全國中小學科展

未得獎作品

總站該設在哪裡?—另類費馬點的研究

The definition of "Fermat Point" is that a dot, which lies in a triangle, has the minimum distance to the three apexes. In other words, "Fermat Point" has the minimum distance to three dots which are not on the same line. In the broad sense, then, in a N polygon, a dot which has the minimum distance to the N apexes could be named "Fermat Point." But what if we link up the N apexes and find out that they cannot make a convex polygon? The above is what we wish to fully discuss. Our inspiration comes from a paper on"Fermat Point." It just describes N convex polygon, so we think of putting the case to naturally polygon. The case may be that it is a concave polygon or part of the apexes which lies on the same line. We would not base our study on the conventional methods. Moreover, strictly defined, the repeated line segment will not be taken into account. That is, if the "Fermat Point" drops on the line with more than two dots on it, we just count the\r line segments except for the shorter line segments which were originally included in other studies. According to the theorem, our conclusions are as follows: 1. If N points lie on the same line segment, then the "Fermat Point"can be any point on the line segment. 2. If (N-1) points are on the same line segment, then the "Fermat Point" is on the point which two lines join together. One is that the line segment, and the other is the one which passes the remaining point and\r perpendicular to the first line segment. 3. Now there are (M+N) points. Among them, M points will make a M jog-polygon. The others all drop in the polygon. As the diagram shown beneath, we know that the "Fermat Point" drops on the point which two lines join together. The two lines must pass as many points as possible. 所謂的「費馬點」是指三角形內到三頂點距離和最小的點。換言之,「費馬點」就是到平面上不共線三點距離和最小的點。因此,我們可定義,廣義的「費馬點」即是n 多邊形內到各頂點距離和最小的點,亦即到平面上不共線n 點距離和最小的點,但若平面上n 點不能恰為n 多邊形的頂點呢?這就是我們所要討論的。由於我們的靈感來自一份關於「費馬點」的科展作品,所以我們想到,當平面上n 點不能恰為n 凸多邊形的頂點,甚或其中有一部分的點共線時,將不能以n邊形的方法來探討,但我們可以將之化為m 邊形內(n-m)個點來討論。而更重要的是,我\r 們增加了另一個限制,重複的線段將不被我們列入計算。亦即當所求點落在某一多點共線的線段上時,我們只計算該線段的總長,而不計其中重複的較短線段。根據這個原則,我們試行證明平面上三點、四點、五點及六點的可能情況,期望能從中找出足以推廣至平面上n 點的一般性。結果雖不完美,但我們總算差強人意的歸納出了下列結論:1.若n 點共線段,所求點可為所共線段上任一點。2.若(n-1)點共線段,則由該不共線點引一線與共線段垂直,其交點即為所求。3.若(n+m)個點中有m 個點為一m 多邊形的頂點,另外n 個點落在該m 多邊形內,則由兩個外頂點引直線盡可能通過最多點,該兩直線的交點即為所求。

關於渦旋〈二〉

在做這實驗之前,我花了很長一段時間思考一個問題:我如何能得到同\r 樣大小(均勻)的水珠陣列?我在家中各個角落放置許多水瓶,看看哪\r 個地方能培養出顆粒相同的水珠? 往往肉眼見到整齊排列的水珠,一經\r 顯微鏡觀察,可就大小不齊整了。\r 第一篇中的實驗,幾乎是「水珠日記」,記載冷凝過程;其中我特地比對\r 「穩定的水蒸氣氣流」與「擾動的水蒸氣氣流」、「水蒸氣氣流與凝結盤\r 間溫度差別」、「凝結盤密度差別」、「凝結因子的重量百分濃度差別」、「水\r 蒸氣氣流之流速差別」,並加以複合比對。希望能找到產生均勻排列的條\r 件–探討水分子的自我組裝機制(Self Mechanism of Water Droplets)。\r 這其中提出『均勻假說』: 當條件合宜時,冷凝下降的細微水珠會產生\r free vortex ring,形成整齊的渦環組合,進而產生均勻排列的細微水珠陣\r 列。\r 實驗是藉由溶液密度小於水的設計,讓水蒸氣冷凝於液面上,並且因密\r 度較大而下沉。設計的要點是:儘量減少細微水珠自冷凝後的堆疊\r (coalescence),以呈現水珠原貌。\r 在第二篇實驗中,將對渦旋比例尺修正。渦旋本身難測大小,在空氣中\r 也不易觀察,但是若由水中觀看,可藉由空氣蕊長短估算。這次更進一\r 步考慮到排水速率、水深、排水口形狀、與極值。\r \r I have tried to ask a famous math professor if he can create a formula\r describing the ordered array of water droplets。〝Then, I should study Physics\r first !〞He said。\r Condensation is the thing we live with , being found everywhere, passing\r without notice。But we never know0 when it does start?\r This experiment presented here is actually the diary of the growth of water\r droplets through condensation。Through convection and vortex ring, it\r discusses the self assembly mechanism of water droplets and peep into the\r uniformity of the size of water droplets。\r Here, vortex ring plays an important role in the self assembly mechanism of\r water droplets which is not triggered in the daily life。\r By coalescence, water droplets grow bigger, but are not round again。We used\r the polymer film as template and designed the solution lighter than water, so\r the minute droplets will sink to the bottom and layer by layer。After seconds\r we may have multilayers of ordered array。\r This is the first step in discovering the uniformity of water droplets, besides, I\r made some correction to the Vortex-Ruler。Vortex-Ruler will be useful in\r researching the flying mechanism of butterfly and dragonfly as to judge\r which one induces more vortices。

視覺中的光學現象

人眼所見點光源四週的光芒(我們稱為"星星長角"),夜間瞇眼時所見向上下方向射的特別長的光芒(我們稱之為"炫光萬丈"),這二種視覺中的光學現象無法用相機拍攝,但眼睛卻能夠看見。書上及網路上均無法找到合理的解釋。因此,我們設計了數個實驗來研究這些光學現象的成因。我們發現了星星長角的成因是由光對眼睛表面刮痕的繞射和光對眼睫毛的繞射雙重原因所產生。而炫光萬丈的成因則是光線經過眼球表面淚膜層的部分反射及部分折射所造成。The purpose of the research is to verify possible reasons of some optical phenomenon in human vision, including the star shape of a dot light source and glare upward or downward when one narrowing his/her eyes. These optical phenomenon can be seen by naked eyes but can not be taken photos with a camera. We find no detailed explains which can explain the cause of glare upward or downward on the internet or in books. So we designed several experiments trying to find out the cause of these optical phenomenon . In experiments, we figured out that diffractions by notches on the surface of eyes and eyelashes are both responsible for the star shape of a dot light source. The cause of glare when narrowing eyes is that partial reflection and partial refraction of light take place between boundary of air and tear film and boundary of tear film and cornea. The appearance of glare is closely related to the thickness of the tear film . When we narrow our eyes , the tear film is thicker. The thicker the tear film is ; the longer the glare is .Also, bended extent influence the length of glare. We figured out that the more bended the tear film is ; the longer the glare is.

嘖目稱奇的大豆卵磷脂

本研究目的是探討大豆卵磷脂對於老化及學習記憶能力是否有改善之功能。以 24 隻 SAMP8 小白鼠,分為大豆卵磷脂組及對照組,飼養 8週。經由主動迴避試驗、單次被動迴避試驗,測其學習記憶能力;另測量其腦部丙二醛(MDA)之含量,評估其老化的程度。由實驗結果顯示,在主動迴避試驗中,大豆卵磷脂組被電擊次數有減少趨勢;在單次被動迴避試驗中,大豆卵磷脂組停留在明室的時間高於對照組。而在 MDA方面,大豆卵磷脂組腦中MDA含量低於對照組。由上結果推測大豆卵磷脂對於抗老化及學習記憶方面都有改善的功能。 The purpose of this research was to study the effects of soybean lecithin on improving the aging process and learning and memory abilities. The first part of the experiment is to raise 24 SAMP8 mice eight weeks, and divided them into group A and Group B. We tested them memory power by Active shuttle avoidance test and Single-trail passive avoidance test, and tested their degrees of the aging by the content of MDA. The result demonstrated that there was a decreasing tendency in times of being hitting in group A during Active shuttle avoidance test. The time which group A stayed in the bright room was higher than group B during Single-trail passive avoidance test, and the content of MDA in group A was apparently all less than group B in the experiment of MDA. So we can get the message that Soybean Lecithin has the improvement of ameliorating the speed of oxygenation and increasing memory power.

蓮花自潔效應之成因機制

奈米科技是二十世紀末、二十一世紀初新興的科學技術,由於它是在1~100 nm(n = 10-9)的尺度內改造原子及分子排列,創造新物質【1】,將顛覆傳統改造物性,被預言將帶來人類的第四波工業革命,對物理、電子、光電、化工、材料、生醫、機電各領域帶來巨大衝擊。『蓮』是世界上最早的被子植物之一,在一億四千萬年前就生長在地球上,蓮的分布甚廣,從印度、中國、日本、北美到西伯利亞到處都有蓮的蹤跡。蓮的生命力強,很能適應環境,美國加州大學曾試驗培植古代蓮子,經過1300 年的沉睡,古代蓮子仍然正常發芽【2】。台灣的蓮花是十七世紀的移民,自中國帶來種植的。『奈米科技』和『蓮』這兩個不同年代的產物名詞如何連結在一起,他們怎樣相互依存;這正是本文討論的重點,也是了解『奈米科學』很好的例子。本文藉出汙泥而不染,闡述蓮花的自潔(self-cleaning)效應。一般在奈米技術中,簡稱『蓮花效應』【3】,包含清潔機制、成因;使用觀察紀錄自潔狀況情形,幫助對蓮花自潔過程的掌握。期望能對具有蓮花效應的奈米結構提供良好的意見。本研究的結果發現,蓮花效應強的植物,幾乎具有高抗水性。而抗水性是來自奈米結構和表層蠟質,這兩個特質也是蓮葉、芋頭葉等高蓮花效應的植物所具備的,所以我們推論:奈米結構和表層蠟質越發達,抗水性越好,則植物葉面的蓮花效應越強。Nano technology is one of the most advanced technologies now. Since it will alter and rearrange the fundamental structures of atoms and particles within the space of 1~100 nm (n=10-9) the coming industrial revolution depends on it. Nano technology will pose dramatic impact upon a variety of specific fields including physics, electronics, photon electronics, chemical industries and so on. Lotus is one of the most primitive covered-seed plants. It has existed since 140 million years ago and has spread in wide areas. The University of California made lotus seeds that have been frozen for 1300 years sprouted. The Taiwanese lotus seeds were transported from China in the 1600s. The researchers are to probe into the relationship between the nature of lotus and nanotechnology to understand the potential significance of this newly developed technology. The researcher employed the direct observation and tape recording to collect the objective data of the individual growth steps of lotus to analyze the self-cleaning effect of the lotus. In the conclusive part, the application of the Lotus Effect and the creative technology will be discussed and analyzed with the hope to prescribe both a conclusive experimental principles and a further direction for the manufacturing systems related to the developing Lotus Effect. The researchers of the study found that those plants, which have high quality of Lotus Effect, are given the nature of resisting water, which is the consequence of two features namely, the nano-structures and the surface wax. And the leaves of lotus, potato all have these two features. Therefore, it is inferred that the more efficient mechanism of the nano-structure and surface wax and Lotus Effects the plants are, the more effects of the water-resistance function will the plants achieve.

利用奈米級二氧化鈦(Tio2)在不同的變因下降解膠原蛋白之研究

本實驗使用奈米級二氧化鈦能經紫外線催化,分解空氣中的水分子產生自由基,攻擊膠原蛋白中碳與氫鍵結的部份,使膠原蛋白的分子量成功的從300000 減少至少到20000 以下。其次,利用紫外線波長或酸鹼值的變因之下,控制降解出來的分子量大小。利用此法可在4個小時內得到很好的降解效果,不僅可以節省反應所需的時間,所需的成本也比當今所使用的酵素降解法來得低。 其次,我們檢測降解完後膠原蛋白的活性,發現只要不照光超過2 小時,膠原蛋白所剩的活性還不錯。如此一來,我們就可以利用此法快速的製造出有用的膠原蛋白了。 ;In the experiment, we use the properties of TiO2 which can be catalyzed by UV rays and breaking the molecules of H2O and produce free radicals that can attack the bond between carbon and oxygen in collagen, degrading collagen's molecular weight from 300000 to at least below 20000. We also use different UV rays and pH to conduct the experiment, controlling the molecular weight by degradation. By using this technique, we can get good effect of degradation in 4 hours. It can not only cut back the reaction time, but also costs much lower than the way using enzyme to degrade collagen. Furthermore, after the degradation of collagen, we also carry out the experiment to make sure whether collagen is “alive” or not. We have got the result that collagen can still work if it is not shone under UV rays more than 2 hours. In this way, we can use the technique to produce useful collagen rapidly.

枯木潛盾機──石氏煙管蝸牛 (Euphaedusa sheridani shihi Chang) 取食策略之研究

When one time we beautified our campus. It made us meet the snails, Euphaedusa sheridani shihi Chang, unexpectedly. Maybe snails make people associate with the holes on vegetables tops in thinking. Do all of the snails make vegetables tops as their food? We compared with the weight of the wood which has been stayed by snails or not. After a week, the weight of the wood which has been stayed by E. sheridani shihi Chang decreased obviously. It showed they also make wood as their food. What do they decompose wood become? First, we used the basic Carbohydrate's detection means to test the eluate of the wood which has been stayed by E. sheridani shihi Chang. However, we found both the eluate of the wood which has been stayed by E. sheridani shihi Chang or not can examine the Pentose out. So next, we plan to use SDS-PAGE to analyze the left enzyme on the wood, and use it to prove whether they secrete enzyme in mouth to decomposed wood or not. In addition, the holes these snails made and the environment are connected. By means of changing light, temperature and humidity to experiment with how much wood can these snails decompose. We found in the dark, about 20℃ and moist environment, they could decompose the wood the most. Finally, the holes they made on the wood also have its ecological niche. They decomposed the wood not only hastened the dissolution of the wood, but also provided the microhabitat for alga, fungi and small bugs.一次綠化校園的活動,製造了我們與石氏煙管蝸牛的邂逅。蝸牛,或許使很多人想到蔬菜上的洞,但真的所有的蝸牛都以蔬菜為食嗎?比對有無蝸牛棲息的兩組木頭,結果一星期之後有蝸牛棲息的木頭重量明顯減少,顯示蝸牛也以木頭為食。那麼牠們把木頭分解成什麼呢?我們先以基本的醣類檢測方法,檢測蝸牛棲息過的木頭表面洗出液,不過發現不管有無蝸牛棲息皆可檢驗出五碳醣,接著預計用SDS 膠體電泳看是否可以分離分析出蝸牛在消化木頭時殘留在木頭上的酵素,以證明蝸牛是否在口腔分泌酵素以分解木頭。至於環境和蝸牛消化木頭的關係,我們藉著改變光線、溫度、溼度等變因進行實驗,發現牠們在陰暗、潮濕、約20℃的環境下可以分解最多的木頭。最後,牠們分解木頭形成的洞也具有其生態意義,不僅加速木頭的分解,也製造了微棲地提供藻類、真菌及小型生物的生存空間。

芯電感應

Based on Ampere,s Law, the magnetic field intensity of the solenoids is B=μ0μr?n?I, where μ0 is the magnetic permeability of free space, μr is the relative magnetic permeability, n is the number of coils per unit length and I is the solenoidal current. The end magnetic field of the solenoid must multiply by one half. According to the above result, it can be greatly strengthened by the addition of a ferromagnetic core. First, we observe three different inserted materials of coils (wood, iron and magnetite), whose magnetic induction in different solenoidial current. By experiment, when the iron and magnetite materials were inserted into the coil, it would produce larger magnetic induction. The calculated relative magnetic permeabilities of wood, iron and magnetite materials are 0.57, 18.37 and 18.32, which are close to the reported paper (1). When the driving field is removed, the fraction of the saturation magnetization of the magnetite is retained, which is called hysteresis and is related to the existence of magnetic domains in the material. In the second part, we change the frequency of circuit switch, which induced different current. Compared with the result of the first part, it would fit the result, which is the induced magnetic field is proportion to the solenoidal current. 根據安培定律,螺線管的磁場為B=μ0μr?n?I。其中μ0為真空中的導磁率,μr為相對的導磁率,n為單位長度的線圈匝數,I則為通入螺旋管的電流。至於螺旋管的端點磁場須再乘上1/2。所以根據上述的結果,當螺旋管插入鐵磁性物質,會增強螺旋管的磁場。首先,觀察三種不同的芯物質;非鐵磁性材料,軟磁材料,硬磁材料(木棒,低碳鋼棒,磁鐵棒)在不同的外加磁場下的感應磁場,得到芯物質的磁化曲線,而計算出來的相對導磁率分別為0.57, 18.37 和18.32與參考文獻(1)接近。而當外加磁場移走時,硬磁性物質的磁性仍然存在,稱為殘磁現象。在第二部分,我們改變線路開關的頻率。發現不同的開關頻率,會得到不同的螺旋管電流,而造成不同的感應磁場。再度驗證了感應磁場大小是正比於螺旋管電流的大小。

以廢找廢~讓重金屬離子無所遁形~

在相對較高氧化電位下的前處理,這樣的活化步驟已被普遍接受。藉由這樣的活化步驟,廢煤渣(傳統鋼鐵業)轉變成能夠有效偵測微量鉛金屬離子的催化劑。微量鉛金屬離子的偵測是藉由方波剝除伏安法進行。在最佳化參數下,偵測鉛金屬離子的靈敏度為11.482μA/ppm(斜率??),線性範圍為0.1-2ppm。最後,照光設備之應用亦可用來提升偵測鉛金屬離子時之靈敏度。最終實際應用則取天然的水進行實驗之驗證。The preactivation process (i.e., preanodization) at very positive potentials has been accepted as the prime activating procedure. By using the preactivation process, waste cinder (from steel industry) were converted into an efficient catalyst in the determination of Pb2+ in cinder-modified carbon paste electrodes. The possibility of determining Pb2+ at trace levels was examined by square-wave anodic stripping voltammetry. Under the optimized analytical conditions, the sensitivity, linearity, and detection limit are 11.482 μA/ppm, and0.1-2 ppm (r = 0.974). Finally, the lighting was also used to raise the sensitivity of the determining Pb2+. The practical applications were demonstrated to measure trace Pb2+ in natural waters.

一個也沒漏掉,一個正有理數的排序的研究

本文中我們探討一個有趣的數列。這個數列有一個非常特殊的性質:將數列相鄰兩項的前項當分子,後項當分母,所產生的分數數列,恰好會出現所有的正有理數。 這個特殊的性質表示,可以將正有理數按照這個方式作排序,這個排序將完全不同於常見的正有理數排序的方法。 (1). 在正有理數的排序的結構中,我們做出許多有關於此數列的定理。 (2). 用數學歸納法證明此分數數列涵蓋所有正有理數,且每一正有理數只出現過一次。 (3). 將數列分割後,利用試算表製成數列規則表,並整理出快速的方法將數列表達出來。 (4). 將an 數列排成“樹"的模式,可更快速的把正有理數寫下來。 (5). 最後,設計出搜尋正有理數的演算法,解決在分數數列中第n個正有理數會是多少;以及正有理數會出現在數列中第幾項的問題。 Let’s discuss an interesting sequence. There is a very special quality in it. In this sequence, choose two numbers, which are close to each other, and suppose the first number as “member” while the second one as “denominator.” Then we can get a fraction sequence that includes all of the positive rational numbers! According to this special quality, we can arrange positive rational numbers by the following method. Then we can get a brand-new way of the arrangements. (1). We can find many theorems about this sequence according to this special arrangement of the positive rational numbers. (2). We can prove the rule that this fraction sequence includes all of the positive rational numbers by mathematical induction. Furthermore, every positive rational number appears only once. (3). After dividing this sequence into several parts, we can get a sequence rule list by using trial balance and find a faster method to express the sequence. (4). Arrange the an sequence by the tree model. By this way, we can get all of the positive rational numbers much faster. (5). Finally, we can develop the operation method to solve the questions that what position would one positive rational number be in the sequence and what is the first, second, third or nth positive rational number of the sequence.