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飛 ㄉㄢˋ 、 飛 蛋 -----古代飄浮蛋解密之一
Discovery 頻道報導:早在西元前2 世紀,漢代淮南王劉安的《淮南子‧外篇‧萬畢術》就有「艾火令雞子飛」的記載,注:「取雞子,去其汁,燃艾火,內(納)空卵中,疾風因舉之飛。」去年(92 年)的國小科展作品證實 Discovery 頻道的報導有誤,空蛋殼用線香的熱氣浮力是飄不起來的。但是「……疾風因舉之飛。」這句話讓我們想到:利用熱氣球的熱氣浮力並不能造成「疾風」;而水火箭或是火藥的噴射「疾風」,也就是作用力與反作用力原理,應可以造成蛋殼的噴射。經過我們的研究結果發現:一、 燃燒產生熱氣的浮力,連蛋膜都無法漂浮,更不用說使蛋殼飛起來。甚至高溫還會使得蛋膜焦黑萎縮。可見熱氣球原理無法使用。二、 利用自製小型密閉水火箭的噴射原理,測試要使6 公克的蛋殼噴射,至少要1.92 個大氣壓才能射高2 公分。但是蛋殼灌氣加壓至1.28 個大氣壓起,就有可能會爆裂,更不可能彈射近一人身高的高度。三、 為避免壓力過高造成蛋殼爆裂,接著我們改用火藥噴射原理。發現:1. 噴射口如果大於 1.2 公分則噴氣力量分散,無法噴射起飛。2. 火藥量若超過 0.4 公克,所產生的氣壓會造成蛋殼爆裂。而單純利用火藥噴射,就如同發射空的水火箭,大都噴射不到10 公分高。3. 若加入砂子一起噴射,則0.36 克的火藥量以及1.5 克的砂子並在噴射口塞上0.03 克的棉花,所產生的反作用力及噴射效果最佳,蛋殼彈升的最高紀錄曾數次達1 公尺以上的噴射高度,而且砂子在蛋殼底部維持重心,更容易造成垂直的起落。由本實驗結果推論:古書中所敘述的「取雞子,去其汁,燃艾火,……疾風因舉之飛。」應是最早的火箭原理的應用,而非應用熱氣球原理的開創者。本實驗設計正是提供學生引起動機學習牛第三運動定律的最佳探究教材,是「作用力與反作用力」的最佳實驗例證,值得推廣!也證明古代中國科學文明的昌盛!
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The research of Ube anthocyanin characteristics and utilization
Anthocyanin is a water soluble pigment that may appear in various colors such as red, blue, and purple according to the pH. Ube is a fruit in the Philippines that is 3rd of the most cultivated crops. Since Ube contains a lot of anthocyanin, it helps to make the anthocyanin solution. As Anthocyanin reacts to the oxygen quickly it is also used as air pollution indicator because it changes its color according to what substances they are attached to it. To check if the solution reacts to the pollution such as SO2 and NO. When those pollutions are made artificially, examining the intensity of the anthocyanin solution depending on different Mol of the pollutions was able. The power of penetration of lights though the UV-VIS spectrophotometer increases according to the number of molecules of SO2, and also NO. To examine the change of intensity of anthocyanin solution in actual atmosphere, the solutions were exposed outside for several hours. The power of penetration decreases when exposed to an actual atmosphere. The other substances and oxidation were the causes of the changed in color of the solution To facilitate the usage of anthocyanin solution efficiently, it should be preserved, so that the density of specific color will be preserved when used as real air pollution indicator. In order to check what kinds of chemicals can preserve the anthocyanin solution; different kinds of strong acids, strong base, salts, and metals were added to the solution. After getting the data, the characteristics of the chemical which preserved the anthocyanin were scrutinized, than compared to the density of pure anthocyanin solution. To use anthocyanin as air pollution indication as a solid, the Korean traditional paper and cloth were dyed using ube which contains lots of anthocyanin than checked the pixel of red, green, and blue color. Firstly, chose 6 different salts. And then filter and boiled the anthocyanin solution. And then put each different salt in each paper. After that, dried the paper and check the difference of pixel of each paper. As a result, Calcium hydroxide (CaOH2) has highest pixel point. So, using calcium hydroxide to dye clothes is useful and it’s also useful for the air pollution indicator through the experiment. Especially it reacts to Nox and Sox, according to this experiment, it can use for eco-friendly air pollution indicator.
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