Fogging formulations for fixation of particulate contamination in ductwork and enclosures

    Maresca, Jr., Joseph W.; Kostelnik, Lori M.; Kriskivich, James R.; Demmer, Rick L.; Tripp, Julia L.


    A method and an apparatus using aqueous fixatives for fogging of ventilation ductwork, enclosures, or buildings containing dust, lint, and particulates that may be contaminated by radionuclides and other dangerous or unsafe particulate contaminants, which method and apparatus are capable of (1) obtaining full coverage within the ductwork and (2) penetrating and fixing the lint, dust and large particles present in the ductwork so that no airborne particles are released during or after the application of the fixative. New aqueous fogging solutions outperform conventional glycerin-based solutions. These aqueous solutions will fog using conventional methods of application and contain a surfactant to aid wetting and penetration of the lint and dust, a binder to stabilize loose or respirable particles, and an agent to aid in fogging and enhance adhesiveness. The solutions are safe and easy to use.

  1. Organ specific metabolic activation of five extracts of indoor and outdoor particulate matter.

    van Houdt, J J; Coenen, P W; Alink, G M; Boleij, J S; Koeman, J H


    In this study liver and lung homogenates of untreated and Aroclor 1254-pretreated rats (Wistar) and mice (Swiss) were compared for their P-450 content and their capacity to activate extracts of airborne particulate matter, sampled indoors and outdoors. Results show that in addition to liver, lung homogenates of rat (Wistar) and mouse (Swiss) are also able to activate extracts of airborne particulate matter in a comparative way. Uninduced liver and lung homogenates showed only minor differences in activation capacity in the metabolism of airborne particles. In contrast to liver homogenates, Aroclor 1254 pretreatment of test animals did not give strong induction of metabolic activation capacity of lung homogenates. P-450 content was observed in all liver and lung homogenates of mouse and rat and in human lung homogenates. The results obtained in this study suggest that the respiratory tract may be an important site for in vivo bioactivation of respirable particles.

  2. Estuarine modification of dissolved and particulate trace metals in major rivers of East-Hainan, China

    Fu, Jun; Tang, Xiao-Liang; Zhang, Jing; Balzer, Wolfgang


    Dissolved and particulate cadmium, copper, iron, lead, cobalt and nickel were analyzed in surface waters of the Wanquan River estuary and the Wenchang/Wenjiao River estuary in East-Hainan Island during the dry season (December 2006) and two wet seasons (August 2007 and July/August 2008). A major difference to other Chinese rivers was the very low concentration of suspended particles in these tropical Hainan estuaries. In the dissolved phase, a positive deviation from the theoretical dilution line was observed for Cd during different expeditions. Dissolved Cu and Ni essentially behaved conservatively, while Fe, Pb and partly also Co correlated in their negative deviation from simple mixing. Strong seasonal variability was observed only for dissolved Fe, Pb and Cd: sorption by the much higher loading with suspended particles during the dry season lead to a strong lowering of dissolved Fe and Pb, while the opposite was observed for dissolved Cd. In both estuaries all six metals in particulate form showed almost constant values with a tendency for slight decreases along the salinity profile. The normalization to particulate Al revealed some specific particle properties during the different expeditions. The dynamics of Fe chemistry dominated the distribution of Pb in all forms. The distribution coefficients KD showed a general decrease in the order Fe>Pb>Co>Ni>Cu≈Cd. There was no "particle concentration effect"; rather the KD's of Fe and Pb exhibited slightly positive correlations with the suspended particle loadings. Elevated concentrations levels in the Wenchang/Wenjiao river estuary, especially during the wet season 2008, were ascribed to diffuse inputs from aquaculture ponds which girdle the upper estuary. In comparison to major Chinese rivers, the tropical Hainan estuaries (S>0) showed similar levels for Cd, Cu, Pb, Co and Ni in particles and solution, while Fe was enriched in both matrices. On a global scale, neither in the Wanquan river estuary nor in the

  3. Insights on nitrate respiration by Shewanella

    Fengping eWang


    Full Text Available Shewanellae are well known for their ability to utilize a number of electron acceptors and are therefore considered to have important roles in element cycling in the environment, such as nitrogen cycling through dissimilatory nitrate reduction to ammonia (DNRA and denitrification. Possessing two periplasmic nitrate reductase systems (NAP-α and NAP-β is a special trait of the Shewanella genus, and both enzymes are likely to provide selective advantage to the host. This review relates the current knowledge and aspects of the nitrate respiration system of Shewanella. Specifically, the potential physiological functions and regulation mechanisms of the duo-NAP system are discussed in addition to the evolution of anaerobic respiration systems of Shewanella.

  4. A MEMS turbine prototype for respiration harvesting

    Goreke, U.; Habibiabad, S.; Azgin, K.; Beyaz, M. I.


    The design, manufacturing, and performance characterization of a MEMS-scale turbine prototype is reported. The turbine is designed for integration into a respiration harvester that can convert normal human breathing into electrical power through electromagnetic induction. The device measures 10 mm in radius, and employs 12 blades located around the turbine periphery along with ball bearings around the center. Finite element simulations showed that an average torque of 3.07 μNm is induced at 12 lpm airflow rate, which lies in normal breathing levels. The turbine and a test package were manufactured using CNC milling on PMMA. Tests were performed at respiration flow rates between 5-25 lpm. The highest rotational speed was measured to be 9.84 krpm at 25 lpm, resulting in 8.96 mbar pressure drop across the device and 370 mW actuation power.

  5. Cardiac, Skeletal, and smooth muscle mitochondrial respiration

    Park, Song-Young; Gifford, Jayson R; Andtbacka, Robert H I


    Unlike cardiac and skeletal muscle, little is known about vascular smooth muscle mitochondrial function. Therefore, this study examined mitochondrial respiratory rates in the smooth muscle of healthy human feed arteries and compared with that of healthy cardiac and skeletal muscle. Cardiac......, skeletal, and smooth muscle was harvested from a total of 22 subjects (53±6 yrs) and mitochondrial respiration assessed in permeabilized fibers. Complex I+II, state 3 respiration, an index of oxidative phosphorylation capacity, fell progressively from cardiac, skeletal, to smooth muscle (54±1; 39±4; 15......±1 pmol•s(-1)•mg (-1), psmooth muscle (222±13; 115±2; 48±2 umol•g(-1)•min(-1), p

  6. Frost Induces Respiration and Accelerates Carbon Depletion in Trees.

    Or Sperling

    Full Text Available Cellular respiration depletes stored carbohydrates during extended periods of limited photosynthesis, e.g. winter dormancy or drought. As respiration rate is largely a function of temperature, the thermal conditions during such periods may affect non-structural carbohydrate (NSC availability and, ultimately, recovery. Here, we surveyed stem responses to temperature changes in 15 woody species. For two species with divergent respirational response to frost, P. integerrima and P. trichocarpa, we also examined corresponding changes in NSC levels. Finally, we simulated respiration-induced NSC depletion using historical temperature data for the western US. We report a novel finding that tree stems significantly increase respiration in response to near freezing temperatures. We observed this excess respiration in 13 of 15 species, deviating 10% to 170% over values predicted by the Arrhenius equation. Excess respiration persisted at temperatures above 0 °C during warming and reoccurred over multiple frost-warming cycles. A large adjustment of NSCs accompanied excess respiration in P. integerrima, whereas P. trichocarpa neither excessively respired nor adjusted NSCs. Over the course of the years included in our model, frost-induced respiration accelerated stem NSC consumption by 8.4 mg (glucose eq. cm(-3 yr(-1 on average in the western US, a level of depletion that may continue to significantly affect spring NSC availability. This novel finding revises the current paradigm of low temperature respiration kinetics.

  7. Frost Induces Respiration and Accelerates Carbon Depletion in Trees.

    Sperling, Or; Earles, J Mason; Secchi, Francesca; Godfrey, Jessie; Zwieniecki, Maciej A


    Cellular respiration depletes stored carbohydrates during extended periods of limited photosynthesis, e.g. winter dormancy or drought. As respiration rate is largely a function of temperature, the thermal conditions during such periods may affect non-structural carbohydrate (NSC) availability and, ultimately, recovery. Here, we surveyed stem responses to temperature changes in 15 woody species. For two species with divergent respirational response to frost, P. integerrima and P. trichocarpa, we also examined corresponding changes in NSC levels. Finally, we simulated respiration-induced NSC depletion using historical temperature data for the western US. We report a novel finding that tree stems significantly increase respiration in response to near freezing temperatures. We observed this excess respiration in 13 of 15 species, deviating 10% to 170% over values predicted by the Arrhenius equation. Excess respiration persisted at temperatures above 0 °C during warming and reoccurred over multiple frost-warming cycles. A large adjustment of NSCs accompanied excess respiration in P. integerrima, whereas P. trichocarpa neither excessively respired nor adjusted NSCs. Over the course of the years included in our model, frost-induced respiration accelerated stem NSC consumption by 8.4 mg (glucose eq.) cm(-3) yr(-1) on average in the western US, a level of depletion that may continue to significantly affect spring NSC availability. This novel finding revises the current paradigm of low temperature respiration kinetics.

  8. Impact of human activities on soil respiration:A review


    Soil respiration is one of the primary fluxes of carbon between soils and the atmosphere.It is produced by rhizosphere respiration and soil microbial respiration.Soil respiration is not only affected by environmental factors,but also changes with the hu-man-induced disturbances of ecosystems.Land-use,the measures of land management,the pollution of soil,and so on can affect soil respiration and change the soil efflux.According to some research,the authors summed up their impacts on soil respiration by human activities through land-use changes and land-management measures among agroecosystem,grassland ecosystem,and for-est ecosystem.The results showed that (1) when adding fertilization to farmland,the soil respiration will increase;(2) fenced land can decrease soil respiration,while soil respiration in the grazed land at a grassland ecosystem will decline with the increasing of grazing intensity;(3) with grassland fertilization;farmland cultivation;fire,fertilization,and cutting of forest,conflicting results were found in the changes of soil respiration.Perhaps plant species,site condition,and measurement season can lead to different results on soil respiration.

  9. A novel approach to quantifying algal contributions to suspended organic matter from elemental composition

    Aufdenkampe, A. K.; Mayorga, E.; Richardson, D. C.; Newbold, J. D.; Bukaveckas, P. A.; Angradi, T. R.


    Quantitatively distinguishing allochthonous and autochthonous sources of organic matter (OM) transported by stream and river ecosystems has long been a challenge. Stable carbon isotope ratios of algal carbon are temporally and spatially variable in freshwaters and thus poorly constrain OM sources. Here we present a new quantitative approach to estimating algal contributions to suspended particulate OM, based on elemental signatures (%OC, %N) of three particle-type end-members (plant detritus, algae, and mineral-complexed OM). We then applied the mixing model analysis with Monte-Carlo error estimation to quantify the contributions of these three particle types to suspended OM at ~450 river sites in the US Great Rivers (Upper Mississippi, Missouri and Ohio Rivers), at over 100 sites in the Amazon River system and from ~600 samples from one site in the 3rd-order White Clay Creek in the SE Pennsylvania piedmont. We compare model results with measurements of stable isotopes, chlorophyll, nutrients and other variables at this extreme diversity sites with contrasting climate, land use and hydrological conditions. We find that algae typically contribute negligibly to OM in the Amazon but can be very important sources at many sites in the US Great Rivers, but site-specific exceptions to these overall trends can be very informative. In WCC, algal contributions vary seasonally. We then try to explain these differences as a function of differing basin-scale and landuse conditions.

  10. Suspended sediment concentration and particle size distribution, and their relationship with heavy metal content

    S H R Sadeghi; M Kiani Harchegani; H A Younesi


    This paper aims at assessing the feasibility of suspended sediment concentration (SSC) estimation by using predictor variables of heavy metal concentration (HMC, viz., iron, chromium, zinc and nickel) transported in solution and solid. The study was conducted in the Research and Educational Forest Watershed of the Tarbiat Modares University (Kojour) which comprises an area of ca. 50000 ha. For this study, suspended sediment samples were collected from the left bank of the Kojour River twice a week, as well as during runoff events from November 2007 to June 2008. The samples were then prepared through direct digestion and finally analyzed by atomic absorption spectrophotometry (AAS). The relationship between SSC and particle size distribution (PSD) were correlated with HMC by using bivariate and multivariate regression models. Proposed models were then selected based on statistical criteria. The results showed high correlation between dissolved and particulate chromium content with efficiency coefficients beyond 77% ( > 0.001). However, a lower relationship was found between SSC and nickel content. From these results, it is clearly shown that the HMC can practically be estimated by SSC in watersheds with different accuracy and vice versa. It is also understood that heavy metal pollution can be easily managed by controlling SSC.

  11. Chromium in water, suspended particles, sediments and biota in the Iraja River estuary

    Pfeiffer, W.C.; Fiszman, M.; de Lacerda, L.D.; van Weerfelt, M.; Carbonell, N.


    Analyses of chromium concentrations in waters, suspended particles, bottom sediments, fish (Poecilia reticulata), plants (Paspalum vaginatum, Sesuvium portulacastrum, Philoxeros vermicularis), soils and barnacles (Balanus sp.) were performed from August 1976 to September 1980 in samples collected from the Iraja River and inside its estuary in Guanabara Bay (Rio de Janeiro, Brazil). Sediments and water from the Iraja River showed chromium concentrations of 17536 and 23.39 ppm--a thousand times higher than the published data for freshwater systems. Chromium removed from solution by bottom sediments reaches Guanabara Bay linked to particulate matter. Fish and emergent grass inside the river concentrate chromium from water and/or sediment, returning the metal to the system as detritus. Soil and plants inside the estuary concentrate chromium thirty and ten times higher than in the control area. The vegetal community exhibits a concentration factor smaller than that related to soil and prevents the return of chromium to the estuarine waters. Inside the Guanabara Bay, Balanus sp. appears to be an effective biological monitor as it concentrates chromium in soft tissues 10/sup 3/ times higher than values found in suspended particles (0.012 ml/sup -1/).

  12. Modelling suspended-sediment propagation and related heavy metal contamination in floodplains: a parameter sensitivity analysis

    Hostache, R.; Hissler, C.; Matgen, P.; Guignard, C.; Bates, P.


    Fine sediments represent an important vector of pollutant diffusion in rivers. When deposited in floodplains and riverbeds, they can be responsible for soil pollution. In this context, this paper proposes a modelling exercise aimed at predicting transport and diffusion of fine sediments and dissolved pollutants. The model is based upon the Telemac hydro-informatic system (dynamical coupling Telemac-2D-Sysiphe). As empirical and semiempirical parameters need to be calibrated for such a modelling exercise, a sensitivity analysis is proposed. An innovative point in this study is the assessment of the usefulness of dissolved trace metal contamination information for model calibration. Moreover, for supporting the modelling exercise, an extensive database was set up during two flood events. It includes water surface elevation records, discharge measurements and geochemistry data such as time series of dissolved/particulate contaminants and suspended-sediment concentrations. The most sensitive parameters were found to be the hydraulic friction coefficients and the sediment particle settling velocity in water. It was also found that model calibration did not benefit from dissolved trace metal contamination information. Using the two monitored hydrological events as calibration and validation, it was found that the model is able to satisfyingly predict suspended sediment and dissolve pollutant transport in the river channel. In addition, a qualitative comparison between simulated sediment deposition in the floodplain and a soil contamination map shows that the preferential zones for deposition identified by the model are realistic.

  13. Continuous respirable mine dust monitor development

    Cantrell, B.K.; Williams, K.L.; Stein, S.W. [and others


    In June 1992, the Mine Safety and Health Administration (MSHA) published the Report of the Coal Mine Respirable Dust Task Group, Review of the Program to Control Respirable Coal Mine Dust in the United States. As one of its recommendations, the report called for the accelerated development of two mine dust monitors: (1) a fixed-site monitor capable of providing continuous information on dust levels to the miner, mine operator, and to MSHA, if necessary, and (2) a personal sampling device capable of providing both a short-term personal exposure measurement as well as a full-shift measurement. In response to this recommendation, the U.S. Bureau of Mines initiated the development of a fixed-site machine-mounted continuous respirable dust monitor. The technology chosen for monitor development is the Rupprecht and Patashnick Co., Inc. tapered element oscillating microbalance. Laboratory and in-mine tests have indicated that, with modification, this sensor can meet the humidity and vibration requirements for underground coal mine use. The U.S. Department of Energy Pittsburgh Research Center (DOE-PRC) is continuing that effort by developing prototypes of a continuous dust monitor based on this technology. These prototypes are being evaluated in underground coal mines as they become available. This effort, conducted as a joint venture with MSHA, is nearing completion with every promise of success.

  14. Quantitative Application Study on Remote Sensing of Suspended Sediment

    CHEN Yi-mei; XU Su-dong; LIN Qiang


    Quantitative application on remote sensing of suspended sediment is an important aspect of the engineering application of remote sensing study.In this paper,the Xiamen Bay is chosen as the study area.Eleven different phases of the remote sensing data are selected to establish a quantitative remote sensing model to map suspended sediment by using remote sensing images and the quasi-synchronous measured sediment data.Based on empirical statistics developed are the conversion models between instantaneous suspended sediment concentration and tidally-averaged suspended sediment concentration as well as the conversion models between surface layer suspended sediment concentration and the depth-averaged suspended sediment concentration.On this basis,the quantitative application integrated model on remote sensing of suspended sediment is developed.By using this model as well as multi-temporal remote sensing images,multi-year averaged suspended sediment concentration of the Xiamen Bay are predicted.The comparison between model prediction and observed data shows that the multi-year averaged suspended sediment concentration of studied sites as well as the concentration difference of neighboring sites can be well predicted by the remote sensing model with an error rate of 21.61% or less,which can satisfy the engineering requirements of channel deposition calculation.

  15. Suspended sediment, carbon and nitrogen transport in a regulated Pyrenean river.

    López-Tarazón, José A; López, Pilar; Lobera, Gemma; Batalla, Ramon J


    Regulation alters the characteristics of rivers by transforming parts of them into lakes, affecting their hydrology and also the physical, chemical, and biological characteristics and dynamics. Reservoirs have proven to be very effective retaining particulate materials, thereby avoiding the downstream transport of suspended sediment and the chemical substances associated with it (e.g. Carbon, C, or Nitrogen, N). The study of fluvial transport of C and N is of great interest since river load represents a major link to the global C and N cycles. Moreover, reservoirs are the most important sinks for organic carbon among inland waters and have a potential significance as nitrogen sinks. In this respect, this paper investigates the effects of a Pyrenean reservoir on the runoff, suspended sediment, C and N derived from the highly active Ésera and Isábena rivers. Key findings indicate that the reservoir causes a considerable impact on the Ésera-Isábena river fluxes, reducing them dramatically as almost all the inputs are retained within the reservoir. Despite the very dry study year (2011-2012), it can be calculated that almost 300,000 t of suspended sediment were deposited into the Barasona Reservoir, from which more than 16,000 were C (i.e. 2200 t as organic C) and 222 t were N. These values may not be seen as remarkable in a wider global context but, assuming that around 30 h m(3) of sediment are currently stored in the reservoir, figures would increase up to ca. 2.6×10(6) t of C (i.e. 360,000 t of organic C) and 35,000 t of N. Nevertheless, these values are indicative and should be treated with caution as there is incomplete understanding of all the processes which affect C and N. Further investigation to establish a more complete picture of C and N yields and budgets by monitoring the different processes involved is essential.

  16. Biomass burning as the main source of organic aerosol particulate matter in Malaysia during haze episodes.

    Radzi bin Abas, M; Oros, Daniel R; Simoneit, B R T


    The haze episodes that occurred in Malaysia in September-October 1991, August-October 1994 and September-October 1997 have been attributed to suspended smoke particulate matter from biomass burning in southern Sumatra and Kalimantan, Indonesia. In the present study, polar organic compounds in aerosol particulate matter from Malaysia are converted to their trimethylsilyl derivatives and analyzed by gas chromatography-mass spectrometry in order to better assess the contribution of the biomass burning component during the haze episodes. On the basis of this analysis, levoglucosan was found to be the most abundant organic compound detected in almost all samples. The monosaccharides, alpha- and beta-mannose, the lignin breakdown products, vanillic and syringic acids and the minor steroids, cholesterol and beta-sitosterol were also present in some samples. The presence of the tracers from smoke overwhelmed the typical signatures of emissions from traffic and other anthropogenic activities in the urban areas.

  17. Biomass burning as the main source of organic aerosol particulate matter in Malaysia during haze episodes

    Abas, M. Radzi bin [Malaya Univ., Dept. of Chemistry, Kuala Lumpur (Malaysia); Oros, Daniel R.; Simoneit, B.R.T. [Oregon State Univ., Environmental and Petroleum Geochemistry Group, Corvallis, OR (United States)


    The haze episodes that occurred in Malaysia in September-October 1991, August-October 1994 and September-October 1997 have been attributed to suspended smoke particulate matter from biomass burning in southern Sumatra and Kalimantan, Indonesia. In the present study, polar organic compounds in aerosol particulate matter from Malaysia are converted to their trimethylsilyl derivatives and analyzed by gas chromatography-mass spectrometry in order to better assess the contribution of the biomass burning component during the haze episodes. On the basis of this analysis, levoglucosan was found to be the most abundant organic compound detected in almost all samples. The monosaccharides, {alpha}- and {beta}-mannose, the lignin breakdown products, vanillic and syringic acids and the minor steroids, cholesterol and {beta}-sitosterol were also present in some samples. The presence of the tracers from smoke overwhelmed the typical signatures of emissions from traffic and other anthropogenic activities in the urban areas. (Author)

  18. Upwelled spectral radiance distribution in relation to particulate matter in sea water

    Clark, D. K.; Strong, A. E.; Baker, E. T.


    Spectral analysis of water color and concurrent measurements of the relative concentration of various particulate and dissolved constituents within a broad range of water types are necessary to quantify ocean color observations and successfully relate them to various biological and physical processes that can be monitored by remote sensing. Some of the results of a Nimbus-G prelaunch cruise in connection with the Coastal Zone Color Scanner (CZCS) experiment, which was carried out in the Gulf of Mexico in October 1977, are presented and discussed. Based upon a small but diverse sample of near-surface measurements, it appears possible to estimate total suspended particulate matter (SPM) to useful accuracies by forming ratios of the spectral radiances measured at wavelengths falling near the centers of certain CZCS bands, viz., 440 nm:550 nm and 440 nm:520 nm. Furthermore, the analysis suggests a very high degree of covariation between SPM and phytoplankton pigments except for certain well-defined special cases.

  19. Particulate emissions from residential wood combustion: Final report: Norteast regional Biomass Program


    The objective of this study was to provide a resource document for the Northeastern states when pursuing the analysis of localized problems resulting from residential wood combustion. Specific tasks performed include assigning emission rates for total suspended particulates (TSP) and benzo(a)pyrene (BaP) from wood burning stoves, estimating the impact on ambient air quality from residential wood combustion and elucidating the policy options available to Northeastern states in their effort to limit any detrimental effects resulting from residential wood combustion. Ancillary tasks included providing a comprehensive review on the relevant health effects, indoor air pollution and toxic air pollutant studies. 77 refs., 11 figs., 25 tabs.

  20. Polarization signatures of airborne particulates

    Raman, Prashant; Fuller, Kirk A.; Gregory, Don A.


    Exploratory research has been conducted with the aim of completely determining the polarization signatures of selected particulates as a function of wavelength. This may lead to a better understanding of the interaction between electromagnetic radiation and such materials, perhaps leading to the point detection of bio-aerosols present in the atmosphere. To this end, a polarimeter capable of measuring the complete Mueller matrix of highly scattering samples in transmission and reflection (with good spectral resolution from 300 to 1100 nm) has been developed. The polarization properties of Bacillus subtilis (surrogate for anthrax spore) are compared to ambient particulate matter species such as pollen, dust, and soot. Differentiating features in the polarization signatures of these samples have been identified, thus demonstrating the potential applicability of this technique for the detection of bio-aerosol in the ambient atmosphere.

  1. Treatment of suspended solids and heavy metals from urban stormwater runoff by a tree box filter.

    Geronimo, F K F; Maniquiz-Redillas, M C; Tobio, J A S; Kim, L H


    Particulates, inorganic and toxic constituents are the most common pollutants associated with urban stormwater runoff. Heavy metals such as chromium, nickel, copper, zinc, cadmium and lead are found to be in high concentration on paved roads or parking lots due to vehicle emissions. In order to control the rapid increase of pollutant loads in stormwater runoff, the Korean Ministry of Environment proposed the utilization of low impact developments. One of these was the application of tree box filters that act as a bioretention treatment system which executes filtration and sorption processes. In this study, a tree box filter located adjacent to an impervious parking lot was developed to treat suspended solids and heavy metal concentrations from urban stormwater runoff. In total, 11 storm events were monitored from July 2010 to August 2012. The results showed that the tree box filter was highly effective in removing particulates (up to 95%) and heavy metals (at least 70%) from the urban stormwater runoff. Furthermore, the tree box filter was capable of reducing the volume runoff by 40% at a hydraulic loading rate of 1 m/day and below.

  2. Total suspended dust and heavy metal levels emitted from a workplace compared with nearby residential houses

    Abdul-Wahab, Sabah A.; Yaghi, Basma

    Total suspended particulate matter (TSP) were collected from the workplace in Sohar Industrial Estate (SIE) in Oman. The samples were taken from 19 different industrial activities that represent major sources of particulate matter in the SIE. The collected samples were analyzed for 9 heavy metals (Cr, Cu, Mn, Ni, Pb, Zn, Cd, V and Mo) by using the inductively coupled plasma optical emission spectrometry analysis (ICP-OES). Furthermore, the indoor TSP and heavy metal concentrations were measured inside 12 houses within Sohar residential area to determine the contributions of various industrial activities on nearby residential houses. The results indicated that the mean concentrations of heavy metals in the TSP were too low to yield any known environmental health effects. In general, the results showed that the concentrations of heavy metals in the workplaces of SIE and its nearby houses were low compared to the guideline values. In addition, the values were low in comparison with other known sites around the world. Moreover, significant contribution from industrial sources at SIE was evidenced at nearby houses.

  3. Cycles of selected trace elements in the South Atlantic: Vertical transport and interactions between particulates and solution; Zum Kreislauf ausgewaehlter Spurenmetalle im Suedatlantik: Vertikaltransport und Wechselwirkung zwischen Partikeln und Loesung

    Dierssen, H.


    Subjects: Concentrations, vertical and regional distributions of dissolved and suspended particulate trace elements; Trace element fluxes - vertical, regional, seasonal; The role of particulate organic carbon and atmospheric dust in vertical transport; Fractionation of trace elements in particulate material during transport. [German] Themen dieser Arbeit sind: Konzentrationen, vertikale und regionale Verteilungen von geloesten und suspendierten partikulaeren Spurenelementem (SE); SE-Fluesse vertikal, regional und saisonal; die Rolle des partikulaeren organischen Kohlenstoffs und des atmosphaerischen Staubeintrags beim Vertikaltransport; Fraktionierung von SE im partikulaeren Material beim Transport. (orig./SR)

  4. Material Instabilities in Particulate Systems

    Goddard, J. D.


    Following is a brief summary of a theoretical investigation of material (or constitutive) instability associated with shear induced particle migration in dense particulate suspensions or granular media. It is shown that one can obtain a fairly general linear-stability analysis, including the effects of shear-induced anisotropy in the base flow as well as Reynolds dilatancy. A criterion is presented here for simple shearing instability in the absence of inertia and dilatancy.

  5. Suspended sediment yield in Texas watersheds

    Coonrod, Julia Ellen Allred

    The Texas Water Development Board collected suspended sediment samples across the state of Texas for approximately 60 years. Until this research, no comprehensive analysis of the data had been conducted. This study compiles the suspended sediment data along with corresponding streamflow and rainfall. GIS programs are developed which characterize watersheds corresponding to the sediment gauging stations. The watersheds are characterized according to topography, climate, soils, and land use. All of the data is combined to form several SAS data sets which can subsequently be analyzed using regression. Annual data for all of the stations across the state are classified temporally and spatially to determine trends in the sediment yield. In general, the suspended sediment load increases with increasing runoff but no correlation exists with rainfall. However, the annual average rainfall can be used to classify the watersheds according to climate, which improves the correlation between sediment load and runoff. The watersheds with no dams have higher sediment loads than watersheds with dams. Dams in the drier parts of Texas reduce the sediment load more than dams in the wetter part of the state. Sediment rating curves are developed separately for each basin in Texas. All but one of the curves fall into a band which varies by about two orders of magnitude. The study analyzes daily time series data for the Lavaca River near Edna station. USGS data are used to improve the sediment rating curve by the addition of physically related variables and interaction terms. The model can explain an additional 41% of the variability in sediment concentration compared to a simple bivariate regression of sediment load and flow. The TWDB daily data for the Lavaca River near Edna station are used to quantify temporal trends. There is a high correlation between sediment load and flowrate for the Lavaca River. The correlation can be improved by considering a flow-squared term and by

  6. Effects of elevated CO2 concentrations on soil microbial respiration and root/rhizosphere respiration in-forest soils


    The two main components of soil respiration,i.e.,root/rhizosphere and microbial respiration,respond differently to elevated atmospheric CO2 concentrations both in mechanism and sensitivity because they have different substrates derived from plant and soil organic matter,respectively.To model the carbon cycle and predict the carbon source/sink of forest ecosystems,we must first understand the relative contributions of root/rhizosphere and microbial respiration to total soil respiration under elevated CO2 concentrations.Root/rhizosphere and soil microbial respiration have been shown to increase,decrease and remain unchanged under elevated CO2 concentrations.A significantly positive relationship between root biomass and root/rhizosphere respiration has been found.Fine roots respond more strongly to elevated CO2 concentrations than coarse roots.Evidence suggests that soil microbial respiration is highly variable and uncertain under elevated CO2 concentrations.Microbial biomass and activity are related or unrelated to rates of microbial respiration.Because substrate availability drives microbial metabolism in soils,it is likely that much of the variability in microbial respiration results from differences in the response of root growth to elevated CO2 concentrations and subsequent changes in substrate production.Biotic and abiotic factors affecting soil respiration were found to affect both root/rhizosphere and microbial respiration.

  7. Tracing pyrogenic carbon suspended in rivers on a global scale

    Wiedemeier, Daniel B.; Haghipour, Negar; McIntyre, Cameron P.; Eglinton, Timothy I.; Schmidt, Michael W. I.


    Combustion-derived, pyrogenic carbon (PyC) is a persistent organic carbon fraction. Due to its aromatic and condensed nature (Wiedemeier et al., 2015), it is relatively resistant against chemical and biological degradation in the environment, leading to a comparatively slow turnover, which would support carbon sequestration. PyC is produced on large scales (hundreds of teragrams) in biomass burning events such as wildfires, and by combustion of fossil fuel in industry and traffic. PyC is an inherently terrestrial product and thus has predominantly been investigated in soils and the atmosphere. Much fewer studies are available about the subsequent transport of PyC to rivers and oceans. Recently, awareness has been rising about the mobility of PyC from terrestrial to marine systems and its fate in coastal and abyssal sediments was recognized (Mitra et al, 2013). It is therefore crucial to extend our knowledge about the PyC cycle by tracing PyC through all environmental compartments. By comparing its biogeochemical behavior and budgets to that of other forms of organic carbon, it will eventually be possible to elucidate PyC's total spatiotemporal contribution to carbon sequestration. In this study, we use a state-of-the-art PyC molecular marker method (Wiedemeier et al., 2013, Gierga et al., 2014) to trace quantity, quality as well as 13C and 14C signature of PyC in selected major river systems around the globe (Godavari, Yellow, Danube, Fraser, Mackenzie and Yukon river). Different size fractions of particulate suspended sediment are analyzed and compared across a north-south gradient. Previous studies suggested a distinct relationship between the 14C age of plant-derived suspended carbon and the latitude of the river system, indicating slower cycling of plant biomarkers in higher latitudes. We discuss this pattern with respect to PyC, its isotopic signature and quality and the resulting implications for the global carbon and PyC cycle. References Wiedemeier, D.B. et

  8. Particulate matter in exhaled breath condensate: A promising indicator of environmental conditions

    Pinheiro, Teresa, E-mail: [ITN, E.N. 10, 2685-953 Sacavem (Portugal); CFN-UL, Prof. Gama Pinto, 2, 1649-003 Lisboa (Portugal); Alexandra Barreiros, M. [LNEG, Estrada Paco do Lumiar, 22, 1649-038 Lisboa (Portugal); Alves, Luis C. [ITN, E.N. 10, 2685-953 Sacavem (Portugal); CFN-UL, Prof. Gama Pinto, 2, 1649-003 Lisboa (Portugal); Felix, Pedro M.; Franco, Cristiana; Sousa, Joana; Almeida, S.M. [ITN, E.N. 10, 2685-953 Sacavem (Portugal)


    Assessing the retention of aerosol particles in the human lung, one of the most important pathways of absorption, is a demanding issue. At present, there is no direct biomarker of exposure for the respiratory system. The collection of exhaled breath condensate (EBC) constitutes a new non-invasive method for sampling from the lung. However, the heterogeneity of the sample due to particulate matter suspended in the condensed phase may influence the quality of analytical results in occupational assessments. The main objective of the study was to confirm the presence of particulate matter in the condensate, to investigate how large the particles in suspension could be and to determine their elemental contents relative to those of EBC matrix. This paper reports on preliminary nuclear microprobe data of particulate matter in EBC. The sizes and the elemental contents of particles suspended in EBC of workers of a lead processing industry and in EBC of non-exposed individuals were inspected. Results demonstrated that EBC of workers contain large aerosol particles, isolated and in agglomerates, contrasting with non-exposed individuals. The particles contained high concentrations of Cl, Ca, Zn and Pb that are elements associated to the production process. These elements were also present in the EBC matrix although in much lower levels, suggesting that a fraction of the inhaled particulate matter was solubilised or their size-ranges were below the nuclear microprobe resolution. Therefore, the morphological characterization of individual particles achieved with nuclear microprobe techniques helped describing EBC constituents in detail, to comprehend their origin and enabled to delineate methodological procedures that can be recommended in occupational assessments. These aspects are critical to the validation of EBC as a biomarker of exposure to metals for the respiratory system.

  9. [Effect of Water and Sediment Regulation on the Transport of Particulate Organic Carbon in the Lower Yellow River].

    Zhang, Ting-ting; Yao, Peng; Wang, Jin-peng; Pan, Hui-hui; Gao, Li-meng; Zhao, Bin; Li, Dong


    Both natural processes and human activities in river basins have important impacts on the transport of riverine organic carbon (OC). Better understanding of the riverine OC transport processes is critical for the studies of global carbon cycling. Suspended particulate matters collected from the Lijin Station in the lower Yellow River during the water and sediment regulation ( WSR) period in 2012 (19 June-20 July) were analyzed for grain size, particulate OC (POC) and stable carbon isotopic ratios (delta13C) to investigate-the sources, composition, abundance of POC and the effect of WSR on the transport of POC. The results showed that the WSR in 2012 could be divided into two stages according to the variation of water and sediment discharges: the water-release stage (WRS) and the sediment-release stage (SRS). Variations of the water discharge, sediments, POC and delta13C in these two stages reflected the impacts of WSR on the sources of particulate matters and associated OC. The water discharge in the WRS stage was the highest (4270 m3 x s(-1)), and the sediments scoured from the riverbed in the lower reaches were the major source of suspended particulate matters in this stage, therefore the particles were characterized by relatively coarse grain size (13.9 microm in average of median grain size), low POC (avg. 0.38%) and relatively enriched and constant delta13C (-24.2% per hundred +/- 0.3% per hundred), probably because POC in the sediments scoured from the riverbed had old radiocarbon ages and high degradation. The suspended particulate matters in the SRS stage were mainly derived from the upstream reservoirs and flushed riverbanks due to local rainstorm, and the POC age was relatively young, thus this stage was characterized by high concentration of suspended particulate matters (up to 17.8 kg x m(-3)), fine particles (5.9 microm in average of median grain size), high POC (avg. 0.50%), and depleted and varied delta13C values (-24.8% per hundred +/- 0.6% per

  10. Indoor air pollution by particulate matter; Ryushijo busshitsu ni yoru osen

    Irie, T. [Shinshu Univ., Nagano (Japan). Faculty of Education


    This paper explains the standards and the purport of the law for maintenance of sanitation in buildings, the outbreak of sickness relating to the sick-building syndrome and its countermeasures, etc., in connection with particulate matters in the indoor environment. The law of 1970 specified 0.15mg/m{sup 3} as the standard of indoor maintenance control for suspended particulate matters. As a number of data were subsequently accumulated, however, it was revealed that tobacco smoke particles were the very cause of the indoor particulate pollution though it was unpredicted at the beginning. As a result, it led to the development of high level filters, improvement of air conditioning operation, measures for smoking, and so on, for which the regulation of 0.15mg/m{sup 3} has been believed to be correct after all. The most frequently disqualified item was particulate matters at the initial enforcement of the law, but the moisture standard has been ranked first in recent years. The problems of tobacco smoke, asbestos and allergens are particularly to be watched among many problems involved. 10 refs., 2 figs., 3 tabs.

  11. Particulate n-alkanes and fatty acids in the ChangJiang river system

    WU Ying; ZHANG Jing; LIU Sumei; ZHANG Zaifeng; CHEN Hongtao; XIONG Hui


    Particulate samples were collected from the Changjiang river system during a flood period, in May 1997, and POC, stable isotope and lipids associated with particles were examined. Results showed the decrease (0.84% ~ 1.88%) of organic carbon content from the upper reaches to the estuary.δ13C values of particulate organic carbon was in the range of -24.9×10-3 to -26.6×10-3, which were close to the isotopic signature of continental C3 vegetation. Total particulate n-alkanes concentrations varied from 1.4 to 10.1μg/dm3,or from 23.7 to 107μg/g of total suspended matter. Fatty acids were present in all the samples, from 1.4 to 5.4μg/dm3, with saturated and unsaturated straight-chain and branched compounds in the carbon number range from C12 to C30. Both δ13C and the ratio of carbon content to nitrogen content indicate the predominance of terrestrial inputs (soil organic matter) among the particles. The biomarker approach has been used to identify the relative portion of terrigenous and autochthonous fraction in the particulate samples. The distribution of fatty acids suggests a striking phytoplanktonic and microbial signal in most particle samples. The terrestrial alkanes are used to estimate the contribution of terrestrial inputs along the mainstream.

  12. Anodic aluminum oxide with fine pore size control for selective and effective particulate matter filtering

    Zhang, Su; Wang, Yang; Tan, Yingling; Zhu, Jianfeng; Liu, Kai; Zhu, Jia


    Air pollution is widely considered as one of the most pressing environmental health issues. Particularly, atmospheric particulate matters (PM), a complex mixture of solid or liquid matter suspended in the atmosphere, are a harmful form of air pollution due to its ability to penetrate deep into the lungs and blood streams, causing permanent damages such as DNA mutations and premature death. Therefore, porous materials which can effectively filter out particulate matters are highly desirable. Here, for the first time, we demonstrate that anodic aluminum oxide with fine pore size control fabricated through a scalable process can serve as effective and selective filtering materials for different types of particulate matters (such as PM2.5, PM10). Combining selective and dramatic filtering effect, fine pore size control and a scalable process, this type of anodic aluminum oxide templates can potentially serve as a novel selective filter for different kinds of particulate matters, and a promising and complementary solution to tackle this serious environmental issue.

  13. Leaching of Particulate and Dissolved Organic Carbon from Compost Applied to Bioretention Systems

    Iqbal, Hamid; Flury, Markus; Mullane, Jessica; Baig, Muhammad


    Compost is used in bioretention systems to improve soil quality, to promote plant growth, and to remove metal contaminants from stormwater. However, compost itself, particularly when applied freshly, can be a source of contamination of the stormwater. To test the potential contamination caused by compost when applied to bioretention systems, we continuously leached a compost column with water under unsaturated conditions and characterized dissolved and particulate organic matter in the leachate. Freshly applied, mature compost leached up to 400 mg/L of dissolved organic carbon and 2,000 mg/L of suspended particulate organic carbon. It required a cumulative water flux of 4,000 mm until concentrations of dissolved and particulate organic carbon declined to levels typical for surface waters. Although, dissolved and particulate organic carbon are not contaminants per se, they can facilitate the movement of metals, thereby enhancing the mobility of toxic metals present in stormwater. Therefore, we recommended that compost is washed before it is applied to bioretention systems. Keywords compost; leachate; alkali extract; dissolved organic carbon; flux

  14. Characterization of airborne particulates in Bangkok urban area by neutron activation analysis.

    Nouchpramool, S; Sumitra, T; Leenanuphunt, V


    Samples of airborne particulates were collected in a residential area and in an area near a busy highway in Bangkok during the period from January 1997 to May 1998. A stacked filter system was used for the former site and a Partisol 2000 was used for the latter site. Both 2.5 microns and 10-micron particulates were collected every week. The total suspended particulate matters were also collected at the latter site. The samples were analyzed by neutron activation analysis utilizing neutron flux from a 2-MW TRIGA MARK III research reactor. The elements most frequently detected in the airborne particulates were Al, As, Br, Ca, Ce, Cl, Co, Cr, Cs, Fe, I, K, La, Mg, Mn, Na, Rb, Sb, Sc, Sm, Th, Ti, V, and Zn. The enrichment factor and factor analysis were used to investigate trends, sources, and origin of the atmospheric aerosols. Anthropogenic elements in road dust, construction dust, motor vehicles emission, and other combustion components were identified. A comparative study of data between both sites was performed and it was found that the mass concentration in the area close to the highway was about three times higher than in the residential area.

  15. Lung cancer, cardiopulmonary mortality, and long-term exposure to fine particulate air pollution

    Pope III, C.A.; Burnett, R.T.; Thun, M.J.; Calle, E.E.; Krewski, D.; Ito, K.; Thurston, G.D. [Brigham Young University, Provo, UT (United States)


    A study was conducted to the relationship between long-term exposure to fine particulate air pollution and all-cause, lung cancer, and cardiopulmonary mortality. Vital status and cause of death data were collected by the American Cancer Society as part of the Cancer Prevention II study, an ongoing prospective mortality study, which enrolled approximately 1.2 million adults in 1982. Participants completed a questionnaire detailing individual risk factor data (age, sex, race, weight, height, smoking history, education, marital status, diet, alcohol consumption, and occupational exposures). The risk factor data for approximately 500 000 adults were linked with air pollution data for metropolitan areas throughout the United States and combined with vital status and cause of death data through December 31, 1998. Fine particulate and sulfur oxide-related pollution were found to be associated with all-cause, lung cancer, and cardiopulmonary mortality. Each 10-{mu}g/m{sup 3} elevation in fine particulate air pollution was associated with approximately a 4%, 6%, and 8% increased risk of all-cause, cardiopulmonary, and lung cancer mortality, respectively. Measures of coarse particle fraction and total suspended particles were not consistently associated with mortality. It was concluded that long-term exposure to combustion-related fine particulate air pollution is an important environmental risk factor for cardiopulmonary and lung cancer mortality. 31 refs., 5 figs., 2 tabs.

  16. Determination of lead in fine particulates by slurry sampling electrothermal atomic absorption spectrometry.

    Yu, J C; Ho, K F; Lee, S C


    A simple method for determining lead in fine particulates (PM2.5) by using electrothermal atomic absorption spectrometry (ETAAS) has been developed. Particulates collected on Nuclepore filter by using a dichotomous sampler were suspended in diluted nitric acid after ultrasonic agitation. The dislodging efficiency is nearly 100% after agitation for 5 min. In order to study the suspension behavior of PM2.5 in solvents, a Brookhaven ZetaPlus Particle Size Analyzer was used to determine the particle size distribution and suspension behavior of air particulates in the solvent. The pre-digestion and modification effect of nitric acid would be discussed. Palladium was added as a chemical modifier and the temperature program of ETAAS was changed in order to improve the recovery. The slurry was introduced directly into a graphite tube for atomization. The metal content in the sample was determined by the standard addition method. In addition, a conventional acid digestion procedure was applied to verify the efficiency of the slurry sampling method. It offers a quick and efficient alternative method for heavy metal characterization in fine particulates.

  17. Organics and Suspended Solids Removal from Hospital

    Fakhri Y. Hmood


    Full Text Available The Sequencing Batch Reactor (SBR method is used for treating samples of waste water taken from hospitals in Mosul. Many run periods are used (6-24 hours for             6 months. It is found that the organics and suspended solids removal increase with increasing the period of run, it is in the range ( 96-82 % and ( 100-95 % respectively, while the pH values are nearly neutral (7.05 to 7.5.     BOD5 and SS concentrations of the effluent are within the limits of Iraqi standards,  40:30 mg/l respectively. Hence, SBR method could be used for treating hospitals, small factories and some  residential sectors waste waters.  

  18. Design consideration for magnetically suspended flywheel systems

    Anand, D.; Kirk, J. A.; Frommer, D. A.


    Consideration is given to the design, fabrication, and testing of a magnetically suspended flywheel system for energy storage applications in space. The device is the prototype of a system combining passive suspension of the flywheel plate by samarium cobalt magnets and active control in the radial direction using eight separate magnetic coils. The bearing assembly was machined from a nickel-iron alloy, and the machine parts are all hydrogen annealed. Slots in the magnetic plate allow four independent quadrants for control. The motor/generator component of the system is a brushless dc-permanent magnetic/ironless engine using electronic communication. The system has been tested at over 2500 rpm with satisfactory results. The system characteristics of the flywheel for application in low earth orbit (LEO) are given in a table.

  19. Flywheel energy storage. II - Magnetically suspended superflywheel

    Kirk, J. A.; Studer, P. A.


    This article, the second of a two part paper, describes the general design requirements for a flywheel energy storage system. A new superflywheel energy storage system, using a spokeless, magnetically suspended, composite material pierced disk rotor is proposed. The new system is configured around a permanent magnet ('flux biased') magnetic suspension system with active control in the radial direction and passive control in the axial direction. The storage ring is used as a moving rotor and electronic commutation of stationary armature coils is proposed. There is no mechanical contact with the rotating ring and long life and low run down losses are projected. A discussion of major components for a 10 kwh system is presented.

  20. Actively suspended counter-rotating machine

    Studer, Philip A. (Inventor)


    A counter-rotating machine, such as a positive displacement pump having a pair of meshed, non-contacting helical screws (10,12), subjects its rotating members to axial and radial thrust forces when used for such purposes as compression of liquid or gaseous phase fluids while transporting them through a pump cavity (11,13). Each helical screw (10,12) has a shaft (17,17') which is actively suspended at opposite ends (11a,11b) of the pump cavity by a servo-controlled magnetic bearing assembly (19) and a servo-controlled rotary drive motor (20). Both bearing assemblies and drive motors are mounted on the outside of the pump cavity (11,13). Opto-electric angular position sensors (250) provide synchronization between radial orientation of the drive motors. The bearing assemblies and drive motors conjugately provide axial stabilization and radial centering of the helical screws during volumetric compression of aspirated liquid or gaseous phase fluids.

  1. Shapes of a Suspended Curly Hair

    Miller, J. T.; Lazarus, A.; Audoly, B.; Reis, P. M.


    We investigate how natural curvature affects the configuration of a thin elastic rod suspended under its own weight, as when a single strand of hair hangs under gravity. We combine precision desktop experiments, numerics, and theoretical analysis to explore the equilibrium shapes set by the coupled effects of elasticity, natural curvature, nonlinear geometry, and gravity. A phase diagram is constructed in terms of the control parameters of the system, namely the dimensionless curvature and weight, where we identify three distinct regions: planar curls, localized helices, and global helices. We analyze the stability of planar configurations, and describe the localization of helical patterns for long rods, near their free end. The observed shapes and their associated phase boundaries are then rationalized based on the underlying physical ingredients.

  2. Traffic signatures in suspended dust at pedestrian levels in semiarid zones: Implications for human exposure

    Meza-Figueroa, Diana; González-Grijalva, Belem; Del Río-Salas, Rafael; Coimbra, Rute; Ochoa-Landin, Lucas; Moreno-Rodríguez, Verónica


    Deeper knowledge on dust suspension processes along semiarid zones is critical for understanding potential impacts on human health. Hermosillo city, located in the heart of the Sonoran Desert was chosen to evaluate such impacts. A one-year survey of Total Suspended Particulate Matter (TSPM) was conducted at two different heights (pedestrian and rooftop level). The minimum values of TSPM were reported during monsoon season and winter. Maximum values showed a bimodal distribution, with major peaks associated with increase and decrease of temperature, as well as decreasing humidity. Concentrations of TSPM were significantly exceeded at pedestrian level (∼44% of analyzed days) when compared to roof level (∼18% of analyzed days). Metal concentrations of As, Pb, Cu, Sb, Be, Mg, Ni, and Co were higher at pedestrian level than at roof level. Pixel counting and interpretations based on scanning electron microscopy of dust filters showed a higher percentage of fine particulate fractions at pedestrian level. These fractions occur mainly as metal-enriched agglomerates resembling coarser particles. According to worldwide guidelines, particulate matter sampling should be conducted by monitoring particle sizes equal and inferior to PM10. However, this work suggests that such procedures may compromise risk assessment in semiarid environments, where coarse particles act as main carriers for emergent contaminants related to traffic. This effect is especially concerning at pedestrian level, leading to an underestimation of potential impacts of human exposure. This study brings forward novel aspects that are of relevance for those concerned with dust suspension processes across semiarid regions and related impact on human health.

  3. Mesozooplankton production, grazing and respiration in the Bay of Bengal: Implications for net heterotrophy

    Fernandes, Veronica; Ramaiah, N.


    Mesozooplankton samples were collected from the mixed layer along a central (along 88°E) and a western transect in the Bay of Bengal during four seasons covered between 2001 and 2006 in order to investigate spatio-temporal variability in their biomass. At these stations, grazing and respiration rates were measured from live zooplankton hauled in from the surface during December 2005. Akin to the mesozooplankton "paradox" in the central and eastern Arabian Sea, biomass in the mixed layer was more or less invariant in the central and western Bay of Bengal, even as the chl a showed marginal temporal variation. By empirical equation, the mesozooplankton production rate calculated to be 70-246 mg C m- 2 d- 1 is on par with the Arabian Sea. Contrary to the conventional belief, mesozooplankton grazing impact was up to 83% on primary production (PP). Low PP coupled with very high zooplankton production (70% of PP) along with abundant bacterial production (50% of the PP; Ramaiah et al., 2009) is likely to render the Bay of Bengal net heterotrophic, especially during the spring intermonsoon. Greater estimates of fecal pellet-carbon egestion by mesozooplankton compared to the average particulate organic carbon flux in sediment traps, implies that much of the matter is recycled by heterotrophic communities in the mixed layer facilitating nutrient regeneration for phytoplankton growth. We also calculated that over a third of the primary production is channelized for basin-wide zooplankton respiration that accounts for ~ 52 Mt C annually. In the current scenario of global warming, if low (primary) productive warm pools like the Bay of Bengal continue to be net heterotrophic, negative implications like enhanced emission of CO2 to the atmosphere, increased particulate flux to the deeper waters and greater utilization of dissolved oxygen resulting in expansion of the existing oxygen minimum zone are imminent.

  4. Adjustment of Forest Ecosystem Root Respiration as Temperature Warms

    Andrew J. Burton; Jerry M. Melillo; Serita D. Frey


    Adjustment of ecosystem root respiration to warmer climatic conditions can alter the autotrophic portion of soil respiration and influence the amount of carbon available for biomass production. We examined 44 published values of annual forest root respiration and found an increase in ecosystem root respiration with increasing mean annual temperature (MAT),but the rate of this cross-ecosystem increase (Q10 = 1.6) is less than published values for short-term responses of root respiration to temperature within ecosystems (Q10 = 2-3). When specific root respiration rates and root biomass values were examined, there was a clear trend for decreasing root metabolic capacity (respiration rate at a standard temperature) with increasing MAT. There also were tradeoffs between root metabolic capacity and root system biomass, such that there were no instances of high growing season respiration rates and high root biomass occurring together. We also examined specific root respiration rates at three soil warming experiments at Harvard Forest, USA, and found decreases in metabolic capacity for roots from the heated plots. This decline could be due to either physiological acclimation or to the effects of co-occurring drier soils on the measurement date. Regardless of the cause, these findings clearly suggest that modeling efforts that allow root respiration to increase exponentially with temperature, with Qt0 values of 2 or more, may over-predict root contributions to ecosystem CO2 efflux for future climates and underestimate the amount of C available for other uses,including net primary productivity.

  5. Aged riverine particulate organic carbon in four UK catchments

    Adams, Jessica L., E-mail: [Centre for Ecology and Hydrology, Lancaster Environment Centre, Lancaster, LA1 4AP (United Kingdom); Tipping, Edward, E-mail: [Centre for Ecology and Hydrology, Lancaster Environment Centre, Lancaster, LA1 4AP (United Kingdom); Bryant, Charlotte L., E-mail: [NERC Radiocarbon Facility, East Kilbride G75 0QF, Scotland (United Kingdom); Helliwell, Rachel C., E-mail: [The James Hutton Institute, Craigiebuckler, Aberdeen AB15 8QH Scotland (United Kingdom); Toberman, Hannah, E-mail: [Centre for Ecology and Hydrology, Lancaster Environment Centre, Lancaster, LA1 4AP (United Kingdom); School of Environmental Sciences, University of Liverpool, Liverpool L69 3GP (United Kingdom); Quinton, John, E-mail: [Lancaster Environment Centre, Lancaster University, Lancaster LA1 4YQ (United Kingdom)


    The riverine transport of particulate organic matter (POM) is a significant flux in the carbon cycle, and affects macronutrients and contaminants. We used radiocarbon to characterise POM at 9 riverine sites of four UK catchments (Avon, Conwy, Dee, Ribble) over a one-year period. High-discharge samples were collected on three or four occasions at each site. Suspended particulate matter (SPM) was obtained by centrifugation, and the samples were analysed for carbon isotopes. Concentrations of SPM and SPM organic carbon (OC) contents were also determined, and were found to have a significant negative correlation. For the 7 rivers draining predominantly rural catchments, PO{sup 14}C values, expressed as percent modern carbon absolute (pMC), varied little among samplings at each site, and there was no significant difference in the average values among the sites. The overall average PO{sup 14}C value for the 7 sites of 91.2 pMC corresponded to an average age of 680 {sup 14}C years, but this value arises from the mixing of differently-aged components, and therefore significant amounts of organic matter older than the average value are present in the samples. Although topsoil erosion is probably the major source of the riverine POM, the average PO{sup 14}C value is appreciably lower than topsoil values (which are typically 100 pMC). This is most likely explained by inputs of older subsoil OC from bank erosion, or the preferential loss of high-{sup 14}C topsoil organic matter by mineralisation during riverine transport. The significantly lower average PO{sup 14}C of samples from the River Calder (76.6 pMC), can be ascribed to components containing little or no radiocarbon, derived either from industrial sources or historical coal mining, and this effect is also seen in the River Ribble, downstream of its confluence with the Calder. At the global scale, the results significantly expand available information for PO{sup 14}C in rivers draining catchments with low erosion rates

  6. Influence of seasonal variability of lower Mississippi River discharge, temperature, suspended sediments, and salinity on oil-mineral aggregate formation.

    Danchuk, Samantha; Willson, Clinton S


    Under certain conditions, oil droplets that have separated from the main oil slick may become coated by suspended sediments forming oil-mineral aggregates (OMAs). The formation of these aggregates depends on suspended particulate characteristics, temperature, salinity, mixing energy, droplet size and number, and oil properties. The OMAs do not re-coalesce with the slick and tend not to adhere to surfaces, potentially evading surface cleanup measures, enhancing opportunity for biodegradation and reducing shoreline oiling. Potential OMA formation was quantified during four distinct states of the Lower Mississippi River during a typical year using empirical relationships from laboratory and field studies for three common oils and different combinations of discharge, temperature, suspended sediments, and salinity. The largest potential OMA formation for the two lighter oils, up to 36% of the total release volume, was in the winter and spring, when high sediment availability promotes formation. For the denser, high-viscosity oil, the peak potential OMA formation, 9% of the release volume, occurred in the summer, when the salinity was higher. These results provide some evidence that, depending on environmental and spill characteristics, the formation of OMAs could be an important, but unaccounted for, process in the fate and transport of oils released in the Lower Mississippi River and should be included in oil spill dispersion models and post-spill site assessment and remediation actions.

  7. Removal of suspended solids from municipal wastewater using geotextile columns

    Akram, M.H. [Texas Tech Univ., Lubbock, Texas (United States); Kotha, K.K. [Hillis-Carnes Inc., Manassas, VA (United States)


    A laboratory investigation was conducted to investigate the filtration behavior of geotextiles to remove suspended solids from municipal wastewater. Four nonwoven geotextiles were used in this preliminary investigation. The study also involved evaluating the suspended solids removal efficiency and regeneration potential of geotextiles for using as filter media. Wastewater samples were collected from the local wastewater treatment plant. Influent and effluent suspended solids concentration, chemical oxygen demand, and effluent flow rates were monitored during the tests. During filtration tests, suspended solids were retained on the upstream face and within the geotextile as wastewater passed through it. Due to the formation of a thin layer of suspended solids or filter cake on the upstream face of the geotextile, the effluent flow rate and suspended solids concentration decreased exponentially with time. When the effluent flow rate reduced below 90%, the filter media was backwashed to restore its filtering efficiency, for reuse. Based on the results of this study, it was concluded that using geotextile columns, it was possible to remove 50 to 70% of suspended solids and decrease in chemical oxygen demand from 70 to 90% from the influent. This technique may be suitable for treating wastewater streams with low inflow and suspended solids concentrations, preferably in the range of 100 to 200 mg/L. The technique may be further evaluated for determining its suitability for treatment of wastewater generated from less populated areas and as a polishing step after secondary treatment. (author)

  8. Energy values of suspended detritus in Andaman Sea

    Krishnakumari, L.; Royan, J.P.; Sumitra-Vijayaraghavan

    Energy content of suspended detritus was determined in Andaman Sea waters during April-May 1988. The caloric content of suspended detritus ranged from 987 to 7040 cal. per gram dry wt with an average value of 5530 cal. per gram dry wt. The results...

  9. Simulation of suspended sediment transport initialized with satellite derived suspended sediment concentrations

    Ratheesh Ramakrishnan; A S Rajawat


    Suspended sediment transport in the Gulf of Kachchh is simulated utilizing the suspended sediment concentration (SSC) derived from Oceansat OCM imagery, as the initial condition in MIKE-21 Mud Transport model. Optimization of the model mud parameters, like settling velocity and critical shear stress for erosion are realized with respect to the sediment size distribution and the bottom bed materials observed in the Gulf. Simulated SSCs are compared with alternate OCM derived SSC. The results are observed to be impetus where the model is able to generate the spatial dynamics of the sediment concentrations. Sediment dynamics like deposition, erosion and dispersion are explained with the simulated tidal currents and OCM derived sediment concentrations. Tidal range is observed as the important physical factor controlling the deposition and resuspension of sediments within the Gulf. From the simulation studies; maximum residual current velocities, tidal fronts and high turbulent zones are found to characterise the islands and shoals within the Gulf, which results in high sediment concentrations in those regions. Remarkable variability in the bathymetry of the Gulf, different bed materials and varying tidal conditions induces several circulation patterns and turbulence creating the unique suspended sediment concentration pattern in the Gulf.

  10. Pulmonary inflammation and crystalline silica in respirable coal mine dust: dose-response

    E D Kuempel; M D Attfield; V Vallyathan; N L Lapp; J M Hale; R J Smith; V Castranova


    This study describes the quantitative relationships between early pulmonary responses and the estimated lungburden or cumulative exposure of respirable-quartz or coal mine dust. Data from a previous bronchoalveolar lavage (BAL) study in coal miners ( = 20) and nonminers ( = 16) were used including cell counts of alveolar macrophages (AMs) and polymorphonuclear leukocytes (PMNs), and the antioxidant superoxide dismutase (SOD) levels. Miners’ individual working lifetime particulate exposures were estimated from work histories and mine air sampling data, and quartz lung-burdens were estimated using a lung dosimetry model. Results show that quartz, as either cumulative exposure or estimated lung-burden, was a highly statistically significant predictor of PMN response ( < 0.0001); however cumulative coal dust exposure did not significantly add to the prediction of PMNs ( = 0.2) above that predicted by cumulative quartz exposure ( < 0.0001). Despite the small study size, radiographic category was also significantly related to increasing levels of both PMNs and quartz lung burden (-values < 0.04). SOD in BAL fluid rose linearly with quartz lung burden ( < 0.01), but AM count in BAL fluid did not ( > 0.4). This study demonstrates dose-response relationships between respirable crystalline silica in coal mine dust and pulmonary inflammation, antioxidant production, and radiographic small opacities.

  11. What does respirator certification tell us about filtration of ultrafine particles?

    Eninger, Robert M; Honda, Takeshi; Reponen, Tiina; McKay, Roy; Grinshpun, Sergey A


    Recent interest in exposures to ultrafine particles (less than 100 nm) in both environmental and occupational settings led the authors to question whether the protocols used to certify respirator filters provide adequate attention to ultrafine aerosols. The authors reviewed the particle size distribution of challenge aerosols and evaluated the aerosol measurement method currently employed in the National Institute for Occupational Safety and Health (NIOSH) particulate respirator certification protocol for its ability to measure the contribution of ultrafine particles to filter penetration. Also considered were the differences between mechanical and electrically charged (electret) filters in light of the most penetrating particle size. It was found that the sodium chloride (NaCl) and dioctylphthalate (DOP) aerosols currently used in respirator certification tests contain a significant fraction of particles in the ultrafine region. However, the photometric method deployed in the certification test is not capable of adequately measuring light scatter of particles below approximately 100 nm in diameter. Specifically, 68% (by count) and 8% (by mass) of the challenge NaCl aerosol particles and 10% (by count) and 0.3% (by mass) of the DOP particles below 100 nm do not significantly contribute to the filter penetration measurement. In addition, the most penetrating particle size for electret filters likely occurs at 100 nm or less under test conditions similar to those used in filter certification. The authors conclude, therefore, that the existing NIOSH certification protocol may not represent a worst-case assessment for electret filters because it has limited ability to determine the contribution of ultrafine aerosols, which include the most penetrating particle size for electret filters. Possible strategies to assess ultrafine particle penetration in the certification protocol are discussed.

  12. Diesel particulate filter with zoned resistive heater

    Gonze, Eugene V [Pinckney, MI


    A diesel particulate filter assembly comprises a diesel particulate filter (DPF) and a heater assembly. The DPF filters a particulate from exhaust produced by an engine. The heater assembly has a first metallic layer that is applied to the DPF, a resistive layer that is applied to the first metallic layer, and a second metallic layer that is applied to the resistive layer. The second metallic layer is etched to form a plurality of zones.

  13. Zone heated diesel particulate filter electrical connection

    Gonze, Eugene V.; Paratore, Jr., Michael J.


    An electrical connection system for a particulate filter is provided. The system includes: a particulate filter (PF) disposed within an outer shell wherein the PF is segmented into a plurality of heating zones; an outer mat disposed between the particulate filter and the outer shell; an electrical connector coupled to the outer shell of the PF; and a plurality of printed circuit connections that extend along the outer surface of the PF from the electrical connector to the plurality of heating zones.

  14. Particulate organic carbon and particulate humic material in the Arabian Sea

    Sardessai, S.; Sarma, V.V.S.S.; DileepKumar, M.

    Variations in particulate organic carbon (POC) and particulate humic material (PHM) were studied in winter (February-March 1995) and intermonsoon (April-May 1994) seasons in the Arabian Sea. Higher levels of POC were found in the north than...

  15. Can soil respiration estimate neglect the contribution of abiotic exchange?

    Xi CHEN; WenFeng WANG; GePing LUO; Hui YE


    This study examines the hypothesis that soil respiration can always be interpreted purely in terms of biotic processes, neglecting the contribution of abiotic exchange to CO2 fluxes in alkaline soils of arid areas that characterize 5%of the Earth’s total land surface. Analyses on flux data collected from previous studies suggested reconciling soil respiration as organic (root/microbial respiration) and inorganic (abiotic CO2 exchange) respiration, whose contributions in the total CO2 flux were determined by soil alkaline content. On the basis of utilizing mete-orological and soil data collected from the Xinjiang and Central Asia Scientific Data Sharing Platform, an incorpo-rated model indicated that inorganic respiration represents almost half of the total CO2 flux. Neglecting the abiotic module may result in overestimates of soil respiration in arid alkaline lands, which partly explains the long-sought“missing carbon sink”.

  16. Tillage Effects on Soil Properties & Respiration

    Rusu, Teodor; Bogdan, Ileana; Moraru, Paula; Pop, Adrian; Duda, Bogdan; Cacovean, Horea; Coste, Camelia


    Soil tillage systems can be able to influence soil compaction, water dynamics, soil temperature and soil structural condition. These processes can be expressed as changes of soil microbiological activity, soil respiration and sustainability of agriculture. Objectives of this study were: 1) to assess the effects of tillage systems (Conventional System-CS, Minimum Tillage-MT, No-Tillage-NT) on soil compaction, soil temperature, soil moisture and soil respiration and 2) to establish the relationship that exists in changing soil properties. Three treatments were installed: CS-plough + disc; MT-paraplow + rotary grape; NT-direct sowing. The study was conducted on an Argic-Stagnic Faeoziom. The MT and NT applications reduce or completely eliminate the soil mobilization, due to this, soil is compacted in the first year of application. The degree of compaction is directly related to soil type and its state of degradation. The state of soil compaction diminished over time, tending toward a specific type of soil density. Soil moisture was higher in NT and MT at the time of sowing and in the early stages of vegetation and differences diminished over time. Moisture determinations showed statistically significant differences. The MT and NT applications reduced the thermal amplitude in the first 15 cm of soil depth and increased the soil temperature by 0.5-2.20C. The determinations confirm the effect of soil tillage system on soil respiration; the daily average was lower at NT (315-1914 mmoli m-2s-1) and followed by MT (318-2395 mmoli m-2s-1) and is higher in the CS (321-2480 mmol m-2s-1). Comparing with CS, all the two conservation tillage measures decreased soil respiration, with the best effects of no-tillage. An exceeding amount of CO2 produced in the soil and released into the atmosphere, resulting from aerobic processes of mineralization of organic matter (excessive loosening) is considered to be not only a way of increasing the CO2 in the atmosphere, but also a loss of

  17. Filter casing for respirators. Filtergehaeuse fuer Atemschutzmasken

    Pantaleon-Stemberg, G.


    A filter casing for respirators, in which filter inserts are held exchangeably by means of a holder engaging into the wall of the casing, is improved in that filter inserts of different height and in various combinations can be fixed in it with the same holder. For that purpose the holder is designed as a socket which is open at both ends and can be fixed to the inside wall of the filter casing and is axially displaceable and envelops the filter insert, the end circumference of said socket having a fixing device projecting inwards.

  18. Bicarbonate alters cellular responses in respiration assays.

    Krycer, James R; Fisher-Wellman, Kelsey H; Fazakerley, Daniel J; Muoio, Deborah M; James, David E


    Metabolic assay buffers often omit bicarbonate, which is susceptible to alkalinisation in an open environment. Here, we assessed the effect of including bicarbonate in respirometry experiments. By supplementing HEPES-buffered media with low concentrations of bicarbonate, we found increased respiration in adipocytes and hepatocytes, but not myotubes. This was observed across multiple respirometry platforms and was independent of effects on enhanced insulin sensitivity, pH drift, or mitochondrial function. Permeabilised cell experiments suggest that bicarbonate increases substrate availability, likely by acting as a cofactor for carboxylase enzymes. This emphasises the importance of buffer choice in experimental biology. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. Electrically heated particulate filter embedded heater design

    Gonze, Eugene V.; Chapman, Mark R.


    An exhaust system that processes exhaust generated by an engine is provided. The system generally includes a particulate filter (PF) that filters particulates from the exhaust wherein an upstream end of the PF receives exhaust from the engine and wherein an upstream surface of the particulate filter includes machined grooves. A grid of electrically resistive material is inserted into the machined grooves of the exterior upstream surface of the PF and selectively heats exhaust passing through the grid to initiate combustion of particulates within the PF.

  20. Evaluation of Five Decontamination Methods for Filtering Facepiece Respirators

    Viscusi, Dennis J.; Bergman, Michael S.; Eimer, Benjamin C.; Ronald E. Shaffer


    Concerns have been raised regarding the availability of National Institute for Occupational Safety and Health (NIOSH)-certified N95 filtering facepiece respirators (FFRs) during an influenza pandemic. One possible strategy to mitigate a respirator shortage is to reuse FFRs following a biological decontamination process to render infectious material on the FFR inactive. However, little data exist on the effects of decontamination methods on respirator integrity and performance. This study eval...

  1. 21 CFR 1404.715 - What notice does the suspending official give me if I am suspended?


    ... 21 Food and Drugs 9 2010-04-01 2010-04-01 false What notice does the suspending official give me if I am suspended? 1404.715 Section 1404.715 Food and Drugs OFFICE OF NATIONAL DRUG CONTROL POLICY... this part, and any other Office of National Drug Control Policy procedures governing...

  2. Particulate organic matter in rivers of Fukushima: An unexpected carrier phase for radiocesiums.

    Naulier, Maud; Eyrolle-Boyer, Frédérique; Boyer, Patrick; Métivier, Jean-Michel; Onda, Yuichi


    The role of particulate organic matter in radiocesium transfers from soils to rivers was investigated in areas contaminated by the Fukushima Daiichi Nuclear Power Plant accident. Suspended and deposited sediments, filtered water, macro organic debris and dead leaves were sampled along the six most contaminated coastal river catchments of the Fukushima prefecture in the early autumns 2013 and 2014. Radiocesium concentrations of river samples and total organic carbon concentrations in suspended and deposited sediments were measured. Radiocesium concentrations of suspended and deposited sediments were significantly correlated to (137)Cs inventories in soils and total organic carbon. The distributions of radiocesium between the organic and mineral phases of both types of sediment were assessed by using a modelling approach. The results suggest that, during the early autumn season, the organic fraction was the main phase that carried the radiocesiums in deposited sediments and in suspended sediments for suspended loads organic matter. Since it is well known that organic compounds generally do not significantly adsorb radiocesium onto specific sites, several hypotheses are suggested: 1) Radiocesiums may have been absorbed into organic components at the early stage of atmospheric radioactive deposits and/or later due to biomass recycling and 2) Those elements would be partly carried by glassy hot particles together with organic matter transported by rivers in Fukushima. Both hypotheses would lead to conserve the amount of radiocesiums associated with particles during their transfers from the contaminated areas to the marine environment. Finally, such organically bound radiocesium would lead to significant deliveries of bioavailable radiocesium for living organisms at Fukushima.

  3. Suspended matter and fluid mud off Alleppey, southwest coast of India

    Shynu, R.; Rao, V. Purnachandra; Samiksha, S. V.; Vethamony, P.; Naqvi, S. W. A.; Kessarkar, Pratima M.; Babu, M. T.; Dineshkumar, P. K.


    Time series measurements on suspended particulate matter (SPM) were made at one non-mud bank (M1) and two mud bank stations (M2 and M3) off Alleppey, south west coast of India. The mean SPM was low in surface (6.2 mg/l) and mid-depth (3.7 mg/l) waters and higher in bottom-depth waters (24.6 mg/l) of these stations, during both pre-monsoon and monsoon seasons. Near bed suspended sediment results indicated low SPM during July (0.042 g/l) and September (0.018 g/l) at M1, but very high SPM at M2 (9.2 g/l) and M3 (6.2 g/l) during July that decreased (M2: 0.033 g/l; M3: 0.1 g/l) again in September. Observations based on LISST-25X indicated that optical transmission (OT) was high (80-100%) in surface and mid-depth waters but decreased with increasing depth. Near bed waters at M2 and M3 stations showed ∼1 m thick fluid layer with 0% OT and with high particle volume concentrations (150-200 μl/l) during monsoon. Bottom sediments were clayey silts. Sediments of <63 μm fraction were skewed towards finer size at M1 but to coarser size at M2 and M3 stations during monsoon. The water content of the sediment decreased and wet bulk density increased at M2 and M3 stations, while it was the opposite at M1 station during the monsoon. Our results indicated the presence of fluid mud close to the bottom at M2 and M3 stations. As the wave height decreased from ∼3 m in May to 0.76 m in July, the dissipated wave energy probably liquefied, eroded and re-suspended the bottom sediment to form fluid mud. Upwelling currents may have been involved in the up keep and transportation of fluid mud. The suspended mud resettled at the bottom soon after the monsoon event.

  4. A survey of respirators usage for airborne chemicals in Korea.

    Han, Don-Hee; Kang, Min-Sun


    A questionnaire survey was undertaken to identify the current status of respirator usage in manufacturing work environments subject to gas/vapor chemicals exposure in Korea and to suggest improvements to enhance the effectiveness of respirator usage. The number of target companies included 17 big companies, 110 small & mid-size companies, and 5 foreign companies, and the number of respondents included 601 workers and 69 persons in charge of respirators (PCR). The results explained clearly that respirator programs in practice were extremely poor in small & mid-sized companies. The findings indicated that the selection of respirators was not appropriate. Quarter mask including filtering facepiece was the most common facepiece form for respirator and was worn by sixty-four percent. Not a little proportion of respondents (33%) complained about the fit: faceseal leakage between the face and facepiece. A filtering facepiece with carbon fiber filter was used as a substitution for a gas/vapor respirator. Another result was that the PCR respondents' perception of the administration of respirators was very low. The results of this survey suggest that regal enforcement of respiratory protection programs should be established in Korea. On the basis of these findings, respiratory protection programs should include respirator selection, maintenance, training, and fit testing.

  5. [The development of a respiration and temperature monitor].

    Du, X; Wu, B; Liu, Y; He, Q; Xiao, J


    This paper introduces the design of a monitoring system to measure the respiration and temperature of a body with an 8Xc196 single-chip microcomputer. This system can measure and display the respiration wave, respiration frequency and the body temperature in real-time with a liquid crystal display (LCD) and give an alarm when the parameters are beyond the normal scope. In addition, this device can provide a 24 hours trend graph of the respiration frequency and the body temperature parameters measured. Data can also be exchanged through serial communication interfaces (RS232) between the PC and the monitor.

  6. Autotrophic and heterotrophic components of soil respiration in permafrost zone.

    Udovenko, Maria; Goncharova, Olga


    Soil carbon dioxide emissions production is an important integral indicator of soil biological activity and it includes several components: the root respiration and microbial decomposition of organic matter. Separate determination of the components of soil respiration is necessary for studying the balance of carbon in the soil and to assessment its potential as a sink or source of carbon dioxide. The aim of this study was testing field methods of separate determination of root and microbial respiration in soils of north of West Siberia. The research took place near the town Nadym, Yamalo-Nenets Autonomous District (north of West Siberia).The study area was located in the northern taiga with sporadic permafrost. Investigations were carried out at two sites: in forest and in frozen peatland. 3 methods were tested for the separation of microbial and root respiration. 1) "Shading"; 2) "Clipping"(removing the above-ground green plant parts); 3)a modified method of roots exclusion (It is to compare the emission of soils of "peat spots", devoid of vegetation and roots, and soils located in close proximity to the spots on which there is herbaceous vegetation and moss). For the experiments on methods of "Shading" and "Clipping" in the forest and on the frozen peatland ware established 12 plots, 1 x 1 m (3 plots in the forest and at 9 plots on frozen peatland; 4 of them - control).The criterions for choosing location sites were the similarity of meso- and microrelief, the same depth of permafrost, the same vegetation. Measurement of carbon dioxide emissions (chamber method) was carried out once a day, in the evening, for a week. Separation the root and microbial respiration by "Shading" showed that in the forest the root respiration contribution is 5%, and microbial - 95%. On peatlands root respiration is 41%, 59% of the microbial. In the experiment "Clipping" in peatlands root respiration is 56%, the microbial respiration - 44%, in forest- root respiration is 17%, and

  7. respiration and transpiration characteristics of selected fresh fruits ...


    Key words : packaging, respiration, transpiration, temperature, relative humidity. RESUME ... microbial attack. Shelf life is inversely ... of relative humidity. MATERIALS AND METHODS ..... physiology and crop preservation. (M.) Lieberman ed.


    M.A. Ebadian, Ph.D.; S.K. Dua, Ph.D., C.H.P.; Hillol Guha, Ph.D.


    During deactivation and decommissioning activities, thermal cutting tools, such as plasma torch, laser, and gasoline torch, are used to cut metals. These activities generate fumes, smoke and particulates. These airborne species of matter, called aerosols, may be inhaled if suitable respiratory protection is not used. Inhalation of the airborne metallic aerosols has been reported to cause ill health effects, such as acute respiratory syndrome and chromosome damage in lymphocytes. In the nuclear industry, metals may be contaminated with radioactive materials. Cutting these metals, as in size reduction of gloveboxes and tanks, produces high concentrations of airborne transuranic particles. Particles of the respirable size range (size < 10 {micro}m) deposit in various compartments of the respiratory tract, the fraction and the site in the respiratory tract depending on the size of the particles. The dose delivered to the respiratory tract depends on the size distribution of the airborne particulates (aerosols) and their concentration and radioactivity/toxicity. The concentration of airborne particulate matter in an environment is dependent upon the rate of their production and the ventilation rate. Thus, measuring aerosol size distribution and generation rate is important for (1) the assessment of inhalation exposures of workers, (2) the selection of respiratory protection equipment, and (3) the design of appropriate filtration systems. Size distribution of the aerosols generated during cutting of different metals by plasma torch was measured. Cutting rates of different metals, rate of generation of respirable mass, as well as the fraction of the released kerf that become respirable were determined. This report presents results of these studies. Measurements of the particles generated during cutting of metal plates with a plasma arc torch revealed the presence of particles with mass median aerodynamic diameters of particles close to 0.2 {micro}m, arising from

  9. Bacterial respiration of arsenic and selenium

    Stolz, J.F.; Oremland, R.S.


    Oxyanions of arsenic and selenium can be used in microbial anaerobic respiration as terminal electron acceptors. The detection of arsenate and selenate respiring bacteria in numerous pristine and contaminated environments and their rapid appearance in enrichment culture suggest that they are widespread and metabolically active in nature. Although the bacterial species that have been isolated and characterized are still few in number, they are scattered throughout the bacterial domain and include Gram- positive bacteria, beta, gamma and epsilon Proteobacteria and the sole member of a deeply branching lineage of the bacteria, Chrysiogenes arsenatus. The oxidation of a number of organic substrates (i.e. acetate, lactate, pyruvate, glycerol, ethanol) or hydrogen can be coupled to the reduction of arsenate and selenate, but the actual donor used varies from species to species. Both periplasmic and membrane-associated arsenate and selenate reductases have been characterized. Although the number of subunits and molecular masses differs, they all contain molybdenum. The extent of the environmental impact on the transformation and mobilization of arsenic and selenium by microbial dissimilatory processes is only now being fully appreciated.

  10. Central cholinergic regulation of respiration: nicotinic receptors

    Xuesi M SHAO; Jack L FELDMAN


    Nicotinic acetylcholine receptors (nAChRs) are expressed in brainstem and spinal cord regions involved in the control of breathing. These receptors mediate central cholinergic regulation of respiration and effects of the exogenous ligand nicotine on respiratory pattern. Activation of a4* nAChRs in the preBotzinger Complex (preBotC), an essential site for normal respiratory rhythm generation in mammals, modulates excitatory glutamatergic neurotransmission and depolarizes preBotC inspiratory neurons, leading to increases in respiratory frequency. nAChRs are also present in motor nuclei innervating respiratory muscles. Activation of post- and/or extra-synaptic a4* nAChRs on hypoglossal (XII) motoneurons depolarizes these neurons, potentiating tonic and respiratory-related rhythmic activity. As perinatal nicotine exposure may contribute to the pathogenesis of sudden infant death syndrome (SIDS), we discuss the effects of perinatal nicotine exposure on development of the cholinergic and other neurotransmitter systems involved in control of breathing. Advances in understanding of the mechanisms underlying central cholinergic/nicotinic modulation of respiration provide a pharmacological basis for exploiting nAChRs as therapeutic targets for neurological disorders related to neural control of breathing such as sleep apnea and SIDS.

  11. Underwater breathing: the mechanics of plastron respiration

    Flynn, M. R.; Bush, John W. M.

    The rough, hairy surfaces of many insects and spiders serve to render them water-repellent; consequently, when submerged, many are able to survive by virtue of a thin air layer trapped along their exteriors. The diffusion of dissolved oxygen from the ambient water may allow this layer to function as a respiratory bubble or , and so enable certain species to remain underwater indefinitely. Maintenance of the plastron requires that the curvature pressure balance the pressure difference between the plastron and ambient. Moreover, viable plastrons must be of sufficient area to accommodate the interfacial exchange of O2 and CO2 necessary to meet metabolic demands. By coupling the bubble mechanics, surface and gas-phase chemistry, we enumerate criteria for plastron viability and thereby deduce the range of environmental conditions and dive depths over which plastron breathers can survive. The influence of an external flow on plastron breathing is also examined. Dynamic pressure may become significant for respiration in fast-flowing, shallow and well-aerated streams. Moreover, flow effects are generally significant because they sharpen chemical gradients and so enhance mass transfer across the plastron interface. Modelling this process provides a rationale for the ventilation movements documented in the biology literature, whereby arthropods enhance plastron respiration by flapping their limbs or antennae. Biomimetic implications of our results are discussed.

  12. Quantized conductance of a suspended graphene nanoconstriction

    Tombros, Nikolaos; Junesch, Juliane; Guimarães, Marcos H D; Marun, Ivan J Vera; Jonkman, Harry T; van Wees, Bart J


    A yet unexplored area in graphene electronics is the field of quantum ballistic transport through graphene nanostructures. Recent developments in the preparation of high mobility graphene are expected to lead to the experimental verification and/or discovery of many new quantum mechanical effects in this field. Examples are effects due to specific graphene edges, such as spin polarization at zigzag edges of a graphene nanoribbon and the use of the valley degree of freedom in the field of graphene valleytronics8. As a first step in this direction we present the observation of quantized conductance at integer multiples of 2e^2/h at zero magnetic field and 4.2 K temperature in a high mobility suspended graphene ballistic nanoconstriction. This quantization evolves into the typical quantum Hall effect for graphene at magnetic fields above 60mT. Voltage bias spectroscopy reveals an energy spacing of 8 meV between the first two subbands. A pronounced feature at 0.6 2e^2/h present at a magnetic field as low as ~0.2T...

  13. The contribution of root respiration of Pinus koraiensis seedlings to total soil respiration under elevated CO2 concentrations

    LIUYing; HANShi-jie; LIXue-feng; ZHOUYu-mei; ZHANGJun-hui; JIAXia


    The impacts of elevated atmospheric CO2 concentrations (500 IJmol.mol-land 700 μmol.mo1-1) on total soil respiration and the contribution of root respiration of Pinus koraiensis seedlings were investigated from May to October in 2003 at the Research Station of Changbai Mountain Forest Ecosystems, Chinese Academy of Sciences, Jilin Province, China. After four growing seasons in top-open chambers exposed to elevated CO2, the total soil respiration and roots respiration of Pinus koraiensis seedlings were measured by a LI-6400-09 soil CO2 flux chamber. Three PVC cylinders in each chamber were inserted about 30 cm into the soil instantaneously to terminate the supply of current photosynthates from the tree canopy to roots for separating the root respiration from total soil respiration. Soil respirations both inside and outside of the cylinders were measured on June 16, August 20 and October 8, respectively. The results indicated that: there was a marked diurnal change in air temperature and soil temperature at depth of 5 cm on June 16, the maximum of soil temperature at depth of 5 cm laggedb ehind that of air temperature, no differences in temperature between treatments were found (P>0.05). The total soil respiration and soil respiration with roots severed showed strong diurnal and seasonal patterns. There was marked difference in total soil respiration and soil respiration with roots severed between treatments (P<0.01); Mean total soil respiration and contribution of root under different treatments were 3.26, 4.78 and 1.47 μmol .m-2.s-1, 11.5%, 43.1% and 27.9% on June 16, August 20 and October 8. respectivelv.

  14. Can we distinguish autotrophic respiration from heterotrophic respiration in a field site using high temporal resolution CO2 flux measurements?

    Biro, Beatrice; Berger, Sina; Praetzel, Leandra; Blodau, Christian


    The processes behind C-cycling in peatlands are important to understand for assessing the vulnerability of peatlands as carbon sinks under changing climate conditions. Especially boreal peatlands are likely to underlie strong alterations in the future. It is expected that C-pools that are directly influenced by vegetation and water table fluctuations can be easily destabilized. The CO2 efflux through respiration underlies autotrophic and heterotrophic processes that show different feedbacks on changing environmental conditions. In order to understand the respiration fluxes better for more accurate modelling and prognoses, the determination of the relative importance of different respiration sources is necessary. Earlier studies used e.g. exfoliation experiments, incubation experiments or modelling approaches to estimate the different respiration sources for the total ecosystem respiration (Reco). To further the understanding in this topic, I want to distinguish autotrophic and heterotrophic respiration using high temporal resolution measurements. The study site was selected along a hydrological gradient in a peatland in southern Ontario (Canada) and measurements were conducted from May to September 2015 once per month. Environmental controls (water table, soil temperature and soil moisture) that effect the respiration sources were recorded. In my study I used a Li-COR 6400XT and a Los Gatos greenhouse gas analyzer (GGA). Reco was determined by chamber flux measurements with the GGA, while simultaneously CO2 respiration measurements on different vegetation compartments like roots, leaves and mosses were conducted using the Li-COR 6400XT. The difference between Reco and autotrophic respiration equals heterotrophic respiration. After the measurements, the vegetation plots were harvested and separated for all compartments (leaves, roots, mosses, soil organic matter), dried and weighed. The weighted respiration rates from all vegetation compartments sum up to

  15. Southern Fine Particulate Monitoring Project

    Ashley Williamson


    This final project report presents experimental details, results and analysis of continuous onsite ambient fine particulate data at the North Birmingham sampling site during the October, 2001-September, 2002 study period.The host site for these measurement activities is the North Birmingham PM monitoring station by the Jefferson County Health Department in Birmingham, AL.The continuous data include PM{sub 2.5} mass concentrations measured by TEOM, particle sulfate using the R&P 8400S monitor, particle size distributions measured by SMPS and APS monitors, and PM{sub 2.5} light scattering extinction coefficient as measured by nephelometer. During the course of the project, measurement intercomparison data were developed for these instruments and several complementary measurements at the site. The report details the instrument set and operating procedures and describes the resulting data. Report subsections present an overview summary of the data, followed by detailed description of the systematic time behavior of PM{sub 2.5} and other specific particulate size fractions. Specific subsections are included for particle size distribution, light scattering, and particle sulfate data. The final subsection addresses application of the measurements to the practical questions of fine PM generation and transport, source attribution, and PM{sub 2.5} management strategies.

  16. Dans le tourbillon des particules

    Zito, Marco


    Accélérateurs géants, détecteurs complexes, particules énigmatiques... La physique subatomique peut sembler bien intimidante pour le novice. Et pourtant, qui n a jamais entendu parler du boson de Higgs et du CERN, le laboratoire européen où il a été découvert en 2012 ? Nul besoin d être un spécialiste pour comprendre de quoi il s agit. Aujourd hui, une théorie extraordinairement élégante, le Modèle Standard, décrit tous les résultats des expériences dans le domaine. Trente-sept particules élémentaires et quatre forces fondamentales : c est tout ce dont nous avons besoin pour expliquer la matière et l Univers ! Ce livre, destiné à un large public, raconte sans équations le long parcours qui a abouti au Modèle Standard. Ce parcours, parfois sinueux, a été entamé lorsque les Grecs anciens, et peut-être d autres avant eux, ont imaginé que la matière est composée de petites « billes ». Il faudra attendre plusieurs siècles pour qu on réalise que la matière, à l échelle micros...


    Particulate matter (PM), a component of air pollution has been epidemiologically associated with sudden deaths, cardiovascular and respiratory illnesses. The effects are more pronounced in patients with pre-existing conditions such as asthma, diabetes or obstructive pulmonary disorders. Clinical and experimental studies have historically focused on the cardiopulmonary effects of PM. However, since PM particles carry numerous biocontaminants that are capable of triggering free radical production and cytokine release, the possibility that PM may affect organs systems sensitive to oxidative stress must be considered. Four independent studies that summarize the neurochemical and neuropathological changes found in the brains of PM exposed animals are described here. These were recently presented at two 2007 symposia sponsored by the Society of Toxicology (Charlotte, NC) and the International Neurotoxicology Association (Monterey, CA). Particulates are covered with biocontaminants (e.g., endotoxins, mold, pollen) which convey free radical activity that can damage the lipids, nucleic acids, and proteins of target cells on contact and stimulate inflammatory cytokine release. Although, the historical focus of PM toxicity has been cardiopulmonary targets, it is now appreciated that inhaled nano-size (liver, kidneys, testes, lymph nodes) (Takenaka et aI

  18. A comprehensive study of the characterization of particulate matter emissions from a Delmarva broiler poultry operation

    Carter, Shannon E.

    within their total suspended and respirable regulatory categories are "inert" or nuisance, which infers that particles under this classification would not lead to any significant health problems. This is not the case with PM generated from a broiler poultry operation, which can carry with it a number of contaminants that have been proven to cause various health disorders from exposure. These classifications also apply to inhalable arsenic standards and are also questionable when determining whether arsenic concentrations in PM from a poultry operation are permissible. Arsenic oxidation state and speciation in PM10 and PM 2.5 was investigated using X-ray absorption spectroscopy (XAS) and X-ray fluorescence (XRF) spectroscopy. The results indicate that there is a mix of organic species present, as well as, oxidized As(V) and reduced As(III) in all samples analyzed. The main organic species found were in the form of Roxarsone, 4-hydroxy-3-aminophenylarsonic acid (HAPA), and dimethylarsinic acid (DMA(V)). This indicates that much of the organic form that was originally administered has degraded into more toxic by-products that are then becoming incorporated into airborne particulate matter.

  19. Seasonal and spatial variability of light absorption by suspended particles in the southern Baltic: A mathematical description

    Meler, Justyna; Ostrowska, Mirosława; Stoń-Egiert, Joanna; Zabłocka., Monika


    This paper analyses the relationships between the light absorption coefficients at 440 nm ap(440) for particles suspended in the surface waters of the southern Baltic Sea and the concentrations of some optically significant constituents in these waters. The analysis covers two main groups of particles: phytoplankton and non-algal. For this purpose we use the extensive database of optical measurements acquired from 2006 to 2013 during 40 cruises of r/v Oceania in various regions of the southern Baltic: open waters, coastal waters, the Gulf of Gdańsk, the Pomeranian Bay and river mouths. Expressions are derived for each of these regions to describe the seasonal variations of the dependence of the light absorption coefficients for phytoplankton aph(440) and non-algal particles aNAP(440) on concentrations of chlorophyll a (Tchla) and suspended particulate matter in sea water (SPM). With a knowledge of these dependences, one can determine the overall absorption coefficient for all suspended particles in any part of the Baltic Sea in particular seasons from known Tchla and SPM concentrations using the relationship ap(440) = aph(440) + aNAP(440) = f(Tchla, SPM). These dependences reflect the characteristics of a study area and season, and their application increases the accuracy of determination of the overall absorption properties of suspended particles and their main constituents as confirmed by statistical error reduction, e.g. standard error factor falls from 1.46 to 1.38. The relationships derived in this work can be applied in the local remote sensing algorithms used for monitoring the southern Baltic.

  20. Efficiency of different respiratory protective devices for removal of particulate and gaseous reactive oxygen species from welding fumes.

    Chen, Hsiu-Ling; Chung, Shih-Hsiang; Jhuo, Ming-Lin


    Ultraviolet (UV) light inherent to welding processes generates ozone (O(3)) with subsequent formation of reactive oxygen species (ROS) through photochemical reactions when UV light is present with O(3). This study aimed to determine the performance of filters used as respiratory protective devices by welding personnel to simultaneously mitigate particulate and gaseous inhalation hazards. Four respiratory protective devices were selected for this study, including a surgical facemask, a cotton-fabric facemask, an activated-carbon facemask, and an N95 respirator. The removal efficiencies for the particulates in welding fumes were all above 98%. For particulate-phase ROS, the removal efficiencies of the different respiratory protective devices ranged from 83.5% to 94.1%; however, the removal efficiencies for gaseous ROS were only 1.3% (active carbon facemask) to 21.1% (N95 respirator). The data indicated that the respiratory protective devices commercially available cannot block the passage of the gas-phase ROS found in welding fumes.