Sample records for suspended particulate material

  1. 40 CFR 227.32 - Liquid, suspended particulate, and solid phases of a material. (United States)


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

  2. Seasonal variation of polychlorinated biphenyl congeners in surficial sediment, trapped settling material, and suspended particulate material in Lake Michigan, USA. (United States)

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


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

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

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


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

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


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

  5. 23 Elemental Composition of Suspended Particulate Matter ...

    African Journals Online (AJOL)


    Elemental Composition of Suspended Particulate Matter Collected at Two Different. Heights above the Ground in A Sub-Urban Site in Kenya. Gitari W. M1, Kinyua A. M. 2, Kamau G. N3 and C. K. Gatebe C. K4. Abstract. Suspended particulate matter samples were collected in a sub-urban area in Nairobi over a 12 month ...

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

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


    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 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 rivers. Novel findings include environmental Kd calculations, the occurrence of contaminants in river headwaters, increases in contaminant metabolite concentrations

  7. 40 CFR 230.21 - Suspended particulates/turbidity. (United States)


    ... time. These new levels may reduce light penetration and lower the rate of photosynthesis and the... suspended particulates persist. The biological and the chemical content of the suspended material may react with the dissolved oxygen in the water, which can result in oxygen depletion. Toxic metals and organics...

  8. Environmental toxicology: Acute effects of suspended particulate ...

    African Journals Online (AJOL)

    ... 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. KEY WORDS: Environmental toxicology, Suspended particulate matter, Dust analysis, Hematological indices, Wister albino rats. Bull.

  9. Environmental toxicology: Acute effects of suspended particulate ...

    African Journals Online (AJOL)

    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 ...

  10. Distribution and geochemical composition of suspended particulate material in the shallow embayment of northern Thermaikos Gulf, Greece (United States)

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


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

  11. Novel concepts for preparation of reference materials as whole water samples for priority substances at nanogram-per-liter level using model suspended particulate matter and humic acids. (United States)

    Elordui-Zapatarietxe, Saioa; Fettig, Ina; Philipp, Rosemarie; Gantois, Fanny; Lalère, Béatrice; Swart, Claudia; Petrov, Panayot; Goenaga-Infante, Heidi; Vanermen, Guido; Boom, Gerard; Emteborg, Håkan


    One of the unresolved issues of the European Water Framework Directive is the unavailability of realistic water reference materials for the organic priority pollutants at low nanogram-per-liter concentrations. In the present study, three different types of ready-to-use water test materials were developed for polycyclic aromatic hydrocarbons (PAHs), polybrominated diphenyl ethers (PBDEs) and tributyltin (TBT) at nanogram-per-liter levels. The first type simulated the dissolved phase in the water and comprised of a solution of humic acids (HA) at 5 mg L(-1) dissolved organic carbon (DOC) and a spike of the target compounds. The second type of water sample incorporated the particulate phase in water. To this end, model suspended particulate matter (SPM) with a realistic particle size was produced by jet milling soil and sediments containing known amounts of PAHs, PBDEs and TBT and added as slurry to mineral water. The most complex test materials mimicked "whole water" consequently containing both phases, the model SPM and the HA solution with the target analytes strongly bound to the SPM. In this paper, the development of concepts, processing of the starting materials, characterisation of the HA and model SPMs as well as results for homogeneity and stability testing of the ready-to-use test materials are described in detail.

  12. The chemistry of suspended particulate material in a highly contaminated embayment of Port Jackson (Australia) under quiescent, high-wind and heavy-rainfall conditions (United States)

    Birch, Gavin; O'Hea, Laura


    This study investigated physico-chemical characteristics of the water column and chemistry of suspended particulate material (SPM) under quiescent, high-wind and high-wind/heavy-rainfall conditions in Homebush Bay, a highly contaminated embayment of Port Jackson (Australia) to distinguish source and possible adverse effects to benthic and pelagic animals. Mean concentrations in surficial sediment were chemistry indicated these metals had multiple sources, i.e. the estuary, stormwater and industry. Mean total suspended solids (TSS) were 7, 17 and 20 mg L-1 during quiescent, high-rainfall and heavy rainfall/high wind conditions, respectively, whereas SPM Cd, Co, Cr, Cu, Ni, Pb and Zn concentrations varied between 13-25, 166-259, 127-198, 38-82, 236-305 and 605-865 μg g-1, respectively under these conditions. TSS and total water metal concentrations were lowest during quiescent conditions. High TSS and metal loads in surface water characterised high-rainfall events. Wind-induced resuspension contributed the greatest mass of SPM and metals to the water column. Benthic animals may be adversely affected by Pb and Zn in sediment. Total water Cu and Zn concentrations may pose a risk to filter-feeding animals in the water column due to resuspension of contaminated sediment.

  13. Suspended particulate matter and vertical fluxes of sedimentary material in bays of the Murmansk (Barents Sea) and Karelian (White Sea) coasts (United States)

    Mityaev, M. V.; Gerasimova, M. V.; Berger, V. Ja.


    Synchronous measurement of the total suspended organic and mineral particulate matter, together with vertical sedimentary matter flux, carried out in various areas of Yarnyschnaya Inlet (Murmansk coast of the Barents Sea) and Chupa Inlet (Karelian coast of the White Sea) revealed that the seston organic component plays no part in sedimentation, being almost completely utilized in the water column, while the majority of mineral matter is transported out of the bay. The total amount of suspended matter and its components in the water column is estimated, as well as the total flux of sedimentary matter to the bottom of Chupa and Yarnyschnaya inlets.

  14. A critical and comparative appraisal of polycyclic aromatic hydrocarbons in sediments and suspended particulate material from a large South American subtropical estuary. (United States)

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


    The Paranaguá Estuarine Complex (PEC) is an important socioeconomic estuary of the Brazilian coast that is influenced by the input of pollutants like polycyclic aromatic hydrocarbons (PAHs). Because of the apparent lack of comparative studies involving PAHs in different estuarine compartments, the aim of this study was to determine and compare PAH concentrations in surface sediment and suspended particulate material (SPM) in the PEC to evaluate their behaviour, compositions, sources and spatial distributions. The total PAH concentrations in the sediment ranged from 0.6 to 63.8 ng g(-1) (dry weight), whereas in the SPM these concentrations ranged from 391 to 4164 ng g(-1). Diagnostic ratios suggest distinct sources of PAHs to sediments (i.e., pyrolytic sources) and SPM (i.e., petrogenic sources such as vessel traffic). Thus, the recent introduction of PAHs is more clearly indicated in the SPM since oil related-compounds (e.g., alkyl-PAHs) remain present in similar concentrations. Further, this matrix may better reflect the current state of the environment at the time of sampling because of the absence of significant degradation. Copyright © 2016 Elsevier Ltd. All rights reserved.

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

    African Journals Online (AJOL)

    Surface water concentrations of inorganic nutrients and suspended particulate matter (SPM) components from Mtwapa and Shirazi creeks in Kenya were measured and compared. This was aimed at assessing the contribution of phytoplankton carbon, particulate organic carbon (POC) and detritus on the total SPM pool, and ...

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

    African Journals Online (AJOL)

    The particulate samples from where the metals were characterized and quantified, were collected between December 2007 and March 2008, using a Gravimetric technique a portable SKC 506673 High volume Gravimetric sampler. The air particulate samples were collected from the kitchens, living rooms and outdoor ...

  17. [Light absorption by suspended particulate matter in Chagan Lake, Jilin]. (United States)

    Wang, Yuan-Dong; Liu, Dian-Wei; Song, Kai-Shan; Zhang, Bai; Wang, Zong-Ming; Jiang, Guang-Ji; Tang, Xu-Guang; Lei, Xiao-Chun; Wu, Yan-Qing


    Spectral characteristics and the magnitudes of light absorption by suspended particulate matter were determined by spectrophotometry in this optically complex Lake Chagan waters for the purpose of surveying the natural variability of the absorption coefficients to parameterize the bio-optical models for converting satellite or in-situ water reflectance signatures into water quality information. Experiments were carried out on seasonal frozen Lake Chagan, one representative inland case-2 water body in Northeast of China. Particulate absorption properties analyzed using the field data on July 15th and October 12th 2009 were measured using the quantitative filter technique to produce absorption spectra containing several fractions that could be attributed to two main optical active constituents (OACs) phytoplankton pigments and non-algal particulates (mineral sediments, and organic detritus). Results suggested that the suspended particulate matter (SPM) concentration was higher while phytoplankton biomass (chlorophyll-a concentration) was lower in July and that in October. The spectral shape of total suspended particulate matter resembled that of non-algal particulates which contributed greater than phytoplankton in total particulate absorption during both periods. An obvious absorption peak occurring at around 440 nm exhibited an increase in phytoplankton contribution in October. Non-algal particulate absorption at 440 nm (a(NAP) (440)) had better correlation with total suspended particulate matter concentration than that with chlorophyll-a over the two periods. Light absorption by phytoplankton pigments in the Chagan lake region was generally lower than that of non-algal components. Chl. a dominating phytoplankton pigment composition functioned exponentially with its absorption coefficients at 440 and 675 nm specifically, the average values of which in July were 0.146 8 m2 x mg(-1) and 0.050 3 respectively while in October they were 0.153 3 and 0.013 2 m2 x mg(-1

  18. 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 ...

  19. 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,very little is known about their cycling in marine waters.In this research,we assessed the distribution and cycling of these compounds in waters of the Bay of Bengal.For this purpose,samples of suspended particulate matter (SPM)were collected from 8 ...

  20. Assessment of CO, CO2 and Suspended Particulate Matter Emissions

    Directory of Open Access Journals (Sweden)

    Bala Isah ABDULKARIM


    Full Text Available The concentrations of carbon oxides (CO and CO2 and suspended particulate matter at Benue Cement Company (BCC and Tse-Kucha community was investigated. Results obtained, shows that concentrations of carbon dioxide of 34.40ppm, 39.50 ppm, 48.50 ppm, 78.55 ppm, 65.25 ppm, 26.80 ppm and 29.5 ppm for quarry, raw mill, cement mill, Kiln, packing house, limestone stockpile and Tse-Kucha community respectively were below the maximum standard natural concentration of CO2 in atmosphere of 600ppm while concentrations of CO (1.25ppm - 4.00ppm measured in all the sample stations were below the Nigerian Ambient Air Quality Standards (NAAQS and WHO max limit of 10 ppm - 20 ppm for an 8-hourly average time. Lastly, the concentrations of suspended particulate matter of 375 μg/m3, 338 μg/m3 and 290 μg/m3 at the cement mill, packing house and raw mill respectively were also above the World Health Organization’s (WHO’s Guidelines and Standards for Ambient Air Quality which stipulates a range of 150 μg/m3 to 230 μg/m3 for a 24- hourly average.

  1. Optical and Gravimetric Partitioning of Coastal Ocean Suspended Particulate Inorganic Matter (PIM) (United States)

    Stavn, R. H.; Zhang, X.; Falster, A. U.; Gray, D. J.; Rick, J. J.; Gould, R. W., Jr.


    Recent work on the composition of suspended particulates of estuarine and coastal waters increases our capabilities to investigate the biogeochemal processes occurring in these waters. The biogeochemical properties associated with the particulates involve primarily sorption/desorption of dissolved matter onto the particle surfaces, which vary with the types of particulates. Therefore, the breakdown into chemical components of suspended matter will greatly expand the biogeochemistry of the coastal ocean region. The gravimetric techniques for these studies are here expanded and refined. In addition, new optical inversions greatly expand our capabilities to study spatial extent of the components of suspended particulate matter. The partitioning of a gravimetric PIM determination into clay minerals and amorphous silica is aided by electron microprobe analysis. The amorphous silica is further partitioned into contributions by detrital material and by the tests of living diatoms based on an empirical formula relating the chlorophyll content of cultured living diatoms in log phase growth to their frustules determined after gravimetric analysis of the ashed diatom residue. The optical inversion of composition of suspended particulates is based on the entire volume scattering function (VSF) measured in the field with a Multispectral Volume Scattering Meter and a LISST 100 meter. The VSF is partitioned into an optimal combination of contributions by particle subpopulations, each of which is uniquely represented by a refractive index and a log-normal size distribution. These subpopulations are aggregated to represent the two components of PIM using the corresponding refractive indices and sizes which also yield a particle size distribution for the two components. The gravimetric results of partitioning PIM into clay minerals and amorphous silica confirm the optical inversions from the VSF.

  2. Transporting particulate material (United States)

    Aldred, Derek Leslie [North Hollywood, CA; Rader, Jeffrey A [North Hollywood, CA; Saunders, Timothy W [North Hollywood, CA


    A material transporting system comprises a material transporting apparatus (100) including a material transporting apparatus hopper structure (200, 202), which comprises at least one rotary transporting apparatus; a stationary hub structure (900) constraining and assisting the at least one rotary transporting apparatus; an outlet duct configuration (700) configured to permit material to exit therefrom and comprising at least one diverging portion (702, 702'); an outlet abutment configuration (800) configured to direct material to the outlet duct configuration; an outlet valve assembly from the material transporting system venting the material transporting system; and a moving wall configuration in the material transporting apparatus capable of assisting the material transporting apparatus in transporting material in the material transporting system. Material can be moved from the material transporting apparatus hopper structure to the outlet duct configuration through the at least one rotary transporting apparatus, the outlet abutment configuration, and the outlet valve assembly.

  3. A review of the effects of particle types on oil-suspended particulate matter aggregate formation (United States)

    Loh, Andrew; Yim, Un Hyuk


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

  4. 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...

  5. 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.

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

  6. Methods for Coating Particulate Material (United States)

    Littman, Howard (Inventor); Plawsky, Joel L. (Inventor); Paccione, John D. (Inventor)


    Methods and apparatus for coating particulate material are provided. The apparatus includes a vessel having a top and a bottom, a vertically extending conduit having an inlet in the vessel and an outlet outside of the vessel, a first fluid inlet in the bottom of the vessel for introducing a transfer fluid, a second fluid inlet in the bottom of the vessel for introducing a coating fluid, and a fluid outlet from the vessel. The method includes steps of agitating a material, contacting the material with a coating material, and drying the coating material to produce a coated material. The invention may be adapted to coat aerogel beads, among other materials. A coated aerogel bead and an aerogel-based insulation material are also disclosed.

  7. Material Instabilities in Particulate Systems (United States)

    Goddard, J. D.


    Following is a brief summary of a theoretical investigation of material (or constitutive) instability associated with shear induced particle migration in dense particulate suspensions or granular media. It is shown that one can obtain a fairly general linear-stability analysis, including the effects of shear-induced anisotropy in the base flow as well as Reynolds dilatancy. A criterion is presented here for simple shearing instability in the absence of inertia and dilatancy.

  8. 40 CFR 52.330 - Control strategy: Total suspended particulates. (United States)


    ... 40 Protection of Environment 3 2010-07-01 2010-07-01 false Control strategy: Total suspended... PROGRAMS (CONTINUED) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS Colorado § 52.330 Control strategy..., the State must repromulgate Regulation No. 1 to satisfy reasonably available control technology...

  9. 78 FR 22425 - Designation of Areas for Air Quality Planning Purposes; State of Nevada; Total Suspended Particulate (United States)


    ... AGENCY 40 CFR Part 81 Designation of Areas for Air Quality Planning Purposes; State of Nevada; Total... is taking direct final action to delete certain area designations for total suspended particulate... the attainment or unclassifiable areas for total suspended particulate in Clark County as well as the...

  10. 78 FR 22501 - Designation of Areas for Air Quality Planning Purposes; State of Nevada; Total Suspended Particulate (United States)


    ... AGENCY 40 CFR Part 81 Designation of Areas for Air Quality Planning Purposes; State of Nevada; Total... proposing to delete certain area designations for total suspended particulate within the State of Nevada... unclassifiable areas for total suspended particulate in Clark County as well as the following nonattainment areas...



    Ryosuke, KITAMURA; Seisaku, FUKUHARA; George, KISANUKI; Professor, Dept. of Ocean Civil Engineering, Kagoshima University; Technical Clerk, Kagoshima Prefecture (formerly Graduate Student, Kagoshima Univ.); Graduate Student, Kagoshima University


    A new slope stability analysis method based on consideration of particle scale is proposed for the analysis of the flowage of particulate material, in which the equilibrium condition of the particulate material is examined on the basis of the inter-particle force at a contact point caused by surface tension. The decrease in inter-particle force is considered as one of the main factors for the flowage of particulate material and corresponds to the slope failure. Several numerical experiments h...

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

    NARCIS (Netherlands)

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


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

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

    CSIR Research Space (South Africa)

    Terblanche, APS


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

  14. Levels of As, Pb, Cd and Fe in Suspended Particulate Matter (SPM ...

    African Journals Online (AJOL)

    Suspended Particulate Matter (SPM) collected from three different artisans' workshops was analyzed for As, Cd, Pb and Fe by Atomic Absorption Spectrophotometry (AAS). The range of SPM concentrations for the three workshops was 583-20,166Bg/m3. The highest concentrations of these elements were observed in Motor ...

  15. Role of livestock effluent suspended particulate in sealing effluent ponds. (United States)

    Bennett, J McL; Warren, B R


    Intensive livestock feed-lots have become more prevalent in recent years to help in meeting the predicted food production targets based on expected population growth. Effluent from these is stored in ponds, representing a potential concern for seepage and contamination of groundwater. Whilst previous literature suggests that effluent particulate can limit seepage adequately in combination with a clay liner, this research addresses potential concerns for sealing of ponds with low concentration fine and then evaluates this against proposed filter-cake based methodologies to describe and predict hydraulic reduction. Short soil cores were compacted to 98% of the maximum dry density and subject to ponded head percolation with unfiltered-sediment-reduced effluent, effluent filtered to sealing was shown to follow mathematical models of filter-cake formation, but without the formation of a physical seal on top of the soil surface. Management considerations based on the results are presented. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. 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


    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

  17. 2010 Lead (Pb) Air Monitoring Requirements & 2013 Method for Determination of Lead (Pb) in Total Suspended Particulate Matter Fact Sheets (United States)

    This page contains a variety of fact sheets and other documents that are supplementary to the 2010 final revisions to lead (Pb) ambient air monitoring requirements and the 2013 final method for determination of Pb in total suspended particulate matter.


    Blainey, A.


    A process is presented for forming coherent sheet material from particulate material such as granular or powdered metal, granular or powdered oxide, slurries, pastes, and plastic mixes which cohere under pressure. The primary object is to avoid the use of expensive and/ or short lived pressing tools, that is, dies and specially profiled rolls, and so to reduce the cost of the product and to prcvide in a simple manner for the making of the product in a variety of shapes or sizes. The sheet material is formed when the particulate material is laterally confined in a boundary material deformable in all lateral directions under axial pressure and then axially compressing the layer of particulate material together with the boundary material.

  19. Suspended particulate layers and internal waves over the southern Monterey Bay continental shelf: an important control on shelf mud belts? (United States)

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


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

  20. Laboratory investigation of oil–suspended particulate matter aggregation under different mixing conditions

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Juan, E-mail: [College of Chemistry Engineering, China University of Petroleum, Qingdao, Shandong Province 266580 (China); Khelifa, Ali [Emergencies Science and Technology Section, Environment Canada, Ottawa, ON, Canada K1A0H3 (Canada); Zhao, Chaocheng; Zhao, Dongfeng [College of Chemistry Engineering, China University of Petroleum, Qingdao, Shandong Province 266580 (China); Wang, Zhendi [Emergencies Science and Technology Section, Environment Canada, Ottawa, ON, Canada K1A0H3 (Canada)


    Oil–suspended particulate matter aggregation (OSA) has been recognized by the oil spill remediation community to effectively enhance the cleansing of spilled oil in the marine environment. While studies have investigated the application of mineral fines as an effective method to facilitate oil dispersion, decision-makers still lack information on the role of mixing energy in OSA formation and its significance to oil dispersion in real spills. This work studied the effect of level and duration of mixing energy on OSA formation using the standard reference material 1941b and Arabian light crude oil. The results showed that dispersed small oil droplets increased with an increase of both the level and duration of mixing energy to form multi-droplet OSAs. The sizes of the dispersed droplets varied between 5 and 10 μm under different conditions studied. The maximum oil trapping efficiency increased from 23% to 33%, the oil to sediment ratio increased from 0.30 to 0.43 g oil/g sediment, and the required shaking time decreased from 2.3 to 1.1 h as the shaking rate increased from 2.0 to 2.3 Hz. Based on the size measurement results, a breakage effect on the formed OSAs and sediment flocs was confirmed under high mixing energy level. - Highlights: • Dispersed oil droplets increased as the mixing energy increased. • Size of dispersed droplets increased from 5 to 10 μm as the mixing time increased. • Both level and duration of mixing energy increased the oil trapping efficiency. • The oil to sediment ratio increased from 0.2 to 0.5 as the mixing energy increased. • The higher the mixing energy, the stronger the breakage effect on formed aggregates exists.

  1. Distribution and sources of suspended particulate matter in the Kara Sea

    Directory of Open Access Journals (Sweden)

    M. Kravchishina


    Full Text Available The distribution of suspended particulate matter (SPM concentration in the Kara Sea was analysed based on ship and satellite data during the lowest ice cover periods in the Arctic (2007 and 2011. The distance of the river runoff with terrigenous SPM was recognized up to at least 76–76.5° N on the basis of isotope data and SPM concentrations and composition. The complex studies of SPM in the water column and in the benthic boundary layer provided new information about the supply and transformation of particles in the marine ecosystem.

  2. Mass transfer within electrostatic precipitators: in-flight adsorption of mercury by charged suspended particulates. (United States)

    Clack, Herek L


    Electrostatic precipitation is the dominant method of particulate control used for coal combustion, and varying degrees of mercury capture and transformation have been reported across ESPs. Nevertheless, the fate of gas-phase mercury within an ESP remains poorly understood. The present analysis focuses on the gas-particle mass transfer that occurs within a charged aerosol in an ESP. As a necessary step in gas-phase mercury adsorption or transformation, gas-particle mass transfer-particularly in configurations other than fixed beds-has received far less attention than studies of adsorption kinetics. Our previous analysis showed that only a small fraction of gas-phase mercury entering an ESP is likelyto be adsorbed by collected particulate matter on the plate electrodes. The present simplified analysis provides insight into gas-particle mass transfer within an ESP under two limiting conditions: laminar and turbulent fluid flows. The analysis reveals that during the process of particulate collection, gas-particle mass transfer can be quite high, easily exceeding the mass transfer to ESP plate electrodes in most cases. Decreasing particle size, increasing particle mass loading, and increasing temperature all result in increased gas-particle mass transfer. The analysis predicts significantly greater gas-particle mass transfer in the laminar limitthan in the turbulent limit; however, the differences become negligible under conditions where other factors, such as total mass of suspended particulates, are the controlling mass transfer parameters. Results are compared to selected pilot- and full-scale sorbent injection data.

  3. Method for dispersing catalyst onto particulate material (United States)

    Utz, Bruce R.; Cugini, Anthony V.


    A method for dispersing finely divided catalyst precursors onto the surface of coal or other particulate material includes the steps of forming a wet paste mixture of the particulate material and a liquid solution containing a dissolved transition metal salt, for instance a solution of ferric nitrate. The wet paste mixture is in a state of incipient wetness with all of this solution adsorbed onto the surfaces of the particulate material without the presence of free moisture. On adding a precipitating agent such as ammonia, a catalyst precursor such as hydrated iron oxide is deposited on the surfaces of the coal. The catalyst is activated by converting it to the sulfide form for the hydrogenation or direct liquefaction of the coal.

  4. Consumption-based Total Suspended Particulate Matter Emissions in Jing-Jin-Ji Area of China (United States)

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


    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

  5. Process for producing dispersed particulate composite materials (United States)

    Henager, Jr., Charles H.; Hirth, John P.


    This invention is directed to a process for forming noninterwoven dispersed particulate composite products. In one case a composite multi-layer film product comprises a substantially noninterwoven multi-layer film having a plurality of discrete layers. This noninterwoven film comprises at least one discrete layer of a first material and at least one discrete layer of a second material. In another case the first and second materials are blended together with each other. In either case, the first material comprises a metalloid and the second material a metal compound. At least one component of a first material in one discrete layer undergoes a solid state displacement reaction with at least one component of a second material thereby producing the requisite noninterwoven composite film product. Preferably, the first material comprises silicon, the second material comprises Mo.sub.2 C, the third material comprises SiC and the fourth material comprises MoSi.sub.2.

  6. Metal removal via particulate material in a lowland river system. (United States)

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


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

  7. Turbidity-based methods for continuous estimates of suspended sediment, particulate carbon, phosphorus and nitrogen fluxes (United States)

    Jomaa, Seifeddine; Alsuliman, Malek; Rode, Michael


    A good evaluation of surface water pollution is mainly limited by the monitoring strategy and sampling frequencies. Carbon and nutrient monitoring at finer time intervals is still very difficult and expensive. Therefore, establishing relationships between grab sampling and continuous commonly available data can be considered as a favorable solution to turn this problem. The aim of this study was to develop a method to continuously estimate instream sediment, carbon, nitrogen and phosphorus concentrations based on high resolution measurement of turbidity, discharge, electrical conductivity and oxygen concentration. To achieve our gaols, high frequency data (30 min interval) were generated during 3 years at the UFZ- TERENO platform Bode (Terrestrial Environmental Observatories). Samples were analysed for suspended sediment concentration (SSC), particulate organic carbon (POC), total organic carbon (TOC), particulate nitrogen (PN) and particulate phosphorus (PP) using simple and multiple linear regression models. For this study, measurements from six sub-catchments with different geographical characteristics were considered. The available data sets were divided into two years (2010-2012) calibration and one year (2012-2013) validation periods. Results revealed that the turbidity was the most predictor variable in all models, particularly for suspended sediment concentrations. For all gauging stations, the SSC could be explained using simple linear regression model by the turbidity with a lowest correlation coefficient of 0.93. The non-uniqueness of the simple linear equation obtained between the stations reflected the sensitivity of the turbidity signal to the differences in land use and agriculture management between the sub-catchments. Best predictions of POC, TOC, PP and PN were achieved when multiple linear regression models were used including discharge, electrical conductivity and oxygen concentrations as predictor variables in addition to turbidity (lowest

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

    Energy Technology Data Exchange (ETDEWEB)

    Hausstein, H.


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

  9. Methods and apparatus for coating particulate material (United States)

    Littman, Howard (Inventor); Plawsky, Joel L. (Inventor); Paccione, John D. (Inventor)


    Methods and apparatus for coating particulate material are provided. The apparatus includes a vessel having a top and a bottom, a vertically extending conduit having an inlet in the vessel and an outlet outside of the vessel, a first fluid inlet in the bottom of the vessel for introducing a transfer fluid, a second fluid inlet in the bottom of the vessel for introducing a coating fluid, and a fluid outlet from the vessel. The method includes steps of agitating a material, contacting the material with a coating material, and drying the coating material to produce a coated material. The invention may be adapted to coat aerogel beads, among other materials. A coated aerogel bead and an aerogel-based insulation material are also disclosed.

  10. Quantifying the response of optical backscatter devices and transmissometers to variations in suspended particulate matter (United States)

    Bunt, Jamie A. C.; Larcombe, Piers; Jago, Colin F.


    Optical instruments have been used effectively in studies of sediment dynamics for several decades. Without accurate instrument calibrations, calculated concentrations of suspended particulate matter (SPM) may be unreliable, with implications for interpretations of sedimentary processes and sediment fluxes. This review aims to quantify the effect of variations in SPM characteristics on the response of optical instruments (optical backscatter sensors OBS and transmissometers) and to note the implications for users of these instruments. A number of factors have a significant impact on instrument response, for example; a change in grain size from medium sands to fine silts may lead to a×100 increase in instrument response; flocculation of fine particles may decrease instrument response by×2; and the presence of plankton in suspension may lead to poor instrument calibrations of SPM concentration. Calibrations carried out in environments either with multi-modal bottom sediments, where flocculation of fine-grained sediments is likely, or where the hydrodynamics or grain type are highly variable must also include a determination of the changing nature of the suspended load in space and time. A more complete understanding of instrument response to SPM and of calibration requirements may enable optical devices to be used to a greater potential as long-term measures of SPM concentration, and also enable improvements in calculations of net sediment fluxes.

  11. Improving the description of the suspended particulate matter concentrations in the southern North Sea through assimilating remotely sensed data

    NARCIS (Netherlands)

    El Serafy, G.Y.; Eleveld, M.A.; Blaas, M.; van Kessel, T.; Gaytan Aguilar, S.; van der Woerd, H.J.


    The integration of remote sensing data of suspended particulate matter (SPM) into numerical models is useful to improve the understanding of the temporal and spatial behaviour of SPM in dynamic shelf seas. In this paper a generic method based on the Ensemble Kalman Filtering (EnKF) for assimilating

  12. Bacteriohopanepolyol distribution in Yenisei River and Kara Sea suspended particulate matter and sediments traces terrigenous organic matter input

    NARCIS (Netherlands)

    de Jonge, C.; Talbot, H.M.; Bischoff, J.; Cherkashov, G.; Sinninghe Damsté, J.S.


    Bacteriohopanepolyols (BHPs) are ubiquitous bacterial membrane lipids, encountered in soils, river and marine suspended particulate matter (SPM) and sediments. Their abundance and distribution provides a direct means to identify bacterial inputs and can be used to trace soil-derived bacterial

  13. 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.

    The present study estimate the suspended particulate matter in the Mandovi and Zuari estuaries. samples were collected from the Mandovi (M0A–M9) and Zuari (Z0–Z8) estuaries and Cumbarjua canal (C0–C3).The spatial distribution of SPM in the Ma...

  14. Methods and apparatus for handling or treating particulate material (United States)

    Littman, Howard (Inventor); Plawsky, Joel L. (Inventor); Paccione, John D. (Inventor)


    An improved draft tube spout fluid bed (DTSFB) mixing, handling, conveying, and treating apparatus and systems, and methods for operating are provided. The apparatus and systems can accept particulate material and pneumatically or hydraulically conveying the material to mix and/or treat the material. In addition to conveying apparatus, a collection and separation apparatus adapted to receive the conveyed particulate material is also provided. The collection apparatus may include an impaction plate against which the conveyed material is directed to improve mixing and/or treatment. The improved apparatus are characterized by means of controlling the operation of the pneumatic or hydraulic transfer to enhance the mixing and/or reacting by controlling the flow of fluids, for example, air, into and out of the apparatus. The disclosed apparatus may be used to mix particulate material, for example, mortar; react fluids with particulate material; coat particulate material, or simply convey particulate material.

  15. Seasonal trends of benzo(apyrene in suspended particulate matter in urban areas of Belgrade, Serbia

    Directory of Open Access Journals (Sweden)

    Snežana Matić-Besarabić


    Full Text Available Polycyclic aromatic hydrocarbons (PAHs were identified to be one of the major toxic air pollutants in urban environment. PAHs are mostly formed during incomplete combustion or pyrolysis of organic material. According to Serbian National Legislation, benzo(apyrene (BaP concentration in total suspended particles (TSP in ambient air in the Belgrade metropolitan area has been determined in the last ten years, as a part of a local air pollution monitoring program performed by the Public Health Institute of Belgrade and funded by Belgrade’s Municipality. Air samples for analysis of BaP in suspended particleshave been collected (as 24 h sample once per month at selected onitoring sites within the municipal air quality monitoring network. At the beginning, according to National Regulation, all samples were taken as total suspended particles (TSP. Since mid-2008, the procedure of sampling methodology was harmonized with EU requirements and solid fraction PM10 has been collected and analyzed using GC/MS. In this study, we have analyzed results of TSP collected between 2005 and 2008. Looking through the results obtained during the period of a whole year, it can be noticed that concentrations of BaP were much higher during winter season at almost all measuring sites.

  16. Biogenic vanadium in total suspended particulate matter from Cabo Frio upwelling region, Southeast, Brazil (United States)

    Sella, Silvia M.; Neves, Alessandra F.; Moreira, Josino Costa; Silva-Filho, Emmanoel V.

    In this work total suspended particulate (TSP) was collected during a year, in two municipalities located in a coastal region of Rio de Janeiro State, Southeast, Brazil, from February 2004 to January 2005. Two sites were chosen: site 1 located in front of the sea and representative of sea salt spray influence; site 2 in a tall booth of a highway representing vehicle exhaust influence. Samples were collected in glass fibre filters using Hi-Vol samplers and stored. 1/8 of those loaded filters were cut and digested in a microwave oven. The extract obtained was used to determine metal Ca, Cu, Mo, Mn, Ti, V, Zn and K concentration in the atmosphere. The results showed that TSP levels in site 1 (23.1-659 μg m -3) was higher than in site 2 (24.5-55.6 μg m -3) due to marine aerosol which is responsible for particle emissions with higher diameter. Vanadium was the only element studied whose concentration were higher in site 1 (0.840-20.9 ng m -3) compared to site 2 (0.655-7.07 ng m -3). The highest vanadium concentrations in site 1 were obtained during upwelling events, with NE winds predominance at high speed, which indicates the influence of this phenomena in V presence in the atmosphere. Principal components analysis was able to identify atmospheric particulate sources distributed in four factors. In site 1, those factors explain 86.5% of total data variance and indicate two sources: continental and marine. In site 2, those factors explain 89.2% of total data variance and indicate that vehicle exhaust is the main metals source in the atmosphere.

  17. Production, handling and characterization of particulate materials

    CERN Document Server

    Meesters, Gabriel


    This edited volume presents most techniques and methods that have been developed by material scientists, chemists, chemical engineers and physicists for the commercial production of particulate materials, ranging from the millimeter to the nanometer scale.  The scope includes the physical and chemical background, experimental optimization of equipment and procedures, as well as an outlook on future methods. The books addresses  issues of industrial importance such as specifications, control parameter(s), control strategy, process models, energy consumption and discusses the various techniques in relation to potential applications. In addition to the production processes, all major unit operations and characterization methods are described in this book. It differs from other books which are devoted to a single technique or a single material. Contributors to this book are acknowledged experts in their field. The aim of the book is to facilitate comparison of the different unit operations leading to optimum...

  18. Horizontal distributions of biogenic and lithogenic elements of suspended particulate matter in the Mediterranean Sea (United States)

    Price, N. B.; Brand, T.; Pates, J. M.; Mowbray, S.; Theocharis, A.; Civitarese, G.; Miserocchi, S.; Heussner, S.; Lindsay, F.


    A study has been made of the distribution of terrigenous (Al and Mn ex, Fe ex) and biogenic (POC, PN tot, P org, Si bio, Ba ex) elements of suspended particulate matter (SPM) on a series of transects in three marginal areas of the Mediterranean Sea; the NW Mediterranean, the western Adriatic to the Strait of Otranto and the southern (Cretan) and northern Aegean Sea, with the intention of assessing the influence that river discharges have on their concentrations. In the Adriatic, high Al concentrations (60-200 μgl -1) occur as a consequence of direct discharge from the River Po but importantly from sediment resuspension the amount of which, under steady state conditions, is also related to riverine discharge. In the Otranto Strait high Al concentrations overlie its western shelf and slope. On the NW Mediterranean only waters influenced by the River Rhone, as off Banyuls-sur-mer, show high Al. Particulate Mn is mostly river derived, but principally exists in marginal areas from redox cycling in surficial sediments, a consequence of high biological production induced by nutrient discharges from rivers. High particulate Mn ex concentrations were measured in the northern Adriatic, off Banyuls-sur-mer and the northern Aegean, where there are strong river influences. In contrast, the more oligotrophic seawaters off Marseilles, the Balearics and the Cretan Sea show lower concentrations of Mn ex, and depth profiles of Mn ex especially in the latter area are similar to those found in ocean waters. Of the biogenic elements studied, the assumed presence of terrigenous organic carbon, especially on the Adriatic shelf, largely precludes POC concentrations from being an indicator of marine production. A better guide to productivity induced by river nutrient discharges is seen in the distribution of P org and Si bio concentrations, which show a gradual southward reduction along the Adriatic shelf and higher concentrations off Banyuls-sur-mer than on other transects in the NW

  19. Simultaneous atmospheric correction and quantification of suspended particulate matter in the Guadalquivir estuary from Landsat images (United States)

    Carpintero, M.; Polo, M. J.; Suhyp Salama, Mhd.


    Earth observations (EOs) following empirical and/or analytical approaches are a feasible alternative to obtain spatial and temporal distribution of water quality variables. The limitations observed in the use of empirical approaches to estimate high concentrations of suspended particulate matter (SPM) in the estuarine water of Guadalquivir have led the authors to use a semi-analytical model, which relates the water constituents' concentration to the water leaving reflectance. In this work, the atmospheric correction has been carried out simultaneously and the aerosol reflectance and backscattering coefficients of SPM obtained. The results are validated using in situ SPM data series provided by a monitoring network in the study area. The results show that the model allows us to successfully estimate backscattering coefficients of SPM in the estuary, differentiating clear and turbid water and using two ɛ(4,5) .These considerations improve the value of R2 from 0.68 (single ɛ(4,5)) to 0.86 (two ɛ( 4,5)) on 18 May 2009. This method could be used as a preliminary approach to obtain SPM concentration in the Guadalquivir estuary with the limitations that the model shows for turbid waters.

  20. Simultaneous atmospheric correction and quantification of suspended particulate matter in the Guadalquivir estuary from Landsat images

    Directory of Open Access Journals (Sweden)

    M. Carpintero


    Full Text Available Earth observations (EOs following empirical and/or analytical approaches are a feasible alternative to obtain spatial and temporal distribution of water quality variables. The limitations observed in the use of empirical approaches to estimate high concentrations of suspended particulate matter (SPM in the estuarine water of Guadalquivir have led the authors to use a semi-analytical model, which relates the water constituents’ concentration to the water leaving reflectance. In this work, the atmospheric correction has been carried out simultaneously and the aerosol reflectance and backscattering coefficients of SPM obtained. The results are validated using in situ SPM data series provided by a monitoring network in the study area. The results show that the model allows us to successfully estimate backscattering coefficients of SPM in the estuary, differentiating clear and turbid water and using two ε(4,5 .These considerations improve the value of R2 from 0.68 (single ε(4,5 to 0.86 (two ε( 4,5 on 18 May 2009. This method could be used as a preliminary approach to obtain SPM concentration in the Guadalquivir estuary with the limitations that the model shows for turbid waters.

  1. Determination of suspended particulate matter concentration from turbidity measurements: particle size effects and calibration procedures (United States)

    Pfannkuche, J.; Schmidt, A.


    Measurements of suspended particulate matter concentration and turbidity point towards the possibility of a site-specific algorithm (SPM), relating SPM to nephelometric turbidity units (NTU). In this paper regression models are presented that account for changes in the relationship of SPM and NTU as a result of changes in particle properties. The models have been developed by the use of daily measurements of SPM concentration and a continuous record of turbidity for the period from June 1996 to February 2001 in the River Elbe, a major river in the eastern part of Germany.The effect of changes in the particle properties with increasing water discharge was taken into account by varying the slope of a linear regression equation according to a logistic function. Water discharge, Q, was defined to be the only variable of this function - as an adequate substitute of the parameter bottom shear stress, which cannot be measured directly. Measurements of flow velocity in the River Elbe show that bottom shear stress is related almost linearly to water discharge up to bankful discharges.Regression models with slopes varying continuously with hydraulic parameters may account for the effects resulting from changes of particle characteristics and thus may have some advantages compared with models with a constant slope or models calibrated for different seasons.

  2. Suspended particulate matter collection methods influence the quantification of polycyclic aromatic compounds in the river system. (United States)

    Abuhelou, Fayez; Mansuy-Huault, Laurence; Lorgeoux, Catherine; Catteloin, Delphine; Collin, Valéry; Bauer, Allan; Kanbar, Hussein Jaafar; Gley, Renaud; Manceau, Luc; Thomas, Fabien; Montargès-Pelletier, Emmanuelle


    In this study, we compared the influence of two different collection methods, filtration (FT) and continuous flow field centrifugation (CFC), on the concentration and the distribution of polycyclic aromatic compounds (PACs) in suspended particulate matter (SPM) occurring in river waters. SPM samples were collected simultaneously with FT and CFC from a river during six sampling campaigns over 2 years, covering different hydrological contexts. SPM samples were analyzed to determine the concentration of PACs including 16 polycyclic aromatic hydrocarbons (PAHs), 11 oxygenated PACs (O-PACs), and 5 nitrogen PACs (N-PACs). Results showed significant differences between the two separation methods. In half of the sampling campaigns, PAC concentrations differed from a factor 2 to 30 comparing FT and CFC-collected SPMs. The PAC distributions were also affected by the separation method. FT-collected SPM were enriched in 2-3 ring PACs whereas CFC-collected SPM had PAC distributions dominated by medium to high molecular weight compounds typical of combustion processes. This could be explained by distinct cut-off threshold of the two separation methods and strongly suggested the retention of colloidal and/or fine matter on glass-fiber filters particularly enriched in low molecular PACs. These differences between FT and CFC were not systematic but rather enhanced by high water flow rates.

  3. 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.


    .8 and 10.2 mg dry weight (DW) L− 1 and between 130.6 and 268.2 μg DW L− 1, respectively, in our study. Urbanization was the only land-use category correlating with both FA composition and concentrations, despite its low contribution to whole catchment (1.5–5.6%) and riparian buffer land cover (1......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....... Here, we analyzed land-use effects on the fatty acid (FA) composition and concentrations in suspended particulate organic matter (SPOM) along a fourth-order tropical river, the Rio das Mortes. Thereby, we aimed at testing the potential of fatty acids in riverine suspended particulate organic matter...

  4. 40 CFR Appendix G to Part 50 - Reference Method for the Determination of Lead in Suspended Particulate Matter Collected From... (United States)


    ... the sample as follows: Rinse watch glass and sides of beaker with D.I. water. 1.1 Ambient air suspended particulate matter is collected on a glass-fiber filter for 24 hours using... lead content of the sample is analyzed by atomic absorption spectrometry using an air-acetylene flame...

  5. How much suspended particulate matter enters long-term in-channel storage? (United States)

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


    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

  6. 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.

    Concentrations of Al, Fe, Mn and rare earth elements (REE) were measured in 122 samples of suspended particulate matter (SPM) and 70 surficial sediments from the Zuari estuary and the adjacent shelf to understand their distribution, provenance...

  7. Assessment of Internal Fabric of Particulate Materials (United States)

    Alshibi, Khalid A.


    Particle arrangement and distribution within a soil matrix has long been recognized as having significant influence on the mechanical behavior of cohesionless soils. It is well known that two soil specimens having the same grain type (e.g., quartz, feldspar, etc.), same grain size distribution and relative density (or void ratio) can display completely different mechanical behavior. Because of the different fabric configurations in the otherwise similar specimens, they are likely to have different mechanical properties such as stress-strain response, anisotropy, dilatancy, etc. Soil Fabric is defined as the arrangement of particles, particle groups and associated pore space. In the literature, fabric analysis techniques are mainly classified as destructive (e.g., specimen stabilization, thin-sectioning, and microscopy), and nondestructive techniques (e.g., magnetic resonance imaging, ultrasonic testing, x-ray radiography, and computed tomography). Quantifying the void ratio and its distribution is the main parameter used to describe the fabric of particulate materials. This paper presents a comprehensive literature review of fabric analysis techniques applied to particulate materials. In addition, the results of a comprehensive investigation to quantify void ratio of sand specimens will be presented and discussed. The sand used in the experiments in a natural, uniform rounded to sub-rounded silica sand known as F-75 banding sand with mean particle size of 0.22 mm. Uniform specimens and specimens subjected to different axial-strain levels tested under triaxial and biaxial conditions are examined to evaluate void ratio evolution and its distribution using destructive thin-sectioning and nondestructive Computed Tomography (CT) techniques. Details of a new innovative polygon generation technique called Voronoi tessellation used to quantify void ratio of microscopic images of sand grains will be presented and compared to classical Oda's method. Finally, frequency

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

    Directory of Open Access Journals (Sweden)

    M. El-Nouby Adam


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

  9. Rapidly changing distribution of velocity and suspended materials under the drifting Arctic sea ice (United States)

    Ha, Ho Kyung; Im, Jungho; Kim, Yong Hoon; Yae Son, Eun; Lee, Sanggyun


    In two summer seasons of 2011 and 2014, the short-term (1-4 days) ice-camp study has been conducted on the drifting Arctic sea ice. In particular, in 2014, the international collaboration with the Marginal Ice Zone program (sponsored by Office of Naval Research) has been integrated. The mooring package comprises the acoustic Doppler velocity profiler, holographic imaging camera, and conductivity-temperature-depth profiler, which are used to understand the dynamic behavior of sea ice and spatial-temporal variation of mixing layer (ML) and suspended particulate matters under the sea ice. Mooring data clearly shows the mixing and entrainment pattern in the upper ML in the marginal ice zone. When ice floes drift toward the pack ice, the upward entrainment from the seasonal pycnocline to sea ice-water boundary was induced by shear across ML and seasonal pycnocline. The entrainment speed was in the range of 0.25-2 m/hr, which matches well with thickening and thinning rate of ML during the near-inertial period (~12 hr). When ice floes drift toward the open ocean, the turbulent wakes at the advancing edge of ice were combined with the entrainment caused by near-inertial motion, which results in a complex mixing pattern of both upward and downward fluxes in the ML. Also, the acoustic backscatter observed by the acoustic Doppler current profiler and beam attenuation from transmissometer revealed the increased concentration of suspended particulate materials in the ML, which can be direct evidence visualizing the mixing pattern. Results suggest that the mixing and entrainment found in our study sustain particulate matters in suspension within the upper ML for a few months.

  10. 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...

  11. Experiments to investigate particulate materials in reduced gravity fields (United States)

    Bowden, M.; Eden, H. F.; Felsenthal, P.; Glaser, P. E.; Wechsler, A. E.


    Study investigates agglomeration and macroscopic behavior in reduced gravity fields of particles of known properties by measuring and correlating thermal and acoustical properties of particulate materials. Experiment evaluations provide a basis for a particle behavior theory and measure bulk properties of particulate materials in reduced gravity.

  12. Assessment of suspended particulate matters and their heavy metal content in the ambient air of Mobarakeh city, Isfahan, Iran


    Avazali Saririan Mobarakeh; Bibi Fatemeh Nabavi; Mahnaz Nikaeen; Mohammad Mehdi Amin; Akbar Hassanzadeh; Kazem Nadafi


    Aim: This study was carried out to investigate the quality of Mobarakeh ambient air in terms of suspended particles and heavy metals. Material and Methods: The current study was carried out in Mobarakeh city, Isfahan, Iran. Air sampling was performed in three sites for a 1-year period (in 2007). Measurement of total suspended particles (TSP) and heavy metals was achieved using high volume air sampler with fiberglass filter. The concentration of heavy metals, including Pb, Ni, Zn, Fe, and ...

  13. Influence of Hydrodynamic Sorting on the Composition and Age of Yellow River Suspended Particulate Organic Matter (United States)

    Yu, M.; Eglinton, T. I.; Haghipour, N.; Montluçon, D. B.; Wacker, L.; Hou, P.; Zhao, M.


    The transport of organic carbon (OC) by rivers to coastal oceans is an important component of the global carbon cycle. The Yellow River (YR), the second largest river in China, transports large amounts of particulate organic carbon (POC) to the Chinese marginal seas, with fossil and pre-aged (ca, 1600 yr) OC comprising the dominant components. However, the influence of hydrodynamic processes on the origin, composition and age of POC exported by the YR remains poorly understood, yet these processes likely ultimately play an important role in determining OC fate in the Chinese marginal seas. We address this question through bulk, biomarker and carbon isotopic (δ13C and Δ14C) characterization of organic matter associated with different grain size fractions of total suspended particles (TSP) in the YR. Surface TSP samples were collected in the spring, summer, fall and during the Water-Sediment Regulation period (WSR, July) of 2015. TSP samples were separated into five grain-size fractions (63μm) for organic geochemical and isotope analysis. Generally, the 16-32 and 32-63μm fractions contributed most of the TSP mass and the majority of OC resided in 16-32μm fraction. TOC% decreased with increasing grain size and 14C ages exhibited significant variability, ranging from 3,335 yr (63μm fraction in autumn), but did not show any systematic trend among grain size fractions or across sampling times. In contrast, compound-specific 14C analysis of long-chain n-fatty acids (C26-30 FAs) revealed two clear patterns: first, C26-30 FAs age decreased with increasing grain size for all sampling times; second, the C26-30 FAs age difference was the largest among the different size fractions during the WSR period, and smallest after the WSR. These findings have important implications for our understanding of riverine POC transport mechanisms and their influence on the dispersal and burial efficiency of terrestrial OC in coastal oceans.

  14. Suspended particulate composition: evolution along a river linear and influence of regime flow (United States)

    Le Meur, Mathieu; Montargès-Pelletier, Emmanuelle; Bauer, Allan; Gley, Renaud; Migot, Sylvie; Mansuy-Huault, Laurence; Lorgeoux, Catherine; Razafitianamaharavo, Angelina; Villièras, Frédéric


    Suspended Particulate Matters are recognized to play a crucial role in the transport and fate of chemicals like trace metal elements. The affinity of trace metals with natural SPM is influenced by (i) the nature of metal (ii) physical-chemical conditions of the water column (iii) SPM physical characteristics (grain size, surface area) (iiii) SPM chemical characteristics (elemental composition, mineralogy, organic composition). Some authors observed that the SPM composition was the predominant factor controlling the affinity of trace metals with natural SPM. One purpose of this work is to follow the physical and chemical characteristics of SPM along the river linear in order to better understand the affinity between SPM and heavy metals. One other purpose is to study the influence of regime flow on SPM physical and chemical composition in order to detect any variation of SPM composition with regime flow. SPM were sampled along Moselle river (North East of France) following an urbanization gradient. Two tributaries were also sampled, the Madon river which drains an agricultural catchment and the Fensch stream which flows through an ancient steel-making basin. SPM were sampled several times during high flow and low flow. Particulate matter was extracted on field using continuous flow field centrifuge. Frozen-dried samples were then characterized in terms of size distribution, elemental composition (ICP - AES, ICP - MS), mineralogy (XRD, FTIR, SEM, TEM), surface properties (gas adsorption techniques) and organic composition (Py-GC-MS and GC-MS). Grain size distribution evidenced the presence of coarser particles during high flow but no difference in the grain size distribution could be evidenced between the different stations. The grain size distribution of collected SPM appeared globally identical, although the increase of conductivity due to the junction of Meurthe river . In terms of composition, major element contents in SPM are characterized by the predominance of

  15. Particulate flux calculation based on metal contents and suspended sediment concentrations relationship: case study of turbid alpine river (Isere, France) (United States)

    Dutordoir, Solene; Nemery, Julien; Guedron, Stéphane; Arnaud, Jérémy; Minaudo, Camille; Belleudy, Philippe; Landas-Maneval, Jacqueline; Rivière, Carlos


    In the context of increasing stress on aquatic environment, the improvement of pollutant flux quantification in large rivers presents a strong stake. Isere at Grenoble city (5570 km2) is an alpine river in the Northern French Alps with high suspended sediment transport reaching 10 to 20 g L-1 during floods. It is known that for elements like P, Ni, Mn, Cr, Pb, Fe et Al, most of river transport is done under particulate forms. Isere River is susceptible to transport particulate pollutants such as metals, given mining history and industrial activities at the upstream watershed. Moreover, this river receives Grenoble city's effluents (500 000 inhabitants) and stormwaters during rain events. Three metals (Hg, Ni, Pb) identified as priority substances regarding European Water Framework Directive and As known to be one of the most metal of concern were chosen in this study. High frequency samplings of suspended sediments were realized between 2011 and 2012 in order to evaluate the temporal variation of metals contents and to determine geochemical background during high flow periods. In the same sampling site (situated upstream urban effluents of Grenoble city), discharge and suspended sediment concentration by turbidity were measured at 30 min frequency by a monitoring station. The use of historical and new databases ranging between low and high discharge (10 years return flood) allowed determining relationships between metal contents and suspended sediment concentrations and discharges. Results show a good correlation for the studied metals and permit to defined the geochemical backgrounds for each metals measured above 0.5 g L-1, (Hg = 68 +/- 48 ng g-1, Ni = 30 +/- 10 mg g-1, Pb = 43 +/-13 mg g-1, As = 15 +/- 4 mg g-1). These models were validated on a separated period than the one used for the calibration and applied to calculate particulate metals concentrations and associated incertitude at 30 min frequency using SSC and discharge database. Cumulative 30 minutes

  16. Design and evaluation of a low-volume total suspended particulate sampler (United States)

    The regulation of particulate matter (PM) emitted by agricultural sources, e.g., cotton gins, feed mills, and concentrated animal feeding operations (CAFOs), is based on downwind concentrations of particulate matter less than 10 and 2.5 'm (PM10 and PM2.5) aerodynamic equivalent diameter (AED). Both...

  17. Method for immobilizing particulate materials in a packed bed (United States)

    Even, Jr., William R.; Guthrie, Stephen E.; Raber, Thomas N.; Wally, Karl; Whinnery, LeRoy L.; Zifer, Thomas


    The present invention pertains generally to immobilizing particulate matter contained in a "packed" bed reactor so as to prevent powder migration, compaction, coalescence, or the like. More specifically, this invention relates to a technique for immobilizing particulate materials using a microporous foam-like polymer such that a) the particulate retains its essential chemical nature, b) the local movement of the particulate particles is not unduly restricted, c) bulk powder migration and is prevented, d) physical and chemical access to the particulate is unchanged over time, and e) very high particulate densities are achieved. The immobilized bed of the present invention comprises a vessel for holding particulate matter, inlet and an outlet ports or fittings, a loosely packed bed of particulate material contained within the vessel, and a three dimensional porous matrix for surrounding and confining the particles thereby fixing the movement of individual particle to a limited local position. The established matrix is composed of a series of cells or chambers comprising walls surrounding void space, each wall forming the wall of an adjacent cell; each wall containing many holes penetrating through the wall yielding an overall porous structure and allowing useful levels of gas transport.

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

    Fettweis, Michael; Baeye, Matthias; Francken, Frederic; Lauwaert, Brigitte; Van den Eynde, Dries; Van Lancker, Vera; Martens, Chantal; Michielsen, Tinne


    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-sampling, was applied to evaluate the effect. The data revealed that the SPM concentration near the bed was on average more than two times higher during the dredging experiment. The disposed material was mainly transported in the benthic layer and resulted in a long-term increase of SPM concentration and formation of fluid mud layers. The study shows that SPM concentration can be used as an indicator of environmental changes if representative time series are available. Copyright © 2010 Elsevier Ltd. All rights reserved.

  19. Particulate matter from re-suspended mineral dust and emergency cause-specific respiratory hospitalizations in Hong Kong (United States)

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


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

  20. Regulation of suspended particulate matter (SPM) in Indian coal-based thermal power plants (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.

  1. 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. (United States)

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


    The application of zinc (Zn) isotopes in bivalve tissues to identify zinc sources in estuaries was critically assessed. We determined the zinc isotope composition of mollusks (Crassostrea brasiliana and Perna perna) and suspended particulate matter (SPM) in a tropical estuary (Sepetiba Bay, Brazil) historically impacted by metallurgical activities. The zinc isotope systematics of the SPM was in line with mixing of zinc derived from fluvial material and from metallurgical activities. In contrast, source mixing alone cannot account for the isotope ratios observed in the bivalves, which are significantly lighter in the contaminated metallurgical zone (δ 66 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.

  2. Bacteriohopanepolyol distribution in Yenisei River and Kara Sea suspended particulate matter and sediments traces terrigenous organic matter input and submerged permafrost

    NARCIS (Netherlands)

    De Jonge, C.; Talbot, Helen M.; Bischoff, Juliane; Stadnitskaia, A.N.; Cherkashov, Georgy; Sinninghe Damsté, J.S.


    Bacteriohopanepolyols (BHPs) are ubiquitous bacterial membrane lipids, encountered in soils, river and marine suspended particulate matter (SPM) and sediments. Their abundance and distribution provides a direct means to identify bacterial inputs and can be used to trace soil-derived bacterial

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

    NARCIS (Netherlands)

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


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

  4. Semivolatile particulate organic material in southern Africa during SAFARI 2000 (United States)

    Eatough, D. J.; Eatough, N. L.; Pang, Y.; Sizemore, S.; Kirchstetter, T. W.; Novakov, T.; Hobbs, P. V.


    During August and September 2000, the University of Washington's (UW) Cloud and Aerosol Research Group (CARG) with its Convair-580 research aircraft participated in the Southern African Fire-Atmosphere Research Initiative (SAFARI) 2000 field study in southern Africa. Aboard this aircraft was a Particle Concentrator-Brigham Young University Organic Sampling System (PC-BOSS), which was used to determine semivolatile particulate material with a diffusion denuder sampler. Denuded quartz filters and sorbent beds in series were used to measure nonvolatile and semivolatile materials, respectively. Results obtained with the PC-BOSS are compared to those obtained with conventional quartz-quartz and Teflon-quartz filter pack samplers. Various 10-120 min integrated samples were collected during flights through the free troposphere, in the atmospheric boundary layer, and in plumes from savanna fires. Significant fine particulate semivolatile organic compounds (SVOC) were found in all samples. The SVOC was not collected by conventional filter pack samplers and therefore would not have been determined in previous studies that used only filter pack samplers. The SVOC averaged 24% of the fine particulate mass in emissions from the fires and 36% of the fine particulate mass in boundary layer samples heavily impacted by aged emissions from savanna fires. Concentrations of fine particulate material in the atmospheric mixed layer heavily impacted by aged savanna fire emissions averaged 130 μg m-3. This aerosol was 85% carbonaceous material.

  5. Method for dispersing catalyst onto particulate material and product thereof (United States)

    Utz, Bruce R.; Cugini, Anthony V.


    A method for dispersing finely divided catalyst precursors onto the surface of coal or other particulate material includes the steps of forming a wet paste mixture of the particulate material and a liquid solution containing a dissolved transition metal salt, for instance a solution of ferric nitrate. The wet paste mixture is in a state of incipient wetness with all of this solution adsorbed onto the surfaces of the particulate material without the presence of free moisture. On adding a precipitating agent such as ammonia, a catalyst precursor such as hydrated iron oxide is deposited on the surfaces of the coal. The catalyst is activated by converting it to the sulfide form for the hydrogenation or direct liquefaction of the coal.

  6. Characterisation of the suspended particulate matter in a stratified estuarine environment employing complementary techniques (United States)

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


    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.

  7. Semivolatile Particulate Organic Material Southern Africa during SAFARI 2000 (United States)

    Eatough, D. J.; Eatough, N. L.; Pang, Y.; Sizemore, S.; Kirchstetter, T. W.; Novakov, T.


    During August and September 2000, the University of Washington's Cloud and Aerosol Research Group (CARG) with its Convair-580 research aircraft participated in the Southern African Fire-Atmosphere Research Initiative (SAFARI) 2000 field study in southern Africa. Aboard this aircraft was a Particle Concentrator-Brigham Young University Organic Sampling System (PC-BOSS), which was used to determine semivolatile particulate material with a diffusion denuder sampler. Denuded quartz filters and sorbent beds in series were used to measure nonvolatile and semivolatile materials, respectively. Results obtained with the PC-BOSS are compared to those obtained with conventional quartz-quartz and Teflon-quartz filter pack samplers. Various 10-120 min integrated samples were collected during flights through the h e troposphere, in the atmospheric boundary layer, and in plumes from savanna fires. Significant fine particulate semivolatile organic compounds (SVOC) were found in all samples. The SVOC was not collected by conventional filter pack samplers and therefore would not have been determined in previous studies that used only filter pack samplers. The SVOC averaged 24% of the fine particulate mass in emissions from the fires and 36% of the fine particulate mass in boundary layer samples heavily impacted by aged emissions from savanna fires. Concentrations of fine particulate material in the atmospheric mixed layer heavily impacted by aged savanna frre emissions averaged 130 micrograms per cubic meter. This aerosol was 85% carbonaceous mated.

  8. Fluidizable particulate materials and methods of making same (United States)

    Gupta, Raghubir P.


    The invention provides fluidizable, substantially spherical particulate material of improved attrition resistance having an average particle size from about 100 to about 400 microns useful as sorbents, catalysts, catalytic supports, specialty ceramics or the like. The particles are prepared by spray drying a slurry comprising inorganic starting materials and an organic binder. Exemplary inorganic starting materials include mixtures of zinc oxide with titanium dioxide, or with iron oxide, alumina or the like. Exemplary organic binders include polyvinyl alcohol, hydroxypropylemethyl cellulose, polyvinyl acetate and the like. The spray dried particles are heat treated at a first temperature wherein organic binder material is removed to thereby provide a porous structure to the particles, and thereafter the particles are calcined at a higher temperature to cause reaction of the inorganic starting materials and to thereby form the final inorganic particulate material.

  9. Suspended particulate variations and mass size distributions of incense burning at Tzu Yun Yen temple in Taiwan, Taichung. (United States)

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


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

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

    Gould, Jessica; Kienast, Markus; Dowd, Michael


    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.

  11. Effect of the resuspension technique on distribution of the heavy metals in sediment and suspended particulate matter. (United States)

    Pourabadehei, Mehdi; Mulligan, Catherine N


    Harbour areas play important roles in the economy worldwide. Human activities, however, in those areas, generate contamination, which mostly accumulates in sediments. On the other hand, harbour areas have been facing deposition of significant amounts of sediment each year. As a consequence, shallowness and accumulation of contaminants in sediment become challenging issues in harbours. Among the various management options for remediation of contaminated sediments in harbours, resuspension technique was introduced as a new approach to address those issues. The concept of the resuspension method is that finer sediments have a greater tendency to adsorb the contamination. Therefore, removing the finer sediments instead of dredging the whole contaminated area is the main goal of the resuspension technique. The objective of this paper was to evaluate the effect of the resuspension method on reducing the concentration of contamination and distribution of heavy metals in sediment and suspended particulate matter. The resuspension method was successful in reducing the concentration of seven selected heavy metals (Cr, Ni, Cu, Zn, As, Cd and Pb) by removing just 4% of the contaminated sediment. The contamination intensity in the sediment, presented by geoaccumulation index, was reduced for Cd and Pb as the main contaminants by 26 and 28 percent and the rest of the selected heavy metals returned to the natural level. The results of the sequential extraction tests and enrichment factor implied that the resuspension technique is capable of decreasing the risk of remobilization of heavy metals in the aquatic ecosystem. Copyright © 2016 Elsevier Ltd. All rights reserved.

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

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


    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.

  13. A MODIS-Based Retrieval Model of Suspended Particulate Matter Concentration for the Two Largest Freshwater Lakes in China

    Directory of Open Access Journals (Sweden)

    Fangyuan Chen


    Full Text Available Suspended particulate matter concentration (CSPM is a key parameter describing case-II water quality. Empirical and semi-empirical models are frequently developed and applied for estimating CSPM values from remote sensing images; however, they are usually region- or season-dependent. This study aimed to develop a Moderate Resolution Imaging Spectroradiometer (MODIS-based retrieval model of CSPM for Poyang and Dongting Lake together. The 89 CSPM measurements in Poyang and Dongting Lake as well as their corresponding MODIS Terra images were used to calibrate CSPM retrieval models, and the calibration results showed that the exponential models of MODIS red band and red minus shortwave infrared (SWIR band at 1240 nm both explained about 76% of the variation of CSPM of Poyang and Dongting Lake together. When the two models were applied to the validation datasets, the results indicated that the exponential model of red band obtained more stable CSPM estimations with no bias at a significance level of 0.05 in both lakes. The MODIS red-band-based model achieved acceptable results for estimating CSPM in both Poyang and Dongting Lake, and it provided a foundation for obtaining comparable spatiotemporal information of CSPM, which will be helpful for comparing, understanding, managing, and protecting the two aquatic ecosystems.

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

    Directory of Open Access Journals (Sweden)

    Pei Shang


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

  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.

    material in the nearshore region and off Godavari. Distribution pattern of TSM indicates that it closely follows the circulation pattern during the study period (August-September 1976). Combustible organic matter varies from 5 to 80% and these compositional...

  16. The distribution of particulate material on Mars (United States)

    Christensen, Philip R.


    The surface materials on Mars were extensively studied using a variety of spacecraft and Earth-based remote sensing observations. These measurements include: (1) diurnal thermal measurements, used to determine average particle size, rock abundance, and the presence of crusts; (2) radar observations, used to estimate the surface slope distributions, wavelength scale roughness, and density; (3) radio emission observations, used to estimate subsurface density; (4) broadband albedo measurements, used to study the time variation of surface brightness and dust deposition and removal; and (5) color observations, used to infer composition, mixing, and the presence of crusts. Remote sensing observations generally require some degree of modeling to interpret, making them more difficult to interpret than direct observations from the surface. They do, however, provide a means for examining the surface properties over the entire planet and a means of sampling varying depths within the regolith. Albedo and color observations only indicate the properties of the upper-most few microns, but are very sensitive to thin, sometimes emphemeral dust coatings. Thermal observations sample the upper skin depth, generally 2 to 10 cm. Rock abundance measurements give an indirect indication of surface mantling, where the absence of rocks suggests mantles of several meters. Finally, radar and radio emission data can penetrate several meters into the surface, providing an estimate of subsurface density and roughness.

  17. Transport phenomena and drying of solids and particulate materials

    CERN Document Server

    Lima, AG


    The purpose of this book, Transport Phenomena and Drying of Solids and Particulate Materials, is to provide a collection of recent contributions in the field of heat and mass transfer, transport phenomena, drying and wetting of solids and particulate materials. The main benefit of the book is that it discusses some of the most important topics related to the heat and mass transfer in solids and particulate materials. It includes a set of new developments in the field of basic and applied research work on the physical and chemical aspects of heat and mass transfer phenomena, drying and wetting processes, namely, innovations and trends in drying science and technology, drying mechanism and theory, equipment, advanced modelling, complex simulation and experimentation. At the same time, these topics will be going to the encounter of a variety of scientific and engineering disciplines. The book is divided in several chapters that intend to be a resume of the current state of knowledge for benefit of professional c...

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

    Directory of Open Access Journals (Sweden)

    M. Staubwasser


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

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

    Directory of Open Access Journals (Sweden)

    Dong S. Ko


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

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

    DEFF Research Database (Denmark)

    Møhlenberg, F.; Kiørboe, Thomas


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

  1. 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


    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.

  2. Effects of riverine suspended particulate matter on post-dredging metal re-contamination across the sediment-water interface. (United States)

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


    Environmental dredging is often used in river mouth areas to remove heavy metals. However, following dredging, high levels of metal-adsorbed suspended particulate matter (SPM) originating from polluted inflowing rivers might adversely affect the sediment-water interface (SWI). Here, we conducted a 360-day-long experiment investigating whether the riverine SPM adversely affects dredging outcome in a bay area of Lake Chaohu, China. We found that the heavy metal concentrations in the post-dredging surface sediment increased to pre-dredging levels for all metals studied (As, Cd, Cr, Cu, Ni, Pb, and Zn) after the addition of SPM. In addition, the increased concentrations were mostly detected in the relatively bioavailable non-residual fractions. Of the metals studied, the rate of increase was the greatest for Zn and Cd (482.98% and 261.07%, respectively), mostly in the weak acid extractable fraction. These results were probably due to certain characteristics of SPM (fine grain size, and high concentrations of organic matter and heavy metals) and the good oxic conditions of the SWI. Furthermore, As was the only metal for which we observed an increasing trend of diffusive flux across the SWI. However, the flux was still significantly lower than that measured before dredging. In conclusion, the quantity and character of riverine metal-adsorbed SPM affect metal re-contamination across the post-dredging SWI, and this information should be incorporated into the management schemes of dredging projects dedicated to reducing metal contamination in similar areas. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. Airborne particulate soiling of terrestrial photovoltaic modules and cover materials (United States)

    Hoffman, A. R.; Maag, C. R.


    Results are presented for the first phase of a photovoltaic-module soiling study that was carried out with NASA participation to investigate the problem of the electrical performance degradation of flat-plate photovoltaic modules exposed at outdoor sites that is due to the accumulation of airborne particulates on sensitive optical surfaces. The results were obtained in both field and laboratory soiling experiments, as well as in materials field experiments using candidate encapsulants and top covers. It is concluded that: (1) the electrical performance degradation shows a significant time and site dependence, ranging from 2% to 60% power loss; (2) the rate of particulate accumulation appears to be largely material independent when natural removal processes do not dominate; (3) the effectiveness of natural removal processes, especially rain, is strongly material dependent; (4) top-cover materials of glass and plexiglass retain fewer particles than silicone rubber; and (5) high module voltages relative to ground do not appear to affect the rate of dirt accumulation on modules.

  4. Distributor means for charging particulate material into receptacles (United States)

    Greaves, Melvin J.


    Disclosed are receptacles, such as shaft furnaces illustrated by a blast furnace and an upright oil shale retort, embodying rotatable charge distributor means for distributing particulate charge material in the furnace, which charge distributor means can provide a high uniformity of distribution of various sizes of particles and also can provide and maintain a stock line of desired contour and heighth in the receptacle. The distributor means includes a hopper having rigidly fixed to it a plurality of downwardly extending chutes with lower discharge portions that discharge in concentric circular zones at the stock line. The distributor means includes a segmented portion at the juncture of the hopper and the chutes that divides the charge material discharged into the hopper in proportion to the area of the circular zone at the stock line that is fed by the chute. The distributor means embodies means for providing mass flow of the particulate charge material through the chutes to the stock line and for avoiding segregation between larger and smaller particles of charge material deposited at the stock line.

  5. Origins of suspended particulate matter based on sterol distribution in low salinity water mass observed in the offshore East China Sea. (United States)

    Kim, Moonkoo; Jung, Jee-Hyun; Jin, Yongnu; Han, Gi Myeong; Lee, Taehee; Hong, Sang Hee; Yim, Un Hyuk; Shim, Won Joon; Choi, Dong-Lim; Kannan, Narayanan


    The molecular composition and distribution of sterols were investigated in the East China Sea to identify the origins of suspended particulate matter (SPM) in offshore waters influenced by Changjiang River Diluted Water (CRDW). Total sterol concentrations ranged from 3200 to 31,900pgL(-1) and 663 to 5690pgL(-1) in the particulate and dissolved phases, respectively. Marine sterols dominated representing 71% and 66% in the particulate and dissolved phases, respectively. Typical sewage markers, such as coprostanol, were usually absent at ~250km offshore. However, sterols from allochthonous terrestrial plants were still detected at these sites. A negative relationship was observed between salinity and concentrations of terrestrial sterols in SPM, suggesting that significant amounts of terrestrial particulate matter traveled long distance offshore in the East China Sea, and the Changjiang River Diluted Water (CRDW) was an effective carrier of land-derived particulate organic matter to the offshore East China Sea. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Fluvial fluxes of water, suspended particulate matter, and nutrients and potential impacts on tropical coastal water Biogeochemistry: Oahu, Hawai'i (United States)

    Hoover, D.J.; MacKenzie, F.T.


    Baseflow and storm runoff fluxes of water, suspended particulate matter (SPM), and nutrients (N and P) were assessed in conservation, urban, and agricultural streams discharging to coastal waters around the tropical island of Oahu, Hawai'i. Despite unusually low storm frequency and intensity during the study, storms accounted for 8-77% (median 30%) of discharge, 57-99% (median 93%) of SPM fluxes, 11-79% (median 36%) of dissolved nutrient fluxes and 52-99% (median 85%) of particulate nutrient fluxes to coastal waters. Fluvial nutrient concentrations varied with hydrologic conditions and land use; land use also affected water and particulate fluxes at some sites. Reactive dissolved N:P ratios typically were ???16 (the 'Redfield ratio' for marine phytoplankton), indicating that inputs could support new production by coastal phytoplankton, but uptake of dissolved nutrients is probably inefficient due to rapid dilution and export of fluvial dissolved inputs. Particulate N and P fluxes were similar to or larger than dissolved fluxes at all sites (median 49% of total nitrogen, range 22-82%; median 69% of total phosphorus, range 49-93%). Impacts of particulate nutrients on coastal ecosystems will depend on how efficiently SPM is retained in nearshore areas, and on the timing and degree of transformation to reactive dissolved forms. Nevertheless, the magnitude of particulate nutrient fluxes suggests that they represent a significant nutrient source for many coastal ecosystems over relatively long time scales (weeks-years), and that reductions in particulate nutrient loading actually may have negative impacts on some coastal ecosystems.

  7. A photometric function for diffuse reflection by particulate materials (United States)

    Meador, W. E.; Weaver, W. R.


    A photometric function is proposed to describe the diffuse reflection of radiation by particulate materials. Both multiple scattering and the dominant effects of particle shadowing are included and the function is verified by comparisons with the photometries of laboratory surfaces. Brightness measurements of planetary and other diffusely scattering surfaces can be used to calculate the brightness for geometries other than those used in the measurements and for which the Minnaert function does not apply. The measurements also can be directly related to such surface characteristics as particle size, single-particle albedo, and compactness.

  8. Natural, anthropogenic and fossil organic matter in river sediments and suspended particulate matter: a multi-molecular marker approach. (United States)

    Micić, V; Kruge, M A; Köster, J; Hofmann, T


    Different classes of organic matter (OM) have been systematically investigated in sediments and suspended particulate matter (SPM) along the Danube River in order to understand causes of compositional changes. Analytical pyrolysis revealed the dominance of natural organic matter (NOM) in most of the samples. The predominance of aquatic biomass is evident mainly from the abundance of organonitrogen compounds and phenol distributions. As the river enters a forested gorge, the terrestrial component of the NOM in sediments is more significant. This is reflected in abundant methoxyphenols and a very high carbon preference index. SPM sample from a tributary shows a unique geochemical signature. It contains abundant carboxylic acids, amines, isoprenoids in the pyrolyzate, and is dominated by phytol and 24-methyl-cholesta-5,24(28)-dien-3β-ol in the extract, produced by a diatom bloom. Wax esters with a relatively high proportion of short, methyl-branched alkyl-chains appear together with abundant phytadienes and n-C(17) alkane in some samples, suggesting a microbial origin. Anthropogenic OM from runoff and atmospheric deposition was evident from a minor input of polycyclic aromatic hydrocarbons (PAHs) originating from mixed combustion sources. Multivariate analysis using PAH data led us to define simple molecular ratios to distinguish the PAH composition in sand and silty sediments. The newly defined ratios are the alkylated phenanthrenes and anthracenes ratio (APA; C(1)-C(3)/C(0)-C(3) phenanthrenes and anthracenes) and the PAH ring number ratio (RN; 5-6 ring parent PAHs/all parent PAHs). This demonstrates that alkylated, as well as 5-6 ring PAHs are better preserved in the finer than in coarser grained sediments. A ubiquitous, but minor input of petroleum-related contamination with a uniform composition was evident in all samples as revealed by the analysis of petroleum biomarkers. This study demonstrates that the investigation of different classes of riverine OM

  9. Effectiveness of dust control methods for crystalline silica and respirable suspended particulate matter exposure during manual concrete surface grinding. (United States)

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


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

  10. Dispersion of suspended material from an operating sand suction dredge in the Øresund (Denmark)

    DEFF Research Database (Denmark)

    Kiørboe, Thomas; Møhlenberg, F.


    The concentration of suspended material in the immediate vicinity of an operating sand suction dredge in the Oresund was 3-5000mg/l. Concentrations > 100 mg/l were restricted to a downstream distance of .apprx. 150m and ambient levels were reached within .apprx. 1 km of the dredge. The natural va...

  11. A new protocol for the analysis of pharmaceuticals, pesticides, and hormones in sediments and suspended particulate matter from rivers and municipal wastewaters. (United States)

    Darwano, Hicham; Duy, Sung Vo; Sauvé, Sébastien


    We developed a protocol to quantify 12 emerging contaminants (ECs) (pharmaceuticals and hormones) and pesticides extracted from suspended particulate matter (SPM) of river water and municipal wastewaters samples as well as river sediments. The separation of suspended solids was realized using filtration of water samples. We tested a series of six different filter types. The effect of filtration on the concentrations of dissolved contaminants was evaluated to minimize losses of target compounds. The river sediment samples were lyophilized, and both SPM and sediment samples were subjected to ultrasonic extraction combined with C18 cartridge clean-up. Quantifications were realized using mass spectrometry. The method recoveries of all compounds ranged from 38 to 112 % in all studied matrices; poorer recoveries were achieved for sulfamethoxazole and diclofenac (as low as 38 %), whereas the recoveries for all other compounds in the wastewater treatment plant (WWTP) samples were between 68 and 111 %. The detection limits in sediments and SPM from river samples for the 12 analytes varied from 0.7 to 9.4 ng g(-1) and from 21 to 92 ng g(-1) for WWTP SPM samples. All targeted ECs were detected with concentrations ranging from 3 to 5,440 ng g(-1) in the studied matrices with the highest concentrations observed in WWTP SPM samples. A significant portion of the contaminants in a water sample is clearly associated with the suspended particulates. Optimization of water-treatment processes and environmental fate must absolutely consider the fraction of contaminants that is particulate-bound if one hopes to have a reasonable mass balance.

  12. 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.

    suspended matter (TSM) into the continental margin of the SE Arabian Sea has been evaluated from subweekly synoptic variations in TSM and its advection rates, currents and winds during the southwest monsoon (SWM) and postmonsoon season. Our study endorses...

  13. Thermal conductivity measurements of particulate materials under Martian conditions (United States)

    Presley, M. A.; Christensen, P. R.


    The mean particle diameter of surficial units on Mars has been approximated by applying thermal inertia determinations from the Mariner 9 Infrared Radiometer and the Viking Infrared Thermal Mapper data together with thermal conductivity measurement. Several studies have used this approximation to characterize surficial units and infer their nature and possible origin. Such interpretations are possible because previous measurements of the thermal conductivity of particulate materials have shown that particle size significantly affects thermal conductivity under martian atmospheric pressures. The transfer of thermal energy due to collisions of gas molecules is the predominant mechanism of thermal conductivity in porous systems for gas pressures above about 0.01 torr. At martian atmospheric pressures the mean free path of the gas molecules becomes greater than the effective distance over which conduction takes place between the particles. Gas particles are then more likely to collide with the solid particles than they are with each other. The average heat transfer distance between particles, which is related to particle size, shape and packing, thus determines how fast heat will flow through a particulate material.The derived one-to-one correspondence of thermal inertia to mean particle diameter implies a certain homogeneity in the materials analyzed. Yet the samples used were often characterized by fairly wide ranges of particle sizes with little information about the possible distribution of sizes within those ranges. Interpretation of thermal inertia data is further limited by the lack of data on other effects on the interparticle spacing relative to particle size, such as particle shape, bimodal or polymodal mixtures of grain sizes and formation of salt cements between grains. To address these limitations and to provide a more comprehensive set of thermal conductivities vs. particle size a linear heat source apparatus, similar to that of Cremers, was assembled to

  14. 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.


    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

  15. Quantifying uncertainty in measurement of mercury in suspended particulate matter by cold vapor technique using atomic absorption spectrometry with hydride generator. (United States)

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


    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).

  16. Self-healing of damaged particulate materials through materials through sintering

    NARCIS (Netherlands)

    Luding, Stefan; Suiker, A.S.J.


    Particulate materials loaded under uniaxial compression and tension are studied using the discrete element method. Self-healing of the damaged samples is activated through sintering, a process that effectively increases the contact adhesion (i.e. the tensile strength) between particles. The initial

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

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


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

  18. Suspended material availability and filtration-biodeposition processes performed by a native and invasive bivalve species in streams (United States)

    Atkinson, C.L.; First, M.R.; Covich, A.P.; Opsahl, S.P.; Golladay, S.W.


    Unionid mussels are among the most threatened group of freshwater organisms globally. They are known for their ability to filter food particles from flowing and standing waters. However, invasive bivalve species, such as the Asian clam (Corbicula fluminea) in North America, have the potential to overlap in feeding and potentially out-compete the native species. Yet, the feeding preferences of unionid mussels and C. fluminea are incompletely understood. We hypothesized that Elliptio crassidens (native) and C. fluminea (invasive) would select for specific organic components present within seston. We examined changes in seston (dry mass and ash-free dry mass) resulting from bivalve feeding activity for three size classes of material that were isolated using gravimetric filtration. The treatments were also sub-sampled for flow cytometry (FC) which separated the suspended materials in the stream water into five categories: detritus, heterotrophic bacteria, picoautotrophs, nanoautotrophs, and heterotrophic nanoeukaryotes. Our results indicated that both species of bivalve showed preferences for organic and living materials. E. crassidens preferentially filtered nanoeukaryotes, whose decreases were associated with an increase in bacteria. In contrast, C. fluminea preferred smaller materials through selective filtration of picoautotrophs. In addition, both species increased the concentration of large materials toward the end of the experiment because of the suspension of their pseudofeces biodeposits. To our knowledge, this study is the first to examine grazing by bivalve species on natural stream particulate matter using FC. Our results suggest that native and non-native mussels have different functional roles, which has important implications for organic matter processing and food webs in streams. ?? 2011 Springer Science+Business Media B.V.

  19. High-Fidelity Micromechanics Model Enhanced for Multiphase Particulate Materials (United States)

    Pindera, Marek-Jerzy; Arnold, Steven M.


    This 3-year effort involves the development of a comprehensive micromechanics model and a related computer code, capable of accurately estimating both the average response and the local stress and strain fields in the individual phases, assuming both elastic and inelastic behavior. During the first year (fiscal year 2001) of the investigation, a version of the model called the High-Fidelity Generalized Method of Cells (HFGMC) was successfully completed for the thermo-inelastic response of continuously reinforced multiphased materials with arbitrary periodic microstructures (refs. 1 and 2). The model s excellent predictive capability for both the macroscopic response and the microlevel stress and strain fields was demonstrated through comparison with exact analytical and finite element solutions. This year, HFGMC was further extended in two technologically significant ways. The first enhancement entailed the incorporation of fiber/matrix debonding capability into the two-dimensional version of HFGMC for modeling the response of unidirectionally reinforced composites such as titanium matrix composites, which exhibit poor fiber/matrix bond. Comparison with experimental data validated the model s predictive capability. The second enhancement entailed further generalization of HFGMC to three dimensions to enable modeling the response of particulate-reinforced (discontinuous) composites in the elastic material behavior domain. Next year, the three-dimensional version will be generalized to encompass inelastic effects due to plasticity, viscoplasticity, and damage, as well as coupled electromagnetothermomechanical (including piezoelectric) effects.

  20. [Grain Size Distribution Characteristics of Suspended Particulate Matter as Influenced by the Apparent Pollution in the Eutrophic Urban Landscape Water Body]. (United States)

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


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

  1. Size-selective sampling performance of six low-volume “total” suspended particulate (TSP) inlets (United States)

    Several low-volume inlets (flow rates ≤ 16.7 liters per minute (Lpm)) are commercially available as components of low-cost, portable ambient particulate matter samplers. Because the inlets themselves do not contain internal fractionators, they are often assumed to representati...

  2. Pharmaceuticals in settleable particulate material in urban and non-urban waters. (United States)

    Lahti, Marja; Oikari, Aimo


    Wastewater treatment plants (WWTP) are important sources of settleable particulate material (SPM), heading to sediments with natural suspended solids. To date, there is little information about the fate of pharmaceuticals in sediment systems. In this study, the objective was to determine if pharmaceuticals are detected in SPM at locations near WWTPs or even in rural areas, thus being susceptible for sedimentation. SPM samples were collected from 10 sites in Finland, grouped as reference, rural and wastewater effluent sites. SPM collectors were placed about 35 cm above bottom for about 2 months during summer. After extraction, a set of 17 pharmaceuticals was analyzed. Several pharmaceuticals were detected in SPM accumulated at sites next to WWTPs. The concentration of citalopram was notably high (300-1350 ng g⁻¹ dw). Also bisoprolol and ciprofloxacin were detected at high concentrations (6-325 and 9-390 ng g⁻¹ dw, respectively). In contrast, none of the pharmaceuticals were detected from reference sites and only two were found from a single rural site. There is no previous information about the presence of pharmaceuticals in SPM. The results showed that pharmaceuticals are sorbed to particles in WWTP and nearby, eventually ending up in sediments. These results also indicate that pharmaceuticals are not markedly contaminating sediments of rural areas in Finland. Copyright © 2011 Elsevier Ltd. All rights reserved.

  3. Lateral acoustic wave resonator comprising a suspended membrane of low damping resonator material (United States)

    Olsson, Roy H.; El-Kady; , Ihab F.; Ziaei-Moayyed, Maryam; Branch; , Darren W.; Su; Mehmet F.,; Reinke; Charles M.,


    A very high-Q, low insertion loss resonator can be achieved by storing many overtone cycles of a lateral acoustic wave (i.e., Lamb wave) in a lithographically defined suspended membrane comprising a low damping resonator material, such as silicon carbide. The high-Q resonator can sets up a Fabry-Perot cavity in a low-damping resonator material using high-reflectivity acoustic end mirrors, which can comprise phononic crystals. The lateral overtone acoustic wave resonator can be electrically transduced by piezoelectric couplers. The resonator Q can be increased without increasing the impedance or insertion loss by storing many cycles or wavelengths in the high-Q resonator material, with much lower damping than the piezoelectric transducer material.

  4. Method of feeding particulate material to a fluidized bed (United States)

    Borio, Richard W.; Goodstine, Stephen L.


    A centrifugal spreader type feeder that supplies a mixture of particulate limestone and coal to the top of a fluidized bed reactor having a flow of air upward therethrough. Large particles of particulate matter are distributed over the upper surface of the bed to utilize the natural mixing within the bed, while fine particles are adapted to utilize an independent feeder that separates them from the large particles and injects them into the bed.

  5. Graphene-based structure, method of suspending graphene membrane, and method of depositing material onto graphene membrane (United States)

    Zettl, Alexander K.; Meyer, Jannik Christian


    An embodiment of a method of suspending a graphene membrane across a gap in a support structure includes attaching graphene to a substrate. A pre-fabricated support structure having the gap is attached to the graphene. The graphene and the pre-fabricated support structure are then separated from the substrate which leaves the graphene membrane suspended across the gap in the pre-fabricated support structure. An embodiment of a method of depositing material includes placing a support structure having a graphene membrane suspended across a gap under vacuum. A precursor is adsorbed to a surface of the graphene membrane. A portion of the graphene membrane is exposed to a focused electron beam which deposits a material from the precursor onto the graphene membrane. An embodiment of a graphene-based structure includes a support structure having a gap, a graphene membrane suspended across the gap, and a material deposited in a pattern on the graphene membrane.

  6. Thermal conductivity of particulate materials: A summary of measurements taken at the Marshall Space Flight Center (United States)

    Fountain, J. A.


    Thermal conductivity measurements of particulate materials in vacuum are presented in summary. Particulate basalt and soda lime glass beads of various size ranges were used as samples. The differentiated line heat source method was used for the measurements. A comprehensive table is shown giving all pertinent experimental conditions. Least-squares curve fits to the data are presented.

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

    Directory of Open Access Journals (Sweden)

    Roman Majchrowski


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

  8. Generalized Effective Medium Theory for Particulate Nanocomposite Materials

    Directory of Open Access Journals (Sweden)

    Muhammad Usama Siddiqui


    Full Text Available The thermal conductivity of particulate nanocomposites is strongly dependent on the size, shape, orientation and dispersion uniformity of the inclusions. To correctly estimate the effective thermal conductivity of the nanocomposite, all these factors should be included in the prediction model. In this paper, the formulation of a generalized effective medium theory for the determination of the effective thermal conductivity of particulate nanocomposites with multiple inclusions is presented. The formulated methodology takes into account all the factors mentioned above and can be used to model nanocomposites with multiple inclusions that are randomly oriented or aligned in a particular direction. The effect of inclusion dispersion non-uniformity is modeled using a two-scale approach. The applications of the formulated effective medium theory are demonstrated using previously published experimental and numerical results for several particulate nanocomposites.

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

    Directory of Open Access Journals (Sweden)

    Bogdan Woźniak


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

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

    DEFF Research Database (Denmark)

    Massicotte, Philippe; Stedmon, Colin; Markager, Stiig


    Fine submicron organic particles can represent an important fraction of the dissolved organic matter (DOM) pool in aquatic ecosystems and their optical properties differ from those normally considered dissolved (< 0.2 μm), which means that the choice of filter type/pore size can influence the lig...

  11. The effect of suspended particulate material on cyanobacteria--cyanophage interactions in liquid culture. (United States)

    Barnet, Y M; Daft, M J; Stewart, W D


    The effect of the lytic phage LPP-DUN1 on the cyanobacterium Plectonema boryanum has been investigated in batch and in continuous cultures in the presence and absence of silt. In batch culture Plectonema without added phage grew normally; the presence of phage caused rapid lysis of the cyanobacterium and the addition of silt prevented lysis by the phage. In continuous culture the numbers of cyanobacterial cells and phage particles oscillated in a reciprocal manner, but the addition of silt damped down the oscillations in Plectonema biomass without decreasing the numbers of phage particles isolated from the cultures. The presence of silt thus appears to protect the cyanobacterium from lysis by phage, although the total numbers of phage particles are relatively unaffected by the silt, at least in the short-term.

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

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


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

  13. Seasonal characteristics of water-soluble inorganic ions and carbonaceous aerosols in total suspended particulate matter at a rural semi-arid site, Kadapa (India). (United States)

    Begam, G Reshma; Vachaspati, C Viswanatha; Ahammed, Y Nazeer; Kumar, K Raghavendra; Reddy, R R; Sharma, S K; Saxena, Mohit; Mandal, T K


    To better understand the sources as well as characterization of regional aerosols at a rural semi-arid region Kadapa (India), size-resolved composition of atmospheric particulate matter (PM) mass concentrations was sampled and analysed. This was carried out by using the Anderson low-pressure impactor for a period of 2 years during March 2013-February 2015. Also, the variations of organic carbon (OC), elemental carbon (EC) and water-soluble inorganic ion components (WSICs) present in total suspended particulate matter (TSPM) were studied over the measurement site. From the statistical analysis, the PM mass concentration showed a higher abundance of coarse mode particles than the fine mode during pre-monsoon season. In contrast, fine mode particles in the PM concentration showed dominance over coarse mode particle contribution during the winter. During the post-monsoon season, the percentage contributions of coarse and fine fractions were equal, whereas during the monsoon, coarse mode fraction was approximately 26 % higher than the fine mode. This distinct feature in the case of fine mode particles during the studied period is mainly attributed to large-scale anthropogenic activities and regional prevailing meteorological conditions. Further, the potential sources of PM have been identified qualitatively by using the ratios of certain ions. A high sulphate (SO4) concentration at the measurement site was observed during the studied period which is caused by the nearby/surrounding mining activity. Carbon fractions (OC and EC) were also analysed from the TSPM, and the results indicated (OC/EC ratio of ~4.2) the formation of a secondary organic aerosol. At last, the cluster backward trajectory analyses were also performed at Kadapa for different seasons to reveal the origin of sources from long-range transport during the study period.

  14. The influence of air-suspended particulate concentration on the incidence of suicide attempts and exacerbation of schizophrenia (United States)

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


    The main objective of this study was to evaluate the role of the concentration of solid air-suspended particles (SSP) in the incidence of mental disorders. The study is based on 1,871 cases, registered in the Beer-Sheva Mental Health Center (BS-MHC) at Ben-Gurion University (Israel) during a 16-month period from 2001 to 2002; 1,445 persons were hospitalized due to exacerbation of schizophrenia (ICD-10: F20-F29) and 426 after committing a suicide attempt using a variety of means as coded in the ICD-10 (ICD-10: X60-X84). Pearson and Spearman test correlations were used; the statistical significance was tested at p 0.3, p 0.2). A trend towards positive correlation ( ρ > 0.2, p psychotic attack ( N PS ) in periods with dominant eastern winds (4-9 am, local time) has been observed, while in the afternoon and evening hours (1-8 pm local time) with dominant western winds, N C and N PS are not correlated (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.

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

    Directory of Open Access Journals (Sweden)

    Yuyun Chen


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

  16. N-alkanes and polycyclic aromatic hydrocarbons in total suspended particulates from the southeastern Tibetan Plateau: concentrations, seasonal variations, and sources. (United States)

    Chen, Yang; Cao, Junji; Zhao, Jing; Xu, Hongmei; Arimoto, Richard; Wang, Gehui; Han, Yongming; Shen, Zhenxing; Li, Guohui


    Sixty-two suspended particle (TSP) samples were collected from Lulang on the southeastern Tibetan Plateau from July 2008 and July 2009 to investigate the concentrations, seasonal variations, and sources of n-alkanes and polycyclic aromatic hydrocarbons (PAHs). Samples were analyzed using thermal-deposition gas chromatography mass spectrometry. The concentrations of particulate total n-alkanes ranged from 0.10 to 21.83 ng m(-3), with an annual mean of 1.25 ng m(-3); the PAHs ranged from 0.06 to 2.53, with a mean of 0.59 ng m(-3). Up to 70% of PAHs were 5- and 6-ring compounds. The n-alkanes and PAHs both showed higher concentrations in winter and lower concentrations in summer. Analyses of diagnostic ratios indicate that 6.4% to 58.9% (mean 24.9%) of the n-alkanes were from plant waxes. Source characterization studies, i.e. diagnostic ratio and positive factor matrix analysis, suggest that the PAHs were from biomass burning as well as from fossil fuel combustion. Backward trajectory analysis suggests that the biomass mass burning pollutants could be from South Asia and western China via long distance transport. The study contributes to a more comprehensive understanding of the concentrations, seasonal variations, and sources of n-alkanes and PAHs in a remote background area in Tibetan Plateau. © 2013. Published by Elsevier B.V. All rights reserved.

  17. Temporal variation of suspended particulate matter and turbulence in a high energy, tide-stirred, coastal sea: Relative contributions of resuspension and disaggregation (United States)

    Jago, C. F.; Jones, S. E.; Sykes, P.; Rippeth, T.


    Measurements of turbulence and suspended particulate matter (SPM) were measured over a 50 h period at a site in high tidal energy, mixed waters of the Irish Sea, NW European shelf. Turbulence parameters included both production (variance method from seabed ADCP) and dissipation (FLY profiler); SPM parameters included mass and volume concentrations and particle size (LISST 100 C). It is shown that the resultant SPM time series was due to a combination of time-varying turbulence at the measurement site and space-varying turbulence advecting through the site. Time asymmetry in turbulence at the site produced an asymmetric M 4 signal in SPM volume concentration due to resuspension and disaggregation of flocs at times of peak turbulent energy. In terms of mass, the disaggregation contribution was 43% as much as the resuspension contribution near the bed, and 20% as much integrated throughout the water column. There was aggregation of flocs at high and low slack waters but the largest flocs occurred at low slack waters. Space-varying ambient turbulence was responsible for a horizontal gradient in floc size with small and large flocs at the high and low ends of the gradient, respectively; this generated a M 2 signal in SPM properties. SPM concentrations and properties at any time resulted from combination of M 2 and M 4 variations which are responsible for the well-known twin peaks signature seen in transmissometer time series in tidal waters.

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

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


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

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

    Chen, Yuyun; Jia, Rui; Yang, Shengke


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

  20. Metal contents of phytoplankton and labile particulate material in the North Atlantic Ocean (United States)

    Twining, Benjamin S.; Rauschenberg, Sara; Morton, Peter L.; Vogt, Stefan


    Phytoplankton contribute significantly to global C cycling and serve as the base of ocean food webs. Phytoplankton require trace metals for growth and also mediate the vertical distributions of many metals in the ocean. We collected bulk particulate material and individual phytoplankton cells from the upper water column (leached to extract biogenic and potentially-bioavailable elements, and the remaining refractory material was digested in strong acids. The cruise track spanned several ocean biomes and geochemical regions. Particulate concentrations of metals associated primarily with lithogenic phases (Fe, Al, Ti) were elevated in surface waters nearest North America, Africa and Europe, and elements associated primarily with biogenic material (P, Cd, Zn, Ni) were also found at higher concentrations near the coasts. However metal/P ratios of labile particulate material were also elevated in the middle of the transect for Fe, Ni, Co, Cu, and V. P-normalized cellular metal quotas measured with synchrotron X-ray fluorescence (SXRF) were generally comparable to ratios in bulk labile particles but did not show mid-basin increases. Manganese and Fe ratios and cell quotas were higher in the western part of the section, nearest North America, and both elements were more enriched in bulk particles, relative to P, than in cells, suggesting the presence of labile oxyhydroxide particulate phases. Cellular Fe quotas thus did not increase in step with aeolian dust inputs, which are highest near Africa; these data suggest that the dust inputs have low bioavailability. Copper and Ni cell quotas were notably higher nearest the continental margins. Overall mean cellular metal quotas were similar to those measured in the Pacific and Southern Oceans except for Fe, which was approximately 3-fold higher in North Atlantic cells. Cellular Fe quotas are in-line with those measured in laboratory cultures at comparable Fe concentrations. Particulate Zn, Cu, Ni, and Co are primarily

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

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


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

  2. The relationship between Suspended Particulate Matter and Turbidity at a mooring station in a coastal environment: consequences for satellite-derived products

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    Madihah Jafar-Sidik


    Full Text Available From a data set of observations of Suspended Particulate Matter (SPM concentration, Turbidity in Formazin Turbidity Unit (FTU and fluorescence-derived chlorophyll-a at a mooring station in Liverpool Bay, in the Irish Sea, we investigate the seasonal variation of the SPM:Turbidity ratio. This ratio changes from a value of around 1 in winter (minimum in January–February to 2 in summer (maximum in May–June. This seasonal change can be understood in terms of the cycle of turbulence and of the phytoplankton population that affects the nature, shape and size of the particles responsible for the Turbidity. The data suggest a direct effect of phytoplankton on the SPM:Turbidity ratio during the spring bloom occurring in April and May and a delayed effect, likely due to aggregation of particles, in July and August. Based on the hypothesis that only SPM concentration varies, but not the mass-specific backscattering coefficient of particles bbp*, semi-analytical algorithms aiming at retrieving SPM from satellite radiance ignore the seasonal variability of bbp* which is likely to be inversely correlated to the SPM:Turbidity ratio. A simple sinusoidal modulation of the relationship between Turbidity and SPM with time helps to correct this effect at the location of the mooring. Without applying a seasonal modulation to bbp*, there is an underestimation of SPM in summer by the Ifremer semi-analytical algorithm (Gohin et al., 2015 we tested. SPM derived from this algorithm, as expected from any semi-analytical algorithm, appears to be more related to in situ Turbidity than to in situ SPM throughout the year.

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

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    Elodie Robert


    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

  4. Fusion of Landsat-8/OLI and GOCI Data for Hourly Mapping of Suspended Particulate Matter at High Spatial Resolution: A Case Study in the Yangtze (Changjiang Estuary

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    Yanqun Pan


    Full Text Available Suspended particulate matter (SPM concentrations ([SPM] in the Yangtze estuary, which has third-order bifurcations and four outlets, exhibit large spatial and temporal variations. Studying the characteristics of these variations in [SPM] is important for understanding sediment transport and pollutant diffusion in the estuary as well as for the construction of port and estuarine engineering structures. The 1-h revisit frequency of the Geostationary Ocean Color Imager (GOCI sensor and the 30-m spatial resolution of the Landsat 8 Operational Land Imager (L8/OLI provide a new opportunity to study the large spatial and temporal variations in the [SPM] in the Yangtze estuary. In this study, [SPM] images with a temporal resolution of 1 h and a spatial resolution of 30 m are generated through the product-level fusion of [SPM] data derived from L8/OLI and GOCI images using the Spatial and Temporal Adaptive Reflectance Fusion Model (STARFM. The results show that the details and accuracy of the spatial and temporal variations are maintained well in the [SPM] images that are predicted based on the fused images. Compared to the [SPM] observations at fixed field stations, the mean relative error (MRE of the predicted SPM is 17.7%, which is lower than that of the GOCI-derived [SPM] (27.5%. In addition, thanks to the derived high-resolution [SPM] with high spatiotemporal dynamic changes, both natural phenomena (dynamic variation of the maximum turbid zone and human engineering changes leading to the dynamic variability of SPM in the channel are observed.

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

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


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

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

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


    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.

  7. ESR signal intensity of quartz in the fine-silt fraction of riverbed sediments from the Yangtze River: a provenance tracer for suspended particulate matter (United States)

    Saito, Keita; Tada, Ryuji; Zheng, Hongbo; Irino, Tomohisa; Luo, Chao; He, Mengying; Wang, Ke; Suzuki, Yoshiaki


    The Asian summer monsoon exerts a strong influence on the hydrologic cycle in East Asia. Moreover, the distribution of heavy precipitation in the Yangtze River basin, which covers a large area of South China, is sensitive to changes in monsoon intensity. Thus, the paleo-distribution of heavy precipitation in the Yangtze basin is key in reconstructing the paleo-monsoon intensity. In this study, we established proxies for distinguishing sediments from the northwestern and southeastern parts of the Yangtze River basin, with the goal of using them to reconstruct the paleo-distribution of heavy precipitation in the basin based on changes in the provenance of detrital sediments, as determined using sediment records at the river mouth. The proxies included the electron spin resonance (ESR) signal intensity and the crystallinity index (CI) of quartz in modern riverbed sediments along the mainstream and tributaries of the Yangtze River. The data revealed that the fine-silt fraction of the sediments (which represents suspended particulate matter, SPM) from each major tributary can be distinguished on the basis of ESR signal intensity and CI values. The values for each tributary reflect the age and type of bedrock in the tributary basin and show distinct regional variations according to the distribution of geological blocks within the Yangtze basin. In addition, the analyzed ESR signal intensity and CI values of the fine-silt fraction of riverbed sediments below mainstream-tributary junctions agree well with values calculated according to a simple mixing model of SPM discharged from the tributaries and the mainstream.

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

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    Bing Han


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

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

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    Đorđević Amelija


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

  10. Particulate organic carbon and particulate humic material in the Arabian Sea

    Digital Repository Service at National Institute of Oceanography (India)

    Sardessai, S.; Sarma, V.V.S.S.; DileepKumar, M.

    more towards south indicating accumulation of humic material. In contrast, PHM occurred in north than in south in intermonsoon. The north south trends cloud be seen in POC and PHM along 64 degrees E in the Arabian Sea. The POC levels were lower...

  11. Mechanical, Spectroscopic and Micro-structural Characterization of Banana Particulate Reinforced PVC Composite as Piping Material

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    B. Dan-asabe


    Full Text Available A banana particulate reinforced polyvinyl chloride (PVC composite was developed with considerabley low cost materials having an overall light-weight and good mechanical properties for potential application as piping material. The specimen composite material was produced with the banana (stem particulate as reinforcement using compression molding. Results showed that density and elastic Modulus of the composite decreases and increases respectively with increasing weight fraction of the particulate reinforcement. The tensile strength increased to a maximum of 42 MPa and then decreased steadily. The composition with optimum mechanical property (42 MPa was determined at 8, 62 and 30 % formulation of banana stem particulates (reinforcement, PVC (matrix and Kankara clay (filler respectively with corresponding percentage water absorption of 0.79 %, Young’s Modulus of 1.3 GPa, flexural strength of 92 MPa and density of 1.24 g/cm3. Fourier Transform Infrared (FTIR analysis of the constituents showed identical bands within the range 4000–1000 cm-1 with renown research work. Scanning Electron Microscopy (SEM result showed fairly uniform distribution of constituents’ phases. X-Ray Fluorescence (XRF confirms the X-ray diffraction (XRD result of the presence of minerals of kaolinite, quartz, rutile and illite in the kaolin clay. Comparison with conventional piping materials showed the composite offered a price savings per meter length of 84 % and 25 % when compared with carbon steel and PVC material.

  12. Apparatus for handling micron size range particulate material (United States)

    Friichtenicht, J. F.; Roy, N. L. (Inventor)


    An apparatus for handling, transporting, or size classifying comminuted material was described in detail. Electrostatic acceleration techniques for classifying particles as to size in the particle range from 0.1 to about 100 microns diameter were employed.

  13. Transport and exchange of U-series nuclides between suspended material, dissolved load and colloids in rivers draining basaltic terrains (United States)

    Pogge von Strandmann, Philip A. E.; Burton, Kevin W.; Porcelli, Don; James, Rachael H.; van Calsteren, Peter; Gislason, Sigurður R.


    This study presents uranium and thorium concentrations and activity ratios for all riverine phases (bedload, suspended load, dissolved load and colloids) from basaltic terrains in Iceland and the Azores. Small basaltic islands, such as these, are thought to account for ~ 25% of CO2 consumed by global silicate weathering, and for ~ 45% of the flux of suspended material to the oceans. These data indicate that [U] and [Th] in the dissolved and colloidal fractions are strongly controlled by pH, and to a much lesser extent by levels of dissolved organic carbon (which are low in these environments). At high pH, basalt glass dissolution is enhanced, and secondary mineral formation (e.g. Fe-oxyhydroxides and allophane) is suppressed, resulting in high dissolved [U], and low colloidal [U] and [Th], indicating a direct chemical weathering control on elemental abundances. When the dissolved (234U/238U) activity ratio is >~1.3 (i.e. when physical weathering, groundwater contribution or soil formation are high), there is little isotope exchange between dissolved and colloidal fractions. At lower activity ratios, the dissolved load and colloids have indistinguishable activity ratios, suggesting that when chemical weathering rates are high, secondary clay formation is also high, and colloids rapidly adsorb dissolved U. Many of the suspended sediment samples have (234U/238U) activity ratios of > 1, which suggests that uptake of U onto the suspended load is important. Identical (230Th/232Th) in suspended, dissolved and colloidal samples suggests that Th, like U, is exchanged or sorbed rapidly between all riverine phases. This particle-reactivity, combined with poorly constrained contributions from groundwater and hydrothermal water, and short-term variations in input to soils (volcanic and glacial), suggests that U-series nuclides in riverine material from such basaltic terrains are unlikely to reflect steady state erosion processes.

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

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    Stéfani Novoa


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

  15. Using VIIRS/NPP and MODIS/Aqua data to provide a continuous record of suspended particulate matter in a highly turbid inland lake (United States)

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


    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 products obtained using MODIS/Aqua and VIIRS/NPP have a satisfactory degree of consistency (0-150 mg/L SPM: R2 = 0.81, UPD < 16% and 0-80 mg/L SPM: R2 = 0.85, UPD < 12%, respectively

  16. Mechanical properties of Al-mica particulate composite material (United States)

    Nath, D.; Bhatt, R. T.; Rohatgi, P. K.; Biswas, S. K.


    Cast aluminum alloy mica particle composites of varying mica content were tested in tension, compression, and impact. With 2.2 percent mica (size range 40-120 microns) the tensile and compression strengths of aluminum alloy decreased by 56 and 22 percent, respectively. The corresponding decreases in percent elongation and percent reduction are 49 and 39 percent. Previous work shows that despite this decrease in strength the composite with 2.5 percent mica and having an UTS of 15 kg/sq mm and compression strength of 28 kg/sq mm performs well as a bearing material under severe running conditions. The differences in strength characteristics of cast aluminum-mica particle composites between tension and compression suggests that, as in cast iron, expansion of voids at the matrix particle interface may be the guiding mechanism of the deformation. SEM studies show that on the tensile fractured specimen surface, there are large voids at the particle matrix interface.

  17. Materials in particulate form for tissue engineering. 2. Applications in bone. (United States)

    Silva, G A; Coutinho, O P; Ducheyne, P; Reis, R L


    Materials in particulate form have been the subjects of intensive research in view of their use as drug delivery systems. While within this application there are still issues to be addressed, these systems are now being regarded as having a great potential for tissue engineering applications. Bone repair is a very demanding task, due to the specific characteristics of skeletal tissues, and the design of scaffolds for bone tissue engineering presents several difficulties. Materials in particulate form are now seen as a means of achieving higher control over parameters such as porosity, pore size, surface area and the mechanical properties of the scaffold. These materials also have the potential to incorporate biologically active molecules for release and to serve as carriers for cells. It is believed that the combination of these features would create a more efficient approach towards regeneration. This review focuses on the application of materials in particulate form for bone tissue engineering. A brief overview of bone biology and the healing process is also provided in order to place the application in its broader context. An original compilation of molecules with a documented role in bone tissue biology is listed, as they have the potential to be used in bone tissue engineering strategies. To sum up this review, examples of works addressing the above aspects are presented. 2007 John Wiley & Sons, Ltd

  18. Conduction and Narrow Escape in Dense, Disordered, Particulate-based Heterogeneous Materials (United States)

    Lechman, Jeremy

    For optimal and reliable performance, many technological devices rely on complex, disordered heterogeneous or composite materials and their associated manufacturing processes. Examples include many powder and particulate-based materials found in phyrotechnic devices for car airbags, electrodes in energy storage devices, and various advanced composite materials. Due to their technological importance and complex structure, these materials have been the subject of much research in a number of fields. Moreover, the advent of new manufacturing techniques based on powder bed and particulate process routes, the potential of functional nano-structured materials, and the additional recognition of persistent shortcomings in predicting reliable performance of high consequence applications; leading to ballooning costs of fielding and maintaining advanced technologies, should motivate renewed efforts in understanding, predicting and controlling these materials' fabrication and behavior. Our particular effort seeks to understand the link between the top-down control presented in specific non-equilibrium processes routes (i.e., manufacturing processes) and the variability and uncertainty of the end product performance. Our ultimate aim is to quantify the variability inherent in these constrained dynamical or random processes and to use it to optimize and predict resulting material properties/performance and to inform component design with precise margins. In fact, this raises a set of deep and broad-ranging issues that have been recognized and as touching the core of a major research challenge at Sandia National Laboratories. In this talk, we will give an overview of recent efforts to address aspects of this vision. In particular the case of conductive properties of packed particulate materials will be highlighted. Combining a number of existing approaches we will discuss new insights and potential directions for further development toward the stated goal. Sandia National

  19. On the design of novel multifunctional materials by using particulate additives (United States)

    Dunnigan, Ross Daniel

    This thesis has been organized into five chapters. The main focus of this thesis is to design novel multifunctional materials by using particulate additives. Chapter 1 is devoted to reviewing recent studies in additive manufacturing (AM) and other background information. In Chapter 2, the synthesis and characterization of novel Ti3SiC2-reinforced Zn-matrix composites is reported. During this study, all the Zn composites were hot pressed at 500°C for 5 min at a uniaxial pressure of ~150 MPa. Microstructure analysis by SEM (Scanning Electron Microscopy) and phase analysis by XRD (X-ray Diffraction) confirmed that there was minimal interfacial reaction between Ti3SiC 2 particles and the Zn matrix. The addition of Ti3SiC 2 improved the tribological performance of these composites against alumina substrates but did not have any beneficial effect on the mechanical performance. The addition of Ti3SiC2 particulates to metal and polymer matrices show interesting properties. Chapter 3 will focus on additive manufacturing of Ti3SiC2 particulates in a polymer matrix. Waste materials are a big problem in the world. Chapters 4 and 5 focus on recycling materials. The mechanical and tribological properties of the Resin-Nylon and ResinPolyester composites are reported, respectively.

  20. Characterization of undigested particulate material following microwave digestion of recycled document papers. (United States)

    McGaw, Elizabeth A; Szymanski, David W; Smith, Ruth Waddell


    Recycled document paper was microwave digested in a solution of HNO(3) and H(2)O(2) prior to analysis by inductively coupled plasma mass spectrometry (ICP-MS) to determine the trace elemental concentrations within the paper. Undigested particulate material was observed and subsequently characterized as a mixture of kaolin (clay) and TiO(2) by Fourier transform infrared spectroscopy and X-ray diffraction spectroscopy. The effect of the particulate material on the elemental concentrations was then investigated. Paper samples were completely digested in hydrofluoric acid (HF) and element concentrations determined in the HF and HNO(3)/H(2)O digests were statistically compared using Student's t-test (95% confidence limit). Statistical differences in element concentrations between the two digests were observed for only four elements and there was no evidence of element adsorption by the particulate material. Hence, the HNO(3)/H(2)O(2) digestion proved sufficient to digest paper for ICP-MS analysis, eliminating the need to use the hazardous and corrosive HF matrix.

  1. 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.


    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.

  2. 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. (United States)

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


    Risk of chronic obstructive pulmonary disease symptoms due to long-term exposure to ambient levels of total suspended particulates (TSP) and sulfur dioxide (SO2) symptoms was ascertained using the National Heart, Lung, and Blood Institute (NHLBI) respiratory symptoms questionnaire on 7,445 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: SO2 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.

  3. Sedimentation of particulate material in stratified and nonstratified water columns in the Bombay high area of the Arabian sea

    Digital Repository Service at National Institute of Oceanography (India)

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

    Sedimentation of particulate material at 22, 42 and 62 m was recorded at a station in the Bombay High area of the Arabian Sea from September 1985 to March 1986. Diatom numbers and physical structure, especially thermal stratification, played...

  4. Method for removing solid particulate material from within liquid fuel injector assemblies (United States)

    Simandl, Ronald F.; Brown, John D.; Andriulli, John B.; Strain, Paul D.


    A method for removing residual solid particulate material from the interior of liquid fuel injectors and other fluid flow control mechanisms having or being operatively associated with a flow-regulating fixed or variable orifice. The method comprises the sequential and alternate introduction of columns of a non-compressible liquid phase and columns of a compressed gas phase into the body of a fuel injector whereby the expansion of each column of the gas phase across the orifice accelerates the liquid phase in each trailing column of the liquid phase and thereby generates turbulence in each liquid phase for lifting and entraining the solid particulates for the subsequent removal thereof from the body of the fuel injector.

  5. Assessing the origin of suspended particulate matter in the Rhône River from the geochemical signature of the particulate residual fraction and hydro-sedimentary numerical modelling (United States)

    Dabrin, Aymeric; Bretier, Marie; Dugué, Violaine; Masson, Matthieu; Le-Bescond, Chloé; Panay, Josselin; Le Coz, Jérôme; Coquery, Marina


    Suspended particulate matter (SPM) transport through rivers is a major vector for nutrient and pollutant fluxes to continental shelf areas. Since physico-chemical properties of SPM from each sub-catchment will determine pollutant reactivity, it is necessary to obtain relevant information on the origin of SPM, in order to apply effective strategies for sediment management. Fingerprinting approaches based on the concentrations of trace metals, rare earth elements, mineralogy or radionuclides, have been developed allowing identifying SPM at the sub-catchment scale. However, confounding factors such as non-conservative behavior and enrichment/depletion of elements during the sediment delivery process represent a main concern. In this way, few studies addressed SPM origin in large river systems from the upstream part to the coastal environment by applying multi-tracer signatures. This is probably due to evolution of non-conservative element signatures during transport linked to biogeochemical processes (e.g. organic matter degradation, flocculation, desorption). To avoid the problem of non-conservative element signatures, we propose a significant improvement of fingerprinting approaches based on the concentrations of major elements and trace metals measured in the residual (conservative) fraction of SPM. The aim of our study was to apply this original geochemical approach to the upper part of the Rhône River (France). This approach was used to estimate, at each given time in the Rhône River, the SPM inputs contribution of several sub-basins (Arve, Ain, Fier, Guiers and Bourbre rivers). The concentrations in the residual fraction were estimated by the difference of concentrations obtained after two different extraction methods on SPM (a total extraction by using a mixture of HN03, HCl and HF acids; and a soft extraction by applying only HCl 1M). By this method, we were able to determine a geochemical signature typical of each sub-basin which should be conservative in

  6. Acetalated dextran is a chemically and biologically tunable material for particulate immunotherapy. (United States)

    Broaders, Kyle E; Cohen, Joel A; Beaudette, Tristan T; Bachelder, Eric M; Fréchet, Jean M J


    Materials that combine facile synthesis, simple tuning of degradation rate, processability, and biocompatibility are in high demand for use in biomedical applications. We report on acetalated dextran, a biocompatible material that can be formed into microparticles with degradation rates that are tunable over 2 orders of magnitude depending on the degree and type of acetal modification. Varying the degradation rate produces particles that perform better than poly(lactic-co-glycolic acid) and iron oxide, two commonly studied materials used for particulate immunotherapy, in major histocompatibility complex class I (MHC I) and MHC II presentation assays. Modulating the material properties leads to antigen presentation on MHC I via pathways that are dependent or independent of the transporter associated with antigen processing. To the best of our knowledge, this is the only example of a material that can be tuned to operate on different immunological pathways while maximizing immunological presentation.

  7. A multi-material topology optimization approach for wrinkle-free design of cable-suspended membrane structures (United States)

    Luo, Yangjun; Niu, Yanzhuang; Li, Ming; Kang, Zhan


    In order to eliminate stress-related wrinkles in cable-suspended membrane structures and to provide simple and reliable deployment, this study presents a multi-material topology optimization model and an effective solution procedure for generating optimal connected layouts for membranes and cables. On the basis of the principal stress criterion of membrane wrinkling behavior and the density-based interpolation of multi-phase materials, the optimization objective is to maximize the total structural stiffness while satisfying principal stress constraints and specified material volume requirements. By adopting the cosine-type relaxation scheme to avoid the stress singularity phenomenon, the optimization model is successfully solved through a standard gradient-based algorithm. Four-corner tensioned membrane structures with different loading cases were investigated to demonstrate the effectiveness of the proposed method in automatically finding the optimal design composed of curved boundary cables and wrinkle-free membranes.

  8. Matrix changes and side effects induced by electrokinetic treatment of porous and particulate materials

    DEFF Research Database (Denmark)

    Skibsted, Gry

    of porous stone materials to hinder decay. However, in addition to the removal of target ions in these systems, matrix changes may occur during the electrochemical treatment. For a broader implementation of the electrokinetic methods it is important to understand changes in the matrix composition......Transport of ions in an applied electric field holds many applications within both civil and environmental engineering, e.g. for removal of chlorides from concrete to hinder reinforcement corrosion, remediation of heavy metals from soils and other waste materials and recently for desalination...... for different types of materials. The overall aim of this PhD-project is to evaluate matrix changes and side effects induced by electrokinetic treatment of porous and particulate materials.During electro-remediation protons are produced at the anode and hydroxyl ions are produced at the cathode. The consequent...

  9. Principal sources and dispersal patterns of suspended particulate matter in nearshore surface waters of the northeast Pacific Ocean and the Hawaiian Islands (United States)

    Carlson, P. R. (Principal Investigator)


    The author has identified the following significant results. ERTS-1 green and red band imagery supplemented by U-2 photographs provides synoptic views of turbid, nearshore, near-surface bodies of water which adds to the body of knowledge about the coastal ocean necessary for a thorough understanding of the dynamic environment. Tubidity and suspended sediment measurements made in the Gulf of the Farallones correlate well with water tonal patterns visible on satellite imagery. Three successively seaward zones of turbid water could be delineated. Secchi disc visibility tests were the most definitive, ranging from or = 2 meters in the main plume, to almost 3 meters in the second zone of turbid water, to 4 meters in the furthest seaward zone of turbid water measured. These variations in water clarity were reinforced by suspended sediment concentrations which ranged from 26-28 mg/1, to 20-24 mg/1, to 11-15 mg/1, respectively, in each of the three masses of water. Transmissiometer readings were basically in agreement with the suspended sediment and Secchi disc values measured. Satellite imagery and U-2 photographs of the California coastal zone taken early in April 1973 show numerous plumes of suspended sediment being deflected southward. This indicates a southward flow of the nearshore, near-surface waters, a reversal from that noted in January 1973.

  10. 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.

    by Parsons et al. (1984). In order to analyze δ13CPOC, and δ15NTPN, GF/F filters containing particulate material were treated with vapours of concentrated HCl to remove carbonates, and oven dried at 40 °C for 24 h (Hedges 6 and Stern, 1984). The bulk...

  11. Modern sampling and analytical methods for the determination of trace elements in marine particulate material using magnetic sector inductively coupled plasma-mass spectrometry. (United States)

    Bowie, Andrew R; Townsend, Ashley T; Lannuzel, Delphine; Remenyi, Tomas A; van der Merwe, Pier


    Trace elements often limit phytoplankton growth in the ocean, and the quantification of particulate forms is essential to fully understand their biogeochemical cycling. There is presently a lack of reliable measurements on the trace elemental content of marine particles, in part due to the inadequacies of the sampling and analytical methods employed. Here we report on the development of a series of state-of-the-art trace metal clean methods to collect and process oceanic particulate material in open-ocean and sea ice environments, including sampling, size-fractionated filtration, particle digestions and analysis by magnetic sector inductively coupled plasma-mass spectrometry (ICP-MS). Particular attention was paid to the analysis of certified reference materials (CRMs) and field blanks, which are typically the limiting factor for the accurate analysis of low concentrations of trace metals in marine particulate samples. Theoretical detection limits (3 s of the blank) were low for all 17 elements considered, and varied according to filter material and porosity (sub-microg L(-1) for polycarbonate filters and 1-2 microg L(-1) for quartz and polyester filters). Analytical accuracy was verified using fresh water CRMs, with excellent recoveries noted (93-103%). Digestion efficiencies for various acid combinations were assessed using sediment and plankton CRMs. Using nitric acid only, good recoveries (79-90%) were achieved for Mo, Cd, Ba, Pb, Mn, Fe, Co, Ni, Cu, Zn and Ga. The addition of HF was necessary for the quantitative recovery of the more refractory trace elements such as U, Al, V and Cr. Bioactive elements such as P can also be analysed and used as a biomass normaliser. Our developed sampling and analytical methods proved reliable when applied during two major field programs in both the open Southern Ocean and Antarctic sea ice environments during the International Polar Year in 2007. Trace elemental data are presented for particulate samples collected in both

  12. Particulate Filled Composite Plastic Materials from Recycled Glass Fibre Reinforced Plastics

    Directory of Open Access Journals (Sweden)

    Aare ARUNIIT


    Full Text Available Glass fibre reinforced plastic (GFRP scrap consisted of acrylic plastic with glass fibre reinforcement in polyester resin matrix was used in our experiments. The multi-functional DS-series disintegrator mills were used for mechanical processing of GFRP scrap. Preceding from the results characterization of the milled powder particles size, shape and other properties the numerical algorithm for modelling of the density of the new filler material was developed. The main goal of the current study is to develop new particulate filled composite plastic material from recycled GFRP scrap. With recovered plastic powder material the higher filler content in polyester resin matrix can be achieved. The new composite is modelled on basis of the properties of new material. Such an approach requires tests of the new material. The considered target characteristics of the new material are the tensile strength, elongation at break and the cost. The multicriteria optimization problem has been formulated and solved by use of physical programming techniques and Pareto optimality concept. The designed new composites were manufactured in different mixing ratios of powder and binder agent. The strength and stiffness properties of new composite material were tested.

  13. Optimizing the Advanced Ceramic Material (ACM) for Diesel Particulate Filter Applications

    Energy Technology Data Exchange (ETDEWEB)

    Dillon, Heather E.; Stewart, Mark L.; Maupin, Gary D.; Gallant, Thomas R.; Li, Cheng; Mao, Frank H.; Pyzik, Aleksander J.; Ramanathan, Ravi


    This paper describes the application of pore-scale filtration simulations to the ‘Advanced Ceramic Material’ (ACM) developed by Dow Automotive for use in advanced diesel particulate filters. The application required the generation of a three dimensional substrate geometry to provide the boundary conditions for the flow model. An innovative stochastic modeling technique was applied matching chord length distribution and the porosity profile of the material. Additional experimental validation was provided by the single channel experimental apparatus. Results show that the stochastic reconstruction techniques provide flexibility and appropriate accuracy for the modeling efforts. Early optimization efforts imply that needle length may provide a mechanism for adjusting performance of the ACM for DPF applications. New techniques have been developed to visualize soot deposition in both traditional and new DPF substrate materials. Loading experiments have been conducted on a variety of single channel DPF substrates to develop a deeper understanding of soot penetration, soot deposition characteristics, and to confirm modeling results.

  14. Spectral reflectance and emittance of particulate materials. I - Theory. II - Application and results (United States)

    Emslie, A. G.; Aronson, J. R.


    The sizes, shapes, and complex refractive indices of particles are calculated in a study of the IR spectral reflectance of a semiinfinite medium composed of irregular particles of different materials. Geometric optics techniques with corrections for additional absorption due to particle edges and asperities is used in scattering and absorption calculations for particles larger than the wavelength. A Lorentz-Lorenz model is used to derive the averaged complex index of the medium, assuming that its individual particles are ellipsoids. Experimental results obtained on a Michelson interferometer for the spectral emittance of particulate mineral materials are compared with theoretical results. Good agreement between the experimental and theoretical results suggests the applicability, in remote IR spectroscopy, of the theoretical concepts applied in this study.

  15. 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.

  16. The Applicability of the Distribution Coefficient, KD, Based on Non-Aggregated Particulate Samples from Lakes with Low Suspended Solids Concentrations. (United States)

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


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

  17. Principal sources and dispersal patterns of suspended particulate matter in nearshore surface waters of the northeast Pacific Ocean. [California coastal waters (United States)

    Carlson, P. R. (Principal Investigator); Janda, R. J.


    The author has identified the following significant results. Release-recovery paths of drift cards released in conjunction with ERTS-1 overflight show that nearshore surface currents along the central and northern California coast flowed southward at an average rate in excess of 10 cm/sec (8.5 km/day) during August and September 1973 (California Current). By the middle of October 1973, the nearshore surface currents had reversed and the dominant flow velocity was northward at an average rate in excess of 20 cm/sec (17 km/ day) (Davidson Current). The August-September data suggested the presence of counterclockwise gyres in Monterey Bay and the Gulf of the Farallones, but by the middle of October, the gyres were no longer evident. Imagery of April 1973 showed well developed plumes of suspended sediment in Monterey Bay from the Salinas River and in the Gulf of the Farallones from San Francisco Bay. ERTS-1 imagery provides an effective means of monitoring timber harvest in the redwood forest along the northern California coast. ERTS-1 imagery also clearly portrays contrasting topographic belts characterized by fluvial erosion and by mass movement. The most visually apparent and most persistent river mouth suspended sediment plumes are associated with those rivers that drain belts of topography that appear to have been eroded primarily by mass movement.

  18. Accident Generated Particulate Materials and Their Characteristics -- A Review of Background Information

    Energy Technology Data Exchange (ETDEWEB)

    Sutter, S. L.


    Safety assessments and environmental impact statements for nuclear fuel cycle facilities require an estimate of the amount of radioactive particulate material initially airborne (source term) during accidents. Pacific Northwest Laboratory (PNL) has surveyed the literature, gathering information on the amount and size of these particles that has been developed from limited experimental work, measurements made from operational accidents, and known aerosol behavior. Information useful for calculating both liquid and powder source terms is compiled in this report. Potential aerosol generating events discussed are spills, resuspension, aerodynamic entrainment, explosions and pressurized releases, comminution, and airborne chemical reactions. A discussion of liquid behavior in sprays, sparging, evaporation, and condensation as applied to accident situations is also included.

  19. Flux of particulate organic material from the euphotic zone of oceans: Estimation from phytoplankton biomass (United States)

    Legendre, Louis


    A major objective of modem biological oceanography is to quantify, model, and predict the downward flux of biogenic carbon. Previous papers have documented an empirical relationship between the sinking flux of particulate organic material from the euphotic zone (S) and phytoplankton biomass (B), in oceans, and suggested that S could be estimated directly from B. The present paper investigates, using a mathematical model and data from the literature, the relationship between S and B. Calculations show that S is determined mostly by B and also by p (instantaneous coefficient of net phytoplankton production minus euphotic zone heterotrophic community respiration and incorporation in the pelagic food web). The regression S = f(B) accounts for 90% of the variation in S. In remote sensing, B is derived from ocean color, phytoplankton production (P) is derived from B, and S is derived from P. Within that context, the biomass approach could be used as an additional means to constrain the estimates of S.

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

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


    A rapid and reliable analytical method was developed for the quantitative determination of psychopharmaceuticals, their precursors and by-products in real contaminated samples from a pharmaceutical company in Olomouc (Czech Republic), based on SPE disk extraction and detection by ultra performance liquid chromatography, combined with time-of-flight mass spectrometry. The target compounds were quantified in the real whole-water samples (water including suspended particles), both in the presence of suspended particulate matter (SPM) and high concentrations of other organic pollutants. A total of nine compounds were analyzed which consisted of three commonly used antidepressants (tricyclic antidepressants and antipsychotics), one antitussive agent and five by-products or precursors. At first, the SPE disk method was developed for the extraction of water samples (dissolved analytes, recovery 84-104%) and pressurised liquid extraction technique was verified for solid matrices (sludge samples, recovery 81-95%). In order to evaluate the SPE disk technique for whole water samples containing SPM, non contaminated groundwater samples were also loaded with different amounts (100 and 300mgL(-1)) of real contaminated sludge originating from the same locality. The recoveries from the whole-water samples obtained by SPE disk method ranged between 67 and 119% after the addition of the most contaminated sludge. The final method was applied to several real groundwater (whole-water) samples from the industrial area and high concentrations (up to 10(3)μgL(-1)) of the target compounds were detected. The results of this study document and indicate the feasibility of the SPE disk method for analysis of groundwater. Copyright © 2016 Elsevier B.V. All rights reserved.

  1. Spatial-time variability of particulate material content and its composition: From mesoscale to interannual variability (United States)

    Dudarev, Oleg; Charkin, Alexander; Semiletov, Igor; Gustafsson, Örjan; Vonk, Jorien; Sánchez-García, Laura


    The role of the coastal zone in lateral transport and fate of terrestrial organic carbon in the East Siberian Arctic Shelf (ESAS) has not been well studied to date because most recent activities have focused on onshore geomorphologic and geochemical features, while biogeochemical and sedimentation consequences of coastal erosion and riverine runoff into the sea were not studied sufficiently. Here we present the data obtained on joint Russian-US cruises (NOAA and NSF funded) in 2003, 2004, 2005, and in the International Siberian Shelf Study-2008 (ISSS-2008, supported by the Wallenberg Foundation, FEBRAS, NOAA, and the Russian NSF), which characterized a spatial and interannual variability in distribution of particulate material (PM), and its organic carbon and stable isotopes content. Dynamics and composition of PM were studied twice along the Lena River in summer-fall of 2003. Here, the spatial-time dynamics of PM composition (particulate organic carbon (POC), isotopes and mineralogical composition) is considered in connection with changing river runoff and wind patterns. It has been found that the dominant source of POC into the ESAS is coastal erosion, rather than input from the rivers (Lena, Yana, Indigirka, Kolyma). A sharp PM concentration gradient from "freshened/high PM" to "Pacific/low PM" waters was found across the frontal zone. The position of the frontal zone varies significantly from year to year; this difference is mainly attributed to the difference in atmospheric circulation patterns driving the Arctic Ocean circulation. During storms and surges the PM concentration in a single area was increased by 10 times or more (up to 80-242 mg/l) in 2000 and 2005 compared to the 2003 and 2004 PM concentration.

  2. Systematic Evaluation of Dissolved Lead Sorption Losses to Particulate Syringe Filter Materials (United States)

    Distinguishing between soluble and particulate lead in drinking water is useful in understanding the mechanism of lead release and identifying remedial action. Typically, particulate lead is defined as the amount of lead removed by a 0.45 µm filter. Unfortunately, there is little...

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

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


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

  4. Simple statistical formulas for estimating biogeochemical properties of suspended particulate matter in the southern Baltic Sea potentially useful for optical remote sensing applications* Financial support for this research was provided by Statutory Research Programme No. I.1 at the Institute of Oceanology, Polish Academy of Sciences, by research grant No. N N306 2838 33 awarded to Sławomir B. Woźniak by the Polish Ministry of Science and Higher Education, and by the ‘SatBałtyk’ project funded by the European Union through the European Regional Development Fund (contract No. POIG.01.01.02-22-011/09 entitled ‘The Satellite Monitoring of the Baltic Sea Environment’.

    Directory of Open Access Journals (Sweden)

    Sławomir B. Woźniak


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

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

    Directory of Open Access Journals (Sweden)

    Bogdan Woźniak


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

  6. 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.

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

  7. Neutral carbohydrate geochemistry of particulate material in the central equatorial Pacific (United States)

    Hernes, Peter J.; Hedges, John I.; Peterson, Michael L.; Wakeham, Stuart G.; Lee, Cindy

    Neutral carbohydrate compositions were determined for particulate samples from plankton net tows, shallow floating sediment traps, mid-depth and deep moored sediment traps, and sediment cores collected along a north-south transect in the central equatorial Pacific Ocean during the U.S. JGOFS EqPac program. Total neutral carbohydrate depth profiles and patterns along the transect follow essentially the same trends as bulk and organic carbon (OC) fluxes—attenuating with depth, high near the equator and decreasing poleward. OC-normalized total aldose (TCH 2,O) yields along the transect and with depth do not show any consitent patterns. Relative to a planktonic source, neutral carbohydrate compositions in sediment trap and sediment core samples reflect preferential loss of ribose and storage carbohydrates rich in glucose, and preferential preservation of structural carbohydrates rich in rhamnose, xylose, fucose, and mannose. There is also evidence for an intermediately labile component rich in galactose. It appears that compositional signatures of neutral carbohydrates in sediments are more dependent upon their planktonic source than on any particular diagenetic pathway. Relative to other types of organic matter, neutral carbohydrates are better preserved in calcareous oozes from 12°S to 5°N than in red clays at 9°N based on OC-normalized TCH 2O yields, due to either differing sources or sorption characteristics. Weight per cent glucose generally decreases with increased degradation of organic material in the central equatorial Pacific region. Based on weight per cent glucose, comparisons of samples between Survey I (El Niõn) and Survey II (non-El Niño) indicate that during Survey I, organic material in the epipelagic zone in the northern hemisphere may have undergone more degradation than organic material in the southern hemisphere.

  8. Development of two fine particulate matter standard reference materials (<4 μm and <10 μm) for the determination of organic and inorganic constituents. (United States)

    Schantz, Michele M; Cleveland, Danielle; Heckert, N Alan; Kucklick, John R; Leigh, Stefan D; Long, Stephen E; Lynch, Jennifer M; Murphy, Karen E; Olfaz, Rabia; Pintar, Adam L; Porter, Barbara J; Rabb, Savelas A; Vander Pol, Stacy S; Wise, Stephen A; Zeisler, Rolf


    Two new Standard Reference Materials (SRMs), SRM 2786 Fine Particulate Matter (Particulate Matter (particulate matter (PM). These materials have been characterized for the mass fractions of selected polycyclic aromatic hydrocarbons (PAHs), nitrated PAHs, brominated diphenyl ether (BDE) congeners, hexabromocyclododecane (HBCD) isomers, sugars, polychlorinated dibenzo-p-dioxin (PCDD) and dibenzofuran (PCDF) congeners, and inorganic constituents, as well as particle-size characteristics. These materials are the first Certified Reference Materials available to support measurements of both organic and inorganic constituents in fine PM. In addition, values for PAHs are available for RM 8785 Air Particulate Matter on Filter Media. As such, these SRMs will be useful as quality control samples for ensuring compatibility of results among PM monitoring studies and will fill a void to assess the accuracy of analytical methods used in these studies. Graphical Abstract Removal of PM from filter for the preparation of SRM 2786 Fine Particulate Matter.

  9. Chemical characteristics of particulate, colloidal, and dissolved organic material in Loch Vale Watershed, Rocky Mountain National Park (United States)

    McKnight, Diane M.; Harnish, R.; Wershaw, R. L.; Baron, J.S.; Schiff, S.


    The chemical relationships among particulate and colloidal organic material and dissolved fulvic acid were examined in an alpine and subalpine lake and two streams in Loch Vale Watershed, Rocky Mountain National Park. The alpine lake, Sky Pond, had the lowest dissolved organic carbon (DOC) (0.37 mgC/L), the highest particulate carbon (POC) (0.13 mgC/L), and high algal biomass. The watershed of Sky Pond is primarily talus slope, and DOC and POC may be autochthonous. Both Andrews Creek and Icy Brook gain DOC as they flow through wet sedge meadows. The subalpine lake, The Loch, receives additional organic material from the surrounding forest and had a higher DOC (0.66 mgC/L). Elemental analysis, stable carbon isotopic compositon, and 13C-NMR characterization showed that: 1) particulate material had relatively high inorganic contents and was heterogeneous in compositon, 2) colloidal material was primarily carbohydrate material with a low inorganic content at all sites; and 3) dissolved fulvic acid varied in compositon among sites. The low concentration and carbohydrate-rich character of the colloidal material suggests that this fraction is labile to microbial degradation and may be turning over more rapidly than particulate fractions or dissolved fulvic acid. Fulvic acid from Andrews Creek had the lowest N content and aromaticity, whereas Sky Pond fulvic acid had a higher N content and lower aromaticity than fulvic acid from The Loch. The UV-visible spectra of the fulvic acids demonstrate that variation in characteristics with sources of organic carbon can explain to some extent the observed nonlinear relationship between UV-B extinction coefficients and DOC concentrations in lakes.

  10. Method for contamination control and barrier apparatus with filter for containing waste materials that include dangerous particulate matter (United States)

    Pinson, Paul A.


    A container for hazardous waste materials that includes air or other gas carrying dangerous particulate matter has incorporated in barrier material, preferably in the form of a flexible sheet, one or more filters for the dangerous particulate matter sealably attached to such barrier material. The filter is preferably a HEPA type filter and is preferably chemically bonded to the barrier materials. The filter or filters are preferably flexibly bonded to the barrier material marginally and peripherally of the filter or marginally and peripherally of air or other gas outlet openings in the barrier material, which may be a plastic bag. The filter may be provided with a backing panel of barrier material having an opening or openings for the passage of air or other gas into the filter or filters. Such backing panel is bonded marginally and peripherally thereof to the barrier material or to both it and the filter or filters. A coupling or couplings for deflating and inflating the container may be incorporated. Confining a hazardous waste material in such a container, rapidly deflating the container and disposing of the container, constitutes one aspect of the method of the invention. The chemical bonding procedure for producing the container constitutes another aspect of the method of the invention.

  11. Geochemical Characterization of Rain Water Particulate Material on a Coastal Sub-Tropical Region in SE: Brazil

    Directory of Open Access Journals (Sweden)

    Silva Filho E.V.


    Full Text Available Airborne contamination has been of concern for a number of scientist in temperate regions. In the tropics, a very small amount of data is available. In this work, rain water particulate material was monitored in two sites in Rio de Janeiro State (Brazil: the first (Sepetiba, subjected to high inputs of metals from industrial activities and the second (Iguaba, subjected to very mild contamination. Particulate material was obtained by filtration of rain water samples. The filters were analysed by instrumental neutron activation analysis. The results show three important features: 1 the element enrichment patterns could be split into two groups, crustal and anthropogenic derived; 2 uniformity of element loads in rain water particles is observed; 3 enrichment of certain trace elements in airborne particles is probably an important source of contaminants to soils, sediments and the marine environment.

  12. Activation of Transient Receptor Potential Ankyrin-1 by Insoluble Particulate Material and Association with Asthma. (United States)

    Deering-Rice, Cassandra E; Shapiro, Darien; Romero, Erin G; Stockmann, Chris; Bevans, Tatjana S; Phan, Quang M; Stone, Bryan L; Fassl, Bernhard; Nkoy, Flory; Uchida, Derek A; Ward, Robert M; Veranth, John M; Reilly, Christopher A


    Inhaled irritants activate transient receptor potential ankyrin-1 (TRPA1), resulting in cough, bronchoconstriction, and inflammation/edema. TRPA1 is also implicated in the pathogenesis of asthma. Our hypothesis was that particulate materials activate TRPA1 via a mechanism distinct from chemical agonists and that, in a cohort of children with asthma living in a location prone to high levels of air pollution, expression of uniquely sensitive forms of TRPA1 may correlate with reduced asthma control. Variant forms of TRPA1 were constructed by mutating residues in known functional elements and corresponding to single-nucleotide polymorphisms in functional domains. TRPA1 activity was studied in transfected HEK-293 cells using allyl-isothiocynate, a model soluble electrophilic agonist; 3,5-ditert butylphenol, a soluble nonelectrophilic agonist and a component of diesel exhaust particles; and insoluble coal fly ash (CFA) particles. The N-terminal variants R3C and R58T exhibited greater, but not additive, activity with all three agonists. The ankyrin repeat domain-4 single nucleotide polymorphisms E179K and K186N exhibited decreased response to CFA. The predicted N-linked glycosylation site residues N747A and N753A exhibited decreased responses to CFA, which were not attributable to differences in cellular localization. The pore-loop residue R919Q was comparable to wild-type, whereas N954T was inactive to soluble agonists but not CFA. These data identify roles for ankyrin domain-4, cell surface N-linked glycans, and selected pore-loop domain residues in the activation of TRPA1 by insoluble particles. Furthermore, the R3C and R58T polymorphisms correlated with reduced asthma control for some children, which suggest that TRPA1 activity may modulate asthma, particularly among individuals living in locations prone to high levels of air pollution.

  13. Water absorption experimental analysis of an orange peel and coconut shell particulate blend reinforcement material for composite fabrication

    Directory of Open Access Journals (Sweden)

    Oluwaseyi Ayodele Ajibade


    Full Text Available The extant literature on composites has downplayed the merits of orange peel particulates (OPPs and coconut shell particulates (CSPs as fillers in mixed forms despite their engineering purposes. An OPP-CSP mixture can be used to suppress the weight disadvantage of CSPs, exploit the water resistance advantage of CSP, enhance the mechanical properties and improve the wear resistance of OPPs as a result of the oily secretions of the OPP. Launching a new research direction of mixed filler experiments, this work examines the water absorption properties of mixed OPPs-CSPs of up to 30 cm3 mixtures by volume, according to filler literature norms and previous sensitivity tests. A principal result is that the average free swell of the particulate blend increased up to 164.61%, a value attained with an initial volume of CSPs equal to 10 cm3 in a combined initial volume of 30 cm3. Thus, the mixing ratio is 10 CSPs:20 OPPs (Type I. This free swell value can cause considerable changes to loadings and structures, which is a negative outcome. Sensitivity analysis showed that the higher-OPPs-in-particulate blend produced the most favourable free swell values. In practice, the findings of this study meet the growing needs of the composite industry for materials having unusual combinations of the properties of water-resistance for lightweight applications in tennis rackets, household interior decorations and agricultural silos. This novel contribution pioneers efforts to produce filler blends of particulate orange peels and coconut shells in independently varied proportions rather than being embedded in composites. Sensitivity analysis of the critical process parameters was carried out to understand the degree of responsiveness of model parameters of the blends. This is the first time such information has been reported in the literature.

  14. Suspended microfluidics


    Casavant, Benjamin P.; Berthier, Erwin; Theberge, Ashleigh B.; Jean BERTHIER; Montanez-Sauri, Sara I.; Bischel, Lauren L.; Brakke, Kenneth; Hedman, Curtis J.; Bushman, Wade; Keller, Nancy P.; Beebe, David J.


    Although the field of microfluidics has made significant progress in bringing new tools to address biological questions, the accessibility and adoption of microfluidics within the life sciences are still limited. Open microfluidic systems have the potential to lower the barriers to adoption, but the absence of robust design rules has hindered their use. Here, we present an open microfluidic platform, suspended microfluidics, that uses surface tension to fill and maintain a fluid in microscale...

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

    NARCIS (Netherlands)

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


    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

  16. Microstructure Based Material-Sand Particulate Interactions and Assessment of Coatings for High Temperature Turbine Blades (United States)

    Murugan, Muthuvel; Ghoshal, Anindya; Walock, Michael; Nieto, Andy; Bravo, Luis; Barnett, Blake; Pepi, Marc; Swab, Jeffrey; Pegg, Robert Tyler; Rowe, Chris; hide


    Gas turbine engines for military/commercial fixed-wing and rotary wing aircraft use thermal barrier coatings in the high-temperature sections of the engine for improved efficiency and power. The desire to further make improvements in gas turbine engine efficiency and high power-density is driving the research and development of thermal barrier coatings and the effort of improving their tolerance to fine foreign particulates that may be contained in the intake air. Both commercial and military aircraft engines often are required to operate over sandy regions such as in the Middle-East nations, as well as over volcanic zones. For rotorcraft gas turbine engines, the sand ingestion is adverse during take-off, hovering near ground, and landing conditions. Although, most of the rotorcraft gas turbine engines are fitted with inlet particle separators, they are not 100 percent efficient in filtering fine sand particles of size 75 microns or below. The presence of these fine solid particles in the working fluid medium has an adverse effect on the durability of turbine blade thermal barrier coatings and overall performance of the engine. Typical turbine blade damages include blade coating wear, sand glazing, Calcia-Magnesia-Alumina-Silicate (CMAS) attack, oxidation, plugged cooling holes, all of which can cause rapid performance deterioration including loss of aircraft. The objective of this research is to understand the fine particle interactions with typical ceramic coatings of turbine blades at the microstructure level. A finite-element based microstructure modeling and analysis has been performed to investigate particle-surface interactions, and restitution characteristics. Experimentally, a set of tailored thermal barrier coatings and surface treatments were down-selected through hot burner rig tests and then applied to first stage nozzle vanes of the Gas Generator Turbine of a typical rotorcraft gas turbine engine. Laser Doppler velocity measurements were performed

  17. 23 Elemental Composition of Suspended Particulate Matter ...

    African Journals Online (AJOL)


    vaseline oil to reduce particles bouncing off. The PM10 inlet was placed at a height of two metres above the ground for the first seven months and four metres for five months. Two polycarbonate nuclepore filters in sequence were used, both of 47mm diameter. These were coarse (8μm pore) and fine (0.4μm pore) diameter to ...

  18. Elemental Composition of Suspended Particulate Matter Collected ...

    African Journals Online (AJOL)

    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 samples collected at two metres and 50% of the samples collected at four metres height exceeded the WHO 24 guideline of 70μg m-3. Reduction in ...

  19. Particulate Composite Materials: Numerical Modeling of a Cross-Linked Polymer Reinforced With Alumina-Based Particles (United States)

    Máša, B.; Náhlík, L.; Hutař, P.


    The macroscopic mechanical properties of a particulate composite under uniaxial tensile loading have been estimated. The composite studied consisted of a polymer matrix in a rubbery state (polymethylmethacrylate - PMMA) and alumina-based particles (Al2O3). A numerical modeling by using the finite-element method (FEM) was performed to determine the stress-strain behavior of the particulate composite. The numerical simulation took into account the hyperelastic properties of the cross-linked polymer matrix, which was described by the three-parameter Mooney-Rivlin material model. A representative volume element (RVE) was chosen for FE analyses to model the microstructure of the composite. Various compositions of particles and their different shape and orientation were considered in the study. Various directions of loading of the RVE were also investigated. A progressive damage model was implemented into the numerical models. The mechanical characteristics obtained from computations, which included the damage model, were compared with experimental data, and a good agreement has been found to exist between them. The procedure presented can be used for estimating the mechanical properties of new particulate composites with a cross-linked polymer matrix, and it also contributes to the clarification of damage development and failure in composites of the type studied.

  20. Distribution and partitioning of aliphatic hydrocarbons and polycyclic aromatic hydrocarbons between water, suspended particulate matter, and sediment in harbours of the West coastal of the Gulf of Tunis (Tunisia). (United States)

    Mzoughi, Nadia; Chouba, Lassaad


    Harbours of La Goulette, Rades and Sidi Bou Said are considered as the principal largest and most important port in the Gulf of Tunis characterised by a direct influence of different activities (sailing, industry and fishing) to the Mediterranean Sea. Due to their social and economic impact, a comprehensive assessment of the spatial distribution and partitioning of 24 polycyclic aromatic hydrocarbons (PAHs) and 18 aliphatic hydrocarbons (AHs) in summer and in winter among overlying water, suspended particulate matter (SPM) and surface sediments is essential. Distribution of hydrophobic organic contaminants in abiotic compartments is important for describing their transfer and fate in aquatic ecosystems and to identify the potential danger due to mobilization of contaminants produced by managing of the same sediments. Total organic carbon (TOC) contents range between 4.3% and 6.5%, with an average value of 5.9% in summer, and between 2.3% and 9.6%, with an average value of 6.1% in winter. The average concentrations of ΣPAH in winter and in summer were respectively 703.1 ng L⁻¹ and 378.4 ng L⁻¹ in seawater, 4599.1 ng g⁻¹ and 3114 ng g⁻¹ in SPM, and 1507.6 ng g⁻¹ dw (dry weight) and 1294.6 ng g⁻¹ dw in surface sediment. For ΣAH the average concentrations in winter and in summer were respectively 701 ng L⁻¹ and 741.7 ng L⁻¹ in seawater, 6743.5 ng g⁻¹ and 6282.9 ng g⁻¹ in SPM, and 4971.3 ng g⁻¹ and 4588.1 ng g⁻¹ in surface sediment. Higher PAH and AH concentrations were observed in SPM than in surface sediment. SPM and water were dominated by PAH with low molecular weight, while for sediment low and high molecular weight PAHs were present. PAH and AH fingerprint ratios, such as pristane to phytane (Pr/Ph), phenanthrene to anthracene (Phe/An) and fluoranthene to pyrene (Fl/Py), suggest that hydrocarbons in all harbours may originate from both pyrolytic and petrogenic sources derived from discharge of untreated sewage and wastewater

  1. 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 (United States)

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


    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

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

    Digital Repository Service at National Institute of Oceanography (India)

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

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

  3. Role of mechanical compression on bone regeneration around a particulate bone graft material: an experimental study in rabbit calvaria. (United States)

    Romanos, Georgios E; Delgado-Ruiz, Rafael A; Gómez-Moreno, Gerardo; López-López, Patricia J; Mate Sanchez de Val, Jose E; Calvo-Guirado, Jose Luis


    This experimental study was designed to analyze the effect of different compressive forces on the bone regeneration around a particulate bone graft material. Eighty 6-mm-diameter defects were created in the calvaria of 20 New Zealand rabbits (4 defects per rabbit calvaria). All the defects were filled with particles of synthetic bone. Two standardized compressive forces were then applied, 4.1 g to half the defects (Test A) and 8.2 g to the other half (Test B), all for 1 min. The graft sites were allowed to heal for 6 weeks, after which the rabbits were euthanized. The calvarium vault of each animal was extracted, radiographed, and prepared for histomorphometric analysis. The percentage of defect fill, bone density, new bone formation, and residual bone graft material were recorded, and the results were subjected to statistical analysis. Histological evaluation found that defect closure among the Test A (lower compression) group ranged from 38.34 (95% lower CI) to 55.8 (95% upper CI) (mean 47 ± 8.5%), while among the Test B group (higher compression), it ranged from 81.26 (95% lower CI) to 95.32 (mean 88 ± 7.3%). Significantly more closure was achieved for the Test B group (P particulate used to fill small defects created in rabbit calvaria appears to be beneficial. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  4. 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.


    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


    Directory of Open Access Journals (Sweden)

    S. T. Antipov


    Full Text Available The technical task of the process is to improve the drying quality of the final product, increasing the precision and reliability of control, the reduction of specific energy consumption. One of the ways to improve the process is complex and i ts local automation. This paper deals with the problems of development and creation of a new control algorithm drying process of the particulate material. Identified a number of shortcomings of the existing methods of automatic control of the process. As a result, the authors proposed a method for drying particulate materials in the device with swirling flow and the microwave energy supply and its automatic control algorithm. The description of the operating principle of the drying apparatus consists in that the particulate material is wet by using a tangential flow of coolant supplied to the cylinder-drying apparatus which also serves the axial coolant flow, whereby the heat transfer fluid with the particulate material begins to undergo a complex circular movement along the circumference apparatus, thereby increasing its speed and its operation control algorithm. The work of this scheme is carried out at three levels of regulation on the basis of determining the coefficient of efficiency of the dryer, which makes it possible to determine the optimal value of the power equipment and to forecast the cost of electricity. All of the above allows you to get ready for a high quality product while minimizing thermal energy and material costs by optimizing the operating parameters of the drying of the particulate material in the dryer with a combined microwave energy supply and ensure the rational use of heat energy by varying their quantity depending on the characteristics to be dried particulate material and the course of the process.

  6. Retrospective trend analysis of the content of U. K. air particulate material 1957--1974

    Energy Technology Data Exchange (ETDEWEB)

    Salmon, L.; Atkins, D.H.F.; Fisher, E.M.R.; Healy, C.; Law, D.V.


    Particulate air samples have been collected on a daily basis in a high volume air sampler at Chilton (Oxfordshire U.K.) a semi-rural site in southern England from 1957 to 1974. Although the samples collected on esparto grass filters were intended to measure debris from nuclear weapons, they have proved susceptible to analysis for a variety of inorganic elements and ions. The concentration of twenty-seven elements and ions have been determined by instrumental neutron activation analysis and other methods. Measurements were performed on three-monthly groups of samples over seventeen years. Comparison with another series of current measurements over the latter part of the period indicate that the results are probably valid and thus, may represent the longest period for which continuous data of this nature are available. The detailed results are presented here.

  7. Organic particulate material levels in the atmosphere: conditions favoring sensitivity to varying relative humidity and temperature. (United States)

    Pankow, James F


    This study examines the sensitivity in predicted levels of atmospheric organic particulate matter (M(o), microg m(-3)) as those levels may potentially be affected by changes in relative humidity and temperature. In a given system, for each partitioning compound, f(g) and f(p) represent the gaseous and particulate fractions (f(g) + f(p) = 1). Sensitivity in the M(o) levels becomes dampened as the compounds contributing significantly to M(o) are increasingly found in the particle phase (f(p) --> 1). Thus, although local maxima in sensitivity can be encountered as M(o) levels increase, because as M(o) increases each f(p) --> 1, then increasing M(o) levels generally tend to reduce sensitivity in M(o) levels to changes in relative humidity and temperature. Experiments designed to elucidate the potential magnitudes of the effects of relative humidity and temperature on M(o) levels must be carried out at M(o) levels that are relevant for the ambient atmosphere: The f(p) values for the important partitioning compounds must not be elevated above ambient-relevant values. Systems in which M(o) levels are low (e.g., 1-2 microg m(-3)) and/or composed of unaged secondary organic aerosol are the ones most likely to show sensitivity to changing relative humidity and temperature. Results from two published chamber studies are examined in the above regard: [Warren B, et al. (2009) Atmos Environ 43:1789-1795] and [Prisle NL, et al. (2010) Geophys Res Lett 37:L01802].

  8. Analytical methods in bioassay-directed investigations of mutagenicity of air particulate material. (United States)

    Marvin, Christopher H; Hewitt, L Mark


    The combination of short-term bioassays and analytical chemical techniques has been successfully used in the identification of a variety of mutagenic compounds in complex mixtures. Much of the early work in the field of bioassay-directed fractionation resulted from the development of a short-term bacterial assay employing Salmonella typhimurium; this assay is commonly known as the Ames assay. Ideally, analytical methods for assessment of mutagenicity of any environmental matrix should exhibit characteristics including high capacity, good selectivity, good analytical resolution, non-destructiveness, and reproducibility. A variety of extraction solvents have been employed in investigations of mutagenicity of air particulate; sequential combination of dichloromethane followed by methanol is most popular. Soxhlet extraction has been the most common extraction method, followed by sonication. Attempts at initial fractionation using different extraction solvents have met with limited success and highlight the need for fractionation schemes applicable to moderately polar and polar mutagenic compounds. Fractionation methods reported in the literature are reviewed according to three general schemas: (i) acid/base/neutral partitioning followed by fractionation using open-column chromatography and/or HPLC; (ii) fractionation based on normal-phase (NP) HPLC using a cyanopropyl or chemically similar stationary phase; and (iii) fractionation by open-column chromatography followed by NP-HPLC. The HPLC methods may be preparative, semi-preparative, or analytical scale. Variations based on acid/base/neutral partitioning followed by a chromatographic separation have also been employed. Other lesser-used approaches involve fractionation based on ion-exchange and thin-layer chromatographies. Although some of the methodologies used in contemporary studies of mutagenicity of air particulate do not represent significant advances in technology over the past 30 years, their simplicity, low

  9. Climate induced variability of suspended matter and nutrient in the discharge of Kali river, central west coast of India

    Digital Repository Service at National Institute of Oceanography (India)

    Raghavan, B.R.; Chauhan, O.S.

    elevations above the riverbed following the methodology of Stern et al. (1986, 1991). Suspended particulate matter in the river water is estimated at 10 stations. The collection time in the estuarine samples was mid-tide synchronous during August..., in Manual and Guides 29, Paris, Scientific 9 committee on oceanic research, pp. 170. Stern, M. K., Jr. J. W. Day, and K. G. Teague (1986), Seasonality of materials transport through a coastal freshwater marsh: riverine versus tidal forcing...

  10. Reactivity, interactions and transport of trace elements, organic carbon and particulate material in a mountain range river system (Adour River, France). (United States)

    Point, David; Bareille, Gilles; Amouroux, David; Etcheber, Henri; Donard, Olivier F X


    The background levels, variability, partitioning and transport of eleven trace elements-Ag, Al, As, Cd, Co, Cr, Cu, Mn, Pb, Zn and U-were investigated in a mountain range river system (Adour River, France). This particular river system displayed a turbulent hydrodynamic regime, characterized by flash-transient discharge conditions leading to fast shifts in suspended particulate matter (SPM) concentrations as high as two orders of magnitude (12 to 600 mg l(-1)). The distribution of SPM was accurately predicted with a "hysteresis" transport model, indicating that about 75% of the annual solids load was exported within 20 to 40 days. Dissolved and particulate concentrations of most trace elements were low compared to their concentrations in other reference river systems expect for Pb and Cr, associated with historical anthropogenic activities. Although dissolved and particulate metal concentrations were steady for most elements during low and average discharge conditions, significant changes were observed with increasing river discharge. The changes in trace element concentrations in the two compartments was found to induce a partitioning anomaly referred to as the particulate concentration effect. This anomaly was significant for Cr, Mn, Pb, Zn, Cu and organic carbon (p < 0.03). The processes driving this anomaly were possibly linked to the modification and/or increase of colloidal organic and inorganic vectors, suggested by the significant increase of DOC (p < 0.001) and dissolved Al concentrations (p < 0.05) during flood conditions. A complementary process linked to the influence of coarse particles of low complexation capacity and transported mainly during high discharge may also effect trace element concentrations. Annual metal fluxes transported by this river system were estimated using the hysteresis SPM model with consideration of these fate processes. Metals in the Adour River system are primarily exported into the Bay of Biscay (Atlantic Ocean).

  11. Determination of optical parameters for light penetration in particulate materials and soils with diffuse reflectance (DR) spectroscopy. (United States)

    Schober, L; Löhmannsröben, H G


    The results of our investigations of particulate materials (aluminium oxide, quartz sand) and "real world" soils (a brown sand and a dark brown soil) using diffuse reflectance (DR) spectroscopy are presented. The findings are discussed within the framework of Kubelka-Munk (KM) theory as a simplified description of light propagation in highly turbid media. The relation between the KM and the Lambert-Beer (LB) treatment is outlined. The KM parameters determined were the scattering and absorption coefficients (S and K, respectively), and the light penetration depths, dp(KM). It was found that in the UV/VIS spectral range the scattering coefficients of the materials investigated vary by ca. one order of magnitude (S = 6-> 100 cm-1), whereas the absorption coefficients change by more than three orders of magnitude (K = 1500 cm-1). The different absorption and scattering properties of the materials lead to strong variations in light penetration depths from the micron into the mm regime [dp(KM) = 3500 microns].

  12. Materials selection and evaluation of Copper-Tungsten particulate composites for extreme electrical contacts (United States)

    Watkins, Bobby Gene, II


    Materials for extreme electrical contacts need to have high electrical conductivity coupled with good structural properties. Potential applications include motor contacts, high power switches, and the components of electromagnetic launch (EML) systems. The lack of durability experienced with these contact materials limits service life. Due to extreme current densities coupled with the local sliding, electrical contact surfaces can degrade due to a one or more wear mechanisms, including adhesive wear and thermally-assisted wear associated with extreme local Joule heating. A systematic materials selection procedure was developed to identify and compare candidate materials that would be more durable for these types of applications. The most promising materials identified on the Pareto frontier are tungsten alloys. Moreover, several possible candidate monolithic materials as well as hybrid materials that could potentially be even better, filling the "white spaces" on the material property charts, were identified. A couple of these potential candidate materials were obtained and evaluated. These included copper-tungsten W-Cu, "self-lubricating" graphite-impregnated Cu, and Gr-W-Cu composites with different volume fractions of the constituents. The structure-property relations were determined through mechanical and electrical resistivity testing. A unique test protocol for exposing mechanical test specimens to extreme current densities up to 1.2 GA/m2 was developed and used to evaluate these candidate materials. The design of materials including optimizing the microstructure attributes for these applications can potentially be accelerated by using micromechanics modeling and other materials design tools coupled with systematic mechanical and tribological experiments. In this study, physics- and micromechanics-based models were used to correlate properties to the volume fraction of the tungsten. These properties included elastic modulus, hardness, tensile strength, and

  13. Selecting optimal monitoring site locations for peak ambient particulate material concentrations using the MM5-CAMx4 numerical modelling system. (United States)

    Sturman, Andrew; Titov, Mikhail; Zawar-Reza, Peyman


    Installation of temporary or long term monitoring sites is expensive, so it is important to rationally identify potential locations that will achieve the requirements of regional air quality management strategies. A simple, but effective, numerical approach to selecting ambient particulate matter (PM) monitoring site locations has therefore been developed using the MM5-CAMx4 air pollution dispersion modelling system. A new method, 'site efficiency,' was developed to assess the ability of any monitoring site to provide peak ambient air pollution concentrations that are representative of the urban area. 'Site efficiency' varies from 0 to 100%, with the latter representing the most representative site location for monitoring peak PM concentrations. Four heavy pollution episodes in Christchurch (New Zealand) during winter 2005, representing 4 different aerosol dispersion patterns, were used to develop and test this site assessment technique. Evaluation of the efficiency of monitoring sites was undertaken for night and morning aerosol peaks for 4 different particulate material (PM) spatial patterns. The results demonstrate that the existing long term monitoring site at Coles Place is quite well located, with a site efficiency value of 57.8%. A temporary ambient PM monitoring site (operating during winter 2006) showed a lower ability to capture night and morning peak aerosol concentrations. Evaluation of multiple site locations used during an extensive field campaign in Christchurch (New Zealand) in 2000 indicated that the maximum efficiency achieved by any site in the city would be 60-65%, while the efficiency of a virtual background site is calculated to be about 7%. This method of assessing the appropriateness of any potential monitoring site can be used to optimize monitoring site locations for any air pollution measurement programme. Copyright © 2010 Elsevier B.V. All rights reserved.

  14. Improving suspended sediment measurements by automatic samplers. (United States)

    Gettel, Melissa; Gulliver, John S; Kayhanian, Masoud; DeGroot, Gregory; Brand, Joshua; Mohseni, Omid; Erickson, Andrew J


    Suspended solids either as total suspended solids (TSS) or suspended sediment concentration (SSC) is an integral particulate water quality parameter that is important in assessing particle-bound contaminants. At present, nearly all stormwater runoff quality monitoring is performed with automatic samplers in which the sampling intake is typically installed at the bottom of a storm sewer or channel. This method of sampling often results in a less accurate measurement of suspended sediment and associated pollutants due to the vertical variation in particle concentration caused by particle settling. In this study, the inaccuracies associated with sampling by conventional intakes for automatic samplers have been verified by testing with known suspended sediment concentrations and known particle sizes ranging from approximately 20 μm to 355 μm under various flow rates. Experimental results show that, for samples collected at a typical automatic sampler intake position, the ratio of sampled to feed suspended sediment concentration is up to 6600% without an intake strainer and up to 300% with a strainer. When the sampling intake is modified with multiple sampling tubes and fitted with a wing to provide lift (winged arm sampler intake), the accuracy of sampling improves substantially. With this modification, the differences between sampled and feed suspended sediment concentration were more consistent and the sampled to feed concentration ratio was accurate to within 10% for particle sizes up to 250 μm.

  15. Changes in toxicity and Ah receptor agonist activity of suspended particulate matter during flood events at the rivers Neckar and Rhine - a mass balance approach using in vitro methods and chemical analysis. (United States)

    Wölz, Jan; Engwall, Magnus; Maletz, Sibylle; Olsman Takner, Helena; van Bavel, Bert; Kammann, Ulrike; Klempt, Martin; Weber, Roland; Braunbeck, Thomas; Hollert, Henner


    As a consequence of flood events, runoff and remobilized sediments may cause an increase of ecotoxicologically relevant effects from contaminant reservoirs. Aquatic and terrestrial organisms as well as cattle and areas of settlement are exposed to dislocated contaminants during and after flood events. In this study, the impacts of two flood events triggered by intense rain at the rivers Neckar and Rhine (Southern Germany) were studied. Effects in correlation to flood flow were assessed at the river Neckar using samples collected at frequent intervals. River Rhine suspended particulate matter (SPM) was sampled over a longer period at normal flow and during a flood event. Three cell lines (H4L1.1c4, GPC.2D.Luc, RTL-W1) were used to compare Ah receptor agonist activity in different biotest systems. Multilayer fractionation was performed to identify causative compounds, focusing on persistent organic contaminants. Native water and SPM of flood events were collected at the river Neckar and at the monitoring station (Rheinguetestation, Worms, Germany) of the river Rhine. Water samples were XAD-extracted. SPM were freeze-dried and Soxhlet-extracted using acetone and finally dissolved in dimethyl sulfoxide. Resulting crude extracts were analyzed for cytotoxicity with the neutral red assay. Aryl hydrocarbon receptor (AhR) agonist activity was measured in a set of biological test systems (DR-CALUX, GPC.2D, and ethoxyresorufin-O-deethylase (EROD) assay) and different cell lines. In addition, crude extracts were fractionated using a combined method of multilayer (sequence of acidified silica layers) and carbon fractionation. Fractions from the multilayer fractionation contained persistent organic compounds (polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), polychlorinated biphenyls (PCBs), and some polycyclic aromatic hydrocarbon (PAHs)); fractions from the carbon fractionation were separated into a PCDD/F and a PCB fraction. Dioxin-like activity of multilayer and

  16. Wind sorting affects differently the organo-mineral composition of saltating and particulate materials in contrasting texture agricultural soils (United States)

    Iturri, Laura Antonela; Funk, Roger; Leue, Martin; Sommer, Michael; Buschiazzo, Daniel Eduardo


    There is little information about the mineral and organic composition of sediments eroded by wind at different heights. Because of that, wind tunnel simulations were performed on four agricultural loess soils of different granulometry and their saltating materials collected at different heights. The particulate matter with an aerodynamic diameter mainly smaller than 10 μm (PM10) of these soils was obtained separately by a laboratory method. Results indicated that the granulometric composition of sediments collected at different heights was more homogeneous in fine- than in sandy-textured soils, which were more affected by sorting effects during wind erosion. This agrees with the preferential transport of quartz at low heights and of clay minerals at greater heights. SOC contents increased with height, but the composition of the organic materials was different: stable carboxylic acids, aldehydes, amides and aromatics were preferentially transported close to the ground because their were found in larger aggregates, while plant debris and polysaccharides, carbohydrates and derivatives of microbial origin from organic matter dominated at greater heights for all soil types. The amount of SOC in the PM10 fraction was higher when it was emitted from sandy than from fine textured soils. Because of the sorting process produced by wind erosion, the stable organic matter compounds will be transported at low heights and local scales, modifying soil fertility due to nutrient exportation, while less stable organic compounds will be part of the suspension losses, which are known to affect some processes at regional- or global scale.

  17. Microfabricated suspended island platform for the measurement of in-plane thermal conductivity of thin films and nanostructured materials with consideration of contact resistance. (United States)

    Alaie, Seyedhamidreza; Goettler, Drew F; Abbas, Khawar; Su, Mehmet F; Reinke, Charles M; El-Kady, Ihab; Leseman, Zayd C


    A technique based on suspended islands is described to measure the in-plane thermal conductivity of thin films and nano-structured materials, and is also employed for measurements of several samples with a single measurement platform. Using systematic steps for measurements, the characterization of the thermal resistances of a sample and its contacts are studied. The calibration of the contacts in this method is independent of the geometry, size, materials, and uniformity of contacts. To verify the technique, two different Si samples with different thicknesses and two samples of the same SiN(x) wafer are characterized on a single device. One of the Si samples is also characterized by another technique, which verifies the current results. Characterization of the two SiN(x) samples taken from the same wafer showed less than 1% difference in the measured thermal conductivities, indicating the precision of the method. Additionally, one of the SiN(x) samples is characterized and then demounted, remounted, and characterized for a second time. The comparison showed the change in the thermal resistance of the contact in multiple measurements could be as small as 0.2 K/μW, if a similar sample is used.

  18. Method for depositing a uniform layer of particulate material on the surface of an article having interconnected porosity (United States)

    Wrenn, Jr., George E.; Lewis, Jr., John


    The invention is a method for depositing liquid-suspended particles on an immersed porous article characterized by interconnected porosity. In one form of the invention, coating is conducted in a vessel containing an organic liquid supporting a colloidal dispersion of graphite sized to lodge in surface pores of the article. The liquid comprises a first volatile component (e.g., acetone) and a second less-volatile component (e.g., toluene) containing a dissolved organic graphite-bonding agent. The liquid also contains an organic agent (e.g., cellulose gum) for maintaining the particles in suspension. A porous carbon article to be coated is immersed in the liquid so that it is permeated therewith. While the liquid is stirred to maintain a uniform blend, the vessel headspace is evacuated to effect flashing-off of the first component from the interior of the article. This causes particle-laden liquid exterior of the article to flow inwardly through its surface pores, lodging particles in these pores and forming a continuous graphite coating. The coated article is retrieved and heated to resin-bond the graphite. The method can be used to form a smooth, adherent, continuous coating of various materials on various porous articles. The method is rapid and reproducible.

  19. Head-of-tide bottleneck of particulate material transport from watersheds to estuaries (United States)

    Ensign, Scott H.; Noe, Gregory; Hupp, Cliff R.; Skalak, Katherine


    We measured rates of sediment, C, N, and P accumulation at four floodplain sites spanning the nontidal through oligohaline Choptank and Pocomoke Rivers, Maryland, USA. Ceramic tiles were used to collect sediment for a year and sediment cores were collected to derive decadal sedimentation rates using 137Cs. The results showed highest rates of short- and long-term sediment, C, N, and P accumulation occurred in tidal freshwater forests at the head of tide on the Choptank and the oligohaline marsh of the Pocomoke River, and lowest rates occurred in the downstream tidal freshwater forests in both rivers. Presumably, watershed material was mostly trapped at the head of tide, and estuarine material was trapped in oligohaline marshes. This hydrologic transport bottleneck at the head of tide stores most available watershed sediment, C, N, and P creating a sediment shadow in lower tidal freshwater forests potentially limiting their resilience to sea level rise.

  20. Thermal desorption GC-MS as a tool to provide PAH certified standard reference material on particulate matter quartz filters. (United States)

    Grandesso, Emanuela; Pérez Ballesta, Pascual; Kowalewski, Konrad


    Reference materials for particulate matter (PM) on filter media are not available for the quantification of polycyclic aromatic hydrocarbons (PAHs) in ambient air. This is due to the difficulty of obtaining reference material that has a homogeneous distribution on a filter surface that is large enough for characterization and distribution. High volume sample filters from different locations and seasons were considered to validate the feasibility of the use of quartz filters as reference material for PAH concentrations. A rapid thermal desorption (TD) technique coupled with gas chromatography/mass spectroscopy was applied to characterise the material for the content of fifteen different PAHs. TD technique allowed for rapid and accurate analysis of small sections of filter (5mm diameter), leaving enough material for the production of twenty sub-filter cuts (42 mm diameter) that could be used for distribution and control. Stability and homogeneity tests required for material certification were performed as indicated by the ISO guide 34:2009 and ISO 35:2006. The contribution of the heterogeneous distribution of PAHs on the filter surface resulted generally lower than 10% and higher for more volatile PAHs. One year of storage at -18°C indicated no significant variation in PAH concentrations. Nevertheless, a methodology for shipping and storing of the filter material at ambient temperature in especially designed plastic envelopes, was also shown to allow for stabile concentrations within twenty days. The method accuracy was confirmed by the analysis of NIST SRM 1649a (urban dust) and PAH concentrations were validated against the reference values obtained from an inter-laboratory exercise. In the case of benzo[a]pyrene for masses quantified between 100 pg and 10 ng the TD method provided expanded uncertainties of circa 10%, while the inter-laboratory reference value uncertainties ranged between 15 and 20%. The evaluation of these results supports the use of the presented

  1. 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.


    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)

  2. Vertical fluxes of particulate biogenic material through the euphotic and twilight zones in the Cariaco Basin, Venezuela (United States)

    Montes, Enrique; Muller-Karger, Frank; Thunell, Robert; Hollander, David; Astor, Yrene; Varela, Ramón; Soto, Inia; Lorenzoni, Laura


    Surface-tethered particle interceptor traps (PITs) were deployed at 50 and 100 m (1-3 days) on ten occasions in the Cariaco Basin between March 2007 and November 2009 to measure the settling fluxes of biogenic particles at 50 m (the base of the euphotic zone—Ez) and 100 m. Fluxes at these two depths were compared to concurrent fluxes estimated with moored sediment traps at 150, 225 and 410 m from the CARIACO Ocean Time-Series program. We measured particulate organic carbon (POC), particulate organic nitrogen (PON), calcium carbonate, biogenic silica and terrigenous material concentrations in samples collected with both the drifting and moored traps. We also estimated the fluxes of foraminifera shells and coccolithophore cells at 50 and 100 m using drifting traps samples. Surface chlorophyll a and primary production observations during each sampling period were examined to quantify the relationship between the magnitude and geochemical composition of the vertical flux and overlying production. Surface chlorophyll a concentrations and primary production rates were highest during months of upwelling (2.58-1.35 mg m-3 and 3.6-1.4 g C m-2 d-1, respectively). The fluxes of POC, PON, calcite and silica measured during the upwelling season (December-May) were typically higher than during the period of non-upwelling (August-November), when surface waters are more strongly stratified. POC fluxes measured with the drifting traps (50 and 100 m) varied between 0.95 (upwelling) and 0.14 g m-2 d-1 (non-upwelling), compared with those from the moored traps (150, 225 and 410 m) which ranged from 0.21 to 0.01 g m-2 d-1. Similarly, the fluxes of biogenic opal in the upper 100 m ranged from 1.12 and 0.18 g m-2 d-1, and those at greater depths varied from 0.27 g m-2 d-1 during upwelling to values near zero during stratification periods. The fluxes of POC, PON, calcite and silica in the upper 100 m decreased by an order of magnitude at the depth of the oxic-anoxic interface (>200 m

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

    Digital Repository Service at National Institute of Oceanography (India)

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

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

  4. Transient receptor potential vanilloid-1 (TRPV1) is a mediator of lung toxicity for coal fly ash particulate material. (United States)

    Deering-Rice, Cassandra E; Johansen, Mark E; Roberts, Jessica K; Thomas, Karen C; Romero, Erin G; Lee, Jeewoo; Yost, Garold S; Veranth, John M; Reilly, Christopher A


    Environmental particulate matter (PM) pollutants adversely affect human health, but the molecular basis is poorly understood. The ion channel transient receptor potential vanilloid-1 (TRPV1) has been implicated as a sensor for environmental PM and a mediator of adverse events in the respiratory tract. The objectives of this study were to determine whether TRPV1 can distinguish chemically and physically unique PM that represents important sources of air pollution; to elucidate the molecular basis of TRPV1 activation by PM; and to ascertain the contributions of TRPV1 to human lung cell and mouse lung tissue responses exposed to an insoluble PM agonist, coal fly ash (CFA1). The major findings of this study are that TRPV1 is activated by some, but not all of the prototype PM materials evaluated, with rank-ordered responses of CFA1 > diesel exhaust PM > crystalline silica; TRP melastatin-8 is also robustly activated by CFA1, whereas other TRP channels expressed by airway sensory neurons and lung epithelial cells that may also be activated by CFA1, including TRPs ankyrin 1 (A1), canonical 4α (C4α), M2, V2, V3, and V4, were either slightly (TRPA1) or not activated by CFA1; activation of TRPV1 by CFA1 occurs via cell surface interactions between the solid components of CFA1 and specific amino acid residues of TRPV1 that are localized in the putative pore-loop region; and activation of TRPV1 by CFA1 is not exclusive in mouse lungs but represents a pathway by which CFA1 affects the expression of selected genes in lung epithelial cells and airway tissue.

  5. Curcumin inhibits activation induced by urban particulate material or titanium dioxide nanoparticles in primary human endothelial cells. (United States)

    Montiel-Dávalos, Angélica; Silva Sánchez, Guadalupe Jazmin; Huerta-García, Elizabeth; Rueda-Romero, Cristhiam; Soca Chafre, Giovanny; Mitre-Aguilar, Irma B; Alfaro-Moreno, Ernesto; Pedraza-Chaverri, José; López-Marure, Rebeca


    Curcumin has protective effects against toxic agents and shows preventive properties for various diseases. Particulate material with an aerodynamic diameter of ≤10 μm (PM10) and titanium dioxide nanoparticles (TiO2-NPs) induce endothelial dysfunction and activation. We explored whether curcumin is able to attenuate different events related to endothelial activation. This includes adhesion, expression of adhesion molecules and oxidative stress induced by PM10 and TiO2-NPs. Human umbilical vein endothelial cells (HUVEC) were treated with 1, 10 and 100 μM curcumin for 1 h and then exposed to PM10 at 3 μg/cm2 or TiO2-NPs at 10 μg/cm2. Cell adhesion was evaluated by co-culture with U937 human myelomonocytic cells. Adhesion molecules expression was measured by flow cytometry after 3 or 24 h of exposure. Oxidative stress was determined by 2,7-dichlorodihydrofluorescein (H2DCF) oxidation. PM10 and TiO2-NPs induced the adhesion of U937 cells and the expression of E- and P-selectins, intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1) and platelet-endothelial cell adhesion molecule-1 (PECAM-1). The expression of E- and P-selectins matched the adhesion of monocytes to HUVEC after 3 h. In HUVEC treated with 1 or 10 μM curcumin, the expression of adhesion molecules and monocytes adhesion was significantly diminished. Curcumin also partially reduced the H2DCF oxidation induced by PM10 and TiO2-NPs. Our results suggest an anti-inflammatory and antioxidant role by curcumin attenuating the activation caused on endothelial cells by exposure to particles. Therefore, curcumin could be useful in the treatment of diseases where an inflammatory process and endothelial activation are involved.

  6. 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.

    slations from the Arabian Sea and analysed for suspended matter (SM) and particulate organic carbon (POC). Microfouling material from aluminium panels at the same stations was analysed for dry weight andior organic carbon. Microfouling biomass (as dry... the SM of the seawater and the dry weight of microfouling material (r=0·84;P~O·OOI).as well as between the poe of the seawater and the organic carbon of the fouling material (r=0·74 and 0·84;P~O·(}OI).Microfouling biomass on aluminium panels in deep...

  7. Nd-Sr isotopic compositions of dissolved and particulate material transported by the Parana and Uruguay rivers during high (december 1993) and low (september 1994) water periods; Compositions isotopiques de Nd et Sr des matieres en suspension et dissoutes transportees par les fleuves Parana et Uraguay en periodes de hautes (decembre 1993) et basses (septembre 1994) eaux

    Energy Technology Data Exchange (ETDEWEB)

    Henry, F.; Thouron, D.; Garcon, V. [Centre National de la Recherche Scientifique (CNRS), 31 - Toulouse (France); Henry, F. [Universite du Litoral, 62 - Wimereux (France). Laboratoire de Chimie Analytique appliquee a l' Environnement Naturel; Probst, J.L. [Universidad Nacional, Cordoba (Argentina). Facultad de Ciencias Exactas, Fisicas y Naturales


    Our motivation is to better constrain the neodymium and strontium isotopic signatures of the closest continental riverine source (Parana and Uruguay rivers) to the Brazil/Malvinas Confluence zone in the Southwest Atlantic Ocean. We thus present new isotopic data on the Nd and Sr of the dissolved and suspended loads of the Parana and Uruguay rivers for two water periods forming the Rio de la Plata whose drainage basin is the second largest one in South America. The Parana dissolved material shows less radiogenic ({epsilon}{sub Nd} (0) ranging between -12.1 and -8.2) than the Uruguay one with a mean {epsilon}{sub Nd} (0) value of -6.3 {+-} 0.3. Suspended particulates display the same isotopic trend (mean {epsilon}{sub Nd} (0) value of -10.3 and -6.0 for the Parana and Uruguay rivers, respectively). Dissolved load {sup 87}Sr/{sup 86}Sr in the Parana (0.7123) is found to be more radiogenic than the Uruguay one (0.7097); the suspended load follows the same trend with {sup 87}Sr/{sup 86}Sr ratios of 0.7247 and 0.7115 in the Parana and Uruguay rivers, respectively. The relatively radiogenic Nd and non radiogenic Sr of the Uruguay River as compared to the Parana River could be attributed to a predominance of tholeiitic basalts in the drainage basin. A revisited estimation of the fluxes of Nd considering all South American rivers delivering into the western South and Tropical Atlantic Ocean yields a Nd particulate flux to estuarine water two orders of magnitude higher than the Nd dissolved flux. Considering the net dissolved and suspended fluxes of Nd reaching the Rio de la Plata, we have calculated a resulting {epsilon}{sub Nd} (0) equal to -10.2. The computation of {epsilon}{sub Nd} (0) of the Rio de la Plata outflow waters gives a value of -8.3, taking into account various removal processes within the estuary. (authors)

  8. Activation of Human Transient Receptor Potential Melastatin-8 (TRPM8) by Calcium-Rich Particulate Materials and Effects on Human Lung Cells. (United States)

    Lamb, John G; Romero, Erin G; Lu, Zhenyu; Marcus, Seychelle K; Peterson, Hannah C; Veranth, John M; Deering-Rice, Cassandra E; Reilly, Christopher A


    To better understand how adverse health effects are caused by particulate materials, and to develop preventative measures, it is important to identify the properties of particles and proteins that link exposure with specific biological outcomes. Coal fly ash (CFA) is a by-product of coal combustion that can affect human health. Here we show that human transient receptor potential melastatin-8 (TRPM8) and an N-terminally truncated TRPM8 variant (TRPM8-Δ801) are activated by CFA and calcium-rich nanoparticles and/or soluble salts within CFA. Human TRPM8 activation by CFA was potentiated by cold temperature and involved the phosphatidylinositol 4,5-bisphosphate binding site (L1008). Activation also occurred independent of the icilin and menthol binding site residue Y745, as well as to a large extent, the N-terminal amino acids 1-800. CFA, calcium nanoparticles and calcium salts also activated TRPV1 and TRPA1, but not TRPV4. Finally, CFA treatment caused CXCL1 and IL-8 mRNA induction in BEAS-2B and primary human bronchial epithelial cells through activation of both TRPM8 and TRPV1. However, neither mouse nor rat TRPM8 were activated by these materials, and Trpm8-knockout had no effect on cytokine induction in the lungs of mice following CFA instillation. These results imply that TRPM8, in conjunction with TRPV1 and TRPA1, might sense selected forms of inhaled particulate materials in human airways, shaping cellular responses to these materials. These findings improve our understanding of how and why certain particulate materials elicit different responses in biological systems, as well as ways in which certain particles might affect human health. The American Society for Pharmacology and Experimental Therapeutics.

  9. 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


    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

  10. Activation of transient receptor potential ankyrin-1 (TRPA1) in lung cells by wood smoke particulate material. (United States)

    Shapiro, Darien; Deering-Rice, Cassandra E; Romero, Erin G; Hughen, Ronald W; Light, Alan R; Veranth, John M; Reilly, Christopher A


    Cigarette smoke, diesel exhaust, and other combustion-derived particles activate the calcium channel transient receptor potential ankyrin-1 (TRPA1), causing irritation and inflammation in the respiratory tract. It was hypothesized that wood smoke particulate and select chemical constituents thereof would also activate TRPA1 in lung cells, potentially explaining the adverse effects of wood and other forms of biomass smoke on the respiratory system. TRPA1 activation was assessed using calcium imaging assays in TRPA1-overexpressing HEK-293 cells, mouse primary trigeminal neurons, and human adenocarcinoma (A549) lung cells. Particles from pine and mesquite smoke were less potent agonists of TRPA1 than an equivalent mass concentration of an ethanol extract of diesel exhaust particles; pine particles were comparable in potency to cigarette smoke condensate, and mesquite particles were the least potent. The fine particulate (PM smoke were the most potent TRPA1 agonists and several chemical constituents of wood smoke particulate, 3,5-ditert-butylphenol, coniferaldehyde, formaldehyde, perinaphthenone, agathic acid, and isocupressic acid, were TRPA1 agonists. Pine particulate activated TRPA1 in mouse trigeminal neurons and A549 cells in a concentration-dependent manner, which was inhibited by the TRPA1 antagonist HC-030031. TRPA1 activation by wood smoke particles occurred through the electrophile/oxidant-sensing domain (i.e., C621/C641/C665/K710), based on the inhibition of cellular responses when the particles were pretreated with glutathione; a role for the menthol-binding site of TRPA1 (S873/T874) was demonstrated for 3,5-ditert-butylphenol. This study demonstrated that TRPA1 is a molecular sensor for wood smoke particulate and several chemical constituents thereof, in sensory neurons and A549 cells, suggesting that TRPA1 may mediate some of the adverse effects of wood smoke in humans.

  11. Relative humidity-dependent viscosity of secondary organic material from toluene photo-oxidation and possible implications for organic particulate matter over megacities

    Energy Technology Data Exchange (ETDEWEB)

    Song, Mijung; Liu, Pengfei F.; Hanna, Sarah J.; Zaveri, Rahul A.; Potter, Katie; You, Yuan; Martin, Scot T.; Bertram, Allan K.


    To improve predictions of air quality, visibility, and climate change, knowledge of the viscosities and diffusion rates within organic particulate matter consisting of secondary organic material (SOM) is required. Most qualitative and quantitative measurements of viscosity and diffusion rates within organic particulate matter have focused on SOM particles generated from biogenic volatile organic compounds (VOCs) such as α-pinene and isoprene. In this study, we quantify the relative humidity (RH)-dependent viscosities at 295±1K of SOM produced by photo-oxidation of toluene, an anthropogenic VOC. The viscosities of toluene-derived SOM were 2 × 10₋1 to ~6 ×106Pa s from 30 to 90%RH, and greater than ~2 × 108 Pa s (similar to or greater than the viscosity of tar pitch) for RH ≤ 17%. These viscosities correspond to Stokes–Einstein-equivalent diffusion coefficients for large organic molecules of ~2 ×10₋15cm2s₋1 for 30 % RH, and lower than ~3 × 10₋17cm2s₋1 for RH ≤ 17 %. Based on these estimated diffusion coefficients, the mixing time of large organic molecules within 200 nm toluene-derived SOM particles is 0.1–5 h for 30% RH, and higher than ~100 h for RH ≤ 17%. As a starting point for understanding the mixing times of large organic molecules in organic particulate matter over cities, we applied the mixing times determined for toluene-derived SOM particles to the world's top 15 most populous megacities. If the organic particulate matter in these megacities is similar to the toluene-derived SOM in this study, in Istanbul, Tokyo, Shanghai, and São Paulo, mixing times in organic particulate matter during certain periods of the year may be very short, and the particles may be well-mixed. On the other hand, the mixing times of large organic molecules in organic particulate matter in Beijing, Mexico City, Cairo, and Karachi may be long

  12. Characterization of atmospheric particulate and metallic elements at Taichung Harbor near Taiwan Strait during 2004-2005. (United States)

    Fang, Guor-Cheng; Wu, Yuh-Shen; Lin, Jum-Bo; Lin, Chi-Kwong; Rau, Jui-Yeh; Huang, Shih-Han


    Air aerosol samples for TSP (total suspended particulate), coarse particulate (particle matter with aerodynamical diameter 2.5-10 microm, PM(2.5-10)), fine particulate (particle matter with aerodynamical diameter metallic elements were collected during March 2004 to January 2005 at TH (Taichung Harbor) in central Taiwan. The seasonal variation average concentration of TSP (total suspended particulate), coarse particulate (particle matter with aerodynamical diameter 2.5-10 microm, PM(2.5-10)) and fine particulate (particle matter with aerodynamical diameter metallic elements Cu, Mn, Zn and Fe in the TSP (total suspended particulate) shows that higher concentration was observed during spring. Seasonal variation of metallic elements Pb, Cr and Mg in the TSP (total suspended particulate) shows that higher concentration was observed during winter. The average metallic element TSP (total suspended particulate) concentration order was Fe>Zn>Mg>Cu>Cr>Mn>Pb in spring. In addition, at the TH sampling site, the average concentration variation of TSP (total suspended particulate) displayed the following order: spring>winter>autumn>summer. However, the average concentration variation of coarse particulate (particle matter with aerodynamical diameter 2.5-10 microm, PM(2.5-10)) displayed the following order: spring>winter>summer>autumn. Finally, the average concentration variations of fine particulate (particle matter with aerodynamical diameter spring>summer>autumn at the TH sample site.

  13. 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...

  14. Laboratory evaluation of airborne particulate control treatments for simulated aircraft crash recovery operations involving carbon fiber composite materials. (United States)

    Ferreri, Matthew; Slagley, Jeremy; Felker, Daniel


    This study compared four treatment protocols to reduce airborne composite fiber particulates during simulated aircraft crash recovery operations. Four different treatments were applied to determine effectiveness in reducing airborne composite fiber particulates as compared to a "no treatment" protocol. Both "gold standard" gravimetric methods and real-time instruments were used to describe mass per volume concentration, particle size distribution, and surface area. The treatment protocols were applying water, wetted water, wax, or aqueous film-forming foam (AFFF) to both burnt and intact tickets of aircraft composite skin panels. The tickets were then cut using a small high-speed rotary tool to simulate crash recovery operations. Aerosol test chamber. None. Airborne particulate control treatments. Measures included concentration units of milligrams per cubic meter of air, particle size distribution as described by both count median diameter and mass median diameter and geometric standard deviation of particles in micrometers, and surface area concentration in units of square micrometers per cubic centimeter. Finally, a Monte Carlo simulation was run on the particle size distribution results. Comparison was made via one-way analysis of variance. A significant difference (pcrash recovery operations should include a treatment of the debris with water or wetted water. The resulting increase in particle size will make respiratory protection more effective in protecting the response crews.

  15. Influence of suspended kelp culture on seabed sediment composition in Heini Bay, China (United States)

    Liu, Yanxia; Huang, Haijun; Yan, Liwen; Liu, Xiao; Zhang, Zehua


    Kelp aquaculture activities occupy large nearshore areas with significant effects on sediment properties, primarily caused by the influence of the suspended kelp on local hydrodynamics. Changes in sediment composition and grain-size distributions were investigated prior to and following the commencement of kelp aquaculture activities in Heini Bay in eastern China. Seabed sediment types and the particulate matter in suspension during the kelp seeding and harvesting periods, and in sediment cores, were analyzed. While suspended sediment in the kelp aquaculture area was up to 20% organic material, sediment organic content on the seabed remained at similar levels as areas lacking aquaculture. The composition of the seabed sediment in the kelp aquaculture area became finer-grained by the capture of fine particles. Within the kelp aquaculture area, the sediments are poorly sorted and positively skewed, whereas at the shoreward and seaward of the aquaculture area the sediments are relatively coarse-grained, well-sorted and nearly symmetrically distributed. Therefore, the kelp aquaculture activities not only increase the fine particulate fraction in the sediments within the aquaculture area, but also result in similar deposits seaward of it, indicating that seabed erosion and accretion is also controlled by the sediment source and the hydrodynamic conditions. The analysis of sediment cores showed that kelp culturing refines the sediment by preferentially capturing particles in the 38-40 μm size class, while having no effect on the kelp aquaculture area. The same effect was observed in the seabed sediments seaward of the aquaculture area.

  16. Magneto-optical Faraday effect in suspended core micro-structured optical fiber filled with magnetic CoFe2O4 nanoparticles doped composite material (United States)

    Jamon, D.; Marin, E.; Neveu, S.; Blanc-Mignon, M.-F.; Royer, F.


    This paper deals with the study of the magneto-optical Faraday effect of micro-structured optical fibers with suspended cores covered by a silica matrix doped by CoFe2O4 nanoparticles. Two different size distributions of nanoparticles originated from two magnetic fluids have been used to dope a sol-gel preparation later introduced in the fiber. Faraday rotation measurements were performed in liquid state, thin film and finally in the fiber in guided configuration. The two different magnetic behaviors of these nanoparticles collections allow us to evidence the Faraday effect of the micro-structured optical fiber.

  17. The interaction of human microbial pathogens, particulate material and nutrients in estuarine environments and their impacts on recreational and shellfish waters. (United States)

    Malham, Shelagh K; Rajko-Nenow, Paulina; Howlett, Eleanor; Tuson, Karen E; Perkins, Tracy L; Pallett, Denise W; Wang, Hui; Jago, Colin F; Jones, Davey L; McDonald, James E


    Anthropogenic activities have increased the load of faecal bacteria, pathogenic viruses and nutrients in rivers, estuaries and coastal areas through point and diffuse sources such as sewage discharges and agricultural runoff. These areas are used by humans for both commercial and recreational activities and are therefore protected by a range of European Directives. If water quality declines in these zones, significant economic losses can occur. Identifying the sources of pollution, however, is notoriously difficult due to the ephemeral nature of discharges, their diffuse source, and uncertainties associated with transport and transformation of the pollutants through the freshwater-marine interface. Further, significant interaction between nutrients, microorganisms and particulates can occur in the water column making prediction of the fate and potential infectivity of human pathogenic organisms difficult to ascertain. This interaction is most prevalent in estuarine environments due to the formation of flocs (suspended sediment) at the marine-freshwater interface. A range of physical, chemical and biological processes can induce the co-flocculation of microorganisms, organic matter and mineral particles resulting in pathogenic organisms becoming potentially protected from a range of biotic (e.g. predation) and abiotic stresses (e.g. UV, salinity). These flocs contain and retain macro- and micro- nutrients allowing the potential survival, growth and transfer of pathogenic organisms to commercially sensitive areas (e.g. beaches, shellfish harvesting waters). The flocs can either be transported directly to the coastal environment or can become deposited in the estuary forming cohesive sediments where pathogens can survive for long periods. Especially in response to storms, these sediments can be subsequently remobilised releasing pulses of potential pathogenic organisms back into the water column leading to contamination of marine waters long after the initial

  18. The detection of iron protoporphyrin (heme b) in phytoplankton and marine particulate material by electrospray ionisation mass spectrometry – comparison with diode array detection

    Energy Technology Data Exchange (ETDEWEB)

    Gledhill, Martha, E-mail:


    Highlights: • Mass spectrometry was applied to the analysis of heme b in biological material. • Optimal conditions involved selective reactant monitoring of the heme b product ion. • The isotopic signature for this iron tetrapyrrole further improved selectivity. • Mass spectrometry and spectrophotometry were compared for heme b analysis. • Combining techniques made a powerful tool for analysis of heme in marine microbes. - Abstract: A mass spectrometric (MS) method for the identification of iron protoporphyrin (IX) (FePTP, heme b) in marine particulate material and phytoplankton is described. Electrospray ionisation of FePTP produced the molecular Fe(III)PTP{sup +} ion (m/z = 616) or the pseudomolecular [Fe(II)PTP + H]{sup +} ion (m/z = 617), depending on the oxidation state of the central iron ion. Collision induced dissociation (CID) in the ion trap mass spectrometer resulted in a single detected product ion (m/z = 557) indicative of loss of ethanoic acid from a carboxylic acid side chain. Widening the isolation width to 616 ± 3 resulted in production of a mass spectrum demonstrating the distinctive isotopic ratio of the iron containing fragment, further increasing the specificity of the analysis. Selective reactant monitoring (SRM) of the fragment ion (m/z = 557) was applied to the detection of FePTP after chromatography of ammoniacal OGP extracts of marine samples. The detection limit for FePTP analysed by SRM after chromatography was 1.2 ± 0.5 fmol. For phytoplankton samples, reasonably good agreement was achieved between results obtained with SRM and those obtained by monitoring absorbance at λ = 400 nm using a diode array detector (DAD). Use of SRM for analysis of particulate material obtained from the high latitude North Atlantic allowed for the analysis of FePTP in the presence of a co-eluting compound that interfered with detection by DAD. Simultaneous collection of mass spectra from m/z = 300 to 1500 resulted in identification of the

  19. 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...

  20. The detection of iron protoporphyrin (heme b) in phytoplankton and marine particulate material by electrospray ionisation mass spectrometry - comparison with diode array detection. (United States)

    Gledhill, Martha


    A mass spectrometric (MS) method for the identification of iron protoporphyrin (IX) (FePTP, heme b) in marine particulate material and phytoplankton is described. Electrospray ionisation of FePTP produced the molecular Fe(III)PTP(+) ion (m/z=616) or the pseudomolecular [Fe(II)PTP + H](+) ion (m/z=617), depending on the oxidation state of the central iron ion. Collision induced dissociation (CID) in the ion trap mass spectrometer resulted in a single detected product ion (m/z=557) indicative of loss of ethanoic acid from a carboxylic acid side chain. Widening the isolation width to 616±3 resulted in production of a mass spectrum demonstrating the distinctive isotopic ratio of the iron containing fragment, further increasing the specificity of the analysis. Selective reactant monitoring (SRM) of the fragment ion (m/z=557) was applied to the detection of FePTP after chromatography of ammoniacal OGP extracts of marine samples. The detection limit for FePTP analysed by SRM after chromatography was 1.2±0.5fmol. For phytoplankton samples, reasonably good agreement was achieved between results obtained with SRM and those obtained by monitoring absorbance at λ=400nm using a diode array detector (DAD). Use of SRM for analysis of particulate material obtained from the high latitude North Atlantic allowed for the analysis of FePTP in the presence of a co-eluting compound that interfered with detection by DAD. Simultaneous collection of mass spectra from m/z=300 to 1500 resulted in identification of the pseudomolecular ion for the interfering compound. The CID fragmentation pattern and UV-visible mass spectra indicated that the interfering compound was a previously unidentified chlorin type compound. Comparison of FePTP determined by SRM and DAD on samples where this compound could not be detected showed that results collected using the two methods correlated. The use of both MS and DAD results in a powerful tool for quantifying this important biogenic component of the


    African Journals Online (AJOL)

    DR. AMIN

    elements were observed in Motor Spray Painting (MSP),8528±389 g/m3 and Welding and Panel- beating (WDP) workshops, 11086.8±10644 g/m3. The calculated enrichment factor revealed Cd to be highly enriched in Battery Maintenance and Charging (BMC) and MSP. The enrichment factor of all the elements suggests ...

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

    Indian Academy of Sciences (India)

    cycle (McCarthy et al 1997). The distribution and cycling of AS in sedimenting particles and marine sediments have been well documented (Belluomini et al 1986; Haake et al 1992; Jennerjahn and. Ittekkot 1997; Hashimoto et al 1998; Gupta and. Kawahata 2000). Conversely, little is known about the distribution of AS in the ...

  3. Characterization of particulate material dynamics and composition in the benthic layer of the East Siberian Sea and adjacent part of the Laptev Sea: Fine vertical structure. (United States)

    Dudarev, Oleg; Charkin, Alexander; Semiletov, Igor; Gustafsson, Örjan; Vonk, Jorien; Sánchez-García, Laura


    The near-shore zone of the Laptev and East Siberian seas is the most climatically sensitive area in the Arctic and has the highest rates of coastal retreat (Grigoriev, EGU-2010, this session). Our multi-year data (1999-2009) show that major transport of terrestrial organic material to the East Siberian Arctic marine system results from coastal erosion. Biodegradation of this coastal material is a regional source of high pCO2 in waters of the East Siberian Arctic Shelf (ESAS) (Anderson et al., 2009; Pipko et al., EGU-2010, this session; Semiletov et al., 2007). Partitioning between eroded particulate organic carbon (POC) degradation in water and in sediment is still poorly studied. Here we present and discuss peculiarities of particulate material (PM) and POC distribution in the ESAS benthic layer obtained during the 50-day International Siberian Shelf Study (ISSS-2008) onboard the H/V Yakob Smirnitsky. Basic materials were obtained using a GEMAX corer, which allows the sampling of undisturbed surface sediments (down to 1 m in depth) and bottom water. It was found that the vertical PM gradient in the thin benthic layer was 3000 times larger than the PM gradient across the pycnocline. The highest gradients were found in the river paleocanyons and along the Chaunsky -Kolymski Trench. Vertical profiles of POC and its C13 and C/N ratio in the benthic layer demonstrate the increasing contribution of terrestrial organic carbon with increasing depth. References Anderson L.G., Jutterstro¨m S., S. Hjalmarsson S., I. Wahlstro¨m I., and I. P. Semiletov, 2009. Out-gassing of CO2 from Siberian Shelf seas by terrestrial organic matter decomposition. Geophysical Research Letters, 36, L20601, doi:10.1029/2009GL040046, 2009 Semiletov, I., I.I. Pipko, I.A. Repina, and N. Shakhova, 2007, Carbonate dynamics and carbon dioxide fluxes across the atmosphere-ice-water interfaces in the Arctic Ocean Pacific sector of the Arctic, Journal of Marine Systems, 66 (1-4), 204-226.

  4. 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)


    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.

  5. Cable suspended windmill (United States)

    Farmer, Moses G. (Inventor)


    A windmill is disclosed which includes an airframe having an upwind end and a downwind end. The first rotor is rotatably connected to the airframe, and a generator is supported by the airframe and driven by the rotor. The airframe is supported vertically in an elevated disposition by poles which extend vertically upwardly from the ground and support cables which extend between the vertical poles. Suspension cables suspend the airframe from the support cable.

  6. Grab vs. composite sampling of particulate materials with significant spatial heterogeneity--a simulation study of "correct sampling errors". (United States)

    Minkkinen, Pentti O; Esbensen, Kim H


    Sampling errors can be divided into two classes, incorrect sampling and correct sampling errors. Incorrect sampling errors arise from incorrectly designed sampling equipment or procedures. Correct sampling errors are due to the heterogeneity of the material in sampling targets. Excluding the incorrect sampling errors, which can all be eliminated in practice although informed and diligent work is often needed, five factors dominate sampling variance: two factors related to material heterogeneity (analyte concentration; distributional heterogeneity) and three factors related to the sampling process itself (sample type, sample size, sampling modus). Due to highly significant interactions, a comprehensive appreciation of their combined effects is far from trivial and has in fact never been illustrated in detail. Heterogeneous materials can be well characterized by the two first factors, while all essential sampling process characteristics can be summarized by combinations of the latter three. We here present simulations based on an experimental design that varies all five factors. Within the framework of the Theory of Sampling, the empirical Total Sampling Error is a function of the fundamental sampling error and the grouping and segregation error interacting with a specific sampling process. We here illustrate absolute and relative sampling variance levels resulting from a wide array of simulated repeated samplings and express the effects by pertinent lot mean estimates and associated Root Mean Squared Errors/sampling variances, covering specific combinations of materials' heterogeneity and typical sampling procedures as used in current science, technology and industry. Factors, levels and interactions are varied within limits selected to match realistic materials and sampling situations that mimic, e.g., sampling for genetically modified organisms; sampling of geological drill cores; sampling during off-loading 3-dimensional lots (shiploads, railroad cars, truckloads

  7. Measurement of fine particulate matter nonvolatile and semi-volatile organic material with the Sunset Laboratory Carbon Aerosol Monitor. (United States)

    Grover, Brett D; Kleinman, Michael; Eatough, Norman L; Eatough, Delbert J; Cary, Robert A; Hopke, Philip K; Wilson, William E


    Semi-volatile organic material (SVOM) in fine particles is not reliably measured with conventional semicontinuous carbon monitors because SVOM is lost from the collection media during sample collection. We have modified a Sunset Laboratory Carbon Aerosol Monitor to allow for the determination of SVOM. In a conventional Sunset monitor, gas-phase organic compounds are removed in the sampled airstream by a diffusion denuder employing charcoal-impregnated cellulose filter (CIF) surfaces. Subsequently, particles are collected on a quartz filter and the instrument then determines both the organic carbon and elemental carbon fractions of the aerosol using a thermal/optical method. However, some of the SVOM is lost from the filter during collection, and therefore is not determined. Because the interfering gas-phase organic compounds are removed before aerosol collection, the SVOM can be determined by filtering the particles at the instrument inlet and then replacing the quartz filter in the monitor with a charcoal-impregnated glass fiber filter (CIG), which retains the SVOM lost from particles collected on the inlet filter. The resulting collected SVOM is then determined in the analysis step by measurement of the carbonaceous material thermally evolved from the CIG filter. This concept was tested during field studies in February 2003 in Lindon, UT, and in July 2003 in Rubidoux, CA. The results obtained were validated by comparison with Particle Concentrator-Brigham Young University Organic Sampling System (PC-BOSS) results. The sum of nonvolatile organic material determined with a conventional Sunset monitor and SVOM determined with the modified Sunset monitor agree with the PC-BOSS results. Linear regression analysis of total carbon concentrations determined by the PC-BOSS and the Sunset resulted in a zero-intercept slope of 0.99 +/- 0.02 (R2 = 0.92) and a precision of sigma = +/- 1.5 microg C/m3 (8%).

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

    Indian Academy of Sciences (India)

    ; particulate carbohydrates; particulate uronic acids; organic matter, Bay of Bengal. ... Council of Scientific and Industrial Research, Marine Corrosion and Material Research Division, National Institute of Oceanography, Dona Paula 403 004, ...

  9. Spatial-Time Variability of Particulate Material Content and its Composition on the East Siberian Shelf: from Mesoscale to Interannual Variability (United States)

    Dudarev, O.; Charkin, A.; Shakhova, N. E.; Semiletov, I. P.; Gustafsson, O. M.; Vonk, J.; Sanchez-Garcia, L.


    Here we present the data obtained in the Russia-US cruises (FEBRAS, NOAA, NSF, and Russian Foundation for Basic Research, RFBR, funded) in 2000, 2003-2005, and in the International Siberian Shelf Study-2008 (ISSS-2008, supported by the Wallenberg Foundation, FEBRAS, NOAA, and RFBR) which characterized a spatial and inter-annual variability in distribution of particulate material (PM), and its organic carbon and stable isotopes content. The role of the coastal zone in lateral transport and fate of terrestrial organic carbon in the East Siberian Arctic Shelf (ESAS) is still not studied well because most recent activities were focused on onshore geomorphologic and geochemical features, while biogeochemical and sedimentation consequences of coastal erosion and riverine runoff in the sea were not studied sufficiently. Dynamics of PM and its composition was studied twice along the Lena river in summer-fall of 2003. Spatial-time dynamics of PM composition (POC and isotopes) along with its mineralogical composition is considered in connection with changing river runoff and wind patterns. It has been found that not the rivers (Lena, Yana, Indigirka, Kolyma), but the coastal erosion is a dominant source of terrestrial particulate organic carbon (POC) into the ESAS. That supports the hypothesis about the dominant role of coastal erosion in the offshore transport of terrestrial organic carbon and sedimentation in the ESAS proposed by Semiletov (DAN, 1999). The PM concentration sharp gradient was found across the frontal zone between 'freshened/high PM' and 'Pacific/low PM' waters. Position of the frontal zone varies significantly from year to year. It is mainly attributed to the difference in atmospheric circulation patterns driven the Arctic Ocean circulation. During storms and surges the PM concentration in the same area increased up to 10-times and higher (up to 80-242 mg/l) in 2000 and 2005 comparing the 2003 and 2004. Values of total PM and other environmental parameters

  10. Comparison of speciation sampler and PC-BOSS fine particulate matter organic material results obtained in Lindon, Utah, during winter 2001-2002. (United States)

    Carter, Cory; Eatough, Norman L; Eatough, Delbert J; Olson, Neal; Long, Russell W


    The Particle Concentrator-Brigham Young University Organic Sampling System (PC-BOSS) has been previously verified as being capable of measuring total fine particulate matter (PM2.5), including semi-volatile species. The present study was conducted to determine if the simple modification of a commercial speciation sampler with a charcoal denuder followed by a filter pack containing a quartz filter and a charcoal-impregnated glass (CIG) fiber filter would allow for the measurement of total PM2.5, including semi-volatile organic material. Data were collected using an R&P (Rupprecht and Pastasnik Co., Inc.) Partisol Model 2300 speciation sampler; an R&P Partisol speciation sampler modified with a BOSS denuder, followed by a filter pack with a quartz and a CIG filter; a Met One spiral aerosol speciation sampler (SASS); and the PC-BOSS from November 2001 to March 2002 at a U.S. Environmental Protection Agency (EPA) Science to Achieve Results (STAR) sampling site in Lindon, UT. Total PM2.5 mass, ammonium nitrate (both nonvolatile and semi-volatile), ammonium sulfate, organic carbon (both non-volatile and semi-volatile), and elemental carbon were determined on a 24-hr basis. Results obtained with the individual samplers were compared to determine the capability of the modified R&P speciation sampler for measuring total PM2.5, including semi-volatile components. Data obtained with the modified speciation sampler agreed with the PC-BOSS results. Data obtained with the two unmodified speciation samplers were low by an average of 26% because of the loss of semi-volatile organic material from the quartz filter during sample collection.

  11. Dispersive suspended microextraction. (United States)

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


    A novel sample pre-treatment technique termed dispersive suspended microextraction (DSME) coupled with gas chromatography-flame photometric detection (GC-FPD) has been developed for the determination of eight organophosphorus pesticides (ethoprophos, malathion, chlorpyrifos, isocarbophos, methidathion, fenamiphos, profenofos, triazophos) in aqueous samples. In this method, both extraction and two phases' separation process were performed by the assistance of magnetic stirring. After separating the two phases, 1 μL of the suspended phase was injected into GC for further instrument analysis. Varieties of experiment factors which could affect the experiment results were optimized and the following were selected: 12.0 μL p-xylene was selected as extraction solvent, extraction speed was 1200 rpm, extraction time was 30 s, the restoration speed was 800 rpm, the restoration time was 8 min, and no salt was added. Under the optimum conditions, limits of detections (LODs) varied between 0.01 and 0.05 μg L(-1). The relative standard deviation (RSDs, n=6) ranged from 4.6% to 12.1%. The linearity was obtained by five points in the concentration range of 0.1-100.0 μg L(-1). Correlation coefficients (r) varied from 0.9964 to 0.9995. The enrichment factors (EFs) were between 206 and 243. In the final experiment, the developed method has been successfully applied to the determination of organophosphorus pesticides in wine and tap water samples and the obtained recoveries were between 83.8% and 101.3%. Compared with other pre-treatment methods, DSME has its own features and could achieve satisfied results for the analysis of trace components in complicated matrices. Copyright © 2011 Elsevier B.V. All rights reserved.

  12. Distribution and origin of suspended matter and organic carbon pools in the Tana River Basin, Kenya

    Directory of Open Access Journals (Sweden)

    F. Tamooh


    Full Text Available We studied patterns in organic carbon pools and their origin in the Tana River Basin (Kenya, in February 2008 (dry season, September–November 2009 (wet season, and June–July 2010 (end of wet season, covering the full continuum from headwater streams to lowland mainstream sites. A consistent downstream increase in total suspended matter (TSM, 0.6 to 7058 mg l−1 and particulate organic carbon (POC, 0.23 to 119.8 mg l−1 was observed during all three sampling campaigns, particularly pronounced below 1000 m above sea level, indicating that most particulate matter exported towards the coastal zone originated from the mid and low altitude zones rather than from headwater regions. This indicates that the cascade of hydroelectrical reservoirs act as an extremely efficient particle trap. Although 7Be / 210Pbxs ratios/age of suspended sediment do not show clear seasonal variation, the gradual downstream increase of suspended matter during end of wet season suggests its origin is caused by inputs of older sediments from bank erosion and/or river sediment resuspension. During wet season, higher TSM concentrations correspond with relatively young suspended matter, suggesting a contribution from recently eroded material. With the exception of reservoir waters, POC was predominantly of terrestrial origin as indicated by generally high POC : chlorophyll a (POC : Chl a ratios (up to ~41 000. Stable isotope signatures of POC (δ13CPOC ranged between −32 and −20‰ and increased downstream, reflecting an increasing contribution of C4-derived carbon in combination with an expected shift in δ13C for C3 vegetation towards the more semi-arid lowlands. δ13C values in sediments from the main reservoir (−19.5 to −15.7‰ were higher than those found in any of the riverine samples, indicating selective retention of particles associated with C4

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

    Directory of Open Access Journals (Sweden)

    T.F. Ediagbonya


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

  14. Influence of wound closure on the volume stability of particulate and non-particulate GBR materials: an in vitro cone-beam computed tomographic examination. Part II. (United States)

    Mir-Mari, Javier; Benic, Goran I; Valmaseda-Castellón, Eduard; Hämmerle, Christoph H F; Jung, Ronald E


    To test whether GBR with an L-shaped soft-block bone substitute and particulate bone substitute differs from GBR with particulate bone substitute as regards the volume stability of the augmented region during flap closure. Twenty peri-implant box-shaped bone defects were created in 10 pig mandibles. Every bone defect was augmented with each of the following two GBR procedures in turn: control group - particulate xenograft applied buccally + collagen membrane + pins; test group - particulate xenograft applied buccally + L-shaped soft-block xenograft applied buccally and occlusally + collagen membrane + pins. Cone-beam computed tomography scans were obtained before and after wound closure. The horizontal thickness (HT) of the augmented region (bone substitute + membrane) was assessed at the implant shoulder (HT 0 mm ) and at 1 mm to 5 mm apical to the implant shoulder (HT 1 mm -HT 5 mm ). In the test group, the vertical thickness (VT) and 45° thickness (45-T) of the augmented region were measured from the implant shoulder. The changes in HT during flap suturing were calculated as absolute (mm) and relative values (%). Repeated-measures ANOVAs were used for statistical analysis. The reduction in HT 0 mm was 20.5 ± 23.3% (SD) in the control group and 2.4 ± 9.2% (SD) in the test group (P = 0.014). There were no statistically significant differences in changes in HT 1-5 mm between the groups (P > 0.05). In the test group, the reduction in VT amounted to 28.0 ± 11.9% (SD) and the reduction in 45-T amounted to 24.8 ± 10.2% (SD) (P membrane and fixed with pins, significantly improved the horizontal volume stability of the augmented region during wound closure. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  15. Preliminary analysis of variability in concentration of fine particulate matter - PM1.0, PM2.5 and PM10 in area of Poznań city (United States)

    Sówka, Izabela; Chlebowska-Styś, Anna; Mathews, Barbara


    It is commonly known, that suspended particulate matter pose a threat to human life and health, negatively influence the flora, climate and also materials. Especially dangerous is the presence of high concentration of particulate matter in the area of cities, where density of population is high. The research aimed at determining the variability of suspended particulate matter concentration (PM1.0, PM2.5 and PM10) in two different thermal seasons, in the area of Poznań city. As a part of carried out work we analyzed the variability of concentrations and also performed a preliminary analysis of their correlation. Measured concentrations of particulate matter were contained within following ranges: PM10 - 8.7-69.6 μg/m3, PM2.5 - 2.2-88.5 μg/m3, PM1.0 - 2.5-22.9 μg/m3 in the winter season and 1.0-42.8 μg/m3 (PM10), 1.2-40.3 μg/m3 (PM2.5) and 2.7-10.4 (PM1.0) in the summer season. Preliminary correlative analysis indicated interdependence between the temperature of air, the speed of wind and concentration of particulate matter in selected measurement points. The values of correlation coefficients between the air temperature, speed of wind and concentrations of particulate matter were respectively equal to: for PM10: -0.59 and -0.55 (Jana Pawła II Street), -0.53 and -0.53 (Szymanowskiego Street), for PM2.5: -0.60 and -0.53 (Jana Pawła II Street) and for PM1.0 -0.40 and -0.59 (Jana Pawła II Street).

  16. Report of meeting on measurement of suspended solids in the Meuse

    NARCIS (Netherlands)

    Joziasse, J.; Klaver, G.; Bakker, I.


    On June 19/20, 2007 a visit was paid to a suspended particulate matter (SPM) sampling and monitoring site in the Ourthe river (Liège region), between the confluence with the Vesdre river and the mouth of the Ourthe in the Meuse river. The next day, a workshop was organised in which backgrounds,

  17. 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...

  18. Temporal and Spatial Scales of Terrestrially-derived Particulate and Dissolved Materials in the Penobscot River System: Quantifying Conserved and Nonconserved Optical Properties and Transformations within the Estuary (United States)


    drainage of freshwater wetlands and high CDOM concentrations in the tributaries; (2) fluorometric chlorophyll significantly underestimate extracted...phytoplankton particulate organic N and P (rather than the inorganic dissolved NO3 and PO4 ); Figure 2. Phytoplankton in Penobscot River. A...proxy for DOC, particularly for stations that are not characterized by freshwater wetlands (Figure 4A). These wetland stations exhibit a lower

  19. Particulate Matter (PM) Pollution (United States)

    ... Environmental Protection Agency Search Search Particulate Matter (PM) Pollution Contact Us Share Most PM particles form in ... and cause serious health effects. Particulate Matter (PM) Pollution PM Basics What is PM, and how does ...

  20. The suspended sentence in French Criminal Law

    Directory of Open Access Journals (Sweden)

    Jovašević Dragan


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

  1. Composición química y reconstrucción másica del material particulado suspendido en el aire de Bogotá Chemical composition and mass closure for airborne particulate matter in Bogotá

    Directory of Open Access Journals (Sweden)

    Rojas Néstor Y.


    Full Text Available El material particulado, medido como PM10, es el contaminante que más afecta la calidad del aire en Bogotá. Conocer la composición del material particulado es crucial para en- tender cuáles son las fracciones químicas que más aportan a ese contaminante e identificar posibles fuentes generadoras de él. En este artículo se presenta el resultado de la caracterización de especies iónicas, fracciones carbonáceas, meta- les y elementos minerales del material particulado en dos puntos de Bogotá. Con base en los resultados de caracterización se realiza un análisis de neutralidad iónica y reconstrucción másica para comparar la consistencia de los resulta- dos obtenidos. La composición es diferente para cada sector, pero en general las fracciones que más aportan al material particulado son la geológica (asociada a polvo fugitivo y re- suspendido, entre el 37 y 42%; las fracciones carbonáceas, que son las que más aportan, entre un 12 y 11% para el car- bono elemental y un 43 y 34% para materia orgánica; la fracción iónica se encontró entre un 5 y 8%.Particulate matter, measured as PM10, is the most concerning airborne pollutant in Bogotá. Determining its chemical com- position is important for understanding its potential effects and to estimate various sources’ contribution to such pollution. This paper gives the results of characterizing the ionic species, carbonaceous material, metals and crustal elements present in airborne PM10 in Bogotá. An ion charge balance and mass reconstruction were done for determining consistency between chemical characterization and gravimetric PM10. The composition was different in each area; however, the fractions contributing most to PM10 were crustal, 37% to 42% was related to fugitive and suspended dust, 12% to 11% was related to carbonaceus fractions, 43% to elemental carbon, 34% for organic matter and 5% to 8% for ionic fractions.


    Energy Technology Data Exchange (ETDEWEB)

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


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

  3. Electrically heated particulate filter enhanced ignition strategy (United States)

    Gonze, Eugene V; Paratore, Jr., Michael J


    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.

  4. Coated electroactive materials

    Energy Technology Data Exchange (ETDEWEB)

    Amine, Khalil; Abouimrane, Ali


    A process includes suspending an electroactive material in a solvent, suspending or dissolving a carbon precursor in the solvent; and depositing the carbon precursor on the electroactive material to form a carbon-coated electroactive material. Compositions include a graphene-coated electroactive material prepared from a solution phase mixture or suspension of an electroactive material and graphene, graphene oxide, or a mixture thereof.

  5. Simulation of suspended sediment transport initialized with satellite derived suspended sediment concentrations (United States)

    Ramakrishnan, Ratheesh; Rajawat, A. S.


    Suspended sediment transport in the Gulf of Kachchh is simulated utilizing the suspended sediment concentration (SSC) derived from Oceansat OCM imagery, as the initial condition in MIKE-21 Mud Transport model. Optimization of the model mud parameters, like settling velocity and critical shear stress for erosion are realized with respect to the sediment size distribution and the bottom bed materials observed in the Gulf. Simulated SSCs are compared with alternate OCM derived SSC. The results are observed to be impetus where the model is able to generate the spatial dynamics of the sediment concentrations. Sediment dynamics like deposition, erosion and dispersion are explained with the simulated tidal currents and OCM derived sediment concentrations. Tidal range is observed as the important physical factor controlling the deposition and resuspension of sediments within the Gulf. From the simulation studies; maximum residual current velocities, tidal fronts and high turbulent zones are found to characterise the islands and shoals within the Gulf, which results in high sediment concentrations in those regions. Remarkable variability in the bathymetry of the Gulf, different bed materials and varying tidal conditions induces several circulation patterns and turbulence creating the unique suspended sediment concentration pattern in the Gulf.

  6. Geospatial approach towards enumerative analysis of suspended sediment concentration for Ganges-Brahmaputra Bay (United States)

    Pandey, Palak; Kunte, Pravin D.


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

  7. Chemical composition and mass closure for airborne particulate matter in Bogotá

    Directory of Open Access Journals (Sweden)

    Freddy A. Vargas


    Full Text Available Particulate matter, measured as PM10, is the most concerning airborne pollutant in Bogotá. Determining its chemical com- position is important for understanding its potential effects and to estimate various sources’ contribution to such pollution. This paper gives the results of characterizing the ionic species, carbonaceous material, metals and crustal elements present in airborne PM10 in Bogotá. An ion charge balance and mass reconstruction were done for determining consistency between chemical characterization and gravimetric PM10. The composition was different in each area; however, the fractions contributing most to PM10 were crustal, 37% to 42% was related to fugitive and suspended dust, 12% to 11% was related to carbonaceus fractions, 43% to elemental carbon, 34% for organic matter and 5% to 8% for ionic fractions.

  8. Suspended animation for delayed resuscitation. (United States)

    Safar, Peter J; Tisherman, Samuel A


    'Suspended animation for delayed resuscitation' is a new concept for attempting resuscitation from cardiac arrest of patients who currently (totally or temporarily) cannot be resuscitated, such as traumatic exsanguination cardiac arrest. Suspended animation means preservation of the viability of brain and organism during cardiac arrest, until restoration of stable spontaneous circulation or prolonged artificial circulation is possible. Suspended animation for exsanguination cardiac arrest of trauma victims would have to be induced within the critical first 5 min after the start of cardiac arrest no-flow, to buy time for transport and resuscitative surgery (hemostasis) performed during no-flow. Cardiac arrest is then reversed with all-out resuscitation, usually requiring cardiopulmonary bypass. Suspended animation has been explored and documented as effective in dogs in terms of long-term survival without brain damage after very prolonged cardiac arrest. In the 1990s, the Pittsburgh group achieved survival without brain damage in dogs after cardiac arrest of up to 90 min no-flow at brain (tympanic) temperature of 10 degrees C, with functionally and histologically normal brains. These studies used emergency cardiopulmonary bypass with heat exchanger or a single hypothermic saline flush into the aorta, which proved superior to pharmacologic strategies. For the large number of normovolemic sudden cardiac death victims, which currently cannot be resuscitated, more research in large animals is needed.

  9. Elastic properties of suspended multilayer WSe2 (United States)

    Zhang, Rui; Koutsos, Vasileios; Cheung, Rebecca


    We report the experimental determination of the elastic properties of suspended multilayer WSe2, a promising two-dimensional (2D) semiconducting material combined with high optical quality. The suspended WSe2 membranes have been fabricated by mechanical exfoliation of bulk WSe2 and transfer of the exfoliated multilayer WSe2 flakes onto SiO2/Si substrates pre-patterned with hole arrays. Then, indentation experiments have been performed on these membranes with an atomic force microscope. The results show that the 2D elastic modulus of the multilayer WSe2 membranes increases linearly while the prestress decreases linearly as the number of layers increases. The interlayer interaction in WSe2 has been observed to be strong enough to prevent the interlayer sliding during the indentation experiments. The Young's modulus of multilayer WSe2 (167.3 ± 6.7 GPa) is statistically independent of the thickness of the membranes, whose value is about two thirds of other most investigated 2D semiconducting transition metal dichalcogenides, namely, MoS2 and WS2. Moreover, the multilayer WSe2 can endure ˜12.4 GPa stress and ˜7.3% strain without fracture or mechanical degradation. The 2D WSe2 can be an attractive semiconducting material for application in flexible optoelectronic devices and nano-electromechanical systems.

  10. Net transport of suspended matter due to tidal straining (United States)

    Jones, S. E.; Jago, C. F.; Simpson, J. H.; Rippeth, T. P.


    Net transport of suspended particulate matter (SPM) is well-known in tidal regions where there is time-velocity asymmetry due to frictional modification of the tide in shallow water. We present here observations which show a new mechanism for net flux of SPM in response to tidal straining in a region of freshwater influence (ROFI). In situ measurements of the particle size of suspended particulate matter (SPM) and turbulent energy dissipation have been made at a site in Liverpool Bay (Irish Sea) where there is significant resuspension of particles from the muddy sand substrate during spring tides. This is a ROFI where tidal straining dominates the temporal development of turbulence. On a spring tide the water column tries to stratify on the ebb and destratify on the flood, but these tendencies are masked by mixing due to tidal stirring. Nevertheless, there is a marked excess of TKE dissipation rate E on the flood, especially in the upper part of the water column. Resuspension occurs on both flood and ebb, but SPM flux is strongly asymmetric with a net shorewards component. Asymmetry is most pronounced for the larger particles which comprise most of the mass. Enhanced ? on the flood mixes large particles upwards into faster flowing water, which increases the flux. Comparable upwards mixing of large particles does not occur on the ebb where enhanced E is confined to slower bottom waters. The net flux is not seen on neap tides because, although there is more stratification due to tidal straining, there is essentially no resuspension. The net flux on springs is undoubtedly an important component of SPM transport (and any comparable particulates) in coastal regions.

  11. Instability and Turbulence of Propagating Particulate Flows (United States)

    Balachandar, S.


    Propagation of particle-laden fluid into an ambient is a common fluid mechanical process that can be observed in many industrial and environmental applications. Sedimentation fronts, volcanic plumes, dust storms, powder snow avalanches, submarine turbidity currents, explosive powder dispersal and supernovae offer fascinating examples of advancing particulate fronts. The propagating interface can undergo Rayleigh-Taylor, Kelvin-Helmholtz and double-diffusive instabilities and result in the formation of lobes and clefts, spikes and bubbles, and particulate fingers. The interplay between suspended particles and turbulence is often complex due to interaction of competing mechanisms. In problems such as turbidity currents, turbulence controls sediment concentration through resuspension and settling of particles at the bed. Also, turbulent entrainment at the propagating front is observed to be influenced by the sediments. Stable stratification due to suspended sediment concentration can damp and even kill turbulence. This complex turbulence-sediment interaction offers possible explanation for massive sediment deposits observed in nature. The talk will also address challenges and recent advancements in the modeling and simulation of such particle-laden turbulent flows.

  12. Remote Sensing Studies of Suspended Sediment Concentration Variation in Barito Delta (United States)

    Arisanty, Deasy; Nur Saputra, Aswin


    The dynamic of suspended sediment concentration in Barito Delta depend on the process in upstream. Agriculture, mining, and illegal logging in Barito River upstream has an effect for suspended sediment concentration in Barito Delta. The objective of research is to estimate the variation of suspended sediment concentration in Barito Delta. The data of research consist of Landsat 7 in year 2011 and measurement result data of suspended sediment concentration both in wet season and dry season in year 2011. Data analysis is regression analysis to estimates the variation of suspended sediment concentration in Barito Delta. The method of research compares three types of spectral transformation for suspended sediment that is Normalized Suspended Material Index (NSMI), Normalized Differences Suspended Sediment Index (NDSSI), and band ratio (green/blue). The result of the transformation is compared with the value of the field measurement. Based on the result of the comparison can be known the suitable type of transformation for the suspended sediment estimation in Barito Delta. The result of research explains that NSMI has the highest value to estimate the variation of suspended sediment concentration in Barito Delta.

  13. 7 CFR 1206.21 - Suspend. (United States)


    ... part thereof during a particular period of time specified in the rule. ... AND ORDERS; MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE MANGO PROMOTION, RESEARCH, AND INFORMATION Mango Promotion, Research, and Information Order Definitions § 1206.21 Suspend. Suspend means to...

  14. Stabilised suspending efficiency of Laponite XLG and sodium ...

    African Journals Online (AJOL)

    Charged drugs like Sulphamerazine may make pseudoplastic/plastic materials become Newtonian and loose their suspending power. In this study ... For this purpose, the rheograms of the systems were obtained by the use of a Haake rotoviscometer RV 12 utilizing a cup and rotor sensor system MV 1. In the absence of ...

  15. Protective coatings for commercial particulates

    DEFF Research Database (Denmark)

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


    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...

  16. Monitoring Gaseous and Particulate Air Pollutants near Major ...

    African Journals Online (AJOL)

    Air pollutants such as CO, CO2, NO, NO2, SO2, H2S) and suspended particulate matter (SPM) were determined using an active sampler for both dry and wet seasons. The results shows concentration of CO in the urban air ranging from 1.58 – 8.50 ppm during the dry season and 1.22 – 25.75 ppm for wet season, while CO2 ...


    African Journals Online (AJOL)



    Mar 21, 2017 ... Measurement of atmospheric particulate matter was carried out with a view to establish the potential influence of meteorological parameters such as wind speed, wind direction, air temperature, rainfall, relative humidity and global radiation on the mass concentration. Particulate matter (PM) in two size ...

  18. Colorimetry Technique for Scalable Characterization of Suspended Graphene. (United States)

    Cartamil-Bueno, Santiago J; Steeneken, Peter G; Centeno, Alba; Zurutuza, Amaia; van der Zant, Herre S J; Houri, Samer


    Previous statistical studies on the mechanical properties of chemical-vapor-deposited (CVD) suspended graphene membranes have been performed by means of measuring individual devices or with techniques that affect the material. Here, we present a colorimetry technique as a parallel, noninvasive, and affordable way of characterizing suspended graphene devices. We exploit Newton's rings interference patterns to study the deformation of a double-layer graphene drum 13.2 μm in diameter when a pressure step is applied. By studying the time evolution of the deformation, we find that filling the drum cavity with air is 2-5 times slower than when it is purged.

  19. Plutonium removal and diurnal variations of suspended sediment concentrations in the Great Miami River

    Energy Technology Data Exchange (ETDEWEB)

    Bobula, III, C. M.; Kennedy, C. W.; Bartelt, G. E.


    Effluent release experiments previously conducted downstream of the industrial outflal at Mound Laboratory have demonstrated that /sup 238/Pu which enters the aquatic environment as dissolved waste is rapidly adsorbed by suspended solids in the effluent pulse and that the dissolved/particulate distribution of /sup 238/Pu between release events congruent to 5 x 10/sup -2/./sup 3/ Reasonable estimates of the annual transport of /sup 239/ /sup 240/Pu based upon long-term discharge and sediment loading data have been reported for a large subwatershed in the upper reaches of the Great Miami River Basin. In this report data are given which characterize the short-term variability of suspended particulate transport downriver of a canal system contaminated with /sup 238/Pu.

  20. Improved efficiency of extraction of polycyclic aromatic hydrocarbons (PAHs) from the National Institute of Standards and Technology (NIST) Standard Reference Material Diesel Particulate Matter (SRM 2975) using accelerated solvent extraction. (United States)

    Masala, Silvia; Ahmed, Trifa; Bergvall, Christoffer; Westerholm, Roger


    The efficiency of extraction of polycyclic aromatic hydrocarbons (PAHs) with molecular masses of 252, 276, 278, 300, and 302 Da from standard reference material diesel particulate matter (SRM 2975) has been investigated using accelerated solvent extraction (ASE) with dichloromethane, toluene, methanol, and mixtures of toluene and methanol. Extraction of SRM 2975 using toluene/methanol (9:1, v/v) at maximum instrumental settings (200 °C, 20.7 MPa, and five extraction cycles) with 30-min extraction times resulted in the following elevations of the measured concentration when compared with the certified and reference concentrations reported by the National Institute of Standards and Technology (NIST): benzo[b]fluoranthene, 46%; benzo[k]fluoranthene, 137%; benzo[e]pyrene, 103%; benzo[a]pyrene, 1,570%; perylene, 37%; indeno[1,2,3-cd]pyrene, 41%; benzo[ghi]perylene, 163%; and coronene, 361%. The concentrations of the following PAHs were comparable to the reference values assigned by NIST: indeno[1,2,3-cd]fluoranthene, dibenz[a,h]anthracene, and picene. The measured concentration of dibenzo[a,e]-pyrene was lower than the information value reported by the NIST. The measured concentrations of other highly carcinogenic PAHs (dibenzo[a,l]pyrene, dibenzo[a,i]pyrene, and dibenzo[a,h]pyrene) in SRM 2975 are also reported. Comparison of measurements using the optimized ASE method and using similar conditions to those applied by the NIST for the assignment of PAH concentrations in SRM 2975 indicated that the higher values obtained in the present study were associated with more complete extraction of PAHs from the diesel particulate material. Re-extraction of the particulate samples demonstrated that the deuterated internal standards were more readily recovered than the native PAHs, which may explain the lower values reported by the NIST. The analytical results obtained in the study demonstrated that the efficient extraction of PAHs from SRM 2975 is a critical requirement for the

  1. Diesel particulate filter regeneration via resistive surface heating (United States)

    Gonze, Eugene V; Ament, Frank


    An exhaust system that processes exhaust generated by an engine is provided. The system includes: a particulate filter (PF) that filters particulates from the exhaust wherein an upstream end of the PF receives exhaust from the engine; and a grid of electrically resistive material that is applied to an exterior upstream surface of the PF and that selectively heats exhaust passing through the grid to initiate combustion of particulates within the PF.

  2. Biogeochemical characteristics of dissolved and particulate organic matter in Russian rivers entering the Arctic Ocean (United States)

    Lobbes, Jörg M.; Fitznar, Hans Peter; Kattner, Gerhard


    The biogeochemical signature of riverine matter in the Russian Arctic was investigated to establish a background for tracing terrestrial organic material in the Arctic Ocean. Elemental and lignin compositions of particulate and dissolved organic matter (POM, DOM), stable carbon isotope ratios of POM and nutrient concentrations are reported for 12 Russian rivers along 4000 km of coastline. The 12 rivers account for about 43% of the freshwater supply to the Arctic Ocean. Nine rivers drain both tundra and taiga areas and three rivers only tundra. Concentrations of nitrogenous nutrients and phosphate were low, whereas silicate values were generally high with only few exceptions. The concentrations of particulate organic carbon (POC) varied between 25.5 and 291 μmol/L C, contributing 0.4-2.1% to the total suspended sediment (TSS). Dissolved organic carbon (DOC) ranging from 230 to 1006 μmol/L C was on average eight times higher than POC. The concentrations of particulate and dissolved organic nitrogen were similar (ca. 11 μmol/L N) resulting in four times higher C/N ratios in the dissolved fraction (48) compared to the particulate fraction (11). The δ 13C ratios were uniform (-25.6 to -27.4‰) and similar in taiga and tundra draining rivers. The exclusively terrestrial component lignin, determined as lignin phenols after cupric oxide oxidation, ranged from 5.6 to 37.6 nmol/L in the particulate fraction and from 34 to 319 nmol/L in the dissolved fraction. The syringyl/vanillyl (S/V) and cinnamyl/vanillyl (C/V) ratios of the particulate and dissolved lignin phenols were significantly correlated with the proportion of tundra and taiga in the drainage areas. This is true despite different formation processes and diagenetic degree of POM and DOM, as evident from acid/aldehyde ratios of vanillyl phenols [(Ad/Al)v]. Export rates were calculated from the carbon and lignin data. The 12 rivers studied transport about 10 × 10 12 g of total organic carbon per year into the

  3. A study of particulates and metallic element concentrations in temple. (United States)

    Fang, G C; Lin, S J; Lee, J F; Chang, C C


    Concentrations of ambient suspended particulates were measured at Tzu Yun Yen temple in Taiwan (120 degrees , 34', 46.2''E, 24 degrees , 16', 17.1''N), where semi-open incense burning is characteristic. Many pilgrims from different areas with various beliefs visit the temple and burn incense. Samples were collected with a universal sampler used for measuring suspended particulate concentrations. Sampling period was from August 8, 2006, to October 6, 2006. The average PM(10) concentrations measured at the temple were 16% higher than 125 microg/m(3) (this value is the outdoor air quality standard according to Taiwan Environmental Protection Administration (EPA)). In coarse particulates (PM(2.5-10)), the mean metallic elements concentrations are in the order of Ca>Mg>Zn>Fe>Mn>Cr>Cu>Pb during weekend and weekday sampling. In addition, the fine particulates (PM(2.5)) mean metallic elements concentrations are in the order of Ca>Mg>Fe>Zn>Cr>Mn>Pb>Cu during weekend sampling and Ca>Fe>Mg>Zn>Cr>Mn>Pb>Cu during weekday sampling.

  4. Mutual relationships of suspended sediment, turbidity and visual clarity in New Zealand rivers

    Directory of Open Access Journals (Sweden)

    D. J. Ballantine


    Full Text Available Many river water quality monitoring programmes do not measure suspended particulate matter (SPM mass concentrations despite significant interest in its multiple effects on aquatic ecosystems. Regular monthly sampling usually intercepts rivers in baseflow when suspended sediment mass concentrations and fluxes are relatively low and not of particular interest. New Zealand’s National Rivers Water Quality Network (NRWQN is probably typical in not measuring SPM mass, although visual clarity and nephelometric turbidity are routinely measured. In order to better characterize SPM in NZ rivers, total suspended sediment (TSS was temporarily added to the NRWQN. Turbidity, visual clarity and TSS are mutually inter-related over all 77 sites, although with considerable data scatter. However, within individual rivers turbidity and visual clarity are typically fairly closely related to TSS and provide fair to excellent surrogates. Therefore, TSS need not be measured routinely because it can be estimated with sufficient precision for many purposes from visibility or turbidity.

  5. Batch fabrication of nanotubes suspended between microelectrodes

    DEFF Research Database (Denmark)

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


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

  6. New filter compositions for the analysis of airborne particulate and trace metals. (United States)

    Gelman, C; Mehta, D V; Meltzer, T H


    Characteristics are presented of various new filter materials of polyvinyl chloride--polyacrylonitrile, polyimide, polyaromatic, and of quartz fibers. These filters have been specifically developed for air sampling applications. Included in the presentation are comparative performance characteristics such as: infrared and ultraviolet spectra, inorganic and trace metals analyses, chemical compatibilities and reactivities with various liquids and gases, moisture pick-up, mass per unit area, mechanical properties (tensile strength and elongations), air flows/pressure drops, and particle retention efficiencies. Examples are presented of the increased acceptance of membrane filters in air analyses due to their simplifying tedious conventional procedures and their improvement of sensitivity, precision, and accuracies. Included are the ability of specific synthetic filters to impart optical transparency for analyses of asbestos and other fibers by transmission techniques using oil immersion or dispersion staining, the direct determination of silica on an acrylonitrile membrane by infrared, the direct determination of atmospheric particulate types and the concentrations of each. Other examples given are trace metal analyses by X-ray fluorescence, and gravimetric procedures and scanning electron microscopy techniques for analyses of suspended particulate matter.

  7. Electrically heated particulate filter regeneration using hydrocarbon adsorbents (United States)

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


    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 selectively heats exhaust passing through the upstream end to initiate combustion of particulates within the PF. A hydrocarbon adsorbent coating applied to the PF releases hydrocarbons into the exhaust to increase a temperature of the combustion of the particulates within the PF.

  8. An analysis of bedload and suspended load interactions (United States)

    Recking, alain; Navratil, Oldrich


    Several approaches were used to develop suspension equations. It includes semi-theoretical equations based on the convection diffusion equation (Einstein 1950; Van Rijn 1984; Camenen and Larson 2008; Julien 2010), semi-empirical tools based on energy concept (Velikanov 1954; Bagnold 1966), empirical adjustments (Prosser and Rusttomji 2000). One essential characteristic of all these equations is that most of them were developed by considering continuity between bedload and suspended load, and that the partitioning between these two modes of transport evolves progressively with increasing shear stress, which is the case for fine bed materials. The use of these equations is thus likely to be welcome in estuaries or lowland sandy rivers, but may be questionable in gravel-bed rivers and headwater streams where the bed is usually structured vertically and fine sediments potentially contributing to suspension are stored under a poorly mobile surface armour comprising coarse sediments. Thus one question this work aimed to answer is does the presence of an armour at the bed surface influence suspended load? This was investigated through a large field data set comprising instantaneous measurements of both bedload and suspension. We also considered the river characteristics, distinguishing between lowland rivers, gravel bed rivers and headwater streams. The results showed that a correlation exist between bedload and suspension for lowland and gravel bed rivers. This suggests that in gravel bed rivers a large part of the suspended load is fed by subsurface material, and depends on the remobilization of the surface material. No correlation was observed for head water streams where the sediment production is more likely related to hillslope processes. These results were used with a bedload transport equation for proposing a method for suspended load estimate. The method is rough, but especially for gravel bed rivers, it predicts suspended load reasonably well when compared to

  9. 76 FR 80982 - International Cyclotron, Inc., Hato Rey, Puerto Rico; Order Suspending Licensed Activities (United States)


    ...-0292] International Cyclotron, Inc., Hato Rey, Puerto Rico; Order Suspending Licensed Activities I International Cyclotron, Inc. (International Cyclotron; Licensee) is the holder of Byproduct Materials License... International Cyclotron submitted its NRC license application related to the cyclotron, it requested...

  10. Rippling instabilities in suspended nanoribbons (United States)

    Wang, Hailong; Upmanyu, Moneesh


    Morphology mediates the interplay between the structure and electronic transport in atomically thin nanoribbons such as graphene as the relaxation of edge stresses occurs preferentially via out-of-plane deflections. In the case of end-supported suspended nanoribbons that we study here, past experiments and computations have identified a range of equilibrium morphologies, in particular, for graphene flakes, yet a unified understanding of their relative stability remains elusive. Here, we employ atomic-scale simulations and a composite framework based on isotropic elastic plate theory to chart out the morphological stability space of suspended nanoribbons with respect to intrinsic (ribbon elasticity) and engineered (ribbon geometry) parameters, and the combination of edge and body actuation. The computations highlight a rich morphological shape space that can be naturally classified into two competing shapes, bendinglike and twistlike, depending on the distribution of ripples across the interacting edges. The linearized elastic framework yields exact solutions for these rippled shapes. For compressive edge stresses, the body strain emerges as a key variable that controls their relative stability and in extreme cases stabilizes coexisting transverse ripples. Tensile edge stresses lead to dimples within the ribbon core that decay into the edges, a feature of obvious significance for stretchable nanoelectronics. The interplay between geometry and mechanics that we report should serve as a key input for quantifying the transport along these ribbons.

  11. Combined technology for observing, understanding and predicting suspended particle transport and fate from anthropogenic discharges in coastal waters (United States)

    Davies, E. J.


    The combined observation, understanding and prediction of suspended particle transport and fate in coastal waters is essential for assessing environmental stresses that originate from anthropogenic sources. We present a toolbox consisting of an optics-based instrument suite, post-processing and analysis tools, and numerical models for understanding particle transport and fate, and its effect on the marine environment. We show results from a combined measurement and modelling campaign, focussed on understanding the transport of flocculating particulate material discharged into a Norwegian fjord, and demonstrate the application of this approach to real-time monitoring of drilling discharges in the vicinity of coral reefs. Unique measurements and images of suspended particulates, obtained from multiple water column profiles within a fjord, are presented. Initial model predictions of particle transport were used to highlight target areas for the field campaign, where model uncertainty was highest. Regular discharges of flocculating material were released into the fjord, requiring particle observations to span several orders of magnitude in size and concentration. This was achieved by combining data from a LISST-100, LISST-HOLO, and a bespoke Silhouette particle imaging system. Together, these instruments produced size distributions ranging from 2.5-10000microns. In-situ imaging proved essential in providing a realistic picture of the nature of the flocculated material, with many long, string-like flocs of several cm in length being advected hundreds of metres from their discharge location. Observations surrounding the discharge within this fjord system are used to help validate an improved particle transport model aimed at accurately accounting for flocculation, subsequent sedimentation and modifications to seabed bathymetry. The numerical formulation enhanced by this combined measurement and modelling approach is applicable for a wide variety of scenarios where human

  12. Removal of metals and water-insoluble materials from desalter emulsions

    Energy Technology Data Exchange (ETDEWEB)

    Goyal, S.K.; Mosby, J.F.; Treadman, J.E. II.


    A process for removing metals and insoluble materials from crude oil is described comprising the steps of: blending crude oil with water and desalting chemicals; charging the oil blend to a desalting chamber and passing it through an electrical field whereby agglomeration of suspended insoluble materials occurs and layers of clean oil, brine and oil-brine interface emulsion are formed; withdrawing the oil and brine; measuring the volume of the emulsion layer; withdrawing a portion of the emulsion layer; blending the withdrawn emulsion with up to 2 volumes of aromatic-rich hydrocarbon containing at least 20% aromatics by volume; maintaining the blend at a temperature of 100 to 300 F and a positive pressure; and subjecting the blend to a force of at least about 500 g, whereby oil free of at least 90% of suspended particulates and water results.

  13. Composição elementar do material particulado presente no aerossol atmosférico do município de Sete Lagoas, Minas Gerais Elemental composition of the particulate matter present in the atmospheric aerosols of Sete Lagoas, MG

    Directory of Open Access Journals (Sweden)

    Paula Guimarães Moura Queiroz


    Full Text Available The main objective of this study was the identification of sources generating particulate matter in the atmospheric aerosols of Sete Lagoas, Minas Gerais. The measurement of the mineral composition was accomplished by X-ray diffractometry and the elemental concentration by neutron activation analysis. The results showed that Al, Cl, Cu, Fe, K, Mg and Na are the predominant chemical elements in the total suspended particles (TPS. The presence of Na, Ba, Cl, Cu, Eu, Fe and Sm in those particles with aerodynamic diameter smaller than 10 µm (PM10, indicates that soil dust and ceramic and pig iron industries are the main sources of air quality degradation in the region.

  14. Particulate Release From Nanoparticle-Loaded Shape Memory Polymer Foams. (United States)

    Nathan, Adam L; Fletcher, Grace K; Monroe, Mary Beth B; Hwang, Wonjun; Herting, Scott M; Hasan, Sayyeda M; Keller, Brandis K; Maitland, Duncan J


    Highly porous, open-celled shape memory polymer (SMP) foams are being developed for a number of vascular occlusion devices. Applications include abdominal aortic and neurovascular aneurysm or peripheral vascular occlusion. A major concern with implanting these high surface area materials in the vasculature is the potential to generate unacceptable particulate burden, in terms of number, size, and composition. This study demonstrates that particulate numbers and sizes in SMP foams are in compliance with limits stated by the most relevant standard and guidance documents. Particulates were quantified in SMP foams as made, postreticulation, and after incorporating nanoparticles intended to increase material toughness and improve radiopacity. When concentrated particulate treatments were administered to fibroblasts, they exhibited high cell viability (100%). These results demonstrate that the SMP foams do not induce an unacceptable level of risk to potential vascular occlusion devices due to particulate generation.

  15. Chemical composition of sediments, suspended matter, river water and ground water of the Nile (Aswan-Sohag traverse). (United States)

    Dekov, V M; Komy, Z; Araújo, F; Van Put, A; Van Grieken, R


    Sediment, suspended matter, river water and ground water samples were collected at twelve sites in the drainage valley of the Nile River, around Sohag (Central Egypt) and close to the Aswan High Dam. Elemental composition of the river water (27 elements), ground water (eight elements), suspended matter (12 elements) and sediments (12 elements) was studied. Aswan High Dam construction, agricultural and industrial human activities have led to dramatic changes in the Nile River chemistry. Nowadays, the Nile River has the highest dissolved salt content among the major African rivers. Dissolved transport is a major process for Ca, K, Sr, Zn, Cu, Ni and V. Manganese, Fe and Cr are mainly carried by suspended matter. The Nile suspended matter is exhausted in almost all elements studied (except for Mn) compared to the world average river suspended matter. Along the course of the river, the distribution of elements in the suspended matter and sediments is generally controlled by natural processes: the relative importance of elemental transport phases; and the oxidation, precipitation and sedimentation of mineral species through the varying physico-chemical conditions of the environment. Pollution input in the Nile particulate load is not major, as compared to the natural inputs. Eight genetic particle types describe the composition of the Nile suspended matter and sediments: (1) biogenous-aeolian (or silica); (2) terrigenous (Fe-aluminosilicate); (3) authigenic (calcium carbonate); (4) biogenous (apatite); (5) authigenous-terrigenous (Fe-oxyhydroxide-montmorillonite); (6) diagenetic (iron-sulfide); (7) terrigenous (titanium oxide); (8) authigenous (Mn-Fe-oxyhydroxide).

  16. Self-Suspended Suspensions of Covalently Grafted Hairy Nanoparticles

    KAUST Repository

    Choudhury, Snehashis


    © 2015 American Chemical Society. Dispersions of small particles in liquids have been studied continuously for almost two centuries for their ability to simultaneously advance understanding of physical properties of fluids and their widespread use in applications. In both settings, the suspending (liquid) and suspended (solid) phases are normally distinct and uncoupled on long length and time scales. In this study, we report on the synthesis and physical properties of a novel family of covalently grafted nanoparticles that exist as self-suspended suspensions with high particle loadings. In such suspensions, we find that the grafted polymer chains exhibit unusual multiscale structural transitions and enhanced conformational stability on subnanometer and nanometer length scales. On mesoscopic length scales, the suspensions display exceptional homogeneity and colloidal stability. We attribute this feature to steric repulsions between grafted chains and the space-filling constraint on the tethered chains in the single-component self-suspended materials, which inhibits phase segregation. On macroscopic length scales, the suspensions exist as neat fluids that exhibit soft glassy rheology and, counterintuitively, enhanced elasticity with increasing temperature. This feature is discussed in terms of increased interpenetration of the grafted chains and jamming of the nanoparticles. (Chemical Presented).

  17. The mechanical behaviour of packed particulates

    Energy Technology Data Exchange (ETDEWEB)

    Dutton, R


    Within the Canadian Nuclear Fuel Waste Management program, the central concept is to package used fuel in containers that would be deposited in an underground vault in a plutonic rock formation. To provide internal mechanical support for the container, the reference design specifies it to be filled with a matrix of compacted particulate material (called 'packed particulate'), such as quartz sand granules. The focus of this report is on the mechanical properties of the packed-particulate material, based on information drawn from the extant literature. We first consider the packing density of particulate matrices to minimize the remnant porosity and maximize mechanical stability under conditions of external pressure. Practical methods, involving vibratory packing, are reviewed and recommendations made to select techniques to achieve optimum packing density. The behaviour of particulates under compressive loading has been of interest to the powder metallurgy industry (i.e., the manufacture of products from pressed/sintered metal and ceramic powders) since the early decades of this century. We review the evidence showing that in short timescales, stress induced compaction occurs by particle shuffling and rearrangement, elastic distortion, plastic yielding and microfracturing. Analytical expressions are available to describe these processes in a semiquantitative fashion. Time-dependent compaction, mainly via creep mechanisms, is more complex. Much of the theoretical and experimental information is confined to higher temperatures (> 500 degrees C), where deformation rates are more rapid. Thus, for the relatively low ambient temperatures of the waste container ({approx}100 degrees C), we require analytical techniques to extrapolate the collective particulate creep behaviour. This is largely accomplished by employing current theories of creep deformation, particularly in the form of Deformation Mechanism Maps, which allow estimation of creep rates over a wide

  18. Suspended 3D pyrolytic carbon microelectrodes for electrochemistry

    DEFF Research Database (Denmark)

    Hemanth, Suhith; Caviglia, Claudia; Keller, Stephan Sylvest


    Carbon microelectrodes have a wide range of applications because of their unique material properties and biocompatibility. This work presents the fabrication and characterization of suspended pyrolytic carbon microstructures serving as three-dimensional (3D) carbon microelectrodes for electrochem...... resistance as compared to 2D carbon electrodes. The higher sensitivity of 3D carbon microelectrodes for electrochemical sensing was illustrated by dopamine detection.......Carbon microelectrodes have a wide range of applications because of their unique material properties and biocompatibility. This work presents the fabrication and characterization of suspended pyrolytic carbon microstructures serving as three-dimensional (3D) carbon microelectrodes...... for electrochemical applications. A 3D polymer template in epoxy based photoresist (SU-8) was fabricated with multiple steps of UV photolithography and pyrolysed at 900 °C to obtain 3D carbon microelectrodes. The pyrolytic carbon microstructures were characterized by SEM, Raman spectroscopy and XPS to determine...

  19. Turbulence control of suspended matter aggregate size (United States)

    Jago, C. F.; Jones, S. E.; Rippeth, T. P.; Simpson, J. H.


    The size and properties of the aggregates which comprise suspended particulate matter (SPM) change on short time and length scales in shelf seas. There is experimental and theoretical evidence to suggest that turbulence plays a key role in aggregation but there is contradictory evidence with respect to disaggregation: it has been proposed that sinking stresses, rather than turbulent stresses, are the dominant control of disaggregation. But there is little observational evidence for turbulence control of particle properties. New observations are presented which provide compelling evidence for turbulence control of both aggregation and disaggregation. TKE dissipation and particle size were measured in situ at stratified sites in the northern North Sea in 110 m water depth during the period of weakening of the seasonal thermocline (in October/November) and in the Clyde Sea in 55 m water depth (April). There were similar vertical distributions of TKE dissipation E, SPM concentration C, and particle size D at both sites. At the base of the thermocline, there were minima in E and C, but a maximum in D, indicating that enhanced aggregation was occurring in this region of low turbulent stress. In the bottom mixed layer, E and C increased, while D decreased due to disaggregation in this region of increasing turbulent stress towards the seabed. Particles settling out of the low stress region at the base of the thermocline began to disaggregate when E increased to 3.2x10-6 watts m-2. D did not correlate directly with E because aggregation is a function of collision frequency (and hence of both C and E): this can be accounted for using a simplified theoretical aggregation model which treats flocs as self-similar fractal entities and allows simultaneous floc formation and break up, specified as functions of C and E. It was found that in the northern North Sea the measured D represents an equilibrium size predicted by the model, while in the Clyde Sea tidal variation in both C

  20. The fluvial flux of particulate organic matter from the UK : quantifying in-stream losses and carbon sinks.


    Worrall, F; Burt, T.P.; Howden, N.J.K.


    This study considers records of fluvial suspended sediment concentration and its organic matter content from across the United Kingdom from 1974 to 2010. Suspended sediment, mineral concentration and river flow data were used to estimate the particulate organic matter (POM) concentration and flux. Median annual POM flux from the UK was 1596 ktonnes/yr. The POM concentration significantly declined after the European Commission’s Urban Wastewater Directive was adopted in 1991 although the POM f...

  1. Univers de Particules

    CERN Multimedia

    CERN Video Productions


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

  2. 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)


    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.

  3. Modeling of particulate production in the SIRENS plasma disruption simulator

    Energy Technology Data Exchange (ETDEWEB)

    Sharpe, J.P. E-mail:; Merrill, B.J.; Petti, D.A.; Bourham, M.A.; Gilligan, J.G


    Modeling of the complex interplay among plasma physics, fluid mechanics, and aerosol dynamics is critical to providing a detailed understanding of the mechanisms responsible for particulate production from plasma-surface interaction in fusion devices. Plasma/fluid and aerosol models developed for analysis of disruption simulation experiments in the SIRENS high heat flux facility integrate the necessary mechanisms of plasma-material interaction, plasma and fluid flow, and particulate generation and transport. The model successfully predicts the size distribution of primary particulate generated in SIRENS disruption-induced material mobilization experiments.

  4. Avaliação da concentração de mercúrio em sedimentos e material particulado no rio Acre, estado do Acre, Brasil Mercury concentration assessment in botton sediments and suspended solids from Acre river, in the State of Acre, Brazil

    Directory of Open Access Journals (Sweden)

    Artur Fernando Silva Mascarenhas


    Full Text Available A avaliação dos teores de mercúrio em sistemas aquáticos sem influência direta de fontes antropogênicas conhecidas não tem sido conduzida com freqüência na região Amazônica. Visando contribuir para esclarecer a ocorrência de valores elevados de Hg em peixes consumidos pela população de Rio Branco - AC, o Instituto Evandro Chagas - IEC, realizou um estudo para quantificar os teores de Hg em sedimentos de fundo e material particulado no rio Acre e alguns afluentes, além da caracterização físico-química das águas entre as cidades de Brasiléia e Assis Brasil. As amostras de sedimentos foram peneiradas na fração Mercury levels assessment in aquatic systems areas without influences of antropogenic sources have not been well studied in the Amazon region. For the identification of the origin of high values of Hg in fish consumed by population of Rio Branco City - AC, the Evandro Chagas Institute - IEC, studied the mercury levels in sediments, suspended solids and studied also the physical-chemical characterization of waters, in the Acre river and also some in afluents, between Brasiléia and Assis Brasil cities. Bottom sediments samples were sieved to <250 mesh fraction after drying. The suspended solid was obtained by precipitation with Al2SO4. About 250 mg of the material was submitted the acid digestion and the determinations of Hg were made by Could Vapor Atomic Absorption Spectrometry. The physical-chemical parameters pH, electric conductivity, temperature and dissolved total solids, were studied in the field, by potenciometric methods. The Hg levels in bottom sediments range 0,018 and 0,184 mug g-1, mean of 0,054 ± 0,034 mug g-1, while the suspended solids varied between 0,067 and 0,220 mug g-1, average of 0,098 ± 0,037 mug g-1. The waters were slightly acid with pH varying among 5,80 - 6,95 and conductivity electric 151,60 - 1.151,00 muS cm-1. The mercury levels in the analyzed materials was below of standard levels for

  5. Spatial correlativity of atmospheric particulate components simultaneously collected in Japan. (United States)

    Funasaka, Kunihiro; Asakawa, Daichi; Oku, Yuichiro; Kishikawa, Naoya; Deguchi, Yuya; Sera, Nobuyuki; Seiyama, Tetsurou; Horasaki, Kazunori; Arashidani, Keiichi; Toriba, Akira; Hayakawa, Kazuichi; Watanabe, Masanari; Kataoka, Hiroyuki; Yamaguchi, Takako; Ikemori, Fumikazu; Inaba, Yohei; Tonokura, Kenichi; Akiyama, Masayuki; Kokunai, Osamu; Coulibaly, Souleymane; Hasei, Tomohiro; Watanabe, Tetsushi


    The simultaneous sampling of total suspended particles was performed at 14 sites in Japan during July 2008-June 2009. The spatial correlativity of each particulate composition toward Osaka was obtained for nine selected sites to overview the chemical composition and geographical distribution of particulate components across a wide range of areas nationwide. The spatial correlatives of atmospheric particulate components were extended to an even wider range of areas up to 950 km distance (meso-alpha scale region, >200 km) for a far-reaching distance analysis unique in the literature. Overall, the spatial correlations of ionic species and both organic and elemental carbons were significant, suggesting their shared advections, including their long-range transport from East Asia. Although sulfate ions are widely dispersed across Japan, such is not necessarily correlated with organic and elemental carbon, possibly indicating that the sulfate emission source, including long-range transport, differs from that of carbonaceous particulates. By contrast, the characteristics of spatial correlatives of metallic constituents vary; for example, particulate Pb and Cd show a significantly wide range of spatial correlatives to Osaka, while Mn-though limited to cities neighboring Osaka-shows significant spatial correlations. Other metallic constituents showed no significant spatial correlatives, indicating the effects of local pollutants. Moreover, the extent of the spatial dispersion of the particulate components and the relationships among chemical components were analyzed via factor analysis to highlight the effects of long-range inflow and local original emissions. In this treatment, 13 particulate components among the 19 measured were implicated in long-range transport.

  6. Particle size distribution of suspended solids in the Chesapeake Bay entrance and adjacent shelf waters (United States)

    Byrnes, M. R.; Oertel, G. F.


    Characteristics of suspended solids, including total suspended matter, total suspended inorganics, total suspended organics, particle size distribution, and the presence of the ten most prominent particle types were determined. Four research vessels simultaneously collected samples along four transects. Samples were collected within a 2-hour period that coincided with the maximum ebb penetration of Chesapeake Bay outwelling. The distribution of primary and secondary particle size modes indicate the presence of a surface or near-surface plume, possibly associated with three sources: (1) runoff, (2) resuspension of material within the Bay, and/or (3) resuspension of material in the area of shoals at the Bay mouth. Additional supportive evidence for this conclusion is illustrated with ocean color scanner data.

  7. Electron microscope observations of impact crater debris amongst contaminating particulates on materials surfaces exposed in space in low-Earth orbit (United States)

    Murr, L. E.; Rivas, J. M.; Quinones, S.; Niou, C.-S.; Advani, A. H.; Marquez, B.


    Debris particles extracted from a small sampling region on the leading edge of the Long Duration Exposure Facility (LDEF) spacecraft have been examined by analytical transmission electron microscopy and the elemental frequency observed by energy-dispersive X-ray spectrometry and compared with upper atmosphere (Earth) particle elemental frequency and the average elemental compositions of interplanetary dust particles. A much broader elemental distribution was observed for the exposed spacecraft surface debris milieu. Numerous metal microfragment analyses, particularly aluminum and stainless steel, were compared with scanning electron microscope observations-of impact crater features, and the corresponding elemental spectra on selected LDEF aluminium tray clamps and stainless steel bolts. The compositions and melt features for these impact craters and ejecta have been shown to be consistent with microcrystalline debris fragments in the case of aluminum, and these observations suggest an ever changing debris milieu on exposed surfaces for space craft and space system materials.

  8. Electron microscope observations of impact crater debris amongst contaminating particulates on materials surfaces exposed in space in low-Earth orbit (United States)

    Murr, L. E.; Rivas, J. M.; Quinones, S.; Niou, C.-S.; Advani, A. H.; Marquez, B.


    Debris particles extracted from a small sampling region on the leading edge of the Long Duration Exposure Facility (LDEF) spacecraft have been examined by analytical transmission electron microscopy and the elemental frequency observed by energy-dispersive X-ray spectrometry and compared with upper atmosphere (Earth) particle elemental frequency and the average elemental compositions of interplanetary dust particles. A much broader elemental distribution was observed for the exposed spacecraft surface debris milieu. Numerous metal microfragment analyses, particularly aluminum and stainless steel, were compared with scanning electron microscope observations-of impact crater features, and the corresponding elemental spectra on selected LDEF aluminium tray clamps and stainless steel bolts. The compositions and melt features for these impact craters and ejecta have been shown to be consistent with microcrystalline debris fragments in the case of aluminum, and these observations suggest an ever changing debris milieu on exposed surfaces for space craft and space system materials.

  9. "a" interfacial parameter in Nicolais-Narkis model for yield strength of polymer particulate nanocomposites as a function of material and interphase properties. (United States)

    Zare, Yasser


    In this paper, "a" interfacial parameter in Nicolais-Narkis model is expressed by thickness "ri" and strength "σi" of interphase between polymer and nanoparticles as well as material properties. "a" parameter is connected to "B1" interfacial parameter in modified Pukanszky model and the effects of "ri" and "σi" on "a" are explained. The negligible difference between "a" values calculated by fitting the experimental results to Nicolais-Narkis model and also, by "B1" results confirms the accurateness of the suggested relation between "a" and "B1" parameters. Additionally, an inverse relation is found between "a" and "B1" parameters for nanocomposites containing spherical nanoparticles. The results demonstrate that the slight levels of "ri" and "σi" data give a large value of "a" which indicates the poor interfacial adhesion. Copyright © 2016 Elsevier Inc. All rights reserved.

  10. Effect of a Particulate and a Putty-Like Tricalcium Phosphate-Based Bone-grafting Material on Bone Formation, Volume Stability and Osteogenic Marker Expression after Bilateral Sinus Floor Augmentation in Humans. (United States)

    Knabe, Christine; Adel-Khattab, Doaa; Kluk, Esther; Struck, Rainer; Stiller, Michael


    This study examines the effect of a hyaluronic acid (HyAc) containing tricalcium phosphate putty scaffold material (TCP-P) and of a particulate tricalcium phosphate (TCP-G) graft on bone formation, volume stability and osteogenic marker expression in biopsies sampled 6 months after bilateral sinus floor augmentation (SFA) in 7 patients applying a split-mouth design. 10% autogenous bone chips were added to the grafting material during surgery. The grain size of the TCP granules was 700 to 1400 µm for TCP-G and 125 to 250 µm and 500 to 700 µm (ratio 1:1) for TCP-P. Biopsies were processed for immunohistochemical analysis of resin-embedded sections. Sections were stained for collagen type I (Col I), alkaline phosphatase (ALP), osteocalcin (OC) and bone sialoprotein (BSP). Furthermore, the bone area and biomaterial area fraction were determined histomorphometrically. Cone-beam CT data recorded after SFA and 6 months later were used for calculating the graft volume at these two time points. TCP-P displayed more advantageous surgical handling properties and a significantly greater bone area fraction and smaller biomaterial area fraction. This was accompanied by significantly greater expression of Col I and BSP and in osteoblasts and osteoid and a less pronounced reduction in grafting volume with TCP-P. SFA using both types of materials resulted in formation of sufficient bone volume for facilitating stable dental implant placement with all dental implants having been in function without any complications for 6 years. Since TCP-P displayed superior surgical handling properties and greater bone formation than TCP-G, without the HyAc hydrogel matrix having any adverse effect on bone formation or graft volume stability, TCP-P can be regarded as excellent grafting material for SFA in a clinical setting. The greater bone formation observed with TCP-P may be related to the difference in grain size of the TCP granules and/or the addition of the HyAc.

  11. Rigid particulate matter sensor (United States)

    Hall, Matthew [Austin, TX


    A sensor to detect particulate matter. The sensor includes a first rigid tube, a second rigid tube, a detection surface electrode, and a bias surface electrode. The second rigid tube is mounted substantially parallel to the first rigid tube. The detection surface electrode is disposed on an outer surface of the first rigid tube. The detection surface electrode is disposed to face the second rigid tube. The bias surface electrode is disposed on an outer surface of the second rigid tube. The bias surface electrode is disposed to face the detection surface electrode on the first rigid tube. An air gap exists between the detection surface electrode and the bias surface electrode to allow particulate matter within an exhaust stream to flow between the detection and bias surface electrodes.

  12. Health effects of atmospheric particulates: a medical geology perspective. (United States)

    Duzgoren-Aydin, Nurdan S


    In this review, atmospheric particulates as composite airborne earth materials often containing both natural and anthropogenic components were examined in the context of medical geology. Despite a vast number of both experimental and epidemiological studies confirming the direct and indirect links between atmospheric particulates and human health, the exact nature of mechanisms affecting the particulate-induced pathogenesis largely remains unexplored. Future in depth research on these areas would be most successful if potential mechanisms are examined with reference to the physical (e.g., size, shape and surface), chemical, mineralogical and source characteristics of particulate matters. The underlying goal of this review was to present the relevant terminology and processes proposed in the literature to explain the interfaces and interactions between atmospheric particles and human body within the framework of "atmospheric particle cycles." The complexities of the interactions were demonstrated through case studies focusing on particulate matter air pollution and malignant mesothelioma occurrences due to environmental exposure to erionite-a fibrous zeolite mineral. There is an urgent need for a standard protocol or speciation methods applicable to earth-materials to guide and streamline studies on etiology of mineral-induced diseases. This protocol or speciation methods should provide relevant procedures to determine the level and extent of physical, chemical and mineralogical heterogeneity of particulate matters as well as quantitative in-situ particulate characteristics.

  13. Pre-aged soil organic carbon as a major component of the Yellow River suspended load: Regional significance and global relevance (United States)

    Tao, Shuqin; Eglinton, Timothy I.; Montluçon, Daniel B.; McIntyre, Cameron; Zhao, Meixun


    Large rivers connect the continents and the oceans, and corresponding material fluxes have a global impact on marine biogeochemistry. The Yellow River transports vast quantities of suspended sediments to the ocean, yet the nature of the particulate organic carbon (POC) carried by this system is not well known. The focus of this study is to characterize the sources, composition and age of suspended POC collected near the terminus of this river system, focusing on the abundance and carbon isotopic composition (13C and 14C) of specific biomarkers. The concentrations of vascular plant wax lipids (long-chain (≥C24) n-alkanes, n-fatty acids) and POC co-varied with total suspended solid (TSS) concentrations, indicating that both were controlled by the overall terrestrial sediment flux. POC exhibited relatively uniform δ13C values (-23.8 to -24.2‰), and old radiocarbon ages (4000-4640 yr). However, different biomarkers exhibited a wide range of 14C ages. Short-chain (C16, C18) fatty acid 14C ages were variable but generally the youngest organic components (from 502 yr to modern), suggesting they reflect recently biosynthesized material. Lignin phenol 14C ages were also variable and relatively young (1070 yr to modern), suggesting rapid export of carbon from terrestrial primary production. In contrast, long-chain plant wax lipids display relatively uniform and significantly older 14C ages (1500-1800 yr), likely reflecting inputs of pre-aged, mineral-associated soil OC from the Yellow River drainage basin. Even-carbon-numbered n-alkanes yielded the oldest 14C ages (up to 26 000 yr), revealing the presence of fossil (petrogenic) OC. Two isotopic mass balance approaches were explored to quantitively apportion different OC sources in Yellow River suspended sediments. Results indicate that the dominant component of POC (53-57%) is substantially pre-aged (1510-1770 yr), and likely sourced from the extensive loess-paleosol deposits outcropping within the drainage basin. Of


    Energy Technology Data Exchange (ETDEWEB)

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


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

  15. Influences of suspended particles on the runoff of pesticides from an agricultural field at Askim, SE-Norway. (United States)

    Wu, Q; Riise, G; Lundekvam, H; Mulder, J; Haugen, L E


    Field and laboratory experiments were conducted to study the loss of particles from agricultural fields, and the role of suspended particles in carrying pesticides in surface runoff and drainage water. Propiconazole, a widely used fungicide was applied to experimental fields located at Askim, SE-Norway. Samples from surface runoff and drainage water were collected and analyzed for sediment mass, pesticides, particulate and dissolved organic carbon through a whole year. The surface soil and the runoff material were characterized by its particle size distribution, organic carbon content in size fractions and its ability to bind propiconazole. The results show that (1) particle runoff mostly occurred during the rainfall event shortly after harrowing in autumn. The highest particle concentration observed in the surface runoff water was 4600 mg l(-1), and in the drainage water 1130 mg l(-1); (2) the erosion of surface soil is size selective. The runoff sediment contained finer particle/aggregates rich in organic matter compared to its original surface soil; (3) the distribution coefficient (Kd) of propiconazole was significantly higher in the runoff sediment than in the parent soil. According to our calculation, particle-bound propiconazole can represent up to 23% of the total amount of propiconazole in a water sample with a sediment concentration of 7600 mg l(-1), which will significantly influence the transport behavior of the pesticide.

  16. Particulate photocatalysts for overall water splitting (United States)

    Chen, Shanshan; Takata, Tsuyoshi; Domen, Kazunari


    The conversion of solar energy to chemical energy is a promising way of generating renewable energy. Hydrogen production by means of water splitting over semiconductor photocatalysts is a simple, cost-effective approach to large-scale solar hydrogen synthesis. Since the discovery of the Honda-Fujishima effect, considerable progress has been made in this field, and numerous photocatalytic materials and water-splitting systems have been developed. In this Review, we summarize existing water-splitting systems based on particulate photocatalysts, focusing on the main components: light-harvesting semiconductors and co-catalysts. The essential design principles of the materials employed for overall water-splitting systems based on one-step and two-step photoexcitation are also discussed, concentrating on three elementary processes: photoabsorption, charge transfer and surface catalytic reactions. Finally, we outline challenges and potential advances associated with solar water splitting by particulate photocatalysts for future commercial applications.

  17. Filtration and resuspension of particulate matter and phytoplankton on an intertidal mussel bed in the Oosterschelde estuary (SW Netherlands)

    NARCIS (Netherlands)

    Prins, T.C.; Smaal, A.C.; Pouwer, A.J.; Dankers, N.


    In situ measurements were carried out on an intertidal mussel bed in the Oosterschelde estuary, SW Netherlands. Exchange of suspended particulate matter and phytoplankton between the water column and the mussel bed was measured with a Benthic Ecosystem Tunnel. In situ clearance rates of the mussel

  18. 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


    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

  19. Measuring a Pig's Preference for Suspended Toys by Using an Automated Recording Technique

    NARCIS (Netherlands)

    Zonderland, J.J.; Vermeer, H.M.; Vereijken, P.F.G.; Spoolder, H.A.M.


    Not all suspended materials for finishing pigs are equally suited to meet the natural behavior of the animal, but the required physical properties of the toys have yet to be identified. The present study aimed to develop a labor saving electronic recording device for animal-material interactions.

  20. Electron beam analysis of particulate cometary material (United States)

    Bradley, John


    Electron microscopy will be useful for characterization of inorganic dust grains in returned comet nucleus samples. The choice of instrument(s) will depend primarily on the nature of the samples, but ultimately a variety of electron-beam methods could be employed. Scanning and analytical (transmission) electron microscopy are the logical choise for morphological, mineralogical, and bulk chemical analyses of dust grains removed from ices. It may also be possible to examine unmelted ice/dust mixtures using an environmental scanning electron microscope equipped with a cryo-transfer unit and a cold stage. Electron microscopic observations of comet nuclei might include: (1) porosities of dust grains; (2) morphologies and microstructures of individual mineral grains; (3) relative abundances of olivine, pyroxene, and glass; and (4) the presence of phases that might have resulted from aqueous alteration (layer silicates, carbonates, sulfates).

  1. Microbial biomass on particulate organic matter in seawater of the euphotic zone. (United States)

    Seki, H


    Microbial biomass on suspended organic matter in seawater of the euphotic zone of Saanich Inlet was investigated. The viable microorganisms were measured by the glucose-uptake method. Microbial carbon on particulate organic matter in seawater was determined to be, on the average, 9.9 mug of C/liter, and there was a regression relationship as y = 0.0062 x - 1.79 with an unbiased variance V(yx) = 0.38, where x = particulate organic carbon in seawater (micrograms of C/liter) and y = logarithm of microbial carbon (micrograms of C/liter).

  2. Introduction to suspended-sediment sampling (United States)

    Nolan, K. Michael; Gray, John R.; Glysson, G. Douglas


    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

  3. Airborne Particulate Threat Assessment

    Energy Technology Data Exchange (ETDEWEB)

    Patrick Treado; Oksana Klueva; Jeffrey Beckstead


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

  4. Intrauterine and Early Postnatal Exposure to Particulate Air Pollution and Kawasaki Disease: A Nationwide Longitudinal Survey in Japan. (United States)

    Yorifuji, Takashi; Tsukahara, Hirokazu; Kashima, Saori; Doi, Hiroyuki


    To examine the effects of prenatal and postnatal exposure to particulate matter on Kawasaki disease (KD) occurrence, using data from a nationwide population-based longitudinal survey in Japan that began in 2010. Prenatal and postnatal suspended particulate matter concentrations were obtained at municipality level and assigned to participants based on their municipality of birth. We analyzed data from 30 367 participants with data on either exposure period. We used hospital admission for KD from 6 to 30 months of age as the main outcome of interest. We conducted a multilevel logistic regression analysis, adjusting for individual and municipality-level variables. Children who were exposed to higher levels of suspended particulate matter, in particular during pregnancy, were more likely to be hospitalized for KD. The ORs for ≥25 µg/m3 exposure compared with Japan. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. Salinity and suspended matter variations in the Tay estuary (United States)

    McManus, John


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

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

    Directory of Open Access Journals (Sweden)

    Mohammad W. Kadi


    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.

  7. Shock Wave Structure in Particulate Composites (United States)

    Rauls, Michael; Ravichandran, Guruswami


    Shock wave experiments are conducted on a particulate composite consisting of a polymethyl methacrylate (PMMA) matrix reinforced by glass beads. Such a composite with an impedance mismatch of 4.3 closely mimics heterogeneous solids of interest such as concrete and energetic materials. The composite samples are prepared using a compression molding process. The structure and particle velocity rise times of the shocks are examined using forward ballistic experiments. Reverse ballistic experiments are used to track how the interface density influences velocity overshoot above the steady state particle velocity. The effects of particle size (0.1 to 1 mm) and volume fraction of glass beads (30-40%) on the structure of the leading shock wave are investigated. It is observed that the rise time increases with increasing particle size and scales linearly for the range of particle sizes considered here. Results from numerical simulations using CTH are compared with experimental results to gain insights into wave propagation in heterogeneous particulate composites.

  8. 78 FR 8066 - Method for the Determination of Lead in Total Suspended Particulate Matter (United States)


    ... fountain or eye wash bottle be available during performance of this method. An eye wash bottle has a spout that covers the eye. If acid or any other corrosive gets into the eye, the water in this bottle is... threaded caps for extraction and storage, SCP Science DigiTUBE Item No. 010- 500-063, or equivalent...

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


    ... extraction, and also knowledge in the recognition and in the correction of spectral, chemical and physical... improved extraction methods that are now available with improved precision, sample throughput, and extraction efficiency; (2) address advances in measurement technology that have occurred since promulgation...

  10. 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.

    Institute of Oceanography, Goa 403 004, I n dia 4 M.S. University of Baroda, Vadodara 390 002, India Nitrogen concentration and its isotopic composition in surface su spended matter have been measured at 24 di f- ferent loc a tions during..., primarily the aste r oids and occasionally Mars and the Moon. They also pr o vide information about the energetic environment in the inte r- planetary space where they spend a considerable p e riod of time, ranging from less than a million years to a few...

  11. Clinical evaluation of the combination of anorganic bovine-derived hydroxyapatite matrix/cell-binding peptide (P-15) in particulate and hydrogel form as a bone replacement graft material in human periodontal osseous defects: 6-month reentry controlled clinical study. (United States)

    Matos, Sérgio M; Guerra, Fernando A; Krauser, Jack; Marques, Francisco; Ermida, Jorge M; Sanz, Mariano


    This prospective, randomized, controlled clinical trial study compared the clinical outcomes of the biomaterial anorganic bovine-derived hydroxyapatite matrix/cell-binding peptide (ABM/P-15) as a biocompatible hydrogel carrier consisting of carboxymethylcellulose and glycerol or in particulate form when used as a bone replacement graft in the treatment of human periodontal infrabony defects. Nineteen patients with advanced chronic periodontitis were recruited. All patients had at least two non-adjacent intrabony osseous defects > or = 3 mm after completion of cause-related periodontal therapy. The surgical procedures included access flaps for root instrumentation and filling the defect with ABM/P-15 in hydrogel or particulate form. Reentry access flap surgery was performed at 6 months. Changes in soft and hard tissue outcome measurements between baseline and 6 months were evaluated in all defects. At 6 months, no significant differences between ABM/P-15 hydrogel and ABM/P-15 particulate were demonstrated for the amount of defect fill (3.10 +/- 0.85 mm [75.0%] versus 3.09 +/- 1.11 mm [73.7%], respectively) or defect resolution (85.8% versus 81.9%). Changes in soft tissue clinical outcomes did not show significant differences between the treatments. This trial failed to demonstrate superiority of the novel ABM/P-15 hydrogel therapeutic modality over the standard ABM/ P-15 particulate graft in the treatment of intrabony periodontal defects.

  12. Tropical river suspended sediment and solute dynamics in storms during an extreme drought (United States)

    Clark, Kathryn E.; Shanley, James B.; Scholl, Martha A.; Perdrial, Nicolas; Perdrial, Julia N.; Plante, Alain F.; McDowell, William H.


    Droughts, which can strongly affect both hydrologic and biogeochemical systems, are projected to become more prevalent in the tropics in the future. We assessed the effects of an extreme drought during 2015 on stream water composition in the Luquillo Mountains of Puerto Rico. We demonstrated that drought base flow in the months leading up to the study was sourced from trade-wind orographic rainfall, suggesting a resistance to the effects of an otherwise extreme drought. In two catchments (Mameyes and Icacos), we sampled a series of four rewetting events that partially alleviated the drought. We collected and analyzed dissolved constituents (major cations and anions, organic carbon, and nitrogen) and suspended sediment (inorganic and organic matter (particulate organic carbon and particulate nitrogen)). The rivers appeared to be resistant to extreme drought, recovering quickly upon rewetting, as (1) the concentration-discharge (C-Q) relationships deviated little from the long-term patterns; (2) "new water" dominated streamflow during the latter events; (3) suspended sediment sources had accumulated in the channel during the drought flushed out during the initial events; and (4) the severity of the drought, as measured by the US drought monitor, was reduced dramatically after the rewetting events. Through this interdisciplinary study, we were able to investigate the impact of extreme drought through rewetting events on the river biogeochemistry.

  13. Tropical river suspended sediment and solute dynamics in storms during an extreme drought (United States)

    Clark, Kathryn E.; Shanley, James B.; Scholl, Martha A.; Perdrial, Nicolas; Perdrial, Julia N.; Plante, Alain F.; McDowell, William H.


    Droughts, which can strongly affect both hydrologic and biogeochemical systems, are projected to become more prevalent in the tropics in the future. We assessed the effects of an extreme drought during 2015 on stream water composition in the Luquillo Mountains of Puerto Rico. We demonstrated that drought base flow in the months leading up to the study was sourced from trade-wind orographic rainfall, suggesting a resistance to the effects of an otherwise extreme drought. In two catchments (Mameyes and Icacos), we sampled a series of four rewetting events that partially alleviated the drought. We collected and analyzed dissolved constituents (major cations and anions, organic carbon, and nitrogen) and suspended sediment (inorganic and organic matter (particulate organic carbon and particulate nitrogen)). The rivers appeared to be resistant to extreme drought, recovering quickly upon rewetting, as (1) the concentration-discharge (C-Q) relationships deviated little from the long-term patterns; (2) “new water” dominated streamflow during the latter events; (3) suspended sediment sources had accumulated in the channel during the drought flushed out during the initial events; and (4) the severity of the drought, as measured by the US drought monitor, was reduced dramatically after the rewetting events. Through this interdisciplinary study, we were able to investigate the impact of extreme drought through rewetting events on the river biogeochemistry.

  14. Monitoreo de emisiones de material particulado de chimeneas de generadores de vapor de la industria azucarera en Tucumán, R. Argentina Monitoring of effluent particulate matter emitted by sugarcane factory stacks in Tucumán

    Directory of Open Access Journals (Sweden)

    Marcos A. Golato


    Full Text Available Durante las moliendas en los años 2008, 2009, 2010 y 2011, se realizaron mediciones de las concentraciones de material particulado total (MPT en las emisiones de chimeneas de calderas de la industria azucarera, en Tucumán, R. Argentina. El objetivo de este trabajo fue monitorear la evolución de la concentración y emisión de MPT y observar la influencia de los sistemas de filtrado instalados en las chimeneas de las mencionadas unidades. Se ilustran los datos de las emisiones de MPT obtenidas en los años indicados, con valores promedio por caldera de 58,5 kg/h, 33,6 kg/h, 47,6 kg/h y 33,9 kg/h, respectivamente. Asimismo, este estudio muestra un seguimiento minucioso de un grupo de calderas bagaceras, para determinar la evolución de las emisiones en función de las variables de operación características de esas calderas. Los resultados demostraron la influencia del mantenimiento y de la correcta operación de los equipos de filtrado en la calidad de los gases que fluyen por las chimeneas. Se estudió la influencia de los índices característicos de diseño de los lavadores de gases en la concentración de partículas. Se observó que se ha logrado un menor impacto ambiental a lo largo del tiempo analizado.Total particulate matter (TPM concentrations were measured in stack fumes from sugar factory steam generating boilers in Tucumán in 2008, 2009, 2010 and 2011. The objective of this work was to monitor the evolution of TPM concentrations and emissions and observe the efficiency of filtration systems used in sugarcane factory stacks. Average values of 58.5 kg/h, 33.6 kg/h, 47.6 kg/h and 33.9 kg/h were obtained in 2008, 2009, 2010 and 2011, respectively. Bagasse boilers were also meticulously surveyed to obtain data of the evolution of emissions in relation to specific operation variables of the boilers. Data concerning the quality of effluent gasses from the stacks demonstrated the influence of maintaining and correctly using filtration

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

    Energy Technology Data Exchange (ETDEWEB)

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


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

  16. 9 CFR 201.81 - Suspended registrants. (United States)


    ... 201.81 Animals and Animal Products GRAIN INSPECTION, PACKERS AND STOCKYARDS ADMINISTRATION (PACKERS AND STOCKYARDS PROGRAMS), DEPARTMENT OF AGRICULTURE REGULATIONS UNDER THE PACKERS AND STOCKYARDS ACT Services § 201.81 Suspended registrants. No stockyard owner, packer, market agency, or dealer shall employ...

  17. Electrodialytic remediation of suspended mine tailings

    DEFF Research Database (Denmark)

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


    experiment at 40 mA, with approximately 137.5 g mine tailings on dry basis. The removal for a static (baseline) experiment only amounted 15% when passing approximately the same amount of charge through 130 g of mine tailings. The use of air bubbling to keep the tailings suspended increased the removal...

  18. Suspended sediment concentration and particle size distribution ...

    Indian Academy of Sciences (India)

    face area, shape, minerals and source) and conse- quent interaction with heavy metal concentrations. (HMCs). Recent studies have shown a growing awareness of the wider environmental significance of the suspended sediment loads transported by rivers and streams. This includes the importance of fine grain sediment in ...

  19. A depth integrated model for suspended transport

    NARCIS (Netherlands)

    Galappatti, R.


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

  20. The Shape of Breasts Suspended in Liquid

    NARCIS (Netherlands)

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


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

  1. Flow Laminarization and Acceleration by Suspended Particles

    NARCIS (Netherlands)

    Bertsch, M.; Hulshof, J.; Prostokishin, V.M.


    In [Comm. Appl. Math. Comput. Sci., 4(2009), pp. 153-175], Barenblatt presents a model for partial laminarization and acceleration of shear flows by the presence of suspended particles of different sizes, and provides a formal asymptotic analysis of the resulting velocity equation. In the present

  2. Emulsifying and Suspending Properties of Enterolobium ...

    African Journals Online (AJOL)

    Background:The thermodynamic instability of emulsions and suspensions necessitate the incorporation of emulsifiers and suspending agents respectively, in order to stabilize the formulations and ensure administration of accurate doses. Objective:Enterolobium cyclocarpum gum was characterized and evaluated for its ...

  3. Particle Size Characteristics of Fluvial Suspended Sediment in Proglacial Streams, King George Island, South Shetland Island (United States)

    Szymczak, Ewa


    In this study, the characterization of particle size distribution of suspended sediment that is transported by streams (Ornithologist Creek, Ecology Glacier Creeks, Petrified Forest Creek, Czech Creek, Vanishing Creek, Italian Creek) in the area of the Arctowski Polish Antarctic Station is presented. During the first period of the summer season, the aforementioned streams are supplied by the melting snow fields, while later on, by thawing permafrost. The water samples were collected from the streams at monthly intervals during the Antarctic summer season (January - March) of 2016. The particle size distribution was measured in the laboratory with a LISST-25X laser diffraction particle size analyser. According to Sequoia Scientific Inc., LISST-25X can measure particle sizes (Sauter Mean Diameter) between 2.50 and 500 μm. The results of particle size measurements were analysed in relation to flow velocity (0.18–0.89 m/s), the cross-sectional parameters of the streams, suspended sediment concentration (0.06–167.22 mg/dm3) and the content of particulate organic matter (9.8–84.85%). Overall, the mean particle size ranged from 28.8 to 136 μm. The grain size of well-sorted sediments ranged from 0.076 to 0.57, with the skewness and kurtosis values varying from -0.1 to 0.4, and from 0.67 to 1.3, respectively. Based on the particle size characteristics of suspended sediment, the streams were divided into two groups. For most of the streams, the sediment was very well sorted, while fine sand and very fine sand were dominant fractions displaying symmetric and platykurtic distributions, respectively. Only in two streams, the suspended sediment consisted of silt-size grains, well or moderately well sorted, with coarse-skewness and mostly mesokurtic distribution. The C-M chart suggested that the transportation processes of suspended sediment included the suspended mode only. The grain-size distribution of suspended sediment was mainly influenced by the stream runoff

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

    Energy Technology Data Exchange (ETDEWEB)

    Everard, M.; Denny, P.


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

  5. Suspended Sediment and Phosphorus Removal in a Woodchip Filter System Treating Agricultural Wash Water. (United States)

    Choudhury, Tahina; Robertson, Will Dean; Finnigan, Darryl S


    Woodchip filters have received attention in recent years for their ability to sustain denitrification activity across multiyear time frames. However, in some freshwater aquatic ecosystems, P rather than N is the nutrient considered most responsible for eutrophication. Previous studies have indicated that woodchip filters have limited ability to remove dissolved P, but in agricultural terrain, P export in watercourses is often dominated by particulate P (PP). Woodchip media, because of their high porosity and permeability and the surface roughness of the particles, could be effective for PP removal. In this study, we tested a woodchip filter for its ability to remove suspended sediment and associated PP at a farm in southern Ontario, Canada, where vegetable wash water with extremely high total suspended solids (TSS) was generated. The treatment system consisted of a 12.3-m concrete sedimentation tank and a slightly larger woodchip filter (16.1 m) installed in a subsurface trench. During 7 mo of full-scale operation, treating 10.8 m d, the filter system removed 71% of influent total P (TP) averaging 8.8 mg L and 99% of TSS averaging 5800 mg L, with most of the removal occurring in the tank and a lesser amount (6-16%) occurring in the woodchip filter. Almost all of the TP removal was associated with PP (91% removal) because dissolved P, averaging 1.5 mg L in the wash water, was little changed. Woodchip filters, when coupled with a solids settling tank, have the potential to provide high-capacity, low-maintenance treatment of suspended solids and associated particulate P in turbid waters. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  6. Sources of particulate organic matter in rivers from the continental usa: lignin phenol and stable carbon isotope compositions (United States)

    Onstad, Gretchen D.; Canfield, Donald E.; Quay, Paul D.; Hedges, John I.


    The origins and forms of particulate organic matter (POM) suspended in rivers are major considerations in assessing how fluvial materials integrate landscape and climate properties and ultimately record these characteristics in marine sedimentary deposits. We examined the elemental, stable carbon isotope and lignin-phenol compositions of well-characterized samples of suspended POM collected from rivers draining the south central United States. The atomic C/N ratios of 17 fine-grained samples (˜11 ± 2, n = 17) are similar to those reported worldwide for texturally similar soil and riverine POM. The corresponding δ 13C values vary from -18.5 to -26.4‰, in patterns that correspond to the relative abundances of C3 and C4 plants in the drainage basins, and hence to temperature and hydrologic patterns. Lignin-phenol yields from 12 samples indicate input of angiosperm-rich plant materials in distributions that also reflect upstream climate and vegetation. The lignin associated with these plant remains has been substantially degraded, as is typical of soil organic matter. The mass- and surface-area-normalized organic carbon contents of the river-borne POM also correspond to drainage basin properties in patterns characteristic of soils. These results indicate that highly degraded soil organic matter is a major component of fine-grained POM transported by rivers of the central US. The Mississippi River currently discharges "heavy" (δ 13C ≈ -20‰) lignin-poor POM. The isotopic composition of this organic matter is difficult to distinguish from marine plankton remains in fine-grained sediments of the northern Gulf of Mexico, whose isotopic compositions have been previously interpreted to broadly indicate limited offshore transport of terrigenous organic matter.


    Energy Technology Data Exchange (ETDEWEB)



    This quarterly report describes technical activities performed under Contract No. DE-AC21-94MC31160. The analyses of hot gas stream cleanup (HGCU) ashes and descriptions of filter performance studied under Task 1 of this contract are designed to address problems with filter operation that are apparently linked to characteristics of the collected ash. This report includes summaries of analyses performed on particulate samples from Sierra Pacific Power Company's Pinon Pine Power Project. This report also reviews the status of the HGCU data bank of ash and char characteristics, and plans for enhancing the data bank with interactive querying of measured particulate properties. Task 1 plans for the remainder of the project include completion and delivery of the HGCU data bank. Task 2 of this project concerns the testing and failure analyses of new and used filter elements and filter materials. Task 2 work during the past quarter included preliminary testing of two materials. One material tested was the soft candle filter manufactured by CGC and supplied by ABB. The other material was N610/mullite manufactured by Albany International (AIT).

  8. Materialism. (United States)

    Melnyk, Andrew


    Materialism is nearly universally assumed by cognitive scientists. Intuitively, materialism says that a person's mental states are nothing over and above his or her material states, while dualism denies this. Philosophers have introduced concepts (e.g., realization and supervenience) to assist in formulating the theses of materialism and dualism with more precision, and distinguished among importantly different versions of each view (e.g., eliminative materialism, substance dualism, and emergentism). They have also clarified the logic of arguments that use empirical findings to support materialism. Finally, they have devised various objections to materialism, objections that therefore serve also as arguments for dualism. These objections typically center around two features of mental states that materialism has had trouble in accommodating. The first feature is intentionality, the property of representing, or being about, objects, properties, and states of affairs external to the mental states. The second feature is phenomenal consciousness, the property possessed by many mental states of there being something it is like for the subject of the mental state to be in that mental state. WIREs Cogn Sci 2012, 3:281-292. doi: 10.1002/wcs.1174 For further resources related to this article, please visit the WIREs website. Copyright © 2012 John Wiley & Sons, Ltd.

  9. 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.


    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.

  10. Energy content of suspended detritus from Arabian Sea

    Digital Repository Service at National Institute of Oceanography (India)

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

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

  11. Suspended sediment concentration and particle size distribution ...

    Indian Academy of Sciences (India)

    ... particle size distribution (PSD) were correlated with HMC by using bivariate and multivariate regression models. Proposed models were then selected based on statistical criteria. The results showed high correlation between dissolved and particulate chromium content with efficiency coefficients beyond 77% ( > 0.001).

  12. Riverine Particulate Organic Carbon From a Pristine, Active Mountain Belt: The Importance of Vegetation and Landslides (United States)

    Hilton, R. G.; Hovius, N.; Galy, A.


    The erosion and transfer of terrestrial organic carbon is an important component in the carbon cycle. The sequestration of this material in sedimentary basins may influence global climate. Mountain rivers play a crucial role in the routing of Particulate Organic Carbon (POC) because they have high sediment production rates, small storage potential and tendency to discharge sediment to the oceans at very high concentrations. We present new constraints on the sourcing and transfer of POC in the tectonically active Southern Alps of New Zealand, where anthropogenic disturbance is minimal. Riverine POC can be derived from bedrock (in the form of sedimentary kerogen), standing biomass and soils. In active mountain belts, landsliding dominates sediment production and transfer of POC from hillslopes to river channels. Landslide debris fans, river suspended load and bedload, and bedrock were sampled in catchments draining the rapidly eroding western Southern Alps, in order to assess the sourcing and transfer of POC. Samples were analyzed for percent organic carbon (Corg), percent nitrogen (N_ {org) and δ13C. Using C/N and δ13C as source proxies, we have determined the main sources of the POC. Landslide debris has Corg ~ 0.15% to 2.77%. The sand, silt and clay fractions of this material all have C/N ~ 10 to 40 and δ13C ~ -20‰ to -28‰. This indicates that POC in landslide debris is dominated by soil carbon (C/N ~ 16 to 25) mixed with hillslope vegetation (C/N ~ 40+) and diluted by bedrock (Corg = 0.01%, C/N = 4.7). Variations in the vegetation type of the pre-slide hillslopes and the depth of failure (i.e. volume of bedrock) give rise to variability of carbon concentration and source signature between landslides. In river suspended load, Corg ~ 0.5%, C/N ~ 15.6 and δ13C ~ - 23.5‰ at mean flow. These values are relatively uniform along the mountain belt. C_ {org} decreases with increasing suspended sediment concentration. We conclude that the bulk of the suspended

  13. Emission of particulate matter from ternary blends consisting of biodiesel, ethanol and vegetable oil: a comparison with conventional dieselEmissão de material particulado por misturas ternárias compostas de biodiesel, etanol e óleo vegetal: uma comparação com o óleo diesel convencional

    Directory of Open Access Journals (Sweden)

    Murilo Daniel de Melo Innocentini


    Full Text Available The purpose of this study was to quantify the particulate matter emission from ternary blends comprehending biodiesel, ethanol and vegetable oil in a Diesel cycle engine, and an identical engine working with petrol diesel as control. To compare the fuels’ emissions, the particulate matter from the engine’s exhaust was collected, using a fiberglass circular filter paper, which was coupled by means of a steel flange at the end of the exhaust pipe. The results with ternary blends showed expressive reduction of particulate matter level exhausted by the engine, in its maximum load. We can conclude that the utilization of ternary blends, with the methods and conditions of this experiment, was efficient to reduce the emission of particulate matter contained in the exhaust gases of Diesel cycle engine.O objetivo deste trabalho foi quantificar a emissão de material particulado de misturas ternárias compostas de biodiesel, etanol e óleo vegetal em um motor de ciclo Diesel, tendo como testemunha um motor idêntico funcionando com óleo diesel de petróleo. Para a comparação da emissão dos dois combustíveis, foi realizada a coleta de material particulado proveniente dos escapamentos dos motores com um filtro circular confeccionado de fibra de vidro, que foi acoplado com um flange de aço, no final da tubulação de escape. Os resultados obtidos com a utilização das misturas ternárias de biocombustíveis indicaram uma redução expressiva no nível de material particulado emitido pelo motor em sua carga máxima. Pode-se concluir que a utilização das misturas ternárias, nas condições e métodos de realização do experimento, foi eficiente na redução de emissão de material particulado presente nos gases de exaustão do motor de ciclo Diesel.

  14. Stable isotopes of carbon and nitrogen in suspended matter and sediments from the Godavari estuary

    Digital Repository Service at National Institute of Oceanography (India)

    Sarma, V.V.S.S.; Arya, J.; Subbaiah, Ch.V.; Naidu, S.A.; Gawade, L.; PraveenKumar, P.; Reddy, N.P.C.

    of terrigeneous material toward the mouth of the estuary. A significant positive relationship exists between the delta sup(13)C of suspended and sediment, which indicates that these two organic carbon pools are likely coupled in the form of a significant exchange...

  15. Electrically heated particulate filter restart strategy (United States)

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


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

  16. Spacecraft Cabin Particulate Monitor Project (United States)

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

  17. Recent developments in particulate control

    Energy Technology Data Exchange (ETDEWEB)



    Electrostatic precipitators (ESP) are the dominant type of particulate control in pulverised coal combustion (PCC) plant; fabric filters (FF) play a smaller role. Environmental pressures and subsequent tighter regulations have lowered emission limit values (ELV) for particulate matter from PCC plant, and they are now extending to specific toxic metals, such as mercury. Lower ELV are generally met by increasing the efficiency of the existing particulate control via numerous enhancements. However, the existing fleet is ageing, various restrictions on site limit what work can be done and PCC plant is progressively operating under non-design conditions. Despite this, further developments in technology have led to significant improvements in collection efficiency and regulations have been met. New hybrid ESP/FF systems aim to become more viable than the individual technology by utilising the advantages of both technologies. The purpose of this report is to review the technical and economic considerations of enhancements in particulate control for PCC plant over the last decade.

  18. Spacecraft Cabin Particulate Monitor Project (United States)

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

  19. 77 FR 45956 - Approval and Promulgation of Implementation Plans; Kentucky; Louisville; Fine Particulate Matter... (United States)


    ... Particulate Matter 2002 Base Year Emissions Inventory AGENCY: Environmental Protection Agency (EPA). ACTION: Final rule. SUMMARY: EPA is taking final action to approve the 1997 annual fine particulate matter (PM 2... other information whose disclosure is restricted by statute. Certain other material, such as copyrighted...

  20. Spatially Explicit Estimates of Suspended Sediment and Bedload Transport Rates for Western Oregon and Northwestern California (United States)

    O'Connor, J. E.; Wise, D. R.; Mangano, J.; Jones, K.


    Empirical analyses of suspended sediment and bedload transport gives estimates of sediment flux for western Oregon and northwestern California. The estimates of both bedload and suspended load are from regression models relating measured annual sediment yield to geologic, physiographic, and climatic properties of contributing basins. The best models include generalized geology and either slope or precipitation. The best-fit suspended-sediment model is based on basin geology, precipitation, and area of recent wildfire. It explains 65% of the variance for 68 suspended sediment measurement sites within the model area. Predicted suspended sediment yields range from no yield from the High Cascades geologic province to 200 tonnes/ km2-yr in the northern Oregon Coast Range and 1000 tonnes/km2-yr in recently burned areas of the northern Klamath terrain. Bed-material yield is similarly estimated from a regression model based on 22 sites of measured bed-material transport, mostly from reservoir accumulation analyses but also from several bedload measurement programs. The resulting best-fit regression is based on basin slope and the presence/absence of the Klamath geologic terrane. For the Klamath terrane, bed-material yield is twice that of the other geologic provinces. This model explains more than 80% of the variance of the better-quality measurements. Predicted bed-material yields range up to 350 tonnes/ km2-yr in steep areas of the Klamath terrane. Applying these regressions to small individual watersheds (mean size; 66 km2 for bed-material; 3 km2 for suspended sediment) and cumulating totals down the hydrologic network (but also decreasing the bed-material flux by experimentally determined attrition rates) gives spatially explicit estimates of both bed-material and suspended sediment flux. This enables assessment of several management issues, including the effects of dams on bedload transport, instream gravel mining, habitat formation processes, and water-quality. The

  1. Estimating total suspended sediment yield with probability sampling (United States)

    Robert B. Thomas


    The ""Selection At List Time"" (SALT) scheme controls sampling of concentration for estimating total suspended sediment yield. The probability of taking a sample is proportional to its estimated contribution to total suspended sediment discharge. This procedure gives unbiased estimates of total suspended sediment yield and the variance of the...

  2. Optomechanics for thermal characterization of suspended graphene (United States)

    Dolleman, Robin J.; Houri, Samer; Davidovikj, Dejan; Cartamil-Bueno, Santiago J.; Blanter, Yaroslav M.; van der Zant, Herre S. J.; Steeneken, Peter G.


    The thermal response of graphene is expected to be extremely fast due to its low heat capacity and high thermal conductivity. In this work, the thermal response of suspended single-layer graphene membranes is investigated by characterization of their mechanical motion in response to a high-frequency modulated laser. A characteristic delay time τ between the optical intensity and mechanical motion is observed, which is attributed to the time required to raise the temperature of the membrane. We find, however, that the measured time constants are significantly larger than the predicted ones based on values of the specific heat and thermal conductivity. In order to explain the discrepancy between measured and modeled τ , a model is proposed that takes a thermal boundary resistance at the edge of the graphene drum into account. The measurements provide a noninvasive way to characterize thermal properties of suspended atomically thin membranes, providing information that can be hard to obtain by other means.

  3. Reduction of gaseous pollutants and particulate materials by using fuels derived from vegetable in substitution to diesel oil; Reducao de poluentes gasosos e de material particulado por meio do uso de combustiveis a base de oleos vegetais como substitutos ao oleo diesel

    Energy Technology Data Exchange (ETDEWEB)

    Yazaki, Carlos Kazuaki [General Motors do Brasil, Sao Caetano do Sul, SP (Brazil). Engenharia de Chassis e Integracao Powertrain]. E-mail:; Trielli, Mauricio Assumpcao [Sao Paulo Univ., SP (Brazil). Escola Politecnica. Dept. de Engenharia Mecanica]. E-mail:


    The aim of this article is to present the contribution allowed by fuels derived from vegetable oils in substitution for the diesel oil. It especially emphasizes the vegetable oil esters potential as gaseous exhaust pollutant and particulate matter reduction produced by ignition compression engines, such a conclusion has been achieved through systematization and analysis of results of experimental tests performed by several researchers that applied natural vegetable oils and their esters to this class of engines. Once the vegetable oils are the base of formation of these fuels, their direct application in these engines is also analyzed showing the advantages and disadvantages of this alternative route. This article also includes an analysis of their physical and chemical properties which help the understanding of their performance in the engines. Due to better results obtained from esters use, their industrial processing, the special characteristics of the engineering materials which they will have contact in engine, principally those used in injection systems, as well as aspects related to their storages are discussed too. (author)

  4. Suspended matter and fluid mud off Alleppey, southwest coast of India (United States)

    Shynu, R.; Rao, V. Purnachandra; Samiksha, S. V.; Vethamony, P.; Naqvi, S. W. A.; Kessarkar, Pratima M.; Babu, M. T.; Dineshkumar, P. K.


    Time series measurements on suspended particulate matter (SPM) were made at one non-mud bank (M1) and two mud bank stations (M2 and M3) off Alleppey, south west coast of India. The mean SPM was low in surface (6.2 mg/l) and mid-depth (3.7 mg/l) waters and higher in bottom-depth waters (24.6 mg/l) of these stations, during both pre-monsoon and monsoon seasons. Near bed suspended sediment results indicated low SPM during July (0.042 g/l) and September (0.018 g/l) at M1, but very high SPM at M2 (9.2 g/l) and M3 (6.2 g/l) during July that decreased (M2: 0.033 g/l; M3: 0.1 g/l) again in September. Observations based on LISST-25X indicated that optical transmission (OT) was high (80-100%) in surface and mid-depth waters but decreased with increasing depth. Near bed waters at M2 and M3 stations showed ∼1 m thick fluid layer with 0% OT and with high particle volume concentrations (150-200 μl/l) during monsoon. Bottom sediments were clayey silts. Sediments of fluid mud close to the bottom at M2 and M3 stations. As the wave height decreased from ∼3 m in May to 0.76 m in July, the dissipated wave energy probably liquefied, eroded and re-suspended the bottom sediment to form fluid mud. Upwelling currents may have been involved in the up keep and transportation of fluid mud. The suspended mud resettled at the bottom soon after the monsoon event.

  5. Seasonal sedimentation of autochthonous material from the euphotic zone of a coastal system (United States)

    Olesen, Michael; Lundsgaard, Claus


    The seasonal sedimentation of particulate matter across the pycnocline was recorded in the Kattegat during the period of stratification (March-October 1989). The proportion of viable phytoplankton cells of the total carbon flux (63 g C m -2) was low (18%). Faecal pellets contributed on average less than 5%. The major component of the sinking matter consisted of detrital material (amorphous particles with few recognizable components) which was estimated mainly to originate from the activity of microzooplankton. The average C/N ratio of the particulate biogenic matter trapped at the pycnocline was 8·6, but only 6·4 for the suspended particulate organic matter in the mixed layer indicating that nitrogen is more effectively recycled than carbon in the euphotic zone. This mechanism allows for an additional new organic carbon production of 33% compared to that which can be estimated from the external loading of nitrogen. Over the entire period the average daily vertical flux of carbon corresponded to 14% of the phytoplankton biomass indicating a high efficiency in the transport of organic material from the euphotic zone to the bottom.

  6. IUTAM symposium on hydrodynamic diffusion of suspended particles

    Energy Technology Data Exchange (ETDEWEB)

    Davis, R.H. [ed.


    Hydrodynamic diffusion refers to the fluctuating motion of nonBrownian particles (or droplets or bubbles) which occurs in a dispersion due to multiparticle interactions. For example, in a concentrated sheared suspension, particles do not move along streamlines but instead exhibit fluctuating motions as they tumble around each other. This leads to a net migration of particles down gradients in particle concentration and in shear rate, due to the higher frequency of encounters of a test particle with other particles on the side of the test particle which has higher concentration or shear rate. As another example, suspended particles subject to sedimentation, centrifugation, or fluidization, do not generally move relative to the fluid with a constant velocity, but instead experience diffusion-like fluctuations in velocity due to interactions with neighboring particles and the resulting variation in the microstructure or configuration of the suspended particles. In flowing granular materials, the particles interact through direct collisions or contacts (rather than through the surrounding fluid); these collisions also cause the particles to undergo fluctuating motions characteristic of diffusion processes. Selected papers are indexed separately for inclusion in the Energy Science and Technology Database.

  7. Self-suspended permanent magnetic FePt ferrofluids

    KAUST Repository

    Dallas, Panagiotis


    We present the synthesis and characterization of a new class of self-suspended ferrofluids that exhibit remanent magnetization at room temperature. Our system relies on the chemisorption of a thiol-terminated ionic liquid with very low melting point 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 component. The ferrofluids do not show any sign of flocculation or phase separation, despite the strong interactions between the magnetic nanoparticles due to the strong chemisorption of the ionic liquid as evidenced by Raman spectroscopy and thermal analysis. Composites with high FePt loading (40 and 70. wt%) exhibit a pseudo solid-like rheological behavior and high remanent magnetization values (10.1 and 12.8. emu/g respectively). At lower FePt loading (12. wt%) a liquid like behavior is observed and the remanent and saturation magnetization values are 3.5 and 6.2. emu/g, respectively. The magnetic and flow properties of the materials can be easily fine tuned by controlling the type and amount of FePt nanoparticles used. © 2013 Elsevier Inc.

  8. Influence of particulates on phosphorus loading exported from farm drainage during a storm event in the Everglades Agricultural Area (United States)

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


    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.

  9. Electrical diesel particulate filter (DPF) regeneration (United States)

    Gonze, Eugene V; Ament, Frank


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

  10. Sedimentation of suspended solids in ultrasound field

    Directory of Open Access Journals (Sweden)

    Vikulina Vera


    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.

  11. Suspended sediments limit coral sperm availability (United States)

    Ricardo, Gerard F.; Jones, Ross J.; Clode, Peta L.; Humanes, Adriana; Negri, Andrew P.


    Suspended sediment from dredging activities and natural resuspension events represent a risk to the reproductive processes of coral, and therefore the ongoing maintenance of reefal populations. To investigate the underlying mechanisms that could reduce the fertilisation success in turbid water, we conducted several experiments exposing gametes of the corals Acropora tenuis and A. millepora to two sediment types. Sperm limitation was identified in the presence of siliciclastic sediment (230 and ~700 mg L−1), with 2–37 fold more sperm required to achieve maximum fertilisation rates, when compared with sediment-free treatments. This effect was more pronounced at sub-optimum sperm concentrations. Considerable (>45%) decreases in sperm concentration at the water’s surface was recorded in the presence of siliciclastic sediment and a >20% decrease for carbonate sediment. Electron microscopy then confirmed sediment entangled sperm and we propose entrapment and sinking is the primary mechanism reducing sperm available to the egg. Longer exposure to suspended sediments and gamete aging further decreased fertilisation success when compared with a shorter exposure. Collectively, these findings demonstrate that high concentrations of suspended sediments effectively remove sperm from the water’s surface during coral spawning events, reducing the window for fertilisation with potential subsequent flow-on effects for recruitment. PMID:26659008

  12. Ecological effect of airborne particulate matter on plants

    Directory of Open Access Journals (Sweden)

    Santosh Kumar Prajapati


    Full Text Available Atmospheric particulate matter is a mixture of diverse elements. Deposition of particulate matter to vegetated surfaces depends on the size distribution of these particles and, to a lesser extent, on the chemistry. Effects of particulate matter on vegetation may be associated with the reduction in light required for photosynthesis and an increase in leaf temperature due to changed surface optical properties. Changes in energy exchange are more important than the diffusion of gases into and out of leaves which is influenced by dust load, color and particle size. Alkaline dust materials may cause leaf surface injury while other materials may be taken up across the cuticle. A more probable route for metabolic uptake and impact on vegetation and ecosystems is through the rhizosphere. Interception of dusts by vegetation makes an important contribution to the improvement of air quality in the vicinity of vegetation. Although the effect of particulate matter on ecosystem is linked to climate change, there is little threat due to un-speciated particulate matter on a regional scale.

  13. Determination of Vanadium, Tin and Mercury in Atmospheric Particulate Matter and Cement Dust Samples by Direct Current Plasma Atomic Emission Spectrometry. (United States)

    Hindy, Kamal T.; And Others


    An atmospheric pollution study applies direct current plasma atomic emission spectrometry (DCP-AES) to samples of total suspended particulate matter collected in two industrial areas and one residential area, and cement dust collected near major cement factories. These samples were analyzed for vanadium, tin, and mercury. The results indicate the…

  14. Carbon sources in suspended particles and surface sediments from the Beaufort Sea revealed by molecular lipid biomarkers and compound-specific isotope analysis


    I. Tolosa; S. Fiorini; B. Gasser; J. Martín; J. C. Miquel


    Molecular lipid biomarkers (hydrocarbons, alcohols, sterols and fatty acids) and compound-specific isotope analysis of suspended particulate organic matter (SPM) and surface sediments of the Mackenzie Shelf and slope (southeast Beaufort Sea, Arctic Ocean) were studied in summer 2009. The concentrations of the molecular lipid markers, characteristic of known organic matter sources, were grouped and used as proxies to evaluate the relative importance of fresh algal, detrital a...


    Directory of Open Access Journals (Sweden)

    Aries Dwi Siswanto


    Full Text Available Sebaran sedimen tersuspensi (Total Suspended Solid (TSS dapat dipelajari secara horizontal maupun vertikal. Akumulasi sedimen tersuspensi (TSS secara horizontal sangat dipengaruhi oleh arus permukaan maupun gelombang yang dibangkitkan oleh angin. Keterdapatan TSS ini diduga berpengaruh terhadap sebarannya pada profil vertical. Kedua kondisi sebaran sedimen tersuspensi (TSS berpengaruh terhadap optimalisasi penetrasi cahaya matahari di perairan. Sedimen tersuspensi (TSS menjadi salah satu factor fisika yang penting sebagai indicator kondisi perairan. Penelitian ini bertujuan untuk mengetahui sebaran Total Suspended Solid (TSS di perairan Kabupaten Bangkalan. Materi utama yang digunakan dalam penelitian ini adalah contoh air dan data parameter lingkungan (pasang surut dan kecerahan yang diambil pada 7 stasiun pada bulan Agustus-September 2013 di Perairan Selat Madura, Kabupaten Bangkalan. Metode gravimetric (SNI-06-6989.3-2004 digunakan untuk analisa Total Suspended Solid (TSS. Data parameter lingkungan dianalisa secara deskriptif. Analisa TSS menunjukkan nilai yang berbeda pada beberapa stasiun penelitian untuk setiap minggunya. Konsentrasi TSS terendah sebesar 35 mg/L (Stasiun 3, profil permukaan, minggu pertama dan tertinggi sebesar 620 mg/L (Stasiun 4, profil dasar, minggu pertama. Secara umum, konsentrasi TSS secara vertikal (dari permukaan-dasar cenderung semakin besar, diduga dipengaruhi oleh jenis substrat dan parameter arus yang berpeluang untuk menimbulkan pengadukan di profil dasar. Kondisi lingkungan (kecerahan dan arus menunjukkan bahwa daerah dengan konsentrasi TSS yang tinggi cenderung memilki nilai kecerahan yang rendah dengan kecepatan arus yang lebih besar.Kata Kunci: kecerahan, pola arus, Total Suspended Solid (TSS DISTRIBUTION OF TOTAL SUSPENDED SOLID (TSS IN THE VERTICAL PROFILE IN THE MADURA STRAIT WATERS BANGKALAN DISTRICTABSTRACTDistribution of suspended sediment (Total Suspended Solid (TSS can be studied through

  16. Study of the heavy metals speciation in the atmospheric suspended particles in Sevilla (Spain); Estudio de la especiacion de metales pesados en la materia particulada atmosferica de la ciudad de Sevilla

    Energy Technology Data Exchange (ETDEWEB)

    Ternero Rodriguez, M.; Sequeiros Madueno, L.; Jimenez Sanchez, C.; Barragan de la Rosa, J.; Bello Lopez, M.; Fernandez Espinosa, A.J.; Perez Bernal, J.L. [Facultad de Quimica, Universidad de Sevilla (Spain)


    This work develops analytical methods for the heavy metals speciation in the atmospheric suspended particles. In base to these methods, we study the atmospheric contamination of the city of Seville, determining the metals Al, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Cd and Pb. We also study the effects of metallic species in the alteration processes on rocks material, in base to the SO{sub 2}/SO{sub 4}{sup {minus}{minus}}. The project develops in two years: in the first, we develop the methods of chemistry speciation based on the extraction with different reagents and the methods of physical speciation based on the particle size distribution with cascade impactors. Also, we develop the methodology for the environmental simulation of alteration processes, in base to the heterogeneous catalysis, by metallic ions, of the SO{sub 2} on the surface of the stone. In the second year we apply the methods of speciation to the study of the contamination by heavy metals in the city of Seville. This part divides in two phases: a first of the preliminary study in the city in order to identify the different polluting focuses, and a secondary of study of the contamination produced by punctual sources, in the more polluted points of the city. On the other hand, the study of the alteration processes of rock materials has centred on materials employees in monuments of the city and on application of the catalyzers found in the particulate matter of the true environment of the materials. (Author)

  17. Multi-faceted monitoring of estuarine turbidity and particulate matter provenance: Case study from Salem Harbor, USA. (United States)

    Hubeny, J Bradford; Kenney, Melanie; Warren, Barbara; Louisos, Jeremy


    Turbidity is a water quality parameter that is known to adversely affect aquatic systems, however the causes of turbid water are often elusive. We present results of a study designed to constrain the source of particulate matter in a coastal embayment that has suffered from increased turbidity over past decades. Our approach utilized monitoring buoys to quantify turbidity at high temporal resolution complemented by geochemical isotope analysis of suspended sediment samples and meteorological data. Results reveal a complex system in which multiple sources are associated with particulate matter. Weight of evidence demonstrates that phytoplankton productivity in the water column, however, is the dominant source of particulate matter associated with elevated turbidity in Salem Harbor, Massachusetts. Allochthonous matter from the watershed was observed to mix into the pool of suspended particulate matter near river mouths, especially in spring and summer. Resuspension of harbor surface sediments likely provides additional particulates in the regions of boat moorings, especially during summer when recreational boats are attached to moorings. Our approach allows us to constrain the causes of turbidity events in this embayment, is helping with conservation efforts of environmental quality in the region, and can be used as a template for other locations. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. Minimum gas speed in heat exchangers to avoid particulate fouling

    NARCIS (Netherlands)

    Abd-Elhady, M.S.; Rindt, C.C.M.; Wijers, J.G.; van Steenhoven, A.A.; Bramer, Eduard A.; van der Meer, Theodorus H.


    The minimum gas speed for a heat exchanger (HE) at which particulate fouling is avoided is investigated. Fouling experiments have been done with particles of different sizes and different materials running under different gas speeds. It is found that the smallest particles in the flow deposit first

  19. Particulate Matter and Noise Impact Studies of Waste Rock Dump ...

    African Journals Online (AJOL)

    Adansi Gold Company Limited identified an economically viable gold deposit at Nkran in the Amansie West District of Ghana. Mining of this deposit requires the disposal of waste rock materials at a proposed waste rock dump near Nkran and Koninase communities. Since particulates and noise emissions from the ...

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

    Umaiyakunjaram, R; Shanmugam, P


    This study deals with the treatment of high suspended solids raw tannery wastewater using flat sheet Submerged Anaerobic Membrane (0.4μm) Bioreactor (SAMBR) acclimatized with hypersaline anaerobic seed sludge for recovering biogas. The treatability of SAMBR achieved higher CODremoval efficiency (90%) and biogas yield (0.160L.g(-1) CODremoved) coincided with high r(2) values between permeate flux and TSS (0.95), biogas and COD removed (0.96). The acidification of hypersaline influent wastewater by biogas mixing with high CO2, achieved quadruplet benefit of gas liquid and solid separation, in-situ pH and NH3 control, in-situ CH4 enrichment, and prevention of membrane fouling. The initial high VFA became stable as time elapsed reveals the hydrolysing ability of particulate COD into soluble COD and into biogas, confirms the suitability of SAMBR for high suspended solids tannery wastewater. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Hydrocarbon-enhanced particulate filter regeneration via microwave ignition (United States)

    Gonze, Eugene V.; Brown, David B.


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

  2. Particulate organic matter in rivers of Fukushima: An unexpected carrier phase for radiocesiums. (United States)

    Naulier, Maud; Eyrolle-Boyer, Frédérique; Boyer, Patrick; Métivier, Jean-Michel; Onda, Yuichi


    The role of particulate organic matter in radiocesium transfers from soils to rivers was investigated in areas contaminated by the Fukushima Daiichi Nuclear Power Plant accident. Suspended and deposited sediments, filtered water, macro organic debris and dead leaves were sampled along the six most contaminated coastal river catchments of the Fukushima prefecture in the early autumns 2013 and 2014. Radiocesium concentrations of river samples and total organic carbon concentrations in suspended and deposited sediments were measured. Radiocesium concentrations of suspended and deposited sediments were significantly correlated to 137Cs inventories in soils and total organic carbon. The distributions of radiocesium between the organic and mineral phases of both types of sediment were assessed by using a modelling approach. The results suggest that, during the early autumn season, the organic fraction was the main phase that carried the radiocesiums in deposited sediments and in suspended sediments for suspended loads Fukushima could be attributed to the high radiocesium contents of particulate organic matter. Since it is well known that organic compounds generally do not significantly adsorb radiocesium onto specific sites, several hypotheses are suggested: 1) Radiocesiums may have been absorbed into organic components at the early stage of atmospheric radioactive deposits and/or later due to biomass recycling and 2) Those elements would be partly carried by glassy hot particles together with organic matter transported by rivers in Fukushima. Both hypotheses would lead to conserve the amount of radiocesiums associated with particles during their transfers from the contaminated areas to the marine environment. Finally, such organically bound radiocesium would lead to significant deliveries of bioavailable radiocesium for living organisms at Fukushima. Copyright © 2016 Elsevier B.V. All rights reserved.

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

    DEFF Research Database (Denmark)

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


    This study investigated the hypotheses that humans are affected by air pollution caused by ozone and house dust, that the effect of simultaneous exposure to ozone and dust in the air is larger than the effect of these two pollutants individually, and that the effects can be measured as release...... of cytokines and changes of the respiratory function. Experimental exposures of eight atopic but otherwise healthy subjects were performed in a climate chamber under controlled conditions. The three controlled exposures were about 75 microg/m3 total suspended particulate matter, 0.3 p.p.m. ozone......, and the combination of these. The exposure duration was 3 h. The outcome measures were interleukins and cells in nasal lavages (NAL), respiratory function, bronchial metacholine responsiveness, rhinometry symptoms and general well-being in a questionnaire and time course of general irritation on a visual analogue...

  4. Temporal and spatial variability of trace metals in suspended matter of the Mandovi estuary, central west coast of India

    Digital Repository Service at National Institute of Oceanography (India)

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

    of the suspended particulate matter (SPM) in estuaries are controlled by seasonal changes in inputs from river-end and marine-end members, physico-chemical processes occurring at the mixing zone of freshwater and salt water and biological productivity (Boyden et... al. 1979; Kennedy 1984; Balls 1990; Turner et al. 1991; Burton et al. 1994; Balls et al. 1997; Paucot and Wollast 1997; Zwolsman and van Eck 1999; Nolting et al. 1999; Hatje et al. 2001; Qiao et al. 2007; Kessarkar et al. 2009). Flocculation...

  5. Monitoring of suspended sediment in South Tyrol (United States)

    Nadalet, Rudi; Dinale, Roberto; Pernter, Martin; Maraldo, Luca; Peterlin, Dieter; Richter, Arnold; Comiti, Francesco


    In the context of the EU Water Framework Directive (WFD), which aims to achieve a good status of European water bodies, the Hydrographic Office of the Autonomous Province of Bolzano (Italy) extended in 2014 its institutional activities including the monitoring of suspended sediment in the river channel network. Currently, the only active monitoring station is on the Adige River at the gauging station of Ponte Adige near Bolzano (drainage area 2705 km2). The applied monitoring strategy and the data analysis concept are both based on the guidelines issued by the Austrian Federal Ministry of Agriculture, Forestry, Environment and Water Management (BMLFUW). The results indicates that the temporal variability strongly differs during the investigated period (2014-2015). In addition to the analysis of precipitation and water discharge, temperature and lightning activity were also included to better understand the sediment transport dynamics observed at the station. In summer 2015, the combination of constantly high daily temperature throughout the Adige basin (which drove intense glacier melting in the headwaters) with a high frequency of convective rainfall events (90% more than in 2014, obtained through lightning detection), led to an annual mass of transported suspended sediment of 260000 t. Interestingly, this value is similar to the one estimated for 2014 (300000 t), which was characterized by very different meteorological conditions (colder and wetter summer), but with the occurrence of an important flood in August, which transported half of the annual amount. Finally, we can conclude that the adopted monitoring strategy is applicable for institutional aims in terms of costs as well as in terms of time effort. During the next years, other stations for suspended sediment monitoring are planned to be installed in the Province to cover the most important river segments.

  6. Chemical-morphological analysis and evaluation of the distribution of particulate matter in the Toluca Valley; Analisis quimico-mofologico y evaluacion de la distribucion de materia particulada en el Valle de Toluca

    Energy Technology Data Exchange (ETDEWEB)

    Romero G, E.T.; Sandoval P, A.; Morelos M, J. [ININ, 52750 La Marquesa, Estado de Mexico (Mexico); Reyes G, L.R. [UAEH, 42184 Pachuca, Hidalgo (Mexico)]. e-mail:


    The breathable fraction of the suspended particles is the main pollutant in the Metropolitan Area of the Toluca Valley (ZMVT), to have the bigger number of days outside of standard, especially during the winter and low water time, its registered maximum value is of 367 IMECA points in 2004. The particles present a potential risk for the lungs, its increase the chemical reactions in the atmosphere; its reduce the visibility; its increase the possibility of the precipitation, the fog and the clouds; its reduce the solar radiation, with the changes in the environmental temperature and in the biological growth rates of those plants; and it dirties the soil matters. For that reason it is very important to characterize physicochemical and morphologically by scanning electron microscopy the particulate material of the Toluca Valley, to determine to that type of particles is potentially exposed the population before drastic scenarios of air pollution of the Toluca Valley, as well as to evaluate the distribution of the one particulate material in the ZMVT. (Author)

  7. Active noise cancellation in a suspended interferometer

    CERN Document Server

    Driggers, Jennifer C; Pepper, Keenan; Adhikari, Rana


    We demonstrate feed-forward vibration isolation on a suspended Fabry-Perot interferometer using Wiener filtering and a variant of the common Least Mean Square (LMS) adaptive filter algorithm. We compare the experimental results with theoretical estimates of the cancellation efficiency. Using data from the recent LIGO Science Run, we also estimate the impact of this technique on full scale gravitational wave interferometers. In the future, we expect to use this technique to also remove acoustic, magnetic, and gravitational noise perturbations from the LIGO interferometers. This noise cancellation technique is simple enough to implement in standard laboratory environments and can be used to improve SNR for a variety of high precision experiments.

  8. Geodetic monitoring of suspended particles in rivers (United States)

    Kamnik, Rok; Maksimova, Daria; Kovačič, Boštjan


    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.

  9. Safety Harness For Work Under Suspended Load (United States)

    Sunoo, Su Young


    Safety device protects worker under suspended engine or other heavy load. Mechanically linked with load so if load should fall, worker yanked safely away. Worker wears chest-plate vest with straps crossing eye on back. Lower safety cable connected to eye extends horizontally away from worker to nearby wall, wrapped on pulley and extends upward to motion amplifier or reducer. Safety cables transform any sudden downward motion of overhanging load into rapid sideways motion of worker. Net catches worker, preventing worker from bumping against wall.

  10. Repair of tegmen defect using cranial particulate bone graft. (United States)

    Greene, Arin K; Poe, Dennis S


    Bone paté is used to repair cranial bone defects. This material contains bone-dust collected during the high-speed burring of the cranium. Clinical and experimental studies of bone dust, however, have shown that it does not have biological activity and is resorbed. We describe the use of bone paté using particulate bone graft. Particulate graft is harvested with a hand-driven brace and 16mm bit; it is not subjected to thermal injury and its large size resists resorption. Bone paté containing particulate graft is much more likely than bone dust to contain viable osteoblasts capable of producing new bone. Copyright © 2015 Elsevier Inc. All rights reserved.

  11. Evaluation of dredged material proposed for ocean disposal from Shark River Project area

    Energy Technology Data Exchange (ETDEWEB)

    Antrim, L.D.; Gardiner, W.W.; Barrows, E.S.; Borde, A.B. [Battelle/Marine Sciences Lab., Sequim, WA (United States)


    The objective of the Shark River Project was to evaluate proposed dredged material to determine its suitability for unconfined ocean disposal at the Mud Dump Site. Tests and analyses were conducted on the Shark River sediments. The evaluation of proposed dredged material consisted of bulk sediment chemical and physical analysis, chemical analyses of dredging site water and elutriate, water-column and benthic acute toxicity tests, and bioaccumulation tests. Individual sediment core samples collected from the Shark River were analyzed for grain size, moisture content, and total organic carbon (TOC). One sediment composite was analyzed for bulk density, specific gravity, metals, chlorinated pesticides, polychlorinated biphenyl (PCB) congeners, polynuclear aromatic hydrocarbons (PAHs), and 1,4- dichlorobenzene. Dredging site water and elutriate, prepared from suspended-particulate phase (SPP) of the Shark River sediment composite, were analyzed for metals, pesticides, and PCBs. Benthic acute toxicity tests and bioaccumulation tests were performed.

  12. Polishing of POME by Chlorella sp. in suspended and immobilized system (United States)

    Lahin, F. A.; Sarbatly, R.; Suali, E.


    The effect of using suspended and immobilized growth of Chlorella sp. to treat POME was studied. Cotton and nylon ropes were used as the immobilization material in a rotating microalgae biofilm reactor. The result showed that POME treated in suspended growth system was able to remove 81.9% and 55.5% of the total nitrogen (TN) and total phosphorus (TP) respectively. Whereas the immobilized system showed lower removal of 77.22% and 53.02% for TN and TP. Lower performance of immobilized microalgae is due to the limited light penetration and supply of CO2 inside the immobilization materials. The rotating microalgae biofilm reactor was able to reduce the biochemical oxygen demand (BOD) to 90 mg/L and chemical oxygen demand (COD) to 720 mg/L. Higher BOD and COD reading were obtained in suspended growth due to the presence of small number of microalgae cell in the samples. This study shows that suspended growth system is able to remove higher percentages of nitrogen and phosphorus. However, an efficient separation method such as membrane filtration is required to harvest the cultivated microalgae cell to avoid organic matter release into water bodies.

  13. Length-dependent thermal conductivity in suspended single-layer graphene. (United States)

    Xu, Xiangfan; Pereira, Luiz F C; Wang, Yu; Wu, Jing; Zhang, Kaiwen; Zhao, Xiangming; Bae, Sukang; Tinh Bui, Cong; Xie, Rongguo; Thong, John T L; Hong, Byung Hee; Loh, Kian Ping; Donadio, Davide; Li, Baowen; Özyilmaz, Barbaros


    Graphene exhibits extraordinary electronic and mechanical properties, and extremely high thermal conductivity. Being a very stable atomically thick membrane that can be suspended between two leads, graphene provides a perfect test platform for studying thermal conductivity in two-dimensional systems, which is of primary importance for phonon transport in low-dimensional materials. Here we report experimental measurements and non-equilibrium molecular dynamics simulations of thermal conduction in suspended single-layer graphene as a function of both temperature and sample length. Interestingly and in contrast to bulk materials, at 300 K, thermal conductivity keeps increasing and remains logarithmically divergent with sample length even for sample lengths much larger than the average phonon mean free path. This result is a consequence of the two-dimensional nature of phonons in graphene, and provides fundamental understanding of thermal transport in two-dimensional materials.

  14. A Seasonally Robust Empirical Algorithm to Retrieve Suspended Sediment Concentrations in the Scheldt River

    Directory of Open Access Journals (Sweden)

    Dries Raymaekers


    Full Text Available A seasonally robust algorithm for the retrieval of Suspended Particulate Matter (SPM in the Scheldt River from hyperspectral images is presented. This algorithm can be applied without the need to simultaneously acquire samples (from vessels and pontoons. Especially in dynamic environments such as estuaries, this leads to a large reduction of costs, both in equipment and personnel. The algorithm was established empirically using in situ data of the water-leaving reflectance obtained over the tidal cycle during different seasons and different years. Different bands and band combinations were tested. Strong correlations were obtained for exponential relationships between band ratios and SPM concentration. The best performing relationships are validated using airborne hyperspectral data acquired in June 2005 and October 2007 at different moments in the tidal cycle. A band ratio algorithm (710 nm/596 nm was successfully applied to a hyperspectral AHS image of the Scheldt River to obtain an SPM concentration map.

  15. Heavy metal content of total suspended air particles in the heavily industrialized town of Gebze, Turkey. (United States)

    Ergenekon, Pinar; Ulutaş, Kadir


    Air pollution is a serious environmental problem in industrialized towns, where a significant portion of the residents live in close proximity to factories and major highways with high traffic load. In this study, the ambient air quality in Gebze, an industrial region with an area of 438 km(2) and a population of 300,000, was characterized in terms for total suspended particulate matter and its composition of trace elements, i.e. Cd, Cr, Cu, Fe, Mn, Ni and Pb. Samples were collected using high volume samplers from March to June 2009 at two sites during the day and the night. A significantly higher Cu concentrations during night suggested that Cu emissions were the result of a local source. The known air toxics, Cd and Ni, had average concentrations (34 and 43 ng/m(3), respectively) higher than proposed by the European Union's ambient air quality standards. These results highlight the potential health risks for the local population.

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

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


    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.

  17. Method for forming suspended micromechanical structures (United States)

    Fleming, James G.


    A micromachining method is disclosed for forming a suspended micromechanical structure from {111} crystalline silicon. The micromachining method is based on the use of anisotropic dry etching to define lateral features of the structure which are etched down into a {111}-silicon substrate to a first etch depth, thereby forming sidewalls of the structure. The sidewalls are then coated with a protection layer, and the substrate is dry etched to a second etch depth to define a spacing of the structure from the substrate. A selective anisotropic wet etchant (e.g. KOH, EDP, TMAH, NaOH or CsOH) is used to laterally undercut the structure between the first and second etch depths, thereby forming a substantially planar lower surface of the structure along a {111} crystal plane that is parallel to an upper surface of the structure. The lateral extent of undercutting by the wet etchant is controlled and effectively terminated by either timing the etching, by the location of angled {111}-silicon planes or by the locations of preformed etch-stops. This present method allows the formation of suspended micromechanical structures having large vertical dimensions and large masses while allowing for detailed lateral features which can be provided by dry etch definition. Additionally, the method of the present invention is compatible with the formation of electronic circuitry on the substrate.

  18. Distribution of some chemical elements between dissolved and particulate phases in the ocean. Research period: August 1, 1975--July 31, 1976. [Fallout /sup 210/Po and /sup 210/Pb diffusion in oceans

    Energy Technology Data Exchange (ETDEWEB)


    Progress is reported on studies on the distributions of fallout /sup 210/Pb and /sup 210/Po in dissolved and particulate states in the Gulf of Maine and a transect of the equatorial North Atlantic Ocean. The ratio of /sup 210/Pb//sup 226/Ra and /sup 210/Po//sup 210/Pb in seawater and suspended particulate matter in samples collected from 10 stations in the tropical and eastern North Atlantic and two stations in the Pacific was also determined. (CH)

  19. Intergrating cavity absorption meter measurements of dissolved substances and suspended particles in ocean water (United States)

    Pope, Robin M.; Weidemann, Alan D.; Fry, Edward S.


    We have developed a new device to measure the separate contributions to the spectral absorption coefficient due to a pure liquid, due to the particles suspended in it, and due to the substances dissolved in it. This device, the Integrating Cavity Absorption Meter (ICAM), is essentially independent of scattering effects in the sample. In April 1993, a prototype of the ICAM was field tested on board the research vessel USNS Bartlett. A major part of the cruise track included criss-crossing the area where the Mississippi flows into the Gulf of Mexico at various ranges from the mouth of the river; thus samples were collected from areas of blue, green, and brown/black water. We evaluated 35 seawater samples collected with 5-l Niskin bottles from 22 locations to determine absorption spectra (380-700 nm) of suspended particles and dissolved substances (gelbstoff). Results validate the ICAM as a viable tool for marine optical absorption research. Gelbstoff absorption at 432.5 nm ranged from 0.024 to 0.603 m -1. Over the spectral region 380→560 nm, gelbstoff absorption by each of the samples could be accurately fit to a decaying exponential. The particle absorption spectra are generally characteristic of those of phytoplankton and exhibit a local maximum at 430-440 nm. Absorption values at 432.5 nm ranged from ˜zero to ˜1.0 m -1. Some samples with moderate particulate absorption, however, did not show the characteristic local maximum of phytoplankton in the blue and instead resembled the characteristic decaying exponential of detritus with a shape similar to that observed in the gelbstoff. The ratio of gelbstoff to particulate absorption at 432.5 nm ranged from 0.46 to 152.

  20. CDC WONDER: Daily Fine Particulate Matter (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...

  1. Depth-integrated suspended sediment and geochemical fluxes in large rivers: the Amazon River system (United States)

    Bouchez, J.; Lupker, M.; Gaillardet, J.; Metivier, F.; France-Lanord, C.; Maurice, L.


    Erosion and weathering produce a wide range of residual solid products, in terms of size, density, mineralogy and chemical composition. These solid products are then transported by rivers from the continents to the oceans as suspended particulate matter (SPM) and bedload. Large rivers account for an important part of this transfer of sediments at the global scale. In those rivers, deep channels allow for vertical differentiation, or sorting, of suspended sediment, following their size and density. This hydrodynamic sorting results in vertically heterogeneous depth-profiles in terms of SPM concentration and size distribution (e.g. Garcia, 2008), which in turn likely result in an heterogeneous chemical composition of SPM throughout channel depth (e.g. Galy, 2007), which has to be evaluated. We sampled river water of the main tributaries of the Amazon River system (in the lowland basin), at two distinct water-stages, at various depths following depth-profiles, using a point depth-sampler. After filtration, and SPM recovery, SPM concentration, grain size distribution and chemical composition were determined. River discharge and water velocity throughout the sampled cross-sections were recorded using Acoustic Doppler Current Profiler (ADCP). The large increase in SPM concentration with depth observed at most of the sampled depth-profiles is well accounted for by the Rouse model (e.g. Rouse, 1950). This analysis allows us to reliably infer the SPM concentration and grain size distribution throughout the sampled river cross-section, and thus to estimate the spatially-integrated instantaneous SPM flux using ADCP data (Bouchez et al., 2010). The study also emphasizes the potential role of particle aggregation, within the river system, as a complicating factor regarding the prediction of these depth-integrated SPM fluxes from easily measurable hydrodynamic parameters (surface SPM concentration and grain size, and water velocity). Then, using the previous analysis, combined

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

    Directory of Open Access Journals (Sweden)

    Zhang Wei


    Full Text Available To develop urban stormwater management effectively, characterization of urban runoff pollution between dissolved and particulate phases was studied by 12 rainfall events monitored for five typical urban catchments. The average event mean concentration (AEMC of runoff pollutants in different phases was evaluated. The AEMC values of runoff pollutants in different phases from urban roads were higher than the ones from urban roofs. The proportions of total dissolved solids, total dissolved nitrogen, and total dissolved phosphorus in total ones for all the catchments were 26.19%–30.91%, 83.29%–90.51%, and 61.54–68.09%, respectively. During rainfall events, the pollutant concentration at the initial stage of rainfall was high and then sharply decreased to a low value. Affected by catchments characterization and rainfall distribution, the highest concentration of road pollutants might appear in the later period of rainfall. Strong correlations were also found among runoffs pollutants in different phases. Total suspended solid could be considered as a surrogate for particulate matters in both road and roof runoff, while dissolved chemical oxygen demand could be regarded as a surrogate for dissolved matters in roof runoff.

  3. Environmentally-suspended sediment production of the Nasia River ...

    African Journals Online (AJOL)

    The study assessed the level of suspended sediment produced in the Nasia River Basin. Hydrological and meteorological data and water samples were used for the study. Average suspended sediment yield (33 years) in the basin was 19.90 t/km2/yr. With mean annual runoff of 439.13m3/s, 322.43 t/yr suspended sediment ...

  4. Particulate matter and preterm birth (United States)

    Particulate matter (PM) has been variably associated with preterm birth (PTB) (gestation <37 weeks), but the role played by specific chemical components of PM has been little studied. We examined the association between ambient PM <2.5 micrometers in aerodynamic diameter (PM2.S) ...

  5. Transport phenomena in particulate systems

    CERN Document Server

    Freire, José Teixeira; Ferreira, Maria do Carmo


    This volume spans 10 chapters covering different aspects of transport phenomena including fixed and fluidized systems, spouted beds, electrochemical and wastewater treatment reactors. This e-book will be valuable for students, engineers and researchers aiming to keep updated on the latest developments on particulate systems.

  6. 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


    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


    African Journals Online (AJOL)

    Elemental concentrations of airborne particulate matter 9 sampled at three urban site classes m Lagos (an industrial city) 1n southWest Nigeria were subjected to statistical -' analysis to determine the number and nature of sources impacting the receptor sites. Inter-elemental Correlation, , '. Principal COmponent Factor ...

  8. Development of Polyester/Eggshell Particulate Composites

    Directory of Open Access Journals (Sweden)

    S.N. Patrick


    Full Text Available The development of Polyester/Eggshell particulate composites has been carried out. Uncarbonized and carbonized eggshell particles were used as reinforcement in polyester matrix. 10 to 50 wt% eggshell particles at intervals of 10 wt% were added to polyester as reinforcement. The microstructural analyses of the polyester/eggshell particulate composites were carried out using SEM and EDS. The mechanical properties and density were carried out by standard methods. The results showed that the density and hardness values of the polyester/eggshell particulate composite increased steadily with increasing eggshell addition. The tensile strength increased from 15.182 N/mm2 at 0 wt% eggshell addition to a maximum of 23.4 N/mm2 at 40 wt% eggshell addition for uncarbonized eggshell; while it increased to a maximum of 28.378 N/mm2 at 20 wt% eggshell addition for carbonized eggshell. Compressive strength increased steadily from 90.3 N/mm2 at 0 wt% eggshell additions to a maximum of 103.6 at 50 wt% eggshell addition for uncarbonized eggshell and 116.5N/mm2 at 50 % eggshell addition for carbonized eggshell. Hardness value increased from 91 HRF at 0 % eggshell addition to a maximum of 120.05HRF at 50 wt% eggshell addition for uncarbonized eggshell and 149.45HRF at 50 wt% eggshell for the carbonized eggshell. Flexural strength increased from 76.06 N/mm2 at 0 wt% eggshell addition to a maximum of 97.06 N/mm2 at 40 wt% eggshell addition for uncarbonized eggshell; however, it increased to a maximum of 106.66 N/mm2 at 20 wt% eggshell addition for the carbonized eggshell. The impact energy also increased from 0.1 Joules at 0 wt% eggshell addition to a maximum of 0.35 Joules at 30 wt% eggshell addition for uncarbonized eggshell; it however increased to a maximum of 0.45 Joules at 20 wt% eggshell addition for the carbonized eggshell. Hence the development of polyester/eggshell particulate composites material with good mechanical properties and light weight which is

  9. Particulate nitrogen and phosphorus in the East China Sea and its adjacent Kuroshio waters and evaluation of budgets for the East China Sea Shelf (United States)

    Zuo, Jiulong; Song, Jinming; Yuan, Huamao; Li, Xuegang; Li, Ning; Duan, Liqin


    Nitrogen (N) and phosphorus (P) in suspended particles are important to the cycles of N and P in marine ecosystem. Suspended particles were collected from the East China Sea (ECS) and its adjacent Kuroshio waters to investigate the composing and distribution characteristics of particulate inorganic and organic nitrogen and phosphorus (PIN, PIP, PON and POP, respectively). The particulate N and P concentrations were fairly low in the Kuroshio water but much higher in the ECS water, especially in nearshore waters. PON and PIP were the dominant forms of particulate N and P, with an exception that POP was the major form of particulate P in the Kuroshio upper water. The regime of particulate N and P in the ECS was strongly influenced by riverine input, oceanic input, ocean current and photosynthesis. Among them, PON and POP were mainly from biogenic source, while PIN and PIP were originated from biogenic and external sources. And sedimentation, remineralization and resuspension were important influencing factors for the vertical distributions of particulate N and P. The budgets of particulate N and P for the ECS Shelf during rainy season (May-October) were also evaluated. The total particulate N and P (TPN and TPP) fluxes from oceanic input are respectively 10.99 and 2.49 times of those from riverine input. And oceanic input contains more POP, which is liable to be decomposed into phosphate, than riverine input. Furthermore, particulate nutrients fluxes from photosynthesis are the overriding source of total influxes for the ECS Shelf, accounting for 90.93% of TPN and 89.37% of TPP influxes. As for the photosynthetic fixed N and P, only 6.17% and 7.60% of them can reach the seafloor, while up to 87.73% and 60.06% of them are likely to be remineralized. The POP-rich oceanic input and the intensive photosynthesis and remineralization processes play important roles in the biogeochemical cycles of N and P in the ECS.

  10. Tonopah Test Range Air Monitoring: CY2012 Meteorological, Radiological, and Airborne Particulate Observations

    Energy Technology Data Exchange (ETDEWEB)

    Mizell, Steve A; Nikolich, George; Shadel, Craig; McCurdy, Greg; Miller, Julianne J


    401. This difference may be the result of using filter media at Station 400 with a smaller pore size than the media used at the other two stations. Average annual gamma exposure at Station 401 is slightly greater than at Station 400 and 402. Average annual gamma exposure at all three TTR stations are in the upper range to slightly higher than values reported for the CEMP stations surrounding the TTR. At higher wind speeds, the saltation counts are greater at Station 401 than at Station 402 while the suspended particulate concentrations are greater at Station 402 than at Statin 401. Although these observations seem counterintuitive, they are likely the result of differences in the soil material present at the two sites. Station 401 is located on an interfluve elevated above two adjacent drainage channels where the soil surface is likely to be composed of coarser material. Station 402 is located in finer sediments at the playa edge and is also subject to dust from a dirt road only 500 m to the north. During prolonged high wind events, suspended dust concentrations at Station 401 peaked with the initial winds then decreased whereas dust concentrations at Station 402 peaked with each peak in the wind speed. This likely reflects a limited PM10 source that is quickly expended at Station 401 relative to an abundant PM10 source at Station 402. In CY2013, to facilitate comparisons between radiological analyses of collected dust, the filter media at all three stations will be standardized. In addition, a sequence of samples will be collected at Station 400 using both types of filter media to enable development of a mathematical relationship between the results derived from the two filter types. Additionally, having acquired approximately four years of observations at Stations 400 and 401 and a year of observations at Station 402, a period-of-record analysis of the radiological and airborne dust conditions will be undertaken.

  11. Chromium in water, suspended particles, sediments and biota in the Iraja River estuary

    Energy Technology Data Exchange (ETDEWEB)

    Pfeiffer, W.C.; Fiszman, M.; de Lacerda, L.D.; van Weerfelt, M.; Carbonell, N.


    Analyses of chromium concentrations in waters, suspended particles, bottom sediments, fish (Poecilia reticulata), plants (Paspalum vaginatum, Sesuvium portulacastrum, Philoxeros vermicularis), soils and barnacles (Balanus sp.) were performed from August 1976 to September 1980 in samples collected from the Iraja River and inside its estuary in Guanabara Bay (Rio de Janeiro, Brazil). Sediments and water from the Iraja River showed chromium concentrations of 17536 and 23.39 ppm--a thousand times higher than the published data for freshwater systems. Chromium removed from solution by bottom sediments reaches Guanabara Bay linked to particulate matter. Fish and emergent grass inside the river concentrate chromium from water and/or sediment, returning the metal to the system as detritus. Soil and plants inside the estuary concentrate chromium thirty and ten times higher than in the control area. The vegetal community exhibits a concentration factor smaller than that related to soil and prevents the return of chromium to the estuarine waters. Inside the Guanabara Bay, Balanus sp. appears to be an effective biological monitor as it concentrates chromium in soft tissues 10/sup 3/ times higher than values found in suspended particles (0.012 ml/sup -1/).

  12. PAH Accessibility in Particulate Matter from Road-Impacted Environments. (United States)

    Allan, Ian J; O'Connell, Steven G; Meland, Sondre; Bæk, Kine; Grung, Merete; Anderson, Kim A; Ranneklev, Sissel B


    Snowmelt, surface runoff, or stormwater releases in urban environments can result in significant discharges of particulate matter-bound polycyclic aromatic hydrocarbons (PAHs) into aquatic environments. Recently, more-specific activities such as road-tunnel washing have been identified as contributing to contaminant load to surface waters. However, knowledge of PAH accessibility in particulate matter (PM) of urban origin that may ultimately be released into urban surface waters is limited. In the present study, we evaluated the accessibility of PAHs associated with seven distinct (suspended) particulate matter samples collected from different urban sources. Laboratory-based infinite sink extractions with silicone rubber (SR) as the extractor phase demonstrated a similar pattern of PAH accessibility for most PM samples. Substantially higher accessible fractions were observed for the less-hydrophobic PAHs (between 40 and 80% of total concentrations) compared with those measured for the most-hydrophobic PAHs ( 5.5 were found in line with those commonly found for slowly or very slowly desorbing sediment-associated contaminants. PAHs with log Kow < 5.5 were found at higher desorbing rates. The addition of detergents did not influence the extractability of lighter PAHs but increased desorption rates for the heavier PAHs, potentially contributing to increases in the toxicity of tunnel-wash waters when surfactants are used. The implications of total and accessible PAH concentrations measured in our urban PM samples are discussed in a context of management of PAH and PM emission to the surrounding aquatic environment. Although we only fully assessed PAHs in this work, further study should consider other contaminants such as OPAHs, which were also detected in all PM samples.

  13. Effect of ozonation on particulate matter in broiler houses. (United States)

    Li, Q; Wang, L; Oviedo-Rondón, E; Parnell, C B


    The effects of ozonation on particulate matter were studied on a commercial broiler farm. The farm consisted of 4 identical tunnel-ventilated houses (12.8×152.4 m): 2 houses were treated with O3 (maximum concentration 0.1 ppm) and the other 2 served as control units. The particle size distributions of total suspended particulate (TSP) samples from both control and treated houses were found to have very similar profiles with no statistical difference. The TSP concentrations were significantly higher in treated houses as compared with those in control houses, and the mean of the differences was 5.50 mg/m3. In both treated and control houses, there were substantial vertical TSP concentration gradients and the concentrations decreased with height. At broiler chicken height (0.28 m), TSP concentrations were 13±3 mg/m3 in control houses and 17±2 mg/m3 in treated houses. At human breathing height (1.55 m), TSP concentrations were 8±4 mg/m3 in control houses and 7±2 mg/m3 in treated houses. Particle phase NH4+ concentrations were higher in treated houses (ranging from 0.59 to 42.01 mg/m3 with mean=17.49 mg/m3) than in control houses (ranging from 0.34 to 13.55 mg/m3 with mean=4.42 mg/m3). The TSP samples from locations in the vicinity of the farm showed higher concentrations downwind than that upwind, but there were no significant differences observed among different ambient locations for TSP NH4+ concentrations. The results from this study did not show that direct application of ozonation technique has beneficial effects for particulate matter control in broiler houses.

  14. Suspended sediment yield in Texas watersheds (United States)

    Coonrod, Julia Ellen Allred

    The Texas Water Development Board collected suspended sediment samples across the state of Texas for approximately 60 years. Until this research, no comprehensive analysis of the data had been conducted. This study compiles the suspended sediment data along with corresponding streamflow and rainfall. GIS programs are developed which characterize watersheds corresponding to the sediment gauging stations. The watersheds are characterized according to topography, climate, soils, and land use. All of the data is combined to form several SAS data sets which can subsequently be analyzed using regression. Annual data for all of the stations across the state are classified temporally and spatially to determine trends in the sediment yield. In general, the suspended sediment load increases with increasing runoff but no correlation exists with rainfall. However, the annual average rainfall can be used to classify the watersheds according to climate, which improves the correlation between sediment load and runoff. The watersheds with no dams have higher sediment loads than watersheds with dams. Dams in the drier parts of Texas reduce the sediment load more than dams in the wetter part of the state. Sediment rating curves are developed separately for each basin in Texas. All but one of the curves fall into a band which varies by about two orders of magnitude. The study analyzes daily time series data for the Lavaca River near Edna station. USGS data are used to improve the sediment rating curve by the addition of physically related variables and interaction terms. The model can explain an additional 41% of the variability in sediment concentration compared to a simple bivariate regression of sediment load and flow. The TWDB daily data for the Lavaca River near Edna station are used to quantify temporal trends. There is a high correlation between sediment load and flowrate for the Lavaca River. The correlation can be improved by considering a flow-squared term and by

  15. Determinants of exposure to particulate matter in textiles

    Directory of Open Access Journals (Sweden)

    Carlos Rosales


    Full Text Available (Received: 2015/05/11 - Accepted: 2015/06/03The objective of the research was to determine the exposure to particulate material in the textil area of a manufacturing company of linens and duvets, where it is carried out measurements of particulate material in respirable fraction 2.5 μg/m3. The same were made through the use of the equipment of direct reading and the results are compared with the value set limit. The study found that in the operation with the overlock machines is where there is a greater amount of particulate matter getting the maximum value in the entire production plant of 244 μg/m³, and a lower value machine in the bender with a value of 9 μg/m³ During the course of the investigation, it wanted to know the perception of the employees, to do this a survey was administered in a manner that takes first-hand the opinion with regard to the work. Among the results is that the staff is aware that there is particulate matter and if you have had respiratory complaints, indicate that the organization presents a great deal of commitment to the security and they also are involved in the tasks.

  16. High-temperature levitated materials

    National Research Council Canada - National Science Library

    Price, David L


    .... This can be avoided by suspending the sample through levitation. This technique also makes metastable states of matter accessible, opening up new avenues of scientific enquiry, as well as possible new materials for technological applications...

  17. Design consideration for magnetically suspended flywheel systems (United States)

    Anand, D.; Kirk, J. A.; Frommer, D. A.


    Consideration is given to the design, fabrication, and testing of a magnetically suspended flywheel system for energy storage applications in space. The device is the prototype of a system combining passive suspension of the flywheel plate by samarium cobalt magnets and active control in the radial direction using eight separate magnetic coils. The bearing assembly was machined from a nickel-iron alloy, and the machine parts are all hydrogen annealed. Slots in the magnetic plate allow four independent quadrants for control. The motor/generator component of the system is a brushless dc-permanent magnetic/ironless engine using electronic communication. The system has been tested at over 2500 rpm with satisfactory results. The system characteristics of the flywheel for application in low earth orbit (LEO) are given in a table.

  18. Organics and Suspended Solids Removal from Hospital

    Directory of Open Access Journals (Sweden)

    Fakhri Y. Hmood


    Full Text Available The Sequencing Batch Reactor (SBR method is used for treating samples of waste water taken from hospitals in Mosul. Many run periods are used (6-24 hours for             6 months. It is found that the organics and suspended solids removal increase with increasing the period of run, it is in the range ( 96-82 % and ( 100-95 % respectively, while the pH values are nearly neutral (7.05 to 7.5.     BOD5 and SS concentrations of the effluent are within the limits of Iraqi standards,  40:30 mg/l respectively. Hence, SBR method could be used for treating hospitals, small factories and some  residential sectors waste waters.  

  19. [Chemical Compositions and Sources Apportionment of Re-suspended Dust in Jincheng]. (United States)

    Wang, Yan; Peng, Lin; Li, Li-juan; Zhang, Teng; Liu, Hai-li; Mu, Ling


    In order to make effective plan to provide the scientific basis for prevention and control of re-suspended dust (RD), samples of particulate sources including RD and other pollution sources of Jincheng were collected. Elements, ions and carbon in particulate sources were analyzed. Enrichment factor, potential ecological risk assessment, and chemical mass balance model were used to analyze the chemical composition and the source of RD. The result indicated that the main components in RD of Jingeheng were Si, TC, Ca, OC, Al, Mg, Na, Fe, K and SO4(2-), contributing 61.14% of total mass of RD. The most abundant content of RD was crustal elements, and the ions were enriched in the fine particles. The mass fraction of OC in PM2. was higher, whereas the mass fraction of EC in PM10 was higher, indicating that secondary organic pollutants were mainly dominated in the fine particles. The dust PM2.5 and PM10 potential ecological risk indexes were extremely strong, and PM2.5 had higher ecological harm than PM10. Pb had the highest enrichment factor of 196.97 in PM2.5, which was followed by As, Cr, Ni, V, Zn and Cu, the enrichment factors of which were all greater than 10, indicating that they were apparently enriched and affected by human activities. Soil dust, construction dust, vehicle exhaust, and coal dust were the main sources of RD.

  20. Suspended-sediment rating curve response to urbanization and wildfire, Santa Ana River, California (United States)

    Warrick, J.A.; Rubin, D.M.


    River suspended-sediment concentrations provide insights to the erosion and transport of materials from a landscape, and changes in concentrations with time may result from landscape processes or human disturbance. Here we show that suspended-sediment concentrations in the Santa Ana River, California, decreased 20-fold with respect to discharge during a 34-year period (1968−2001). These decreases cannot be attributed to changes in sampling technique or timing, nor to event or seasonal hysteresis. Annual peak and total discharge, however, reveal sixfold increases over the 34-year record, which largely explain the decreases in sediment concentration by a nonlinear dilution process. The hydrological changes were related to the widespread urbanization of the watershed, which resulted in increases in storm water discharge without detectable alteration of sediment discharge, thus reducing suspended-sediment concentrations. Periodic upland wildfire significantly increased water discharge, sediment discharge, and suspended-sediment concentrations and thus further altered the rating curve with time. Our results suggest that previous inventories of southern California sediment flux, which assume time-constant rating curves and extend these curves beyond the sampling history, may have substantially overestimated loads during the most recent decades.

  1. Effects of Gravity and Shear on the Dynamics and Stability of Particulate and Multiphase Flows (United States)

    Sangani, Ashor S.


    The main objectives of this project are to understand the differing particulate and multiphase flow behaviors that will occur in space and in Earth's gravity. More specifically, the project is concerned with understanding the effect of shear and gravity on two relatively ideal suspensions with significant inertial effects. The first is a gas-solid suspension at small Reynolds numbers and finite Stokes numbers. In this type of suspensions the inertia of the particle phase is significant while the hydrodynamic interactions are dominated by viscous forces in the suspending fluid. The other is a bubble suspension at small Weber and large Reynolds numbers. The hydrodynamic interactions in such suspensions are dominated by the inertial effects in the suspending fluid, but these inertial interactions can be described using potential flow theory. Our main objective is to examine the effects of shear and gravity on the average properties and stability of these two suspensions.

  2. Effects of spring bloom phytoplankton dynamics and hydrography on the composition of settling material in the coastal northern Baltic Sea (United States)

    Tamelander, Tobias; Heiskanen, Anna-Stiina


    The phytoplankton species succession and sedimentation characteristics were studied on a sheltered and an open coastal station during a spring bloom in the northern Baltic Sea. Biomass (phytoplankton carbon and chlorophyll a), inorganic nutrients and particulate organic carbon and nitrogen (POC and PON) were determined in the suspended material. Sediment traps moored at different depths were used to determine the vertical flux of total particulate material (TPM), POC and PON, chlorophyll a, phaeopigments and phytoplankton carbon. The spring phytoplankton biomass was dominated by dinoflagellates that formed a dense bloom of short duration, whereas diatoms were present in the water column throughout the spring period in more moderate biomasses. The vertical flux of phytoplankton carbon was however dominated by diatoms at all times. The formation of resting stages increased the sedimentation of dinoflagellates, but compared to the suspended biomass of vegetative cells, their sinking rates were low. The ambient silicate concentration did probably not limit diatom growth; these were rather removed from the surface layer through sinking, a situation beneficial for dinoflagellates capable to exploit deep nutrient reserves through vertical migration. Due to rapid sinking soon after bloom formation and high specific loss rates, diatoms can be considered important contributors to the vertical flux of autochtonous material. Dinoflagellates mostly disintegrate in the water column and may settle as phytodetritus, except for the fraction of the populations that form rapidly sinking cysts. In addition to vertical export, advection of water from the stations seems to have been an important loss factor in the phytoplankton community. The two stations differed in that resuspension and input from littoral sources to the vertical flux were more important in the inner and shallower archipelago zone. This was also reflected in the C/N ratio of the settling material and in the bottom

  3. Associação entre material particulado de queimadas e doenças respiratórias na região sul da Amazônia brasileira Association between particulate matter from biomass burning and respiratory diseases in the southern region of the Brazilian Amazon

    Directory of Open Access Journals (Sweden)

    Cleber Nascimento do Carmo


    Full Text Available OBJETIVO: Investigar os efeitos de curto prazo da exposição ao material particulado de queimadas da Amazônia na demanda diária de atendimento ambulatorial por doenças respiratórias de crianças e de idosos. MÉTODOS: Estudo epidemiológico com delineamento ecológico de séries temporais. Os registros diários de atendimento ambulatorial foram obtidos nas 14 unidades de saúde do município de Alta Floresta, Mato Grosso, região sul da Amazônia brasileira, no período de janeiro de 2004 a dezembro de 2005. Informação sobre os níveis diários de material particulado fino foi disponibilizada pelo Instituto Nacional de Pesquisas Espaciais. Para controlar possíveis fatores de confusão (situações nas quais uma associação não causal entre exposição e doença é observada devido a uma terceira variável, foram adicionadas ao modelo variáveis referentes a tendência temporal, sazonalidade, temperatura, umidade relativa do ar, precipitação pluviométrica e efeitos de calendário (como ocorrência de feriados e finais de semana. Utilizou-se regressão de Poisson via modelos aditivos generalizados. RESULTADOS: Um incremento de 10 µg/m³ nos níveis de exposição ao material particulado esteve associado a aumentos de 2,9 e 2,6% nos atendimentos ambulatoriais por doenças respiratórias de crianças no 6º e 7º dias subsequentes à exposição. Não foram encontradas associações significativas nos atendimentos de idosos. CONCLUSÕES: Os resultados sugerem que os níveis de material particulado das queimadas na Amazônia estão associados a efeitos adversos à saúde respiratória de crianças.OBJECTIVE: To investigate the short-term effects of exposure to particulate matter from biomass burning in the Amazon on the daily demand for outpatient care due to respiratory diseases in children and the elderly. METHODS: Epidemiologic study with ecologic time series design. Daily consultation records were obtained from the 14 primary health

  4. Molecular composition of sugars in atmospheric particulate matter from interior Alaska (United States)

    Haque, Md. Mozammel; Kawamura, Kimitaka; Kim, Yongwon


    Sugars can account for 0.5-8% of carbon in atmospheric particulate matter, affecting the earth climate, air quality and public health. Total of 33 total suspended particle (TSP) samples were collected from Fairbanks, Alaska in June 2008 to June 2009 using a low volume air sampler. Here, we report the molecular characteristics of anhydro-sugars (levoglucosan, galactosan and mannosan), primary saccharides (xylose, fructose, glucose, sucrose and trehalose) and sugar alcohols (erythritol, arabitol, mannitol and inositol). The average contribution of sugars to the organic carbon (OC) was also determined to be 0.92%. Sugar compounds were measured using solvent extraction/TMS-derivatization technique followed by gas chromatography-mass spectrometry (GC-MS) determination. The concentrations of total quantified sugar compounds ranged from 2.3 to 453 ng m-3 (average 145 ng m-3). The highest concentration was recorded for levoglucosan in summer, with a maximum concentration of 790 ng m-3 (average 108 ng m-3). Levoglucosan, which is specifically formed by a pyrolysis of cellulose, has been used as an excellent tracer of biomass burning. The highest level of levoglucosan indicates a significant contribution of biomass burning in ambient aerosols. Galactosan (average 20 ng m-3) and mannosan (average 27 ng m-3), which are also formed through the pyrolysis of cellulose/hemicelluloses, were identified in all samples. The average concentrations of arabitol, mannitol, glucose and sucrose were also found 14.7, 14.6, 14.1 and 16.8 ng m-3, respectively. They have been proposed as tracers for resuspension of surface soil and unpaved road dust, which contain biological materials including fungi and bacteria. These results suggest that there is some impact of bioaerosols on climate over Interior Alaska. We will also measure water-soluble organic carbon (WSOC) and inorganic ions for all samples.


    Energy Technology Data Exchange (ETDEWEB)

    D.H. Pontius


    This quarterly report describes technical activities performed under Contract No. DE-AC21-94MC31160. The analyses of hot gas stream cleanup (HGCU) ashes and descriptions of filter performance studied under Task 1 of this contract are designed to address problems with filter operation that are apparently linked to characteristics of the collected ash. This report reviews the status of the HGCU data bank of ash and char characteristics, including the interactive querying of measured particulate properties. Task 1 plans for the remainder of the project include completion and delivery of the HGCU data bank, and issuance of a comprehensive final report on activities conducted under Task 1. Task 2 of this project concerns the testing and failure analyses of new and used filter elements and filter materials. Task 2 work during the past quarter included preliminary testing of two materials. One material tested was the soft candle filter manufactured by CGC and supplied by ABB. The other material was N610/mullite manufactured by Albany International (AIT).

  6. Chromogenic smart materials


    Lampert, Carl M.


    Smart materials cover a wide and developing range of technologies. A particular type of smart material, known as chromogenics, can be used for large area glazing in buildings, automobiles, planes, and for certain types of electronic display. These technologies consist of electrically-driven media including electrochromism, suspended particle electrophoresis, polymer dispersed liquid crystals, electrically heated thermotropics, and gaschromics.

  7. Particulate emissions from residential wood combustion: Final report: Norteast regional Biomass Program

    Energy Technology Data Exchange (ETDEWEB)


    The objective of this study was to provide a resource document for the Northeastern states when pursuing the analysis of localized problems resulting from residential wood combustion. Specific tasks performed include assigning emission rates for total suspended particulates (TSP) and benzo(a)pyrene (BaP) from wood burning stoves, estimating the impact on ambient air quality from residential wood combustion and elucidating the policy options available to Northeastern states in their effort to limit any detrimental effects resulting from residential wood combustion. Ancillary tasks included providing a comprehensive review on the relevant health effects, indoor air pollution and toxic air pollutant studies. 77 refs., 11 figs., 25 tabs.

  8. Relationship between vehicle count and particulate air pollution in Amman, Jordan. (United States)

    Alnawaiseh, Nedal Awad; Hashim, Jamal Hisham; Isa, Zaleha Md


    The main objective of this cross-sectional comparative study is to observe the relationship between traffic-related air pollutants, particularly particulate matter (PM) of total suspended particulate (TSP) and PM of size 10 µm (PM10), and vehicle traffic in Amman, Jordan. Two study areas were chosen randomly as a high-polluted area (HPA) and low-polluted area (LPA). The findings indicate that TSP and PM10 were still significantly correlated with traffic count even after controlling for confounding factors (temperature, relative humidity, and wind speed): TSP, r = 0.726, P relationship between traffic count and PM level: TSP, P relationship between temperature and PM10 level (P = .018). Traffic volume contributed greatly to high concentrations of TSP and PM10 in areas with high traffic count, in addition to the effect of temperature. © 2012 APJPH.

  9. Respirable particulate monitoring with remote sensors. (Public health ecology: Air pollution) (United States)

    Severs, R. K.


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

  10. A suspended sediment yield predictive equation for river basins in ...

    African Journals Online (AJOL)

    An empirical equation that can be used for estimating the suspended sediment yields of river drainage basins without sediment data has been established for basins in the sub-tropical forest Southwestern river basin system of Ghana. The power law equation relates mean annual specific suspended sediment yield (t km-2 ...

  11. Simulation of suspended sediment transport initialized with satellite ...

    Indian Academy of Sciences (India)

    Suspended sediment transport in the Gulf of Kachchh is simulated utilizing the suspended sediment concentration (SSC) derived from Oceansat OCM imagery, as the initial condition in MIKE-21 Mud. Transport model. Optimization of the model mud parameters, like settling velocity and critical shear stress for erosion are ...

  12. 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...

  13. A wave-resolving model for nearshore suspended sediment transport (United States)

    Ma, Gangfeng; Chou, Yi-Ju; Shi, Fengyan


    This paper presents a wave-resolving sediment transport model, which is capable of simulating sediment suspension in the field-scale surf zone. The surf zone hydrodynamics is modeled by the non-hydrostatic model NHWAVE (Ma et al., 2012). The turbulent flow and suspended sediment are simulated in a coupled manner. Three effects of suspended sediment on turbulent flow field are considered: (1) baroclinic forcing effect; (2) turbulence damping effect and (3) bottom boundary layer effect. Through the validation with the laboratory measurements of suspended sediment under nonbreaking skewed waves and surfzone breaking waves, we demonstrate that the model can reasonably predict wave-averaged sediment profiles. The model is then utilized to simulate a rip current field experiment (RCEX) and nearshore suspended sediment transport. The offshore sediment transport by rip currents is captured by the model. The effects of suspended sediment on self-suspension are also investigated. The turbulence damping and bottom boundary layer effects are significant on sediment suspension. The suspended sediment creates a stably stratified water column, damping fluid turbulence and reducing turbulent diffusivity. The suspension of sediment also produces a stably stratified bottom boundary layer. Thus, the drag coefficient and bottom shear stress are reduced, causing less sediment pickup from the bottom. The cross-shore suspended sediment flux is analyzed as well. The mean Eulerian suspended sediment flux is shoreward outside the surf zone, while it is seaward in the surf zone.

  14. Evaluation of the suspending properties of Cola acuminata gum on ...

    African Journals Online (AJOL)

    Many natural gums are employed as suspending agents in the formulation of pharmaceutical suspensions. The search to develop locally available natural gum from apparently a waste product as an alternative suspending agent stimulated the interest in this present study. Cola acuminata gum (CAG) extracted from Cola ...

  15. Simulation of suspended sediment transport initialized with satellite ...

    Indian Academy of Sciences (India)

    Suspended sediment transport in the Gulf of Kachchh is simulated utilizing the suspended sediment concentration (SSC) derived from Oceansat OCM imagery, as the initial condition in MIKE-21 Mud Transport model. Optimization of the model mud parameters, like settling velocity and critical shear stress for erosion are ...

  16. Evaluation of the suspending property of grewia gum in ...

    African Journals Online (AJOL)

    The suspending property of grewia gum in sulphadimidine suspension was evaluated. The gum was extracted by maceration, filtration, precipitation and drying techniques. It was used at 0.3 to 1% w/v as a suspending agent for sulphadimidine. Sodiumcarboxymethylcellulose (SCMC) and tragacanth were used as basis for ...

  17. Evaluation of the suspending properties of Adansonia digitata gum ...

    African Journals Online (AJOL)

    Sedimentation volume and rate, rheology, and ease of redispersion were employed as evaluation parameters. The results showed that both hot and cold water extracts of the gum used at 2-3 % w/v produced a better suspending property than 4 % w/v Compound Tragacanth gum. The suspending ability of the gums was in ...

  18. Evaluation of the Suspending Property of Grewia Gum in ...

    African Journals Online (AJOL)

    The suspending property of grewia gum in metronidazole suspension was evaluated. The gum was extracted by maceration, filtration, precipitation and drying techniques. It was used at 0.3 to 1% w/v as a suspending agent for metronidazole. Sodiumcarboxymethylcellulose (SCMC) and tragacanth were used as basis for ...


    Energy Technology Data Exchange (ETDEWEB)

    Ashley D. Williamson


    This quarterly report presents results and analysis of continuous onsite ambient fine particulate data at the North Birmingham sampling site during the October--December, 2001 study period. The continuous data include PM{sub 2.5} mass concentrations measured by TEOM, particle sulfate using the R&P 8400S monitor, particle size distributions measured by SMPS and APS monitors, and PM{sub 2.5} light scattering extinction coefficient as measured by nephelometer. The persistent daily trends described in the previous quarterly report are seen in the fall particulate data, superimposed on the seasonal trend toward lower concentrations in the cooler months. Some instrumental issues were noted with the APS and the sulfate monitoring instruments, as described in the main report.

  20. 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


    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.


    Energy Technology Data Exchange (ETDEWEB)

    Ashley D. Williamson


    This is the third quarterly progress report of the ''Southern Fine Particulate Monitoring Project'', funded by the U.S. Department of Energy's National Energy Technology Laboratory under DOE Cooperative Agreement No. DE-FC26-00NT40770 to Southern Research Institute (SRI). In this two year project SRI will conduct detailed studies of ambient fine particulate matter in the Birmingham, AL metropolitan area. Project objectives include: Augment existing measurements of primary and secondary aerosols at an established urban southeastern monitoring site; Make a detailed database of near-continuous measurements of the time variation of fine particulate mass, composition, and key properties (including particle size distribution); Apply the measurements to source attribution, time/transport properties of fine PM, and implications for management strategies for PM{sub 2.5}; and Validate and compare key measurement methods used in this study for applicability within other PM{sub 2.5} research by DOE-FE, EPA, NARSTO, and others. During the third project quarter, the new SRI air monitoring shelter and additional instruments were installed at the site. Details include: Installation of Radiance Research M903 Nephelometer; Installation of SRI air monitoring shelter at North Birmingham Site; Relocation of instruments from SEARCH shelter to SRI shelter; Installation of Rupprecht & Patashnick 8400 Sulfate Monitor; Assembly and initial laboratory testing for particulate sulfate monitor of Harvard design; Efficiency testing of particle sizing instrument package at SRI lab; Preparation for the Eastern Supersite July measurement intensive program; and Continued monitoring with TEOM and particle sizing instruments.


    Energy Technology Data Exchange (ETDEWEB)

    Ashley D. Williamson


    This is the second quarterly progress report of the ''Southern Fine Particulate Monitoring Project'', funded by the U.S. Department of Energy's National Energy Technology Laboratory under DOE Cooperative Agreement No. DE-FC26-00NT40770 to Southern Research Institute (SRI). In this two year project SRI will conduct detailed studies of ambient fine particulate matter in the Birmingham, AL metropolitan area. Project objectives include: Augment existing measurements of primary and secondary aerosols at an established urban southeastern monitoring site; Make a detailed database of near-continuous measurements of the time variation of fine particulate mass, composition, and key properties (including particle size distribution); Apply the measurements to source attribution, time/transport properties of fine PM, and implications for management strategies for PM{sub 2.5}; and Validate and compare key measurement methods used in this study for applicability within other PM{sub 2.5} research by DOE-FE, EPA, NARSTO, and others.

  3. NewIn-situ synthesis method of magnesium matrix composites reinforced with TiC particulates

    Directory of Open Access Journals (Sweden)

    Zhang Xiuqing


    Full Text Available Magnesium matrix composites reinforced with TiC particulates was prepared using a new in-situ synthesis method of remelting and dilution technique. And measurements were performed on the composites. The results of x ray diffraction (XRD analysis confirmed that TiC particulates were synthesized during the sintering process, and they retained in magnesium matrix composites after the remelting and dilution processing. From the microstructure characterization and electron probe microanalysis (EPMA, we could see that fine TiC particulates distributed uniformly in the matrix material.

  4. Measuring the height-to-height correlation function of corrugation in suspended graphene

    Energy Technology Data Exchange (ETDEWEB)

    Kirilenko, D.A., E-mail: [Ioffe Institute, Politekhnicheskaya ul. 26, 194021 St-Petersburg (Russian Federation); EMAT, Universiteit Antwerpen, Groenenborgerlaan 171, B-2020 Antwerpen (Belgium); Brunkov, P.N. [Ioffe Institute, Politekhnicheskaya ul. 26, 194021 St-Petersburg (Russian Federation); ITMO University, Kronverksky pr. 49, 197101 St. Petersburg (Russian Federation)


    Nanocorrugation of 2D crystals is an important phenomenon since it affects their electronic and mechanical properties. The corrugation may have various sources; one of them is flexural phonons that, in particular, are responsible for the thermal conductivity of graphene. A study of corrugation of just the suspended graphene can reveal much of valuable information on the physics of this complicated phenomenon. At the same time, the suspended crystal nanorelief can hardly be measured directly because of high flexibility of the 2D crystal. Moreover, the relief portion related to rapid out-of-plane oscillations (flexural phonons) is also inaccessible by such measurements. Here we present a technique for measuring the Fourier components of the height–height correlation function H(q) of suspended graphene which includes the effect of flexural phonons. The technique is based on the analysis of electron diffraction patterns. The H(q) is measured in the range of wavevectors q≈0.4–4.5 nm{sup −1}. At the upper limit of this range H(q) does follow the T/κq{sup 4} law. So, we measured the value of suspended graphene bending rigidity κ=1.2±0.4 eV at ambient temperature T≈300 K. At intermediate wave vectors, H(q) follows a slightly weaker exponent than theoretically predicted q{sup −3.15} but is closer to the results of the molecular dynamics simulation. At low wave vectors, the dependence becomes even weaker, which may be a sign of influence of charge carriers on the dynamics of undulations longer than 10 nm. The technique presented can be used for studying physics of flexural phonons in other 2D materials. - Highlights: • A technique for measuring free-standing 2D crystal corrugation is proposed. • The height-to-height correlation function of the suspended graphene corrugation is measured. • Various parameters of the intrinsic graphene properties are experimentally determined.

  5. Carbon sources in suspended particles and surface sediments from the Beaufort Sea revealed by molecular lipid biomarkers and compound-specific isotope analysis

    Directory of Open Access Journals (Sweden)

    I. Tolosa


    Full Text Available Molecular lipid biomarkers (hydrocarbons, alcohols, sterols and fatty acids and compound-specific isotope analysis of suspended particulate organic matter (SPM and surface sediments of the Mackenzie Shelf and slope (southeast Beaufort Sea, Arctic Ocean were studied in summer 2009. The concentrations of the molecular lipid markers, characteristic of known organic matter sources, were grouped and used as proxies to evaluate the relative importance of fresh algal, detrital algal, fossil, C3 terrestrial plants, bacterial and zooplankton material in the organic matter (OM of this area. Fossil and detrital algal contributions were the major fractions of the freshwater SPM from the Mackenzie River with ~34% each of the total molecular biomarkers. Fresh algal, C3 terrestrial, bacterial and zooplanktonic components represented much lower percentages, 17, 10, 4 and 80%, with a minor contribution of fossil and C3 terrestrial biomarkers. Characterization of the sediments revealed a major sink of refractory algal material mixed with some fresh algal material, fossil hydrocarbons and a small input of C3 terrestrial sources. In particular, the sediments from the shelf and at the mouth of the Amundsen Gulf presented the highest contribution of detrital algal material (60–75%, whereas those from the slope contained the highest proportion of fossil (40% and C3 terrestrial plant material (10%. Overall, considering that the detrital algal material is marine derived, autochthonous sources contributed more than allochthonous sources to the OM lipid pool. Using the ratio of an allochthonous biomarker (normalized to total organic carbon, TOC found in the sediments to those measured at the river mouth water, we estimated that the fraction of terrestrial material preserved in the sediments accounted for 30–40% of the total carbon in the inner shelf sediments, 17% in the outer shelf and Amundsen Gulf and up to 25% in the slope sediments. These estimates are low

  6. Characterization of flue gas desulfurization particulates in equalization basins

    Energy Technology Data Exchange (ETDEWEB)

    Meg M. Iannacone; James W. Castle; John H. Rodgers Jr. [Clemson University, Clemson, SC (United States). Department of Environmental Engineering and Earth Sciences


    Particulates in pilot-scale flue gas desulfurization (FGD) scrubber water were characterized by powder X-ray diffraction, scanning electron microscopy with energy dispersive spectroscopy, and size analysis based on Stokes' Law after settling in an equalization basin of a pilot-scale constructed wetland treatment system. Three sources were interpreted for specific particle types identified in samples analyzed: FGD wet scrubbing processes, coal combustion byproducts, and uncombusted material from coal. Gypsum (CaSO{sub 4}.2H{sub 2}O) from the FGD scrubbing process comprises 95% of the particulates. Iron oxide particles and cenospheres in the particulate samples are interpreted as coal combustion products. Particles interpreted as originating from unburned coal contain carbon and metals including Zn and Fe. The most abundant elements in the particulates analyzed are O, C, Ca, S, Fe, and Si, with maximum mean content of individual elements ranging from 13% to 70% among particle types. Less abundant elements include Al, K, Mg, Ti, and Mo, with maximum mean content from 0.1% to 3.8%. 41 refs., 5 figs., 5 tabs.

  7. Mechanical and physical properties of particulate reinforced composites


    Butsch, Susan Laurel


    The effect of particle size matching and mismatching on the processability, and the mechanical and physical properties of particulate reinforced composites is investigated in this study. These composites were made from dry powder-powder blends. Polymer and reinforcement materials were chosen, characterized and molded into composite plaques. For the same particle volume fraction (400/0), stiffness was found to increase, in general, as particle size decreased. The intimacy of mixing, stiffne...

  8. Aged riverine particulate organic carbon in four UK catchments

    Energy Technology Data Exchange (ETDEWEB)

    Adams, Jessica L., E-mail: [Centre for Ecology and Hydrology, Lancaster Environment Centre, Lancaster, LA1 4AP (United Kingdom); Tipping, Edward, E-mail: [Centre for Ecology and Hydrology, Lancaster Environment Centre, Lancaster, LA1 4AP (United Kingdom); Bryant, Charlotte L., E-mail: [NERC Radiocarbon Facility, East Kilbride G75 0QF, Scotland (United Kingdom); Helliwell, Rachel C., E-mail: [The James Hutton Institute, Craigiebuckler, Aberdeen AB15 8QH Scotland (United Kingdom); Toberman, Hannah, E-mail: [Centre for Ecology and Hydrology, Lancaster Environment Centre, Lancaster, LA1 4AP (United Kingdom); School of Environmental Sciences, University of Liverpool, Liverpool L69 3GP (United Kingdom); Quinton, John, E-mail: [Lancaster Environment Centre, Lancaster University, Lancaster LA1 4YQ (United Kingdom)


    The riverine transport of particulate organic matter (POM) is a significant flux in the carbon cycle, and affects macronutrients and contaminants. We used radiocarbon to characterise POM at 9 riverine sites of four UK catchments (Avon, Conwy, Dee, Ribble) over a one-year period. High-discharge samples were collected on three or four occasions at each site. Suspended particulate matter (SPM) was obtained by centrifugation, and the samples were analysed for carbon isotopes. Concentrations of SPM and SPM organic carbon (OC) contents were also determined, and were found to have a significant negative correlation. For the 7 rivers draining predominantly rural catchments, PO{sup 14}C values, expressed as percent modern carbon absolute (pMC), varied little among samplings at each site, and there was no significant difference in the average values among the sites. The overall average PO{sup 14}C value for the 7 sites of 91.2 pMC corresponded to an average age of 680 {sup 14}C years, but this value arises from the mixing of differently-aged components, and therefore significant amounts of organic matter older than the average value are present in the samples. Although topsoil erosion is probably the major source of the riverine POM, the average PO{sup 14}C value is appreciably lower than topsoil values (which are typically 100 pMC). This is most likely explained by inputs of older subsoil OC from bank erosion, or the preferential loss of high-{sup 14}C topsoil organic matter by mineralisation during riverine transport. The significantly lower average PO{sup 14}C of samples from the River Calder (76.6 pMC), can be ascribed to components containing little or no radiocarbon, derived either from industrial sources or historical coal mining, and this effect is also seen in the River Ribble, downstream of its confluence with the Calder. At the global scale, the results significantly expand available information for PO{sup 14}C in rivers draining catchments with low erosion rates

  9. Microorganisms associated particulate matter: a preliminary study. (United States)

    Alghamdi, Mansour A; Shamy, Magdy; Redal, Maria Ana; Khoder, Mamdouh; Awad, Abdel Hameed; Elserougy, Safaa


    This study aims to determine the microbiological quality of particulate matter (PM) in an urban area in Jeddah, Saudi Arabia, during December 2012 to April 2013. This was achieved by the determination of airborne bacteria, fungi, and actinobacteria associated PM10 and PM2.5, as well as their relationships with gaseous pollutants, O3, SO2 and NO2, and meteorological factors (T°C, RH% and Ws). High volume samplers with PM10 and PM2.5 selective sizes, and glass fiber filters were used to collect PM10 and PM2.5, respectively. The filters were suspended in buffer phosphate and aliquots were spread plated onto the surfaces of trypticase soy agar, malt extract agar, and starch casein agar media for counting of bacteria, fungi and actinobacteria-associated PM, respectively. PM10 and PM2.5 concentrations averaged 159.9 μg/m(3) and 60 μg/m(3), respectively, with the ratio of PM2.5/PM10 averaged ~0.4. The concentrations of O3, SO2 and NO2 averaged 35.73 μg/m(3), 38.1μg/m(3) and 52.5 μg/m(3), respectively. Fungi and actinobacteria associated PM were found in lower concentrations than bacteria. The sum of microbial loads was higher in PM10 than PM2.5, however a significant correlation (r=0.57, P ≤ 0.05) was found between the sum of microbial loads associated PM10 and PM2.5. Aspergillus fumigatus and Aspergillus niger were the common fungal types associated PM. Temperature significantly correlated with both PM10 (r=0.44), and PM2.5 (r=0.5). Significant negative correlations were found between O3 and PM2.5 (r=-0.47), and between SO2 with PM10 (r=-0.48). Wind speed positively correlated with airborne microorganisms associated PM. The regression model showed that the inverse PM2.5 concentration (1/PM2.5) was a significant determinant of fungal count associated PM. Chemical processes and environmental factors could affect properties of PM and in turn its biological quality. Copyright © 2014 Elsevier B.V. All rights reserved.

  10. On-road particulate emission measurement (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

  11. Diffusion processes in freely suspended smectic films (United States)

    Śliwa, I.; Zakharov, A. V.


    A molecular model describing translational diffusion in freely suspended smectic films (FSSFs) in air is proposed. This model is based on the random walk theory and allows calculation of the translational diffusion coefficient (TDC) across smectic layers (along the director). All values necessary for calculating the TDC are obtained within the generalized mean-field model considering not only anisotropic interactions between nearest neighbors of molecules forming FSSFs, but also the stabilizing effect of the smectic/air interface. The spatial inhomogeneity of order parameters over the FSSF section, arising in this case, results in the fact that the surface tension at the smectic/air interface not only suppresses thermal fluctuations in surface layers, but also completely suppresses translational diffusion of molecules from the FSSF to air. The results of calculations of dimensional translational diffusion in the bulk of the FSSF formed by 5- n-alkyl-2-(4- n-(perfluoroalkyl-metyleneoxy))pentyl molecules during its thinning show that the TDC monotonically increases as the smectic film is thinned.

  12. [Distributions and pollution status of heavy metals in the suspended particles of the estuaries and coastal area of eastern Hainan]. (United States)

    Xin, Cheng-Lin; Ren, Jing-Ling; Zhang, Gui-Ling; Shao, Ya-Ping; Zhang, Guo-Ling; Liu, Su-Mei


    The distributions and pollution status of heavy metals in the suspended particles were investigated in the Wanquan and Wenchang/Wenjiao estuaries and the coastal area of eastern Hainan in July 2008. The concentrations of metal elements (Al, Fe, Mn, Cr, Cu, Ni, V, Zn) were determined by ICP-AES after microwave digestion. Multivariate statistical methods (e. g. correlation analysis and principal factor analysis) were used to discuss the major factors controlling the variability of heavy metal concentrations and the pollution status in those areas. There was an obvious variability in particulate metal concentrations from upstream to estuary of both rivers. The concentrations first increased with increasing salinity and then decreased with further increase of the salinity; the concentrations were slightly higher at the coastal area in the east. The variability of particulate metal concentrations reduced significantly after the normalization by Al, indicating the effects of grain size. Enrichment factor calculation results showed that there was heavy metal pollution (especially Cu, Ni) in the Wenchang/Wenjiao River and estuary, while the situation in Wanquan River remained at pristine level. Concentrations of particulate metals in the study area were mainly controlled by source geology and provenance, as well as contamination from the discharge of waste water and biological activity.

  13. An extensive study of the concentrations of particulate/dissolved radiocaesium derived from the Fukushima Dai-ichi Nuclear Power Plant accident in various river systems and their relationship with catchment inventory. (United States)

    Yoshimura, Kazuya; Onda, Yuichi; Sakaguchi, Aya; Yamamoto, Masayoshi; Matsuura, Yuki


    An extensive investigation of particulate radiocaesium in suspended solids and dissolved radiocaesium in river water was undertaken at 30 sites in Fukushima and Miyagi Prefectures in December 2012, and their relationships with catchment inventory and the solid/liquid distribution coefficient (Kd) were evaluated. Rivers located in the coastal region on the north side of the Fukushima Dai-ichi Nuclear Power Plant exhibited relatively higher particulate radiocaesium concentrations. Significant correlations were found between concentrations of particulate/dissolved radiocaesium and average catchment inventories, indicating that the concentrations of particulate/dissolved radiocaesium could be approximated from the catchment inventory. Particulate radiocaesium concentration was significantly correlated with dissolved radiocaesium concentration (with the exception of concentrations measured in estuaries), and the geometric mean Kd was calculated as 3.6 × 10(5) with a 95% confidence interval of 2.6-5.1 × 10(5). Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. 76 FR 38694 - Uranium From Russia; Institution of a Five-Year Review Concerning the Suspended Investigation on... (United States)


    ... COMMISSION Uranium From Russia; Institution of a Five-Year Review Concerning the Suspended Investigation on Uranium From Russia AGENCY: United States International Trade Commission. ACTION: Notice. SUMMARY: The... on uranium from Russia would be likely to lead to continuation or recurrence of material injury...

  15. Temporal and Spatial Scales of Terrestrially-derived Particulate and Dissolved Material in the Penobscot River System: Quantifying Conserved and Non-conserved Optical Properties and Transformations Within the Estuary (United States)


    occur during periods of the largest tidal range (i.e. spring tides), indicating that processes of bottom sediment resuspension strongly control the...The goals of this project are to understand the role of large sediment fluxes on the dissolve organic materials. This mooring will also integrate an...Separating in situ and terrigenous sources of absorption by dissolved material in coastal waters. J. Geophys. Res. 106(C2): 2545-2560.

  16. Writing and functionalisation of suspended DNA nanowires on superhydrophobic pillar arrays

    KAUST Repository

    Miele, Ermanno


    Nanowire arrays and networks with precisely controlled patterns are very interesting for innovative device concepts in mesoscopic physics. In particular, DNA templates have proven to be versatile for the fabrication of complex structures that obtained functionality via combinations with other materials, for example by functionalisation with molecules or nanoparticles, or by coating with metals. Here, the controlled motion of the a three-phase contact line (TCL) of DNA-loaded drops on superhydrophobic substrates is used to fabricate suspended nanowire arrays. In particular, the deposition of DNA wires is imaged in situ, and different patterns are obtained on hexagonal pillar arrays by controlling the TCL velocity and direction. Robust conductive wires and networks are achieved by coating the wires with a thin layer of gold, and as proof of concept conductivity measurements are performed on single suspended wires. The plastic material of the superhydrophobic pillars ensures electrical isolation from the substrate. The more general versatility of these suspended nanowire networks as functional templates is outlined by fabricating hybrid organic-metal-semiconductor nanowires by growing ZnO nanocrystals onto the metal-coated nanowires.

  17. Writing and functionalisation of suspended DNA nanowires on superhydrophobic pillar arrays. (United States)

    Miele, Ermanno; Accardo, Angelo; Falqui, Andrea; Marini, Monica; Giugni, Andrea; Leoncini, Marco; De Angelis, Francesco; Krahne, Roman; Di Fabrizio, Enzo


    Nanowire arrays and networks with precisely controlled patterns are very interesting for innovative device concepts in mesoscopic physics. In particular, DNA templates have proven to be versatile for the fabrication of complex structures that obtained functionality via combinations with other materials, for example by functionalisation with molecules or nanoparticles, or by coating with metals. Here, the controlled motion of the a three-phase contact line (TCL) of DNA-loaded drops on superhydrophobic substrates is used to fabricate suspended nanowire arrays. In particular, the deposition of DNA wires is imaged in situ, and different patterns are obtained on hexagonal pillar arrays by controlling the TCL velocity and direction. Robust conductive wires and networks are achieved by coating the wires with a thin layer of gold, and as proof of concept conductivity measurements are performed on single suspended wires. The plastic material of the superhydrophobic pillars ensures electrical isolation from the substrate. The more general versatility of these suspended nanowire networks as functional templates is outlined by fabricating hybrid organic-metal-semiconductor nanowires by growing ZnO nanocrystals onto the metal-coated nanowires. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Molecular mechanistic origin of nanoscale contact, friction, and scratch in complex particulate systems. (United States)

    Jalilvand, Soroosh; Shahsavari, Rouzbeh


    Nanoscale contact mechanisms, such as friction, scratch, and wear, have a profound impact on physics of technologically important particulate systems. Determining the key underlying interparticle interactions that govern the properties of the particulate systems has been long an engineering challenge. Here, we focus on particulate calcium-silicate-hydrate (C-S-H) as a model system and use atomistic simulations to decode the interplay between crystallographic directions, structural defects, and atomic species on normal and frictional forces. By exhibiting high material inhomogeneity and low structural symmetry, C-S-H provides an excellent system to explore various contact-induced nanoscale deformation mechanisms in complex particulate systems. Our findings provide a deep fundamental understanding of the role of inherent material features, such as van der Waals versus Coulombic interactions and the role of atomic species, in controlling the nanoscale normal contact, friction, and scratch mechanisms, thereby providing de novo insight and strategies for intelligent modulation of the physics of the particulate systems. This work is the first report on atomic-scale investigation of the contact-induced nanoscale mechanisms in structurally complex C-S-H materials and can potentially open new opportunities for knowledge-based engineering of several other particulate systems such as ceramics, sands, and powders and self-assembly of colloidal systems in general.

  19. Sources and transformation of dissolved and particulate organic nitrogen in the North Pacific Subtropical Gyre indicated by compound-specific δ15N analysis of amino acids (United States)

    Yamaguchi, Yasuhiko T.; McCarthy, Matthew D.


    This study explores the use of compound-specific nitrogen isotopes of amino acids (δ15NAA) of coupled dissolved and particulate organic nitrogen (DON, PON) samples as a new approach to examine relative sources, transformation processes, and the potential coupling of these two major forms of N cycle in the ocean water column. We measured δ15NAA distributions in high-molecular-weight dissolved organic nitrogen (HMW DON) and suspended PON in the North Pacific Subtropical Gyre (NPSG) from surface to mesopelagic depths. A new analytical approach achieved far greater δ15NAA measurement precision for DON than earlier work, allowing us to resolve previously obscured differences in δ15NAA signatures, both with depth and between ON pools. We propose that δ15N values of total hydrolysable amino acids (THAA) represents a proxy for proteinaceous ON δ15N values in DON and PON. Together with bulk δ15N values, this allows δ15N values and changes in bulk, proteinaceous, and ;other-N; to be directly evaluated. These novel measurements suggest three main conclusions. First, the δ15NAA signatures of both surface and mesopelagic HMW DON suggest mainly heterotrophic bacterial sources, with mesopelagic HMW DON bearing signatures of far more degraded material compared to surface material. These results contrast with a previous proposal that HMW DON δ15NAA patterns are essentially ;pre-formed; by cyanobacteria in the surface ocean, undergo little change with depth. Second, different δ15NAA values and patterns of HMW DON vs. suspended PON in the surface NPSG suggest that sources and cycling of these two N reservoirs are surpisingly decoupled. Based on molecular δ15N signatures, we propose a new hypothesis that production of surface HMW DON is ultimately derived from subsurface nitrate, while PON in the mixed layer is strongly linked to N2 fixation and N recycling. In contrast, the comparative δ15NAA signatures of HMW DON vs. suspended PON in the mesopelagic also suggest a

  20. Variation in the Effect of Particulate Matter on Pulmonary Function in Schoolchildren in Western Japan and Its Relation with Interleukin-8. (United States)

    Watanabe, Masanari; Noma, Hisashi; Kurai, Jun; Sano, Hiroyuki; Kitano, Hiroya; Saito, Rumiko; Kimura, Yutaka; Aiba, Setsuya; Oshimura, Mitsuo; Shimizu, Eiji


    This study aimed to investigate the effects of particulate matter (PM) on pulmonary function in schoolchildren, as well as the relationships of these effects with interleukin-8. Morning peak expiratory flow (PEF) was measured daily in 399 children during April-May 2012, and in 384 of these children during March-May 2013. PEF's association with the daily levels of suspended particulate matter (SPM) and PM function in schoolchildren and daily levels of SPM and PM2.5, but this association may differ depending on the PM's ability to elicit interleukin-8 production.

  1. Diesel particulate filter with zoned resistive heater (United States)

    Gonze, Eugene V [Pinckney, MI


    A diesel particulate filter assembly comprises a diesel particulate filter (DPF) and a heater assembly. The DPF filters a particulate from exhaust produced by an engine. The heater assembly has a first metallic layer that is applied to the DPF, a resistive layer that is applied to the first metallic layer, and a second metallic layer that is applied to the resistive layer. The second metallic layer is etched to form a plurality of zones.

  2. Influence of charge carriers on corrugation of suspended graphene (United States)

    Kirilenko, Demid A.; Gorodetsky, Andrei; Baidakova, Marina V.


    Electronic degrees of freedom are predicted to play a significant role in mechanics of two-dimensional crystalline membranes. Here we show that appearance of charge carriers may cause a considerable impact on suspended graphene corrugation, thus leading to additional mechanism resulting in charge carriers mobility variation with their density. This finding may account for some details of suspended graphene conductivity dependence on its doping level and suggests that proper modeling of suspended graphene-based device properties must include the influence of charge carriers on its surface corrugation.

  3. Raman study of lysozyme amyloid fibrils suspended on super-hydrophobic surfaces by shear flow

    KAUST Repository

    Moretti, Manola


    The shear flow generated at the rim of a drop evaporating on a micro-fabricated super-hydrophobic surface has been used to suspend and orient single/few lysozyme amyloid fibrils between two pillars for substrate-free characterization. Micro Raman spectroscopy performed on extended fibers evidenced a shift of the Amide I band main peak to the value attributed to β-sheet secondary structure, characteristic of the amyloid fibers. In addition, given the orientation sensitivity of the anisotropic molecule, the Raman signal of the main secondary structure was nicely enhanced for a fiber alignment parallel to the polarization direction of the laser. The substrate-free sample generated by this suspending technique is suitable for other structural analysis methods, where fiber crystals are investigated. It could be further employed for generation of arrays and patterns in a controllable fashion, where bio-compatible material is needed.

  4. Seasonal and spatial variability of light absorption by suspended particles in the southern Baltic: A mathematical description (United States)

    Meler, Justyna; Ostrowska, Mirosława; Stoń-Egiert, Joanna; Zabłocka., Monika


    This paper analyses the relationships between the light absorption coefficients at 440 nm ap(440) for particles suspended in the surface waters of the southern Baltic Sea and the concentrations of some optically significant constituents in these waters. The analysis covers two main groups of particles: phytoplankton and non-algal. For this purpose we use the extensive database of optical measurements acquired from 2006 to 2013 during 40 cruises of r/v Oceania in various regions of the southern Baltic: open waters, coastal waters, the Gulf of Gdańsk, the Pomeranian Bay and river mouths. Expressions are derived for each of these regions to describe the seasonal variations of the dependence of the light absorption coefficients for phytoplankton aph(440) and non-algal particles aNAP(440) on concentrations of chlorophyll a (Tchla) and suspended particulate matter in sea water (SPM). With a knowledge of these dependences, one can determine the overall absorption coefficient for all suspended particles in any part of the Baltic Sea in particular seasons from known Tchla and SPM concentrations using the relationship ap(440) = aph(440) + aNAP(440) = f(Tchla, SPM). These dependences reflect the characteristics of a study area and season, and their application increases the accuracy of determination of the overall absorption properties of suspended particles and their main constituents as confirmed by statistical error reduction, e.g. standard error factor falls from 1.46 to 1.38. The relationships derived in this work can be applied in the local remote sensing algorithms used for monitoring the southern Baltic.

  5. Electrical isolation of dislocations in Ge layers on Si(001 substrates through CMOS-compatible suspended structures

    Directory of Open Access Journals (Sweden)

    Vishal Ajit Shah, Maksym Myronov, Chalermwat Wongwanitwatana, Lewis Bawden, Martin J Prest, James S Richardson-Bullock, Stephen Rhead, Evan H C Parker, Terrance E Whall and David R Leadley


    Full Text Available Suspended crystalline Ge semiconductor structures are created on a Si(001 substrate by a combination of epitaxial growth and simple patterning from the front surface using anisotropic underetching. Geometric definition of the surface Ge layer gives access to a range of crystalline planes that have different etch resistance. The structures are aligned to avoid etch-resistive planes in making the suspended regions and to take advantage of these planes to retain the underlying Si to support the structures. The technique is demonstrated by forming suspended microwires, spiderwebs and van der Pauw cross structures. We finally report on the low-temperature electrical isolation of the undoped Ge layers. This novel isolation method increases the Ge resistivity to 280 Ω cm at 10 K, over two orders of magnitude above that of a bulk Ge on Si(001 layer, by removing material containing the underlying misfit dislocation network that otherwise provides the main source of electrical conduction.

  6. Particulate hot gas stream cleanup technical issues

    Energy Technology Data Exchange (ETDEWEB)



    This is the eleventh in a series of quarterly reports describing the activities performed under Contract No. DE-AC21-94MC31160. Analyses of Hot Gas Stream Cleanup (HGCU) ashes and descriptions of filter performance address aspects of filter operation that are apparently linked to the characteristics of the collected ash or the performance of the ceramic bed filter elements. Task 1 is designed to generate a data base of the key characteristics of ashes collected from operating advanced particle filters (APFS) and to relate these ash properties to the operation and performance of these filters. Task 2 concerns testing and failure analysis of ceramic filter elements. Under Task 1 during the past quarter, analyses were completed on samples obtained during a site visit to the Power Systems Development Facility (PSDF). Analyses are in progress on ash samples from the Advanced Particulate Filter (APF) at the Pressurized Fluidized-Bed Combustor (PFBC) that was in operation at Tidd and ash samples from the Pressurized Circulating Fluid Bed (PCFB) system located at Karhula, Finland. An additional analysis was performed on a particulate sample from the Transport Reactor Demonstration Unit (TRDU) located at the University of North Dakota Energy and Environmental Research Center. A manuscript and poster were prepared for presentation at the Advanced Coal-Based Power and Environmental Systems `97 Conference scheduled for July 22 - 24, 1997. A summary of recent project work covering the mechanisms responsible for ash deposit consolidation and ash bridging in APF`s collecting PFB ash was prepared and presented at FETC-MGN in early July. The material presented at that meeting is included in the manuscript prepared for the Contractor`s Conference and also in this report. Task 2 work during the past quarter included mechanical testing and microstructural examination of Schumacher FT20 and Pall 326 as- manufactured, after 540 hr in service at Karhula, and after 1166 hr in service at

  7. Fabrication of SiC particulate reinforced polyester matrix composite and investigation (United States)

    Selvam, R.; Ravi, S.; Raja, R.


    Polymer composite provokes a new alternative material to engineering and domestic application. Polymeric nano composite have been intensively investigated due to the performance improvement when a small amount of nano sized particulates are added to matrix. The distinguished properties of SiC particulates influence to make a polymeric composite. This composite material has many application such as mechanical, automobile, marine, appliances and packaging. The composite material is fabricated in deferent weight ratio and it is characterized to understand the mechanical behavior, which was studied by various testing method under external load.

  8. Short-term changes in particulate fluxes measured by drifting sediment traps during end summer oligotrophic regime in the NW Mediterranean Sea

    Directory of Open Access Journals (Sweden)

    J. C. Marty


    Full Text Available Short-term changes in the flux of particulate matter were determined in the central north western Mediterranean Sea (near DYFAMED site using drifting sediment traps at 200 m depth in the course of the DYNAPROC 2 cruise (14 September–17 October 2004. In this period of marked water column stratification, POC fluxes varied by an order of magnitude, in the range of 0.03–0.29 mgC m−2 h−1 over the month and showed very rapid and high variations. Particulate carbon export represented less than 5% of integrated primary production, suggesting that phytoplankton production was essentially sustained by internal recycling of organic matter and retained within the photic zone. While PON and POP fluxes paralleled one another, the elemental ratios POC/PON and POC/POP, varied widely over short-term periods. Values of these ratios generally higher than the conventional Redfield ratio, together with the very low chlorophyll a flux recorded in the traps (mean 0.017 μg m−2 h−1, and the high phaeopigment and acyl lipid hydrolysis metabolite concentrations of the settling material, indicated that the organic matter reaching 200 m depth was reworked (by grazing, fecal pellets production, degradation and that algal sinking, dominated by nano- and picoplankton, made a small contribution to the downward flux. Over time, the relative abundance of individual lipid classes in organic matter (OM changed from glycolipids-dominated to neutral (wax esters, triacylglycerols and phospholipids-dominated, suggesting ecosystem maturation as well as rapid and continual exchanges between dissolved, suspended and sinking pools. Our most striking result was documenting the rapid change in fluxes of the various measured parameters. In the situation encountered here, with dominant regenerated production, a decrease of fluxes was noticed during windy periods (possibly through reduction of grazing. But fluxes increased as soon as calm

  9. Bioresponsive materials (United States)

    Lu, Yue; Aimetti, Alex A.; Langer, Robert; Gu, Zhen


    'Smart' bioresponsive materials that are sensitive to biological signals or to pathological abnormalities, and interact with or are actuated by them, are appealing therapeutic platforms for the development of next-generation precision medications. Armed with a better understanding of various biologically responsive mechanisms, researchers have made innovations in the areas of materials chemistry, biomolecular engineering, pharmaceutical science, and micro- and nanofabrication to develop bioresponsive materials for a range of applications, including controlled drug delivery, diagnostics, tissue engineering and biomedical devices. This Review highlights recent advances in the design of smart materials capable of responding to the physiological environment, to biomarkers and to biological particulates. Key design principles, challenges and future directions, including clinical translation, of bioresponsive materials are also discussed.

  10. Ratios of total suspended solids to suspended sediment concentrations by particle size (United States)

    Selbig, W.R.; Bannerman, R.T.


    Wet-sieving sand-sized particles from a whole storm-water sample before splitting the sample into laboratory-prepared containers can reduce bias and improve the precision of suspended-sediment concentrations (SSC). Wet-sieving, however, may alter concentrations of total suspended solids (TSS) because the analytical method used to determine TSS may not have included the sediment retained on the sieves. Measuring TSS is still commonly used by environmental managers as a regulatory metric for solids in storm water. For this reason, a new method of correlating concentrations of TSS and SSC by particle size was used to develop a series of correction factors for SSC as a means to estimate TSS. In general, differences between TSS and SSC increased with greater particle size and higher sand content. Median correction factors to SSC ranged from 0.29 for particles larger than 500m to 0.85 for particles measuring from 32 to 63m. Great variability was observed in each fraction-a result of varying amounts of organic matter in the samples. Wide variability in organic content could reduce the transferability of the correction factors. ?? 2011 American Society of Civil Engineers.

  11. Association between particulate matter air pollution and monthly inhalation and nebulization procedures in Ribeirão Preto, São Paulo State, Brazil Associação entre a poluição atmosférica por material particulado e contagens mensais de procedimentos de inalação e nebulização em Ribeirão Preto, São Paulo, Brasil

    Directory of Open Access Journals (Sweden)

    Estela Cristina Carneseca


    Full Text Available The study was designed to investigate the impact of air pollution on monthly inhalation/nebulization procedures in Ribeirão Preto, São Paulo State, Brazil, from 2004 to 2010. To assess the relationship between the procedures and particulate matter (PM10 a Bayesian Poisson regression model was used, including a random factor that captured extra-Poisson variability between counts. Particulate matter was associated with the monthly number of inhalation/nebulization procedures, but the inclusion of covariates (temperature, precipitation, and season of the year suggests a possible confounding effect. Although other studies have linked particulate matter to an increasing number of visits due to respiratory morbidity, the results of this study suggest that such associations should be interpreted with caution.O objetivo foi investigar os possíveis efeitos da poluição atmosférica nas contagens mensais de procedimentos de inalação/nebulização no Município de Ribeirão Preto, São Paulo, Brasil, no período de 2004 a 2010. Para verificar a relação existente entre os procedimentos e o material particulado (MP10 foi assumido um modelo bayesiano de regressão de Poisson, na presença de um fator aleatório que captura a variabilidade extra Poisson entre as contagens. O material particulado mostrou-se associado ao número de inalações/nebulizações, mas a inserção de covariáveis (temperatura, precipitação e estação sugere um possível efeito de confundimento. Embora outros estudos relacionem o material particulado com o aumento do número de atendimentos em decorrência de morbidades, os resultados do presente trabalho sugerem que estas associações devem ser interpretadas com cautela.

  12. Suspended sediment concentration profiles from synoptic satellite observations

    Digital Repository Service at National Institute of Oceanography (India)

    Ramakrishnan, R.; Rajawat, A; Chauhan, O.S.

    A method is developed to estimate vertical suspended sediment concentration (SSC) profiles in Gulf of Kachchh, from the sediment concentration values derived from synoptic observations of Ocean Colour Monitor (OCM). Under the influence of currents...

  13. Particles matter: Transformation of suspended particles in constructed wetlands

    NARCIS (Netherlands)

    Mulling, B.T.M.


    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. Leaching behaviour of different scrap materials at recovery and recycling companies: full-, pilot- and lab-scale investigation. (United States)

    Blondeel, E; Chys, M; Depuydt, V; Folens, K; Du Laing, G; Verliefde, A; Van Hulle, S W H


    Scrap material recovery and recycling companies are confronted with waste water that has a highly fluctuating flow rate and composition. Common pollutants, such as COD, nutrients and suspended solids, potentially toxic metals, polyaromatic hydrocarbons and poly chlorinated biphenyls can exceed the discharge limits. An analysis of the leaching behaviour of different scrap materials and scrap yard sweepings was performed at full-scale, pilot-scale and lab-scale in order to find possible preventive solutions for this waste water problem. The results of these leaching tests (with concentrations that frequently exceeded the Flemish discharge limits) showed the importance of regular sweeping campaigns at the company, leak proof or covered storage of specific scrap materials and oil/water separation on particular leachates. The particulate versus dissolved fraction was also studied for the pollutants. For example, up to 98% of the polyaromatic hydrocarbons, poly chlorinated biphenyls and some metals were in the particulate form. This confirms the (potential) applicability of sedimentation and filtration techniques for the treatment of the majority of the leachates, and as such the rainwater run-off as a whole. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. Preoperative embolization of nasopharyngeal angiofibromas: The role of direct percutaneous injection of cyanoacrylate glue in conjunction with particulate endovascular approach

    Directory of Open Access Journals (Sweden)

    Mohamed Abdel Hakim Osman Kasem


    Conclusion: The embolization of nasopharyngeal angiofibromas before surgery using percutaneous cyanoacrylate glue with endovascular particulate material proved to efficiently devascularize these tumours with lower blood loss during surgery and no major procedural complications.

  16. Dans le tourbillon des particules

    CERN Document Server

    Zito, Marco


    Accélérateurs géants, détecteurs complexes, particules énigmatiques... La physique subatomique peut sembler bien intimidante pour le novice. Et pourtant, qui n a jamais entendu parler du boson de Higgs et du CERN, le laboratoire européen où il a été découvert en 2012 ? Nul besoin d être un spécialiste pour comprendre de quoi il s agit. Aujourd hui, une théorie extraordinairement élégante, le Modèle Standard, décrit tous les résultats des expériences dans le domaine. Trente-sept particules élémentaires et quatre forces fondamentales : c est tout ce dont nous avons besoin pour expliquer la matière et l Univers ! Ce livre, destiné à un large public, raconte sans équations le long parcours qui a abouti au Modèle Standard. Ce parcours, parfois sinueux, a été entamé lorsque les Grecs anciens, et peut-être d autres avant eux, ont imaginé que la matière est composée de petites « billes ». Il faudra attendre plusieurs siècles pour qu on réalise que la matière, à l échelle micros...

  17. Southern Fine Particulate Monitoring Project

    Energy Technology Data Exchange (ETDEWEB)

    Ashley Williamson


    This final project report presents experimental details, results and analysis of continuous onsite ambient fine particulate data at the North Birmingham sampling site during the October, 2001-September, 2002 study period.The host site for these measurement activities is the North Birmingham PM monitoring station by the Jefferson County Health Department in Birmingham, AL.The continuous data include PM{sub 2.5} mass concentrations measured by TEOM, particle sulfate using the R&P 8400S monitor, particle size distributions measured by SMPS and APS monitors, and PM{sub 2.5} light scattering extinction coefficient as measured by nephelometer. During the course of the project, measurement intercomparison data were developed for these instruments and several complementary measurements at the site. The report details the instrument set and operating procedures and describes the resulting data. Report subsections present an overview summary of the data, followed by detailed description of the systematic time behavior of PM{sub 2.5} and other specific particulate size fractions. Specific subsections are included for particle size distribution, light scattering, and particle sulfate data. The final subsection addresses application of the measurements to the practical questions of fine PM generation and transport, source attribution, and PM{sub 2.5} management strategies.


    Particulate matter (PM), a component of air pollution has been epidemiologically associated with sudden deaths, cardiovascular and respiratory illnesses. The effects are more pronounced in patients with pre-existing conditions such as asthma, diabetes or obstructive pulmonary disorders. Clinical and experimental studies have historically focused on the cardiopulmonary effects of PM. However, since PM particles carry numerous biocontaminants that are capable of triggering free radical production and cytokine release, the possibility that PM may affect organs systems sensitive to oxidative stress must be considered. Four independent studies that summarize the neurochemical and neuropathological changes found in the brains of PM exposed animals are described here. These were recently presented at two 2007 symposia sponsored by the Society of Toxicology (Charlotte, NC) and the International Neurotoxicology Association (Monterey, CA). Particulates are covered with biocontaminants (e.g., endotoxins, mold, pollen) which convey free radical activity that can damage the lipids, nucleic acids, and proteins of target cells on contact and stimulate inflammatory cytokine release. Although, the historical focus of PM toxicity has been cardiopulmonary targets, it is now appreciated that inhaled nano-size (<100 nm) particles quickly exit the lungs and enter the circulation where they distribute to various organ systems (l.e., liver, kidneys, testes, lymph nodes) (Takenaka et aI

  19. Temporal variability and spatial distribution of suspended matter and organic C pool in the Zambezi River (United States)

    Teodoru, Cristian R.; Bouillon, Steven; Borges, Alberto V.; Darchambeau, François; Nyoni, Frank C.; Nyambe, Imasiku


    It is increasingly recognized that rivers are active components of global carbon (C) cycling, able of processing, emitting into atmosphere, and transporting to the oceans large quantities of both organic and inorganic carbon derived from the surrounding terrestrial landscape. Although tropical rivers contribute with more than half to the global freshwater discharge to the oceans, there is surprisingly little information on biogeochemistry and C cycling of those systems, especially for Africa. As part of a broader study on the biogeochemistry of large African river basins, we present here data on temporal and spatial variability of total suspended matter (TSM), particulate (POC) and dissolved organic C (DOC) in the Zambezi River (length = 2900 km, catchment area > 1.4 million km2, annual discharge ~ 4150 m3/s) in relation to physico-chemical proprieties (conductivity, oxygen, pH, total alkalinity), bacterial respiration, primary production and net aquatic metabolism. Data were collected along the entire river stretch during 2012 and 2013, and over 2 climatic (dry and wet) seasons to constrain the interannual variability, seasonality and spatial heterogeneity of the investigated parameters, and at two monitoring stations: one on the Zambezi mainstream, and one on the Kafue River (major tributary of the Zambezi; total length ~ 1900 km, catchment ~ 156, 000 km2, annual discharge = 350 m3/s), both located several km upstream their confluence. During the two sampled years, TSM concentrations varied from 1.6 mg/L to 110 mg/L (mean 17 in 2012 and 29 mg/L in 2013) and were systematically higher in the river mainstream (mean 21 mg/L and 36 mg/L in 2012 and 2013, respectively) compared to both reservoirs (the Kariba and the Cahora Bassa) where TSM concentrations average 2.5 mg/L. Despite the disturbance along the aquatic continuum caused by the presence of the two man-made reservoirs, a distinct longitudinal pattern was observed during both years, with TSM increasing

  20. Suspended-sediment and suspended-sand concentrations and loads for selected streams in the Mississippi River Basin, 1940-2009 (United States)

    Heimann, David C.; Cline, Teri L.; Glaspie, Lori M.


    This report presents suspended-sediment concentration and streamflow data, describes load-estimation techniques used in the computation of annual suspended-sediment loads, and presents annual suspended-sediment loads for 48 streamgaging stations within the Mississippi River Basin. Available published, unpublished, and computed annual total suspended-sediment and suspended-sand loads are presented for water years 1940 through 2009. When previously published annual loads were not available, total suspended-sediment and sand loads were computed using available data for water years 1949 through 2009. A table of suspended-sediment concentration and daily mean streamflow data used in the computation of annual loads is presented along with a table of compiled and computed annual suspended-sediment and suspended-sand loads, annual streamflows, and flow-weighted concentrations for the 48 stations.

  1. Suspended sediment apportionment in a South-Korean mountain catchment (United States)

    Birkholz, Axel; Meusburger, Katrin; Park, Ji-Hyung; Alewell, Christine


    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.

  2. Poly(methyl methacrylate) particulate carriers in drug delivery. (United States)

    Bettencourt, Ana; Almeida, António J


    Poly(methyl methacrylate) (PMMA) is one of the most widely explored biomedical materials because of its biocompatibility, and recent publications have shown an increasing interest in its applications as a drug carrier. PMMA-based particulate carriers (PMMA(P)) can be prepared either by polymerization methods or from pre-formed polymer-based techniques. Potential biomedical application of these particles includes their use as adjuvant for vaccines and carrier of many drugs as antibiotics and antioxidants via different routes of administration. Release of drugs from PMMA(P) occurs typically in a biphasic way with an incomplete drug release. To improve release profiles, recent strategies are focusing on increasing polymer hydrophilicity by synthesizing functionalized PMMA microspheres or by formulating PMMA composites with hydrophilic polymers. This review examines the current status of preparation techniques, drug release kinetics, biomedical applications and toxicity of these nano/micro PMMA-based particulate carriers.

  3. Origin and biochemical cycling of particulate nitrogen in the Mandovi estuary (United States)

    Fernandes, Loreta


    Mandovi estuary is a tropical estuary strongly influenced by the southwest monsoon. In order to understand, sources and fate of particulate organic nitrogen, suspended particulate matter (SPM) collected from various locations, was analyzed for particulate organic carbon (POC) and particulate organic nitrogen (PON), δ 13C POC, total hydrolysable amino acid enantiomers ( L- and D- amino acids) concentration and composition. δ 13C POC values were depleted (-32 to -25‰) during the monsoon and enriched (-29.6 to -21‰) in the pre-monsoon season implying that OM was derived from terrestrial and marine sources during the former and latter season, respectively. The biological indicators such as C/N ratio, D-amino acids, THAA yields and degradation indices (DI) indicate that the particulate organic matter (POM) was relatively more degraded during the monsoon season. Conversely, during the pre-monsoon, the biological indicators indicated the presence of relatively fresh and labile POM derived from autochthonous sources. Amino acids such as alanine, aspartic acid, leucine, serine, arginine, and threonine in monsoon and glutamic acid, glycine, valine, lysine, and isoleucine in pre-monsoon were relatively abundant. Presence of bacterial biomarker, D-amino acids in the SPM of the estuary during both the seasons signifies important contribution of bacteria to the estuarine detrital ON pool. Based on D-amino acid yields, bacterial OM accounted for 16-34% (23.0 ± 6.7%) of POC and 29-75% (47.9 ± 18.7%) of PON in monsoon, and 30-78% (50.0 ± 15%) of POC and 34-79% (51.2 ± 13.3%) of the PON in pre-monsoon in the estuary. Substantial contribution of bacterial-N to PON indicates nitrogen (N) enrichment on terrestrial POM during the monsoon season. Transport of terrestrial POM enriched with bacterial OM to the coastal waters is expected to influence coastal productivity and ecosystem functioning during the monsoon season.

  4. Tethering metal ions to photocatalyst particulate surfaces by bifunctional molecular linkers for efficient hydrogen evolution

    KAUST Repository

    Yu, Weili


    A simple and versatile method for the preparation of photocatalyst particulates modified with effective cocatalysts is presented; the method involves the sequential soaking of photocatalyst particulates in solutions containing bifunctional organic linkers and metal ions. The modification of the particulate surfaces is a universal and reproducible method because the molecular linkers utilize strong covalent bonds, which in turn result in modified monolayer with a small but controlled quantity of metals. The photocatalysis results indicated that the CdS with likely photochemically reduced Pd and Ni, which were initially immobilized via ethanedithiol (EDT) as a linker, were highly efficient for photocatalytic hydrogen evolution from Na2S-Na2SO3-containing aqueous solutions. The method developed in this study opens a new synthesis route for the preparation of effective photocatalysts with various combinations of bifunctional linkers, metals, and photocatalyst particulate materials. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. 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...

  6. Seasonal changes, spatial variability and origin of suspended organic matter in Hornsund, Spitsbergen (United States)

    Apolinarska, Karina; Szczuciński, Witold; Moskalik, Mateusz; Dominiczak, Aleksander


    Carbon stable isotope composition (δ13C) of suspended organic matter (SOM) was investigated to recognize temporal and spatial variability, as well as sources of particulate carbon delivered to the sediments of Hornsund fjord, Spitsbergen. Sampling was carried out between May 2015, when most of the investigated area was covered with sea-ice, and late August 2015. Samples were taken from a number of sites in central part of Hornsund, Burgerbukta, Samarinvegen and Brepolen bay in the innermost part of the fjord. One litre water volume, sampled from a range of depths between the water surface and 100 m, was filtered using GFF filters. δ13C values of the SOM were measured after acid treatment of the filters to remove carbonates. δ13C values of SOM varied both temporarily and spatially reflecting the variable sources of organic carbon, namely the marine production in situ, fresh marine organic carbon brought from the shelf with currents and "old" carbon delivered from land. The samples were most 13C-enriched (-22.4‰) in June, at the time of an intensive primary productivity within the fjord. Later, during the warm season, with the more intensive glaciers melting and thus supply of the suspended sediment load containing the old terrigenous carbon, δ13C values of SOM decreased in all the localities studied towards the carbon isotope values of the local terrestrial end-member, i.e., δ13C values of the old organic carbon in the bedrock. Change in δ13C values of SOM was also observed with increasing distance from glaciers, e.g. in front of the Samarinbreen and reflect changes in the intensity of primary production and supply of the old carbon. The study was supported from National Science Center grant No. 2013/10/E/ST10/00166.

  7. 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


    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...... attenuation coefficient of downwelling PAR (K (d)(PAR)), upwelling PAR (K (u)(PAR)), particle beam attenuation coefficient (c (p)), and irradiance reflectance R(-0, PAR). PAR is white light between 400 and 700 nm. The estuary receives melt water from the Greenland Inland Ice and stations covered a transect...

  8. A suspended core nanofiber with unprecedented large diameter ratio of holey region to core. (United States)

    Liao, Meisong; Chaudhari, Chitrarekha; Yan, Xin; Qin, Guanshi; Kito, Chihiro; Suzuki, Takenobu; Ohishi, Yasutake


    For a suspended core nanofiber, the holey region is expected to be as large as possible to propagate the light at wavelengths as long as possible. Additionally, a large holey region is significant for its applications in sensors. However, the fabrication of nanofiber with large holey region is still a challenge so far. In this paper a method, which involves pumping positive pressure of nitrogen gas in both the cane fabrication and fiber-drawing processes, was proposed. A suspended core nanofiber, with a core diameter of around 480 nm and an unprecedented diameter ratio of holey region to core (DRHC) of at least 62, was fabricated in the length of several hundred meters. Owing to the large holey region, the confinement loss of the suspended core nanofiber is insignificant when the wavelength of light propagated in it is 1700 nm. For this fabrication technique, the nanowire length, fabrication efficiency, and the uniformity in the diameter are much superior to those of the nanowires fabricated in other ways. Finally, single mode third harmonic generation was observed by this nanofiber under the pump of a 1557 nm femtosecond fiber laser. This work shows the prospect of fabrication of nanostructured waveguide in glass materials by an inflation technique.

  9. NOTE: Effects of powder additives suspended in dielectric on crater characteristics for micro electrical discharge machining (United States)

    Yeo, S. H.; Tan, P. C.; Kurnia, W.


    The effects of using powder additives suspended in dielectric on crater characteristics for micro electrical discharge machining (PSD micro-EDM) are investigated through the conduct of single RC discharge experiments at low discharge energies of 2.5 µJ, 5 µJ and 25 µJ. Through the introduction of additive particles into the dielectric, results of the single discharge experiments show the formation of craters with smaller diameters and depths, and having more consistent circular shapes than those produced in dielectric without additive. These craters also possess a noticeable morphological difference compared to those generated in dielectric without additive. In addition, discharge current measurements show a smaller amount of charges flowing between the tool electrode and workpiece, and at a slower flow rate when additives are present in the dielectric. Furthermore, based on the experimental results and findings from studies done in nanofluids, a hypothesis is made on the effects of powder suspended dielectric on the crater formation mechanism. The increased viscosity and enhanced thermal conductivity of a powder suspended dielectric lower the plasma heat flux into the electrode and raise the rate of heat dissipation away from the molten cavity. As a result, a smaller-sized crater having a larger amount of resolidified material within the crater cavity is formed.

  10. 7Be/210Pbxs Ratio as an Indicator of Suspended Sediment Age or Fraction New Sediment in Suspension (United States)

    Matisoff, G.; Wilson, C. G.; Whiting, P. J.


    We present a technique to use the 7Be/210Pbxs ratio as a measure of suspended sediment age or as an indicator of the fraction of the suspended sediment that is recently eroded from the landscape. Although both 7Be and 210Pbxs are delivered seasonally and stochastically to the landscape by precipitation, the ratio of the two radionuclides varies substantially less. The 7Be/210Pbxs ratios measured in three different watersheds decrease in the following manner: precipitation (~16) > suspended sediments in rivers (6-7) > suspended sediments in estuaries (4-6) > sediment collected in sediment traps in the estuary (~1) > surface sediment of the estuary (~0.5). Decreases in the 7Be/210Pbxs ratio in suspended sediments can be interpreted to be the result of increased age of the sediment, since 7Be decays faster than 210Pb. Alternatively, a decrease in the 7Be/210Pbxs ratio in suspended sediments can be interpreted to be the result of dilution of newly-tagged 7Be-rich sediment by 7Be-dead sediment, for example, by erosion of soil below the 7Be-enriched surface layer or by resuspension of 7Be-dead bottom sediment. We present a model which uses the 7Be/210Pbxs ratio in suspended sediments to determine the time since the particles were tagged by precipitation-derived radionuclides (i.e., the age of the suspended sediment). In addition, we present an alternative model to determine the fraction of the sediment that is `newly-tagged'. These two models are applied to three watersheds - Old Woman Creek, Ohio; Weeks Bay, Alabama; and South Slough, Oregon - and yield similar findings at all three sites. Sediment ages increase from 0 in newly tagged material to 50-80 days in rivers to about 80-100 days in the estuaries to about 200 days in the sediment traps to about 300 days on surface bottom sediments. Alternatively, the percent new sediment decreases from 100% in newly-tagged material to about 35-50% in rivers to 25-35% in the estuary to less than 10% in the sediment traps to 1

  11. Electrification of particulate entrained fluid flows—Mechanisms, applications, and numerical methodology

    Energy Technology Data Exchange (ETDEWEB)

    Wei, Wei [School of Energy and Power Engineering, Wuhan University of Technology, Wuhan, Hubei, 430063 (China); School of Human Settlements and Civil Engineering, Xi’an Jiaotong University, Xi’an, Shaanxi, 710049 (China); Gu, Zhaolin, E-mail: [School of Human Settlements and Civil Engineering, Xi’an Jiaotong University, Xi’an, Shaanxi, 710049 (China)


    Particulates in natural and industrial flows have two basic forms: liquid (droplet) and solid (particle). Droplets would be charged in the presence of the applied electric field (e.g. electrospray). Similar to the droplet charging, particles can also be charged under the external electric field (e.g. electrostatic precipitator), while in the absence of external electric field, tribo-electrostatic charging is almost unavoidable in gas–solid two-phase flows due to the consecutive particle contacts (e.g. electrostatic in fluidized bed or wind-blown sand). The particle charging may be beneficial, or detrimental. Although electrostatics in particulate entrained fluid flow systems have been so widely used and concerned, the mechanisms of particulate charging are still lack of a thorough understanding. The motivation of this review is to explore a clear understanding of particulate charging and movement of charged particulate in two-phase flows, by summarizing the electrification mechanisms, physical models of particulate charging, and methods of charging/charged particulate entrained fluid flow simulations. Two effective methods can make droplets charged in industrial applications: corona charging and induction charging. The droplet charge to mass ratio by corona charging is more than induction discharge. The particle charging through collisions could be attributed to electron transfer, ion transfer, material transfer, and/or aqueous ion shift on particle surfaces. The charges on charged particulate surface can be measured, nevertheless, the charging process in nature or industry is difficult to monitor. The simulation method might build a bridge of investigating from the charging process to finally charged state on particulate surface in particulate entrained fluid flows. The methodology combining the interface tracking under the action of the applied electric with the fluid flow governing equations is applicable to the study of electrohydrodynamics problems. The

  12. Electrification of particulate entrained fluid flows-Mechanisms, applications, and numerical methodology (United States)

    Wei, Wei; Gu, Zhaolin


    Particulates in natural and industrial flows have two basic forms: liquid (droplet) and solid (particle). Droplets would be charged in the presence of the applied electric field (e.g. electrospray). Similar to the droplet charging, particles can also be charged under the external electric field (e.g. electrostatic precipitator), while in the absence of external electric field, tribo-electrostatic charging is almost unavoidable in gas-solid two-phase flows due to the consecutive particle contacts (e.g. electrostatic in fluidized bed or wind-blown sand). The particle charging may be beneficial, or detrimental. Although electrostatics in particulate entrained fluid flow systems have been so widely used and concerned, the mechanisms of particulate charging are still lack of a thorough understanding. The motivation of this review is to explore a clear understanding of particulate charging and movement of charged particulate in two-phase flows, by summarizing the electrification mechanisms, physical models of particulate charging, and methods of charging/charged particulate entrained fluid flow simulations. Two effective methods can make droplets charged in industrial applications: corona charging and induction charging. The droplet charge to mass ratio by corona charging is more than induction discharge. The particle charging through collisions could be attributed to electron transfer, ion transfer, material transfer, and/or aqueous ion shift on particle surfaces. The charges on charged particulate surface can be measured, nevertheless, the charging process in nature or industry is difficult to monitor. The simulation method might build a bridge of investigating from the charging process to finally charged state on particulate surface in particulate entrained fluid flows. The methodology combining the interface tracking under the action of the applied electric with the fluid flow governing equations is applicable to the study of electrohydrodynamics problems. The charge

  13. [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]. (United States)

    Zhang, Zhi-Dan; Xi, Ben-Ye; Cao, Zhi-Guo; Jia, Li-Ming


    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.

  14. Measurement of particulate phase polycyclic aromatic hydrocarbon (PAHs) around a petroleum refinery. (United States)

    Rao, Padma S; Ansari, M Faiyaz; Pipalatkar, P; Kumar, A; Nema, P; Devotta, S


    A study on concentrations of ambient particulates viz. total suspended particulate matters (TSP), respirable suspended particulate matter (RSPM) and polycyclic aromatic hydrocarbons (PAH) were carried out at six sites around the Asia's largest, 12 MMTPA, petroleum refinery in west coast of India. PAH concentrations are correlated with each other in these sites, suggesting that they have related sources and sinks. The present article discusses the monitoring aspects such as sample collection, pretreatment and analytical methods and compares the monitored levels for assessing the source receptor distribution pattern. The main sources of RSPM and PAHs in urban air are automobile exhaust (CPCB, Polycyclic aromatic hydrocarbons (PAHs) in air and their effects on human health. " ", 2003; Manuel et al., Environmental Science and Technology, 13: 227-231, 2004) and industrial emissions like petroleum refinery (Vo-Dinh, Chemical analysis of polycyclic aromatic hydrocarbons, Wiley: New York, 1989; Wagrowaski and Hites, Environmental Science and Technology, 31: 279-282, 1997). Polycyclic aromatic hydrocarbons (PAH) are ubiquitous constituents of urban airborne particulate mostly generated by anthropogenic activities (Li et al., Environmental Science and Technology, 37:1958-2965, 2003; Thorsen et al., Environmental Science and Technology, 38: 2029-2037, 2004; Ohura et al., Environmental Science and Technology, 32: 450-455, 2004) and some of them are of major health concern mainly due to their well-known carcinogenic and mutagenic properties (Soclo et al., Marine Pollution Bulletin, 40: 387-396, 2000; Chen et al., Environment International, 28: 659-668, 2003; Larsen and Baker, Environmental Science and Technology, 32: 450-455, 2003). Limited information is available on PAHs contributions from refineries to ambient air. Hence this study would not only create a database but also provide necessary inputs towards dose-response relationship for

  15. The distribution of tritium between water and suspended matter in a laboratory experiment exposing sediment to tritiated water. (United States)

    Jean-Baptiste, Philippe; Fourré, Elise


    Following recent suggestions regarding the strong affinity of tritiated water for organic matter in suspended particulates and sediments, two equilibration experiments between sediment organic matter (dry and fresh) and tritiated water were performed to look for potential tritium bio-concentration. The T/H ratios measured at the end of both experiments are lower in the sediment organic matter than in the water, indicating that only a fraction of the hydrogen pool (between 14% and 20%) within the sediment equilibrated with the tritiated water. These results are consistent with the widely used concept of exchangeable and non-exchangeable tritium pools in organic matter and show no sign of tritium bio-accumulation in the sediment relative to water. Copyright © 2012 Elsevier Ltd. All rights reserved.

  16. 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


    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.

  17. 40 CFR Appendix B to Part 50 - Reference Method for the Determination of Suspended Particulate Matter in the Atmosphere (High... (United States)


    ... from this source be minimized by an automatic mechanical device that keeps the filter covered during...) 7.1.8 Pinholes: None. 7.1.9 Tear strength: 500 g minimum for 20 mm wide strip cut from filter in... divided by the inlet area measured in a horizontal plane at the lower edge of the cover. † Ideally, the...

  18. Turbulence control of floc size in suspended particulate matter (SPM) in the river estuary transition zone (RETZ) (United States)

    Jackson, Suzanna; Jago, Colin


    Quantifying floc properties in relation to physical forcings are key in determining the transfer flux of SPM from the catchment to the coastal ocean. Observations of floc development require high resolution data; in situ optical and acoustic instruments were deployed in the RETZ to obtain SPM and hydrodynamic properties. Results suggest that turbulent kinetic energy dissipation (TKE) can be correlated to median particle size (D50) and concentration on tidal and lunar time scales. Analysis on a tidal scale indicates terrestrially derived SPM and SPM of a marine origin display different relationships with the local turbulence regime, suggesting the D50 of terrestrially derived SPM is not limited to the eddy length scales of the Kolmogorov microscale. It is essential to improve methods to quantify the role of hydrodynamic processes in controlling SPM properties and thus the fate of the transfer of terrestrially derived organic matter to the coastal ocean.

  19. In situ produced branched glycerol dialkyl glycerol tetraethers in suspended particulate matter from the Yenisei River, Eastern Siberia

    NARCIS (Netherlands)

    De Jonge, C.; Stadnitskaia, A.; Hopmans, E.C.; Cherkashov, G.; Fedotov, A.; Sinninghe Damsté, J.


    Soil-derived branched glycerol dialkyl glycerol tetraethers (brGDGTs) in marine river fan sediments have a potential use for determining changes in the mean annual temperature (MAT) and pH of the river watershed soils. Prior to their incorporation in marine sediments, the compounds are transported

  20. 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.

    with low values during the monsoon, in spite of large terrestrial input, which can be attributed to microbial modification of terrestrial SPOM. A significant positive correlation of δ13C with salinity suggests the reliability of δ13C as a biogeochemical...