全國中小學科展

未得獎作品

挑戰溶液的電中性~「帶電溶液的研究」

利用范式起電器將靜電導入蒸餾水、甘油、苯、環己烷、乙醇、正丙醇、正戊醇,以及HCl(aq)、NaCl(aq)、CuSO4(aq)……等不同溶液中,我們發現:非電解質溶液可以藉由極性分子的媒合作用"貯存”電子,而其中H2O效果最好,即水合電子是可以穩定存在的!但在水中若添加HCl、NaCl等電解質會提高容易導電性,以致於無貯存電子的效果。我們也發現苯雖不是極性分子,但因具有π共振系統,也能有效貯存電子。另外,從引入密度泛函數理論結合類導體可極化連續模型加以計算的結果,也能發現極性分子容易的溶劑電子親核能比非極性分子容易來的大,與實驗結果吻合。By using a Van de Graff Generator to put electrons into various solutions or solvents (such as water, alcohol, benzene, propyl alcohol, solutions of sodium chloride, etc.), we find out that nonelectrolytes can "store" electrons through hydration of polar molecules. And water has the best ability of keeping electrons among others. In other words, hydrated electrons can exist stably. However, if we add electrolyte into solvent, the solution won't store electrons because of its increasing electric conductivity. The experiment also shows that benzene can keep electrons though it is a nonpolar molecules. We infer that it is the " π resonance system " which contributes to its high ability of electron storage. In addition, by introducing the calculations of CPCM (Conductor-Like Polarizable Continuum Model), we find out that the electron affinity of polar solutions are stronger than those of nonpolar solutions. The computed results are in agreement with our experiment.

基因突變對線蟲(Caenorhabdits elegans)之神經系統退化變異株的搜尋以及對其性??

This research is mainly in observation with Caenorhabditis elegans ’s genetic mutation caused via nervous system abnormal character. In the study, I the sample have been cultivated purified and add some chemical material EMS to speed up C.elegans mutation. Then based on the character to further analysis what causeof gene deal with mutation and observe the effects in heredity. The research has two stages, on the first stage of study the mainly target is to both search and purify the mutation of C.elegans. The second stage is based on the exploration of mutation’s searching andpurifying. Because the certain mutation bodies aren’t easy to find out, the project is still on progress at the beginning of second stage, and we conclude some heredity special cases in preliminary of study. 這個實驗主要是觀察並針對線蟲因為基因的突變所產生的神經系統異常的變異性狀,在實驗中我先將樣品線蟲培養並純化至一定數量,並加入適當藥劑EMS造成其突變,經篩選並分析此性狀,進而找出造成其突變之基因,以及觀察此性狀對遺傳表現所造成的影響。 該計畫分成兩階段,第一階段的實驗重點是在突變株的搜尋以及純化上,第二階段則是在突變基因的探討上,由於特定突變株的搜尋並非容易,所以目前計畫只進展至第二階段的遺傳實驗初期,對於其遺傳特徵與突變形式上已有了初步的分析,但尚未定位出該基因的位置。

南國田字草的型態生理與睡眠運動之研究

Marsilea quadrifolia, an aquatic perennial rhizomatous fern, is widespread on wetlands in Taiwan. A normal fern frond has the clusters of spore capsules on the back, yet Marsilea quadrifolia reproduces clusters at petiole base from sporocarps which are axillary, pedicellate, ovate and hairy; both microsporangia and megasporangia can be found in sporocarps. It is highly polymorphic. The sterile fronds are erect when growing in mud, and floating in water, and they produce leaflets in the shape of four-leaf clovers. Mature leaves are divided into water leaves and terrestrial leaves according to living environments. Water leaves are divided into submerged leaves, floating leaves, and emergent leaves. These four kinds of leaves have obvious differences in stoma density. The submerged leaves have the least starch which means they have the minimum photosynthetic efficiency. The flexible leafstalks allow the plants to adapt to small changes in water level, while keeping their leaves on the water surface to access light and carbon dioxide. Thus, heterophylly may be seen as an adaptive mechanism which is sensitive to some environmental parameters and that responds accordingly to maximize the capability for survival. The terrestrial leaves have periodic sleep movement according to the alternate changes of day and night. The biggest opening angle is related to a definite leaf closing time cycle. Light interference during the dark period, continuous lighting, or the reversing of day and night all interfere the opening time and speed of them.南國田字草是一種浮葉性、多年生水生蕨類,匍匐莖細長橫臥在水中泥土或濕地裡,葉四枚對生於葉柄頂端,依生長環境不同,可分為水生葉及陸生葉,水生葉又分沉水葉、浮水葉及挺水葉三種。孢子囊群聚集特化成堅硬的孢子囊果,長於葉柄基部,孢子有大、小孢子兩型。四種異型葉在內部構造、氣孔分布密度上皆有相當的差異,以適應環境的變化,葉片澱粉含量以沉水葉最少。南國田字草陸生葉隨著晝夜交替,具有週期性的睡眠運動,每天葉片開啟的最大角度和閉合時間有一定的時間範圍。黑暗期受光照干擾或連續照光、日夜顛倒,皆影響葉片的開閉時間與速率。

雷射光的研究

這份報告的主題是藉由實驗,來探討雷射光的性質及它的應用,並實際製作利用雷射光原理的小器具。1.證明雷射光是否為單色光:先將雷射光射入不同顏色的玻璃紙,利用光無法穿透不同顏色玻璃紙的性質,以及將雷射光照射三稜鏡,觀察其反射的光線,藉此來證明雷射光是否為單色光。2.雷射光的直進性質:利用彎管或其他不透光物品將光線阻擋,觀察其是否能穿透物品,並且用不透光物質,使我們能夠看出雷射光的軌跡,來證明雷射光的直進性質。3.雷射光的折射與反射:將雷射光射入不同的物質中,觀察其折射角度,來得知雷射光在不同介質中的傳播速率不同,也觀察其是否有反射的現象。4.雷射光的應用:研究運用雷射光製成的物品,如雷射印表機、光碟機等等,並了解其製作原理。5.自行研製雷射小器具:利用雷射光的原理,來製作簡單而獨特、有效率的小器具。The topic of this report is to study the quality and applications of laser by experiments, and actually make a tool by using the principles of laser.1.Prove if laser is a one-color light: By lasing laser through a triangular prism, observe the light it reflected to prove that laser is a one-color light.2.The quality of in-line approach: By using tubes or other lightproof items to block out the light to observe if it can penetrate things, and also let us see the trace of laser to proof the quality of in-line approach.3.The refraction and reflection of laser: Study the differences of refracting angles by lasing laser into different items, to know the speed of laser in different mediums, and also observe if it will have any reflections.4.The applications of laser: Understand how laser products are made by studying them, like laser printers and CD players. 5.DIY laser tools: Make simple but unique and efficient tools by using the principles of laser.

以二極體汲發之 Nd:YAG 雷射之探討

Nd-YAG Laser 是目前最常被用來當作Pumping Source(汲發光源),較早期是使用discharge lamppumping,但是閃光燈的發光頻率並非完全落在Nd-YAG 晶體的吸收帶上,因此大量的能量轉變為熱能,十分的浪費能源,且增加冷卻系統的負荷。因為discharge lamp pumping 是一種氣體放電的過程,每次放電的時間和能量都有很大的不穩定性。所以高效率、高穩定性的Laserdiode 便成為pumping source 的另一種選擇。在此實用價值下,便決心以一組Laserdiode Pumped Nd-YAG Laser的套件,使用AlGaAs Laserdiode 作為pumping source,來汲發Nd-YAG 晶體,所有物件被固定在同一個rail(軌道)上,從對光到汲發晶體(增益介質Nd-YAG 晶體),到產生1,064nm 的紅外光雷射,及其倍頻532nm 的綠光雷射,正可作為一完整的雷射訓練過程。

利用雷射光實驗研究溶液的折射率梯度

溶液和溶劑置於同一容器中,當溶質向上擴散時,會形成濃度梯度及\r 折射率梯度dn/dy,且dn/dy 對高度y 的關係圖會呈現隨著高度改變的現\r 象。\r 半徑r 的D形容器,下方置溶液,上方置溶劑,以雷射光照射容器的\r 平面部份時,雷射光沿著法線出射,受折射率梯度的作用而向下偏Ζ距\r 離,a 為容器至屏的距離,得到dn/dy=Z/ar 的關係式;改變雷射光的高\r 度y 可得dn/dy 圖。\r 以硫代硫酸那作實驗,其dn/dy-y 圖為以原始界面為對稱軸,因其擴\r 散係數不隨濃度改變;甘游水溶液的dn/dy-y 圖呈現不對稱,圖形的極\r 大值往甘油方偏,主要係因為甘油的擴散係數隨濃度的增大而減少。\r 我們成功第把不同時間對同一溶液的實驗結果予以模型化,得到的\r dn/dy-y 曲線隨時間改變,並發現該曲線所涵蓋的面積為定值。\r \r The mixing in a vertical column between a pure liquid and a solution produced a concentration gradient, which in turn produced the refractive index gradient. As the solute particles diffused upward into the pure liquid, the gradient was generated by the varying solute concentration. The plot of the refractive index gradient versus vertical position y (dn/dy vs y) is found to be varied with time. A D-shape container of radius r is partly filled with denser solution, and partly filled with solvent which is on the top of solution. When laser beam enters perpendicularly to the flat surface of the container, the outgoing beam strikes the container at normal incidence, and deflected down a vertical distance Z by the refractive index gradient. We can get dn/dy=Z/ar, where a is the distance between the container and the screen,. By changing the vertical position (y) of laser beam, we can get the plot of dn/dy vs y. For a sodium thiosulfate-water solution, the trace of dn/dy vs y is symmetric with respect to the position of original boundary. Since the diffusion coefficient of sodium thiosulfate is independent of concentration. For the trace of dn/dy vs y of a glycerol-water solution, it will no longer be symmetric. A skewed curve which reaches its maximum position is displaced to the glycerol side, because the diffusion coefficient of glycerol is decreased with concentration. We have successfully modeled the time-dependent experimental gradient curves on the same solution. The trace of dn/dy vs. y at different time is found to keep the area constant.

數列生成遞迴

這個題目是源自2003年的TRML思考賽的題目,原題目並不難,它只有用到簡單的排列方法,主要是討論 an 、bn 兩種數字的排列,其中 an 為滿足下列所有條件之N位數A的個數。 I. A中每一個數字為1或2 II. A中至少有相鄰的兩數字是1 而 bn 表示滿足下列所有條件的N位數B的個數 I. B中每一個數字為0或1 II. B中至少有相鄰的兩數字是1 以及探討an 、bn 與費氏數列cn之關係,其中 cn = cn-1 + cn-2 ,n≧3 ,c1=1, c2=2 。 其中 an 如果改成考慮為一數列,其值不變;而 bn 如果改為數列,那麼就不需要考慮0不能為首位數字的情況。如此,讓人聯想到一個用生成函數解的題目「一個N項數列,其中每一項只能是0或1或2,其中0和2永不能相鄰,求這個數列個數的一般式。」,因此,我們嘗試將這個題目改變它的要求繼續做下去,發現其中有某些規則,例如:不只是原來的11相鄰,甚至是排列其它種方式,都可能從其遞迴式看出它排列的意義,甚至這種排列數是可以用遞迴式求出來的。這提供了我們另一種求數字排列的方法,也是我們覺得有趣的地方。 在過程中我們初步得到以下結論: This solution is according to power contest of 2003 TRML. It is composed of two number arrangements, an , bn . First, suppose an is the total number conforming to the following rules. I. Each number is 1 or 2 in A. II. There is a couple of (11) in A at least. Then, suppose bn is the total number conforming to the following conditions. I. Each number is 0 or 1 in B. II. There is a couple of (11) in B at least. Furthermore , we give the thought to the relation among an , bn ,and cn (Fibonacci Sequence). By the way, if an is changed to a sequence, and the result is the same. But if bn is to arrange number, we have to give thought to the fact that the first number can’t be zero. If it is a sequence, we don’t have to consider it. The problem belongs to combinatorics. After we do this problem, we find not only original question but also other permutation can be understood by its formula. The problem provides us with other means to solve permutation and combination question. Then, we get the conclusion as follows:

金奈米粒子的合成與其光譜特性

當世界各國正全力朝奈米科技發展,而奈米微粒對環境及人類健康影響與否未明朗之際,有關奈米微粒對人類健康影響之探討是刻不容緩之事。本研究的近程目標是合成金奈米粒子,遠程目標是擬探討金奈米粒子的生物毒性。此份研究主要是描述金奈米粒子的最大表面電漿吸收光譜特性及其最大吸收波長,而金奈米粒子的合成是利用四氯金酸( HAuCl4 )與還原劑—硼氫化鈉( NaBH4 )、聯胺水合物( N2H5OH )或檸檬酸鈉在陽離子界面活性劑的溶液( CH 3(CH2)15N+(CH3)3Br– ,溴化十六烷基三甲基銨,CTAB ) 當保護劑中,利用氧化還原方法直接生成金奈米粒子,並探討四氯金酸的濃度、還原劑的濃度、界面活性劑的濃度及反應溫度,對金奈米粒子生成之影響,另外也探討金奈米粒子的穩定性。有關金奈米粒子的光譜特性則利用UV/Vis 光譜儀測試。研究結果發現在相同的條件下,利用冰浴,以NaBH4 當還原劑所合成出的金奈米粒子之平均粒徑為11.70 nm ,而以N2H5OH 當還原劑所合成出的金奈米粒子之平均粒徑為20.25 nm, 有關金奈米粒子之結構及大小藉由穿透式電子顯微鏡( TEM ) 拍攝出的影像得以驗證。;This study mainly focused on the properties of the maximum surface plasmon absorption of gold nanoparticles and their wavelengths. The synthesis of gold nanoparticles made use of HAuCl4 aqueous solution and reducing agent, through the oxidation reduction method, with reductant, sodium borohydride ( NaBH4 ), hydrazine ( N2H5OH ) or sodium citrate solution in the presence of the cetytrimethylammonium bomide ( C19H42BrN,CTAB ) aqueous solution as protecting agent. The influence of concentration of HAuCl4, reductant, surfactant, and temperature on the synthesis of gold nanoparticles were explored. In addition, the stability of the gold nanoparticles was also explored. Measurements of spectral properties of gold nanoparticles were done by UV/Vis spectrometer.When NaBH4 was used as a reductant, the average diameter of gold nanoparticles was 11.70 nm. When N2H5OH was used as a reductant, the average diameter of the synthesized gold nanoparticles was 20.25 nm. The structures and sizes could be identified by the transmission of electron micrograph (TEM) images.

長期處理兒茶素對無機砷與氯化鎘之遺傳毒性

重金屬對人體傷害的無遠弗屆-人人皆知,根據流行病學的研究指出,長期處\r 在重金屬含量過高之地區,易造成生理病變。比方說,長期生活在砷含量高的環境\r 中,易導致肝臟、周邊血管及神經系的損害,各種癌症的發生機率也大為提高;長\r 期處在含量過高的鎘環境中,易引起不正常的鈣代謝﹐產生骨質疏鬆症、軟骨症、\r 糖尿、胺基尿酸、尿蛋白、貧血、和肝功能異常的症狀;而目前坊間所看到各類茶\r 品中含有的兒茶素則被發現具有抗氧化、抗突變及清除自由基等功能。故本實驗以\r 人類胃癌細胞(SC-M1)為材料,以微核(micronuclei)偵測技術觀察細胞長期處理兒茶\r 素((-)-epigallocatechin-3-gallate, EGCG)後,對於亞砷酸鈉(sodium arsenite, NaAsO?)\r 及氯化鎘(cadmium chloride, CdCl?)所造成的細胞遺傳毒性有何影響。另一方面則利\r 用SRB 分析法測量細胞存活率,探討長期處理兒茶素後,亞砷酸鈉及氯化鎘對於細\r 胞的毒殺情況是否改變。實驗結果顯示細胞長期處理兒茶素不會造成微核的增加,\r 但是卻會增加細胞的存活率;單獨處理亞砷酸鈉和氯化鎘則都會使細胞中微核明顯\r 的增加,且會降低細胞的存活率;而長期處理兒茶素的細胞對亞砷酸鈉所誘發的微\r 核有抑制作用且會增加細胞對於亞砷酸鈉的耐受度,長期處理兒茶素無法抑制氯化\r 鎘所誘發的微核與細胞毒性。\r \r \r It is well documented that exposure to heavy metals could cause seriously adverse\r effects to humans. Epidemiological evidence has shown that illness is frequently\r observed in residents living long-term in heavy metal contaminated area. For example,\r long-term exposure of arsenic was associated with increased incidences of liver diseases,\r peripheral vascular and neurological diseases, as well as cancers. And long-term exposed\r to cadmium may lead to abnormal metabolism of calcium, osteoporosis, osteomalacia,\r glucouria, aminoaciduria, proteinuria, anemia and abnormal liver function. Recently,\r numerous reports have shown that (-)-epigallocatechin-3-gallate (EGCG), the major\r polyphenol from green tea, have ability to anti-oxidative stress and anti-mutagenesis. In\r this report, we investigated the effects of EGCG long-term exposure in sodium arsenite\r and cadmium chloride induces chromosomal damages and cytotoxicity in a gastric cancer\r cell line, SC-M1. Our present results demonstrated cells long-term exposure to EGCG did\r not induce micronuclei (MN) formation but induce the growth rate. Sodium arsenite or\r cadmium chloride alone significantly induced MN formation and cytotoxicity in cells\r without long-term EGCG exposure. However, long-term treatment of SC-M1 cells with\r EGCG significantly reduced MN formation and protects the cells from cytotoxicity\r induced by arsenite. Long-term exposure of EGCG had no effect on MN induction and\r cell survival in cadmium-treated SC-M1 cells.

為「世紀之毒」找解藥!- 探討以Pseudomonas mendocina 菌株降解污染土壤中戴奧?

本研究採自中石化安順廠戴奧辛污染場址之土壤,篩選出一株純 菌微生物(Pseudomonas mendocina NSYSU) , 其含有PCDD/Fs (Polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans, PCDD/Fs)土壤於實驗室進行微生物降解試驗,結果顯示約21 天即有 明顯降解結果;本研究同時觀察到該微生物能在汞濃度達50 ppm 之 戴奧辛土壤中,仍具有相當程度之耐受度,並進一步降解戴奧辛化合 物。 我更以標準品探討菌種對於戴奧辛類化合物(Dioxin like congener) 之降解效果,成功地發現這株菌種不僅對於PCDD/Fs 有降 解能力,對於戴奧辛類化合物也有明顯之降解效果。 由研究結果,明顯看出P. mendocina 菌株為「世紀之毒」找到了 解藥,開發出以生物復育改善污染環境的一種新方法。A dioxin-degrading bacterial strain Pseudomonas mendocina NSYSU was isolated from dioxin contaminated soil by selective enrichment techniques. In our previous study, P. mendocina NSYSU was found to be able to use pentachlorophenol (PCP) as its sole carbon source and energy source and was capable of completely degrading this compound. Moreover, P. mendocina NSYSU was also able to mineralize a high concentration of PCP up to 150 mg/L. In this study, P. mendocina NSYSU was investigated for its ability to degrade polychlorinated dibenzofurans (PCDFs) and polychlorinated dibenzo-p-dioxins (PCDDs). Results show that P. mendocina NSYSU could grow well in media containing both PCDFs and PCDDs, and was able to degrade both compounds efficiently. In this study, isotope dilution method and a high resolution gas chromatography-mass spectrometry (HRGC/HRMS) technique were applied for the analyses of PCDFs and PCDDs. Investigation results reveal that significant biodegradation of octachlorinated dibenzo-p-dioxin (OCDD) and octachlorinated dibenzofuran (OCDF) by treating with P. mendocina NSYSU resting cells was observed. The results also indicate that this bacterial strain is able to biodegrade OCDD and OCDF effectively under anoxic conditions due to its facultative anaerobic character. No accumulation of inhibitory toxic byproducts was found in this study. These findings suggest that in situ or on-site bioremediation of dioxin-contaminated soils by using indigenous microorganisms or inoculated P. mendocina NSYSU strain would be a feasible technology for field application.