由於磁性流體薄膜結構在外加垂直磁場下，會受到磁場強度及磁增率高低之影響，因而產生不同的結構變化。故為了更加了解磁場及磁增率與結構之間的關係，我們改變磁場在起始磁場下的條件，以產生不同的初始結構。然後探討磁性流體薄膜在不同的初始結構下，當磁場繼續增加時，結構隨磁場增加時之演化，以釐清磁性流體初始結構對結構隨磁場增加時之演化的影響。在此藉著改變起始磁場強度大小、磁場在起始磁場下的停留時間長短以及提高磁增率三種方式，改變初始結構。
首先我們觀察磁場由零增加時，磁性流體薄膜隨著外加磁場增加時之瞬時結構變化。並將磁場由零增加到某一磁場強度下，停留3分鐘以待結構平衡穩定後，再將磁場由此強度開始增加，同時記錄磁場增加過程中磁性流體薄膜之瞬時結構。根據在不同的起始磁場下，磁性流體薄膜結構隨磁場增加過程的演化，歸納出磁性流體薄膜於動態垂直磁場作用時之結構相圖。進一步藉由此相圖，釐清磁性流體薄膜在外加垂直磁場下之結構行為所蘊含的物理機制。
繼而探討在固定磁場下，磁性流體薄膜隨時間演化過程，以了解結構隨時間增加之變化。並紀錄磁場在起始磁場下停留不同時間後，磁場開始增加時，磁流體結構隨磁場增加之演化。根據磁場在起始磁場下停留不同時間後之結構演變，歸納出磁流體薄膜之結構相圖。進一步比較停留時間對初始結構的影響，以釐清時間和磁性流體薄膜結構隨磁場演化時之關係。
最後我們探討在高磁增率中結構隨時間增加時之變化。並紀錄磁場在起始磁場下停留不同時間後，磁場開始增加時，磁流體結構隨磁場增加之演化以歸納出結構相圖。進而研討在不同的磁增率下，磁性流體薄膜結構相圖上的差異，以釐清磁性流體薄膜結構隨磁場增加時，磁增率與其結構演化之關係。

According the previous studies, it has been shown that the static structures of magnetic fluid thin films under vertical applied magnetic fields are influenced by the magnetic field strength H and the sweep rate dH/dt. In order to understand the correlation between these parameters and the dynamic structures of the films, we modulate the initial structure of the film by means of changing the initial magnetic field Hi, the duration time td under Hi, and the sweep rate of the initial magnetic field dH/dt. With the controlled initial states, the evolution of the structures under sweeping magnetic fields is investigated in detail.
First of all, the dynamic structure of the magnetic thin film was recorded immediately after the magnetic field began increasing from zero. Then the structural evolution with a certain initial magnetic field Hi was studied. As the magnetic field reached Hi, the field was held for 3 minutes to stabilized the structure of the film. Subsequently, the applied magnetic field was further increased with the same sweep rate and the structure of the film was observed simultaneously. A series of these processes with various Hi was studied and the structural evolution was summarized in the H-Hi structural phase diagram. The implications of the structural phase diagram were discussed to clarify the physical mechanism of the magnetic fluid thin films in the dynamic processes.
Secondly, the evolution of the structure at various duration time td under Hi was analyzed. The structure of the film was investigated right after the Hi was held as well as in the followed sweeping magnetic field. When many of these processes were recorded, the H-Hi structural phase diagrams with different td were constructed. The influence of td on the structural variation of the magnetic fluid thin films was discussed.
Finally, we probe the structural variation of the magnetic fluid thin films in higher sweeping rates of the magnetic field. The structural evolution with different duration time td at a higher sweeping rate was also recorded and analyzed. As above, the H-Hi structural phase diagram was constructed for various sweeping rates to conclude the observed dynamic structures. The influence of the sweeping rate dH/dt on the structural evolution of the magnetic field thin films was discussed according to the phenomenon summarized in the structural phase diagram.

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