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
含環胺-亞胺雙牙配基及其鎳錯合物的合成、結構鑑定，及烯烴催化聚合反應
本研究合成含環形胺—亞胺雙牙配基鎳金屬催化劑，用以催化烯烴聚合反應。將2-甲基丙醛經由溴化、胺化及亞胺化的步驟合成含胺—亞胺的雙牙配基，Et2NCMe2CH=N(2,6-iPr2C6H3) (3a)、(c-C4H8)N- CMe2CH=NPh (3b)、RNCMe2CH=N(2,6-Me2C6H3) (R = c-C4H8 3c，c-C5H10 3d)。再將配基和Ni(DME)Br2 (DME = 1,2- 二甲烷氧基乙烷) 反應， 形成鎳金屬錯合物Ni [Et2NCMe2CH=N(2,6-iPr2C6H3)]Br2 (4a)、Ni[RNCMe2CH=N (2,6-Me2C6H3)]Br2 (R = c-C4H8 4c，c-C5H10 4d)，並作結構鑑定。其中3b、3c、3d、4c、4d 均為合成的新化合物，4d 獲得X 光單晶繞射結構。
以合成之鎳錯合物作為催化劑，催化乙烯或降冰片烯(C7H10)的聚合反應，探討反應活性和高分子產物的性質。與含相同碳數的錯合物比較，在胺基具環形取代基的錯合物對乙烯的催化活性較佳，聚乙烯產物分子量較高，分子量分布範圍狹窄；其對降冰片烯的催化活性略遜於非環形者。同為環形取代基時，六環較五環者對乙烯的催化活性較差，但對降冰片烯的催化活性較佳。顯示乙烯聚合與降冰片烯聚合有不同的反應決定步驟。催化劑及配基的設計的確可以操控聚合反應及其高分子產物的性質。
The synthesis of α-amino aldeimines Et2NCMe2CH=N(2,6-iPr2C6H3) (3a), (c-C4H8)NC Me2CH=NPh (3b), RNCMe2CH=N(2,6-Me2C6H3) (R = c-C4H8 3c，c-C5H10 3d), as well as the nickel complexes Ni [Et2NCMe2C- H=N(2,6-iPr2C6H3)]Br2 (4a), Ni[RNCMe2CH=N (2,6-Me2C6H3)]Br2 (R = c-C4H8 4c，c-C5H10 4d) has been succeeded. Their structures were mainly determi ned by spectroscopy or elemental analysis. The complex 4d was characterized by X-ray crysta llographic analysis. It shows that the nickel complex has distorted tetrahedral configuration.
The catalytic reactions of ethylene or norbornene polymerization using the newly synthesized nickel complexes are studied. All catalyts show high activity toward studied olefin polymerization. Comparing the data of the catalytic ethylene polymerization for complex 4c with those of its isomer complex 4a, the former is found to results in higher activity as well as the larger molecular weight of the PE products with the narrower dispersity. On the contrary, 4c shows lower activity in the reactions of norbornene polymerization than 4a. For the cyclic amine derivatives, 4c of five-membered amino group shows better catalytic activity toward ethylene polymerization than 4d of six-membered amino group. But 4d gives better perfomance for norbornene polymerization than 4c. Such results indicate that the processes of ethylene and norbornene polymerization might have different rate-determining steps. These study confirms that the design of ligand and catalyst are crucial with respect to the control of the catalytic olefin polymerization and the properties of the polymeric products.
攀蜥，攀棲－由台北市內湖金面山區生態因子分析夜晚黃口攀蜥之停棲策略
For this research, the nocturnal perching habits of the lizard, Japalura Polygonata Xantbostona, were examined. Nighttime observations were made from July 2002 to March 2003 in the area along the mountain brook in the south valley of the King-Mien Mountain in Nei-Hu District. The study comprised a series of analysis with discussion of the lizard’s (Japalura Polygonata Xantbostona) perch based on the temperature of living environment and the manner of perch including the dissimilarity between male and female, adults and juvenile lizards in selecting their perch conditions. During the period of study 452 lizards were marked and examined. 163 were female, 168 were male, and 121 were young lizards. The study considered four particulars: (1) orientation, (2) angle, (3) manner of perch, and (4) height of the perch above ground. As for the orientation, most of the lizards chose to perch in an inward (towards the tree) and in an upward direction; the angle of perch was mainly within 1°~ 45° and slanted to 180°. Second, the manner of perch chosen by most of the lizards was holding the stem or trunk by arms. All four groups of lizards exhibited no difference in the orientation, angle and manner of perch. However, male lizards tended to perch at a greater height above ground than the female and juvenile lizards did. The study produced other findings as well: A tendency correlation curve was plotted showing that temperature related with the number of lizards taking perch, and from the curve the optimal temperature of the living environment was determined to be approximately within the range of 19° ~24°. Additionally, there was a relationship between temperature of living environment and the size of lizard and the number of lizards taking perch. A further positive relationship was observed between temperature and the height of perch above ground. Also, the study showed an apparent positive relationship between the temperature of sample living area and the snout-vent length(SVL) of the lizard. Finally, the Japalura Polygonata Xantbostona tended to take their nocturnal perches within a rather fixed home range. 本研究由2002 年7 月至2003 年3 月，於臺北市內湖區金面山南麓溪谷進行黃口攀蜥夜 晚停棲策略研究，以溫度和各項停棲行為進行來分析探討，包括黃口攀蜥的成幼蜥、雌雄蜥 停棲選擇上的差異。 研究期間，共標記到452 隻攀蜥，其中雌蜥163 隻、雄蜥168 隻、幼蜥121 隻。將停棲 的情況分為方向、角度、停棲型態、離地高度四項來分析，在方向上多以朝內、向上為主； 角度多以小角度的1°~45°及180°為主；在停棲型式多以環抱莖枝為主。進一步分析成幼蜥、 雌雄蜥不論在方向、角度、停棲型式的選擇上皆無差異。離地高度的部分則以成蜥及雄蜥的 停棲高度較高；以溫度分析黃口攀蜥的成幼蜥出現停棲隻次、停棲高度、出現停棲攀蜥體型 的相關性，溫度對出現停棲隻次可以做出趨勢相關曲線，估算攀蜥的停棲有一最適宜溫度範 圍約在19~24℃間；溫度與其停棲高度呈現正相關性；每次測得樣區溫度與出現停棲攀蜥平 均吻肛長有顯著的正相關。而黃口攀蜥夜晚婷棲時則會傾向於較固定的範圍內。