Natural products with important therapeutic properties are known to be produced by a variety of soil bacteria, yet the ecological function of these compounds is not well understood. Here we show that phenazines and other redox-active antibiotics can promote microbial mineral reduction. Pseudomonas chlororaphis PCL1391, a root isolate that produces phenazine-1-carboxamide (PCN), is able to reduc...

DETERMINATION OF SILICA OXIDE iron ores usually are found in intimate association with sllica and phosphorus compounds. heir quantitative separation and purification sometimes present difficult problems to the chemist. Silicic acids may represent various degrees of dehydration. They are exceedingly weak, but combine with metallic oxides and form some of the most stable , oxides in nature, the s...

Despite obvious differences in morphology, substratum chemistry and the electrolyte in which they form, accumulations of iron corrosion products have the following characteristics in common: stratification of iron oxides/hydroxides with a preponderance of α-FeOOH (goethite) and accumulation of metals. Bacteria, particularly iron-oxidizing and sulfate-reducing bacteria have been identified in so...

Ferritin is a major iron storage protein. In case of iron deficiency, serum ferritin levels play a critical role in diagnosis and treatment.[1] Serum ferritin is an acute phase protein. Serum ferritin level is an indicator of body iron stores and may be normal or elevated in infective, inflammatory, or malignant disease.[2] Iron ions will be precipitated on the enamel surface as thin acid-resis...

The rate constants for in situ arsenic redox transformations in the surface waters of a eutrophic lake were estimated from observed horizontal heterogeneity in the arsenic species concentrations in the epilimnion of the Upper Mystic Lake. The smallest rate constants necessary to explain the observed horizontal heterogeneities were 10 times higher than rate constants estimated from monthly profi...

Iron–nickel spinel oxide NiFe2O4 nanoparticles have been prepared by the combination of chemical precipitation and subsequent mechanical milling. For comparison, their analogue obtained by thermal synthesis is also studied. Phase composition and structural properties of iron–nickel oxides are investigated by X-ray diffraction and Mössbauer spectroscopy. Their catalytic behavior in methanol deco...

Soluble iron in fine atmospheric particles has been identified as a public health concern by participating in reactions that generate reactive oxygen species (ROS). The mineralogy and oxidation state (speciation) of iron have been shown to influence fractional iron solubility (soluble iron/total iron). In this study, iron speciation was determined in single particles at urban and rural sites in...

To gain insight into factors that control H(2)O(2) persistence and ·OH yield in H(2)O(2)-based in situ chemical oxidation systems, the decomposition of H(2)O(2) and transformation of phenol were investigated in the presence of iron-containing minerals and aquifer materials. Under conditions expected during remediation of soil and groundwater, the stoichiometric efficiency, defined as the amount...

Iron (III) oxides are ubiquitous in near-surface soils and sediments and interact strongly with dissolved phosphates via sorption, co-precipitation, mineral transformation and redox-cycling reactions. Iron oxide phases are thus, an important reservoir for dissolved phosphate, and phosphate bound to iron oxides may reflect dissolved phosphate sources as well as carry a history of the biogeochemi...

Cosmetic Science Technology 2010 1 Abstract Borosilicate pigments represent a new variety in the wellknown class of pearlescent pigments. Consisting of transparent borosilicate flakes coated with high refractive metal oxides, e.g. titanium dioxide or iron oxides, these innovative pigments allow the achievement of optimum interference effects in combination with outstanding transparency. Borosil...