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線上教學資源

什麼條件影響著空氣密度

愛爾蘭化學家羅伯特‧波以耳(Boyle),在1662年根據實驗結果提出:「在密閉容器中的定量氣體,在恆溫下,氣體的氣壓和體積成反比關係。」稱之為波以耳定律。 1802年給呂薩克(Joseph Louis Gay-Lussac)發表了在定壓下,氣體體積與絕對溫度呈線性關係的定律,稱之為給呂薩克定律(Gay-Lussac's law)。 根據上述兩個定律可以得到理想氣體反應方程式PV=nRT, 而n= w/m,所以PV= (w/m)RT,而w/V=D,所以可以得到Pm=DRT P:壓力(atm,大氣壓) V: 體積(L,公升) m:氣體分子量(mole,莫耳) D:空氣密度(g/L) R:理想氣體方程式常數(R=0.0821 L atm/mol*K) n:莫耳數 w:重量 m:分子量 T:溫度(K) 由公式可得到密度和溫度成反比。其它條件相同之下,即溫度升高則氣體密度下降。 所以熱空氣密度小於冷空氣的密度。 乾空氣密度是空氣密度減去空氣中水分子所佔的密度,所以在同溫同壓下乾空氣密度會比一般含有水汽空氣密度來得小。空氣的組成當中,隨地點的不同水汽佔0%~5%,一般空氣中只含有1.3%的水汽,所以溫度對空氣密度的效應遠大於水汽的影響。選項A. 熱空氣,的意思是指比乾空氣溫度高的空氣,所以熱空氣密度又比乾空氣密度小。 日常生活中利用此原理的有天燈以及熱氣球,即加熱空氣使空氣膨脹,密度下降後達到漂浮上升的能力。

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小齒輪挑戰大齒輪

這是我在小時候玩畫花圓圈的一種遊戲,起先,我認為只是畫一畫而已,但是玩久了以後,卻發現:奇怪!為什麼每一個點畫出來的圖案都不一樣?有些花瓣又尖又長,有些花瓣又圓又短,甚至還有一些畫了幾圈就開始重複了呢!於是,我就開始想研究這個奇怪的問題。

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四聯原藻(Seendesmus SP.)之繁殖與抑制的研究

因某校游泳池放水後,不數日便綠色一片,且泡沫迭起,無法游泳。取該游泳池樣水,發現這些綠色大部分是四聯原藻(Scenedes - mussP .),為解決無法游泳的煩惱,乃以嘗試錯誤的探討,尋找某種物理因子或化學因子,來抑制該藻的繁殖。

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線上教學資源

趣讀科普,昇華閱讀,活化STEM腦

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利用自製頻譜儀研究蜜蜂的發聲系統

本研究利用麥克風與相關電腦設備,結合成自製頻譜儀用以觀測多種情況下蜜蜂的聲音頻率。若將蜜蜂的翅膀加以修剪,可測得有不同的頻率,解析頻率發現「翅膀為主要發聲點,但去除翅膀仍有高頻的發聲,且有三種不同的頻率。」將蜜蜂置於不同溫度下,解析頻率得知「一定溫度範圍內,溫度越高蜜蜂發聲頻率越高,反之亦然。」幼期在胸部塗顏料使絨毛無法生長,去除雙翅後,仍有頻率相近的發聲,得知「胸部絨毛不是造成高頻的原因。」靜置5分鐘,待蜜蜂停止發聲後,剪去腳、挑弄蜜蜂會發出高頻,得知「情緒是引起高頻的原因。」將蜜蜂的翅膀加以修剪,分別放回蜂窩口,發現「同一族群蜜蜂可用發聲頻率來辨別同伴。」比較義大利蜂及中華蜜蜂,得知「在多種情況下中華蜜蜂發聲頻率皆較義大利蜂高約70Hz。」因此本實驗之結論並不受蜂種影響。The study, capitalizing on a hand-made frequency divider, the microphone and computerized equipment, observes a variety of frequency of sound given off by bees. We read different frequencies from the apparatus when the bee’s wings were trimmed. Analyzing it, we discover that the bee’s winds are major source of its sound, but it still gives out high-frequency sound when the wings were completely cut off.” After analyzing the frequency, we discover that within a certain temperature range the higher the temperature is, the higher the frequency is, and vice versa. In one experiment, we painted the thorax at its pupal stage to stop the bee from growing fine hairs. Even though the wings had been removed, it still gave out high-frequency sound. We, therefore, conclude that fine hairs on the thorax have nothing to do with the making of the sound. In another experiment, bees were placed in an undisturbed environment until they are completely silent. Then, some of the bee’s legs were cut off, while others were provoked. And all the bees make high-frequency sound in the process. We make a hypothesis that emotion could be the cause of bees’ sound-making. The bees with different trimmed wings were put back to the beehive; the bees can still recognize one another by the different sound frequencies. If we compare A. m. ligustica with A. c. cerana under different conditions, we find that the frequency from the latter is about 70 Hz higher than that form the former.

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鉤盲蛇(Ramphotyphlops braminus)捕獵四部曲

Feeding behavior is the action which animals depend on maintain livelihood. Snakes usually use the three following ways to catch their preys: winding, venom-releasing and pressing their game to death. However, previews study is rare about the feeding behavior of Ramphotyphlops braminus. This puzzles us, prompting us to do in-depth research on it. When performing an experiment, we will use the camera with infrared function to record entire experiment and the obtained data will transform the graph. Our result shows the feeding behavior of R.braminus is a new way to catch their game, and the minute process of this special way is also written down in our report. We hope that the result can let everyone be clear about Ramphotyphlops braminus of soil ecosystem status, and it is an essential contribution for building the archive of Family Typhlopidae. 攝食行為是動物賴以維生的行為。在蛇類中,常見的捕捉方式有:纏繞、 使用毒液、壓斃等三種類型。但,文獻中卻沒有任何有關於鉤盲蛇(Ramphotyphlops braminus)的捕食行為。這使我們感到疑惑,並想深入探討。在實驗進行當中,我們使用紅外線攝影機將實驗全程錄製下來,並將所得的數據轉化成圖表。而其結果顯示鉤盲蛇(Ramphotyphlops braminus)的捕食行為是一種全新的模式,這種模式的詳細過程也被我們全部收錄到報告中。我們希望做出來的結果能讓大家對鉤盲蛇(Ramphotyphlops braminus)在土壤生態系中的地位更加了解,而且對於建立盲蛇科(Typhlopidae)資料庫有實質的貢獻。

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太陽能燃料電池

近年來,「保特瓶燃料電池」,這裝置已廣泛地使用在燃料電池教學上,稱為簡易燃料電池。但這原理雖普及但仍有創意改良的空間。本實驗力致將燃料電池與太陽能作結合為研究方向,發展出能在陽光下高效能放電的環保電池。 偶然下發現炙熱的銅片急速冷卻會裹上粉紅色的氧化亞銅﹔氧化亞銅是一價銅的氧化物,具太陽能轉換潛力,故我們有了拿它來當電極的念頭,先利用外加電壓,進行可見光分解水實驗,結果照光下分解水產生大量氫氣﹔且氧化亞銅本具高活性有光電化學性質,在逆反應時容易釋放電子產生高效能放電;並且在照光增溫同時也加快了電解速率,但溫度不能太高,而照陽光的溫度正適合,故我們試著將各種變因取出並設計實驗,來驗證與討論,最後統整設計出一個能利用太陽能的環保「保特瓶燃料電池」,對環保能量再注入無限的可能與創意。

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半屏山之簷下姬鬼蛛的研究

The spiders, Neoscona nautica, often appear in groups, but individuals have their own sense of territory.They usually spin webs among branches during 6:00~ 8:00 in the evening. When building webs, they will first start with bridges and then spin Y-shaped spokes. Next, they spin meshe of net, silk frame, spokes, spirals and free-zone in order. After finishing webs, they will wait for prey on the free-zone or meshe of net. If they find something inanimate on the web, they will break the spiral attached with the inanimate object that is later removed. If the meshe of net is broken, they will fix it immediately. For them, the time to take webs back is during 2:30~ 6:00 in the morning. Most time they use the first pair and the second pair of legs to take webs back and swallow the webs. Sometimes, they break the spirals by the last pair of legs. The sequence to take webs back is : lower right section, lower middle section, lower left section, upper left section, and upper right section. At last, one thread of bridge will be left. Every early mornings they take webs back and swallow them. The next evening they rebuild webs. Possibly there are two reasons to explain why spiders eat their webs: (1).They swallow webs to get protein. (2).The web threads are easily polluted by dust and humidity and reduce stickiness. The web may also reduce the probability of capturing prey. The body length of them is not related to effective web dimensions. However, the web sizes depend on the width of web-building location. The study shows linear relation among body length, meshe of net and dimensions of free-zone. The linear relation represents that the meshe of net and free-zone have ecological or survival meaning for them. We expect that this study of Neoscona nautica can be helpful to build spider ecological database in Taiwan.簷下姬鬼蛛常成群出現,但個體卻有很強的領域性;常於下午6:00 至8:00 結網於樹枝間,結網時,先以橋絲為出發,織出一Y 形的縱絲,再由此依序織出中空網眼、絲框、縱絲、橫絲、棲息圈,網結好後,簷下姬鬼蛛則在棲息圈或網眼靜候獵物,若發現網上有非生物之異物,則將黏住異物的橫絲弄斷,再把網上的異物丟棄;若網眼被破壞,則會立即修補。收網時間為凌晨2:30 至凌晨6:00,收網時,大部分由第一、二對步足進行收網,偶爾會用最後一對步足將橫絲弄斷,一邊收網一邊將網吞食,收網的順序為:右下、中下、左下、左上、右上,最後留下一條橋絲。簷下姬鬼蛛每天清晨都會收網,並將網吃掉,翌日傍晚再重新結網,其可能原因有兩點:(1)將網吃掉以補充蛋白質。(2)蛛絲容易受灰塵、水氣之污染而減小黏性,降低獵捕功效。簷下姬鬼蛛體長與有效網面積無關,但網的大小視其結網地點寬敞程度而定。體長與網眼、棲息圈面積呈線性關係,表示網眼和棲息圈對簷下姬鬼蛛具有生態或生存意義。我們對簷下姬鬼蛛生態調查之結果,希望能幫助台灣的蜘蛛生態資料庫之建立。

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太陽能攜帶式充電器

太陽所產生的光和熱,是帶給地球多采多姿生態的原動力。因為有太陽源源不斷的向地球傳遞能源,植物才得以進行光和作用,將太陽能轉換為自身的養分。而動物再藉由攝取植物,從而得到自身活動所需之能源。所以太陽能可以說是地球上一切生命的基礎。近代環保意識的高漲,使得傳統的火力發電廠與核能發電廠受到嚴格的批評。如果我們加以追根究底,現今的發電廠,除了核能發電廠以外,都可以看做是將既有的太陽能轉換出來而已。聰明的人類很快就想到,既然現在所使用的能源大部分都來自於太陽,那我們為什麼不直接向太陽要能源呢!而這也就是現今太陽能發電的構想。而目前直接轉換太陽能的方式不外有:收集熱能與轉換光能。以收集熱能來說,小規模的民生利用方面,如同現今經常看到的太陽熱水器。較大規模方面則有所謂的集熱式太陽能發電廠,藉著集中太陽能所產生的高熱來使水汽化產生蒸汽,進而推動渦輪發電機產生電力。

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傑克船長的心機

傑克船長和他的海盜們掠奪到許多箱珍寶,每箱含有數量不等的金幣及鑽石。船員們深怕傑克船長又出什麼陰謀,一致同意讓船長任選一半的箱子拿走。\r 當然,傑克不知道金幣和鑽石的價格比,為了保證可以得到一半的利益,傑克希望他拿到的金幣和鑽石都各占一半。傑克的願望會實現嗎?\r 這個問題已用高等數學證明其解,而本研究利用初等數學的方法,除證明傑克需取的最少箱子數外,同時也能更快速的算出取法。\r 類似的結果可應用至分配災區物資等情形,或任何無法轉移、獨立的資源,如各式專長的人才、多功能的機械等,期望可對更有效的分配做出貢獻。

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大「撤」大「霧」-防霧探討與應用

在這次的防霧實驗中,我們調查了家鄉漁民常用的防霧方式、澎湖常見植物的防霧效果與探討日常常見的防霧妙方。從簡易測試與透明度分析儀的結果來看,我們發現天然防霧塗料對「玻璃」能有效的防霧,但是對「壓克力」材質的介面並沒有明顯的防霧效果;日常的化學防霧材料對兩介面都有不錯的防霧功效。

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Remote Activated Chip-Based Drug Release System Using Nanoparticles as an Anti-Cancer Therapeutic

The pharmaceutical industry is constantly searching for methods that allow drugs to be delivered as a direct response to a specific stimulus, in which the locus of delivery is in the vicinity of required region. A unique thermo?reversible hydrogel,F127 modified with dimethacrylate (DMA), that can deliver drugs at physiological temperatures was synthesized. Nanoparticles which are specific for targeting human body cancer cell were absorbed by this hydrogel. The toxicity of nanoparticles with different diameters and coating was measured using the MTT assay. It was found that nanoparticles with smaller diameters and folate coating were most toxic to the cancer cells. The release rate of the nanoparticles from the hydrogel was measured as a function of temperature with the hydrogel releasing approximately 3 L nanoparticles per hour. Exposing this drug delivery system to cancer cells would effectively inhibit MCF7 cell proliferation. By grafting this nanoparticle?loaded hydrogel onto a thermoelectric module, the release of the drug would be controlled. Thus, a successful temperature sensitive hydrogel was synthesized that releases cancer?targeting nanoparticles which inhibit cancer cell proliferation, thereby engineering a controlled drug delivery system.

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