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臺灣

「天上掉下來的禮物嗎?」—討論十年來大陸沙塵暴對台灣之影響與變化趨?

In recent years, sandstorms have seriously attacked Taiwan day by day. Combining with the observations of Central Weather Bureau and the satellite images of NASA, the study has been collected the data of suspension grain in decades. And the study hopes the sandstorms’ information could be observed in early period. Still it hopes to find out the possible transmission paths in the atmosphere. Then we know how to cope with sandstorms in early time. Sandstorms attack Taiwan frequently in spring, the end of the autumn and the beginning of the winter. Compared with the charts of sandstorms and the satellite images, we could broadly aware that the moving paths of sandstorms are related to the currents and the characteristics of the atmosphere. When El Nino happens, the times of sandstorms attacking Taiwan decrease, and that increase when La Lina happens. According to the results of spectrum analysis, there might be high peaks of a year and six months short period varieties. And low peaks of 2.2 years and 7 months period, tell us that the short period aerosol varieties should be relative with season changes, the long period aerosol varieties may be relative with the El Nino and La Lina period. 近年來,大陸沙塵暴侵襲台灣的情況日趨嚴重影響。本研究中收集了近十年來懸浮顆粒資料,配合環保署空氣品質監測站、中央氣象局所觀測的資料與美國太空總署的衛星影像資料及NASA航空資源實驗室的氣流軌跡回推圖,希望能夠在早期觀測時發現大陸地區沙塵暴訊息,和沙塵暴所帶至大氣中的懸浮顆粒可能傳輸路徑。發生沙塵暴侵臺事件的季節,主要在春季及秋冬兩季交替期間發生的次數為最多。由地面天氣圖表、氣流軌跡回推圖及美國太空總署的衛星影像進行綜合比對之後,可大致瞭解大陸沙塵可能的移動路徑與大氣環流特徵有關。 聖嬰現象(El Nino)發生時,侵襲臺灣的沙塵暴次數會減少。在「反聖嬰現象」(La Lina)發生時,侵襲臺灣的次數相對增加。經由頻譜分析中得知,懸浮顆粒高峰期的變化有1年期及6個月變化趨勢,懸浮顆粒低峰期的週期變化有2.2年與7個月的變化趨勢,顯示短週期大氣懸浮顆粒變化應與季節變化有關,長期性變化或許與聖嬰反聖嬰週期有關連。

智慧型日光燈節能系統

本研究以增進日光燈管使用效率為目標,設計出一套整合型的系統以減少不必要的浪費。我們將感知用的硬體設備與自行開發的軟體程式作結合,使系統能夠在感知到日光燈管的各種狀態後,做出相對應的處置。其狀況包含:1.無電時系統會警告,以避免誤判的情形;2.有電時燈管正常運作;3.有電時燈管閃爍或不亮,此時系統會切斷日光燈管的電力,並記錄資訊。以上述系統為基礎,我們搭配紅外線模組來達到有人在才開燈,無人時自動斷電;亦加入偵測環境用的光敏電阻來達到光線暗時才開燈,光線亮時會自動斷電。依據測試,閃爍的燈管會比正常燈管多消耗30%的耗電量,壞掉不亮的燈管亦會消耗正常燈管70%的耗電量,對能源越來越少的今天,我們的系統提供了另一種節能的機制。

電位式茶品發酵度探針

茶品的發酵程度對其香氣與口感有決定性的影響,然而業界卻缺乏相關的客觀指標與其有效的量測方法。茶品發酵的主要化學過程是其兒茶素的氧化與聚合,這些茶單寧將隨著發酵過程逐漸由還原態轉變成氧化態。所以,不同發酵程度的茶,其氧化態單寧與還原態單寧的比將有所不同。這個比值預料可由氧化還原電位間接地量測得知。本研究使用白金絲與銀/氯化銀參考電極為電極對來量測此氧化還原電位。量具則使用具高輸入阻抗(大於十億歐姆)的pH 電極用電位計以取得茶汁中微弱的氧化還原電位訊號,可於十秒內取得高再現性(相對標準差小於3%)的電位訊號所得到的電位訊號與發酵程度呈高度的線性相關(相關係數大於0.9)。Degree of fermentation is pivotal for the aroma and the aftertaste of tea, but an objective scale and efficient evaluating methods are demanded for the important quality factor. Oxidation along with the polymerization of catechins is known to be the major chemical process during tea fermentation; the tea tannins will gradually change from their reduced forms to their oxidized formats. As the consequence, the ratio of oxidized tannins to reduced tannins will differ with the extent of fermentation. The ratio can be measured simply by the redox potential. In the present study, we used a platinum wire and an Ag/AgCl reference electrode as the electrode pair to measure the redox potential. A pH meter with high input impedance (over Giga ohm) served as our voltmeter for the weak voltage signals retrieved from tea infusions. The measurement was quick (less than 10 second) and with good reproducibility (CV0.9).

鈦鈦相傳-以新穎水熱-化學電池法製備二氧化鈦

In our experiment, the novel hydrothermal-galvanic couple method is used to produce nanostructured TiO2 thin film. Compared with the traditional hydrothermal method, whose process is conducted under high temperature and high pressure, the hydrothermal-galvanic couple method is a thermally and electrochemically driven process. The titanium atom is gradually oxidized on the surface driven by potential difference, and eventually become nanostructured TiO2. The advantages of the hydrothermal-galvanic couple method are numerous: they are simple, environment-friendly and energy-saving. Experimental parameters include time, concentration and types of solution. The hydrothermal method is used for comparison. By the cross-section and surface pictures of Field-emission scanning electron microscopy (FE-SEM), we can clearly observe that there is obvious change on the titanium surface, along with increased thickness and altered surface structure. The film of hydrothermal-galvanic couple method is thicker than that of hydrothermal method. Thickness increases with time and concentration as well. Both the hydrophile and decomposition of methylene blue examination indicate that the product on the surface contains photocatalyst-like feature.我們利用新穎水熱-化學電池法製備奈米級二氧化鈦薄膜。相較於一般傳統水熱法高溫高壓的製程,水熱-化學電池法結合了熱能與化學電能,讓鈦原子在電位差的驅動下於表面逐步氧化,最終形成奈米級二氧化鈦粒子,具備簡易、環保、省能的優點。實驗參數包括時間、濃度、溶液種類,並以水熱法作為對照組。由FE-SEM 橫截面圖及表面圖可清楚看到鈦的表面有明顯變化,膜厚增加、表面結構改變;以水熱-化學電池法所得的薄膜明顯較水熱法厚,而其厚度隨著濃度及時間的增加也有增加的趨勢,由試片親水性測試與亞甲基藍吸光度測試,皆顯示試片的表面產物具有類似光觸媒的性質。

嘗試從小鼠胚胎幹細胞培養成生殖細胞

許多難纏的疾病,如神經退化性疾病與糖尿病,在1998年建立人類的胚胎幹細胞後,開始露出一線曙光。但就算科學家已經從胚胎幹細胞,成功引導出特殊種類與功能的細胞,預備做細胞治療時,需透過細胞核移植技術,使排斥的情形大大減少。所以當今年3月,韓國透過細胞核移植技術成功作出人類的胚胎幹細胞株時,轟動全世界。但是,他們從242顆卵,只做出一個胚胎幹細胞株,浪費這麼多卵子就牽涉到醫療倫理的層面了。既然,每一個人都要訂製自己的幹細胞株,那麼卵子的來源就很重要了。理論上,胚胎幹細胞可以分化成所有細胞與組織,當然也應該含生殖細胞在內。去年5月底,賓州大學就利用小鼠胚胎幹細胞,體外培養出型態上非常像卵子的細胞。所以,今年暑假利用兩個月時間,有個機會參與了台大醫學院婦產科的胚胎幹細胞研究團隊,稍稍瞭解了胚胎幹細胞製造成生殖細胞的過程。我們採取一種方法,先從胚胎幹細胞株,用類胚胎體(EB)的立體環境,加上 SSEA-1的篩選,與維他命A的刺激,引導至初始生殖細胞,第二步利用細胞重組的方法,利用小鼠胚胎的性腺組織,來支持這些選擇過的細胞,希望可以培養出小鼠的卵子或精子。我們從EB得到SSEA-1細胞約為全體細胞的10%,然後經過維他命A的刺激,得到SSEA-1細胞約為全體細胞的5%,這時的細胞理論上是初始生殖細胞 (PGC),但是之後的體外單獨培養或與胚胎性腺重組培養,發現成果並不是很理想。到最後,也許受限於時間還有能力,沒有得到明確的小鼠生殖細胞,但是過程中,我學習到生殖細胞的生理,胚胎幹細胞的特性,基本實驗室的細胞培養與組織染色,這些都令我印象深刻。我們認為,如果有一個適當的基因轉植的胚胎幹細胞株,例如GFP放進生殖細胞相關的基因裡頭,讓達到終點,或邁向目標的細胞群,可以自我顯現,實驗會更容易達成目標。Scientists discovered ways to obtain or derive stem cells from early mouse embryos more than 20 years ago. Many years of detailed study of the biology of mouse stem cells led to the discovery of human embryonic stem cells in 1998. Through years of experimentation scientists have established some basic protocols or "recipes" for the directed differentiation of embryonic stem cells into some specific cell types. One major problem that must be solved before human stem cell therapy becomes a reality is the threat of rejection of the transplanted cells by the host's immune system. One way to avoid the problem of rejection is to use stem cells that are genetically identical to the host. This could be achieved by the same techniques of somatic cell nuclear transplantation (SCNT) that produced Dolly. Low efficiency less than 0.5% (1/242) in Korea this March brought some controversies in ethical issues. Where and how to procure the large amount of oocytes that will be required? One source of eggs could come from the generation of oocytes from embryonic stem cells (ESCs), as described by Hubner et al. (2003) in the mouse. By the selection of primordial germ cells (PGCs) and re-aggregation with their stromal cells, we hope to derive mature germ cells such as oocytes and sperm from ESCs in this study. In this study, we have demonstrated some PGCs after sequential selection by SSEA-1 antigen and optimal culture conditions. We also proved some FE-J1 positive cells but no further fertilization was obtained after all. Further investigation about this mechanism may be needed to derive these germ cells from ESCs.

愛玉愛在結凍時~揭開愛玉神秘面紗

本研究源於暑假製作的愛玉沒有結成像果凍,因此,進行影響愛玉結凍的研究。結果如下: 一、愛玉的種子夾雜一些碎屑,碎屑可以結成愛玉凍。 二、奮起湖愛玉種子,產生的膠質面積最大,野生的愛玉種子,產生的膠質面積最小。 三、熱水讓愛玉凝膠物質產生快,因而熱水結凍較快,冷水較慢。 四、逆滲透水可以讓愛玉子結成凍,推測愛玉碎屑具有離子。 五、攪拌太快或太久,愛玉中的抑制物質產生,導致無法結凍。 六、真假愛玉分辨:碘液試驗法,假愛玉遇到碘液會變成藍黑色,真愛玉黃褐色;透光度法,假愛玉透光度較大,真愛玉透光度較小;軟硬度法,假愛玉較硬,真愛玉較軟;加熱法,假愛玉加熱後融化成液體,冷卻後又凝結成凍。

嘖目稱奇的大豆卵磷脂

本研究目的是探討大豆卵磷脂對於老化及學習記憶能力是否有改善之功能。以 24 隻 SAMP8 小白鼠,分為大豆卵磷脂組及對照組,飼養 8週。經由主動迴避試驗、單次被動迴避試驗,測其學習記憶能力;另測量其腦部丙二醛(MDA)之含量,評估其老化的程度。由實驗結果顯示,在主動迴避試驗中,大豆卵磷脂組被電擊次數有減少趨勢;在單次被動迴避試驗中,大豆卵磷脂組停留在明室的時間高於對照組。而在 MDA方面,大豆卵磷脂組腦中MDA含量低於對照組。由上結果推測大豆卵磷脂對於抗老化及學習記憶方面都有改善的功能。 The purpose of this research was to study the effects of soybean lecithin on improving the aging process and learning and memory abilities. The first part of the experiment is to raise 24 SAMP8 mice eight weeks, and divided them into group A and Group B. We tested them memory power by Active shuttle avoidance test and Single-trail passive avoidance test, and tested their degrees of the aging by the content of MDA. The result demonstrated that there was a decreasing tendency in times of being hitting in group A during Active shuttle avoidance test. The time which group A stayed in the bright room was higher than group B during Single-trail passive avoidance test, and the content of MDA in group A was apparently all less than group B in the experiment of MDA. So we can get the message that Soybean Lecithin has the improvement of ameliorating the speed of oxygenation and increasing memory power.

以「亮」取勝—探討如何辨識環境中的塑膠微粒

使用尼羅紅螢光染劑對已知的1至7類塑膠染色,我們測試條件下,98無鉛汽油為溶劑、波長365nmUV光照射、(22微米)500目不鏽鋼網當濾材,可以得到最佳辨識率。若濾材微濕就進行尼羅紅染色,會降低螢光偵測塑膠微粒的靈敏度,塑膠樣品染色後靜置的時間愈短辨識率愈高。來自環境的塑膠微粒和非塑膠有機物,即使不染色,當受UV光照射時也會發出較微弱的螢光,但是顏色有差異,可使用簡單的濾光片分辨出過濾環境樣品中的塑膠與非塑膠,解決尼羅紅染色對自然界中有機生物欠缺分辨能力的困境。解析海砂中的塑膠殘留量發現:距離海水愈近殘留量愈高,此趨勢和海砂的顆粒大小較無關聯。表層海水中的塑膠微粒數量驚人,3185/1000ml,大約是溪水和雨水中塑膠密度的3〜10倍。

顆粒體對流現象之探討

漩渦之美

我們常可以在自然界中發現漩渦的存在,但其存在的形體與性質也不盡相同,為了研究漩渦的結構與形體,筆者分析出多種會對漩渦產生影響的因素:開始放流的水而高度、放流洞口大小、有無破壞漩渦結構的阻礙、單孔落流漩渦與雙孔落流漩渦、還有流體的黏滯度對漩渦的影響, 但漩渦是一個不斷改變的流體,非常難以觀察,且自然界的漩渦也不是說出現就出現,所以必須設計一個簡易實驗器材來觀察,並用數位攝影機紀錄下來,再慢慢分析,而我們也可以在這個實驗中了解漩渦的結構,和體會到漩渦所表現出自然界的力與美的一面。‧We can always find in nature of different swirl’s forms and properties. To study the swirls, we analyzed such factors, as the beginning water level, the size of the hole, the presence of obstruction that will destroy the structure of swirls, differences between single-hole-swirls and twin-hole-swirls, and the viscosity of fluid. Because swirls change all the time, it is very difficult to observe. We designed a device .The procedure was recorded with a digital video camera and analyzed it. The study helps us understand the structure of swirls and admire the beauty of swirls.