Considering Fukushima’s contaminated water treatment system using algae ~ To protect the oceans from radioactive emissions
Nine years ago, the Great East 日本 Earthquake caused the spread of a large amount of radioactive materials. Even now, the amount of contaminated water is increasing at a rate of 180 tons per day, and it is said that the storage tanks for the contaminated water will run out of space in the next two years (Fig. 1). If the contaminated water is discharged into the ocean, it will cause reputational damage to the fishing industry, and the environmental pollution. We are conducting to research to prevent it from happening. In the wake of the nuclear accident, the senior started water quality surveys at Chaya Marsh near the school. During the survey, they found (Chara braunii, Fig. 2), (Nitella axilliformis, Fig. 3), Closterium moniliferum (Fig. 4), and (Nostoc commune, Fig. 5).
Dependence of Alloy Composition in Color Change of Brass Foil by Oxide Thin Layer Formation
It is known that copper foil undergoes a color change in heating by oxide thin layer formation. Therefore, we focused on the color change by the oxidation of brass foil. Brass foil (Akaguchi (Cu87%Zn13% alloy) and Aoguchi (Cu85%Zn15% alloy)) also undergoes color change by oxidation, and it shows heating time and temperature dependence. Brass foil need longer heating time to appear color change than copper foil, and we can visually confirm that the brass has corrosion resistant. In addition, color change of brass foil depends on the percentage of copper in the brass, and Aoguchi shows rapidly color change in same heating condition. We show that brass has different physical properties than copper, even with a high percentage of copper in brass, and this was verified through comparison using diffusion length and RGB data in Aoguchi and Akaguchi. We demonstrate these colored brass foils are used as art materials, and our results expanded material using possibility of brass foil.
Σn=1∞(n/(Cn2n))=√(x/(4-x)3) (√x(4-x) + 4sin-1(√x/2))與其相關的無窮級數
本文從一個博奕遊戲談起,探討遊戲的期望值得到一無窮級數Σn=1∞n/Cn2n 並嘗試用相關的數學概念與方法思考,首先處理問題Σn=1∞n/Cn2n 與Σn=1∞n2/Cn2n 的值,過程中利用了Σn=1∞n/Cn2n 函數與Σn=1∞n2/Cn2n 函數的性質將欲求之無窮級數轉化成積分或微分方程式的型態,再利用奧斯特洛格拉德斯基積分方法解出所求。 為了更有效率的得到相關之無窮級數,引進了微積分工具中之冪級數的概念,輔以微分方程式公式解求出了 f(x)=Σn=1∞Xn/Cn2n =√x/(4-x)3 (√x(4-x) + 4sin-1(√x/2)), x∈(-4,4), 進而推廣、延伸與其相關的一系列無窮級數,並利用導函數f'(x)求得 Σn=1∞n·2n-1/Cn2n的值。 接下來討論與f'(x)相關的無窮級數,發現可利用f(x)的高階導函數透過迭代方式得到Σn=1∞nm/Cn2n的值,其中m為任意正整數,歸納這些級數後可以應用在本文之博奕遊戲,讓獎金的選擇更富有變化性。 最後觀察f(x)與卡塔蘭數列{Cn}的倒數所構成之冪級數有所關聯,解出 Σn=1∞Xn/Cn的收斂函數後求出了Σn=1∞1/Cn的值以及{1/Cn}的偶數項與奇數項的和。
魔環
假設G為簡單圖,令V(G)、E(G)分別為G的頂點與邊所形成的集合,|V(G)|與|E(G)|分別代表G的頂點集合與邊集合的元素個數。若u, v∈V(G)且u, v有邊相連,則將此邊記為uv∈E(G)。對於給定的填單圖G,若存在函數f: V(G)∪E(G)→{1, 2, 3,…, m},其中m=|V(G)|+|E(G)|且函數f滿足下列兩個條件: (1)f為1-1且映成函數: (2)對於每個邊uv∈E(G),f(u)+f(v)+f(uv)恆為定值T, 則稱函數f為圖G的一個『魔函數』,G為一個具有『魔和』為T的『魔圖』。 在此次研究中,我們證明了下列的結果: 1.任意圈Cn為具有魔和[(5n+4)/2]或[(7n+3)/2]的魔圖; 2.長度為奇數n的圈Cn,其中n≠5,為具有魔和(5n+5)/2的魔圖; 3.長度為n=4t+2(t≧1)的偶圈Cn,為具有魔和(5n+6)/2的魔圖; 4.長度為奇數n的圈Cn外加兩個相鄰的懸掛邊所成為的圖為一個魔圖; 5.三個具有共同端點的n-路徑所形成的圖為一個魔圖。