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1
Dreves, Alexander, Nils Andersen, Pieter M. Grootes, Marie-Josée Nadeau, and Carl-Dieter Garbe-Schönberg. "Colloidal matter in water extracts from forest soils." Environmental Chemistry 4, no. 6 (2007): 424. http://dx.doi.org/10.1071/en07057.
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Environmental context. Little is known about the proportion of tiny dispersed particles and true solutions in soil water although the distinction has a major influence on transport processes of organic matter, fertiliser and pollutants in soils and thus, e.g., on carbon storage, and its role in global warming. Our study has found a noticeable amount of tiny particles (range 17 nm to 1.0 μm) in filtered soil water, that have a different chemical composition and a lower bioavailability of their organic components in comparison to the soluble part. This significant occurrence and the ecological relevance of colloids for the transport and storage of soil constituents highlights the need to partition soil water content into ‘particulate’ and ‘dissolved’ since the access to soil pores determines particle transport. Abstract. Water-extracted organic matter (WEOM) is widely used as a surrogate for natural organic matter in soil water in the investigation of soil carbon dynamics. Information about the dissolved or colloidal nature of the organic matter is scarce since dissolved organic matter (DOM) is simply operationally defined by filtration: ‘DOM is what passes through the filter’. Water extracts of two topsoil horizons from both a deciduous (Steinkreuz) and a coniferous (Rotthalmünster) forest, located in Bavaria (Germany), were filtered through a 1-μm quartz filter and analysed regarding the amount of colloids in the range ~17 nm to 1.0 μm, the chemical composition and the radiocarbon concentration of both the colloidal and the dissolved fraction separated by high-speed centrifugation. Up to 13.9 wt-% of the total charge of the water extracts belongs to the colloidal fraction. The colloidal fraction has a higher relative proportion of metals and older organic C than the dissolved fraction. This demonstrates the dual nature of WEOM and the need for a more careful definition of DOM.
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Pokrovsky, O. S., L. S. Shirokova, S. N. Kirpotin, S. Audry, J. Viers, and B. Dupré. "Effect of permafrost thawing on organic carbon and trace element colloidal speciation in the thermokarst lakes of western Siberia." Biogeosciences 8, no. 3 (2011): 565–83. http://dx.doi.org/10.5194/bg-8-565-2011.
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Abstract. To examine the mechanisms of carbon mobilization and biodegradation during permafrost thawing and to establish a link between organic carbon (OC) and other chemical and microbiological parameters in forming thermokarst (thaw) lakes, we studied the biogeochemistry of OC and trace elements (TEs) in a chronosequence of small lakes that are being formed due to permafrost thawing in the northern part of western Siberia. Twenty lakes and small ponds of various sizes and ages were sampled for dissolved and colloidal organic carbon, metals and culturable heterotrophic bacterial cell number. We observed a sequence of ecosystems from peat thawing and palsa degradation due to permafrost subsidence in small ponds to large, km-size lakes that are subject to drainage to, finally, the khasyrey (drained lake) formation. There is a systematic evolution of both total dissolved and colloidal concentration of OC and TEs in the lake water along with the chronosequence of lake development that may be directly linked to the microbial mineralization of dissolved organic matter and the liberation of the inorganic components (Fe, Al, and TEs) from the organo-mineral colloids. In this chronosequence of lake development, we observed an apparent decrease in the relative proportion of low molecular weight <1 kDa (1 kDa ~ 1 nm) OC concentration along with a decrease in the concentration of total dissolved (<0.45 μm) OC. This decrease was accompanied by an increase in the small size organic ligands (probably autochthonous exometabolites produced by the phytoplankton) and a simultaneous decrease in the proportion of large-size organic (humic) complexes of allochthonous (soil) origin. This evolution may be due to the activity of heterotrophic bacterioplankton that use allochthonous organic matter and dissolved nutrients originating from peat lixiviation. Most insoluble TEs demonstrate a systematic decrease in concentration during filtration (5 μm, 0.45 μm) exhibiting a similar pattern among different samples. At the same time, there is an increase in the relative proportion of large size particles over the <1 kDa fraction for most insoluble elements along the chronosequence of lake evolution. TEs are likely to be bound to colloidal OC and coprecipitate with the mineral (Fe, Al) part of the colloids. Upon progressive consumption of dissolved OC by the heterotrophic bacteria, there is liberation of Fe, Al, and insoluble TEs in the water column that may be subjected to coagulation in the form of particles or large-size mineral colloids.
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Li, Yuan, Jie Liu, Yibiao Yu, Hao Zhu, Zheng Shen, and Yalei Zhang. "Particle Size Distribution Based Occurrence Features of Organic Components in Printing and Dyeing Wastewater Under a Treatment Process." E3S Web of Conferences 118 (2019): 04009. http://dx.doi.org/10.1051/e3sconf/201911804009.
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A more detailed occurrence features of organic matters in the printing and dyeing wastewater, based on its particle size distribution (PSD) and along with a wastewater treatment process, was conducted to provide a support for advanced treatment. Results suggested that, (1) In the dyeing wastewater, the occurrence characteristic of COD was: soluble>supra colloidal>colloidal>settleable; However, for protein, the supra colloidal was dominant, followed by the soluble. The feature of the polysaccharide was consistent with COD’s. In the wastewater, 29.66% of COD could be attributed to proteins and 3.45% of the COD could be attributed to polysaccharides. (2) The relationship among the forms of COD in the primary sedimentation tank, aerobic tank, secondary sedimentation tank, and reverse osmosis-treated concentrated effluent was consistent, that was: soluble>colloidal>supra colloidal>settleable. (3) In the primary sedimentation tank, the settleable COD was almost completely removed; In the aerobic tank, the residual super colloidal COD was not much; After MBR-RO treatment, the COD in the reverse osmosis concentrated water was almost dissolved and only a little presented in other forms.
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Tammelin, Tekla, Monika Österberg, and Ingvild A. Johnsen. "Adsorption of colloidal extractives and dissolved hemicelluloses on thermomechanical pulp fiber components studied by QCM-D." Nordic Pulp & Paper Research Journal 22, no. 1 (2007): 93–101. http://dx.doi.org/10.3183/npprj-2007-22-01-p093-101.
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Pokrovsky, O. S., L. S. Shirokova, J. Viers, et al. "Fate of colloids during estuarine mixing in the Arctic." Ocean Science 10, no. 1 (2014): 107–25. http://dx.doi.org/10.5194/os-10-107-2014.
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Abstract. The estuarine behavior of organic carbon (OC) and trace elements (TE) was studied for the largest European sub-Arctic river, which is the Severnaya Dvina; this river has a deltaic estuary covered in ice during several hydrological seasons: summer (July 2010, 2012) and winter (March 2009) baseflow, and the November–December 2011 ice-free period. Colloidal forms of OC and TE were assessed for three pore size cutoffs (1, 10, and 50 kDa) using an in situ dialysis procedure. Conventionally dissolved (< 0.22 μm) fractions demonstrated clear conservative behavior for Li, B, Na, Mg, K, Ca, Sr, Mo, Rb, Cs, and U during the mixing of freshwater with the White Sea; a significant (up to a factor of 10) concentration increase occurs with increases in salinity. Si and OC also displayed conservative behavior but with a pronounced decrease in concentration seawards. Rather conservative behavior, but with much smaller changes in concentration (variation within ±30%) over a full range of salinities, was observed for Ti, Ni, Cr, As, Co, Cu, Ga, Y, and heavy REE. Strong non-conservative behavior with coagulation/removal at low salinities (< 5‰) was exhibited by Fe, Al, Zr, Hf, and light REE. Finally, certain divalent metals exhibited non-conservative behavior with a concentration gain at low (~ 2–5‰, Ba, Mn) or intermediate (~ 10–15‰, Ba, Zn, Pb, Cd) salinities, which is most likely linked to TE desorption from suspended matter or sediment outflux. The most important result of this study is the elucidation of the behavior of the "truly" dissolved low molecular weight LMW< 1 kDa fraction containing Fe, OC, and a number of insoluble elements. The concentration of the LMW fraction either remains constant or increases its relative contribution to the overall dissolved (< 0.22 μm) pool as the salinity increases. Similarly, the relative proportion of colloidal (1 kDa–0.22 μm) pool for the OC and insoluble TE bound to ferric colloids systematically decreased seaward, with the largest decrease occurring at low (< 5‰) salinities. Overall, the observed decrease in the colloidal fraction may be related to the coagulation of organo-ferric colloids at the beginning of the mixing zone and therefore the replacement of the HMW1 kDa–0.22 μm portion by the LMW< 1 kDa fraction. These patterns are highly reproducible across different sampling seasons, suggesting significant enrichment of the mixing zone by the most labile (and potentially bioavailable) fraction of the OC, Fe and insoluble TE. The size fractionation of the colloidal material during estuarine mixing reflects a number of inorganic and biological processes, the relative contribution of which to element speciation varies depending on the hydrological stage and time of year. In particular, LMW< 1 kDa ligand production in the surface horizons of the mixing zone may be linked to heterotrophic mineralization of allochthonous DOM and/or photodestruction. Given the relatively low concentration of particulate versus dissolved load of most trace elements, desorption from the river suspended material was less pronounced than in other rivers in the world. As a result, the majority of dissolved components exhibited either conservative (OC and related elements such as divalent metals) or non-conservative, coagulation-controlled (Fe, Al, and insoluble TE associated with organo-ferric colloids) behavior. The climate warming at high latitudes is likely to intensify the production of LMW< 1 kDa organic ligands and the associated TE; therefore, the delivery of potentially bioavailable trace metal micronutrients from the land to the ocean may increase.
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Pokrovsky, O. S., L. S. Shirokova, J. Viers, et al. "Transformation of organic carbon, trace element, and organo-mineral colloids in the mixing zone of the largest European Arctic river." Ocean Science Discussions 10, no. 5 (2013): 1707–64. http://dx.doi.org/10.5194/osd-10-1707-2013.
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Abstract. The estuarine behavior of organic carbon (OC) and trace elements (TE) was studied for the largest European sub-Arctic river, which is the Severnaya Dvina; this river is a deltaic estuary covered in ice during several hydrological seasons: summer (July 2010, 2012) and winter (March 2009) baseflow, and the November–December 2011 ice-free period. Colloidal forms of OC and TE were assessed using three pore size cutoff (1, 10, and 50 kDa) using an in-situ dialysis procedure. Conventionally dissolved (< 0.22 μm) fractions demonstrated clear conservative behavior for Li, B, Na, Mg, K, Ca, Sr, Mo, Rb, Cs, and U during the mixing of freshwater with the White Sea; a significant (up to a factor of 10) concentration increase occurs with increases in salinity. Si and OC also displayed conservative behavior but with a pronounced decrease of concentration seawards. Rather conservative behavior, but with much smaller changes in concentration (variation within ±30%) over a full range of salinities, was observed for Ti, Ni, Cr, As, Co, Cu, Ga, Y, and heavy REE. Strong non-conservative behavior with coagulation/removal at low salinities (< 5‰) was exhibited by Fe, Al, Zr, Hf, and light REE. Finally, certain divalent metals exhibited non-conservative behavior with a concentration gain at low (~2–5‰, Ba, Mn) or intermediate (~10–15‰, Ba, Zn, Pb, Cd) salinities, which is most likely linked to TE desorption from suspended matter or sediment outflux. The most important result of this study is the elucidation of the behavior of the "truly" dissolved low molecular weight LMW< 1 kDa fraction containing Fe, OC, and a number of insoluble elements. The concentration of the LMW fraction either remains constant or increases its relative contribution to the overall dissolved (< 0.22 μm) pool as the salinity increases. Similarly, the relative proportion of colloidal (1 kDa–0.22 μm) pool for the OC and insoluble TE bound to ferric colloids systematically decreased seaward, with the largest decrease occurring at low (< 5‰) salinities. Overall, the observed decrease of the colloidal fraction may be related to the coagulation of organo-ferric colloids at the beginning of the mixing zone and therefore the replacement of the HMW1 kDa–0.22 μm portion by the LMW< 1 kDa fraction. These patterns are highly reproducible across different sampling seasons, suggesting significant enrichment of the mixing zone by the most labile (and potentially bioavailable) fraction of the OC, Fe and insoluble TE. The size fractionation of the colloidal material during estuarine mixing reflects a number of inorganic and biological processes, the relative contribution of which to element speciation varies depending on the hydrological stage and time of year. In particular, LMW< 1 kDa ligand production in the surface horizons of the mixing zone may be linked to heterotrophic mineralization of allochthonous DOM and/or photodestruction. Given the relatively low concentration of particulate vs. dissolved load of most trace elements, desorption from the river suspended material was less pronounced than in other rivers in the world. As a result, the majority of dissolved components exhibited either a conservative (OC and related elements such as divalent metals) or non-conservative, coagulation-controlled (Fe, Al, and insoluble TE associated with organo-ferric colloids) behavior. The climate warming in high latitudes is likely to intensify the production of LMW< 1 kDa organic ligands and the associated TE; therefore, the delivery of potentially bioavailable trace metal micronutrients from the land to the ocean may increase.
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Neal, C. "Rare earth element concentrations in dissolved and acid available particulate forms for eastern UK rivers." Hydrology and Earth System Sciences 11, no. 1 (2007): 313–27. http://dx.doi.org/10.5194/hess-11-313-2007.
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Abstract. Variations in concentration of yttrium (Y), lanthanum (La), cerium (Ce), neodymium (Nd), samarium (Sm) and gadolinium (Gd) among rivers of eastern England and the border with Scotland are described in relation to the dissolved (<0.45 µM) fraction and acid-available particulate (AAP) fractions. The rivers cover a range of rural, agricultural and urban/industrial environments. Yttrium and the lanthanides show significant levels of both dissolved and acid-available particulate forms (typically about 40% in the dissolved form). For the dissolved phase, Y and the lanthanides are linearly correlated with each other and with iron: most of this dissolved component may be in a micro-particulate/colloidal form. The Y and lanthanide relationships show marked scatter and there are anomalously high La concentrations at times for the rivers Great Ouse, Thames and Wear that are probably linked to pollutant sources. For the Ouse, and especially for one of its tributaries, the Swale, relatively high Sm concentrations are probably associated with mineralisation within the catchment and contamination of the associated flood plain. For the AAP components, there are strong linear relationships with Y and the lanthanides across all the rivers. There is also a strong link between these AAP associated REE and AAP iron, although the scatter is greater and the industrial rivers have a lower lanthanide to iron ratio, probably due to iron-rich contaminants.
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Leenheer, J. A. "Comprehensive assessment of precursors, diagenesis, and reactivity to water treatment of dissolved and colloidal organic matter." Water Supply 4, no. 4 (2004): 1–9. http://dx.doi.org/10.2166/ws.2004.0054.
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A comprehensive isolation, fractionation, and characterization research approach was developed for dissolved and colloidal organic matter (DOM) in water, and it was applied to various surface- and groundwaters to assess DOM precursors, DOM diagenesis, and DOM reactivity to water treatment processes. Major precursors for natural DOM are amino sugars, condensed tannins, and terpenoids. Amino sugar colloids derived from bacterial cell walls are incompletely removed by drinking water treatment and foul reverse osmosis membranes, but are nearly quantitatively removed by soil/aquifer treatment. When chlorinated, amino sugars produce low yields of regulated disinfection by-products (DBPs) but they produce significant chlorine demand that is likely caused by chlorination of free amino groups. Condensed tannins are major precursors for ,blackwater- DOM such as that found in the Suwannee River. This DOM produces high yields of DBPs upon chorination, and is efficiently removed by coagulation/flocculation treatment. Terpenoid-derived DOM appears to be biologically refractory, infiltrates readily into groundwater with little removal by soil/aquifer treatment, gives low DBP-yields upon chlorination and is poorly removed by coagulation/flocculation treatments. Peptides derived from proteins are major components of the base DOM fraction (10% or less of the mass of DOM), and this fraction produces large yields of haloacetonitriles upon chorination.
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Muller, François L. L. "Interactions of copper, lead and cadmium with the dissolved, colloidal and particulate components of estuarine and coastal waters." Marine Chemistry 52, no. 3-4 (1996): 245–68. http://dx.doi.org/10.1016/0304-4203(95)00097-6.
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Hwang, Byung-Gi, Kwan-Soo Jun, Young-Dae Lee, and Wu-Seng Lung. "Importance of DOC in sediments for contaminant transport modelling." Water Science and Technology 38, no. 11 (1998): 193–99. http://dx.doi.org/10.2166/wst.1998.0467.
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Contaminants in the interstitial waters are not only dissolved but also associated with a filterable colloidal phase such as DOC. The DOC plays an important role regulating the distribution of chemicals between particulate and dissolved phases since it binds chemicals and makes them unavailable for vertical diffusive exchange. A three-phase partitioning model that consists of free-dissolved, DOC-bound, particulate-bound components of the chemicals involved is used for the contaminant transport model in order to include the effect of DOC on the partition coefficient. The contaminant model is linked to WASP modeling framework to predict remobilization of PCBs in sediments and the fate and transport of the contaminant in overlying waters of the New Bedford Harbor where the harbor has been contaminated with PCBs and heavy metals released from electronic capacitor manufacturers. Simulation of remedial controls indicates that if no action is taken, PCB concentrations will continue to be at elevated levels. Several scenarios for the removal of contaminated sediments have been performed to reduce the elevated PCB concentrations to background levels.
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HAYNES, R. DANIEL. "Colloidal organic content and tackiness of coated broke and recycled fiber." TAPPI Journal 12, no. 7 (2013): 9–21. http://dx.doi.org/10.32964/tj12.7.9.
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The consistency, temperature and duration of repulping of coated broke and recycled fiber can determine the amount of colloidal organics liberated and the tackiness. In this study, old magazines, old newspapers, coated paper, envelopes, sticky notes, and office paper were repulped at differing consistency, temperature, and duration. The colloidal and dissolved organic content was measured along with the tackiness of each pulping condition to better understand the stickies and white pitch released. This understanding of released colloidal stickies and colloidal white pitch during repulping treatment by means of fixative was applied to an examination of stabilizers and detackifiers to determine best means of control. This work developed a tackiness scale for typical furnish used in recycling to help understand the tackiness associated with adhesives (envelopes and sticky notes) and paper additives (office paper, old magazines, and coated paper) compared to old newspapers and to recycled lap pulp. The study found that the adhesive-containing papers (envelopes and sticky notes) is 4–10 times tackier than old magazines and really is not comparable when considering old newspapers. Compared to recycle lap pulp, adhesive-contaminated paper is 50–150 times tackier and coated paper is 15–50 times tackier than recycle lap pulp. The evaluation shows that more tacky components are released during pulping at higher temperatures and lower consistencies.
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Scherrenberg, S. M., A. F. van Nieuwenhuijzen, H. W. H. Menkveld, J. J. M. den Elzen, and J. H. J. M. van der Graaf. "Innovative phosphorus distribution method to achieve advanced chemical phosphorus removal." Water Science and Technology 58, no. 9 (2008): 1727–33. http://dx.doi.org/10.2166/wst.2008.535.
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Since November 2006 a large-scale research project has been carried out at Wastewater Treatment Plant (WWTP) Leiden Zuidwest (within the Rijnland District Water Control Board). This research focuses on advanced removal of nutrients (phosphorus and nitrogen), heavy metals and priority hazardous substances from WWTP-effluent with different treatment techniques to reach an effluent quality, which could be required in the future by the Water Framework Directive (WFD) 2000/60/EC. Within the WFD-approach to guarantee an ecological and a chemical “good status” of the receiving water bodies, the focus is more and more on ultra low phosphorus concentrations in effluent. To be able to reach these stringent goals more insight into phosphorus components in effluent is required. A new method of distribution of phosphorus is used to determine orthophosphate, metal bound phosphorus, dissolved “organic” phosphorus and particulate “organic” phosphorus. This knowledge about the distribution of phosphorus makes it possible to compare different filter concepts and different process parameters, for example flocculation time, initial mixing energy and filtration rates. When comparing (filter concept 1) continuous sand filtration with (filter concept 2) dual media filtration for phosphorus removal, it appears that, a higher percentage of the formed metal bound phosphorus will pass the continuous sand filter. The ortho-phosphorus which is not bound to trivalent metal after coagulation will remain dissolved ortho-phosphorus and will pass the filter bed. This is shown in both filter concepts. The dissolved ‘organic’ phosphorus decreases after flocculation and the particulate ‘organic’ phosphorus increases which suggests that it may be colloidal or associated with colloidal material. With continuous sand filtration 50% of the particulate phosphorus is removed. In the dual media filter even 86% of the particulate phosphorus is removed.
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Gfeller, Lorenz, Andrea Weber, Isabelle Worms, Vera I. Slaveykova, and Adrien Mestrot. "Mercury mobility, colloid formation and methylation in a polluted Fluvisol as affected by manure application and flooding–draining cycle." Biogeosciences 18, no. 11 (2021): 3445–65. http://dx.doi.org/10.5194/bg-18-3445-2021.
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Abstract. Floodplain soils polluted with high levels of mercury (Hg) are potential point sources to downstream ecosystems. Repeated flooding (e.g., redox cycling) and agricultural activities (e.g., organic matter addition) may influence the fate and speciation of Hg in these soil systems. The formation and aggregation of colloids and particles influence both Hg mobility and its bioavailability to microbes that form methylmercury (MeHg). In this study, we conducted a microcosm flooding–draining experiment on Hg-polluted floodplain soils originating from an agriculturally used area situated in the Rhone Valley (Valais, Switzerland). The experiment comprised two 14 d flooding periods separated by one 14 d draining period. The effect of freshly added natural organic matter on Hg dynamics was assessed by adding liquid cow manure (+MNR) to two soils characterized by different Hg (47.3±0.5 or 2.38±0.01 mg kg−1) and organic carbon (OC: 1.92 wt % or 3.45 wt %) contents. During the experiment, the release, colloid formation of Hg in soil solution and net MeHg production in the soil were monitored. Upon manure addition in the highly polluted soil (lower OC), an accelerated release of Hg to the soil solution could be linked to a fast reductive dissolution of Mn oxides. The manure treatments showed a fast sequestration of Hg and a higher percentage of Hg bound by particulate (0.02–10 µm). Also, analyses of soil solutions by asymmetrical flow field-flow fractionation coupled with inductively coupled plasma mass spectrometry (AF4–ICP–MS) revealed a relative increase in colloidal Hg bound to dissolved organic matter (Hg–DOM) and inorganic colloidal Hg (70 %–100 %) upon manure addition. Our experiment shows a net MeHg production the first flooding and draining period and a subsequent decrease in absolute MeHg concentrations after the second flooding period. Manure addition did not change net MeHg production significantly in the incubated soils. The results of this study suggest that manure addition may promote Hg sequestration by Hg complexation on large organic matter components and the formation and aggregation of inorganic HgS(s) colloids in Hg-polluted Fluvisols with low levels of natural organic matter.
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Dulaquais, Gabriel, Matthieu Waeles, Johann Breitenstein, Joël Knoery, and Ricardo Riso. "Links between size fractionation, chemical speciation of dissolved copper and chemical speciation of dissolved organic matter in the Loire estuary." Environmental Chemistry 17, no. 5 (2020): 385. http://dx.doi.org/10.1071/en19137.
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Environmental contextThe toxicity of copper to aquatic life is highly dependent on its chemical form. In the vineyards of the Loire valley, mixtures of copper compounds are increasingly being used as fungicides. Our study investigating the origin and behaviour of dissolved copper on the land-sea continuum of the Loire advances our understanding of the chemical forms and fate of copper in estuarine systems. AbstractWe present data on the organic speciation of dissolved copper (dCu) in the Loire estuary for the soluble (&lt;0.02µm) and dissolved (&lt;0.45µm) fractions. These results were interpreted according to the distribution of natural organic matter along the estuary. We observed a high concentration of dCu (80nmolkg−1) upstream of the tidal front (S=0.1, where S is the salinity), possibly induced by drainage from vineyards located on the watershed of the estuary, and a concentration typical of coastal seawater at the end of the salinity gradient (3–4nmolkg−1). dCu showed a non-conservative distribution along the estuary with a notably strong decrease in concentration at the very first stage of mixing (S ~ 0.5) that increased again at low salinity (S=4.7). The latter increase in the concentration of dCu was related to the supply of colloidal copper induced by particle desorption in the maximum turbidity zone. The organic speciation of dCu revealed that the complexing capacity of copper ligands (LCu, up to 147 nanomoles of Cu per kilogram of water) exceeded dCu in both the soluble and dissolved fractions, which kept the activity of cupric ions below toxic levels for most unicellular phytoplankton. Humic substances comprised up to 95% of LCu in the continental shelf sample, but their complexing capacity did not account for all of the LCu in the inner estuary. We conducted pseudopolarographic experiments and found two other additional ligand classes: thiol-like and amino-acids/proteins. While humic substances are the dominant component of dissolved organic matter (DOM), the study of DOM suggested the release of colloidal DOM from a wastewater treatment plant. This structure could be a major source of proteinaceous LCu in the system that changes the dCu speciation in the middle of the estuary.
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Middelboe, Mathias, and Niels O. G. Jørgensen. "Viral lysis of bacteria: an important source of dissolved amino acids and cell wall compounds." Journal of the Marine Biological Association of the United Kingdom 86, no. 3 (2006): 605–12. http://dx.doi.org/10.1017/s0025315406013518.
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Viral infection of bacteria causes release of dissolved organic matter (DOM), which is available for bacterial uptake. In aquatic environments, this virus-mediated transformation of living cells into dissolved and colloidal organic matter may be a quantitatively important process in the pelagic recycling of carbon and nutrients, but little is known about the amount, composition, or bioavailability of viral lysates. By using a model system of a marine bacterium (Cellulophaga sp.) and a virus specific to this bacterium, the present study provides a first quantification of the input of dissolved free and combined amino acids (DFAA and DCAA) and bacterial cell wall compounds following viral lysis. The DCAA constituted 51–86% of the total virus-mediated organic carbon release of 1087–1825 μg C l−1 (estimated biomass of the lysed bacteria), whereas DFAA and glucosamine each accounted for 2–3% of total lysate-C. The viral particles themselves constituted 4–6% of the released organic carbon, and altogether, the applied analyses thus identified 53–92% of the released lysates. Approximately 12% of the identified compounds were derived from bacterial cell wall peptidoglycan, including various D-isomers of DFAA and DCAA, glucosamine and diaminopimelic acid (DAPA). Although a portion of this cell wall material may have entered the pool of refractory material, a significant fraction of some peptidoglycan-derived components, e.g. 83% of the released D-DFAA, were removed from the dissolved phase during the last part of the incubations, suggesting that part of the cell wall material were utilized by the developing virus-resistant Cellulophaga population. Therefore, we suggest that virus-mediated DOM is a source of a variety of organic compounds, which contribute significantly to the pool of rapidly recycling material in the ocean.
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Shevchenko, Vladimir P., Oleg S. Pokrovsky, Sergey N. Vorobyev, et al. "Impact of snow deposition on major and trace element concentrations and elementary fluxes in surface waters of the Western Siberian Lowland across a 1700 km latitudinal gradient." Hydrology and Earth System Sciences 21, no. 11 (2017): 5725–46. http://dx.doi.org/10.5194/hess-21-5725-2017.
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Abstract. In order to better understand the chemical composition of snow and its impact on surface water hydrochemistry in the poorly studied Western Siberia Lowland (WSL), the surface layer of snow was sampled in February 2014 across a 1700 km latitudinal gradient (ca. 56.5 to 68° N). We aimed at assessing the latitudinal effect on both dissolved and particulate forms of elements in snow and quantifying the impact of atmospheric input to element storage and export fluxes in inland waters of the WSL. The concentration of dissolved+colloidal (< 0.45 µm) Fe, Co, Cu, As and La increased by a factor of 2 to 5 north of 63° N compared to southern regions. The pH and dissolved Ca, Mg, Sr, Mo and U in snow water increased with the rise in concentrations of particulate fraction (PF). Principal component analyses of major and trace element concentrations in both dissolved and particulate fractions revealed two factors not linked to the latitude. A hierarchical cluster analysis yielded several groups of elements that originated from alumino-silicate mineral matrix, carbonate minerals and marine aerosols or belonging to volatile atmospheric heavy metals, labile elements from weatherable minerals and nutrients. The main sources of mineral components in PF are desert and semi-desert regions of central Asia. The snow water concentrations of DIC, Cl, SO4, Mg, Ca, Cr, Co, Ni, Cu, Mo, Cd, Sb, Cs, W, Pb and U exceeded or were comparable with springtime concentrations in thermokarst lakes of the permafrost-affected WSL zone. The springtime river fluxes of DIC, Cl, SO4, Na, Mg, Ca, Rb, Cs, metals (Cr, Co, Ni, Cu, Zn, Cd, Pb), metalloids (As, Sb), Mo and U in the discontinuous to continuous permafrost zone (64–68° N) can be explained solely by melting of accumulated snow. The impact of snow deposition on riverine fluxes of elements strongly increased northward, in discontinuous and continuous permafrost zones of frozen peat bogs. This was consistent with the decrease in the impact of rock lithology on river chemical composition in the permafrost zone of the WSL, relative to the permafrost-free regions. Therefore, the present study demonstrates significant and previously underestimated atmospheric input of many major and trace elements to their riverine fluxes during spring floods. A broader impact of this result is that current estimations of river water fluxes response to climate warming in high latitudes may be unwarranted without detailed analysis of winter precipitation.
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Savenko, A. V., and O. S. Pokrovsky. "Distribution of dissolved matter in the Yenisei river estuary and adjacent water area of the Kara sea and its interannual variability." Геохимия 64, no. 11 (2019): 1175–86. http://dx.doi.org/10.31857/s0016-752564111175-1186.
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The distribution of dissolved matter (major ions, nutrients, and trace elements) in the Yenisei River estuary and adjacent water area was studied according to the natural observations data from 20092016. These results were compared to the literature data of hydrochemical researches of this region. It was shown that transport of major ions (Na, K, Mg, Ca, SO4) and some trace elements (Li, Rb, Cs, Sr, B, F, Cr, Ge, As, Mo, U) is described by the stable in the long-term period equations of conservative mixing between riverine and seawater masses. Alkalinity also belongs to conservative components; however this parameter exhibits substantial spatiotemporal variability of the distribution caused by complex hydrological structure of the Yenisei Bay and adjoining part of the Kara Sea. Concentrations of Pmin, Si, and V in the desalinized waters of photic layer decreases seaward during vegetation period owing to uptake by phytoplankton. The losses of these elements reach 3057, 30, and 9% of their supply by river runoff, respectively. The content of dissolved Pmin and V in the intermediate and near-bottom layers of the Yenisei River estuary strongly increases with increase of salinity due to regeneration of precipitated organic matter, whereas silica remineralization is much less pronounced. Barium in the all estuary is intensively desorbed from river suspended matter in the quantity reaching 20100% of its dissolved forms input with river runoff depending on seasonal variations of chemical composition of the last. The transport of dissolved forms of heavy metals (Mn, Fe, Pb) and elements-hydrolyzates (Al, Ti, Y, La, Ce, Pr) in the mixing zone between the riverine and seawater masses is probably controlled by the coagulation and flocculation of organic and organomineral colloids, which is indicated by decrease in the concentrations of these elements at the beginning of salinization (for 2061%) with subsequent approximation to the seawater mass characteristics.
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Cuthill, Holly, Carole Elleman, Thomas Curwen, and Bettina Wolf. "Colloidal Particles for Pickering Emulsion Stabilization Prepared via Antisolvent Precipitation of Lignin-Rich Cocoa Shell Extract." Foods 10, no. 2 (2021): 371. http://dx.doi.org/10.3390/foods10020371.
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This study concerns the preparation and functionality testing of a new class of Pickering particles for food emulsion stabilization: colloidal lignin-rich particles (CLRPs) derived from ethanol-soluble extract of cocoa shell. A further goal was to achieve Pickering functionality without the need to add co-emulsifying surfactants during emulsion processing. Cocoa shell is a co-product of the food manufacturing industry. As such it is anticipated that the particles would be accepted as a natural food ingredient, provided no harmful solvents are used in any step of their processing. The cocoa shell particles were milled, dispersed in water and exposed to 250 °C for 1 h in a stainless-steel tubular reactor followed by ethanol extraction to obtain a lignin-rich extract (46% (w/w) lignin with the remainder predominantly lipids). CLRPs were then fabricated by the precipitation of ethanol-dissolved extract into water (antisolvent). By employing an agitated process and droplet dosing into a non-agitated process, four particle suspensions of a range of submicron diameters were obtained. All particle suspensions contained the same mass fraction of extract and were surface active, with surface tension decreasing with increasing particle size. The smallest particles were obtained when lipids were removed from the extract prior to particle processing. In contrast to the other four particle suspensions, this one failed to stabilize a 10% (w/w) sunflower oil-in-water emulsion. We hypothesize that the phospholipids indigenously present in these CLRP formulations are a critical component for Pickering functionality. It can be concluded that we have successfully introduced a new class of Pickering particles, fabricated from an industry co-product and anticipated to be food grade.
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Sablii, Larysa, Veronika Zhukova, and Lyudmyla Yepishova. "Problems of previous local treatment wastewater of oil production and their effective solution." Problems of Water supply, Sewerage and Hydraulic, no. 35 (May 31, 2021): 48–55. http://dx.doi.org/10.32347/2524-0021.2021.35.48-55.
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The technology of local wastewater treatment of oil production is presented. It based on the consistent use of physico-chemical treatment methods and allows to remove organic matter, suspended solids from wastewater to the requirements of regulations and divert treated wastewater into the municipal sewerage system. Wastewater generated during the processing of soapstocks, in terms of pollutants exceeds the standards set for wastewater when discharged into urban drainage systems. Therefore, before removal to municipal treatment facilities, they must be treated locally using physico-chemical and biological methods. In the phase-dispersed state, such wastewater is a stable emulsion. The presence of phospholipids, which are stabilizers of emulsions, complicates the phase separation of wastewater components. In addition, wastewater contains suspended particles, colloidal and dissolved substances of organic and inorganic nature. It was found that the highest values of the effect of removal of organic matter by COD - 78% at the initial COD - 40000 mg / dm3, the effect of reducing the concentration of suspended solids - 72.5% at the initial 6300 mg / dm3 were obtained in the process of coagulation using Al2 (SO4)3 and subsequent flotation with air supply through porous materials. The technological scheme of local treatment of industrial wastewater is proposed. It includes the following main processes: averaging, aeration, alkalinization, coagulation, flotation, oxidation, filtration, adsorption. Experimental studies have shown the effectiveness of treatment of soapstocks in oil production using the proposed technology with bringing the quality of treated wastewater to current sanitary requirements, which allowed to recommend the technology of treatment of soapstocks for successful use in industrial enterprises of the oil industry.
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Habets, Leo H. A., and Heins J. Knelissen. "In line biological water regeneration in a zero discharge recycle paper mill." Water Science and Technology 35, no. 2-3 (1997): 41–48. http://dx.doi.org/10.2166/wst.1997.0478.
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The recycled paper group of KNP-BT operates in total 12 paper and board mills in Western Europe. All together the output of recycled product is 1.5 million tpy, of which approx. 50% is testliner and corrugated medium. The company has been a pioneer in process water closure for more than 20 years and several of its mills were already operating totally effluent free, long before the term “zero effluent” was invented. Some advantages of this way of operation are energy conservation and no charges for effluent discharge. Disadvantages are amongst others, accumulation of organic compounds, increased salt content, water hardness and volatile fatty acid build up. One of the fluting and testliner mills in the group is Zülpich Papier, which is currently going through an extension phase from 170.000 tpy to 340.000 tpy. This particular mill has been operated under complete effluent free circumstances almost 20 years. However, even though the new machine is to be put into operation in October 1996, a biological process water regeneration plant has been put on stream already in September 1995 in order to collect experience with the internal treatment and to have everything running smoothly by the time the new machine is started. The in line treatment consists of an anaerobic and an aerobic stage. During the first stage the dissolved organic components like carbohydrates and volatile fatty acids are converted into methane gas. At the same time, sulphate reducing bacteria convert sulphate into hydrogen sulphide, which is stripped out by the biogas. During the subsequent aerobic stage, residual organic components are oxidized into carbonate, which precipitates with calcium ions into the aerobic sludge and accumulates as calcium carbonate. These are a few examples of what is being achieved. Due to several favourable reactions in the biological stage, the process water quality has improved drastically for the following criteria: Odour, corrosion properties, salt content (conductivity), hardness, viscosity, COD-level and pH. Also components like stickies, waxes and colloidal material are presumably being degraded during the biological regeneration process. In the paper a description is given of the plant, as well as an overview of the main improvements of the process water quality during the first four months of in line biological treatment.
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Borgne, François Le, Michel Treuil, Jean-Louis Joron, and Michel Lepiller. "Natural and EDTA-complexed lanthanides used as a geochemical probe for aquifers: a case study of Orleans valley’s alluvial and karstic aquifers." Bulletin de la Société Géologique de France 176, no. 6 (2005): 513–29. http://dx.doi.org/10.2113/176.6.513.
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Abstract The transit of chemical elements within the different parts of Orleans valley’s aquifer is studied by two complementary methods. Those methods rely on the fractionation of lanthanides (Ln) during their migration in natural waters. The first method consists in studying natural lanthanides patterns within the watershed, at its entries and exits. The second one lies on multi-tracer experiments with Ln-EDTA complexes. This work is completed through an observation network consisting of 52 piezometers set on a sand and gravel quarry, and the natural entries and exits of the aquifer. Orleans valley’s aquifer, which is made of an alluvial watershed lying on a karstic aquifer, is mainly fed by the Loire river via a large karstic network. At the entries of the aquifer (Loire river at Jargeau), the Ln concentrations in the dissolved fraction (&lt; 0,22 μm) vary with the flow of the river. During floods, Loire river waters display bulk continental crust-like Ln compositions with a slight enrichment in heavy Ln from Dy to Lu. When the Loire river flow becomes low level, the crust-normalised Ln patterns show a depletion in light Ln whereas Lu concentrations remain identical. The same evolution spatially occurs between the entries and exits of the karstic network. Spring waters are depleted in light Ln relative to the Loire river whereas heavy Ln (Yb, Lu) remain constant during transit. Furthermore, the depletion in light Ln increases with the distance between entries and exits. Tracer experiments using EDTA-complexed Ln within and between the alluvial and calcareous parts of the watershed have shown that complexed Ln are fractionated across all these geological strata. The recoveries of tracers always follow the order light Ln &lt; heavy Ln. Moreover, both sediments analyses and filtering experiments at a porosity of 0,02 μm show that, in the presence of EDTA, Ln adsorb onto sediments and colloids in the order light Ln &gt; heavy Ln. On the other hand, the filtration of alluvial groundwater with high colloids content induces no significant Ln fractionation when the solution contains no strong chelating agent. Hence, the transit of natural and artificial Ln in Orleans valley aquifer can be explained by two complementary processes. (1) Decanting/filtering or, on the opposite, stirring of colloids. Those processes induce no important Ln fractionation. (2) Exchanges of Ln between solute complexes, colloids and sediments due to the presence of strong chelating agents. Those exchanges fractionate the Ln in the order of their stability constants. Considering the natural Ln fractionation that occurs in the Loire river and in the studied aquifer, the carbonates, the stability constants of which follow the order light Ln &lt; heavy Ln, are the best candidates as natural strong chelating agents. From the hydrodynamic point of view, both tracer experiments and natural Ln concentrations show that the transfer of elements within the alluvial watershed is pulsed by the Loire river movements. During an ascent phase, the elements migrate away from and perpendicularly to the karstic channels direction. During the river descent, horizontal flows are quasi absent and migrations are mainly vertical from the alluvia down to the calcareous part of the aquifer. Due to those hydrodynamic characteristics, alluvia and non fissured limestone have a high dynamic confining capacity. Elements with high affinity for solid or colloidal phases (e.g. light Ln) have an increased confining capacity in the whole aquifer, by sorption and colloid filtration within the alluvia and at the alluvial-calcareous interface, and by colloid decanting within the karstic channels. Overall, this model combines two components. The first one, hydrodynamical, results from the repartition of the loads pulsed by river Loire through the karst. The second one physico-chemical, results from the element distribution mainly controlled by colloïde/solute complexes exchange coefficients.
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Schuwerack, P. M. M., M. Neal, and C. Neal. "The Dart estuary, Devon, UK: a case study of chemical dynamics and pollutant mobility." Hydrology and Earth System Sciences 11, no. 1 (2007): 382–98. http://dx.doi.org/10.5194/hess-11-382-2007.
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Abstract. Water, sediments and gill and digestive gland tissues of adult common shore crab (Carcinus maenas), collected at Noss Marina, Sandquay (Britannia Royal Naval College), the Dartmouth Pier, Warfleet Cove and Sugary Cove in the Dart estuary, Devon, UK, were analysed for major, minor and trace elements in spring 2004. Total acid-available measurements analysed included the truly dissolved component and acid-available sediments. Trace metal concentrations are associated largely with particulate and micro-particulate/colloidal phases, the latter being able to pass through standard filter papers. Wide ranges of chemical concentrations were found in the water, sediments and tissues at all the locations. In the water column, 48% of the variance is linked to the sea-salt component (Cl, Na, K, Ca, Mg, B, Li and Sr) and the sediment-associated acid-available fractions are linked to Fe-rich lithogenous materials (Ba, Co, Cu, Fe, Mn, V and Zn). In the sediments, trace elements of Cd, Co, Cr, Fe, Pb, Mn, Ni and V are correlated with the sea salts and associated with the fraction of fine sediments within the total sediment. In the gills and the digestive gland tissues of crabs, high concentrations of Al, Cu and Fe are found and there are correlations between acid-available trace metals of Cu, Cr, Fe, Mn, Ni, Sr and Zn. The relationships between trace metal contaminants, their site-specific concentrations, their temporal and spatial variability and the effects of human activities, such as moorland/agriculture with historic mining and recreational activities in the lower Dart estuary, are discussed.
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Gaboury, Damien. "The Neglected Involvement of Organic Matter in Forming Large and Rich Hydrothermal Orogenic Gold Deposits." Geosciences 11, no. 8 (2021): 344. http://dx.doi.org/10.3390/geosciences11080344.
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Orogenic gold deposits have provided most of gold to humanity. These deposits were formed by fluids carrying dissolved gold at temperatures of 200–500 °C and at crustal depths of 4–12 km. The model involves gold mobilization as HS− complexes in aqueous solution buffered by CO2, with gold precipitation following changes in pH, redox activity (fO2), or H2S activity. In this contribution, the involvement of carbonaceous organic matter is addressed by considering the formation of large and/or rich orogenic gold deposits in three stages: the source of gold, its solubilization, and its precipitation. First, gold accumulates in nodular pyrite within carbonaceous-rich sedimentary rocks formed by bacterial reduction of sulfates in seawater in black shales. Second, gold can be transported as hydrocarbon-metal complexes and colloidal gold nanoparticles for which the hydrocarbons can be generated from the thermal maturation of gold-bearing black shales or from abiotic origin. The capacity of hydrocarbons for solubilizing gold is greater than those of aqueous fluids. Third, gold can be precipitated efficiently with graphite derived from fluids containing hydrocarbons or by reducing organic-rich rocks. Black shales are thus a key component in the formation of large and rich orogenic gold deposits from the standpoints of source, transport, and precipitation. Unusual CO2-rich, H2O-poor fluids are documented for some of the largest and richest orogenic gold deposits, regardless of their age. These fluids are interpreted to result from chemical reactions involving hydrocarbon degradation, hence supporting the fundamental role of organic matter in forming exceptional orogenic gold deposits.
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Zhang, Hao, and William Davison. "Use of diffusive gradients in thin-films for studies of chemical speciation and bioavailability." Environmental Chemistry 12, no. 2 (2015): 85. http://dx.doi.org/10.1071/en14105.
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Environmental context The health of aquatic organisms depends on the distribution of the dissolved forms of chemical components (speciation) and their rates of interaction (dynamics). This review documents and explains progress made using the dynamic technique of diffusive gradients in thin-films (DGT) to meet these challenges of measuring directly chemical speciation and associated dynamics in natural waters. The relevance of these measurements to uptake by biota of chemical forms in soils, sediments and water is discussed with reference to this expanding literature. Abstract This review assesses progress in studies of chemical speciation using diffusive gradients in thin-films (DGT) by examining the contributions made by key publications in the last 20 years. The theoretical appreciation of the dynamic solution components measured by DGT has provided an understanding of how DGT measures most metal complexes, but excludes most colloids. These findings strengthen the use of DGT as a monitoring tool and provide a framework for using DGT to obtain in situ kinetic information. Generally, the capabilities of DGT as an in situ perturbation and measurement tool have yet to be fully exploited. Studies that have used DGT to investigate processes relevant to bioavailability have blossomed in the last 10 years, especially for soils, as DGT mimics the diffusion limiting uptake conditions that, under some conditions, characterise uptake by plants. As relationships between element accumulated by DGT and in plants depend on the plant species, soils studied, and the element and its chemical form, DGT is not an infallible predictive tool. Rather its strength comes from providing information on the labile species in the system, whether water, soil or sediment. Recent studies have shown good relationships between measurements of metals in periphyton and by DGT, and unified dose response curves have been obtained for biota in sediments when they are based on DGT measurements. Both these cases suggest that alternative approaches to the established ‘free ion’ approach may be fruitful in these media and illustrate the growing use of DGT to investigate environmental chemical processes.
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Kriho, V., B. Wagner, E. G. Erdos, and R. P. Becker. "Immunogold labelling of neutral endopeptidase 24.11 (enkephalinase), on human neutrophils and neutrophil cytoplasts." Proceedings, annual meeting, Electron Microscopy Society of America 47 (August 6, 1989): 920–21. http://dx.doi.org/10.1017/s0424820100156584.
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We have documented the presence of neutral endopeptidase 24.11 (NEP), on the surface of human neutrophils (PMN) and PMN cytoplasts. Cytoplasts are whole cell preparations which contain cytomatrix, but lack internal membranes and organelles ,such as nuclei and lysosomal granules. These structures have been extracted mechanically, leaving the plasma membrane “outside-out” topology intact. Cytoplasts are very useful in correlative studies of cell surface structure and function. Biochemically, the membrane component of cytoplasts is predominantly plasma membrane; structurally, chemical activity may be localized to domains of the intact cell surface. NEP is a membrane-bound metalloendopeptidase present in human PMN' s. We have marked NEP on the plasma membranes of PMNs and PMN cytoplasts via pre-embedding iramunocytochemistry. We used scanning electron microscopy (SEM) with backscattered electron imaging (BEI) to visualize Au labelled anti-NEP on the surface of a large number of cells. Transmission electron microscopy (TEM) was used to confirm the presence of the enzyme on PMN's and PMN cytoplasts.Suspensions of PMN or PMN cytoplasts (2 x 106 cells/ml) were fixed for 8 min at room temp. in 0.25% glutaraldehyde in phosphate buffered saline (PBS) pH 7.2 rinsed in PBS, treated with 0.1% glycine in PBS for 10 rain and then incubated for 15 min in 5% normal goat serum (NGS) in 0.1% bovine serum albumin dissolved in PBS (BSA/PBS). Following this step, cells were incubated for 20 min in anti- NEP antibody, rinsed in BSA/PBS, incubated in goat anti-rabbit IgG coupled to 15nm colloidal Au particles (GARG15) for 1 h and again rinsed in PBS. Postfixation for 30 min in 2.5% glutaraldehyde and PBS rinsing followed. For SEM a drop of cell suspension was put on a polylysine- treated Formvar-carbon-coated Au grid and cells were allowed to settle and attach for 30 min. The grid was rinsed in water, dehydrated and critical point dried. Cells were coated with carbon before viewing by SEM. For TEM, following immunolabelling, cells were post-fixed in OsO4, rinsed, dehydrated and embedded in Epon for sectioning.
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Li, Zongquan, Qin Liu, Jiansong Chen, and Yingjuan Fu. "Enhancement of colloidal particle and lignin removal from pre-hydrolysis liquor by pectinase pre-treatment – Study on model substances." BioResources 14, no. 1 (2018): 409–20. http://dx.doi.org/10.15376/biores.14.1.409-420.
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Removal of colloidal particle and lignin from pre-hydrolysis liquor (PHL) is important for the subsequent processing and utilization of the saccharides in the PHL. Cationic polymers treatment is a common method for the purpose, and pectinase pre-treatment of PHL can improve the efficiency of the treatment with cationic polymers. To investigate the mechanism of pectinase pre-treatment for improvement of the cationic polymer efficiency, polygalacturonic acid (PGA) was added in the colloidal lignin and dissolved lignin model substances systems, respectively, and the effects of polygalacturonic acid (PGA) and its pectinase pre-treatment on the removal of colloidal and dissolved lignin in the following cationic polymer treatment process were studied. The results showed that the presence of PGA caused the increase of negative charge density of the colloidal lignin and dissolved lignin systems, which lowered the efficiency of the cationic polymers and negatively affected the removal of both the colloidal lignin and the dissolved lignin. After pectinase treatment, the PGA present in the colloidal and dissolved lignin system was degraded and the negative effects on the cationic polymers were eliminated, and the efficiency of the cationic polymers was improved. Compared to the colloidal lignin and dissolved lignin systems with PGA, less cationic polymers were needed for the same systems with pectinase treatment to obtain the similar lignin removal level.
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Liu, Hui, Meiling Li, Kaili Zhu, et al. "Analysis of dissolved and colloidal substances in old corrugated containers’ whitewater and dissolved substances’ impact on colloidal substances’ stability." BioResources 15, no. 3 (2020): 6668–79. http://dx.doi.org/10.15376/biores.15.3.6668-6679.
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The physicochemical properties of dissolved and colloidal substances (DCS) in the old corrugated containers’ (OCC) whitewater were studied. Then, the colloidal substances (CS) were separated from dissolved substances (DS) and the effect of inorganic salts on the stability of CS (not DCS) was studied for the first time. The results showed that many DCS aggregated and attached to the fiber surface when pulping. The primary sources were resin, lignin, adhesives, coating fixatives, and fillers. The colloidal stability of DCS and solids of whitewater differed because the DCS contained less filler. Both Ca2+ and Na+ can affect the stability of CS, but Ca2+ led to more CS instability and aggregated into larger flocculent precipitates. The surprising discovery in the experiment was that when Ca2+ and Na+ were added together, the instability degree of the system was between the addition of Ca2+ and Na+ alone. Ca2+ played a dominant role in affecting the stability of CS, and Na+ competed for adsorption sites.
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Deein, G., W. Thimdee, and K. Matsunaga. "Bioavailable colloidal iron in river water originated from the forest." Marine and Freshwater Research 53, no. 1 (2002): 43. http://dx.doi.org/10.1071/mf00145.
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In samples of water from five sites on the Shukunohe, Ohno and Kunebetsu rivers, Japan, most of the filterable iron (<0.45 m) was colloidal iron (0.45–0.025 m). There was a correlation between dissolved iron and colloidal iron; both are assumed to be associated with humic substances, since the carbon isotope ratio of colloidal organic substances on glass-fibre filters corresponded to the ratio of mountain humic soil. In culture experiments, the freshwater phytoplankton Melosira granulata var. angustissima f. spiralis grew rapidly in a medium containing colloidal iron, to a maximum of ~250 000 cells mL–1. However, there was little growth with amorphous colloidal iron and no growth in control medium containing ~0.1 M dissolved Fe. In a multispecies phytoplankton culture, colloidal iron also promoted growth, with a maximum of ~60 g Chl-a L–1. These results indicated the bioavailability of colloidal iron.
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Han, Shuping, Wataru Naito, and Shigeki Masunaga. "Assessing bioavailability levels of metals in effluent-affected rivers: effect of Fe(III) and chelating agents on the distribution of metal speciation." Water Science and Technology 74, no. 4 (2016): 896–903. http://dx.doi.org/10.2166/wst.2016.269.
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To assess the effects of Fe(III) and anthropogenic ligands on the bioavailability of Ni, Cu, Zn, and Pb, concentrations of bioavailable metals were measured by the DGT (diffusive gradients in thin films) method in some urban rivers, and were compared with concentrations calculated by a chemical equilibrium model (WHAM 7.0). Assuming that dissolved Fe(III) (&lt;0.45 μm membrane filtered) was in equilibrium with colloidal iron oxide, the WHAM 7.0 model estimated that bioavailable concentrations of Ni, Cu, and Zn were slightly higher than the corresponding values estimated assuming that dissolved Fe(III) was absent. In contrast, lower levels of free Pb were predicted by the WHAM 7.0 model when dissolved Fe(III) was included. Estimates showed that most of the dissolved Pb was present as colloidal iron–Pb complex. Ethylene-diamine-tetra-acetic acid (EDTA) concentrations at sampling sites were predicted from the relationship between EDTA and the calculated bioavailable concentration of Zn. When both colloidal iron and predicted EDTA concentrations were included in the WHAM 7.0 calculations, dissolved metals showed a strong tendency to form EDTA complexes, in the order Ni &gt; Cu &gt; Zn &gt; Pb. With the inclusion of EDTA, bioavailable concentrations of Ni, Cu, and Zn predicted by WHAM 7.0 were different from those predicted considering only humic substances and colloidal iron.
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Roshan, Saeed, and Jingfeng Wu. "Dissolved and colloidal copper in the tropical South Pacific." Geochimica et Cosmochimica Acta 233 (July 2018): 81–94. http://dx.doi.org/10.1016/j.gca.2018.05.008.
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Weinberger, Robert, and L. J. Cline Love. "Triplet State Processes in Aqueous Colloidal Dispersions of Polycyclic Aromatic Hydrocarbons at Room Temperature." Applied Spectroscopy 39, no. 3 (1985): 516–19. http://dx.doi.org/10.1366/0003702854248629.
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A unique and facile means of producing room-temperature phosphorescence (RTP) from colloidal or microcrystalline suspensions of aromatic molecules in aqueous media is reported. Unlike previously reported RTP techniques, colloidal RTP is insensitive to quenching by dissolved oxygen. Delayed fluorescence was observed from several non-phosphorescent species. Potential uses of the technique are for the determination of the solubility of highly insoluble compounds and the ability to distinguish between suspended and dissolved matter.
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Gantenbein, Daniel, Joachim Schoelkopf, G. Peter Matthews, and Patrick A. C. Gane. "The development of hydrophobised ground calcium carbonate particles for the effective adsorption of dissolved and colloidal substances (DCS) from thermo mechanical pulp (TMP) filtrates." Nordic Pulp & Paper Research Journal 27, no. 1 (2012): 93–103. http://dx.doi.org/10.3183/npprj-2012-27-01-p093-103.
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Abstract Talc is often used to control unwanted deposition of resins and wood processing derivatives in the wet end circuit of a paper mill. It was the aim of this study to develop a calcium carbonate based mineral particle with improved pitch adsorption properties, and to compare these properties with those of talc. Partially treating the surface of the calcium carbonate with stearic acid led to improved adsorption of wood resin constituents and useful wetting properties. It was shown that the partially hydrophobised calcium carbonate had a higher capacity for the adsorption of the colloidal fraction of TMP than did the corresponding untreated calcium carbonate. Both calcium carbonates preferentially adsorb colloidal substances together with a minor amount of dissolved carbohydrates. In contrast, talc preferably adsorbs colloidal substances when the colloidal concentration is high but starts to adsorb substantial amounts of dissolved carbohydrates at lower concentration of colloidal wood resin droplets.
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Hart, Barry T., and Tina Hines. "Geochemistry of Cu, Zn and Fe in the Tambo River, Australia I. Oxidation of Fe(II)-rich water entering the river." Marine and Freshwater Research 59, no. 1 (2008): 72. http://dx.doi.org/10.1071/mf07056.
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The behaviour of Fe, Cu and Zn was studied during the laboratory oxidation of an acidic (pH 5.8) sample of naturally contaminated water from the Tambo River (Victoria, Australia). Changes in the concentrations of the dissolved, colloidal and particulate fractions of these metals were followed over 288 h. The initial concentrations of dissolved Cu (18.5 mg L–1) and Zn (22.6 mg L–1) were ~15-fold greater than that of the dissolved Fe (1.13 mg L–1). Dissolved Fe was completely removed from solution in 60 h, with removal following the well established first order oxidation kinetics for Fe(II). A relatively small amount of the dissolved Cu (18%) and dissolved Zn (14%) was removed from the solution, although the removal mechanisms appear to be different. A ‘co-precipitation-surface precipitation’ mechanism is proposed to explain the behaviour of the Cu and Zn, with Cu(II), Zn(II) and Fe(III) co-precipitating to form colloidal Fe(OH)3-Cu(OH)2-Zn(OH)2 particles following the initial oxidation of Fe(II) to Fe(III).
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Hoel, Hans, and Randi Aarsand. "Acute toxicity of colloidal and dissolved material in TMP effluents." Nordic Pulp & Paper Research Journal 10, no. 2 (1995): 98–103. http://dx.doi.org/10.3183/npprj-1995-10-02-p098-103.
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Mosbye, John, Marit Holtermann, Janne Laine, and Størker Moe. "Interaction between model colloidal wood resin, fillers and dissolved substances." Nordic Pulp & Paper Research Journal 18, no. 2 (2003): 194–99. http://dx.doi.org/10.3183/npprj-2003-18-02-p194-199.
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Jensen, Dorthe L., and Thomas H. Christensen. "Colloidal and dissolved metals in leachates from four Danish landfills." Water Research 33, no. 9 (1999): 2139–47. http://dx.doi.org/10.1016/s0043-1354(98)00414-x.
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Verplanck, Philip L. "Partitioning of Rare Earth Elements between Dissolved and Colloidal Phases." Procedia Earth and Planetary Science 7 (2013): 867–70. http://dx.doi.org/10.1016/j.proeps.2013.03.149.
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Kessler, John H., and James R. Hunt. "Dissolved and colloidal contaminant transport in a partially clogged fracture." Water Resources Research 30, no. 4 (1994): 1195–206. http://dx.doi.org/10.1029/93wr03555.
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Tang, Xiang-Yu, and Noam Weisbrod. "Dissolved and Colloidal Transport of Cesium in Natural Discrete Fractures." Journal of Environmental Quality 39, no. 3 (2010): 1066–76. http://dx.doi.org/10.2134/jeq2009.0345.
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Loiselle, L., U. Mohan Rao, I. Fofana, and T. Jaya. "Monitoring colloidal and dissolved decay particles in ester dielectric fluids." IEEE Transactions on Dielectrics and Electrical Insulation 27, no. 5 (2020): 1516–24. http://dx.doi.org/10.1109/tdei.2020.008719.
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Aiken, George, and Jerry Leenheer. "Isolation and Chemical Characterization of Dissolved and Colloidal Organic Matter." Chemistry and Ecology 8, no. 3 (1993): 135–51. http://dx.doi.org/10.1080/02757549308035305.
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Patel, P. D., and W. B. Russel. "An experimental study of aqueous colloidal suspensions containing dissolved polymer." Journal of Colloid and Interface Science 131, no. 1 (1989): 201–10. http://dx.doi.org/10.1016/0021-9797(89)90159-8.
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Moore, J. K., and O. Braucher. "Observations of dissolved iron concentrations in the World Ocean: implications and constraints for ocean biogeochemical models." Biogeosciences Discussions 4, no. 2 (2007): 1241–77. http://dx.doi.org/10.5194/bgd-4-1241-2007.
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Abstract. Analysis of a global compilation of dissolved iron observations provides insights into the controlling processes for iron distributions and some constraints for ocean biogeochemical models. The distribution of dissolved iron is consistent with the conceptual model developed for the scavenging of Th isotopes, whereby particle scavenging is a two-step process of scavenging mainly by colloidal and small particulates followed by aggregation and removal on larger sinking particles. Much of the dissolved iron (<0.4 μm) is present as small colloids (>~0.02 μm) and, thus, likely subject to aggregation and scavenging removal. Only the iron bound to soluble ligands (<~0.02 μm) is likely protected from scavenging removal. This implies distinct scavenging regimes for dissolved iron that appear consistent with the observational data: 1) high scavenging regime – where dissolved iron concentrations exceed the concentrations of strongly binding organic ligands; and 2) moderate scavenging regime – where dissolved iron is bound to both colloidal and soluble ligands. The removal rates for dissolved iron will be a function of biological uptake, number and size distributions of the colloidal and small particulate material, ligand dynamics, and the aggregation processes that lead to removal on larger particles. Inputs from dust deposition and continental sediments are key drivers of dissolved iron distributions. The observations provide several strong constraints for ocean biogeochemical models: 1) similar deep ocean concentrations in the North Atlantic and North Pacific (~0.6–0.8 nM), and much lower deep ocean dissolved iron concentrations in the Southern Ocean (~0.3–0.4 nM); 2) strong depletion of iron in the upper ocean away from the high dust deposition regions, with significant scavenging removal of dissolved iron below the euphotic zone; and 3) a bimodal distribution in surface waters with peaks less than 0.2 nM and between 0.6–0.8 nM. We compare the dissolved iron observations with output from the Biogeochemical Elemental Cycling (BEC) ocean model. The model output was in general agreement with the field data (r=0.76, for depths 103–502 m), but at lower iron concentrations (<0.3 nM) the model is consistently biased high relative to the observations.
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Senila, Marin, Erika Andrea Levei, Lacrimioara Ramona Senila, and Marius Roman. "Preliminary Investigation concerning Metals Bioavailability in Waters of Aries River Catchment by Using the Diffusive Gradients in Thin Films Technique." Journal of Chemistry 2015 (2015): 1–8. http://dx.doi.org/10.1155/2015/762121.
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The paper presents the metals content and bioavailability in waters of Aries River catchment, Romania. Concentration of labile dissolved metal species measured by diffusive gradients in thin films technique (DGT), metals in colloidal and in particulate phases, and also general physical-chemical indicators of water were determined. Very high total metal concentrations were found in the tributaries that drain the mining areas. However, the influence of the polluted tributaries on the Aries River water quality was moderate, as a consequence of the tributaries low flow rate compared with that of the Aries River. Using the DGT technique the bioavailable metals fractions expressed as % of total dissolved metals concentrations were found to be 28–88% for Cu, 43–72% for Zn, 73–85% for Fe, and 33–70% for Mn. Depending on the used method for dissolved metals determination the classification of waters according to quality classes may differ. Excluding the colloidal metal fractions, DGT measures only truly dissolved metal concentrations. In cases with very high metal contamination the differences between total dissolved and DGT-labile concentrations are unimportant for waters classification. However, where the metals concentration is near the thresholds values the determination method is very important.
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Conrad, Sarah, Johan Ingri, Johan Gelting, et al. "Distribution of Fe isotopes in particles and colloids in the salinity gradient along the Lena River plume, Laptev Sea." Biogeosciences 16, no. 6 (2019): 1305–19. http://dx.doi.org/10.5194/bg-16-1305-2019.
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Abstract. Riverine Fe input is the primary Fe source for the ocean. This study is focused on the distribution of Fe along the Lena River freshwater plume in the Laptev Sea using samples from a 600 km long transect in front of the Lena River mouth. Separation of the particulate (>0.22 µm), colloidal (0.22 µm–1 kDa), and truly dissolved (<1 kDa) fractions of Fe was carried out. The total Fe concentrations ranged from 0.2 to 57 µM with Fe dominantly as particulate Fe. The loss of >99 % of particulate Fe and about 90 % of the colloidal Fe was observed across the shelf, while the truly dissolved phase was almost constant across the Laptev Sea. Thus, the truly dissolved Fe could be an important source of bioavailable Fe for plankton in the central Arctic Ocean, together with the colloidal Fe. Fe-isotope analysis showed that the particulate phase and the sediment below the Lena River freshwater plume had negative δ56Fe values (relative to IRMM-14). The colloidal Fe phase showed negative δ56Fe values close to the river mouth (about −0.20 ‰) and positive δ56Fe values in the outermost stations (about +0.10 ‰). We suggest that the shelf zone acts as a sink for Fe particles and colloids with negative δ56Fe values, representing chemically reactive ferrihydrites. The positive δ56Fe values of the colloidal phase within the outer Lena River freshwater plume might represent Fe oxyhydroxides, which remain in the water column, and will be the predominant δ56Fe composition in the Arctic Ocean.
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Semenova, Maria G. "Proteins as functional components in colloidal foods." Current Opinion in Colloid & Interface Science 3, no. 6 (1998): 627–32. http://dx.doi.org/10.1016/s1359-0294(98)80091-5.
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Otterstedt, Jan-Erik A., Michel Ghuzel, and Johan P. Sterte. "Colloidal components in solutions of alkali silicates." Journal of Colloid and Interface Science 115, no. 1 (1987): 95–103. http://dx.doi.org/10.1016/0021-9797(87)90012-9.
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TIJERO, ANTONIO, M. CONCEPCION MONTE, and ANGELES BLANCO. "Use of talc to control problems associated with dissolved and colloidal material in papermaking." February 2012 11, no. 2 (2012): 43–51. http://dx.doi.org/10.32964/tj11.2.43.
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Increasingly stringent environmental standards and market demands are forcing pulp and paper mills to minimize both their water usage and their effluent discharge. Higher rates of process water reuse in pulp and paper mills leads to increased amounts of dissolved and colloidal substances in process water, which is a major fac¬tor limiting further closure of the water circuits. This study explores the use of different types of talc as control agents for dissolved and colloidal material contained in white water from paper mills using recovered and coated paper as raw materials. It also identifies the kinds of talc that can be used to control detrimental properties of the white water.
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Kamijo, Yasuyuki, Hiroshi Ono, and Takanori Miyanishi. "Adsorption of Anionic Dissolved and Colloidal Substances on the Calcium Carbonate." JAPAN TAPPI JOURNAL 52, no. 7 (1998): 959–67. http://dx.doi.org/10.2524/jtappij.52.959.
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Hokajo, Toshio. "The Measure for the Dissolved and Colloidal Substances in Linerboard Papermaking." JAPAN TAPPI JOURNAL 67, no. 10 (2013): 1118–22. http://dx.doi.org/10.2524/jtappij.67.1118.
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