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符合畢氏定理X12+X22=X32的正整數解(X1,X2,X3)我們稱為三元畢氏數;符合N元不定方程式X12+X22+⋯+Xn-12=Xn2的正整數解(X1,X2,⋯,Xn-1,Xn)被稱為N元畢氏數。本研究更正陳揚叡同學在台灣2008國際科展中對N元不定方程式X12+X22+⋯+Xn-12=Xn2所提出的N元畢氏數一般解,並利用對圓點方陣的降階分奇偶數組加以探討,其中,奇數組是在(M+1)階方陣中透過一次降一階來探討三元畢氏數中X1=2k+1的情況,而偶數組是在(M+2)階方陣中透過一次降二階來探討三元畢氏數中X1=2k+2的情況。在獲得初步的成果後,又藉著直角三角形的擴充依遞迴定義的方式來進一步來探討N元畢氏數。最後,我得到N元畢氏數(X1,X2,⋯,Xm,⋯,Xn-1,Xn)的關係式(表一)。
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前年的九二一集集大地震,慘痛的經驗都讓我們記憶猶新。因為停電全國幾乎都?罩在黑暗之中,電池成了最熱門的搶手貨; 價格當然水漲船高,居高不下!可能是平常的二、三倍,至還可能有錢買不到呢!災區的人們更可憐,不但停水還斷電,沒有電~他們幾乎與外界隔絕,生活變得非常不方便,簡直是寸步難行;而電池在此時,更凸顯出它的重要,但是停電時,不一定家家戶戶都有儲備電池;於是我們便想:利用日常生活中,隨手可得的物品,製做成簡易且實用的電池; 如此一來,就不必害怕沒有電池了!在各界極力倡導資源回收的同時,3R:Reduce' Reuseu及Recycle還清晰地印在腦海中,某日,喝完飲料後正準備鋁罐壓扁丟入回收筒時,突然靈光乍現~為什麼不利用廢鋁罐製作電池呢?況且,現在全球正值能源危機,油品沒幾天就漲價一次,工業發達使石化燃料及各種原料的消耗劇增,研發新能源與廢棄物的回收再利用,就是我們刻不容緩、責無旁貸的課題
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科展作品檢索
微陣列基因分析法探討心肌細胞在機械性展延下的基因表現
高血壓所誘發的機械性展延是造成心肌肥大的基本因子,本實驗即藉由微陣列基因分析法同時大量的分析機械性展延所造成心肌細胞的基因表現。將新生鼠的心肌細胞施以 20﹪的機械性展延,抽取其 mRNA製作成 cDNA 探針與現成的 cDNA 晶片進行雜漬反應 (此晶片上包含了 480個如訊息傳遞、控制細胞生長週期、細胞骨架等的已知基因),在眾多有因為機械性展延而造成基因表現差異的基因中,我們選擇了 eNOS 基因(內皮細胞 NO合成?)進行西方墨點法及 NOS活性和 NO 產生量測定的實驗,進一步證實 eNOS 的基因表現量的確是增加的,此一結果與微陣列基因分析所得之結果不謀而合。 Mechanical stretch induced by high blood pressure is an initial factor laeding to cardiac\r hypertrophy. The use of cDNA microarrays has made it possible to simultaneously analyze\r stretch-induced gene expression in cardiomyocytes. Neonatal rat cardiomyocytes were cultured on\r malleable silicone dishes and were stretched by 20%. We compared the transcript profiles of\r cardiomyocytes under mechanical stretch for 60 minutes by hybridization of cell-derived cDNA to\r DNA probes immobilized on microarrays. The microarrays contained probes for 480 known genes\r including signal transduction, cell cycle regulators, cytoskeleton and cell motility, and so on. Eighteen\r genes were indentified that showed significantly differential expression in response to mechanical\r stretch in cardiomyocytes. Of the represented genes expressed, endothelial nitric oxide synthase (eNOS)\r genes was the most interesting one. Northern blot and western blot analysis further quantified the\r expression of eNOS gene. Mechanical stretch also increased constitutive NOS activity and NO\r production. Our results indicate that mechanical stretch induces eNOS gene expression thus increases\r constitutive NOS activity and NO production in cardiomyocytes.
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台灣水庫淤積問題相當嚴重,總淤積量約蓄水容量的17.44%,高達479,000,000m3,並持續淤積。而當清除水庫淤泥時延伸出的淤泥棄置問題及工程棄土問題,我們擬定一種加勁磚,以淤泥或工程棄土為主要填充材,添加第一型水泥為黏結材,加入適當水量可製成景觀磚,但因土體強度不足,而透過天然植物及環保回收料作為加勁材,藉此強化其抵抗外力之能力,達到減少淤泥或工程棄土問題兼具資源再生之功效。研究目的為探討使用淤泥或工程棄土,添加兩大類加勁材(天然、環保類),研究加勁材對土體之抗壓、抗拉及抗折強度提升率之影響因素。經實驗模擬後,發現水泥添加量(W/C=2.0↓)與養護齡期(7天↑)為強度提升率之主要因素,而土體之握裹力以纖細加勁材具有最佳強度提升率。
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科展作品檢索
Powerless Shack Cooler
Purpose of Project: To save energy and to help the underprivileged with a cooler that uses no electricity to make their lives better. Procedure/method followed: STEP 1: Collected 28, used, 2 litre plastic bottles. STEP 2: Chose the window with the best wind flow. Measured the size of the window and the room chosen. STEP 3: A sturdy thick polystyrene board was cut to the size of the window. Holes were drilled to the rim size of the bottles spacing them according to the body size of the bottles. STEP 4: Bottles were cut in half. STEP 5: The bottle necks were slid through the holes with the necks open to the inside of the room and the bodies open to the outside. STEP 6: Fixed a thermometer in the room and measured the temperature and recorded it. STEP 7: Fixed the Powerless Shack Cooler with the necks of the bottles open to the inside and the bodies open to the outside of the room. STEP 8: The temperature variation was checked and recorded every 30 minutes for 3 hours. STEP 9: Another room of the same size and window was also chosen. Fixed a thermometer and temperature variation was checked and recorded every 30 minutes for 3 hours. This served as the control of the experiment. Data/results: The room temperature decreased over time inside the room where the Powerless Shack Cooler was installed onto the window. But the control room maintained the initial room temperature although slight fluctuations in the room temperature were observed over time. Conclusion: The hypothesis was supported. As the air molecules moved through the bottles, it bounced off each other, and off the walls of the container, holding the air. A small volume of air passed at a high velocity. When the molecules moved faster the collision became more often. These collisions and the push increased air pressure. When the container’s space was getting smaller, the molecules picked up speed and the temperature went up. When the air was released out into the room, the volume suddenly expanded. The intermolecular spaces became larger; so less agitation and vibration of molecules took place. The molecules moved slowly. The room temperature reduced. Air inside the room became cooler. During the adiabatic expansion, air molecules used heat energy from the room and converted it into kinetic energy for faster movement.
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線上教學資源
如何由外觀簡單辨識火成岩和沉積岩呢?
火成岩係岩漿冷卻凝固所形成。在岩漿冷卻的過程中,熔點高的礦物先結晶成形,熔點低的礦物較慢冷卻,在剩餘的空間中結晶,因此會形成礦物彼此鑲嵌的岩理。沉積岩主要是陸地上各種岩石受到侵蝕之後,被流水搬運到海底層層堆積,所以會形成一層層的層理,組成顆粒因為經過長時間搬運、良好的淘選而變得圓滑且大小相當。 結晶明顯,色彩艷麗的火成岩,如花崗岩,是良好的石材,經常被裁切成石板,用於鋪設室內地板或戶外牆面。沉積岩若膠結不佳,顆粒容易剝落,如砂岩,多用於鋪設步道,或切割成磚型,作為建築外牆。
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前天林伯伯送來一盒林姐姐的訂婚喜餅,餅上滿是小螞蟻,連盒搖了半天還是沒有弄乾淨一一螞蟻真是討厭。第二天我到學校也聽幾個同學說:「放在櫥裹的糖也常跑進螞蟻。我們想如果有簡單的方法能避免螞蟻來偷襲及能知道有關螞蟻的生活情形和種類等,那多好,因此就請教級任鄭表師,老師說:「這問題很好,讀我們一起研究吧!」
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我們利用家庭裡常見的廢棄絲襪,將之回收再利用。絲襪中的耐綸成分可溶於甲酸,經純化、脫色後即可得到耐綸溶液。我們將耐綸溶液均勻滴加於玻片上風乾,得到自製薄板層析試片(TLC片),可運用於生物及化學實驗中混合物的分離。分離後的物質亦可通過儀器做定性及定量分析。 耐綸的化學結構含有醯胺鍵,我們從早期的科展報告中發現重金屬鹽類易與蛋白質結合成穩定的沉澱物而析出,得知蛋白質因含有大量醯胺基團,能與金屬離子結合成蛋白質鹽沉澱,藉以除去水溶液中的重金屬。我們利用同樣含有醯胺鍵的自製耐綸溶液進行重金屬吸附實驗,期望能夠達到吸附並除去重金屬的效果。本實驗所使用的材料是家中舊有的尼龍絲襪,以達到廢物利用及環保的最高宗旨。
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全球石油半數以上蘊藏在新生代(即最近的地質年代,距今約7000萬年前)的岩石中,古生代(2億3000萬~6億年前)岩石居第二,接著是中生代 (7000萬~2億3000萬年前)的岩石之中。石油的生成過程要經過千萬年,所以消耗量大於石油的生成必定會有消耗完的時候。目前世界各國都在研發新能源,即再生能源例如太陽能、風力、地熱、潮汐能或生質能等等,以減少對石油的消耗量,更可延緩未來一百年內石油用完的危機。\r 目前石油探勘與開採技術都比過去進步,降低開採成本,因此可對更深於地表的油田進行開採,所以在未來一百年內還是可以繼續使用石油的,但是隨油田枯竭、開採難度與成本提升,會造成石油價格逐步走揚。\r 石油只要在適當地點無時無刻都會生成,但是要達到可開採的經濟價值,過程是緩慢的需耗時千萬年。
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在綠色能源中太陽能的利用充滿了無限的機會,其中利用太陽熱能發電的太陽能煙囪觀念有很大的潛力。在本研究中,我們以實驗的方法討論煙囪高度、入風口大小、管型等因素對solar chimney 效益的影響,發現就原先的觀念設計中,有相當大的改進空間。整體實驗而言,所改變的各項變數中,以管型之改變有最大的改進效益。就同長度直管與漸擴管而言,漸擴管在風速上有明顯改進效果,且以流速與截面積換算成效率,較原直管設計之效率高出約20 倍,因此推測漸擴管應用在現行之solar chimney 以改進效能是極有可行性的。研究中也發現煙囪管壁的熱傳導也會影響氣體的總體流動,使效率降低。相信此實驗之數據對日後嘗試對solar chimney 進行改進的研究者有相當之參考價值。Solar energy has a great market potential among many clean energies. The new solar chimney concept using solar thermal power in power generation may have a bright future. Experimental work was performed to study the energy conversion characteristics of a solar chimney. The air moving capability and the influences of chimney height, the shape of chimney and air entrance dimension were studied. It was found that there is a great room to improve the current solar chimney design and thus the efficiency. Overall speaking, the chimney pipe geometry may have the most significant impact on the improvement of performance. A diverged pipe configuration can induce nearly 20 times more flow than a traditional straight pipe. Another finding is the heat transfer effect on the chimney pipe may have the effect in reducing the flow. It is believed that the present study0 is valuable for those people in designing a future solar chimney.
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我們去率芒溪走走時,看到許多有刮痕的石頭,於是我們把它們帶回去研究。石頭上的刮痕有的都是朝同方向,有的沒有規律,石頭上還有分層,是泥沙一層層堆積形成的。我們用彩色膠泥、陶土、麵糰來模擬地層,還設計了沖水實驗,結果大石頭停留在河道附近,較小的沙子就被沖得較遠,形成一個斜坡。我們還發現有交叉的和沒交叉的刮痕;和分層同方向和不同方向的刮痕。另外利用陶土模擬石頭,進行石頭裂痕的實驗,結果發現和撿回來的石頭裂痕有些很相似;也利用兩條木塊夾住鹹糕、甜糕擠壓,結果造成糕餅的裂痕和彎曲,和野外看見的一些地層相似,我們終於知道石頭裂開的原因。
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科展作品檢索
遠離“干擾”與 “飄浮”─汽車擾流板之探討
學校的停車場停了十幾輛的轎車,其中有幾輛轎車的後車廂蓋上多裝上一片顏色和車子一樣的橫桿,我覺得很奇怪,請教老師,老師說這個東西叫做擾流板,它可以減少氣流對行駛中的車尾的干擾力量,也可以使行駛中的車子更為下沈,我聽了以後滿腹的疑問:流經車體的氣流怎會對車尾有干擾的力量呢?擾流板真能減少干擾的力量嗎?還有擾流板真能使行駛中的車體更下沈嗎?如果可以,那麼,怎樣安排方式的擾流板,才是最有效果呢?多寬?多高?什麼角度?什麼位置最恰當呢?為解決這些疑問,我們在老師的指導下,做了這一個研究。
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