Adsorption of Hg(II) by kaolinite was investigated as a function solution pH, ionic strength, and the competitive or complexation effects ligands (Cl, SO 4 , PO ) metals (Ni Pb). Mercury(II) adsorption from 0.6 μ M primarily influenced pH. The edge described pH 50 (pH where 50% occurs) 3.4 max maximum 4.4. At values above retention decreased with increasing Chloride Ni shifted to 7 4.1, respectively. Nickel Pb reduced amount adsorbed throughout range examined. Ionic strength presence had...

The influence of pH, ionic strength, ligands (Cl, SO 4 , PO ), and metals (Ni Pb) on the adsorption Hg(II) by quartz gibbsite was investigated to better understand process impact this process. triple layer model (TLM) used simulate both surfaces. Mercury(II) from a 0.6 μ M solution varies as function increasing an maximum with pH before tailing off constant level at high values. which occurs (pH max ≈ 4.5) is comparable p K (3.2) for hydrolysis Hg 2+ form Hg(OH) 0 2 Further, edge shifts much...

Abstract New urease and nitrification inhibitors polymer coatings were introduced in recent years, but their effects on N loss plant nutrition scarcely examined agronomic no-tillage production systems. A field experiment of urea treated with efficiency enhancers was conducted corn ( Zea mays L.) Tennessee, the USA during 2013–2015. ammonium nitrate (UAN) carried out Tennessee 2014 2015. Urea N-(n-butyl) thiophosphoric triamide (NBPT) at concentrations 20% (NBPT 1 ), 26.7% 2 or 30% 3 ) coated...

Woodchip bioreactor (WBR) is one of the green infrastructures in agriculture system to reduce nitrate from agricultural drainage and stormwater. A lot abiotic factors have been reported that affect removal lacking a comprehensive understanding. In this study, we studied eight important factors, including media age, hydraulic retention time (HRT), influent concentration (Cin), temperature, dissolved organic carbon (DOC), oxygen (DO), pH, effective porosity (ρe) WBR-filling materials. Based on...

Laser‐induced breakdown spectroscopy (LIBS) is an elemental analysis technique that based on the measurement of atomic emissions generated a sample surface by laser‐induced microplasma. Although often recognized in literature as well‐established analytical technique, LIBS remains untested relative to quantitative elements chemically complex matrices, such soils. The objective this study was evaluate capabilities characterization Approximately 65 soil samples from Pond Creek watershed east...

Agricultural antibiotics are commonly present in animal manures that applied to soil. The objective of this study was examine the influence pH, ionic strength, background electrolyte cation type, and dissolved organic C (DOC) concentration on adsorption chlortetracycline (CTC), tylosin (TYL), sulfamethazine (SMT) montmorillonite kaolinite. Surface complexation isotherm models were used analyze antibiotic adsorption. Adsorption CTC TYL decreased with increasing pH strength. also when Ca 2+...

Denitrifying bioreactors (DNBRs) are widely used to reduce excess nitrate from agricultural drainage. Their performance depends on the physical and chemical properties of substrate. Common substrate types have been partly reviewed in previous studies. However, few studies attempted determine a generalized pattern for role type removal. This study summarizes 41 substrates using dataset collected 63 peer-reviewed articles, which include 219 independent DNBR units. The classified into four...

Mammalian decomposition provides pulses of organic matter to the local ecosystem creating ephemeral hotspots nutrient cycling. While changes soil biogeochemistry in these have been described for C and N, patterns associated with deposition cycling other elements not received same attention. The goal our study was evaluate temporal a broad suite dissolved soils impacted by human on surface including: 1) abundant mineral body (K, Na, S, P, Ca, Mg), 2) trace (Fe, Mn, Se, Zn, Cu, Co, B), 3) Al...

Abstract Continuous no‐till production of cotton may result in vertical stratification nutrients similar to that observed for band fertilizer applications. If so, special soil sampling techniques be required adequately address the fertility status soils. The objective this study was evaluate nutrient relative planted row and with depth on three soils having broadcast K at various rates applied annually 6 years ( Gossypium hirsutum L.). Rows were within a few centimeters rows from previous...

Information on nitrogen (N) fertilization of no‐till (NT) cotton ( Gossypium hirsutum L.) is needed to optimize lint yields and earliness. We evaluated five N rates three application methods for NT production Loring silt loam (fine‐silty, mixed, active, thermic Oxyaquic Fragiudalfs) with natural winter annuals as a cover; Memphis Typic Hapludalfs) having corn Zea mays stover cover Lexington Utlic wheat Triticum aestivum cover. Nitrogen 0, 34, 67, 101, 134 kg ha −1 were either broadcasted...

ABSTRACT The use of large quantities neutral coal fly ash (NFA) may be facilitated by co‐application with a lime‐stabilized biosolid (LSB) for the reclamation acid mine spoil (AMS). Although NFA not aid in mitigation drainage, questions concerning leachability and mineralogy native NFA‐ LSB‐born metals must addressed. In this study, potential long‐term influence LSB on AMS leachate chemistry trace element was evaluated using laboratory weathering selective dissolution techniques. application...

Core Ideas Sb(V) adsorption by goethite decreases with increasing pH and is unaffected ionic strength. hysteretic. Adsorbed generates a downward shift in the isoelectric point. The of presence phosphate, but sulfate. Inner sphere mono‐ bidentate complexation predicted. Goethite sink for antimonate Sb(OH) 6 – [Sb(V)] soil sediments. pH‐ strength (I)‐dependent mass distribution between adsorbed solution phases at equilibrium may be used to indirectly infer an mechanism (inner vs. outer surface...

Abstract Sorption/desorption isotherms were used to evaluate the effects of solution composition on retention nickel (Ni) by soils varying physical and chemical properties. Soils examined included agricultural New Mexico, as well from potential waste disposal sites. Sorption Ni 0.01 N CaCl 2 was extensive for all samples: more than 99% added sorbed in some cases. Desorption slight (extreme hysteresis). Ability extract with diethlyenetriaminetetraacetate (DPTA), however, indicated that...

Core Ideas Soil management effects on depth distribution of SOC in southeastern US was studied. Significant response to long‐term tillage observed mostly the surface 5 cm. accumulation favored by corn and cotton systems than soybean down 22.5 Long‐term cover cropping did not increase total active SOC. There a strong significant positive relationship between POXC. organic carbon (SOC) content is strongly influenced agricultural practices. Leveraging three field experiments Tennessee, this...

Bone metastasis remains one of the biggest challenges in treatment prostate cancer, and other solid tumors such as breast, lung, colon. Modeling a complex microenvironment in-vitro bone niche, requires interrogation cell-cell interactions, specific extracellular matrix proteins, high calcium environment. Here, we present fast cost-effective system which commercially available, non-adhesive cell culture vessels are coated with amorphous phosphate (ACP) surrogate for matrix. We also modified...

ABSTRACT Background Veterinary antibiotic (VA) oxytetracycline (OTC) is commonly used in confined animal feeding operations to treat diseases, as a prophylactic and growth promoter. OTC can enter the environment via various routes, including runoff from stored manure stockpiles application of or contaminated irrigation water agricultural lands. Once introduced, could alter biogeochemical cycling coadsorbing ions, especially micronutrient oxyanions, such molybdate (MoO 4 2− ). Iron oxide...

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTCalcium molybdate solubility in spent oil shale and a preliminary evaluation of the association constants for formation CaMoO40(aq), KMoO4-(aq), NaMoO4-(aq)Michael E. EssingtonCite this: Environ. Sci. Technol. 1990, 24, 2, 214–220Publication Date (Print):February 1, 1990Publication History Published online1 May 2002Published inissue 1 February 1990https://pubs.acs.org/doi/10.1021/es00072a010https://doi.org/10.1021/es00072a010research-articleACS...

Antimony is a co‐contaminant with Pb in shooting range soils. The situ immobilization of these soils may be accomplished through the application PO 4 . However, impact this treatment on mobility and bioaccessibility Sb unknown. Further, ability to predict fate behavior contaminated soils, or as influenced by technologies, has not been suitably developed. objectives research were characterize adsorption Sb(V) birnessite (δ‐MnO 2 ) function ionic strength, pH, presence competing ligand (PO SO...

Abstract An empirical method developed for estimating the standard free energy of formation (Δ G° f ) solid phases is evaluated metal arsenates, selenates, and selenites. A function a phase found to be linearly correlated oxide Δ aqueous ion compound groups examined. The values estimated by this are, on average, within ± 10.9, 10.4, 12.0 kJ mol −1 experimental arsenate, selenate, selenite values, respectively. hydrated arsenates selenites also evaluated. selenites, are 23.7 10.0 ,...

Land application of manure can change soil chemical properties, thus affecting fate and mobility agricultural antibiotics in soil. The main objective this study was to examine the effects dissolved organic C (DOC) background electrolyte cation type on sorption transport chlortetracycline (CTC), tylosin (TYL), sulfamethazine (SMT) two different soils. A series batch isotherm column miscible displacement experiments were conducted using surface subsurface soils Etowah clay loam (fine‐loamy,...

Abstract Cell wall recalcitrance poses a major challenge on cellulosic biofuel production from feedstocks such as switchgrass ( Panicum virgatum L.). As lignin is known contributor of recalcitrance, transgenic plants with altered have been produced by downregulation caffeic acid O ‐methyltransferase COMT ). Field trials ‐downregulated previously demonstrated improved ethanol conversion no adverse agronomic effects. However, the rhizosphere impacts altering in are unknown. We hypothesized...