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依據拉午耳定律,在稀薄溶液的條件下,其熔點下降溫度△T恆與溶質之重量莫耳濃度Cm成正比,亦即△T=KfCm,Kf被定義為莫耳熔點下降常數。又前人實驗出,純水熔點亦會因侷限在孔洞中而下降,稱超冷水。探討論文後發現熔點下降量與孔徑有之關係,我們便思考水溶液在空間侷限下是否也會有類似現象?於是我們將不同濃度的葡萄糖水溶液置於孔洞中測量其熔點。實驗發現葡萄糖水溶液在固定的孔洞中,熔點亦隨溶質之莫耳濃度上升而下降,符合拉午耳定律。改變孔徑的大小,進一步發現莫耳熔點下降常數k會隨著孔徑縮小而增大。顯然水溶液的熔點可同時受到空間侷限與溶質的莫耳濃度所影響,因此加入葡萄糖後,水溶液除遵循拉午耳定律的影響外,又使其熔點進一步下降。如何將拉午耳定律從單純的溶質的莫耳濃度函數,推導含蓋侷限空間R因子的通一公式,亦即更廣義的拉午耳定律:△T=k(R)×Cm是本計劃的主要目標。
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科展作品檢索
為什麼切過的番石榴會變黑?為什麼不成熟的番石榴會有澀味?
一天中午,在學校吃過午飯,我拿出媽媽給我準備好的水果(番石榴)來吃,我想一個人吃不好意思,於是拿出削鉛筆的刀子洗乾淨,把番石榴切開,分給幾個同學吃,妻好後才發現它的切面有噁心的黑色變化,我們都不敢吃,不知道那是不是有毒,於是請教老師,為什麼切開的番石榴會變黑?可不可以吃?老師就指導我們做一連串番石榴變嘿,以及未成熟時含有澀味的實驗。
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我們上次參加台北市第二十二屆中小學科學展覽會,很榮幸,獲得了優等。在會場裡,我們看到大家版面上貼的書面紙,有各種顏色,五彩繽紛,十分耀眼。我們聯想到現在的工商業社會,紙的需求量很大,大量的砍伐樹木,廢紙愈積愈多。我們想,能不能把廢紙回收,重新製造成有用的紙,而不造成污染又節省資源呢?於是,我們幾位同學,請教了老師,做了以下的實驗。
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Motivated by Napoleon theorem, we study the properties of the triangles obtained by moving the midpoint of each side of a given trianle along the perpendicular bisector of corresponding sides, and extend the results to the case of quadrilaterals. On the other hand ,we consider the method of erecting a regular M-gon to each side of a given N-gon and joint the N centers of these M-gons to form a new N-gon. (abbreviated as CRG method),and get the following results. 1. We characterize some kinds of N-gons that can be transformed to regular N-gons via CRG method. 2. Of M,N are nature numbers with M|N, then it is possible to find a N-gon that can be transformed to a regular N-gon by CRG method. \r 3. If a polygon P is symmetric with respect to a fixed point or a fixed line, then P can be transformed by CRG to a polygon with similar symmetries. 4. If a polygon P is transformed by CRG to ′P,there exists a commonpoint G such that ΣGA=0 andΣGB=0, where A and B runs through vertices of and P′P, respectively. 本研究將拿破崙定理加以延伸。先探討由各邊中點沿中垂線延伸得出之三角形的性質並推廣至四邊形之情形條列式報告成果。另一個推廣是將給定的多邊形的每邊外接一個正多邊形,再以這些外接的正多邊形的中心為頂點造出一個新的多邊形。我們發現此幾何變換具有以下性質:(1) 「哪些多邊形能被變換成正多邊形呢?」,我們觀察出能被變換成正多邊形的多邊形其限制條件隨邊數增加而增多,並進一步區分了哪些多邊形可以被變換成正多邊形。 (2) 在將非正N邊形做變換時,不一定須外接正N邊形才能得到正N邊形,我們區分出可外接哪些正多邊形而得到正多邊形。 (3) 對給定的多邊形作此變換時,若原多邊形有點對稱或線對稱等性質,則新多邊形也將具有相同的性質。 (4) 此變換得到的新多邊形會與原多邊形共重心,亦即新舊兩多邊形內到各自的頂點向量和為0的點會是同一點。
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藉由大家的提問及討論還有腦力激盪,找出「魔術數學骰子」遊戲背後所隱藏的數學規則,並設計出我們自制的「魔術數學骰子」。
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科展作品檢索
線蟲補捉菌Arthrobotrys musiformis 黏液相關基因之選殖與功能界定
線蟲捕捉菌Arthrobotrys musiformis 是一種可經線蟲誘導產生捕捉網來捕捉線蟲的真菌,本實驗即針對A. musiformis 的捕捉網黏液相關基因:Manosyltransferase(AH73), β-1,3-glucan transferase(AH102), fimbrin(AH121)及mannose-specific lectin precursor(AH338)進行選殖與功能界定,希望建立這方面的研究基礎,將來能應用在松材線蟲的生物防治上。首先我們大量培養A. musiformis,萃取菌絲體的DNA;接著進行聚合?連鎖反應 (Polymerase Chain Reaction,PCR) ,利用專一性引子對 (primer) 大量增幅AH73、AH102、AH121 及AH338之基因片段;增幅後的產物經過純化、選殖,定序並進行分析比對,確認增幅之序列無誤後,以 Digoxigenin (DIG) 標示當為探針,篩檢A. musiformis 的Fosmid Library﹔目前已成功選殖出AH73 之可能基因,完成AH73 之探針製備,並以其篩檢A. musiformis 的Fosmid Library﹔呈雜合正反應之選殖株 (clones) 將以散彈槍方法(shotgun)定序,作序列組合,探索相關的基因;接下來用 Rapid Amplification of cDNA Ends(RACE) 做出互補DNA (complementary DNA , cDNA) 全長度後;最後建構基因缺失株,驗證此基因所調控的生理以及生化機能。 Nematode trapping fungus Arthrobotrys musiformis can capture nematodes by producing adhesive nets when nematodes go through. Many kinds of nematodes, including pine wood nematode (Bursaphelencus xylophilus), can be captured. Pine wood nematode causes serious pine wood disease. Therefore, A. musiformis has the potential of biocontrol in pine wood nematode. Our research focused on adhesion and adhesive relevant genes of A. musiformis :Manosyltransferase (AH73), β-1,3-glucan transferase (AH102), fimbrin (AH121), and mannose-specific lectin precursor (AH338). We try to clone these genes and carry out functional analysis. In order to achieve this goal, we used specific primers derived from previously obtained complementary DNA (cDNA), by Polymerase Chain Reaction (PCR) to amplify these genes and gained adequate quantity of genomic DNA products. After sequencing and verifying of the identity of the genomic DNA, we use Digoxigenin (DIG) to label them and use them as probes to screen the constructed A. musiformis Fosmid Library. Currently, the Southern colony hybridization is undergoing. The positive Fosmid clones against the specific probes will be sequenced completely by shotgun library to monitor the existence of adhesion related gene cluster. After working out the full length cDNA of these genes, we will use them to construct replacement vectors to knockout the adhesion related genes, creating mutants and further verify their functions through genotype or phenotype bioassay.
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本研究藉由浴室滑倒的例子,結合國小課程「摩擦力」與文獻資料,探討浴室地板、室內鞋和水溶液等三大因素,並交叉組合測量摩擦係數大小,試圖找出最防滑的搭配。研究發現乾燥的環境最為安全,潮溼環境和平滑的浴室地板都比較危險,尤其在佈滿潤髮乳的地板和含水溶液的光亮磁磚地板上,室內鞋的防滑效果有限,不能過度依賴。我們有以下建議:一、浴室採用乾溼分離設計,以減少溼滑的地板面積;二、使用水溶液將增加滑倒風險,使用完畢應沖水潔淨並擦乾地板;三、浴室地板應該使用具有凹凸不平的防滑磁磚;四、慎選浴室防滑拖鞋的種類,以塑膠硬底鞋的防滑效果最佳,紙質室內鞋容易滑倒,需要特別小心,並且不要過度依賴廠商宣稱的浴室拖鞋防滑效果。
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科技始終來自於人性,本作品是以綠能驅動農業環境之改造及生物、光電科技等的結合同時亦具節能減碳、多彩照明、有機土壤改良、物理性蟲害防治與光色舒療法等綠活之效果,並藉由科技與自然環境之媒合而深植於普羅大眾生活之中,進而達到有機農業推廣的目的。其作品特色: (一)、響應節能減碳有助減緩地球暖化現象。 (二)、多變色捕蟲燈的特有光源引誘有害之昆蟲,有效捕殺,且多彩夜間自動照明亦增加捕捉各類害蟲之機會。 (三)、隨季節溫控變色浪漫多彩照明效果能舒緩心情、健康樂活。 (四)、針對無法吸引之昆蟲或特定作物之專屬蟲害,則使用其昆蟲費洛蒙全方位誘殺,使捕蟲器更趨近於完美。 (五)、太陽能驅動有機肥料(含枯枝、落葉、雜草、蟲類遺骸等有機質)分解之、以利土壤改造使土壤達永續經營之效。
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灰色理論近來廣泛應用於各行各業的管理資訊科學上,本研究乃應用灰色理論的一階微分中輸入變數為一項之 GM ( 1 , 1 )模型,來預測台灣中部地區土石流主要因素雨量的月平均量值。本文運用三筆以上的歷史資料,作最近一年歷史性資料的預測,藉以驗證獲得其誤差(±△e)之校止參考依據值,比利用殘差檢驗所得的誤差校止數據,更能修止出精確的預測值,接著再做台灣中部雨量未來之預測,以作為未來雨水、土石流防治之參考 · 為了能迅速產生所要的灰色預測值,研究中並以 VB 程式語言及以Petri-net分析其動態處理行為,藉 GM ( 1 , 1 )模型的專屬處理支援程式,以做為未來雨輦自動化處理警示與預測之支援機制。Recently Grey Theory has been widely applied to management information science in all kinds of areas. This research applies the first Level differential of the Grey Theory to put a variable in GM( 1,1) model to forecast the monthly average value of the most common precipitation, in the midland Taiwan earth-stone flood zone. This paper uses more than three historical data to forecast the most recent year’s historical data, which can be used to verify and acquire referential correction data of its errors ( ±△e). The aforementioned method can correct forecast data more precisely than the differential inspection. In addition, this method can then forecast future precipitation in midland Taiwan earth-stone flood zone and the results can serve as reference for future precipitation control. To rapidly receive the needed Grey forecast values, the research analyzes its dynamic process method by utilizing VB program and Petri-net to build a dedicated process-support program of GM( I , 1) model. This program will serve as a support mechanism for future automatic precipitation warning and forecast.
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投石器是古代的攻城利器,要打破堅固的城牆,沒有它可是困難重重。但是投石器可不是胡亂投,用亂石打鳥的方式來攻擊的,砲彈的落點是可以計算出來的。投石器的結構主要區分為底座與投射桿兩個部份,投射桿又可區分為投射端(抗力點)、支點、重物端(施力點)三個部份。影響投石器投射距離的因素有:抗力臂的長度、施力大小、砲彈重量。1、抗力臂長度愈長,投射距離愈遠。2、施力愈大,投射距離愈遠。3、砲彈重量愈重,投射距離愈近。投石器要投得準,施力的構造必須要很穩定,每次的施力大小、方向都要一樣,所以施力的重物最好能集中成一組,較好控制力量大小。做為施力用的重物,必須要能夠擺動,利用由高處落下的重力以及到最低點時甩動的力量,把砲彈甩出去,如果重物與投射桿固定連接在一起,由於缺乏甩動的力量,是投不遠的。
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In this paper, we use telephone network to remote-control household appliances and monitor security system through the implementation of software and hardware. The purpose of developing this system is to build up a system that makes everyone take advantage of the telephones through pay phone network everywhere as and when he needs to set up the household appliances, meanwhile two-ways system of monitoring household security. In addition, due to the advances of communication technology and the remarkable boom of those products, the popularity of cell phones for local people is developing tremendously. We can link the portable cell phones up to the household appliances and monitoring household security through the offer network of communication companies. This system adopts public telephone network via multiple frequency to receive KT31 70 IC which is connected to EM78P45 i p Chip. And then the Chip is connected to the driving external circuit in order to control electric appliances, sensors on doors and windows. The utilization of LEPROM (93C66) memory to set up telephone and mobile phones number equips the telephone network with two-ways system of remote-controlling electric appliances and monitoring household security. In the part of controlling electric appliances, a monitor is used to display the status of electric appliances, to control the appliance switches and to set up the timer. In the part of monitoring household security, we use the system to receive the instant images of the house and to report on the closing or opening of doors and windows. The system will be informed on any occurrence of abnormalities. The memory of the system can record and update new data at any time and is able to set up twenty sets of telephone and mobile phone numbers. Besides, the system adopts identification codes to avoid malfunctioning and thus upgrade system reliability.本文旨在應用電話網路作遠端遙控家用電器及防盜保全歟控系統軟硬體之規劃與設計 。本系統研製的目的,是希望建立一套系統,讓每個人不管身置何處,都能利用電話透過公眾電話網路,輕易地控制家中的電器設備及進行環境設定,以達到控制家電及防盜保全之雙向監控系統。此外,由於通訊的進步與通訊產品的熱賣,使國月雍有手機的普遍性相當高,若能透過隨身攜帶的手機,經由通訊業者所提供的網路通訊管道,連結到家庭自動化與防盜保全系統亦可達到進行遠端遙控的目的,彌補出門在外無法使用室內電話的空檔。本系統利用公眾電話網路經複頻接收 IC ( KT3 170 )連接至單晶片( EM78P45 IP ) ,透過單晶片驅動外部電路與家中電器及門窗的監視感測器連接,再利用 EEPROM ( 93C66 )記憶體設定電話及手機號碼,藉由電話網路傳輸,以達到控制家電及防盜保全之雙向監控系統。在家電控制部份,採用顯示器可隨時瞭解家電使用狀況及控制其開啟或關閉,且可設定使用時問。在防盜保全部份,可隨時監控家中門窗,若有異狀可即時通告。記憶體可隨時記錄或更新資料,並可設定二十組電話及手機號碼。此外,本系統採用確認碼設定,可防止產生誤動作,系統可靠性高。
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所謂消毒細菌(殺菌)是利用高溫或化學品消滅所有的微生物,以達到沒有任何真菌、細菌及病毒的狀態。在紫外線的照射之下可將物體上的病毒、細菌等致病體進行物理的破壞,使其無法複製繁殖,達到完全徹底的消毒目的。雖然細菌的生存能力很強,即使在不利於其他生物生存的環境下,細菌還是能夠存活於其中。但強酸會破壞細菌導致死亡,也可達消滅細菌的目的。
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