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You searched for: Journal name Environmental Science & Technology Remove constraint Journal name: Environmental Science & Technology Subject pH Remove constraint Subject: pH Subject equations Remove constraint Subject: equations Text Availability Citation in PubAg Remove constraint Text Availability: Citation in PubAg
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1. Arsenate–Ferrihydrite Systems from Minutes to Months: A Macroscopic and IR Spectroscopic Study of an Elusive Equilibrium

Author:
Swedlund Peter J.; Holtkamp Hannah; Song Yantao; Daughney Christopher J.
Source:
Environmental Science & Technology 2014 v.48 no.5 pp. 2759-2765
ISSN:
1520-5851
Subject:
arsenic; equations; ferrihydrite; models; pH; sorption; spectral analysis
Abstract:
... Sorption by ferrihydrite is an important control on As(V) concentrations in many oxic aquatic systems. There are significant discrepancies in reported sorption constants (log(KAₛ)), which presents a problem for quantifying and understanding this important system. A review of reported ferrihydrite–As(V) sorption studies indicated a positive correlation between reaction time used in the experiments ...
DOI:
10.1021/es404742c

2. The Biotic Ligand Model Can Successfully Predict the Uptake of a Trivalent Ion by a Unicellular Alga Below pH 6.50 but not Above: Possible Role of Hydroxo-Species

Author:
Crémazy Anne; Campbell Peter G. C.; Fortin Claude
Source:
Environmental Science & Technology 2013 v.47 no.5 pp. 2408-2415
ISSN:
1520-5851
Subject:
Chlamydomonas reinhardtii; algae; aluminum; bioavailability; dissociation; divalent metals; equations; ligands; models; pH; physiological transport; protons; radionuclides; scandium; trace elements
Abstract:
... In many reported cases, the biotic ligand model (BLM) has been shown to predict the bioavailability of divalent metals toward aquatic biota successfully. However, studies on the bioavailability of nonessential trivalent metals, including aluminum (Al), are relatively scarce. In the present study, short-term scandium (Sc) internalization fluxes (Jᵢₙₜ) were measured in Chlamydomonas reinhardtii in o ...
DOI:
10.1021/es3038388

3. Birnessite (δ-MnO2) Mediated Degradation of Organoarsenic Feed Additive p-Arsanilic Acid

Author:
Wang Lingling; Cheng Hefa
Source:
Environmental Science & Technology 2015 v.49 no.6 pp. 3473-3481
ISSN:
1520-5851
Subject:
adsorption; agricultural soils; animal wastes; animals; arsenates; arsenic; arsenites; birnessite; developing countries; equations; feed additives; feeds; free radicals; manganese dioxide; mineralization; pH; pollution; protons; risk
Abstract:
... p-Arsanilic acid (p-ASA), is a widely used animal feed additive in many developing countries, and is often introduced to agricultural soils with animal wastes. A common soil metal oxide, birnessite (δ-MnO₂), was found to mediate its degradation with fast rates under acidic conditions. Experimental results indicate that adsorption and degradation of p-ASA on the surface of δ-MnO₂ were highly pH dep ...
DOI:
10.1021/es505358c

4. The Dissolution Rates of SiO2 Nanoparticles As a Function of Particle Size

Author:
Diedrich Tamara; Dybowska Agnieszka; Schott Jacques; Valsami-Jones Eugenia; Oelkers Eric H.
Source:
Environmental Science & Technology 2012 v.46 no.9 pp. 4909-4915
ISSN:
1520-5851
Subject:
aqueous solutions; equations; nanoparticles; pH; particle size; prediction; silica; surface area; toxicity
Abstract:
... There is a critical need to better define the relationship among particle size, surface area, and dissolution rate for nanoscale materials to determine their role in the environment, their toxicity, and their technological utility. Although some previous studies concluded that nanoparticles dissolve faster than their bulk analogs, contradictory evidence suggests that nanoparticles dissolve more sl ...
DOI:
10.1021/es2045053

5. Effect of Sodium and Calcium Cations on the Ion-Exchange Affinity of Organic Cations for Soil Organic Matter

Author:
Droge Steven; Goss Kai-Uwe
Source:
Environmental Science & Technology 2012 v.46 no.11 pp. 5894-5901
ISSN:
1520-5851
Subject:
calcium chloride; peat; tertiary amines; bioavailability; calcium; equations; ion exchange; models; cations; soil; risk assessment; quaternary ammonium compounds; soil organic matter; sorption; pH; sodium; sodium chloride; ionic strength
Abstract:
... Sorption of organic cations to soil organic matter was studied using dynamic column experiments with different compositions of electrolytes in aqueous eluents. The sorption affinity of the tested variety of charged compounds, including primary, secondary, and tertiary amines and quaternary ammonium compounds, all showed the same response to different medium compositions. The sorption affinity to P ...
DOI:
10.1021/es204449r

6. Efficient Removal of Heavy Metal Ions with Biopolymer Template Synthesized Mesoporous Titania Beads of Hundreds of Micrometers Size

Author:
Wu Na; Wei Huanhuan; Zhang Lizhi
Source:
Environmental Science & Technology 2012 v.46 no.1 pp. 419-425
ISSN:
1520-5851
Subject:
cobalt; sodium hydroxide; copper; biopolymers; equations; heavy metals; alginates; models; surface area; cadmium; titanium dioxide; wastewater; porous media; adsorbents; pH; chromium; case studies; metal ions; adsorption
Abstract:
... We demonstrated that mesoporous titania beads of uniform size (about 450 μm) and high surface area could be synthesized via an alginate biopolymer template method. These mesoporous titania beads could efficiently remove Cr(VI), Cd(II), Cr(III), Cu(II), and Co(II) ions from simulated wastewater with a facile subsequent solid–liquid separation because of their large sizes. We chose Cr(VI) removal as ...
DOI:
10.1021/es202043u

7. Heteroaggregation of Titanium Dioxide Nanoparticles with Model Natural Colloids under Environmentally Relevant Conditions

Author:
Praetorius Antonia; Labille Jérôme; Scheringer Martin; Thill Antoine; Hungerbühler Konrad; Bottero Jean-Yves
Source:
Environmental Science & Technology 2014 v.48 no.18 pp. 10690-10698
ISSN:
1520-5851
Subject:
calcium chloride; colloids; environmental fate; equations; humic acids; ionic strength; methodology; models; nanoparticles; pH; risk assessment; silica; sodium chloride; surface water; titanium dioxide
Abstract:
... The heteroaggregation of engineered nanoparticles (ENPs) with natural colloids (NCs), which are ubiquitous in natural surface waters, is a crucial process affecting the environmental transport and fate of ENPs. Attachment efficiencies for heteroaggregation, αₕₑₜₑᵣₒ, are required as input parameters in environmental fate models to predict ENP concentrations and contribute to ENP risk assessment. He ...
DOI:
10.1021/es501655v

8. Kinetics and Pathways of Cyanide Degradation at High Temperatures and Pressures

Author:
Oulego Paula; Laca Adriana; Diaz Mario
Source:
Environmental Science & Technology 2013 v.47 no.3 pp. 1542-1549
ISSN:
1520-5851
Subject:
activation energy; alkaline hydrolysis; ammonia; carbon dioxide; cyanides; equations; formates; hydrogen; nitrogen; pH; pollutants; temperature; wastewater
Abstract:
... The degradation of cyanide was performed in a 1-L semibatch reactor at temperatures between 393 and 473 K and at total pressures in the range of 2.0–8.0 MPa. The initial pH of the solution was set at 11, whereas initial concentrations ranged from 3.85 to 25 mM, which resemble the typical concentrations of cyanide-containing wastewater. The change with time of cyanide concentration, intermediates, ...
DOI:
10.1021/es304000n

9. Oxidation Removal of Nitric Oxide from Flue Gas Using UV Photolysis of Aqueous Hypochlorite

Author:
Liu Yangxian; Wang Yan; Liu Ziyang; Wang Qian
Source:
Environmental Science & Technology 2017 v.51 no.20 pp. 11950-11959
ISSN:
1520-5851
Subject:
absorption; calcium; carbon dioxide; environmental science; equations; flue gas; hydroxyl radicals; light intensity; mathematical models; nitric oxide; oxidation; oxygen; pH; photolysis; sodium hypochlorite; spraying; sulfur dioxide; temperature
Abstract:
... The oxidation removal of nitric oxide (NO) from flue gas using UV photolysis of aqueous hypochlorite (Ca(ClO)₂ and NaClO) in a photochemical spraying reactor was studied. The key parameters (e.g., light intensity, hypochlorite concentration, solution temperature, solution pH, and concentration of NO, SO₂, O₂, and CO₂), mechanism and kinetics of NO oxidation removal were investigated. The results d ...
DOI:
10.1021/acs.est.7b03628

10. Parabola-Like Shaped pH-Rate Profile for Phenols Oxidation by Aqueous Permanganate

Author:
Du Juanshan; Sun Bo; Zhang Jing; Guan Xiaohong
Source:
Environmental Science & Technology 2012 v.46 no.16 pp. 8860-8867
ISSN:
1520-5851
Subject:
Gibbs free energy; chlorine; chlorophenols; equations; hydrogen bonding; models; oxidation; oxygen; pH; phenol; protons
Abstract:
... Oxidation of phenols by permanganate in the pH range of 5.0–9.0 generally exhibits a parabola-like shape with the maximum reaction rate obtained at pH close to phenols' pKₐ. However, a monotonic increase or decrease is observed if phenols' pKₐ is beyond the pH range of 5.0–9.0. A proton transfer mechanism is proposed in which the undissociated phenol is directly oxidized by permanganate to generat ...
DOI:
10.1021/es302076s

11. Partitioning of Organic Ions to Muscle Protein: Experimental Data, Modeling, and Implications for in Vivo Distribution of Organic Ions

Author:
Henneberger Luise; Goss Kai-Uwe; Endo Satoshi
Source:
Environmental Science & Technology 2016 v.50 no.13 pp. 7029-7036
ISSN:
1520-5851
Subject:
Gibbs free energy; anions; bioaccumulation; bovine serum albumin; cations; data collection; equations; humans; models; muscle protein; muscles; organic compounds; pH; partition coefficients; pharmacokinetics; salt concentration; sorption; sorption isotherms; structural proteins
Abstract:
... The in vivo partitioning behavior of ionogenic organic chemicals (IOCs) is of paramount importance for their toxicokinetics and bioaccumulation. Among other proteins, structural proteins including muscle proteins could be an important sorption phase for IOCs, because of their high quantity in the human and other animals’ body and their polar nature. Binding data for IOCs to structural proteins are ...
DOI:
10.1021/acs.est.6b01417

12. Phosphorus Removal by Steel Slag Filters: Modeling Dissolution and Precipitation Kinetics to Predict Longevity

Author:
Claveau-Mallet Dominique; Courcelles Benoît; Comeau Yves
Source:
Environmental Science & Technology 2014 v.48 no.13 pp. 7486-7493
ISSN:
1520-5851
Subject:
computer software; equations; filters; hydroxyapatite; longevity; mathematical models; monitoring; pH; phosphorus; prediction; slags; steel
Abstract:
... This article presents an original numerical model suitable for longevity prediction of alkaline steel slag filters used for phosphorus removal. The model includes kinetic rates for slag dissolution, hydroxyapatite and monetite precipitation and for the transformation of monetite into hydroxyapatite. The model includes equations for slag exhaustion. Short-term batch tests using slag and continuous ...
DOI:
10.1021/es500689t

13. Predicting the Sorption of Aromatic Acids to Noncarbonized and Carbonized Sorbents

Author:
Sigmund Gabriel; Sun Huichao; Hofmann Thilo; Kah Melanie
Source:
Environmental Science & Technology 2016 v.50 no.7 pp. 3641-3648
ISSN:
1520-5851
Subject:
2,4-D; 2,4-DB; MCPA (herbicide); activated carbon; anions; aromatic acids; carbon nanotubes; carbonization; equations; pH; pig manure; prediction; sewage sludge; sorbates; sorbents; sorption; sorption isotherms; surface area; wood shavings
Abstract:
... Approaches based on the octanol–water partition coefficient are commonly used to describe sorption of neutral organic compounds in environmental systems, but they are not suitable for organic acids, which can dissociate to form anions. We here investigate the applicability of an alternative approach based on the pH-dependent distribution ratio (DOW) to describe sorption of aromatic acids to sorben ...
DOI:
10.1021/acs.est.5b06033

14. Size-Controlled Dissolution of Organic-Coated Silver Nanoparticles

Author:
Ma Rui; Levard Clément; Marinakos Stella M.; Cheng Yingwen; Liu Jie; Michel F. Marc; Brown Gordon E.; Lowry Gregory V.
Source:
Environmental Science & Technology 2012 v.46 no.2 pp. 752-759
ISSN:
1520-5851
Subject:
X-radiation; absorption; coatings; crystal structure; equations; gum arabic; nanosilver; pH; particle size; polymers; silver; sodium bicarbonate; solubility; spectroscopy; surface tension; toxicity; transmission electron microscopy
Abstract:
... The solubility of Ag NPs can affect their toxicity and persistence in the environment. We measured the solubility of organic-coated silver nanoparticles (Ag NPs) having particle diameters ranging from 5 to 80 nm that were synthesized using various methods, and with different organic polymer coatings including poly(vinylpyrrolidone) and gum arabic. The size and morphology of Ag NPs were characteriz ...
DOI:
10.1021/es201686j

15. Steel Slag Filters to Upgrade Phosphorus Removal in Constructed Wetlands: Two Years of Field Experiments

Author:
Barca Cristian; Troesch Stéphane; Meyer Daniel; Drissen Peter; Andrès Yves; Chazarenc Florent
Source:
Environmental Science & Technology 2013 v.47 no.1 pp. 549-556
ISSN:
1520-5851
Subject:
arc furnaces; calcium phosphates; constructed wetlands; effluents; equations; field experimentation; filters; models; oxygen; pH; phosphorus; slags; steel; subsurface flow; temperature; wastewater
Abstract:
... Electric arc furnace steel slag (EAF-slag) and basic oxygen furnace steel slag (BOF-slag) were used as filter substrates in two horizontal subsurface flow filters (6 m³ each) designed to remove phosphorus (P) from the effluent of a constructed wetland. The influences of slag composition, void hydraulic retention time (HRTv), temperature, and wastewater quality on treatment performances were studie ...
DOI:
10.1021/es303778t

16. Stereoselective Degradation and Molecular Ecological Mechanism of Chiral Pesticides Beta-Cypermethrin in Soils with Different pH Values

Author:
Yang Zhong-Hua; Ji Guo-Dong
Source:
Environmental Science & Technology 2015 v.49 no.24 pp. 14166-14175
ISSN:
1520-5851
Subject:
cultivation area; enantiomers; equations; genes; microbial communities; pH; pesticides; soil; stereochemistry
Abstract:
... For decades, pesticides have been widely used for agricultural activities around the world, and the environmental problems caused by these compounds have raised widespread concern. However, the different enantioselective behaviors of chiral pesticide enantiomers are often ignored. Here, the selective degradation patterns and mechanisms of chiral pesticide enantiomers were successfully investigated ...
DOI:
10.1021/acs.est.5b04672

17. Use of Multiple Linear Regression Models for Setting Water Quality Criteria for Copper: A Complementary Approach to the Biotic Ligand Model

Author:
Brix Kevin V.; DeForest David K.; Tear Lucinda; Grosell Martin; Adams William J.
Source:
Environmental Science & Technology 2017 v.51 no.9 pp. 5182-5192
ISSN:
1520-5851
Subject:
United States Environmental Protection Agency; bioavailability; carbon; copper; covariance; environmental assessment; equations; freshwater; guidelines; hardness; hydrochemistry; ligands; linear models; pH; regression analysis; risk assessment; toxicity; water quality; water quality criteria; water quality standards; Europe
Abstract:
... Biotic Ligand Models (BLMs) for metals are widely applied in ecological risk assessments and in the development of regulatory water quality guidelines in Europe, and in 2007 the United States Environmental Protection Agency (USEPA) recommended BLM-based water quality criteria (WQC) for Cu in freshwater. However, to-date, few states have adopted BLM-based Cu criteria into their water quality standa ...
DOI:
10.1021/acs.est.6b05533

18. pH-Dependent Transport of Metal Cations in Porous Media

Author:
Prigiobbe Valentina; Bryant Steven L.
Source:
Environmental Science & Technology 2014 v.48 no.7 pp. 3752-3759
ISSN:
1520-5851
Subject:
acidity; adsorption; barium; calcium; carbon dioxide; carbon sequestration; cations; equations; hydrodynamic dispersion; hydrophilicity; industrial applications; ion exchange chromatography; iron oxides; laboratory experimentation; lithium; magnesium; models; pH; porous media; potassium; prediction; silica; sodium; solutes; strontium
Abstract:
... We study the effect of pH-dependent adsorption and hydrodynamic dispersion on cation transport through a reactive porous medium with a hydrophilic surface. We investigate how competitive adsorption between a proton and a metal (which in some situations of practical interest may also be a radionuclide) can facilitate the migration of a certain fraction of the latter. We performed laboratory experim ...
DOI:
10.1021/es403695r