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臺灣

共鳴管共振頻率誤差探討

於共鳴管實驗中,我們發現管口與聲源間距離會影響管子的共振頻率,距離愈遠、共振頻率愈高,最後趨於一穩定值。本研究探討此現象及相關變因,提出球面波的共振頻率公式,並證明球面波的共振頻率、及共振頻率隨管口與聲源間距離改變而變化的幅度,與管長、管徑及管口與聲源間距離相關。同時,對於狹縫繞射實驗,透過本研究推導之球面波共振頻率公式,可利用實驗測得之共振頻率求得繞射波的假想波源位置。而管子共振時,駐波僅存在於管內,其腹點位置必位於管口附近(受管口修正影響)而非聲源處。因此,進行共鳴管實驗時,不可將音叉擺放位置視為波腹位置。

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.

『亮』出色彩-PLED 的製作

利用化學合成法合成出聚苯胺及MEH-PPV,經過一連串的製程作出高分子\r 發光二極體(PLED),再用I-V 儀量測。實驗中以聚苯胺及MEH-PPV 的薄膜厚\r 度為變因,進行實驗。設定I-V 的電壓值為10V,量測樣品通路上的電流。一開\r 始電壓在跑時,量到的電流都為0A,所得到的圖形為一水平直線;當電壓到達\r 一個值時會向上爬升,但爬到一個階段後圖形呈現鉛直掉落至電流為0A,圖形\r 又恢復成水平直線。過程中看到了薄膜厚度對樣品確實有影響,又鋁電極的厚度\r 不能承受過大的電壓,電壓一大,樣品馬上就燒壞了。\r Abstract:\r Using Chemiccal polymerize PANI and MEH-PPV make through a series\r Polymer light emitting diode(PLED)Produce.then using I-V meter surveies. PANI\r and MEH-PPV change of thick proces.Experiment design I-V volt for meter\r conduction of current of sample .The voltage moving.First meter current is obtaining\r the figure is horizontal when voltage increase to a special value , but increase a while ,\r the current will fall down to zero volt. Figure will go to horizontal that sample will\r change .Thick is different,and aluminum cathode can not suffer too much\r voltage .otherwise will burn.

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:

由嘉義地區的氣象資料來探討二十四節氣與聖嬰現象

二十四節氣是中國古代對氣象觀測的智慧結晶,由於近幾年來聖\r 嬰與反聖嬰現象的影響,在透過嘉義氣象觀測站的協助之下,利用\r Excel 進行簡易的雨量和氣溫統計,並配合中央氣象局發布的環流型\r 態和農業災害,來探討二十四節氣在嘉義地區的適用性。\r 以陽曆來區分節氣,每年會誤差6 小時,加上四年一閏,剛好彌\r 補差距,農曆則需19 年。至於聖嬰現象對嘉義地區則呈現涼夏和暖\r 冬,但在反聖嬰現象中則變為加強四季之特性,即是熱夏與寒冬。兩\r 者都造成雨量集中夏秋兩季,形成冬春乾旱。至於二十四節氣則是以\r 夏、秋的氣溫和雨量相關的諺語較適合嘉義地區。\r Abstract\r The 24 Solar Terms, is the achievement of weather observation from\r ancient China. Because of the effects from El Nina and La Nina these\r years, we proceed simple statistics of rainfall and temperature by using\r Excel and the assistance from Chia-yi Weather Station. We adopt the\r Circulation Type and the damage of agriculture from Central Weather\r Bureau, to discuss if the 24 Solar Terms for in Chia-yi area.\r To divide the 24 Solar Terms according to the solar calendar, there’ll\r be a six –hour gap every year. The gap could be made up every four years.\r But with the lunar calendar, it takes nineteen years to offset. The El Nina\r shows cool summer and warm winter in Chia-yi area, but the La Nina\r emphasizes the characteristics of the four seasons. It shows hot summer\r and cold winter. Both of them rain mostly in summer and fall, and cause\r the drought in winter and spring. The saying of the 24 Solar Terms is\r suitable for the temperature and the rainfall during summer and fall in\r Chia-yi area.

什麼尚「氫」--談燃料電池之放氫探討

氫是一種非常理想的能源。不僅效率極高,且不會造成環境污染。空氣中的含量極少,常用的電解水方式又效果不彰。我們利用Ag、Ru、Cu 、C-CuPu、C 等數種電極,與H2SO4、 H3PO4 、HNO3 電解液,分別在10V 雙電極與-0.8V 三電極下做電解水實驗,研究何種電極與何種電解液能得到最多的氫氣量。在低電壓下找出最好的電極,液與太陽能電池結合,成為電池中的一部份,讓發電效果更好,以利未來燃料電池H is a kind of great power.It is not only effective,but also no environment pollution .Owing to the H in the air is very little,so it is not easy to take .Addition to,we often to take it by electro liquid,but the electrolysis effect is not ideal. Except Ag、Ru、Cu、C-CuPt、C and so on ,in theH2SO4、 H3PO4 、HNO3 electro liquid,we have a experiment in the 10V dual electrode and -0.8V triple electrode to study which electrode and which electro liquid to get the most of H.Under the low voltage,we can fund the best electrode.It is easy to bind with solar energy battery,andit can be a part of battery.Besides, it makes the generator effect better,and it is convenient to make the fuel cell commercialize in the future.

昆蟲也會大小眼!?

本研究目的主要在瞭解昆蟲的複眼(compound eyes)結構,比較晝行性與夜行性昆蟲複眼之差異,探討其視覺遠近和複眼結構的關連,及進一步觀察其對不同波長光源反應的差異。本實驗使用反射式及倒立式顯微鏡來觀察複眼及其小眼的結構,及觀察其成像情形,並使用攝影式接觸分析儀與放大管來探討視覺遠近和小眼表面曲率之關連,另外在暗室利用不同波長的光源照射蝴蝶以觀察其反應。實驗結果顯示複眼是由數千至數萬個小眼組成,小眼表面曲率半徑隨選用物種在25.3μm 至117.6μm 之間,蜻蜓複眼上半部和下半部小眼曲率半徑分別為30.6μm、117.6μm,印證了蜻蜓複眼上看遠下看近的說法,也發現蝦子小眼是正方形,其他實驗物種則皆為六邊形,而蝴蝶對光的反應程度則是隨波長漸增而遞減。The main purpose of this study is to understand the structure of the compound eye of insects, to compare the difference between the diurnal insect’s compound eye (apposition eye) and that of the nocturnal insect (superposition eye), to explore the relationship between the vision and the structure of the compound eye, and to observe the eye’s reaction to the different light wave length. In this study, a microscope (OLYMPUS BX51M) and an inverted microscope (OLYMPUS 1X71) were used to observe the structure of the compound eye and its ommatidia, as well as the resulting image. A contact angle measuring instrument (Dataphyscis OCA 20) and a microscope (Mitutoyo NAVITAR) were used to determine the connection between the vision distance and the facet curvature of ommatidia. The butterfly’s reaction to the light source with different wave length was also observed in a darkroom. It was observed that the compound eye of insects is composed of more than a thousand ommatidia. Among the subject insects, the facet curvature radius of their ommatidia ranged from 25.3μm to 117.6μm. The radius of the top and bottom half of a dragonfly is 30.6μm and 117.6μm. It confirms a scientific finding that dragonfly’s top compound eye focuses farther than the bottom half. The facet of each ommatidium observed is hexagonal in insects compared with the square shape found in the eye structure of shrimp. Regarding the reaction to light of the butterfly eye; the reaction decreased when the light wave length increased.

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.

蝸牛球

蝸牛球是一種科學教具,以壓克力圓柱容器為主體,在容器中加入黏滯液體及重物。在滾動時利用黏滯液體的摩擦力將容器中的重物帶到相對容器重心的後方,使重物的重力對容器產生相對於滾動方向相反的力矩,造成容器減速的現象,實驗裝置如圖1、圖2所示。本實驗想探討黏滯液體的體積、軌道傾斜角度與金屬圓柱材質、體積及重量等變因對滾動變化的影響。