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摘要近年来被控温系统与设备散热功率密度以及热负荷迅速增加、内外流变化逐渐加剧，并且控温精度逐渐提高，热辐射特性没有自动调节控制能力，不能够根据系统和设备的发热量而变化。自身的热辐射特性由外部热流变化调节，不能够满足系统自身的温度控制要求。基于热致变色原理的热辐射表面能够根据系统设备的温度水平和内外热流变化，从而调节自身的辐射特性，从而能够实现系统设备温度的主动控制。因此开展基于热致变色原理的表面辐射特性转变机制与控制方法的研究具有非常重要的应用价值和现实意义。本文以钙钛矿型锰氧化物La0.8Sr0.2MnO3为基础材料并且掺杂氧化钕粉末制作基于热致变色原理的热辐射表面，研究其热辐射特性，探索其辐射特性的控制方法以及对提高系统与设备的热控技术水平有着非常重大的科学意义。本论文主要的研究内容包含以下几个方面：27225
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（1）Nd掺杂热致变色材料的制备和表征
本论文以La(NO3)3•6H2O、Mn(NO3)2•4H2O以及Sr(NO3)2为原料，拟采用溶胶-凝胶法制备La0.8Sr0.2MnO3粉末，再按5%，15%,25%比例分别掺入氧化钕粉末，经过1350℃焙烧，压块成型。
（2）基于热致变色原理的表面热辐射特性研究
本论文将Nd掺杂热致变色材料作为研究对象，用傅立叶红外光谱仪测量此材料的反射率光谱，采用反射计光学方法来间接测量材料的红外发射率。分析掺杂Nd元素对基于热致变色原理的表面热辐射特性的影响，从而能够揭示发射率的可调特性。
关键词 Nd-掺杂， 热致变色， 可变发射率
毕业论文设计说明书外文摘要
Title Preparation of Nd-doped thermochromic material and its Variable Emissivity properties
Abstract
With the power density of heat dissipation and the heat load in a system increasing, there is a growing demand for a better performance of thermal radiative surface because these with constant emissivity cannot meet the demand any more. For example, thermal radiative surface, such as ZnO coating and OSR reflector, are usually used to dissipate heat from the satellite surface. However，these traditional thermal radiative surface have a constant emissivity, they do not adjust their thermal radiative properties alone in response to the violent fluctuation of exterior heat flux. Therefore, there is a serious need for developing novel thermal radiative surface with its radiavite properties automatically adjusting in response to the temperature variation. Perovskite type manganese oxides Nd-doped La0.8Sr0.2MnO3 were selected as a basic material to prepare a novel thermal radiative surface, and investigation on thermal radiative properties of surface and its control method based on thermochromic phenomenon was performed. The contents of this paper mainly include the following parts.
（1）Preparation of Nd-doped thermochromic function material
Solid stated reaction is used to prepare the bulk thermochromic functional material. Nd is doped in the thermochromic functional material by 5%，15%，25%.
（2） Thermal radiative properties of thermochromic functional material
Reflectivity spectra of Nd-doped thermochromic device or coating are measured using the FT-IR spectrometer .The emissivity and solar absorptivity are deduced from the experimental reflectivity data.
Keywords Nd-doped, Thermochromic device, Solar absorptivity
目 次
1 绪论 1
1.1 研究背景 1
1.2 国内外研究现状 1
1.3 问题与不足 2
1.4. 本课题的主要任务 3
1.5本文的工作简介 3
2 钕掺杂热致变色功能材料制备与表征 5
2.1 概述 5