In this study, effects of solid concentration, temperature, and initial Fe2+ concentration on bioleaching of sulfide mineral (chalcopyrite) obtained from Sarcheshmeh Copper Mine in the region of Kerman located in the south of Iran were investigated. A mesophilic iron oxidizing bacterium, Acidithiobacillus ferrooxidans has been isolated from a typical chalcopyrite copper concentra...

Spinodal decomposition is an important mechanism of exsolution. However, spinodal has not been observed in natural sulfide intergrowths. We utilized focused ion beam (FIB) and transmission electron microscopy (TEM) techniques to confirm intergrowths (chalcopyrite bornite). According FIB TEM analyses, occurred as small curving alternating dark bright fluctuations bornite–chalcopyrite Due the low...

Introduction: Most martian meteorites are highly shocked, with plagioclase transformed to maskelynite or even melted and partially crystallized [1,2]. These responses to shock conditions on Mars provide clues to the nature of the ejection events for martian meteorites and to local shock conditions. Where new-to-science phases are discovered, meteoritic occurrences can also inform the study of e...

A reductive tricarboxylic acid (rTCA) cycle could have fixed carbon dioxide as biochemically useful energy-storage molecules on early Earth. Nonenzymatic chemical pathways for some steps of the rTCA cycle, however, such as the production of the alpha-ketocarboxylic acids pyruvate and alpha-ketoglutarate, remain a challenging problem for the viability of the proposed prebiotic cycle. As a class ...

BACKGROUND The oxidative dissolution of sulfide minerals, such as arsenopyrite (FeAsS), is of critical importance in many geochemical systems. A comprehensive understanding of their dissolution rates entails careful preparation of the mineral surface. Measurements of dissolution rates of arsenic from arsenopyrite are dependent on the size and degree of oxidation of its particles, among other fa...

Abstract Integrating structural control on mineralization and geochemical ore-forming processes is crucial when studying deformed ore deposits. Yet data are rarely acquired at the same scale: typically investigated from district to deposit macroscopic scales whereas described microscopic scale. The deciphering of a deformation–mineralization history valid every scale thus remains challenging. T...

Nitrate decreases sulfide release in wastewater treatment plants (WWTP), but little is known on how it affects the microzonation and kinetics of related microbial processes within the biofilm. The effect of nitrate addition on these properties for sulfate reduction, sulfide oxidation, and oxygen respiration were studied with the use of microelectrodes in microaerophilic wastewater biofilms. Mas...

Microorganisms were enumerated and isolated on selective solid media from a pilot-scale stirred-tank bioleaching operation in which a polymetallic sulfide concentrate was subjected to biologically accelerated oxidation at 45 degrees C. Four distinct prokaryotes were isolated: three bacteria (an Acidithiobacillus caldus-like organism, a thermophilic Leptospirillum sp., and a Sulfobacillus sp.) a...

Understanding how microorganisms influence the physical and chemical properties of the subsurface is hindered by our inability to observe microbial dynamics in real time and with high spatial resolution. Here, we investigate the use of noninvasive geophysical methods to monitor biomineralization at the laboratory scale during stimulated sulfate reduction under dynamic flow conditions. Alteratio...