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)).
榕樹粗萃取液對種子萌發及生長之影響
相剋作用是指植物在代謝過程中釋放出有毒物質以抑制本身或鄰近植物種子萌發及植株發育生長的過程。一般認為，榕樹是具有相剋作用的常見植物，但很少見到相關的文獻探討。本實驗利用榕樹不同組織萃取液，以小白菜、結球白菜與阿拉伯芥作材料，探討該萃取液對上述植物發芽與生長之影響，結果顯示榕樹葉萃取液所造成之影響較顯著，不同榕樹組織的萃取液、不同濃度的萃取液對不同植物所產生的效果不盡相同，針對不同生長期的植物進行處理所造成的影響亦有差異。進一步以管柱層析法與高壓液相層析法（HPLC）分離葉萃取液，結果發現以正己烷和乙酸乙酯75：25為沖提液的條件下，於HPLC的層析圖中分離時間約8分時所流出的物質具最明顯的抑制作用。電泳剖面分析顯示處理與未處理間有些許蛋白質條帶差異，此變化蛋白可能與植物幼苗對該萃取液之耐受性有關。利用核酸微陣列(microarray)對榕樹萃取液處理之阿拉伯芥植物進行基因表現分析，發現榕樹萃取液對植物部分基因表現也有促進和抑制的情形，經由基因體與蛋白質體分析法可推論出一些受影響之相關基因。 Allelopathy was defined as a phenomenon which certain plant species, by secreting metabolites to the environment, can suppress the growth of themselves, seed germination and/or growth of other plants in the same habitats. Banyan （Ficus microcarpa L.f.） is a plant species in our campus likely to have allelopathy effect. However, documents describing such action on allelopathy were rare. In this study, we applied the crude tissue extracts including leaves, stems, roots of banyan onto the germinating seeds of Pai-Tsai （Brassica rapa L.ssp.chinensis（Rupr.（Olsson）））, Chinese cabbage （Brassica pekinensis Rupr.） and Arabidopsis（Arabidopsis thaliana, ecotype Columbia-0） to study the effects of such plant extract on the germination and seedling growth of other plants. It is found that allelopathic effects on seed germination vary among different tissues used for extract preparation. Different concentration of the extract also yield various degree of allelophathic effects. It is also noted that the application of extract onto the post-germinated sprouts has less effects on plant growth. The extract of leaves was subsequently chromatographed over silica gel using hexane/EtOH gradient solvent system and HPLC. The result showed that there was one fraction about 8 min in the chromatography of HPLC eluted with 25% EtOAc in hexane had the most inhibitory effect. SDS-PAGE analysis on the electrophoretic profiles of water soluble proteins has explored a different band pattern between the treated and non-treated sprouts. The observed band difference might provide a clue for exploring proteins which reacted differently upon the application of extract. DNA microarray analysis on the effect of banyan extract on Arabidopsis gene expression has also been employed to characterize genes responsive to the allelophathic treatment. Cross-comparison between the differential transcript and protein profiles will reveal key regulators in plants experiencing allelophathic condition. \r
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。
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.
蟋蟀的聲音分析與聲音行為探討
蟋蟀聲音與行為的關係密不可分。取北部四種蟋蟀樣本，以數位錄音筆錄製及電腦軟體分析蟋蟀的聲音，並用PCR技術萃取蟋蟀的粒線體DNA(16S)加以分析，藉此和傳統的形態學分類相互比較。結果發現蟋蟀聲音的頻率特性中主頻率的差異在親緣遠近有關聯性，但聲音的時間特性方面則沒有特定關聯，不過聲學分析圖仍可作為單一種的鑑定指標。此外，研究發現此4種蟋蟀的聲音頻率範圍有重疊現象，但主頻率、脈衝比、唧聲率及唧聲長不同，推測雌蟋蟀應是綜合這些特性辨別同種。另一方面，以黑蟋蟀作為研究對象，進行干擾實驗，觀察並繪製出其聲音行為模式; 並將此作為對照，結果發現蟋蟀的生殖行為主要受到雄蟋蟀的聲音支配，而雄蟋蟀則以嗅覺辨別雌蟋蟀位置，決定下一步行動，與視覺較無關係。 Cricket's voice is closely related to the behavior. We select four species of crickets from the northern Taiwan to study the acoustic and mating behaviors. The digital sound recorder and acoustic software are used to analyze their acoustic characters. Furthermore, the PCR technology is used to amplify and sequence parts of mtDNA sequences and the results were compiled as the comparison to the traditional morphological character. The result shows that the resolution in acoustic characters of main frequency, pulse number, chirp rate, and the length of chirp are different among four species, though the minor frequency pattern is overlapping. Moreover, we find that frequency characteristic difference among four species is partly related to their phylogenetic relationship, yet is not seen in time characteristic. It is obvious that difference of acoustic behavior can be regarded as identified index among species. Results of acoustic analysis impel us to infer that the female crickets take the comprehensive acoustic behavior to distinguish their specific male. In addition, behavior pattern and model of Gryllus bimaculatus are established as the comparison of interfering experiment is undertaken. Which results suggest that the mating behavior in cricket is dominated by males’ acoustic behavior, and is initiated by male’s olfactory sense rather than that of sight.
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.
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.
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.
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.