東沙島海灘的變遷與復育：由龍擺尾停擺說起
政府最近公佈在東沙群島設立第一個國家海洋公園，顯示國人重視海洋資源的保育與復育；但是東沙島特殊的自然景觀「會擺動的沙嘴」—龍擺尾，卻因興建八座消波塊構築的突堤而消散停擺。本研究以一個高中生的觀點，設計及進行一系列的模型實驗，探討東沙島的形成機制、各種環境因素對海灘及龍擺尾的演化、驗證龍擺尾的現況及如何讓龍擺尾復活，再由東沙島海灘復育看世界的海岸問題。雖然設備很克難，但都能完成預定的目標，證實東沙島的海灘演化。希望此次對東沙島海灘的研究成果與初步探討，能應用於世界上遭受侵蝕而需復育的海岸。In 2007, our government proclaimed Dongsha archipelago as the first national marine park, signifying her emphasis on the conservation and restoration of marine resources. However, the sand spit on Dongsha island, a unique natural wonder commonly referred to as the “swaying dragon tail”, has become motionless since the construction of a total of eight groins along its SE and NE coast during the period between 1993 and 1996. This study has conducted a series of model experiments to verify several fundamental issues, ranging from the formation and the factors affecting the stability and the status quo of Dongsha island and its spit. The experimental results find several favorably outcomes, giving the coast evolving evidences of Dongsha island. Furthermore, strategy to stabilize the coast and revitalize the spit are then considered, which could hopefully benefit the coast suffering erosion on the world’s coastline.
國王的海市蜃樓
在夏日的午後，在炎熱的柏油路面上很容易可觀察到遠方的 路面上，出現如鏡子般的倒影，看起來彷彿前方有一灘水，但當 我們向前進一些時，倒影卻突然消失了，這個現象，一般稱為海 市蜃樓。 一般解釋海市蜃樓的成因，都是由於在上層的低溫空氣，和 在下層靠近路面的高溫空氣，因密度的不同，以致於折射率的漸 層差異，繼而產生全反射。 但我們觀察發現，地面與上層空氣的溫差，並非柏油路面上 假積水現象及倒影出現的必要條件；反而和入射光的角度、路面 的平坦程度及路面的性質有關。我們提出了粗糙面在入射光的入 射角接近90度時，可發生單向反射的模型。並由實驗來驗證假積 水現象及倒影主要的成因是「柏油路面的單向反射」而非「空氣 的折射與全反射」。 Under the scorching sunshine, we can see the reflection on the tarmac in the distance just like a water puddle on the road. And the water also reflects the people and object nearby. But, in fact, the tarmac road over there is very hot and dry. Therefore we call the phenomenon as the “false water puddle on the tarmac.” According to the textbook , the main reason for “false water puddle on the tarmac” is that the temperature difference leads to the refraction of the light and causes the phenomenon. However, from our observation, the theory still can’t explain some phenomenon, For example, the “false water puddle on the tarmac” remains to appear when the wind blows fiercely. Even with little temperature different at night the phenomenon is still obvious. Therefore, in our opinion, the temperature different of the air is not a necessary condition of “ the false water puddle on the tarmac.” We bring up the model to explain the phenomenon that when the incident angle of the light approach 90 degrees, the light will result in one-way reflection. According to the model, furthermore, we make experiments at midnight and at dawn. The result of the experiment assures us the hypothesis of the model, Consequently, we hold the ideal that the main condition of the “false water puddle on the tarmac.” Is not because of the refraction and the total reflection but because the light reflects off the road and result in the one-way reflection on the tarmac road.
誰能比我更善變???~ 釩鎵磷酸鹽的合成及其結構鑑定
This research tries to find out how changes of weight or proportion of a reactor would affect the type and structure of a crystal. In the experiment, the Hydrothermal reaction was adopted to conduct the syntheses of Vanadium-substituted Gallium Phosphates and try to pick up the single crystal to collect data with SXRD for further illustrating the crystal structure with diamond software to know well its nature. The research result finds out a new type of crystal unseen in the existing literature produced because of the weight changes of C3H10N2, therefore the weight change of a reactor may affect the structure of crystal significantly. In the future, it is expectation that comparison among structures of other Vanadium-Substituted Gallium Phosphates can be made, and the properties of this compound can be measured, and try to find out a brand new type of structure for new exploration by changing the initial reagent.
本研究係透過改變化合物所添加之反應物的比例，以了解反應物比例的改變對晶體的型態與結構的影響。實驗採用中溫水熱反應來從事金屬釩鎵磷酸鹽的合成。並挑取單晶，以X-ray 繞射儀進行數據收集，再以diamond 軟體繪出晶體的結構圖，且進一步得知其性質。研究結果發現，經改變丙二胺的量後，產生不同於文獻上的新化合物，可知改變所加反應物的比例，對於晶體結構有相當大的影響。未來可朝向與其他的釩鎵磷酸鹽做結構上的比較、對此化合物做更進一步的性質測量、改變起始試劑測試，進而得到更新穎的結構形式等部分進行探究。
液滴在我眼前蒸發
本研究的目的在觀察液滴的蒸發過程，探討影響一滴蒸發方式改變的變因。我們利用數位攝影機外加近攝鏡頭，由側面逆光拍攝液滴蒸發過程，並轉錄成電子檔利用電腦協助分析。液滴影像分隔放大投影在方格紙上，以便測量接觸角及高度的變化。結果發現蒸發情形可分為三種：Ⅰ.當接觸角大於九十度時，液滴和界面的接觸線迅速外擴，直到接觸角遞減至90度後定住不動，蒸發終了時，接觸線迅速內縮，留下縮小的實心殘跡。Ⅱ. 當接觸角小於九十度時，接觸線先些微外擴迅速外擴，之後定住不動，直到蒸發終點，液體內縮，留下環狀殘跡。Ⅲ.當接觸角小等於九十度時，接觸線始終定住不變，液滴蒸發後留下原大小的實心班跡。液滴蒸發時接觸角和高度並不是連續變化，而是交互階梯式遞減。本研究的結果可應用在探討噴漆及噴墨印表機的噴墨印刷上。The objective of this investigation is to observe the evaporation of liquid drop and find out the factors that could affect it. A digital camera with micro lens is used to film the process of the evaporation. And a close-up of the sample drop is taken with backlight. The results are analyzed with a personal computer. The magnified images of the drops are projected on grid papers for measuring the changes on contact angles, and heights of drops. We classify the evaporation of a drop into three types: Ⅰ. The contact angle is greater than 90 degrees. At first, the contact line will spread outwardly till the contact angle decrease to the 90 degrees and then be pinned until the evaporation reach its terminal. At last the contact line quickly contract inwardly, and a solid stain remain. Ⅱ. The contact angle is less than 90 degrees. The contact line will spread slightly and then be pinned. At the terminal the liquid contract inward, and a ring-like stain is formed. Ⅲ. The contact angle is equal to 90 degrees. The contact line will always be pinned, and no ring, but spot stain is left. During the evaporation, we discover that the contact angle and the height of the drop do not change continuously but alternatively decrease by steps. The results of our investigation can be applied to the aspects of paint-spraying and jet printers.
Molecular and Cellular Responses under Hypoxic Stress among Rice Cultivars with Different Flooding T
全球暖化造成水災頻繁，嚴重威脅植物生存。看似耐淹水的水稻，在完全淹水下亦有其生存危機。水稻FR13A 因耐水性極佳而常用於分子育種，IR64 產量高卻不耐水。是那些特質使稻種間有不同耐水機制？我們觀察其幼苗淹水24 小時後生長情形、通氣組織 (aerenchyma) 變化及應用即時反轉錄聚合?鏈反應 (real time RT-PCR)，研究酒精醱酵的主要蛋白質：乙醇脫氫? (alcohol dehydrogenase, ADH1, 2) 及丙酮酸脫羧? (pyruvate decarboxylase, PDC2) 基因之表現量。兩種水稻的胚鞘及根都因淹水減緩生長，以FR13A 減緩最明顯。通氣組織在淹水期間都有增加，FR13A 中的形成近似於對照組，IR64 則明顯較差。FR13A 中ADH1 及ADH2 在淹水一小時後迅速增加60 至100 倍，IR64 僅增加10 至20 倍。PDC2 在IR64 中表現量的增加幅度較大，但最大值仍小於FR13A 之基礎表現量。由此可知，FR13A 在完全淹水時成長減緩而原有通氣組織則持續生長，且酒精醱酵中的基因有獨特誘導反應，因此耐水性較佳。藉由此研究揭開水稻細胞及分子生物學上的耐水反應策略，將可更精準地改良稻作使其對抗淹水逆境，解決未來因環境造成的糧食危機。Global warming increases the frequency of flooding, which drastically reduces the growth and survival of plants. Although rice (Oryza sativa) appears well-adapted to flooding of roots as it is often farmed in paddies, problems arise when the whole plant is submerged in water. I am interested in the structural and molecular responses that result in different submergence tolerances in rice cultivars. Indica rice FR13A is submergence-tolerant and frequently used in molecular breeding for this trait, while IR64 is a high-yield but submergence-intolerant cultivar. In this study, I monitored the growth rate, aerenchyma formation, and gene expressions of the carbohydrate metabolism in FR13A and IR64 seedlings subjected to submergence for 24 hours, by means of real time RT-PCR and microarray. FR13A had prominently inhibited coleoptile growth and sustained levels of aerenchyma formation whereas IR64 did not. The mRNA levels of alcohol dehydrogenase 1 (ADH1) in FR13A was induced prominently, while ADH2 was induced in IR64 during early hours of submergence. The induction of pyruvate decarboxylase 2 in FR13A was stronger than IR64. The expression of sucrose synthase was similar in both strains. Expressions of the genes involved in anaerobic carbohydrate metabolism were also studied by analyses of microarray data. My findings demonstrate that elongation quiescence, persistent aerenchyma formation and shifts in anaerobic carbohydrate metabolism gene expressions are beneficial strategies of FR13A towards submergence. Through elucidating the molecular basis of coordinating submergence tolerance genes as this study provided, it will be possible to discover multiple traits associated; hence crop improvement for flooding tolerance could be achieved.
氧化壓力影響基因轉換表現對脂肪分化之作用
細胞脂肪分化是造成肥胖、骨質疏鬆、和糖尿病的重要前置因素。我們若要維持良好身材又想省去減肥藥的問題，那麼我們必須了解造成脂肪化的原因，才可能擁有好的預防之道。利用人類骨髓間質細胞可以分化成骨質與脂肪等細胞的特性，我們研究氧化壓力對間質細胞\r Ras基因轉換表現後骨質與脂肪分化的影響。結果發現以添加超氧根 (O2-，l5nM)形成氧化壓力，可促進正常Ras基因表現的間質細胞朝骨質分化;相反地，超氧根會促進\r Ras基因突變而不表現的細胞，朝向脂肪分化的現象。進一步研究其作可原理，發現氧化壓力可促進 RaS蛋白質啟動細胞外訊息活化酵素(ERK)，接著驅動骨質轉錄因子(CBFA1)表現，再到骨鈣蛋白質與骨結節形成。而抗氧化酵素(超氧根轉化酵素;SOD,5OOU/ml)的作用，可以抑制正常Ras基因細胞氧化壓力下骨質分化的進行;但不能防止氧化壓力促進Ras基因突變細胞，朝向脂肪分化的作用。總結而言:Ras基因的表現與否，是決定脂肪分化的關鍵切換點;也是影響氧化壓力對間質細胞朝骨質分化的樞紐。這種基因與氧化壓力互動影響骨質與脂肪分化的剖析，將有助於提醒人們:使用抗氧化劑來調節抗衰老、肥胖、和美容時，必須是在不同情況和不同基因體質的人，有所不同。
\r Human\r mesenchymal stem cells are able to differentiate into bone, muscle, cartilage or\r fat tissues. Our preliminary study with human mesenchymal cell line (HS-5) showed\r that HS-5 cells could differentiate to bone, cartilage and muscle but not fat cells\r as determined by histochemical staining of phenotypes. We have further studied the\r influence of oxidative stress on the switch between bone and fat cell differentiation.\r Results showed that oxidative stress started with exogenous superoxide, produced\r by the interaction of xanthine oxidase and hypoxanthine, promoted the differentiation\r of osteogenic lineage showing expression of osteocalcin and bone nodule formations.\r The mechanism was investigated and superoxide was found to induce ERK (extracellular\r regulated signal kinase) activation; and then the expression of osteogenic specific\r transcriptional factor (CBFA1). A plasmid containing ras-mutant (Ser 17 Asn) which\r can inactivate the expression of ERK was transfected into the HS-5 cells for studying\r the influence of oxidative stress on ras-mutated mesenchymal cells. Surprisingly,\r it was found that oxidative stress did not promote osteogenesis but it enhanced\r adipogenesis from the ras-mutated HS-5 cells. Further studies indicated that superoxide\r neither induced ERK activation nor CBFA1 expression, but it did enhance expression\r of adipogenic specific transcriptional factor (C/EBPα) and lipoprotein lipase in\r the ras-mutated mesenchvmal cells. Taken together, the study model to induce the\r bone cell differentiation from human mesenchymal stem cells may be employed to make\r bone cells for tissue engineering.
臭氧事件日-氣象與地形對臭氧於近地大氣層之生成與傳輸影響
2001、2002 年監測資料被用以探討風場、時間、地形對臭氧傳輸影響。完成沿海地區與盆地內各二次採樣分析，探討各污染物與風場之垂直變化，及地面臭氧分布與風場變化。結果顯示各月份與全年之日間，其相對濕度與O3 相關度最高，日照次之。提高濕度，最能抑制[O3]。夜間NO 與O3 的相關度最高，濕度次之。臭氧事件日時：(1).11:00 即可產生高臭氧，(2).沿海地區在臭氧事件日仍保持低[O3]， (3).盆地效應改變風場，使近山地區[O3]居高不下，(4).因處O3 不斷被吹入，沿海地區傍晚時之[O3]下降速度減緩。臭氧事件日之O3 生成速率R 與消失速率常數L 被求出，其中14:00 後之R 與L 值均由正值轉負值，顯示大氣反應型式明顯轉變。R 與L 值在14:00∼15:00 間最小，係因O3 反應生成光化學煙霧所致。16:00 後另一低R 與L 值，則可能導因O3 與微粒或水份反應。分析結果顯示：(1).污染物會隨高程而略增，最高濃度在300∼500 m 處，(2).各高程大氣均可分析出73 種主要HC，其隨高度之分布被繪出與探討，(3).低層大氣會有較多低分子量HC，而高層大氣則有較多高分子量HC。結果亦顯示： (1).盆地內[O3]、[NO]與[NO2]不僅較沿海地區高，且於各高程之變動亦較大，(2).沿海地區THC、烷、烯類均較高，且隨高程增加而增高，但在盆地內則相反，(3).二地區各高程之鹵化物、芳香族、氧化物與其他有機物之平均濃度相近，但沿海地區之濃度變動較大。探討O3 之二傳輸現象獲知：(1).風吹向盆地內時，[O3]隨風向遞增，R 與L 會由12:00 之正值，轉為14:00 之負值；(2).風由盆地內外吹時，[O3] 隨風向遞減，R 與L 值提前於12:00 即為–202.561 與–1.621，但14:00 時R 與L 值增大為–76.411 與0.244， (3).風向並非決定[O3]的主要因素，地形與環境因素才是。實驗結果證實：(1).不同HC 會影響O3 之生成與消失，(2).改變[NO]o 對[O3]影響不大，但高[NO]會使得[O3]下降略緩，(3).降低HC 與[NOx]雖可使 [O3]略降，但提高濕度最能抑制[O3]，(4).在O3 的衰減量上，[O3]隨濕度增加而快速降低，但衰減率則隨[O3]o 的增加而降低。一個臭氧之統計模式被建立，臭氧與水反應速率常數與速率式也被求出。
The monitoring data were used to investigate the effect of surface wind, time, and terrain on the transformation of ozone. The sampling and the analysis in the coastal and in Taichung basin were completed. The vertical distribution of O3, NOX and HC and the different altitude wind were investigated. The contour of O3 and surface wind with 3D map were plotted. The results show that the correlation behaves relativity of relative humidity with ozone is the best, and solar radiation is the next. Enhancing environmental moisture can efficiently decrease ozone concentration. In each ozone event day are: (1) the high [O3] always starts from 11:00, (2) the ozone concentration on the coastal is always low due to the high humidity, (3) the high [O3] in the east of the basin is due to the basin effect which causes changes the surface wind, and (4) in the evening, the descend rate of [O3] in the coastal area is lower because ozone blows into the coastal area. The formation rate (R) and disappear rate constant (L) of the ozone event day were obtained. The values of R and L change from plus to minus before 14:00. The values of R and L are lower at 14:00∼15:00 due to the photochemical smog formation. And another lower R and L value before 16:00 may be due to ozone react with particle or water. The results of analysis indicate that: (1) the concentration increases with increasing altitude, and the maximum is at 300∼500 m height, (2) 73 kinds of hydrocarbons were identified, and the concentration variation with altitude was also investigated, and (3) most of low molecular weight HC are at lower altitude, otherwise high molecular weight HC are at higher altitude. The results also show that: (1) [O3], [NO], and [NO2] on the basin are not only lower than on the coastal, but also their variability of concentration are big, (2) THC, paraffins, and olefins on the coastal are higher than on the basin, and the concentrations increase with increasing altitude on the coastal, but on the basin is decreasing, (3) the average concentrations of halides, aromatics, oxides, and others are similar on both area, but concentration variability on the coastal is obvious. Two types of O3 transformation was investigated, the phenomenon indicts that: (1) when wind blew into the basin, [O3] increased with wind direction. The value of R and L change from positive (12:00) to negative (14:00); (2) when wind blew out of the basin, [O3] decreased with wind direction. The more small value of R (−202.561) and L (−1.621) appeared at 12:00 earlier. But the value of R and L will become bigger to –76.411 and 0.244; (3) ozone concentration does not just dependent on wind direction., topography and surrounding conditionsa are more important effect. The experimental results show that: (1) ozone formation or disappearance depends on different HC, (2) the effect 2 of [NO]o is small for ozone photochemical reaction, but [O3] decreases with increasing [NO], (3) the descend rate of O3 depends on high humidity more than different kinds of HC or [NO], and (4) the descend amount of ozone increases with increasing humidity strongly, and the descend rate of ozone decreases with enhancing [O3]o. A statistical model was developed. The reaction rate and rate constant of ozone reaction with water were also obtained.
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.