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構想利用身邊可以回收的資源,設計一台可以製造歡笑,帶給周圍朋友幸福的「歡樂環保泡泡機」,經過同學們鍥而不捨的觀察討論,從泡泡水配方的研發、泡泡機結構的設計、吹出泡泡所需風力的探討、設計自動供給泡泡水裝置,到全自動感應式泡泡機的誕生,終於成功研發出泡泡機完整系統。由實驗探討發現,可掌握下列幾個原則:一、泡泡水最佳配方:RO水:洗碗精:甘油= 16:4:3。二、吹泡泡的風速大約3.5m/s 到 7m/s 較為適合。三、泡泡圈的轉速要慢,且轉的方向與風扇的轉向相反較佳。四、發泡圈的設計需要能夠多吸附些泡泡水,如增加溝槽或吸水材質等。
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上數學課的時候,老師教我們如何計算體積和容積。為了加深學習的印象,同學們利用下課的時候,計算各式各樣文具及簿本的體積,並利用上完課的大字報,摺出各式各樣大小的紙盒,來貯存各式各樣的文具及簿本。但是經過幾天的觀察後,卻發現這些紙盒並不實用,不但不方便攜帶,而且也很容易破損。正當大家陷入沉思的時候,突然有同學發現,佈告欄上的林林總總的宣傳海報和回收的壁報紙,似乎比大字報更耐用,如果再加上提把的設計,就可以帶著走,不但可以資源再利用,而且更貼近生活需要。在經過不斷的努力蒐集資訊及不斷觀察、試驗和改良後,終於利用學校佈告欄的回收紙,設計出符合自己使用需求的紙袋。
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我們的研究包括兩部份,第一部份是實地調查訪問。瞭解地震成因、傷害及現有防震方法,並調查坊間各種建築物類型,及常見私自改變建築物結構現象,做為研究的基礎。第二部份為建築物抗震實驗。研究發現:牆面挖空、頂樓加蓋、樓層挑高,建築物會在該處產生弱點,由此斷裂。柱子數量相同下,散開時支撐力較弱。不對稱建築物遇震時會不自然扭轉且易倒。隔震素材恰當,能有效提高耐震力,本實驗以滑軌、彈珠最好。樓頂加裝消能設施亦能減震,但設計極其不易。
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Tea is the most widely accepted and consumed beverage worldwide due to its characteristic aroma and taste. Recent studies have provided the strong scientific basis for understanding the health promoting effects and cancer preventive actions of tea. The components of tea especial the catechins are varied with the conditions of making tea. To understand and determine the chemical composition of tea is very important. Some investigations of the parameters on the storage and making of tea were carried on in this study. The kinds of tea studied were including black tea, oolong tea, green tea, and instant tea bags. A high performance liquid chromatograph combined with UV detector and mass spectrometer used to analyze the components of tea. The results showed that the composition of tea solution is dependant of the exposure of light. One of the components of tea, (-)-epicatechin methylgallate (ECMG) was oxidized to quino form. The concentrations of (-)-catechin gallate (ECG) decreased and one of new compound (M.W. 442) produced with increasing the storage time. From the results show tea made with cold water is better than that made with hot water. The ingredients in green tea were changed faster than those in fermentative black tea and oolong tea. The components of tea can be kept unchanged for a long time at low temperature. In refrigerator, the time can be extended to overnight. 茶由於其具有特殊的芳香氣味及口味,廣泛地被世人用為飲料,近年來的研究證據顯示茶具有促進身體健康和防癌功效,但茶中成分之變化,尤其兒茶素隨茶的種類、茶沖泡保存方式及置放時間而有所不同,因此對於茶中成分及沖泡方式的認知是一門重要的課題。 本實驗主要是探討茶沖泡時間及貯存條件,對於茶液所含兒茶素變化的影響,探討的茶包含紅茶、烏龍茶、綠茶及其茶包。並使用質譜儀及高效能液相層析質譜儀配備紫外光偵測器分析茶液中之成分,實驗結果顯示成分變化速率以未發酵的綠茶較發酵的紅茶和烏龍茶快;低溫儲存時,亦可延緩茶液成分的變化,例如加蓋並存放於冰箱,則茶置放至隔夜其成分均未改變;同時結果顯示成分產生變化者,主要為兒茶素氧化,如將多酚類氫氧基經氧化變成?(quino) ,其次為斷裂再產生聚合其中綠茶以不照光變化較大。本研究並經實驗發現如果以冷開水沖泡綠茶20~30分鐘,咖啡因的溶出量雖略多於沖泡2分鐘的熱茶,但各種兒茶素的溶出量卻遠高之,尤其置放至隔夜茶液成分仍無氧化現象。
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我們在生活中發現了太陽光照射到物體的時候,物體的受光背面所形成的黑影的長短,與陽光的斜度及物體的高度有密切的闕係。好像所形成的影長短很有規律性的,因此想到我們利用影長是不是可以測量出物體的實高,所以去請教了老師。我們在老師的輔導下做了一個標準竿影盤及各種斜度的燈光盤,開始做了下面幾個實驗。
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本研究利用塑膠投影片、吸管、黏膠等材料,以自製的簡易風洞測試單片翼的升力與水平推力,進而探討不同變因對雙滑管、連結雙支架之翼片爬升力量的影響,成功使用三滑管連結兩組雙支架製成一個能伸展與收縮、有節奏向上爬升的M型毛毛蟲翼片。我們又改變M型毛毛蟲的大小比例,在不同的風速下分別測試其爬升速率,發現毛毛蟲越大隻,其爬升平均速率受風速變化的影響越明顯(爬升速率變化趨勢線斜率越大)。最後我們嘗試增加背腹翼的寬度,以增大翼片面積提高升力,成功做成一隻能伸縮爬升的雙M型(三節式)毛毛蟲。
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科展作品檢索
無孤力點無交錯分割的區塊細分及五個新的Riordan組合結構
將一個集合{1,2,...,n}分成數個非空的集合(組,區塊),稱為此集合的一個分割。如果可以找到1 ≦ a 已知無孤立點無交錯分割以Riordan 數{rn}n≥0 =1,0,1,1,3,6,15,36,... 來計數。在這篇文章中我們研究無孤立點無交錯分割的一些性質。
首先我們考慮無孤立點的無交錯分割按區塊的細分。我們得出:集合{1,2,...,n}恰含k個區塊的無孤立點的無交錯分割的個數為:
其次,我們證明bn,k和多邊形的剖分有令人訝異的關連。令dn,k是用不相交對角線將凸n 邊形分成k 塊的方法。我們用代數方法證出 bn,k = dn+2−k ,k,也給了一個新的組合證明。
最後,透過對應的方法,我們找出了七個嶄新的組合結構,這些結構都是以Riordan 數來計數。
Partition the set {1,2,...,n} into several nonempty sets (blocks) and call it a partition. If there exists 1 ≦ a It is known that the nonsingleton noncrossing partitions are counted by Riordan numbers {rn}n≥0 =1,0,1,1,3,6,15,36,... In this paper we study the properties of them.
First we consider the enumeration of nonsingleton noncrossing partitions in respect to the blocks. We prove that the number of nonsingleton noncrossing partitions of {1,2,...,n} with k blocks is
Then we give a connection between nonsingleton noncrossing partitions and polygon dissections. Let dn,k be the ways to dissect an n –gon with noncrossing diagonals. We prove that bn,k = dn+2−k ,k
We also give a combinatorial proof. Furthermore, by way of the technic of bijection, we find 7 new combinatorial structures counted by Riordan numbers.
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科展作品檢索
台灣稀有水生植物蓴菜生長型態構造觀察成分分析研究
本研究針對台灣產水生植物,蓴菜之構造與生長環境、蓴菜對腸胃道常見致病細菌之抑菌效果以及主要成分暨化合物分析。由本研究結果得知,崙埤湖內之稀有浮葉型水生植物蓴菜,其生長環境為無汙染之乾淨偏酸性水源,最適合生長之生深為50-160 ㎝;水溫則為22-25℃;而蓴菜之地下根莖對表皮金黃葡萄球菌(Staphylococcus aureus)具有輕度之抑菌效果,經由分離純化得知為BS-1:沒食子酸(Gallic acid);另外,由蓴菜之葉片分離出十種成分分別為BS-2 (Kaempferol-7-O-Glucosids)、BS-3 (Quercetin-7-O-glucosids)、BS-4(5,8,4’-Trihydroxyflavone-7-O-glucosids)、BS-5 (3,5,8,3’4’-Pentahydroxy flavone)、BS-6(Vitamin E: d-Tocopherol)、BS-7 (Glyceride)、BS-8 (Phenolic A)、BS-9(Quercetin)、BS-10(Kaempferol)、BS-11(Phenolic B)。其中發現BS-8 對神經膠腫瘤細胞株有18.42%之抑癌效果,另外,BS-2、BS-3、BS-5、BS-10、BS-11 等成分,呈現良好之美白作用。This investigation is to analyze Brasenia schreberi Gmel., a native rare floating water plant in Taiwan, focusing on the plant’ s structure, its growth environment and, most importantly, the effect of chemical compounds it produces on restraining the common pathogenic bacteria in human stomach. The result indicates that the most suitable growth environment for Brasenia schreberi Gmel. is in slightly acid, pollution-free water such as that in the lake Lung Pi in northern Taiwan. The ideal water depth for its growth is 50-160 cm, and the water temperature is 22-25°C. The impractical BS-1 (Gallic acid) extracted from the izome of Brasenia schreberi Gmel. by separation and purification has a light effect on restraining Staphylococcus aureus, a bacteria in the stomach. From the epidermis of the blade of Brasenia schreberi Gmel., ten other ingredients are also isolated, including BS-2 (Kaempferol-7-O-glucosids), BS-3 (Quercetin-7-O-glucosids), BS-4 (5,8,4’-Trihydroxyflavone-7-O-glucosids), BS-5 (3,5,8,3’,4’-Pentahydroxyflavone), BS-6 (Vitamin E: d-Tocopherol ), BS-7 ( Glyceride ), BS-8 (Phenolic A ), BS-9 (Quercetin), BS-10 (Kaempferol),and BS-11 (Phenolic B). BS-8 is found to resist cancer C6 ( Glioma ) by 18.42%, while BS-2,BS-3, BS-5, BS-10, and BS-11 show an outstanding effect on skin-whitening.
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流行病的傳染過程如同一個無尺度網路,但較一般無尺度網路有著更多的變數而明顯差異,因此無法直接應用一般的無尺度網路模式來描述其傳染途徑。我建立一個新模式「無尺度流行病模式」,經由比較模擬結果與疾病管制局的數據,證實此「無尺度流行病模式」是正確與確切可用,且適用於短期暴發性傳染病與長期流行病。SARS案例研究結果,顯示影響SARS疾病傳染因子的大小是:ψ>m>γ。其中降低ψ值可使SARS確定病例至5月31日止降為143人(減少確定病例190人,相當於減少死亡21人);僅提高防疫使5=γ,亦可使確定病例減至307人(減少確定病例26人,相當於減少死亡3人)。因此強化隔離措施以減少傳染天數最為重要,且可以有效控制每日SARS新增病例,避免發生高侵襲率的現象。HIV/AIDS案例研究結果,獲知採用ψ值來進行月份模擬,則至 2005年12月HIV(+)與AIDS分別為可減少2,715與285人。而進行年度模擬結果,則至 2014年底HIV(+)與AIDS分別為可減少41,936與5,328人。無尺度流行病模式可以協助所需警戒的程度與政策決定的計畫結果。因此無尺度流行病模式在幫助政府評估社會經濟成本與健康憂慮上的有用之工具。當面臨一個全然無知的新病毒的侵襲時,如何減少死亡與傷害人數?是本研究之最終目的。因此,本研究結合了流行病、無尺度網路與灰預測,建立面對病毒侵襲,一個確切可行的對抗無尺度流行病傳染新方法,並詳細說明運作流程。\r \r \r The course of epidemic infections resembles a scale-free network. However, they are different due to more variables in the epidemic infection. Therefore, the model of scale-free networks is not enough to satisfy the reality epidemic infections. In this study, I propose a new the Scale-Free Epidemic Model. Comparison of the simulation results with Taiwan CDC report data for SARS and HIV/AIDS cases show that the Scale-Free Epidemic Model is accurate and useful. This model can be used in the short-term outbreak of infectious diseases and for the longer-term epidemics. In the SARS case study, the results show that the sequence of effect of the epidemic factors was: ψ>m>γ. The SARS confirmed cases would decrease to 143 cases (reduced 190 confirmed cases or 3 death cases) calculated to May 31, 2003, if the average infection time was reduced to two days (an optimum value of ψ). Therefore, vigorous action in isolation quarantine and treatment for SARS cases is most effective policy; the number of new cases and the attack rate would also decrease. In the HIV/AIDS case study, the simulation results of the Scale-Free Model indicates that the reduced numbers of HIV(+) and AIDS in the monthly simulation calculated to December 2005 are 2,310 and 361 and the annual simulation by December 2014 are 27,161 and 3,710. The Scale-Free Epidemic model can help determine the level of caution needed and the projected results of policy decisions. Therefore it is a useful tool in assisting the government to balance socio-economic and health concerns. The fight against a new epidemic and how to reduce the number of deaths is the main purpose of this study. So, a new method to fight against epidemics is proposed. Detailed procedures of this method are explained.
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在實驗中學2007 年校內科展,參展作品《三角形中的切圓》的研究中,研究三角形內的切圓時,發現連續切圓的圓心與拋物線的軌跡有關。於是去查資料,在偶然的情況下,翻閱《平面幾何中的小花》時,接觸了「六圓定理」。因為覺得這問題非常有趣,於是便著手證明(見報告內文)。 又發現,當移動六個圓中的起始圓時,總是在某種情況下,六個圓會重合成三個圓。繼續研究其重合的狀況,發現了馬爾法蒂問題(Malfatti's Problem)的一種代數解法。 當我試著推廣六圓定理至多邊形時,發現奇數邊的多邊形似乎也有如六圓定理般圓循環的狀況,於是著手證明,但目前尚未證明成功。而偶數邊的多邊形則無類似的結果。 ;In 2007 National Experimental High School Science Exhibition, one of the exhibit works, "Inscribed Circles in Triangles", shows that the centers of the consecutive inscribed circles has something to do with the parabola's trajectory. To learn more about inscribed circles and parabolas, I referred to literature. By accident, I am faced with the problem on six circles theorem, in the book The Small Flower of Plane Geometry(平面幾何中的小花). Out of my interest in this problem, I tried to prove it. The other results are as follows: With the initial circle of six circles moved, in certain circumstances, the six circles merge into three. Further in studying this coincidence leads to an algebraic method to solve the Malfatti's Problem. Applying six circles theorem to the odd-number-sided polygons exists the same characteristic. It indicates that the inscribed circles will form a cycle. However, it hasn’t been successfully proven. The even-number-sided polygons show no similar results.
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利用鐵離子(Fe3+)催化過氧化氫(H2O2)產生高活性自由基,並利用自由基降解汙染物的方法稱為Fenton法,然而傳統Fenton法中的鐵離子為液相催化劑,會隨降解後的汙水排放,環保署公告的廢水放流標準規定鐵離子濃度必須小於10 ppm ,為了符合標準,廢水必須加入凝集劑排除鐵離子,造成大量氫氧化鐵汙泥,造成氫氧化鐵汙泥的二度公害,且不符合綠色化學中充分利用原料及將耗損降低的主張。因上述缺點,本研究將傳統Fenton法中的液相催化劑,改利用聚丙烯酸(PPA)錯合鐵離子形成的固相催化劑,改善鐵離子會隨降解後汙水排放的缺點。實驗發現固相的鐵離子催化劑降解速率較液相鐵離子催化劑慢,但在降解後的汙水中,固相催化劑降解的汙水驗出微量鐵離子,較傳統Fenton法鐵離子會隨降解後汙水排放的現象,減少大量鐵離子耗損。
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