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平行五邊形

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斐疑所思-斐林世紀之謎

斐林是被使用超過百年的試劑,惟我們在實驗室中所得的結果(產物顏色),明顯與教科書不同;且酒石酸鉀鈉大量添加令我們疑惑,搜尋後得知其扮演配位基的角色,故欲了解銅離子與羥基間的配位,故針對下列兩點進行研究。 (1) 產物分析方面: a)斐林試劑分別與甲醛或葡萄糖,在不同溫度下反應,觀察反應狀況並分離產物。 b)以酒石酸鉀鈉添加與否作為變因,探討反應狀況。 c)以定性及定量的方法,比較各反應的產物成分。 d)依檢測出不同時間段的產物,來延伸討論其反應機制。 (2) 配位化學方面: a)Cu2+配位基之配位位置(官能基),及其配位條件。 b)NaOH在配位產生中扮演的角色。 c)延伸探討NaOH與糖類關係,並加以實用化。

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Tree'ting Wood Better:Sunscreen for Trees

The purpose of this experiment is to determine whether or not wood can be used as an alternative testing method for sunscreens and which species of wood are good for this objective. This will be accomplished by applying varying strengths, or SPFs, of sunscreens onto thin wood veneers. They will then be exposed using a weatherometer, in which real light and sun conditions will be simulated. Using a device called a Pulmac, the samples of wood will be pulled apart from the centre at zero span. Based on the consistency of the strengths, it can be determined how the wood reacts to the sunscreen and whether that species of wood is suitable as a testing medium. Trees are an important commodity which enrich the lives of many people, particularly those who live in British Columbia. They provide the means of living and recreation for numerous people, whether it is employment, business, housing, or camping. Since trees are a renewable resource, they are convenient and realistic to use for testing. There are two possible extensions to this project. If the active ingredients in sunscreens can be determined, then we may be able to use these elements to create a new type of stain for fences and other structures. This could make the necessity for painting less frequent, creating cheaper options for the homeowner. The second possible extension of this project is to use the results to as an initiative to reduce the amount of animal and human testing done by manufacturers. This is important, as animal testing not only causes unnecessary pain, but often the results are not very accurate. Overall, I determined that this method of testing sunscreens would work quite well, especially with the following species, listed in decreasing order. 1) Yellow Cedar 2) Yellow Poplar 3) Maple 4) Hemlock These results were based on how tightly grouped together the means of the strength values were for each species. The closer they were, the more consistent that type of wood and therefore the better they are for testing. Overall, I think this method of testing sunscreens would work quite well, particularly with the yellow cedar, maple, yellow poplar and hemlock, as they resulted in fairly consistent strength values. Generally, the sunscreens with a high SPF, or Sun Protection Factor, resulted in a lower strength loss than the sunscreen with SPF 15. In addition to proving that sunscreen is a good method for preventing UV rays from reaching the skin, this experiment has also confirmed that there are other methods of testing sunscreens, which can be researched further. Along with my main presentation I will be showing various graphs, statistics, and pictures. They will be supplemented by a booklet of “Commonly Asked Questions and Answers” and species descriptions for each type of wood.

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超音波霧化降溫之研究探討

本研究(超音波霧化降溫研究)由二實驗組成。實驗一主要針對超音波霧化器(以下簡稱霧化器)之造霧性能進行探討;實驗二則為霧化器之降溫應用。實驗一以改良傳統造霧方式,進而維持最佳造霧效果為主。由於先前的霧化方式是直接放置霧化器於水面,致使最佳霧化水深因霧氣蒸散、水位下降而無法維持;所以在實驗一裡,我們針對霧化器的使用設計一套「漂浮造霧法」:本法運用浮體使霧化器懸於水面,和水面等起伏,使霧化器底部距水面高度不變,藉以維持最佳造霧水深、造霧效果。實驗二乃霧化降溫之探討。本實驗在相同的霧化量下,操縱風速和接觸表面積的差異;利用霧、氣接觸面積與蒸散速率呈正向關係的原理,找出最佳的降溫條件。同時,也期待在兼顧環保的前提下,將之應用於未來開放空間的降溫。The research(Heat Control by Supersonic Vaporization)includes two experiments. One is focused on atomized effect of Supersonic Vaporization(so-called Atomizer); the other is about applying atomizer to temperature decrease. Exp.1 adapts formal way of atomization. Since previous way of atomization is to put atomizer directly on the water, making the change of atomizer’s distance from water as water evaporates, Exp.1 creates a way called “Floating”. In Floating, atomizer is suspended in a float; constantly keeps the bottom of atomizer from same distance from surface of water. Thus, no matter how much volume of water is evaporated, the best depth of water for atomization and also, the best atomized condition, could stay. Exp2 inquires in relation between atomization and temperature decrease. In Exp2, the atomized volume is fixed, while wind speed and air-contact area are mastered elements. By the theory that, “the wider contact area is, the more efficiently water evaporates,” we could manage out the best condition in temperature decrease. In that way, with the theory practiced, this research, considering environmental case, is supposed to be applied to open-air area one day.

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龍捲風(Tornado)形成之理論探討及模型建立

曾看過一部電影叫做「龍捲風」,是由史蒂芬史匹柏導演拍攝,影片中之龍捲風精彩壯觀,橫掃過的地方,滿目瘡痍,造成很大的損失,全劇描述一位科學家由遭遇突如其來且威力強大的龍捲風而毀損,長大後立志從事龍捲風的研究救人,她和她的隊友們冒著生命危險正面進入暴風圈,成功投放測試器,從而了解龍捲風的構造,進而希望建立龍捲風警報系統,那種鍥而不捨的精神和意志力令人印象深刻; 然而我們在台灣僅偶而聽到新竹、嘉義、左營等地方曾發生龍捲風的新聞報導,卻不易親眼看到,於是我們想:何不製作一個可以產生龍捲風的模型,讓同學們想看能看到,那就太炫了!

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螞蟻的研究

前天林伯伯送來一盒林姐姐的訂婚喜餅,餅上滿是小螞蟻,連盒搖了半天還是沒有弄乾淨一一螞蟻真是討厭。第二天我到學校也聽幾個同學說:「放在櫥裹的糖也常跑進螞蟻。我們想如果有簡單的方法能避免螞蟻來偷襲及能知道有關螞蟻的生活情形和種類等,那多好,因此就請教級任鄭表師,老師說:「這問題很好,讀我們一起研究吧!」

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蜘蛛

每當打掃清潔區的時候,同學們常被蜘蛛網黏得滿頭是蜘蛛絲,有時候想消滅牠,但又找不到牠躲在什麼地方?把網清除了,明天又結了一個新網。自然課本裹對這紡織的能手也沒有詳細的提過,因而引起了我們對牠觀察研究的興趣。

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舒適的高空之旅--探討貓空纜車車廂通風方式與空氣對流、溫度的關係

貓空纜車車廂在通風方式進行了三個階段的改善,究竟效果為何?又有多少效益?而在\r 夏天車廂行進時該以何種通風方式最好,冬天又該以何種通風方式最佳?經由實驗與數據的\r 分析結果,我們得知夏天搭乘纜車行進時,想要最涼爽、最舒適的通風方式,就是將迎風面\r 上方的兩扇窗戶都開到最大為九十度,同時也把車廂門上方的窗戶打開,而將背風面上方的\r 窗戶關閉。冬天希望保持車廂內通風,但又不會覺得寒冷,則以穿保暖的衣物再將迎風面上\r 方的兩扇窗戶都開到為四十五度,同時也把車廂門上方的窗戶打開,而背風面上方的窗戶也\r 打開,為搭乘纜車時最佳的方式。而在夏天纜車車廂行進時,比起車廂全部封閉的情況,改\r 善後的最佳通風方式可高達48.68%的效益。

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由Brocard Point 發現幾何不等式

本研究報告以Brocard Point 為核心,所用到的性質均先證明,以確認其正確性,並推演出一些其他的性質,藉由這些性質導出幾何不等式。內容可概分為四部份:(1)以Brocard Angle 及已知的或推演出的基本性質,導出一些不等式。(2)結合「法格乃諾問題」、「費馬點」、「尤拉公式」導出幾個幾何不等式。尤其是三角形邊長與面積,外接、內切圓半徑與邊長間的不等關係,頗為有趣。(3)以向量為工具,分別計算內、重、垂心與Brocard Point 間的距離,並導出邊長的不等關係。其中由內心及重心所導出的不等式,清楚俐落;垂心所導出的不等式則較為複雜。(4)以Brocard Cirle 與內、重心間的關係,導出一系列的不等式。其中Weitgenberk 不等式的無意發現,令我們印象深刻。The Discovery of Geometry Inequalities by Brocard Point This paper takes Brocard Point as a core. We proved some properties about Brocard geometry to confirm its accuracy, and deduce some other properties, and then derive some geometry inequalities by these properties. The content may divide into four parts: a) Derives geometry inequality by Brocard Angle, Crux Mathematicorum and properties which known or deduced. b) Unifies "Fagnano problem", "Fermat Point", "Euler formula" to derive several geometry inequalities. In particular the inequalities between triangle area and length of side, or circumradius inradius and the length of side, is quite interesting. c) Derives geometry inequalities about length of sides in triangle by the distances between incenter centroid circumcenter and Brocard Point. Especially, these inequalities were elegant which derived by incenter and centroid, but it was complicated derived by orthocenter. d) According to the relation about incenter centroid and Brocard Circle derives a series of inequalities. Discover Weitgenberk inequality makes us excited.

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廢絲襪也有春天—絲襪的回收再利用

我們利用家庭裡常見的廢棄絲襪,將之回收再利用。絲襪中的耐綸成分可溶於甲酸,經純化、脫色後即可得到耐綸溶液。我們將耐綸溶液均勻滴加於玻片上風乾,得到自製薄板層析試片(TLC片),可運用於生物及化學實驗中混合物的分離。分離後的物質亦可通過儀器做定性及定量分析。 耐綸的化學結構含有醯胺鍵,我們從早期的科展報告中發現重金屬鹽類易與蛋白質結合成穩定的沉澱物而析出,得知蛋白質因含有大量醯胺基團,能與金屬離子結合成蛋白質鹽沉澱,藉以除去水溶液中的重金屬。我們利用同樣含有醯胺鍵的自製耐綸溶液進行重金屬吸附實驗,期望能夠達到吸附並除去重金屬的效果。本實驗所使用的材料是家中舊有的尼龍絲襪,以達到廢物利用及環保的最高宗旨。

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日本菟絲子與平原菟絲子寄生現象之觀察

菟絲子屬於高等寄生植物,危害農業作物,其特殊的寄生方式與其他綠色自營性植物非常大的差異,具有特殊的科學研究價值。菟絲子會產生特殊的吸器(haustorium)侵入寄主體內奪取生活所需的養分及水分。本研究經由現場調查、斷莖及種子培養台灣近年來中部地區頗為猖獗的日本菟絲子(Custuta japonica Choisy var. japonica)與平原菟絲子(Custuta campestris Yunck.)以瞭解其生活史,發現極為獨特的自體寄生及重複寄生現象,日本菟絲子主要是由斷莖傳播;平原菟絲子主要由種子傳播。使用石蠟切片發現兩種菟絲子都會產生特殊的一群分生細胞,稱為刷狀細胞侵入寄主組織連通至寄主維管束奪取寄主水分及養分。

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荖溪河畔風雲可測

老師上自然課對我們說:觀測天氣,把觀測結果紀錄下來,如果能繼續不斷,並把紀錄好好的保存起來,我們就會發現許多有規則的天氣變化,久而久之也可預側未來的天氣變化。歷史上孔明借東風就是一最好的前證。又氣壓、溫度、風向 …… 等也和天氣的變化有相當的關係……。」當時我心裹暗想,如價如此,我當叮成為再世孔明,因此引起我紀錄研究氣象的興趣,並竭力有恆的去做。」

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