Abstract: Recycling of advanced polymers and composites is a major problem facing the composites ... more Abstract: Recycling of advanced polymers and composites is a major problem facing the composites industry due not only to problems related to the actual process itself but also to liability issues associated with reuse. This paper presents the results of an investigation aimed at the reuse of waste pellets as aggregate in concrete to increase compression strength and ductility of the resulting concrete. A variety of glass filled materials including nylon, polycarbonate and polypropylene, as well as unreinforced polymers such as PET ...
Page 1. Remediation of Metal Contaminated Soil by EDTA Incorporating Electrochemical Recovery of ... more Page 1. Remediation of Metal Contaminated Soil by EDTA Incorporating Electrochemical Recovery of Metal and EDTA Herbert E. Allen* and Ping=Hsien Chen' Department of Civil Engineering, University of Delaware, Newark, DE 19716 ...
... An estimate of the amount of PAH that was not lost to volatilization during MeOH evaporation ... more ... An estimate of the amount of PAH that was not lost to volatilization during MeOH evaporation was achieved by allowing a soil-free blank to evaporate in the fume hood. ... Subsamples of these combined pools were used in all sub-sequent Fenton's oxidation experiments. ...
Bulletin of Environmental Contamination and Toxicology, 1983
Summary and conclusion The complexation capacities determined for natural waters by the Davey and... more Summary and conclusion The complexation capacities determined for natural waters by the Davey and the biological titration methods were statistically the same. However, these two methods differ in an important way. For Davey's method only those data in the vicinity of the equivalence point are used. For the biological titration all data can be used if the complex is strong.
Bulletin of Environmental Contamination and Toxicology, 1983
... Environm. Contam. Toxicol. 30, 37-43 (1983) Correlation of Copper Distribution in a Freshwate... more ... Environm. Contam. Toxicol. 30, 37-43 (1983) Correlation of Copper Distribution in a Freshwater-Sediment System to Bioavailability Diane M. Diks and Herbert E. Allen ... ratios of the sediments, adsorption isotherms were performed in 125 mL Wheaton vials to follow the distri-...
Environmental Restoration of Metals-Contaminated Soils, 2000
... for the middle graph is log Kom= 1.084+ 0.477 pH.(Top and bottom graphs are from Lee et al ..... more ... for the middle graph is log Kom= 1.084+ 0.477 pH.(Top and bottom graphs are from Lee et al ... 1.0 1.5 2.0 2.5 3.0 3.5 FIGURE 4.4 Sorption isotherm of Hg (II) on the Boonton Bergen loam. ... 5.96 6.49 6.98 PH FIGURE 4.5 Effect of Ca:* on Hg (ll) sorption onto the Booton Union loam ...
Assessing the Hazard of Metals and Inorganic Metal Substances in Aquatic and Terrestrial Systems, 2007
Disruption of library services 07/11-30/11 All library services will move to a new datacenter dur... more Disruption of library services 07/11-30/11 All library services will move to a new datacenter during the month of November. During this move many library services will be disturbed. Read more information on our library homepage. Sorry for any inconveniences.
... Crecelius EA, Jenne EA and Anthony JS (1987) Sediment quality criteria for metal: optimizatio... more ... Crecelius EA, Jenne EA and Anthony JS (1987) Sediment quality criteria for metal: optimization of extraction methods for determining the quantity of ... DiToro DM, Mahony JD, Hansen DJ, Scott KJ, Hicks MB, Mayr SM and Redmond MS (1990) Toxicity of cadmium in sediments ...
Effluents from publicly owned treatment works (POTWs) were mixed with Delaware River water at rat... more Effluents from publicly owned treatment works (POTWs) were mixed with Delaware River water at ratios of 1:1 or 1:2 effluent to Delaware River water. These mixing experiments were performed at pH 6, ambient pH and pH 8. In all mixing experiments, copper was released from effluent particulate matter when mixing was conducted at pH 6. No copper release was observed
We investigated Cu complexation by three dissolved organic matters (DOMs) collected by reverse os... more We investigated Cu complexation by three dissolved organic matters (DOMs) collected by reverse osmosis (RO). Alkalimetric titration, pH-stat Cu and Ca titrations, pH edges of Cu-DOM complexation, and Ca/Mg-Cu exchange experiments were investigated at 1 = 109-2)M for DOM samples of 10mg C/L. The proton and Cu binding characteristics indicated similarity for all three DOMs. All Cu titrations employed ion selective electrode measurement and indicated the presence of relatively small amounts of strong Cu-binding sites. Four distinct classes of Cu binding sites are required for FITEQL 4.0 to provide good fits to the entire curves. The estimated total Cu binding site density is 4.55 mmol/g C, much less than the total acidity but very close to the phenolic site content. Cu-DOM complexation increases approximately 10-fold per pH unit, even at relatively high pH (> 8). We suggest that sites characterized as phenolic based on alkalimetric titration, not carboxyl sites, account for the majority of Cu complexation under natural water conditions, and Cu-DOM complexation is principally through the replacement of H + by Cu2+ at the phenolic binding sites. The Cu-H exchange ratio is 1:1 for the first three sites and about 1:2 for the 4th site. This 4-site model describes well the pH dependency of Cu-DOM complexation and provides good estimates of free Cu concentrations throughout wide total copper (Cu(T)) and pH ranges. Comparison between Ca-DOM and Cu-DOM complexation demonstrated that (i) Ca-DOM complexation increases much less than an order of magnitude per pH unit and decreases at higher Ca concentration, different from that of Cu-DOM complexation; and (ii) Cu-DOM complexation is highly non-linear, in contrast to the much reduced extent of non-linearity of Ca-DOM complexation. Ca/Mg-Cu exchange experiments showed small competition effect, less than expected by a simple competition model, and the competition tended to reduce with increasing Ca or Mg concentrations. The extent of the competition by Mg and Ca are essentially comparable. Put all together, it suggests that Ca and Mg are preferably bound by carboxyl sites, especially at relatively high concentrations, resulting in a weakened apparent competition effect.
... of trace metals that cause the most significant biological effects is the free metal ion (Sun... more ... of trace metals that cause the most significant biological effects is the free metal ion (Sunda and Guillard, 1976; Sunda et al ... Ankley GT, SchubauerBerigan MK and Dierkes JR (199 !) Predicting the toxicity of bulk sediments to aquatic organisms with aqueous test fractions: pore ...
Dissolved organic matter (DOM) was concentrated from natural waters and the effluent of a wastewa... more Dissolved organic matter (DOM) was concentrated from natural waters and the effluent of a wastewater treatment plant using a portable reverse osmosis (RO) system. The humic acid (HA), fulvic acid (FA) and hydrophilic (HyI) fractions were isolated and purified by the XAD-8 resin combined with the cation exchange resin method. The FA fractions predominated in natural waters and accounted for 54-68% of the total amount of dissolved organic carbon (DOC), whereas the HA and HyI fractions constituted, respectively, 13-29 and 9-30% of the total DOC. The effluent of wastewater was almost devoid of HA and the HyI fraction exceeded FA. The elemental compositions of HA and FA were in the ranges typical for natural humic materials, but the HyI fractions did not exhibit humic character. 1H NMR spectra revealed that the HyI fractions were almost devoid of aromatic protons and the aliphatic region featured more sharp signals than HA and FA fractions, indicating that HyI fractions were consisted of more simple compounds and less complex mixtures. The aliphatic functional groups in these fractions of DOM samples followed the order HA < FA <HyI. Proton titrations indicated that HA. FA and HyI fractions of DOM samples from different sources had similar total acidity whose range was 9.0-11.6 meq/g C. This similarity may be due to the sample fractionation method. The copper titration results showed that the number of total Cu binding sites for the three fractions of different DOM samples were quite similar (1.46-1.60 mmol/g C), which was consistent with the similarity in total acidity from proton titrations. The affinity of copper with each isolated fraction followed the order HA approximately = FA > HyI. The rate of Cu complexation with the HyI fraction was faster than the rate with the HA or FA fraction of the Suwannee River DOM, implying that copper reacted with relatively weak ligands faster than with strong ligands.
... Table 1. Total recoverable copper (TRCu), alkalinity, dissolved organic carbon (DOC) and part... more ... Table 1. Total recoverable copper (TRCu), alkalinity, dissolved organic carbon (DOC) and particulate organic carbon (POC) for the three surface waters. Full-size table (1K). View Within Article. ... Davis (1982) reported an increased adsorption of DOC on an oxide surface at low pH. ...
Advertisement. Close Window. Close Window. Thank you for choosing to subscribe to the eTOC for So... more Advertisement. Close Window. Close Window. Thank you for choosing to subscribe to the eTOC for Soil Science. Enter your Email address: Wolters Kluwer Health may email you for journal alerts and information, but is committed ...
Suspended particles and river water from the Susquehanna River, White Clay Creek and the Delaware... more Suspended particles and river water from the Susquehanna River, White Clay Creek and the Delaware River were collected to experimentally study the partitioning of copper. The effects of many factors that may influence the partitioning coefficient (Kd) including pH, total suspended solids (TSS), total copper concentration ([Cu]T), dissolved organic matter (DOM), particulate organic matter (POM), hardness, and ionic strength were investigated by performing batch adsorption experiments. The results implied that organic matter binding sites in both the aqueous and solid phases play the most important role in controlling copper partitioning. Other major factors governing the partitioning are pH and TSS. Kd increases with pH in the pH range 3-8. TSS increases caused decreases in Kd values, which may be attributed to the decrease in the quantity of available binding sites caused by interparticle interactions, rather than by the redistribution of organic matter between solid and solution phases with the variation of TSS. Kd decreases slightly when total Cu concentration increases; however, Kd can be considered to be independent of Cu concentration when TSS is high. The effects of calcium competition and ionic strength on partitioning are small.
Abstract: Recycling of advanced polymers and composites is a major problem facing the composites ... more Abstract: Recycling of advanced polymers and composites is a major problem facing the composites industry due not only to problems related to the actual process itself but also to liability issues associated with reuse. This paper presents the results of an investigation aimed at the reuse of waste pellets as aggregate in concrete to increase compression strength and ductility of the resulting concrete. A variety of glass filled materials including nylon, polycarbonate and polypropylene, as well as unreinforced polymers such as PET ...
Page 1. Remediation of Metal Contaminated Soil by EDTA Incorporating Electrochemical Recovery of ... more Page 1. Remediation of Metal Contaminated Soil by EDTA Incorporating Electrochemical Recovery of Metal and EDTA Herbert E. Allen* and Ping=Hsien Chen' Department of Civil Engineering, University of Delaware, Newark, DE 19716 ...
... An estimate of the amount of PAH that was not lost to volatilization during MeOH evaporation ... more ... An estimate of the amount of PAH that was not lost to volatilization during MeOH evaporation was achieved by allowing a soil-free blank to evaporate in the fume hood. ... Subsamples of these combined pools were used in all sub-sequent Fenton's oxidation experiments. ...
Bulletin of Environmental Contamination and Toxicology, 1983
Summary and conclusion The complexation capacities determined for natural waters by the Davey and... more Summary and conclusion The complexation capacities determined for natural waters by the Davey and the biological titration methods were statistically the same. However, these two methods differ in an important way. For Davey's method only those data in the vicinity of the equivalence point are used. For the biological titration all data can be used if the complex is strong.
Bulletin of Environmental Contamination and Toxicology, 1983
... Environm. Contam. Toxicol. 30, 37-43 (1983) Correlation of Copper Distribution in a Freshwate... more ... Environm. Contam. Toxicol. 30, 37-43 (1983) Correlation of Copper Distribution in a Freshwater-Sediment System to Bioavailability Diane M. Diks and Herbert E. Allen ... ratios of the sediments, adsorption isotherms were performed in 125 mL Wheaton vials to follow the distri-...
Environmental Restoration of Metals-Contaminated Soils, 2000
... for the middle graph is log Kom= 1.084+ 0.477 pH.(Top and bottom graphs are from Lee et al ..... more ... for the middle graph is log Kom= 1.084+ 0.477 pH.(Top and bottom graphs are from Lee et al ... 1.0 1.5 2.0 2.5 3.0 3.5 FIGURE 4.4 Sorption isotherm of Hg (II) on the Boonton Bergen loam. ... 5.96 6.49 6.98 PH FIGURE 4.5 Effect of Ca:* on Hg (ll) sorption onto the Booton Union loam ...
Assessing the Hazard of Metals and Inorganic Metal Substances in Aquatic and Terrestrial Systems, 2007
Disruption of library services 07/11-30/11 All library services will move to a new datacenter dur... more Disruption of library services 07/11-30/11 All library services will move to a new datacenter during the month of November. During this move many library services will be disturbed. Read more information on our library homepage. Sorry for any inconveniences.
... Crecelius EA, Jenne EA and Anthony JS (1987) Sediment quality criteria for metal: optimizatio... more ... Crecelius EA, Jenne EA and Anthony JS (1987) Sediment quality criteria for metal: optimization of extraction methods for determining the quantity of ... DiToro DM, Mahony JD, Hansen DJ, Scott KJ, Hicks MB, Mayr SM and Redmond MS (1990) Toxicity of cadmium in sediments ...
Effluents from publicly owned treatment works (POTWs) were mixed with Delaware River water at rat... more Effluents from publicly owned treatment works (POTWs) were mixed with Delaware River water at ratios of 1:1 or 1:2 effluent to Delaware River water. These mixing experiments were performed at pH 6, ambient pH and pH 8. In all mixing experiments, copper was released from effluent particulate matter when mixing was conducted at pH 6. No copper release was observed
We investigated Cu complexation by three dissolved organic matters (DOMs) collected by reverse os... more We investigated Cu complexation by three dissolved organic matters (DOMs) collected by reverse osmosis (RO). Alkalimetric titration, pH-stat Cu and Ca titrations, pH edges of Cu-DOM complexation, and Ca/Mg-Cu exchange experiments were investigated at 1 = 109-2)M for DOM samples of 10mg C/L. The proton and Cu binding characteristics indicated similarity for all three DOMs. All Cu titrations employed ion selective electrode measurement and indicated the presence of relatively small amounts of strong Cu-binding sites. Four distinct classes of Cu binding sites are required for FITEQL 4.0 to provide good fits to the entire curves. The estimated total Cu binding site density is 4.55 mmol/g C, much less than the total acidity but very close to the phenolic site content. Cu-DOM complexation increases approximately 10-fold per pH unit, even at relatively high pH (> 8). We suggest that sites characterized as phenolic based on alkalimetric titration, not carboxyl sites, account for the majority of Cu complexation under natural water conditions, and Cu-DOM complexation is principally through the replacement of H + by Cu2+ at the phenolic binding sites. The Cu-H exchange ratio is 1:1 for the first three sites and about 1:2 for the 4th site. This 4-site model describes well the pH dependency of Cu-DOM complexation and provides good estimates of free Cu concentrations throughout wide total copper (Cu(T)) and pH ranges. Comparison between Ca-DOM and Cu-DOM complexation demonstrated that (i) Ca-DOM complexation increases much less than an order of magnitude per pH unit and decreases at higher Ca concentration, different from that of Cu-DOM complexation; and (ii) Cu-DOM complexation is highly non-linear, in contrast to the much reduced extent of non-linearity of Ca-DOM complexation. Ca/Mg-Cu exchange experiments showed small competition effect, less than expected by a simple competition model, and the competition tended to reduce with increasing Ca or Mg concentrations. The extent of the competition by Mg and Ca are essentially comparable. Put all together, it suggests that Ca and Mg are preferably bound by carboxyl sites, especially at relatively high concentrations, resulting in a weakened apparent competition effect.
... of trace metals that cause the most significant biological effects is the free metal ion (Sun... more ... of trace metals that cause the most significant biological effects is the free metal ion (Sunda and Guillard, 1976; Sunda et al ... Ankley GT, SchubauerBerigan MK and Dierkes JR (199 !) Predicting the toxicity of bulk sediments to aquatic organisms with aqueous test fractions: pore ...
Dissolved organic matter (DOM) was concentrated from natural waters and the effluent of a wastewa... more Dissolved organic matter (DOM) was concentrated from natural waters and the effluent of a wastewater treatment plant using a portable reverse osmosis (RO) system. The humic acid (HA), fulvic acid (FA) and hydrophilic (HyI) fractions were isolated and purified by the XAD-8 resin combined with the cation exchange resin method. The FA fractions predominated in natural waters and accounted for 54-68% of the total amount of dissolved organic carbon (DOC), whereas the HA and HyI fractions constituted, respectively, 13-29 and 9-30% of the total DOC. The effluent of wastewater was almost devoid of HA and the HyI fraction exceeded FA. The elemental compositions of HA and FA were in the ranges typical for natural humic materials, but the HyI fractions did not exhibit humic character. 1H NMR spectra revealed that the HyI fractions were almost devoid of aromatic protons and the aliphatic region featured more sharp signals than HA and FA fractions, indicating that HyI fractions were consisted of more simple compounds and less complex mixtures. The aliphatic functional groups in these fractions of DOM samples followed the order HA < FA <HyI. Proton titrations indicated that HA. FA and HyI fractions of DOM samples from different sources had similar total acidity whose range was 9.0-11.6 meq/g C. This similarity may be due to the sample fractionation method. The copper titration results showed that the number of total Cu binding sites for the three fractions of different DOM samples were quite similar (1.46-1.60 mmol/g C), which was consistent with the similarity in total acidity from proton titrations. The affinity of copper with each isolated fraction followed the order HA approximately = FA > HyI. The rate of Cu complexation with the HyI fraction was faster than the rate with the HA or FA fraction of the Suwannee River DOM, implying that copper reacted with relatively weak ligands faster than with strong ligands.
... Table 1. Total recoverable copper (TRCu), alkalinity, dissolved organic carbon (DOC) and part... more ... Table 1. Total recoverable copper (TRCu), alkalinity, dissolved organic carbon (DOC) and particulate organic carbon (POC) for the three surface waters. Full-size table (1K). View Within Article. ... Davis (1982) reported an increased adsorption of DOC on an oxide surface at low pH. ...
Advertisement. Close Window. Close Window. Thank you for choosing to subscribe to the eTOC for So... more Advertisement. Close Window. Close Window. Thank you for choosing to subscribe to the eTOC for Soil Science. Enter your Email address: Wolters Kluwer Health may email you for journal alerts and information, but is committed ...
Suspended particles and river water from the Susquehanna River, White Clay Creek and the Delaware... more Suspended particles and river water from the Susquehanna River, White Clay Creek and the Delaware River were collected to experimentally study the partitioning of copper. The effects of many factors that may influence the partitioning coefficient (Kd) including pH, total suspended solids (TSS), total copper concentration ([Cu]T), dissolved organic matter (DOM), particulate organic matter (POM), hardness, and ionic strength were investigated by performing batch adsorption experiments. The results implied that organic matter binding sites in both the aqueous and solid phases play the most important role in controlling copper partitioning. Other major factors governing the partitioning are pH and TSS. Kd increases with pH in the pH range 3-8. TSS increases caused decreases in Kd values, which may be attributed to the decrease in the quantity of available binding sites caused by interparticle interactions, rather than by the redistribution of organic matter between solid and solution phases with the variation of TSS. Kd decreases slightly when total Cu concentration increases; however, Kd can be considered to be independent of Cu concentration when TSS is high. The effects of calcium competition and ionic strength on partitioning are small.
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