本次研究工作主要在觀察磁性的形狀異向性，樣品主要分為內部磁矩沿長軸方向以及內部磁矩沿短軸方向，並且做多種不同厚度分析，厚度分為0.7、1.0、1.3、1.5、1.7(mm)五種不同厚度，材料皆使用聚-L-乳酸(PLLA)摻雜奈米微粒Fe3O4。大型鐵磁性物質內部由多個磁疇組成，每個磁疇壁大約10μm，所以我們使用的Fe3O4可以視作一個方向的磁矩，再利用我們自製的外加磁場儀器，再加熱的同時，使我們可以控制樣品內部的磁矩方向。
　　接著利用形狀異向性的特性，當內部磁矩方向平行長軸時，樣品受到的外加磁場會全數轉化為樣品產生的磁化強度，而內部磁矩垂直長軸時，會受到退磁場影響，而使磁化強度遠低於外加磁場強度。利用這項特性，我們就可以用超導量子干涉儀(SQUID)來觀察我們樣品是否符合形狀異向性。雖然研究中，在數據方面發現在1.0mm厚度下時，內部磁矩沿長軸方向的樣品有殘磁量突然升高的特殊現象，但是在與內部磁矩沿短軸方向的樣品做比較時，還是可以看出我們原先預期的數據，所以在這次研究中就不深入討論。此次研究主要目的在於，測試我們自製的方法是否能使樣品產生異向性，並利用此方法來製作生物醫療用微型機器人，值得慶幸的是，在此次研究中，我們最終確認了我們的樣品確實有受到磁化的影響，進而產生異向性特徵。
　　在文章中，我們也會提到如何製作儀器以及使用方法。主要是選用了較為方便的Arduino控制器，並自己撰寫程式碼，這也能使我們自製儀器的預算大幅降低，並且又可以完成我們的各項需求。

　　This research work mainly focuses on the shape anisotropy of magnetic. The sample is mainly divided into the internal magnetic moment extension axis direction and the internal magnetic moment along the short axis direction, and is analyzed by various thicknesses. The thickness is divided into 0.7, 1.0, 1.3, 1.5. 1.7 (mm) five different thicknesses, the material is doped with nano-particles Fe3O4 using poly-L-lactic acid (PLLA). The large ferromagnetic material is composed of multiple magnetic domains, each of which is about 10μm. Therefore, the Fe3O4 we use can be regarded as the magnetic moment in one direction. Then we can use our self-made external magnetic field instrument to reheat and make us The direction of the magnetic moment inside the sample can be controlled.
　　Then, using the characteristics of shape anisotropy, when the internal magnetic moment direction is parallel to the long axis, the applied magnetic field of the sample will be fully converted into the magnetization generated by the sample, and the internal magnetic moment will be affected by the demagnetizing field when it is perpendicular to the long axis. The magnetization is much lower than the applied magnetic field strength. Using this feature, we can use a superconducting quantum interferometer (SQUID) to observe whether our samples conform to shape anisotropy. Although in the study, when the data was found to be 1.0 mm thick, the sample with the internal magnetic moment extending the axial direction has a special phenomenon that the residual magnetic flux suddenly rises, but when compared with the sample with the internal magnetic moment along the short axis direction, It is still possible to see the data we originally expected, so we will not discuss it in depth in this study. The main purpose of this study is to test whether our homemade methods can make samples anisotropic and use this method to make biomedical micro-robots. Fortunately, in this study, we finally confirmed our The sample is indeed affected by magnetization, which in turn produces an anisotropic character.
　　In the article, we will also mention how to make the instrument and how to use it. The main reason is to use the more convenient Arduino controller and write the code yourself, which can greatly reduce the budget of our homemade instruments, and can complete our various needs.

第一章　緒論　1
第二章　理論基礎　3
　　　　2.1　物質磁性　3
　　　　2.1.1　磁性的來源-磁矩　3
　　　　2.1.2　物質的各項磁性特徵-順磁性、抗磁性、鐵磁性、反鐵磁性　4
　　　　2.2　磁性異向性　7
第三章　實驗方法　9
　　　　3.1　自製儀器介紹　9
　　　　3.1.1　掃描層積式外加磁場樣品機　10
　　　　3.1.2　環境磁場量測儀　15
　　　　3.2　超導量子干涉儀－SQUID　22
　　　　3.3　掃描式電子顯微鏡　24
　　　　3.4　實驗流程　26
第四章　數據分析　31
　　　　4.1　SQUID數據分析－M-T、M-H　31
　　　　4.1.1　ZFC、FC分析　31
　　　　4.1.2　M-H磁滯曲線分析　32
　　　　4.2　掃描式電子顯微鏡(SEM)、能量散色光譜儀(EDS)　41
第五章　總結　42
第六章　參考資料　44

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