聚碳酸酯經聚碳酸酯浸泡後20~120秒後,再將試片拿出來10~30秒讓表面沒有丙酮溶劑後，再將試片放入丙酮內，試片表面會形成二維空間的表面波紋，我們用快速傅利葉轉換後，可以得到表面波紋的週期。
我們討論試片沒有受到加馬射線照射、在真空中照射加馬射線和在空氣中照射加馬射線。在這些條件下我們改變溫度、時間、照射劑量和試片厚度。我們發現沒有照射加馬射線下的表面波紋的波長會隨著溫度和時間的增加，表面波紋的波長會越來越大。我們去比較空氣中照射試片和真空中照射的試片，我們發現在空氣中的波長會比在真空中的波長來的大，是因為有結晶的形成。我們用工研究光電所的表面粗操儀量測波紋的深度，我們發現當溫度、時間、照射劑量越大時，表面波紋的深度會越來越大，當到達最大值的時候波紋深度會變小，因為有結晶的產生。我們發現當試片厚度0.8mm的時候波紋間距會有最小值，波紋深度有最大值。

After swelling at the short times less than 300s, the specimen became two regions. One is the region where acetone did not diffuse in. The other is swollen by acetone. Take the specimen out till specimen without acetone, and then put the specimen into acetone again. We found that the beautiful pattern at the surface. This pattern has 2-D regular pattern. Surface patterns were analyzed by two-dimensional fast Fourier transform. Then, we can get macro wavelength of the pattern.
We studied three kinds of the specimen: non-irradiated specimen, irradiated in air and irradiated in vacuum. We changed parameters like temperature, time, dose and thickness of the specimen. We found that wavelengths of non-irradiated specimen and specimen irradiated in vacuum and in air were increased as immersion time and temperature increased. The wavelength of the specimen irradiated in air is longer than the specimen irradiated in vacuum because of the crystallites formed. We did some measurements of the amplitude of the pattern with time, temperature, dose and specimen thickness. The amplitude was increased as temperature, time, and dose increased but when the time and temperature were large enough, amplitude had a maximum value. We also did some experiments to find whether specimen thickness affects surface morphology. We found that wavelength had a minimum value, and amplitude had a maximum value when specimen thickness increased. We found that the crystallites were increased as time, temperature, oxygen and dose increased. Pattern wavelength and amplitude were affected by crystallization. When the specimen irradiated high dose in the air immersed in acetone, the crack and void were formed. We also found that when thickness of non-irradiated specimen is 0.4-0.6 mm, the crystallites can be formed and 0.8-1.2 mm specimen, no crystallite was observed. The specimens irradiated in vacuum and air also has a similar phenomenon with non-irradiated specimen, but we found some crystallites appear when the 0.4-0.8 mm specimen with 150 kGy irradiated in air.

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