Effect Of Fe2O3 Research Articles

Effect of Fe<sub>2</sub>O<sub>3</sub> on the Physical Property of Geopolymer Paste

Fe2O3 content affects the physical property of geopolymer paste made from waste materials. The effect of Fe2O3 was evaluated in this research. Geopolymer paste was made from the mixtures of mine tailing, melting slag, and alkali activator. Fe2O3 was added to discuss its effect with increasing the content. Compressive strength was 73.6 MPa without adding Fe2O3. But it was lowered to 32.5 MPa at the addition of 5wt. According to the analyzing results of XRD, SEM and EDS, Fe2O3 inhibited the geopolymer formation. Therefore, it is necessary to control the content of Fe2O3 to enhance the physical characteristics of geopolymer paste through the process of preparation.

Influence of Fe<sub>2</sub>O<sub>3</sub> on Molten Slag Properties in Slag Splashing on Nickel Smelting Converter

To predict the effect of Fe2O3 on slag splashing properties in the nickel smelting converter, Factsage software was used to calculate the proportion of the liquid phase and the viscosity for MgO-FeO-Fe2O3-SiO2 melts, the melting temperature was measured using slag column deformation, and the microstructure was also observed. The results show that, when the content of Fe2O3 is increased from 13.79% to 24.14%, the liquid phase at 1250°C maintains a high proportion of 82.68% and the melting temperature is below 1200°C; The magnetite and hortonolite with high melting points are considerably increased, and the viscosity rises accordingly. The melting and viscous properties for the slag with high content of Fe2O3 were improved by adding MgO. Desired slag splashed layer was formed with the saturated Fe2O3 and MgO slag.

Effect of Fe2O3 on properties and densification of 8YSZ by pulsed current activated sintering

Dense 8YSZ was sintered by pulsed current activated sintering (PCAS) within 1 minute from 8YSZ nanopowder prepared by a co-precipitation method. This sintering process was accomplished under the combined effects of a pulsed current and mechanical pressure. Highly dense 8YSZ was produced with a relative density as high as 96.5% under the simultaneous application of a 80 MPa of pressure and a pulsed current. The effects of an addition of Fe2O3 on the sintering behavior and ionic conductivities of the 8YSZ were also investigated.

Effect of Fe2O3 on the Sintering Property of MgO-CaO Refractory

The effect of Fe2O3 on the sintering property of MgO-CaO refractory was studied by XRD analysis and SEM analysis of sectioned specimens. As the content of ferric oxide increases, the specimen has higher density, lower porosity and the cold crush strength increases. In contrast the density and porosity of the fired specimens change slightly when the content is up to 6%. From XRD analysis, ferric oxide do not exist owing to that ferric oxide reacted with calcium oxide producing calcium ferrite; From SEM analysis, when the content of ferric oxide is 6%, calcium ferrite distributes uniformly between the main crystal phase and the matrix and the overall structure is homogeneous and dense. The result shows the nonuniform distribution of calcium ferrite as the content of ferric oxide is relatively low, while as the content of ferric oxide is high the excess amount of calcium ferrite existed in the sintered specimens will generate superfluous liquid phase to reduce the fire resistance of materials.

Phosphorus Gasification from Sewage Sludge during Carbothermic Reduction

The gasification process of phosphorus from municipal sewage sludge during carbothermic reduction process was investigated using a quadrupole mass spectrometer gas analysis and thermo-gravimetric analysis. Two types of sludge, with high and low Fe2O3 content, were used to evaluate the possible effect of Fe2O3 on the gasification behavior of phosphorus from sewage sludge during incineration processes. The gas species vaporized during the carbothermic reaction were measured by the quadrupole mass spectrometer with comparison to the ion currents for the respective molecular gas species. From the gas analysis, it was observed that PO and PO2 gas species were dominantly vaporized around 1073 K. Metallic phase phosphorus gas of P2 vaporized in the 1273–1700 K temperature range. The evolution of another metallic phase phosphorus gas of P4 was found to be negligibly small. Fe2O3 in the sludge has an important role in the phosphorus emission from the sludge during carbothermic reduction reaction, since metallic phosphorous gases react with the reduced iron and form Fe–P alloy.

Effect of Fe2O3 on the transport and magnetic properties of half metallic Fe3O4

We present a systematic study of the transport and magnetic properties of half metallic Fe3O4 films grown on Si (100) substrates with a Fe2O3 buffer layer using electron beam deposition technique. Transmission electron microscope images show the presence of small grains that are well separated by grain boundaries in our polycrystalline films. We observed that the Verwey transition does not appear for our Fe3O4 films and tunneling of spin polarized electrons across grain boundaries dominates the transport properties of the films. Magnetic measurements show a reduced magnetization in our films which does not saturate even at high fields. Coercivity of the films increases with decreasing temperature, suggesting the existence of additional anisotropy at low temperatures. Magnetoresistance curves show linear behavior at high fields which may be attributed to second order tunneling through intermediate states in the grain boundaries. At lower fields, the magnetoresistance behavior is governed by direct tunneling.

Effect of Fe2O3 on welding technology and mechanical properties of weld metal deposited by self-shielded flux cored wire

Effect of Fe2O3 on welding technology and mechanical properties of weld metal deposited by self-shielded flux cored wire

Effect of Fe2O3 doping on the electrical properties of a SnO2 based varistor

The effect of Fe2O3 addition on the densification and electrical properties of the (0.9895 − x) SnO2 + 0.01CoO + 0.005Nb2O5 + xFe2O3 system, where x = 0.005 or 0.01, was considered in this study. The samples were sintered at 1300°C for 2 h. Microstructure analysis by scanning electron microscopy showed that the effect of Fe2O3 addition is to decrease the SnO2 grain size. J × E curves indicated that the system exhibit a varistor behavior and the effect of Fe2O3 is to increase both, the non-linear coefficient (α) and the breakdown voltage (Er). Considering the Schottky thermionic emission model the potential height and width were estimated. Small amount addition of Fe2O3 to the basic system increases both the potential barrier height and width.

Direct Partial Oxidation (dpo) of Methane to Higher Hydrocarbons by Modified h-Zsm5 Catalyst

The oxidation of methane has been studied in a flow system as a function of the chemical composition of zeolite catalyst using nitrous oxide as oxidant. It is concluded that methanol is a primary oxidation product which may undergo further oxidation to formaldehyde and to carbon oxides. However, it may also undergo conversion over the acidic catalyst to higher hydrocarbons. Reaction with nitrous oxide resulted in the production of carbon oxides, methanol, formaldehyde, C2 - C4 , C5 - C7 nonaromatics, and aromatics. The effect of Fe2 O3 and Al2 O3 , with or without, over HZSM5 on products was studied.

Synthesis and Mechanical Properties of Mullite Developed from Beach Sand Sillimanite: Effect of Fe203

Mullite aggregate was developed from sillimanite beach sand and calcined alumina by the reaction sintering route using 1–4 wt% Fe2O3, as additive. Effect of Fe2O3, on the densification behaviour, microstructure and thermomechanical properties of the aggregate was discussed. It was found that Fe2O3 favours densification process by liquid phase formation, thereby deteriorating the thermomechanical properties particularly at higher sintering temperature. Mullite formed without Fe2O3 additive at 1600°C was mostly equiaxed in nature whereas it was needle shaped with few occasional equiaxed mullite grains within the matrix when formed in presence of Fe2O3 at 1500°C. Up to 4.08 wt% Fe2O3 enters into the mullite structure by solid solution formation at 1500°C.

Research in optical and thermal˗optical properties of alkaline amphibole asbestos

This paper deals with the researches of the main species of Chinese asbestos — winchite asbestos, calcium-magnesioriebeckite asbestos, and magnesioriebckite asbestos. Examination of them by various methods — crystallo-optical, thermo-optical, chemical and crystallochemical, X-ray, weight loss, infra-red absorption and statistics has given some principal results as follows : 1. Whether the various asbestos studied exhibit the purple-blue pleochroism and abnormal interference or not depends not only on the absorption of light of different wave lengths and extinction angles, but also on the content of Na. 2. The relation between Ng and the iron content of the magnesioriebeckite asbestos can be represented by the linear equation Fe/(Fe + Mg)(Mol%) = — 1 172.26 + 729.85 Ng. The effect of Fe₂O₃ on RI is greater than that of FeO and their regression formulas are given as : Ng = 1.30 × 10⁻³ × FeO + 3.21 × 10⁻³ × Fe₂O₃ + 1.611 5, Np = 1.46 × 10⁻³ × FeO + 3.27 × 10⁻³ × Fe₂O₃ + 1.599 9. 3. According to the changes in thermal-optical properties, the magnesioriebckite asbestos may be further subdivided into three stages, namely, magnesioriebeckite (< 550 °C), oxy-magnesioriebeckite (550-900 °C) and another mineral (> 900 °C). The critical point of optical property changes is found to be at about 550 °C.

含Fe<SUB>2</SUB>O<SUB>3</SUB>珪酸塩ガラスの赤外線吸収スペクトル

Infrared absorption spectra of silicate glasses containing Fe2O3 have been measured in order to find out the effect of Fe2O3 on the structure of silicate anion. In binary systems RO·Fe2O3 and R2O·Fe2O3, the peak shifts of absorption spectra Fe3+-O2− were studied in terms of the oxygen coordination number of Fe3+.The results indicate that the wave numbers of absorption peaks in Fe3+(oct.)-O2− and Fe3+ (tetr.)-O2− were about 580 cm−1 and 625∼660 cm−1, respectively. The oxygen coordination number of Fe3+ varied with the (RO, R2O)/Fe2O3 ratio and the basicity of RO, R2O·Fe3+ in octahedral sites was predominant for the acidic glasses. It was assumed that the oxygen coordination number of Fe3+ in silicate glasses varied with the basicity of silicate glasses, and Fe3+ (oct.) acted on silicate anion structure as a network modifier.

Effect of Fe2O3 on the 120° Phase Transition in BaTiO3 Single Crystals

Effect of Fe2O3 on the 120° Phase Transition in BaTiO3 Single Crystals