全國中小學科展

二等獎

榕樹粗萃取液對種子萌發及生長之影響

相剋作用是指植物在代謝過程中釋放出有毒物質以抑制本身或鄰近植物種子萌發及植株發育生長的過程。一般認為,榕樹是具有相剋作用的常見植物,但很少見到相關的文獻探討。本實驗利用榕樹不同組織萃取液,以小白菜、結球白菜與阿拉伯芥作材料,探討該萃取液對上述植物發芽與生長之影響,結果顯示榕樹葉萃取液所造成之影響較顯著,不同榕樹組織的萃取液、不同濃度的萃取液對不同植物所產生的效果不盡相同,針對不同生長期的植物進行處理所造成的影響亦有差異。進一步以管柱層析法與高壓液相層析法(HPLC)分離葉萃取液,結果發現以正己烷和乙酸乙酯75:25為沖提液的條件下,於HPLC的層析圖中分離時間約8分時所流出的物質具最明顯的抑制作用。電泳剖面分析顯示處理與未處理間有些許蛋白質條帶差異,此變化蛋白可能與植物幼苗對該萃取液之耐受性有關。利用核酸微陣列(microarray)對榕樹萃取液處理之阿拉伯芥植物進行基因表現分析,發現榕樹萃取液對植物部分基因表現也有促進和抑制的情形,經由基因體與蛋白質體分析法可推論出一些受影響之相關基因。 Allelopathy was defined as a phenomenon which certain plant species, by secreting metabolites to the environment, can suppress the growth of themselves, seed germination and/or growth of other plants in the same habitats. Banyan (Ficus microcarpa L.f.) is a plant species in our campus likely to have allelopathy effect. However, documents describing such action on allelopathy were rare. In this study, we applied the crude tissue extracts including leaves, stems, roots of banyan onto the germinating seeds of Pai-Tsai (Brassica rapa L.ssp.chinensis(Rupr.(Olsson))), Chinese cabbage (Brassica pekinensis Rupr.) and Arabidopsis(Arabidopsis thaliana, ecotype Columbia-0) to study the effects of such plant extract on the germination and seedling growth of other plants. It is found that allelopathic effects on seed germination vary among different tissues used for extract preparation. Different concentration of the extract also yield various degree of allelophathic effects. It is also noted that the application of extract onto the post-germinated sprouts has less effects on plant growth. The extract of leaves was subsequently chromatographed over silica gel using hexane/EtOH gradient solvent system and HPLC. The result showed that there was one fraction about 8 min in the chromatography of HPLC eluted with 25% EtOAc in hexane had the most inhibitory effect. SDS-PAGE analysis on the electrophoretic profiles of water soluble proteins has explored a different band pattern between the treated and non-treated sprouts. The observed band difference might provide a clue for exploring proteins which reacted differently upon the application of extract. DNA microarray analysis on the effect of banyan extract on Arabidopsis gene expression has also been employed to characterize genes responsive to the allelophathic treatment. Cross-comparison between the differential transcript and protein profiles will reveal key regulators in plants experiencing allelophathic condition. \r

燃料電池用之磺酸化SEBS-奈米粒子複合膜製備與性質研究

聚苯乙烯(S)-聚乙烯(E)-丁二烯-1(B)-聚苯乙烯(S) (polystyrene-block-poly(ethylene-ran-butylene)-block-polystyrene,簡稱SEBS)是目前直接甲醇燃料電池的質子交換膜研究中常用於與Nafion比較的膜材。Nafion的價格昂貴,且其高甲醇滲透率將造成電極毒化,故本研究探討不同製程與添加不同奈米粒子所製作之質子交換膜特性,以有效降低甲醇滲透。結果發現,添加之ZrP為層狀結構,增加甲醇通過親水區域端的難度,能有效阻擋甲醇滲透。且藉由磺酸根官能基團,以及本身帶有質子傳導性質,所以與Nafion的PTC數據差距不大,因此C/P值較Nafion高。未來可改變不同磺酸化程度,並在SSEBS內添加不同奈米粒子,並對於質子交換膜的持久性及實際應用之探討。

利用浮沈子測量液體表面張力並演示"Cheerios Cheerios effect"

密閉容器置入待測液,放入浮沉子,施加壓力,當浮沉子恰要沒入液中瞬間,因表面張力的總力達極大值且向上,外加壓力(p1)為極大值,浮沉子沒入液中;液面減壓,當浮沉子在液面正下方時,外加壓力 p2,量 p1、(p1- p2),浮沉子的質量 m,外半徑 R,及玻璃管的體積 G V ,可求得液體表面張力。 液面再減壓,浮沉子恰要露出液面時,表面張力的總力達極大值且向下,外加壓力(p3)為極小值,量 p3、(p2- p3),浮沈子的質量 m,外半徑 R及 G V ,應亦可求得表面張力;但實驗時浮沉子漂移到容器邊,並吸附在器壁上,因此發現浮沉子的”Cheerios effect”。 利用浮沉子和容器的相吸及相斥現象,可解釋西式早餐的小榖片放入牛奶中為何會漂移到碗緣,並支持 Vella在 2005 年 9 月份美國物理期刊(AJP)認為 Cheerios effect的成因除了由於接觸角不同外,浮力、重力、表面張力共同作用,使小榖片間有相吸、相斥現象。 The experiment apparatus is equipped with a Cartesian diver by using a glass tube with air trapped inside that floats or submerses in a closed vessel containing liquid. The external pressure may be varied with a syringe and measured with a water manometer. The maximum pressure P1 inside the vessel is measured when the diver is just about to sink, where the surface tension that acts on the diver is upward. Then the pressure P2 of the vessel is measured when the diver is just beneath the liquid surface, where no surface tension acts on the diver. Finally, the surface tension is calculated from P1, P2 and the radius of the diver, R. When the pressure inside the vessel is decreased, the diver will rise. As the diver is about to emerge from the liquid, we get the minimum pressure P3 inside the vessel, and the surface tension that acts on the diver is downward. By measuring P3, P2, and R, the magnitude of surface tension is found to be the same as above. When the diver is just about to sink into the liquid, it floats to the center of the vessel. When the diver is about to emerge from the liquid, it sticks to the wall of the vessel. This phenomenon is named the “Cheerios effect.” Our results again strongly support that the cause of the effect is due to the different contact angles between the diver and water, as well as the balance of gravity and surface tension in the case of the sinking diver, and the balance of buoyancy and surface tension in the case of rising diver as Vella claimed in his paper (AJP 73, 817 (2005)).

以瑞利準則探討點描畫派最佳觀賞距離

19、20世紀的後期印象派中,點描派為最吸引人的畫派之ㄧ,而喬治‧秀拉(Georges Seurat)即是其畫派之代表人物,因此,設計實驗時以秀拉的畫風為中心。\r 本研究以Photoshop繪圖模仿點描派之作品,?探索物質的本質,選用三原色為混色的原色,來觀察混色後對畫作的效果。研究中,以分析兩亮點之大小、距離與觀測距離的關係來設定點之尺寸,再進一步分析三原色點之觀測距離、比例及三原色點之佈點方式對混色效果之關係做為實驗主軸,並以瑞利準則判斷之。\r 希望藉由本實驗能以物理學的角度瞭解點描畫派之作品,同時,設法將點描畫數位化,並希望找出欣賞點描畫最佳情況,提供賞畫者最好的視覺享受。

結合奈米金粒與DNA適體的金黃色葡萄球菌快速檢測系統

金黃色葡萄球菌是生活中常見的病原菌之一,因其抗藥性日益嚴重,是大家所熟知的超級細菌。 目前醫院對此菌的檢測方式,從培養到獲得結果大約需要兩天,對許多感染此菌的重症患者是無法接受的醫療時間延誤。 有鑑於此,本研究利用創新的適體、光電及奈米技術發展一個可以快速偵檢金黃色葡萄球菌的系統。 適體為具有與抗體同樣分子辨識功能的寡核酸。我們利用DNA適體篩選技術,獲得能夠專一地辨識金黃色葡萄球菌的適體序列,進一步發展高敏感度細菌檢測系統,並測得靈敏度近個位數的金黃色葡萄球菌。本研究亦結合奈米金與共振光散射原理,以簡便的二極體雷射與偵測裝置,可快速判定檢測樣品中是否有金黃色葡萄球菌,大大縮短檢驗所需的時間。

聚苯胺製備改良及其在防蝕應用研究

導電高分子在各面之應用非常廣泛,其中聚苯胺因價格便宜,製作簡便,使其應用潛力更為突出。聚苯胺在鐵系及非鐵系金屬之防蝕能力已被證實,但由於聚苯胺與金屬之附著力不良使其應用受到限制。本文以提高聚苯胺在有機溶劑中溶解度以達到和金屬有效附著增加其防蝕能力為主,而奈米粒子所具有的表面效應、小尺寸效應及宏觀量子隧道效應,可為研究目標之一。但由於高分子奈米微粒之製備仍屬有限,故仍在研究中。 \r The development and application of the conducting polymer poly-aniline is getting\r prosperous and popular. The capability of poly-aniline in corrosion protection has\r been proved. But due to the adhesion of poly-aniline on the metal is poor, the applications\r are restricted. In this paper, the authors utilized how advance the solubility of\r poly-aniline in organic solution to modify the adhesion of poly-aniline on the metal\r in order to improve the effect of the corrosion protection of poly-aniline in ferrous\r metal. And the nanoparticles have the special effects such as the surface effect,\r the small size effect and the macro-quantum channeling effect. It can be an object\r for research.

蜚腸知味-探討不同味覺刺激對美洲蟑螂口器及前腸活性的影響

前饋(feed-forward)是一種於生理反應發生之前,所進行的調節機制,為即將發生的生理作用進行準備。前人對於蟑螂消化道的前饋作用,大多著墨在酵素分泌的調節作用。本研究以美洲蟑螂作為實驗動物,觀察蟑螂消化道中前腸的組織型態,並以肌肉電位圖(electromyography, EMG)的記錄方式,探討探討味覺刺激對蟑螂嗉囊與砂囊肌肉活動的調節作用。我們發現蟑螂的消化道由橫紋肌所構成,有別於人類消化道主要由平滑肌所構成。由EMG的紀錄得知,餵食葡萄糖溶液時,可增加蟑螂嗉囊肌肉的放電幅度;而餵食味精(麩胺酸)溶液時,可增加砂囊肌肉放電幅度,推測葡萄糖與麩胺酸各可引發嗉囊與砂囊肌肉的收縮活動,皆屬於前饋機制的例子;若以清水清洗口器時,亦會引發前腸肌肉的放電行為,推測為清洗口器時引發吞嚥反射所致。

攀蜥,攀棲-由台北市內湖金面山區生態因子分析夜晚黃口攀蜥之停棲策略

For this research, the nocturnal perching habits of the lizard, Japalura Polygonata Xantbostona, were examined. Nighttime observations were made from July 2002 to March 2003 in the area along the mountain brook in the south valley of the King-Mien Mountain in Nei-Hu District. The study comprised a series of analysis with discussion of the lizard’s (Japalura Polygonata Xantbostona) perch based on the temperature of living environment and the manner of perch including the dissimilarity between male and female, adults and juvenile lizards in selecting their perch conditions. During the period of study 452 lizards were marked and examined. 163 were female, 168 were male, and 121 were young lizards. The study considered four particulars: (1) orientation, (2) angle, (3) manner of perch, and (4) height of the perch above ground. As for the orientation, most of the lizards chose to perch in an inward (towards the tree) and in an upward direction; the angle of perch was mainly within 1°~ 45° and slanted to 180°. Second, the manner of perch chosen by most of the lizards was holding the stem or trunk by arms. All four groups of lizards exhibited no difference in the orientation, angle and manner of perch. However, male lizards tended to perch at a greater height above ground than the female and juvenile lizards did. The study produced other findings as well: A tendency correlation curve was plotted showing that temperature related with the number of lizards taking perch, and from the curve the optimal temperature of the living environment was determined to be approximately within the range of 19° ~24°. Additionally, there was a relationship between temperature of living environment and the size of lizard and the number of lizards taking perch. A further positive relationship was observed between temperature and the height of perch above ground. Also, the study showed an apparent positive relationship between the temperature of sample living area and the snout-vent length(SVL) of the lizard. Finally, the Japalura Polygonata Xantbostona tended to take their nocturnal perches within a rather fixed home range. 本研究由2002 年7 月至2003 年3 月,於臺北市內湖區金面山南麓溪谷進行黃口攀蜥夜 晚停棲策略研究,以溫度和各項停棲行為進行來分析探討,包括黃口攀蜥的成幼蜥、雌雄蜥 停棲選擇上的差異。 研究期間,共標記到452 隻攀蜥,其中雌蜥163 隻、雄蜥168 隻、幼蜥121 隻。將停棲 的情況分為方向、角度、停棲型態、離地高度四項來分析,在方向上多以朝內、向上為主; 角度多以小角度的1°~45°及180°為主;在停棲型式多以環抱莖枝為主。進一步分析成幼蜥、 雌雄蜥不論在方向、角度、停棲型式的選擇上皆無差異。離地高度的部分則以成蜥及雄蜥的 停棲高度較高;以溫度分析黃口攀蜥的成幼蜥出現停棲隻次、停棲高度、出現停棲攀蜥體型 的相關性,溫度對出現停棲隻次可以做出趨勢相關曲線,估算攀蜥的停棲有一最適宜溫度範 圍約在19~24℃間;溫度與其停棲高度呈現正相關性;每次測得樣區溫度與出現停棲攀蜥平 均吻肛長有顯著的正相關。而黃口攀蜥夜晚婷棲時則會傾向於較固定的範圍內。

CryptoDefender - afast way to encrypt your files

1. Purpose of the research\r Nowadays, many encryption software are available to computer user. However, very few people use them which result in many cases of information and data leakage due mainly over the Internet. Most people use USB Flash Drive to store and carry confident files back home to work on. When the USB Drive is lost, the files stored are often leaked. To prevent this type of incident occurring, “CryptoDefender” is developed to enhance files protection and to change user’s habit in handling confidential information. \r 2. Procedures\r “CryptoDefender” is an add-in for common application software, e.g. Word, Excel, etc. It will appear as a new tab in the ribbon which provides the software an alternative for saving and opening a file. It protects the files in two ways: encryption and steganography. The data is first encrypted into cipher text as these encrypted data will be hidden in an image file to lower suspicion of readers. All of these procedures will be done by one click. For encrypt and decrypt, the user just needs to click the “Protect” and “Decrypt”. An extremely fast way to encrypt the file is “Quick Protect”. It will randomly choose an image from the image folder according to their file size. This function saves the time for choosing an image.\r 3. Data\r The method for steganography is using last two bit of R, last three bit of G and B to store the encrypted data. In 24-bit bitmap, RGB is represented the color of each pixel and each of them is 8-bit. The leftmost bit of each byte contains the highest value, and the right one contains the lowest value. Therefore, any change in the rightmost byte will only cause a minimal change in a byte value, and the color as well. 2-3-3 method is adopted to replace the pixels as encrypted data. It is used because it is in coordination with the program’s fluency. 2-3-3 is obtained so that 1 pixel will contain 1 byte of encrypted data. For R, the last two bit will be replaced by encrypted data. For G and B, the last 3 bit will be replaced by encrypted data. If the Bitmap size is larger than the encrypted data, random data will be replaced into the remaining pixels.\r 4. Conclusion \r “CryptoDefender” is user-friendly and efficient way to protect important and confidential digital files on most personal computers. This software will help to change the user’s habit in securing their information as to avoid data leakage even when they are accidentally lost.

奈米複合材料與空氣分子的愛恨情仇-探討奈米碳管對空氣滲透率之影響

本實驗使用聚醚亞醯胺溶液製備基本薄膜,由於玻璃態高分子薄膜過於緻密,一直是高分子薄膜在應用上的一大限制,為了在薄膜上製造缺陷,又不會使薄膜之選擇性降低,因此選擇將酸化之奈米碳管(孔徑10~20nm) 加至聚醚亞醯胺薄膜中。本實驗主要為探討添加不同濃度的酸化奈米碳管對聚醚亞醯胺薄膜的滲透率與選擇率的影響,藉由添加0.5 wt%、1 wt%、1.5 wt%、3 wt%、4 wt%等不同濃度的酸化奈米碳管至15 wt% 的聚醚亞醯胺溶液中,並製作薄膜,測試其基本性質與五種氣體(H2、CO2、O2、N2、CH4)的滲透率及不同空氣分子之間的選擇率。我們總共測試了三種薄膜的性質,分別是表面特性、熱穩定性及結晶型與層間距,薄膜的表面性質,能觀察到奈米碳管在薄膜中製造奈米孔隙結構,增加氣體滲透的孔道,能有效增加氣體的滲透率。增加奈米碳管的量,能有效升高第一階段熱裂解的溫度,雖然熱裂解在本實驗中沒有很大的差異,但是還是可以從熱重分析圖中推測不同量的奈米碳管會影響熱穩定性。在X 光繞射實驗中,添加奈米碳管的薄膜與純聚醚亞醯胺薄膜,在結晶相上都屬非結晶型薄膜,添加了奈米碳管的高分子複合薄膜的層間距明顯增大。在氣體滲透實驗中,我們比較了不同氣體或濃度不同的奈米複合薄膜的氣體滲透率,在不同氣體時,氣體的滲透率會隨著奈米碳管濃度增加有明顯的提升,五種氣體滲透率大致依照H2>CO2>O2>N2>CH4 這個趨勢增減。奈米碳管對1.5%增加到3%或4%的奈米複合薄膜滲透率的影響卻減小,由此可以推斷奈米碳管對空氣滲透率並非無限制的增加,在1.5%以後就漸漸趨近最大值。H2為14.89barrer,CO2 為9.51barrer,O2為6.34barrer,N2為6.48barrer, CH4 為3.75barrer 。本研究總共比較了三組氣體的選擇率,分別是CO2/CH4,O2/N2,H2/CH4,分離率最高的是H2/CH4 的,兩分子的粒徑大小差對分離率有極大影響,差愈大,其分離率也愈高。奈米碳管的量改變並不會使薄膜的氣體選擇率明顯增加或減少,但是加入太多奈米碳管其選擇率會變低。在五片薄膜中,1.5%的薄膜有最好的選擇率,奈米碳管的添加量超過1.5%選擇率就會開始下降。綜合滲透率及選擇率可以分析出,添加1.5%奈米碳管的高分子奈米複合薄膜有較高的滲透率,又不會降低選擇率,在利用上比其他濃度的奈米複合薄膜在有害氣體過濾及空氣的分離回收方面產生更好的效果。;This experiment uses Polyetherimide polymers solution to make basic membranes. Because glassy polymer membranes are too dense for gas permeations, it is one of the limitations in their applications. To increase gas permeability and maintain air selectivity, I made some nanogaps on the surface of the membranes by an acidification multi-wall carbon nanotubes (MWNTs, kinetic diameter 10~20nm) in the PEI membranes. We mainly want to find if it has some influence between the consistency of acidification MWNTs and gas permeability or selectivity. We mixed 0.5wt% 、1wt%、1.5wt%、3wt%、4wt% acidification Carbon nanotube in 15wt% PEI solution, made membranes and tested the character, five kinds of gas permeability (H2、CO2、O2、N2、CH4) and the selectivity between different gases. We have tested the three nature of membranes, including surface characteristic, TGA and XRD. We can see some nanogapes made by carbon nanotube in the membranes. It could availably increase gas permeability. Mixing more carbon nanotube in the membranes could increase the temperature of the first heat-decomposition. Though the heat-decomposition in this experiment didn’t change a lot, we could say that different percent nanotube would affect the membranes’ heat-decomposition. By the experiment of XRD, the membranes with carbon nanotube and the pure PEI membranes attach to amorphous membranes. Nanocomposite’s de-spacing is bigger than pure membranes. In the experiment of air permeability, we compared different kinds of gas or different percent carbon nanotube of nanocomposite if they have some change of permeability. The conclusion is that air permeability increase as the quantity of nanotube increase. The five kinds of permeability the direction:H2>CO2>O2>N2>CH4.The influence of permeability will decrease when the quantity of carbon nanotube increase from 1.5% to 3% or 4%. We can get the conclusion that the increment of gas permeability isn’t limitary. It drifts towards maximal about 1.5%. H2 is 14.89barrer. CO2 is 9.51barrer. O2 is 6.34barrer. N2 is 6.48barrer. CH4 is 3.75 barrer.This experiment totally compared three groups of air selectivity. They ’re CO2/CH4, O2/N2 and H2/CH4. The maximum of selectivity is H2/CH4. The difference of kinetic diameter affects air selectivity a lot. The quantity of nanotube doesn’t associate with the air selectivity, but mixing too much nanotube will decrease air selectivity. The 1.5% nanocomposite has the highest selectivity. If the consistency of the membranes is higher than 1.5%, the air selectivity will decrease. Depend on the gas permeability and the air selectivity, the 1.5% nanocomposite has higher permeability and constant air selectivity. That shows the 1.5% nanocomposite has a better effect on air selectivity and recycling.