全國中小學科展

2013年

變形泡膜-傾角對柱體面轉變影響與椎體面膜探討

本研究主要探討傾角對面轉變的影響與面轉變的原因。當柱體由肥皂水中拉起時,泡膜圖形可分為中央膜平行與垂直底面的形式,兩種形式因高的變化而互相轉換的過程稱為面轉變。三到六角柱傾角越大,面轉變時的高越大,反之亦然;六角柱可以面轉變,且在40°到45°之間有臨界角度存在。本研究以力與能量的角度解釋面轉變.泡膜藉由改變面積以達到最低的能量、維持穩定狀態,因此本研究計算、比較不同形式的泡膜面積,以解釋面轉變。我們同時發現三角錐與四角錐都不會發生面轉換;三角錐的實驗值多大於理論值,四角錐的實驗值則多小於理論值。

棋盤中矩形周長和最小的分割策略

題目緣由是數學奧林匹亞預選題的其中一題組合問題,題目探討在2^m×2^m的棋盤中(m∈N)先分割出對角線上的2^m一單位正方形,之後將剩下兩塊狀似等腰直角三角形的棋盤分割為若干個不重疊的矩形,求此棋盤被分割出的所有矩形周長和最小值。本文將原命題推廣至nn×n棋盤與m×n棋盤的情況,在2^m×2^m中達到周長最小值的矩形分割方式十分直觀,但證明過程中直接構造函數2x〖log〗_2 x以及利用琴生不等式等方法不甚直觀,於是我們在n×n部分的最後給出了另解,並說明原題為其特殊情況。 n×n的部分沿用原題之方法定義了十字分割,我們證明了利用完全十字分割可達到最小值,為4n(m+3)-2^(m+3) (其中2^m≤n

好「鉀」的溶液-鉀離子濃度的偵測

Utilization of Starch for production of plastic-like material

The research is based on the production of biodegradable plastic-like material by only using household materials. Also, it can be made at home and it causes no harm to the environment. The biodegradable plastic-like materials made by different ratio of amylose, amylopectin, glycerol and water has different use. The finished product has smooth surface, highly transparency and well flexibility. Also, it can support strong load and be able to be deformed under stress. Ratios of components are tested on: 1. Easy to injection mold 2. Flexibility 3. Tensile strength and ductility & 4. Water resistance. It is found that the ratio of tapioca starch: glycerol: water = 1.5: 0.5: 9 can withstand 13N of force and 1.5: 0.93: 9 with high ductility. To improve water resistance, more amylopectin should be added to amylose. The best water resistance ratio is glutinous rice flour: tapioca starch: glycerol: water = 0.6:0.91:0.5:9 can withstand 16N force, while 0.6:0.91: 0.93:9 and 1.35:0.16: 0.5:9 with high ductility. All materials are available in supermarkets. Higher ratio of tapioca starch can produce bookmark, with laminate effect. More tough, higher ratio of glutinous rice flour can make cups, spoons and dishes.

雙橢圓交點軌跡之研究

(PA)+(PC) =t為以A、C為焦點的橢圓,滿足(PA) +(PC)=(PB)+(PD) =t的P點軌跡可視為以A、C及B、D為焦點且長軸等長的橢圓在長軸變化過程中的交點軌跡,稱該曲線為EIC(AC,BD)。本研究主要討論四邊形ABCD為鳶形時,EIC(AC,BD)的代數方程式、曲線變化情形及其是否平滑。我們可將EIC曲線分為三類: 1.兩條非封閉曲線 2.一條非封閉曲線及一條封閉曲線 3.一條封閉曲線。由兩條曲線變為一條曲線的臨界條件為(BA) ̅=(BC) +(BD),此時圖形為一條非封閉曲線及一點(B點),此時EIC(AC,BD)曲線族的包絡線為以B、D為焦點、長軸長為(AC) ̅的橢圓。另外,從代數方程式得知除了原點為奇異點,EIC曲線為平滑曲線。從圖形可發現EIC曲線與雙曲線、橢圓曲線(Elliptic Curve)、蚌線(Conchoid of de Sluze)極為相似,而其實質關聯性則有待未來研究。

Carbon Nanostructures Via Dry Fce Exposed to High Temperature

This science project is designed to answer a question of whether or not a chemical reaction is needed to produce industrial quantities of carbon nanostructures by exposing dry ice to a high temperature that is at least 3100°C. A small carbon arc furnace powered by an electric welder is used to produce the high temperature. During control runs, the carbon arc furnace is energized for a predetermined time, after which the carbon arc furnace is de-energized and any carbon particles within the furnace are collected. During carbon nanostructures synthesis runs, dry ice is placed within the carbon arc furnace. The carbon arc furnace is energized and the dry ice is consumed for the predetermined time. Carbon nanostructures synthesized during the synthesis runs are collected once the carbon arc furnace is de-energized and allowed to cool. The volume of the carbon particles collected during the control runs is compared to the volume of the carbon nanostructures produced by the synthesis runs. This science project has discovered that on average at least 16 times more carbon nanostructures are produced during synthesis runs consuming dry ice as opposed to the control runs. Moreover, the synthesis runs did not rely on chemical reactions. Further still, samples of the synthesized carbon nanostructures were imaged using a transmission electron microscope (TEM). The TEM images clearly show high-quality carbon nanostructures that include carbon nanotubes, faceted carbon nanospheres, and the super-material graphene.

綠茶多酚EGCG對小腦萎縮抗氧化保護之探究

小腦萎縮症第三型SCA3為體染色體顯性遺傳疾病。已知為CAG三核甘酸重複序列數目過多的動態突變,造成polyQ在腦部神經細胞核內形成包含體,這種蛋白在細胞內長期堆積會導致細胞退化並死亡。此外,在SCA3熱休克蛋白的表現量較低,使蛋白不正常聚集造成細胞大量釋放氧化性刺激,促使細胞走向凋亡。根據先前研究發現低劑量綠茶多酚EGCG (epigallocatechin-3-gallate) 具有抗氧化且選擇性保護神經細胞的功能,避免氧化壓力導致細胞凋亡。此研究以SCA3患者與正常人的淋巴母細胞株來研究,給予EGCG保護來觀察EGCG在患者與正常人的細胞內對H2O2氧化壓力的耐受性差異,進一步探討EGCG對SCA3熱休克蛋白的表現量,同時觀察EGCG是否影響抗凋亡蛋白的表現。

在地表上畫畫-球面上的尺規作圖

在這分作品中我們在球面上尺規作圖。目的是要完整描述球面上可作的角度。我們從平面尺規作圖的知識出發,卻遇到了困難,像是有很多平面尺規作圖的方式不能被如法炮製地運用到球面上。為了達成目標,我們著手探討在球面上和平面上作圖方式的關係,方法如下:先定義兩個重要名詞S :球面上能作角度(弧長)的集合和P:平面上能作角度(弧長)的集合。透過向量方程式的證明我們得到S⊆P。利用我們從球面三角學公式衍生出的作圖方法,並藉由「體」證明出P⊆S。在P=S 的基礎上,我們引用伽羅瓦理論的已知結果,終於得到結論,也就是「球面上一個角度可作若且唯若其餘弦值為1經過有限次的加減乘除與開平方根運算」。最後我們也給出了球面上正4邊形、正5邊形和正17邊形的作法。

勻稱分割

本研究主要透過不同的向度與規則,延續之前的研究。我們證明了頂點組態僅含有單一種秩數的 勻稱分割共有5種;頂點組態中含有兩種不同秩數的 勻稱分割,其 的最大值為5,共有13種;頂點組態中含有三種不同秩數的 勻稱分割,其 的最大值為4,共有3種;而頂點組態中含有 種不同的秩數的 勻稱分割在 時無解;最後,我們透過GSP軟體將所有解的圖形繪製出。

探討CID384634合併臨床賀爾蒙治療用藥tamoxifen對三陰性乳癌的作用機轉

乳癌是台灣女性死因第四名,其中的三陰性乳癌因具備高轉移力,又缺乏特定受體而不適用於標靶藥物治療或賀爾蒙治療法,所以其治療方法有其困難度。CID384634為2-phenynaphthyridone(2-PN)的衍生物,此藥物可藉由干擾微管蛋白聚合抑制致瘤性高的細胞株生長,於是我們想探討CID384634對於高度轉移性的三陰性乳癌是否也有同樣的治療效果。本研究以MTT assay和西方墨點法探討其治療效果與作用途徑,並發現CID384634可藉由回復雌激素受體表現,並且在合併臨床賀爾蒙治療用藥tamoxifen有明顯抑制三陰性乳癌細胞存活率。實驗也證實CID384634具有抑制上皮細胞及間質細胞轉換的作用。我們希望在不久的將來CID384634可以用來治療三陰性乳癌。