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Effects of mgsio3 on the crystal growth and characteristics of type-Ib gem quality diamond in Fe-Ni-C system

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Chinese Physics B 2020年第12期29卷 511-518页

作者：鲁智云王永奎房帅蔡正浩赵占东王春晓马红安陈良超贾晓鹏 State Key Laboratory of Superhard Materials College of PhysicsJilin UniversityChangchun 130012China Key Laboratory of Materials Physics of Ministry of Education School of PhysicsZhengzhou UniversityZhengzhou 450001China

We report the effects of mgsio3 addition on the crystal growth and characteristics of type-Ib diamonds synthesized in Fe–Ni–C system. The experiments were carried out with pressure at 5.5 GPa, temperature at 1385℃–1405℃, and duration of 23.1 h. As mgsio3 increases from 0.0 wt% to 3.0 wt%, the diamond growth temperature increases from1385℃ to 1405℃, the addition of mgsio3 and the movement of P–T diagram toward the higher temperature direction result in a series of effects to the Fe–Ni–C system and crystal growth. Firstly, it increases the content of metastable recrystallized graphite and accelerates the competition with the carbon source needed for diamond growth, thus causing the decreased crystal growth rate. Diamond crystals exhibit the combination form of {111}, {100}, {113}, and {110}sectors, the decreased {100} and {113} sectors, dominated {111} sector are all attributed to the higher growth rate in [100]direction caused by the synergy of mgsio3 and the movement of P–T diagram. The higher growth rate in [100] direction also increases the metal catalyst and graphite inclusions and leads to the increase of residual tensile stress on the crystal surface. Accompanying with the high growth rate, a higher dissolution rate along [100] and [113] directions than [111]direction occurs at the microstructure and forms the significantly developed(111) stepped growth layer. In addition to the movement of P–T diagram, the addition of mgsio3 poisons the catalyst and increases the nitrogen content of diamond from 120 ppm to 227 ppm.

关键词： diamond mgsio3 nitrogen content recrystallized graphite

下地幔条件下钙钛矿结构mgsio3熔化行为的研究（英文）

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Chinese Journal of Chemical Physics 2006年第4期19卷 311-314+375页

作者：刘子江孙小伟杨向东程新路吴海英兰州师范高等专科学校电子信息科学与技术研究所兰州交通大学数理学院四川大学原子与分子物理研究所四川大学原子与分子物理研究所兰州 730070 四川大学原子与分子物理研究所成都 610065

利用分子动力学方法结合有效的对势,模拟了下地幔条件下钙钛矿结构mgsio3的熔化曲线．研究表明,分子动力学模拟结果精确地再现了广泛压强范围内钙钛矿结构mgsio3的状态方程,并且熔化曲线与最新的实验结果也符合的很好．在压强上升到下... 详细信息

利用分子动力学方法结合有效的对势,模拟了下地幔条件下钙钛矿结构mgsio3的熔化曲线．研究表明,分子动力学模拟结果精确地再现了广泛压强范围内钙钛矿结构mgsio3的状态方程,并且熔化曲线与最新的实验结果也符合的很好．在压强上升到下地幔压强范围内,压强低于60 GPa时的钙钛矿结构mgsio3熔化曲线比较陡,接着变得平缓．在核幔边界压强135 GPa时,钙钛矿结构mgsio3的熔化温度是6500 K,明显低于Zerr和Boehler实验结果的外推结果．

关键词：熔化曲线分子动力学高压 mgsio3

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下地幔条件下mgsio3钙钛矿的物性研究

下地幔条件下MgSiO3钙钛矿的物性研究

作者：聂新卫武汉理工大学

学位级别：硕士

高温高压物理是研究高温高压极端条件下物质行为的一门学科,在高压极端条件下,物质会表现出迥异的力、热、电、光等性质。地幔的热力学对流与地幔的组分和运动状态密切相关。但是以人们目前的技术而言,还不能直接获取地幔物质进行研究,... 详细信息

高温高压物理是研究高温高压极端条件下物质行为的一门学科,在高压极端条件下,物质会表现出迥异的力、热、电、光等性质。地幔的热力学对流与地幔的组分和运动状态密切相关。但是以人们目前的技术而言,还不能直接获取地幔物质进行研究,只能通过其它方法反演地幔尤其是下地幔的物质组成。而高温高压技术能够模拟地球内部温度和压强环境,为探索地球深部的物质组成提供了重要的方法和途径。根据地球物理、地球化学、矿物学等方面的研究,现已公认下地幔的主要物质是硅酸镁钙钛矿,化学式为(Mg,Fe,Fe)(Si,Al)O,因此硅酸镁钙钛矿的状态方程和热弹性参数的研究对于限定下地幔的矿物组分和温度分布是非常必要的。尽管硅酸镁钙钛矿中含有FeO、FeO,和AlO等多种组分,但是mgsio所占比例高达90mol%。因此纯mgsio钙钛矿的状态方程和热弹性的研究对于限定下地幔的矿物具有重要意义。尽管通过动高压实验、静高压实验、理论计算对mgsio状态方程进行了大量研究,但是仍存在争议,导致地幔模型存在很大的不确定性。本文选取mgsio作为研究对象,使用大腔体压机烧结的高纯mgsio顽火辉石作为实验的初始样品。利用动高压实验技术,在80-140GPa冲击压力的条件下测量其状态方程数据。并提出了新的数据处理和分析方法,使得mgsio的动静高压实验数据达到自洽。新的方法的提出不但为动高压下mgsio的高压相变提供了有力判据,更重要的是为高压下钙钛矿相mgsio的状态方程准确获得提供了重要支持。本文根据的动高压实验数据结合前人的实验结果,分析了下地幔温度和压强环境下钙钛矿相mgsio的状态方程和绝热体积模量,并与根据地震波数据给出的PREM模型进行了对比,为限定下地幔中mgsio的含量提供了重要参考。论文主要创新性工作包括以下三个方面:1、首次以高纯MgO和SiO粉末为原料,人工合成高纯度的mgsio顽火辉石样品作为高压实验原料进行高压实验并得到实验数据。2、提出一种新的方法来分析高压下的Hugoniot状态方程数据,得到初始状态为高压相的Hugoniot状态方程。重新得出的Hugoniot参数为:C=7.973km/s,λ=1.321,热力学参数K和K’与静高压结果非常一致。这进一步说明动静高压试验测量结果是自洽的。3、根据得出的Hugoniot状态方程计算出下地幔温压环境下mgsio钙钛矿的物态方程,并与PREM模型进行了比较,发现纯mgsio钙钛矿的密度小于下地幔的密度。说明下地幔中应该含有原子量大于Mg的元素,很可能是Fe。至于Fe是以FeO,还是以(Mg,Fe)SiO的方式存在,或者两种方式都有,还需要进一步的理论和实验研究。

关键词：下地幔钙钛矿 mgsio3 高温高压状态方程

A comparative study of proliferation and osteogenic differentiation of rat adipose-derived stem cells in β-tricalcium phosphate (β-TCP), forsterite (Mg_2SiO_4 ) and clinoenstatite (mgsio_3)

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Chinese Science Bulletin 2013年第24期58卷 3033-3042页

作者： LENG Bin JIN XiaoGang LIN QiuXia CHEN Lei WANG Yan DU ZhiYan LIN KaiLi CHANG Jiang GU XiaoMing WANG ChangYong Department of Implantology of People's Armed Police General Hospital Department of Advanced Interdisciplinary Studies Institute of Basic Medical Sciences and Tissue Engineering Research Center Academy of Military Medical Sciences State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of Ceramics Chinese Academy of Sciences

In this study, the effects of forsterite and clinoenstatite powder extracts on the proliferation and osteogenic differentiation of rat adipose-derived stem cells (ASCs) were investigated and compared with the β-tricalcium phosphate (β-TCP) powder extracts. Methylthiazolyldiphenyl-tetrazolium bromide (MTT) assay and live-dead staining were performed to evaluate the viability and proliferation of rat ASCs. Osteogenic differentiation of rat ASCs were assayed by alkaline phosphatase (ALP) staining and ALP activity test. The expression of osteogenic marker genes (alkaline phosphatase (ALP), runt related transcription factor 2 (Runx2), collagen type Iα1 (Col1α1), secreted phosphoprotein1 (Spp1, osteopontin), integrin binding sialoprotein (Ibsp), bone gla protein (Bglap)) were detected by real-time polymerase chain reaction (PCR). The MTT assay and the live-dead staining showed that all the three ceramics possessed good cytocompatibility with rat ASCs. Furthermore, forsterite and clinoenstatite promoted the proliferation of rat ASCs compared with β-TCP. The results of the ALP activity test and the real-time PCR demonstrated that forsterite and clinoenstatite promoted the osteogenic differentiation of rat ASCs. These results suggested that forsterite and clinoenstatite are bioactive ceramics that may be used for preparation of bone tissue engineering (BTE) scaffolds.

关键词：脂肪干细胞成骨分化细胞增殖镁橄榄石 TCP相磷酸三钙 Mg2SiO4 mgsio3

硅酸镁（mgsio3）协效剂对膨胀阻燃聚丙烯材料性能影响

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辽宁化工 2019年第7期48卷 622-624页

作者：高苏亮张惠鲍文波季洋林峰黑龙江省润特科技有限公司研发中心黑龙江佳木斯154004

选择硅酸镁作为协效剂,用在膨胀阻燃剂中,然后制备了膨胀阻燃聚丙烯(PP)材料,探讨了硅酸镁对膨胀阻燃剂聚丙烯材料的协效作用。结果表明,膨胀阻燃剂中加入硅酸镁后,聚丙烯材料的的阻燃性能明显提高,1.6 mm样条达到UL94V-0级,材料的极限... 详细信息

选择硅酸镁作为协效剂,用在膨胀阻燃剂中,然后制备了膨胀阻燃聚丙烯(PP)材料,探讨了硅酸镁对膨胀阻燃剂聚丙烯材料的协效作用。结果表明,膨胀阻燃剂中加入硅酸镁后,聚丙烯材料的的阻燃性能明显提高,1.6 mm样条达到UL94V-0级,材料的极限氧指数值为34.5%,硅酸镁对阻燃聚丙烯材料的力学性能影响小。热重分析表明,硅酸镁可以催化酯化反应,促进成炭,提高了聚丙烯材料的热稳定性。

关键词：协效作用 mgsio3 膨胀阻燃剂 PP

大块钙钛矿mgsio_3和镁方铁矿(Mg,Fe)O的高压合成

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高压物理学报 2006年第4期20卷 391-396页

作者：张莉龚自正费英伟西南交通大学高温高压物理研究所四川成都610031 华盛顿卡内基研究院地球物理实验室美国华盛顿20015

钙钛矿相mgsio3和镁方铁矿(Mg,Fe)O作为地球下地幔含量最丰富的候选矿物,其高温高压实验数据通常用来与地震学探测数据做对比,对限定下地幔的真实矿物学组分具有决定性的作用。但天然的钙钛矿相mgsio3和镁方铁矿(Mg,Fe)O很难得到,给这... 详细信息

钙钛矿相mgsio3和镁方铁矿(Mg,Fe)O作为地球下地幔含量最丰富的候选矿物,其高温高压实验数据通常用来与地震学探测数据做对比,对限定下地幔的真实矿物学组分具有决定性的作用。但天然的钙钛矿相mgsio3和镁方铁矿(Mg,Fe)O很难得到,给这两种矿物的高温高压实验研究工作带来不便。介绍了应用活塞圆筒(Piston-Cylinder)压机和大腔体二级压砧(Mutli-Anvil)压机高温高压合成大块钙钛矿相mgsio3和不同Fe/Mg比的镁方铁矿(Mg,Fe)O样品的实验技术和实验方法,对所得到的样品进行了微区电子探针、拉曼光谱和X射线衍射分析。所得样品可以作为高压实验特别是冲击压缩实验的初始样品。

关键词： mgsio3 钙钛矿 (Mg,Fe)O镁方铁矿高温高压二级压砧合成

红土镍矿中mgsio_3在NaOH亚熔盐体系中的浸出反应机理

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中国有色金属学报 2015年第1期25卷 197-202页

作者：赵昌明翟玉春王国承艾新港辽宁科技大学材料与冶金学院鞍山114051 东北大学材料与冶金学院沈阳110004

根据硅镁型红土镍矿中镁硅酸盐存在形式,采用化学沉淀法合成Mg Si O3,通过正交实验考察反应温度、反应时间、液固比和Na OH浓度对Mg Si O3在Na OH亚熔盐体系中的浸出过程的影响,得出优化实验条件为:反应温度为210℃,反应时间为180min,... 详细信息

根据硅镁型红土镍矿中镁硅酸盐存在形式,采用化学沉淀法合成Mg Si O3,通过正交实验考察反应温度、反应时间、液固比和Na OH浓度对Mg Si O3在Na OH亚熔盐体系中的浸出过程的影响,得出优化实验条件为:反应温度为210℃,反应时间为180min,液固比为6:1,Na OH浓度为80%。在优化实验的基础上,采用Raman光谱对反应过程进行在线检测,利用XRD和IR光谱分析反应后的水浸渣结构变化,解析Mg Si O3在Na OH亚熔盐体系中的反应机理。结果表明:在反应过程中,Si O4中的Si—O被破坏,Na OH介入硅酸盐晶格中,其中间产物为Mg2Si O4和Na2Mg Si O4,Mg2+经过碱浸过程可以脱离Si O4阵列,以Mg(OH)2形式从其硅酸盐中得以释放。

关键词： mgsio3 拉曼光谱亚熔盐浸出反应机理

Theoretical calculation of equilibrium Mg isotope fractionation between silicate melt and its vapor

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Acta Geochimica 2018年第5期37卷 655-662页

作者： Haiyang Luo Huiming Bao Yuhong Yang Yun Liu State Key Laboratory of Ore Deposit Geochemistry Institute of Geochemistry Chinese Academy of SciencesGuiyang 550081 China University of Chinese Academy of Sciences Beijing 100049China Department of Geology and Geophysics Louisiana StateUniversity Baton Rouge LA 70803 USA Center for Lunar and Planetary Sciences Institute of Geochemistry Chinese Academy of SciencesGuiyang 550081 China

Isotope fractionation during the evaporation of silicate melt and condensation of vapor has been widely used to explain various isotope signals observed in lunar soils, cosmic spherules, calcium-aluminum-rich inclusions, and bulk compositions of planetary materials. During evaporation and condensation, the equilibrium isotope fractionation factor(α) between high-temperature silicate melt and vapor is a fundamental parameter that can constrain the melt's isotopic compositions. However, equilibrium α is difficult to calibrate experimentally. Here we used Mg as an example and calculated equilibrium Mg isotope fractionation in mgsio_3 and Mg_2SiO_4 melt-vapor systems based on first-principles molecular dynamics and the hightemperature approximation of the B igeleisen-May er equation. We found that, at 2500 K, δ25 Mg values in the mgsio_3 and Mg_2SiO_4 melts were 0.141 ± 0.004 and 0.143 ± 0.003‰ more positive than in their respective vapors. The corresponding δ26 Mg values were0.270 ± 0.008 and 0.274 ± 0.006‰ more positive than in vapors, respectively. The general α-T equations describing the equilibrium Mg α in mgsio_3 and Mg_2SiO_4 melt-vapor systems were: α Mg(1)-Mg(g) = 1+(5.264×10~5)/T^2(1/m-1/m') and α Mg(1)-Mg(g)=1+(5.340×10~5)/T2(1/m-1/m'),respectively, where m is the mass of light isotope 24 Mg and m' is the mass of the heavier isotope, 25 Mg or 26 Mg. These results offer a necessary parameter for mechanistic understanding of Mg isotope fractionation during evaporation and condensation that commonly occurs during the early stages of planetary formation and evolution.

关键词：蒸汽系统同位素硅酸盐融化平衡计算 Mg2SiO4 mgsio3

Shock-produced akimotoite in the Suizhou L6 chondrite

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Science China Earth Sciences 2015年第6期58卷 876-880页

作者： CHEN Ming XIE XianDe State Key Laboratory of Isotope Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Key Laboratory of Mineralogy and Metallogeny Guangzhou Institute of Geochemistry Chinese Academy of Sciences

Shock-produced akimotoite was identified in the Suizhou chondritic meteorite, which occurs in two kinds of occurrence. The first is the irregular layers of akimotoite up to 4 ?m in thickness occurring in fractures and cracks of low-Ca pyroxene enclosed in the shock veins. The second is the zonal polycrystalline aggregates of akimotoite in shocked pyroxene grains close to the shock vein, where akimotoite occurs in a zonal area in between pyroxene and Mg Si O3-glass as irregular small clumps up to 5 ?m in size. This investigation suggests a solid-state transformation mechanism of pyroxene to akimotoite, and that akimotoite should have nucleated and grew in the area with abundant defects caused by shock deformation because the defect significantly enhances the solid-state reactivity and the kinetics of nucleation of high-pressure phase. The spatial relationship among the composed grains of pyroxene, akimotoite and Mg Si O3-glass(possibly vitrified perovskite) demonstrates a temperature gradient from the vein wall to the unmelted chondritic meteorite.

关键词：球粒陨石随州 mgsio3 带状区域玻璃化耳鼻喉科温度梯度缺陷区