Effect of Fe (oxyhydr)oxide morphology on phytic acid transport under saturated flow condition

<p>Natural iron (oxyhydr)oxides are ubiquitous in subsurface environments. Phytic acid (myo-inositol hexaphosphate, IHP), a dominant form of organic phosphate (OP) in organic carbon-rich surface soils, strongly binds with Fe (oxyhydr)oxide. The cotransport of IHP and Fe (oxyhydr)oxide with different morphology under acid and alkaline conditions in the subsurface is mostly overlooked. These cotransport processes are critical for P (bio)geochemical processes in the subsurface that is rich in Fe (oxyhydr)oxides. Three Fe (oxyhydr)oxides (ferrihydrite, hematite, and goethite) were chosen in this study, and the cotransport of IHP and Fe (oxyhydr)oxide was investigated in saturated columns by injecting Fe (oxyhydr)oxide under different IHP concentrations (0, 10, 25, 50, and 100 &#181;M) at pH of 5 and 10. The presence of IHP significantly enhanced the mobility of Fe (oxyhydr)oxide at both pH 5 and 10 due to the stronger electrostatic repulsion between Fe (oxyhydr)oxide and quartz sand. At low IHP concentrations (< 50 &#181;M IHP), goethite with a rod-like morphology showed strong mobility due to its orientation transport along with the water flow streamline. The mobility of amorphous Fe (oxyhydr)oxide, ferrihydrite, was much slower than the goethite. However, ferrihydrite could facilitate more IHP transport due to its sorption capacity for IHP that is higher than goethite and hematite. At high IHP concentrations (> 50 &#956;M), surface precipitation might have occurred on ferrihydrite because of its poorly ordered crystallinity, which contributed to its less negatively charged surface and weak ferrihydrite facilitated IHP transport. The new insight provided in this study is important for evaluating the transport behavior and impact of IHP in a saturated solum rich in Fe (oxyhydr)oxides.</p>

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Dissolution kinetics of meta-torbernite under circum-neutral to alkaline conditions

Environmental Chemistry ◽

10.1071/en09046 ◽

2009 ◽

Vol 6 (6) ◽

pp. 551 ◽

Cited By ~ 4

Author(s):

Dawn M. Wellman ◽

Bruce K. McNamara ◽

Diana H. Bacon ◽

Elsa A. Cordova ◽

Ruby M. Ermi ◽

...

Keyword(s):

Dissolution Kinetics ◽

Coupled Processes ◽

Effect Of Temperature ◽

Subsurface Environments ◽

Alkaline Conditions ◽

Flow Through ◽

Uranium Phosphate ◽

The Stability ◽

Kinetics Of

Environmental context. Uranium-phosphate minerals have been identified as a long-term controlling phase that limit the mobility of uranium to groundwater in many contaminated subsurface environments. Complex, coupled processes confound the ability to isolate the rates attributed to individual processes. Results of this investigation provide the necessary information to refine current prediction on the release and long-term fate of uranium in subsurface environments. Abstract. The purpose of this investigation was to conduct a series of single-pass flow-through (SPFT) tests to (1) quantify the effect of temperature (23–90°C) and pH (6–10) on meta-torbernite dissolution; (2) compare the dissolution of meta-torbernite to other autunite-group minerals; and (3) evaluate the effect of aqueous phosphate on the dissolution kinetics of meta-torbernite. Results presented here illustrate meta-torbernite dissolution rates increase by ~100× over the pH interval of 6 to 10, irrespective of temperature. The power law coefficient for meta-torbernite, η = 0.59 ± 0.07, is greater than that quantified for Ca-meta-autunite, η = 0.42 ± 0.12. This suggests the stability of meta-torbernite is greater than that of meta-autunite, which is reflected in the predicted stability constants. The rate equation for the dissolution of meta-torbernite as a function of aqueous phosphate concentration is log rdissol (mol m–2 s–1) = –4.7 × 10–13 + 4.1 × 10–10[PO43–].

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Phytic acid transport in Phaseolus vulgaris: A new low phytic acid mutant in the PvMRP1 gene and study of the PvMRPs promoters in two different plant systems

Plant Science ◽

10.1016/j.plantsci.2018.02.003 ◽

2018 ◽

Vol 270 ◽

pp. 1-12 ◽

Cited By ~ 17

Author(s):

Eleonora Cominelli ◽

Massimo Confalonieri ◽

Martina Carlessi ◽

Gaia Cortinovis ◽

Maria Gloria Daminati ◽

...

Keyword(s):

Phaseolus Vulgaris ◽

Phytic Acid ◽

Acid Transport ◽

Low Phytic Acid

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LDPE and HDPE Microplastics Differently Affect the Transport of Tetracycline in Saturated Porous Media

Materials ◽

10.3390/ma14071757 ◽

2021 ◽

Vol 14 (7) ◽

pp. 1757

Author(s):

Enzhu Hu ◽

Hongbo Yuan ◽

Yichun Du ◽

Xijuan Chen

Keyword(s):

High Density Polyethylene ◽

Solution Chemistry ◽

Low Density Polyethylene ◽

Low Density ◽

Saturated Porous Media ◽

Zeta Potentials ◽

Surface Areas ◽

Subsurface Environments ◽

Alkaline Conditions ◽

Neutral Conditions

The accumulation of microplastics (MPs) in soil and sediments may influence the penetration of contaminants into subsurface environments. However, little attention has been paid to comparing the different roles of two common polyethylene (PE) types—low-density polyethylene (LDPE) and high-density polyethylene (HDPE). In this study, the transport behaviors of tetracycline in saturated quartz sand columns in the presence and absence of these two MPs were investigated, respectively. The results showed that both types of PE MPs restrained the mobility of tetracycline at neutral conditions, while such detrimental effects were weak at acid and alkaline conditions. The degree of nonequilibrium adsorption was higher, and tetracycline transferred easier to the kinetic site for the existence of LDPE than of HDPE. The increased roughness and Brunauer-Emmett-Teller (BET) surface areas, more negative zeta potentials and the formation of oxygen function groups on the surface of MPs after UV-weathering intensified the retardation of tetracycline transport. This study revealed that the PE type and weathering should be taken into account in risk assessment, along with the solution chemistry.

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Neuroprotective effect of the natural iron chelator, phytic acid in a cell culture model of Parkinson's disease

Toxicology ◽

10.1016/j.tox.2007.12.017 ◽

2008 ◽

Vol 245 (1-2) ◽

pp. 101-108 ◽

Cited By ~ 69

Author(s):

Qi Xu ◽

Anumantha G. Kanthasamy ◽

Manju B. Reddy

Keyword(s):

Parkinson’S Disease ◽

Cell Culture ◽

Parkinson's Disease ◽

Phytic Acid ◽

Neuroprotective Effect ◽

Iron Chelator ◽

Cell Culture Model ◽

Culture Model ◽

Natural Iron ◽

A Cell

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A crystalline–amorphous Ni–Ni(OH)2 core–shell catalyst for the alkaline hydrogen evolution reaction

Journal of Materials Chemistry A ◽

10.1039/d0ta08735a ◽

2020 ◽

Vol 8 (44) ◽

pp. 23323-23329

Author(s):

Jing Hu ◽

Siwei Li ◽

Yuzhi Li ◽

Jing Wang ◽

Yunchen Du ◽

...

Keyword(s):

Hydrogen Evolution ◽

Hydrogen Evolution Reaction ◽

Electrocatalytic Activity ◽

Core Shell ◽

Alkaline Conditions

Crystalline–amorphous Ni–Ni(OH)2 core–shell assembled nanosheets exhibit outstanding electrocatalytic activity and stability for hydrogen evolution under alkaline conditions.

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