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熱門關鍵字: the king 水果 豆漿 電腦
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光合細菌對水中污染油脂分解之探討

此研究是探討光合細菌對污染水中油脂的影響。利用光合細菌(Photosynthesis Bacteria; PSB)來探討對油脂分解的能力,實驗使用的油脂4種,分別是柴油、沙拉油、橄欖油和豬油4種油脂來做為實驗對象。然後取4種不同的油脂各2克分別加入光合菌液98公克做為實驗組,對照組則取4種不同的油脂各2克分別加入海水98公克作為空白對照(不另添加光合菌),每組皆為2重覆實驗,以純光合菌液98公克作為校正組,再利用索氏萃取裝置分離光合菌和水中的油脂,進行油脂回收,實驗進行4週,計算油脂的減少量和油脂分解率作為評估光合細菌對4種不同油脂分解的能力。

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「渦」藏「聖」機--以渦流脫離重新詮釋聖嬰發生的原因

If we place a block in continuous, steadily flowing water, some periodic eddy currents will appear behind it. In my report, I would like to introduce a new way to explain how the periodical movement of eddy currents would help to triggering El Nino. According to my experiment, these eddy currents have a certain life cycle, and the eddy current give a force, which drag water form the area they just went by. It will cause water level became lowest for a period of time. These phenomena are also shown in the real data of “Sea Surface Height Anomaly”, it is a quiescence period, and then changes into the highest one it is interesting that highest one always follows by the starting of El Nino. Another important result from my experiment is that, in the same fluid, the frequency of eddy currents is controlled by 2 variables: Size of the block and velocity of the flow, From this result, then get the frequency of eddy current-occur every 3.2 years. It is just correspond with frequency of historical data the El Nino from the 70’s to the present. 本報告嘗試以南極繞極環流在南美洲南端產生週期性渦流脫離的現象來解釋聖嬰的發生根據水槽實驗的結果,水流在通過障礙物後渦流脫離瞬間,會形成一水位低的空區,之後在周圍的水大量湧入,水位突然升高,並有一段時間的振盪。另外,實驗結果也顯示,渦流形成和脫離頻率大致上和注水流速成正比,且和障礙物的大小成反比。根據此結果,對照實驗結果,我認為1993 年3-4 月,1996 年1-6 月及2001 年7-10 月三個「海平面高度異常」的最低值密集帶,此極可能是渦流脫離的時段。且對照「海平面高度異常」實際資料後,發現「海平面高度異常」的「最低值密集帶」後均伴隨水面「寧靜期」,接著就出現周圍暖水流大量湧入的「最高值密集帶」,此時南美洲東南側海水溫度驟增,接著馬上接續著聖嬰的到來。「海平面高度異常」分析的結果,指示渦流脫離的「最低值密集帶」和顯示著聖嬰到來的「最高密值密集帶」間約間隔半年左右。我們推算水的史托爾數約為1,以這個值代入實際南極繞極環流通過南美洲南端,得到渦流脫離的頻率約每3.2 年一次,和長期聖嬰發生的平均頻率非常接近。

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遠離“干擾”與 “飄浮”─汽車擾流板之探討

學校的停車場停了十幾輛的轎車,其中有幾輛轎車的後車廂蓋上多裝上一片顏色和車子一樣的橫桿,我覺得很奇怪,請教老師,老師說這個東西叫做擾流板,它可以減少氣流對行駛中的車尾的干擾力量,也可以使行駛中的車子更為下沈,我聽了以後滿腹的疑問:流經車體的氣流怎會對車尾有干擾的力量呢?擾流板真能減少干擾的力量嗎?還有擾流板真能使行駛中的車體更下沈嗎?如果可以,那麼,怎樣安排方式的擾流板,才是最有效果呢?多寬?多高?什麼角度?什麼位置最恰當呢?為解決這些疑問,我們在老師的指導下,做了這一個研究。

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鹽水真能有效洗去蔬果表面殘留的農藥?

用鹽洗菜是否有效呢?我們這次實驗所使用的方法為生化(酵素)快速檢驗農藥殘留法,針對加保力、納乃得農藥,利用乙醯膽鹼酯?經過反覆數次的檢驗,從實驗數據中我們發現使用鹽洗菜的方法並不一定較有效,我們的最終結論是:用鹽水來洗菜比用一般清水洗的效果還要差,反而會使農藥因溶解度下降而更殘留在蔬菜表面。針對最近有許多的家庭主婦已經習慣用鹽水洗菜,卻不知反而造成更多農藥的殘留,所以我們建議大家在洗菜時,最好只用清水沖洗,不要再加入鹽巴,因為這個步驟將是多餘且有害的。

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n x n 方格表中的計數問題

對4 × 4 方格表中計數問題的二個解題方法(1..解方程式的方法, 2.分割圖形的方法)作分析和研究後,首先我推廣分割圖形的方法來証明 : “好的n × n 方格表” 存在若且惟若n 為偶數。同時証明這種“好的n × n 方格表”內所有n2 個數的總和f(n) 為n(n+2)/4。當討論一般的n×m 方格表時,發現分割圖形的方法盲點,無法繼續推廣來証明。再經過深入分析與推廣解方程式的方法,藉由n×m 變數方格表,我們終於找到構造所有“好的n × m方格表”的方法。同時計算“好的n × m 方格表” (n≦m)內所有mn 個數的總和f(n,m), n≦7和証明好的nxm 方格表會有2(n+1)行一個循環的現象。We first studied two solution methods (1.solving equations,2.dissecting diagrams.) for calculations on 4x4 checkboard. Using the method of dissecting diagrams, we proved that``good nxn checkboard'' exists if and only if n is even. Furthermore, the sum f(n) of those n2 numbers in a ``good'' nxn checkboard is equal to n(n+2)/4.In studying the more general nx m checkboards, we found that the method of dissecting diagrams does not work, However, by extending the method of solving equations, and by considering nx m variable checkboards, we obtained a way of obtaining all ``good nxm checkboards.'' By way of computing the sum f(n,m) (n≦7) of those mn numbers in a ``good nxm checkboards,'' periodicity in every 2(n+1) rows is observed.

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向左走向右走~相鄰移位遊戲最佳策略探討之研究

本研究為傳統遊戲創新,改變遊戲形式與玩法,中間前後不留空格,且題目中花色種類按a、b、c……順序排列,在每種花色數量相等的情況下進行直線相鄰移位遊戲。研究裡設定了三種不同的最後排列順序要求,觀察當花色種類數與每種花色數量為任意數時的最少移位次數,試著從操作過程歸納最少移位次數(最佳解決策略)之規律,並得到通式。接著,將直線型改為其他排列圖形─順時鐘環形,同樣的歸納在最後三種不同排列順序要求下最少移位次數之規律,得到通式,並比較與直線排列之相關性。

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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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氯化亞鈷錯離子在若干醇類中顏色的變化

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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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A Study For Heavy Metals Detection Using The Solubility change of Different Kinds Solute

A research on how a solution mixed with two or more solutes affect the solubility of each solute was done. If different solutes are put in a solution with a specific concentration, the solubility of the single state solute increases, stays the same, or decreases. The difference in solubility caused by several solutes will give solutions on selectively collecting heavy metals from bodies of water polluted by these heavy metals even more effectively. To test the changes in the solubility of the solution with several solutes, sedimentation has been used; however, colorimetric analysis was also done to observe the changes in color of solutes that show color in the solution. Nitrate compounds of Sodium, Magnesium, Strontium and Potassium were used for the typical metals, and for the transition metals, nitrate compounds of Silver, Cadmium and Lead were used. Test results show that Sodium decreased the solubility of Lead, and as the concentration of Sodium increased, the solubility of Lead increased too. On the other hand, K increased the solubility of Pb, and as the concentration of K increased, the solubility of Pb decreased. We can use the radius of ions and the enthalpy of hydration to explain the changes in solubility. In the case of Cd, as the concentration of K, Mg and Sr increase, the solubility of Cd increased with it. This is because the difference between the ionic radii of Cd and the other ions (K, Mg, Sr) has a tendency to increase in solubility in the enthalpy of hydration. Also, as the concentration of Ca increased, there was a tendency in which the solubility of Cd decreased. This is because the ionic radii of Cd and Ca are similar to each other and there was a tendency that the solubility decreased in the enthalpy of hydration. Through this experiment, the study shows the tendency of the change in solubility of several solutes by comparing ionic radius and the enthalpy of hydration, and if this result is used, the processing of certain heavy metals in the bodies of water can be even more effectively used than the previous method.

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線上教學資源

石化石說玩化石

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哎喲!橡皮筋又斷了!為什麼

彈橡皮筋一直是我最喜歡的遊戲,玩的方法多,攜帶又方便,可是玩過一陣子後,橡皮筋會變得很容易斷裂或橡皮表面像被風乾的裂痕,尤其寒冬酷夏這情形更明顯。於是在好奇心驅使下我請教了自然科學考師,並在老師指導下,我們進行一了下列的實驗。

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