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本研究分析2003 至2006 年全球震矩規模大於等於6.5 之地震資料,並排除電離層垂直全電子含量(TEC)較低的高緯度地震與受太陽活動影響的地震資料,總計分析地震資料73 筆,探討震前TEC 的變化。經分析獲得的結論為:82%的地震事件,在發生前七天至少有一天TEC出現異常現象,顯示地震在發生前的確會影響TEC。岩層因不同的受力形式所引發的不同類型斷層活動,都同樣造成TEC 的震前異常。地震震源位置不論是位於陸地或海底岩層,都同樣引起TEC 震前異常,顯示TEC 震前異常不受海水阻隔影響。震源深度不同的地震,雖然岩層的物理或化學性質不同,但只要岩石發生斷裂錯動,都同樣引起TEC 震前異常。此外地震發生前TEC 異常的時間分布,越接近地震發生日,出現異常的次數愈多。
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最古老之動力機械為蒸氣引擎,在早期蒸氣火車發電機皆由蒸氣引擎發展而來,本研究即利用最古老之蒸氣引擎(俗稱飛龍引擎)之製作,以探討內燃機之基本理論以作為模型引擎設計之基礎。在飛龍引擎製作中,歷經引擎無法轉動之痛苦,並極力找尋一百年前發明蒸氣引擎之同樣思考,最後找尋到引擎啟動之合適尺寸,再用其尺寸延伸做實驗,以發展其理論,最後發現引擎設計之重要變數如管長﹑火焰﹑本身重量均為設計中重要因數,最後用正式機械設計方式完成第四代引擎亦正式運轉,可見本蒸氣引擎之設計基礎具有相當實用之基礎。The oldest locomotive engine was the steam engine. All early steam locomotives were developed from the steam engine (Heron engine) and this research project uses the Heron engine to explore the fundamental theories behind the internal combustion engine as a model for basic engine design. During the production stage of the Heron model, there were difficulties with engine rotation, and so efforts were made to find the same thought processes involved in producing the steam engine 100 years ago. The dimension appropriate for moving the engine was first found, and then the idea was extended with experimentation of the size in order to develop the theory of engine design. In the end, the length of the steam hose, the strength of flame, and the actual weight of engine were all found to be important factors of design. Finally, the fourth generation Heron engine was able to rotate properly using the proper engine design method, so it can be seen that the fundamentals of steam engine design has quite a practical engine design basis.
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“碘化鋅”產率變變變---溶劑對產率的影響
The research mainly discuss the influence on the rate of zinc iodine with different solution as catalytic agent. We use water, acid water, ethanol methanol acid ethanol, and acid methanol and so on as different solution to participate in the process of an equation: Zn+I2 → ZnI2 to work out the variation of the product's amount. Besides, we also change the proportion of Zinc and Iodine to discuss the difference between the proportion of reactant and the product's amount. The result shows that the product of this equation is ZnI2 not Zn(I3)2. Ethanol and methanol have the same effect as water to accelerate the process of the equation. We find out that this reaction get higher product's amount in acid condition. Also, put the mass Zinc with the mass iodine can get higher product's amount, Furthermore, acid in specific range (0.01M—1.00M), the denser the acid is, the higher product's amount we get. But how the water as catalytic agent work in the reaction is the direction we can research deeply in the days to come.
鋅和碘作用生成碘化鋅的反應,是用水作為催化劑,然而一小滴水卻使這個反應劇烈進 行,我們嘗試了多種和水具有相同作用的催化劑,由於反應時間極短不易測量,我們考慮由 產率部分著手,讓原本只需一小滴的水〈催化劑〉改為此反應的溶劑,計算其產率的變化。
實驗分為三部分,第一部份先是改變不同的溶劑,讓鋅和碘在不同溶劑〈水、酸化水、乙醇、酸化乙醇、甲醇、酸化甲醇〉下反應,計算出產率的變化,我們發現在酸中的產率的確較不加酸者來得高。第二部分我們改變加入鋅和碘的量,改變鋅和碘的比例,讓鋅由過量到成為此反應的限量試劑,觀察其產率的變化,我們發現碘作為限量試劑較鋅作為限量試劑的產率高。由於此反應在酸中產率較高,但酸的濃度高低是否又會影響產率呢?我們繼續第三部分的實驗,改變酸的濃度,讓此反應在不同的酸化水濃度的溶劑下反應,討論產率和酸濃度的關係,我們發現在一定範圍內〈0.01M~0.5M〉,酸的濃度越高,產率亦越高。
實驗方法是將鋅和碘置入同一試管中反應,並使其在不同溶劑中反應,接著離心,將碘化鋅水溶液與未反應完的反應物分離,將所得的碘化鋅水溶液使用結晶法得到碘化鋅晶體,秤重並計算其產率。
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大人都說要多吃菜、少吃肉,因為這樣會比較健康。 但是吃蔬菜真的一定比較安全健康嗎? 沒有農藥殘留的蔬菜有沒有其它的問題呢?除了農藥問題之外,看似平凡簡單的蔬菜其實有著大學問呢!
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「纖」入為「紙」-多種纖維質廢棄物之造紙效能與品質研究
本研究以多種纖維質廢棄物作為造紙原料,造出媲美市售的紙張。我們發現:玉米皮適合造紙且品質穩定;木屑、玉米梗造紙張力低且易碎;低濃度鹼液解纖的甘蔗渣膠質多,紙張透明易皺縮,但高濃度鹼液解纖,紙張平整白皙;柚子皮膠質太多,不易造紙;雜草可造紙但纖維明顯;竹筷纖維粗硬,紙張厚且張力低;稻草造紙品質佳且原料充足,是造紙界新星。改變變因上,果汁機打1分鐘可使張力提升;添加膠水或澱粉液能提升張力及降低吸水量;200目絹框抄紙張力較好;加熱浸泡50%雙氧水可漂白。校園落葉單子葉比雙子葉植物適合造紙。複合材料造紙時,添加少量甘蔗渣或柚子皮纖維可提升張力,少量竹筷纖維能使紙張硬挺。最後本研究推薦數種造紙方法供大眾參考。
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吸管也能吃?環保又健康的吸管-豆渣可食吸管的製作
一幕吸管插入海龜報導,促使政府全面限制塑膠吸管,也引發我們想製作終極環保吸管的動機。用小麥、豆渣、油、膠、糖製作吸管,小麥及豆渣為主成分,發現淺烘焙豆渣能支撐結構,膠和糖為黏著劑使纖維緊密,油使麵團有延展性,而蜂蠟為防水塗料,此最佳比例下可常溫下耐用5小時,符合使用基準。與市售吸管比較實用性、環保性及營養性。豆渣吸管和市售吸管相比,有易戳膜、大口徑(可吸珍珠)、耐酸性、耐溫性等優點。環保性測試發現1豆渣吸管為所有吸管中分解速度最快2且較石頭紙吸管其燃燒殘餘物相比不影響綠豆生長。豆渣吸管富維他命E,具抗氧化能力。而巧克力口味之豆渣吸管最受同學喜愛。因此我們做出了對環境友善、實用又健康的環保吸管。
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Poly(ADP-ribose)polymerase-1 對細胞內DNA damage修補的調控
Poly(ADP-ribose) polymerase-1 (PARP-1)是一個細胞核內的酵素,它可以被因DNA damage\r 而形成的DNA片段活化,並將NAD(+)上的ADP-ribose轉載到結合蛋白質。這些結合蛋白質對\r 於DNA的合成、DNA的修補、以及細胞週期的調控都有關係。因此,PARP-1被認為是維持基\r 因完整性的重要角色。根據初步的研究,抑制PARP-1的活性對許多疾病的治療都可能有效,\r 其中包括癌症、心臟病、中風、糖尿病、發炎以及反轉錄病毒的感染。然而,以藥物抑制一\r 個對DNA修補這麼重要的酵素會有什麼潛在的問題呢?為了要得到解答,我們需要進一步了\r 解PARP-1在DNA damage反應的機能。在這一份報告中,我製造了一個失去活性的PARP-1突變\r 種,即E988K。經過對E988K詳細的研究,我將比較及分析PARP-1野生型與E988K之間不一樣\r 的互動蛋白質,希望能對PARP-1所控制的DNA修補有更進一步的了解。\r \r \r Poly(ADP-ribose) polymerase-1 (PARP-1) is a nuclear enzyme activated by DNA strand breaks\r during DNA damage response and catalyzes the transfer of ADP-ribose units from the substrate NAD(+)\r to acceptor proteins. These acceptor proteins involve in modulation of chromatin structure, DNA\r synthesis, DNA repair, transcription, and cell cycle control. Thus, PARP-1 is believed to play an\r important role in maintaining genome integrity through modulation of protein-protein and protein-DNA\r interactions. PARP-1 has been the target for design of inhibitors for over twenty-five years. Inhibitors of\r the activity of PARP-1 have been claimed to have applications in the treatment of many disease states,\r including cancer, cardiac infarct, stroke, diabetes, inflammation and retroviral infection. However, are\r there potential problems associated with inhibition of this DNA-repair enzyme? To answer this question,\r we need to further understand the biological function of PARP-1 during DNA damage response. In this\r report, an enzyme dead mutant (E988K) of PARP-1 was generated. Detailed studies of E988K show that\r E988K could be used in the following studies. Compare and identify the different associated proteins of\r PARP-1 wild-type and E988K will shed light into the molecular mechanism of PARP-1-mediated DNA\r repair.
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非線性振動-單擺運動方程之數值分析與研究
在我們的這主題中,以單擺為主要研究對象,利用數值方法寫成計算程式,並藉 以整理運用繪圖軟圖,描繪其運動的模式之物理意義,便是我們此主題的重點所在, 並且我們更深入於實際物理情況中,消耗力或摩擦力終將阻滯運動以迄振動不再發 生。我們一開始利用RK4 數值方法將單擺運動方程寫成Visual Basic 6.0 計算程式來解 其運動方程得到等時距之角度及角速度,再藉由Matlab5.3 繪出我們想要的圖形―角度 與時間,角速度與時間以及角速度和角度之相圖。所得的圖形中,也分為有或無阻尼, 每項中又有不同的討論,如:在已知的任何一個初始狀態下,其擺動的情況當然也有 互相之對照比較,最終得出精采的結果:且將單擺作了完整且一般性的分析。因為此 番分析研究是屬理論性,雖然實驗之佐證但我們藉由Easy Java Simulation(台灣師範大 學黃福坤教授在http://140.126.110.168/~phy50/所提供免費下載)製作動畫來驗證了我們 所得的結果是十分正確無誤【它只能得到各初始條件下之單一圖形,而我們的方法可 以將各單一相圖統整成相平面及相空間並分類】
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無尾翼飛行器(Tailless Aircraft)在軍事上的價值極大,且對於目前正在起步的微飛行載具(Micro Air Vehicle)而言,亦是值得嘗試與投資的。然而,由於無尾翼飛行器缺乏用以平衡的水平尾翼,造成其靜態的不穩定,即使設法提高靜態穩定特性,但其氣動力阻尼低、穩定性仍舊不佳。操縱上更是困難,在飛行穩定性與控制系統設計上極其挑戰性。本研究目的在探討無尾翼飛行器之穩定性與控制技術,改善其先天之不穩定特性,考慮之項目有縱向靜態穩定性、動態穩定性、控制面與組件配置等因素等進行詳細之探討。首先,找出了適用於無尾翼飛行器之Reflex翼形,接著建立無尾翼飛行器之非線性縱向動態模式,然後針對一翼展8Ocm之小型飛行器進行外型設計,並觀察分析其實際飛行狀態,再以理論與經驗公式估算無尾翼飛行器之氣動力導數,探討其飛行穩定與操控性能。此外,並運用古典控制PID控制法則,設計控制器進行非線性受控系統之動態響應模擬。由模擬結果可看出,經由翼剖面改變與控制系統的輔助下,大幅提高了其性能,使得無尾翼飛行器克服了先天的不穩定特性,更提高了其發展空間 The tailless aircraft has a great value on the military use. Meanwhile, it is worthwhile to try and to invest in it for the investigation of MAV(Micro Air Vehicle), which is being developed now. However, because of lacking horizontal tail which is used for balance, the tailless aircraft is static unstable. Even with the attempt to enhance its characteristics of static stability, the stability of the tailless aircraft is still poor for the sake of it's low damping in aerodynamics. Therefore, it is a challenge to flight stability and control system designing. The purposes of this research are to study the stability and the control technique of the tailless aircraft. To improve its congenital lacking of stability, thought over the longitudinal static stability, dynamic stability and control system. First, find the "Reflex" airfoil is suitable for the tailless aircraft. Second, set up a non-linear and longitudinal dynamic model of the tailless aircraft. Third, design an 80cm span small airplane. Hence, observe and analyze its flying condition. Finally, utilize the theoretical and experiential equations to estimate the aerodynamic derivatives and investigate its stability and controllability. Besides, use the PID controller to proceeded the time-response simulation of the non-linear system. The result of simulation shows that the performance is improved through the change of the airfoil and with the auxiliary of the control system. With this improvement, the tailless aircraft overcome the congenital lacking of stability to broaden its utilization potential.
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用雙手合攏當樂器,掌心空間當共鳴箱,用嘴吹氣在兩大拇指之間的空隙,吹出的聲音像笛音一般,這就是「手笛」。能吹出笛音跟嘴形無關,要成功的吹出笛音而不是氣音,須符合3個條件:1.吹孔空隙要小(<0.15公分);2.吹孔空隙兩旁要有彈性物質(兩大拇指的肉);3.要順著掌心空間切線位置吹氣。而我們也發現:1.掌指關節間愈寬,笛音愈低;2.掌心空間直圓周長愈長,笛音愈低;3.愈用力吹手笛,笛音愈高;4.吹孔寬不影響音高;5.掌根開洞愈大,笛音愈高;6.掌心空間愈大,開洞要更大才有明顯的音高變化;7.手指開洞會比掌根開洞影響手笛音高來的明顯;8.手笛開洞的位置會影響它的音高,距離氣流其始位置較近,影響音高較明顯。
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