全國中小學科展

2003年

電解與磁場的秘密.

金屬離子在磁場中的流動速率會略有改變,尤其是在強磁場中時,其影響更是顯著,即 【MHD 磁流動效應】,造成整體電解液中離子的流動,此流動比擴散速率佔優勢。再利用「磁 矩」具有向量性質,探討不同金屬離子(Na+、K+、Fe3+、Al3+、Mg2+)及MnO4 -在磁場角度 相同但強度不同的情況下;及磁場角度不同但強度相同的情況下,對電解速率的影響。 經實驗發現有以下結論: 一、由法拉第電解第一定律出發,加以實驗數據分析,可推導出一關係式: 電解速率Rρ= k ×∫〈∣H 向量∣×∣cosθ∣〉×∣E 向量∣ (k 單位:g / C˙weber˙s) 二、電解效率隨價數增高而增快。 三、較強的電解質,其對磁場的感應也越大,如果就同一族而言,往 下其活性越強,對磁場的感應也越強。 The flowing rate of Metal ion changes slightly in magnetic field. This influence is especially remarkable while the magnetic force is very strong, that’s【MHD (magneto Hydrodynamic Effect ), which gives rise to ionic flowing all over the electrolyte. This flowing rate is superior to expanding rate. Further, basing on the magnetic torque ’s vector trait, this research studies how electrolysis velocity affects different metal ions (Na+、K+、Fe3+、Al3+、Mg2+) and MnO4 - under following situations: Some results are found through the experiment. 1. Begin with Farad Electrolysis First Law, and take the experimental analysis into account, then a relative formula comes out as bellow. Electrolysis Rate Rρ= k ×∫〈∣H∣×∣cosθ∣〉×∣E∣ (k:g / C˙weber˙s) 2. Electrolysis efficiency accelerates by the increasing price amount. 3. Active electrolytes get strong response to the magnetic field. For the same group, the more active the electrolytes are, the stronger it responds to magnetic filed.

磁性流体薄膜在水平磁場下結構型態之研究

本研究探討不同的控制變因,對磁性流體薄膜在水平磁場下有序結構的影響。我們發現,外加水平磁場於磁流體薄膜時,會形成一維有序磁鍊排列,磁鍊間距除會隨著磁場增強而變小外,另外其條件值如磁場強度、流體濃度、磁增率、薄膜寬度及厚度等也影響磁鍊間距。其中磁增率及磁流體濃度增加會使磁鍊間距變小,而凹槽寬度及薄膜厚度增加會使磁鍊間距變大等現象。至於其形成磁鍊的物理作用,我們假設薄膜有三種能量交互作用,即(1)磁鍊與外加磁場間的磁能UdH。(2)兩條同方向磁化的磁鍊間相互排斥所造成的磁能Udd。(3)熱能Uther等。藉由系統能量Udh+Udd+Uther最小化,我們導出了磁鍊間距和外加磁場之間理論上的關係,並比較實驗結果確實具有相當的一致性。因這些有序結構會引發許多的光學性質,將來這些特殊的光學性質預料應可製成可調式光柵、光開關及顯示器等光電元件,使磁流體在奈米世界及光電領域裡扮演重要角色。We investigate experimentally the structure of the magnetic chains formed in the magnetic fluid thin film under the influence of the external magnetic field parallel to the film surface. A one-dimensional ordered structure forced by magnetic chains can be obtain in the magnetic fluid film. It is worth noting that the ordered structure can be manipulated by changing the control parameters such as the magnetic field, concentration of magnetic fluid, the thickness of the film, the width of the film, and the dH/dt. On the other hand, the physical mechanism of forming the ordered structure can be also studied theoretically. These magnetic chains are regarded as magnetic dipoles and three possible interactions are condisered for the energy of the system: the attracting potential energy between the magnetic chain and H(denoted by UdH),the repulsive potential energy between two magnetic chains with parallel magnetizations(denoted by Udd), and the thermal energy Uther. The relationship between the chain distance △x and the applied magnetic field H was derived by minimizing the total energy of the system with respect to the chain distance. The experimental data is consistent with the theoretical results.

『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.

Keeping Cool

My aim was to test the effectiveness of coolboxes under different\r conditions, to use this information to do comparisons using commercially\r available coolboxes and finally to build an effective and cheaper coolbox\r appropriate to Namibia\r The general method used to compare different coolboxes involved\r measuring the rate at which ice melted inside the cool boxes under\r different conditions.

日光燈下的二道彩虹

某次於學校的科學表演中,見到黑白陀螺在旋轉後會產生顏色的\r 變化,使人印象深刻。文獻上記載此類陀螺稱為“Prevost”圓盤,\r 其色彩產生的原因一般被認為是人眼產生之錯覺。不過究竟為何會有\r 這種錯覺,總令人相當納悶。於是我們請教了老師,不僅做了實驗,\r 也用像機拍攝下來分析,不過令我們感到奇怪的是:如果是眼睛產生\r 的錯覺,又為何能拍出顏色?甚至,在研究的過程中我們意外的觀察到鏤空圓盤內的色塊裡,\r 尚有像水波「波紋」般的條紋出現。這個現象十分奇特,於是我們設\r 計了一系列的實驗去探討這些現象,開始了這次的研究。在研究過程中我們遇到相當大的困難,所幸同伴的程式設計技術\r 卓越。為了實驗也撰寫了許多套色彩分析程式,使得實驗更能得心應\r 手。而我是負責實驗儀器的架設及實驗操作,希望能以分工合作的方\r 式,來完成這次的研究。

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.

間歇泉的研究

間歇泉是一種十分奇特的地質景觀,地下水受到火成岩入侵所帶來的穩定熱源加熱,產生水蒸氣,利用水蒸氣形成的空氣柱壓力推動水由地底噴發出地表,也因為熱源穩定使得噴發時間差接近一定值,形成所謂的「週期性」。而根據實驗結果發現,管壁較薄的管子,在噴發之後,會使管中殘餘的水稍作降溫,加上補充的冷水使系統降溫;管長愈長時,蓄水槽中的水量較多,提高溫度所需的時間也較長,而延長了噴發的週期,最後歸納出間歇泉形成及存在的三個主要條件:(1)穩定的熱源;(2)細長的孔道;(3)豐沛的地下水。 The geyser is a very amazing sort of geologic scenery. Its principle is that the heat source of invasive volcanic rock heats the underground water to produce steam that results an air-columnar with a large pressure to erupt through the underground on the surface. Because of the steady supply of heat source, the period between eruptions is closed to a constant called “periodicity.” According to the result of the experiments, the tube that have thin wall can lower the remaining water’s temperature a little and the cold water’s supply can also lower the plumbing system’s temperature after eruption. Besides, the water in the longer tube needs more time to higher its temperature to protract the period because it have more water in its reservoir. Eventually, there are 3 essential conditions of the geysers’ existence concluded: (1) steady supply of heat; (2) a thin and long standpipe; (3) abundant underground water.

3D立體建構模擬之研究

現在的市面上,四處充斥著各式各樣的電玩或是3D立體動畫,但是在呈現動畫的\r 時候,依然存在著很多地方的不足,與狀況表現上的矛盾情形!於是令我興起:一個普\r 通的高中學生,是否也有機會運用所學的知識,創造出自己的虛擬實境?\r 我嘗試地寫出各種物體架構的函數,再對這函數圖形所呈現出的立體加工處理,使\r 它能自由的運動,甚至使它能多采多姿就有如我們在現實生活中所看見的一般,有著自\r 己的花紋與圖案!\r 期望在架構完整之後,有一天,我們這些學生可以不再被那些軟體公司牽著走,花\r 大把的錢買電腦動畫中種種的不合理,而可以自己擁有自己的3D 世界!!

Why cannot we see rainbow in polluted atmosphere ?

These days we hardly see fireflies, the Milky way, and rainbow. What’s the reason of that?\r We think the reason is related to air pollution but the concrete reason is unknown to us. Thus the purpose of this research is to see the relation between air pollution and rainbow with Aerosol. In this research we approached in some ways about why rainbow didn't appear in polluted atmosphere.

上樑不正下樑歪-脊椎側彎的探討

台灣大多數學校並無全面性脊椎側彎篩檢與追蹤的健康服務,因此學生脊椎側彎的問題都不易被發現。本研究的目的希望藉由長期的追蹤與鼓勵學生進行治療,以降低脊椎側彎的盛行率與側彎角度。台灣地區學齡兒童脊椎側彎的盛行率大約是3-3.5%,而本校脊椎側彎的盛行率大約在1%左右,而且女生明顯多於男生。根據篩檢發現本校脊椎側彎較易發生在BMI(Body Mass Index)值較低的學童身上,也就是說,瘦型體格罹患脊椎側彎的機會較高。脊椎側彎可以藉由簡單的目測及儀器測量實施篩檢,並配合醫師復健運動,可達預防與治療之效果。本校實施兩年即約有60%的成效。因此建議將脊椎側彎納入學校健康檢查的項目之一(包含國小五、六年級與國中階段)。 ;The scoliosis of school children cannot be discovered easily because the overall scoliosis screening and tracing are not provided in most schools in Taiwan. The main purpose of this study is to reduce the prevalence rate and the angle of scoliosis by proceeding scoliosis screening continuously, and encouraging the patients to take physical treatment at the same time. Compared with the scoliosis prevalence rate in Taiwan(3-3.5%), the rate in our school is about 1%. Furthermore, the girls with scoliosis are outnumber the boys with the disease. This study shows children with low BMI value will have higher probability to acquire scoliosis. In other words, thin children may fall victims of the disease more often. The scoliosis can be examined with some easy methods, such as unaided-eyes measuring or scoliosis detecting. Besides screening, hospital treatment can attain the effects of prevention and cure. For the first two years, the practice of scoliosis screening in our school can improve the disease obviously (about 60%). In conclusion, the study strongly suggests the scoliosis screening can be included into an item of health examination from the fifth graders to the ninth.