RUI: Carbon Encapsulated Magnetic Particles

RUI：碳封装磁性粒子

• 批准号: 9405941
• 负责人: Kiumars Parvin
• 金额: $ 28.43万
• 依托单位: San Jose State University Foundation
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1994
• 资助国家: 美国
• 起止时间: 1994-08-01 至 1998-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9405941&HistoricalAwards=false
• 关键词: RUI; Carbon; Encapsulated; Magnetic; Particles

9405941 Parvin This research emphasizes synthesis purification, magnetic extraction, and structural and magnetic characterization of carbon- encapsulated materials. The carbon-encapsulated particles of magnetic alloys (iron-transition metal alloys, cobalt-transition metal alloys, nickel-transition metal alloys, and iron-rich rare earth alloy R2Fe17, where R is a rare earth element) are synthesized in a standard fullerene arc chamber. An efficient method extracts the magnetic particles from nonmagnetic species using interaction of magnetic moments with a magnetic field gradient. Characterization includes particle size distribution analysis using scanning electron microscopy (SEM), compositional and structural characterization using transmission electron microscopy (TEM), and x-ray diffraction analysis (XRD). The magnetic nature of the materials is studied using direct measurements of the magnetic moment of the particles over a wide range of temperature and magnetic field. Additional information concerning the magnetic nature of the iron-containing samples is determined in a series of Mossbauer spectroscopy measurements. This grant is a collaborative research project involving San Jose State University, SRI International, and E.I. duPont de Nemours. SRI international is the site for synthesis, purification, and magnetic extraction of the materials and XRD studies. SEM and TEM work is done at DuPont, and magnetometry and Mossbauer spectroscopy is carried out at San Jose State University. %%% Such materials are of interest because they combine corrosion protection from the closed carbon polyhedra and desirable ferromagnetic properties that can be tailored by the choice of particles to be encapsulated and the processing conditions. ***

小行星9405941 本研究着重于碳包覆材料的合成、纯化、磁性萃取、结构与磁性表征. 磁性合金（铁-过渡金属合金、钴-过渡金属合金、镍-过渡金属合金和富铁稀土合金R2 Fe 17，其中R是稀土元素）的碳包封颗粒在标准富勒烯电弧室中合成。 一种有效的方法利用磁矩与磁场梯度的相互作用从非磁性物质中提取磁性颗粒。 表征包括使用扫描电子显微镜（SEM）的粒度分布分析、使用透射电子显微镜（TEM）的组成和结构表征以及X射线衍射分析（XRD）。 使用在宽的温度和磁场范围内的颗粒的磁矩的直接测量的材料的磁性性质进行了研究。 关于含铁样品的磁性的其他信息是在一系列穆斯堡尔谱测量中确定的。这项资助是一个合作研究项目，涉及圣何塞州立大学，SRI国际，和E. I。杜邦公司。SRI国际是合成，纯化和磁性提取材料和XRD研究的网站。 SEM和TEM工作在杜邦公司完成，磁力测量和穆斯堡尔谱在圣何塞州立大学进行。 这种材料是令人感兴趣的，因为它们联合收割机了对封闭碳多面体的腐蚀保护和期望的铁磁性能，所述铁磁性能可以通过选择待封装的颗粒和加工条件来定制。 ***