the present experiments is deciding to study the effect of hematite and volcanic ash on growth and physiological traits in sorghum factorial in a randomized complete design with  treatments and replications treatments consisted of volcanic ash concentrations (0, 0.25 and 0.5 g), hematite at three concentrations (0, 0.25 and 0.5 g), respectively. the results showed that the largest radicle and p...

Hematite and goethite are the two most abundant iron oxides in natural environments. Their formation is controlled by multiple environmental factors; therefore, their relative concentration has been used widely to indicate climatic variations. In this study, we aimed to test whether hematite and goethite growth is influenced by ambient magnetic fields of Earth-like values. Ferrihydrite was aged...

The effects of zinc and manganese on the reductive dissolution of hematite by the dissimilatory metal-reducing bacterium (DMRB) Shewanella putrefaciens CN32 were studied in batch culture. Experiments were conducted with hematite (2.0 g L 1) in 10 mM PIPES (pH 6.8), and H2 as the electron donor under nongrowth conditions (108 cell mL 1), spiked with zinc (0.02–0.23 mM) or manganese (0.02–1.8 mM)...

The Thermal Emission Spectrometer (TES) on the Mars Global Surveyor spacecraft has detected deposits of coarse-grained, gray crystalline hematite in Sinus Meridiani, Aram Chaos, and Vallis Marineris. We argue that the key to the origin of gray hematite is that it requires crystallization at temperatures in excess of about 100 ◦C. We discuss thermal crystallization (1) as diagenesis at a depth o...

Polymer concretes (PCs) were created by using varying concentrations of silica sand as aggregate and also hematite, colemanite and a commercial epoxy resin. Hematite is known to exhibit radiation shielding properties. Mechanical performance was evaluated including unit weight, pulse velocity, compressive strength, flexural strength, splitting tensile strength, modulus of elasticity and dynamic ...

In the present study, we investigated the adsorption of selenite [Se(IV)] onto hematite, which usually exists in soils and rocks, focusing on the effect of humic acid. The selenite adsorption onto hematite varied with the contact time, finally reaching an equilibrium state in 5 hours. The result was in good agreement with the Parabolic diffusion equation (R 2 = 0.97). The adsorption with differ...

The reductive dissolution of hematite (alpha-Fe2O3) was investigated in a flow-through system using AH2DS, a reduced form of anthraquinone-2,6-disulfonate (AQDS), which is often used as a model electron shuttling compound in studies of dissimilatory microbial reduction of iron oxides. Influent flow rate, pH, and Fe(II) and phosphate concentrations were varied to investigate the redox kinetics i...