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我們自然課上種子的構造和發芽的時候,老師要我們把綠豆浸一個晚上。在培養皿裡鋪棉花,把十粒浸過的綠豆,讓它發芽。我們從它們冒出胚根,長出莖葉……,一直觀察記錄到倒覆、枯萎。由這一試驗的結果,引起我們這一群研究不同植物發芽過程的興趣,並且嘗試作各種芽菜的培育。
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膜粒通道---蛋膜粒子通道滲透速率之研究
這是一項以蛋膜為對象的研究,並配合化學課及生物課所學的滲透原理。藉由電導度計測量電導度的變化,間接推得濃度以探討粒子經由蛋膜的滲透速率,分別探討不同濃度的電解質溶液、相同陰離子不同陽離子的溶液、及相同陽離子不同陰離子的溶液,並且探討離子溶液受磁場N、S極、不同位置的影響,以及其他粒子溶液通過蛋膜的情形,加以分析討論。一開始使用電導度計測量實驗裝置一號蒸餾水端的電導度變化情形,研究後發現問題,改善成新的實驗裝置二號,確定它的滲透速率情形。再度發現問題,設計實驗三號,測量離子溶液端及蒸餾水端距蛋膜0 cm處的電導度變化情形,企圖了解各種離子的蛋膜滲透、擴散與磁場的相關性。
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本研究所探討的主題是一道分割棋盤的題目:\r 給定一個黑白相間的mxn棋盤(設m為縱向邊,n為橫向邊),將其分割成若干個面積大小都不等的矩形區域,且每個矩形的黑格和白格個數相等。設f(m,n)為符合上述條件的最多分割矩形的個數,則f(m,n)是多少?\r 在研究過程中,我們首先藉由對各棋盤進行分類,利用不等式的運算找出其中的關係,求得當m=n以及mn=k(k+1) 時(其中K為正整數)的f(m,n)值,並構造出其分割方法。而k(k+1)
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My Science Fair project last year tested a local native plant for it’s toxic effects on insects (fruit flies), bacteria, fungi, and viruses. The root of the plant Lomatium dissectum, had been used by the Salish People to control lice and other insect pests in horses and cattle. The root was also used to kill fish, which could then be harvested by women and children. The fish killed in this way were not harmful to eat as long as they were consumed soon afterward. I have found also that fishing with the aid of plant toxins was formerly very common in tropical Africa. \r Lomatium dissectum, grows in dry rocky slopes in conjunction with Sagebrush.\r Many desert plants produce toxic substances that inhibit the growth of competing plants\r nearby. This adaptation is called Allelopathy. In a natural ecosystem, Lomatium does not\r kill fish because it does not grow beside creeks. But this raises the question of whether\r allelopathic plants growing outside their natural ecosystem are having a toxic effect on\r animal life. There are introduced invasive weeds that are allelopathic, such as\r Knapweed,growing near streams. And there are crop plants that are allelopathic – Rye and\r Alfalfa. Do these “natural herbicides” also kill fish? Walnut trees are allelopathic and\r compounds from Walnut kill fish.\r If this effect does go beyond toxicity to other plants, it would be an important\r consideration to environmental guidelines for private land bordering on streams and\r rivers. The B.C. Ministry of Environment notes the importance of shade cover for\r spawning streams. It does not recognize the harmful effects of introduced plants. Yet,\r when we were purchasing supplies for our Koi Pond the pet supply company offered a list\r of “Some of the Worst Plants to Have Around Koi”. We do not know if the introduced\r allelopathic plants are poisoning fish or reducing fish stock by poisoning the food that fish\r need.\r Science Fair rules do not allow any research that is expected to have any negative\r impact on vertebrate animals. Because of this, I have decided to test the effect of\r allelopathic plants on fruit flies (Drosophila). Fruit flies are similar to fish since, during\r larva and pupa forms, they live in direct contact with their culture media. I will also be\r testing the effect of allelopathic plants on Planaria (Turbellaria), an aquatic invertebrate.
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Drought and inundation are two unusual natural disasters in Taiwan. The two natural disasters\r have some relation of abnormal rainfall become more and more in Taiwan. So it let me think about\r can climate vicissitudes make the chance of abnormal rainfall become more?\r The study have researched the chance of abnormal rainfall by "rainfall duration" and "total\r rainfall". It collect the day by day total rainfall from 1960 to July 2002, collect locals are Taipei,\r Taichung, Kaohsiung and Hualien. Than enter the data into the computer, let computer calculation\r total rainfall, rainfall days, heavy rain days, pouring rain days and torrential rain days. Then\r analysis the tendency of long-term change.\r According to the analysis, the chance of abnormal rainfall happened become more in Taipei,\r Taichung, Kaohsiung and Hualien. The ratio of Hualien and Kaohsiung is the most obviously. It's\r also find that there temperature and total evaporate became higher, the total sunshine duration\r became lower. Then El Nino have some influence in abnormal rainfal. In El Nino year, total rainfall\r will become lower. When La Nina year, the total rainfall will become more in Taipei and Hualien.\r Then the long influence is clearly in Taipei.\r 乾旱與水災是台灣地區相當常見的二項天災,這二項災害的發生都與異常降水有直接的\r 關係。近年來台灣地區因異常降水造成的天然災害,似乎有逐年增加的趨勢。因此讓人聯想\r 到氣候變遷是否會導致異常降水頻率增加。\r 本研究主要由「降雨時數」與「降雨量」二方面探討異常降水發生頻率。先收集台北、\r 台中、高雄、花蓮四地自1960 年至2002 年七月三十一日之逐日雨量資料,將資料輸入電腦\r 後,統計各站歷年降雨量、降雨日數、大雨、豪雨、暴雨日數,並分析長期變化趨勢。\r 分析結果,台北、台中、高雄、花蓮四地異常降水發生機率,有增加的情形;其中以花\r 蓮及高雄變化的比例最高。再與其他各地氣象要素比較可發現,可能與氣溫及蒸發量數上升,\r 以及日照時數縮短有關。另外聖嬰現象也可能對異常降水有長期性的影響。一般而言聖嬰年\r 雨量減少,反聖嬰年台北、花蓮地區雨量反而會增加。而長期性的影響,以台北地區最顯著。
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在三年級的下學期,上自然課時,我們學習了紋白蝶的生活史,牠由卵一幼蟲一蛹一成蟲,一生中四種形態,我對這個問題感到非常有趣,紋白蝶,以外的蝴蝶是不是也是一樣呢?有一天在家裹果園的馬鈴草叢葉片上,捉到了好幾個圓圓的卵,說不定是蝴蝶卵,如果這樣,它不是就會變成美麗的蝴蝶嗎?第二天把它帶到學校裹請教賴老師,賴老師鼓勵我們飼養它,大家便在賴老師的指導下:從事飼養的活動。
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台灣水生食蟲植物~ 絲葉狸藻捕蟲行為及消化功能的進階探索
The “Insectivorous Plants”﹐ the first historical publication by Charles Darwin﹐contained the detailed observations and meticulous descriptions of various carnivorous plants and had become the most important reference for the study of carnivorous plants﹒ But the prey mechanism and digestive function of the bladder traps of the Utricularia were not well described﹒ The present study has a great success in these fields which include the volume change of bladder traps before and after firing﹐the spontaneous pressure relief of the bladder traps even without being triggered by prey, and the quadriceps visible absorption process﹒ The last two findings are not yet publicated. This laboratory experiment is carried out with Utricularia Gibba﹐a native species of Utricularia in Taiwan﹒ Through static and dynamic observation﹐we find that bladder traps suck in water by 12-25% of body volume change, and the bladder traps release internal pressure spontaneously under long period of waiting, despite not being triggered﹒ We can also easily demonstrate the absorption process of quadriceps by manually triggering the bladder traps to suck food color solutions. All the events above can be clearly seen under microscopy﹒達爾文是最先對食蟲植物作深入且完整研究的科學家,至今他的著作仍是研究食蟲植物的重要資料,但在其內容中對狸藻捕蟲囊捕蟲行為及消化功能的研究觀察並不完整。本實驗使用簡單的方法,在這方面有突破性的進展,包括捕蟲囊捕食前後的體積變化,自發性舒張及囊內腺毛對於食用色素的消化吸收,後兩項發現及實驗均未曾出現在文獻資料中。 本實驗以台灣本土水生食蟲植物絲葉狸藻(Utricularia gibba)為研究對象,由靜態及動態觀察,顯示捕蟲囊捕食前後體積變化為12~25%,且即使在沒有捕到水中生物的情況下,也會有自發性舒張以解除囊內壓力的現象。捕蟲囊內四爪腺毛消化吸收功能的整個過程,可藉由食用色素加以呈現,並清楚的在顯微鏡下觀察到這些現象。
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每當我餵我家的魚時,都會先拍魚缸,久而久之,只要拍魚缸,魚就有了靠過來的反應。於是我想低等動物是不是也有相同的情形呢?於是我就用有明顯頭部,但不是很高等的「渦蟲」來做實驗,加以探討。
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本研究以碳化矽(SiC)奈米粉末加入去離子水中,插入銅電極加以電壓進行其表面帶電性的研究。研究中發現SiC奈米粉末的表面帶有負電荷,且加以電壓後,SiC奈米粉末會沉澱下來。利用場發射掃描式電子顯微鏡(SEM)及X-光繞射儀(X-RD)檢測其性質,發現加以電壓使奈米粉末失去電荷而聚集沉澱。同時經由製作不同酸鹼度SiC奈米粉末溶液的陽極極化曲線發現pH值越大,SiC奈米粉末表面電位越高,開放電路電位越小。本研究實驗過程中發現pH值2之SiC奈米粉末溶液加過電壓後,正極生成一透明薄膜狀物質,極有可能是導電鍍膜,應用價值極高。本研究已先進行微硬度試驗與金相實驗,將由長庚大學機械系研究所進行更深入檢測與研究。The electrochemical behavior of the SiC-nanopowder in deionized water was studied. The electrochemical cell was composed of two pure copper electrodes, across which different voltages were applied. The morphology of the nanopowders or even with reacted products was examined using field emission electron microscope(FESEM) and the corresponding phases were identified with X-ray diffraction method(XRD). The experimental results show that tha nano-powders precipitated at the surface of the anodic copper electrode and in the same time the nanopowders in the solution aggregated when 20 volts were applied across two electrodes. That is, net negative charge could be induced around the nanopowder. Deposition rate of the aggregated powders in the various pH-value solutions was evaluated and the aggregated powders were examined with FESEM. The higher Zeta potential of the SiC-nanopowder was examined as the nanopowders immersed in the higher pH value solution. The nanopowders aggregated themselves as the pH value under 2. The anodic polarization behavior of the copper electrode in SiC- nanopowder solution was measured and the results were compared with the aforementioned tests.
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一般人多將水果去皮後食用並丟棄,而傳統上含糖量多的水果也是釀酒的主要原料,因此我們嘗試將果皮等食物殘渣或廚餘加以利用,進行酒精發酵。 實驗中我們主要探討廚餘發酵時糖度與pH值的變化,以及將發酵液蒸餾製成酒精之可能性。從實驗得知果皮、果肉、白飯及麵包等在發酵過程中糖度及pH值有下降的趨勢。各種發酵液經蒸餾後所測得酒精度以麵包最高,達10%;白飯為6%;果肉、草莓為4%。而果皮發酵液蒸餾後的酒精度,則以鳯梨皮、西瓜皮及甘蔗皮酒精度為3%較高。若改變發酵溫度及酵母量可提高酒精度,鳳梨在35℃、3%酵母量時達15%;麵包則在25℃、1%酵母量時,達17%。我們發現雖蒸餾出酒精度僅在4~10%,若能二次蒸餾使酒精度達到75%,便可作為藥用酒精,或20%~40%可作為食用酒精,未來潛力無窮。
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「排」出學問來~探討各種不同因素對排水孔排水的影響
一個課堂上的流水實驗,引發了我們的好奇心,針對排水孔排水的情況加以探討,進而討論水流的運動及觀察漩渦的產生,有了一些發現,希望能應用在生活中。整個實驗研究獲得的結論如下:一、市面上排水孔蓋的形狀以水滴形孔及圓形孔較常見,大小以直徑7.8公分的為主。二、排水孔的樣式、孔的大小及數量、排水量的多少、排水孔的位置及有無擾動排水等都會對排水孔的排水造成大小不同的影響;其中以螺旋形樣式、孔不可太大、孔數量可以多一點為較佳的排水孔蓋條件。三、排水孔蓋的孔越大或數量越多,排水速度就越快;採用螺旋形樣是排水孔蓋的排水較快,漩渦也較快產生。四、水經由流動、碰撞、轉彎,使得產生旋轉而形成漩渦,一般所見都是順時針旋轉的。以上發現讓我們能應用在打掃積水時更有效率。以前在打掃積水時會有些做法不太對,我們常會一直往排水孔位置撥水,其實擾動會破壞漩渦,使排水時間加長。所以,當積水有漩渦時,應該不要去擾動破壞水平面;而當積水沒有漩渦時,才可以藉由擾動撥水,使水位增高後停止擾動,藉由較高水位使得比較容易產生漩渦,增加排水的速度。
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