全國中小學科展

臺灣

幾丁聚醣包埋酵母菌球株對重金屬離子廢水處理

本實驗的目的,就是希望利用幾丁聚醣除污的效果,再配合酵母菌所能累積金屬的能力,以酵母菌包埋於幾丁聚醣的方法,吸附廢水中的重金屬離子.用Langmuir 理論求得飽和吸附量,進而求出休眠酵母菌-幾丁聚醣所能吸附金屬離子(銅)0.2048(g/g)的數量,與活化酵母菌-幾丁聚醣所能吸附金屬離子(銅)0.1750(g/g),並比較回收效率,以應用於處理工業上工廠所排放的廢水. In this experiment , we want to use the ablation of chitosan and the accumulation in metal of saccharomycete to absorb the metal cation of waste liquid . In the process , we embedded the saccharomycete in chitosan to absorb the metal cation , and obtained the impregnate absorption of dormant saccharomycete and activated saccharomycete by the theory of Langmuir . Then , we compared the efficiency of them and applied them to work on the waste liquid in industry.

倍位元灰度影像產生器

本研究設計一新型的影像投射系統,可將影像顯示的灰度位元加倍,例如,顯示面板只需用4位元,即可顯示8位元的影像;亦能充分利用光路光源,增加光源使用率。此系統使用兩片相同灰度位元的顯示面板,此兩面板所顯示的影像經過灰度的重新處理,且各經由不同光源強度比值的光路合成後,其灰度分佈將可增為原來的平方倍。經模擬與實驗顯示,此種系統很輕易就能獲得預期目標。無論使用穿透式或反射式皆可應用於目前單片液晶面板之投影系統中;未來可望利用網板來表現灰度,應用於紅外線景物投射系統中,作為紅外線影像式尋標器靜態模擬時所需的高強度動態範圍與高解析度之影像產生器。In this study, a novel image generator utilized in a projecting system has been proposed; it can double the bits of gray-level for image display and enhance the efficiency of illumination of lamp in the optical path. With this system, a 4-bit display panel can achieve an 8-bit image display. Two display panels with same gray-level bits is adopted, images on them will be processed, and then go through different path with a proper intensity ratio. The gray level distribution of image displayed which the two images combined afterward, will be the square of that of original one. The results of simulations and experiments have approved to meet the requirements. No matter transmitting or reflective types can be applied to current projecting systems with single LCD panel. It is expected that a halftone-gray-level pattern will be suitable for this system to form an infrared scene projector, and to act as an image generator with high dynamic range and resolution for static simulation of infrared imaging seeker.

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。

探討聲致發光效應中,改變溫度,濃度,液體種類,頻率對氣泡發光的影響?

聲致發光效應(sonoluminesence)為最近二十年來相當新穎的研究領域,其基本原理是利用超聲波將水中的氣泡集中,並使之隨著超聲波快速且連續的膨脹壓縮,當氣泡被壓縮至最小時溫度急遽上升,並放出藍白色的光芒。正因為這是一個嶄新的領域,所以許多實驗是以嘗試錯誤的方法去進行,但也因此發現了一些特殊的現象:1. 氣泡在正常的頻率(30kHz)以外,經過一段不可發光的頻率後,還可在更高頻率(接近40kHz)的地方發光2. 氣泡發光效率曲線在不同性質溶液中的差異3. 針對高頻率發光及雙泡發光的部分,做了兩個相關的假設並進一步驗證,得到了相當特別的結論。至今已有許多關於此研究的成果發表,但對於同時兩顆氣泡存在並發光的雙泡發光現象(double-bubble sonoluminesence)卻還很少人研究。因此我們嘗試較系統化地分析雙泡發光,期望能夠對這個現象有進一步的認識,並對日後的多泡發光(muti-bubble sonoluninesence)研究奠定基礎。Sonoluminescence has been a very popular topic for the past twenty years. Single-bubble sonoluminescence occurs when an acoustically trapped and periodically driven gas bubble collapses so strongly that the energy focusing on collapse leads to light emission. Because it is a new topic, few related experiments on this issue have been carried out before. However, while doing the research and making adjustments at the same time we discovered some special phenomenon: 1. Besides the normal amplitude frequency (30kHz) added on the bubble, we found that after a period of frequency which can not emit, the bubble is able to remain and emit in higher amplitude frequency (about 40 kHz). 2. We also compared the emission efficiency when bubbles are in different liquids. 3. To explain part of the results in high frequency and double-bubble sonoluminescence, we made two assumptions and attempted to demonstrated them in the end of the report. Some research studies in this field have been released already; nevertheless, few people concentrate on “double-bubble sonoluminescence.” Therefore, we attempt to systematically analyze the emission of double-bubble, expecting to have more comprehension of this marvelous effect and also establish the fundamental background to “muti-bubble sonoluninescence.”

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)).

The role of miRNAs in plant development and virus defense

微型RNA是最近發現的小RNA,調控生物體內的反應,包括生長、細胞分化、對抗病毒…等。植物利用RNA干擾 (RNAi) 或過敏反應 (HR) 對抗病毒感染。有趣的是,miR168可藉由降解mRNA或抑制轉譯,調控阿拉伯芥AGO1的表達,而AGO1是RNAi的一個重要元件。miR398則調控銅鋅超氧化物歧化? (CSD1, CSD2) 的表達,而CSD1, CSD2負責產生過氧化氫去引發細胞凋亡 (cell apoptosis)。帶有竹嵌紋病毒 (BaMV) 全長基因的轉殖菸草 (Nicotiana benthamiana) 品系27-17是我們的研究材料。27-17的幼葉不具病徵,隨著葉子的生長,病徵會漸漸變嚴重。我發現被病毒感染時,植物會提高AGO1的表達,使RNAi更有效率。然而,病毒藉提高miR168使AGO1的量無法上升。植物亦可提高CSD1, 2 mRNA的量,促進細胞凋亡。病毒卻會引發miR398降解CSD2 mRNA。在病毒力價高的葉子中,雖然CSD2 mRNA降低且miR398升高,植物仍可大量提高CSD2蛋白的量。CSD1 mRNA沒有被miR398負調控,詳細原因仍有待研究。

氣流式薄膜測厚儀

醫學上的植皮手術成功率受皮膚厚度影響,皮膚愈薄癒合速度愈快,其中以取皮厚度介於0.05mm 到0.1mm 為佳。在實驗量測時,需要經過一連串繁複的薄皮標本製作,再放到光學顯微鏡下測量,這種厚度測量方式不但耗時,又因嚴重損毀皮膚而不精確。由於使用螺旋測微器做接觸式測量會有形變的問題,因此我們想做間接接觸式的測量,所以採用氣體為媒介,做非破壞性檢測膜厚,這對於在皮膚上的施力遠小於螺旋測微器或是接觸式膜厚計。我們設計一套三頭連管線,使用空氣為媒介,儀器運作原理為在管線一端針頭非常靠近被測物時,所流出的氣體會受到被測物阻礙產生反壓使管線內的壓力上升,導致連通於另一管路的氣泡指示計壓出氣泡,當氣泡為最大氣泡時(半球形)視為達到平衡狀態。實驗時先用已知厚度且不變形的蓋玻片來當作被測物,此時可以算出針尖至蓋玻片的實際距離做為參考值。在量測軟性薄膜時,設計上採用兩側雙針頭靠近軟性被測薄膜兩側以達到氣流氣泡平衡,這時使用螺旋測微器讀取兩針尖距離,減去已知參考值的兩倍距離,即可測出未形變的軟物質厚度。本研究開發一套能測量軟性薄膜的厚度裝置,尤其在皮膚厚度測定上,不但不會直接接觸標本造成損毀,並且能夠快速地測量出厚度值,此為本儀器的最大特色。The thickness of skin graft has deterministic influences on the success of graft surgery. Experimental measurements of skin graft thickness involve complicated specimen preparation processes followed by optical microscopic examination, which are time-consuming and may incur inaccuracy due to possible damage. Here we propose a novel method using air as the media to avoid direct contact of the measured object. The physical operation relies on the following principles: When the tip of a needle connecting to a catheter system is placed close to the object to be measured, the air pumped forward from the catheter system becomes impeded by the object. The resulting backflow pressure opposing the air flow causes an increase in air pressure within the catheter and inflates the bubble connected at the other end. Balance at maximal surface tension is attained when the bubble reaches its maximum volume in hemispherical shape. In practice, a two-needle design was used, each approaching simultaneously from each side of the object. A micrometer was then used to read the distance between the two needle tips, from which the film thickness was derived, subtracting the thickness of the air layer pre-calibrated using cover glass with known thickness. The system implemented was capable of measuring thickness on soft thin films with an accuracy of ± 0.001mm. In addition to rapid measurements with high accuracy, since the pressure exerted on the skin graft is much less than in conventional calipers requiring direct contact, our method has the unique non-distorted and non-destructive advantages.

磁性流體可調性折射率特性之研究與應用

磁性流體(magnetic fluids)是一種含有磁性奈米粒子的液體,當磁場外加於磁性流體時,流體中各磁性奈米粒子的磁矩會沿外加磁場方向排列,而導致粒子間相互吸引,形成較大的磁性叢集,即所謂的磁鍊。當外加磁場增強,該磁鍊數會變多,並使磁性流體的折射率產生變化。磁性流體的折射率變化會隨外加磁場之變大而增大。本研究除探討磁性流體折射率受外加磁場控制的變化情形及其物理原由外,並進一步運用此特性研發可調性光纖「光調制器」 ,以探討磁性流體可調性折射率應用在光電元件上的可行性。A magnetic fluid is one kind of colloids which contain magnetic nano-particles. Under an external magnetic field, the magnetic moment of nano-particles is aligned along the direction of the external magnetic field. This leads to the agglomeration of magnetic particles and to form magnetic clusters under an external magnetic field. With the formation of the magnetic clusters, the refractive index of magnetic fluid is varied. The refractive index of magnetic fluid was found to increase under a higher magnetic field. In this work, In addition to investigating in detail the behavior of the field-dependent refractive index of the magnetic fluid, we also explore the relevant physical origins. Furthermore, the feasibility of developing fiber-optical modulators by utilizing the tunable refractive index of magnetic fluids is discussed.

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.

新竹北埔冷泉蝦子之研究

因特殊的地理關係而形成奇特之新竹北埔冷泉,其水溫長年偏低且水質特殊。本研究報告主要在探討生長於冷泉中的蝦子其所屬物種、生命力、生態及新竹科學園區所排放的廢水對其生存之影響等議題。為能獲得科學與客觀性的結果,我自己設計了實驗以及適當的實驗步驟來幫助我找到解答,這也讓我對問題有深入的瞭解。我發現這些黑殼沼蝦,螯足各節間有粗糙橙斑,可以耐7℃的低溫,靠嗅覺覓食,小蝦在前4 週呈快速的成長,污水中的蝦子短期內一定死亡,從基部斷肢才能有再生能力等結果。茲條列所探討的問題如下:1.探討北埔冷泉蝦的身體構造與其功能。2.了解北埔冷泉蝦和一般食用蝦身體構造的差異性。3.探討北埔冷泉蝦的生長環境與其行為之關係。4.探討北埔冷泉蝦的食性。5.探討北埔冷泉蝦的覓食行為。6.探討北埔冷泉蝦與養殖蝦存活率的差異性。7.探討北埔冷泉蝦與養殖蝦的耐溫能力。8.瞭解北埔冷泉蝦的雌、雄判定。9.探討北埔冷泉蝦交配與孵卵方式。10.探討北埔冷泉蝦小蝦的成長曲線。11.探討不同水質對北埔冷泉蝦的影響。12.探討北埔冷泉蝦斷肢後的再生現象。經由這次的研究,讓我對北埔冷泉蝦子的身體構造、生長環境、覓食行為、耐溫能力、交配與孵卵、小蝦的成長、斷肢後的再生、甚至水質對蝦子生存之影響等等已能深入瞭解。除此之外之外,更重要的是從疑問的產生,實驗方法與步驟的構思、做實驗的過程,及獲得可信的結果,再再使我深刻體會到科學精神的真諦。Bei-Pu cold spring of Hsinchu was formed due to the unique geographical feature. This paper investigates the species, livability, ecology and affection of water quality of the wildlife shrimps that live in this special environment. I design my own experiments and suitable procedures to help me to get the scientific and objective results. The research topics on Bei-Pu wildlife shrimps are listed below. 1. Body structure. 2. Distinguish bred and this wildlife shrimp. 3. Growth environments and its behavior. 4. Foods. 5. Hunting 6. Livability. 7. Tolerance of low temperate. 8. Male and female. 9. Mating and incubating. 10. Growth characteristics. 11. Affection of water quality. 12. Limbed and re-generation. These crayfishes can survive under 7℃. Hunting behavior is guided by olfaction other than vision. They grow rapidly in the first 4 weeks. Regeneration occurs only from the joint. Water quality is vital to them. From this study, I understood the species, hunting, mating, incubating, growth, temperature tolerance and regeneration of this wildlife shrimps. Moreover, I deeply appreciate what real scientific essence is through defining the questions, designing the experiments, procedures and obtaining the results finally.