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一等獎

毛細管內液體流速之探討及黏度測量方法之創新

有一次上實驗課時看到鄰桌的同學正以實驗室的毛細管吸吮一瓶\r 葡萄汁,每當他吞嚥時,毛細管內殘餘的葡萄汁竟然以近似等速的狀\r 態降回果汁瓶裡,這似乎違背了重力加速度的常理,是毛細管的影響\r 嗎?還是葡萄汁特有的現象?這與毛細管插入葡萄汁的深度有關嗎?\r 這一連串的問題皆因升學壓力而無暇深究。\r 升上高中的那年暑假,我參加了學校舉辦的資優科學營,在物理\r 實驗課中恰好遇到了以毛細管測量液體黏度的實驗,使我有機會深入\r 思索毛細管內液體流速的問題。這個實驗很不好做,要調整兩個定高\r 容器,使水平毛細管兩端產生固定的壓差,讓流經管內的液體為等速\r 的流動。大家手忙腳亂地操作了近三小時,測出來的黏度不僅和老師\r 公布的答案差距甚大,而且各組同學所測得之結果也大相逕庭,不過\r 我們都體驗到了液體黏度對流速的影響。\r 實驗的誤差為什麼那麼大?扣除人為操作誤差後儀器本身還有多\r 大改進空間?有否更精簡的方法測量黏度?毛細管中液體的流速真\r 是固定的嗎?把毛細管斜置或是垂直架置,流速還會固定嗎?重力不\r 會影響流速嗎?若流速真為固定的,如何控制或改變流速呢?是否可\r 以利用流速來測出液體黏度?\r 由於我對這個實驗的專注,在學校選修的專題課程中即以此為題\r 目做長期的研究,在老師的指導下,我和同組同學不停地查閱有關書\r 籍及整理資料,漸漸研究清楚原理後定出實驗計畫,並開始購買材料\r 與工具,長期地動手實驗及改進,兩年來我們利用毛細管中液體的等\r 速及不等速流動的特性,發展出了兩種既精簡又準確的液體黏度測量\r 法,以下就是整個研究及創作的過程。\r \r \r The viscosity is one of the most important parameters of the fluids. In conventional viscosity experiments, capillary-based viscometers are widely adopted because of their user-ready devices and moderate prices. However, to accurately measure the viscosity, the fluid velocity must be kept constant; otherwise, the fluctuation may cause the serious deviation. Besides, traditional capillary viscometers often require a long time to make the measurement. This research aims at exploring the capillary fluid mechanics and developing accurate and rapid methods to measure the viscosity. In this study, we developed two creative viscosity-measuring methods, the gravity sloping helical structure and the gradational liquid-level difference, and constructed two cost-effective capillary viscometer prototypes accordingly. The gravity sloping helical structure employs a long helical capillary as the flow channel and utilizes the gravity force to keep the fluid velocity extremely constant. The highlight of this method is that we can see the fluid flow through the capillary directly. On the other hand, the gradational liquid-level difference method uses the pressure sensors to precisely monitor the liquid-level difference, which drives the flow in the capillary, and allows automatic measurement of viscosity. Compared with computer simulation, the experimental results agreed well with the theoretical values. The gravity sloping helical and gradational liquid-level difference methods achieve 0.5% and 0.8% accuracy respectively. In addition, the automation of viscosity sensing also greatly facilitates the viscosity measurement. Furthermore, these two methods are both valuable for incorporating into educational purpose and industrial application.

乒乓球彈跳運動研究

為了測量測量乒乓球彈跳,設計了測量的方法,基本構想是將乒乓球在木板上的彈跳(接觸與離開)視為開關的ON與OFF,將訊號產生器所產生的電訊號接到乒乓球上,木板接到電腦錄音輸入端,當乒乓球與木板接觸時,形成通路訊號進入電腦,由錄音程式加以記錄,反之為斷路,記錄停止。但如何將乒乓球、木板由不能導電的絕緣體轉換成可以導電的導體,而又不能影響乒乓球原本彈跳性質?想出了用2B鉛筆(含石墨)將乒乓球、木板塗黑轉變為導體的方法,解決這個問題後,成功測量出以下乒乓球彈跳時各項的記錄:1.彈跳次數2.碰撞作用力3.接觸時間4.飛行時間。最後以力感測器直接測量碰撞作用力,來驗正此實驗正確性。

Complicated reproductive system in the Brown-foot Ant, Technomyrmex brunneus. (Hymenoptera: Formicidae)

本研究主要針對棕色扁琉璃蟻的生殖型蟻以及其生殖行為進行探討。在生殖季節中,處女蟻后出現的比例明顯高於有翅型雄蟻。而蟻后的死亡率高,且其所產下的卵有27%為畸型卵,具有生殖衰退(reproductive decline)的現象。此外,部分棕色扁琉璃蟻聚落中,蟻后會被工蟻逐出巢外並進行搬運屍體、搬運廢棄物及覓食等職蟻的行為。 有別於大多數的蟻種,棕色扁琉璃蟻存在著工蟻型雄蟻(Ergatoid male)和具有生殖能力的工蟻。工蟻型雄蟻的外型與氣味皆與一般工蟻相似,羽化後即具有生殖能力,可與聚落中多隻生殖型工蟻行多次交配(multiple mating);而可生殖的工蟻又包含三種中間階級(intercaste),於體長、複眼數目、胸線皆有所差異,微卵管數目則可依階級分為4至6條、12至14條、18至22條三種範圍。 棕色扁琉璃蟻的繁衍方式是多樣且複雜的:聚落中主要由生殖型工蟻進行有性生殖及孤雌產雌,繁殖出蟻后、工蟻和二種型態的雄蟻。而蟻后則可與有翅型雄蟻交配,但只產出一般工蟻及生殖型工蟻。 本研究首次提出了棕色扁琉璃蟻具有工蟻型雄蟻,而對這種具有複雜生殖方式的社會結構之探討,也為聚落發展的方式提供了一個新的研究方向

停車就是彈硬幣

在這個科展中我們要研究兩個非常有趣的問題:\r 停車場問題 與 彈硬幣遊戲.\r 停車場問題是這樣的:在一條單行道上有n個車位,編號從1到n。現在有n個司機排成一排要進入停車。但是每個司機都有怪癖,各自有最想要停的位子。他們依序將車子開進單行道,如果想要停的位子是空的,當然停在這個位子。但是如果不巧那個位子已經被停了,不得已只好找下一個空位,姑且停之。但是如果往下找都沒有空位,由於是單行道,司機就只好開走不停了。\r 比如說,如果現在有五輛車,司機的喜好分別是(3,1,2,5,2)。則五輛車都可以順利停車。但是司機的喜好如果是(3,1,4,5,4),有些車就無法停車了。\r 彈硬幣遊戲是這樣的:考慮圓內接正n+1邊形,任意兩點都連線。這正n+1邊形中有一個頂點P是特殊的,每個頂點上一開始都放有一些硬幣(各點硬幣數可以不同)。如果P以外的某個頂點上的硬幣數n個,我們可以對這個頂點進行操作:一次操作是指將這個頂點上的硬幣各分一個給每個其他頂點。點P只在其他點都無法操作時操作。我們不理會頂點P上的錢數,因此這個遊戲可以無限地玩下去。

SPYNIK

Nikhil’s technology studies main client told him how she had no idea about how to\r stop her children looking at all sorts of website and asked him for a solution to a\r problem he initially thought was impossible to crack. Nikhil has definitely ‘cracked’\r this one: with a dedicated website his clients can log into and monitor what is going on in any computer the little box of electronic tricks is plugged into from anywhere in the\r world. This unit controls the electronics and stores the history of the web pages that the user has visited. Not only that, the client can cut the internet (and re-connect it) to the remote computer at will. At the heart of Nikhil’s box of tricks is a web-server module (The Wiznet) and a powerful microcontroller, the AtMega32. Nikhil has designed the\r board, connected the electronics and written the code to allow it to communicate with\r the computer and remote client.

USING IRON-STEEL INDUSTRIAL WASTE SLAGS AS A FERTILIZER

Steel slag, is received from iron and steel production facilities in Turkey, and is up to 25-30% from steel production. These couldn’t have been reclamation for any field of use and free stored in nature. When the structure of this slag examined, it was contained metallic formation (Fe2O3, Al2O3, MnO2, MgO2 etc.) and oxide compositions (SiO2, CaO2 etc.). The aim of this project is investigate metallic content of steel slag used as fertilizer in plants. For this purpose, slag is used to determine the physical and chemical characterization. Then, it is separated from metallic content by using shaking table and multi gravity separative (MGS) method. After these procedures, there are determinate 6 groups with different densities and different grit size. Element analysis was made of these groups by atomic absorption spectrophotometer (AAS) and ICP-OES system. In addition, mineral analysis was determined by XRD device. Thus, within each group minerals have been identified. Slag-soil mixture was prepared for determination the highest yield of using six different slag groups as fertilizer in the plant. Thus, corn crops were grown in different combinations. Then harvested corn plants and done soil analysis of the plants. As a result of experiments, percentage of the most effective slag-soil composition for corn was determined. The highest yield in the slag pot was determined the rate of %12.5 and coarse-grained. Ideally, the slag content found to be chinerals such as merwinite (3CaO-MgO-2SiO2), akermanite (2CaO-MgO-2SiO2), gehlenite (2CaO-Al2O3-SiO2). Thus, it was detected the steel slags can be used as feed material for plants. Hence by maintaining the ecological balance economic contribution to the country was achieved.

二維顆粒流體崩塌倒序現象之探討

本研究探討斜面上二維顆粒體流動的現象,分析各種變因(軌道盒傾斜角度、軌道盒側壁傾斜角度、軌道盒出口大小、顆粒粒徑)對斜面顆粒流性質的影響: 一、 顆粒流圖形與表層崩塌角 (一)顆粒流圖形: 「V字下滑」 (二)表層崩塌角: ‧正向關係: 軌道盒傾斜角 ‧負向關係: 軌道盒側壁傾斜角、粒徑 ‧ 未知關係: 出口大小 二、 中央線上目標顆粒的落下時間 ‧正向關係: 軌道盒側壁傾斜角度 ‧ 負向關係: 軌道盒傾斜角度、出口大小 ‧未知關係: 粒徑 三、 探討傾斜軌道盒顆粒流中,崩塌以及倒序區域分布圖形 ‧起始位置較高且較遠離中軸線的顆粒將可能發生「起始位置較高的顆粒卻較早落下」的倒序現象; 依照顆粒實際發生的崩塌類型,能將軌道盒分為穩定區、內崩塌區及表層崩塌區。 ‧崩塌區域的分佈受顆粒粒徑與軌道盒側壁傾斜角影響。

Reactions of Bis(oxy)enamines with Transition Metal Halides

Synthesis of halooximes has attracted much attention given their importance as precursors to proline derivatives1, unnatural amino acids2 and a host of alkaloids3. Halooximes have numerous industrial and biological applications 4, for example oxime ethers increases specific channel opening activities, acting as potential targets in drug treatment for various diseases 5, most adrenergic β-receptor blocking compounds also conform to the structure of oxime ethers 6. They also have vitro antifungal activities against certain plants7. A known method for the synthesis of 3 using Me3SiX as a Lewis acid, via intermediate enamines with acyclic/ cyclic bis(oxy)enamines, gives yields between 21-68%. Low yield stems from lack of reaction specificity2. In this work, we investigate coupling nitrogen-oxides with CoBr2 to synthesise halooximes in high yield. Initial cyclic/ acyclic bis(oxy)enamines were prepared by reacting 1 equiv. nitro compound with 2.4 equiv. in excess of dichloromethane under argon atmosphere at a temperature of 0ºC. 2.2 equiv. of TMS-Br was further added and left to stir till thermal equilibrium with room conditions. The cyclic/ acyclic bis(oxy)enamine was isolated upon aqueous work-up, filtration and evaporation. Synthesis of halooximes was carried out by reacting 8mL to 1mmol equiv. of THF and 2 equiv. of CoBr2 under argon atmosphere and left to stir till CoBr2 dissolves. 2mL to 1mmol equiv. of CH2Cl2 was added to 1 equiv. of bis(oxy)enamines. The reaction mixture was left to stir at room temperature for 2 hours, after which aqueous work-up, filtration and evaporation were carried out. Our results are summarized in Table 1. We also obtained relatively high percentage yields for the direct synthesis of bromooximes from cyclic nitronates via a one-pot procedure: Low yield stems from lack of reaction specificity2. In this work, we investigate coupling nitrogen-oxides with CoBr2 to synthesise halooximes in high yield. Initial cyclic/ acyclic bis(oxy)enamines were prepared by reacting 1 equiv. nitro compound with 2.4 equiv. in excess of dichloromethane under argon atmosphere at a temperature of 0ºC. 2.2 equiv. of TMS-Br was further added and left to stir till thermal equilibrium with room conditions. The cyclic/ acyclic bis(oxy)enamine was isolated upon aqueous work-up, filtration and evaporation. Synthesis of halooximes was carried out by reacting 8mL to 1mmol equiv. of THF and 2 equiv. of CoBr2 under argon atmosphere and left to stir till CoBr2 dissolves. 2mL to 1mmol equiv. of CH2Cl2 was added to 1 equiv. of bis(oxy)enamines. The reaction mixture was left to stir at room temperature for 2 hours, after which aqueous work-up, filtration and evaporation were carried out. Our results are summarized in Table 1. We also obtained relatively high percentage yields for the direct synthesis of bromooximes from cyclic nitronates via a one-pot procedure:

以彈性體模型評估心血管疾病之新方法初探

我們根據物理學的彈性體振動模型發現:主動脈硬化程度可由測量主動脈相對於心臟運動的延遲時間分析得知。我們除了由樣品之超音波影像分析驗證此一觀念之外,還用一自製模型進行實驗,模擬血管厚度對延遲時間的影響,實驗結果與理論相吻合,證實了彈性體模型之可靠性。在診斷方面,此方法可用目前臨床使用的心臟超音波儀直接進行測量,使得它具有方便、普遍的優點;而且可由體外的胸前超音波掃描(TTE)進行觀測,具有非侵入性、免除受測者的不適及避免副作用,此外,能定量分析、早期診斷、鑑別度高也是此方法重要的優點。According to the elastic oscillation model of physics, we found that the aorta stiffness could be obtained by measuring the delay time of the aorta relative to the cardiac motion. The idea was confirmed by an analysis of the echocardiograph images of several samples. A home-made mechanical model was also employed to simulate the effect of cardiovascular thickness. The experimental results fitted the theory very well, verifying the feasibility of the elastic oscillation model. This measurement could be carried out with the conventional echocardiography instruments, making it convenient and common. Furthermore, the delay time could be measured with TaransThoracic Echo (TTE) instead of TransEsophadeal Echo (TEE). This non-invasion can avoid patients’ discomfort and side effect during medical process. The quantitative measurement also enables that the diagnostics can be progressed in advance.

黑暗中的光芒-林下植物葉綠體囊膜電池

林下(陰地)植物長期生活在較少陽光的地方,卻依然欣欣向榮。因此,我們針對林下植物的葉綠體囊膜電池做討論,希望可以找出發電效率更高的葉綠體囊膜電池。