Fe_2O_3对阿利特-硫铝酸盐水泥性能影响的初步研究

文章探讨了Fe2O3对阿利特-硫铝酸盐水泥熟料矿物形成及性能的影响,结果表明,适量的Fe2O3可改善生料的易烧性,促进f－CaO的吸收,促进C3S及C4A3S两种主要矿物的形成并提高水泥的强度;当Fe2O3含量较高时,则不利于C3S与C4A3S的形成且使水泥的强度降低,凝结时间延长。     

矿渣阿利特—硫铝酸盐水泥性能的研究

探讨了高炉矿渣及石膏和石灰石参与下阿利特－硫铝酸盐水泥的性能。结果表明，在阿利特－硫铝酸盐水泥熟料中掺加较多量矿渣，强度的降低幅度较小，当前适量的石膏及石灰石存在时，水泥的７ｄ，２８ｄ强度可赶上或超过不掺矿渣的试样。这一结果归结为所造成的ＡＦｔ生长的良好条件及对矿渣的良发激发作用以及对硅酸盐矿物水化的促进作用；掺加矿渣，水泥的凝结时间有所延长。     

阿利特—硫铝酸盐水泥与硅酸盐水泥复合性能的研究

研究了阿利特－硫铝酸盐水泥与硅酸盐水泥复合所制备的水泥的性能。结果表明,复合后水泥的强度性能优于单一品种水泥的性能;凝结时间则由复合体中占比例较多的一种水泥所控制。     

Fe2O3对阿利特-硫铝酸盐水泥熟料矿物形成影响的研究

以纯化学试剂配料,研究了Fe2O3对阿利特－硫铝酸盐水泥熟料矿物形成的影响。结果表明,低温下煅烧,Fe2O3不利于系统中fCaO的吸收;高温下煅烧,一定量的Fe2O3可促进C3S及C4A3S^-矿物的形成,有利于其在熟料中的共存;而当Fe2O3含量较高时,将会阻碍C3S的形成及降低C4A3S^-的含量。     

MgO对阿利特—硫铝酸盐水泥熟料矿物形成及性能影响的研究

研究了ＭｇＯ对阿利特－硫铝酸盐水泥熟料矿物形成及性能的影响。结果表明，含有适量的ＭｇＯ可改善生料的易烧性，促进ｆＣａＯ的吸收，促进Ｃ３Ｓ及Ｃ４Ａ３Ｓ两种主要矿物的形成，有利于其在熟料中的共存；适量的ＭｇＯ亦可提高水泥的强度；阿利特－硫铝酸盐水泥熟料中可允许有较高的ＭｇＯ存在，使高镁原料的利用成为可能。     

TiO2对阿利特-硫铝酸盐水泥性能影响的研究

以工业原料配料，在实验室研究了TiO2对阿利特-硫铝酸盐水泥熟料煅烧、矿物形成及水泥性能的影响。结果表明，（1）对于含C3S较高的熟料，埘（TiO2）〈1％，TiO2有利于熟料的烧结，改善生料的易烧性，促进产f-CaO的吸收，促进C3S及C45两种主要矿物的形成；当TiO2含量超过1％时f-CaO升高，C3S及C4A3S^-的形成量降低。（2）掺入1％TiO2时，可提高水泥各龄期强度；当TiO2含量超过1％时，会显著延长水泥的凝结时间。     

石膏对阿利特─硫铝酸盐水泥性能的影响

研究了石膏对阿利特─硫铝酸盐水泥强度、凝结时间、干缩性等性能的影响。结果表明，掺加５％左右的石膏，可显著提高水泥强度，当掺量达约８％时，水泥的早期强度降低，更多的石膏则造成水泥安定性不良；石膏可延长水泥的凝结时间；存在适量石膏，水泥的干缩值减小。     

碱对阿利特－硫铝酸盐水泥熟料矿物形成及水泥性能的影响

以石灰石、粉煤灰、粘土、石膏等为原料,研究了 K2O、 Na2O对阿利特－硫铝酸盐水泥熟料矿物形成及性能的影响。结果表明,少量碱能改善水泥生料的易烧性,促进 fCaO的吸收,过多的碱使 C4A3矿物难以形成;当碱掺加量约 1 2％时, Na2O有利于 C3S矿物的形成,并提高水泥的早期强度,而 K2O则使 C3S的形成量减少,水泥的强度降低;掺加碱使水泥的凝结时间延长。     

消息二则

文章探讨了Fe2O3对阿利特一硫铝酸盐水泥熟料矿物形成及性能的影响,结果表明,适量的Fe2O3可改善生料的易烧性,促进f-CaO的吸收,促进C3S及C4-A3S两种主要矿物的形成并提高水泥的强度;当Fe2O3含量较高时,则不利于C3S与C4A3S的形成且使水泥的强度降低,凝结时间延长.     

The behaviour of Ru/Fe2O3 catalysts and Fe2O3 supports in the TPR and TPO conditions

The texture of Fe₂O₃ support and Ru/Fe₂O₃ catalysts supported on iron oxides obtained from β-FeOOH (B) or δ-FeOOH (D) and their catalytic activity in WGSR were studied. Also their susceptibilities to reduction and reoxidation, were studied by TPR, using H₂ or CO and TPO methods. In the case of TPR_CO the composition of the reducing mixture containing traces of H₂O enabled investigation of water gas shift reaction (WGSR).

The catalysts from series D were found more readily reducible and oxidised than those from series B. The supported ruthenium enhanced the redox effects and caused the appearance of additional effects related directly to its presence. Depending on the kind of support and on ruthenium presence considerable differences in temperatures of WGSR onset were found. It is suggested that the susceptibility of the catalysts to reduction and oxidation is responsible for their activity in the WGSR.     

Fe2O3掺杂对氧化锌线性电阻的影响

利用固相烧结法制备出基础配方为ZnO–A1₂O3–MgO–TiO₂–SiO₂–Fe2O3的ZnO线性电阻。研究了Fe₂O₃掺杂量对ZnO线性电阻微观结构、阻温特性和阻频特性的影响。结果表明:当Fe₂O₃掺杂量为0.75%(质量分数)时,氧化锌线性电阻的非线性系数为1.1₂,阻温系数取得–8.23×10^–3/℃,此时样品的综合性能最好。     

Effect of TiO2 supporting layer on Fe2O3 photoanode for efficient water splitting

For an electrochemical water splitting system, titanate nanotubular particles with a thickness of ∼700 nm produced by a hydrothermal process were repetitively coated on fluorine-doped tin oxide (FTO) glass via layer-by-layer self-assembly method. The obtained titanate/FTO films were dipped in aqueous Fe solution, followed by heat treatment for crystallization at 500 °C for 10 min in air. The UV–vis absorbance of the Fe-oxide/titanate/FTO film showed a red-shifted spectrum compared with the TiO₂/FTO coated film; this red shift was achieved by the formation of thin hematite-Fe₂O₃ and anatase-TiO₂ phases verified using X-ray diffraction and Raman results. The cyclic voltammetry results of the Fe₂O₃/TiO₂/FTO films showed distinct reversible cycle characteristics with large oxidation–reduction peaks with low onset voltage of I–V characteristics under UV–vis light illumination. The prepared Fe₂O₃/TiO₂/FTO film showed much higher photocurrent densities for more efficient water splitting under UV–vis light illumination than did the Fe₂O₃/FTO film. Its maximum photocurrent was almost 3.5 times higher than that obtained with Fe₂O₃/FTO film because of the easy electron collection in the current collector. The large current collection was due to the existence of a TiO₂ base layer beneath the Fe₂O₃ layer.     

基于氧化铁/生物质碳复合材料的高性能超级电容器研究

为改善碳材料比电容低的问题以及氧化铁（Fe₂O₃）导电性和循环稳定性差的问题,采用氧化铁修饰生物质衍生碳（ATC）表面制备氧化铁/生物质碳（Fe₂O₃/ATC）复合材料,通过氧化铁和生物质衍生碳的协同效应使复合材料获得更高的比电容和更好的稳定性。利用扫描电镜（SEM）、X射线光电子能谱（XPS）、拉曼（Raman）光谱等技术手段对样品进行了表征。结果表明,制备的复合材料存在一定的孔隙结构,氧化铁纳米粒子被锚定在碳表面。当氧化铁和生物质衍生碳的质量比为1:1时,制备的复合材料具有最优的电化学性能,在3.0 mol/L氢氧化钾溶液中显示出430.8 F/g（电流密度约为1.0 A/g）的高比电容,电流密度增大20倍时电容保持率大于60%。将其作为负极构建的不对称超级电容器具有较高的电压窗口（0~1.6 V）,并且实现了39.1 W·h/kg的高能量密度;同时表现出优异的循环稳定性,在电流密度为10 A/g下循环5 000次后拥有111%的电容保持率。     

酶诱发均匀沉淀法制备纳米Fe2O3

以硝酸铁和尿素为原料,草酸为掩蔽剂,室温下采用脲酶催化分解尿素诱发均匀沉淀,制备了纳米氧化铁前驱物.经TG-DTA,FTIR,XRD等测试表明,前驱物经热处理(500 ℃,2 h)后,可得到α-Fe     

Corrosion mechanisms of Al2O3/MgAl2O4 by V2O5, NiO, Fe2O3 and vanadium slag

The effects of V₂O₅, NiO, Fe₂O₃ and vanadium slag on the corrosion of Al₂O₃ and MgAl₂O₄ have been investigated. The specimens of Al₂O₃ and MgAl₂O₄ with the respective oxides above mentioned were heated at 10 °C/min from room temperature up to three different temperatures: 1400, 1450 and 1500 °C. The corrosion mechanisms of each system were followed by XRD and SEM analyses. The results obtained showed that Al₂O₃ was less affected by the studied oxides than MgAl₂O₄. Alumina was only attacked by NiO forming NiAl₂O₄ spinel, while the MgAl₂O₄ spinel was attacked by V₂O₅ forming MgV₂O₆. It was also observed that Fe₂O₃ and Mg, Ni, V and Fe present in the vanadium slag diffused into Al₂O₃. On the other hand, the Fe₂O₃ and Ca, S, Si, Na, Mg, V and Fe diffused into the MgAl₂O₄ structure. Finally, the results obtained were compared with those predicted by the FactSage software.     

The system CaOAl2O3Fe2O3 with added fluoride flux

Effects of fluoride fluxes, especially CaSiF₆·2H₂O upon phase equilibria in the system CaOAl₂O₃Fe₂O₃ are described, presenting liquidus data, new phase field boundaries and invariant points and solid solution areas. The primary phase field for C_12?xA₇·CaF₂ is increased substantially in size, and liquidus or invariant temperatures are depressed by amounts ranging from 20 to 80°C.     

Effect of Fe2O3 doping on colour and mechanical properties of Y-TZP ceramics

Yttria-stabilized zirconia (Y-TZP) samples with different Fe concentrations were prepared aiming to study the effects of Fe₂O₃ doping on colour and mechanical properties. Since colour is an important optical property for jewellery and watchmaking, the investigation of colour in zirconia ceramics has a great scientific and technological interest. An investigation of the mechanical and optical properties, specifically the colour, was developed starting from commercial partially yttria-stabilized zirconia (Y-TZP) powders produced by Emulsion Detonation Synthesis (EDS). Within the strategies to get colours, the use of colouring oxides such as iron oxide (Fe₂O₃) was the chosen approach. The addition of specific ions into the ZrO₂ matrix can be used to tune zirconia colour without compromising its outstanding mechanical properties. Doping with iron oxide has proved to be a suitable, reproducible and irreversible colouring mechanism, allowing the development of a chromatically beige stable material with respect to its use in different processing conditions such as different atmospheres and temperature ranges. XRD results suggested that iron ions dissolved into tetragonal zirconia phase are at interstitial positions since the unit-cell volume of the tetragonal zirconia increases with increasing iron content. The effect of dopant addition on the mechanical properties of Y-TZP ceramics was also assessed. Compared to the undoped samples, doped ones exhibit a similar Vickers hardness (>1200?MPa) and biaxial flexural strength (>1000?MPa). However, it was observed that Fe₂O₃ doping slightly decreased the fracture toughness of Y-TZP ceramics.     

纳米A12O3改性聚四氟乙烯力学性能的研究

通过压制和烧结，制备了纳米Al2O3改性聚四氟乙烯(PTFE)，并研究了改性PTFE的物理机械性能。结果表明：纳米Al2O3粒子对PTFE有显著的增强作用，提高了复合材料的拉伸强度和硬度；降低了摩擦系数，但也使复合材料的断裂伸长率降低。