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You searched for: Journal name Environmental Science & Technology Remove constraint Journal name: Environmental Science & Technology Subject term pH Remove constraint Subject term: pH
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1. 1H NMR Metabolomics Reveals Contrasting Response by Male and Female Mussels Exposed to Reduced Seawater pH, Increased Temperature, and a Pathogen

Author:
Ellis Robert P.; Spicer John I.; Byrne Jonathan J.; Sommer Ulf; Viant Mark R.; White Daniel A.; Widdicombe Steve
Source:
Environmental Science & Technology 2014 v.48 no.12 pp. 7044-7052
ISSN:
1520-5851
Subject:
Mytilus edulis; animal pathogenic bacteria; aquatic invertebrates; disease outbreaks; ecosystems; energy metabolism; females; humans; males; metabolome; metabolomics; mussels; nuclear magnetic resonance spectroscopy; ocean acidification; oceans; pH; seawater; stress response; temperature
Abstract:
... Human activities are fundamentally altering the chemistry of the world’s oceans. Ocean acidification (OA) is occurring against a background of warming and an increasing occurrence of disease outbreaks, posing a significant threat to marine organisms, communities, and ecosystems. In the current study, ¹H NMR spectroscopy was used to investigate the response of the blue mussel, Mytilus edulis, to a ...
DOI:
10.1021/es501601w

2. 54Mn Radiotracers Demonstrate Continuous Dissolution and Reprecipitation of Vernadite (δ-MnO2) during Interaction with Aqueous Mn(II)

Author:
Elzinga Evert J.
Source:
Environmental Science & Technology 2016 v.50 no.16 pp. 8670-8677
ISSN:
1520-5851
Subject:
X-ray absorption spectroscopy; X-ray diffraction; electron transfer; manganese; mineralogy; pH
Abstract:
... ⁵⁴Mn radiotracers were used to assess Mn atom exchange between aqueous Mn(II) and vernadite (δ-MnO₂) at pH 5.0. Continuous solid–liquid redistribution of ⁵⁴Mn atoms occurred, and systems are near isotopic equilibrium after reaction for 3 months. Despite this extensive exchange, X-ray diffraction and X-ray absorption spectroscopy data showed no major changes in vernadite bulk mineralogy. These resu ...
DOI:
10.1021/acs.est.6b02874

3. A General Model for Kinetics of Heavy Metal Adsorption and Desorption on Soils

Author:
Shi Zhenqing; Di Toro Dominic M.; Allen Herbert E.; Sparks Donald L.
Source:
Environmental Science & Technology 2013 v.47 no.8 pp. 3761-3767
ISSN:
1520-5851
Subject:
reaction kinetics; copper; zinc; calcium; heavy metals; lead; models; soil organic matter; soil; carbon; adsorbents; pH; binding capacity; desorption; adsorption
Abstract:
... In this study, we propose a general kinetics model for heavy metal adsorption and desorption reactions in soils when soil organic matter (SOM) is the dominant adsorbent. The kinetics model, integrated with the equilibrium speciation model WHAM VI, specifically considers metal reactions with SOM and dissolved organic matter (DOM) and accounts for the variations of solution chemistry. Metal reaction ...
DOI:
10.1021/es304524p

4. A Mn-54 Radiotracer Study of Mn Isotope Solid–Liquid Exchange during Reductive Transformation of Vernadite (δ-MnO2) by Aqueous Mn(II)

Author:
Elzinga Evert J.; Kustka Adam B.
Source:
Environmental Science & Technology 2015 v.49 no.7 pp. 4310-4316
ISSN:
1520-5851
Subject:
anaerobic conditions; cations; electron transfer; isotopes; manganese; manganese oxides; oxygen; pH; reducing agents; superoxide anion; tracer techniques
Abstract:
... We employed Mn-54 radiotracers to characterize the extent and dynamics of Mn atom exchange between aqueous Mn(II) and vernadite (δ-Mn(IV)O₂) at pH 7.5 under anoxic conditions. Exchange of Mn atoms between the solid and liquid phase is rapid, reaching dynamic equilibrium in 2–4 days. We propose that during the initial stages of reaction, Mn atom exchange occurs through consecutive comproportionatio ...
DOI:
10.1021/acs.est.5b00022

5. A Modified Polanyi-based Model for Mechanistic Understanding of Adsorption of Phenolic Compounds onto Polymeric Adsorbents

Author:
Pan Bingjun; Zhang Huichun
Source:
Environmental Science & Technology 2012 v.46 no.12 pp. 6806-6814
ISSN:
1520-5851
Subject:
acidity; adsorbents; adsorption; energy; hexadecane; hydrogen bonding; hydrophobic bonding; models; pH; phenols; polystyrenes; solubility; solutes; sorption isotherms
Abstract:
... To obtain mechanistic insight into adsorption of phenolic compounds by two representative polymeric adsorbents, XAD-4 (polystyrene) and XAD-7 (polymethacrylate), a modified Polanyi-based Dubinin-Ashtakhov (D–A) model was developed based on a unique combination of the Polanyi theory, polyparameter linear energy relationships and infinitely dilute solution in n-hexadecane as the reference state. The ...
DOI:
10.1021/es300951g

6. A Multimedia Fate Model to Support Chemical Management in China: A Case Study for Selected Trace Organics

Author:
Zhu Ying; Price Oliver R.; Kilgallon John; Rendal Cecilie; Tao Shu; Jones Kevin C.; Sweetman Andrew J.
Source:
Environmental Science & Technology 2016 v.50 no.13 pp. 7001-7009
ISSN:
1520-5851
Subject:
UV filters; anti-infective agents; case studies; chemical risk assessment; environmental assessment; freshwater; industry; ionization; irrigated farming; model validation; models; monitoring; pH; prediction; quantitative risk assessment; sediments; soil; China
Abstract:
... SESAMe v3.3, a spatially explicit multimedia fate model for China, is a tool suggested to support quantitative risk assessment for national scale chemical management. The key advantage over the previous version SESAMe v3.0 is consideration of spatially varied environmental pH. We evaluate the model performance using estimates of emission from total industry usage of three UV filters (benzophenone- ...
DOI:
10.1021/acs.est.5b05769

7. A New Group of Disinfection Byproducts in Drinking Water: Trihalo-hydroxy-cyclopentene-diones

Author:
Pan Yang; Li Wenbin; Li Aimin; Zhou Qing; Shi Peng; Wang Ying
Source:
Environmental Science & Technology 2016 v.50 no.14 pp. 7344-7352
ISSN:
1520-5851
Subject:
Fourier transform infrared spectroscopy; absorption; bromine; byproducts; chlorination; detection limit; disinfection; freeze drying; mass spectrometry; monitoring; pH; tap water; ultra-performance liquid chromatography; wavelengths
Abstract:
... We report the detection, synthesis, preparative isolation, structure characterization and identification, and formation of a new group of drinking water disinfection byproducts (DBPs): trihalo-hydroxy-cyclopentene-diones (trihalo-HCDs). With ultra performance liquid chromatography (UPLC)/electrospray ionization-triple quadruple mass spectrometry analyses (full scans, multiple reaction monitoring, ...
DOI:
10.1021/acs.est.6b00798

8. A New Mechanism in Electrochemical Process for Arsenic Oxidation: Production of H2O2 from Anodic O2 Reduction on the Cathode under Automatically Developed Alkaline Conditions

Author:
Qian Ao; Yuan Songhu; Zhang Peng; Tong Man
Source:
Environmental Science & Technology 2015 v.49 no.9 pp. 5689-5696
ISSN:
1520-5851
Subject:
arsenic; bicarbonates; calcium; cathodes; electrochemistry; groundwater; humic acids; hydrogen peroxide; magnesium; oxidation; oxygen; pH; sand; soil pore water; solutes; superoxide anion
Abstract:
... Electrochemical cathodes are often used to reduce contaminants or produce oxidizing substances (i.e., H₂O₂). Alkaline conditions develop automatically around the cathode in electrochemical processes, and O₂ diffuses onto the cathode easily. However, limited attention is paid to contaminant transformation by the reactive species produced on the cathode under oxic and alkaline conditions due to the ...
DOI:
10.1021/acs.est.5b00808

9. A Novel Anaerobic Electrochemical Membrane Bioreactor (AnEMBR) with Conductive Hollow-fiber Membrane for Treatment of Low-Organic Strength Solutions

Author:
Katuri Krishna P.; Werner Craig M.; Jimenez-Sandoval Rodrigo J.; Chen Wei; Jeon Sungil; Logan Bruce E.; Lai Zhiping; Amy Gary L.; Saikaly Pascal E.
Source:
Environmental Science & Technology 2014 v.48 no.21 pp. 12833-12841
ISSN:
1520-5851
Subject:
acetates; biogas; cathodes; chemical oxygen demand; electric power; electrochemistry; electrolysis; energy; fouling; hydrogen; hydrogen production; membrane bioreactors; methane; microfiltration; pH; wastewater treatment
Abstract:
... A new anaerobic treatment system that combined a microbial electrolysis cell (MEC) with membrane filtration using electrically conductive, porous, nickel-based hollow-fiber membranes (Ni-HFMs) was developed to treat low organic strength solution and recover energy in the form of biogas. This new system is called an anaerobic electrochemical membrane bioreactor (AnEMBR). The Ni-HFM served the dual ...
DOI:
10.1021/es504392n

10. A Universal Method for Flocculating Harmful Algal Blooms in Marine and Fresh Waters Using Modified Sand

Author:
Li Liang; Pan Gang
Source:
Environmental Science & Technology 2013 v.47 no.9 pp. 4555-4562
ISSN:
1520-5851
Subject:
Amphidinium; Chlorella; Microcystis aeruginosa; Moringa oleifera; algae; algal blooms; biodegradability; chitosan; flocculants; freshwater; isoelectric point; pH; sand; seawater
Abstract:
... A universal environmental friendly method was developed to turn sand into effective flocculants for mitigating harmful algal blooms (HABs) in marine and freshwater systems. The isoelectric point of sand was largely increased from pH 4.5 to 10.5 after been modified by Moringa oleifera coagulant (MO) abstracted form MO seeds. However, when sand was modified by MO alone, maximum removal efficiencies ...
DOI:
10.1021/es305234d

11. ABTS as an Electron Shuttle to Enhance the Oxidation Kinetics of Substituted Phenols by Aqueous Permanganate

Author:
Song Yang; Jiang Jin; Ma Jun; Pang Su-Yan; Liu Yong-ze; Yang Yi; Luo Cong-wei; Zhang Jian-qiao; Gu Jia; Qin Wen
Source:
Environmental Science & Technology 2015 v.49 no.19 pp. 11764-11771
ISSN:
1520-5851
Subject:
aqueous solutions; cations; manganese; oxidation; pH; phenol; potassium permanganate
Abstract:
... In this study, it was, interestingly, found that 2,2′-azino-bis(3-ethylbenzothiazoline)-6-sulfonate (ABTS), a widely used electron shuttle, could greatly accelerate the oxidation of substituted phenols by potassium permanganate (Mn(VII)) in aqueous solutions at pH 5–9. This was attributed to the fact that these substituted phenols could be readily oxidized by the stable radical cation (ABTS•⁺), wh ...
DOI:
10.1021/acs.est.5b03358

12. ATR-FTIR Spectroscopy Study of the Influence of pH and Contact Time on the Adhesion of Shewanella putrefaciens Bacterial Cells to the Surface of Hematite

Author:
Elzinga Evert J.; Huang Jen-How; Chorover Jon; Kretzschmar Ruben
Source:
Environmental Science & Technology 2012 v.46 no.23 pp. 12848-12855
ISSN:
1520-5851
Subject:
Fourier transform infrared spectroscopy; Shewanella putrefaciens; bacterial adhesion; biofilm; cell walls; hematite; pH; phosphates; sorption
Abstract:
... Attachment of live cells of Shewanella putrefaciens strain CN-32 to the surface of hematite (α-Fe₂O₃) was studied with in situ ATR-FTIR spectroscopy at variable pH (4.5–7.7) and contact times up to 24 h. The IR spectra indicate that phosphate based functional groups on the cell wall play an important role in mediating adhesion through formation of inner-sphere coordinative bonds to hematite surfac ...
DOI:
10.1021/es303318y

13. Abiotic Hydrolysis of Fluorotelomer-Based Polymers as a Source of Perfluorocarboxylates at the Global Scale

Author:
Washington John W.; Jenkins Thomas M.
Source:
Environmental Science & Technology 2015 v.49 no.24 pp. 14129-14135
ISSN:
1520-5851
Subject:
half life; hydrolysis; industry; pH; perfluorooctanoic acid; polymers
Abstract:
... Fluorotelomer-based polymers (FTPs) are the main product of the fluorotelomer industry. For nearly 10 years, whether FTPs degrade to form perfluorooctanoate (PFOA) and perfluorocarboxylate (PFCA) homologues has been vigorously contested. Here we show that circum-neutral abiotic hydrolysis of a commercial FTP proceeds with half-life estimates of 55–89 years and that base-mediated hydrolysis overtak ...
DOI:
10.1021/acs.est.5b03686

14. Abiotic Reduction Reactions of Dichloroacetamide Safeners: Transformations of “Inert” Agrochemical Constituents

Author:
Sivey John D.; Roberts A. Lynn
Source:
Environmental Science & Technology 2012 v.46 no.4 pp. 2187-2195
ISSN:
1520-5851
Subject:
Gibbs free energy; active ingredients; adsorption; agrochemicals; chlorine; chromium; goethite; hematite; herbicides; hydrogen; pH; reducing agents; toxicity
Abstract:
... Safeners are so-called “inert” constituents of herbicide formulations added to protect crops from the toxic effects of herbicides. We examined the reactivity of three dichloroacetamide safeners and 12 structural analogues [all neutral compounds of the form Cl₂CXC(=O)NRR′; X = H, Cl; R-groups include alkyl, branched alkyl, n-allyl, and cyclic moieties] in one homogeneous and two heterogeneous reduc ...
DOI:
10.1021/es203755h

15. Accelerated Catalytic Fenton Reaction with Traces of Iron: An Fe–Pd-Multicatalysis Approach

Author:
Georgi Anett; Velasco Polo Miriam; Crincoli Klara; Mackenzie Katrin; Kopinke Frank-Dieter
Source:
Environmental Science & Technology 2016 v.50 no.11 pp. 5882-5891
ISSN:
1520-5851
Subject:
catalysts; deuterium; half life; hydrogen peroxide; hydroxyl radicals; iron; isotopes; models; oxidants; oxidation; pH; reducing agents; sludge
Abstract:
... An accelerated catalytic Fenton (ACF) reaction was developed based upon a multicatalysis approach, facilitating efficient contaminant oxidation at trace levels of dissolved iron. Beside the Feᴵᴵ/H₂O₂ catalyst/oxidant pair for production of OH-radicals, the ACF system contains Pd/H₂ as catalyst/reductant pair for fast reduction of Feᴵᴵᴵ back to Feᴵᴵ which accelerates the Fenton cycle and leads to f ...
DOI:
10.1021/acs.est.6b01049

16. Acetonitrile and N-Chloroacetamide Formation from the Reaction of Acetaldehyde and Monochloramine

Author:
Kimura Susana Y.; Vu Trang Nha; Komaki Yukako; Plewa Michael J.; Mariñas Benito J.
Source:
Environmental Science & Technology 2015 v.49 no.16 pp. 9954-9963
ISSN:
1520-5851
Subject:
acetaldehyde; acetonitrile; activation energy; amides; byproducts; chlorine; cytotoxicity; disinfection; drinking water; enthalpy; ethane; genotoxicity; lethal concentration 50; models; ozone; pH; water distribution
Abstract:
... Nitriles and amides are two classes of nitrogenous disinfection byproducts (DBPs) associated with chloramination that are more cytotoxic and genotoxic than regulated DBPs. Monochloramine reacts with acetaldehyde, a common ozone and free chlorine disinfection byproduct, to form 1-(chloroamino)ethanol. Equilibrium (K₁) and forward and reverse rate (k₁,k–₁) constants for the reaction between initial ...
DOI:
10.1021/acs.est.5b01875

17. Acid Rock Drainage Treatment Using Membrane Distillation: Impacts of Chemical-Free Pretreatment on Scale Formation, Pore Wetting, and Product Water Quality

Author:
Hull Eric J.; Zodrow Katherine R.
Source:
Environmental Science & Technology 2017 v.51 no.20 pp. 11928-11934
ISSN:
1520-5851
Subject:
distillation; drainage; electrolytes; geothermal energy; heat; heavy metals; hydrophobicity; iron oxyhydroxides; methodology; minerals; models; oxidation; pH; rivers; sulfates; temperature; vapors; wastewater; water quality; United States
Abstract:
... Acid rock drainage (ARD) is a metal-rich wastewater that forms upon oxidation of sulfidic minerals. Although ARD impacts >12,000 miles of rivers in the U.S. and has an estimated cleanup cost of $32–$72 billion, the low pH and high metal concentrations in ARD make rapid, high volume treatment without chemical addition difficult. This research focuses on a novel method of ARD treatment, membrane dis ...
DOI:
10.1021/acs.est.7b02957

18. Acid Rock Drainage and Rock Weathering in Antarctica: Important Sources for Iron Cycling in the Southern Ocean

Author:
Dold B.; Gonzalez-Toril E.; Aguilera A.; Lopez-Pamo E.; Cisternas M. E.; Bucchi F.; Amils R.
Source:
Environmental Science & Technology 2013 v.47 no.12 pp. 6129-6136
ISSN:
1520-5851
Subject:
Acidithiobacillus; Thiobacillus; acid mine drainage; coasts; drainage; global warming; groundwater; iron; microorganisms; mineralization; pH; phytoplankton; runoff; sulfides; weathering; Antarctic region; Antarctica
Abstract:
... Here we describe biogeochemical processes that lead to the generation of acid rock drainage (ARD) and rock weathering on the Antarctic landmass and describe why they are important sources of iron into the Antarctic Ocean. During three expeditions, 2009–2011, we examined three sites on the South Shetland Islands in Antarctica. Two of them displayed intensive sulfide mineralization and generated aci ...
DOI:
10.1021/es305141b

19. Acid-Catalyzed Transformation of Ionophore Veterinary Antibiotics: Reaction Mechanism and Product Implications

Author:
Sun Peizhe; Yao Hong; Minakata Daisuke; Crittenden John C.; Pavlostathis Spyros G.; Huang Ching-Hua
Source:
Environmental Science & Technology 2013 v.47 no.13 pp. 6781-6789
ISSN:
1520-5851
Subject:
active sites; agricultural runoff; anti-infective properties; environmental factors; environmental fate; kinetics; land application; livestock and meat industry; monensin; narasin; pH; poultry manure; salinomycin; soil; toxicity; veterinary drugs
Abstract:
... Ionophore antibiotics (IPAs) are polyether antimicrobials widely used in the livestock industry and may enter the environment via land application of animal waste and agricultural runoff. Information is scarce regarding potential transformation of IPAs under environmental conditions. This study is among the first to identify the propensity of IPAs to undergo acid-catalyzed transformation in mildly ...
DOI:
10.1021/es3044517

20. Activation of Manganese Oxidants with Bisulfite for Enhanced Oxidation of Organic Contaminants: The Involvement of Mn(III)

Author:
Sun Bo; Guan Xiaohong; Fang Jingyun; Tratnyek Paul G.
Source:
Environmental Science & Technology 2015 v.49 no.20 pp. 12414-12421
ISSN:
1520-5851
Subject:
absorbance; ciprofloxacin; free radicals; manganese; manganese dioxide; oxidants; oxidation; pH; phenol; spectroscopy; sulfates; tap water; water treatment
Abstract:
... MnO₄– was activated by HSO₃–, resulting in a process that oxidizes organic contaminants at extraordinarily high rates. The permanganate/bisulfite (PM/BS) process oxidized phenol, ciprofloxacin, and methyl blue at pHᵢₙᵢ 5.0 with rates (kₒbₛ ≈ 60–150 s–¹) that were 5–6 orders of magnitude faster than those measured for permanganate alone, and ∼5 to 7 orders of magnitude faster than conventional adva ...
DOI:
10.1021/acs.est.5b03111