全國中小學科展

一等獎

水滴在高溫鋸齒狀金屬表面上的爬坡現象

實驗發現,在高溫並排鋸條之齒面上可以形成懸浮水珠,而水珠具有爬坡的現象。當鋸條齒面溫度達四百度且鋸條傾斜角低於二十度時,水滴均可向上爬坡,特別的是,角度在十二度內,大小水滴的爬升速度皆有隨著角度提高而變快的趨勢,且質量較小的水珠爬升速率較快。 水珠之所以能向上爬坡與其表面受熱快速蒸發和齒廓曲線有關。首先,水珠因受熱在周圍形成一層很薄的蒸氣層,阻隔熱的傳遞,使得在鋸齒面上可以形成懸浮水珠,持續一段時間而不會立即蒸發;而水珠爬坡的現象,肇因於蒸氣壓力和蒸發所產生的反向動量,配合不對稱的齒廓曲線,造成水珠會受到一個沿斜坡向上之淨力,進而可以爬坡。綜合前述的原因,我們可以合理的解釋各項實驗結果。

解開神秘果的奧秘-檸檬變柳丁的原因

原產於西非的「神秘果」,嘗了之後,30~200 分內,所有酸苦的東西嘗起來都是甜的。在深入蒐集相關資料後,我們發現神秘果有多種特殊效果,僅擷取以下幾種感興趣之方向來研究。〈1〉使酸苦的感覺變甜〈2〉解酒〈3〉消除蚊蟲叮咬之腫、癢〈4〉抗氧化能力極強。用食鹽水可萃取出miraculin 這種醣蛋白,經由生化實驗,推測使酸味變甜為其cover 舌尖甜味味蕾之結果,分子量約為40000 左右;但在檢測過程中,發現對咖啡、黃連和肉桂,都沒有太顯著的效果,只有酸味有顯著的改變,和以往所閱讀的研究報告有出入,因此懷 疑有氧化還原等其他化學效果,將再做深一層研究。消除蚊蟲叮咬之腫癢的成分確定為小分子所致。經由Prolox 當量測定法檢測神秘果抗氧化能力數值高達4974g/nmol,比一般中草藥及蔬菜多3000 左右。使酸變甜的原因若深入研究對糖尿病患者和減肥者都是一大福音,塗抹蚊蟲叮咬藥膏也可用天然物質製作,而抗氧化能力高更對人體健康有所幫助。當台灣已大量栽植,相對於日本及美國因地寒而無法培育成功,神秘果研究可成為另一項產業發展契機。 "Miracle fruit” is a fruit from West Africa. Though it's not sweet itself, if you eat anything that is sour or bitter after eating miracle fruit, the taste will turn sweet. After researching further material, we discovered that there are many amazing functions in miracle fruit, and decided to pick up some of which to study. (1) Turning the sour and bitter tastes into sweetness (2) Relieving alcohol (3) Relieving the hurt from mosquitoes and bugs (4) An excellent antioxidant. We can extract the miraculin that changes the taste from NaCl (aq), and through the biological experiment, we guess that's because miraculin covers the sweet sensor. The molecular weight of miraculin is about 40000.According to the experiment, we found out that miraculin doesn't have a great effect on the taste other than sourness, such as the bitterness of black coffee, Coptis chinensis, and cinnamon. . It is much more different from the former report we read. So we doubt that there are some other reactions. The thing, which relieves the hurt from mosquitoes and bugs, are sure to be a simple molecule, not a protein. By the Prolox equivalent weight experiment, we found that the ability of antioxidation got to 4974g/nmol, which is much higher than the normal vegetables and fruits. The effect of taste changing is really good news for diabetics and weight reducers. And the medicine can also be made by natural material. The excellent antioxidation is helpful for our health, too. Since Japan and America cannot grow the miracle fruit because of the cold weather, developing the functions of miracle fruit seems to be another chance for Taiwan to stand out in the world.

植物葉片自動辨識系統

在我們週遭環境中常可見到許多種類的植物,然而可以叫出名字的卻少之又少,或許我們可以查閱植物百之類的書籍,但是這類書籍通常多不在手邊,就算有了植物百科,也不易翻到顯示該種植物的正確章節。假如我們可以將想要認識的植物葉片影像取得後,透過網路將該影像傳送至植物葉片資料庫查詢,經過電腦的自動分析辨識後,再將結果傳送回來,這樣不是比查閱植物百科方便多了嗎?本研究提出一種利用輸入葉片的影像來進行植物資料庫辨識查詢的方法,藉著兩階段處理的策略及最佳權重組合式的特徵值來調校系統,以達到較佳的整體辨識效能,從實驗測試的結果得知,我們的策略與方法確實有效,有82%的查詢葉片可以被精確的辨識出來,而每次查詢的平均反應時間只要17.22 秒。In our living environment, there are many kinds of plants, but we can only name a few. We may consult an encyclopedia about plants, we always can’t find any encyclopedia with us. Besides, even if we have one, it won’t be easy to find out the proper section or the exact page immediately. How should we solve this problem? One significant improvement can be expected if the plant recognition can be carried out by a computer. First, we take a picture of the unknown plant’s leaf. Then, we transmit this image into a leaf database to recognize. After the recognition we will get the answer easily. By using a computer-aided leaf recognition system, non-professionals can also identify many plant species. Isn’t it much more convenient than checking the encyclopedia? In this study, we present an efficient method for leaf database retrieval by inputting leaf images. We use a two-stage approach and combined features with optimized weight to adjust the system to get the best system performance. The result of the experiment shows that our approach is workable and efficient. 82% leaves of the query images can be recognized accurately. And in general, the average response time only takes 17.22 sec per query.

Emitting Gold Nanodots Synthesized via Protein Templates

本研究利用蛋白質的環保、生物活性,金奈米粒子的低毒性,及蛋白質金奈米粒子的螢光特性,合成可應用於生物體內之螢光蛋白質金奈米粒子,從而利於標靶藥物研究。本研究選擇與眾多疾病相關的胰島素,以最佳方式合成紅色螢光胰島素金奈米粒子,有助於探討糖尿病相關機制。並嘗試以養晶得到結晶狀的胰島素金奈米粒子;經由離子測試發現胰島素金奈米粒子十分穩定,更可應用於細胞內微量氰離子檢測;根據CD光譜,確認胰島素金奈米粒子與胰島素的蛋白質二級結構相似。之後利用MTT測試細胞毒性,並將胰島素金奈米粒子餵入細胞,並取得細胞螢光影像,證明胰島素金奈米粒子可經由細胞表面之胰島素受體進入細胞內,且呈現紅色螢光,證明胰島素金奈米粒子可用於生物體內顯影追蹤。利用老鼠實驗證明胰島素金奈米粒子具有胰島素降血糖之功用。

解開蔗糖水解的秘密

本研究利用偏振片、量角器為刻度盤、雷射光為光源,及照度計為偵測器,組裝一個簡易且可靠的旋光度計。我們利用單位時間旋光度的變化量當作反應速率,來測量蔗糖的水解速率,同時求出蔗糖水解反應的反應級數、速率常數(k)。利用糖類的旋光度具有加成性之特性,找出不同混合比例時的旋光度,追蹤實際蔗糖水解的每個狀態,找出最後平衡狀態,同時將蔗糖水解平衡結果顯示,旋光度與濃度有線性關係,而蔗糖水解反應對蔗糖而言為一級反應。接著,我們在蔗糖水溶液中加入不同種類的酸,探討催化劑的種類與蔗糖水解反應速率的關係。 In this research, in order to measure the optical rotation accurately without expensive equipments or complex process, we assembled a polarimeter by ourselves. With simple materials which can be found in ordinary senior high school laboratories, including a calibrated scale, a simple Luxmeter, a laser as the photo source, and other side devices. The Polarimeter ended up operating fluently and accurately. We put the laser under a tube, which has two pieces of polar screens on the top of it and on the bottom of it, ,and put a luxmeter just above the tube. When we slowly rotate the polar screen on the top, the figure shown on the luxmeter changes. By numerical analysis, we can get information about the hydrolysis of polarized substance. Secondary, we measured the optical rotation of glucose, fructose, malt sugar, galactose, and sucrose to get their specific rotation. Then we measured the optical rotation of sucrose every five minutes. By doing this, we could keep track of the hydrolysis rate of sucrose, figure out the order of reaction, and the rate constant (k) and the equilibrium constant (K). Thirdly, we used different kinds of acids into sucrose solution as the catalyst, and observed the effect. The result showed that hydrochloric acid is a better catalyst to this reaction than sulfuric acid and nitric acid. The polarimeter of this research can be used in science education of junior and senior high school. By teaching students to assemble and operate the self-made polarimeter, students can know better about optical rotation and polarized substance. Also, the interest in this experiement will add to students’ motivation to do science research.

透水式攔砂壩的設計準則

由於台灣山區溪流短小陡急,土石流災害嚴重,透過式防砂壩攔阻工法為現\r 今之趨勢,而帄面透水柵具有一般透過式壩的優點,不但能將土石流轉化為水砂\r 流,還可以減低土石流衝擊力造成的損壞及改善上游儲砂空間不足的問題。本研\r 究採用改良式帄面柵,在下游處增設分流河道,可改善分離出之細顆粒土砂水與\r 大礫石再度結合之危險。此工法於2003 年引進台灣後,尚未廣泛應用,主要原因\r 為缺乏設計之經驗式,因此本研究針對透水柵的柵棒長度(L/ Dmax)、棒淨間距\r (b/ Dmax)、柵面架設方式、柵面篩分角度(θ)等多項重要因子進行室內渠槽\r 試驗,最後提出土砂篩分比與攔阻率的趨勢方程式,設計時以總攔阻率(R)高為\r 原則,輔以篩分比(S)與貯砂率(R1)高,即可有良好之成效,期望能作為國內\r 外現場工程施做時之參考,結果如下所示。

簡易方法測量擴散係數

溶液和水置於同一容器中,當溶液中的溶質向上擴散時,溶液的濃度會隨著\r 高度改變,形成濃度梯度以及折射率梯度dy/dn。\r 寬度a 的透明方形盒,下方盛溶液,上方加入水,雷射光照射和鉛直成45°\r 的玻璃棒,再照射方形盒時,由於溶液的折射率梯度,雷射光在屏上形成鐘形曲\r 線,向下偏Z 的距離,r 為容器至?的距離,ar/Z=dy/dn 。\r 兩液原始交界處(y=0)鐘形曲線最低位置(Z)隨著時間(t)改變,測量Z 及t 作1/Z平方-t圖,由其斜率可算出擴散係數D。\r 濃度較高的二元混合液,例如甘油水溶液,當其重量百分率濃度未超過70%\r 時,擴散係數仍不隨濃度改變;但在屏上所形成的鐘形曲線,其最大偏折點不但\r 逐漸上升,還向甘油方偏移。測量偏移點所對應的液高(y),以及經歷時間(t);\r y平方= 2Dt,作y-√?? 圖,由其斜率亦可算出甘油的擴散係數。

地球真的發燒了嗎?─深入探討全球暖化的趨勢

在上了基礎地球科學之後,我們更加關心所處的環境。我們想要了解地球暖化的趨勢是如何?各緯度地區的暖化程度有著怎樣的差異?我們至各國網站搜尋氣象站的原始資料,並利用Microsoft Excel作數據分析。我們比較了不同緯度區域的升溫現象,並找出各測站數十年來暖化程度隨時間的變化。結論與我們以前所認知的事實-地球正在迅速暖化,有著一段差距。有些地方的氣溫長期趨勢是上升,近十年的狀況卻是下降;有些地方的氣溫一直穩定而持續的上升;更有些地方的冬季越來越熱,夏季越來越冷,年溫差越來越小。我們發現,就我們主要研究的東亞島國來說,暖化的幅度其實並沒有影片「正負2℃」所說的那麼大。

由蟲子問題衍生一路領先與Motzkin路徑之對應及推廣

在數學課堂中,老師拋出一道甄試的口試題目,那是一道有關蟲類繁殖過程\r 中,探討子代存在位置及其規律性的題目。此問題引起我們繼續討論的興趣,並\r 試著應用至「一路領先」問題。我們試著改變其形狀來構造「一路領先」的路徑,\r 再擴張其維度來解決任一人數「一路領先」的問題!\r 由於發現Motzkin 數列和三人「一路領先」給定得票數的情況一一對應,我們\r 找到一種對應方法,將Motzkin 路徑和「一路領先」得票過程做一對一的對應!以\r Motzkin 路徑和三人「一路領先」為基礎,我們構造了「立體Motzkin 」,發現其\r 路徑走法數竟和五人「一路領先」得票過程總方法數完全相同!若限制向量(1,0,0)\r 只能出現在xy 平面上,則和四人「一路領先」得票過程一一對應!當我們在網路\r 上搜尋資料時,發現有一種lattice path 的規則和四人「一路領先」的方法數完全\r 一樣!我們一樣找到一種對應規則,讓此走法和四人「一路領先」得票過程一一\r 對應!\r 架構出「立體Motzkin 」後,我們試著架構「n維Motzkin」,發現給定有規律\r 的(2n ?1) 個n維向量,就可以構造出n人的「一路領先」!此方法對解決lattice path\r 和投票問題等有顯著的幫助!

電容超音波膠體金粒子電位調控系統研發

費曼曾說:There is plenty of room at the bottom。喬治亞理工大學的Mostafa El-Sayed 教授發表的癌細胞辨識、與科學月刊報導『台大抗煞一號』引發我們對膠體金粒子的興趣。膠體的性質主要是由界達電位 (zeta potential)決定。參考台科大、成大、中山…等超音波應用研究,提出改良篩選物理法製造之膠體金粒子的儀器設計與製作。經沉降過濾可達平均粒徑 100 nm;而離心式篩選機與超音波管式篩選機可達平均粒徑30 nm。篩選後的膠體粒子以電容原理調控膠體金粒子之界達電位 (zeta potential),成功地從-30 mV 提升至-59 mV,並發展成電容超音波界達電位控制儀(Capacitor Ultrasonic Zeta Potential Controller)。以膠體金粒子與蛋白質鍵結量來測試調控界達電位的效果,發現蛋白質鍵結量之增加曲線與界達電位的增加曲線的增加趨勢相似;此功能的發現對於生物科技方面的應用應會有很大的幫助。透過界達電位控制系統,本研究達到費曼先生所期望的「在原子或分子的尺度上來加工材料和製造設備」。“There is plenty room at the bottom.” The words of Mr. Feynman are the beginning of nano technology. Mostafa El-Sayed, a professor of Georgia Institute Technology, identified cancer cells through nano gold-antibody complex. So, our study focuses on the zeta potential of colloidal gold particles. At first, the filtering method and equipments were developed. The theories were based on the ultrasonic studies of universities such as National Taiwan University of Science and Technology. Then the colloidal gold’s sizes were filtered to100 nm through settling. At last, by using Continual-Filtering Centrifuge (CoCe.) and Tube Well Mass (TW-MS), the mean particles sizes can be filtered to 30 nm. The most important results are: Zeta potential of the gold colloid was controlled with Capacitor Ultrasonic Zeta Potential Controller. The zeta potential can be raised from -30 mV up to -59 mV, which is -20 mV higher than the conventional pH-changing way. The function of zeta potential to protein binding quantity was tested. The increasing curves of zeta potential and protein binding quantity were similar. This property would be a significance of biotechnology. Thourgh Capacitor Ultrasonic Zeta Potential Control system, the zeta potential’s limitation of gold colliod, which is produced by SANSS (Submerged Arc Nanoparticles Synthesis System), can be controled in a wilder range. The study which is focused on nano-scale, like the wish of Mr. Feynman – “To manufacture material and produce equipment in atom and molecular scale”.