适用于N_2／CO_2气源MgO－C供气元件的研究

对采用镁砂晶粒平均粒径在４００～６００ｕｒｎ，石墨纯度达到Ｃ≥９８％，石墨的细度在０．１４７～０．１７８ｍｍ，金属加入物以铝粉与硅粉复合形式加入，生产出的ＭｇＯ－Ｃ供气元件性能较好。同时研究了碳化硼和固体结合剂对该材质的抗氧化性和高温强度等的影响。     

高纯度天然烧结镁砂中杂质成分的分布

采用光学显微镜、扫描电子显微镜和能谱仪等研究了海城镁矿烧结镁砂的化学组成、显微结构及元素的分布，并由此推测出其质量情况。     

Influence of molar ratios on properties of magnesium oxychloride cement

A parametric study has been conducted to investigate the influences of the molar ratios of MgO/MgCl₂ and H₂O/MgCl₂ on the properties of magnesium oxychloride (MOC) cement. By an integrated assessment of the experimental studies of strength development and X-ray diffractograms, together with application of the relevant phase diagram, it is recognized that the molar ratios of MgO/MgCl₂ and H₂O/MgCl₂ can significantly affect the properties of MOC cement. For a MOC cement paste possessing a dominance of 5MgO·MgCl₂·8H₂O (phase 5) crystals, the molar ratios of MgO/MgCl₂ of 11-17 and H₂O/MgCl₂ of 12-18 are found to be the most favorite ranges for design purpose. The choose of the molar ratio of H₂O/MgCl₂ is, however, largely depends on the molar ratio of MgO/MgCl₂ mainly for controlling workability of paste. Therefore, the most critical parameter to be selected in the design process is the molar ratio of MgO/MgCl₂, although the reactivity of the MgO powder is also important. Besides, the molar ratio can also be affected by the reactivity of the MgO powder to be employed. It is believed that a molar ratio of MgO/MgCl₂ of 13, the most suitable one shown in this study, can be used as a starting point in the normal practice.     

Preliminary Study on MgO.Al2O3 Spinel Fiber

1IntroductionMgO·Al2 O3spinelisanimportantceramicmaterialextensivelyusedinrefractoriesindustry ,especiallyforapplicationsathightemperaturecriticalareaswherether malshockresistanceandslagpenetrationresistanceareprimaryrequisites[1] .ButlittleinformationaboutMgO·Al2 O3spinelfibershasbeenreportedinliterature .Inthiswork ,itisfoundthatwhenpressedspecimenscomposedofpulverizedMg Al Omaterialwithappropriateoxide metalratioarefiredat 15 0 0℃for 6hoursundercon trolledatmosphere ,MgO·Al2 O3spi…     

Metal-organic framework-derived Mg-Zn hybrid nanocatalyst for biodiesel production

Controlled synthesis of metal–organic framework (MOF)-derived Mg-Zn hybrid nanostructure was demonstrated for the development of basic catalysts applied in biodiesel production from soybean oil. Two types of Mg-Zn hybrid nanostructures were successfully fabricated under different atmospheres (Ar, air), (1) MgO nanoparticles encapsulated in Zn-based MOF (MgO@Zn-MOF) and (2) MgO nanoparticles uniformly decorated on ZnO nanoparticles derived from Zn-MOF (MgO@ZnO), respectively. Ultrafine MgO nanoparticles (<5 nm for MgO@Zn-MOF and ≈10 nm for MgO@ZnO) were successfully synthesized and homogeneously dispersed in the MOF-derived Mg-Zn hybrid nanostructures. Significant increases in the specific surface area (i.e., a maximum of 1048.5 m²/g) and corresponding basicity (i.e., by a maximum of 2.1 times) were achievable by using MOF-based strategy comparing to the Mg-Zn catalyst prepared by a conventional solution-based approach. High 3-cycle stability and high yields of fatty acid methyl esters at a stoichiometric feed ratio 3 were both achievable, 67.6% and 73.3%, by using MgO@Zn-MOF and MgO@ZnO as the catalysts, respectively. The work demonstrates a prototype study of utilizing MOF to develop high-performance basic nanocatalysts through fundamental understanding of material synthesis by design versus their corresponding activities.     

MgO对原位烧结含锆莫来石材料性能影响的研究

初步研究了氧化镁对原位烧结含锆莫来石陶瓷性能的影响,经XRD分析表明:由于氧化镁的引入,在材料烧结过程中,有部分镁铝尖晶石的形成,同时在原位状态下也能形成部分Mg稳定的ZrO2,这对于形成氧化锆/镁铝尖晶石/莫来石热梯度晶相组成以减缓热应力十分有利,而且随着氧化镁加入量的增大,镁铝尖晶石、四方相氧化锆形成的量增多;并研究了材料抗热震系数达到最佳时的氧化镁加入量。     

含锆复合相结合镁砖的研究

以电熔镁砂、烧结镁砂、锆英砂、自制添加剂、结合剂为基本原料，通过合理级配、高温烧结研制了适用于水泥窑、玻璃窑的新型含锆复合相结合镁质耐火材料。该材料由方镁石、镁铝尖晶石、镁橄榄石、二氧化锆以及含二氧化锆的复合相组成。材料的荷重软化温度T0.6＞1600℃、热震稳定性（1100℃-水冷）＞5次、抗玻璃液碱蒸汽侵蚀试验（ASTM-987-83）判为二级、抗水泥熟料液相侵蚀、有优异的挂窑皮特征。该材料已分别在浮法窑、垂直引上窑、新型大中型干法窑上进行应用试验，取得了良好效果。     

有关新型绿色环保补炉料发展的综述

冶炼任务不断加重,提高补炉材料质量以便最大限度缩短转炉补炉占用时间尤为重要。同时,节能减排、环境保护是企业面临的重要任务。传统补炉料采用热拌工艺,即镁砂加热后与沥青热态混合搅拌,这种工艺污染严重,生产效率低,工艺复杂,难以满足补炉需求。以电熔镁砂为转炉生产原料,采用新型材料水基粘合剂为结合剂,并对生产工艺进行了一系列的改进,实现了电熔镁砂补炉料的生产,操作过程中实现了“高温快补”且无烟雾产生。绿色环保补炉料的应用,从根本上解决了传统补炉料所带来的烧结时间长,环境污染严重等难题,具有重要历史意义。     

Scavenging effect on ionic conduction behaviour at the grain boundary of MgO partially stabilised zirconia

The scavenging effect of magnesium oxide (MgO) addition on electrical property of 9 mol-% MgO partially stabilised zirconia (Mg-PSZ) was investigated in terms of phase transformation and intergranular phase formation. The addition of MgO up to 5 mol-% caused a stabilisation of Mg-PSZ, which led to an increase in the cubic phase and a decrease in the monoclinic and tetragonal phases in Mg-PSZ. The Mg-PSZ with the addition of 5 mol-% of MgO also exhibited the maximum ionic conductivity (0.3915?S?cm^?1 at 1500°C) and forsterite (Mg₂SiO₄) was observed on the grain boundaries of Mg-PSZ. The intergranular phases, formed by reactions between the silicon in Mg-PSZ and MgO addition, reduced the grain boundary resistance, because the siliceous phase which is a hindrance for oxygen ion conduction was scavenged by the formation of Mg₂SiO₄.     

TiO_2对镁铬砖抗渣蚀性的影响

利用XRD分析和光学显微镜等测试手段 ,研究了添加TiO2 对镁铬砖抗渣蚀性的影响。结果表明 :炉渣中的CaO能分解镁铬砖中的二次尖晶石而使镁铬砖损毁 ,但加入TiO2 后 ,TiO2 能优先于尖晶石中的Cr2 O3与渣中CaO反应 ,生成高熔点的CaTiO3,从而抑制CaO对砖中镁铬尖晶石的分解 ,提高了镁铬砖的抗高钙渣渣蚀能力