WorldWideScience

Sample records for respirable suspended particulates

  1. Exposure to carbon monoxide, respirable suspended particulates, and volatile organic compounds while commuting by bicycle

    International Nuclear Information System (INIS)

    Bevan, M.A.J.; Proctor, C.J.; Baker-Rogers, J.; Warren, N.D.

    1991-01-01

    A portable air sampling system has been used to assess exposures to various substances while commuting by bicycle in an urban area. The major source of pollutants in this situation is motor vehicle exhaust emissions. Carbon monoxide, measured by electrochemical detection, was found at peak concentrations in excess of 62 ppm, with mean values over 16 individual 35-mm journeys being 10.5 ppm. Respirable suspended particulates, averaged over each journey period, were found at higher concentrations (mean 130 μg m -3 ) than would be expected in indoor situations. Mean exposure to benzene (at 56 μg m -3 ) and other aromatic volatile organic compounds was also relatively high. The influence of wind conditions on exposure was found to be significant. Commuting exposures to carbon monoxide, respirable suspended particulates, and aromatic VOCs were found to be higher than exposures in a busy high street and on common parkland

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

    Science.gov (United States)

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

    2010-12-01

    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.

    Science.gov (United States)

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

    2010-12-15

    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. Exposure level of carbon monoxide and respirable suspended particulate in public transportation modes while commuting in urban area of Guangzhou, China

    Science.gov (United States)

    Chan, L. Y.; Lau, W. L.; Zou, S. C.; Cao, Z. X.; Lai, S. C.

    This study examined commuter exposure to respirable suspended particulate (PM 10 and PM 2.5) and carbon monoxide (CO) in public transportation modes in Guangzhou, China. During the sampling period, a total of 80 CO, 80 PM 10 and 56 PM 2.5 samples were conducted in four popular commuting modes (subway, air-conditioned bus, non-air-conditioned bus and taxi) while running in typical urban routes. The results show that the PM 10 as well as CO level is greatly influenced by the mode of transport. The highest mean PM 10 and CO level was obtained in a non-air-conditioned bus (203 μg m -3) and in an air-conditioned taxi (28.7 ppm) , respectively. Noticeably, the exposure levels in subway are lower than those in the roadway transports. The ventilation condition of the transport is also a crucial factor affecting the in-vehicle level. There was statistically significant difference of PM10 (ptransports, which provide service at regular intervals regardless of the time of day. The PM 2.5 inter-microenvironment variation is similar to the pattern of PM 10. The PM 2.5 to PM 10 ratio in the transports was high, ranging from 76% to 83%. The poor vehicle emission controls, poor vehicle maintenance, plus the slow moving traffic condition with frequent stops are believed to be the major causes of high in-vehicle levels in some public commuting trips.

  5. 40 CFR 230.21 - Suspended particulates/turbidity.

    Science.gov (United States)

    2010-07-01

    ... Impacts on Physical and Chemical Characteristics of the Aquatic Ecosystem § 230.21 Suspended particulates/turbidity. (a) Suspended particulates in the aquatic ecosystem consist of fine-grained mineral particles..., and man's activities including dredging and filling. Particulates may remain suspended in the water...

  6. Air pollution in Aleppo city, gases,suspended particulates

    International Nuclear Information System (INIS)

    Othman, I.; Sabra, Sh.; Al-Kharfan, K.

    1994-06-01

    Total suspended particulates measured by using High Volume Air Sampler. The Co and O 3 were measured during weekday and weekend. The concentration of all pollutants at city center are higher than other measured areas. (author). 10 figs., 10 tabs

  7. Elemental Concentration of Inhalable and Respirable Particulate ...

    African Journals Online (AJOL)

    20537 and respirable foam for I.O.M sampler. The elemental composition (Co, Ni, Zn, Cu, Fe, Pb, Cr, Mn and Cd) were analyzed by using Atomic Absorption Spectrophotometric (AAS). The data generated were subjected to descriptive analysis. In inhalable fraction,the enrichment factor ranged from 1-73.3 while in respirable ...

  8. Atmospheric trace metal concentrations in Suspended Particulate ...

    African Journals Online (AJOL)

    The air particulate samples were collected from the kitchens, living rooms and outdoor environment of five households in the community. The quantification of the trace metals was done using Atomic Absorption spectrometry method, employing HNO based wet digestion. High baseline concentration of SPMwere obtained ...

  9. Nature of suspended particulate matter and concentrations of heavy ...

    African Journals Online (AJOL)

    The concentrations of metals in bottom sediment in the Tanzanian waters of Lake Victoria and the nature of suspended particulate matter (SPM) were analysed. The objective of the study was to compare levels of metals in sediment from different locations and to establish their sources. Metal concentrations were higher in ...

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

    Science.gov (United States)

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

    2016-07-01

    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

  11. Suspended particulate matter in dwellings - the impact of tobacco smoking

    Energy Technology Data Exchange (ETDEWEB)

    Revsbech, P.; Korsgaard, J.; Lundqvist, G.R.

    1987-01-01

    The indoor concentration of suspended particulate matter (SPM) was measured in 44 retrofitted and tight dwellings, which had electric cooking and were central heated and where the basic ventilation rate in median amounted 0.23 air changes per hour as measured with a tracer dilution method. The indoor concentration of SPM was in medium 230 ..mu..g/m/sup 3/ with a strong correlation to the tobacco consumption (r/sub s/ = 0.716), but with no correlation to the frequency of airing or the basic ventilation rate. Tobacco smoking seems to be the main indoor source of SPM in contemporary dwellings. The importance of these findings is underlined by epidemiologic studies on passive smoking and health. Air quality standards for the ambient air are based on certain risk groups such as infants, children, persons with chronic obstructive lung disorders, and indoor air standards should be based on the same concepts of health protection.

  12. Status of Suspended Particulate Matters Pollution at Traditional Markets in Makassar City

    Science.gov (United States)

    Suryani, Sri; Fahrunnisa

    2018-03-01

    Research on the status of suspended particulate matters pollution in four traditional markets located in Makassar city has been done. The purpose of this research is to know the air quality in the traditional market areas, especially caused by suspended particulate matters. The background of this research is because traders who trade in traditional markets generally peddle their goods along dusty roads and suspended particulate matters in dust can be inhaled when the vehicle passes. These suspended particulate matters pollutant can cause lung diseases. The results showed that the level of suspended particulate matters pollution fluctuates every year depending on the local wind speed, humidity, and temperature. Research results also showed the values were over the standard value according to the governor of South Sulawesi regulation.

  13. Capturing Flow-weighted Water and Suspended Particulates from Agricultural Canals During Drainage Events.

    Science.gov (United States)

    Bhadha, Jehangir H; Sexton, Anne; Lang, Timothy A; Daroub, Samira H

    2017-11-07

    The purpose of this study is to describe the methods used to capture flow-weighted water and suspended particulates from farm canals during drainage discharge events. Farm canals can be enriched by nutrients such as phosphorus (P) that are susceptible to transport. Phosphorus in the form of suspended particulates can significantly contribute to the overall P loads in drainage water. A settling tank experiment was conducted to capture suspended particulates during discrete drainage events. Farm canal discharge water was collected in a series of two 200 L settling tanks over the entire duration of the drainage event, so as to represent a composite subsample of the water being discharged. Imhoff settling cones are ultimately used to settle out the suspended particulates. This is achieved by siphoning water from the settling tanks via the cones. The particulates are then collected for physico-chemical analyses.

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

    Digital Repository Service at National Institute of Oceanography (India)

    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...

  15. Long-term measurements of respirable sulfates and particulates inside and outside homes

    Energy Technology Data Exchange (ETDEWEB)

    Spengler, J D; Dockery, D W; Turner, W A; Wolfson, J M; Ferris, B G

    1981-01-01

    To better understand the health effects of air pollution, the results of extensive indoor and outdoor measurements of mass respirable particulates and water-soluble respirable particulates are analyzed. The measurements were taken in six U.S. citiesPortage, Wis./ Topeka, Kans./ Kingston/Harriman, Tenn./ Watertown, Mass./ St. Louis, Mo./ and Steubenville, Ohio. Results indicated that the major source of indoor air pollution is cigarette smoke, which contributes about 20

  16. 78 FR 22501 - Designation of Areas for Air Quality Planning Purposes; State of Nevada; Total Suspended Particulate

    Science.gov (United States)

    2013-04-16

    ... Areas for Air Quality Planning Purposes; State of Nevada; Total Suspended Particulate AGENCY... designations for total suspended particulate within the State of Nevada because the designations are no longer necessary. These designations relate to the attainment or unclassifiable areas for total suspended...

  17. Respirator use and its impact on particulate matter exposure in aluminum manufacturing facilities.

    Science.gov (United States)

    Liu, Sa; Noth, Elizabeth; Eisen, Ellen; Cullen, Mark R; Hammond, Katharine

    2018-05-31

    Objectives As part of a large epidemiologic study of particulate health effect, this study aimed to report respirator use among total particulate matter (TPM) samples collected in a major aluminum manufacturing company from 1966‒2013 and evaluate the impact of respirator-use adjustment on exposure estimation. Methods Descriptive analyses were performed to evaluate respirator use across facilities and by facility type and job. Protection factors were applied to TPM measurements for recorded respirator use. Estimated TPM exposure for each job ‒ before and after respirator-use adjustment ‒ were compared to assess the impact of adjustment on exposure estimation. Results Respirator use was noted for 37% of 12 402 full-shift personal TPM samples. Measured TPM concentration ranged from less than detectable to 8220 mg/m3, with arithmetic mean, median and standard deviation being 10.6, 0.87 and 130 mg/m 3 , respectively. Respirators were used more often in smelting facilities (52% of TPM measurements) than in fabricating (17%) or refinery facilities (28%) (Pfacilities were subject to respirator-use adjustment, whereas it was 20% and 70% in fabricating and refinery facilities, respectively. Applying protection factors to TPM measurements significantly reduced estimated job mean TPM exposures and changed exposure categories in these facilities, with larger impact in smelting than fabricating facilities. Conclusions Respirator use varied by time, facility and job. Adjusting respirator use resulted in differential impact in smelting and fabricating facilities, which will need to be incorporated into ongoing epidemiologic studies accordingly.

  18. Particulate Respirators Functionalized with Silver Nanoparticles Showed Excellent Real-Time Antimicrobial Effects against Pathogens.

    Science.gov (United States)

    Zheng, Clark Renjun; Li, Shuai; Ye, Chengsong; Li, Xinyang; Zhang, Chiqian; Yu, Xin

    2016-07-05

    Particulate respirators designed to filtrate fine particulate matters usually do not possess antimicrobial functions. The current study aimed to functionalize particulate respirators with silver nanoparticles (nanosilver or AgNPs), which have excellent antimicrobial activities, utilizing a straightforward and effective method. We first enhanced the nanosilver-coating ability of nonwoven fabrics from a particulate respirator through surface modification by sodium oleate. The surfactant treatment significantly improved the fabrics' water wet preference where the static water contact angles reduced from 122° to 56°. Both macroscopic agar-plate tests and microscopic scanning electron microscope (SEM) characterization revealed that nanosilver functionalized fabrics could effectively inhibit the growth of two model bacterial strains (i.e., Staphylococcus aureus and Pseudomonas aeruginosa). The coating of silver nanoparticles would not affect the main function of particulate respirators (i.e., filtration of fine air-borne particles). Nanosilver coated particulate respirators with excellent antimicrobial activities can provide real-time protection to people in regions with severe air pollution against air-borne pathogens.

  19. Daily variability of suspended particulate concentrations and yields and their effect on river particulates chemistry

    Directory of Open Access Journals (Sweden)

    M. Meybeck

    2015-03-01

    Full Text Available Daily total suspended solids concentrations (TSS, mg L-1, yields (Y, kg day-1 km-2 and runoff (q, L s-1 km-2 in world rivers are described by the median (C50, the upper percentile (C99, the discharge-weighted average concentrations (C*, and by their corresponding yields (Y50, Y99, Y* and runoff (q*, q50, q99. These intra-station descriptors range over two to six orders of magnitude at a given station. Inter-station variability is considered through three sets of dimensionless metrics: (i q*/q50, C*/C50 and Y*/Y50, defining the general temporal variability indicators, and q99/q50, C99/C50 and Y99/Y50, defining the extreme variability indicators; (ii river flow duration (W2 and flux duration (M2 in 2% of time; and (iii the truncated rating curve exponent (b50sup of the C vs q relationship for the upper flows. The TSS and Y variability, measured on US, French and world rivers, are first explained by hydrological variability through the b50sup metric, the variability amplifier, then by basin size, erodibility, relief and lake occurrence. Yield variability is the product of runoff variability × TSS variability. All metrics are considerably modified after river damming. The control of river particulate matter (RPM composition by TSS or yields depends on the targeted component. For major elements (Al, Fe, Mn, Ti, Si, Ca, Mg, Na, K, the average RPM chemistry is not dependent on C* and Y* in most world hydroregions, except in the tropical hydrobelt where it is controlled by basin relief. By contrast, the particulate organic carbon content (POC, as a percentage of RPM is inversely correlated to TSS concentrations for (i intra-station measurements in any hydroregion, and (ii inter-station average POC and TSS figures in world rivers. TSS controls heavy metal content (ppm in highly contaminated basins (e.g. Cd in the Seine vs the Rhone, and total metal concentration (ng/L in all cases. Relations between RPM composition and TSS should be taken into account

  20. Characterization of respirable mine dust and diesel particulate matter

    CSIR Research Space (South Africa)

    Mahlangu, Vusi J

    2015-11-01

    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...

  1. Deposition of Suspended Fine Particulate Matter in a Library

    Czech Academy of Sciences Publication Activity Database

    Smolík, Jiří; Mašková, Ludmila; Zíková, Naděžda; Ondráčková, Lucie; Ondráček, Jakub

    2013-01-01

    Roč. 1, 3 April (2013) ISSN 2050-7445 R&D Projects: GA MK DF11P01OVV020 Keywords : fine particulate matter * deposition * brownian diffusion Subject RIV: CF - Physical ; Theoretical Chemistry http://www.heritagesciencejournal.com/content/1/1/7

  2. Amino sugars in suspended particulate matter from the Bay

    Indian Academy of Sciences (India)

    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 ...

  3. Spatial Distribution of Suspended Particulate Matter in Mtwapa ...

    African Journals Online (AJOL)

    ... in the three sites; it accounts for a mean of 61% ±20 in Ramisi, 97% ±0.7 in Shirazi and 65% ±29 in Mtwapa. These high detritus levels are expected because of the allochthonous supply of particulate material by the river in Ramisi and the contribution from mangroves, which fringe the banks of the estuary and the creeks.

  4. Suspended particulate studies over the Madeira Abyssal Plain

    International Nuclear Information System (INIS)

    Simpson, W.R.

    1987-01-01

    Various aspects relating to suspended matter over the Madeira Abyssal Plain are discussed. Special attention is paid to the nepheloid layer including resuspension and transport processes; time variabilities in particle concentrations and fluxes; particle morphology, microbiology and chemical composition; phase association of metals. Also, tentative predictions of the behaviour of some radionuclides are made based on theory and data on rare earth elements. Instrumentation developed for the project is detailed - the deep water particle sampler. (author)

  5. Characteristic of ambient airborne and respirable particulate around a non formal industrial area

    International Nuclear Information System (INIS)

    Muhayatun Santoso; Diah Dwiana Lestiani; Mariana Marselina; Rita Mukhtar

    2016-01-01

    Characterization of airborne particulate matter and respirable particulate in Parung Panjang district especially on surrounding non formal used batteries industrial area has been carried out to follow up the previous results with respect to high concentrations of lead detected in Serpong area. Sampling of airborne particulate matter in Parung Panjang was conducted using Gent stacked filter unit sampler, while the respirable particulate matter samples collected using personal dust sampler in Parung Panjang as a non formal Industrial area and Sukarasa village as a control, during 2011-2012. The concentration of masses were determined gravimetrically, while for elemental concentrations by X-Ray based methods. The average of mass concentration of air ambient PM 2.5 and PM 10 in Parung Panjang were 27.3 ± 13.7 and 77.5 ± 17.1 μg.m -3 , respectively. While the average concentration of respirable particulate in non formal industrial and control areas were 260 ± 233 and 82 ± 38 μg.m -3 , respectively. The percentage of average Pb concentration in PM 2.5 and PM 2.5-10 were contribute up to 45 and 10 % of the mass concentration, respectively. The maximum percentage concentration of Pb in respirable particulate in industrial and control area were 12.11 and 0.27 %, respectively. These results showed that the Pb concentrations in respirable particulate in industrial area were significantly tens times higher than in the control area. The high concentration of Pb in Parung Panjang was the main key element came from the used lead battery industry and one of pollutant source that contributed to the Pb pollution in Serpong area. (author)

  6. Observations of a narrow zone of high suspended particulate matter (SPM) concentrations along the Dutch coast

    NARCIS (Netherlands)

    van der Hout, C.M.; Gerkema, T.; Nauw, J.J.; Ridderinkhof, H.

    2015-01-01

    The objective of the study described in this paper is to localize the transport path of suspended particulate matter (SPM) in the Dutch coastal zone in the southern North Sea. It is known that a large mass of SPM is transported northward from the Strait of Dover, which is however mostly hidden from

  7. Monitoring of total suspended air particulate in the ambient air of ...

    African Journals Online (AJOL)

    Monitoring of total suspended air particulate in the ambient air of welding, car painting and. V. C. IKAMAISE, I. B. OBIOH, I. E. OFOZIE, F. A. AKEREDOLU. Full Text: EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT · http://dx.doi.org/10.4314/gjpas.v7i4.16316.

  8. Floc size and aspects of flocculation processes of suspended particulate matter in the North Sea area

    NARCIS (Netherlands)

    Chen, S.

    1995-01-01

    Investigations on the size of suspended particulate matter in the North Sea and two adjacent estuaries were carried out using an in situ technique: image analysis of photographs from an underwater camera system. The results obtained from such an in situ method gave a new knowledge on the size

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

    CSIR Research Space (South Africa)

    Terblanche, APS

    1995-06-01

    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...

  10. Vertical transport of suspended particulate trace elements in the North Atlantic Ocean

    International Nuclear Information System (INIS)

    Kuss, J.; Kremling, K.; Scholten, J.

    1999-01-01

    Suspended marine particles play a key role in the exchange processes between rapidly sinking particles and seawater because of their large surface area and long residence times. They are involved in the transport processes of rapidly sinking particles (∼ 100 m/day) through aggregation and disaggregation. This mechanism results in a net downward transport of suspended particulate trace elements (TE). To provide more information to these processes TE in suspended particulate material (SPM) have been measured on three cruises from 1995 to 1997 along 20 deg. W using a large volume in situ filtration between 25 m and 4150 m depth in addition to particle flux measurements with sediment traps. These studies were performed under the framework of German JGOFS

  11. Suspended marine particulate proteins in coastal and oligotrophic waters

    Science.gov (United States)

    Bridoux, Maxime C.; Neibauer, Jaqui; Ingalls, Anitra E.; Nunn, Brook L.; Keil, Richard G.

    2015-03-01

    Metaproteomic analyses were performed on suspended sediments collected in one coastal environment (Washington margin, Pacific Ocean, n = 5) and two oligotrophic environments (Atlantic Ocean near BATS, n = 5, and Pacific Ocean near HOTS, n = 5). Using a database of 2.3 million marine proteins developed using the NCBI database, 443 unique peptides were detected from which 363 unique proteins were identified. Samples from the euphotic zone contained on average 2-3x more identifiable proteins than deeper waters (150-1500 m) and these proteins were predominately from photosynthetic organisms. Diatom peptides dominate the spectra of the Washington margin while peptides from cyanobacteria, such as Synechococcus sp. dominated the spectra of both oligotrophic sites. Despite differences in the exact proteins identified at each location, there is good agreement for protein function and cellular location. Proteins in surface waters code for a variety of cellular functions including photosynthesis (24% of detected proteins), energy production (10%), membrane production (9%) and genetic coding and reading (9%), and are split 60-40 between membrane proteins and intracellular cytoplasmic proteins. Sargasso Sea surface waters contain a suite of peptides consistent with proteins involved in circadian rhythms that promote both C and N fixation at night. At depth in the Sargasso Sea, both muscle-derived myosin protein and the muscle-hydrolyzing proteases deseasin MCP-01 and metalloprotease Mcp02 from γ-proteobacteria were observed. Deeper waters contain peptides predominately sourced from γ-proteobacteria (37% of detected proteins) and α-proteobacteria (26%), although peptides from membrane and photosynthetic proteins attributable to phytoplankton were still observed (13%). Relative to surface values, detection frequencies for bacterial membrane proteins and extracellular enzymes rose from 9 to 16 and 2 to 4% respectively below the thermocline and the overall balance between

  12. Investigation of the suspended particulate matter in the Asian region for seven years

    International Nuclear Information System (INIS)

    Harasawa, Susumu

    1999-01-01

    Activities of the workshops for the investigation of environmental materials by NAA (Neutron Activation Analysis) methods during 1992 to 1997 held in Jakarta are briefly reported. Detail of selection of the theme (investigation of the suspended particulate matter in the Asian region by NAA), the results of the inter-comparison for the analysis using NIES No. 8 reference standard samples (vehicle exhaust particulate) are presented. In conclusion, systematically accumulated data on the environmental substances and their time variations measured and analyzed by INAA (Instrumental Neutron Activation Analysis) method give useful information on pollution problems and air movement in the Asia region. (S. Ohno)

  13. Investigation of the suspended particulate matter in the Asian region for seven years

    Energy Technology Data Exchange (ETDEWEB)

    Harasawa, Susumu [Institute for Atomic Energy, Rikkyo Univ., Yokosuka, Kanagawa (Japan)

    1999-10-01

    Activities of the workshops for the investigation of environmental materials by NAA (Neutron Activation Analysis) methods during 1992 to 1997 held in Jakarta are briefly reported. Detail of selection of the theme (investigation of the suspended particulate matter in the Asian region by NAA), the results of the inter-comparison for the analysis using NIES No. 8 reference standard samples (vehicle exhaust particulate) are presented. In conclusion, systematically accumulated data on the environmental substances and their time variations measured and analyzed by INAA (Instrumental Neutron Activation Analysis) method give useful information on pollution problems and air movement in the Asia region. (S. Ohno)

  14. Trace elements in suspended particulate matter and liquid fraction of the Arno River waters

    International Nuclear Information System (INIS)

    Capannesi, G.; Cecchi, A.; Mando, P.A.

    1984-01-01

    The concentrations of 46 elements along the course of the Arno River (Tuscany, Italy) have been determined by means of Instrumental Neutron Activation Analysis. Both suspended particulate matter and liquid fraction have been investigated. No chemical treatment has been performed on the samples, either before or after irradiation. Anticoincidence techniques have been employed in the γ spectroscopy. Results are briefly discussed also from a methodological point of view. 4 references, 16 figures, 2 tables

  15. Generation of hydroxyl radicals by urban suspended particulate air matter. The role of iron ions

    Science.gov (United States)

    Valavanidis, Athanasios; Salika, Anastasia; Theodoropoulou, Anna

    Recent epidemiologic studies showed statistical associations between particulate air pollution in urban areas and increased morbidity and mortality, even at levels well within current national air quality standards. Inhalable particulate matter (PM 10) can penetrate into the lower airways where they can cause acute and chronic lung injury by generating toxic oxygen free radicals. We tested inhalable total suspended particulates (TSP) from the Athens area, diesel and gasoline exhaust particles (DEP and GED), and urban street dusts, by Electron Paramagnetic Resonance (EPR). All particulates can generate hydroxyl radicals (HO ṡ), in aqueous buffered solutions, in the presence of hydrogen peroxide. Results showed that oxidant generating activity is related with soluble iron ions. Leaching studies showed that urban particulate matter can release large amounts of Fe 3+ and lesser amounts of Fe 2+, as it was shown from other studies. Direct evidence of HO ṡ was confirmed by spin trapping with DMPO and measurement of DMPO-OH adduct by EPR. Evidence was supported with the use of chelator (EDTA), which increases the EPR signal, and the inhibition of the radical generating activity by desferrioxamine or/and antioxidants ( D-mannitol, sodium benzoate).

  16. 78 FR 69361 - Development of Inward Leakage Standards for Half-Mask Air-Purifying Particulate Respirators

    Science.gov (United States)

    2013-11-19

    ... DEPARTMENT OF HEALTH AND HUMAN SERVICES 42 CFR Part 84 [Docket No. CDC-2013-0017; NIOSH-250] Development of Inward Leakage Standards for Half-Mask Air- Purifying Particulate Respirators AGENCY: Centers... regarding the development of inward leakage performance standards for half-mask air- purifying particulate...

  17. Evaluation of total suspended particulate matter in some urban and industrial cities of Pakistan

    International Nuclear Information System (INIS)

    Qadir, M.A.; Iqbal, M.Z.

    1996-01-01

    Environmental studies are very important as the living beings depend greatly on the conditions of the environment. Air is an important component of the environment, which greatly affects the health of humans, animals and plants. Environmental problems in Pakistan are growing with the rise in total sectorial growth in population, economy and industrialization. In connection with atmospheric pollution, measurement of the total suspended particulate matter (TSP) in the urban atmosphere of Lahore, Faisalabad, Rawalpindi, Islamabad, Wah Cantt. and Khanispur (background area) has been carried out and compared to that of U.S. Environmental Protection Agency Standards. (author)

  18. Experimental study on kinetics oil oil-suspended particulate matter aggregation

    International Nuclear Information System (INIS)

    Sun, J.; Environment Canada, Ottawa, ON; Khelifa, A.; Wang, Z.; Brown, C.; Fieldhouse, B.; Yang, C.; Zheng, X.; Wong, S.; So, L.C.

    2009-01-01

    Past studies of oil spills have shown that oil suspended particulate matter aggregates (OSAs) play a role in enhancing the natural cleansing of oiled shorelines. OSAs result from aggregation between suspended oil droplets and suspended particulate matter (SPM) in aquatic environments. During this process, oil dispersion into the water column is significantly increased since the surface of the oil droplet is surrounded by sediment particles. In addition, the accelerated biodegradation of the oil can be attributed to the greater oil-water contact area. This study focused on the kinetic aspects of OSA formation, with particular reference to the time scale of this process and its significance to oil dispersion following oil spills in water. A laboratory study was conducted to measure the time scale of OSA formation and its variations with mixing conditions. A reciprocating shaker and various oil/sediment mixtures were used to prepare the OSAs. Standard reference material 1941b was used as the natural sediment mixed with Arabian medium crude and artificial seawater under various mixing energies. The sediment-to-oil ratio remained constant for all experiments. Gas chromatography-flame ionization detection (GC-FID) analysis was used to measure the total petroleum hydrocarbons (TPH) trapped in negatively buoyant OSAs. Results showed that the TPH in OSAs increased exponentially with shaking time and reached an equilibrium value within 3 hours. The equilibrium decreased from 3 hours to 1.3 hours when the shaking rate increased from 2.0 to 2.3 Hz. It was concluded that high mixing energy enhances OSA formation and shortens the time for OSA formation. 42 refs., 6 tabs., 5 figs

  19. Experimental study on kinetics oil oil-suspended particulate matter aggregation

    Energy Technology Data Exchange (ETDEWEB)

    Sun, J. [Ocean Univ. of China, Qingdoa (China). Environmental Science and Engineering Inst.; Environment Canada, Ottawa, ON (Canada). Emergencies Science and Technology Section, Emergencies, Operational Analytical Laboratories and Research Support Division; Khelifa, A.; Wang, Z.; Brown, C.; Fieldhouse, B.; Yang, C. [Environment Canada, Ottawa, ON (Canada). Emergencies Science and Technology Section, Emergencies, Operational Analytical Laboratories and Research Support Division; Zheng, X. [Ocean Univ. of China, Qingdoa (China). Environmental Science and Engineering Inst.; Wong, S. [Ottawa Univ., ON (Canada). Dept. of Chemistry; So, L.C. [Waterloo Univ., ON (Canada). Faculty of Engineering

    2009-07-01

    Past studies of oil spills have shown that oil suspended particulate matter aggregates (OSAs) play a role in enhancing the natural cleansing of oiled shorelines. OSAs result from aggregation between suspended oil droplets and suspended particulate matter (SPM) in aquatic environments. During this process, oil dispersion into the water column is significantly increased since the surface of the oil droplet is surrounded by sediment particles. In addition, the accelerated biodegradation of the oil can be attributed to the greater oil-water contact area. This study focused on the kinetic aspects of OSA formation, with particular reference to the time scale of this process and its significance to oil dispersion following oil spills in water. A laboratory study was conducted to measure the time scale of OSA formation and its variations with mixing conditions. A reciprocating shaker and various oil/sediment mixtures were used to prepare the OSAs. Standard reference material 1941b was used as the natural sediment mixed with Arabian medium crude and artificial seawater under various mixing energies. The sediment-to-oil ratio remained constant for all experiments. Gas chromatography-flame ionization detection (GC-FID) analysis was used to measure the total petroleum hydrocarbons (TPH) trapped in negatively buoyant OSAs. Results showed that the TPH in OSAs increased exponentially with shaking time and reached an equilibrium value within 3 hours. The equilibrium decreased from 3 hours to 1.3 hours when the shaking rate increased from 2.0 to 2.3 Hz. It was concluded that high mixing energy enhances OSA formation and shortens the time for OSA formation. 42 refs., 6 tabs., 5 figs.

  20. Consumption-based Total Suspended Particulate Matter Emissions in Jing-Jin-Ji Area of China

    Science.gov (United States)

    Yang, S.; Chen, S.; Chen, B.

    2014-12-01

    The highly-industrialized regions in China have been facing a serious problem of haze mainly consisted of total suspended particulate matter (TSPM), which has attracted great attention from the public since it directly impairs human health and clinically increases the risks of various respiratory and pulmonary diseases. In this paper, we set up a multi-regional input-output (MRIO) model to analyze the transferring routes of TSPM emissions between regions through trades. TSPM emission from particulate source regions and sectors are identified by analyzing the embodied TSPM flows through monetary flow and carbon footprint. The track of TSPM from origin to end via consumption activities are also revealed by tracing the product supply chain associated with the TSPM emissions. Beijing-Tianjin-Hebei (Jing-Jin-Ji) as the most industrialized area of China is selected for a case study. The result shows that over 70% of TSPM emissions associated with goods consumed in Beijing and Tianjin occurred outside of their own administrative boundaries, implying that Beijing and Tianjin are net embodied TSPM importers. Meanwhile, 63% of the total TSPM emissions in Hebei Province are resulted from the outside demand, indicating Hebei is a net exporter. In addition, nearly half of TSPM emissions are the by-products related to electricity and heating supply and non-metal mineral products in Jing-Jin-Ji Area. Based on the model results, we provided new insights into establishing systemic strategies and identifying mitigation priorities to stem TSPM emissions in China. Keywords: total suspended particulate matter (TSPM); urban ecosystem modeling; multi-regional input-output (MRIO); China

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

    Science.gov (United States)

    Cho, Hyun-Woo; Yoon, Chung-Sik

    2012-10-01

    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

  2. Air pollution study in dust and suspended particulate materials in phosphate mines and Palmyra city

    International Nuclear Information System (INIS)

    Othman, I.; Sabra, Sh.; Al-Kharfan, K.

    1994-01-01

    A study was made during July 1991 in the phosphate mines (Khnifees and Sharqeh) and Palmyra city, total suspended particulate materials (SPM) were collected from these mines and Palmyra city. Also SPM of less than 10μ distribution were measured. The quantity of dust fall in phosphate mines and Palmyra city was estimated. The results show increase in the concentrations, especially the SPM of more than 10μ diameter. The highest value was in Khnifees administration and Sharqeh laboratory. Active traffic in Palmyra streets raised the SPM less than 10μ to a double value in Khnifees and Sharqeh villages. The quantity of dust-fall in mines area agrees with the concentration of total SPM. (author). 2 figs., 2 tabs

  3. Environmental toxicology: Acute effects of suspended particulate matter (dust on hematological indices of albino rats

    Directory of Open Access Journals (Sweden)

    V.O. Ogugbuaja

    2004-12-01

    Full Text Available The elemental contents of suspended particulate matter (dust samples from Maiduguri, Nigeria, were determined which showed appreciably high levels for especially Pb, Fe, Cu, Zn, K, Ca, and. Na. Wister albino rats were exposed to graded doses of phosphate buffered saline carried dust particles. The hematological indices of the exposed rats were examined on days 10, 20, 30, and 60 post administrations. White blood cell, red blood cell and hemoglobin counts peaked between days 20 and 30. This observation was markedly so for the higher doses, 1000 and 2000 mg/kg, in contrast to the 500 mg/kg dose. The platelet count however indicated a gradual increase within the study period. Observed changes for these indices from the control values were found significant at 99% confidence level. Possible inhalatory problems are thus anticipated from prolonged accumulation of the dust in the respiratory system.

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

    Energy Technology Data Exchange (ETDEWEB)

    Hausstein, H.

    2008-11-06

    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.)

  5. Characterization and radionuclides sorption of suspended particulate matters in freshwater according to their settling kinetics

    International Nuclear Information System (INIS)

    Brach-Papa, C.; Boyer, P.; Amielh, M.; Anselmet, F.

    2004-01-01

    In freshwater, the transfers of radionuclides depend both on exchanges between liquid and solid phases and on mass transfers between suspended matter and bottom sediment. Whereas the former ones depend on chemical processes (such as sorption/desorption, complexation, the latter ones are regulated by hydrological and sedimentary considerations (dispersion, erosion, deposit closely related to the interactions between flow, suspended matter and bed sediment. Some of our previous studies highlight the need to consider the matter heterogeneity and its specific sediment dynamics to correctly report the inhomogeneity of fluxes in time and in space. These considerations lead us to develop experimental methods to distinguish the different matter classes, present in natural water, mainly according to their erosion threshold and settling kinetics. In this context, this paper presents the experimental protocol TALISMEN to characterize a natural bulk suspension according the identification of its main settling kinetics groups. In a first step, this identification is achieved by the use of a settling tank, that allows the monitoring of the suspended solid concentration at various depths, combined to a vertical mono-dimensional settling model applying a multi-class approach. In a second step, the particle groups are isolated and their physico-chemical properties are determined ( i.e mineral composition, specific surface area, particulate organic carbon, in order to fully characterized them. In a last one, the sorption property of each group toward radionuclides is determined by the measurements of its distribution coefficients (Kd). The results confirm the interest to consider these heterogeneities for the modelling of the radionuclides transfer in freshwater. From one group to other, these heterogeneities appear at two levels: 1) their sediment dynamics and 2) their radionuclides sorption properties. These conclusions can be equally applying to others xenobiotics as heavy metals

  6. Polybrominated diphenyl ethers in influents, suspended particulate matter, sediments, sewage treatment plant and effluents and biota from the Netherlands

    NARCIS (Netherlands)

    Boer, de J.; Wester, P.G.; Horst, van der A.; Leonards, P.E.G.

    2003-01-01

    Polybrominated diphenyl ethers (PBDEs) have been determined in 133 samples of suspended particulate matter (SPM), sediments, sewage treatment plant (STP) influents and effluents, fish and mussels from various locations in The Netherlands, as a part of a large Dutch national study on estrogenic

  7. Predicting runoff of suspended solids and particulate phosphorus for selected Louisiana soils using simple soil tests.

    Science.gov (United States)

    Udeigwe, Theophilus K; Wang, Jim J; Zhang, Hailin

    2007-01-01

    This study was conducted to evaluate the relationships among total suspended solids (TSS) and particulate phosphorus (PP) in runoff and selected soil properties. Nine Louisiana soils were subjected to simulated rainfall events, and runoff collected and analyzed for various parameters. A highly significant relationship existed between runoff TSS and runoff turbidity. Both runoff TSS and turbidity were also significantly related to runoff PP, which on average accounted for more than 98% of total P (TP) in the runoff. Runoff TSS was closely and positively related to soil clay content in an exponential fashion (y=0.10e0.01x, R2=0.91, Psoil electrical conductivity (EC) (y=0.02 x(-3.95), R2=0.70, Psoil suspension turbidity" (SST) which measures turbidity in a 1:200 soil/water suspension, exhibited highly significant linear relationships with runoff TSS (y=0.06x-4.38, R2=0.82, Psoil clay content and EC in a multiple regression, suggesting that SST was able to account for the integrated effect of clay content and electrolytic background on runoff TSS. The SST test could be used for assessment and management of sediment and particulate nutrient losses in surface runoff.

  8. Health Outcomes of Exposure to Biological and Chemical Components of Inhalable and Respirable Particulate Matter.

    Science.gov (United States)

    Morakinyo, Oyewale Mayowa; Mokgobu, Matlou Ingrid; Mukhola, Murembiwa Stanley; Hunter, Raymond Paul

    2016-06-14

    Particulate matter (PM) is a key indicator of air pollution and a significant risk factor for adverse health outcomes in humans. PM is not a self-contained pollutant but a mixture of different compounds including chemical and biological fractions. While several reviews have focused on the chemical components of PM and associated health effects, there is a dearth of review studies that holistically examine the role of biological and chemical components of inhalable and respirable PM in disease causation. A literature search using various search engines and (or) keywords was done. Articles selected for review were chosen following predefined criteria, to extract and analyze data. The results show that the biological and chemical components of inhalable and respirable PM play a significant role in the burden of health effects attributed to PM. These health outcomes include low birth weight, emergency room visit, hospital admission, respiratory and pulmonary diseases, cardiovascular disease, cancer, non-communicable diseases, and premature death, among others. This review justifies the importance of each or synergistic effects of the biological and chemical constituents of PM on health. It also provides information that informs policy on the establishment of exposure limits for PM composition metrics rather than the existing exposure limits of the total mass of PM. This will allow for more effective management strategies for improving outdoor air quality.

  9. Health Outcomes of Exposure to Biological and Chemical Components of Inhalable and Respirable Particulate Matter

    Directory of Open Access Journals (Sweden)

    Oyewale Mayowa Morakinyo

    2016-06-01

    Full Text Available Particulate matter (PM is a key indicator of air pollution and a significant risk factor for adverse health outcomes in humans. PM is not a self-contained pollutant but a mixture of different compounds including chemical and biological fractions. While several reviews have focused on the chemical components of PM and associated health effects, there is a dearth of review studies that holistically examine the role of biological and chemical components of inhalable and respirable PM in disease causation. A literature search using various search engines and (or keywords was done. Articles selected for review were chosen following predefined criteria, to extract and analyze data. The results show that the biological and chemical components of inhalable and respirable PM play a significant role in the burden of health effects attributed to PM. These health outcomes include low birth weight, emergency room visit, hospital admission, respiratory and pulmonary diseases, cardiovascular disease, cancer, non-communicable diseases, and premature death, among others. This review justifies the importance of each or synergistic effects of the biological and chemical constituents of PM on health. It also provides information that informs policy on the establishment of exposure limits for PM composition metrics rather than the existing exposure limits of the total mass of PM. This will allow for more effective management strategies for improving outdoor air quality.

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

    Directory of Open Access Journals (Sweden)

    Carlos Augusto França Schettini

    2010-03-01

    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

  11. Suspended particulate matter flocculation in a natural tidal wetland located in the San Francisco Estuary

    Science.gov (United States)

    Saraceno, J.; Bergamaschi, B. A.; Wright, S. A.; Boss, E.; Downing, B. D.; Fleck, J.; Ganju, N. K.

    2011-12-01

    Suspended mineral and algal particles together comprise suspended particulate matter (SPM). The SPM size distribution influences the quantity and color of light penetration and the adsorption and transport of contaminants such as pesticides and metals. It is widely known that interaction with wetlands alters the size distribution and quality of particles through local primary production, differential settling and particle aggregation, however, our understanding of how tidal wetland processes affect SPM quantity and size spectra has been hampered by the difficulty of directly observing these parameters at tidal time scales. To evaluate how SPM concentration and size varied over tidal time scales and to better understand the relationship between organic matter and sediment characteristics, simultaneous measurements of dissolved organic matter, SPM concentration and organic content as well as in situ surrogates of particle concentration (turbidity, particulate attenuation, volume concentration) and particle size (laser diffraction) were carried out with measurements of current velocity (acoustic Doppler velocity meter) in the main channel of Brown's Island located in the western San Joaquin/Sacramento River Delta, CA. The study period coincided with high estuary sediment levels following a significant precipitation runoff event. In the Brown Island wetland, particle concentration and size dynamics were tied to variations in water level and velocity. Turbidity and attenuation covaried with the volume concentration of particles smaller than 33 um, which on average represented greater than 50% of particle population by volume. On average, these SPM concentration surrogates were three times higher in flood water than in ebb water; consistent with a loss of fine particles on the island. Following the highest flood tide, the decrease in fine particles was coincident with an increase in the concentration of particles larger than 130 um; a finding consistent with particle

  12. Heavy metal analysis of suspended particulate matter (SPM) and other samples from some workplaces in Kenya

    International Nuclear Information System (INIS)

    Kinyua, A.M.; Gatebe, C.K.; Mangala, M.J.

    1998-01-01

    Air pollution studies in Nairobi are indicating a rising trend in the particulate matter loading. The trend is mainly attributed to increased volume of motor vehicles, the physical change of the environment, agricultural and industrial activities. In this study, total suspended particulate matter sampling at the Nairobi industrial area and inside one workplace are reported. Included also are the results of analysis of water samples and effluents collected from a sugar factory, a tannery, and mercury (Hg) analysis in some beauty creams sold in Nairobi. The samples were analysed for heavy metal content using Energy Dispersive X-ray Fluorescence (EDXRF) while the suspended particulate matter (SPM) concentrations were determined by gravimetric technique. Total reflection x-ray fluorescence (TRXF), atomic absorption spectrophotometry and PIXE analytical techniques plus the use of Standard and Certified Reference Materials (SRM's and CRM's) were used for quality control, analysis and evaluation of the accrued data. Air sampling in the industrial area was done twice (Wednesday and Saturday) every week for a period of two months (November and December, 1996) and twice monthly for a period of six months (January-June 1997). Each sample covering approximately 24 hours, was collected using the 'Gent' Stacked Filter Unit (SFU), for day and night times. The SPM were found to vary from 16 to 83 mgm -3 during the sampling period. The analysis of dust collected inside a workplace showed that there was poor filtration of the air pumped into the building and that there was a need for improvement of the air conditioning unit plus reduction of emissions from a neighbouring tyre factory. Beauty creams analysed showed that there is some mercury present in significant amounts (0.14 - 3.0%). The results of these mercury levels are presented for various brands of cosmetics sold in some market outlets in Nairobi. The health implications on the presence of mercury in some of these beauty

  13. Monitoring of suspended particulate matter (SPM), heavy metals and other parameters in some workplaces

    International Nuclear Information System (INIS)

    Kinyua, A.M.; Gatebe, C.K.; Mangala, M.J.; Korir, A.K.; Bartilol, S.; Maina, D.M.; Mugera, W.G.; Kamau, G.N.; Chakaya, J.M.; Karama, M.; Miungu, D.M.; Kitio, V.

    2000-01-01

    This report presents results of measurements of sound levels, chemical analysis of air particulate matter and soil samples from two factories in Nairobi. A preliminary assessment of suspended particulate matter (SPM) in a residential site and its possible impacts on acute respiratory infections (ARI) of children under five years of age is also reported. Our investigations show that for Factory A, the Soil pH measurements within the Factory were more basic (pH=8.5) than those collected near a complainant's residence (pH=7.2). The sound level measurements showed that the maximum noise level recorded was 90 dB. This was at a distance of about 0.5 m from the main exhaust vent of the Factory (20 m above ground level). There was a strong ''detergent-perfume'' odour within and outside the Factory premises especially towards the complainant's side. However, the odour fluctuated. There was also no smoke emissions noticed during the site visits when the factory was operational. For Factory B, the major source of environmental degradation was drainage and management of the factory effluents. The BOD and COD levels for effluents samples analyzed ( 3 whereas the fine particles ranged from 16.2-24.4 μm/m 3 . The prevalence of ARI cases in 1998 ranged between 29.9% in January to the highest level of 59.6% in June. The total number of children who presented themselves throughout the study period, January-December 1998, was 146. A parallel study of dust sampling was also carried out from January to December 1998 in a typical office environment. Dust levels recorded from the working office environment at the Institute of Nuclear Science was found to range from 0. 44 -1.79 μg/cm 2 /day. (author)

  14. Modelling the transport of suspended particulate matter by the Rhone River plume (France). Implications for pollutant dispersion

    International Nuclear Information System (INIS)

    Perianez, R.

    2005-01-01

    A model to simulate the transport of suspended particulate matter by the Rhone River plume has been developed. The model solves the 3D hydrodynamic equations, including baroclinic terms and a 1-equation turbulence model, and the suspended matter equations including advection/diffusion of particles, settling and deposition. Four particle classes are considered simultaneously according to observations in the Rhone. Computed currents, salinity and particle distributions are, in general, in good agreement with observations or previous calculations. The model also provides sedimentation rates and the distribution of different particle classes over the sea bed. It has been found that high sedimentation rates close to the river mouth are due to coarse particles that sink rapidly. Computed sedimentation rates are also similar to those derived from observations. The model has been applied to simulate the transport of radionuclides by the plume, since suspended matter is the main vector for them. The radionuclide transport model, previously described and validated, includes exchanges of radionuclides between water, suspended matter and bottom sediment described in terms of kinetic rates. A new feature is the explicit inclusion of the dependence of kinetic rates upon salinity. The model has been applied to 137 Cs and 239,240 Pu. Results are, in general, in good agreement with observations. - A model has been developed to simulate transport of suspended particulate matter in the Rhone River plume

  15. Organochlorine pesticides in surface sediments and suspended particulate matters from the Yangtze estuary, China

    International Nuclear Information System (INIS)

    Liu Min; Cheng Shubo; Ou Dongni; Yang Yi; Liu Hualin; Hou Lijun; Gao Lei; Xu Shiyuan

    2008-01-01

    Total HCHs' and total DDTs' levels in surface sediments (SS) ranged from 0.5 to 17.5 ng g -1 and from 0.9 to 33.1 ng g -1 , averaged 6.0 and 8.2 ng g -1 , respectively. Total HCHs' and total DDTs' levels in suspended particulate matters (SPM) varied from 6.2 to 14.8 ng g -1 with a mean value of 12.3 ng g -1 and were from 3.4 to 25.7 ng g -1 with an average of 16.4 ng g -1 , respectively. Lindane is the main HCHs' source and continuing use in the Yangtze Delta areas of 'pure' γ-HCH (lindane) rather than technical HCH (a mix of largely α- and some γ-HCH). DDTs in SS are mainly accumulated in history. However, high DDT fractions in SPM are indicators of new input of typical dicofol type DDT from 2002 to 2004. It can be seen that most samples from the Yangtze estuary were in ranges where adverse biological effects are expected, either occasionally or frequently. - SPM, more polluted than SS, had similar contaminant composition. New input of lindane and typical dicofol type DDT were found and Yangtze estuary had been affected adversely

  16. Seasonal and tidal cycles of suspended particulates in the Irish Sea

    International Nuclear Information System (INIS)

    Weeks, Alison.

    1989-07-01

    The distribution of suspended particulate material (SPM) in the shelf seas and the processes controlling its variation are little known. This thesis reports an exploratory study of the spatial and time dependent variability of SPM in an area of the northern Irish Sea. SPM was determined both directly by gravimetric methods and via measurements of beam attenuation. Spatial distributions were determined from grid surveys using a profiling transmissometer. In addition a six month record of beam attenuation and current velocity was obtained from a site off the north coast of Anglesey. A strong seasonal cycle of beam attenuation was observed in mixed water, with values decreasing in June, July and August which suggested a reduction in the supply of SPM during summer. In stratified water, high concentrations of SPM remained confined to the dense layer below the thermocline. A regression model was found to explain 35% of the variance in data from a 5 week time series. 70% of the variance was explained for four day time series, near spring tides. The relationship between beam attenuation and tidal flows was more marked at spring tides than at neaps. (author)

  17. Organochlorine pesticides in surface sediments and suspended particulate matters from the Yangtze estuary, China

    Energy Technology Data Exchange (ETDEWEB)

    Liu Min [Department of Geography, Key Laboratory of Geographical Information Sciences of the State Ministry of Education, East China Normal University, Shanghai 200062 (China)], E-mail: mliu@geo.ecnu.edu.cn; Cheng Shubo; Ou Dongni [Department of Geography, Key Laboratory of Geographical Information Sciences of the State Ministry of Education, East China Normal University, Shanghai 200062 (China); Yang Yi [Vienna University, Department of Environmental Geoscience (Austria); Liu Hualin [Department of Geography, Key Laboratory of Geographical Information Sciences of the State Ministry of Education, East China Normal University, Shanghai 200062 (China); Hou Lijun [State Key Laboratory of Estuarine and Coastal Research, East China Normal University, Shanghai 200062 (China); Gao Lei; Xu Shiyuan [Department of Geography, Key Laboratory of Geographical Information Sciences of the State Ministry of Education, East China Normal University, Shanghai 200062 (China)

    2008-11-15

    Total HCHs' and total DDTs' levels in surface sediments (SS) ranged from 0.5 to 17.5 ng g{sup -1} and from 0.9 to 33.1 ng g{sup -1}, averaged 6.0 and 8.2 ng g{sup -1}, respectively. Total HCHs' and total DDTs' levels in suspended particulate matters (SPM) varied from 6.2 to 14.8 ng g{sup -1} with a mean value of 12.3 ng g{sup -1} and were from 3.4 to 25.7 ng g{sup -1} with an average of 16.4 ng g{sup -1}, respectively. Lindane is the main HCHs' source and continuing use in the Yangtze Delta areas of 'pure' {gamma}-HCH (lindane) rather than technical HCH (a mix of largely {alpha}- and some {gamma}-HCH). DDTs in SS are mainly accumulated in history. However, high DDT fractions in SPM are indicators of new input of typical dicofol type DDT from 2002 to 2004. It can be seen that most samples from the Yangtze estuary were in ranges where adverse biological effects are expected, either occasionally or frequently. - SPM, more polluted than SS, had similar contaminant composition. New input of lindane and typical dicofol type DDT were found and Yangtze estuary had been affected adversely.

  18. Characteristic of total suspended particulate (TSP) containing Pb and Zn at solid waste landfill

    Science.gov (United States)

    Budihardjo, M. A.; Noveandra, K.; Samadikun, B. P.

    2018-05-01

    Activities conducted at municipal solid waste landfills (MSWLs) potentially cause air pollution. Heavy vehicles in MSWLs release various pollutants that can have negative impacts for humans. One noticeable pollutant at MSWLs is airborne total suspended particulate (TSP) which may contain heavy metals such as Pb and Zn and can cause disease when inhaled by humans. In this study, TSP from a landfill in Semarang, Indonesia was collected and characterized to quantify the concentration of Pb and Zn. Meteorological factors (i.e. temperature, humidity and wind velocity) and landfill activities were considered as factors affecting pollutant concentrations. TSP was sampled using dust samplers while the concentrations of heavy metals in TSP were analyzed using an Atomic Absorption Spectrophotometer (AAS). Pb concentration ranged from 0.84 to 1.78 µg/m3 while Zn concentration was from 7.87 to 8.76 µg/m3. The levels of Pb were below the threshold specified by the Indonesian Government. Meanwhile, the threshold for Zn has not yet been determined.

  19. Association of uranium with colloidal and suspended particulate matter in Arabian sea near the west coast of Maharashtra (India)

    International Nuclear Information System (INIS)

    Singhal, R.K.; Joshi, S.N.; Hegde, A.G.

    2004-01-01

    Association of natural uranium in seawater with colloidal and suspended-particulate matter was determined. The separation of suspended particulate material (>0.45 ) and colloidal fraction (as dissolved fractions) in seawater were done by suction and ultra filtration techniques. Seawater samples were collected at 1 km away from the shore and subjected to sequential fractionation in nine stages ranging from 2.7 μm to 1.1 nm. Suspended particulate matter were separated in three different size groups namely >2.7 μm, 0.45 μm and 0.22 μm by suction filtration using cellulose acetate and nitrate membranes filters. To concentrate the solution with colloidal particles <0.22 μm-1.1 nm (0.5 k Nominal Molecular Weight cut-off Limit (NMWL), the solution obtained from filtration through <0.22 μm was passed through stirred ultra-filtration cell. The pH and conductivity at different stages of fractionation (dissolved) showed minor variations. The concentration of uranium was measured in suspended and dissolved fractions by using a pulsed nitrogen laser at 337.1 nm. In order to evaluate the role of mineral colloids in various stages of filtration, concentration of calcium, magnesium, potassium were measured by using ion chromatography and atomic absorption spectrometry. The clay mineral at seawater pH (approximately 8) behave as negative ions and provides binding site for the positively charge species of uranium. Among the dissolved fraction, the maximum concentrations of colloidal uranium was observed about 4 times higher than that compared to average concentration of 6.93 ± 3.10 ppb in other fractions. In the case of suspended particulate matter, the concentration of uranium was below detection limits (<1 ppb). The maximum concentration of Ca, Mg and K in the dissolved fraction were in the <1.1 nm fraction, while for suspended particulate matter, the concentration of Ca, Mg and K decreased with the decrease in size and it is highest in the fraction of 0.22 -0.45 μm.(author)

  20. How much suspended particulate matter enters long-term in-channel storage?

    Science.gov (United States)

    Dietrich, Stephan; Kleisinger, Carmen; Kehl, Nora; Schubert, Birgit; Hillebrand, Gudrun

    2017-04-01

    The route of suspended particulate matter (SPM) downstream rivers strongly depends on discharge conditions and involves transport times and periods with resting times in deposits e.g. at areas with low-flow conditions near the channel bed. It is, however, difficult to estimate the contribution of SPM on the bed load. In this study, particle-bound polychlorinated biphenyls (PCB), which were released by an incident in the Elbe river (Central Europe) in spring 2015, could be used as unique tracer for transport pathways of SPM along the whole river stretch (over 700 km length), including low mountain ranges, lowlands, and the estuary. In 2015 the Elbe River was characterized by low-discharge conditions. Thus, the export of SPM on flood plains was strongly limited. The incident was monitored by concentration measurements of seven indicator PCB congeners along the inland part of the Elbe River as well as in the Elbe estuary. Data from ten monitoring stations (settling tanks) are considered. The total PCB load is calculated for all stations on the basis of monthly contaminant concentrations and daily suspended sediment concentrations. Monte-Carlo simulations assess the uncertainties of the calculated load. It is shown that the ratio of high versus low chlorinated PCB congeners is a suitable tracer to distinguish the PCB load of the incident from the long-term background signal (hereafter PCB6 ratio). We demonstrate that both the load of PCB as well as its chemical fingerprint allows the estimation of transport durations for the transport processes involved. Only a little part of the suspension has been transported via wash load. The PCB6 ratio is used to estimate mean transport velocities of the wash load fraction. A direct transport of wash load via the mean flow velocity of the water was not observed. Shortly after the incident, the PCB6 ratio was monitored 257 km downstream of the incident site in April 2015, in May first occurrence was monitored 514 km downstream of

  1. [Distribution and origin of polycyclic aromatic hydrocarbons in suspended particulate matters from the Yangtze estuarine and nearby coastal areas].

    Science.gov (United States)

    Ou, Dong-ni; Liu, Min; Xu, Shi-yuan; Cheng, Shu-bo; Hou, Li-jun; Gao, Lei

    2008-09-01

    Parent PAHs have been quantified in suspended particulate matters from the Yangtze Estuarine and Coastal Areas. The results show that the concentrations of total PAHs ranged from 2278.79-14293.98 ng/g, and were characterized by greatest content near sewage discharge point with trend to decrease by increasing distance. As for PAHs composition, 4-6 rings PAHs were dominant while 2-3 rings PAHs were relative low. Cluster analysis found that except urban sewage discharge, the hydrodynamic force was influencing PAHs distribution patterns. Moreover, the content of suspended particulate matters, organic carbon and soot carbon of suspended particulate matters also play the important roles in PAHs distribution from the Yangtze estuarine and nearby coastal areas. Principal component analysis and PAH ratios demonstrated that uncompleted combustion of fossil fuels was the main source of PAHs in coastal areas, as well as a few anthropogenic releases of oil and oil products. Ecological risk assessment indicated that most of PAH compounds exceeded the effects range ER-L values and ISQV-L values, which might certain potential damage to the Yangtze Estuary ecosystem.

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

    Science.gov (United States)

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

    2017-09-01

    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

  3. Neutron activation analysis determination of trace elements in suspended particulate material and in central Thyrrenian sea sediments

    International Nuclear Information System (INIS)

    Madaro, M.; Moauro, R.; Boniforti, R.

    1985-01-01

    Neutron activation analysis and gamma-spectrometry have been applied to the instrumental determination of 26 elements (As, Au, Ca, Ce, Co, Cr, Cs, Eu, Fe, Hf, Hg, La, Lu, Mn, Rb, Sb, Sc, Se, Sm, Ta, Tb, Th, W, Yb, Zn, Zr) in samples of suspended particulate matter and sediments collected in the stretch of Tyrrhenian Sea between the Volturno River mouth and the Cape of Circeo. Some of these elements have particular importance because they can be toxic to the organisms or can be used as tracers in the aquatic environment of radioisotopes generated in activation or fission processes. Results show that some elements, not constituting particular crystal lattices, are more concentrated in particulate matter than in sediments. Such results agree with the hypothesis, supported also by others, that particulate matter acts as a scavenger with respect to most microelements, because of both biological and physico-chemical phenomena

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

    Directory of Open Access Journals (Sweden)

    M. El-Nouby Adam

    2013-01-01

    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.

  5. Holocene provenance shift of suspended particulate matter in the Amazon River basin

    Science.gov (United States)

    Höppner, Natalie; Lucassen, Friedrich; Chiessi, Cristiano M.; Sawakuchi, André O.; Kasemann, Simone A.

    2018-06-01

    The strontium (Sr), neodymium (Nd) and lead (Pb) isotope signatures of suspended particulate matter (SPM) in rivers reflect the radiogenic isotope signatures of the rivers' drainage basin. These signatures are not significantly affected by weathering, transport or depositional cycles, but document the sedimentary contributions of the respective sources. We report new Sr, Nd and Pb isotope ratios and element concentrations of modern SPM from the Brazilian Amazon River basin and document the past evolution of the basin by analyzing radiogenic isotopes of a marine sediment core from the slope off French Guiana archiving the last 40 kyr of Amazon River SPM, and the Holocene section of sediment cores raised between the Amazon River mouth and the slope off French Guiana. The composition of modern SPM confirms two main source areas, the Andes and the cratonic Shield. In the marine sediment core notable changes occurred during the second phase of Heinrich Stadial 1 (i.e. increased proportion of Shield rivers SPM) and during the last deglaciation (i.e. increased proportion of Madeira River SPM) together with elsewhere constant source contributions. Furthermore, we report a prominent offset in Sr and Nd isotopic composition between the average core value (εNd: -11.7 ± 0.9 (2SD), 87Sr/86Sr: 0.7229 ± 0.0016 (2SD)) and the average modern Amazon River SPM signal (εNd: -10.5 ± 0.5 (2SD), 87Sr/86Sr: 0.7213 ± 0.0036 (2SD)). We suggest that a permanent change in the Amazon River basin sediment supply during the late Holocene to a more Andean dominated SPM was responsible for the offset.

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

    Digital Repository Service at National Institute of Oceanography (India)

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

    of phytoplankton biomass. Ratio of silicate and nitrate to phosphate was 16:16:1 for monsoon and postmonsoon periods. Annual values of particulate carbohydrates, particulate proteins and particulate lipids in surface waters ranged from 40 to 265 mu g l sup(-1), 21...

  7. The genotoxic contribution of wood smoke to indoor respirable suspended particles

    Energy Technology Data Exchange (ETDEWEB)

    Boone, P.M. (John B. Pierce Foundation Laboratory, New Haven, CT (USA)); Rossman, T.G. (New York Univ. Medical Center, New York (USA)); Daisey, J.M. (Lawrence Berkeley Laboratory, CA (USA))

    1989-01-01

    The effect of wood burning stoves on the genotoxicity of indoor respirable organic matter was investigated for four homes during the winter and spring of 1986. Paired samples, one collected when the stove was not used and one when wood was burned, were extracted with dichloromethane and acetone. Aliquots of the dichloromethane extracts were analyzed with and without metabolic activation using the Microscreen bioassay. The Microscreen is a rapid, sensitive bioassay which measures a broad genotoxic endpoint, {lambda}-prophage induction. Per nanogram of organic material, wood smoke proved to be a major source of indirect (observed with metabolic activation) but not direct genotoxins in homes. The increase in indirect genotoxicity for extracts from aerosol containing wood smoke is probably due to higher concentrations of polycyclic aromatic hydrocarbons in the wood smoke aerosol as well as other unidentified classes. The direct genotoxicity observed for extracts of aerosol not containing wood smoke decreased with metabolic activation. This direct genotoxicity may be related to cooking activities in the homes. The trends in genotoxicity observed per nanogram of organic material are more pronounced when expressed per m{sup 3} of air due to the higher percentage of extractable material in aerosol containing wood smoke.

  8. Polarization-based enhancement of ocean color signal for estimating suspended particulate matter: radiative transfer simulations and laboratory measurements.

    Science.gov (United States)

    Liu, Jia; He, Xianqiang; Liu, Jiahang; Bai, Yan; Wang, Difeng; Chen, Tieqiao; Wang, Yihao; Zhu, Feng

    2017-04-17

    Absorption and scattering by molecules, aerosols and hydrosols, and the reflection and transmission over the sea surface can modify the original polarization state of sunlight. However, water-leaving radiance polarization, containing embedded water constituent information, has largely been neglected. Here, the efficiency of the parallel polarization radiance (PPR) for enhancing ocean color signal of suspended particulate matter is examined via vector radiative transfer simulations and laboratory experiments. The simulation results demonstrate that the PPR has a slightly higher ocean color signal at the top-of-atmosphere as compared with that of the total radiance. Moreover, both the simulations and laboratory measurements reveal that, compared with total radiance, PPR can effectively enhance the normalized ocean color signal for a large range of observation geometries, wavelengths, and suspended particle concentrations. Thus, PPR has great potential for improving the ocean color signal detection from satellite.

  9. Elemental analysis of the suspended particulate matter in the air of Tehran using INAA and AAS techniques. Appendix 11

    International Nuclear Information System (INIS)

    Sohrabpour, M.; Rostami, S.; Athari, M.

    1995-01-01

    A network of ten sampling stations for monitoring the elemental concentration of the suspended particulate matter (SPM) in the air of Tehran has been established. Instrumental neutron activation analysis (INAA) and atomic absorption spectrometry (AAS) techniques have been used for analysis of the Whatman-41 filters collected during the year 1994. Assessment of the preliminary results using the two techniques has produced the following twenty-one elements: Al, Br, Ca, Cd, Ce, Cl, Co, Cr, Cs, Fe, K, Mg, Mn, Na, Ni, Pb, Sb, Sc, Ti, V, Zn. Various standard solutions with known concentrations of elements, together with standard reference materials, have been used for quality assurance of the measured concentrations. (author)

  10. Polycyclic aromatic hydrocarbons in suspended particulate matter and sediments from the Pearl River Estuary and adjacent coastal areas, China

    International Nuclear Information System (INIS)

    Luo Xiaojun; Chen Shejun; Mai Bixian; Yang Qingshu; Sheng Guoying; Fu Jiamo

    2006-01-01

    The spatial distribution, composition, and sources of polycyclic aromatic hydrocarbons (PAHs) in sediments and suspended particulate matter (SPM) from the Pearl River Estuary and adjacent coastal areas were examined. Total PAH concentrations varied from 189 to 637 ng/g in sediments and 422 to 1850 ng/g in SPM. PAHs were dominated by 5,6-ring compounds in sediments and by 2,3-ring compounds in SPM samples. Assessment of PAH sources suggested that biomass and coal combustion is the major PAH source to the outer part of the estuary sediments and that petroleum combustion is the major PAH source to the inner part of estuary sediments. As for SPM samples, PAH isomer pair ratios indicated multiple (petroleum, petroleum combustion, and biomass and coal combustion) PAH sources, and significant temporal variations could exist for the sources of water column PAHs in the study area. The distribution of perylene in SPM samples indicated that the river was the dominant source of perylene in SPM and that perylene could be taken as an index to assess the contribution of river inflow to the total PAHs in SPM samples. The high concentration of perylene in the sediment was indicative of an in situ biogenic origin. - PAH were determined in suspended particulate matter and sediments from Pearl River Estuary

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

    Science.gov (United States)

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

    2014-01-01

    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. Comparison of remote sensing algorithms for retrieval of suspended particulate matter concentration from reflectance in coastal waters

    Science.gov (United States)

    Freeman, Lauren A.; Ackleson, Steven G.; Rhea, William Joseph

    2017-10-01

    Suspended particulate matter (SPM) is a key environmental indicator for rivers, estuaries, and coastal waters, which can be calculated from remote sensing reflectance obtained by an airborne or satellite imager. Here, algorithms from prior studies are applied to a dataset of in-situ at surface hyperspectral remote sensing reflectance, collected in three geographic regions representing different water types. These data show the optically inherent exponential nature of the relationship between reflectance and sediment concentration. However, linear models are also shown to provide a reasonable estimate of sediment concentration when utilized with care in similar conditions to those under which the algorithms were developed, particularly at lower SPM values (0 to 20 mg/L). Fifteen published SPM algorithms are tested, returning strong correlations of R2>0.7, and in most cases, R2>0.8. Very low SPM values show weaker correlation with algorithm calculated SPM that is not wavelength dependent. None of the tested algorithms performs well for high SPM values (>30 mg/L), with most algorithms underestimating SPM. A shift toward a smaller number of simple exponential or linear models relating satellite remote sensing reflectance to suspended sediment concentration with regional consideration will greatly aid larger spatiotemporal studies of suspended sediment trends.

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

    Science.gov (United States)

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

    2017-09-01

    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.

  14. The impact of total suspended particulate concentration on workers’ health at ceramic industry

    Science.gov (United States)

    Sintorini, M. M.

    2018-01-01

    Ceramic production process pollutes the air with particulate matter at high concentration and has negative impact on the workers. The objective of this research was to determine the particulate concentration in the air and to analyse its impact on the workers. This research used cross sectional method to correlate the particulate concentration, temperature, humidity, smoke level and level of workers’ compliance with safety regulations. Sampling was conducted from April to May 2012 in three locations, i.e. exposure area (Mass Preparation I, II) and non-exposure area (Forming area). In the exposure area (Mass Preparation I and II) where the particulate concentrations were 22.3673 mg/m3 and 14.8277 mg/m3, and 58.33%, the workers had bad health status. In the non-exposure area, where the particulate concentration was 3.2185 mg/m3 and 25% the workers had bad health status. The Odds Ratio among the workers in exposure area was 4.2 times higher than the workers in the non-exposure area.

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

    Digital Repository Service at National Institute of Oceanography (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. Regulation of suspended particulate matter (SPM) in Indian coal-based thermal power plants

    Science.gov (United States)

    Sengupta, Ishita

    Air borne particulate matter, in major Indian cities is at least three times the standard prescribed by the WHO. Coal-based thermal power plants are the major emitters of particulate matter in India. The lack of severe penalty for non-compliance with the standards has worsened the situation and thus calls for an immediate need for investment in technologies to regulate particulate emissions. My dissertation studies the optimal investment decisions in a dynamic framework, for a random sample of forty Indian coal-based power plants to abate particulate emissions. I used Linear Programming to solve the double cost minimization problem for the optimal choices of coal, boiler and pollution-control equipment. A policy analysis is done to choose over various tax policies, which would induce the firms to adopt the energy efficient as well as cost efficient technology. The aim here is to reach the WHO standards. Using the optimal switching point model I show that in a dynamic set up, switching the boiler immediately is always the cost effective option for all the power plants even if there is no policy restriction. The switch to a baghouse depends upon the policy in place. Theoretically, even though an emission tax is considered the most efficient tax, an ash tax or a coal tax can also be considered to be a good substitute especially in countries like India where monitoring costs are very high. As SPM is a local pollutant the analysis here is mainly firm specific.

  17. Optical properties of size fractions of suspended particulate matter in littoral waters of Québec

    Science.gov (United States)

    Mohammadpour, Gholamreza; Gagné, Jean-Pierre; Larouche, Pierre; Montes-Hugo, Martin A.

    2017-11-01

    Mass-specific absorption (ai∗(λ)) and scattering (bi∗(λ)) coefficients were derived for four size fractions (i = 0.2-0.4, 0.4-0.7, 0.7-10, and > 10 µm, λ = wavelength in nm) of suspended particulate matter (SPM) and with samples obtained from surface waters (i.e., 0-2 m depth) of the Saint Lawrence Estuary and Saguenay Fjord (SLE-SF) during June of 2013. For the visible-near-infrared spectral range (i.e., λ = 400-710 nm), mass-specific absorption coefficients of total SPM (i.e., particulates > 0.2 µm) (hereafter aSPM∗) had low values (e.g., 0.05 m2 g-1 at λ = 440 nm) corresponded with locations of the upper estuary and SF where particulates were mineral-rich and/or their mean diameter was relatively small. The variability of two optical proxies (the spectral slope of particulate beam attenuation coefficient and the mass-specific particulate absorption coefficient, hereafter γ and Svis, respectively) with respect to changes in particle size distribution (PSD) and chemical composition was also examined. The slope of the PSD was correlated with bi∗(550) (Spearman rank correlation coefficient ρs up to 0.37) and ai∗(440) estimates (ρs up to 0.32) in a comparable way. Conversely, the contribution of particulate inorganic matter to total mass of SPM (FSPMPIM) had a stronger correlation with ai∗ coefficients at a wavelength of 440 nm (ρs up to 0.50). The magnitude of γ was positively related to FSPMi or the contribution of size fraction i to the total mass of SPM (ρs up to 0.53 for i = 0.2-0.4 µm). Also, the relation between γ and FSPMPIM variability was secondary (ρs = -0.34, P > 0.05). Lastly, the magnitude of Svis was inversely correlated with aSPM∗(440) (ρs = -0.55, P = 0.04) and FSPMPIM (ρs = -0.62, P = 0.018) in sampling locations with a larger marine influence (i.e., lower estuary).

  18. Application of digital image processing to a β-gauge for determining mass concentration of suspending particulate matter in atmosphere

    International Nuclear Information System (INIS)

    Gotoh, Takao

    1992-01-01

    A two-dimensional image of the mass concentration of suspending particulate matter (SPM) collected on Millipore filter paper was photographed with Ultrofilm- 3 H. The printed paper image was transformed into a digital image (256 x 256 pixels) with 256 gray levels. Two results were obtained. The averaged values of gray level over all pixels of the digital image was found to correlate with the mass value measured by a β-gauge. The characteristic range of the digital image which was transformed to frequency by two-dimensional fast fourier transformation was found in the low frequency. It was presumed to relate to SPM from anthropogenic sources because the SPMs usually show higher density and smaller particle size than SPMs from natural sources. (author)

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

    International Nuclear Information System (INIS)

    Moreira, Silvana; Melo Junior, Ariston; Vives, Ana Elisa S. de; Nascimento Filho, Virgilio F.

    2005-01-01

    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 (μ-SRXRF) associated with the fundamental parameter method to correct attenuation/absorption effects by the matrix. The particles analyzed have size between 50-10 μm and to perform the spatial distribution a white beam of synchrotron radiation condensed by a conical capillary (13 μm 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)

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2005-07-01

    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)

  1. Multivariate analysis of the influences of oceanic and meteorological processes on suspended particulate matter distributions in Mississippi coastal waters

    Science.gov (United States)

    O'Brien, S. J.; Fitzpatrick, P. J.; Dzwonkowski, B.; Dykstra, S. L.; Wallace, D. J.; Church, I.; Wiggert, J. D.

    2016-02-01

    The Mississippi Sound is influenced by a high volume of sediment discharge from the Biloxi River, Mobile Bay via Pas aux Herons, Pascagoula River, Pearl River, Wolf River, and Lake Pontchartrain through the Rigolets. The river discharge, variable wind speed, wind direction and tides have a significant impact on the turbidity and transport of sediments in the Sound. Level 1 Moderate Resolution Imaging Spectroradiometer (MODIS) data is processed to extract the remote sensing reflectance at the wavelength of 645 nm and binned into an 8-day composite at a resolution of 500 m. The study uses a regional ocean color algorithm to compute suspended particulate matter (SPM) concentration based on these 8-day composite images. Multivariate analysis is applied between the SPM and time series of tides, wind, turbidity and river discharge measured at federal and academic institutions' stations and moorings. The multivariate analysis also includes in situ measurements of suspended sediment concentration and advective exchanges through the Mississippi Sound's tidal inlets between the coastal shelf and the nearshore estuarine waters. Mechanisms underlying the observed spatiotemporal distribution of SPM, including material exchange between the Sound and adjacent shelf waters, will be explored. The results of this study will contribute to current understanding of exchange mechanisms and pathways with the Mississippi Bight via the Mississippi Sound's tidal inlets.

  2. The dynamics of suspended particulate matter (SPM) and chlorophyll- a from intratidal to annual time scales in a coastal turbidity maximum

    NARCIS (Netherlands)

    van der Hout, C.M.; Witbaard, R.; Bergman, M.J.N.; Duineveld, G.C.A.; Rozemeijer, M.J.C.; Gerkema, T.

    2017-01-01

    The analysis of 1.8 years of data gives an understanding of the response to varying forcing of suspended particulate matter (SPM) and chlorophyll-a (CHL-a) in a coastal turbidity maximum zone (TMZ). Both temporal and vertical concentration variations in the near-bed layer (0–2 m) in the shallow (11

  3. The dynamics of suspended particulate matter (SPM) and chlorophyll-a from intratidal to annual time scales in a coastal turbidity maximum

    NARCIS (Netherlands)

    Hout, van der C.M.; Witbaard, R.; Bergman, M.J.N.; Duineveld, G.C.A.; Rozemeijer, M.J.C.; Gerkema, T.

    2017-01-01

    The analysis of 1.8. years of data gives an understanding of the response to varying forcing of suspended particulate matter (SPM) and chlorophyll-a (CHL-a) in a coastal turbidity maximum zone (TMZ). Both temporal and vertical concentration variations in the near-bed layer (0-2. m) in the shallow

  4. [Impact of atmospheric total suspended particulate pollution on photosynthetic parameters of street mango trees in Xiamen City].

    Science.gov (United States)

    Yu, Yu-xian; Chen, Jin-sheng; Ren, Yin; Li, Fang-yi; Cui, Sheng-hui

    2010-05-01

    With the development of urbanization, total suspended particulate (TSP) pollution is getting serious, and the normal physiological processes of urban vegetation are profoundly affected while adsorbing and purifying the particulates. In this study, four areas were selected, i.e., Tingxi reservoir (clean control area), Xiamen University (cultural and educational area), Xianyue (business area), and Haicang (industrial area), with their atmospheric TSP concentrations and the photosynthetic parameters of street Mango (Mangifera indica) trees monitored in April and May, 2009. The daily average concentration of TSP in Tingxi, Xiamen University, Xianyue, and Haicang was 0.061, 0.113, 0.120 and 0.205 mg x m(-3), respectively, and the impact of TSP stress on M. indica was in the sequence of Haicang > Xianyue > Xiamen University > Tingxi. TSP pollution negatively affected the net photosynthetic rate, stomatal conductance, and transpiration rate of M. indica, and induced intercellular CO2 concentration changed significantly. High TSP concentration could cause the decline of net photosynthetic rate via stomatal limitation.

  5. Investigating respirable particulates (PM10) around the world's largest mercury mine, Almaden, Spain

    Energy Technology Data Exchange (ETDEWEB)

    Gibbons, W.; Jones, T. [Cardiff Univ., Cardiff, Wales (United Kingdom). Dept. of Earth Sciences; Moreno, T.; Richards, R. [Cardiff Univ., Cardiff, Wales (United Kingdom). School of Biosciences; Higueras, P. [Almaden Univ. of Castilla-La Mancha, Almaden (Spain). Dept. of Geological Engineering

    2003-07-01

    The Almaden area in Spain has been mined for mercury since pre-Roman days. There is no evidence for significant contamination of the groundwater supply, since the lack of pyrite in the mercury deposits has prevented the formation of acid mine drainage. However, the main recognized environmental problem related to mercury mining has been the progressive poisoning of workers who are in direct contact with mercury vapours. This paper presents results of a study in which dust samples were collected from former mining and urban locations around Almaden. The samples were processed to extract their fine, respirable fraction. Mining activities have left contaminated ground, which under semi-arid conditions has created respirable mercury-bearing dusts. In some places the ground is severely contaminated with mercury as cinnabar and as schuetteite. Some of the contaminated areas are used for livestock grazing and growing plants for human consumption. A higher incidence of mercury-bearing particles is found in the finer fraction. The sizes of the mercury-bearing resuspended particles at all sites varies from inhalable dust, through respirable dust, to fine and ultrafine size capable of reaching the deepest levels of the lung alveoli. The most significant contamination is associated with old processing plants. Dust samples collected from Almaden, a town of 6,500 inhabitants, were found to contain significant amounts of respirable mercury-bearing aerosols.

  6. Spatial distribution of organic contaminants in three rivers of Southern England bound to suspended particulate material and dissolved in water.

    Science.gov (United States)

    Wilkinson, John L; Hooda, Peter S; Swinden, Julian; Barker, James; Barton, Stephen

    2017-09-01

    The spatial distribution of pharmaceuticals, personal care products (PPCPs) and other emerging contaminants (ECs) such as plasticisers, perflourinated compounds (PFCs) and illicit drug metabolites in water and bound to suspended particulate material (SPM) is not well-understood. Here, we quantify levels of thirteen selected contaminants in water (n=88) and their partition to suspended particulate material (SPM, n=16) in three previously-unstudied rivers of Greater London and Southern England during a key reproduction/spawning period. Analysis was conducted using an in-house validated method for Solid Phase Extraction followed by High-Performance Liquid Chromatography-Tandem Mass-Spectrometry. Analytes were extracted from SPM using an optimised method for ultrasonic-assisted solvent extraction. Detection frequencies of contaminants dissolved in water ranged from 3% (ethinylestradiol) to 100% (bisphenol-A). Overall mean concentrations in the aqueous-phase ranged from 14.7ng/L (benzoylecgonine) to 159ng/L (bisphenol-A). Sewage treatment works (STW) effluent was the predominant source of pharmaceuticals, while plasticisers/perfluorinated compounds may additionally enter rivers via other sources. In SPM, detection frequencies ranged from 44% (PFOA) to 94% (hydroxyacetophenone). Mean quantifiable levels of analytes bound to SPM ranged from 13.5ng/g dry SPM (0.33ng bound/L water) perfluorononanoic acid to 2830ng/g dry SPM (14.3ng bound/L water) perfluorooctanesulfonic acid. Long chain (>C7) amphipathic and acidic PFCs were found to more preferentially bind to SPM than short chain PFCs and other contaminants (Kd=34.1-75.5 vs contaminants entering rivers ranged from 0.157μg/person/day of benzoylecgonine (cocaine metabolite) to 58.6μg/person/day of bisphenol-A. The large sample size of this work (n=104) enabled ANOVA followed by Tukey HSD post-hoc tests to establish significant trends in PPCP/EC spatial distribution from headwaters through downstream stretches of studied

  7. Biogeochemical characteristics of suspended particulate matter in deep chlorophyll maximum layers in the southern East China Sea

    Directory of Open Access Journals (Sweden)

    Q. Liu

    2018-04-01

    Full Text Available Continental shelves and marginal seas are key sites of particulate organic matter (POM production, remineralization and sequestration, playing an important role in the global carbon cycle. Elemental and stable isotopic compositions of organic carbon and nitrogen are thus frequently used to characterize and distinguish POM and its sources in suspended particles and surface sediments in the marginal seas. Here we investigated suspended particulate matter (SPM collected around deep chlorophyll maximum (DCM layers in the southern East China Sea for particulate organic carbon and nitrogen (POC and PN contents and their isotopic compositions (δ13CPOC and δ15NPN to understand provenance and dynamics of POM. Hydrographic parameters (temperature, salinity and turbidity indicated that the study area was weakly influenced by freshwater derived from the Yangtze River during summer 2013. Elemental and isotopic results showed a large variation in δ13CPOC (−25.8 to −18.2 ‰ and δ15NPN (3.8 to 8.0 ‰, but a narrow molar C ∕ N ratio (4.1–6.3 and low POC ∕ Chl a ratio ( <  200 g g−1 in POM, and indicated that the POM in DCM layers was newly produced by phytoplankton. In addition to temperature effects, the range and distribution of δ13CPOC were controlled by variations in primary productivity and phytoplankton species composition; the former explained  ∼  70 % of the variability in δ13CPOC. However, the variation in δ15NPN was controlled by the nutrient status and δ15NNO3− in seawater, as indicated by similar spatial distribution between δ15NPN and the current pattern and water masses in the East China Sea; although interpretations of δ15NPN data should be verified with the nutrient data in future studies. Furthermore, the POM investigated was weakly influenced by the terrestrial OM supplied by the Yangtze River during summer 2013 due to the reduced sediment supply by the Yangtze River and north

  8. Biogeochemical characteristics of suspended particulate matter in deep chlorophyll maximum layers in the southern East China Sea

    Science.gov (United States)

    Liu, Qianqian; Kandasamy, Selvaraj; Lin, Baozhi; Wang, Huawei; Chen, Chen-Tung Arthur

    2018-04-01

    Continental shelves and marginal seas are key sites of particulate organic matter (POM) production, remineralization and sequestration, playing an important role in the global carbon cycle. Elemental and stable isotopic compositions of organic carbon and nitrogen are thus frequently used to characterize and distinguish POM and its sources in suspended particles and surface sediments in the marginal seas. Here we investigated suspended particulate matter (SPM) collected around deep chlorophyll maximum (DCM) layers in the southern East China Sea for particulate organic carbon and nitrogen (POC and PN) contents and their isotopic compositions (δ13CPOC and δ15NPN) to understand provenance and dynamics of POM. Hydrographic parameters (temperature, salinity and turbidity) indicated that the study area was weakly influenced by freshwater derived from the Yangtze River during summer 2013. Elemental and isotopic results showed a large variation in δ13CPOC (-25.8 to -18.2 ‰) and δ15NPN (3.8 to 8.0 ‰), but a narrow molar C / N ratio (4.1-6.3) and low POC / Chl a ratio ( < 200 g g-1) in POM, and indicated that the POM in DCM layers was newly produced by phytoplankton. In addition to temperature effects, the range and distribution of δ13CPOC were controlled by variations in primary productivity and phytoplankton species composition; the former explained ˜ 70 % of the variability in δ13CPOC. However, the variation in δ15NPN was controlled by the nutrient status and δ15NNO3- in seawater, as indicated by similar spatial distribution between δ15NPN and the current pattern and water masses in the East China Sea; although interpretations of δ15NPN data should be verified with the nutrient data in future studies. Furthermore, the POM investigated was weakly influenced by the terrestrial OM supplied by the Yangtze River during summer 2013 due to the reduced sediment supply by the Yangtze River and north-eastward transport of riverine particles to the northern East China

  9. Characterisation of the suspended particulate matter in a stratified estuarine environment employing complementary techniques

    Science.gov (United States)

    Thomas, Luis P.; Marino, Beatriz M.; Szupiany, Ricardo N.; Gallo, Marcos N.

    2017-09-01

    The ability to predict the sediment and nutrient circulation within estuarine waters is of significant economic and ecological importance. In these complex systems, flocculation is a dynamically active process that is directly affected by the prevalent environmental conditions. Consequently, the floc properties continuously change, which greatly complicates the characterisation of the suspended particle matter (SPM). In the present study, three different techniques are combined in a stratified estuary under quiet weather conditions and with a low river discharge to search for a solution to this problem. The challenge is to obtain the concentration, size and flux of suspended elements through selected cross-sections using the method based on the simultaneous backscatter records of 1200 and 600 kHz ADCPs, isokinetic sampling data and LISST-25X measurements. The two-ADCP method is highly effective for determining the SPM size distributions in a non-intrusive way. The isokinetic sampling and the LISST-25X diffractometer offer point measurements at specific depths, which are especially useful for calibrating the ADCP backscatter intensity as a function of the SPM concentration and size, and providing complementary information on the sites where acoustic records are not available. Limitations and potentials of the techniques applied are discussed.

  10. Application of a low energy x-ray spectrometer to analyses of suspended air particulate matter

    International Nuclear Information System (INIS)

    Giauque, R.D.; Garrett, R.B.; Goda, L.Y.; Jaklevic, J.M.; Malone, D.F.

    1975-01-01

    A semiconductor detector x-ray spectrometer has been constructed for the analysis of elements in air particulate specimens. The excitation radiation is provided, either directly or indirectly, using a low power (40 watts) Ag anode x-ray tube. Less than 100 ng for most of the elements in the range Mg → Zr, Pb are easily detected within two 1-minute counting intervals. A calibration technique for light element analysis and an experimental method which compensates for particle size effects are discussed. (auth)

  11. Optical properties of size fractions of suspended particulate matter in littoral waters of Québec

    Directory of Open Access Journals (Sweden)

    G. Mohammadpour

    2017-11-01

    Full Text Available Mass-specific absorption (ai∗(λ and scattering (bi∗(λ coefficients were derived for four size fractions (i =  0.2–0.4, 0.4–0.7, 0.7–10, and > 10 µm, λ = wavelength in nm of suspended particulate matter (SPM and with samples obtained from surface waters (i.e., 0–2 m depth of the Saint Lawrence Estuary and Saguenay Fjord (SLE-SF during June of 2013. For the visible–near-infrared spectral range (i.e., λ = 400–710 nm, mass-specific absorption coefficients of total SPM (i.e., particulates > 0.2 µm (hereafter aSPM∗ had low values (e.g., < 0.01 m2 g−1 at λ = 440 nm in areas of the lower estuary dominated by particle assemblages with relatively large mean grain size and high particulate organic carbon and chlorophyll a per unit of mass of SPM. Conversely, largest aSPM∗ values (i.e., > 0.05 m2 g−1 at λ = 440 nm corresponded with locations of the upper estuary and SF where particulates were mineral-rich and/or their mean diameter was relatively small. The variability of two optical proxies (the spectral slope of particulate beam attenuation coefficient and the mass-specific particulate absorption coefficient, hereafter γ and Svis, respectively with respect to changes in particle size distribution (PSD and chemical composition was also examined. The slope of the PSD was correlated with bi∗(550 (Spearman rank correlation coefficient ρs up to 0.37 and ai∗(440 estimates (ρs up to 0.32 in a comparable way. Conversely, the contribution of particulate inorganic matter to total mass of SPM (FSPMPIM had a stronger correlation with ai∗ coefficients at a wavelength of 440 nm (ρs up to 0.50. The magnitude of γ was positively related to FSPMi or the contribution of size fraction i to the total mass of SPM (ρs up to 0.53 for i = 0.2–0.4 µm. Also, the relation between γ and FSPMPIM variability was secondary (ρs = −0.34, P > 0.05. Lastly, the magnitude

  12. Inter-annual Variability in Global Suspended Particulate Inorganic Carbon Inventory Using Space-based Measurements

    Science.gov (United States)

    Hopkins, J.; Balch, W. M.; Henson, S.; Poulton, A. J.; Drapeau, D.; Bowler, B.; Lubelczyk, L.

    2016-02-01

    Coccolithophores, the single celled phytoplankton that produce an outer covering of calcium carbonate coccoliths, are considered to be the greatest contributors to the global oceanic particulate inorganic carbon (PIC) pool. The reflective coccoliths scatter light back out from the ocean surface, enabling PIC concentration to be quantitatively estimated from ocean color satellites. Here we use datasets of AQUA MODIS PIC concentration from 2003-2014 (using the recently-revised PIC algorithm), as well as statistics on coccolithophore vertical distribution derived from cruises throughout the world ocean, to estimate the average global (surface and integrated) PIC standing stock and its associated inter-annual variability. In addition, we divide the global ocean into Longhurst biogeochemical provinces, update the PIC biomass statistics and identify those regions that have the greatest inter-annual variability and thus may exert the greatest influence on global PIC standing stock and the alkalinity pump.

  13. Construction of Multi-Year Time-Series Profiles of Suspended Particulate Inorganic Matter Concentrations Using Machine Learning Approach

    Directory of Open Access Journals (Sweden)

    Pannimpullath R. Renosh

    2017-12-01

    Full Text Available Hydro-sedimentary numerical models have been widely employed to derive suspended particulate matter (SPM concentrations in coastal and estuarine waters. These hydro-sedimentary models are computationally and technically expensive in nature. Here we have used a computationally less-expensive, well-established methodology of self-organizing maps (SOMs along with a hidden Markov model (HMM to derive profiles of suspended particulate inorganic matter (SPIM. The concept of the proposed work is to benefit from all available data sets through the use of fusion methods and machine learning approaches that are able to process a growing amount of available data. This approach is applied to two different data sets entitled “Hidden” and “Observable”. The hidden data are composed of 15 months (27 September 2007 to 30 December 2008 of hourly SPIM profiles extracted from the Regional Ocean Modeling System (ROMS. The observable data include forcing parameter variables such as significant wave heights ( H s and H s 50 (50 days from the Wavewatch 3-HOMERE database and barotropic currents ( U b a r and V b a r from the Iberian–Biscay–Irish (IBI reanalysis data. These observable data integrate hourly surface samples from 1 February 2002 to 31 December 2012. The time-series profiles of the SPIM have been derived from four different stations in the English Channel by considering 15 months of output hidden data from the ROMS as a statistical representation of the ocean for ≈11 years. The derived SPIM profiles clearly show seasonal and tidal fluctuations in accordance with the parent numerical model output. The surface SPIM concentrations of the derived model have been validated with satellite remote sensing data. The time series of the modeled SPIM and satellite-derived SPIM show similar seasonal fluctuations. The ranges of concentrations for the four stations are also in good agreement with the corresponding satellite data. The high accuracy of the

  14. Nitrogen oxides, ozone and heavy metals analysis of suspended particulate matter (spm) of air in Nairobi, Kenya

    International Nuclear Information System (INIS)

    Odhiambo, O.; Kinyua, A.M.; Gatebe, C.K.

    2001-01-01

    Motor vehicle emissions are a major source of air pollution in most urban centers. In Kenya, Nairobi city has the highest traffic density and is therefore a particular cause for concern due to the poor maintenance standards of most vehicles plus the use of leaded gasoline. This study was carried out to determine the levels of nitrogen oxides (nox), suspended particulate matter (PM10), ozone (O3) and heavy metals in the SPM collected from the ambient air of Nairobi city. Sampling was done once every week for a period of three months (February to April 2000). Hourly average concentrations of N0 2 , NO and O3 were measured simultaneously from 9.00 am to 5.00 p.m., at a roundabout connecting two main highways (University and Uhuru) in the city. PM10 was collected using Gent Stacked Filter Unit (SFU) air sampler on nuclepore filters (0.4 and 8.0 ?m pore size for fine and coarse filters respectively) which were weighed and analysed for trace elements by Energy Dispersive X-ray Fluorescent (EDXRF) technique. Nitrogen oxides were analysed with thermo electron's Chemiluminescent nox Model 14B analyser while ozone was by using DASIBI ozone monitor, Model 1003 AH. An automatic vehicle counter was used For determining the vehicle density at the sampling point. The findings of the study show that the values obtained for Pb, Mn, Fe, Br, Zn, Cu and Ca are within the Who guidelines. Lead concentrations ranged from 0.051 to 1.106?g/m3; Fe, 0.149 to 3.154?g/m3; Mn, 0.002 to 0.526?g/m3; Cu, lower limit of detection (LLD) to 0.15?g/m3; Br, LLD to 0.43?g/m3; Zn, LLD to 0.14 ?g/m3 and Ca 2.18 to 5.389?g/m3. Concentrations of NO 2 , NO and O3 were also within the 8-hour Who limits with levels ranging from 0.011-0.976 ppm for NO, 0.001-0.2628 ppm for NO 2 and LLD-0.1258 ppm for ozone. The O3 levels were slightly higher in the afternoons when solar intensity was high especially the days with cloud cover of less than 3 Oktas. PM10 levels were, however, above the Who guidelines for most of

  15. Concentration, size, and density of total suspended particulates at the air exhaust of concentrated animal feeding operations.

    Science.gov (United States)

    Yang, Xufei; Lee, Jongmin; Zhang, Yuanhui; Wang, Xinlei; Yang, Liangcheng

    2015-08-01

    Total suspended particulate (TSP) samples were seasonally collected at the air exhaust of 15 commercial concentrated animal feeding operations (CAFOs; including swine finishing, swine farrowing, swine gestation, laying hen, and tom turkey) in the U.S. Midwest. The measured TSP concentrations ranged from 0.38 ± 0.04 mg m⁻³ (swine gestation in summer) to 10.9 ± 3.9 mg m⁻³ (tom turkey in winter) and were significantly affected by animal species, housing facility type, feeder type (dry or wet), and season. The average particle size of collected TSP samples in terms of mass median equivalent spherical diameter ranged from 14.8 ± 0.5 µm (swine finishing in winter) to 30.5 ± 2.0 µm (tom turkey in summer) and showed a significant seasonal effect. This finding affirmed that particulate matter (PM) released from CAFOs contains a significant portion of large particles. The measured particle size distribution (PSD) and the density of deposited particles (on average 1.65 ± 0.13 g cm⁻³) were used to estimate the mass fractions of PM10 and PM2.5 (PM ≤ 10 and ≤ 2.5 μm, respectively) in the collected TSP. The results showed that the PM10 fractions ranged from 12.7 ± 5.1% (tom turkey) to 21.1 ± 3.2% (swine finishing), whereas the PM2.5 fractions ranged from 3.4 ± 1.9% (tom turkey) to 5.7 ± 3.2% (swine finishing) and were smaller than 9.0% at all visited CAFOs. This study applied a filter-based method for PSD measurement and deposited particles as a surrogate to estimate the TSP's particle density. The limitations, along with the assumptions adopted during the calculation of PM mass fractions, must be recognized when comparing the findings to other studies.

  16. Size distribution and source identification of total suspended particulate matter and associated heavy metals in the urban atmosphere of Delhi.

    Science.gov (United States)

    Srivastava, Arun; Jain, V K

    2007-06-01

    A study of the atmospheric particulate size distribution of total suspended particulate matter (TSPM) and associated heavy metal concentrations has been carried out for the city of Delhi. Urban particles were collected using a five-stage impactor at six sites in three different seasons, viz. winter, summer and monsoon in the year 2001. Five samples from each site in each season were collected. Each sample (filter paper) was extracted with a mixture of nitric acid, hydrochloric acid and hydrofluoric acid. The acid solutions of the samples were analysed in five-particle fractions by atomic absorption spectrometry (AAS). The impactor stage fractionation of particles shows that a major portion of TSPM concentration is in the form of PM0.7 (i.e. metal mass viz. Mn, Cr, Cd, Pb, Ni, and Fe are also concentrated in the PM0.7 mode. The only exceptions are size distributions pertaining to Cu and Ca. Though, Cu is more in PM0.7 mode, its presence in size intervals 5.4-1.6microm and 1.6-0.7microm is also significant, whilst in case of Ca there is no definite pattern in its distribution with size of particles. The average PM10.9 (i.e. Source apportionment reveals that there are two sources of TSPM and PM10.9, while three and four sources were observed for PM1.6 (i.e. <1.6microm) and PM0.7, respectively. Results of regression analyses show definite correlations between PM10.9 and other fine size fractions, suggesting PM10.9 may adequately act as a surrogate for both PM1.6 and PM0.7, while PM1.6 may adequately act as a surrogate for PM0.7.

  17. Health impact of exposure to suspended particulate matter. Epidemiology of long-term effects

    International Nuclear Information System (INIS)

    Heinrich, Joachim; Peters, Annette; Wichmann, H.-Erich; Univ. Muenchen; Grote, Veit

    2002-01-01

    Chronic effects of ambient air pollutants are studied by cross-sectional and cohort designs including adjustment for confounder on an individual basis. This review summarizes the state of the art about chronic effects of ambient particulate air pollutants. A majority of regional cross-sectional studies show a higher risk for non-allergic, infectious respiratory diseases such as bronchitis in children who grew up in highly polluted areas. Impaired lung function was only shown in few of these studies, whereas in adults impairments were homogeneously seen in cross-sectional studies. A 10 μg/m 3 TSP or PM 10 increase in annual means increases the prevalence of bronchitis in children by 20-40%. According to North-American cohort studies total mortality can be estimated to increase by 24-50% for PM 10 (per 50 μg/m 3 increase), 17-25% for PM 2.5 (per 25 μg/m 3 increase), and 10-50% for sulfates (per 15 μg/m 3 increase). Prevalence of bronchitis and infectious respiratory health in East German children decreased along with the improvement of air quality. Further studies on chronic effects including an improved exposure assessment are needed to quantify health effects more precisely. These future studies should include a higher number of areas with different air pollution levels. They should help to set up more evidence-based regulations for the control of air pollutants and to improve the evaluation of clean air acts. (orig.) [de

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

    Science.gov (United States)

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

    2016-03-01

    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.

  19. Nutritional composition of suspended particulate matter in a tropical mangrove creek during a tidal cycle (Can Gio, Vietnam)

    Science.gov (United States)

    David, Frank; Marchand, Cyril; Taillardat, Pierre; Thành-Nho, Nguyễn; Meziane, Tarik

    2018-01-01

    Mangrove forests are highly productive ecosystems and mangrove-derived organic matter has generally been assumed to play a basal role in sustaining coastal food webs. However, the mechanisms of mangrove-derived organic matter utilisation by consumers are not fully understood. In this study, we were interested in hourly changes in the nutritional quality of suspended particulate matter (SPM) entering and departing a mangrove creek during a tidal cycle. We determined the fatty acid composition and δ13C stable isotope signature of SPM during a 26 h tidal cycle in a creek of the Can Gio Mangrove Biosphere Reserve (Southern Vietnam). Regarding fatty acids, the nutritional quality of SPM was low during most of the tidal cycle. However, it greatly increased during the first part of the strongest flood tide, occurring during daytime. The pulse of highly nutritive organic matter brought to the ecosystem was mostly composed of algal cells growing in specific shallow zones of the mangrove, that use nutrients and CO2 exported during the preceding ebb tide and originating from the mineralisation of mangrove-derived organic matter, as evidenced by their δ13C signatures. This study confirms that mangrove-derived carbon plays a basal role in sustaining trophic webs of mangrove tidal creeks, but that its nutritive value is greatly enhanced when a first step of mineralisation is achieved and CO2 is photosynthesised by algal cells.

  20. Suspended particulate matter estimates using optical and acoustic sensors: application in Nestos River plume (Thracian Sea, North Aegean Sea).

    Science.gov (United States)

    Anastasiou, Sotiria; Sylaios, Georgios K; Tsihrintzis, Vassilios A

    2015-06-01

    The present study investigates the use of combined methods of optical and acoustic sensors, in collaboration with direct in situ measurements, for the calibration and validation of a model transforming acoustic backscatter intensity series into suspended particulate matter (SPM) concentration datasets. The model follows previously elaborated techniques, placing particular attention to the parameterization of the acoustic absorption index as a function of water physical properties. Results were obtained from the annual deployment (during 2007-2008) of an upward-facing acoustic Doppler current profiler (ADCP) (307 kHz), equipped with a Wave Array, and an optical backscatter sensor (OBS), at the bottom of Thassos Passage near Nestos River plume (Thracian Sea, Northern Greece). The OBS was calibrated through linear regression, using 2007 and 2012 field sampling data, exhibiting an error of 13-14 % due to chlorophyll presence. The ADCP signal was calibrated through simultaneous measurements of backscatter intensity and turbidity profiles. Harmonic analysis on the model-produced SPM concentrations explained the tidal influence on their variability, especially during the summer. Empirical orthogonal functions analysis revealed the impact of waves and wave-induced currents on SPM variability. Finally, Nestos River sediment load was found uncorrelated to the SPM change in Thassos Passage, due to the dispersal and sediment deposition near the river mouth.

  1. Monitoring the effects of disposal of fine sediments from maintenance dredging on suspended particulate matter concentration in the Belgian nearshore area

    OpenAIRE

    Fettweis, M.; Baeye, M.; Francken, F.; Lauwaert, B.; Van den Eynde, D.; Van Lancker, V.; Martens, C.; Michielsen, T.

    2012-01-01

    The impact of continuous disposal of fine-grained sediments from maintenance dredging works on the suspended particulate matter concentration in a shallow nearshore turbidity maximum was investigated during dredging experiment (port of Zeebrugge, southern North Sea). Before, during and after the experiment monitoring of SPM concentration using OBS and ADV altimetry was carried out at a location 5 km west of the disposal site. A statistical analysis, based on the concept of populations and sub...

  2. Monitoring the effects of disposal of fine sediments from maintenance dredging on suspended particulate matter concentration in the Belgian nearshore area (southern North Sea)

    OpenAIRE

    Fettweis, M.; Baeye, M.; Francken, F.; Lauwaert, B.; Van den Eynde, D.; Van Lancker, V.; Martens, C.; Michielsen, T.

    2011-01-01

    The impact of continuous disposal of fine-grained sediments from maintenance dredging works on the suspended particulate matter concentration in a shallow nearshore turbidity maximum was investigated during dredging experiment (port of Zeebrugge, southern North Sea). Before, during and after the experiment monitoring of SPM concentration using OBS and ADV altimetry was carried out at a location 5 km west of the disposal site. A statistical analysis, based on the concept of populations and sub...

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

    Science.gov (United States)

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

    2015-12-01

    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

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

    Directory of Open Access Journals (Sweden)

    M. Baborowski

    2004-01-01

    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

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

    2008-04-10

    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

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

    Science.gov (United States)

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

    2012-12-01

    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

  7. Characterisation of urban catchment suspended particulate matter (Auckland region, New Zealand); a comparison with non-urban SPM

    International Nuclear Information System (INIS)

    Bibby, Rebecca L.; Webster-Brown, Jenny G.

    2005-01-01

    Suspended particulate matter (SPM) is an important transport agent for metal contaminants in streams, particularly during high flow periods such as storm events. For highly contaminated urban catchments in the greater Auckland (New Zealand) area, trace metal partitioning between the dissolved phase and SPM was determined, and SPM characterised in terms of its Si, Al, Fe, Mn, Zn, Cu, Pb, TOC, TON and PO 4 concentrations, as well as particle size, abundance, type and surface area. This data was compared to similar data from representative non-urban catchments in the Auckland region, the Kaipara River and Waikato River catchments, to identify any significant differences in the SPM and its potential trace metal adsorption capacity. Trace metal partitioning was assessed by way of a distribution coefficient: K D =[Me SPM ]/[Me DISS ]. Auckland urban SPM comprises quartz, feldspars and clay minerals, with Fe-oxides and minor Mn-oxides. No particles of anthropogenic origin, other than glass shards, were observed. No change in urban SPM particle size or SSA was observed with seasonal change in temperature, but the nature of the SPM was observed to change with flow regime. The abundance of finer particles, SSA and Al content of the SPM increased under moderate flow conditions; however, Si/Al ratios remained constant, confirming the importance of aluminosilicate detrital minerals in surface run-off. The SPM Fe content was observed to decrease with increased flow and was attributed to dilution of SPM Fe-oxide of groundwater origin. The Kaipara River SPM was found to be mineralogically, chemically and biologically similar to the urban SPM. However, major differences between urban catchment SPM and SPM from the much larger (non-urban) Waikato River were observed, and attributed to a higher abundance of diatoms. The Fe content of the Waikato River SPM was consistently lower (<5%), and the Si/Al ratio and Mn content was higher. Such differences observed between urban and non

  8. Winter-time size distribution and source apportionment of total suspended particulate matter and associated metals in Delhi

    Science.gov (United States)

    Srivastava, Arun; Gupta, Sandeep; Jain, V. K.

    2009-03-01

    A study of the winter time size distribution and source apportionment of total suspended particulate matter (TSPM) and associated heavy metal concentrations have been carried out for the city of Delhi. This study is important from the point of view of implementation of compressed natural gas (CNG) as alternate of diesel fuel in the public transport system in 2001 to reduce the pollution level. TSPM were collected using a five-stage cascade impactor at six sites in the winters of 2005-06. The results of size distribution indicate that a major portion (~ 40%) of TSPM concentration is in the form of PM0.7 (heavy metals associated with various size fractions of TSPM. A very good correlation between coarse and fine size fraction of TSPM was observed. It was also observed that the metals associated with coarse particles have more chances of correlation with other metals; rather they are associated with fine particles. Source apportionment was carried out separately in coarse and fine size modes of TSPM by Chemical Mass Balance Receptor Model (CMB8) as well as by Principle Component Analysis (PCA) of SPSS. Source apportionment by PCA reveals that there are two major sources (possibly vehicular and crustal re-suspension) in both coarse and fine size fractions. Results obtained by CMB8 show the dominance of vehicular pollutants and crustal dust in fine and coarse size mode respectively. Noticeably the dominance of vehicular pollutants are now confined to fine size only whilst during pre CNG era it dominated both coarse and fine size mode. An increase of 42.5, 44.4, 48.2, 38.6 and 38.9% in the concentrations of TSPM, PM10.9, coarse particles, fine particles and lead respectively was observed during pre (2001) to post CNG (2005-06) period.

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

    Directory of Open Access Journals (Sweden)

    Ahuja Tarushee

    2011-04-01

    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.

  10. Heavy metal partitioning of suspended particulate matter-water and sediment-water in the Yangtze Estuary.

    Science.gov (United States)

    Feng, Chenghong; Guo, Xiaoyu; Yin, Su; Tian, Chenhao; Li, Yangyang; Shen, Zhenyao

    2017-10-01

    The partitioning of ten heavy metals (As, Cd, Co, Cr, Cu, Hg, Ni, Pb, Sb, and Zn) between the water, suspended particulate matter (SPM), and sediments in seven channel sections during three hydrologic seasons in the Yangtze Estuary was comprehensively investigated. Special attention was paid to the role of tides, influential factors (concentrations of SPM and dissolved organic carbon, and particle size), and heavy metal speciation. The SPM-water and sediment-water partition coefficients (K p ) of the heavy metals exhibited similar changes along the channel sections, though the former were larger throughout the estuary. Because of the higher salinity, the K p values of most of the metals were higher in the north branch than in the south branch. The K p values of Cd, Co, and As generally decreased from the wet season to the dry season. Both the diagonal line method and paired samples t-test showed that no specific phase transfer of heavy metals existed during the flood and ebb tides, but the sediment-water K p was more concentrated for the diagonal line method, owing to the relatively smaller tidal influences on the sediment. The partition coefficients (especially the K p for SPM-water) had negative correlations with the dissolved organic carbon (DOC) but positive correlations were noted with the particle size for most of the heavy metals in sediment. Two types of significant correlations were observed between K p and metal speciation (i.e., exchangeable, carbonate, reducible, organic, and residual fractions), which can be used to identify the dominant phase-partition mechanisms (e.g., adsorption or desorption) of heavy metals. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. CD28 in thymocyte development and peripheral T cell activation in mice exposed to suspended particulate matter

    International Nuclear Information System (INIS)

    Drela, Nadzieja; Zesko, Izabela; Jakubowska, Martyna; Biernacka, Marzena

    2006-01-01

    The CD28:B7 signaling pathway is very important for the activity of mature peripheral T lymphocytes and thymocyte development. The proper development of thymocytes into mature single positive CD4 + and CD8 + T cells is crucial for almost all immune functions. In naturally occurring conditions, T cells maturation in the thymus is influenced by environmental agents. The expression of CD28 and the distribution of CD28 low/high thymocytes have been examined at various stages of thymocyte development in BALB/c mice exposed to air-suspended particulate matter (ASM). Acute exposure to ASM resulted in the decrease of CD28 expression in the total thymocyte population. The increase of the percentage of CD28 low and the decrease of CD28 high thymocytes were observed, which may account for the acceleration of thymocyte development under the conditions of elevated risk resulting from the exposure of animals to environmental xenobiotics. ASM exposure resulted in the increase of the level of proliferation of lymph node T cells induced by anti-CD3 and anti-CD28 monoclonal antibodies activation despite normal expression of CD28 molecule. In contrast, the level of proliferation of spleen T cells was lowered or normal dependently of the concentration of stimuli used for activation. Results of these studies demonstrate that acute exposure of mice to ASM can result in the progression of two contrasting processes in the immune system: upregulation of thymocyte development, which contributes to the maintenance of peripheral T cell pool, and over-activation of lymph node lymphocytes, which may lead to uncontrolled immunostimulation

  12. 78 FR 54432 - Development of Inward Leakage Standards for Half-Mask Air-Purifying Particulate Respirators

    Science.gov (United States)

    2013-09-04

    ... Respirators. Procedure No. RCT-APR-STP-0068. Available at http://www.cdc.gov/niosh/docket/archive/pdfs/NIOSH... currently market quarter-mask respirators? If you are a purchaser, do you currently use quarter-mask...

  13. Nanoparticle filtration performance of NIOSH-certified particulate air-purifying filtering facepiece respirators: evaluation by light scattering photometric and particle number-based test methods.

    Science.gov (United States)

    Rengasamy, Samy; Eimer, Benjamin C

    2012-01-01

    National Institute for Occupational Safety and Health (NIOSH) certification test methods employ charge neutralized NaCl or dioctyl phthalate (DOP) aerosols to measure filter penetration levels of air-purifying particulate respirators photometrically using a TSI 8130 automated filter tester at 85 L/min. A previous study in our laboratory found that widely different filter penetration levels were measured for nanoparticles depending on whether a particle number (count)-based detector or a photometric detector was used. The purpose of this study was to better understand the influence of key test parameters, including filter media type, challenge aerosol size range, and detector system. Initial penetration levels for 17 models of NIOSH-approved N-, R-, and P-series filtering facepiece respirators were measured using the TSI 8130 photometric method and compared with the particle number-based penetration (obtained using two ultrafine condensation particle counters) for the same challenge aerosols generated by the TSI 8130. In general, the penetration obtained by the photometric method was less than the penetration obtained with the number-based method. Filter penetration was also measured for ambient room aerosols. Penetration measured by the TSI 8130 photometric method was lower than the number-based ambient aerosol penetration values. Number-based monodisperse NaCl aerosol penetration measurements showed that the most penetrating particle size was in the 50 nm range for all respirator models tested, with the exception of one model at ~200 nm size. Respirator models containing electrostatic filter media also showed lower penetration values with the TSI 8130 photometric method than the number-based penetration obtained for the most penetrating monodisperse particles. Results suggest that to provide a more challenging respirator filter test method than what is currently used for respirators containing electrostatic media, the test method should utilize a sufficient number

  14. Quantifying uncertainty in measurement of mercury in suspended particulate matter by cold vapor technique using atomic absorption spectrometry with hydride generator.

    Science.gov (United States)

    Singh, Nahar; Ahuja, Tarushee; Ojha, Vijay Narain; Soni, Daya; Tripathy, S Swarupa; Leito, Ivo

    2013-01-01

    As a result of rapid industrialization several chemical forms of organic and inorganic mercury are constantly introduced to the environment and affect humans and animals directly. All forms of mercury have toxic effects; therefore accurate measurement of mercury is of prime importance especially in suspended particulate matter (SPM) collected through high volume sampler (HVS). In the quantification of mercury in SPM samples several steps are involved from sampling to final result. The quality, reliability and confidence level of the analyzed data depends upon the measurement uncertainty of the whole process. Evaluation of measurement uncertainty of results is one of the requirements of the standard ISO/IEC 17025:2005 (European Standard EN IS/ISO/IEC 17025:2005, issue1:1-28, 2006). In the presented study the uncertainty estimation in mercury determination in suspended particulate matter (SPM) has been carried out using cold vapor Atomic Absorption Spectrometer-Hydride Generator (AAS-HG) technique followed by wet chemical digestion process. For the calculation of uncertainty, we have considered many general potential sources of uncertainty. After the analysis of data of seven diverse sites of Delhi, it has been concluded that the mercury concentration varies from 1.59 ± 0.37 to 14.5 ± 2.9 ng/m(3) with 95% confidence level (k = 2).

  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

    Energy Technology Data Exchange (ETDEWEB)

    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)

    2011-05-15

    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. 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.

    Science.gov (United States)

    Gaidajis, George

    2003-01-01

    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.

  17. Magnesium-rich minerals in sediment and suspended particulates of South Florida water bodies: implications for turbidity.

    Science.gov (United States)

    Harris, W G; Fisher, M M; Cao, X; Osborne, T; Ellis, L

    2007-01-01

    Fine sediments in shallow water bodies such as Lake Okeechobee are prone to resuspension. Predominantly inorganic "mud" sediment that covers approximately 670 km2 of the lake has been recognized as a persistent source of turbidity. The objective of this study was to determine if mineral components of sediments in Lake Okeechobee and water conveyances of the northern Everglades also occur as suspended sediment and hence constitute a potential abiotic contributor to turbidity. Sediment samples were collected from nine stations within the lake and eight locations north of Water Conservation Area 2A in the Everglades. Water samples were also collected at selected locations. The silt and clay mineralogy of sediment and suspended particles was determined using X-ray diffraction, thermogravimetry, scanning-electron microscopy, energy-dispersive X-ray elemental microanalysis, and high-resolution transmission-electron microscopy. Clay fractions of the lake sediment contained the Mg silicate minerals sepiolite and palygorskite, along with smectite, dolomite, calcite, and kaolinite. Sediment silt fractions were dominated by carbonates and/or quartz, with smaller amounts of Ca phosphates and sepiolite. Mineralogy of the mud sediment was similar to that reported for geologic phosphate deposits. This suggests that the mud sediment might have accumulated by stream transport of minerals from these deposits. Suspended solids and mud-sediment mineralogy were similar, except that smectite was more abundant in suspended solids. Everglade samples also contained Mg-rich minerals. The small size, low density, and fibrous or platy nature of the prevalent mud sediment minerals make them an abiotic, hydrodynamically sensitive source of persistent turbidity in a shallow lake. Mitigation efforts focused exclusively on P-induced biogeochemical processes do not address the origin or effects of these minerals. Ecological management issues such as turbidity control, P retention, geologic P input

  18. Basic microscopic theory of the distribution, transfer and uptake kinetics of dissolved radionuclides by suspended particulate matter - Part I; Theory development

    International Nuclear Information System (INIS)

    Abril, J.M.

    1998-01-01

    Recently much experimental effort has been focused on determining those factors which affect the kinetics and the final equilibrium conditions for the uptake of radionuclides from the aqueous phase by particulate matter. At present, some of these results appear to be either surprising or contradictory and introduce some uncertainty in which parameter values are most appropriate for environmental modelling. In this paper, we study the ionic exchange between the dissolved phase and suspended particles from a microscopic viewpoint, developing a mathematical description of the kinetic transfer and the k d distribution coefficients. The most relevant contribution is the assumption that the exchange of radionuclides occurs in a specific surface layer on the particles, with a non-zero thickness. A wide range of experimental findings can be explained with this theory. (Copyright (c) 1998 Elsevier Science B.V., Amsterdam. All rights reserved.)

  19. 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

    Digital Repository Service at National Institute of Oceanography (India)

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

    zooplankton, and then known aliquots (0.25 to 1.5 L) were filtered through pre-combusted (450 °C, 4h) 47 mm GF/F filter papers (0.7 µm, Whatman) for the measurements of suspended particulate matter (SPM), particulate organic carbon (POC), δ13CPOC, δ15NTPN... analysis. 2.3. Determination of bulk parameters and stable isotopes GF/F (0.7 µm, 47 mm) filter containing particulate matter was washed with UV-Milli-Q- water to remove salt and the filter was dried at 40 °C for 24 h. Filter was cooled and weighed...

  20. Principal sources and dispersal patterns of suspended particulate matter in nearshore surface waters of the northeast Pacific Ocean and the Hawaiian Islands

    Science.gov (United States)

    Carlson, P. R. (Principal Investigator); Conomos, T. J.; Janda, R. J.; Peterson, D. H.

    1973-01-01

    The author has identified the following significant results. ERTS-1 multispectral scanner imagery of the nearshore surface waters of the Northeast Pacific Ocean is proving to be a useful tool for determining source and dispersal of suspended particulate matter. The principal sources of the turbid water, seen best on the green and red bands, are river and stream effluents and actively eroding coastlines; secondary sources are waste effluents and production of planktonic organisms, but these may sometimes be masked by the very turbid plumes of suspended sediment being discharged into the nearshore zone during times of high river discharge. The configuration and distribution of the plumes of turbid water also can be used to infer near-surface current directions. Comparison of imagery of the nearshore water off the northern California coast from October 1972 and January 1973 shows a reversal of the near-surface currents, from predominantly south-setting in the fall (California Current) to north-setting in the winter (Davidson Current).

  1. Suspended particulate matter in New York City: element concentrations as a function of particle size and elevation above street

    International Nuclear Information System (INIS)

    Bauman, S.E.; Williams, E.T.; Finston, H.L.; Bond, A.H. Jr.; Lesser, P.M.S.; Ferrand, E.F.

    1977-01-01

    Aerosol samples were simultaneously collected at two street-level locations and the 16th floor, on two sides of a Manhattan city block. The results of PIXE analysis, together with CO and SO 2 data, show that the concentrations of substances emitted at street level (CO, Pb, etc) are significantly less at the 16th floor whereas particulate sulfur shows little variation. Other conclusions are presented

  2. 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.

    Science.gov (United States)

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

    2017-07-01

    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 Zn JMC  = +0.49 ± 0.06‰, 2σ, n = 3) compared to sampling locations outside (δ 66 Zn JMC  = +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.

  3. Sampling of suspended particulate matter using particle traps in the Rhône River: Relevance and representativeness for the monitoring of contaminants.

    Science.gov (United States)

    Masson, M; Angot, H; Le Bescond, C; Launay, M; Dabrin, A; Miège, C; Le Coz, J; Coquery, M

    2018-05-10

    Monitoring hydrophobic contaminants in surface freshwaters requires measuring contaminant concentrations in the particulate fraction (sediment or suspended particulate matter, SPM) of the water column. Particle traps (PTs) have been recently developed to sample SPM as cost-efficient, easy to operate and time-integrative tools. But the representativeness of SPM collected with PTs is not fully understood, notably in terms of grain size distribution and particulate organic carbon (POC) content, which could both skew particulate contaminant concentrations. The aim of this study was to evaluate the representativeness of SPM characteristics (i.e. grain size distribution and POC content) and associated contaminants (i.e. polychlorinated biphenyls, PCBs; mercury, Hg) in samples collected in a large river using PTs for differing hydrological conditions. Samples collected using PTs (n = 74) were compared with samples collected during the same time period by continuous flow centrifugation (CFC). The grain size distribution of PT samples shifted with increasing water discharge: the proportion of very fine silts (2-6 μm) decreased while that of coarse silts (27-74 μm) increased. Regardless of water discharge, POC contents were different likely due to integration by PT of high POC-content phytoplankton blooms or low POC-content flood events. Differences in PCBs and Hg concentrations were usually within the range of analytical uncertainties and could not be related to grain size or POC content shifts. Occasional Hg-enriched inputs may have led to higher Hg concentrations in a few PT samples (n = 4) which highlights the time-integrative capacity of the PTs. The differences of annual Hg and PCB fluxes calculated either from PT samples or CFC samples were generally below 20%. Despite some inherent limitations (e.g. grain size distribution bias), our findings suggest that PT sampling is a valuable technique to assess reliable spatial and temporal trends of particulate

  4. Validation of a field filtration technique for characterization of suspended particulate matter from freshwater. Part II. Minor, trace and ultra trace elements

    International Nuclear Information System (INIS)

    Odman, Fredrik; Ruth, Thomas; Rodushkin, Ilia; Ponter, Christer

    2006-01-01

    A field filtration method for the concentration and separation of suspended particulate matter (SPM) from freshwater systems and the subsequent determination of minor, trace and ultra trace elements (As, Ba, Be, Cd, Co, Cr, Cs, Cu, Ga, Hf, Mo, Nb, Ni, Pb, Rb, Sb, Sc, Sn, Sr, Ta, Th, Tl, U, V, W, Zn and Zr) is validated with respect to detection limits, precision and bias. The validation comprises the whole procedure including filtration, sample digestion and instrumental analysis. The method includes two digestion procedures (microwave acid digestion and alkali fusion) in combination with inductively coupled plasma atomic emission spectrometry (ICP-AES) and inductively coupled plasma quadrupole mass spectrometry (ICP-QMS). Total concentrations of these 27 trace and minor elements have been determined in suspended particulate matter (SPM) from lake and river water with low levels of suspended solids ( -1 DW), and a wide range of element concentrations. The precision of the method including filtration, digestion and instrumental determination ranges between 8% and 18% RSD for most elements on a dry weight basis. Higher recovery after acid digestion is found for some elements, probably because of volatilization or retention losses in the fusion procedure. Other elements show higher recovery after fusion, which is explained by more efficient decomposition of refractory mineral phases relative to the non-total acid digestion. Non-detectable concentrations of some elements are reported due to small differences between blank filter levels and the amounts of elements present on the filters after sampling. The method limits of detection range between 0.7 ng and 2.65 μg, as estimated from the blank filter samples. These detection limits are 10-550 times higher compared to the corresponding instrumental limits of detection. The accuracy and bias of the overall analytical procedure was assessed from replicate analysis of certified reference materials. A critical evaluation of

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

    Digital Repository Service at National Institute of Oceanography (India)

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

    and pseudopeptidoglycan (Brock et al 1994). AS are also important con- stituents of many biopolymers such as polysac- charides, glycoproteins and glycolipids (Sharon 1965). Moreover, chitin, a polymer of amino sugar, N-acetyl glucosamine (Muzzarelli 1977; Benner.../F glass fibre filters (0.7?m pore size) for the analysis of particu- late organic carbon (POC), particulate nitrogen (PN) and amino sugars (AS) concentration and composition. 2.3 Analysis of samples The SPM samples were de-carbonated overnight using fuming...

  6. Carbon isotopic ratio of suspended organic matter of the Gironde estuary. Application to particulate Zn and Pb distribution

    International Nuclear Information System (INIS)

    Fontugne, Michel; Jouanneau, J.M.

    1981-01-01

    In the Gironde estuary, the isotopic ratio of particulate organic carbon (P.O.C.), and the ratio metal/P.O.C. indicate the occurrence of two zones. Up-river, the concentration decreases due to the consumption of the organo-metallic phase and by mixing in the ''mud plug'' with terrestrial particles impoverished in metal and P.O.C. Down-stream, the mixing of metal rich terrestrial P.O.C. with poorer marine particles determines the metal concentrations [fr

  7. Influence of environmental factors on absorption characteristics of suspended particulate matter and CDOM in Liaohe River watershed, northeast China.

    Science.gov (United States)

    Shao, Tiantian; Zheng, Hui; Song, Kaishan; Zhao, Ying; Zhang, Bai

    2017-08-01

    Absorption characteristics of optically active substances, including non-algal particles, phytoplankton, and chromophoric dissolved organic matter (CDOM), were measured in conjunction with environmental factors in five rivers within the Liaohe River watershed. Spectral absorption of non-algal particles [a NAP (λ)] was similar to that of total particles for most samples, suggesting that the absorption of the total particles [a p (λ)] was dominated by a NAP (λ). The CDOM absorption spectra [a CDOM (λ)] of West Liaohe and Taizihe rivers were easily distinguished from those of Hunhe, Liaohe, and East Liaohe rivers. Redundancy analysis indicated that absorption by optically active substances and anthropogenic nutrient disturbances probably resulted in the diversity of water quality parameters. The environmental variables including dissolved organic carbon, total alkalinity (TAlk), and total nitrogen (TN) had a significant correlation with CDOM absorption at 440 nm [a CDOM (440)]. There was almost no correlation between a p (λ) and chlorophyll a, TN, total phosphorus, and TAlk. Moreover, total copper ion concentration and mercury ion concentration had a strong correlation with a p (440), a p (675), a NAP (440), and a NAP (675). The concentration of total aluminum ions exhibited a positive correlation with a p (675) and a NAP (675) (p CDOM (440). Furthermore, the interaction between metal ions and optically active substances provided an insight into particulates and CDOM properties linked to water quality characteristics for rivers in semiarid areas.

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

    Science.gov (United States)

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

    2014-01-01

    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 suicide attempts, N SU , was found ( ρ > 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.

  9. Concentrations of trace elements and compounds in the airborne suspended particulate matter in Cleveland, Ohio, from August 1971 to August 1972 and their dependence on wind direction: Complete data listing and concentration roses

    Science.gov (United States)

    King, R. B.; Neustadter, H. E.

    1976-01-01

    Concentrations of 75 chemical constituents in the airborne particulate matter were measured in Cleveland, Ohio during 1971 and 1972. Daily values, maxima, geometric means and their standard deviations covering a 1-year period (45 to 50 sampling days) at each of 16 sites are presented on microfiche for 60 elements, and for a lesser number of days for 10 polycyclic aromatic hydrocarbon compounds (PAH), the aliphatic hydrocarbon compounds (AH) as a group and carbon. In addition, concentration roses showing directional properties are presented for 39 elements, 10 PAH and the AH as a group. The elements (except carbon) are shown both in terms of concentration and percentage of the suspended particulate matter.

  10. Contribution of suspended particulate matter and zooplankton to MeHg contamination of the food chain in mid-northern Quebec (Canada) reservoirs

    International Nuclear Information System (INIS)

    Plourde, Y.; Lucotte, M.; Pichet, P.

    1997-01-01

    The high increase in mercury (Hg) concentrations in fish following the creation of hydroelectric reservoirs was discussed. Flooded forest soils are a major source of mercury contamination of fish after impoundment. Flooding stimulates bacterial activity in the humic horizon of soils and results in the transformation of inorganic mercury into methyl mercury (MeHg), the most toxic form of mercury. The reservoirs of the La Grande hydroelectric complex at James Bay in northern Quebec were sampled and compared to neighbouring natural lakes. Sampling was carried out in 1992 during June, August and September. Results of the analysis revealed an increase in the MeHg concentrations in zooplankton and suspended particulate matter (SPM); mean concentrations were about 5 times higher in the reservoirs than in neighbouring lakes. Although the process is not well understood, it is believed that the MeHg is transferred up the food chain which accounts, in part, for MeHg contamination of fishes. 45 refs., 9 figs

  11. The dynamics of suspended particulate matter (SPM) and chlorophyll-a from intratidal to annual time scales in a coastal turbidity maximum

    Science.gov (United States)

    van der Hout, C. M.; Witbaard, R.; Bergman, M. J. N.; Duineveld, G. C. A.; Rozemeijer, M. J. C.; Gerkema, T.

    2017-09-01

    The analysis of 1.8 years of data gives an understanding of the response to varying forcing of suspended particulate matter (SPM) and chlorophyll-a (CHL-a) in a coastal turbidity maximum zone (TMZ). Both temporal and vertical concentration variations in the near-bed layer (0-2 m) in the shallow (11 m deep) coastal zone at 1 km off the Dutch coast are shown. Temporal variations in the concentration of both parameters are found on tidal and seasonal scales, and a marked response to episodic events (e.g. storms). The seasonal cycle in the near-bed CHL-a concentration is determined by the spring bloom. The role of the wave climate as the primary forcing in the SPM seasonal cycle is discussed. The tidal current provides a background signal, generated predominantly by local resuspension and settling and a minor role is for advection in the cross-shore and the alongshore direction. We tested the logarithmic Rouse profile to the vertical profiles of both the SPM and the CHL-a data, with respectively 84% and only 2% success. The resulting large percentage of low Rouse numbers for the SPM profiles suggest a mixed suspension is dominant in the TMZ, i.e. surface SPM concentrations are in the same order of magnitude as near-bed concentrations.

  12. Investigation of the UK37' vs. SST relationship for Atlantic Ocean suspended particulate alkenones: An alternative regression model and discussion of possible sampling bias

    Science.gov (United States)

    Gould, Jessica; Kienast, Markus; Dowd, Michael

    2017-05-01

    Alkenone unsaturation, expressed as the UK37' index, is closely related to growth temperature of prymnesiophytes, thus providing a reliable proxy to infer past sea surface temperatures (SSTs). Here we address two lingering uncertainties related to this SST proxy. First, calibration models developed for core-top sediments and those developed for surface suspended particulates organic material (SPOM) show systematic offsets, raising concerns regarding the transfer of the primary signal into the sedimentary record. Second, questions remain regarding changes in slope of the UK37' vs. growth temperature relationship at the temperature extremes. Based on (re)analysis of 31 new and 394 previously published SPOM UK37' data from the Atlantic Ocean, a new regression model to relate UK37' to SST is introduced; the Richards curve (Richards, 1959). This non-linear regression model provides a robust calibration of the UK37' vs. SST relationship for Atlantic SPOM samples and uniquely accounts for both the fact that the UK37' index is a proportion, and so must lie between 0 and 1, as well as for the observed reduction in slope at the warm and cold ends of the temperature range. As with prior fits of SPOM UK37' vs. SST, the Richards model is offset from traditional regression models of sedimentary UK37' vs. SST. We posit that (some of) this offset can be attributed to the seasonally and depth biased sampling of SPOM material.

  13. Long-term ambient concentrations of total suspended particulates and oxidants as related to incidence of chronic disease in California Seventh-Day Adventists

    Energy Technology Data Exchange (ETDEWEB)

    Abbey, D.E.; Mills, P.K.; Petersen, F.F.; Beeson, W.L. (Loma Linda Univ. School of Medicine, CA (United States))

    1991-08-01

    Cancer incidence and mortality in a cohort of 6000 nonsmoking California Seventh-Day Adventists were monitored for a 6-year period, and relationships with long-term cumulative air pollution were observed. Total suspended particulates (TSP) and ozone were measured in terms of numbers of hours in excess of several threshold levels corresponding to national standards as well as mean concentration. For all malignant neoplasms among females, risk increased with increasing exceedance frequencies of all thresholds of TSP except the lowest one, and those increased risks were highly statistically significant. For respiratory cancers, increased risk was associated with only one threshold of ozone, and this result was of borderline significance. Respiratory disease symptoms were assessed in 1977 and again in 1987 using the National Heart, Lung and Blood Institute respiratory symptoms questionnaire on a subcohort of 3914 individuals. Multivariate analyses which adjusted for past and passive smoking and occupational exposures indicated statistically significantly elevated relative risks ranging up to 1.7 for incidence of asthma, definite symptoms of airway obstructive disease, and chronic bronchitis with TSP in excess of all thresholds except the lowest one but not for any thresholds of ozone. A trend association was noted between the threshold of 10 pphm ozone and incidence of asthma. These results are presented within the context of standards setting for these constituents of air pollution.

  14. Long-term ambient concentrations of total suspended particulates and oxidants as related to incidence of chronic disease in California Seventh-Day Adventists.

    Science.gov (United States)

    Abbey, D E; Mills, P K; Petersen, F F; Beeson, W L

    1991-08-01

    Cancer incidence and mortality in a cohort of 6000 nonsmoking California Seventh-Day Adventists were monitored for a 6-year period, and relationships with long-term cumulative ambient air pollution were observed. Total suspended particulates (TSP) and ozone were measured in terms of numbers of hours in excess of several threshold levels corresponding to national standards as well as mean concentration. For all malignant neoplasms among females, risk increased with increasing exceedance frequencies of all thresholds of TSP except the lowest one, and those increased risks were highly statistically significant. For respiratory cancers, increased risk was associated with only one threshold of ozone, and this result was of borderline significance. Respiratory disease symptoms were assessed in 1977 and again in 1987 using the National Heart, Lung and Blood Institute respiratory symptoms questionnaire on a subcohort of 3914 individuals. Multivariate analyses which adjusted for past and passive smoking and occupational exposures indicated statistically significantly (p less than 0.05) elevated relative risks ranging up to 1.7 for incidence of asthma, definite symptoms of airway obstructive disease, and chronic bronchitis with TSP in excess of all thresholds except the lowest one but not for any thresholds of ozone. A trend association (p = 0.056) was noted between the threshold of 10 pphm ozone and incidence of asthma. These results are presented within the context of standards setting for these constituents of air pollution.

  15. Particulate air pollution, with emphasis on traffic generated aerosols

    DEFF Research Database (Denmark)

    Fauser, Patrik

    constitute each about 5 wt-% of the collected suspended particulate matter in inner city air. The particle size distribution shows that 92 % of the mass of airborne particulate tire debris have aerodynamic diameters smaller than 1 µm. The mean aerodynamic diameter is about 1 µm for the bitumen particles...... % of this concentration derives from adsorbed particles on both leaf sides. The remainder is either respired through stomata or incorporated in the epicuticular wax layer. The fact that a substantial amount of the airborne tire and bitumen particles occur in the submicron range permits long range transportation...

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

    Directory of Open Access Journals (Sweden)

    Bing Han

    2016-03-01

    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.

  17. Multi-temporal dynamics of suspended particulate matter in a macro-tidal river Plume (the Gironde) as observed by satellite data

    Science.gov (United States)

    Constantin, Sorin; Doxaran, David; Derkacheva, Anna; Novoa, Stéfani; Lavigne, Héloïse

    2018-03-01

    The Gironde River plume area is unique in terms of Suspended Particulate Matter (SPM) dynamics. Multiple factors contribute to the variations of SPM at multiple time scales, from river outputs to wind stress, currents and tidal cycles. The formation and evolution of the Maximum Turbidity Zone (MTZ) inside the estuary also plays a significant role. Thus, detailed analyses and monitoring of the region is important for better understanding the mechanisms governing the turbid plume dynamics, for proper future management and monitoring of SPM export from the estuary to the coastal ocean. In this study we use an unprecedented volume of satellite data to capture and better understand the dynamics of the river plume. We combine two types of satellite information in order to achieve these goals: data collected by the Moderate Resolution Imaging Spectroradiometer (MODIS) and the Spinning Enhanced Visible and Infrared Imager (SEVIRI) sensors. The integrated information allows accounting for multiple time scales, i.e. from seasonal to diurnal cycles. We show and parameterize the overall effects of river discharge rates over the plume extension. Seasonal variations are also analyzed and an overall relationship between river discharge rates and plume magnitude is computed. For the first time, we clearly observe and explain the diurnal cycle of SPM dynamics in the river plume. Despite the limited capabilities of the SEVIRI sensor, geostationary data was successfully used to derive such information and results similar to in-situ datasets were obtained. The same patterns are observed, with significant increase in SPM plume during spring/ebb tide periods. Results from our study can be further used to refine sediment transport models and to gain a better perspective on the ecological implications of the sediment output in the continental shelf area.

  18. Remediation of internal phosphorus loads with modified clays, influence of fluvial suspended particulate matter and response of the benthic macroinvertebrate community.

    Science.gov (United States)

    Yin, Hongbin; Douglas, Grant B; Cai, Yongjiu; Liu, Cheng; Copetti, Diego

    2018-01-01

    Clay-based phosphorus (P) sorbents have been increasingly used as geoengineering materials for the management sediment-derived internal P loading in eutrophic lakes. However, the long-term behavior of these sorbents has remained elusive along with their response to burial under suspended particulate matter (SPM), and their effect on macroinvertebrate communities occupying dynamic regions at the sediment-water interface of shallow and turbid lakes. In this study, field mesocosm experiments were undertaken in Lake Chaohu, China, to study the effects of the application of lanthanum-modified bentonite (LMB) and thermally-modified calcium-rich attapulgite (TCAP) on sediment internal P loading and to assess their influence on macroinvertebrate community structure. A complementary laboratory core incubation study was also undertaken to investigate the effects of SPM deposition on LMB and TCAP performance. In the field, both LMB and TCAP effectively intercepted P released from sediment for up to five months. A P fractionation analysis indicated that LMB and TCAP application results in a substantial increase in inert P fractions in sediment. Laboratory studies indicated that deposition of SPM may increase in mobile P both in the upper sediment and across the new post-SPM deposition sediment-water interface. Importantly, a comparison of sediment chemical extractions and estimated P fluxes suggests that chemically-defined forms of P in the sediment may be used as a proxy to estimate the net sediment P flux. Significantly, the surficial application of either LMB or TCAP did not cause negative effects on macroinvertebrate communities. This study indicates that to sustain a low P flux across the sediment-water interface in shallow, turbid lakes, repeat dosing of geoengineering materials, temporally aligned to the deposition of fluvial SPM, may be required. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Analysis of Suspended Particulate Matter and Its Drivers in Sahelian Ponds and Lakes by Remote Sensing (Landsat and MODIS: Gourma Region, Mali

    Directory of Open Access Journals (Sweden)

    Elodie Robert

    2017-12-01

    Full Text Available The Sahelian region is characterized by significant variations in precipitation, impacting water quantity and quality. Suspended particulate matter (SPM dynamics has a significant impact on inland water ecology and water resource management. In-situ data in this region are scarce and, consequently, the environmental factors triggering SPM variability are yet to be understood. This study addresses these issues using remote sensing optical data. Turbidity and SPM of the Agoufou Lake in Sahelian Mali were measured from October 2014 to present, providing a large range of `values (SPM ranging from 106 to 4178 mg/L. These data are compared to satellite reflectance from Landsat (ETM+, OLI and MODIS (MOD09GQ, MYD09GQ. For each of these sensors, a spectral band in the near infrared region is found to be well suited to retrieve turbidity and SPM, up to very high values (R2 = 0.70 seldom addressed by remote sensing studies. The satellite estimates are then employed to assess the SPM dynamics in the main lakes and ponds of the Gourma region and its links to environmental and anthropogenic factors. The main SPM seasonal peak is observed in the rainy season (June to September in relation to precipitation and sediment transport. A second important peak occurs during the dry season, highlighting the importance of resuspension mechanisms in maintaining high values of SPM. Three different periods are observed: first, a relatively low winds period in the early dry season, when SPM decreases rapidly due to deposition; then, a period of wind-driven resuspension in January‒March; and lastly, an SPM deposition period in April–May, when the monsoon replaces the winter trade wind. Overall, a significant increase of 27% in SPM values is observed between 2000 and 2016 in the Agoufou Lake. The significant spatio-temporal variability in SPM revealed by this study highlights the importance of high resolution optical sensors for continuous monitoring of water quality in

  20. Satellite assessment of the coupling between in water suspended particulate matter and mud banks dynamics over the French Guiana coastal domain

    Science.gov (United States)

    Vantrepotte, V.; Gensac, E.; Loisel, H.; Gardel, A.; Dessailly, D.; Mériaux, X.

    2013-07-01

    Particulate suspended matter concentration (SPM) were estimated over a 8 year time period (2002-2010) in the coastal waters of French Guiana from a regional algorithm applied to the MODIS monthly reflectance measurements. Comparison between SPOT images and MODIS-SPM maps revealed the strong spatio-temporal coupling between in water SPM and the dynamics of local (i.e. Kourou and Cayenne) mud banks. Highest MODIS SPM values (>13 g m-3 approximately) can be significantly associated with the subtidal part of the banks as well as to the related turbid plume. The migration of these mud banks induces strong interannual changes in SPM reaching up to 6% year-1 within increasing and decreasing patchy areas distributed alternatively along the coastline of French Guiana. Mud banks migration rates derived from MODIS SPM data reach in average about 2 km year-1 in agreement with previous studies. The MODIS time series have allowed for a detailed description of the seasonality and interannual variations in the in-water SPM loads. Seasonal changes in SPM are related to the onset of the trade wind season. Marked non-linear patterns including a sharp evolution in the SPM values around 2005 as well as additional high frequency modulations have been emphasized within the upward and downward SPM trend regions. Concurrent temporal variations in the frequency of northward swells (favoring mud banks migration and reworking) as well as interannual changes in the amount of sediment delivered by the Amazon River have been shown to play a major role in the SPM temporal patterns observed in the French Guiana coastal waters. Our results clearly demonstrate the advantage for ocean color data to describe mud banks dynamics through the assessment of in water SPM temporal variability.

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

    Directory of Open Access Journals (Sweden)

    Đorđević Amelija

    2016-01-01

    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

  2. Exposure to in-vehicle respirable particulate matter in passenger vehicles under different ventilation conditions and seasons

    Directory of Open Access Journals (Sweden)

    Suresh Jain

    2017-03-01

    Full Text Available This study presents the in-vehicle particulate matter (PM concentration in a number of passenger vehicles under various ventilation modes, land use land cover (LULC in different seasons in megacity Delhi, India. In-vehicle monitoring was conducted in buses, cars and autos (three-wheeler using air-conditioned (AC and Non-AC during peak and off-peak hours. The site selected is a ∼15 km long stretch from Punjabi Bagh to Safdarjung Hospital, based on diversity in LULC, availability of vehicles and heavy traffic flow along the direction of travelling. In-vehicle PM was measured using GRIMM aerosol spectrometer and categorised in three classes (PM1, PM2.5 and PM10. The study found that concentration of PM1, PM2.5 and PM10 were significantly (p ≤ 0.05 higher in winters as compared to summers. It was observed that PM concentration was significantly (p ≤ 0.05 higher in Non-AC travel modes compared to AC modes. PM concentrations were high near industrial and commercial areas and during traffic congestion showing the influence of LULC. It is also important to highlight that PM1, PM2.5 and PM10 concentrations were significantly (p ≤ 0.05 higher in case of taxis (cars compared to personal cars which varied from 2.5 to 3.5 times higher in case of AC mode and ∼1.5 times in case of Non-AC mode. Exposures to PM concentration were highest in case of Non-AC bus compared AC-Bus, Non-AC cars, autos and AC-cars. PM concentrations in case of autos and Non-AC cars were almost comparable without any significant (p > 0.05 difference. Regression analysis showed significant correlation between ambient and in-vehicle concentration for PM2.5. Regional deposition fractions were calculated using International Commission on Radiological Protection model to show the deposition in head air-pass, trachea-bronchial and alveolar regions. It was found that deposition of PM1 was highest in the alveolar region.

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

    Directory of Open Access Journals (Sweden)

    Spyridon Loridas

    2013-08-01

    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.

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

    Science.gov (United States)

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

    2016-03-15

    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

  5. Using VIIRS/NPP and MODIS/Aqua data to provide a continuous record of suspended particulate matter in a highly turbid inland lake

    Science.gov (United States)

    Cao, Zhigang; Duan, Hongtao; Shen, Ming; Ma, Ronghua; Xue, Kun; Liu, Dong; Xiao, Qitao

    2018-02-01

    Inland lakes are generally an important source of drinking water, and information on their water quality needs to be obtained in real time. To date, Moderate-resolution imaging spectroradiometer (MODIS) data have played a critical, effective and long-term role in fulfilling this function. However, the MODIS instruments on board both the Terra and Aqua satellites have operated beyond their designed five-year mission lifespans (Terra was launched in 1999, whereas Aqua was launched in 2002), and these instruments may stop running at any time in the near future. The Visible Infrared Imager Radiometer Suite (VIIRS) on board the Suomi National Polar-Orbiting Partnership (Suomi NPP, which was launched in Oct 2011) is expected to provide a consistent, long-term data record and continue the series of observations initiated by MODIS. To date, few evaluations of the consistency between VIIRS and MODIS have been conducted for turbid inland waters. In this study, we first used synchronous MODIS/Aqua and VIIRS/NPP data (±1 h) collected during 2012-2015 to evaluate the consistency of Rayleigh-corrected reflectance (Rrc) observations over Lake Hongze (the fourth-largest freshwater lake in China), since accurate remote sensing reflectance (Rrs) values cannot be acquired over turbid inland waters. Second, we used recently developed algorithms based on Rrc in the red band to estimate the concentrations of suspended particulate matter (SPM) from MODIS/Aqua and VIIRS/NPP data. Finally, we assessed the consistency of the SPM products derived from MODIS/Aqua and VIIRS/NPP. The results show the following. (1) The differences in Rrc among the green (VIIRS 551 nm and MODIS 555 nm) and red bands (VIIRS 671 nm and MODIS 645 nm) indicate a satisfactory consistency, and the unbiased percentage difference (UPD) is MODIS 859 nm and VIIRS 862 nm) indicate relatively large differences (UPD = 21.84%). (2) The satellite-derived SPM products obtained using MODIS/Aqua and VIIRS/NPP have a satisfactory

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

    Directory of Open Access Journals (Sweden)

    Stéfani Novoa

    2017-01-01

    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

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

    Science.gov (United States)

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

    2017-10-15

    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 seasons

  8. Comparison of laser-light diffraction method with other methods of analyzing the particle size distribution in suspensions of latex, pollen, and quartz, and in suspended particulate matter in river water

    International Nuclear Information System (INIS)

    Heyn, R.D.; Zimmermann, H.U.

    1983-01-01

    This report gives an idea of different methods being used for the particle size analysis, including a laser light diffraction method and an image analysis method. These comparing measurements have been carried out with suspensions consisting of fresh water and standard particles, ranging between 1 and 100 μm, as well as with suspended particulate matter of the Elbe river. As to standard particles, statistical errors are subject to the width of the size distribution. When using the light diffraction method, the errors vary between 0,7 and 16%, however, when applying the image analysis method, they range between 0,5 and 26%. As a result of the measurements of the suspended particulate matter of the Elbe river, a statistical error of 21% has occured with regard to the image analysis method, whilst the light diffraction method has shown an error of about 4 - 11%. Possible reasons for systematical and random errors have been discussed as to both of these methods. (orig.) [de

  9. Chronic obstructive pulmonary disease symptom effects of long-term cumulative exposure to ambient levels of total suspended particulates and sulfur dioxide in California Seventh-Day Adventist residents

    Energy Technology Data Exchange (ETDEWEB)

    Euler, G.L.; Abbey, D.E.; Magie, A.R.; Hodgkin, J.E.

    1987-07-01

    Risk of chronic obstructive pulmonary disease symptoms due to long-term exposure to ambient levels of total suspended particulates (TSP) and sulfur dioxide (SO/sub 2/) symptoms was ascertained using the National Heart, Lung, and Blood Institute (NHLBI) respiratory symptoms questionnaire on 7445 Seventh-Day Adventists. They were non-smokers, at least 25 yr of age, and had lived 11 yr or more in areas ranging from high to low photochemical air pollution in California. Participant cumulative exposures to each pollutant in excess of four thresholds were estimated using monthly residence zip code histories and interpolated dosages from state air monitoring stations. These pollutant thresholds were entered individually and in combination in multiple logistic regression analyses with eight covariables including passive smoking. Statistically significant associations with chronic symptoms were seen for: SO/sub 2/ exposure above 4 pphm (104 mcg/m3), (p = .03), relative risk 1.18 for 500 hr/yr of exposure; and for total suspended particulates (TSP) above 200 mcg/m3, (p less than .00001), relative risk of 1.22 for 750 hr/yr.

  10. In-situ partitioning and bioconcentration of polycyclic aromatic hydrocarbons among water, suspended particulate matter, and fish in the Dongjiang and Pearl Rivers and the Pearl River Estuary, China

    International Nuclear Information System (INIS)

    Li, Haiyan; Lu, Lei; Huang, Wen; Yang, Juan; Ran, Yong

    2014-01-01

    Highlights: • PAHs are relatively higher in marine fish than in freshwater fish. • PAHs respectively show significant correlations with DOC, POC, and Chl a. • The log K oc for PAHs is one order magnitude higher than the predicted. • The log BCF values in fish and their tissues are nonlinear in respect to log K ow . • Lipid is related to PAHs in freshwater fish, but not in marine fishes. - Abstract: The partitioning and bioaccumulation of polycyclic aromatic hydrocarbons (PAHs) in water, suspended particulate matter (SPM), and fish samples from the Dongjiang River (DR), Pearl River (PR), and the Pearl River Estuary (PRE) were examined. Although PAHs are much lower in PRE than in DR or PR, PAHs in some fish species are significantly higher in PRE than in DR or PR. Aqueous or particulate PAHs respectively show significant correlations with dissolved organic carbon, particulate organic matter, and chlorophyll a, suggesting that biological pumping effect regulates their distribution. The in situ partitioning coefficients (log K oc ) for PAHs are one order magnitude higher than the empirical log K oc –log K ow correlation. The bioconcentration factor (BCF) is slightly higher for the marine fish than for the freshwater fish. The above phenomena indicate that BCF may vary due to the diversity of fish species, feeding habits, and metabolism of PAHs in fish

  11. 42 CFR 84.174 - Respirator containers; minimum requirements.

    Science.gov (United States)

    2010-10-01

    ... 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..., durable container bearing markings which show the applicant's name, the type of respirator it contains...

  12. Distribution and transportation of suspended sediment

    International Nuclear Information System (INIS)

    Schubel, J.R.

    1975-01-01

    A number of studies of the distribution and character of suspended matter in the waters of the Atlantic shelf have documented the variations in the concentration of total suspended matter in both time and space. Very little is known, however, about the ultimate sources of inorganic suspended matter, and even less is known about the routes and rates of suspended sediment transport in shelf waters. Suspended particulate matter constitutes a potential vehicle for the transfer of energy-associated contaminants, radionuclides and oil, back to the coast and therefore to man. The concentrations of total suspended matter in shelf waters are typically so low, however, that the mechanism is ineffective. Studies of suspended particulate matter have a high scientific priority, but in this investigator's opinion the state of knowledge is adequate for preparation of the environmental impact statements that would be required for siting of offshore nuclear power plants and for oil drilling on the Atlantic Continental Shelf

  13. Lithogenic sources, composition and intra-annual variability of suspended particulate matter supplied from rivers to the Northern Galician Rias (Bay of Biscay)

    Science.gov (United States)

    Bernárdez, Patricia; Prego, Ricardo; Filgueiras, Ana Virginia; Ospina-Álvarez, Natalia; Santos-Echeandía, Juan; Álvarez-Vázquez, Miguel Angel; Caetano, Miguel

    2017-12-01

    Scarce research about small European rivers from non-human impacted areas to determine their natural background state has been undertaken. During the annual hydrological cycle of 2008-9 the patterns of particulate supply (SPM, POC, PON, Al, Cd, Co, Cr, Cu, Fe, Ni, Pb, V, Zn) from the rivers Sor, Mera Landro, Lourido and Landoi to the Northern Galician Rias (SW Bay of Biscay) were tackled. No differences in the composition of the SPM were detected for the studied rivers regarding Al, Fe and POC but the relative percentage of particulate trace elements (PTE) discriminate the rivers. So, Cr, Co and Ni in the Lourido, and Landoi rivers, and Cu in the Mera River, are controlled by watershed minerals of Ortegal Geological Complex while for the rest rivers PTE are by granitic and Ollo de Sapo bedrock watershed. Therefore, the imprint of PTE in the parental rocks of the river basins is reflected on the coastal sediments of the Rias. The main process controlling the dynamics and variations of chemical elements in the particulate form is the river discharge. This fact exemplifies that these rivers presents a natural behavior not being highly influenced by anthropogenic activities.

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

    Directory of Open Access Journals (Sweden)

    Aine Marie Gormley-Gallagher

    Full Text Available 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.

  15. REE in suspended particulate matter and sediment of the Zuari estuary and adjacent shelf, western India: Influence of mining and estuarine turbidity

    Digital Repository Service at National Institute of Oceanography (India)

    Shynu, R.; Rao, V.P.; Parthiban, G.; Balakrishnan, S.; Narvekar, T.; Kessarkar, P.M.

    in the development of ETM in the lower estuary (Rao et al., 2011). As a consequence bottom sediment may have been re-suspended, thereby increasing SPM and REE in the water column and mixed up with the sediment brought by the river. In other words, the REE.... Seminar Volume on Earth Resources for Goa’s Development. Geological Survey of India, pp. 1-13. Goldstein, S.J., Jacobsen, S.B., 1988. Rare earth elements in river waters. Earth Planetary Science Letters 89, 35-47. Govindaraju, K., 1994. Compilation...

  16. 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

    Science.gov (United States)

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

    2016-04-01

    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

  17. Kinetic box models for the uptake of radionuclides and heavy metals by suspended particulate matter: equivalence between models and its implications

    International Nuclear Information System (INIS)

    Barros, H.; Abril, J.M.

    2008-01-01

    In recent years an increasing experimental effort has been paid to the study of the sorption process of radionuclides and heavy metals by particulate matter in aquatic environments. This has led to the development of different kinetic box models. Most of them are variations of two basic approaches: one containing several (up to three) parallel reactions while the other involves consecutive reactions. All the reactions are reversible (irreversibility is contained as a particular case) with concentration independent coefficients. The present work provides analytical solutions and demonstrates that both approaches are mathematically equivalent. That is, both models produce the same analytical solution for the uptake curve (time course of the concentrations in the dissolved phase), which is illustrated using literature data. This result unifies the description of the observed behaviour, but it brings up the question of the physical meaning of the involved coefficients. Finally, the mathematical relationship developed here serves to discuss some limitations found in recent attempts in literature devoted to distinguish the actual uptake mechanism

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

    Science.gov (United States)

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

    2017-04-01

    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

  19. 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).

    Science.gov (United States)

    Lee, Jung-Ho; Birch, Gavin F

    2016-04-01

    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.

  20. Multi-residue determination of the sorption of illicit drugs and pharmaceuticals to wastewater suspended particulate matter using pressurised liquid extraction, solid phase extraction and liquid chromatography coupled with tandem mass spectrometry.

    Science.gov (United States)

    Baker, David R; Kasprzyk-Hordern, Barbara

    2011-11-04

    Presented is the first comprehensive study of drugs of abuse on suspended particulate matter (SPM) in wastewater. Analysis of SPM is crucial to prevent the under-reporting of the levels of analyte that may be present in wastewater. Analytical methods to date analyse the aqueous part of wastewater samples only, removing SPM through the use of filtration or centrifugation. The development of an analytical method to determine 60 compounds on SPM using a combination of pressurised liquid extraction, solid phase extraction and liquid chromatography coupled with tandem mass spectrometry (PLE-SPE-LC-MS/MS) is reported. The range of compounds monitored included stimulants, opioid and morphine derivatives, benzodiazepines, antidepressants, dissociative anaesthetics, drug precursors, and their metabolites. The method was successfully validated (parameters studied: linearity and range, recovery, accuracy, reproducibility, repeatability, matrix effects, and limits of detection and quantification). The developed methodology was applied to SPM samples collected at three wastewater treatment plants in the UK. The average proportion of analyte on SPM as opposed to in the aqueous phase was 10% with regard to methadone, EDDP, EMDP, BZP, fentanyl, nortramadol, norpropoxyphene, sildenafil and all antidepressants (dosulepin, amitriptyline, nortriptyline, fluoxetine and norfluoxetine). Consequently, the lack of SPM analysis in wastewater sampling protocol could lead to the under-reporting of the measured concentration of some compounds. Copyright © 2011 Elsevier B.V. All rights reserved.

  1. The Diesel Exhaust in Miners Study: III. Interrelations between respirable elemental carbon and gaseous and particulate components of diesel exhaust derived from area sampling in underground non-metal mining facilities.

    Science.gov (United States)

    Vermeulen, Roel; Coble, Joseph B; Yereb, Daniel; Lubin, Jay H; Blair, Aaron; Portengen, Lützen; Stewart, Patricia A; Attfield, Michael; Silverman, Debra T

    2010-10-01

    Diesel exhaust (DE) has been implicated as a potential lung carcinogen. However, the exact components of DE that might be involved have not been clearly identified. In the past, nitrogen oxides (NO(x)) and carbon oxides (CO(x)) were measured most frequently to estimate DE, but since the 1990s, the most commonly accepted surrogate for DE has been elemental carbon (EC). We developed quantitative estimates of historical exposure levels of respirable elemental carbon (REC) for an epidemiologic study of mortality, particularly lung cancer, among diesel-exposed miners by back-extrapolating 1998-2001 REC exposure levels using historical measurements of carbon monoxide (CO). The choice of CO was based on the availability of historical measurement data. Here, we evaluated the relationship of REC with CO and other current and historical components of DE from side-by-side area measurements taken in underground operations of seven non-metal mining facilities. The Pearson correlation coefficient of the natural log-transformed (Ln)REC measurements with the Ln(CO) measurements was 0.4. The correlation of REC with the other gaseous, organic carbon (OC), and particulate measurements ranged from 0.3 to 0.8. Factor analyses indicated that the gaseous components, including CO, together with REC, loaded most strongly on a presumed 'Diesel exhaust' factor, while the OC and particulate agents loaded predominantly on other factors. In addition, the relationship between Ln(REC) and Ln(CO) was approximately linear over a wide range of REC concentrations. The fact that CO correlated with REC, loaded on the same factor, and increased linearly in log-log space supported the use of CO in estimating historical exposure levels to DE.

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

    Directory of Open Access Journals (Sweden)

    Prabhat Kumar Rai

    2015-12-01

    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.

  3. Suspended ceilings

    Energy Technology Data Exchange (ETDEWEB)

    Talamo, C.

    1991-05-01

    The retrofitting of existing conventional ceiling systems to suspended ceiling type systems represents an interesting energy savings solution since this method, in addition to providing additional protection against space heat loss and thermal bridges, also creates the possibility of housing, in the void, additional mechanical and electrical lines which may be necessary due to other savings interventions. This paper reviews the various suspended ceiling systems (e.g., those making use of mineral fibre, gypsum panels, wood, vermiculite, etc.) currently marketed in Europe, and reports, for each, some key technical, economic and architectural advantages which include thermal efficiency, noise abatement, as well as, resistance to fire and humidity. Information is also given on the relative installation and maintenance requirements.

  4. Impact of sound attenuation by suspended sediment on ADCP backscatter calibrations

    NARCIS (Netherlands)

    Sassi, M.G.; Hoitink, A.J.F.; Vermeulen, B.

    2012-01-01

    Although designed for velocity measurements, acoustic Doppler current profilers (ADCPs) are widely being used to monitor suspended particulate matter in rivers and in marine environments. To quantify mass concentrations of suspended matter, ADCP backscatter is generally calibrated with in situ

  5. Suspended particulate matter in railway coaches

    Science.gov (United States)

    Leutwyler, M.; Siegmann, K.; Monn, Ch

    Measurements of particles intercity connection in Switzerland. All trains are electrified and the indoor air quality is regulated by a mechanical ventilation system. In the smoker sections, pPAH levels were on average about 250 ng m -3, PM 10 levels about 950 μg m -3. In the non-smoker section, pPAH levels were about 45 ng m -3 and PM 10 levels about 210 μg m -3. Our observations suggest that smoking is the most important source of pPAH and PM 10. The spatial variation within the coaches indicates that pPAHs spread out from the smoker compartments into the non-smoker compartments. For PM 10, resuspended material may also be a source of airborne PM 10 but the contribution within this non-stop connection with most of the passengers being seated all the time was probably small. The influence of outdoor PM 10 and pPAH on indoor levels was negligible. Both pollutants, pPAH and PM 10 were largely elevated in the smoker as well as in the non-smoker compartments. Despite this fact, a questionnaire on the quality of travelling showed that most of the passengers felt well and only a small proportion felt uneasy.

  6. 23 Elemental Composition of Suspended Particulate Matter ...

    African Journals Online (AJOL)

    `123456789jkl''''#

    The samples were analysed by energy dispersive x-ray fluorescence. (EDXRF) and atomic absorption spectroscopy (AAS) for up to 10 elements. It was found that 66% of the ..... coefficients between the various crustal elements Ca, Ti, Mn, ...

  7. Seasonal and interannual variabilities of coccolithophore blooms in the Bay of Biscay and the Celtic Sea observed from a 18-year time-series of non-algal Suspended Particulate Matter images

    Science.gov (United States)

    Perrot, Laurie; Gohin, Francis; Ruiz-Pino, Diana; Lampert, Luis

    2016-04-01

    Coccolithophores belong to the nano-phytoplankton size-class and produce CaCO3 scales called coccoliths which form the «shell» of the algae cell. Coccoliths are in the size range of a few μm and can also be detached from the cell in the water. This phytoplankton group has an ubiquitous distribution in all oceans but blooms only in some oceanic regions, like the North East Atlantic ocean and the South Western Atlantic (Patagonian Sea). At a global scale coccolithopore blooms are studied in regard of CaCO3 production and three potential feedback on climate change: albedo modification by the way of dimethylsulfide (DMS) production and atmospheric CO2 source by calcification and a CO2 pump by photosynthesis. As the oceans are more and more acidified by anthropogenic CO2 emissions, coccolithophores generally are expected to be negatively affected. However, recent studies have shown an increase in coccolithophore occurrence in the North Atlantic. A poleward expansion of the coccolithophore Emiliana Huxleyi has also been pointed out. By using a simplified fuzzy method applied to a 18-year time series of SeaWiFS (1998-2002) and MODIS (2003-2015) spectral reflectance, we assessed the seasonal and inter-annual variability of coccolithophore blooms in the vicinity of the shelf break in the Bay of Biscay and the Celtic Sea After identification of the coccolith pixels by applying the fuzzy method, the abundance of coccoliths is assessed from a database of non-algal Suspended Particulate Matter (SPM). Although a regular pattern in the phenology of the blooms is observed, starting south in April in Biscay and moving northwards until July in Ireland, there is a high seasonal and interannual variability in the extent of the blooms. Year 2014 shows very low concentrations of detached coccoliths (twice less than average) from space and anomalies point out the maximum level in 2001. Non-algal SPM, derived from a procedure defined for the continental shelf, appears to be well

  8. 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

    Energy Technology Data Exchange (ETDEWEB)

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

    2001-05-20

    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

  9. Characterization and morphology of solids suspended in rain water

    International Nuclear Information System (INIS)

    Iturbe G, J.L.; Lopez M, B.E.; Torre O, J. De la

    2000-01-01

    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

  10. COPPER-DEPENDENT INFLAMMATION AND NUCLEAR FACTOR-KB ACTIVATION BY PARTICULATE AIR POLLUTION

    Science.gov (United States)

    Particulate air pollution causes increased cardiopulmonary morbidity and mortality, but the chemical determinants responsible for its biologic effects are not understood. We studied the effect of total suspended particulates collected in Provo, Utah, an area where an increase in ...

  11. Kuwaiti oil fires—Particulate monitoring

    Science.gov (United States)

    Husain, Tahir; Amin, Mohamed B.

    The total suspended particulate (TSP) matters using a high-volume sampler and inhalable particulate matters using PM-10 samplers were collected at various locations in the Eastern Province of Saudi Arabia during and after the Kuwaiti oil fires. The collected samples were analysed for toxic metals and oil hydrocarbon concentrations including some carcinogenic organic compounds in addition to gravimetric analysis. The concentration values of particulate matters were determined on a daily basis at Dhahran. Abqaiq, Rahima, Tanajib and Jubail locations. The analyses of the filters show a high concentration of the inhalable particulate at various locations, especially when north or northwest winds were blowing. It was found that the inhalable particulate concentration exceeded the Meteorology and Environmental Protection Administration (MEPA) permissible limit of 340 μg m- 3 at most of these locations during May-October 1991. A trend between the total suspended particulate and inhalable particulate measured concurrently at the same locations was observed and a regression equation was developed to correlate PM-10 data with the total suspended particulate data.

  12. Organic carbon budget for the eastern boundary of the North Atlantic subtropical gyre: major role of DOC in mesopelagic respiration.

    Science.gov (United States)

    Santana-Falcón, Yeray; Álvarez-Salgado, Xosé Antón; Pérez-Hernández, María Dolores; Hernández-Guerra, Alonso; Mason, Evan; Arístegui, Javier

    2017-08-31

    Transports of suspended particulate (POC susp ) and dissolved (DOC) organic carbon are inferred from a box-model covering the eastern boundary of the North Atlantic subtropical gyre. Corresponding net respiration rates (R) are obtained from a net organic carbon budget that is based on the transport estimates, and includes both vertical and lateral fluxes. The overall R in the mesopelagic layer (100-1500 m) is 1.6 ± 0.4 mmol C m -2 d -1 . DOC accounts for up to 53% of R as a result of drawdown of organic carbon within Eastern North Atlantic Central Water (ENACW) that is entrained into sinking Mediterranean Overflow Water (MOW) that leads to formation of Mediterranean water (MW) at intermediate depths (~900 m). DOC represents 90% of the respired non-sinking organic carbon. When converted into oxygen units, the computed net respiration rate represents less than half the oxygen utilization rates (OUR) reported for the mesopelagic waters of the subtropical North Atlantic. Mesoscale processes in the area, not quantified with our approach, could account in part for the OUR differences observed between our carbon budget and other published studies from the North Atlantic, although seasonal or interannual variability could also be responsible for the difference in the estimates.

  13. Respirator field performance factors

    International Nuclear Information System (INIS)

    Skaggs, B.J.; DeField, J.D.; Strandberg, S.W.; Sutcliffe, C.R.

    1985-01-01

    The Industrial Hygiene Group assisted OSHA and the NRC in measurements of respirator performance under field conditions. They reviewed problems associated with sampling aerosols within the respirator in order to determine fit factors (FFs) or field performance factor (FPF). In addition, they designed an environmental chamber study to determine the effects of temperature and humidity on a respirator wearer

  14. Distribution of lead-210 and polonium-210 between soluble and particulate phases in seawater

    International Nuclear Information System (INIS)

    Spencer, D.W.

    1975-01-01

    Results are reported from radiometric measurements of the distribution of 210 Pb and 210 Po in surface seawater and suspended particulate matter. Samples of plankton and sediments collected from some locations were also analyzed. Samples of seawater and suspended particulate matter were collected from stations located in the Gulf of Maine, the North Atlantic, and approximately 500 miles southwest of Gilbraltar. (U.S.)

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

    Directory of Open Access Journals (Sweden)

    Prabhat Kumar Rai

    2016-03-01

    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.

  16. Respirator studies for the Nuclear Regulatory Commission (NRC)

    International Nuclear Information System (INIS)

    Skaggs, B.J.; Fairchild, C.I.; DeField, J.D.; Hack, A.L.

    1985-01-01

    A project of the Health, Safety and Environment Division is described. The project provides the NRC with information of respiratory protective devices and programs for their licensee personnel. The following activities were performed during FY 1983: selection of alternate test aerosols for quality assurance testing of high-efficiency particulate air respirator filters; evaluation of MAG-1 spectacles for use with positive and negative-pressure respirators; development of a Manual of Respiratory Protection in Emergencies Involving Airborne Radioactive Materials, and technical assistance to NRC licensees regarding respirator applications. 2 references, 1 figure

  17. Evaluation of diesel particulate matter sampling techniques

    CSIR Research Space (South Africa)

    Pretorius, CJ

    2011-09-01

    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...

  18. Choosing the right respirator

    International Nuclear Information System (INIS)

    Bidwell, J.

    1997-01-01

    Selecting respirators to help protect workers from airborne contaminants can be a confusing process. The consequences of selecting the incorrect respirator can be intimidating, and worker safety and health may be dramatically and irreparably affected if an inappropriate respirator is chosen. When used in the workplace, a formal respiratory protection program must be established covering the basic requirements outlined in the OSHA Respiratory Protection Standard (29 CFR 1910.134). Education and training must be properly emphasized and conducted periodically. Maintenance, cleaning, and storage programs must be established and routinely followed for reusable respirators. The process of establishing a respiratory protection program can be broken down into four basic steps: Identify respiratory hazards and concentrations; understand the contaminants effects on workers' health; select appropriate respiratory protection; and train in proper respirator use and maintenance. These four steps are the foundation for establishing a basic respirator protection program. Be sure to consult state and federal OSHA requirements to ensure that the program complies. Leading industrial respirator manufacturers should be able to assist with on-site training and education in this four-step process, in addition to helping employers train their workers and conduct respirator fit testing

  19. Resuspension of particulate matter from grass and soil

    International Nuclear Information System (INIS)

    Garland, J.A.

    1979-05-01

    Measurements of resuspension of particulate matter from grassland and bare soil in Britain at controlled wind speeds are described in this report. The measurements were performed in an outdoor wind tunnel. Resuspension factors for a sub-micron powder deposited from the air on to 10m 2 of grass and soil and for a suspension of silt, sprayed on to a similar grass area, were similar. The resuspension factor declined as the reciprocal of time of wind exposure and increased as the square or cube of wind speed. An appreciable fraction of the resuspended tracer was in the respirable size range. A large fraction of the total material suspended from a small contaminated area deposited again within three metres. The strong dependence of deposition rates on particle size and the rapid deposition close to the source questions the extrapolation of small scale resuspension measurements to practical situations, suggesting that analysis of the concentrations of widely distributed tracers may usefully supplement resuspension measurements. Atmospheric concentrations of trace elements and the distribution of weapons fallout were used to deduce an upper limit for the resuspension factor for a fifteen year old deposit of 7 x 10 -11 m -1 . The fraction of deposited fallout resuspended during such a period cannot much exceed 10 per cent. (author)

  20. Disclosure and Fit Capability of the Filtering Facepiece Respirator.

    Science.gov (United States)

    Lofgren, Don J

    2018-05-01

    The filtering facepiece air-purifying respirator is annually purchased in the tens of millions and widely used for worker protection from harmful airborne particulates. The workplace consumers of this safety product, i.e., employers, workers, and safety and health professionals, have assurances of its effectiveness through the respirator certification and disclosure requirements of the National Institute for Occupational Safety and Health. However, the certification of a critical performance requirement has been missing for the approved filtering facepiece respirator since 1995: fit capability. Without this certification, consumers continue to be at risk of purchasing a respirator model that may fit a small percentage of the intended users. This commentary updates and expands an earlier one by this author, addresses the consequences of poorly fitting certified models on the market and lack of disclosure, and calls for further action by National Institute for Occupational Safety and Health to meet the needs and expectations of the consumer.

  1. Respiration in Aquatic Insects.

    Science.gov (United States)

    MacFarland, John

    1985-01-01

    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)

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

    Digital Repository Service at National Institute of Oceanography (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...

  3. Understanding particulate coating microstructure development

    Science.gov (United States)

    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.

  4. Amino sugars in suspended particulate matter from the Bay of ...

    Indian Academy of Sciences (India)

    Amino sugars (AS) are important constituents of organic matter. However ... about the molecular level characterization, distri- bution and ... tion about the dynamics, nutritive value, nature and degradation state of AS containing organic matter. 2. Material ..... carbohydrates and amino acids; Marine Chemistry 96. 155–184.

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

    Energy Technology Data Exchange (ETDEWEB)

    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)

    2000-07-01

    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.

  6. Suspended graphene variable capacitor

    OpenAIRE

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

    2016-01-01

    The tuning of electrical circuit resonance with a variable capacitor, or varactor, finds wide application with the most important being wireless telecommunication. We demonstrate an 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 in an ultra-thin structure. Large arrays compr...

  7. Quantitative evaluation of the protective effect of respirators

    International Nuclear Information System (INIS)

    Murata, Mikio

    1983-01-01

    The present status and related problems of the quantitative evaluation method for respirator efficiency are generally reviewed. As the introduction, the special features of various types of respirators are summarized, and the basic concept of leakage and the protection factor are explained. As for the quantitative measurement of the protective efficiency, the features of various existing man-test methods such as NaCl aerosol man-test, DOP (dioctyl phthalate) man-test, and SF 6 gas man-test are reviewed and discussed. As the important problems associated with those man-tests, the following aspects are discussed. The measurement of the aerosol concentration within masks; the calculation method for the protection factor; the effect of beards. The examples of measuring the protection factor are also explained for the following respirator systems: half mask respirator with a high efficiency filter; full face mask respirator with a high efficiency filter; demand mode and pressure-demand mode respirators; and mound suit with suspenders. Finally, the outline of the manual of respiratory protection published by NRC in 1976 is briefly reviewed. (Aoki, K.)

  8. Occurrence of trace elements in respirable coal dust

    International Nuclear Information System (INIS)

    Sahoo, B.N.

    1991-01-01

    Inhalation of fine particles of coal dust contributes significantly to the occurrence of the disease, pneumoconiosis, prevailing in coal mining community. It is not presently known whether only the coal dust or specific chemical compounds or synergistic effects of several compounds associated with respirable coal dust is responsible for the disease, pneumoconiosis. The present paper describes the quantitative determination of ten minor and trace elements in respirable coal dust particles by atomic absorption spectrophotometric methods. The respirable coal dust samples are collected at the mine atmosphere during drilling in coal scams by using Messrs. Casella's Hexlet apparatus specially designed and fitted with horizontal elutriator to collect the respirable coal dust fraction simulating as near as possible to the lung's retention of the coal miners. After destruction of organic matter by wet oxidation and filtering off clay and silica, Fe, Ca, Mg, Na, K, Mn, Cu, Zn, Cd, and Ni were determined directly in the resulting solution by atomic absorption spectrophotometric procedures. The results show that the trace metals are more acute in lower range of size spectrum. Correlation coefficient, enrichment factor and linear regression values and their inverse relationship between the slope and EF values suggest that, in general, the trace metals in respirable particulates are likely to be from coal derived source if their concentrations are likewise high in the coal. The trace metal analytical data of respirable particulates fitted well to the linear regressive equation. The results of the studies are of importance as it may throw some light on the respirable lung disease 'pneumoconiosis' which are predominant in coal mining community. (author). 13 refs., 6 tabs

  9. Elemental Spatiotemporal Variations of Total Suspended Particles in Jeddah City

    OpenAIRE

    Kadi, Mohammad W.

    2014-01-01

    Elements associated with total suspended particulate matter (TSP) in Jeddah city were determined. Using high-volume samplers, TSP samples were simultaneously collected over a one-year period from seven sampling sites. Samples were analyzed for Al, Ba, Ca, Cu, Mg, Fe, Mn, Zn, Ti, V, Cr, Co, Ni, As, and Sr. Results revealed great dependence of element contents on spatial and temporal variations. Two sites characterized by busy roads, workshops, heavy population, and heavy trucking have high lev...

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1996-10-01

    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}.

  11. Cattle respiration facility

    DEFF Research Database (Denmark)

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

    2012-01-01

    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...

  12. Quantitative respirator man-testing at Rocky Flats

    International Nuclear Information System (INIS)

    Leigh, J.D.

    The dioctyl phthalate quantitative respirator man-testing method used at Rocky Flats is outlined. Using this method, 93 persons trained to use self contained breathing equipment were tested with eight respiratory protective devices. Test results obtained with the seven devices using high efficiency particulate filters are compared to the results obtained with the self contained breathing equipment. Also comparison is made for these results to test results for 1667 other employees

  13. Quantitative respirator man-testing at Rocky Flats

    Energy Technology Data Exchange (ETDEWEB)

    Leigh, J. D.

    1978-01-01

    The dioctyl phthalate quantitative respirator man-testing method used at Rocky Flats is outlined. Using this method, 93 persons trained to use self contained breathing equipment were tested with eight respiratory protective devices. Test results obtained with the seven devices using high efficiency particulate filters are compared to the results obtained with the self contained breathing equipment. Also comparison is made for these results to test results for 1667 other employees.

  14. Characterisation of airborne particulate pollution in the Cu smelter and former mining town of Karabash, South Ural Mountains of Russia.

    Science.gov (United States)

    Williamson, B J; Udachin, V; Purvis, O W; Spiro, B; Cressey, G; Jones, G C

    2004-11-01

    Airborne total suspended particulates (TSP), dusts from smelter blast furnace and converter stacks, and filtrates of snow melt waters have been characterised in the Cu smelter and former mining town of Karabash, Russia. TSP was collected at sites up- and downwind of the smelter and large waste and tailings dumps (Oct. 2000 and July 2001). Methods for particle size, mineralogical and elemental determinations have been tested and described, and a new PSD-MicroSOURCE XRD technique developed for the mineralogical analysis of microsamples on filter substrates. TSP in downwind samples has a mean equivalent spherical diameter of 0.5 microm (s.d. = 0.2) and was found to be 100% respirable. The main element of human health/environmental concern, above Russian maximum permitted levels (1 microg m(-3), average over any time period), was Pb which was measured at 16-30 microg m(-3) in downwind samples. Individual particulates mainly consisted of complex mixtures of anglesite (PbSO4), Zn2SnO4 and poorly ordered Zn sulphates. From experimental and theoretical considerations, a high proportion of contained Pb, Zn, Cd and As in this material is considered to be in a readily bioavailable form. Chemical and mineralogical differences between the TSP, stack dusts and snow samples are discussed, as well as the implications for human and regional environmental health.

  15. Respirators. Does your face fit

    Energy Technology Data Exchange (ETDEWEB)

    Caro, N M; Else, D

    1981-04-01

    The authors carried out a survey of face sizes of men and women of four different ethnic origins and carried out face-seal leakage trials on four corresponding test panels. No single respirator design is likely to fit all members of the workforce, and it may be necessary to stock respirators from more than one manufacturers.Three or four different respirators or size of respirator may be needed. However, the use of lossely-fitting respirators such as Airsteam helmets could remove the necessity for exhaustive fitting procedures.

  16. Magnetically suspended railway

    Energy Technology Data Exchange (ETDEWEB)

    Guenther, C

    1977-07-28

    The invention concerns the emergency support of a magnetically suspended railway. On failure of the magnetic suspension/tracking system, the vehicles touch down on the rail configuration by means of emergency gliding elements like sliding shoes, skids, or the like. In doing this, the touch-down shock of the emergency gliding elements has to be limited to a force maximum as small as possible. According to the invention a spring-attenuator combination is used for this purpose, the spring characteristic being linear while the attenuator has a square-law characteristic for the compressing and a linear characteristic for the yielding motion. The force maximum thus achieved is exactly half the size of the physically smallest possible force maximum for an emergency gliding element springed without damping.

  17. 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

    Directory of Open Access Journals (Sweden)

    Cláudio Cardoso Marinho

    2010-06-01

    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

  18. Report Task 2.3: Particulate waste and turbidity in (marine) RAS

    OpenAIRE

    Kals, J.; Schram, E.; Brummelhuis, E.B.M.; Bakel, van, B.

    2006-01-01

    Particulate waste management and removal is one of the most problematic parts of recirculation aquaculture systems (RAS). Particulate waste and thereby turbidity originates from three major sources: fish (faeces), feed and biofilm (heterotrophic bacteria and fungi). Based on size and density there are roughly four categories of particulate waste: settable, suspended, floatable and fine or dissolved solids. Specific problems related to high turbidity are a decreasing feed intake by fish, causi...

  19. Pulmonary epithelial response in the rat lung to instilled Montserrat respirable dusts and their major mineral components.

    Science.gov (United States)

    Housley, D G; Bérubé, K A; Jones, T P; Anderson, S; Pooley, F D; Richards, R J

    2002-07-01

    The Soufriere Hills, a stratovolcano on Montserrat, started erupting in July 1995, producing volcanic ash, both from dome collapse pyroclastic flows and phreatic explosions. The eruptions/ash resuspension result in high concentrations of suspended particulate matter in the atmosphere, which includes cristobalite, a mineral implicated in respiratory disorders. To conduct toxicological studies on characterised samples of ash, together with major components of the dust mixture (anorthite, cristobalite), and a bioreactive mineral control (DQ12 quartz). Rats were challenged with a single mass (1 mg) dose of particles via intratracheal instillation and groups sacrificed at one, three, and nine weeks. Acute bioreactivity of the particles was assessed by increases in lung permeability and inflammation, changes in epithelial cell markers, and increase in the size of bronchothoracic lymph nodes. Data indicated that respirable ash derived from pyroclastic flows (20.1% cristobalite) or phreatic explosion (8.6% cristobalite) had minimal bioreactivity in the lung. Anorthite showed low bioreactivity, in contrast to pure cristobalite, which showed progressive increases in lung damage. Results suggests that either the percentage mass of cristobalite particles present in Montserrat ash was not sufficient as a catalyst in the lung environment, or its surface reactivity was masked by the non-reactive volcanic glass components during the process of ash formation.

  20. Respirable dust and respirable silica exposure in Ontario gold mines.

    Science.gov (United States)

    Verma, Dave K; Rajhans, Gyan S; Malik, Om P; des Tombe, Karen

    2014-01-01

    A comprehensive survey of respirable dust and respirable silica in Ontario gold mines was conducted by the Ontario Ministry of Labor during 1978-1979. The aim was to assess the feasibility of introducing gravimetric sampling to replace the assessment method which used konimeters, a device which gave results in terms of number of particles per cubic centimeter (ppcc) of air. The study involved both laboratory and field assessments. The field assessment involved measurement of airborne respirable dust and respirable silica at all eight operating gold mines of the time. This article describes the details of the field assessment. A total of 288 long-term (7-8 hr) personal respirable dust air samples were collected from seven occupational categories in eight gold mines. The respirable silica (α-quartz) was determined by x-ray diffraction method. The results show that during 1978-1979, the industry wide mean respirable dust was about 1 mg/m(3), and the mean respirable silica was 0.08 mg/m(3.)The mean% silica in respirable dust was 7.5%. The data set would be useful in future epidemiological and health studies, as well as in assessment of workers' compensation claims for occupational diseases such as silicosis, chronic obstructive pulmonary disease (COPD), and autoimmune diseases such as renal disease and rheumatoid arthritis.

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

    DEFF Research Database (Denmark)

    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...... for considering measures to reduce diffuse pollution of the aquatic environment....

  2. Rare earth elements in suspended and bottom sediments of the Mandovi estuary,central west coast of India: Influence of mining

    Digital Repository Service at National Institute of Oceanography (India)

    Shynu, R.; Rao, V.P.; Kessarkar, P.M.; Rao, T.G.

    Rare earth elements (REEs) in the suspended particulate matter (SPM) of the Mandovi estuary indicated that the mean total-REEs and light REE to heavy REE ratios are lower than that of the average suspended sediment in World Rivers and Post...

  3. Organic fuels for respiration in tropical river systems

    Science.gov (United States)

    Ward, N.; Keil, R. G.; Richey, J. E.; Krusche, A. V.; Medeiros, P. M.

    2011-12-01

    Watershed-derived organic matter is thought to provide anywhere from 30-90% of the organic matter in rivers (e.g. Hernes et al 2008; Spencer et al 2010). The most abundant biochemicals on land are cellulose, hemicelluloses, and lignin. Combined, they represent as much as 80% of the biomass in a typical forest and as much as 60% of the biomass in a typical field (natural or crop)(Bose et al 2009; Bridgeman et al., 2007; Hu and Zu 2006; Martens et al 2004). They are often assumed to be refractory and hard to degrade, but this assumption is at odds with virtually all observations: soils and marine sediments are not accumulating vast amounts of these compounds (Hedges and Oades, 1997), and degradation experiments suggest that cellulose, hemicelluloses and lignin are reactive and likely to be important fuels for respiration (Benner, 1991; Haddad et al, 1992; Dittmar et al, 2001; Otto and Simpson, 2006). During several trips to the lower Amazon River, incubation experiments were performed in which the biological degradation of lignin phenols was observed in order to assess the contribution of microbial respiration of terrestrially-derived macromolecules to gross respiration and CO2 gas evasion rates. Both particulate and dissolved lignin concentrations decreased by ~40% after being incubated in the dark for 5-7 days, indicating a turnover time of the entire lignin pool of 12-18 days. These results shift the paradigm that lignocellulose derived OM is highly recalcitrant, and indicate that microbial respiration of lignocellulose may play a larger role in total respiration rates/CO2 outgassing than previously thought. A simple mass balance calculation was done to test whether microbial degradation alone could explain the lignin data observed in the field. First, a theoretical particulate lignin concentration for Macapa was calculated based on the observed data at Obidos. The measured rate of particulate lignin degradation was multiplied by the transit time of water from

  4. NICKEL SPECIATION OF URBAN PARTICULATE MATTER

    Energy Technology Data Exchange (ETDEWEB)

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

    2003-10-01

    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.

  5. Suspended solids in liquid effluents

    International Nuclear Information System (INIS)

    McGrath, J.J.

    1988-06-01

    An international literature review and telephone mail survey was conducted with respect to technical and regulatory aspects of suspended solids in radioactive liquid wastes from nuclear power stations. Results of the survey are summarized and show that suspended solids are an important component of some waste streams. The data available, while limited, show these solids to be associated largely with corrosion products. The solids are highly variable in quantity, size and composition. Filtration is commonly applied for their removal from liquid effluents and is effective. Complex interactions with receiving waters can result in physical/chemical changes of released radionuclides and these phenomena have been seen as reason for not applying regulatory controls based on suspended solids content. 340 refs

  6. Mercury partition in the interface between a contaminated lagoon and the ocean: The role of particulate load and composition

    International Nuclear Information System (INIS)

    Pato, P.; Otero, M.; Valega, M.; Lopes, C.B.; Pereira, M.E.; Duarte, A.C.

    2010-01-01

    After having estimated the patterns of flow to the ocean and found some seasonal and tidal differences, mainly with regard to the relative importance of dissolved and particulate fractions, mercury partitioning at the interface between a contaminated lagoon and the Atlantic Ocean was investigated during four tidal cycles in contrasting season and tidal regimes. Mercury was found to be located predominantely in the particulate fraction throughout the year, contributing to its retention within the system. Seasonal conditions, variations in marine and fluvial signals and processes affecting bed sediment resuspension influenced the character and concentration of suspended particulate matter in the water column. Variation in the nature, levels and partitioning of organic carbon in the particulate fraction affected levels of particulate mercury as well as mercury partitioning. These results highlight the dominant role of suspended particulate matter in the distribution of anthropogenic mercury and reinforce the importance of competitive behavior related to organic carbon in mercury scavenging.

  7. Suspending Zeolite Particles In Tanks

    International Nuclear Information System (INIS)

    Poirier, M.R.

    1999-01-01

    The Savannah River Site (SRS) is in the process of removing waste (sludge and salt cake) from million gallon waste tanks. The current practice for removing waste from the tanks is adding water, agitating the tanks with long shaft vertical centrifugal pumps, and pumping the sludge/salt solution from the tank to downstream treatment processes. This practice has left sludge heels (tilde 30,000 gallons) in the bottom of the tanks. SRS is evaluating shrouded axial impeller mixers for removing the sludge heels in the waste tanks. The authors conducted a test program to determine mixer requirements for suspending sludge heels using the shrouded axial impeller mixers. The tests were performed with zeolite in scaled tanks which have diameters of 1.5, 6.0, and 18.75 feet. The mixer speeds required to suspend zeolite particles were measured at each scale. The data were analyzed with various scaling methods to compare their ability to describe the suspension of insoluble solids with the mixers and to apply the data to a full-scale waste tank. The impact of changes in particle properties and operating parameters was also evaluated. The conclusions of the work are: Scaling of the suspension of fast settling zeolite particles was best described by the constant power per unit volume method. Increasing the zeolite particle concentration increased the required mixer power needed to suspend the particles. Decreasing the zeolite particle size from 0.7 mm 0.3 mm decreased the required mixer power needed to suspend the particles. Increasing the number of mixers in the tank decreased the required mixer power needed to suspend the particles. A velocity of 1.6 ft/sec two inches above the tank bottom is needed to suspend zeolite particles

  8. Respiration in spiders (Araneae).

    Science.gov (United States)

    Schmitz, Anke

    2016-05-01

    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.

  9. State of the art in monitoring respirable mine aerosols

    Energy Technology Data Exchange (ETDEWEB)

    Volkwein, J.C.; Mischler, S.E.; Thimons, E.D.; Timko, R.J.; Kissell, F.N.

    2005-07-01

    The Centers for Disease Control and Prevention (CDC), National Institute for Occupational Safety and Health (NIOSH) has been developing several new tools to help miners monitor respirable coal dust, silica, and diesel particulate matter. This paper discusses three main topics. First, the latest results of the person wearable dust monitor (PDM), developed by Rupprecht and Patashnick under CDC contract. The PDM was tested side by side with conventional samplers at a number of US coal mines and results indicated that the PDM was comparable to conventional samplers. Second, improvements to the Dust Dosimeter monitoring technique that includes a new pump with built in pressure transducer and algorithm to convert differential pressure to dust concentration have shown good precision. Third, advances in the use of the detector tube technique to monitor tailpipe diesel emissions and ambient diesel particulate matter show that strong correlations exist between differential pressure measurement and elemental carbon in the samplers. 3 figs.

  10. Mitochondrial Respiration and Oxygen Tension.

    Science.gov (United States)

    Shaw, Daniel S; Meitha, Karlia; Considine, Michael J; Foyer, Christine H

    2017-01-01

    Measurements of respiration and oxygen tension in plant organs allow a precise understanding of mitochondrial capacity and function within the context of cellular oxygen metabolism. Here we describe methods that can be routinely used for the isolation of intact mitochondria, and the determination of respiratory electron transport, together with techniques for in vivo determination of oxygen tension and measurement of respiration by both CO 2 production and O 2 consumption that enables calculation of the respiratory quotient [CO 2 ]/[O 2 ].

  11. Respirable versus inhalable dust sampling

    International Nuclear Information System (INIS)

    Hondros, J.

    1987-01-01

    The ICRP uses a total inhalable dust figure as the basis of calculations on employee lung dose. This paper was written to look at one aspect of the Olympic Dam dust situation, namely, the inhalable versus respirable fraction of the dust cloud. The results of this study will determine whether it is possible to use respirable dust figures, as obtained during routine monitoring to help in the calculations of employee exposure to internal radioactive contaminants

  12. Interpreting, measuring, and modeling soil respiration

    Science.gov (United States)

    Michael G. Ryan; Beverly E. Law

    2005-01-01

    This paper reviews the role of soil respiration in determining ecosystem carbon balance, and the conceptual basis for measuring and modeling soil respiration. We developed it to provide background and context for this special issue on soil respiration and to synthesize the presentations and discussions at the workshop. Soil respiration is the largest component of...

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

    Science.gov (United States)

    Pandey, Palak; Kunte, Pravin D.

    2016-10-01

    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.

  14. Role of oxidative damage in toxicity of particulates

    DEFF Research Database (Denmark)

    Møller, Peter; Jacobsen, Nicklas R; Folkmann, Janne K

    2010-01-01

    composition play important roles in the oxidative potential of particulates. Studies in animal models indicate that particles from combustion processes (generated by combustion of wood or diesel oil), silicate, titanium dioxide and nanoparticles (C60 fullerenes and carbon nanotubes) produce elevated levels......Particulates are small particles of solid or liquid suspended in liquid or air. In vitro studies show that particles generate reactive oxygen species, deplete endogenous antioxidants, alter mitochondrial function and produce oxidative damage to lipids and DNA. Surface area, reactivity and chemical...

  15. A mechanical breathing simulator for respirator test

    International Nuclear Information System (INIS)

    Murata, Mikio; Ikezawa, Yoshio; Yoshida, Yoshikazu

    1976-01-01

    A mechanical breathing simulator has been developed to produce the human respiration for use in respirator test. The respirations were produced through the strokes of piston controlled by a rockerarm with adjustable fulcrum. The respiration rate was governed by motor-speed control, independent of the tidal volume achieved by adjustment of the piston stroke. By the breather, the simulated respirations for work rate 0, 208, 415, 622 and 830 kg-m/min could be produced through the typical dummy head. (auth.)

  16. Particulate and soluble 210Pd activities in the deep sea

    International Nuclear Information System (INIS)

    Somayajulu, B.L.K.; Craig, H.

    1976-01-01

    Particulate and soluble, 210 Pb activities have been measured by filtration of large-volume water samples at two stations in the South Atlantic. Particulate phase 210 Pb (caught by a 0.4-μm filter) varies from 0.3% of total 210 Pb in equatorial surface water to 15% in the bottom water. The 'absolute activity' of 210 Pb per unit mass of particulate matter is about 10 7 times the activity of soluble 210 Pb per unit mass of water, but because the mass ratio of particulate matter to water is about 10 -8 , the particulate phase carries only about 10% of the total activity. In Antarctic surface water the particulate phase carries 40% of the total 210 Pb activity; the absolute activity of this material is about the same as in other water masses and the higher fraction is due to the much larger concentration of suspended matter in surface water in this region. In the equatorial Atlantic the particulate phase 210 Pb activity increases with depth, by a factor of 40 from surface to bottom, and by a factor of 4 from the Antarctic Intermediate water core to the Antarctic Bottom Water. (Auth.)

  17. А mathematical model study of suspended monorail

    OpenAIRE

    Viktor GUTAREVYCH

    2012-01-01

    The mathematical model of suspended monorail track with allowance for elastic strain which occurs during movement of the monorail carriage was developed. Standard forms for single span and double span of suspended monorail sections were established.

  18. А mathematical model study of suspended monorail

    Directory of Open Access Journals (Sweden)

    Viktor GUTAREVYCH

    2012-01-01

    Full Text Available The mathematical model of suspended monorail track with allowance for elastic strain which occurs during movement of the monorail carriage was developed. Standard forms for single span and double span of suspended monorail sections were established.

  19. Suspended Solids Profiler Shop Test Report

    International Nuclear Information System (INIS)

    STAEHR, T.W.

    2000-01-01

    The Suspended Solids Profiler (SSP) Instrument is planned to be installed in the AZ-101 tank to measure suspended solids concentrations during mixer pump testing. The SSP sensor uses a reflectance measurement principle to determine the suspended solids concentrations. The purpose of this test is to provide a documented means of verifying that the functional components of the SSP operate properly

  20. Airborne particulate discriminator

    Science.gov (United States)

    Creek, Kathryn Louise [San Diego, CA; Castro, Alonso [Santa Fe, NM; Gray, Perry Clayton [Los Alamos, NM

    2009-08-11

    A method and apparatus for rapid and accurate detection and discrimination of biological, radiological, and chemical particles in air. A suspect aerosol of the target particulates is treated with a taggant aerosol of ultrafine particulates. Coagulation of the taggant and target particles causes a change in fluorescent properties of the cloud, providing an indication of the presence of the target.

  1. The investigation of atmospheric particulate matter pollution in Suzhou

    International Nuclear Information System (INIS)

    Chen Yi'ou; Zhang Yuliang; Wang Ya; Wang Pei; Tian Hailin

    2012-01-01

    Objective: To investigate the pollution status, vertical distribution and concentration variation within 24 hours of total suspended particles (TSPs), particulate matter ≤10 μm (PM10), particulate matter ≤5 (PM5) and particulate matter ≤2.5 μm (PM2.5) in major functional areas of Suzhou and the protective effect of different type masks on particulate matter. Methods: (1) The concentration of atmospheric TSPs, PM10, PM5 and PM2.5 in seven functional areas in Suzhou was monitored for three consecutive days. (2) A residential building of 25 stories was chosen and the concentration of TSPs, PM10, PM5, PM2.5 was detected at the 1st, 5th, 10th, 15th, 20 th and the 25th floor respectively. (3) The concentrations of the four particulate matter were detected every two-hours for three consecutive days to investigate how concentration of particulate matter varies within 24 hours. (4) The concentration of the four kinds of particulate matter was analyzed with the sampling head of monitor wrapped with disposable non-woven medical mask, fashion-type mask, gauze mask or activated carbon anti-dust mask respectively, and the protective effect of the four masks on particulate matter was compared. Results: (1) The concentration of PM2.5 was higher than the national health limit in all seven functional areas in Suzhou. (2) No significant difference in vertical distribution of particulate matter was found among different floors in residential buildings (P>0.05). (3) Two small peaks of particulate matter appeared in the morning and evening respectively while the top appeared at dawn (P< 0.05). (4) Disposable non-woven medical mask showed the best protective effect on particulate matter among the four tested masks. Conclusion: PM2.5 is the main particulate matter in Suzhou area. In addition the 4 kinds of particulate matter: TSP, PM10, PM5 and PM2.5 are of higher concentration in the early morning. No significant difference was detected from an altitude of less than 75 meters

  2. Subsurface migration of radioactive waste materials by particulate transport

    International Nuclear Information System (INIS)

    Eichholz, G.G.; Craft, T.F.; Powell, G.F.; Wahlig, B.G.

    1982-01-01

    The role of suspended particles as carriers of dissolved nuclides from high-level radioactive waste repositories has been investigated. Depending on the concentrations of suspended particles and the nature of the invading water, it has been found that cationic nuclides may be competitively adsorbed on suspended clay particles, the partitioning being largely determined by pH, temperature, and comparative surface areas of particulates and surrounding rocks. Column tests with activated particles have been conducted and showed that the clay particles pass readily through porous mineral columns and are increasingly retained if salinity is increased. Retention in basalt columns is stronger in the presence of high concentrations of sodium and calcium ions and has been explained in terms of van der Waals forces. The range of particulate migration then depends on the condition of the rock surfaces, the persistence of a clay coating, and the total dissolved ion concentration. For adsorbable waste ions, this may represent a pathway comparable in significance to ion-exchange-controlled migration. For some bed materials, the particulate movement displayed a prompt and a delayed component; the nature of the delay mechanism is not fully understood at present

  3. Facepiece leakage and fitting of respirators

    International Nuclear Information System (INIS)

    White, J.M.

    1978-05-01

    The ways in which airborne contaminants can penetrate respirators and the factors which affect the fit of respirators are discussed. The fit of the respirator to the face is shown to be the most critical factor affecting the protection achieved by the user. Qualitative and quantitative fit testing techniques are described and their application to industrial respirator programs is examined. Quantitative measurement of the leakage of a respirator while worn can be used to numerically indicate the protection achieved. These numbers, often referred to as protection factors, are sometimes used as the basis for selecting suitable respirators and this practice is reviewed. (author)

  4. General Instructions for Disposable Respirators

    Centers for Disease Control (CDC) Podcasts

    2009-04-09

    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.

  5. Use of Facemasks and Respirators

    Centers for Disease Control (CDC) Podcasts

    2007-05-15

    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.

  6. Characterization of particulate emissions from Australian open-cut coal mines: Toward improved emission estimates.

    Science.gov (United States)

    Richardson, Claire; Rutherford, Shannon; Agranovski, Igor

    2018-06-01

    Given the significance of mining as a source of particulates, accurate characterization of emissions is important for the development of appropriate emission estimation techniques for use in modeling predictions and to inform regulatory decisions. The currently available emission estimation methods for Australian open-cut coal mines relate primarily to total suspended particulates and PM 10 (particulate matter with an aerodynamic diameter available relating to the PM 2.5 (currently available emission estimation techniques, this paper presents results of sampling completed at three open-cut coal mines in Australia. The monitoring data demonstrate that the particulate size fraction varies for different mining activities, and that the region in which the mine is located influences the characteristics of the particulates emitted to the atmosphere. The proportion of fine particulates in the sample increased with distance from the source, with the coarse fraction being a more significant proportion of total suspended particulates close to the source of emissions. In terms of particulate composition, the results demonstrate that the particulate emissions are predominantly sourced from naturally occurring geological material, and coal comprises less than 13% of the overall emissions. The size fractionation exhibited by the sampling data sets is similar to that adopted in current Australian emission estimation methods but differs from the size fractionation presented in the U.S. Environmental Protection Agency methodology. Development of region-specific emission estimation techniques for PM 10 and PM 2.5 from open-cut coal mines is necessary to allow accurate prediction of particulate emissions to inform regulatory decisions and for use in modeling predictions. Development of region-specific emission estimation techniques for PM 10 and PM 2.5 from open-cut coal mines is necessary to allow accurate prediction of particulate emissions to inform regulatory decisions and for

  7. 78 FR 18535 - Respirator Certification Fees

    Science.gov (United States)

    2013-03-27

    ... facepiece respirators. The North American respiratory protection market generated revenues around $1,830 million in 2007, the most recent data available.\\4\\ A summary of market segmentation, by respirator type... management. Of the U.S. respirator market of products approved by NIOSH, approximately 35 percent of approval...

  8. Suspended dust in Norwegian cities

    International Nuclear Information System (INIS)

    2001-01-01

    According to calculations, at least 80 000 people in Oslo and 8 000 in Trondheim were annoyed by too much suspended dust in 2000. The dust concentration is greatest in the spring, presumably because dust is swirling up from melting snow and ice on the streets. Car traffic is the main source of the dust, except for some of the most highly exposed regions where wood-firing from old stoves contributes up to 70 percent of the dust. National targets for air quality include suspended dust, nitrogen dioxide, sulphur dioxide and benzene. Calculations show that nitrogen dioxide emissions exceeding the limit affected 4 000 people in Oslo and 1 000 people in Trondheim. The sulphur dioxide emissions in the major cities did non exceed the national quality limit; they did exceed the limit in some of the smaller industrial centres. In Trondheim, measurements show that the national limit for benzene was exceeded. Most of the emission of nitrogen dioxide comes from the road traffic. Local air pollution at times causes considerable health- and well-being problems in the larger cities and industrial centres, where a great part of the population may be at risk of early death, infection of the respiratory passage, heart- and lung diseases and cancer

  9. Contribution of Root Respiration to Soil Respiration in Sugarcane Plantation in Thailand

    OpenAIRE

    Wilaiwan Sornpoon; Sebastien Bonnet; Poonpipope Kasemsap; Savitri Garivait

    2013-01-01

    The understanding on the contribution of root respiration to total soil respiration is still very limited, especially for sugarcane. In this study, trenching experiments in sugarcane plantations were conducted to separate and investigate soil respiration for this crop. The measurements were performed for the whole growing period of 344 days to quantify root respiration. The obtained monitoring data showed that the respiration rate is increasing with the age of the plant, accounting for up to ...

  10. Effect of Feeding Schedule on Fractionated Particulate Matter Distribution in Rooster House

    Science.gov (United States)

    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...

  11. Elemental constituents of particulate matter and newborn’s size in eight European cohorts

    NARCIS (Netherlands)

    Pedersen, M.; Gehring, U.; Beelen, R.; Wang, M.; Giorgis-Allemand, L.; Andersen, A.M.N.; Basagaña, X.; Bernard, C.; Cirach, M.; Forastiere, F.; Hoogh, K. de; Gražuleviĉvienė, R.; Gruzieva, O.; Hoek, G.; Jedynska, A.; Klümper, C.; Kooter, I.M.; Krämer, U.; Kukkonen, J.; Porta, D.; Postma, D.S.; Raaschou-Nielsen, O.; Rossem, L. van; Sunyer, J.; Sørensen, M.; Tsai, M.Y.; Vrijkotte, T.G.M.; Wilhelm, M.; Nieuwenhuijsen, M.J.; Pershagen, G.; Brunekreef, B.; Kogevinas, M.; Slama, R.

    2016-01-01

    Background: The health effects of suspended particulate matter (PM) may depend on its chemical composition. Associations between maternal exposure to chemical constituents of PM and newborn’s size have been little examined. Objective: We aimed to investigate the associations of exposure to elemental

  12. Influence of particulate matter on microfouling biomass in the Arabian Sea

    Digital Repository Service at National Institute of Oceanography (India)

    Bhosle, N.B.; Nandakumar, K.; Wagh, A.B.

    ~ E :; :; 00 " " 200 '\\00 6001&. I&. Olslonc. from rne St>cre tn. miles! Leg , 0----4L~2 L~3 Leo .; Log $ Fig.3 Suspended matter (A), and particulate organic carbon (B) of surface seawater. and microfouling biomass as dry weight (C) and organic carbon...

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

    Science.gov (United States)

    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...

  14. Rapid monitoring particulate radiocesium with nonwoven fabric cartridge filter and application to field monitoring

    International Nuclear Information System (INIS)

    Tsuji, Hideki; Yasutaka, Tetsuo; Kondo, Yoshihiko; Kawashima, Shoji

    2013-01-01

    A method for rapid monitoring particulate radiocesium using a nonwoven fabric cartridge filter was developed, which needs no further preprocessing before served to a detector. By a performance test, more than 98% of suspended solid (SS) was collected. This method showed the same radioactivity measurement accuracy as filtration by membrane filter and more rapid extraction capability of SS. (author)

  15. Viscous bursting of suspended films

    Science.gov (United States)

    Debrégeas, G.; Martin, P.; Brochard-Wyart, F.

    1995-11-01

    Soap films break up by an inertial process. We present here the first observations on freely suspended films of long-chain polymers, where viscous effects are dominant and no surfactant is present. A hole is nucleated at time 0 and grows up to a radius R(t) at time t. A surprising feature is that the liquid from the hole is not collected into a rim (as it is in soap films): The liquid spreads out without any significant change of the film thickness. The radius R(t) grows exponentially with time, R~exp(t/τ) [while in soap films R(t) is linear]. The rise time τ~ηe/2γ where η is viscosity, e is thickness (in the micron range), and γ is surface tension. A simple model is developed to explain this growth law.

  16. Distribution of six radionuclides between soluble and particulate phase at the sea-freshwater interface

    International Nuclear Information System (INIS)

    Peres, J.M.

    1984-01-01

    The distribution of the soluble and particulate phases of radionuclides has been studied in water samples of various salinities (0 per mill; 3.8 per mill; 7.6 per mill; 15.2 per mill; 22.8 per mill; 30.4 per mill; 34 per mill). Cesium 137, cobalt 60, manganese 54, zinc 65, chromium 51 and sodium 22 were investigated. The results are expressed as retention percentages or distribution coefficients (Kd). Increased salinities resulted in decreased retention rates varying with the radionuclides; this appeared with the lowest salinities, and the evolution was small beyond 7 per mill. Other parameters were considered beside salinity, viz.: the suspended matter characteristics (mineralogy, particle size distribution); particulate load of water; organic content, whether associated to the soluble or particulate phase; physico-chemical forms of the radionuclides. To determine the particle size spectra of the suspended matter in the experimental samples, a laser granulometer was used [fr

  17. Identification and Characterization of Particulate Matter Concentrations at Construction Jobsites

    Directory of Open Access Journals (Sweden)

    Ingrid P. S. Araújo

    2014-11-01

    Full Text Available The identification and characterization of particulate matter (PM concentrations from construction site activities pose major challenges due to the diverse characteristics related to different aspects, such as concentration, particle size and particle composition. Moreover, the characterization of particulate matter is influenced by meteorological conditions, including temperature, humidity, rainfall and wind speed. This paper is part of a broader investigation that aims to develop a methodology for assessing the environmental impacts caused by the PM emissions that arise from construction activities. The objective of this paper is to identify and characterize the PM emissions on a construction site with different aerodynamic diameters (PM2.5, PM10, total suspended particulates (TSP, based on an exploratory study. Initially, a protocol was developed to standardize the construction site selection criteria, laboratory procedures, field sample collection and laboratory analysis. This protocol was applied on a multifamily residential building construction site during three different construction phases (earthworks, superstructure and finishings aimed at measuring and monitoring PM concentrations arising from construction activities. The particulate matter was characterized in different particle sizes. Results showed that the higher TSP emissions arising from construction activities provoked environmental impacts. Some limitations to the results were identified, especially with regards the need for a detailed investigation about the influence of different construction phases on PM emissions. The findings provided significant knowledge about various situations, serving as a basis for improving the existing methodology for particulate material collection on construction sites and the development of future studies on the specific construction site phases.

  18. Characterization of particulate amines

    International Nuclear Information System (INIS)

    Gundel, L.A.; Chang, S.G.; Clemenson, M.S.; Markowitz, S.S.; Novakov, T.

    1979-01-01

    The reduced nitrogen compounds associated with ambient particulate matter are chemically characterized by means of ESCA and proton activation analysis. Ambient particulate samples collected on silver filters in Berkeley, California were washed with water and organic solvents, and ESCA and proton activation analysis were performed in order to determine the composition of various nitrogen compounds and the total nitrogen content. It is found that 85% of the amines originally present in ambient particulate matter can be removed by water extraction, whereas the ammonium and nitrate are completely removed. An observed increase in ammonium ion in the extract, compared with its concentration in the original sample, coupled with the commensurate decrease in amine concentration, is attributed to the hydrolysis of amide groups, which may cause analytical methods based on extraction to yield erroneous results

  19. Intermodal resonance of vibrating suspended cables

    NARCIS (Netherlands)

    Rienstra, S.W.

    2010-01-01

    The weakly nonlinear free vibrations of a single suspended cable, or a coupled system of suspended cables, may be classified as gravity modes (no tension variations to leading order) and elasto-gravity modes (tension and vertical displacement equally important). It was found earlier [12] that the

  20. Microwave regenerated particulate trap

    Energy Technology Data Exchange (ETDEWEB)

    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)

    1997-12-31

    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.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1997-10-01

    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.

  2. Particulate air pollution and daily mortality in Detroit.

    Science.gov (United States)

    Schwartz, J

    1991-12-01

    Particulate air pollution has been associated with increased mortality during episodes of high pollution concentrations. The relationship at lower concentrations has been more controversial, as has the relative role of particles and sulfur dioxide. Replication has been difficult because suspended particle concentrations are usually measured only every sixth day in the U.S. This study used concurrent measurements of total suspended particulates (TSP) and airport visibility from every sixth day sampling for 10 years to fit a predictive model for TSP. Predicted daily TSP concentrations were then correlated with daily mortality counts in Poisson regression models controlling for season, weather, time trends, overdispersion, and serial correlation. A significant correlation (P less than 0.0001) was found between predicted TSP and daily mortality. This correlation was independent of sulfur dioxide, but not vice versa. The magnitude of the effect was very similar to results recently reported from Steubenville, Ohio (using actual TSP measurements), with each 100 micrograms/m3 increase in TSP resulting in a 6% increase in mortality. Graphical analysis indicated a dose-response relationship with no evidence of a threshold down to concentrations below half of the National Ambient Air Quality Standards for particulate matter.

  3. Management effects on European cropland respiration

    DEFF Research Database (Denmark)

    Eugster, Werner; Moffat, Antje M.; Ceschia, Eric

    2010-01-01

    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....... This allowed us to address the question of how management activities influence ecosystem respiration. This was done by comparing respiration fluxes during 7, 14, and 28 days after the management with those observed during the matching time period before management. Median increases in respiration ranged from...... 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 for a subset of 13...

  4. Effects of respirator use on worker performance

    Energy Technology Data Exchange (ETDEWEB)

    Cardarelli, R. [Yankee Atomic Electric Co., Bolton, MA (United States)

    1995-03-01

    In 1993, EPRI funded Yankee Atomic Electric Company to examine the effects of respirator use on worker efficiency. Phase I of Yankee`s effort was to develop a study design to determine respirator effects. Given success in Phase I, a larger population will be tested to determine if a stasitically significant respirator effect on performance can be measured. This paper summarizes the 1993 EPRI/Yankee Respirator Effects of Pilot Study, and describes the study design for the 1994 EPRI/Yankee Respirator Study to be conducted at the Oyster Creek Nuclear Power Plant. Also described is a summary of respirator effect studies that have been conducted during the last ten (10) years.

  5. Respirators: Supervisors Self-Study #43442

    Energy Technology Data Exchange (ETDEWEB)

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

    2016-04-20

    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).

  6. Cardiac, Skeletal, and smooth muscle mitochondrial respiration

    DEFF Research Database (Denmark)

    Park, Song-Young; Gifford, Jayson R; Andtbacka, Robert H I

    2014-01-01

    , 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), prespiration rates were normalized by CS (respiration...... per mitochondrial content), oxidative phosphorylation capacity was no longer different between the three muscle types. Interestingly, Complex I state 2 normalized for CS activity, an index of non-phosphorylating respiration per mitochondrial content, increased progressively from cardiac, skeletal...

  7. Characterization of airborne and bulk particulate from iron and steel manufacturing facilities.

    Science.gov (United States)

    Machemer, Steven D

    2004-01-15

    Characterization of airborne and bulk particulate material from iron and steel manufacturing facilities, commonly referred to as kish, indicated graphite flakes and graphite flakes associated with spherical iron oxide particles were unique particle characteristics useful in identifying particle emissions from iron and steel manufacturing. Characterization of airborne particulate material collected in receptor areas was consistent with multiple atmospheric release events of kish particles from the local iron and steel facilities into neighboring residential areas. Kish particles deposited in nearby residential areas included an abundance of graphite flakes, tens of micrometers to millimeters in size, and spherical iron oxide particles, submicrometer to tens of micrometers in size. Bulk kish from local iron and steel facilities contained an abundance of similar particles. Approximately 60% of blast furnace kish by volume consisted of spherical iron oxide particles in the respirable size range. Basic oxygen furnace kish contained percent levels of strongly alkaline components such as calcium hydroxide. In addition, concentrations of respirable Mn in airborne particulate in residential areas and at local iron and steel facilities were approximately 1.6 and 53 times the inhalation reference concentration of 0.05 microg/m3 for chronic inhalation exposure of Mn, respectively. Thus, airborne release of kish may pose potential respirable particulate, corrosive, or toxic hazards for human health and/or a corrosive hazard for property and the environment.

  8. A New Measure for Transported Suspended Sediment

    Science.gov (United States)

    Yang, Q.

    2017-12-01

    Non-uniform suspended sediment plays an important role in many geographical and biological processes. Despite extensive study, understanding to it seems to stagnate when times to consider non-uniformity and non-equilibrium scenarios comes. Due to unsatisfactory reproducibility, large-scaled flume seems to be incompetent to conduct more fundamental research in this area. To push the realm a step further, experiment to find how suspended sediment exchanges is conducted in a new validated equipment, in which turbulence is motivated by oscillating grids. Analysis shows that 1) suspended sediment exchange is constrained by ωS invariance, 2) ωS of the suspended sediment that certain flow regime could support is unique regardless of the sediment gradation and 3) the more turbulent the flow, the higher ωS of the suspension the flow could achieve. A new measure for suspended sediment ωS, the work required to sustain sediment in suspension transport mode if multiplied by gravitational acceleration, is thus proposed to better describe the dynamics of transported suspended sediment. Except for the further understanding towards suspended sediment transportation mechanics, with this energy measure, a strategy to distribute total transport capacity to different fractions could be derived and rational calculation of non-uniform sediment transport capacity under non-equilibrium conditions be possible.

  9. Organic compounds and suspended matter in the White Sea snow-ice cover

    International Nuclear Information System (INIS)

    Nemirovskaya, I.; Shevchenko, V.

    2008-01-01

    The pollution of the White Sea snow-ice cover was estimated by examining the distribution of organic compounds, including oil and pyrogenic hydrocarbons. Ice and snow cores were taken from Chupa Bay and the Kandalaksha Gulf in the Cape Kartesh area in the spring of 2004 and from the mouth of the Severnaya Dvina River in the spring of 2005, 2006, and 2007. This paper presented data on the lipid content, aliphatic hydrocarbons (AHC), polycyclic aromatic hydrocarbons (PAH) and suspended particulate matter in snow, ice and under-ice water. This paper focused on organic compounds and suspended matter (SM) concentrations in the sea snow-ice cover and described the ice forming conditions and interactions of the substances with ice, snow and sub-ice water. The amount of particulate matter and organic compounds in the snow increased sharply near industrial centres. The concentration of compounds decreased further away from these centres, suggesting that most pollutants are deposited locally. The study revealed that organic compounds concentrate in barrier zones, such as snow-ice and water-ice, depending on the source of pollution. There was no obvious evidence of petrogenic sources of PAHs in particulate matter from the White Sea snow-ice cover. The SM and organic compounds accumulated in layers characterized by local depositional processes. The zones remained biogeochemically active even under low temperature conditions, but the accumulation of both SM and organic compounds was at its highest during the initial stage of ice formation. 16 refs., 2 tabs., 4 figs

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

    Science.gov (United States)

    Lu, Xing-li; Liao, Yun-cheng

    2015-06-01

    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 soil respiration using exponential function equation. However, there was no significant correlation between soil respiration rate and soil moisture. Root respiration accounted for 45.13%-56.86% of the proportion of soil respiratio n with the mean value 51.72% during the summer corn growing season under different 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.

  11. High diversity of fungi in air particulate matter.

    Science.gov (United States)

    Fröhlich-Nowoisky, Janine; Pickersgill, Daniel A; Després, Viviane R; Pöschl, Ulrich

    2009-08-04

    Fungal spores can account for large proportions of air particulate matter, and they may potentially influence the hydrological cycle and climate as nuclei for water droplets and ice crystals in clouds, fog, and precipitation. Moreover, some fungi are major pathogens and allergens. The diversity of airborne fungi is, however, not well-known. By DNA analysis we found pronounced differences in the relative abundance and seasonal cycles of various groups of fungi in coarse and fine particulate matter, with more plant pathogens in the coarse fraction and more human pathogens and allergens in the respirable fine particle fraction (<3 microm). Moreover, the ratio of Basidiomycota to Ascomycota was found to be much higher than previously assumed, which might also apply to the biosphere.

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

    DEFF Research Database (Denmark)

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

    1999-01-01

    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....

  13. Year-round variations in the fluvial transport load of particulate 137Cs in a forested catchment affected by the Fukushima Daiichi Nuclear Power Plant accident

    International Nuclear Information System (INIS)

    Takeshi Matsunaga; Takahiro Nakanishi; Mariko Atarashi-Andoh; Erina Takeuchi; Kotomi Muto; Katsunori Tsuduki; Syusaku Nishimura; Jun Koarashi; Shigeyoshi Otosaka; Tsutomu Sato

    2016-01-01

    Particulate 137 Cs was collected from stream water for 2 years to assess the long-term trend of 137 Cs discharge from a forest after the Fukushima Nuclear Power Plant accident. A seasonal increase in the fluvial transport load of particulate 137 Cs in suspended solids (SS) was observed in July-October when rainfall was abundant. The 137 Cs load was controlled by the SS load. This control was attributed to cesium affinity for phyllosilicate clay minerals as verified by the low extractability of particulate 137 Cs. These findings indicate the fluvial particulate 137 Cs load is significantly related to the climate and geomorphological features of Japan. (author)

  14. Mitochondrial respiration is sensitive to cytoarchitectural breakdown.

    Science.gov (United States)

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

    2016-11-07

    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.

  15. Respirators: APR Issuer Self Study 33461

    Energy Technology Data Exchange (ETDEWEB)

    Chochoms, Michael [Los Alamos National Laboratory

    2016-07-13

    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

  16. Acute effects of total suspended particles and sulfur dioxides on preterm delivery: a community-based cohort study

    Energy Technology Data Exchange (ETDEWEB)

    Xu, X.P.; Ding, H.; Wang, X.B. [Harvard University, Boston, MA (United States). Dept. of Environmental Health

    1995-11-01

    The acute effects of air pollution on preterm delivery were examined in a prospective cohort in Beijing, China. From early pregnancy until delivery in 1988, we followed all registered pregnant women who lived in four residential areas of Beijing. Information for both mothers and infants was collected. Daily air pollution and meteorological data were obtained independently. The sample for analysis included 25 370 resident women who gave first live births in 1988. Multiple linear regression and logistic regression were used to estimate the effects of air pollution on gestational age and preterm delivery (i.e. {lt} 37 wk), with adjustment for outdoor temperature and humidity, day of the week, season, maternal age, gender of child, and residential area. Very high concentrations of ambient sulfur dioxide (mean = 102 {mu}g/m{sup 3}), (maximum = 630 {mu}g/m{sup 3}) and total suspended particulates (mean = 375 {mu}g/m{sup 3}), (maximum =1 003 {mu}g/m{sup 3}) were observed in these areas. There was a significant dose-dependent association between gestational age and sulfur dioxide and total suspended particulate concentrations. The estimated reduced duration of gestation was 0.075 wk (12.6 h) and 0.042 wk (7.1 h) for each 100 {mu}g/m{sup 3} increase in sulfur dioxide and total suspended particulates 7-d lagged moving average, respectively. We concluded that high levels of total suspended particulates and sulfur dioxide, or of a more complex pollution mixture associated with these pollutants, appear to contribute to excess risk of preterm delivery in this population. Further work needs to be carried out, with more detailed information on personal exposure and effect modifiers.

  17. [Absorption Characteristics of Particulates and CDOM in Waters of Chagan Lake and Xinlicheng Reservoir in Autumn].

    Science.gov (United States)

    Li, Si-jia; Song, Kai-shan; Zhao, Ying; Mu, Guang-yi; Shao, Tian-tian; Ma, Jian-hang

    2016-01-15

    Field surveys and laboratory analysis were carried out in Chagan Lake and Xinlicheng Reservoir under different salinity conditions in September 2012. In the laboratory, the absorption coefficients of particulates and chromophoric dissolved organic matter (CDOM) were measured, aiming to compare the absorption features, source of optical active substances and relative contribution of optical active constituents over the range of PAR (400-700 nm) in Chagan Lake and Xinlicheng Reservoir. The results showed that the Chagan Lake and Xinlicheng Reservoir were water bodies with medium eutrophication in autumn by TAL nutrient index and the absorption spectra of particulates matters were similar to those of phytoplankton. For the Chagan Lake with high salinity( EC = 988. 87 micro S x cm(-1)), the total particulate absorption was dominated by the nonalgal particles, and the contribution rate was in the order of nonalgal particles > phytoplankton > CDOM. For the Xinlicheng Reservoir with low salinity (EC = 311.67 microS x -cm(-1)), the total particulate absorption was dominated by the phytoplankton, and the contribution rate was ranked as phytoplankton > nonalgal particles > CDOM. Positive correlation was observed between a(p) (440), a(p) (675), a(d) (440) and total suspended matter (TSM), inorganic suspended matter (ISM), organic suspended matter (OSM) and Chl-a respectively in Chagan Lake, with correlation coefficients all above 0.55. Positive correlation was observed between a(p)(440), a(p) (675) and Chl-a (0.77 and 0.85, P CDOM in the Chagan Lake was less than that in the Xinlicheng Reservoir. The Chagan Lake was greatly affected by wind speed and shore collapse to produce suspended mineral and sediment particles. Thereby the total particulate absorption was dominated by the nonalgal particles. The waters in the Xinlicheng Reservoir were greatly impacted by terrestrial inorganic matter, and the growth of phytoplankton was weakened and microbes activities were strengthened

  18. Behavior of secondary particles in particulate matter collected at eastern Kanagawa

    International Nuclear Information System (INIS)

    Nishida, Tomohiro; Kikawada, Yoshikazu; Oi, Takao; Honda, Teruyuki

    2008-01-01

    The suspended particulate matters collected in 100 periods from 2002/10/28 to 2004/10/29 were separated into the water soluble and insoluble components and their main components were analyzed. The characteristics of atmosphere in the east part of Kagawa prefecture and of the secondary particulates were presumed. Therefore, it was considered that in the samples other than Mn the origins of water soluble and insoluble components are different each other from their behavior. The water-soluble part may be mostly ammonium salt (secondary particulate) from the measurement of NH 4 + . Furthermore, it became clear that the evolution of secondary particulate varies largely with season. Then, the variation with season was presumed by the main component analysis using the statistical software, SPSS adding to the correlation coefficient. This method has proved to be effective. (M.H.)

  19. Particulate carbon and nitrogen determinations in tracer studies: The neglected variables

    International Nuclear Information System (INIS)

    Collos, Yves; Jauzein, Cécile; Hatey, Elise

    2014-01-01

    We address two issues in the determination of particulate carbon and nitrogen in suspended matter of aquatic environments. One is the adsorption of dissolved organic matter on filters, leading to overestimate particulate matter. The second is the material loss during filtration due to fragile algal cells breaking up. Examples from both laboratory cultures and natural samples are presented. We recommend using stacked filters in order to estimate the first and filtering different volumes of water in order to evaluate the second. - Highlights: • Adsorption of dissolved organic matter on GF/F filters saturates below 1 ml. • Such adsorption can overestimate (up to 5 fold at low volumes) particulate matter. • Plankton breakage during filtration underestimates (up to 3 fold) particulate matter. • Different volumes should be filtered to detect biases in PC and PN concentrations. • Adsorbed organic carbon is higher in surface ocean than in mid-waters

  20. Organic and elemental carbon bound to particulate matter in the air of printing office and beauty salon

    Science.gov (United States)

    Rogula-Kopiec, Patrycja; Pastuszka, Józef S.; Rogula-Kozłowska, Wioletta; Mucha, Walter

    2017-11-01

    The aim of this study was to determine the role of internal sources of emissions on the concentrations of total suspended particulate matter (TSP) and its sub-fraction, so-called respirable PM (PM4; fraction of particles with particle size ≤ 4 µm) and to estimate to which extent those emissions participate in the formation of PM-bound elemental (EC) and organic (OC) carbon in two facilities - one beauty salon and one printing office located in Bytom (Upper Silesia, Poland). The average concentration of PM in the printing office and beauty salon during the 10-day measurement period was 10 and 4 (PM4) and 8 and 3 (TSP) times greater than the average concentration of PM fractions recorded in the same period in the atmospheric air; it was on average: 204 µg/m3 (PM4) and 319 µg/m3 (TSP) and 93 µg/m3 (PM4) and 136 µg/m3 (TSP), respectively. OC concentrations determined in the printing office were 38 µg/m3 (PM4) and 56 µg/m3 (TSP), and those referring to EC: 1.8 µg/m3 (PM4) and 3.5 µg/m3 (TSP). In the beauty salon the average concentration of OC for PM4 and TSP were 58 and 75 µg/m3, respectively and in case of EC - 3.1 and 4.7 µg/m3, respectively. The concentrations of OC and EC within the those facilities were approximately 1.7 (TSP-bound EC, beauty salon) to 4.7 (TSP-bound OC, printing office) times higher than the average atmospheric concentrations of those compounds measured in both PM fractions at the same time. In both facilities the main source of TSP-and PM4-bound OC in the indoor air were the chemicals - solvents, varnishes, paints, etc.

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

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-04-01

    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. Relationship between particle size and radiocesium in fluvial suspended sediment related to the Fukushima Daiichi Nuclear Power Plant accident

    International Nuclear Information System (INIS)

    Kazuya Tanaka

    2014-01-01

    We collected fluvial suspended sediments in Fukushima after the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident and analyzed the 137 Cs concentration in bulk and size-fractioned samples to investigate the particle-size-dependent distribution of radiocesium. The 137 Cs concentration in bulk suspended sediments decreased from August to December 2011, possibly reflecting a decrease of radiocesium concentration in its source materials. Smaller particles had higher radiocesium concentrations, reflecting larger specific surface areas. Silt- and sand-size fractions occupied more than 95 % of the total 137 Cs in the suspended sediments. The contribution of clay-size fractions, which had the highest 137 Cs concentration, was quite small because of their low frequency. A line of the data showed that the particle size distribution of radiocesium was essential to evaluate the migration and distribution of radiocesium in river systems where radiocesium is mainly present as particulate form after the FDNPP accident. (author)

  3. Characterization of the Particle Size Fraction associated with Heavy Metals in Suspended Sediments of the Yellow River

    Directory of Open Access Journals (Sweden)

    Qingzhen Yao

    2015-06-01

    Full Text Available Variations in the concentrations of particulate heavy metals and fluxes into the sea in the Yellow River were examined based on observational and measured data from January 2009 to December 2010. A custom-built water elutriation apparatus was used to separate suspended sediments into five size fractions. Clay and very fine silt is the dominant fraction in most of the suspended sediments, accounting for >40% of the samples. Cu, Pb, Zn, Cr, Fe and Mn are slightly affected by anthropogenic activities, while Cd is moderate affected. The concentrations of heavy metals increased with decrease in particle size. For suspended sediments in the Yellow River, on average 78%–82% of the total heavy metal loading accumulated in the <16 μm fraction. About 43% and 53% of heavy metal in 2009 and 2010 respectively, were readily transported to the Bohai Sea with “truly suspended” particles, which have potentially harmful effects on marine organisms.

  4. Estimation of suspended sediment concentration in rivers using acoustic methods.

    Science.gov (United States)

    Elçi, Sebnem; Aydin, Ramazan; Work, Paul A

    2009-12-01

    Acoustic Doppler current meters (ADV, ADCP, and ADP) are widely used in water systems to measure flow velocities and velocity profiles. Although these meters are designed for flow velocity measurements, they can also provide information defining the quantity of particulate matter in the water, after appropriate calibration. When an acoustic instrument is calibrated for a water system, no additional sensor is needed to measure suspended sediment concentration (SSC). This provides the simultaneous measurements of velocity and concentration required for most sediment transport studies. The performance of acoustic Doppler current meters for measuring SSC was investigated in different studies where signal-to-noise ratio (SNR) and suspended sediment concentration were related using different formulations. However, these studies were each limited to a single study site where neither the effect of particle size nor the effect of temperature was investigated. In this study, different parameters that affect the performance of an ADV for the prediction of SSC are investigated. In order to investigate the reliability of an ADV for SSC measurements in different environments, flow and SSC measurements were made in different streams located in the Aegean region of Turkey having different soil types. Soil samples were collected from all measuring stations and particle size analysis was conducted by mechanical means. Multivariate analysis was utilized to investigate the effect of soil type and water temperature on the measurements. Statistical analysis indicates that SNR readings ob tained from the ADV are affected by water temperature and particle size distribution of the soil, as expected, and a prediction model is presented relating SNR readings to SSC mea surements where both water temperature and sediment characteristics type are incorporated into the model. The coefficients of the suggested model were obtained using the multivariate anal ysis. Effect of high turbidity

  5. EVALUATION OF RETENTION POND AND CONSTRUCTED WETLAND BMPS FOR TREATING PARTICULATE-BOUND HEAVY METALS IN URBAN STORMWATER RUNOFF - 2007

    Science.gov (United States)

    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 ...

  6. Quantifying the environmental impact of particulate deposition from dry unpaved roadways

    Energy Technology Data Exchange (ETDEWEB)

    Becker, D.L.

    1979-01-01

    Airborne dust is the air pollutant most frequently observed to exceed National Ambient Air Quality Standards in rural areas. This pollutant (also referred to as suspended particulates) may originate from point sources (e.g., large areas of bare soil or pollen-producing vegetation.) Most sources of atmospheric particulates, whether natural or anthropogenic, are difficult to quantify by means of a source strength (i.e., mass of particulates emitted per unit time). A numerical model was developed for calculating the source strength and quantifying the atmospheric transport and eposition of dust generated on unpaved roadways. This model satisfies the second-order differential equation for the diffusion process and also the equation of mass conservation. Input to the model includes meterological variables, surface roughness characteristics, and the size distribution and suspended particulate concentration of dust as sampled downwind of an unpaved roadway. By using predetermined tolerance levels of airborne concentrations or tolerance levels of deposition, maximum allowable vehicular traffic volume can be established. The model also may be used to estimate reduction in photosynthesis resulting from fugitive dust from point or line sources. The contribug ion to sedimentation in aquatic bodies, resulting from airborne particulates also may be assessed with this model.

  7. Airborne particulate concentrations and fluxes at an active uranium mill tailings site

    International Nuclear Information System (INIS)

    Sehmel, G.A.

    1978-01-01

    Direct measurements of airborne particulate concentrations and fluxes of transported mill tailing materials were measured at an active mill tailings site. Experimental measurement equipment consisted of meteorological instrumentation to automatically activate total particulate air samplers as a function of wind speed increments and direction, as well as particle cascade impactors to measure airborne respirable concentrations as a function of particle size. In addition, an inertial impaction device measured nonrespirable fluxes of airborne particles. Caclulated results are presented in terms of the airborne solid concentration in g/m 3 , the horizontal airborne mass flux in g/(m 2 -day) for total collected nonrespirable particles and the radionuclide concentrations in dpm/g as a function of particle diameter for respirable and nonrespirable particles

  8. Evaluation of respirable particle matter in gold mine tailings on the Witwatersrand

    International Nuclear Information System (INIS)

    Ojelede, M.E.; Annegarn, H.J.

    2007-01-01

    Within the Witwatersrand gold mining area of South Africa, wind-blown dust is a significant contributor to atmospheric air pollution brought to the fore with the reworking of old mine tailings. Approximately 40,000 hectares are covered with tailings in the Witwatersrand. Wind-erosion during late austral winter and early spring causes surfaces of these tailings to be exposed, particularly during higher wind speeds and in the absence of rainfall. Local residents complain as the surrounding areas experience unpleasant dust episodes. As a result of urban PM 10 and PM 2.5 respirable particulate matter, increased respiratory ailments, morbidity and mortality, and concerns about the health impacts of wind-blown mine tailings in South Africa have been reported. Since 1981, significant monitoring of dustfall has taken place on the Witwatersrand, however, characterization of the respirable fraction of gold mine tailings material and dustfall is lacking. This paper presented the results of a study that established the content of respirable particulate matter in exposed mine tailings and wind-blown dust, and their likely contributions to ambient air. The initial results of the particulate size distribution of material samples from tailings and dust deposits collected in ambient dustfall-monitors were provided. Particle size distributions from different deposit types include slimes and sand deposits, surface and core material, and wind-winnowed secondary deposits. Fractions of PM 10 in source and deposited material were also discussed. It was concluded that there was a significant fraction of PM 10 material in the mine tailings, and that further work to quantify the population exposure risk is needed. 11 refs., 1 tab., 6 figs

  9. An index for estimating the potential metal pollution contribution to atmospheric particulate matter from road dust in Beijing.

    Science.gov (United States)

    Zhao, Hongtao; Shao, Yaping; Yin, Chengqing; Jiang, Yan; Li, Xuyong

    2016-04-15

    The resuspension of road dust from street surfaces could be a big contributor to atmospheric particulate pollution in the rapid urbanization context in the world. However, to date what its potential contribution to the spatial pattern is little known. Here we developed an innovative index model called the road dust index (RIatmospheric suspended particles. The factors were ranked and weighted based on road dust characteristics (the amounts, grain sizes, and mobilities of the road dust, and the concentrations and toxicities of metals in the road dust). We then applied the RIatmospheric suspended particles. The results demonstrated that the road dust in urban areas has higher potential risk of metal to atmospheric particles than that in rural areas. The RIatmospheric suspended particles and for controlling atmospheric particulate pollution caused by road dust emissions. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. BOREAS TE-5 Soil Respiration Data

    Science.gov (United States)

    Hall, Forrest G. (Editor); Curd, Shelaine (Editor); Ehleriinger, Jim; Brooks, J. Renee; Flanagan, Larry

    2000-01-01

    The BOREAS TE-5 team collected measurements in the NSA and SSA on gas exchange, gas composition, and tree growth. Soil respiration data were collected from 26-May-94 to 07-Sep-94 in the BOREAS NSA and SSA to compare the soil respiration rates in different forest sites using a LI-COR 6200 soil respiration chamber (model 6299). 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) Distrobuted Activity Archive Center (DAAC).

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

    Science.gov (United States)

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

    2017-10-01

    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, NH 4 Cl, 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 NH 4 Cl (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

  12. Transport of suspended matter through rock formations

    International Nuclear Information System (INIS)

    Wahlig, B.G.

    1980-01-01

    It may be hypothesized that significant quantities of some waste nuclides could be adsorbed on the surfaces of particles suspended in the flowing groundwater and thereby migrate farther or faster than they would in dissolved form. This thesis deals with one aspect of this proposed migration mechanism, the transport of suspended matter through rock formations. A theoretical examination of the forces effecting suspended particles in flowing groundwater indicates that only two interaction energies are likely to be significant compared to the particles' thermal energies. The responsible interactions are van der Waals attraction between the particles and the rock, and electrolytic double-layer repulsion between the atmospheres of ions near the surfaces of the particles and the rock. This theoretical understanding was tested in column flow adsorption experiments using fine kaolin particles as the suspended matter and crushed basalt as the rock medium. The effects of several parameters on kaolin mobility were explored, including the influences of the following: solution ion concentration, solution cation valence, degree of solution oxygen saturation, solution flow velocity, and degree of rock surface ageing. The experimental results indicate that the migration of suspended matter over kilometer distances in the lithosphere is very unlikely unless the average pore size of the conducting mediumis fairly large (> 1mm), or the flow occurs in large fractures

  13. Airborne Particulate Threat Assessment

    Energy Technology Data Exchange (ETDEWEB)

    Patrick Treado; Oksana Klueva; Jeffrey Beckstead

    2008-12-31

    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

  14. The particulate matter dispersion studies from a local palm oil mill

    International Nuclear Information System (INIS)

    Abdullah, L.C.; Wong, L. L.; Amnorzahira, A.; Sa'ari, M.; Abdul Rashid, M. S.; Salmiaton Ali

    2006-01-01

    The appearance of industrial emissions and the degradation of scenic vistas are two characteristics of air pollution that humans object. Reduction in visibility suggests worsening pollution levels. The emissions from mobile source and stationary source are the major source of air pollutions contribution in Malaysia. Suspended particulate matter (SPM). The consequence of increasing the particulate concentrations, the particulate matter dissolves with vapour and grows into droplets when the humidity exceeds approximately 70% and causing opaque situation know as haze. This work focuses on the dispersion particulate matter from palm oil mill. The data obtained serves the purpose of modeling the transport of particulate matter for obtaining permits and prevention of significant deterioration (PSD) to the environment. Gaussian Plume Model from a point source, subject to various atmospheric conditions is used to calculate particulate matter concentration then display the distribution of plume dispersion using geographic information system (GIS). The calculated particulate matter concentration is evaluated using Transilient Matrice function. Atmospheric Stability, mixing height, wind direction, wind speed, natural and artificial features play an important role in dispersion process. High concentration area exhibits immediately under prevailing wind direction. (Author)

  15. How much work is expended for respiration?

    Science.gov (United States)

    Johnson, A T

    1993-01-01

    The rate of work expended to move air in the respiratory system has been determined for five different airflow waveshapes, a non-linear respiratory model and five exercise levels. As expected, the rectangular waveshape was the most efficient. Model conditions were then changed one a time: (i) starting lung volume was allowed to vary, (ii) exhalation flow limitation was added, (iii) respiration was considered to be a metabolic burden determining part of the ventilation requirement and (iv) a respirator mask was added. Although there is no direct work advantage to varying initial lung volume, such volume changes appear to be dictated by the asymmetry of lung recoil pressure about the lung relaxation volume; allowing the work of respiration to become a metabolic burden clearly shows why respiratory waveforms change from rest to exercise; and, adding a respirator imposes a severe respiratory burden on the wearer engaging in moderate, heavy and very heavy exercise.

  16. [Real-time measurement of indoor particulate matter originating from environmental tobacco smoke: a pilot study].

    Science.gov (United States)

    Invernizzi, Giovanni; Ruprecht, Ario; Mazza, Roberto; Majno, Edoardo; Rossetti, Edoardo; Paredi, Paolo; Boffi, Roberto

    2002-01-01

    Short-term measurement of suspended particulate matter has been recently made possible since the release of laser-operating portable instruments. Data of a pilot study of field evaluation of environmental tobacco smoke (ETS) with a portable instrument are reported. We analysed the concentrations of total suspended particle (TSP) and of the fine particles PM10, PM7, PM2.5 and PM1 released indoor from a single cigarette, and their levels inside smoking- and non-smoking-areas of a restaurant. The results indicate that ETS creates high level indoor particulate pollution, with concentrations of PM10 exceeding air quality standards. This kind of field evaluation could allow a more careful assessing of short-term exposure to ETS and its relevance to public health.

  17. Elemental Spatiotemporal Variations of Total Suspended Particles in Jeddah City

    Directory of Open Access Journals (Sweden)

    Mohammad W. Kadi

    2014-01-01

    Full Text Available Elements associated with total suspended particulate matter (TSP in Jeddah city were determined. Using high-volume samplers, TSP samples were simultaneously collected over a one-year period from seven sampling sites. Samples were analyzed for Al, Ba, Ca, Cu, Mg, Fe, Mn, Zn, Ti, V, Cr, Co, Ni, As, and Sr. Results revealed great dependence of element contents on spatial and temporal variations. Two sites characterized by busy roads, workshops, heavy population, and heavy trucking have high levels of all measured elements. Concentrations of most elements at the two sites exhibit strong spatial gradients and concentrations of elements at these sites are higher than other locations. The highest concentrations of elements were observed during June–August because of dust storms, significant increase in energy consumption, and active surface winds. Enrichment factors of elements at the high-level sites have values in the range >10~60 while for Cu and Zn the enrichment factors are much higher (~0–>700 indicating that greater percentage of TSP composition for these three elements in air comes from anthropogenic activities.

  18. Separating rhizosphere respiration from total soil respiration in two larch plantations in northeastern China.

    Science.gov (United States)

    Jiang, Lifen; Shi, Fuchen; Li, Bo; Luo, Yiqi; Chen, Jiquan; Chen, Jiakuan

    2005-09-01

    The potential capacity of soil to sequester carbon in response to global warming is strongly regulated by the ratio of rhizosphere respiration to respiration by soil microbial decomposers, because of their different temperature sensitivities. To quantify relative contributions of rhizosphere respiration to total soil respiration as influenced by forest stand development, we conducted a trenching study in two larch (Larix gmelini (Rupr.) Rupr.) plantations, aged 17 and 31 years, in northeastern China. Four plots in each plantation were randomly selected and trenched in early May 2001. Soil surface CO2 effluxes both inside and outside the plots were measured from May 2001 to August 2002. Soil respiration (i.e., the CO2 effluxes outside the trenched plots) varied similarly in the two plantations from 0.8 micromol m(-2) s(-1) in winter to 6.0 micromol m(-2) s(-1) in summer. Rhizosphere respiration (i.e., CO2 efflux outside the trenched plots minus that inside the plots) varied from 0.2 to 2.0 micromol m(-2) s(-1) in the old forest and from 0.3 to 4.0 micromol m(-2) s(-1) in the young forest over the seasons. Rhizosphere respiration, on average, accounted for 25% of soil respiration in the old forest and 65% in the young forest. Rhizosphere and soil respiration were significantly correlated with soil temperature but not with soil water content. We conclude that the role forests play in regulating climate change may depend on their age.

  19. Gravimetric Measurements of Filtering Facepiece Respirators Challenged With Diesel Exhaust.

    Science.gov (United States)

    Satish, Swathi; Swanson, Jacob J; Xiao, Kai; Viner, Andrew S; Kittelson, David B; Pui, David Y H

    2017-07-01

    Elevated concentrations of diesel exhaust have been linked to adverse health effects. Filtering facepiece respirators (FFRs) are widely used as a form of respiratory protection against diesel particulate matter (DPM) in occupational settings. Previous results (Penconek A, Drążyk P, Moskal A. (2013) Penetration of diesel exhaust particles through commercially available dust half masks. Ann Occup Hyg; 57: 360-73.) have suggested that common FFRs are less efficient than would be expected for this purpose based on their certification approvals. The objective of this study was to measure the penetration of DPM through NIOSH-certified R95 and P95 electret respirators to verify this result. Gravimetric-based penetration measurements conducted using polytetrafluoroethylene (PTFE) and polypropylene (PP) filters were compared with penetration measurements made with a Scanning Mobility Particle Sizer (SMPS, TSI Inc.), which measures the particle size distribution. Gravimetric measurements using PP filters were variable compared to SMPS measurements and biased high due to adsorption of gas phase organic material. Relatively inert PTFE filters adsorbed less gas phase organic material resulting in measurements that were more accurate. To attempt to correct for artifacts associated with adsorption of gas phase organic material, primary and secondary filters were used in series upstream and downstream of the FFR. Correcting for adsorption by subtracting the secondary mass from the primary mass improved the result for both PTFE and PP filters but this correction is subject to 'equilibrium' conditions that depend on sampling time and the concentration of particles and gas phase hydrocarbons. Overall, the results demonstrate that the use of filters to determine filtration efficiency of FFRs challenged with diesel exhaust produces erroneous results due to the presence of gas phase hydrocarbons in diesel exhaust and the tendency of filters to adsorb organic material. Published by

  20. 42 CFR 84.134 - Respirator containers; minimum requirements.

    Science.gov (United States)

    2010-10-01

    ... 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 with a substantial, durable container bearing markings which show the applicant's name, the type and...

  1. 42 CFR 84.197 - Respirator containers; minimum requirements.

    Science.gov (United States)

    2010-10-01

    ... 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 with a substantial, durable container bearing markings which show the applicant's name, the type and...

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

    Digital Repository Service at National Institute of Oceanography (India)

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

    . Sheshshayee3 1Planetary and Geosciences Division, Physical Research Laboratory, Navrangpura, Ahmedabad- 380 009, India 2Chemical Oceanography Divivsion, National Institute of Oceanography, Dona Paula, Goa-403 004, India 3Department of Crop Physiology...) Whatman GF/F glass fibre filter (47 mm di- ameter, 0.7µm pore size). After the filtration the samples were dried at 60◦C and stored at room temperature for iso- topic analysis in the shore laboratory. Measurements of nitrogen isotope ratio and PON were car...

  3. Chemical partitioning of heavy metals in suspended particulates of Tajan River

    International Nuclear Information System (INIS)

    Nikoosepehr, E.

    2002-01-01

    In this investigation samples of river water sediments were collected at Takam bridge in Tajan River. In order to evaluate various chemical bonds ( loosely bonded ions, sulphides and organics), 120 A A S reading on Zn, Mn, Ni was carried out. The results indicates that Zn and Ni have more affinity towards sulphides while Cu and Mn are rather concentrated in loosely bonded ions. We have found out the following trends: Affinity of metals in loosely bonded ions in 63 and 40 μm fraction in Mn>Cu>Ni>Zn. Affinity of metals in organic bonds in 63 and 40 μm fraction is Zn>Ni>Mn>Cu and Zn>Ni>Cu>Mn respectively. It should be pointed out that metals do not show any regular pattern with sulphides: however in 63 μm fraction the trend is Zn>Ni>Cu>Mn

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

    Digital Repository Service at National Institute of Oceanography (India)

    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...

  5. Spectral signature of suspended fine particulate material on light absorption properties of CDOM

    DEFF Research Database (Denmark)

    Massicotte, Philippe; Stedmon, Colin; Markager, Stiig

    2017-01-01

    signature of the DOM pool and to quantify the effects of choice of filter type. In aquatic ecosystems influenced by terrestrial DOM (rivers and lakes), the dissolved fraction (here defined as... signature, particularly in situations where phytoplankton is the dominating source of DOM...

  6. 78 FR 40000 - Method for the Determination of Lead in Total Suspended Particulate Matter

    Science.gov (United States)

    2013-07-03

    ... is a government of a city, county, town, school district or special district with a population of... temperature of 80 [deg]C; VWR Model 750HT, 240W, or equivalent. Ultrasonic bath must meet the following..., SCP Science DigiPrep Model MS, No. 010-500-205 block digester capable of maintaining a temperature of...

  7. 78 FR 8066 - Method for the Determination of Lead in Total Suspended Particulate Matter

    Science.gov (United States)

    2013-02-05

    ... jurisdiction that is a government of a city, county, town, school district or special district with a... maintaining a temperature of 80[deg]C; VWR Model 750HT, 240W, or equivalent. Ultrasonic bath must meet the... temperature of 95[deg]C, or equivalent. 6.4 Materials and Supplies Argon gas supply, 99.99 percent purity or...

  8. Input of particulate organic and dissolved inorganic carbon from the Amazon to the Atlantic Ocean

    OpenAIRE

    Druffel, E. R. M; Bauer, J. E; Griffin, S.

    2005-01-01

    We report concentrations and isotope measurements (radiocarbon and stable carbon) of dissolved inorganic carbon (DIC) and suspended particulate organic carbon (POC) in waters collected from the mouth of the Amazon River and the North Brazil Current. Samples were collected in November 1991, when the Amazon hydrograph was at its annual minimum and the North Brazil Current had retroflected into the equatorial North Atlantic. The DIC Δ14C results revealed postbomb carbon in river and ocean waters...

  9. Respiration of Nitrate and Nitrite.

    Science.gov (United States)

    Cole, Jeffrey A; Richardson, David J

    2008-09-01

    Nitrate reduction to ammonia via nitrite occurs widely as an anabolic process through which bacteria, archaea, and plants can assimilate nitrate into cellular biomass. Escherichia coli and related enteric bacteria can couple the eight-electron reduction of nitrate to ammonium to growth by coupling the nitrate and nitrite reductases involved to energy-conserving respiratory electron transport systems. In global terms, the respiratory reduction of nitrate to ammonium dominates nitrate and nitrite reduction in many electron-rich environments such as anoxic marine sediments and sulfide-rich thermal vents, the human gastrointestinal tract, and the bodies of warm-blooded animals. This review reviews the regulation and enzymology of this process in E. coli and, where relevant detail is available, also in Salmonella and draws comparisons with and implications for the process in other bacteria where it is pertinent to do so. Fatty acids may be present in high levels in many of the natural environments of E. coli and Salmonella in which oxygen is limited but nitrate is available to support respiration. In E. coli, nitrate reduction in the periplasm involves the products of two seven-gene operons, napFDAGHBC, encoding the periplasmic nitrate reductase, and nrfABCDEFG, encoding the periplasmic nitrite reductase. No bacterium has yet been shown to couple a periplasmic nitrate reductase solely to the cytoplasmic nitrite reductase NirB. The cytoplasmic pathway for nitrate reduction to ammonia is restricted almost exclusively to a few groups of facultative anaerobic bacteria that encounter high concentrations of environmental nitrate.

  10. Distribution of some chemical elements between dissolved and particulate phases in the ocean. Research period: August 1, 1975--July 31, 1976

    International Nuclear Information System (INIS)

    1976-01-01

    Progress is reported on studies on the distributions of fallout 210 Pb and 210 Po in dissolved and particulate states in the Gulf of Maine and a transect of the equatorial North Atlantic Ocean. The ratio of 210 Pb/ 226 Ra and 210 Po/ 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

  11. Thoracic and respirable particle definitions for human health risk assessment.

    Science.gov (United States)

    Brown, James S; Gordon, Terry; Price, Owen; Asgharian, Bahman

    2013-04-10

    Particle size-selective sampling refers to the collection of particles of varying sizes that potentially reach and adversely affect specific regions of the respiratory tract. Thoracic and respirable fractions are defined as the fraction of inhaled particles capable of passing beyond the larynx and ciliated airways, respectively, during inhalation. In an attempt to afford greater protection to exposed individuals, current size-selective sampling criteria overestimate the population means of particle penetration into regions of the lower respiratory tract. The purpose of our analyses was to provide estimates of the thoracic and respirable fractions for adults and children during typical activities with both nasal and oral inhalation, that may be used in the design of experimental studies and interpretation of health effects evidence. We estimated the fraction of inhaled particles (0.5-20 μm aerodynamic diameter) penetrating beyond the larynx (based on experimental data) and ciliated airways (based on a mathematical model) for an adult male, adult female, and a 10 yr old child during typical daily activities and breathing patterns. Our estimates show less penetration of coarse particulate matter into the thoracic and gas exchange regions of the respiratory tract than current size-selective criteria. Of the parameters we evaluated, particle penetration into the lower respiratory tract was most dependent on route of breathing. For typical activity levels and breathing habits, we estimated a 50% cut-size for the thoracic fraction at an aerodynamic diameter of around 3 μm in adults and 5 μm in children, whereas current ambient and occupational criteria suggest a 50% cut-size of 10 μm. By design, current size-selective sample criteria overestimate the mass of particles generally expected to penetrate into the lower respiratory tract to provide protection for individuals who may breathe orally. We provide estimates of thoracic and respirable fractions for a variety of

  12. Soil Respiration And Respiration Partitioning In An Oak-Savannah With A History Of Fertilization

    Science.gov (United States)

    Morris, K. A.; Nair, R.; Schrumpf, M.; Migliavacca, M.

    2017-12-01

    Soil respiration is a combination of autotrophic and heterotrophic components. These components have different controls and structurally complex ecosystems such as oak-savannahs offer an opportunity to study strongly contrasting conditions (ie., soil from under trees versus open areas) in an environment with similar soil mineralogy and climatic patterns. To measure respiration coming from plant roots, fungal hyphae, and free-living microbes we established stations of soil cores comprised of three selectively permeable meshes under tree canopies and in open grassy areas of a Holm Oak (Quercus ilex) savannah in Extremadura, Spain. Large plots of this ecosystem had previously been fertilized as part of a stoichiometeric imbalance study (in 2015). Stations were installed in Dec. 2016 within four plots; control, N added, P added, and N+P added. Respiration from cores was measured in campaigns at key phenological stages with a portable Li-Cor 8100A unit. Six months after installation > 50% of soil respiration was attributable to free-living microbes. There is a persistent effect of the prior fertilization, resulting in increased soil respiration in open areas regardless of fertilizer type, while respiration from under tree canopies had a varied response. Soil under tree canopies showed distinct sensitivity to stoichiometric imbalance, meaning that addition of N or P alone either did not change respiration or decreased it slightly, while N+P stimulated respiration. We determined that respiration from free-living microbes is a major component of soil respiration even in the most active plant growing season. However, because of the lag between the time of fertilization and the time of measurement, it not possible to say whether treatment responses are due solely to nutrient status of the soil or whether changes in plant biomass and species composition also play a role. Additional work planned at the site will shed light on this uncertainty as well as the contribution of

  13. Determination of exposure to respirable quartz in the stone crushing units at Azendarian-West of Iran.

    Science.gov (United States)

    Bahrami, Abdul Rahman; Golbabai, Faridah; Mahjub, Hossien; Qorbani, Farshid; Aliabadi, Mohsan; Barqi, Mohamadali

    2008-08-01

    The purpose of this study is to describe the personal exposure to respirable dust and quartz and in stone crushing units located at west of Iran. A size of 40 personal samples and 40 stationary samples were obtained and analysis was done by X-ray diffraction (XRD). The results of personal sampling were shown the concentrations of respirable dust exposure level in workers of process, hopper and drivers were 1.90, 2.22, 1.41 times greater than Occupational Safety and Health Administration permissible exposure limit (OSHA PEL). The average value of total dust and respirable dust emission from stationary sources was 9.46 mg/m(3), 1.24 mg/m(3) respectively, showing that 13.8 % of total dust is respirable. The efficiency of local exhaust ventilation (LEV) to control of particles inside of industrial units was greater than 99%. It is concluded from this research the particulate generated from stone crushing activities contain a significant amount of respirable particle. The amount of free silica in stone quartz is 85 to 97 percent that emission of particles effect to health workers. LEV has important effect in the removal of silica particles in stone crushing units. The worker of hoppers still exposed to silica more than standard limits.

  14. [Research progress on photosynthesis regulating and controlling soil respiration].

    Science.gov (United States)

    Jing, Yan-Li; Guan, De-Xin; Wu, Jia-Bing; Wang, An-Zhi; Yuan, Feng-Hui

    2013-01-01

    To understand the mechanisms of soil respiration and accurately estimate its magnitude are the crucial basis of evaluating global carbon balance. However, the previously built soil respiration forecast models usually neglect the physiological processes that photosynthesis supplies substrates for rhizospheric respiration, leading to the defect in evaluating the mechanisms of soil respiration. This paper summarized the research progress on the mechanisms of photosynthetic regulation and control of soil respiration, introduced the related main research methods, and discussed the existing problems and research hotspots.

  15. Nuclear reactor with a suspended vessel

    International Nuclear Information System (INIS)

    Lemercier, Guy.

    1977-01-01

    This invention relates to a nuclear reactor with a suspended vessel and applies in particular when this is a fast reactor, the core or active part of the reactor being inside the vessel and immersed under a suitable volume of flowing liquid metal to cool it by extracting the calories released by the nuclear fission in the fuel assemblies forming this core [fr

  16. Bed-levelling experiments with suspended load

    NARCIS (Netherlands)

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

    1991-01-01

    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,

  17. The Shape of Breasts Suspended in Liquid

    NARCIS (Netherlands)

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

    2007-01-01

    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.

  18. (suspended solids and metals) removal efficiencies

    African Journals Online (AJOL)

    ABSTRACT. Presented in this paper are the results of correlational analyses and logistic regression between metal substances (Cd, Cu,. Pb, Zn), as well as suspended solids removal, and physical pond parameters of 19 stormwater retention pond case studies obtained from the International Stormwater BMP database.

  19. Plant Respiration and Climate Change Effects

    International Nuclear Information System (INIS)

    Bruhn, D.

    2002-04-01

    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 2 on plant respiration were investigated in a number of plant species. The experiments tested effects of either temperature and/or CO 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 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 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 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 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 2 release. (au)

  20. Plant Respiration and Climate Change Effects

    Energy Technology Data Exchange (ETDEWEB)

    Bruhn, D

    2002-04-01

    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)

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

    Energy Technology Data Exchange (ETDEWEB)

    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)

    2015-09-15

    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.)

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

    Science.gov (United States)

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

    2018-01-15

    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.

  3. Bulk metal concentrations versus total suspended solids in rivers: Time-invariant & catchment-specific relationships.

    Science.gov (United States)

    Nasrabadi, Touraj; Ruegner, Hermann; Schwientek, Marc; Bennett, Jeremy; Fazel Valipour, Shahin; Grathwohl, Peter

    2018-01-01

    Suspended particles in rivers can act as carriers of potentially bioavailable metal species and are thus an emerging area of interest in river system monitoring. The delineation of bulk metals concentrations in river water into dissolved and particulate components is also important for risk assessment. Linear relationships between bulk metal concentrations in water (CW,tot) and total suspended solids (TSS) in water can be used to easily evaluate dissolved (CW, intercept) and particle-bound metal fluxes (CSUS, slope) in streams (CW,tot = CW + CSUS TSS). In this study, we apply this principle to catchments in Iran (Haraz) and Germany (Ammer, Goldersbach, and Steinlach) that show differences in geology, geochemistry, land use and hydrological characteristics. For each catchment, particle-bound and dissolved concentrations for a suite of metals in water were calculated based on linear regressions of total suspended solids and total metal concentrations. Results were replicable across sampling campaigns in different years and seasons (between 2013 and 2016) and could be reproduced in a laboratory sedimentation experiment. CSUS values generally showed little variability in different catchments and agree well with soil background values for some metals (e.g. lead and nickel) while other metals (e.g. copper) indicate anthropogenic influences. CW was elevated in the Haraz (Iran) catchment, indicating higher bioavailability and potential human and ecological health concerns (where higher values of CSUS/CW are considered as a risk indicator).

  4. Improving respiration measurements with gas exchange analyzers.

    Science.gov (United States)

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

    2016-12-01

    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). CO 2 differential (ΔCO 2 ) increased two-fold with no change in apparent R d , when the two leaves with higher stomatal density faced outside. These results showed a clear effect of the position of stomata on ΔCO 2 . Therefore, it can be concluded that leaf position is important to guarantee the improvement of respiration measurements increasing ΔCO 2 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.

  5. Simplified pressure method for respirator fit testing.

    Science.gov (United States)

    Han, D; Xu, M; Foo, S; Pilacinski, W; Willeke, K

    1991-08-01

    A simplified pressure method has been developed for fit testing air-purifying respirators. In this method, the air-purifying cartridges are replaced by a pressure-sensing attachment and a valve. While wearers hold their breath, a small pump extracts air from the respirator cavity until a steady-state pressure is reached in 1 to 2 sec. The flow rate through the face seal leak is a unique function of this pressure, which is determined once for all respirators, regardless of the respirator's cavity volume or deformation because of pliability. The contaminant concentration inside the respirator depends on the degree of dilution by the flow through the cartridges. The cartridge flow varies among different brands and is measured once for each brand. The ratio of cartridge to leakflow is a measure of fit. This flow ratio has been measured on human subjects and has been compared to fit factors determined on the same subjects by means of photometric and particle count tests. The aerosol tests gave higher values of fit.

  6. Phenomenology and modeling of particulate corrosion product behavior in Hanford N Reactor primary coolant

    International Nuclear Information System (INIS)

    Bechtold, D.B.

    1983-01-01

    The levels and composition of filterable corrosion products in the Hanford N Reactor Primary Loop are measurable by filtration. The suspended crud level has ranged from 0.0005 ppM to 6.482 ppM with a median 0.050 ppM. The composition approximates magnetite. The particle size distribution has been found in 31 cases to be uniformly a log normal distribution with a count median ranging from 1.10 to 2.31 microns with a median of 1.81 microns, and the geometric standard deviation ranging from 1.60 to 2.34 with a median of 1.84. An auto-correcting inline turbidimeter was found to respond to linearly to suspended crud levels over a range 0.05 to at least 6.5 ppM by direct comparison with filter sample weights. Cause of crud bursts in the primary loop were found to be power decreases. The crud transients associated with a reactor power drop, several reactor shutdowns, and several reactor startups could be modeled consistently with each other using a simple stirred-tank, first order exchange model of particulate between makeup, coolant, letdown, and loosely adherent crud on pipe walls. Over 3/10 of the average steady running particulate crud level could be accounted for by magnetically filterable particulate in the makeup feed. A simulation model of particulate transport has been coded in FORTRAN

  7. The separation of particulate within PFC decontamination wastewater generated by PFC decontamination

    International Nuclear Information System (INIS)

    Kim, Gye Nam; Lee, Sung Yeol; Won, Hui Jun; Jung, Chong Hun; Oh, Won Zin; Park, Jin Ho; Narayan, M.

    2005-01-01

    When PFC(Perfluoro carbonate) decontamination technology is applied to removal of radioactive contaminated particulate adhered at surface during the operation of nuclear research facilities, it is necessary to develop a filtration equipment to reuse of PFC solution due to high price, also to minimize the volume of second wastewater. Contaminated characteristics of hot particulate was investigated and a filtration process was presented to remove suspended radioactive particulate from PFC decontamination wastewater generated on PFC decontamination. The range of size of hot particulate adhered at the surface of research facilities measured by SEM was 0.1∼10μm. Hot particulate of more than 2μm in PFC contamination wastewater was removed by first filter and then hot particulate of more than 0.2μm was removed by second filter. Results of filter experiments showed that filtration efficiency of PVDF(Poly vinylidene fluoride), PP(Polypropylene), Ceramic filter was 95∼97%. A ceramic filter showed a higher filtration efficiency with a little low permeate volume. Also, a ceramic of inorganic compound could be broken easily on experiment and has a high price but was highly stable at radioactivity in comparison of PVDF and PP of a macromolecule which generate H 2 gas in alpha radioactivity environment

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2010-06-22

    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.

  9. ADVANCED HYBRID PARTICULATE COLLECTOR

    Energy Technology Data Exchange (ETDEWEB)

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

    2001-12-01

    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

  10. The suspended sentence in French Criminal Law

    Directory of Open Access Journals (Sweden)

    Jovašević Dragan

    2016-01-01

    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

  11. Respirator Filter Efficiency Testing Against Particulate and Biological Aerosols Under Moderate to High Flow Rates

    Science.gov (United States)

    2006-08-01

    flow rate through the test filter. The flow rate was measured using a mass flow meter (Series 4000, TSI, Shoreview, MN). Several modifications were made...operating conditions. This included assessing the effect of non- isokinetic sampling, flow calibrations, and characterization of the challenge...sampling bias on the measured penetrations due to the non- isokinetic sampling downstream. 3.3.2.2 System Characterization. Shakedown tests were

  12. The external respiration and gas exchange in space missions

    Science.gov (United States)

    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.

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

    Science.gov (United States)

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

    2016-04-01

    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

  14. Abnormal mitochondrial respiration in failed human myocardium.

    Science.gov (United States)

    Sharov, V G; Todor, A V; Silverman, N; Goldstein, S; Sabbah, H N

    2000-12-01

    Chronic heart failure (HF) is associated with morphologic abnormalities of cardiac mitochondria including hyperplasia, reduced organelle size and compromised structural integrity. In this study, we examined whether functional abnormalities of mitochondrial respiration are also present in myocardium of patients with advanced HF. Mitochondrial respiration was examined using a Clark electrode in an oxygraph cell containing saponin-skinned muscle bundles obtained from myocardium of failed explanted human hearts due to ischemic (ICM, n=9) or idiopathic dilated (IDC, n=9) cardiomyopathy. Myocardial specimens from five normal donor hearts served as controls (CON). Basal respiratory rate, respiratory rate after addition of the substrates glutamate and malate (V(SUB)), state 3 respiration (after addition of ADP, V(ADP)) and respiration after the addition of atractyloside (V(AT)) were measured in scar-free muscle bundles obtained from the subendocardial (ENDO) and subepicardial (EPI) thirds of the left ventricular (LV) free wall, interventricular septum and right ventricular (RV) free wall. There were no differences in basal and substrate-supported respiration between CON and HF regardless of etiology. V(ADP)was significantly depressed both in ICM and IDC compared to CON in all the regions studied. The respiratory control ratio, V(ADP)/V(AT), was also significantly decreased in HF compared to CON. In both ICM and IDC, V(ADP)was significantly lower in ENDO compared to EPI. The results indicate that mitochondrial respiration is abnormal in the failing human heart. The findings support the concept of low myocardial energy production in HF via oxidative phosphorylation, an abnormality with a potentially impact on global cardiac performance. Copyright 2000 Academic Press.

  15. Electrically heated particulate filter restart strategy

    Science.gov (United States)

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

    2011-07-12

    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. Swing damped movement of suspended objects

    International Nuclear Information System (INIS)

    Jones, J.F.; Petterson, B.J.; Werner, J.C.

    1990-01-01

    Transportation of large objects such as nuclear waste shipping casks using overhead cranes can induce pendular motion of the object. Residual oscillation from transportation typically must be damped or allowed to decay before the next process can take place. By properly programming the acceleration of the transporting device (e.g., crane) an oscillation damped transport and swing free stop are obtainable. This report reviews the theory associated with formulating such oscillation damped trajectories for a simply suspended object (e.g., simple pendulum). In addition, the use of force servo damping to eliminate initial oscillation of simply suspended objects is discussed. This is often needed to provide a well defined initial state for the system prior to executing an oscillation damped move. Also included are descriptions of experiments using a CIMCORP XR6100 gantry robot and results from these experiments. Finally, sources of error resulting in small residual oscillations are identified and possible solutions presented

  17. Molybdenum-rhenium superconducting suspended nanostructures

    Energy Technology Data Exchange (ETDEWEB)

    Aziz, Mohsin; Christopher Hudson, David; Russo, Saverio [Centre for Graphene Science, College of Engineering, Mathematics and Physical Sciences, University of Exeter, Exeter EX4 4QF (United Kingdom)

    2014-06-09

    Suspended superconducting nanostructures of MoRe 50%/50% by weight are fabricated employing commonly used fabrication steps in micro- and nano-meter scale devices followed by wet-etching with Hydro-fluoric acid of a SiO{sub 2} sacrificial layer. Suspended superconducting channels as narrow as 50 nm and length 3 μm have a critical temperature of ≈6.5 K, which can increase by 0.5 K upon annealing at 400 °C. A detailed study of the dependence of the superconducting critical current and critical temperature upon annealing and in devices with different channel widths reveals that desorption of contaminants is responsible for the improved superconducting properties. These findings pave the way for the development of superconducting electromechanical devices using standard fabrication techniques.

  18. Electrodialytic remediation of suspended mine tailings

    DEFF Research Database (Denmark)

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

    2008-01-01

    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...... efficiency from 1% to 80% compared to experiments with no stirring but with the same operational conditions. This showed the crucial importance of having the solids in suspension and not settled during the remediation....

  19. Sedimentation of suspended solids in ultrasound field

    Directory of Open Access Journals (Sweden)

    Vikulina Vera

    2018-01-01

    Full Text Available Physical and chemical effects of aquatic environment that occur in an ultrasonic field change the sedimentation rate of coagulated suspension. This might only happen in case of cavitation of ultrasonic filed that causes a change of potentials of the medium. Research of the influence of ultrasonic vibrations on coagulation of suspended solids within water purification allows expanding their scope of implementation. The objective of the research is to estimate the effect of ultrasound on the sedimentation of the suspended solids, to determine of the efficiency of the process in relation to the dose of the coagulant, and to calculate the numerical values of the constants in the theoretical equation. The experiment condition was held in the water with the clay substances before the introduction of the coagulant. The method of magnetostriction ultrasonic generator was applied to receive ultrasonic vibration. Estimate of concentration of clay particles in water was performed using photometry. As a result of the research, the obtained data allow determining the increase in efficiency of suspended particles sedimentation related to the dose of coagulant, depending on time of ultrasonic treatment. The experiments confirmed the connection between the effect of sedimentation in the coagulation process, the coagulant dose and the time of scoring. Studies have shown that the increase in the duration of ultrasonic treatment causes a decrease of administered doses of coagulant.

  20. Influence of particulates on phosphorus loading exported from farm drainage during a storm event in the Everglades Agricultural Area

    Science.gov (United States)

    Bhadha, J. H.; Lang, T. A.; Daroub, S. H.

    2015-12-01

    The purpose of this study was to evaluate the influence of particulates on P loading captured during a single storm event. The Everglades Agricultural Area of Florida comprises 280,000 hectares of organic soil farmland artificially drained by ditches, canals and pumps. Phosphorus (P)-enriched suspended particulates in canals are susceptible to transport and can contribute significantly to the overall P loads in drainage water. A settling tank experiment was conducted to capture particulates during tropical storm Isaac in 2012 from three farms approximately 2.4 to 3.6 km2 in size. Farm canal discharge water was collected in a series of two 200 liter settling tanks over a seven-day drainage period, during tropical storm Isaac. Water from the settling tanks was siphoned through Imhoff settling cones, where the particulates were allowed to settle and collected for P-fractionation analyses, and compared to intact sediment cores collected from the bottom of the canals. The discharged particulates contained higher organic matter content (OM), total P, and labile P fractions compared to the canal bottom sediments. Based on the equilibrium P concentrations, surface sediments behave as a source of P to the water column. A seven-day continuous drainage event exported 4.7 to 11.1 metric tons of suspended solids per farm, corresponding to 32 to 63 kg of particulate P being lost to downstream ecosystems. Drainage associated to a single seven-day storm event exported up to 61% of the total annual farm P load. It is evident from this study that short-term, high-intensity storm events can skew annual P loads due to the export of significantly higher particulate matter from farm canals. Exported particulates rich in P can provide a supplemental source of nutrients if captured and replenished back into the farmlands, as a sustainable farming practice.

  1. Electrical diesel particulate filter (DPF) regeneration

    Science.gov (United States)

    Gonze, Eugene V; Ament, Frank

    2013-12-31

    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.

  2. Transport of free and particulate-associated bacteria in karst

    Science.gov (United States)

    Mahler, B. J.; Personné, J.-C.; Lods, G. F.; Drogue, C.

    2000-12-01

    Karst aquifers, because of their unique hydrogeologic characteristics, are extremely susceptible to contamination by pathogens. Here we present the results of an investigation of contamination of a karst aquifer by fecal indicator bacteria. Two wells intercepting zones with contrasting effective hydraulic conductivities, as determined by pump test, were monitored both during the dry season and in response to a rain event. Samples were also collected from the adjacent ephemeral surface stream, which is known to be impacted by an upstream wastewater treatment plant after rainfall. Whole water and suspended sediment samples were analyzed for fecal coliforms and enterococci. During the dry season, pumping over a 2-day period resulted in increases in concentrations of fecal coliforms to greater than 10,000 CFU/100 ml in the high-conductivity well; enterococci and total suspended solids also increased, to a lesser degree. Toward the end of the pumping period, as much as 50% of the fecal coliforms were associated with suspended sediment. Irrigation of an up-gradient pine plantation with primary-treated wastewater is the probable source of the bacterial contamination. Sampling after a rain event revealed the strong influence of water quality of the adjacent Terrieu Creek on the ground water. Bacterial concentrations in the wells showed a rapid response to increased concentrations in the surface water, with fecal coliform concentrations in ground water ultimately reaching 60,000 CFU/100 ml. Up to 100% of the bacteria in the ground water was associated with suspended sediment at various times. The results of this investigation are evidence of the strong influence of surface water on ground water in karst terrain, including that of irrigation water. The large proportion of bacteria associated with particulates in the ground water has important implications for public health, as bacteria associated with particulates may be more persistent and more difficult to inactivate. The

  3. The suspended sentence in German criminal law

    Directory of Open Access Journals (Sweden)

    Jovašević Dragan

    2017-01-01

    Full Text Available From the ancient times until today, criminal law in all countries has provided different criminal sanctions as social control measures. These are court-imposed coercive measures that take away or limit certain rights and freedoms of criminal offenders. Sanctions are applied to natural or legal persons who violate the norms of the legal order and cause damage or endanger other legal goods that enjoy legal protection. In order to effectively protect social values jeopardized by the commission of crime, state legislations prescribe several kinds of criminal sanctions: 1 penalties, 2 precautions, 3 safety measures, 4 penalties for juvenile offenders, and 5 sanctions for legal persons. Penalties are the basic, the oldest and the most important type of criminal sanctions. They are prescribed for the largest number of criminal offences. Imposed instead of or alongside with penalties, warning measures have particularly important role in jurisprudence. Since they were introduced in the system of criminal sanctions in the early 20th century, there has been a notable increase in the application of these measures, particularly in cases involving negligent and accidental offences, and minor offences that do not cause serious consequences, whose perpetrators are not persons with criminal characteristics. Warning measures (suspended sentence are envisaged in all contemporary criminal legislations, including the German legislation. Suspended sentence is a conditional stay of execution of the sentence of imprisonment for a specified time, provided that the convicted person fulfills the imposed obligations and does not commit another criminal offense. Two conditions must be fulfilled for the application of these sanctions: a the formal requirement, which is attached to the sentence of imprisonment; and b the substantive requirement, which implies the court assessment that the application of these sanctions is justified and necessary in a particular case. Many

  4. Sulfide-inhibition of mitochondrial respiration at very low oxygen concentrations.

    Science.gov (United States)

    Matallo, J; Vogt, J; McCook, O; Wachter, U; Tillmans, F; Groeger, M; Szabo, C; Georgieff, M; Radermacher, P; Calzia, E

    2014-09-15

    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

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

    Directory of Open Access Journals (Sweden)

    Ben J. Williamson

    2003-04-01

    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.

  6. Directly transport of suspended matter from the Yangtze River to the Okinawa trough post-major flood '98: evidence from stable isotopes and C/N ratios

    International Nuclear Information System (INIS)

    Cai Deling; Shi Xuefa; Song Xiaohong

    2007-01-01

    Water column concentrations of total suspended matter (TSM), particulate organic carbon (POC), particulate nitrogen (PN) and their stable isotopic compositions (δ 13 C and δ 15 N) are measured at two to five different depths in the Yellow Sea and East China Seas and Yangtze Estuary to clarify the effect of '98 Yangtze great flood on the transport of suspended matter in the Yellow Sea and East China Sea. Suspended matters are collected to analyze the distributions of TSM, POC, PN and salinity throughout the Yellow Sea and East China Sea in the autumn of 1998. There are marked positive correlations (r=0.89-0.98) among TSM, POC and PN, but negative relationships (r=-0.29 - -0.59) between TSM and salinity. These results conclude that the POC and PN were controlled primarily by the concentrations of TSM. The C/N ratios of particulate organic matter have a negative linear correlation with PN% (r=-0.44 - -0.71), but no correlation with POC%, which suggests C/N ratios are mainly controlled by PN%. There are distinct positive correlations between δ 15 N and POC% or PN% in surface water (r=0.36 and 0.24, p<0.01, respectively), however, the correlation do not exist in more deeper depths. In indicates that δ 15 N PN could be changed by a lot of factors, such as nutrient availability, nitrification, denitrification, different material sources and so on, except decomposition of organic matter. The distributions of C/N ratios and δ 13 C values of the particulate organic matter suggest that suspended matters from Yangtze River could be transported directly into the Okinawa Trough under the condition of '98 Yangtze major flood, which break through the foregone knowledge obtained under the normal hydrological condition. (authors)

  7. Particulate Matter Resuspension in Mississippi Bight Evaluated with CONCORDE's Synthesis Model

    Science.gov (United States)

    O'Brien, S. J.; Quas, L. M.; Miles, T. N.; Pan, C.; Cambazoglu, M. K.; Soto Ramos, I. M.; Greer, A. T.; Church, I.; Wiggert, J. D.

    2017-12-01

    The CONsortium for oil spill exposure pathways in COastal River-Dominated Ecosystems (CONCORDE) was established to investigate the complex fine-scale biological, chemical and physical interactions in a marine system controlled by pulsed-river plume dynamics. During CONCORDE's spring 2016 field campaign, the In Situ Ichthyoplankton Imaging System (ISIIS) on the R/V Point Sur and the Scanfish on the R/V Pelican comprehensively characterized the physical and biological structure in the region. Increased suspended particulate matter was observed by the ISIIS, with concentrations at depth sufficient to completely occlude the in situ images of planktonic organisms. Data was also collected on the continental shelf during the spring cruise by the RU31 glider in the proximity of the Mississippi River Delta, east of the ISIIS / Scanfish transects. Backscatter and salinity observed by the Scanfish and glider showed elevated suspended particulate matter and increased salinity, suggesting a linkage to shoreward advection from the continental shelf of oceanic waters that are sufficiently energetic to drive sediment resuspension. As part of the CONCORDE research effort, a four-dimensional biogeochemical/lower trophic level synthesis model for Mississippi Sound and Bight has been developed, based on the Coupled Ocean-Atmosphere-Wave-Sediment Transport (COAWST) Modeling System. This study utilizes CONCORDE's synthesis model to investigate the physical forcing mechanisms affecting the increased suspended particulate matter concentration observed in the Mississippi Bight during spring 2016, and advection pathways between estuarine and shelf waters in the northern Gulf of Mexico. The results show that episodic, advection-driven resuspension is a critical aspect controlling suspended sediment distributions in Mississippi Bight, which has implications for observed spatio-temporal patterns of planktonic species.

  8. Estimating Canopy Dark Respiration for Crop Models

    Science.gov (United States)

    Monje Mejia, Oscar Alberto

    2014-01-01

    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.

  9. LIMITATION OF SOIL RESPIRATION DURING DRY PERIOD

    Czech Academy of Sciences Publication Activity Database

    Pavelka, Marian; Janouš, Dalibor; Acosta, Manuel

    2003-01-01

    Roč. 16, - (2003), s. 47-52. ISBN 80-7157-297-7 R&D Projects: GA MŠk LN00A141; GA AV ČR IBS6087005 Institutional research plan: CEZ:AV0Z6087904 Keywords : moisture * Norway spruce * precipitation * respiration * soil CO2 efflux Subject RIV: EH - Ecology, Behaviour

  10. Internal current generation in respiration chambers

    Science.gov (United States)

    Saborowski, R.; Buchholz, F.

    1998-06-01

    A technical device generating a constant and directed current within a sealed respiration chamber is described. It does not involve any external pumps or tubing. This system is easy to handle, and improved the maintenance of rheotactic pelagic species like the Northern krill ( Meganyctiphanes norvegica, Crustacea) or small fishes ( Gasterosteus aculeatus) under experimental conditions.

  11. 42 CFR 84.1130 - Respirators; description.

    Science.gov (United States)

    2010-10-01

    ...; Pesticide; Paint Spray; Powered Air-Purifying High Efficiency Respirators and Combination Gas Masks § 84...., dust clouds produced in mining, quarrying, and tunneling, and in dusts produced during industrial... respective vapors, or from the chemical reaction between their respective vapors and gases. (3) Air-purifying...

  12. Development of conformal respirator monitoring technology

    International Nuclear Information System (INIS)

    Shonka, J.J.; Weismann, J.J.; Logan, R.J.

    1997-04-01

    This report summarizes the results of a Small Business Innovative Research Phase II project to develop a modular, surface conforming respirator monitor to improve upon the manual survey techniques presently used by the nuclear industry. Research was performed with plastic scintillator and gas proportional modules in an effort to find the most conducive geometry for a surface conformal, position sensitive monitor. The respirator monitor prototype developed is a computer controlled, position-sensitive detection system employing 56 modular proportional counters mounted in molds conforming to the inner and outer surfaces of a commonly used respirator (Scott Model 801450-40). The molds are housed in separate enclosures and hinged to create a open-quotes waffle-ironclose quotes effect so that the closed monitor will simultaneously survey both surfaces of the respirator. The proportional counter prototype was also designed to incorporate Shonka Research Associates previously developed charge-division electronics. This research provided valuable experience into pixellated position sensitive detection systems. The technology developed can be adapted to other monitoring applications where there is a need for deployment of many traditional radiation detectors

  13. Natural isotopic composition of nitrogen as a tracer of origin for suspended organic matter in the Scheldt estuary

    International Nuclear Information System (INIS)

    Mariotti, A.; Lancelot, C.; Billen, G.

    1984-01-01

    The natural isotopic composition of suspended particulate organic nitrogen was determined in the Southern Bight of the North Sea and in the Scheldt estuary. These data show that delta 15 N constitutes a convenient tracer of the origin of the suspended matter. In the winter, in the absence of intensive primary production, the suspended organic matter of the Scheldt estuary is a mixture of two components: a continental detrital component characterized by a low delta value of 1.5per mille and a marine component with a mean delta value of 8per mille. During the phytoplankton flowering period, lasting from early May to October, intensive primary production occurs throughout the estuary giving rise to a third source of organic matter. This material is characterized by high delta values reflecting the isotopic composition of ammonia, the nitrogenous nutrient assimilated by phytoplankton in the estuary. The nitrification process occuring in the mixing area of the Scheldt estuary leads to higher downstream delta values of ammonia (> 20per mille) which permits the distinction between estuarine from fresh-water phytoplankton. Simple isotopic budget calculations show that, both in the upstream part and in the downstream part, autochthonous phytoplanktonic material contributes a major part of the total suspended matter in the Scheldt estuary during summer. (author)

  14. Resuspended contaminated sediments cause sublethal stress to oysters: A biomarker differentiates total suspended solids and contaminant effects.

    Science.gov (United States)

    Edge, Katelyn J; Dafforn, Katherine A; Simpson, Stuart L; Ringwood, Amy H; Johnston, Emma L

    2015-06-01

    Resuspended contaminated sediments represent an important route of contaminant exposure for aquatic organisms. During resuspension events, filter-feeding organisms are exposed to contaminants, in both the dissolved form (at the gills) and the particulate form (in the digestive system). In addition, these organisms must manage the physical stress associated with an increase in total suspended solids (TSS). To date, few studies have experimentally compared the contributions to biological stress of contaminated and clean suspended solids. The authors mixed field-collected sediments (cellular biomarkers (lysosomal membrane stability, lipid peroxidation, and glutathione) were measured to evaluate sublethal toxicity. Lysosomal membrane stability was the most sensitive biomarker for distinguishing effects from resuspended contaminated sediments, as increasing amounts of contaminated TSS increased lysosomal membrane destabilization. The authors' results illustrate the importance of considering contaminant exposures from resuspended sediments when assessing the toxicity of contaminants to aquatic organisms. © 2015 SETAC.

  15. Study on submerged anaerobic membrane bioreactor (SAMBR) treating high suspended solids raw tannery wastewater for biogas production.

    Science.gov (United States)

    Umaiyakunjaram, R; Shanmugam, P

    2016-09-01

    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. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Geochemical importance of isotopic fractionation during respiration

    International Nuclear Information System (INIS)

    Schleser, G.; Foerstel, H.

    1975-01-01

    In 1935 it was found that atmospheric oxygen contained a relatively greater abundance of the 18 O isotope than did the oxygen bound in water (Dole effect). A major contribution to the fractionation of the stable oxygen isotopes should result from the respiration of microorganisms. In this respect our interest centers on the soil because nearly all organic material produced on land is decomposed within the soil. The oceans are less important because the primary productivity on land is twice the value for the oceans. In a first approach we measured the oxygen isotope fractionation during the respiration of E. coli K12 for different respiration rates. These results, accomplished with a chemostat, indicate that the fractionation factor α of the oxygen isotopes increases with the increasing respiratory activity, measured as Q/sub O 2 /. At low dilution rates or growth rates respectively of about 0.05 h -1 , the fractionation factor amounts to 1.006 increasing to 1.017 at dilution rates of about 1.0 h -1 . The results are interpreted as a kinetic mass fractionation due to the slightly different diffusion coefficients of 16 O 2 and 18 O 16 O. The respiration rates in conjunction with the corresponding fractionation data are compared with the respiration rates of typical soil microorganisms such as Azotobacter, in order to deduce fractionation data for these organisms. This is necessary to calculate a mean global fractionation factor. Understanding the Dole effect with these fractionation processes should finally give us the opportunity to calculate gas-exchange rates between the atmosphere and the oceans, on the basis of the behavior of the stable oxygen isotopes

  17. Characterization of particulate matter from the Metropolitan Zone of the Valley of Mexico by scanning electron microscopy and energy-dispersive x-ray analysis

    International Nuclear Information System (INIS)

    Martiez, T.; Lartigue, J.; Avila-Perez, P.; Carapio-Morales, L.; Zarazua, G.; Tejeda, S.

    2005-01-01

    The urban air pollution issue is a concern in many Mega cities, because of hazardous effect to human health. The Metropolitan Zone of the Valley of Mexico (MZMV) is one of the ten largest urban areas around the World with a population of 24.4 million people by the year 2000. One or the 'six criteria pollutants' regulated by Norm (because the hazardous effect to human health) are those commonly designed as Total Suspended Particles (TSP) and Respirable Particles (RP) lower than 10 μm (coarse, PM10 and fine PM2.5). Particulate matter consists of solids or liquid aerosol particles suspended in the air and has diverse chemical composition related to the sources. Under ambient conditions of sampling analysis particulate matter exists almost exclusively in solid phase but can include liquid aerosols such as the heavier components of diesel combustion products and nitric acid. In general particulate matter includes dust, dirt, soot, smoke and liquid droplets emitted in the air by sources such as factories, power plants, cars, fire, construction activities, aircrafts and winds blown dust. In this work the survey of TSP particles an PM10 was carried out with an automatic high volume sampler with an average flow rate of 1.5 m 3 min -1 during 24 h in five monitoring stations of the national network system chosen trying to cover the fourth cardinal directions and the central zone: Xalostoc (XAL) at NE; Tlanepantla (TLA) at NW; Merced (MER) at the downtown; Cerro de la Estrella (CES) at SE and Pedregal (PED) at SW. A sample of l cm 2 was cut from each filter and mounted with a graphite tape on an aluminum sample-holder. The analysis of 100 induvidual particles of each sample were done by scanning electron microscopy and energy-dispersive X-ray microanalysis (EDX). The analysis was performed using a scanning electron microscope PHILLIPS Model XL-30. X-ray analysis is carried out with an energy-dispersive Si(Li) detector Model Saphire, SUTW (super ultra thin window), allowing

  18. Acceptable respiratory protection program and LASL respirator research

    International Nuclear Information System (INIS)

    Skaggs, B.J.

    1979-01-01

    A short history is presented on the LASL Respiratory Protection Training Programs. Then a discussion is given on the major points of an acceptable respiratory protection program utilizing the points required by the Occupational, Safety, and Health Administration (OSHA) Regulation 29 CFR 1910.134. Contributions to respirator research are reviewed. Discussion is presented under the following section headings: program administration; respirator selection; respirator use; fitting and training; respirator maintenance; medical clearance and surveillance; special problems; program evaluation; and documentation

  19. Contribution of root to soil respiration and carbon balance in ...

    Indian Academy of Sciences (India)

    Soil respiration varied from 2.5 to 11.9 g CO2 m-2 d-1 and from 1.5 to 9.3 g CO2 m-2 d-1, and the contribution of root respiration to total soil respiration from 38% to 76% and from 25% to 72% in Communities 1 and 2, respectively. During the growing season (May–September), soil respiration, shoot biomass, live root ...

  20. Suspended Matter, Chl-a, CDOM, Grain Sizes, and Optical Properties in the Arctic Fjord-Type Estuary, Kangerlussuaq, West Greenland During Summer

    DEFF Research Database (Denmark)

    Lund-Hansen, L. C.; Andersen, T. J.; Nielsen, Morten Holtegaard

    2010-01-01

    Optical constituents as suspended particulate matter (SPM), chlorophyll (Chl-a), colored dissolved organic matter (CDOM), and grain sizes were obtained on a transect in the arctic fjord-type estuary Kangerlussuaq (66A degrees) in August 2007 along with optical properties. These comprised diffuse...... water outlet. Values of optical constituents and properties decreased with distance from the melt water outlet to a more or less constant level in central and outer part of the estuary. There was a strong correlation between inorganic suspended matter (SPMI) and diffuse attenuation coefficient K (d...... from the very high turbid melt water outlet to clear marine waters. Results showed a strong spatial variation with high values as for suspended matter concentrations, CDOM, diffuse attenuation coefficient K (d)(PAR), particle beam attenuation coefficients (c (p)), and reflectance R(-0, PAR) at the melt...

  1. Role of solubles and particulates in radionuclide accumulation in the oyster Crassostrea Gigas in the discharge canal of a nuclear power plant

    International Nuclear Information System (INIS)

    Harrison, F.L.; Wong, K.M.; Heft, R.E.

    1972-01-01

    Changes in 54 Mn, 60 Co, 65 Zn, and 137 Cs concentrations were followed in oysters introduced into a discharge canal receiving low-level radioactive waste from a boiling water reactor. Groups of animals were maintained either in filtered or nonfiltered discharge-canal water. They were sampled immediately before and after single radioactive releases and at one-day intervals thereafter. Radionuclide concentrations were determined also in the water and in suspended and settled particulates. In the canal water, concentrations changed rapidly during a release, reaching peak values within 30 minutes. The partition between soluble and particulate (filterable) phases in the water differed with the radionuclide. Continuous sampling of suspended particulates after single releases showed considerable variation in concentrations per liter of water for each radionuclide. Comparisons of animals held in filtered water to those in nonfiltered water showed similar concentrations only for 137 Cs. Results indicate that suspended particulates play an important role in the accumulation of some radionuclides and that resuspension of particulates is an important source between periods of releases. (U.S.)

  2. Nutrients and temperature additively increase stream microbial respiration

    Science.gov (United States)

    David W. P. Manning; Amy D. Rosemond; Vladislav Gulis; Jonathan P. Benstead; John S. Kominoski

    2017-01-01

    Rising temperatures and nutrient enrichment are co‐occurring global‐change drivers that stimulate microbial respiration of detrital carbon, but nutrient effects on the temperature dependence of respiration in aquatic ecosystems remain uncertain. We measured respiration rates associated with leaf litter, wood, and fine benthic organic matter (FBOM) across...

  3. Thermal adaptation of heterotrophic soil respiration in laboratory microcosms.

    Science.gov (United States)

    Mark A. Bradford; Brian W. Watts; Christian A. Davies

    2010-01-01

    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-...

  4. 42 CFR 84.1134 - Respirator containers; minimum requirements.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Respirator containers; minimum requirements. 84... Combination Gas Masks § 84.1134 Respirator containers; minimum requirements. (a) Except as provided in paragraph (b) of this section each respirator shall be equipped with a substantial, durable container...

  5. 21 CFR 892.1970 - Radiographic ECG/respirator synchronizer.

    Science.gov (United States)

    2010-04-01

    ... 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 to...

  6. What controls respiration rate in stored sugarbeet roots

    Science.gov (United States)

    Although respiration is estimated to be responsible for 60 to 80% of the sucrose lost during storage, the mechanisms by which sugarbeet roots regulate their respiration rate are unknown. In plants, respiration rate is regulated by (1) available respiratory capacity, (2) cellular energy status, (3) ...

  7. Redefinition and global estimation of basal ecosystem respiration rate

    DEFF Research Database (Denmark)

    Yuan, Wenping; Luo, Yiqi; Li, Xianglan

    2011-01-01

    Basal ecosystem respiration rate (BR), the ecosystem respiration rate at a given temperature, is a common and important parameter in empirical models for quantifying ecosystem respiration (ER) globally. Numerous studies have indicated that BR varies in space. However, many empirical ER models sti...

  8. Quantifying soil respiration at landscape scales. Chapter 11

    Science.gov (United States)

    John B. Bradford; Michael G. Ryan

    2008-01-01

    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...

  9. Induction by ethylene of cyanide-resistant respiration

    Energy Technology Data Exchange (ETDEWEB)

    Solomos, T.; Laties, G.G.

    1976-05-17

    Ethylene and cyanide induce an increase in respiration in a variety of plant tissues, whereas ethylene has no effect on tissues whose respiration is strongly inhibited by cyanide. It is suggested that the existence of a cyanide-insensitive electron transport path is a prerequisite for stimulation of respiration by ethylene.

  10. DYNAMIC SUFFICIENCY OF THE MAGNETICALLY SUSPENDED TRAIN

    Directory of Open Access Journals (Sweden)

    V. A. Polyakov

    2013-11-01

    Full Text Available Purpose. The basic criterion of the magnetically suspended train's consumer estimation is a quality of its mechanical motion. This motion is realized in unpredictable conditions and, for purposefulness preservation, should adapt to them. Such adaptation is possible only within the limits of system’s dynamic sufficiency. Sufficiency is understood as presence at system of resources, which allow one to realize its demanded motions without violating actual restrictions. Therefore presence of such resources is a necessary condition of preservation of required purposefulness of train's dynamics, and verification of the mentioned sufficiency is the major component of this dynamic research. Methodology. Methods of the set theory are used in work. Desirable and actual approachability spaces of the train are found. The train is considered dynamically sufficient in zones of the specified spaces overlapping. Findings. Within the limits of the accepted treatment of train's dynamic sufficiency, verification of its presence, as well as a stock (or deficiency of preservations can be executed by the search and the subsequent estimation of such overlapping zones. Operatively (directly during motion it can be realized on the train's ODC with use, for example, of computer mathematics system Mathematica. It possesses extensive opportunities of highly efficient and, at the same time, demanding an expense concerning small resources information manipulation. The efficiency of using of created technique is illustrated on an example of vehicle's acceleration research. Calculation is executed with use of the constructed computer model of interaction of an independent traction electromagnetic subsystem of an artifact with its mechanical subsystem. Originality. The technique of verification of the high-speed magnetically suspended train's dynamic sufficiency is developed. The technique is highly efficient, it provides sufficient presentation and demands an expense of the

  11. Geodetic monitoring of suspended particles in rivers

    Science.gov (United States)

    Kamnik, Rok; Maksimova, Daria; Kovačič, Boštjan

    2017-10-01

    There is a trend in modern approach to the management of space of collecting the spatial data, in order to obtain useful information. In this paper a research of suspended particles in the river Drava and Mura will be introduced. The goal is to connect different fields of water management in countries where the rivers Drava and Mura flows in purpose of water management sustainability. The methods such as GNSS for mapping cross sections of the river, the use of ADCP (Acoustic Doppler Current Profiler) measurement system and water sampling to monitor sediment in the water will be presented.

  12. A distinct seasonal pattern of the ratio of soil respiration to total ecosystem respiration in a spruce-dominated forest

    Science.gov (United States)

    E.A. Davidson; A.D. Richardson; K.E. Savage; D.Y. Hollinger

    2006-01-01

    Annual budgets and fitted temperature response curves for soil respiration and ecosystem respiration provide useful information for partitioning annual carbon budgets of ecosystems, but they may not adequately reveal seasonal variation in the ratios of these two fluxes. Soil respiration (Rs) typically contributes 30-80% of...

  13. Particulate carbon in the atmosphere

    International Nuclear Information System (INIS)

    Surakka, J.

    1992-01-01

    Carbonaceous aerosols are emitted to the atmosphere in combustion processes. Carbon particles are very small and have a long residence time in the air. Black Carbon, a type of carbon aerosol, is a good label when transport of combustion emissions in the atmosphere is studied. It is also useful tool in air quality studies. Carbon particles absorb light 6.5 to 8 times stronger than any other particulate matter in the air. Their effect on decreasing visibility is about 50 %. Weather disturbances are also caused by carbon emissions e.g. in Kuwait. Carbon particles have big absorption surface and capacity to catalyze different heterogenous reactions in air. Due to their special chemical and physical properties particulate carbon is a significant air pollution specie, especially in urban air. Average particulate carbon concentration of 5.7 μg/m 2 have been measured in winter months in Helsinki

  14. 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

    International Nuclear Information System (INIS)

    Hissler, Christophe; Probst, Jean-Luc

    2006-01-01

    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 μg m -2 a -1 ). Downstream from the CAP, the bottom sediment, mainly composed of coarse sediment (>63 μm) 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 -2 ) showing that the residence time of Hg in this river is short

  15. Particulate face masks for protection against airborne pathogens - one size does not fit all: an observational study.

    Science.gov (United States)

    Winter, Susan; Thomas, Jane H; Stephens, Dianne P; Davis, Joshua S

    2010-03-01

    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.

  16. Chemical composition shape form and size of suspended solids in the atmosphere carried by rain water

    International Nuclear Information System (INIS)

    Iturbe G, J.L.; Lopez M, B.E.; Torre O, J. De la

    2001-01-01

    The interest of this work is to know about shape form, size and chemical composition of the suspended solids in the atmosphere of Toluca city and which are carried by the rains. The harvest of the samples was carried out during january to november 1999. The separation of the particulate matter from the rain water was realized through centrifugation. The solids were analysed by Scanning Electron Microscopy to know the shape form and size and the chemical composition was determined by X-ray dispersive energy in general form and of some particles individually analysed. The p H was measured to the solutions and the quantification of some dissolved ions by the Icp technique was realized. The results of the solids showed C, O, Na, Mg, Al, Si, S, P, K, Ca, Ti and Fe. Moreover they present sizes which varying from a ten of nanometers until some tens of microns. (Author)

  17. Radionuclide contents in suspended sediments in relation to flood types in the lower Rhone River

    International Nuclear Information System (INIS)

    Zebracki, Mathilde; Eyrolle-Boyer, Frederique; Antonelli, Christelle; Boullier, Vincent; De Vismes-Ott, Anne; Cagnat, Xavier

    2013-01-01

    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 238 U and 232 Th contents and the lowest activity ratio 137 Cs/ (239+240) Pu; these properties could be related to bedrock type and erosion process characteristics and/or to source term differentiation. (authors)

  18. Particulate matter analysis at elementary schools in Curitiba, Brazil.

    Science.gov (United States)

    Avigo, Devanir; Godoi, Ana F L; Janissek, Paulo R; Makarovska, Yaroslava; Krata, Agnieszka; Potgieter-Vermaak, Sanja; Alfoldy, Balint; Van Grieken, René; Godoi, Ricardo H M

    2008-06-01

    The particulate matter indoors and outdoors of the classrooms at two schools in Curitiba, Brazil, was characterised in order to assess the indoor air quality. Information concerning the bulk composition was provided by energy-dispersive x-ray fluorescence (EDXRF). From the calculated indoor/outdoor ratios and the enrichment factors it was observed that S-, Cl- and Zn-rich particles are of concern in the indoor environment. In the present research, the chemical compositions of individual particles were quantitatively elucidated, including low-Z components like C, N and O, as well as higher-Z elements, using automated electron probe microanalysis low Z EPMA. Samples were further analysed for chemical and morphological aspects, determining the particle size distribution and classifying them according to elemental composition associations. Five classes were identified based on major elemental concentrations: aluminosilicate, soot, organic, calcium carbonate and iron-rich particles. The majority of the respirable particulate matter found inside of the classroom was composed of soot, biogenic and aluminosilicate particles. In view of the chemical composition and size distribution of the aerosol particles, local deposition efficiencies in the human respiratory system were calculated revealing the deposition of soot at alveolar level. The results showed that on average 42% of coarse particles are deposited at the extrathoracic level, whereas 24% are deposited at the pulmonary region. The fine fraction showed a deposition rate of approximately 18% for both deposition levels.

  19. Influence of microorganism content in suspended particles on the particle-water partitioning of mercury in semi-enclosed coastal waters.

    Science.gov (United States)

    Jang, Jiyi; Kim, Hyunji; Han, Seunghee

    2014-02-01

    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]algae to transfer Hg to marine food chains. © 2013.

  20. Acoustic measuring techniques for suspended sediment

    Science.gov (United States)

    Gruber, P.; Felix, D.; Storti, G.; Lattuada, M.; Fleckenstein, P.; Deschwanden, F.

    2016-11-01

    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.

  1. Frost Induces Respiration and Accelerates Carbon Depletion in Trees.

    Directory of Open Access Journals (Sweden)

    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.

  2. Frost Induces Respiration and Accelerates Carbon Depletion in Trees.

    Science.gov (United States)

    Sperling, Or; Earles, J Mason; Secchi, Francesca; Godfrey, Jessie; Zwieniecki, Maciej A

    2015-01-01

    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.

  3. Did Respiration or Photosynthesis Come First

    International Nuclear Information System (INIS)

    Broda, E.

    1979-01-01

    The similarity of the mechanisms in photosynthetic and in oxidative phosphorylation suggests a common origin ( convers ion hypothesis). It is proposed that an early form of electron flow with oxidative phosphorylation ("prerespiration"), to terminal electron acceptors available in a reducing biosphere, was supplemented by a photocatalyst capable of a redox reaction. In this way, cyclic photophosphorylation arose. Further stages in evolution were reverse electron flow powered by ATP, to make NADH as a reductant for CO2 , and subsequently noncyclic electron flow. These processes concomitantly provided the oxidants indispensable for full development of oxidative phosphorylation, i.e. for normal respiration: sulphate, O2 and with participation of the nitrificants, nitrite and nitrate. Thus, prerespiration preceded photosynthesis, and this preceded respiration. It is also suggested that nonredox photoprocesses of the Halobacterium type are not part of the mainstream of bioenergetic evolution. They do not lead to photoprocesses with electron flow. (author)

  4. A MEMS turbine prototype for respiration harvesting

    Science.gov (United States)

    Goreke, U.; Habibiabad, S.; Azgin, K.; Beyaz, M. I.

    2015-12-01

    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. Characteristics and source appointment of atmospheric particulate mercury over East China Sea: Implication on the deposition of atmospheric particulate mercury in marine environment.

    Science.gov (United States)

    Duan, Lian; Cheng, Na; Xiu, Guangli; Wang, Fujiang; Chen, Ying

    2017-05-01

    Total Suspended Particulate (TSP) samples were collected at Huaniao Island in northern East China Sea (ECS) from March 2012 to January 2013. Chemical analysis were conducted to measure the concentration of total particulate mercury (TPM) and speciated particulate mercury including HCl-soluble particulate mercury (HPM), elemental particulate mercury (EPM) and residual particulate mercury (RPM). The bromine (Br) and iodine (I) on particles were also detected. The mean concentration of TPM during the study period was 0.23 ± 0.15 ng m -3 , while the obviously seasonal variation was found that the concentrations of TPM in spring, summer, fall and winter were 0.34 ± 0.20 ng m -3 , 0.15 ± 0.03 ng m -3 , 0.15 ± 0.05 ng m -3 and 0.27 ± 0.26 ng m -3 , respectively. The statistically strong correlation of bromine and iodine to HPM was only found in spring with r = 0.81 and 0.77 (p mercury due to the deposition of mercury over the sea. The cluster of air mass across the sea had low concentration of HPM in winter, which suggested that the oxidation of mercury in winter might be related to other oxidants. During the whole sampling period, the air mass from the north of China contributed to the higher concentration of TPM in Huaniao Island. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. CDC WONDER: Daily Fine Particulate Matter

    Data.gov (United States)

    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...

  7. Organic speciation of size-segregated atmospheric particulate matter

    Science.gov (United States)

    Tremblay, Raphael

    Particle size and composition are key factors controlling the impacts of particulate matter (PM) on human health and the environment. A comprehensive method to characterize size-segregated PM organic content was developed, and evaluated during two field campaigns. Size-segregated particles were collected using a cascade impactor (Micro-Orifice Uniform Deposit Impactor) and a PM2.5 large volume sampler. A series of alkanes and polycyclic aromatic hydrocarbons (PAHs) were solvent extracted and quantified using a gas chromatograph coupled with a mass spectrometer (GC/MS). Large volume injections were performed using a programmable temperature vaporization (PTV) inlet to lower detection limits. The developed analysis method was evaluated during the 2001 and 2002 Intercomparison Exercise Program on Organic Contaminants in PM2.5 Air Particulate Matter led by the US National Institute of Standards and Technology (NIST). Ambient samples were collected in May 2002 as part of the Tampa Bay Regional Atmospheric Chemistry Experiment (BRACE) in Florida, USA and in July and August 2004 as part of the New England Air Quality Study - Intercontinental Transport and Chemical Transformation (NEAQS - ITCT) in New Hampshire, USA. Morphology of the collected particles was studied using scanning electron microscopy (SEM). Smaller particles (one micrometer or less) appeared to consist of solid cores surrounded by a liquid layer which is consistent with combustion particles and also possibly with particles formed and/or coated by secondary material like sulfate, nitrate and secondary organic aerosols. Source apportionment studies demonstrated the importance of stationary sources on the organic particulate matter observed at these two rural sites. Coal burning and biomass burning were found to be responsible for a large part of the observed PAHs during the field campaigns. Most of the measured PAHs were concentrated in particles smaller than one micrometer and linked to combustion sources

  8. Characterization of Urban Runoff Pollution between Dissolved and Particulate Phases

    Science.gov (United States)

    Wei, Zhang; Simin, Li; Fengbing, Tang

    2013-01-01

    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. PMID:23935444

  9. Characterization of urban runoff pollution between dissolved and particulate phases.

    Science.gov (United States)

    Wei, Zhang; Simin, Li; Fengbing, Tang

    2013-01-01

    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.

  10. Modifying Char Dustcake Pressure Drop Using Particulate Additives

    Energy Technology Data Exchange (ETDEWEB)

    Landham, C.; Dahlin, R.S.; Martin, R.A.; Guan, X.

    2002-09-19

    Coal gasification produces residual particles of coal char, coal ash, and sorbent that are suspended in the fuel gas stream exiting the gasifier. In most cases, these particles (referred to, hereafter, simply as char) must be removed from the stream prior to sending the gas to a turbine, fuel cell, or other downstream device. Currently, the most common approach to cleaning the gas stream at high temperature and pressure is by filtering the particulate with a porous ceramic or metal filter. However, because these dusts frequently have small size distributions, irregular morphology, and high specific surface areas, they can have very high gas flow resistance resulting in hot-gas filter system operating problems. Typical of gasification chars, the hot-gas filter dustcakes produced at the Power Systems Development Facility (PSDF) during recent coal gasification tests have had very high flow resistance (Martin et al, 2002). The filter system has been able to successfully operate, but pressure drops have been high and filter cleaning must occur very frequently. In anticipation of this problem, a study was conducted to investigate ways of reducing dustcake pressure drop. This paper will discuss the efficacy of adding low-flow-resistance particulate matter to the high-flow-resistance char dustcake to reduce dustcake pressure drop. The study had two parts: a laboratory screening study and confirming field measurements at the PSDF.

  11. Particulate Matter: a closer look

    NARCIS (Netherlands)

    Buijsman E; Beck JP; Bree L van; Cassee FR; Koelemeijer RBA; Matthijsen J; Thomas R; Wieringa K; LED; MGO

    2005-01-01

    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

  12. Transport phenomena in particulate systems

    CERN Document Server

    Freire, José Teixeira; Ferreira, Maria do Carmo

    2012-01-01

    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.

  13. SIZE DISTRIBUTION AND RATE OF PRODUCTION OF AIRBORNE PARTICULATE MATTER GENERATED DURING METAL CUTTING

    International Nuclear Information System (INIS)

    Ebadian, M.A.; Dua, S.K.; Hillol Guha

    2001-01-01

    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 microm) 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

  14. Global Particulate Matter Source Apportionment

    Science.gov (United States)

    Lamancusa, C.; Wagstrom, K.

    2017-12-01

    As our global society develops and grows it is necessary to better understand the impacts and nuances of atmospheric chemistry, in particular those associated with atmospheric particulate matter. We have developed a source apportionment scheme for the GEOS-Chem global atmospheric chemical transport model. While these approaches have existed for several years in regional chemical transport models, the Global Particulate Matter Source Apportionment Technology (GPSAT) represents the first incorporation into a global chemical transport model. GPSAT runs in parallel to a standard GEOS-Chem run. GPSAT uses the fact that all molecules of a given species have the same probability of undergoing any given process as a core principle. This allows GPSAT to track many different species using only the flux information provided by GEOS-Chem's many processes. GPSAT accounts for the change in source specific concentrations as a result of aqueous and gas-phase chemistry, horizontal and vertical transport, condensation and evaporation on particulate matter, emissions, and wet and dry deposition. By using fluxes, GPSAT minimizes computational cost by circumventing the computationally costly chemistry and transport solvers. GPSAT will allow researchers to address many pertinent research questions about global particulate matter including the global impact of emissions from different source regions and the climate impacts from different source types and regions. For this first application of GPSAT, we investigate the contribution of the twenty largest urban areas worldwide to global particulate matter concentrations. The species investigated include: ammonium, nitrates, sulfates, and the secondary organic aerosols formed by the oxidation of benzene, isoprene, and terpenes. While GPSAT is not yet publically available, we will incorporate it into a future standard release of GEOS-Chem so that all GEOS-Chem users will have access to this new tool.

  15. Particulate Matter Concentrations in East Oakland's High Street Corridor

    Science.gov (United States)

    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.

    2012-12-01

    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.

  16. IMPACT OF SIPHONING ACTIVITY AND NATURALLY SUSPENDED PARTICLE LOAD ON MUSSEL KILL by PSEUDOMONAS FLUORESCENS

    International Nuclear Information System (INIS)

    Daniel Molloy

    2003-01-01

    Under this USDOE-NETL contract, the bacterium Pseudomonas fluorescens is being developed as a biocontrol agent for zebra mussels. The specific purpose of the contract is to identify biotic and abiotic factors that affect mussel kill. Ingestion of these bacteria by zebra mussels is required to achieve kill, and tests evaluating factors that relate to mussel feeding are contained in this report. Specifically the impact of the following two factors were investigated: (1) Mussel siphoning behavior--In nature, zebra mussels typically have their two shells spread apart and their inhalant siphon tube extended from between their shells for taking food particles into their mantle cavities (Fig. 1). Our tests indicated that there is a direct correlation between mussel siphoning activity and mussel mortality achieved by a bacterial treatment. Therefore, to encourage mussel feeding on bacteria, future pipe treatments within power plants should be carried out using procedures which minimize disturbance to mussel siphoning. 2. Naturally suspended particle loads--Since bacterial cells are lethal only if ingested by mussels, waters containing very high levels of naturally suspended particles might reduce the mortality that can be achieved by a bacterial treatment. If true, this inhibition might occur as a result of particle exclusion, i.e., there could be reduced ingestion of bacterial cells since they represent a reduced percentage of all particles ingested. Our tests indicated that a range of particle concentrations that might naturally exist in a turbid river did not inhibit mussel kill by the bacterial cells, but that an artificially high load of natural particles was capable of causing a reduction in kill. To be conservative, therefore, future pipe treatments should be timed to occur when intake waters have relatively low quantities of naturally suspended particulate matter

  17. IMPACT OF SIPHONING ACTIVITY AND NATURALLY SUSPENDED PARTICLE LOAD ON MUSSEL KILL by PSEUDOMONAS FLUORESCENS

    Energy Technology Data Exchange (ETDEWEB)

    Daniel Molloy

    2003-08-04

    Under this USDOE-NETL contract, the bacterium Pseudomonas fluorescens is being developed as a biocontrol agent for zebra mussels. The specific purpose of the contract is to identify biotic and abiotic factors that affect mussel kill. Ingestion of these bacteria by zebra mussels is required to achieve kill, and tests evaluating factors that relate to mussel feeding are contained in this report. Specifically the impact of the following two factors were investigated: (1) Mussel siphoning behavior--In nature, zebra mussels typically have their two shells spread apart and their inhalant siphon tube extended from between their shells for taking food particles into their mantle cavities (Fig. 1). Our tests indicated that there is a direct correlation between mussel siphoning activity and mussel mortality achieved by a bacterial treatment. Therefore, to encourage mussel feeding on bacteria, future pipe treatments within power plants should be carried out using procedures which minimize disturbance to mussel siphoning. 2. Naturally suspended particle loads--Since bacterial cells are lethal only if ingested by mussels, waters containing very high levels of naturally suspended particles might reduce the mortality that can be achieved by a bacterial treatment. If true, this inhibition might occur as a result of particle exclusion, i.e., there could be reduced ingestion of bacterial cells since they represent a reduced percentage of all particles ingested. Our tests indicated that a range of particle concentrations that might naturally exist in a turbid river did not inhibit mussel kill by the bacterial cells, but that an artificially high load of natural particles was capable of causing a reduction in kill. To be conservative, therefore, future pipe treatments should be timed to occur when intake waters have relatively low quantities of naturally suspended particulate matter.

  18. Organics and Suspended Solids Removal from Hospital

    Directory of Open Access Journals (Sweden)

    Fakhri Y. Hmood

    2013-05-01

    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.  

  19. Batch fabrication of nanotubes suspended between microelectrodes

    DEFF Research Database (Denmark)

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

    2007-01-01

    be done with a simple lift-off process with standard photolithographic resist. An applied electric field is sustained between the microelectrodes during CVD to guide the nanotube growth. Comparison with simulations shows that the location and the orientation of the grown carbon nanotubes (CNT) correspond...... to the regions of maximum electric field, enabling accurate positioning of a nanotube by controlling the shape of the microelectrodes. The CNT bridges are deflected tens of nm when a DC voltage is applied between the nanotube and a gate microelectrode indicating that the clamping through the catalyst particles...... is not only mechanically stable but also electrical conducting. This method could be used to fabricate nanoelectromechanical systems based on suspended double clamped CNTs depending only on photolithography and standard Cleanroom processes....

  20. Plant species richness regulates soil respiration through changes in productivity.

    Science.gov (United States)

    Dias, André Tavares Corrêa; van Ruijven, Jasper; Berendse, Frank

    2010-07-01

    Soil respiration is an important pathway of the C cycle. However, it is still poorly understood how changes in plant community diversity can affect this ecosystem process. Here we used a long-term experiment consisting of a gradient of grassland plant species richness to test for effects of diversity on soil respiration. We hypothesized that plant diversity could affect soil respiration in two ways. On the one hand, more diverse plant communities have been shown to promote plant productivity, which could increase soil respiration. On the other hand, the nutrient concentration in the biomass produced has been shown to decrease with diversity, which could counteract the production-induced increase in soil respiration. Our results clearly show that soil respiration increased with species richness. Detailed analysis revealed that this effect was not due to differences in species composition. In general, soil respiration in mixtures was higher than would be expected from the monocultures. Path analysis revealed that species richness predominantly regulates soil respiration through changes in productivity. No evidence supporting the hypothesized negative effect of lower N concentration on soil respiration was found. We conclude that shifts in productivity are the main mechanism by which changes in plant diversity may affect soil respiration.

  1. Treatment of suspended solids and heavy metals from urban stormwater runoff by a tree box filter.

    Science.gov (United States)

    Geronimo, F K F; Maniquiz-Redillas, M C; Tobio, J A S; Kim, L H

    2014-01-01

    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. Evaluation of the filtration performance of NIOSH-approved N95 filtering facepiece respirators by photometric and number-based test methods.

    Science.gov (United States)

    Rengasamy, Samy; Miller, Adam; Eimer, Benjamin C

    2011-01-01

    N95 particulate filtering facepiece respirators are certified by measuring penetration levels photometrically with a presumed severe case test method using charge neutralized NaCl aerosols at 85 L/min. However, penetration values obtained by photometric methods have not been compared with count-based methods using contemporary respirators composed of electrostatic filter media and challenged with both generated and ambient aerosols. To better understand the effects of key test parameters (e.g., particle charge, detection method), initial penetration levels for five N95 model filtering facepiece respirators were measured using NaCl aerosols with the aerosol challenge and test equipment employed in the NIOSH respirator certification method (photometric) and compared with an ultrafine condensation particle counter method (count based) for the same NaCl aerosols as well as for ambient room air particles. Penetrations using the NIOSH test method were several-fold less than the penetrations obtained by the ultrafine condensation particle counter for NaCl aerosols as well as for room particles indicating that penetration measurement based on particle counting offers a more difficult challenge than the photometric method, which lacks sensitivity for particles photometric method may not be a more challenging aerosol test method. Filter penetrations can vary among workplaces with different particle size distributions, which suggests the need for the development of new or revised "more challenging" aerosol test methods for NIOSH certification of respirators.

  3. Arsenic speciation in water, suspended particles, and coastal organisms from the Taehwa River Estuary of South Korea

    International Nuclear Information System (INIS)

    Hong, Seongjin; Kwon, Hye-Ok; Choi, Sung-Deuk; Lee, Jung-Suk; Khim, Jong Seong

    2016-01-01

    Water, suspended particulate matter (SPM), and biota samples were collected from the Taehwa River Estuary to determine the distributions, partitioning, and bioaccumulation of arsenicals. Six forms of As were quantitated by the use of HPLC-ICP/MS. As was found mainly near urban and industrial areas, and inorganic As V was the predominant As form in both water and SPM. Particulate arsenicals were found at the greatest concentrations in coarse particles (> 180 μm), followed by medium (30–180 μm) and fine (0.45–30 μm) particles, in freshwater. Arsenical concentrations were similar across the three particle fractions in saltwater. Field-based distribution coefficient (K d ) values for As depended strongly on SPM, with a less robust dependence on salinity. Concentrations of As were greater in macroalgae than in marine animals, such as fishes, bivalves, crabs, shrimps, and gastropods. Overall, the results of the present study provide useful information on the behaviors and fate of arsenicals in an estuarine environment. - Highlights: •Concentrations of As were greater in industrial and urban areas than in suburban area. •The predominant form of As in water and suspended particles was inorganic As V . •Particle-size distributions of arsenicals differed between freshwater and saltwater. •The K d values for As depended strongly on the presence of SPMs along the estuary. •Greater concentrations of arsenicals were found in macroalgae than in marine animals.

  4. Numerical Simulations of the Impact and Spreading of a Particulate Drop on a Solid Substrate

    Directory of Open Access Journals (Sweden)

    Hyun Jun Jeong

    2012-01-01

    Full Text Available We present two-dimensional numerical simulations of the impact and spreading of a droplet containing a number of small particles on a flat solid surface, just after hitting the solid surface, to understand particle effects on spreading dynamics of a particle-laden droplet for the application to the industrial inkjet printing process. The Navier-Stokes equation is solved by a finite-element-based computational scheme that employs the level-set method for the accurate interface description between the drop fluid and air and a fictitious domain method for suspended particles to account for full hydrodynamic interaction. Focusing on the particle effect on droplet spreading and recoil behaviors, we report that suspended particles suppress the droplet oscillation and deformation, by investigating the drop deformations for various Reynolds numbers. This suppressed oscillatory behavior of the particulate droplet has been interpreted with the enhanced energy dissipation due to the presence of particles.

  5. Does the increased air humidity affect soil respiration and carbon stocks?

    Science.gov (United States)

    Kukumägi, Mai; Celi, Luisella; Said-Pullicino, Daniel; Kupper, Priit; Sõber, Jaak; Lõhmus, Krista; Kutti, Sander; Ostonen, Ivika

    2013-04-01

    Climate manipulation experiments at ecosystem-scale enable us to simulate, investigate and predict changes in carbon balance of forest ecosystems. Considering the predicted increase in air humidity and precipitation for northern latitudes, this work aimed at investigating the effect of increased air humidity on soil respiration, distribution of soil organic matter (SOM) among pools having different turnover times, and microbial, fine root and rhizome biomass. The study was carried out in silver birch (Betula pendula Roth.) and hybrid aspen (Populus tremula L. × P. tremuloides Michx.) stands in a Free Air Humidity Manipulation (FAHM) experimental facility containing three humidified (H; on average 7% above current ambient levels since 2008) and three control (C) plots. Soil respiration rates were measured monthly during the growing season using a closed dynamic chamber method. Density fractionation was adopted to separate SOM into two light fractions (free and aggregate-occluded particulate organic matter, fPOM and oPOM respectively), and one heavy fraction (mineral-associated organic matter, MOM). The fine root and rhizome biomass and microbial data are presented for silver birch stands only. In 2011, after 4 growing seasons of humidity manipulation soil organic carbon contents were significantly higher in C plots than H plot (13.5 and 12.5 g C kg-1, respectively), while soil respiration tended to be higher in the latter. Microbial biomass and basal respiration were 13 and 14% higher in H plots than in the C plots, respectively. Twice more fine roots of trees were estimated in H plots, while the total fine root and rhizome biomass (tree + understory) was similar in C and H plots. Fine root turnover was higher for both silver birch and understory roots in H plots. Labile SOM light fractions (fPOM and oPOM) were significantly smaller in H plots with respect to C plots (silver birch and hybrid aspen stands together), whereas no differences were observed in the

  6. Estuarine modification of dissolved and particulate trace metals in major rivers of East-Hainan, China

    Science.gov (United States)

    Fu, Jun; Tang, Xiao-Liang; Zhang, Jing; Balzer, Wolfgang

    2013-04-01

    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

  7. Mesozooplankton production, grazing and respiration in the Bay of Bengal: Implications for net heterotrophy

    Science.gov (United States)

    Fernandes, Veronica; Ramaiah, N.

    2016-03-01

    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.

  8. Interactions of radionuclides in water, particulates, and oysters in the discharge canal of a nuclear power plant

    International Nuclear Information System (INIS)

    Harrison, F.L.; Wong, K.M.; Heft, R.E.

    1976-01-01

    This study was designed to provide data for dynamic modeling of radioactive pollutants in marine ecosystems adjacent to nuclear power plants. The data are relevant to the dynamics of radionuclide transfer among seawater, suspended particulates, sediments, and biota. Gamma-emitting radionuclides ( 54 Mn, 60 Co, 65 Zn, and 137 Cs) were followed in the water and particulates, as well as in oysters introduced into the discharge canal of the boiling water reactor of the Humboldt Bay Power Plant near Eureka, California. The liquid waste was introduced into the canal at irregular intervals and contained radionuclides at extremely low but variable concentrations. Radionuclides were determined in the oysters, water, and particulates after single releases (over about 6 hr) and over a long series of releases

  9. Energy values of suspended detritus in Andaman Sea

    Digital Repository Service at National Institute of Oceanography (India)

    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...

  10. Dynamic model of movement of mine suspended monorail

    Directory of Open Access Journals (Sweden)

    Viktor GUTAREVYCH

    2014-03-01

    Full Text Available In the article we have developed the dynamic model of interaction of rolling stock during the movement, on the suspended monorail, taking into account the side-sway. We have received the motion equations, carried out their analysis and determined the own oscillation frequencies of rolling stock of suspended monorail.

  11. Soil erosion and suspended sediment transport in an agricultural watershed of Brie. Use of radioactive and magnetic tracers

    International Nuclear Information System (INIS)

    Sogon, St.

    1999-01-01

    The degradation of the water quality of rivers by the particulates and the associated pollutants coming from the erosion of agricultural soils is analyzed in the framework of the Piren-Seine program. The area under study is the catchment basin of the Grand Morin river in the Brie plateau (SE of the Paris basin, France). The 137 Cs (T1/2 = 30 years), mainly produced during the atmospheric nuclear tests (1952-1963) is rapidly and strongly fixed to the soil particulates and can be used as a tracer of their migration. These fallout are considered as uniform at the catchment basin scale but those coming from the Tchernobyl accident disturb this labelling. The image obtained from the implementation of the method (reference activity: 3170 Bq/m 2 in January 1, 1996, with 792 Bq/m 2 coming from Tchernobyl) on a 11.2 Ha field (Hardy field, 160 carrots) shows a badly structured 137 Cs redistribution. The mosaic of erosion and accumulation areas shows that the relays represent a major element of the erosion dynamics. No particular element of the landscape can explain the redistribution of the particulates, but the upward part has a more complex functioning with respect to the downward part which has more inclined slopes (>5%). The measurement of the particulates migration on the southern slope (3.5 Ha) of the field allows to calculate a sedimentary status (net erosion ratio: 4 kg/m 2 /year; sedimentary supply ratio: 40%). The study of the suspended matter exported by a buried drainage network (specific of the agriculture of the Brie region) shows strong 137 Cs, 7 Be (T1/2 = 53 days) and 210 Pb (T1/2 = 22 years) activities characteristic of a direct and fast transfer of the thin clay fraction (0.5-0.1 μm) coming from the ploughed layer. In the upstream part of the Vannetin river, the activity of the suspended matter remains identical to the one of the drainage network showing their influence. On the other hand, in the mid-stream part, the sources of suspended matter are

  12. Partitioning of ecosystem respiration in a beech forest

    DEFF Research Database (Denmark)

    Brændholt, Andreas; Ibrom, Andreas; Larsen, Klaus Steenberg

    2018-01-01

    Terrestrial ecosystem respiration (Reco) represents a major component of the global carbon cycle. It consists of many sub-components, such as aboveground plant respiration and belowground root and microbial respiration, each of which may respond differently to abiotic factors, and thus to global...... of Reco in a temperate beech forest at diel, seasonal and annual time scales. Reco was measured by eddy covariance while respiration rates from soil, tree stems and isolated coarse tree roots were measured bi-hourly by an automated closed-chamber system. Soil respiration (Rsoil) was measured in intact...... plots, and heterotrophic Rsoil was measured in trenched plots. Tree stem (Rstem) and coarse root (Rroot) respiration were measured by custom made closed-chambers. We found that the contribution of Rstem to total Reco varied across the year, by only accounting for 6% of Reco during winter and 16% during...

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

    Digital Repository Service at National Institute of Oceanography (India)

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

    spatial differences were observed for the offshore stations in SPIM (Table 1). 3.4. POC and % POC In the Bay of Bengal, the surface POC concentrations ranged from 4.3 to 11.1 µMC, 3.1 to 10.9 µMC, and 4.3 to 9.0 µMC in the SWM, FIM, and SPIM.... This is NIO contribution no. 4435. 10 References Bale, A., Morris, A., 1998. Organic carbon in suspended particulate material in the North Sea: effect of mixing resuspended and background particles. Cont. Shelf Res. 18, 1333 –1345. Bates, N. R., Dennis, A...

  14. PIXE analysis of airborne particulate matter from Xalostoc, Mexico: winter to summer comparison

    International Nuclear Information System (INIS)

    Flores M, J.; Aldape, F.; Diaz, R.V.; Hernandez-Mendez, B.; Garcia G, R.

    1999-01-01

    A study of elemental contents in airborne particulate matter from the industrial city of Xalostoc, Estado de Mexico, was performed using PIXE. The place has a great variety of industries, it is a heavily populated, and it is a part of Mexico City's conurbation, thus contributing significantly to its atmospheric pollution. At present, there is few information available about elemental contents in airborne particulate matter from that region. In this study, two sets of samples of airborne particulate matter were collected daily during periods of four weeks in summer 1996 and winter 1997; two samples a day, 12 h each, night-time and day-time. Results revealed important information about elemental contents in airborne particulate matter from that area, especially in the respirable fraction PM 2.5 . Comparison of night and day figures showed the presence of some elements such as Cu, Zn, and Pb, attributed, as it was expected, to uninterrupted industrial processes. Appearance of some other elements was more consistent only in either day-time or night-time due to diurnal or nocturnal industrial activities, or produced by human activities such as fuel combustion of automotive vehicles. Comparison of winter to summer results showed some other important features such as higher concentrations of pollutants in winter, because of the dry and cold weather, while summer samples exhibited lower concentrations mainly due to the presence of rain showers

  15. Dynamics of coarse particulate matter in the turbidity maximum zone of the Gironde Estuary

    Science.gov (United States)

    Fuentes-Cid, Ana; Etcheber, Henri; Schmidt, Sabine; Abril, Gwenaël; De-Oliveira, Eric; Lepage, Mario; Sottolichio, Aldo

    2014-01-01

    There is a lack of studies devoted to coarse particulate matter (CPM) in estuaries, although this fraction can disturb activities that filter large volumes of water, such as industrial or fishery activities. In the macrotidal and highly-turbid Gironde Estuary, a monthly sampling of CPM was performed in 2011 and 2013 at two stations in the Turbidity Maximum Zone (TMZ) to understand its seasonal, tidal and hydrological dynamics. Regardless of the season and station, low quantities of CPM (few g m-3) were observed in comparison with suspended particulate matter (several 103 g m-3). The highest concentrations were consistently recorded in bottom waters and at the upstream station. Whereas there is no clear link between the CPM present in the column water and spring or neap tides, an increase in the CPM size has been identified at the two stations after a flood event, fact potentially critical regarding filtering functioning of estuarine activities.

  16. Study of particulates and heavy elements in air of some Syrian cities

    International Nuclear Information System (INIS)

    Othman, I.; Al-Oudat, M.; Al-Rayes, A. H.; Al- Kharfan, K.

    1999-11-01

    A study of air pollution in different sites of five Syrian cities (Damascus, Aleppo, Tartous, Homs, and Sweda) was carried out. The concentration of total suspended particulate (TSP), particulate less than 10 microns (PM 10) and less than 3 microns (PM 3) were measured using high volume air sampler (HVAS). Heavy element concentration, Pb, Cd, Zn, and Cu were also determined using anodic stripping voltametry. The result showed that TSP, PM 10 and PM 3 were higher than WHO standards in several times. Mean lead concentrations ranged between 0.58 and 2.96 μg/m 3 and 0.56 and 1.53 μg/m 3 in Damascus and Aleppo respectively, while in the other cities these concentrations were less than WHO standards (0.5 - 1 μg/m 3 ). (author)

  17. Tillage Effects on Soil Properties & Respiration

    Science.gov (United States)

    Rusu, Teodor; Bogdan, Ileana; Moraru, Paula; Pop, Adrian; Duda, Bogdan; Cacovean, Horea; Coste, Camelia

    2015-04-01

    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

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

    DEFF Research Database (Denmark)

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

    1999-01-01

    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...... decay, predation and death-regeneration are discussed. From recent microbial research it has become evident that cells do not die by themselves. Bacteria are however subject to predation by protozoa. Bacteria store reserve polymers that in absence of external substrate are used for growth...

  19. Protective coatings for commercial particulates

    DEFF Research Database (Denmark)

    Kindl, B.; Teng, Y.H.; Liu, Y.L.

    1994-01-01

    SiC/Al composites are in large-scale production with Al-Si alloy matrices. The same composites with pure Al or low Si matrices need diffusion barriers on the SiC reinforcement to control the interfacial reaction. The present paper describes various approaches taken to obtain protective coatings...... of alumina and zirconia on SiC particulates by sol-gel techniques. Aqueous and organic precursors have been used. The extent of the reaction, i.e., the Si and Al4C3 content in the matrix, was determined by differential thermal analysis and X-ray diffraction. The reaction rates of some coated particulates...... in liquid Al are decreased by as much as one order of magnitude during the first 15 min of immersion. Pretreatments of the SiC surface, the composition and thickness of the coating interphase and heat treatments of the coated materials have been studied, and are discussed in relation to their effect...

  20. Development of an Advanced Respirator Fit Test Headform (Postprint)

    Science.gov (United States)

    2012-11-01

    N95 filtering facepiece respirators (FFRs) for pro - tection studies against viable airborne particles. A Static (i.e., non-moving, non-speaking...requiredto wear respirators to reduce their exposure to air- borne hazards.(1) The U.S. Occupational Safety and Health Administration ( OSHA ) Respiratory...13 workplace protection factors.(9,10). Inward leakage (IL) of con - taminants into a respirator facepiece has been described as a combination of

  1. Soil Respiration under Different Land Uses in Eastern China

    Science.gov (United States)

    Fan, Li-Chao; Yang, Ming-Zhen; Han, Wen-Yan

    2015-01-01

    Land-use change has a crucial influence on soil respiration, which further affects soil nutrient availability and carbon stock. We monitored soil respiration rates under different land-use types (tea gardens with three production levels, adjacent woodland, and a vegetable field) in Eastern China at weekly intervals over a year using the dynamic closed chamber method. The relationship between soil respiration and environmental factors was also evaluated. The soil respiration rate exhibited a remarkable single peak that was highest in July/August and lowest in January. The annual cumulative respiration flux increased by 25.6% and 20.9% in the tea garden with high production (HP) and the vegetable field (VF), respectively, relative to woodland (WL). However, no significant differences were observed between tea gardens with medium production (MP), low production (LP), WL, and VF. Soil respiration rates were significantly and positively correlated with organic carbon, total nitrogen, and available phosphorous content. Each site displayed a significant exponential relationship between soil respiration and soil temperature measured at 5 cm depth, which explained 84–98% of the variation in soil respiration. The model with a combination of soil temperature and moisture was better at predicting the temporal variation of soil respiration rate than the single temperature model for all sites. Q10 was 2.40, 2.00, and 1.86–1.98 for VF, WL, and tea gardens, respectively, indicating that converting WL to VF increased and converting to tea gardens decreased the sensitivity of soil respiration to temperature. The equation of the multiple linear regression showed that identical factors, including soil organic carbon (SOC), soil water content (SWC), pH, and water soluble aluminum (WSAl), drove the changes in soil respiration and Q10 after conversion of land use. Temporal variations of soil respiration were mainly controlled by soil temperature, whereas spatial variations were

  2. 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

    Energy Technology Data Exchange (ETDEWEB)

    Dierssen, H

    1999-07-01

    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)

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

    Indian Academy of Sciences (India)

    Unknown

    The linear regression relationship between soil respiration and root biomass was used to determine the .... 10 days, sieved 50 g soil samples were placed in a 100 ml beaker and a 250 ..... Comparatively, the method can take multi-samples by ...

  4. ESTIMATING ROOT RESPIRATION IN SPRUCE AND BEECH: DECREASES IN SOIL RESPIRATION FOLLOWING GIRDLING

    Science.gov (United States)

    A study was undertaken to follow seasonal fluxes of CO2 from soil and to estimate the contribution of autotrophic (root + mycorrhizal) to total soil respiration (SR) in a mixed stand of European beech (Fagus sylvatica) and Norway spruce (Picea abies) near Freising, Germany. Matu...

  5. [The development of a respiration and temperature monitor].

    Science.gov (United States)

    Du, X; Wu, B; Liu, Y; He, Q; Xiao, J

    2001-12-01

    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. Metabolic interactions between methanogenic consortia and anaerobic respiring bacteria

    DEFF Research Database (Denmark)

    Stams, A.J.; Oude Elferink, S.J.; Westermann, Peter

    2003-01-01

    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...... consortia. Despite the potentially adverse effects, only few inorganic electron acceptors potentially utilizable for anaerobic respiration have been investigated with respect to negative interactions in anaerobic digesters. In this chapter we review competitive and inhibitory interactions between anaerobic...... respiring populations and methanogenic consortia in bioreactors. Due to the few studies in anaerobic digesters, many of our discussions are based upon studies of defined cultures or natural ecosystems...

  7. Respirator studies for the ERDA Division of Safety, Standards, and Compliance. Progress report, July 1, 1974--June 30, 1975

    International Nuclear Information System (INIS)

    Douglas, D.D.; Hack, A.L.; Davis, T.O.; Shafer, C.; Moore, T.O.; Richards, C.P.; Revoir, W.H.

    1976-08-01

    Major accomplishments during FY 1975 were the initiation of a respirator research program to investigate the physiological effects of wearing a respirator under stress, assisting ERDA contractors by providing information and training concerning respirator programs, quality assurance of respirators, and respirator applications. A newsletter of respirator developments for ERDA contractor personnel was published, and a Respirator Symposium was conducted

  8. Lung cancer, cardiopulmonary mortality, and long-term exposure to fine particulate air pollution

    Energy Technology Data Exchange (ETDEWEB)

    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)

    2003-03-06

    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.

  9. Seasonal Variability of Airborne Particulate Matter and Bacterial Concentrations in Colorado Homes

    Directory of Open Access Journals (Sweden)

    Nicholas Clements

    2018-04-01

    Full Text Available Aerosol measurements were collected at fifteen homes over the course of one year in Colorado (USA to understand the temporal variability of indoor air particulate matter and bacterial concentrations and their relationship with home characteristics, inhabitant activities, and outdoor air particulate matter (PM. Indoor and outdoor PM2.5 concentrations averaged (±st. dev. 8.1 ± 8.1 μg/m3 and 6.8 ± 4.5 μg/m3, respectively. Indoor PM2.5 was statistically significantly higher during summer compared to spring and winter; outdoor PM2.5 was significantly higher for summer compared to spring and fall. The PM2.5 I/O ratio was 1.6 ± 2.4 averaged across all homes and seasons and was not statistically significantly different across the seasons. Average indoor PM10 was 15.4 ± 18.3 μg/m3 and was significantly higher during summer compared to all other seasons. Total suspended particulate bacterial biomass, as determined by qPCR, revealed very little seasonal differences across and within the homes. The qPCR I/O ratio was statistically different across seasons, with the highest I/O ratio in the spring and lowest in the summer. Using one-minute indoor PM10 data and activity logs, it was observed that elevated particulate concentrations commonly occurred when inhabitants were cooking and during periods with elevated outdoor concentrations.

  10. Penetration of asbestos fibers in respirator filters

    International Nuclear Information System (INIS)

    Cheng, Yung-Sung; Pearson, S.D.; Rohrbacher, K.D.; Yeh, Hsu-Chi.

    1994-01-01

    Currently, the health risks associated with asbestos have restricted its use and created a growing asbestos abatement industry with a need for respirator filters that are effective for worker protection. The main purpose of this project is to determine the influence of fiber size, electrostatic charge, and flow rate on the penetration of asbestos fibers in respirator filter cartridges. The study includes four types of filters each tested at two flow rates: the AO-R57A, a dual cartridge HEPA filter tested at 16 and 42.5 L/min; the MSA-S, a dust and mist filter tested at 16 and 42.5 L/min; the MSA-A power filter tested at 32 and 85 L/min; and the 3M-8710, a low-efficiency disposable face mask filter tested at 32 and 85 L/min. The three types of asbestos fibers used (amosite, crocidolite, and chrysotile) ranged in length from 0.04-0.5 μm and in aspect ratio (ratio of length to diameter) from 3 to 60. The fibers were used in both charged and neutralized forms. The results from amosite fibers are reported here

  11. Can we distinguish autotrophic respiration from heterotrophic respiration in a field site using high temporal resolution CO2 flux measurements?

    Science.gov (United States)

    Biro, Beatrice; Berger, Sina; Praetzel, Leandra; Blodau, Christian

    2016-04-01

    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

  12. Aged riverine particulate organic carbon in four UK catchments

    International Nuclear Information System (INIS)

    Adams, Jessica L.; Tipping, Edward; Bryant, Charlotte L.; Helliwell, Rachel C.; Toberman, Hannah; Quinton, John

    2015-01-01

    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 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 14 C value for the 7 sites of 91.2 pMC corresponded to an average age of 680 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 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- 14 C topsoil organic matter by mineralisation during riverine transport. The significantly lower average PO 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 14 C in rivers draining catchments with low erosion rates. - Highlights:

  13. Aged riverine particulate organic carbon in four UK catchments

    Energy Technology Data Exchange (ETDEWEB)

    Adams, Jessica L., E-mail: jesams@ceh.ac.uk [Centre for Ecology and Hydrology, Lancaster Environment Centre, Lancaster, LA1 4AP (United Kingdom); Tipping, Edward, E-mail: et@ceh.ac.uk [Centre for Ecology and Hydrology, Lancaster Environment Centre, Lancaster, LA1 4AP (United Kingdom); Bryant, Charlotte L., E-mail: charlotte.bryant@glasgow.ac.uk [NERC Radiocarbon Facility, East Kilbride G75 0QF, Scotland (United Kingdom); Helliwell, Rachel C., E-mail: rachel.helliwell@hutton.ac.uk [The James Hutton Institute, Craigiebuckler, Aberdeen AB15 8QH Scotland (United Kingdom); Toberman, Hannah, E-mail: hannahtoberman@hotmail.com [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: j.quinton@lancaster.ac.uk [Lancaster Environment Centre, Lancaster University, Lancaster LA1 4YQ (United Kingdom)

    2015-12-01

    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

  14. On-road particulate emission measurement

    Science.gov (United States)

    Mazzoleni, Claudio

    Particulate matter (PM) suspended in the atmosphere has harmful health effects, contributes to visibility impairment, and affects atmospheric radiative transfer, thereby contributing to global change. Vehicles contribute substantially to the ambient PM concentration in urban areas, yet the fraction of ambient PM originating from vehicle emissions is poorly characterized because suitable measurement methods have not been available. This dissertation describes the development and the use of a new vehicle emission remote sensing system (VERSS) for the on-road measurement of PM emission factors for vehicles. The PM VERSS measures PM by ultraviolet backscattering and transmission. PM backscattering and transmission mass efficiencies have been calculated from Mie theory based on an homogeneous spherical model for gasoline particles and on a two-layers, spherical model for diesel particles. The VERSS was used in a large-scale study in Las Vegas, NV. A commercial gaseous VERSS was used for the measurement of gaseous emission factors (i.e., carbon monoxide, hydrocarbons, and nitrogen oxide). Speed and acceleration were also measured for each vehicle. A video image of each vehicle's rear license plate was acquired and license plate numbers were matched with the Clark County department of motor vehicle database to retrieve vehicle information such as model year, vehicle weight category and engine ignition type. PM VERSS has precisely estimated PM fleet average emission factors and clearly shown the dependence of PM emission factors on vehicle model year. Under mostly hot-stabilized operation, diesel vehicle PM emission factors are about 25 times higher than those of gasoline vehicles. Furthermore, the fleet frequency distributions of PM emission factors are highly skewed, meaning that most of the fleet emission factor is accounted for by a small portion of the fleet. The PM VERSS can measure PM emission factors for these high emitting vehicles on an individual basis. PM

  15. Methods of and system for swing damping movement of suspended objects

    Science.gov (United States)

    Jones, J.F.; Petterson, B.J.; Strip, D.R.

    1991-03-05

    A payload suspended from a gantry is swing damped in accordance with a control algorithm based on the periodic motion of the suspended mass or by servoing on the forces induced by the suspended mass. 13 figures.

  16. Chemical Characterization and Behavior of Respirable Fractions of Indoor Dusts Collected Near a Landfill Facility

    Directory of Open Access Journals (Sweden)

    Rheo B. Lamorena-Lim

    2016-06-01

    Full Text Available The study aims to determine the inorganic and organic phases in airborne particulate matter (PM collected near a landf ill facility. The establishments within the vicinity of the landfill considered in the study were a junk shop, a school, and a money changer shop. From the elemental analysis using inductively-coupled plasma mass spectrometry (ICP-MS, lead and cadmium were discovered to be more abundant in the total suspended particulate (TSP fraction, whereas copper was more abundant in the smaller PM2.5. Manganese, arsenic, strontium, cadmium, and lead were more abundant in the PM10 fraction than in PM2.5. The results of the chemical characterization were compiled and evaluated in a geochemical modelling code (PHREEQC to determine the potential speciation of these chemical constituents. Solution complexes of As, Pb, Cd and phthalates, and metal species, such as H2AsO3- , Cd2OH3+, Pb(OH3-, were predicted to form by the PHREEQC simulation runs once the endmember components interact with water. The results contribute to the background information on the potential impacts from exposure to airborne PM at workplaces around landfill facilities. Moreover, the data gathered provide a baseline for the chemical characterization and behavior of chemical constituents of PM possibly present in this specific type of environment.

  17. Lymphocyte respiration in children with Trisomy 21

    Directory of Open Access Journals (Sweden)

    Aburawi Elhadi H

    2012-12-01

    Full Text Available Abstract Background This study measured lymphocyte mitochondrial O2 consumption (cellular respiration in children with trisomy 21. Methods Peripheral blood mononuclear cells were isolated from whole blood of trisomy 21 and control children and these cells were immediately used to measure cellular respiration rate. [O2] was determined as a function of time from the phosphorescence decay rates (1/τ of Pd (II-meso-tetra-(4-sulfonatophenyl-tetrabenzoporphyrin. In sealed vials containing lymphocytes and glucose as a respiratory substrate, [O2] declined linearly with time, confirming the zero-order kinetics of O2 conversion to H2O by cytochrome oxidase. The rate of respiration (k, in μM O2 min-1, thus, was the negative of the slope of [O2] vs. time. Cyanide inhibited O2 consumption, confirming that oxidation occurred in the mitochondrial respiratory chain. Results For control children (age = 8.8 ± 5.6 years, n = 26, the mean (± SD value of kc (in μM O2 per min per 107 cells was 1.36 ± 0.79 (coefficient of variation, Cv = 58%; median = 1.17; range = 0.60 to 3.12; -2SD = 0.61. For children with trisomy 21 (age = 7.2 ± 4.6 years, n = 26, the values of kc were 0.82 ± 0.62 (Cv = 76%; median = 0.60; range = 0.20 to 2.80, pp6.1 mU/L. Fourteen of 26 (54% children with trisomy 21 had kc values of 0.20 to 0.60 (i.e., kc positively correlated with body-mass index (BMI, R >0.302, serum creatinine (R >0.507, blood urea nitrogen (BUN, R >0.535 and albumin (R >0.446. Conclusions Children with trisomy 21 in this study have reduced lymphocyte bioenergetics. The clinical importance of this finding requires further studies.

  18. Simulation of Human Respiration with Breathing Thermal Manikin

    DEFF Research Database (Denmark)

    Bjørn, Erik

    The human respiration contains carbon dioxide, bioeffluents, and perhaps virus or bacteria. People may also indulge in activities that produce contaminants, as for example tobacco smoking. For these reasons, the human respiration remains one of the main contributors to contamination of the indoor...

  19. Interpreting diel hysteresis between soil respiration and temperature

    Science.gov (United States)

    C. Phillips; N. Nickerson; D. Risk; B.J. Bond

    2011-01-01

    Increasing use of automated soil respiration chambers in recent years has demonstrated complex diel relationships between soil respiration and temperature that are not apparent from less frequent measurements. Soil surface flux is often lagged from soil temperature by several hours, which results in semielliptical hysteresis loops when surface flux is plotted as a...

  20. Differential soil respiration responses to changing hydrologic regimes

    Science.gov (United States)

    Vincent J. Pacific; Brian L. McGlynn; Diego A. Riveros-Iregui; Howard E. Epstein; Daniel L. Welsch

    2009-01-01

    Soil respiration is tightly coupled to the hydrologic cycle (i.e., snowmelt and precipitation timing and magnitude). We examined riparian and hillslope soil respiration across a wet (2005) and a dry (2006) growing season in a subalpine catchment. When comparing the riparian zones, cumulative CO2 efflux was 33% higher, and peak efflux occurred 17 days earlier during the...

  1. Automatic patient respiration failure detection system with wireless transmission

    Science.gov (United States)

    Dimeff, J.; Pope, J. M.

    1968-01-01

    Automatic respiration failure detection system detects respiration failure in patients with a surgically implanted tracheostomy tube, and actuates an audible and/or visual alarm. The system incorporates a miniature radio transmitter so that the patient is unencumbered by wires yet can be monitored from a remote location.

  2. Soil respiration response to experimental disturbances over 3 years

    Science.gov (United States)

    Amy Concilio; Siyan Ma; Soung-Ryoul Ryu; Malcolm North; Jiquan Chen

    2006-01-01

    Soil respiration is a major pathway for carbon cycling in terrestrial ecosystems yet little is known about its response to natural and anthropogenic disturbances. This study examined soil respiration response to prescribed burning and thinning treatments in an old-growth, mixed-conifer forest on the western slope of the Sierra Nevada Mountains. Experimental treatments...

  3. Respirators: Air Purifying, Self-Study, Course 40723

    Energy Technology Data Exchange (ETDEWEB)

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

    2017-12-21

    Respirators: Air Purifying Self-Study (COURSE 40723) is designed for Los Alamos National Laboratory (LANL) workers, support services subcontractors, and other LANL subcontractors who work under the LANL Respiratory Protection Program (RPP). This course also meets the air-purifying respirators (APRs) retraining requirement.

  4. Soil Respiration and Student Inquiry: A Perfect Match

    Science.gov (United States)

    Hoyt, Catherine Marie; Wallenstein, Matthew David

    2011-01-01

    This activity explores the cycling of carbon between the atmosphere (primarily as CO[subscript 2]) and biomass in plants, animals, and microscopic organisms. Students design soil respiration experiments using a protocol that resembles current practice in soil ecology. Three methods for measuring soil respiration are presented. Student-derived…

  5. Introduction to suspended-sediment sampling

    Science.gov (United States)

    Nolan, K. Michael; Gray, John R.; Glysson, G. Douglas

    2005-01-01

    Knowledge of the amount and timing of sediment transport in streams is important to those directly or indirectly responsible for developing and managing water and land resources. Such data are often used to judge the health of watershed and the success or failure of activities designed to mitigate adverse impacts of sediment on streams and stream habitats. This training class presents an introduction to methods currently used by the U.S. Geological Survey (USGS) to sample suspended-sediment concentrations in streams. The presentation is narrated, but you control the pace of the presentation. If the computer you are using can view 'MPEG' videos you will be able to take advantage of videos interspersed in the presentation. A test, found at the end of the presentation, can be taken to assess how well you understood the training material. The class, which is registered as class SW4416 with the National Training Center of the USGS, should take two or three hours to complete. In order to use the presentation provided via this Web page, you will need to download a large disc images (linked below) and 'burn' it to a blank CD-ROM using a CD-ROM recorder on your computer. The presentation will only run on a Windows-based personal computer (PC). The presentation was developed using Macromedia Director MX 20041 and is contained in the file 'SIR05-5077.exe' which should autolaunch. If it does not, the presentation can be started by double-clicking on the file name. A sound card and speakers are necessary to take advantage of narrations that accompany the presentation. Text of narrations is provided, if you are unable to listen to narrations. Instructions for installing and running the presentation are included in the file 'Tutorial.htm', which is on the CD. 1 Registered Trademark: Macromedia Incorporated

  6. Suspended sediment drift and dispersion at Hibernia

    International Nuclear Information System (INIS)

    Tedford, T.; Drozdowski, A.; Hannah, C.G.

    2003-01-01

    Surface water waves and near-bottom currents around the Hibernia oil production platform on the Grand Banks of Newfoundland were examined to determine how the different seasons affect changes in wave magnitude and directions of water currents. Wave observations revealed a strong correlation with seasons, with the larger waves occurring in fall and early winter. There was no obvious seasonality in the size or direction of currents. The benthic boundary layer transport (BBLT) model was used to predict the drift and dispersion pathways of suspended drilling muds discharged from the Hibernia platform. The 2-year study from March 1998 to May 2000 involved 5-day BBLT model simulations covering the complete period of current meter deployment. The study focused on the sensitivity of the drift and dispersion to variability in the physical environment and uncertainty in the bottom stress calculation and particle settling velocity. The BBLT model incorporates a stress dependent particle settling velocity that includes the main features of the flocculations of drill mud fines under marine conditions. The study provides a better understanding of how drill mud concentration levels can change with variations in waves, currents, and bottom stress. It was determined that drift is generally oriented along the northwest/southeast axis, with a typical magnitude of 0.8 cm/sec for the fast settling velocity and 3.1 cm/sec for the slow settling velocity. It was concluded that near-surface or mid-depth discharges of drilling mud in the summer may not reach the sea floor. 17 refs., 13 tabs., 36 figs

  7. PIXE analysis of vehicle exhaust particulate

    International Nuclear Information System (INIS)

    Shi Xianfeng; Yao Huiying; Liu Bo; Sun Minde; Xu Huawei; Mi Yong; Shen Hao

    2001-01-01

    PIXE technique on the analysis of vehicle exhaust particulate is introduced. The clement composition and concentration of particulate are obtained. Some elements which are related to environmental pollution such as sulfur lead, silicon and manganese, were analyzed and discussed in detail by PIXE technique Nowadays although unleaded gasoline is widely used, the lead concentration is still very high in exhaust particulate. The concentrations of silicon and manganese in exhaust particulate from different model vehicles are also quite high from measurements. It shows that an evidence for exhaust pollution control could be provided from this work

  8. Respirable dust measured downwind during rock dust application.

    Science.gov (United States)

    Harris, M L; Organiscak, J; Klima, S; Perera, I E

    2017-05-01

    The Pittsburgh Mining Research Division of the U.S. National Institute for Occupational Safety and Health (NIOSH) conducted underground evaluations in an attempt to quantify respirable rock dust generation when using untreated rock dust and rock dust treated with an anticaking additive. Using personal dust monitors, these evaluations measured respirable rock dust levels arising from a flinger-type application of rock dust on rib and roof surfaces. Rock dust with a majority of the respirable component removed was also applied in NIOSH's Bruceton Experimental Mine using a bantam duster. The respirable dust measurements obtained downwind from both of these tests are presented and discussed. This testing did not measure miners' exposure to respirable coal mine dust under acceptable mining practices, but indicates the need for effective continuous administrative controls to be exercised when rock dusting to minimize the measured amount of rock dust in the sampling device.

  9. A Global Database of Soil Respiration Data, Version 1.0

    Data.gov (United States)

    National Aeronautics and Space Administration — ABSTRACT: This data set provides a soil respiration data database (SRDB), a near-universal compendium of published soil respiration (RS) data. Soil respiration, the...

  10. A Global Database of Soil Respiration Data, Version 2.0

    Data.gov (United States)

    National Aeronautics and Space Administration — ABSTRACT: This data set provides an updated soil respiration database (SRDB), a near-universal compendium of published soil respiration (RS) data. Soil respiration,...

  11. A comprehensive study of the characterization of particulate matter emissions from a Delmarva broiler poultry operation

    Science.gov (United States)

    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.

  12. Improved Methods for Correlating Turbidity and Suspended Solids for Monitoring

    National Research Council Canada - National Science Library

    2000-01-01

    This technical note describes techniques normally used to measure turbidity and suspended solids in waters, how the two parameters relate to each other and to various environmental impacts, and why...

  13. Particles matter: Transformation of suspended particles in constructed wetlands

    NARCIS (Netherlands)

    Mulling, B.T.M.

    2013-01-01

    This thesis shows that constructed wetlands transform suspended particles in (treated) municipal wastewater through selective precipitation in ponds, biological filtering by plankton communities and physical and biological retention in reed beds. These processes effectively remove faecal indicator

  14. The Ages in a Self-Suspended Nanoparticle Liquid

    KAUST Repository

    Agarwal, Praveen; Qi, Haibo; Archer, Lynden A.

    2010-01-01

    Telomers ionically tethered to nanometer-sized particles yield self-suspended, nanoparticle-Iaden liquids with unusual dynamical features. By subjecting these suspensions to controlled, modest shear strains, we find that their flow behaviors

  15. Elemental compositions of suspended particles released in glass manufacture

    Energy Technology Data Exchange (ETDEWEB)

    Mamuro, T; Mizohata, A; Kubota, T [Radiation Center of Osaka Prefecture, Sakai (Japan)

    1980-03-01

    Suspended particles released in glass manufacture were subjected to multielement analysis by means of instrumental neutron activation method and energy dispersive X-ray fluorescence spectrometry. Suspended particles emitted from glass manufacture generally consist of both particles emitted from glass fusion and those produced through fuel combustion (mainly oil combustion). Elemental compositions of suspended particles emitted from glass fusion were found to be strongly dependent on the kind and recipe of raw materials and additives. Of the various metallic elements involved in suspended particles emitted from glass fusion, the elements, As, Se, Cd, Sb, Pb and so on are regarded to produce the most serious air pollution. The amount of emission of these elements to the environment is, howerer, quite varied from manufacturer to manufacturer. The replacement of electric furnace by oil combustion in opal glass manufacture remarkably reduced the emission of metallic elements to the environment.

  16. Self-suspended permanent magnetic FePt ferrofluids

    KAUST Repository

    Dallas, Panagiotis; Kelarakis, Antonios; Sahore, Ritu; DiSalvo, Francis J.; Livi, Sebastien; Giannelis, Emmanuel P.

    2013-01-01

    on the surface of L10 FePt nanoparticles. In contrast, all types of ferrofluids previously reported employ either volatile solvents as the suspending media or superparamagnetic iron oxide nanoparticles (that lacks permanent magnetization) as the inorganic

  17. Novel Resuscitation from Lethal Hemorrhage - Suspended Animation for Delayed Resuscitation

    National Research Council Canada - National Science Library

    Safar, Peter

    2002-01-01

    .... We have conceived and documented "suspended animation for delayed resuscitation" with the use of hypothermic saline flush into the aorta within the first 5 minute of no blood flow, using novel...

  18. Evaluation of the suspending properties of Abizia zygia gum on ...

    African Journals Online (AJOL)

    Purpose: Some excipients are currently available for the formulation of pharmaceutical suspensions. ... Method: The suspending properties of Albizia zygia gum (family ... Characterization tests were carried out on purified Albizia zygia gum.

  19. Suspended sediment apportionment in a South-Korean mountain catchment

    Science.gov (United States)

    Birkholz, Axel; Meusburger, Katrin; Park, Ji-Hyung; Alewell, Christine

    2016-04-01

    Due to the rapid agricultural expansion and intensification during the last decades in South-Korea, large areas of hill slope forests were transformed to paddies and vegetable fields. The intensive agriculture and the easily erodible soils in our catchment are a major reason for the increased erosion causing suspended sediments to infiltrate into the close drinking water reservoir. The drinking water reservoir Lake Soyang provides water supply for over ten million people in Seoul. Landscape managers need to know the exact origin of these sediments before they can create landscape amelioration schemes. We applied a compound-specific stable isotope (CSSI) approach (Alewell et al., 2015) to apportion the sources of the suspended sediments between forest and agricultural soil contribution to the suspended sediments in a different catchment and applied the same approach to identify and quantify the different sources of the suspended sediments in the river(s) contributing to Lake Soyang. We sampled eight soil sites within the catchment considering the different landuse types forest, rice paddies, maize and vegetables. Suspended sediments were sampled at three outlets of the different sub-catchments. Soils and suspended sediments are analysed for bulk carbon and nitrogen isotopes, compound-specific carbon isotopes of plant-wax derived long-chain fatty acids and long-chain n-alkanes. Fatty acid and alkane isotopes are then used in mixing calculations and the mixing model software IsoSource to find out the contribution of the different source soils to the suspended sediments. We present first data of the source soils and the suspended sediments. C. Alewell, A. Birkholz, K. Meusburger, Y. Schindler-Wildhaber, L. Mabit, 2015. Sediment source attribution from multiple land use systems with CSIA. Biogeosciences Discuss. 12: 14245-14269.

  20. Airborne particulate matter in spacecraft

    Science.gov (United States)

    1988-01-01

    Acceptability limits and sampling and monitoring strategies for airborne particles in spacecraft were considered. Based on instances of eye and respiratory tract irritation reported by Shuttle flight crews, the following acceptability limits for airborne particles were recommended: for flights of 1 week or less duration (1 mg/cu m for particles less than 10 microns in aerodynamic diameter (AD) plus 1 mg/cu m for particles 10 to 100 microns in AD); and for flights greater than 1 week and up to 6 months in duration (0.2 mg/cu m for particles less than 10 microns in AD plus 0.2 mg/cu m for particles 10 to 100 microns in AD. These numerical limits were recommended to aid in spacecraft atmosphere design which should aim at particulate levels that are a low as reasonably achievable. Sampling of spacecraft atmospheres for particles should include size-fractionated samples of 0 to 10, 10 to 100, and greater than 100 micron particles for mass concentration measurement and elementary chemical analysis by nondestructive analysis techniques. Morphological and chemical analyses of single particles should also be made to aid in identifying airborne particulate sources. Air cleaning systems based on inertial collection principles and fine particle collection devices based on electrostatic precipitation and filtration should be considered for incorporation into spacecraft air circulation systems. It was also recommended that research be carried out in space in the areas of health effects and particle characterization.

  1. Dans le tourbillon des particules

    CERN Document Server

    Zito, Marco

    2015-01-01

    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...

  2. [Effects of management regime on soil respiration from agroecosystems].

    Science.gov (United States)

    Chen, Shu-tao; Zhu, Da-wei; Niu, Chuan-po; Zou, Jian-wen; Wang, Chao; Sun, Wen-juan

    2009-10-15

    In order to examine the effects of management regime, such as nitrogen application and plowing method, on soil respiration from farmland, the static opaque chamber-gas chromatograph method was used to measure soil CO2 fluxes in situ. The field measurement was carried out for 5 growing seasons, which were the 2002-2003 wheat, 2003 maize and soybean, 2003-2004 wheat, 2004 maize and 2004-2005 wheat seasons. Our results showed that soil respiration increased in fertilizer-applied treatments compared with no fertilizer treatment after 3 times of fertilizer application on 9 November 2002, 14 February and 26 March 2003. And the most obvious increase appeared following the third fertilizer application. No significant difference in soil respiration was found among several fertilizer application treatments. The effect of plowing depth on soil respiration was contingent on preceding cropping practice. Over the 2003-2004 wheat-growing seasons (its preceding cropping practice was rice paddy), mean soil respiration rates were not significant different (p > 0.05) between no plowing treatment and shallow plowing treatment. The shallow plowing treatment CT2 led to higher soil CO2 losses compared with no plowing treatment of NT2 in the 2004 maize-growing season, however, the significant higher (p soil respiration rates occurred with no plowing treatment of NT3 in the following 2004-2005 wheat-growing season. Intensive plowing (25 cm depth), compared with no plowing practice (NT4), increased soil respiration significantly during the 2004-2005 wheat-growing season. Regression analysis showed that the exponential function could be employed to fit the relationship between soil respiration and temperature. The exponential relationship yielded the Q10 values which were varied from 1.26 to 3.60, with a mean value of 2.08. To evaluate the effect of temperature on soil respiration, the CO2 emission fluxes were normalized for each treatment and each crop growing season. Plotting the

  3. Residual circulation and suspended sediment transport in the Dutch Wadden Sea

    Science.gov (United States)

    Duran-Matute, Matias; Sassi, Maximiliano; de Boer, Gerben; Grawë, Ulf; Gerkema, Theo; van Kessel, Thijs; Cronin, Katherine

    2014-05-01

    The Dutch Wadden Sea (DWS), situated between continental Europe and the Dutch Wadden Islands, is a semi enclosed basin connected to the North Sea by a series of tidal inlets and composed mainly of tidal flats and sea gullies. The DWS is of high ecological importance due to its biodiversity and has been declared a World Heritage site by UNESCO. It is a dynamic area subject to regional relative sea level rise due to global sea level rise, postglacial rebound and gas exploitation. For intertidal areas to continue to serve as feeding ground for migratory birds, a net import of sediment is required. Observations are crucial but provide only scarce information in space and time. Hence, to estimate the net influx of suspended sediment into the DWS, realistic high resolution three-dimensional numerical simulations have been carried out using the General Estuarine Transport Model (GETM). The hydrodynamics are mainly governed by the tides, the fresh water discharge from several sluices into the DWS and wind variability. It is expected that the transport of suspended particulate matter (SPM) is governed by the same factors, too, in combination with sediment sink and source terms. For validation, the results are compared against different observational data sets, such as tidal gauges, temperature and salinity at a fixed station, and the volumetric flux rate through one of the inlets obtained from an acoustic Doppler current profiler (ADCP) attached to a ferry. SPM transport is modeled for four different sediment classes each of which is defined by the critical shear stress and the settling velocity. Results show a clear net import of SPM through one of the inlets, which is in agreement with the observations. First estimates of the total sediment fluxes through the different inlets are presented together with an analysis on their variability and sensibility to the external forcing. Of particular importance is the net export of SPM during storms as well as the role of storms on

  4. Air Quality Criteria for Particulate Matter.

    Science.gov (United States)

    National Air Pollution Control Administration (DHEW), Washington, DC.

    To assist states in developing air quality standards, this book offers a review of literature related to atmospheric particulates and the development of criteria for air quality. It not only summarizes the current scientific knowledge of particulate air pollution, but points up the major deficiencies in that knowledge and the need for further…

  5. Externality costs by emission. E. Particulates

    International Nuclear Information System (INIS)

    Anon.

    1991-01-01

    Fossil-fuel-fired electricity generating systems, particularly coal and oil-fired facilities, are significant emitters of particulate matter. The major components of particulate emissions from a power plant include ash, which is made up of heavy metals, radioactive isotopes and hydrocarbons, and sulfates (SO 4 ) and nitrates (NO 3 ), which are formed by reaction of sulfur dioxide (SO 2 ) and nitrogen oxides (NO x ) in the atmosphere. The smallest ash particulates (including sulfates and nitrates) cause human respiratory effects and impaired visibility. Other effects may include materials damage due to soiling and possibly corrosion, damage to domestic and wild flora through deposition of particulates on foliage, and possible health effects on domestic animals and wild fauna. Several studies focus on the direct effects of high ambient levels of small particulates. This chapter reviews the available literature on the effects of particulate emissions on humans and their environment, and attempts to assign a cost figure to the environmental effects and human health impairments associated with particulate matter emissions. Specifically, this report focuses on the effects of particulates related to human health, visibility, flora, fauna and materials

  6. Particulate carbohydrates in the Bay of Bengal

    Digital Repository Service at National Institute of Oceanography (India)

    Bhosle, N.B.; Nandakumar, K.; Venkat, K.

    Particulate matter collected from 77 water samples over a 3000 m water column was analyzed for particulate carbohydrates (PCHO). PCHO in the surface waters ranged from 43 to 143 mu g.l-1, and below 250 m it was 16.PCHO showed large variations at all...

  7. Root Zone Respiration on Hydroponically Grown Wheat Plant Systems

    Science.gov (United States)

    Soler-Crespo, R. A.; Monje, O. A.

    2010-01-01

    Root respiration is a biological phenomenon that controls plant growth and physiological development during a plant's lifespan. This process is dependent on the availability of oxygen in the system where the plant is located. In hydroponic systems, where plants are submerged in a solution containing vital nutrients but no type of soil, the availability of oxygen arises from the dissolved oxygen concentration in the solution. This oxygen concentration is dependent on the , gas-liquid interface formed on the upper surface of the liquid, as given by Henry's Law, depending on pressure and temperature conditions. Respiration rates of the plants rise as biomass and root zone increase with age. The respiration rate of Apogee wheat plants (Triticum aestivum) was measured as a function of light intensity (catalytic for photosynthesis) and CO2 concentration to determine their effect on respiration rates. To determine their effects on respiration rate and plant growth microbial communities were introduced into the system, by Innoculum. Surfactants were introduced, simulating gray-water usage in space, as another factor to determine their effect on chemical oxygen demand of microbials and on respiration rates of the plants. It is expected to see small effects from changes in CO2 concentration or light levels, and to see root respiration decrease in an exponential manner with plant age and microbial activity.

  8. Soil Respiration in Semiarid Temperate Grasslands under Various Land Management.

    Directory of Open Access Journals (Sweden)

    Zhen Wang

    Full Text Available Soil respiration, a major component of the global carbon cycle, is significantly influenced by land management practices. Grasslands are potentially a major sink for carbon, but can also be a source. Here, we investigated the potential effect of land management (grazing, clipping, and ungrazed enclosures on soil respiration in the semiarid grassland of northern China. Our results showed the mean soil respiration was significantly higher under enclosures (2.17 μmol.m(-2.s(-1 and clipping (2.06 μmol.m(-2.s(-1 than under grazing (1.65 μmol.m-(2.s(-1 over the three growing seasons. The high rates of soil respiration under enclosure and clipping were associated with the higher belowground net primary productivity (BNPP. Our analyses indicated that soil respiration was primarily related to BNPP under grazing, to soil water content under clipping. Using structural equation models, we found that soil water content, aboveground net primary productivity (ANPP and BNPP regulated soil respiration, with soil water content as the predominant factor. Our findings highlight that management-induced changes in abiotic (soil temperature and soil water content and biotic (ANPP and BNPP factors regulate soil respiration in the semiarid temperate grassland of northern China.

  9. Soil Respiration in Semiarid Temperate Grasslands under Various Land Management.

    Science.gov (United States)

    Wang, Zhen; Ji, Lei; Hou, Xiangyang; Schellenberg, Michael P

    2016-01-01

    Soil respiration, a major component of the global carbon cycle, is significantly influenced by land management practices. Grasslands are potentially a major sink for carbon, but can also be a source. Here, we investigated the potential effect of land management (grazing, clipping, and ungrazed enclosures) on soil respiration in the semiarid grassland of northern China. Our results showed the mean soil respiration was significantly higher under enclosures (2.17 μmol.m(-2).s(-1)) and clipping (2.06 μmol.m(-2).s(-1)) than under grazing (1.65 μmol.m-(2).s(-1)) over the three growing seasons. The high rates of soil respiration under enclosure and clipping were associated with the higher belowground net primary productivity (BNPP). Our analyses indicated that soil respiration was primarily related to BNPP under grazing, to soil water content under clipping. Using structural equation models, we found that soil water content, aboveground net primary productivity (ANPP) and BNPP regulated soil respiration, with soil water content as the predominant factor. Our findings highlight that management-induced changes in abiotic (soil temperature and soil water content) and biotic (ANPP and BNPP) factors regulate soil respiration in the semiarid temperate grassland of northern China.

  10. Ferruginous compounds in the airborne particulate matter of the metropolitan area of Belo Horizonte, Minas Gerais, Brazil.

    Science.gov (United States)

    Tavares, Fernanda Vasconcelos Fonseca; Ardisson, José Domingos; Rodrigues, Paulo César Horta; Fabris, José Domingos; Fernandez-Outon, Luis Eugenio; Feliciano, Vanusa Maria Delage

    2017-08-01

    Samples of soil, iron ore, and airborne particulate matter (size airborne particulate matter in the metropolitan area of Belo Horizonte, Minas Gerais, Brazil, are either from natural origin, as, for instance, re-suspension of particles from soil, or due to anthropogenic activities, meaning that it would be originated from the many iron ore minings surrounding the metropolitan area. Numerical simulations were used to model the atmospheric dispersion of the airborne particulate matter emitted by iron mining located at the Iron Quadrangle geodomain, Minas Gerais. Results from these numerical simulations supported identifying the sites with the highest concentrations of airborne particulate matter in the metropolitan area. Samples of these suspended materials were collected at the selected sites by using high-volume air samplers. The physicochemical features of the solid materials were assessed by X-ray fluorescence, X-ray diffraction, magnetometry, and 57 Fe Mössbauer spectroscopy. The soil materials were found to be rich in quartz, aluminum, organic matter, and low contents of iron, mainly as low crystalline iron oxides. The samples of the iron ores, on the other hand, contain high concentration of iron, dominantly as relatively pure and crystalline hematite (α-Fe 2 O 3 ). The samples of the airborne particulate matter are rich in iron, mainly as hematite, but contained also quartz, aluminum, and calcium. Mössbauer spectroscopy was used to evaluate the hyperfine structure of 57 Fe of the hematite both from the iron ore and the soil samples. The structural characteristics of the hematite of these particulate materials were further explored. The direct influence of the iron ore mining on the composition of the airborne particulate matter was clearly evidenced based on the trace ability of hematite to its source of emission. Even the atmospheric air on regions relatively far away from the mining activities is also significantly influenced.

  11. Molecular Characterization of Bacterial Respiration on Minerals

    Energy Technology Data Exchange (ETDEWEB)

    Blake, Robert C.

    2013-04-26

    The overall aim of this project was to contribute to our fundamental understanding of proteins and biological processes under extreme environmental conditions. We sought to define the biochemical and physiological mechanisms that underlie biodegradative and other cellular processes in normal, extreme, and engineered environments. Toward that end, we sought to understand the substrate oxidation pathways, the electron transport mechanisms, and the modes of energy conservation employed during respiration by bacteria on soluble iron and insoluble sulfide minerals. In accordance with these general aims, the specific aims were two-fold: To identify, separate, and characterize the extracellular biomolecules necessary for aerobic respiration on iron under strongly acidic conditions; and to elucidate the molecular principles whereby these bacteria recognize and adhere to their insoluble mineral substrates under harsh environmental conditions. The results of these studies were described in a total of nineteen manuscripts. Highlights include the following: 1. The complete genome of Acidithiobacillus ferrooxidans ATCC 23270 (type strain) was sequenced in collaboration with the DOE Joint Genome Institute; 2. Genomic and mass spectrometry-based proteomic methods were used to evaluate gene expression and in situ microbial activity in a low-complexity natural acid mine drainage microbial biofilm community. This was the first effort to successfully analyze a natural community using these techniques; 3. Detailed functional and structural studies were conducted on rusticyanin, an acid-stable electron transfer protein purified from cell-free extracts of At. ferrooxidans. The three-dimensional structure of reduced rusticyanin was determined from a combination of homonuclear proton and heteronuclear 15N- and 13C-edited NMR spectra. Concomitantly, the three-dimensional structure of oxidized rusticyanin was determined by X-ray crystallography to a resolution of 1.9 A by multiwavelength

  12. Temperature response of soil respiration largely unaltered with experimental warming

    Science.gov (United States)

    Carey, Joanna C.; Tang, Jianwu; Templer, Pamela H.; Kroeger, Kevin D.; Crowther, Thomas W.; Burton, Andrew J.; Dukes, Jeffrey S.; Emmett, Bridget; Frey, Serita D.; Heskel, Mary A.; Jiang, Lifen; Machmuller, Megan B.; Mohan, Jacqueline; Panetta, Anne Marie; Reich, Peter B.; Reinsch, Sabine; Wang, Xin; Allison, Steven D.; Bamminger, Chris; Bridgham, Scott; Collins, Scott L.; de Dato, Giovanbattista; Eddy, William C.; Enquist, Brian J.; Estiarte, Marc; Harte, John; Henderson, Amanda; Johnson, Bart R.; Steenberg Larsen, Klaus; Luo, Yiqi; Marhan, Sven; Melillo, Jerry M.; Penuelas, Josep; Pfeifer-Meister, Laurel; Poll, Christian; Rastetter, Edward B.; Reinmann, Andrew B.; Reynolds, Lorien L.; Schmidt, Inger K.; Shaver, Gaius R.; Strong, Aaron L.; Suseela, Vidya; Tietema, Albert

    2016-01-01

    The respiratory release of carbon dioxide (CO2) from soil is a major yet poorly understood flux in the global carbon cycle. Climatic warming is hypothesized to increase rates of soil respiration, potentially fueling further increases in global temperatures. However, despite considerable scientific attention in recent decades, the overall response of soil respiration to anticipated climatic warming remains unclear. We synthesize the largest global dataset to date of soil respiration, moisture, and temperature measurements, totaling >3,800 observations representing 27 temperature manipulation studies, spanning nine biomes and over 2 decades of warming. Our analysis reveals no significant differences in the temperature sensitivity of soil respiration between control and warmed plots in all biomes, with the exception of deserts and boreal forests. Thus, our data provide limited evidence of acclimation of soil respiration to experimental warming in several major biome types, contrary to the results from multiple single-site studies. Moreover, across all nondesert biomes, respiration rates with and without experimental warming follow a Gaussian response, increasing with soil temperature up to a threshold of ∼25 °C, above which respiration rates decrease with further increases in temperature. This consistent decrease in temperature sensitivity at higher temperatures demonstrates that rising global temperatures may result in regionally variable responses in soil respiration, with colder climates being considerably more responsive to increased ambient temperatures compared with warmer regions. Our analysis adds a unique cross-biome perspective on the temperature response of soil respiration, information critical to improving our mechanistic understanding of how soil carbon dynamics change with climatic warming.

  13. Changes in mitochondrial respiration in the human placenta over gestation.

    Science.gov (United States)

    Holland, Olivia J; Hickey, Anthony J R; Alvsaker, Anna; Moran, Stephanie; Hedges, Christopher; Chamley, Lawrence W; Perkins, Anthony V

    2017-09-01

    Placental mitochondria are subjected to micro-environmental changes throughout gestation, in particular large variations in oxygen. How placental mitochondrial respiration adapts to changing oxygen concentrations remains unexplored. Additionally, placental tissue is often studied in culture; however, the effect of culture on placental mitochondria is unclear. Placental tissue was obtained from first trimester and term (laboured and non-laboured) pregnancies, and selectively permeabilized to access mitochondria. Respirometry was used to compare respiration states and substrate use in mitochondria. Additionally, explants of placental tissue were cultured for four, 12, 24, 48, or 96 h and respiration measured. Mitochondrial respiration decreased at 11 weeks compared to earlier gestations (p = 0.05-0.001), and mitochondrial content increased at 12-13 weeks compared to 7-10 weeks (p = 0.042). In term placentae, oxidative phosphorylation (OXPHOS) through mitochondrial complex IV (p Respiration was increased (p ≤ 0.006-0.001) in laboured compared to non-laboured placenta. After four hours of culture, respiration was depressed compared to fresh tissue from the same placenta and continued to decline with time in culture. Markers of apoptosis were increased, while markers of autophagy, mitochondrial biogenesis, and mitochondrial membrane potential were decreased after four hours of culture. Respiration and mitochondrial content alter over gestation/with labour. Decreased respiration at 11 weeks and increased mitochondrial content at 12-13 weeks may relate to onset of maternal blood flow, and increased respiration as a result of labour may be an adaptation to ischaemia-reperfusion. At term, mitochondria were more susceptible to changes in respiratory function relative to first trimester when cultured in vitro, perhaps reflecting changes in metabolic demands as gestation progresses. Metabolic plasticity of placental mitochondria has relevance to placenta

  14. Advanced Fine Particulate Characterization Methods

    Energy Technology Data Exchange (ETDEWEB)

    Steven Benson; Lingbu Kong; Alexander Azenkeng; Jason Laumb; Robert Jensen; Edwin Olson; Jill MacKenzie; A.M. Rokanuzzaman

    2007-01-31

    The characterization and control of emissions from combustion sources are of significant importance in improving local and regional air quality. Such emissions include fine particulate matter, organic carbon compounds, and NO{sub x} and SO{sub 2} gases, along with mercury and other toxic metals. This project involved four activities including Further Development of Analytical Techniques for PM{sub 10} and PM{sub 2.5} Characterization and Source Apportionment and Management, Organic Carbonaceous Particulate and Metal Speciation for Source Apportionment Studies, Quantum Modeling, and High-Potassium Carbon Production with Biomass-Coal Blending. The key accomplishments included the development of improved automated methods to characterize the inorganic and organic components particulate matter. The methods involved the use of scanning electron microscopy and x-ray microanalysis for the inorganic fraction and a combination of extractive methods combined with near-edge x-ray absorption fine structure to characterize the organic fraction. These methods have direction application for source apportionment studies of PM because they provide detailed inorganic analysis along with total organic and elemental carbon (OC/EC) quantification. Quantum modeling using density functional theory (DFT) calculations was used to further elucidate a recently developed mechanistic model for mercury speciation in coal combustion systems and interactions on activated carbon. Reaction energies, enthalpies, free energies and binding energies of Hg species to the prototype molecules were derived from the data obtained in these calculations. Bimolecular rate constants for the various elementary steps in the mechanism have been estimated using the hard-sphere collision theory approximation, and the results seem to indicate that extremely fast kinetics could be involved in these surface reactions. Activated carbon was produced from a blend of lignite coal from the Center Mine in North Dakota and

  15. Oxygen and carbon isotopic compositions of gases respired by humans

    International Nuclear Information System (INIS)

    Epstein, S.; Zeiri, L.

    1988-01-01

    Oxygen-isotope fractionation associated with respiration in human individuals at rest is linearly related to the fraction of the O 2 utilized in the respiration process. The slope of this relationship is affected by a history of smoking, by vigorous exercise, and by the N 2 /O 2 ratio of the inhaled gas. For patients who suffer anemia-related diseases, the slope of this relationship is directly proportional to their level of hemoglobin. These results introduce a new approach for studying the mechanisms of O 2 consumption in human respiration and how they are affected by related diseases

  16. Controls on Ecosystem and Root Respiration in an Alaskan Peatland

    Science.gov (United States)

    McConnell, N. A.; McGuire, A. D.; Harden, J. W.; Kane, E. S.; Turetsky, M. R.

    2010-12-01

    Boreal ecosystems cover 14% of the vegetated surface on earth and account for 25-30% of the world’s soil carbon (C), mainly due to large carbon stocks in deep peat and frozen soil layers. While peatlands have served as historical sinks of carbon, global climate change may trigger re-release of C to the atmosphere and may turn these ecosystems into net C sources. Rates of C release from a peatland are determined by regional climate and local biotic and abiotic factors such as vegetation cover, thaw depth, and peat thickness. Soil CO2 fluxes are driven by both autotrophic (plant) respiration and heterotrophic (microbial) respiration. Thus, changes in plant and microbial activity in the soil will impact CO2 emissions from peatlands. In this study, we explored environmental and vegetation controls on ecosystem respiration and root respiration in a variety of wetland sites. The study was conducted at the Alaskan Peatland Experiment (APEX; www.uoguelph.ca/APEX) sites in the Bonanza Creek Experimental Forest located 35 km southwest of Fairbanks Alaska. We measured ecosystem respiration, root respiration, and monitored a suite of environmental variables along a vegetation and soil moisture gradient including a black spruce stand with permafrost, a shrubby site with permafrost, a tussock grass site, and a herbaceous open rich fen. Within the rich fen, we have been conducting water table manipulations including a control, lowered, and raised water table treatment. In each of our sites, we measured total ecosystem respiration using static chambers and root respiration by harvesting roots from the uppermost 20 cm and placing them in a root cuvette to obtain a root flux. Ecosystem respiration (ER) on a μmol/m2/sec basis varied across sites. Water table was a significant predictor of ER at the lowered manipulation site and temperature was a strong predictor at the control site in the rich fen. Water table and temperature were both significant predictors of ER at the raised

  17. Herd protection effect of N95 respirators in healthcare workers.

    Science.gov (United States)

    Chen, Xin; Chughtai, Abrar Ahmad; MacIntyre, Chandini Raina

    2017-12-01

    Objective To determine if there was herd protection conferred to unprotected healthcare workers (HCWs) by N95 respirators worn by colleagues. Methods Data were analysed from a prospective cluster randomized clinical trial conducted in Beijing, China between 1 December 2008 and 15 January 2009. A minimum compliance level (MCL) of N95 respirators for prevention of clinical respiratory illness (CRI) was set based on various compliance cut-offs. The CRI rates were compared between compliant (≥MCL) and non-compliant (protection from use of N95 respirators by colleagues within a hospital ward.

  18. Estimating daytime ecosystem respiration from eddy-flux data

    DEFF Research Database (Denmark)

    Bruhn, Dan; Mikkelsen, Teis Nørgaard; Herbst, Mathias

    2011-01-01

    To understand what governs the patterns of net ecosystem exchange of CO2, an understanding of factors influencing the component fluxes, ecosystem respiration and gross primary production is needed. In the present paper, we introduce an alternative method for estimating daytime ecosystem respiration...... based on whole ecosystem fluxes from a linear regression of photosynthetic photon flux density data vs. daytime net ecosystem exchange data at forest ecosystem level. This method is based on the principles of the Kok-method applied at leaf level for estimating daytime respiration. We demonstrate...

  19. Thia-arenes as source apportionment tracers for urban air particulate

    International Nuclear Information System (INIS)

    McCarry, B.E.; Allan, L.M.; Mehta, S.; Marvin, C.H.

    1995-01-01

    Over sixty respirable air particulate samples were selected from a large number of filters collected in Hamilton, Ontario, Canada. Depending on the wind direction these sites were either predominantly upwind or predominantly downwind of the industrial sources. The sixty filters were extracted and analyzed using GC-MS for a range of PAH and sulfur-containing PAH (thia-arenes). Various reference standards (coal tar, diesel exhaust, urban air particulate) and source samples (coke oven condensate) were analyzed as well. A set of air particulate samples collected in another city alongside a highway provided an urban vehicular air sample. Unique thia-arene profiles were noted in the reference and source samples which provided the basis for this source apportionment work; two main approaches were used: (1) analysis of alkylated derivatives of thia-arenes with a molecular mass of 184 amu and (2) analysis of 234 amu isomers. The diesel exhaust and urban vehicular samples gave identical profiles while the coal tar and coke oven samples also had identical profiles but in different respects. The air samples collected at samplers located upwind of the coke ovens showed thia-arene profiles which were similar to the profile observed with a diesel exhaust reference material. However, air samples collected downwind of the coke ovens were heavily loaded samples and resembled the coal tar coke and oven condensate samples

  20. On Suspended matter grain size in Baltic sea

    Science.gov (United States)

    Bubnova, Ekaterina; Sivkov, Vadim; Zubarevich, Victor

    2016-04-01

    Suspended matter grain size data were gathered during the 25th research vessel "Akademik Mstislav Keldysh" cruise (1991, September-October). Initial quantitative data were obtained with a use of the Coulter counter and subsequently modified into volume concentrations (mm3/l) for size intervals. More than 80 samples from 15 stations were analyzed (depth range 0-355 m). The main goal of research was to illustrate the spatial variability of suspended matter concentration and dispersion in Baltic Sea. The mutual feature of suspended matter grain size distribution is the logical rise of particle number along with descending of particle's size. Vertical variability of grain size distribution was defined by Baltic Sea hydrological structure, including upper mixed layer - from the surface to the thermocline - with 35 m thick, cold intermediate layer - from the thermocline to the halocline- and bottom layer, which lied under the halocline. Upper layer showed a rise in total suspended matter concentration (up to 0.6 mm3/l), while cold intermediate level consisted of far more clear water (up to 0.1 mm3/l). Such a difference is caused by the thermocline boarding role. Meanwhile, deep bottom water experienced surges in suspended matter concentration owing to the nepheloid layer presence and "liquid bottom" effect. Coastal waters appeared to have the highest amount of particles (up to 5.0 mm3/l). Suspended matter grain size distribution in the upper mixed layer revealed a peak of concentration at 7 μ, which can be due to autumn plankton bloom. Another feature in suspended matter grain size distribution appeared at the deep layer below halocline, where both O2 and H2S were observed and red/ox barrier is. The simultaneous presence of Fe and Mn (in solutions below red/ox barrier) and O2 leads to precipitation of oxyhydrates Fe and Mn and grain size distribution graph peaking at 4.5 μ.

  1. Particulate filtration in nuclear facilities

    International Nuclear Information System (INIS)

    1991-01-01

    The removal of particulate radioactive material from exhaust air or gases is an essential feature of virtually all nuclear facilities. Recent IAEA publications have covered the broad designs of off-gas and air cleaning systems for the range of nuclear power plants and other facilities. This report is a complementary guidebook that examines in detail the latest developments in the design, operation, maintenance and testing of fibrous air filters. The original draft of the report was prepared by three consultants, M.W. First, of the School of Public Health, Harvard University, United States of America, K.S. Robinson, from the UKAEA Harwell Laboratory, United Kingdom, and H.G. Dillmann, of the Kernforschungzentrum, Karlsruhe, Germany. The Technical Committee Meeting (TCM), at which the report was reviewed and much additional information contributed, was attended by 11 experts and was held in Vienna, from 30 May to 3 June 1988. 64 refs, 41 figs, 10 tabs

  2. Radiant zone heated particulate filter

    Science.gov (United States)

    Gonze, Eugene V [Pinckney, MI

    2011-12-27

    A system includes a particulate matter (PM) filter including an upstream end for receiving exhaust gas and a downstream end. A radiant zoned heater includes N zones, where N is an integer greater than one, wherein each of the N zones includes M sub-zones, where M is an integer greater than or equal to one. A control module selectively activates at least a selected one of the N zones to initiate regeneration in downstream portions of the PM filter from the one of the N zones, restricts exhaust gas flow in a portion of the PM filter that corresponds to the selected one of the N zones, and deactivates non-selected ones of the N zones.

  3. Occupational Exposure to Respirable Dust, Respirable Crystalline Silica and Diesel Engine Exhaust Emissions in the London Tunnelling Environment.

    Science.gov (United States)

    Galea, Karen S; Mair, Craig; Alexander, Carla; de Vocht, Frank; van Tongeren, Martie

    2016-03-01

    Personal 8-h shift exposure to respirable dust, diesel engine exhaust emissions (DEEE) (as respirable elemental carbon), and respirable crystalline silica of workers involved in constructing an underground metro railway tunnel was assessed. Black carbon (BC) concentrations were also assessed using a MicroAeth AE51. During sprayed concrete lining (SCL) activities in the tunnel, the geometric mean (GM) respirable dust exposure level was 0.91mg m(-3), with the highest exposure measured on a back-up sprayer (3.20mg m(-3)). The GM respirable crystalline silica concentration for SCL workers was 0.03mg m(-3), with the highest measurement also for the back-up sprayer (0.24mg m(-3)). During tunnel boring machine (TBM) activities, the GM respirable dust concentration was 0.54mg m(-3). The GM respirable elemental carbon concentration for all the TBM operators was 18 µg m(-3); with the highest concentration measured on a segment lifter. The BC concentrations were higher in the SCL environment in comparison to the TBM environment (daily GM 18-54 µg m(-3) versus 3-6 µg m(-3)). This small-scale monitoring campaign provides additional personal data on exposures experienced by underground tunnel construction workers. © The Author 2015. Published by Oxford University Press on behalf of the British Occupational Hygiene Society.

  4. Respiration in heterotrophic unicellular eukaryotic organisms.

    Science.gov (United States)

    Fenchel, Tom

    2014-08-01

    Surface:volume quotient, mitochondrial volume fraction, and their distribution within cells were investigated and oxygen gradients within and outside cells were modelled. Cell surface increases allometrically with cell size. Mitochondrial volume fraction is invariant with cell size and constitutes 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-tensions. Available data do not contradict this and some evidence supports this interpretation. Cell size is ultimately limited because an increasing fraction of the mitochondria becomes exposed to near anoxic conditions with increasing cell size. The fact that mitochondria cluster close to the cell surface and the allometric change in cell shape with increasing cell size alleviates the limitation of aerobic life at low ambient O2-tension and for large cell size. Copyright © 2014 Elsevier GmbH. All rights reserved.

  5. Assessment of suspended particulate matters and their heavy metal content in the ambient air of Mobarakeh city, Isfahan, Iran

    Directory of Open Access Journals (Sweden)

    Avazali Saririan Mobarakeh

    2014-01-01

    Conclusion: This study showed that ambient air of Mobarakeh city is polluted by TSP. The high concentration of Fe and Ni in this area may be attributed to the nearby industrial emissions. Therefore, in industrial areas, efforts should be taken to control the atmospheric pollution in order to protect humans from hazardous health effects of these potentially toxic pollutants.

  6. Physical and chemical characterization of the particulate matter suspended in aerosols from the urban area of Belgrade

    Directory of Open Access Journals (Sweden)

    JASMINKA D. JOKSIĆ

    2009-11-01

    Full Text Available In the pharmaceutical industry, an important step consists in the removal of possible drug residues from the involved equipments and areas. The cleaning procedures must be validated and methods to determine trace amounts of drugs have, therefore, to be considered with special attention. An HPLC–UV method for the determination of digoxin residues on stainless steel surfaces was developed and validated in order to control a cleaning procedure. Cotton swabs, moistened with methanol were used to remove any residues of drugs from stainless steel surfaces, and give recoveries of 85.9, 85.2 and 78.7 % for three concentration levels. The precision of the results, reported as the relative standard deviation (RSD, were below 6.3 %. The method was validated over a concentration range of 0.05–12.5 µg mL-1. Low quantities of drug residues were determined by HPLC–UV using a Symmetry C18 column (150´4.6 mm, 5 µm at 20 °C with an acetonitrile–water (28:72, v/v mobile phase at a flow rate of 1.1 mL min-1, an injection volume of 100 µL and were detected at 220 nm. A simple, selective and sensitive HPLC–UV assay for the determination of digoxin residues on stainless steel was developed, validated and applied.

  7. 40 CFR Appendix B to Part 50 - Reference Method for the Determination of Suspended Particulate Matter in the Atmosphere (High...

    Science.gov (United States)

    2010-07-01

    ... analysis. Quality assurance procedures and guidance are provided in part 58, appendixes A and B, of this..., and shall be mounted so as to form an air inlet gap between the cover and the sampler housing walls...-600/9-76-005, U.S. Environmental Protection Agency, Research Triangle Park, NC 27711, 1976. 2. Quality...

  8. Carbon and nitrogen isotopic composition of suspended particulate organic matter in Zuari Estuary, west coast of India

    Digital Repository Service at National Institute of Oceanography (India)

    Bardhan, P.; Karapurkar, S.G.; Shenoy, D.M.; Kurian, S.; Sarkar, A.; Maya, M.V.; Naik, H.; Varik, S.; Naqvi, S.W.A.

    participates in riverine delivery of bioavailable nitrogen to coastal zones. Global Biogeochemical Cycles 12(4), 573-579. 30. Naqvi, S. W. A., Jayakumar, D. A., Narvekar, P. V., Naik, H., Sarma, V. V. S. S., D'souza, W., Joseph,S. George, M. D. (2000...

  9. 78 FR 22425 - Designation of Areas for Air Quality Planning Purposes; State of Nevada; Total Suspended Particulate

    Science.gov (United States)

    2013-04-16

    ... Valley, Fernley Area, Mason Valley, and Clovers Area. EPA is taking this action under the Clean Air Act... Reese Valley, Fernley Area, Mason Valley, and Clovers Area III. Final Action and Request for Comment IV... Reese Valley (HA 59), Gabbs Valley (HA 122), Fernley Area (HA 76), Truckee Meadows (HA 87), Mason Valley...

  10. Dispersal and sink pathways of suspended particulate matter from the orographically enhanced SWM regime of the SE Arabian Sea

    Digital Repository Service at National Institute of Oceanography (India)

    Chauhan, O.S.; Kader, U.S.A.; Vaidya, P.; Rajawat, A.S.; Ajai; Ramakrishnan, R.

    during NE monsoon. Deep-Sea Research part II, 52(14-15), pp. 2018-2030. doi:10.1016/j.dsr2.2005.05.012 CHAUHAN, O. S., VOGELSANG, E., BASAVAIAH, N. and KADER, U. S. A., 2010, Reconstruction of the variability of the southwest monsoon during the past...

  11. Spatial distribution of suspended particulate matter in the Mandovi and Zuari estuaries: inferences on the estuarine turbidity maximum

    Digital Repository Service at National Institute of Oceanography (India)

    Suja, S.; Kessarkar, P.M.; Shynu, R.; Rao, V.P.; Fernandes, L.L.

    to tidal and wind-driven waves and currents. Our results corroborate the findings of Kes- sarkar et al.10,16 that high ETM is associ- ated with high salinity at the sea end. The vertical profiles of SPM suggest ex- tension of this ETM up to 2 m depth... instantaneously forming a high-temperature mineral phase (fayalite) along with a quenched glassy matrix. Studies on ancient slags worldwide7–10 have shown that the proportions of phos- phorus are in the range 0.05–0.5 wt%, with levels up to 1.0 wt...

  12. 40 CFR Appendix G to Part 50 - Reference Method for the Determination of Lead in Suspended Particulate Matter Collected From...

    Science.gov (United States)

    2010-07-01

    ... minimize the possibility of generating unreliable data, the user should follow practices established for... chapter—Modifications of methods by users. (Guidance or assistance in requesting approval under Section 2... lead content of the sample is analyzed by atomic absorption spectrometry using an air-acetylene flame...

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

    DEFF Research Database (Denmark)

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

    2014-01-01

    (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......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...

  14. Size-Selective Sampling Performance of Six Low-Volume “Total” Suspended Particulate (TSP) Inlets

    Data.gov (United States)

    U.S. Environmental Protection Agency — Results from the comprehensive wind tunnel evaluation of six low-volume aerosol inlets are presented as a function of wind speed and aerodynamic particle diameter....

  15. Trends of particulate matter in four cities in India

    Science.gov (United States)

    Gupta, Indrani; Kumar, Rakesh

    Particulate matter (PM) in all the four Metropolitan cities in India are higher than the prescribed standards of Central Pollution Control Board, India as well as WHO guidelines. Over last 10 years various changes in fuel quality, vehicle technologies, industrial fuel mix and domestic fuel mix have taken place resulting in changes in air quality in these cities. A set of time series analysis methods viz. t-test adjusted for seasonality, Seasonal Kendall test and Intervention analysis have been applied to identify and estimate the trend in PM 10 and total suspended particles (TSP) levels monitored for about 10 years at three monitoring sites at each of the four cities in India. These tests have indicated that overall PM 10 levels in all four metro cities have been decreasing or stationary. The distinct trends for the monthly averages of PM 10 concentrations at Parel, Kalbadevi in Mumbai and Thiruvattiyar in Chennai for the period 1993-2003 were declining by 10%, 6% and 5% per annum, respectively. This is ascribed to a shift in the magnitude and spatial distribution of emissions in the city. However, the monthly averages of TSP do not have a clear trend over the period 1991-2003.

  16. Role of particulates in subsurface migration of wastes

    International Nuclear Information System (INIS)

    Eichholz, G.G.; Craft, T.F.

    1982-01-01

    In contrast to the usual assumption that migration of radioactive wastes from deep repositories will occur primarily in the form of dissolved ions, subject to control by ion-exchange phenomena on exposed surfaces, an alternative mode of migration has been investigated by way of submicron-size suspended particles that act as carriers for leached waste atoms and travel relatively freely through water-bearing strata. Measurements have been conducted on adsorption on kaolin of Pu, Tc, Cs, Np and other tracer ions, with results strongly dependent on the nature of the water and its pH. Independently, column tests have been performed to study the movement of labelled kaolin suspensions through beds of sand, basalt, limestone and shale. For each medium, filter coefficients and sorption coefficients have been determined. For some bed materials the effluent suspensions displayed a prompt and a delayed component; the nature of the delay mechanism is not clearly understood at present. The investigations have shown that under certain conditions particulate migration may constitute a competitive pathway for waste motion. (author)

  17. [Exploration of a quantitative methodology to characterize the retention of PM2.5 and other atmospheric particulate matter by plant leaves: taking Populus tomentosa as an example].

    Science.gov (United States)

    Zhang, Zhi-Dan; Xi, Ben-Ye; Cao, Zhi-Guo; Jia, Li-Ming

    2014-08-01

    Taking Populus tomentosa as an example, a methodology called elution-weighing-particle size-analysis (EWPA) was proposed to evaluate quantitatively the ability of retaining fine particulate matter (PM2.5, diameter d ≤ 2.5 μm) and atmospheric particulate matter by plant leaves using laser particle size analyzer and balance. This method achieved a direct, accurate measurement with superior operability about the quality and particle size distribution of atmospheric particulate matter retained by plant leaves. First, a pre-experiment was taken to test the stability of the method. After cleaning, centrifugation and drying, the particulate matter was collected and weighed, and then its particle size distribution was analyzed by laser particle size analyzer. Finally, the mass of particulate matter retained by unit area of leaf and stand was translated from the leaf area and leaf area index. This method was applied to a P. tomentosa stand which had not experienced rain for 27 days in Beijing Olympic Forest Park. The results showed that the average particle size of the atmospheric particulate matter retained by P. tomentosa was 17.8 μm, and the volume percentages of the retained PM2.5, inhalable particulate matter (PM10, d ≤ 10 μm) and total suspended particle (TSP, d ≤ 100 μm) were 13.7%, 47.2%, and 99.9%, respectively. The masses of PM2.5, PM10, TSP and total particulate matter were 8.88 x 10(-6), 30.6 x 10(-6), 64.7 x 10(-6) and 64.8 x 10(-6) g x cm(-2) respectively. The retention quantities of PM2.5, PM10, TSP and total particulate matter by the P. tomentosa stand were 0.963, 3.32, 7.01 and 7.02 kg x hm(-2), respectively.

  18. Temperature signal in suspended sediment export from an Alpine catchment

    Science.gov (United States)

    Costa, Anna; Molnar, Peter; Stutenbecker, Laura; Bakker, Maarten; Silva, Tiago A.; Schlunegger, Fritz; Lane, Stuart N.; Loizeau, Jean-Luc; Girardclos, Stéphanie

    2018-01-01

    Suspended sediment export from large Alpine catchments ( > 1000 km2) over decadal timescales is sensitive to a number of factors, including long-term variations in climate, the activation-deactivation of different sediment sources (proglacial areas, hillslopes, etc.), transport through the fluvial system, and potential anthropogenic impacts on the sediment flux (e.g. through impoundments and flow regulation). Here, we report on a marked increase in suspended sediment concentrations observed near the outlet of the upper Rhône River Basin in the mid-1980s. This increase coincides with a statistically significant step-like increase in basin-wide mean air temperature. We explore the possible explanations of the suspended sediment rise in terms of changes in water discharge (transport capacity), and the activation of different potential sources of fine sediment (sediment supply) in the catchment by hydroclimatic forcing. Time series of precipitation and temperature-driven snowmelt, snow cover, and ice melt simulated with a spatially distributed degree-day model, together with erosive rainfall on snow-free surfaces, are tested to explore possible reasons for the rise in suspended sediment concentration. We show that the abrupt change in air temperature reduced snow cover and the contribution of snowmelt, and enhanced ice melt. The results of statistical tests show that the onset of increased ice melt was likely to play a dominant role in the suspended sediment concentration rise in the mid-1980s. Temperature-driven enhanced melting of glaciers, which cover about 10 % of the catchment surface, can increase suspended sediment yields through an increased contribution of sediment-rich glacial meltwater, increased sediment availability due to glacier recession, and increased runoff from sediment-rich proglacial areas. The reduced extent and duration of snow cover in the catchment are also potential contributors to the rise in suspended sediment concentration through

  19. Proton-induced X-ray emission analysis of marine particulates

    International Nuclear Information System (INIS)

    Burnett, W.C.; Mitchum, G.T.

    1981-01-01

    We report a methodology used to analyze suspended marine particulates by particle induced X-ray emission (PIXE). Water samples from an estuary in Brazil were filtered soon after collection onto pre-weighed Nuclepore filters, washed with deionized water, dried to constant weight and analyzed as thin targets. Because of the relatively high mass loadings (0.1-1.0 mg/cm 2 ) on the filters, proton bombardment times of a few minutes were adequate for maintaining good counting statistics. Precision and accuary were determined by replicate analysis and intercomparison to geochemical standards. Suspensions of standards in deionized water were filtered dried, weighed and analyzed in a similar fashion as our samples of marine particulates. Net X-ray intensities were related to mass by calibration against pure elemental standards. Initial experiments showed systematically low concentrations for all elements determined by PIXE relative to known values. Further experiments verified that this systematic errors was due to an uneven distribution of mass on the surface of the filters. Improvements in the filtration technique have eliminated the topographic effect on our samples and the PIXE resultes were substantially improved. Variations in matrix and particle size of the samples analyzed did not cause any measureable analytical effect. PIXE thus seems well suited for providing rapid, multi-element data on samples of marine particulates if suitable precautions are made during the sample preparation process. (orig.)

  20. Air particulate pollution studies in Asian countries using nuclear analytical techniques

    International Nuclear Information System (INIS)

    Hien, P.D.

    1998-01-01

    Air particulate pollution is regarded as critical in Asian cities. The levels of suspended particulate matter in major Asian cities far exceed the WHO's guideline. Nuclear analytical techniques have been widely used in the studies of air particulate pollution to provide aerosol elemental compositions for the purpose of deriving the structure of emission sources. This paper presents some preliminary observations and findings based on publications in scientific literatures. Data on PM-10 levels and socio-economic indicators are used for searching a relationship between air quality and the level of development across Asia. An inverse linear relationship between PM-10 levels and logarithm of per capita GDP appears to exist, although there are large fluctuations of data caused by the very different climatic and geographical conditions of cities studied. Soil dust is generally a major, or even predominant aerosol source in Asian cities. Other common sources include vehicular emissions, coal and oil combustion, burning of refuse (in open) and biomass (including forest fires). The relevance and the trends of these sources in Asian context are discussed. Multivariate receptor modelling techniques applied in source characterization are illustrated through the cases of Lahore and Hochiminh City. Although having limitations in dealing with mixing and overlapping sources, receptor modelling based on principal component factor analysis has been proven to be uncomplicated and sufficiently reliable for characterising aerosol sources in urban areas. (author)

  1. Origin and Distribution of PAHs in Ambient Particulate Samples at High Mountain Region in Southern China

    Directory of Open Access Journals (Sweden)

    Peng-hui Li

    2015-01-01

    Full Text Available To understand the deposition and transport of PAHs in southern China, a measurement campaign was conducted at a high-elevation site (the summit of Mount Heng, 1269 m A.S.L. from April 4 to May 31, 2009, and a total of 39 total suspended particulate samples were collected for measurement of PAH concentrations. The observed particulate-bound PAHs concentrations ranged from 1.63 to 29.83 ng/m3, with a mean concentration of 6.03 ng/m3. BbF, FLA, and PYR were the predominant compounds. Good correlations were found between individual PAHs and meteorological parameters such as atmospheric pressure, relative humidity, and ambient temperature. The backward trajectory analysis suggested that particulate samples measured at the Mount Heng region were predominantly associated with the air masses from southern China, while the air masses transported over northern and northwestern China had relative higher PAHs concentrations. Based on the diagnostic ratios and factor analysis, vehicular emission, coal combustion, industry emission, and unburned fossil fuels were suggested to be the PAHs sources at Mount Heng site. However, the reactivity and degradation of individual PAHs could influence the results of PAH source profiles, which deserves further investigations in the future.

  2. Contribution of root to soil respiration and carbon balance in ...

    Indian Academy of Sciences (India)

    PRAKASH

    improves our understanding of the terrestrial carbon cycle ... considerably lower net ecosystem productivity in Community 2 than in Community 1 .... soil respiration chambers for each time were dried at 31ºC ..... Using existing management.

  3. Redefinition and global estimation of basal ecosystem respiration rate

    Energy Technology Data Exchange (ETDEWEB)

    Yuan, Wenping [College of Global Change and Earth System Science, Beijing Normal University, Beijing, China; Luo, Yiqi [Department of Botany and Microbiology, University of Oklahoma, Norman, Oklahoma, USA; Li, Xianglan [College of Global Change and Earth System Science, Beijing Normal University, Beijing, China; Liu, Shuguang; Yu, Guirui [Key Laboratory of Ecosystem Network Observation and Modeling, Synthesis Research Center of Chinese Ecosystem Research Network, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China; Zhou, Tao [State Key Laboratory of Earth Surface Processes and Resource Ecology, Beijing Normal University, Beijing, China; Bahn, Michael [Institute of Ecology, University of Innsbruck, Innsbruck, Austria; Black, Andy [Faculty of Land and Food Systems, University of British Columbia, Vancouver, B. C., Canada; Desai, Ankur R. [Atmospheric and Oceanic Sciences Department, Center for Climatic Research, Nelson Institute for Environmental Studies, University of Wisconsin-Madison, Madison, Wisconsin, USA; Cescatti, Alessandro [Institute for Environment and Sustainability, Joint Research Centre, European Commission, Ispra, Italy; Marcolla, Barbara [Sustainable Agro-ecosystems and Bioresources Department, Fondazione Edmund Mach-IASMA Research and Innovation Centre, San Michele all' Adige, Italy; Jacobs, Cor [Alterra, Earth System Science-Climate Change, Wageningen University, Wageningen, Netherlands; Chen, Jiquan [Department of Earth, Ecological, and Environmental Sciences, University of Toledo, Toledo, Ohio, USA; Aurela, Mika [Climate and Global Change Research, Finnish Meteorological Institute, Helsinki, Finland; Bernhofer, Christian [Chair of Meteorology, Institute of Hydrology and Meteorology, Technische Universität Dresden, Dresden, Germany; Gielen, Bert [Department of Biology, University of Antwerp, Wilrijk, Belgium; Bohrer, Gil [Department of Civil, Environmental, and Geodetic Engineering, Ohio State University, Columbus, Ohio, USA; Cook, David R. [Climate Research Section, Environmental Science Division, Argonne National Laboratory, Argonne, Illinois, USA; Dragoni, Danilo [Department of Geography, Indiana University, Bloomington, Indiana, USA; Dunn, Allison L. [Department of Physical and Earth Sciences, Worcester State College, Worcester, Massachusetts, USA; Gianelle, Damiano [Sustainable Agro-ecosystems and Bioresources Department, Fondazione Edmund Mach-IASMA Research and Innovation Centre, San Michele all' Adige, Italy; Grünwald, Thomas [Chair of Meteorology, Institute of Hydrology and Meteorology, Technische Universität Dresden, Dresden, Germany; Ibrom, Andreas [Risø DTU National Laboratory for Sustainable Energy, Biosystems Division, Technical University of Denmark, Roskilde, Denmark; Leclerc, Monique Y. [Department of Crop and Soil Sciences, College of Agricultural and Environmental Sciences, University of Georgia, Griffin, Georgia, USA; Lindroth, Anders [Geobiosphere Science Centre, Physical Geography and Ecosystems Analysis, Lund University, Lund, Sweden; Liu, Heping [Laboratory for Atmospheric Research, Department of Civil and Environmental Engineering, Washington State University, Pullman, Washington, USA; Marchesini, Luca Belelli [Department for Innovation in Biological, Agro-Food and Forest Systems, University of Tuscia, Viterbo, Italy; Montagnani, Leonardo; Pita, Gabriel [Department of Mechanical Engineering, Instituto Superior Técnico, Lisbon, Portugal; Rodeghiero, Mirco [Sustainable Agro-ecosystems and Bioresources Department, Fondazione Edmund Mach-IASMA Research and Innovation Centre, San Michele all' Adige, Italy; Rodrigues, Abel [Unidade de Silvicultura e Produtos Florestais, Instituto Nacional dos Recursos Biológicos, Oeiras, Portugal; Starr, Gregory [Department of Biological Sciences, University of Alabama, Tuscaloosa, Alabama, USA; Stoy, Paul C. [Department of Land Resources and Environmental Sciences, Montana State University, Bozeman, Montana, USA

    2011-10-13

    Basal ecosystem respiration rate (BR), the ecosystem respiration rate at a given temperature, is a common and important parameter in empirical models for quantifying ecosystem respiration (ER) globally. Numerous studies have indicated that BR varies in space. However, many empirical ER models still use a global constant BR largely due to the lack of a functional description for BR. In this study, we redefined BR to be ecosystem respiration rate at the mean annual temperature. To test the validity of this concept, we conducted a synthesis analysis using 276 site-years of eddy covariance data, from 79 research sites located at latitudes ranging from ~3°S to ~70°N. Results showed that mean annual ER rate closely matches ER rate at mean annual temperature. Incorporation of site-specific BR into global ER model substantially improved simulated ER compared to an invariant BR at all sites. These results confirm that ER at the mean annual

  4. Temperature response of soil respiration largely unaltered with experimental warming

    DEFF Research Database (Denmark)

    Carey, Joanna C; Tang, Jianwu; Templer, Pamela H

    2016-01-01

    The respiratory release of carbon dioxide (CO2) from soil is a major yet poorly understood flux in the global carbon cycle. Climatic warming is hypothesized to increase rates of soil respiration, potentially fueling further increases in global temperatures. However, despite considerable scientific...... attention in recent decades, the overall response of soil respiration to anticipated climatic warming remains unclear. We synthesize the largest global dataset to date of soil respiration, moisture, and temperature measurements, totaling >3,800 observations representing 27 temperature manipulation studies......, spanning nine biomes and over 2 decades of warming. Our analysis reveals no significant differences in the temperature sensitivity of soil respiration between control and warmed plots in all biomes, with the exception of deserts and boreal forests. Thus, our data provide limited evidence of acclimation...

  5. respiration and transpiration characteristics of selected fresh fruits

    African Journals Online (AJOL)

    AISA

    were higher in optimal atmospheres. The Q10 values ... High respiration rates increase tissue aging and decrease the ability of the product to repel ... Two types of containers were used for the ..... availability of oxygen around the product also.

  6. Evaluation of particulate filtration efficiency of retrofit particulate filters for light duty vehicles

    International Nuclear Information System (INIS)

    Van Asch, R.; Verbeek, R.

    2009-10-01

    In the light of the currently running subsidy programme for particulate filters in the Netherlands, the Dutch ministry of spatial planning and environment (VROM) asked TNO to execute a desk study to evaluate the particulates filtration efficiency of retrofit particulate filters for light duty vehicles (passenger cars and vans). The typical retrofit particulate filters for light duty vehicles are also called 'open' or 'half-open' filters, because a part of the exhaust gas can pass through the particulate filter unfiltered. From design point they are very different from the majority of the factory installed particulate filters, which are also called wall-flow or 'closed' particulate filters. Due to these differences there is a large difference in filtration efficiency. Whereas the 'dosed' particulate filters show a filtration efficiency of larger than 90%, the filtration efficiency of 'open' particulate filters is generally lower (type approval minimum 30%), and strongly dependent on the conditions of use. The objective of the current project was to assess the average filtration efficiency of retrofit (open) particulate fillters on light duty vehicles in real world day to day driving, based on available literature data. Also, the reasons of a possible deviation with the type approval test results (minimum filtration efficiency of 30%) was investigated.

  7. Tai Chi training reduced coupling between respiration and postural control.

    Science.gov (United States)

    Holmes, Matthew L; Manor, Brad; Hsieh, Wan-hsin; Hu, Kun; Lipsitz, Lewis A; Li, Li

    2016-01-01

    In order to maintain stable upright stance, the postural control system must account for the continuous perturbations to the body's center-of-mass including those caused by spontaneous respiration. Both aging and disease increase "posturo-respiratory synchronization;" which reflects the degree to which respiration affects postural sway fluctuations over time. Tai Chi training emphasizes the coordination of respiration and bodily movements and may therefore optimize the functional interaction between these two systems. The purpose of the project was to examine the effect of Tai Chi training on the interaction between respiration and postural control in older adults. We hypothesized that Tai Chi training would improve the ability of the postural control system to compensate for respiratory perturbations and thus, reduce posturo-respiratory synchronization. Participants were recruited from supportive housing facilities and randomized to a 12-week Tai Chi intervention (n=28; 86 ± 5 yrs) or educational-control program (n=34, 85 ± 6 yrs). Standing postural sway and respiration were simultaneously recorded with a force plate and respiratory belt under eyes-open and eyes-closed conditions. Posturo-respiratory synchronization was determined by quantifying the variation of the phase relationship between the dominant oscillatory mode of respiration and corresponding oscillations within postural sway. Groups were similar in age, gender distribution, height, body mass, and intervention compliance. Neither intervention altered average sway speed, sway magnitude or respiratory rate. As compared to the education-control group, however, Tai Chi training reduced posturo-respiratory synchronization when standing with eyes open or closed (ppostural control or respiration, yet reduced the coupling between respiration and postural control. The beneficial effects of Tai Chi training may therefore stem in part from optimization of this multi-system interaction. Copyright © 2015

  8. Carbon dioxide titration method for soil respiration measurements

    OpenAIRE

    Martín Rubio, Luis

    2017-01-01

    This thesis was commissioned by Tampere University of Applied Sciences, which was interested in studying and developing a titration measurement method for soil respiration and biodegradability. Some experiments were carried out measuring soil respiration for testing the method and others adding some biodegradable material like polylactic acid compressed material and 100% biodegradable plastic bags to test its biodegradability and the possibility to measure it via titration. The thesi...

  9. Fuzzy Control of Tidal volume, Respiration number and Pressure value

    OpenAIRE

    Hasan Guler; Fikret Ata

    2010-01-01

    In this study, control of tidal volume, respiration number and pressure value which are arrived to patient at mechanical ventilator device which is used in intensive care units were performed with fuzzy logic controller. The aim of this system is to reduce workload of aneshesiologist. By calculating tidal volume, respiration number and pressure value, the error Pe(k) between reference pressure value (Pref) and pressure of gas given ill person (Phasta) and error change rate ;#948;Pe(k) were co...

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

    Science.gov (United States)

    Kiko, R.; Hauss, H.; Buchholz, F.; Melzner, F.

    2015-10-01

    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 considerably fuels bacterial anaerobic ammonium oxidation - a major loss process for fixed nitrogen in the ocean. These estimates were based on the implicit assumption that hypoxia or anoxia in combination with hypercapnia (elevated pCO2) does not result in a downregulation of ammonium excretion. Here we show that exposure to OMZ conditions can result in strong depression of respiration and ammonium excretion in calanoid copepods and euphausiids from the Eastern Tropical North Atlantic and the Eastern Tropical South Pacific. These physiological responses need to be taken into account when estimating DVM-mediated fluxes of carbon and nitrogen into OMZs.

  11. Use of respirators for protection of workers against airborne radioactive materials

    International Nuclear Information System (INIS)

    Revoir, W.H.

    1990-01-01

    The various types of respirators and the requirements for an effective respirator program are outlined. The use of specific types of respirators to protect workers against inhalation of airborne radioactive materials is discussed. Problems encountered in using respirators in the nuclear industry which have resulted in worker injury and death are described

  12. Particulate matter over a seven year period in urban and rural areas within, proximal and far from mining and power station operations in Greece.

    Science.gov (United States)

    Triantafyllou, A G; Zoras, S; Evagelopoulos, V

    2006-11-01

    Lignite mining operations and lignite-fired power stations result in major particulate pollution (fly ash and fugitive dust) problems in the areas surrounding these activities. The problem is more complicated, especially, for urban areas located not far from these activities, due to additional contribution from the urban pollution sources. Knowledge of the distribution of airborne particulate matter into size fraction has become an increasing area of focus when examining the effects of particulate pollution. On the other hand, airborne particle concentration measurements are useful in order to assess the air pollution levels based on national and international air quality standards. These measurements are also necessary for developing air pollutants control strategies or for evaluating the effectiveness of these strategies, especially, for long periods. In this study an attempt is made in order to investigate the particle size distribution of fly ash and fugitive dust in a heavy industrialized (mining and power stations operations) area with complex terrain in the northwestern part of Greece. Parallel total suspended particulates (TSP) and particulate matter with an aerodynamic diameter less than 10 microm (PM10) concentrations are analyzed. These measurements gathered from thirteen monitoring stations located in the greater area of interest. Spatial, temporal variation and trend are analyzed over the last seven years. Furthermore, the geographical variation of PM10 - TSP correlation and PM10/TSP ratio are investigated and compared to those in the literature. The analysis has indicated that a complex system of sources and meteorological conditions modulate the particulate pollution of the examined area.

  13. Stimulation of respiration in rat thymocytes induced by ionizing radiation

    International Nuclear Information System (INIS)

    Gudz, T.I.; Pandelova, I.G.; Novgorodov, S.A.

    1994-01-01

    The effect of X irradiation on the respiration of rat thymocytes was studied. An increase in the rate of O 2 uptake was observed 1 h after cells were irradiated with doses of 6-10 Gy. The radiation-induced increase in respiration could be blocked by oligomycin, an inhibitor of mitochondrial ATP synthase, suggesting control by increased cytoplasmic ATP turnover. The stimulation of respiration was not associated with changes in the activity of mitochondrial electron transfer enzymes or permeability of the inner membrane. Several inhibitors of processes which used ATP were screened for their effects on the basal respiration rate and on the radiation response. In irradiated thymocytes, an enhancement of inhibition of respiration by ouabain, La 3+ and cycloheximide was observed. These results indicate that the radiation-induced stimulation of respiration is due to changes in ion homeostasis and protein synthesis. The effect of X irradiation was shown to be independent of the redox status of nonprotein thiols and was not associated with detectable changes in some products of lipid peroxidation. The radiation-induced decrease in activity of superoxide dismutase suggests free radical involvement in deleterious effects of radiation. 43 refs., 2 figs., 3 tabs

  14. Targeting mitochondrial respiration as a therapeutic strategy for cervical cancer.

    Science.gov (United States)

    Tian, Shenglan; Chen, Heng; Tan, Wei

    2018-05-23

    Targeting mitochondrial respiration has been documented as an effective therapeutic strategy in cancer. However, the impact of mitochondrial respiration inhibition on cervical cancer cells are not well elucidated. Using a panel of cervical cancer cell lines, we show that an existing drug atovaquone is active against the cervical cancer cells with high profiling of mitochondrial biogenesis. Atovaquone inhibited proliferation and induced apoptosis with varying efficacy among cervical cancer cell lines regardless of HPV infection, cellular origin and their sensitivity to paclitaxel. We further demonstrated that atovaquone acts on cervical cancer cells via inhibiting mitochondrial respiration. In particular, atovaquone specifically inhibited mitochondrial complex III but not I, II or IV activity, leading to respiration inhibition and energy crisis. Importantly, we found that the different sensitivity of cervical cancer cell lines to atovaquone were due to their differential level of mitochondrial biogenesis and dependency to mitochondrial respiration. In addition, we demonstrated that the in vitro observations were translatable to in vivo cervical cancer xenograft mouse model. Our findings suggest that the mitochondrial biogenesis varies among patients with cervical cancer. Our work also suggests that atovaquone is a useful addition to cervical cancer treatment, particularly to those with high dependency on mitochondrial respiration. Copyright © 2018 Elsevier Inc. All rights reserved.

  15. Two Proximal Skin Electrodes — A Respiration Rate Body Sensor

    Directory of Open Access Journals (Sweden)

    Viktor Avbelj

    2012-10-01

    Full Text Available We propose a new body sensor for extracting the respiration rate based on the amplitude changes in the body surface potential differences between two proximal body electrodes. The sensor could be designed as a plaster-like reusable unit that can be easily fixed onto the surface of the body. It could be equipped either with a sufficiently large memory for storing the measured data or with a low-power radio system that can transmit the measured data to a gateway for further processing. We explore the influence of the sensor’s position on the quality of the extracted results using multi-channel ECG measurements and considering all the pairs of two neighboring electrodes as potential respiration-rate sensors. The analysis of the clinical measurements, which also include reference thermistor-based respiration signals, shows that the proposed approach is a viable option for monitoring the respiration frequency and for a rough classification of breathing types. The obtained results were evaluated on a wireless prototype of a respiration body sensor. We indicate the best positions for the respiration body sensor and prove that a single sensor for body surface potential difference on proximal skin electrodes can be used for combined measurements of respiratory and cardiac activities.

  16. Improvement of ballistocardiogram processing by inclusion of respiration information

    International Nuclear Information System (INIS)

    Tavakolian, Kouhyar; Vaseghi, Ali; Kaminska, Bozena

    2008-01-01

    In this paper a novel methodology for processing of a ballistocardiogram (BCG) is proposed in which the respiration signal is utilized to improve the averaging of the BCG signal and ultimately the annotation and interpretation of the signal. Previous research works filtered out the respiration signal while the novelty of the current research is that, rather than removing the respiration effect from the signal, we utilize the respiration information to improve the averaging and thus analysis and interpretation of the BCG signal in diagnosis of cardiac malfunctions. This methodology is based on our investigation that BCG cycles corresponding to the inspiration and expiration phases of the respiration cycle are different in morphology. BCG cycles corresponding to the expiration phase of respiration have been proved to be more closely related to each other when compared to cycles corresponding to inspiration, and therefore expiration cycles are better candidates to be selected for the calculation of the averaged BCG signal. The new BCG average calculated based on this methodology is then considered as the representative and a template of the BCG signal for further processing. This template can be considered as the output of a clinical BCG instrument with higher reliability and accuracy compared to the previous processing methods

  17. Intra-annual variability of carbon and nitrogen stable isotopes in suspended organic matter in waters of the western continental shelf of India

    Directory of Open Access Journals (Sweden)

    M. V. Maya

    2011-11-01

    Full Text Available Intra-annual variations of δ13C and δ15N of water-column suspended particulate organic matter (SPOM have been investigated to understand the biogeochemical cycling of C and N in the Western Continental Shelf of India (WCSI. The key issues being addressed are: how the δ15N of SPOM is affected by seasonally varying processes of organic matter production and respiration and how it relates to the δ15N of sedimentary organic matter that appears to show a decreasing trend despite an apparent intensification of seasonal oxygen deficiency over the past few decades? A secondary objective was to evaluate the sources of organic carbon. Elemental carbon and nitrogen concentrations, C/N ratios in SPOM, along with ancillary chemical and biological variables including phytoplankton pigment abundance were also determined on a seasonal basis (from March 2007 to September 2008, with the partial exception of the southwest (SW monsoon period. The results reveal significant shifts in isotopic signatures, especially δ15N, of SPOM before and after the onset of SW monsoon. Very low δ15N values, reaching a minimum of −4.17 ‰, are found during the pre-monsoon period. Our results provide the first direct evidence for the addition of substantial amounts of isotopically light nitrogen by the diazotrophs, especially Trichodesmium, in the region. The δ15N of SPOM is generally lower than the mean value (7.38 ‰ for surficial sediments, presumably because of diagenetic enrichment. The results support the view that sedimentary δ15N may not necessarily reflect denitrification intensity in the overlying waters due to diverse sources of nitrogen and variability of its isotopic composition. The observed intra-annual variability of δ13C of SPOM during the pre-monsoon and post-monsoon periods is generally small. Phytoplankton production and probably species

  18. Particulate contamination spectrometer. Volume 1: Technical report

    Science.gov (United States)

    Schmitt, R. J.; Boyd, B. A.; Linford, R. M. F.

    1975-01-01

    A laser particulate spectrometer (LPS) system was developed to measure the size and speed distributions of particulate (dusts, aerosols, ice particles, etc.) contaminants. Detection of the particulates was achieved by means of light scattering and extinction effects using a single laser beam to cover a size range of 0.8 to 275 microns diameter and a speed range of 0.2 to 20 meter/second. The LPS system was designed to operate in the high vacuum environment of a space simulation chamber with cold shroud temperatures ranging from 77 to 300 K.

  19. Removal of particulates from nuclear offgas

    International Nuclear Information System (INIS)

    Burchsted, C.A.

    1976-01-01

    Particulate removal from nuclear offgases can be broken down into three parts: pretreatment, prefiltration, and absolute filtration. Pretreatment, using conventional air cleaning devices in most cases, is sometimes required to temper the gases and remove heavy concentrations of particulate matter. Prefiltration, if required, serves primarily to protect the final filter stages from heavy dust loadings in order to extend their life. HEPA filters are the most commonly used ''absolute'' filtration devices and are always required for removal of submicrometer particulates that cannot be removed effectively by other devices

  20. Electrically heated particulate filter enhanced ignition strategy

    Science.gov (United States)

    Gonze, Eugene V; Paratore, Jr., Michael J

    2012-10-23

    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. A grid of electrically resistive material is applied to an exterior upstream surface of the PF and selectively heats exhaust passing through the grid to initiate combustion of particulates within the PF. A catalyst coating applied to at least one of the PF and the grid. A control module estimates a temperature of the grid and controls the engine to produce a desired exhaust product to increase the temperature of the grid.