全國中小學科展

臺灣

平面式雙頻天線合成陣列之研究

The feasibility of new design approach for dual-band antenna array using genetic algorithm is demonstrated in this study. In the past year, one dual-band printed-strip dipole antenna, which operates at 0.9/1.8 GHz, had been implemented in the laboratory and leads to a satisfactory performance. However, the antenna element is suitable for application at base-station rather than handset. Conventional antennas suitable for base-station application are arrays, which consist of antenna elements and at least one feed network. Feed networks for antenna arrays are usually designed to operate at single-band capability, and therefore, it requires two feed networks for a conventional dual-band antenna array. Nevertheless, a dual-band antenna array fed by signal feed network is feasible in our study. To begin with, a full-wave solver ID3D is applied to evaluate the impedance matrix of antenna array with eight elements. Then, the antenna array is modeled as a cascaded equivalent transmission line such that the genetic algorithm could network of dual-band antenna array and yields a seven-section design, which meets the specification of base-station antennas.在過去的一年裡,本人曾製作過具有雙頻效果的雙面印刷偶極天線,並得到不錯的量測結果。由於此天線單元於實際應用上適於基地台天線陣列之設計,所以本研究著眼於天線陣列的設計。傳統上天線陣列的結構包含了兩個部分,分別是天線單元以及饋入電路。目前基地台所使用的大多都是單頻天線陣列,在雙頻天線陣列部分,通常需要兩個饋入電路分別對不同頻帶作訊號的饋入;因此,我們希望能實現使用單一饋入電路製成雙頻天線陣列的想法。本研究中,我們利用之前所做出來的天線單元來合成陣列,並希望此陣列在0.9HGz和1.8GHz兩個頻段都能產生良好的共振效果。我們利用電磁模擬軟體IE3D估算具有八個天線單元的天線陣列阻抗陣列後,再將此天線陣列轉換成串接式等效傳輸線電路。借由基因演算法(genetic algorithm)對此電路做最佳化,我們可以求得饋入電路各段傳輸線的尺寸。由此研究發現,我們的方法應用於單一饋入電路之雙頻天線陣列的設計是可行的,而此電路的模擬結果亦符合基地台天線陣列的規格。

架構「類球狀多面體」的理論與實務

本報告的目的在:電腦Cabri 3D 軟體上模擬出「類球狀多面體」(圖1-8),\r 並實作其模型(圖9)與它們的星體(圖10)。「類球狀多面體」的定義如下:\r 可由「正多面體」切出之多面體,且需滿足以下性質:(1) 除「正多邊形」外,\r 其餘皆是「六邊形」。(2)鳥瞰每個「正多邊形」時,形狀皆保持不變。(3)\r 等長的稜數最多。\r 以「正十二面體」切出之「類球狀多面體」為例,(圖1)中兩個「正五邊形」\r 相距一個「六邊形」簡稱A1。(圖2-4)依序為A2、A3 與A5。正二十面體可切\r 得(圖5-6),正六面體可切得(圖7-8),......等。(圖9)為A2 的實體模型,\r (圖10)為A2 的星體模型。

果蠅單眼的發育調控基因之篩選

在果蠅成蟲的頭頂上方三顆可以感光的單眼(ocelli),其構造和複眼有顯著的差異,但單眼及複眼在果蠅幼蟲時期,皆從一片特別的組織eye-antenna disc發育而來。而且目前已知會表現在單眼的一些特定基因,也是會調控複眼發育的基因,如sine oculis (so),eyes absent (eya) 等。但到底是哪些特定的基因決定了單眼與複眼的差異,目前並不是很清楚,因此我想探討果蠅單眼細胞在發育過程中,有哪些特定的基因會調控果蠅單眼的生成與變化。 本實驗主要是利用果蠅研究上常使用的基因表現系統(UAS-GAL4 system)進行研究,我們挑選許多和複眼發育相關的基因、胚胎生長發育相關基因進行表現,觀察其單眼性狀有無變化,篩選出會影響單眼發育的相關基因後,再進一步研究此基因的可能作用機制。 從實驗的結果中發現當表現ras及Egfr的顯性抑制型 (rasDN, EgfrDN)時,在掃描式電子顯微鏡下可觀察到三顆單眼會明顯變小。而在幼蟲時期的eye-antenna disc,利用免疫螢光染色以及雷射共軛焦顯微鏡觀察到當表現rasDN、EgfrDN時, 單眼標記基因(marker gene) Eyes absent (Eya)表現的強度顯著降低。再加上已知ras為Egfr的下游基因,綜合這些結果,我們認為Egfr-Ras 以及其下游基因的訊號傳遞對於單眼發育是很重要的。 另外在視網膜電流圖(electroretinogram)的實驗當中,發現Egfr, ras訊息傳遞被抑制的果蠅單眼在對光線刺激的反應強度比起正常的果蠅下降許多,因此可推論Egfr, ras的訊息傳遞不僅會影響單眼的發育,也會影響單眼的正常感光的功能。

電解質電容器

本研究主題是要探討以電解質作為電介質之電容器的放電情況及電容值。作者在電容器的兩極板中,灌入電解質溶液,作為電介質,發現確實能使電容值大增。作者再以不同電解質和外加磁場為變因,作出以下研究,以深入了解電容和電解質溶液的關係。The main idea of this topic is to explore the amount of capacitance with electrolyte as dielectrics. The authors poured electrolyte solutions into the polar plate of capacitor and found the amount of capacitance increased. Then the authors used the different kinds of electrolyte and added magnetic field as changing factors. Authors performed the following research to deeply find out the correlations between capacitance and electrolyte solutions.

鋅電極低污染性金屬浸鍍處理對銀鋅電池的影響

Because the electrolyte solution used in an alkaline battery is a concentrated KOH solution, the zinc electrode in such a battery undergoes both a charging reaction and a corrosive reaction with the alkaline solution. The corrosive reaction not only reduces the lifetime of the battery but also produces hydrogen, which can cause the battery to explode and burn. Most of the zinc alkaline batteries currently on the market use mercury plating on the zinc electrode to increase its resistance to corrosion. To reduce corrosion of the zinc electrode in an alkaline battery and to avoid the use of toxic mercury, this study aimed to design a device to measure the quantity of hydrogen gas produced during the charging of a zinc-silver battery. We plated the zinc electrode with the immersion electroless plating method, using several different kinds of low-polluting anticorrosive additives(metallic compounds such as lead, tin, and indium)instead of mercury. We also used the vacuum immersion electroless plating method and added zincate ion into electrolyte solution to reduce further the quantity of hydrogen produced. The results of the experiment revealed that either a 10:1 or 100:1 ratio of lead to tin under optimal conditions will yield much better results than mercury.鹼性電池中使用的電解質溶液為濃氫氧化鉀溶液,因此電池中的鋅極除了放電反應之外,也會與濃鹼溶液中發生腐蝕反應。鋅極的腐蝕作用不僅會降低電池放電壽命,而且所產生的氫氣更可能使電池發生爆裂燃燒的危險。目前市面上所售之含鋅鹼性電池,大多是用鋅極鍍「汞」作為鋅極抗腐蝕的方法。為了改善銀鋅鹼性電池中鋅極在放電時的腐蝕效應,以及減少其所產生的氫氣量,本實驗設計了一動態放電裝置,可用於檢測銀鋅電池的放電電壓、放電時間與鋅極腐蝕反應的氫氣生成量。本研究藉由浸鍍其他低污染性金屬溶液 (鉛、錫、銦的化合物)來取代不環保的鍍汞製程,並進一步設計抽真空的浸鍍裝置,以及電解質溶液採用含有ZnO22-的KOH溶液,有效的降低電池中氫氣生成量。最後綜合所有優良條件,以鋅極採用真空浸鍍(Pb:Sn)為(10:1)及(100:1)的條件,此舉非常有效地提高電池中鋅極抗腐蝕性。此項製程所使用的Pb、Sn污染性質遠遠低於目前工業上所使用的汞製程污染,而且製程成本也遠遠低於Hg製程成本。

均相沉澱法製備CZA 觸媒之探討

本研究以均相沉澱法合成多成分的銅鋅鋁觸媒系統,並嘗試克服傳統共沉澱法的不均勻性且提高比表面積,過程中我們利用改變尿素濃度、水添加量、反應溫度與時間等四種變因成功合成出具有高活性的銅鋅鋁觸媒。研究得知最佳的合成條件為尿素3M 並添加三倍體積的水,在95°C 下反應2 小時。與傳統觸媒相比,均相反應合成的銅鋅鋁觸媒除了有較小的粒徑外,其還原溫度也較低,顯示較佳的觸媒活性。而在250°C 甲醇重組的製氫反應條件下,均相反應合成的銅鋅鋁觸媒也有較高的甲醇轉化效率、氫氣產生率以及CO2 的選擇率,而添加鈰與鋯可更進一步使觸媒活性再提升。未來除可利用此合成方法合成均勻性佳的多成份材料,亦可應用此高效能觸媒進行甲醇重組反應以產生氫氣提供燃料電池使用。; Multi-composition Cu-Zn-Al catalyst system was synthesized by homogeneous precipitation method. This method was anticipated to improve the homogeneity of metal mixing and to increase the surface area of catalyst derived by conventional co-precipitation method. In the research, we successfully synthesized Cu-Zn-Al catalyst with high activity by adjusting four experimental parameters -- urea concentration, water amount, reaction temperature and reaction time. The better catalyst can be obtained under urea concentration of 3M diluted by 3 times water, and the kinetics conditions of 95°C and 2h. Compared with the co-precipitation method, homogeneous precipitation method derived Cu-Zn-Al catalyst performed higher methanol conversion, hydrogen production rate and CO2selectivity under methanol reforming reaction at 250°C. Modifying the support by addition of Ce and Zr might further improve the activity of the catalyst. In the future, not only can this method apply on synthesizing other multi-composition materials with high homogeneity, but also the high performance catalyst can be used to do methanol reforming reaction in order to supply hydrogen on fuel cell.

塑膠海岸-臺灣東北海岸微小塑膠污染之研究

一、目的:1.找出基隆沿岸是否受到塑膠微小物的污染,建立塑膠成分的簡易檢定法,3.分辨所發現塑膠微小物成分,4.試圖分析其污染源,並尋求減輕汙染方法。二、結果:本研究為首篇證實東北部海岸已遭受塑膠微小物污染之本土研究。我們想出了不用昂貴儀器的位之塑膠簡易成分判別法,發現海面漂浮的油渣含有塑膠微小物,還觀察到海岸生物(藤壺)由本來附生在岸邊的石頭上轉而附著於漂浮的塑膠垃圾及漁民和釣客所使用的浮標、漁網、浮桶等。三、為減少海岸的塑膠微小物污染,建議政府立法規定業者主義塑膠原料運送中產生的問題,並提倡垃圾分類,人民本身也應自我覺醒。Taiwan is an island, and the sea is very important for us. So in this study, we tried (1) to examine the small plastics (resin pellets and plastic fragments) pollution of the northeast coast, (2) to identify the components of unknown plastics by burning, soluability in organic solvents and relative weight but without using expensive instruments, and (3) to classify the small plastics we found and to find out where were they from. Our study is the first grassroot research proving that the northeast coast of Taiwan has been polluted by small plastics. We attempt to identify the components of unknown plastics without using expensive instruments. The present study discovers that there are many small plastics in the floating oil scum. The relation between the oil scum and small plastics needs more study. We finds marine life (bamacles) growing on floating small plastics. The ecological importance of this discovery needs more study. We also make suggestions for reducing the minute plastic pollution of the coasts: (1) the government should ask big companies to be more careful on the transport of plastic pellets, (2) people should be aware of the problems caused by small plastics.

類固醇對斑馬魚胚胎細胞的影響

Steroid hormones are very important for physiological homeostasis, but some functions of steroids are still unclear during embryonic development. Embryonic cell movements are required forming embryonic body. Recently, there is already known Pregeneolone (P5) which could affect epiboly movement of zebrafish embryos is the first product of the steroidogenesis pathway, but effects of further downstream products on epiboly movement are unknown. In order to know this, we treat embryos with Pregnenolone (P5), 17α-Hydroxypregnenolone (17OH-P5), DHEA, Progesterone (P4), 17α-Hydroxyprogesterone (17OH-P4), 11-Deoxycortisol (D), or Testosterone (T). We found out that P5 can accelerate epiboly movement, 17OH-P5 and D have no significant effects on it, and DHEA, P4, 17OH-P4, and T can decelerate it. These results indicated that steroids play important roles on embryonic epiboly movement in zebrafish. 類固醇荷爾蒙對生理平衡很重要,但其對於胚胎發育的影響仍舊不明。胚胎個體的形成需要胚胎細胞進行不同的移動排列。目前研究已知類固醇荷爾蒙生合成機制的第一個產物pregnenolone (P5)對斑馬魚胚胎epiboly 移動有影響,但其它更下游的類固醇荷爾蒙對epiboly移動的影響仍然未知。為了了解類固醇其他下游產物對魚卵早期細胞移動的影響,將胚胎處理Pregnenolone (P5) 、17α-Hydroxypregnenolone (17OH-P5) 、DHEA 、Progesterone (P4) 、17α-Hydroxyprogesterone (17OH-P4)、11-Deoxycortisol (D)、Testosterone (T),發現17OH-P5、D對epiboly 的移動沒有影響,而DHEA、P4、17OH-P4、T 會使其變慢。這些結果說明了類固醇對胚胎細胞的移動扮演著重要角色。

棋盤的費伯那契

在學校科研營的教材中,有一個題目,其內容相當於:「在一列格子中 放入黑棋與白棋。白棋不可連續放置,而黑棋不受此限,請問共有幾種可能的排列方式?,在此規則下,若將格子推廣為m列n行的棋盤,那又如何呢?我們對此好奇不已。

一些Moire patterns 的數學性質研究

Moire 為法文,其英譯為watered, 是古代織布技術的一種應用;將印有規律條?的透明薄片重疊時,稍微移動或轉動其中的一片,會形成極大的圖形變化,稱為moire pattern本作品針對三個moire pattern 的數學式加以推導:(一)、兩張透明片各印有等間隔平行線,轉動其中一片使兩線的夾角θ,亮紋垂直距離和暗?垂直距離的比值為tanθ/2tanθ 。(二)、兩張透明片各印有輻射線,重疊後行成圓系,可由代數或幾何加以證明,利用三角函數可推導出此圓系方程式為:x2+{y-rtan[π/2-(θ-?)]}2)]}={rsec[π/2-(θ-?)]}2)]}\r \r (三)、透明片A 印有等間隔平行線,B 印有符合高斯曲線的平行線,AB 重疊時,形成一系列的高斯曲線,AB 的夾角減少時,會增大曲線的曲率,我們進一步討論曲線的曲率和平行線斜率的關係。Moire is the French word “watered” and refers to an ancient technique employed in cloth making. The moire occurs whenever two or more transparent sheets with periodic strips on them are superposed. The characteristic of moire patterns is the fact that a slight shift of sheets will create dramatic alternations in the observed patterns. In the present report, We derive the equations of three different moire patterns. First of all, take a sheet with equal spaced straight lines and placed it on top of another identical sheet. They are made to intersect and form an angle of θ. As the angle changes slightly, it produces huge changes in the spacing of moire fringes. We can derive a formula related to the interfringe distance. The ratio of bright fringes and dark fringes is tanθ/2tanθ.Secondly, two transparent sheets with radial lines on them are overlapped, forming a pattern similar to the lines of force between point charges. We can find that the pattern is a series of circle by means of algebraic and geometric proofs. And proven by trigonometric functions, we canconclude that they satisfy the equation :x2+{y-rtan[π/2-(θ-?)]}2)]}={rsec[π/2-(θ-?)]}2)]}\r Thirdly, a set of lines of equal spacing is overlapped with a second set of lines whose spacing are derived from a Gaussian curve. A series of Gaussian curves is reproduced in a moire pattern. Reducing the angle of intersection between the two figures steepen the curvature. We discussed the relation between the curvature and the slope of inclined lines.