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熱門關鍵字: the king 水果 豆漿 電腦 䰾
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周轉不靈(汽車過彎翻覆原理與對策)

「翻車」事件令人怵目驚心,輕則車毀,重則人亡。減少翻車事件,可減少悲劇的發生。而翻車絕大多數均發生在轉彎的路段,且伴隨著超速發生。因此,本研究乃針對汽車過彎行駛,探討其翻覆的原因以及改進之道 · 本研究乃利用實驗分析法以及理論驗證法進行研究,實驗中變化不同的汽車質量,車軸寬、車身高以及車軸寬/車身高,質量重心寬、高以及寬/高、傾斜度以及迴轉半徑等九種參數 · 於自製的紅外線偵測變頻式可調迴轉模擬機上以八部模型試驗車測試其翻覆轉速,並換算為翻覆速度後逐一分析討論之。經由實驗結果,本研究得到以下結論:一、汽車轉彎翻覆與離心力有關,當離心力大於臨界側向推力時,汽車即翻覆。臨界側向推力公式為 F = mg ( tanθ + K?) / ( l -K? tanθ ) 二、最大容許車速平方與轉彎半徑及質量中心寬高比相乘積成正比;而在定車速下,飲小客許轉彎半徑與質量中心寬高比成反比.前述各項皆與質量大小無關.三、提高轉彎路面傾斜度對防止汽車翻覆有確實的效果。而最佳的過彎防止翻覆方法是降低車行速度,提高轉彎半徑,增加路面外側傾斜度,以及提高汽車質量中心寬高比”四、汽車過彎不致翻覆的最大極限速度 Vc 以及最小轉彎半徑rc分別為 vc=〔 rg ( tan θ + K ?)/ ( l 一 K ? tanθ ) ]; rc =( V2 / g ) ( l 一 K?tanθ ) / ( tanθ + K? ) 五、本實驗所設計紅外線偵測變頻式可調迴轉模擬機,可有效的模擬汽車過彎翻覆,適用於中等學校物理、力學等學科的實驗課程。The accident of overturning a car always results in both destroying the car body and the death of the people. This project is to investigate what factors would have an effect on overturning a car and how to prevent a car from overturning.This project explores the factors by varying the mass of the cars, the distance between axes, the height of the car body, the ratio between the axis distance and the car height, the central gravity, and the declination. We test and record different overturning rotating speeds of eight model cars by a self-made adjustable simulator with a varying frequency infra-red detector. According to the experiment, the following results are obtained. I. The overturning occurrence is as a result of the eccentric force over the critical lateral force. The critical lateral force is F=mg(tanθ +K?)/(l—K?tan θ) 2. The square of allowable maximum speed is in proportion to the product of turning radius and ration of width to height for the center of mass; however, the allowable minimum turning radius is inversely proportional to the ration of width to height for the center of mass under constant vehicle speed. The above inference is independent of the mass of vehicle. 3. Increasing the declination can prevent a car from overturning. 4. The maximum speed for a car turning without overturning is Vc. The minimum turning radius is r. Both are expressed as follows:Vc=[rg(tanθ +K2)/(1—K?tanθ );rc=(’V2/g)( I —K?tanθ )/(tanθ +K?)5. The self-made adjustable simulator with a varying frequency infra-red detector can be used in the experiments of the middle school science curriculum.

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液滴在我眼前蒸發

本研究的目的在觀察液滴的蒸發過程,探討影響一滴蒸發方式改變的變因。我們利用數位攝影機外加近攝鏡頭,由側面逆光拍攝液滴蒸發過程,並轉錄成電子檔利用電腦協助分析。液滴影像分隔放大投影在方格紙上,以便測量接觸角及高度的變化。結果發現蒸發情形可分為三種:Ⅰ.當接觸角大於九十度時,液滴和界面的接觸線迅速外擴,直到接觸角遞減至90度後定住不動,蒸發終了時,接觸線迅速內縮,留下縮小的實心殘跡。Ⅱ. 當接觸角小於九十度時,接觸線先些微外擴迅速外擴,之後定住不動,直到蒸發終點,液體內縮,留下環狀殘跡。Ⅲ.當接觸角小等於九十度時,接觸線始終定住不變,液滴蒸發後留下原大小的實心班跡。液滴蒸發時接觸角和高度並不是連續變化,而是交互階梯式遞減。本研究的結果可應用在探討噴漆及噴墨印表機的噴墨印刷上。The objective of this investigation is to observe the evaporation of liquid drop and find out the factors that could affect it. A digital camera with micro lens is used to film the process of the evaporation. And a close-up of the sample drop is taken with backlight. The results are analyzed with a personal computer. The magnified images of the drops are projected on grid papers for measuring the changes on contact angles, and heights of drops. We classify the evaporation of a drop into three types: Ⅰ. The contact angle is greater than 90 degrees. At first, the contact line will spread outwardly till the contact angle decrease to the 90 degrees and then be pinned until the evaporation reach its terminal. At last the contact line quickly contract inwardly, and a solid stain remain. Ⅱ. The contact angle is less than 90 degrees. The contact line will spread slightly and then be pinned. At the terminal the liquid contract inward, and a ring-like stain is formed. Ⅲ. The contact angle is equal to 90 degrees. The contact line will always be pinned, and no ring, but spot stain is left. During the evaporation, we discover that the contact angle and the height of the drop do not change continuously but alternatively decrease by steps. The results of our investigation can be applied to the aspects of paint-spraying and jet printers.

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咖啡王子一號店~研製咖啡渣活性碳

在台灣飲料市場的佔有率中,咖啡飲料高居第四名,由此可見咖啡渣數量是非常驚人的。上學期我們在自然課中學到燃燒的相關知識,於是我們決定運用乾餾法,展開「咖啡渣活性碳」的研究!透過實驗與操作,我們研發出「咖啡渣活性碳的製作方法」,也驗證自己研製的「咖啡碳」和活性碳一樣,具有吸附雜質以達到淨水和脫色的功能,更設計出具有環保概念且能實際應用於生活中的相關物品。研究過程中我們花了很多時間討論、設計並操作,為了突破實驗器材的限制,我們也多次前往五金行找尋突破器材限制的改良方法與靈感。師長和同學們都說我們的研究看起來很辛苦,但是因為有許多成長與發現,因此就算再辛苦我們也覺得非常值得。

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研究傳統降火氣食品是否具有抗發炎效果

在炎炎夏日總希望來點可以「降火氣」的食品,依據古籍記載某些中藥材具有降火氣的效應,而中醫所謂的降火氣與西醫的抗發炎反應密切相關。本實驗利用巨噬細胞株受到LPS (Lipopolysaccharide,革蘭氏陰性菌細胞壁表面所含有的脂多醣體)刺激後,會分泌發炎介質的現象,再分別加入各項傳統認為可降火氣(以菊花、薏仁、仙草作為樣品)或上火氣(選用龍眼作為樣品)的中藥食材,來評估中藥材對巨噬細胞分泌發炎介質能力的影響。經由實驗,我們發現市售的『降火氣』中藥食材,在適當的濃度下,確實具有降低IL-6、TNF-α 分泌量的能力,但濃度過高時卻會造成細胞凋亡。另外,傳統以水熬煮的方式比冷凍乾燥取得的樣品有更好的降低IL-6、TNF-α 分泌量的能力。 我們期望以此一系列的實驗,來建立篩選『降火氣』食材的抗發炎效用的研究模式,並在後續實驗中可用以篩選出更多具抗發炎效應的中藥材。In summer, people always consider eating some special things to refresh themselves. According to ancient books, there are some Chinese herbal medicines that were recorded to have the function of cooling us down, which is related to anti-inflammation in the Western. Macrophage cell lines can be stimulated by LPS (Lipopolysaccharide) and secrete proinflammatory mediators. Thus, it is often used to evaluate the anti-inflammatory effects of different herbs. In our experiment, we also use macrophage cell lines to test different anti-inflammatory effects between chrysanthemum, Job’s tears and grass jelly. In addition, some Chinese herbs such as longan that can parch us are also tested in our experiment. In our results, we found these herbs that are available indeed have ability to anti-inflame in appropriate consistency; however, high dose does harm to cells. In addition, the samples that are poached in ancient ways have better ability to show the low dose of IL-6 and TNF-α. Finally, we would set up a model to test the anti-inflammatory ability of different herbs that were said to be able to cool us down, and then we could test more herbs in the future.

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直接乙醇燃料電池之觸媒層研究

直接乙醇燃料電池以酒精與氧氣透過氧化還原反應產生電能,但化學反應緩慢,需利用觸媒以增加其速率。本實驗目的在於盡可能找出一個表現最佳的觸媒。本實驗利用活性碳粉作為觸媒(鉑、錫)的載體,以酸性(HNO3)與鹼性(NaOH)環境分別處理碳粉,再以含浸法與多元醇含浸法將觸媒還原。我們得到以HNO3 處理的碳粉無法保有原碳粉的型態,較利用NaOH 處理為差。在觸媒製備方面,多元醇含浸法還原效果比含浸法可得到較小的觸媒尺寸,在本實驗中,溶液中鉑與加入的碳粉重量比為3:7 時,可得到最大的反應面積。此外,當鉑與錫原子數比為4:1 時,可得到最大的乙醇氧化電流。Direct ethanol fuel cell is a kind of power source which generates electrical power by a redox reaction involving ethanol fuel and oxygen. However, this reaction takes place slowly; therefore, catalyst is needed to improve its activity. The goal of this project is to get an optimize catalysts ratio to obtain the best catalyst activity. Activated carbon is used as the support of catalyst (platinum and tin) particles in this project, which is pre-treated in acid (HNO3) and alkaline (NaOH) solutions respectively. Then, the precursor is reduced by impregnation and EG-impregnation. We learned that activated carbon pre-treated with NaOH activates better than which pre-treated with HNO3 because the latter bear less resemblance than the former. As for the catalyst, the results of EG-impregnation show smaller size of catalyst particles than those of impregnation. In this project, when the ratio of the weight of platinum and activated carbon added into the solution is 3:7, we can get the largest surface area. In addition, when the ratio of the amount of platinum and tin atoms is 4:1, we can get the largest current of ethanol oxidation.

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蕨紋密碼-蕨類氣孔系之形態研究

蕨類植物葉面下表皮的表皮細胞形態以及氣孔系的形態有豐富多元的變化,比起其他類群植物,蕨類的氣孔偏小,幾乎呈線型,保衛細胞週遭幾乎都存在數目不等的副細胞,且其表皮細胞呈拼圖狀的波浪型。我們分析多種蕨類氣孔與周遭表皮細胞的形態關係,發現同科蕨類植物之氣孔系形態相似,可作為分類的依據;而不同科蕨類之間氣孔形態的關係與孢子囊親緣關係樹不甚符合,並依此繪出依氣孔系安排的親緣關係樹。而蕨類植物與其他類群植物的演化及形態關係則有待我們進一步研究。

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握在掌心的音樂—手笛

用雙手合攏當樂器,掌心空間當共鳴箱,用嘴吹氣在兩大拇指之間的空隙,吹出的聲音像笛音一般,這就是「手笛」。能吹出笛音跟嘴形無關,要成功的吹出笛音而不是氣音,須符合3個條件:1.吹孔空隙要小(<0.15公分);2.吹孔空隙兩旁要有彈性物質(兩大拇指的肉);3.要順著掌心空間切線位置吹氣。而我們也發現:1.掌指關節間愈寬,笛音愈低;2.掌心空間直圓周長愈長,笛音愈低;3.愈用力吹手笛,笛音愈高;4.吹孔寬不影響音高;5.掌根開洞愈大,笛音愈高;6.掌心空間愈大,開洞要更大才有明顯的音高變化;7.手指開洞會比掌根開洞影響手笛音高來的明顯;8.手笛開洞的位置會影響它的音高,距離氣流其始位置較近,影響音高較明顯。

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魚洗水跳現象的探討

In the previous year study, we assumed that the fish basin as a column-shape model in order to exam and explain how the water spouting. This year, we established a reality-like situation of the fish basin to construct our theory base. At this point, round-waves and up-down waves are found as the beginning point of the water spouting. The sound from the basin is the frequency of the vibrations. Meanwhile, this process enables us to understand the causes of four, six, and eight waves. In addition, we tried to change the basin's positions, the capacities of water, the densities of liquids, and the sizes of the containers to demonstrate the theory. Furthermore, we used similar containers, such as high-heel cup and big magnetic bowl to experiment. The results are also corresponded with the theory. These results can also be used to explain the Chinese aeolian bell, clock, shaking bell, etc. That is a major innovation for us. Finally, we obtain better understanding of the abstractive theory though the simulation of the computerized photographs. 魚洗,也稱龍洗,傳說是中國唐宋時代皇帝洗臉的臉盆,內底四條魚紋,麟尾畢具。洗內盛水後,用手摩擦其兩個雙耳,立即發出響亮的嗡鳴聲,並出現美麗了漣漪,水珠四濺,摩擦越快,聲音越響,波浪翻騰,水珠越烈。對此在上一年度的研究中,是將洗盆視為圓柱狀,然後由圓柱狀所建立的模型去解釋水跳的原因,初步瞭解了水跳的原因。今年我們以洗盆真實的情況建立理論模型,在殼體產生共振的圓形駐波及上下駐波,此為水跳產生點,此時殼體發出的聲音就是共振的頻率。也瞭解了有四個、六個、八個、十個波腹的原因。並以改變殼體不同位置、水量、液體密度及洗盆大小等變因應證模型,結果與理論相符合。繼而以高腳杯、大磁碗等類似魚洗盆構造的容器,加以實驗應證,也能符合此理論。甚可推到中國古時候的編鐘、搖鈴、風鈴等器材。對於我們總認為碰撞就產生聲音的觀念實是一大突破。最後經由電腦動畫的模擬,讓此抽象的理論更容易瞭解。

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東沙島海灘的變遷與復育:由龍擺尾停擺說起

政府最近公佈在東沙群島設立第一個國家海洋公園,顯示國人重視海洋資源的保育與復育;但是東沙島特殊的自然景觀「會擺動的沙嘴」—龍擺尾,卻因興建八座消波塊構築的突堤而消散停擺。本研究以一個高中生的觀點,設計及進行一系列的模型實驗,探討東沙島的形成機制、各種環境因素對海灘及龍擺尾的演化、驗證龍擺尾的現況及如何讓龍擺尾復活,再由東沙島海灘復育看世界的海岸問題。雖然設備很克難,但都能完成預定的目標,證實東沙島的海灘演化。希望此次對東沙島海灘的研究成果與初步探討,能應用於世界上遭受侵蝕而需復育的海岸。In 2007, our government proclaimed Dongsha archipelago as the first national marine park, signifying her emphasis on the conservation and restoration of marine resources. However, the sand spit on Dongsha island, a unique natural wonder commonly referred to as the “swaying dragon tail”, has become motionless since the construction of a total of eight groins along its SE and NE coast during the period between 1993 and 1996. This study has conducted a series of model experiments to verify several fundamental issues, ranging from the formation and the factors affecting the stability and the status quo of Dongsha island and its spit. The experimental results find several favorably outcomes, giving the coast evolving evidences of Dongsha island. Furthermore, strategy to stabilize the coast and revitalize the spit are then considered, which could hopefully benefit the coast suffering erosion on the world’s coastline.

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線上教學資源

追「風」逐「電」 -以風力發電機進行探究與實作

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摺紙成疊的探討

在教室的圖書箱有本數學遊戲書「茅塞頓開」老師偶而會拿裡面題目、和我們遊戲討論,其中有一題是「摺疊地圖」: 一張地圖的長為寬的兩倍。有很多種方法可以把它摺疊成一個面積為原來大小八分之一的正方形。按上圖的方式標示號碼,並記錄下摺疊好的地圖中數字出現的次序,看看你能找到多少種不同的摺法。 現在要考驗你的技巧,請把地圖摺好,使得數字順序為 l 、 2 、 3 、 4 、 5 、 6 、 7 、 8 。 其實這個遊戲和地圖一點關係都沒有,而是要摺紙,使它有次序的成一疊,數字由上到下 1 、 2 、 3 、 4 ……排好。基本上它的構造是正方形連塊但八連塊所有變化實在多,頭都昏了。於是我們試著加以改變再探討。

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渡河問題

有一農夫帶著一隻狼、一隻羊及一個高麗菜渡河,而農夫划著小舟,一次只能載一物件。當農夫不在場時,狼會吃掉羊,羊會吃掉菜。只有農夫在場時,才不會發生上述情形。討論其最小移動次數及方法總數。 將菜、羊、狼編號為1、2、3,規定2能吃掉1,3能吃掉2,食性距離為一。其移動次數為7,方法總數為2。再將物件總數增加至n,利用合法狀態、連線數得到移動次數為7,方法總數為。另外討論平均移動次數,以了解物件編號為奇數與偶數不同的移動情形。 當了解距離為一時的移動情況後,延伸至距離大於等於二時,最後分成三個種類來討論。分別為: (一)物件總數:n ? d+1: 走法總數:n2 - n 種走法 次數:3次 (二)物件總數n=(β(d+1)+1): 走法總數:-Y種走法 次數:5次 (三)物件總數n=(β(d+1)+R),其中(R?{2~d}: 走法總數:-Z種走法 次數:3次

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