全國中小學科展

臺灣

薑黃素的特性及其在生活上之應用研究

本研究在探討薑黃、南薑、野薑及一般薑等所含薑黃素的抑菌與抗氧化作用特性,及其在生活及教學上之應用。研究發現:(1)抑菌能力排序:以薑黃最強;一般薑次之;南薑、野薑微弱。(2)抗氧化作用仍以薑黃最為明顯,其餘不顯著。(3)在生活上之應用方面,薑黃素用於檢測水質及食品中是否含硼砂,可明確檢出含硼量;薑黃素所含的天然色素,可用於布料之染色及食品用色素添加劑,亦可用於製造薑黃手工皂,對人體皮膚有益處。(4)在化學實驗上,薑黃素製成薑黃試劑,可做為酸鹼指示劑,另可檢驗一般居家物質之酸鹼性。由以上實驗結果可知薑黃素應用甚為廣泛且深具利用價值。

傑克船長的心機'

作者受考題( International Mathematics Tournament of the Towns, Senior A-Level Paper, Fall 2009, No. 7 )?發而展開此研究。經搜尋文獻發現,這系列命題可追溯自 Scientific American ( Feb 1979 )中 Martin Gardner 的文章 The Rotating Table 。\r 命題之操作原在正方形桌上執行,後被Ted Lewis & Stephen Willard 推廣至正多邊形(1980),又再被Richard Ehrenborg & Chris M. Skinner推廣至任意置換群(1995)。\r 本文從均勻多面體的情形出發,藉諸自創的證明方式,重新詮釋上述論文之結果,給出較簡潔自然的證明。同時,作者改變命題裡的關鍵限制,發展全新的研究方向;並針對不同的情形(多邊形、多面體、置換群)分別求出各變數之上、下限。\r 本文使用到的技巧包括:群論、歸納法、組合設計。充分性之證明過程提供的演算法能應用於同步連絡管道,允許匿名用戶之間建立連線。

反正切函數,二階線性遞迴數列與疊在一起的方格紙

本文由三個結合 tan−1 與費波那契數列的等式及其所搭配的無字證明圖形出發, 做出和盧卡斯數列有關的圖形, 並由數學歸納法找出並證明 tan−1 與盧卡斯數列及一般二階線性遞迴數列的全新等式: This paper startes with three equations of tan−1 and the Fibonacci sequence combined with the diagrams used to prove the three equations without words. According to the principle of mathematical induction, we continued to find out the similar equations of the Lucas numbers and the second-order liner recursive sequences as follows.

水生開花食蟲植物絲葉狸藻捕蟲囊構造及共質體輸送

水生食蟲植物絲葉狸藻 (Utricularia gibba) 是非常獨特的,它不但跟其他植物一樣能行光合作用,且具備捕蟲囊捕捉水中小生物,補充生長所必需的營養元素。捕蟲囊的構造精密卻不複雜,消化吸收主要靠囊內壁上的四爪腺毛,目前尚未有文獻實際以追蹤物質描述出整個共質體輸送路徑。我們是最先以螢光染劑 (carboxyfluorescein) 及共軛焦雷射掃描顯微鏡(confocal laser scanning microscope) 成功地描繪出捕蟲囊共質體運輸路徑。同時我們也以對細胞無害的食用色素,進行相同的實驗觀察。發現食用色素不但成本低,且較螢光染劑有更多的優點,如觀察時間較不受限制等,非常適合用來研究捕蟲囊吸收物質的路徑,因此,本實驗的模式可以應用在其他水生植物運輸路徑的研究。;The aquatic carnivorous plant Utricularia gibba is very unique. It has not only the ability to undertake photosynthesis just like other plants, but also can trap and obtain the nutrients from the freshwater zooplankton. Its trapping organ is very sophisticate but not complicate. The digestion and absorption process inside the trap are mainly accomplished by the quadrifids structure. According to our knowledge, we are the first to introduce the phloem-mobile, fluorescent probe carboxyfluorescein (CF) and confocal laser scanning microscope (CLSM) to the study of the symplastic transport in the Utricularia trap. In addition, we use edible food colorings as tracers for this transport study. Both approaches turn out to be very successful in delineating the symplastic transport of the trap. But CF quenches rapidly so the observation time is restricted. On the contrary, food colorings don’t have these disadvantages; it is inexpensive, easy to perform, and the transport process is not fast. As a result, the study is easily to be completed. These methods will be very helpful in the studies of symplastic transport in other plants.

水漂的物理現象之研究

本研究主要探討水漂彈跳的物理現象,在研究中我們以實驗配合理論,藉由分析不同變因的影響,找出水漂彈跳的最佳模式。在實驗中,我們自行設計並改良發射器,並改變水漂發射的各項變因:包含初速、轉速、及發射仰角,另外也針對不同錐度的水漂進行實驗。同時,自行開發近景攝影及相片分析的技術,以進行測量及分析。\r 我們由實驗得知水漂在擁有較大的初速及轉速時,可有較大的彈跳次數。另外,在相同速度時,發射仰角越靠近20度~25度之間越容易彈跳,且有最低的最低彈跳速率。此外,我們發現使用錐度5度的錐形水漂時可增加彈跳次數,並會產生明顯的滑行現象。\r 在理論分析中,我們針對水漂與水面接觸瞬間的受力進行探究,並根據實驗發展出一套在給訂初始條件時可推算出彈跳次數的方法,適用於我們所用的水漂。

密碼鎖-拉丁超立方體的完美控制情形(Lucky Locks)

有個密碼鎖由D個旋鈕組成,每個旋鈕有N種不同的號碼,由於構造缺點若D個旋鈕中僅有1個號碼錯誤仍能打開密碼鎖,問最少嘗試多少組號碼才能保證一定能打開這個鎖?這個問題等同於在N元D維超立方中找一組點集,點集中的點各自向其D維度畫出延伸線,若超立方中的所有點都至少被1條延伸線所涵蓋,要求重複涵蓋的次數總和要最少。\r 43屆的科展中已經討論過3個旋鈕的情況,我們接著分析4個旋鈕的情況。在討論中發現D=4時並沒有如D=3時保證打開的最小次數公式,我們給出上下限的公式。但D=N+1且N≠6時卻很特別,恰可利用拉丁超立方挑出1組點集,其所有延伸線涵蓋的點都沒有重複,稱為完美控制,而保證打開鎖的最小次數是NN-1。

熱巧克力效應之迷思

“熱巧克力效應”是當你將巧克力粉加入裝有熱水之馬克杯後用湯匙輕敲杯壁,可以聽出攪拌前後敲擊所得聲音頻率明顯不同,攪拌後巧克力粉溶解頻率會較高。一般論文的解答是「當粉末溶解的時候,藏在粉末裡的空氣就會跑出來,在空氣與水混合的環境裡,音速比在水裡低。當水裡不斷有空氣與水混進去時,這個容器的共振頻率和它裡面的音速有關,所以也會降低。因此你會聽到較低之音調,直到空氣全跑光。」但根據我的實驗我覺得這樣的解釋並不對。我們提出新的模型來解釋“熱巧克力效應”。When we put an ounce of dry chocolate powder into a mug filled with hot water, then tapping the side with your spoon will generate a sound. The pitch of this sound will rise after stirring. This is called “the hot chocolate effect”. According to a published paper, the explanation is “The air trapped in the powder is released as the powder dissolves. Since the speed of sound is lower in air than that in water, the speed of sound in the air-water mixture is lower than that in pure water. During that period while the air escapes the container, the resonant frequencies of the water, which depend directly on the speed of sound, will also be lower. Hence, you hear a lower tone until the air escapes”. However, our experiments clearly demonstrated that the explanation is plainly wrong. A new theoretical model is also proposed for the observed phenomenon.

棉花糖『懼高症』

專題課時,利用20根義大利麵及有限的膠帶與棉繩搭高塔挑戰失敗,引發了我們對在有限資源下,如何搭出堅固高塔的好奇心。本研究利用自然課的教具完成簡易裝置,測試了幾種市售麵條的彈性與彎曲強度,挑出適合的義大利麵條進行棉花糖挑戰。接著使用圓竹棒代替義大利麵進行結構的實驗,再配合自製的剪力測量裝置進行研究,探討三角形長邊的重疊方式對剪力與耐重力的影響,並發現剪力與耐重力最大的重疊方式與加強三角柱的直立柱中間點可以加強耐重力。最後,運用研究結果與文獻資料,成功將20根義大利麵高塔由原本22公分高提升到97公分高,高度增加了四倍多。

大自然的奧妙~土壤自我淨化能力

大氣圈、水圈與土壤圈是構成自然環境的三大領域,三者之間相互的影響,原本這些空間都具有極大的包容力,亦所謂「自淨能力」,許多的物質進入其中皆會被氧化分解或稀釋而消失於無形。近年來由於工業發展、人口增加,產生大量的廢棄物,長期、密集且迅速的堆積於環境中,使得天然的自淨能力無法應付而失去功能,造成嚴重的後果。就土壤而言,雖有較佳的自淨能力,但是一受污染,除了嚴重破壞土壤品質之外,同時也會直接或間接污染水源 (如:地下水)及空氣,對動植物造成危害,並且難以回復,實不容忽視。本實驗探討:一、土壤淨化能力是否受到不同地區、不同土壤性質的影響。二、同樣的土壤,對不同的污染物(色素、肥料、重金屬)淨化能力強弱的影響。實驗結果顯示大肚山土壤過濾溶液中的色素、磷、及重金屬中的鉻、鎳、銅的能力較中寮及大甲土壤強,只有氮與鉀的過濾能力較大甲土壤差,所以這次實驗中大肚山土壤有最好的污染淨化能力。實驗結果將來也許可以應用於土壤處理場址之適宜性評估。The air, water and soil are three parts of the nature. They affect each other. In fact, they have the "self-purity ability" - they can disassemble many polluted thing by this kind of self-purity ability. These years, because the industry development and the population explosion make lots of waste, the self-purity ability cannot do its best. The soil has better self-purity ability, but if it is polluted, it will not only pollute the water (ex: underground water) and the air, but also damage the animals and plants. We cannot ignore the serious result. This experiment will discuss:1. If the soil self-purity ability is affected by different area and different soil specificity? 2. The different purified results according to the different pollutant (ex: color, fertilizer and heavy metal) in the same soil. Results showed that Da-Du-San soil had strong ability then Chung-Liao and Da-Cha soil in filtrated color, phosphor, chromium, nickel and copper in the solution, but had weak ability then Da-Cha soil in filtrated nitrogen and potassium. Therefore, Da-Du-San soil had the beast pollution-purity ability in this experiment. In the future, results may be applied to the suitability evoluation of the soil treatment place.

滴水不漏-冷氣水回收應用分析

當我們在開車享受冷氣同時,此時冷氣水正一滴一滴的滴水,造成水資源的浪費,在環保意識抬頭的今天,我們即針對此一問題進行研究,主要將冷氣水回收起來,並運用在補充雨刷水箱或者提供引擎水箱或冷凝器降溫作用,是否達到提高引擎工作性能及降低冷氣冷房效果,進而達到「資源回收」的。實驗結果證明在補充雨刷水系統最符合環保概念;另在引擎水箱噴水作用時,可縮短風扇運時間並增加停止運轉時間,可增長風扇使用壽命,對下水管溫度亦可降低,可防引擎過熱;在冷凝器噴水作用中亦能明顯提升汽車冷房效果。When we enjoyed driving with cool air from air-conditioning, the condensed water from air-conditioning system is dripping from the system drop by drop. It caused the issues of the waste of water resource. Facing the greater public awareness of environmental protection issues in Taiwan, we are focusing on this issue to have further research. The idea is to re-cycle the air-conditioning condensed water and re-fill it in the water tank of wipers, the water cooling tank of engine or the cooling system of condenser. The purpose is to improve the performance of engine and enhance the cooling efficiency of air-conditioning system. It is helpful to meet the objective of water resource recycling. The result of experiment has shown that re-filling water in the water tank of wipers meet the goal of environmental protection well. Also, the water injection in the water cooling tank of engine could reduce each operation time of cooling fan and increase the idle time of cooling fan as well. It prolong the equipment life of cooling fan and lower the operation temperature of Low water pipe which prevent the engine overheating. Meanwhile, It is proved that the water injection in the cooling system of condenser can enhance the cooling efficiency of air-conditioning system.