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科展作品檢索

天使的眼淚

水晶土,又稱水晶寶寶,可吸收相當於自身重量幾百倍的水,我們發現,它的膨脹和浸泡的水質有很大的關係,尤其是含有鹽份的水。目前應用在衛生用品,如嬰兒尿布,尿液中含有鹽份,水晶土一旦吸收了,膨脹的程度並不會太大,符合使用的原則。據本實驗結果發現,將水晶土作為保冷劑可以方便的利用在生活上許多地方,當我們發燒或中暑時,可以把它敷在額頭上,也可以用來保存食物,夏天時,可以利用保冷劑讓自己涼快。將水晶土作為精油香包,大約可以維持三天到七天,而樟腦油香包可以驅蚊,又方便攜帶。將水晶土作為除濕劑,可讓鞋櫃及衣櫥保持乾燥,減少鞋子及衣物發霉,和一般除濕機或市售的除濕劑相較,比較具有經濟效益。

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線上教學資源

衛生紙也能滅火嗎?

因為火小,當衛生紙登平平的蓋下時,燃燒的棉花棒附近,缺少空氣(氧氣),所以火會熄滅!

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察顏觀色有一套,酸鹼『光』看就知道

水溶液在廣用試劑檢驗下會呈現不同的顏色,根據顏色變化可判斷水溶液的酸鹼性質及強弱,但有時顏色相近不易比對,色盲或色弱的人甚至無法辨別色系。利用我們實驗出的廣用指示劑與待測溶液的比例檢驗,再配合自行研發的『光電池酸鹼計』,可將不同pH值水溶液所呈現的顏色予以量化,不僅可判別水溶液的色系來『快篩』水溶液的性質,亦可依水溶液顏色的深淺進而判斷其酸鹼性質的強弱。最後我們設計出【pH值-顏色-電流值】對照表,讓我們所設計的『光電池酸鹼計』在使用時更加方便。

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“氮”憑本事-土壤中單棲固氮細菌族群比例及親緣關係探討

Azotobacteraceae 為一單棲固氮菌科,包含Azotobacter 與Azomonas 兩菌屬,在農業上可用來改善缺氮的貧瘠土壤。在分離土壤中的Azotobacteraceae 時,發現非單棲固氮菌與單棲固氮菌間可能具有共生的情形。我們利用優勢培養(缺氮)的方法篩選土壤中的Azotobacteraceae,將優勢培養後所生成的菌落稀釋104~106倍後,能有效分離Azotobacter 與Azomonas,然而低於此稀釋倍率則會形成混合菌落,其中可同時發現單棲固氮菌與非單棲固氮菌存在,推測某些非固氮菌在優勢培養過程中可能可從單棲固氮菌獲得氮源,與之共生。此外亦從菌種形態的差異並配合顯微螢光雜合技術(fluorescence in situ hybridization, FISH)、分子遺傳標記(16S-rDNA)等方式,分析土壤中的Azotobacteraceae,探討單棲固氮菌及其他非單棲固氮菌在培養基上的生長情形、比例及親緣關係。The family Azotobacteraceace is group of free-living nitrogen-fixing bacteria that is found in soil. Two genera are within this family: Azotobacter and Azomonas. Agriculturally, it is often used to improve fertility for nitrogen deficient barren lands. We analyze the Azotobacteraceace according to molecular biology and traditional taxonomy. We used an enrichment procedure to culture the bacteria, and diluted it repeatedly. We found it most suitable to dilute it 104~106 times to best separate Azotobacter from Azomonas. If the concentration were to be higher than this, mixed flora containing many different bacteria species would be found. Moreover, we noticed that non nitrogen-fixing bacteria, symbiotic nitrogen-fixing bacteria, and free-living nitrogen-fixing bacteria would form a single colony on a nitrogen-deprived medium. This implies that a symbiotic relationship may exist between nitrogen-fixing bacteria and non nitrogen-fixing bacteria. We also discuss the growing situation, the group proportion, and the relationships between free-living nixtron fixing bacteria and other bacteria by morphology, fluorescence in situ hybridization (FISH), and molecular biology.

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以重力驅動之微流道細胞分離器

本研究利用一種不需藉外加幫浦,以重力驅動即可自行使液體流且形成層流的系統。因微道尺寸夠小,足以形成層流,再由中入口、出口儲液槽的高度差、毛細現象以及表面張力,驅動流道中的液體、形成流速穩定的層流。由層流的性質得知,死菌只能隨流層前進,而因活菌有運動能力,能自分布於系統中,如此便可將死亡及活力較差的大腸桿菌從中分離,並探討各種影響細菌分離的機制。

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Development of an Inexpensive Raman System and a Littrow Spectrograph

「風笛」是台灣原住民鄒族的信號用具及祈雨法器,由一條繩子綁一支竹片構成。轉動風笛時,竹片會繞繩子自轉並拍打空氣而發出聲音,並有上下飛舞的現象。 \r 風笛產生聲音的原因,為竹片拍打空氣而造成的渦流共振現象;又由於繩子扭力大小及方向改變,使風笛的音調忽高忽低、響度忽大忽小、且竹片會在兩個平面上公轉,而有週期性變化。 \r 施力使風笛公轉轉速加快時,竹片自轉速率也變快,使其音調愈高、響度愈大;而繩愈短、愈粗時,竹片的公轉週期將愈短。

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東方帆船推進原理探討

本文研究風洞中之風帆在不同條件下,受風吹拂所產生之升力與阻力關係,並探討及成功 的以數學模型解釋其原因,此研究結果可應用於帆船帆面之設計。其主要探討之變因為以下 之五種: (一) 風速大小對帆船帆面之受力關係:當帆面與風向垂直時,在低風速時,實際測值較接近 風速的一次方的函數關係。高風速時,實際測值接近為風速的二次方的函數關係。 (二) 帆面積大小與受風推進力之關係:當帆面與風向垂直時,在風速固定風速下實驗,得到 面積與風對帆推力成正比。 (三) 順風航行時,帆面之攻角(θ)與受風推進力之關係:航行方向的力與sin 2θ 成正比關係。 (四) 側風航行時,帆面之攻角(θ)與受風推進力之關係:帆面在攻角大於 45°時,航行方向的力與sin θcosθ 有相當程度的吻合,而在攻角0°~45°之間則與飛機攻 角升力資料相接近。 (五) 初步探討雙桅帆與單桅帆面受風推進力之不同:發現其在側風時能有效的減少失速的現 象,在帆面高攻角時,能減少失速現象,依然可以持續穩定的航行,我們也可推想出飛機 的機翼前段的縫翼功能也是如此。 This article is derived from our research of relation between lifting power and its resistant power produced via wind-blow in a wind tunnel under different terms and condition, also to discuss and to explain their causes successfully via mathematics models, thus, the result of this study may be applied in designing of sail-surfaces of sails boats. Its major discussion can be included into the below 5 kinds: - Relation of (1) Relation of sizes of wind-speed against reacceptance of aerodynamic forces over sail-surface: When sail-surface and wind direction becomes horizontal, under low coin-speed, practical measured-value is rather close to wind-speed's linear function relation. When in nigh wind-speed, the practical measured-value is rather close to wind-speed's quadratic function relation. (2) Relation of size of sail-surface and pushing power of wind: When sail-surface and wind direction becomes horizontal, an experiment was made under fixed wind speed, the result obtained is sail-surface size and pushing wind power toward sail is in direct proportion. (3) When it is in “round-the-clock wise” navigation the angle of attack (θ) of sail-surface and the relation with wind's pushing power: Strength of navigation direction and sin2θconforming direct proportion. (4) When it is in side-wind navigation, the angle of attack (θ) and pushing power by wind relation; When the sail surface is in the angle of attack (θ) greater than 45o, the navigation direction power and sinθcosθhas certain extent of conformity, and between angle of attack e 0o-45o, happens to be very appropriate with aircraft's angle of attack and lifting power data. Fundamental discussion of Double Masts Sail boats and Single Mast Sail boats comparing differences of wind-aided pushing power: It was found that stall phenomena could be decreased effectively, when it is side-winded, especially, when the sail-surface is at high angle of attack, it could decrease Stall phenomena, and could maintain stable navigation. We can also assume that the front section of aircraft aide-wing’s function exactly the same.

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科展作品檢索

模「飯」生

本研究主要是研究要如何蒸出好吃的飯。一開始我們查到四種煮飯方法,但是瓦斯、電鍋煮飯的技術有點難,第一次很難成功,電子鍋煮出來的飯又沒有我們去買蒸的飯那麼粒粒分明、那麼好吃,所以我們想研究如何用最方便的方法蒸出好吃粒粒分明的飯。 研究中為了把感覺變成科學的數字,我們設計了「自製測硬度器」、「自製測黏性器」,用科學的方法來測量飯粒的硬度、黏性。 最後我們不但找到蒸出「粒粒分明的飯」最簡單的方法、利用「改變蒸的時間」就可以輕鬆調整飯的硬度;冷飯也只要短短6分鐘就可以變好吃,而且我們還利用蒸飯多餘的蒸氣幫助加熱水來煮湯,節能減碳,飯還是「蒸」的最棒!

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High Speed Size-exclusion Chromatography (SEC) Using Spherical Meso-structured Cellular Foam (MCF)

Size-exclusion chromatography (SEC) is often used to determine the molecular weights of and separate polymers and proteins. The porous packing of the SEC column effects the separation of molecules, with larger molecules eluting earlier. Interest in high-speed SEC for larger molecules has been building, especially for combinatorial polymerization reactions and online SEC-MS applications. Mechanical stability of the packing, which siliceous materials have more of than polymeric ones, therefore needs to be improved. Several silicas have been explored but limited pore sizes and pore volumes have restricted their usage to separating small molecules. Siliceous MCF templated using oil-in-water microemulsions has good potential for SEC packing because it has ultralarge pore size (20-50 nm), high porosity and sturdy skeleton. However conventional MCF consists of highly irregular particles and hence cannot be used as packing.

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線上教學資源

為什麼金屬表面要經過處理?

金屬經初步加工成型後,需要對金屬表面作美化及修飾,更進一步改變金屬表面的機械性質及物理化學性質等之各種操作過程,稱之為金屬表面處理,或稱之金屬表面加工。表面處理的目的有以下四大類:美觀、防護、特殊表面性質、機械或工程性質。金屬表面處理期中一項是為了防止金屬生鏽,目的是要隔絕金屬與氧的接觸,可以在金屬表面鍍上一層保護膜,來防止腐蝕,用電鍍、熱鍍、噴鍍等方法,在鋼鐵表面鍍上一層不易被腐蝕的金屬,如鋅、錫、鉻、鎳等。這些金屬常因氧化而形成一層緻密的氧化物薄膜,從而阻止水和空氣等對鋼鐵的腐蝕。

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會鑽洞的小工程師\n─裝死專家米象蟲的研究

有一天,我幫媽媽到米缸量米,忽然看到一種很奇怪的蟲在蠕動,我不敢量米,所以就趕快跑去找媽媽來看,媽媽看完說:「別擔心,那就是米蟲罷了」我又問:「它到底是益蟲,還是害蟲呢?」媽媽說:「我也不知道,這要你自己去觀察。」就是媽媽這番話,引起了我研究的心理。

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火災現場煙囪效應的探討

使用線香製造煙,藉由壓克力所製造公寓大樓房間及樓梯的模型,模擬火災的情形,觀察火源在不同位置,各種窗戶的開法,如何影響到煙運動,及觀察線香的燃燒狀況;觀察次同時開啟兩扇窗戶,煙的運動狀況是否會有不同,線香的燃燒情形是否改變?房間中溫度的改變,是否影響到煙的運動?

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