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從n維平行體到線形映射的脹縮率

線段可以作為度量線上一切長度之基礎。平行四邊形可以作為度量平面上一切面積之基礎。平行六面體可以作為度量三度空間中一切體積之基礎。

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追蹤消失的白糖

我平常喜歡吃甜的東西,喝杯開水,也總要放一點白糖,有一天我發現放進去五湯匙多的白糖,不知道消失到那兒去了,照理在液體中沈下多少體積的東西,應該會增加多少體積才對。怎麼我放進那麼多的白糖,怎會消失得無影無踪呢?我覺得很奇怪?於是我開始追踪放進水裹的白糖。

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飛盤與氣體浮力的關係研究

最近學校很流行玩飛盤,飛盤是一種很有趣的玩具,他長得很奇怪,像一個裝菜的盤子翻過來一樣,可是我覺得很奇怪,它為什麼會飛呢?它為什麼能在空中繼前進而不會很快的掉落呢?這個問題迷惑著我,也使我對它產生了好奇心,於是在老師的指導和同學的幫助下展開了連串的研究工作。

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Synthesis and Characterization of Niobium Nitride Nanowires

This project aims to explore the potential of inexpensive in-situ deposition of niobium nitride nanowires to improve electrical conductivity. Transition metal nitrides are well known for attributes such as superconductivity, high melting point, simple structure as well as excellent electrical and thermal conductivities. In particular, niobium nitride possesses exceptional hardness and high reflectivity, as well as being a stable field emitter, making it well suited to applications as a cold cathode material. Niobium nitrides are formed by the uptake of nitrogen by niobium. This is achieved by the exothermic formation of an interstitial solid solution of nitrogen atoms in the bcc lattice of the niobium. Existing research has established the possibility of preparing niobium nitride by heating niobium in nitrogen or ammonia over a range of temperatures, by heating niobium pentaoxide and carbon in the presence of nitrogen as well as by chemical vapor deposition of other niobium compounds, nitrogen or hydrogen. For the purpose of this study, a two-step process was used for synthesis. The benefits of a two-step process over direct ammonolysis are apparent, from the greater degree of freedom pertaining to parameter determination. Additionally, characterization of niobium pentaoxide nanowires synthesize under similar conditions is also made possible by terminating the reaction earlier. NbN nanowires were synthesized by annealing niobium pentaoxide nanowires at 850 oC for 2 hours. Subsequent characterization was done using Raman Spectroscopy, X-ray Diffraction (XRD) and Scanning Electron Microscopy (SEM). The presence of NbN nanowires via the conversion of Nb2O5 was ascertained by the absence of sharp peaks at 1000 cm-1 for Raman Spectroscopy and XRD plots. Field emission (FE) properties and electrical properties of NbN nanowires were then measured. NbN nanowires were found to have a high turn-on voltage, stable and relatively good field emission characteristics, demonstrating its potential as a cold cathode material. No current saturation was observed for an applied electric field of 0 to 6.0 V/ μm (5). This suggests a low degree of contact resistance for nanowires produced by this method of annealing, since the passage of electrons is not obstructed. Hence there will only be a small voltage drop between the SiO2 substrate and NbN nanowires. Samples containing NbN nanowires were dislodged by ultrasound to form an aqueous suspension of nanowires. A drop of suspension was dripped onto gold-finger substrates, and current-voltage (I-V) measurements of resultant nanowire bridges were taken. NbN nanowire bridges display Ohmic properties, in comparison with Nb2O5 nanowires that are semiconducting. Nanowire bridges obtained by heat-drying were denser and had better electrical properties than those obtained by evaporation to dryness. NbN nanowire bridges display Ohmic properties, in comparison with Nb2O5 nanowires that are semiconducting. Further work would include varying the cooling processes to observe any changes or deformation. Additionally, niobium nitride nanowires can be hybridized with carbon nanotubes (CNTs). A more in-depth comparison between niobium oxide and niobium nitride nanowires is also proposed, along with exploration of the nitrification of other transition metals.

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史特林你真酷

本研究是以致冷晶片來降低史特林引擎冷卻部溫度提昇運轉效率,並使用發電晶片來提供致冷晶片致冷時之所需電力,希望能藉由此實驗探討,創造效能更佳的史特林引擎,降低對石油的依賴性。

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閱卷電腦的完成,續閱卷電腦的設計

自六十二年起大學聯考招生除作文外均採用電腦閱卷,因此閱卷電腦和我們有了密切的關係,並且引發了我們研究的動機。今各校亦仿大學聯考之方式舉行模擬考,並且請老師閱卷,我們為了減輕老師的負擔,乃設計了這套電幽,並儘量降低成本!以期推廣至各校普遍應用。上次我們的硬體(內部構造)設計,曾參加全國展覽,擭得各位師長的鼓勵以後,乃繼憤潛心研究,於課外時間製造完成本電腦,並完成初步的動作。為了消弭大眾對於電腦高深莫測的恐懼心,乃以淺顯的文字介紹電腦的內部構造,希望能幫助大家認識電腦,了解電腦並引起大家對電腦研究的好奇心,以破除電腦神祕的外衣。

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腳為什麼會陷到沙裡去?

有一天媽媽帶我和妹妹去海邊玩,媽媽穿的高跟鞋陷得很深,妹妹和我的就沒陷得那麼深,為什麼?妹妹和我開始研究。

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Safety in the building

The purpose: is to protect the building against the fires\r The main idea: is an Automatic emergency exit.\r When fires happen, the smoking detector works, giving sound and light.(signals)\r Then the emergency Exist opens automatically.

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線上教學資源

自製橫波演示器及教學上的使用

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翻開東北角那一頁---和美一帶漸新統貝類化石排列方式和古水流關係之探討

This study tries to reveal how the velocity of flow influents the orientations and scattering patterns of the two-valve shells (we use Pecten in this study) during depositing processes by comparing the laboratory studies with the field observations. We learn from the laboratory experiments that the shells deposit at random directions when they are too crowded and are oriented to a certain direction when they are more scattered. We also find out that the shell fossils whose dorsal sides towards downstream with upward concaves are most likely to move. On the contrary, the shells whose dorsal sides towards upstream with downward concave are the most reluctant to move Examinations of the outcrop of the bedding of Pecten fossils, which are located near Long Dong, the northeastern tip of Taiwan, show that a lot of the shells settled along a certain direction and most of their concaves are upward. However, some of the shells with obvious orientation have downward concaves, which implies the depositional environments were under high current velocity. And the numbers of the shells whose dorsal sides are oriented to Northern East are about equal to those whose dorsal sides are oriented to Southern West. This result coincides with the results of the laboratory study. However, the experimental results can apply to the field analysis under certain assumptions.本研究就影響貝殼排列的水速作試驗,尋找水流和貝殼排列的關係,並和地層中實際的貝類化石做比較,藉以回推古老沉積環境。結果發現大量貝殼集中的情況下,貝殼間彼此的影響力會大於單純的水流沖擊;當貝殼較分散時,可以看出貝殼的頭部皆會一致朝向水流的來向作排列。而最適合移動的型態是凹口向上且頭部不朝水流來向的貝殼,而最穩定的型態是頭部朝水流來向的凹口向下貝殼。觀察實際地層,貝類化石大致上也有方向性的排列且正反面貝殼都有,可以推得當時沉積的水流大,故有足夠的動能讓貝殼重新排列。但由於試驗環境定和自然環境有所差異,仍有限制存在。

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種子萌芽及種子萌芽的研究

從小對於種豆萌芽的現象就有很大的興趣,直到現在六年級還是不減當年,只要有人提出有關種子的問題,我們都渴望能進一步實驗,以尋找出答案。尤其日常見到農人收割稻子,並挑選品質優良的種子流到明春播種,這些引起我們的好奇,想暸解影響種子萌芽的因素及能否控制這些因素而牽制種子的萌芽呢?因此我們就在老師的指導之下,進行各種實驗的研究。

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線上教學資源

森棚教官的數學題-用三湊三

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