Microbial Dissolution of Hematite and Associated Cellular Fossilization by Reduced Iron Phases: A Study of Ancient Microbe-Mineral Surface Interactions

Astrobiology ◽  
2009 ◽  
Vol 9 (8) ◽  
pp. 777-796 ◽  
Author(s):  
Kamal Kolo ◽  
Kurt Konhauser ◽  
Wolfgang Elisabeth Krumbein ◽  
Yves Van Ingelgem ◽  
Annick Hubin ◽  
...  
Keyword(s):  
Surface Interactions ◽  
Mineral Surface

Probing Surface Interactions of Electrochemically Active Galena Mineral Surface Using Atomic Force Microscopy

2016 ◽  
Vol 120 (39) ◽  
pp. 22433-22442 ◽  
Author(s):  
Lei Xie ◽  
Jingyi Wang ◽  
Chen Shi ◽  
Jun Huang ◽  
Hao Zhang ◽  
...  
Keyword(s):  
Atomic Force Microscopy ◽  
Surface Interactions ◽  
Mineral Surface ◽  
Force Microscopy ◽  
Atomic Force ◽  
Electrochemically Active

Bubble–surface interactions with graphite in the presence of adsorbed carboxymethylcellulose

Soft Matter ◽  
2015 ◽  
Vol 11 (3) ◽  
pp. 587-599 ◽  
Author(s):  
Jueying Wu ◽  
Iliana Delcheva ◽  
Yung Ngothai ◽  
Marta Krasowska ◽  
David A. Beattie
Keyword(s):  
Contact Angle ◽  
Polymer Concentration ◽  
Adsorbed Layer ◽  
Surface Interactions ◽  
Bubble Surface ◽  
Graphite Surface ◽  
Mineral Surface ◽  
Film Rupture ◽  
Bubble Rise ◽  
Wetting Film

Bubble rise and collision against a graphite surface pre-treated with an adsorbed layer of carboxymethylcellulose. The adsorbed layer can prolong wetting film rupture, dramatically slow the dewetting of the mineral surface, and reduce the final contact angle of the bubble. Adsorption of CMC from a solution of higher polymer concentration amplifies the effect of the polymer.

Studies of mineral surface interactions with water using pycnometric measurements

2010 ◽  
Vol 69 (3) ◽  
pp. 411-419 ◽  
Author(s):  
C. Butenuth ◽  
M. H. de Freitas ◽  
N. Passas ◽  
V. Butenova
Keyword(s):  
Surface Interactions ◽  
Mineral Surface

Organic solute-mineral surface interactions: A new method for the determination of groundwater velocities

1980 ◽  
Vol 16 (1) ◽  
pp. 217-223 ◽  
Author(s):  
Paolo Ciccioli ◽  
William T. Cooper ◽  
Paul M. Hammer ◽  
J. M. Hayes
Keyword(s):  
Surface Interactions ◽  
New Method ◽  
Mineral Surface ◽  
Organic Solute

Scanning Electron Microscope Study of Bacteria on Mineral Surfaces

1976 ◽  
Vol 34 ◽  
pp. 130-131
Author(s):  
V.K. Berry
Keyword(s):  
Oxidation Reaction ◽  
Electron Microscope Study ◽  
Elemental Sulfur ◽  
Thiobacillus Ferrooxidans ◽  
Physical Contact ◽  
Metal Sulfides ◽  
Low Grade ◽  
Mineral Surfaces ◽  
Mineral Surface ◽  
Scanning Electron Microscope Study

There are two strains of bacteria viz. Thiobacillus thiooxidansand Thiobacillus ferrooxidanswidely mentioned to play an important role in the leaching process of low-grade ores. Another strain used in this study is a thermophile and is designated Caldariella .These microorganisms are acidophilic chemosynthetic aerobic autotrophs and are capable of oxidizing many metal sulfides and elemental sulfur to sulfates and Fe2+ to Fe3+. The necessity of physical contact or attachment by bacteria to mineral surfaces during oxidation reaction has not been fairly established so far. Temple and Koehler reported that during oxidation of marcasite T. thiooxidanswere found concentrated on mineral surface. Schaeffer, et al. demonstrated that physical contact or attachment is essential for oxidation of sulfur.

Study of Tip-Surface Interactions in Scanning Tunneling Microscopy (STM) by Reflection Electron Microscopy (REM)

1990 ◽  
Vol 48 (1) ◽  
pp. 320-321
Author(s):  
W. Lo ◽  
J.C.H. Spence ◽  
M. Kuwabara
Keyword(s):  
High Resolution ◽  
Elastic Strain ◽  
Tunneling Current ◽  
Surface Damage ◽  
Surface Interactions ◽  
Graphite Surface ◽  
Scanning Tunneling ◽  
Large Area ◽  
Tunneling Microscopy ◽  
High Resolution Tem

Work on the integration of STM with REM has demonstrated the usefulness of this combination. The STM has been designed to replace the side entry holder of a commercial Philips 400T TEM. It allows simultaneous REM imaging of the tip/sample region of the STM (see fig. 1). The REM technique offers nigh sensitivity to strain (<10−4) through diffraction contrast and high resolution (<lnm) along the unforeshortened direction. It is an ideal technique to use for studying tip/surface interactions in STM.The elastic strain associated with tunnelling was first imaged on cleaved, highly doped (S doped, 5 × 1018cm-3) InP(110). The tip and surface damage observed provided strong evidence that the strain was caused by tip/surface contact, most likely through an insulating adsorbate layer. This is consistent with the picture that tunnelling in air, liquid or ordinary vacuum (such as in a TEM) occurs through a layer of contamination. The tip, under servo control, must compress the insulating contamination layer in order to get close enough to the sample to tunnel. The contaminant thereby transmits the stress to the sample. Elastic strain while tunnelling from graphite has been detected by others, but never directly imaged before. Recent results using the STM/REM combination has yielded the first direct evidence of strain while tunnelling from graphite. Figure 2 shows a graphite surface elastically strained by the STM tip while tunnelling (It=3nA, Vtip=−20mV). Video images of other graphite surfaces show a reversible strain feature following the tip as it is scanned. The elastic strain field is sometimes seen to extend hundreds of nanometers from the tip. Also commonly observed while tunnelling from graphite is an increase in the RHEED intensity of the scanned region (see fig.3). Debris is seen on the tip and along the left edges of the brightened scan region of figure 4, suggesting that tip abrasion of the surface has occurred. High resolution TEM images of other tips show what appear to be attached graphite flakes. The removal of contamination, possibly along with the top few layers of graphite, seems a likely explanation for the observed increase in RHEED reflectivity. These results are not inconsistent with the “sliding planes” model of tunnelling on graphite“. Here, it was proposed that the force due to the tunnelling probe acts over a large area, causing shear of the graphite planes when the tip is scanned. The tunneling current is then modulated as the planes of graphite slide in and out of registry. The possiblity of true vacuum tunnelling from the cleaned graphite surface has not been ruled out. STM work function measurements are needed to test this.

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