Initial rates of biological (Shewanella putrefaciens strain CN32, pH 6.8) and chemical (ascorbate, pH 3.0) reduction of synthetic Fe(III) oxides with a broad range of crystallinity and specific surface area were examined to assess how variations in these properties are likely to influence the kinetics of bacterial Fe(III) oxide reduction in heterogeneous natural Fe(III) oxide assemblages. The r...

Recent experimental studies permit development of conceptual and quantitative models of microbial Fe(III) oxide reduction at circumneutral pH that can be compared to and contrasted with established models of abiotic mineral dissolution. The findings collectively support a model for controls on enzymatic reduction that differs fundamentally from those applied to abiotic reductive dissolution as ...

OBJECTIVE Our goal of the study was to evaluate the antibacterial properties of endodontic sealers against the E. faecalis. MATERIALS AND METHODS Six millimeters wells were made for each material in all the preinoculated petri plates. Then, the petri plates were incubated for 24 h. The zones of inhibition appeared were measured, and the measurements were put to statistical analysis. RESULTS...

The Great Basin of the Western United States has thin continental crust and geologic structures that have controlled the emplacement of significant precious and base metal mineralization. Many of the mineral deposits in the Great Basin were emplaced by hydrothermal processes that altered the mineralogy of their host rock assemblages and facilitated concentration of metals. In the 1960’s and 197...

Nonpolar Bistable Resistive Switching Behaviors of Bismuth Titanate Oxide Thin Film Meng-Han Lin a , Ming-Chi Wu a , Chun-Chieh Lin b & Tseung-Yuen Tseng a c a Department of Electronics Engineering and Institute of Electronics , National Chiao Tung University , Hsinchu, 300, Taiwan b Department of Electrical Engineering , National Dong Hwa University , Hualien, 947, Taiwan c Department of Mater...

The chemistry textbooks tell us that uranium was discovered by the German chemist, Martin Heinrich Klaproth, in 1789, which is perhaps a simplification of the truth. The element was named after the planet Uranus and what Klaproth reported to the Royal Prussian Academy of Science in that year was uranium oxide, which he had separated from the heavy, black mineral known as pitchblende. The elemen...