Abstract. Structural phase transitions of iron oxide (Fe 2 O) have been investigated at pressures up to 70 GPa and temperatures above 2500 K, using a laser …Web
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We studied three samples of Banded Iron Formation (BIF) rocks from Southern Granulite Terrane (SGT) of India, which was metamorphosed at high-pressure granulite facies and exhumed from 40 to 50 km depth. We examined the microstructure, texture, and deformation mechanisms of the primary minerals (quartz, magnetite, and …Web
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the high-pressure phase of hematite observed above B50GPa (refs. 1,4–12). For this phase two structures have been proposed by different groups: Rh 2O 3-II-type (space group Pbcn, no. #60)Web
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The objective of this work is to introduce garamite to enhance the stability of hematite-based invert emulsion mud under HPHT situations. The used garamite and hematite weighting material were ...Web
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Abstract and Figures. Structural studies and a full-profile refinement of the high-pressure phases of hematite (Fe2O3) were carried out to 76 GPa using x-ray synchrotron powder diffraction. It was ...Web
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Hematite assists in spine alignment and fracture healing. Hematite is one of the greatest stones for supporting excellent circulation in the body due to its lengthy history and high iron content. For millennia, it has been tied to blood. You should have this stone if you have high blood pressure, clotting, or heavy sweating.Web
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Section snippets Experimental. The sample of hematite used was commercially available iron(III) oxide, powder from Aldrich Corporation (product number 544884-25G) with a nominal average particle size 20–50 nm.Pressure was generated by a PE cell fitted with two toroidal anvils deforming a metallic gasket which contains a sample …Web
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High-pressure studies of hematite, α-Fe 2 O 3 ( Fig. 1a ), have attracted special attention due to their geophysical interest and the unclear role of Fe 3+ in the …Web
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in temperatures up to 653 K at ambient pressure. Hematite began to form at 653 K, all pyrite had transformed to hematite (H) at 688 K, and the hematite melted at 853 K. An increase in temperature ... High-pressure studies of pyrite are also interesting [2,14–17]. Pyrite is structurally stable to 55 GPa at static pressure and to 320 GPa in ...Web
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High pressure and temperature experiments on hematite and its polymorphs suggest that they can be dominant magnetic carriers down to ∼600 km depth, that is, in (cold portions of) subducted slabs (Ferré et al., 2021; Kupenko et al., 2019). Two dominant kinds of hematite, specular grains and red pigment, occur in soils and red beds.Web
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Also known as: Diiron xide, Hematite, High pressure experimental phase, Iron(III) oxide, Iron oxide (2/3).Web
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Polycrystalline hematite samples cored perpendicular and parallel to the foliation, i.e. perpendicular and parallel to a weak c-axis maximum, respectively, were deformed in triaxial compression experiments at confining pressures of 300 and 400 MPa, temperatures T between 600 and 1100 °C, and strain rates between 10 −4 and 10 −6 s …Web
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FAC damage can lead to under-deposit corrosion (UDC) problems in high-pressure (HP) ... (hematite [Fe 2 O 3] and iron oxide hydrate [FeOOH] rather than magnetite [Fe 3 O 4]). This might be ...Web
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Rozenberg G K, Dubrovinsky L S, Pasternak M P, Naaman O, Le Bihan T, Ahuja R (2002) High-pressure structural studies of hematite Fe 2 O 3, Physical Review B, 65, 064112 Shim S H, Duffy T S (2002) …Web
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FIG. 1 (color online). A schematic sketch of the states obtained. In the initial state (1), the system is in the low-pressure phase, very close to the transition, as shown by the x-ray measurements. The sample is then heated (20) and cooled again (3), and ruby pressure measurement shows the pressure did not change (pressure probably …Web
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The calculations predict that the high-pressure phase of magnetite (h-Fe 3 O 4) becomes unstable with respect to h-Fe 2 O 3 + FeO at pressures higher than 50 GPa. ... The thermodynamically predicted breakdown of magnetite to hematite and wüstite was not observed, but the trace amounts of hematite detected in the sample assemblage may …Web
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With increasing temperature and pressure, residual ferrihydrite was then transformed to hematite, or to goethite given the stabilizing effect of sorbed Si (Toner et al., 2012) as in our experiments with Si-coated biogenic Fe(III) mineral–cell aggregates. Thus, it is reasonable to consider BIF sediments as consisting of goethite (or hematite ...Web
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Request PDF | High-pressure phase transition of hematite, Fe 2O 3 | Structural phase transitions of iron oxide (Fe2O3) have been investigated at pressures up to 70 GPa and temperatures above 2500 ...Web
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But with those blood vessels narrowed, blood pressure increases. For the 122 million Americans with hypertension, decongestants can raise an already elevated …Web
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Hematite is the oldest known iron oxide mineral. Formula Fe2O3. it is the most important ore of iron because of its high iron content and its abundance. ... Hematite can be formed through contact metamorphism, which occurs when rocks are subjected to high temperatures and low-pressure conditions near igneous intrusions. The heat from …Web
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The observations, based on the behavior of a metastable high-pressure phase in the stability domain of the low- pressure phase, show that the electronic transition is preempted by the crystallographic transition, and the idea that the Electronic transition drives the transition in hematite is invalidated. We present a new method to separate the …Web
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Hematite aids in the alignment of the spine and fracture repair. Because of its long history and high iron content, hematite is one of the best stones for promoting good circulation in the body. It has been linked to blood for millennia. If you have high blood pressure, clotting, or excessive perspiration, this is a stone you should have in ...Web
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The mechanism of high pressure roll grinding on improvement of compression strength of oxidized hematite pellets was researched by considering their roasting properties. The results indicate that oxidized hematite pellets require higher preheating temperature and longer preheating time to attain required compression …Web
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hematite at high pressure. Hematite undergoes a transition at 50 GPa, and it is of importance to note that, close to that pressure, the transition is favored (either due toWeb
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Abstract. Structural studies and a full-profile refinement of the high-pressure phases of hematite (Fe2O3) were carried out to 76 GPa using x-ray synchrotron powder diffraction. It was found that pressure induces a progressive distortion of the corundum …Web
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Abstract. We studied electronic transport properties of hematite (α-Fe 2 O 3) at room temperature under cycling of high pressure up to ∼22 GPa. The original …Web
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specific surface area is as high as 1 723.0 cm2/g. 2.3 Methods of experiment The hematite concentrates prepared for experiments were ground by HPRG and ball mill grinding, respectively. The specification of high pressure roll is d 250 mm×120 mm, while the grinding (compression) pressure is 1 MP and the moisture content of iron concentrates is ...Web
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In addition, observations of hematite-magnetite assemblages in dehydrated serpentinites 20, 21 suggest a high fO 2, from one to five log units above the Quartz-Fayalite-Magnetite (QFM) oxygen ...Web
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