scholarly journals Seasonality and sunlight dependency of manganese oxide formation and cycling in surface waters of a meromictic pond

2021 ◽  
Author(s):  
Hayley Gadol ◽  
Chadlin Ostrander ◽  
Lina Taenzer ◽  
Veronique Oldham ◽  
Luciana Villarroel ◽  
...  
Keyword(s):  
Manganese Oxide ◽  
Surface Waters ◽  
Oxide Formation

scholarly journals Thermodynamic Constrains on Smectite and Iron Oxide Formation at Gale Crater, Mars: Insights into Potential Free Energy from Aerobic Fe Oxidation in Lake Water–Groundwater Mixing Zone

Minerals ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 341
Author(s):  
Sakiko Kikuchi ◽  
Takazo Shibuya
Keyword(s):  
Iron Oxides ◽  
Surface Waters ◽  
Fluid Mixing ◽  
Habitable Zone ◽  
Mixing Zone ◽  
Oxide Formation ◽  
Lacustrine Environment ◽  
Gale Crater ◽  
Metabolic Reactions ◽  
Temperature Water

The presence of saponite and iron oxides in Sheepbed mudstone of Yellowknife Bay at Gale crater on Mars is considered as evidence of a habitable fluvio-lacustrine environment for chemolithoautotrophy. However, the energetic availability for metabolic reactions is poorly constrained. Herein, we propose the possible mixing of surface water and groundwater that (i) explains the formation of magnetite and hematite detected in Sheepbed mudstone and (ii) may work as a potential habitable zone for aerobic Fe2+-oxidizing microbes. Our thermodynamic modeling of water–rock reactions revealed that the formation of abundant saponite in Sheepbed mudstone may occur under various conditions of water-to-rock mass ratios, temperatures (5–200 °C), and initial fluid compositions. In contrast, the formation of iron oxides in the mudstone can be explained only by the mixing of Fe2+-rich groundwater and more oxidized surface waters, where the Fe2+-rich groundwater can be generated by the low-temperature water–rock reactions with a CO2-bearing initial fluid. The calculated bioavailable energy of aerobic Fe2+ oxidation in the fluid-mixing zone on Mars is similar to that estimated for a fluid-mixing zone on Earth actually inhabited by aerobic Fe2+-oxidizing microbes. The findings will contribute to a better understanding of potential habitability on Mars.

Fungal oxidative dissolution of the Mn(II)-bearing mineral rhodochrosite and the role of metabolites in manganese oxide formation

2012 ◽  
Vol 15 (4) ◽  
pp. 1063-1077 ◽  
Author(s):  
Yuanzhi Tang ◽  
Carolyn A. Zeiner ◽  
Cara M. Santelli ◽  
Colleen M. Hansel
Keyword(s):  
Manganese Oxide ◽  
Oxidative Dissolution ◽  
Oxide Formation

scholarly journals Inhibited manganese oxide formation hinders cobalt scavenging in the Ross Sea

2021 ◽  
Author(s):  
Véronique E. Oldham ◽  
Rebecca Chmiel ◽  
Colleen M. Hansel ◽  
Giacomo R. DiTullio ◽  
Deepa Rao ◽  
...  
Keyword(s):  
Manganese Oxide ◽  
Ross Sea ◽  
Oxide Formation

scholarly journals Manganese Oxide Formation in Lanthanum Strontium Manganite-Yttria-Stabilized Zirconia SOFC Cathodes

2014 ◽  
Vol 1 (3) ◽  
pp. 263-271
Author(s):  
Hsiang-Jen Wang ◽  
Mark R. De Guire ◽  
Zhengliang Xing ◽  
Gerry Agnew ◽  
Richard Goettler ◽  
...  
Keyword(s):  
Manganese Oxide ◽  
Yttria Stabilized Zirconia ◽  
Lanthanum Strontium Manganite ◽  
Oxide Formation ◽  
Stabilized Zirconia ◽  
Lanthanum Strontium

Concurrent sorption of As(V) and Mn(II) during biogenic manganese oxide formation

2012 ◽  
Vol 306-307 ◽  
pp. 123-128 ◽  
Author(s):  
Jun'ichi Watanabe ◽  
Yukinori Tani ◽  
Naoyuki Miyata ◽  
Haruhiko Seyama ◽  
Satoshi Mitsunobu ◽  
...  
Keyword(s):  
Manganese Oxide ◽  
Oxide Formation

Microbial manganese oxide formation and interaction with toxic metal ions

2007 ◽  
Vol 104 (1) ◽  
pp. 1-8 ◽  
Author(s):  
Naoyuki Miyata ◽  
Yukinori Tani ◽  
Masahiro Sakata ◽  
Keisuke Iwahori
Keyword(s):  
Metal Ions ◽  
Manganese Oxide ◽  
Toxic Metal ◽  
Oxide Formation ◽  
Toxic Metal Ions

Habitat Association of Klebsiella Species

1985 ◽  
Vol 6 (2) ◽  
pp. 52-58 ◽  
Author(s):  
Susan T. Bagley
Keyword(s):  
Drinking Water ◽  
Gastrointestinal Tract ◽  
Surface Waters ◽  
Industrial Effluents ◽  
Opportunistic Pathogen ◽  
Habitat Associations ◽  
Habitat Association ◽  
Klebsiella Species ◽  
Almost All ◽  
Polluted Waters

AbstractThe genus Klebsiella is seemingly ubiquitous in terms of its habitat associations. Klebsiella is a common opportunistic pathogen for humans and other animals, as well as being resident or transient flora (particularly in the gastrointestinal tract). Other habitats include sewage, drinking water, soils, surface waters, industrial effluents, and vegetation. Until recently, almost all these Klebsiella have been identified as one species, ie, K. pneumoniae. However, phenotypic and genotypic studies have shown that “K. pneumoniae” actually consists of at least four species, all with distinct characteristics and habitats. General habitat associations of Klebsiella species are as follows: K. pneumoniae—humans, animals, sewage, and polluted waters and soils; K. oxytoca—frequent association with most habitats; K. terrigena— unpolluted surface waters and soils, drinking water, and vegetation; K. planticola—sewage, polluted surface waters, soils, and vegetation; and K. ozaenae/K. rhinoscleromatis—infrequently detected (primarily with humans).

Identifying Sources of Sulfate Aerosols Reaching Whiteface Mountain, NY

1985 ◽  
Vol 43 ◽  
pp. 98-101
Author(s):  
James S. Webber
Keyword(s):  
Trace Metals ◽  
Acid Deposition ◽  
Surface Waters ◽  
Dry Deposition ◽  
Coal Combustion ◽  
Public Awareness ◽  
Sulfate Aerosols ◽  
Wet And Dry Deposition ◽  
Whiteface Mountain ◽  
Toxic Trace Metals

INTRODUCTION“Acid rain” and “acid deposition” are terms no longer confined to the lexicon of atmospheric scientists and 1imnologists. Public awareness of and concern over this phenomenon, particularly as it affects acid-sensitive regions of North America, have increased dramatically in the last five years. Temperate ecosystems are suffering from decreased pH caused by acid deposition. Human health may be directly affected by respirable sulfates and by the increased solubility of toxic trace metals in acidified waters. Even man's monuments are deteriorating as airborne acids etch metal and stone features.Sulfates account for about two thirds of airborne acids with wet and dry deposition contributing equally to acids reaching surface waters or ground. The industrial Midwest is widely assumed to be the source of most sulfates reaching the acid-sensitive Northeast since S02 emitted as a byproduct of coal combustion in the Midwest dwarfs S02 emitted from all sources in the Northeast.

STEM and ELS Observation of Early Oxide Formation on the Surface of Cr Thin Films

1980 ◽  
Vol 38 ◽  
pp. 412-413
Author(s):  
Fumio Watari ◽  
J. M. Cowley
Keyword(s):  
Thin Films ◽  
Optical System ◽  
Room Temperature ◽  
Oxide Formation ◽  
Initial Nucleation ◽  
Diffraction Patterns ◽  
Relationship Of ◽  
Multiple Twinning ◽  
Moderately High Temperature

STEM coupled with the optical system was used for the investigation of the early oxidation on the surface of Cr. Cr thin films (30 – 1000Å) were prepared by evaporation onto the polished or air-cleaved NaCl substrates at room temperature and 45°C in a vacuum of 10−6 Torr with an evaporation speed 0.3Å/sec. Rather thick specimens (200 – 1000Å) with various preferred orientations were used for the investigation of the oxidation at moderately high temperature (600 − 1100°C). Selected area diffraction patterns in these specimens are usually very much complicated by the existence of the different kinds of oxides and their multiple twinning. The determination of the epitaxial orientation relationship of the oxides formed on the Cr surface was made possible by intensive use of the optical system and microdiffraction techniques. Prior to the formation of the known rhombohedral Cr2O3, a thin spinel oxide, probably analogous to γ -Al203 or γ -Fe203, was formed. Fig. 1a shows the distinct epitaxial growth of the spinel (001) as well as the rhombohedral (125) on the well-oriented Cr(001) surface. In the case of the Cr specimen with the (001) preferred orientation (Fig. 1b), the rings explainable by spinel structure appeared as well as the well defined epitaxial spots of the spinel (001). The microdif fraction from 20A areas (Fig. 2a) clearly shows the same pattern as Fig. Ia with the weaker oxide spots among the more intense Cr spots, indicating that the thickness of the oxide is much less than that of Cr. The rhombohedral Cr2O3 was nucleated preferably at the Cr(011) sites provided by the polycrystalline nature of the present specimens with the relation Cr2O3 (001)//Cr(011), and by further oxidation it grew into full coverage of the rest of the Cr surface with the orientation determined by the initial nucleation.

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