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線上教學資源

動感自然課—體感式學習融入自然科教學

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「蟑」冠「裡」戴—蟑螂免疫系統之敵我辨識與記憶性等性質的探討

本研究建立蟑螂(Periplaneta Americana)之包囊作用(encapsulation)的觀察與測量方法,探討二氧化碳麻醉、植入物表面蛋白分子結構、可逆性與性別等因子,對免疫反應程度的效應,並研究敵我辨識與免疫的記憶性等特性。我們發現當異體的觸角被植入時,蟑螂體內所產生的包囊作用較自體觸角強烈,顯示具有辨識敵我的能力,且不同的生物性與非生物性植入物,所引發之包囊作用的反應程度亦不同。若分別先植入少量自體或異體組織,三日後再比較自體與異體觸角所引發的包囊作用程度,發現自體與異體組織的記憶效應不盡相同,我們證實蟑螂不但具免疫記憶性,且記憶性質具有促進性與抑制性兩種。另外我們也發現,雌蟲的免疫反應會大於雄蟲。

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一種排列的探討

這是換位子引起的問題。有一次,老師想讓每位同學都有同鄰而坐的機會且要在換最少次數內達成這個目的?這引發了我們的深思。 在最完美的狀態是每一次換位子都使每位同學與上次相鄰而坐的同學不再相鄰,且在最少次數下達成目的。由於面的討論複雜且一直無汰突破,只好先考慮線型排列的換位。問題是這樣的: 設從 1 到 x 個自然數原先排列為 1 , 2 , 3 , 4 ,……, n - 1 , n , n 十 1 , …… , x ,今將這 x 個自然數重新排列得 P1 , P2, …… , Pn-1, Pn, Pn+1, …… , Px,但任二相鄰數不得連號,(即滿足 Pi ± l ≠ Pi+1 , l ≦ i ≦ x - l ) ,這樣的換法有多少種?

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米飯的研究

是這樣開始的:有一段時期我煮的乾飯,不是沒熟便是太硬,我仍然事照以前一樣,一杯米加一杯水下鍋呀!奇怪!

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Extreme Mouse Mobile

Objective To design build and run 5 Mouse mobiles – vehicles which use mousetraps as their only source of energy. Targets- • Go up a ramp • Raise a flag • Hit something and set it free • Deliver something • Catapult Details These mouse mobiles are original creations which include some commercially produced parts. They are powered by single spring driven standard wooden mousetraps. They are 5 in number each being used for the respective tasks. Basic structure Each mousetrap consists of a 2 parallel wooden planks which has 2 holes drilled on either sides for the rear and front axles. A rod is used as the axle and CD disks are used as wheels. The mousetrap is attached to the planks. Movement and Locomotion To move the mouse mobile a string is connected to the rear axle. The string runs through 2 pulleys which change the direction of the applied force and are attached to the hammer of the spring. When the vehicle is pulled backwards on the floor tension is created in the string (as the hammer is stretched) which gets stored in the form of spring energy. When the wheels are released on the floor the rear axle starts rotating hence propelling the mouse mobile forward. Completion of objectives 1) To go up a ramp For the required task a high amount of torque would be needed .That will be sufficiently provided by the spring energy. 2) Raise a flag For the required task a rod is placed on the wooden platform. The flag is placed at the bottom of the rod; it is connected to the hammer of the mousetrap using a string. The spring and the rod are placed in the opposite directions. When the hammer is released after being stretched it pulls the string and raises the flag. 3) Deliver something For the required task 2 mouse mobiles are used. A platform of any hard and light material is attached to the rear of a mouse mobile. After reaching the desired location, when the hammer of the primary spring is fully relaxed it hits the catch of another stationary mouse mobile. The hammer of the respective catch is connected to the platform using a string. Upon activation the hammer is released, the platform is pulled with extremely high speed and the materials on the platform, due to their moment of inertia fall down. 4) Hit something and set it free. For the required task 2 mouse mobiles are used. A small mousetrap is attached to the front of the mouse mobile which is in contact to the required object. The other mouse mobile on reaching the above vehicle hits its catch using its hammer. The hammer of the stationary mouse mobile is released and the object is hit and set free. 5) Catapult For the required task 2 mouse mobiles are used. A mousetrap is attached to the front of stationary mouse mobile which is attached to a strainer and the object to be catapulted is placed inside it .Another mouse mobile approaches is and hits the catch hence activating the hammer and the object is catapulted.

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礁澳仁深-不同的水對麵包香氣及微生物生長之影響

本研究在探討不同的水處理酵母菌後,對製備麵包品質之影響,結果顯示利用28.5℃,濕度75﹪的發酵箱中進行發黴試驗,含鹽量較高的海洋深層水有延緩黴菌生長速度,但無法抑制其生長。另製成之麵包經物性測定儀及GC檢測後,17﹪海洋深層水中礦物質含量較高對酵母菌的生長有影響,在彈性表現最不佳,對麵包製作較為不利。稀釋海洋深層水5.6具有最佳的彈性、香氣、軟硬度、嗜好性及官能品評最佳,第二是蘇澳冷泉水,第三是仁澤溫泉水。食品中毒菌試驗部分,發現海洋深層水對大腸桿菌(Escherichia coli)、金黃色葡萄球菌(Staphylococcus aureus)與腸炎弧菌(Vibrio paraheamolyticus)三種食物中毒菌都有抑制或降低生長速率情形,仁澤溫泉水對大腸桿菌(E.coli)及金黃色葡萄球菌(S. aureus)都有抑制的效果。

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小而省的高效率鋅銅電池

課本中關於鋅銅電池的實驗其裝置複雜而且效果不佳,電流過小(約2mA),我們嘗試改良鋅銅電池的裝置予以縮小簡單化、增大電流,使電池足以讓LED 燈泡發光,增進實驗效果並減少藥品的浪費,並利用隨手可得的器材來製作各種小型鋅銅電池,最後發展出密閉不漏可隨身攜帶的鋅銅電池。

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宇宙演化的黑手

We study the effect of dark energy on the evolution of cosmic structure in a scenario where the dark energy is treated as free particles and thus can be localized. By theoretical derivation and numerical simulations, we found that: 1. The dark energy particles gain kinetic energy from a moving dark matter particle through gravitational interaction. Due to energy conservation, the dark matter particle will slow down with time Ek(t) = Ek0 - 9 × 10-5[|1+3w|ρDE]1.92t where Ek(t) is the kinetic energy of the dark matter particle,Ek0 is its initial kinetic energy, w is the coefficient of equation of state for dark energy, ρDE is the mean energy density of dark energy, and t is the time. 2. The formation history and structure of galaxy clusters are different in the presence of localized dark energy. The more the localized dark energy, the earlier the formation of the cluster core. In addition, the kinetic energy Ek(R) as a function of R will be different if the ρDE is different. Thus we can compare the observed Ek(R) of clusters with our results to deduce the ρDE in our universe. The results here can be applied to the observations in the near future. 我們探討宇宙結構演化受到可局部叢集之黑暗能量粒子的影響。藉由理論推導及電腦模擬,我們發現: 一、黑暗能量粒子會透過重力交互作而從運動中的黑暗物質粒子獲得力學能。因力學能守恆,黑暗物質粒子的速率會減慢,滿足 Ek(t) = Ek0 - 9 × 10-5[|1+3w|ρDE]1.92t 其中Ek(t) 為黑暗物質粒子的動能,Ek0 為其初始動能,w 為狀態方程式係數,ρDE 為黑暗能量的平均密度,t 為時間。 二、星系團的形成過程及結構,會因可局部叢集之黑暗能量的存在而改變。黑暗能量越多時,星系團的核心會越早形成。而且動能 Ek(R) 隨著至星系中心距離R 的變化,會因 ρDE 的不同而不同,因此可以將量測到的 Ek(R) 和這裡的結果比對,推導出宇宙中的 ρDE 。 這些研究成果將可直接應用在未來的觀測結果上。

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「藻」到「膠」點--探討海藻膠安定性與應用性之研究

石花菜乾料復水性佳,膠質量多,且可反覆抽取,產值高。以平板加熱器煮沸再持續加熱60分鐘後,其黏度可比原來增加五倍以上。且以抽取比例1:25,可達最佳的產值。在常溫做海藻原液觀察石花菜膠的安定性最好。經過50℃烘乾16小時後,可得到易保存乾燥的海藻面膜,經40℃復水5分鐘後,即可形成海藻凍膜,敷在皮膚上5分鐘後,其保水度迅速可從30%提升至45%。由圖表可知,石花凝膠(配方D)於敷凝膠第五分鐘保濕力高於仿市售蘆薈凝膠(配方E),而兩者皆有相同的保濕持久性。將石花凍直接裁切0.5公分厚度烘乾4小時,要使用前復水1分鐘,即可成為容易保存、製作成本低、膠強度好、可至少維持7小時的內膜傷口敷料,是個極具開發潛力的敷料原料。

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衣服是怎麼乾的?

筆者有一次,觀察洗衣機洗完、脫水後,在衣架上陰乾的衣服,發現衣服上端先乾且感覺較熱,雖然這好像是理所當然的事,但筆者認為生物課本上所說的毛細作用,應該可以讓水上升,為何一定要上端先乾?後來冬天到了,媽媽洗厚重的衣服,在最後洗清時,都有加柔軟精(如毛寶之類),筆者卻發現衣服上下幾乎是同時乾的。另外,筆者從氣象方面的書籍得知,空氣的密度會影響氣流的升降,那為何衣服下端後乾?是否跟水蒸氣含量及氣流有關,故決定著手去調查衣服是如何乾的。

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數學與遊戲

張鎮華教授在文章[4]中介紹威氏遊戲(Wythott’s Game):文章中提到安全殘局所成的集合Sw為 {(1,2),(3,5),(4,7),(6,10),(8,13),(9,15),(11,18),(12,20),(14,23),(16,26),…}。將這個集合中元素第一個座標的數所成的集合命名為A,而將第二個座標的數所成的集合命名為B,設其為A={a1, a2, a3,…}, B={b1, b2, b3, …}, 可以發現集合A和B滿足性質(1) A∪B=N ; 性質(2) A∩B=ψ;性質(3)數列是等差數列 ( bk- ak, k=1, 2, 3,…)。在這個研究計劃中,可以分成數學與遊戲兩部份:(一)數學部份:我們從不同的角度來介紹下列四個集合,並證明它們都相等。1.令{αs |集合S(αs )T(αs )= N?S(α)={[k(αs + s)] | k =1,2,3,…}滿足性質(1), (2), (3)},其中S(αs)={[kαs ] | k =1,2,3,…},T(αs ) = N?S(α)={[k(αs + s)] | k =1,2,3,…}。2.{αs | ([kαs ] ?[(k ?1)αs ] = 2 k=1+ (s ?1)n + [nα]), s=1,2,3,…}。3.{αs | 1/αs +1/(αs + s) = 1, s = 1,2,3,...}。4.{(2- s+√S2+ 4) / 2 | s = 1,2,3,...}。(二)遊戲部份:研究變型(第二型)威氏遊戲和推廣的三排威氏遊戲,利用我們學會的方法來找及證明這兩個遊戲的所有有利位置。下列三個集合都相等,同時它們都和上面的集合有密切的關係5.{X | X ?1/ X = [X ]}。6.{Xs | Xs- 1/Xs= s, s= 1,2,3,...}。7.{(s+√s2+ 4) / 2 | s = 1,2,3,...}。

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黏土材料之抗拉強度之韌性研究

本研究主要是利用黏土添加氧化鋅、氧化鈦,製成抗拉模型試體,置於室內乾燥,待乾燥後放入高溫爐中加熱,以高溫 1300℃鍛燒 9 小時,並於爐中冷卻到常溫。將試驗所得到的數據帶入建材吸水率、比重及抗拉強度等公式中,並分析試驗結果。由研究可知,添加不同的氧化物,所得到的比重、吸水率及抗拉強度皆不一樣,與未添加任何氧化物的純黏土比較,添加氧化鈦可提高抗拉強度,但添加氧化鋅卻降低抗拉強度。

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