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石頭蟲、瓜子蟲、兩頭蟲?聰明的建築師─衣蛾是也!
衣蛾屬鱗翅目、榖蛾科,是一種完全變態的昆蟲。生命週期包括卵、幼蟲、蛹、及成蟲,生命週期約 5-6 個月。衣蛾的主食是頭髮,其次選擇兔毛、羊毛、及雞羽毛。衣蛾會儲存食物在殼內。此外,水分對衣蛾非常重要。造殼的方法有兩種,一種是剛孵化和被拆殼的衣蛾,先鑽進砂子或羊毛,吐絲成雛形殼,然後拖著雛形殼,取砂子由一邊開口作到另一邊。另一種是衣蛾擴增外殼時,將殼的側邊部份咬開,吐絲並抓取小砂子,以同心瓜子形的方式,擴張其殼。材質有碎玻璃、小磚塊、小石子等。台灣的衣蛾偏向用砂子作殼,若無砂子,衣蛾仍可造出羊毛外殼。衣蛾與蜘蛛沒有互利互害的關係。衣蛾的天敵是小繭蜂。大量的螞蟻會對衣蛾造成威脅。
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承諾一個乾淨的未來-太陽能磁浮馬達和高效率磁浮小型電動機及風力發電機
本實驗利用磁鐵同性相斥的原理,結合馬達,減少摩擦係數,以期製作類永動機。第一代原型太陽能磁浮馬達使用了隨手可得的資源製作,為符合環保效益的馬達。經過設計改良,有了可立可臥第二代機。因仍希望能再減少機械耗損,提高效率,於是利用切割線圈的原理製造小型風力發電機,及以霍爾感應器取代傳統電樞,製作無碳刷馬達,製造了結合發電與電動功用的第三代高效率磁浮小型電動機及風力發電機。其具有減少摩擦,降低能量損失的優點。與市售馬達比較,大幅減少振動與噪音的問題。因無潤滑問題,容易維護,又可外接太陽能板驅動馬達,以風力發電,符合環保綠色效益。希望我的創作能為地球環保盡一份心力。
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綠色化學實驗-利用溶劑特性回收實驗後的硫酸銅
利用99%丙酮及95%酒精可以把硫酸銅晶體從實驗後的廢棄水溶液中取出來; 如同搾汁機一般,將硫酸銅結晶從水溶液中析出,其析出率可高達95.0%~90.0%。不需要外加能源,只需加入適量體積的丙酮、酒精溶劑靜置24小時不用攪拌,一顆顆漂亮的硫酸銅晶體就析出沉於底部。經過簡單的過濾及烘乾硫酸銅晶體就可以回收再利用,過濾的溶液經過簡易的蒸餾也可以回收丙酮及酒精,留在下次重複使用。如此便能解決化學實驗室硫酸銅廢液的儲存及處理。此種流程也可以用於,部分含有無機化合物的廢棄水溶液。簡易安全的操作,可回收再利用,減低衍生物的產生等,是綠色化學實驗的目標。By the use of 99% pure Acetone and 95% pure Alcohol can take the Copper Sulfate crystal out of the waste solution, as the way that juice press operates to separate the Copper Sulfate crystal from the solution. The rate or the separation can high up to 95.0%~90.0%.Without the need of extra energy, simply add proper mass of solvent like Acetone or Alcohol(refer to Result and Discussion) and place it 24 hours without stirring. Beautiful separated crystal can be recycled and ate capable to use again. By simple distillation, the filtered solution can recycle the added solvent such as Acetone or Alcohol which can also reuse next time. By doing so, the problem of storing and managing the waste solution of Copper Sulfate in laboratories of Chemistry will be solved. This procedure can also be used in parts of the waste solutions which contain inorganics. Simple and Sage operation, the capability of recycling and reusing and reducing derivatives etc., are the goals of Green Chemistry.
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為了讓添加了糖的飲料喝起來更健康,我們藉由實驗更深入的了解糖的糖度、糖的熱量,也了解到甜度是一種感覺,真正與熱量有關的是糖的濃度。我們藉由討論糖度計的原理,嘗試自製了「簡易折光式糖度計」和「旋光儀」,用來檢測糖的濃度,並以燃燒糖的方式,研究糖的熱量釋放,最後比較含糖飲料的糖濃度與熱量的關係。經由實驗發現以自製的簡易折光式糖度計測量可發現糖濃度越高時,光的折射角度越小,而糖的旋光性效果也會與糖濃度有關,飲料中糖的濃度高時通常熱量會高。
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探討電磁鐵裝置中線圈纏繞的形狀與磁力大小之關係
本作品目的在於探討小學自然與生活科技教材有關電磁鐵裝置之內容,其線圈纏繞的形狀與電磁鐵磁力之關係。實驗小組利用自行設計之實驗設備操作實驗,自製4 種外圍周長相同、但形狀不同的中空柱體,分別以相同長度之導線纏繞相同的圈數做成各式電磁鐵,再利用砝碼及迴紋針做為測量磁力之工具,得到「相同線圈數之情形下,所繞的線圈之形狀愈靠近圓形者,其產生的磁力愈強」之結論。實驗小組並針對線圈纏繞之中空管的粗細大小對磁力的影響提出現象的探討,得到「磁力的大小與中空管的粗細並無直接關聯,透過電阻與電流的測量,通過線圈之電流大小才是影響磁力最重要的因素」之另一結論。最後,實驗小組利用穩定之電源供應控制,設計一嚴謹之操作步驟,以維持實驗結果之穩定性。最後針對電磁鐵各種變因與磁力的影響,提出了現象的觀察心得。
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一、研究一般植物在不同的溫度下的光合作用。二、測定照度對植物光合作用強弱的影響。三、測定各種色光以及紫外線,紅外線對植物光合作用的影響。四、綜合溫度,照度,色光等三因素,對一般植物光合作用的交互影嚮並求其三因素的最佳配合點。五、解決國中生對植物光合作用實驗的困難,使光合作用實驗可完全在人為的環境下實施。
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目前社會都市化的建築越來越多,相對的排水管轉角越多排水系統越來越複雜,使得浴室排水孔常因毛髮而阻塞,本研究是要解決浴室排水孔被毛髮阻塞的問題,然而目前市面上產品皆只是在排水孔上面加上其他的阻隔物,加上隔物後排水效果變差、並且有積水現像,並且還有少數毛髮從空隙中流入排水孔中,所以要徹底解決毛髮阻塞及相關的問題,不僅是加阻隔物更應從排水孔蓋著手,重新設計方能有效解決問題。市面上並沒有針對排水孔蓋做重新的設計,本研究針對改善重點提出:下凹式的排水孔蓋改善積水,並在下凹邊緣處在加工成內凹槽的型式以卡住濾網,為使排水效果不因濾網而降低,所以也原 11 個落水孔改為 9 個落水孔,並且加大落水孔,以全新的設計徹底解決毛髮阻塞及相關問題,當製作完成後,經實際使用測試比較,確實比市面上相關產品的效果還好,也沒產生其他問題。
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延續38 屆北市科展的研究主題繼續研究,針對實驗方法進行改良。用熱敏電阻、數位電錶、冰箱冷凍庫、不同水溫,測繪「冷卻曲線」探討彭巴效應。發現在80℃、60℃、40℃、20℃的不同水初溫中,初溫愈高的水,完成冷涷的時間愈短。由冷卻曲線觀察,發現初溫較冷的水比熱水有更明顯的過冷現象。由冷卻曲線觀察,彭巴效應非常明顯,並且可由曲線上準確量測結冰始末的時間。彭巴效應明顯,並可重覆實驗。這次的研究探討,有助於我未來在彭巴效應實驗的量測技術。可應用於一般家庭冷卻物品時,快速冷卻,節省時間。可找出結冰的經濟初溫範圍,提供往後各領域利用. Hot water freezes faster than cold water? It is surprising to most people, but it is true. It has been observed and studied in numerous experiments. I tried to set up an experiment to explore the so-called Mpemba effect. I use NTC, multi-meter and house refrigerator to construct cooling curve for water of various initial temperature. The Mpemba effect is discussed based on the cooling curve. I found that the benefit of using NTC is faster measurement, higher sensitivity and cooling process is not disturbed. By inspection of the cooling curve, the Mpemba effect is obvious and repeatable. The initial and final state of freezing process is easily determined. Cold water reveals super-cooling phenomena. Inspection of gas bubbles in freeze ice showed that cold water contains more gas than hot water.
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界面活性劑因分子一端具極性基(polar group)而有導電性,本研究以市售之界面活性劑(PAOS洗碗精)從事其水溶液導電度探討,實驗顯示,PAOS水溶液之導電度隨溫度升高而增加,90°C之導電度約為常溫之三倍,純水之變化則極微。除溫度外,界面活性劑濃度亦影響導電度,濃度越高導電度越大,定溫(23°C)之導電度隨PAOS含量增加呈直線上升關係,PAOS含量每增2%導電度約增加1000μS,當含10%PAOS之水溶液中期導電度約增為4700μS。乳化效果對導電度亦有明顯之影響。在含PAOS 0.5~3%之水溶液中加入沙拉油,隨沙拉油加入量之增加其導電度均呈現下降現象。例如,在含有PAOS 3%之200克水溶液當中加入10克沙拉油時,其導電度約下降了15%。如果加入更多沙拉油,或者乳化攪拌過後之停滯時間過久,造成乳化平衡破壞,其導電度數據則較不規則。因此,我們可由溶液導電度之量測結果判定乳化效果,並可測定乳化攪拌之最佳條件。實驗除了以導電度探討其乳化效果外,並用顯微鏡同步觀測,以對結果做出更具說服力的解釋。將實驗數據以3D圖(立體圖)呈現以描述系統的連續變化狀態。再利用簡易的曲線回歸、斜率比較等,判定在定溫、一定攪拌條件下,清潔劑的較佳使用濃度。Surfactants have polar end groups at its molecular structure lead it with electrical conductivity in properties. This report discuss conductivity of a market purchasable surfactant named PAOS. Experiment results indicate conductivity of PAOS water solution increases with rising temperature. Triple in conductivity of this solution was found at 90°C than that of at room temperature. While the changes for pure water is very small. Except temperature influence, surfactant concentration also influence its conductivity. Generally, higher concentration gives higher electrical conductivity. At room temperature(23°C) a straight line relationship was observed between the solution concentration and the conductivity. For every increase 2% will led to increasing in conductivity for 1000 μS. When 10% PAOS in water solution is reached 4700 μS in conductivity was observed. Emulsification give obvious inference in conductivity. If cooking oil is added in 0.5~3% PAOS solution, conductivity will decrease with increasing oil added. For instance, when 10 grams of oil was added in 200 grams water solution that contain 3% PAOS, conductivity of this solution decreased for 15%. If more oil is added or setting time is too long after the solution is emulsified that destroy the emulsify balance. The conductivity of the system become irregular. In this way, it is possible to detect effect of emulsify through the measurement in its conductivity. Therefore most favorable condition in emulsification can be determined. In addition to using conductive measurement to determine effect of emulsification, microscopic technique also used trying to find even more convincible explanations. The data of different concentration experimented above can be presented on a 3D chart, we obtain several curves that can be differentially analyzed and estimated for a relatively ideal concentration, which will work more efficiently than others in the condition of the experiment.
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