【摘 要】
：
La0.8Ba0.2MnO3 nano-particles were synthesized by sol-gel process, and the crystal structure and morphology were characterized by XRD and SEM, respectively. The
【机 构】
：
School of Physics Science and Technology
【基金项目】
：
the Planned Item of Science and Technology of Hunan Province, China
论文部分内容阅读
La0.8Ba0.2MnO3 nano-particles were synthesized by sol-gel process, and the crystal structure and morphology were characterized by XRD and SEM, respectively. The complex permittivity and permeability were determined by microwave vector network analyzer in the frequency range of 2-18 GHz. The relationship between reflection coefficient and microwave frequency of La0.8Ba0.2 MnO3 was calculated based on measured data. The results show that the average diameter of La0.8Ba0.2MnO3 crystal powders is about 80 nm and the crystal structure is perovskite when being calcined at 800 ℃ for 2 h. The microwave absorbing peak is 13 dB at 6.7 GHz and the effective absorbing bandwidth above 10 dB reaches 1.8 GHz for the sample with the thickness of 2.6 mm. The microwave absorption can be attributed to both the dielectric loss and the magnetic loss from the loss tangents of the sample, but the former is greater than the latter.
其他文献
为保护、挖掘和开发马家沟芹菜这一地方名牌,2003年春,“马家沟芹菜品种资源保护及标准化技术研发”项目经青岛市科技局立项,由平度市农业局和李园街道办事处在东马家沟芹菜
真题回放没有太阳的地方,昏暗一片;没有太阳的时候,凄冷酷寒。太阳升起,光明无限;太阳升起,生机盎然。请以“升起心中的太阳”为题目,写一篇不少于600字的作文。试题解读2011
那天带你去看《海洋》,电影里有只海狮,在一片脏兮兮的海域穿梭游弋,彷徨而好奇地注视着身边的垃圾和超市里的手推车,我不禁难过起来。我想起了家乡的那片海。曾经,那里天蓝
教学有法,但无定法。“无定法”是说数学教学没有永恒的一成不变的教学方法,即使人们公认的某种行之有效的教学方法,教师在实践中必须因校因人(指教师)、因时、因学生、因教
工程建设项目由于施工涉及面广,项目位置不固定、生产流动、结构类型不一、质量要求不一、施工方法不一、建设周期长、受自然条件影响大等特点,因此,施工项目的质量比一般工
随着我国社会经济的快速发展,对于煤炭能源的需求量不断增多,而采矿技术的应用则是决定生产效率与安全性的主要因素。近年来,国内各主要煤炭产区的能源储量明显减少,而新型清
In China,qanats (kanerjing/karez) exist only in Xinjiang Uygur autonomous region,being one form of traditional irrigation technology that made great contributio
无公害花生病虫害防治应优先采用农业防治和生物防治,可以使用高效、低毒、低残留的除草剂进行化学除草,按国家规定严禁使用高毒、高残留、高生物富集性、高三致(致癌、致畸
水环境监测工作是水文工作重要的一环,是水资源保护、水生态管理的依据。本文通过对保山市水环境监测工作发展现状及存在问题的思考,提出在经济社会高速发展的今天,水环境监测工作健康、有序发展的合理建议。