一滴溶液的顯微電解世界
Whe we think of chemistry experiments in schools from the view of environmental\r protection, microscopic chemistry experiment with reduced quantity and waste is\r the trend for experiments in the future. It is also the target that everybody shall\r aim for. After many failures and instructions from teachers, I finally successfully\r performed electrolysis of the most micro-volume of one-drop solution. It was also\r unbelievable to perform quantitative test within the electrolysis time of color\r disappear from the blue cupic sulfate solution.
\r To clearly see the one-drop solution electrolysis, instrument starts from magnifier\r to self-assembled micro project, then upgraded to the miro-visual screen. It not\r only can record,also plays/shows in the computer. Most importantly, it is the most\r environmental protection effective and also zero pollution microsopic chemistry\r experiment. It is obviously a target of future development trend.
\r 我們從環境保護的角度去思考常校的化學實驗時，減量減廢的微型化學實驗已是未來實驗的趨勢，也是大家應共同努力的目標。在多次失敗及老師的啟發下，我終於成功的做到電解最微量的一滴溶液。對於從藍色硫酸銅溶液顏色消失的電解時間裡，還可做定量的檢定感到不可思議！
\r 為了更清楚看到一滴溶液的電解情形，儀器的設計由放大鏡到自組顯微投影機，最後進階到顯微視訊的畫面，它不但可記錄下來，而且可在電腦中播放。最重要的是：最環保也最接近零污染的顯微化學實驗，已然是未來可發展下去的目標。
生活中的碳-探討自製的活性碳之吸附雜質及竹炭屏蔽電磁波效應
有鑑於SARS 期間活性碳口罩因原料均從國外進口，而造成活性碳急需用時的短缺，於是我們的研究是以國內最常見的木材自製成活性碳，並探討活性碳對生活週遭常見物質的吸附能力。我們利用六種不同的木材配合兩種活性化方法來製成不同的十二種活性碳，觀察活性碳對有色溶液的吸附效果，發現不同的活性碳對不同的物質有不同的吸附效果。在定量實驗中，我們採用不同大小、不同性質的物質依次為氯離子、氨分子、葡萄糖分子及三氧化二砷等，用十二種不同的活性碳作吸附效果的比較，發現每種物質都有對其具有最佳吸附能力的活性碳。再利用電子顯微鏡觀察並測出活性碳孔洞的大小，將結果與活性碳對各種物質的吸附能力相對應而得知，【1】活性碳的孔洞大小與物質質點相容性大即得最好的吸附效果【2】雖然木材本身並不帶電，但其中所含的礦物質可能會具有電性，所以在必要情況下亦可將電性列入考慮。同時，在現代化的生活環境中，人們與電磁波的接觸已無可避免；而電磁波因頻率的差異而有不同的特性，因此對於人們的影響也不相同，新聞報導中常出現宣稱竹炭具有遮蔽電磁波的效果。於是我們深入地去探討竹炭對電磁波的影響原因。 在我們實際測量過程中發現，基地台、高壓電塔、行動電話和家庭電器所釋放之電磁波總和均在安全範圍之內。竹炭的燒製溫度須達550℃以上才可在內部形成具有導電性的石墨結構才進一步具有屏蔽效果。 ;During the ravage of SARS, a great amount of activated carbon was imported to Taiwan, leading to the shortage of actived carbon for emergent use in our country. In view of this phenomenon, we investigated six kinds of wood that are most commonon the market and processed them into twleve kinds of actived carbon. We found that different actived carbon has distinct adsorptive power on different substances by observing theadsorption in the colored solutions. In quantitative experiments, we applied substances of different sizes and properties (chlorine ions, ammonium ions, glucose molecules, arsenic(Ⅲ) oxide) to compare the adsorption of these twelve kinds of actived carbon. We found that each substance is adsorbed the most by a certain kind of actived carbon. Then we observed the apertures of actived carbon under stereoelectric microscope and contrast the result with adsorption. We had two following findings: Actived carbon has better adsorption if its apertures fit the adsorbate molecule well in size. Wood itself doesn’t have electric charge. But sometimes the minerals contained would enable it to have electric charge. We have to take the electric charge into consideration in the experiment if necessary. At the same time, in a modern life, the contact between us and electronic waves are not avoidable. Electronic waves with different frequency have varied characteristic and therefore cause dissimilar influences on humans. The news reports keep on showing the charcoal can shield us from electronic waves. Therefore, we want to find the causes why the charcoal affects the electronic waves. During the process of the research, we find that the total of all electronic waves released by electricity tower, mobile phones, household electronics are within the secure spec. The charcoal has to be burned higher than 550℃ and then it can generate the electric conduction graphite structure inside and then it can have the shielding function.
平面切立方體內單位立方格數極值之計算
我們先假設有一正方體及一截過正方體之平面，並設正立方體為一k*k*k 之立體。為計算平面截過之單位正立方體個數，我們必須先分別計算各層被切過之個數再將之相加，因此將各層面投影至同一平面，簡化為平面上之問題，並討論其性質／規律，計算平面截此正立方體之個數。如此，便可以一般化數學式計算平面截正立方體個數之問題。接著，用以上方法為基礎，討論各種平面切正立方體之類型，將被平面所截之單位立方體個數以電腦程式算出，觀察數字變化及其性質規則，並找出最大值發生之條件。 We initially supposed that there are a regular hexahedron consists of unitary n × n cubes and a plane which incises the regular hexahedron. To calculate the total number of the unitary cubes incised by the plane, we can first calculate them layer by layer and then sum them up. And further, we project each layer on the same plane, so the three-dimensional problem is simplified into two-dimension. By making use of the character which results from projection, we can easily calculate the number of the unitary cubes incised. Consequently, we are able to calculate them with a general equation. Afterward, we research each circumstance that the plane incises the regular hexahedron on the base of the mentioned methods. Calculate them with self-designed computer programs, and observe the regulation and change of the result. Furthermore, we can find out when it will achieve the maximum.
澱粉?抑制劑之研究
植物合成澱粉?抑制劑可以對抗動物的取食，國外實驗證明數種澱粉?抑制劑對害蟲防 治具有顯著效果，其中以腰豆(Phaseolus vulgaris)研究最多。我們利用5% T.C.A.進行粗萃，從台灣常見豆類中篩選出四季豆(與腰豆同種不同品系)與菜豆，對麗蠅的澱粉?具有明顯的抑制效果，對豬胰臟與黃豆澱粉?的抑制效果則小或無，此種抑制特異性深具害蟲防治的潛力。經由溫度與pH 的試驗發現粗萃中的澱粉?抑制劑成分應為蛋白質。我們以四季豆作為繼續研究的對象，將粗萃進一步純化，經由陰離子交換與膠體過濾層析，分離出單一蛋白質，經蛋 白質定序比對確認其可能為國外發表的腰豆澱粉?抑制劑—αAI-1。經由測試發現此抑制劑在 85℃時仍能抑制果蠅澱粉?，為一相當穩定的蛋白質；且抑制劑的作用受pH 值影響很大，在偏酸性環境下的效果最好，與昆蟲分泌澱粉?的部位亦為酸性環境有相當密切的關聯；且其 抑制作用具特異性，可明顯抑制果蠅、入侵紅火蟻、白蟻、蟑螂及麵包蟲等昆蟲的澱粉?活性，對人類唾液、豬胰臟、四季豆本身及黃豆澱粉?的抑制效果很小或無，值得繼續深入研究。 Plant amylase inhibitors can fight against predation from plant-eating animals. It has been reported that several amylase inhibitors have an obvious effect on pest control; among them that from Phaseolus vulgaris got the most surveyed. 5% T.C.A was employed to make crude extracts. We have screened the amylase inhibitor activities from crude extract among beans common in Taiwan. The inhibitors from both string beans (the different strain of Phaseolus vulgaris) and cowpea notably inhibited the amylases in Chrysomia megacephala, but little or no inhibition in porcine pancreas and soy bean. This specific inhibition behavior suggested strong potential in pest control. Its activity can be affected by temperature and pH suggested that amylase inhibitors in crude extracts should be proteins. String beans were chosen to be further purified from the crude extracts. A single protein was isolated after ion exchange and gel filtration chromatography. Through protein sequencing, the partial amino acid sequences were highly homologous to that ofαAI-1 from Phaseolus vulgaris, indicating it might beαAI-1. The purified protein still can inhibit the amylase from Drosophila melanogaster at 85℃, suggesting it is thermal-stable. Its activity was affected by pH and reached the peak in weak acidic environment, which might be related to the fact that amylases are secreted in acidic environment of insect’s midgut. It obviously inhibited the amylases from D. melanogaster,Solenopsis invicta, Odontotermes formosanus, Periplaneta Americana Linnaeus, and Alphitobius sp., while not to human saliva, porcine pancreas, soy bean and string beans itself. The unique pattern of inhibition activities of the purified amylase inhibitor was worthy of further anlysis.
這裡真安靜-隔音材質的探討
本實驗針對隔音材質的特性，如各孔板之孔徑、開孔率，並以夾層做不同孔板配置進行研究。本主題共進行三階段的實驗。第一階段探討不同材質的影響，因材質加工問題，實驗誤差過大；第二階段改以PP 塑膠板探討，因儀器誤差，數據難以解析；第三階段仍以PP 塑膠板探討，並修正實驗步驟，以降低實驗誤差。本報告乃以第三階段實驗結果做探討。為了提高實驗準確度，將整個實驗分成若干組，在實驗前後以空白測試，以減低實驗誤差。利用Excel 軟體，進行各組實驗數據噪音傳送損失之修正與分析。本試驗以125Hz、250Hz、500Hz、1000Hz、2000Hz 及4000Hz 六段週波頻率做測試。由分析結果顯示，孔徑與開孔率、同心圓的排列方式，對噪音傳送損失有顯著的影響。;This experiment is to focus on the properties of sound barriers, such as hole diameter, open areas, and the layout of holing boards. We have performed experiments in three steps. In the first step, we discussed the differences between different kinds of material but found many errors caused from faults in the process of making boards. So in the second step, we chose the ploy-propene board but still found errors from instruments. And in the final step, we used the ploy-propene board again and modified the experiment procedure to lower the error from instruments. The report is based on the final step data. With a view to raise the precision of the experiment, we divided the experiment into several parts with the blank test. We modified and transferred the original data to the noisy transfer loss (TL) in the same intensity level, and analyzed the data with Microsoft Excel. In experiment, we detected the noise-pollution level (dB) in the frequency of 125Hz, 250Hz, 500Hz, 1000Hz, 2000Hz and 4000Hz. According to the result, the hole diameter, open area and the layout of concentric circle have a significant influence on TL.
NICE數-正方形與正立方體的切割
源自於Thinking Mathematically這本書的一道題目, 關於正方形的切割問題：將一個正方形切成不重疊的正方形, 所得的個數就可被稱作NICE(好的), 問有哪些數是NICE數？ 在平面的正方形切割的問題, 透過分割技巧, 我們得出了重要的結果：除了2、3、5以外的自然數都是NICE數, 並推導出：若k為NICE數, m為自然數, 則k+3m為NICE數。我們將問題推廣至立方體：將一個正方體切成不重疊的正方體, 所得的個數就可被稱作very NICE(非常好的), 問有哪些數是very NICE數？我們也得出重要的結果：大於47的自然數皆為very NICE數, 並推導出：若 是very NICE數, 且m是自然數, 則k+7m為very NICE數。
垂直水柱的成節機制探討
本研究欲探討垂直水柱遇障礙物成節的形成機制。以數位照相機、光電計時器等進行觀測。 實驗結果如下： （一）因往返水柱波速不同，而且節無波腹大幅振動現象，故節不是駐波現象。 （二）細針插入水柱表面時，當針上方超過某長度後，針下方產生Ｖ字形震波。但不論針相對水柱的速度是否超過波速，針上方都有節，故不是震波所產生的現象。 （三）根據水波槽模擬實驗，不論木條是否超過波速，木條前方均產生波紋。木條前方的水受到木條推動，往前方加速，因此顯現出波紋了。 我們認為，在水柱中所看到的節，不是震波或駐波，而是相對於木條往前傳遞的波。波源是撞擊物，改變了水柱表面的壓力，而成為波源，水柱的水因受撞擊，某個範圍內流速會小於波速，使得撞擊物前方存在波紋。This experiment uses digital camera and photoelectric timer to discuss the mechanism of causing spouts to form nodes on its surface. Because the downward wave velocity of the spout is different from that upwardand there are no significant vibrations of antinodes, standing waves are not the mechanism of causing nodes. In the experiment of inserting a needle into the spout, we found out that while the needle was inserted above a certain length of the spout, v shaped bow waves emerged. However, no matter the velocity of the needle related to the spout is over the wave velocity, there are always nodes above the needle. Therefore, bow waves are not the mechanism of causing nodes. According to the ripple tank simulating experiment, no matter whether the speed of the wooden stick is faster than the wave velocity or not, there are always waves forming in front of the wooden stick. The wooden stick pushes water in front of it and causes the water to accelerate forward. Therefore, waves appear. We think that the nodes we see on spouts are neither standing waves nor bow waves. The nodes are rather caused by the relatively moving wooden stick. The object, which impacted the spout (wooden stick), changed the pressure of the spout’s surface and became the source of wave. Because of the impact, the velocity of the water current of a certain area became slower than the wave velocity and causes nodes forming on the surface of the spout.
利用滾動實驗測量摩擦係數
A cylinder rolling on an inclined plane and a sphere on grooved tracks are discussed in details.Using elementary mechanics, the formulas are derived for the time interval (t) and the final speed (vas a function of release height (h). (1) A cylinder is rolling down an inclined plane. The speed and time of the center of mass ofthe cylinder which changed with position (x) are recorded by a motion sensor. We can get theplots of v vs. √x and t vs. √ x, and find that the acceleration of the center of mass of thecylinder is constant, whether the cylinder is in rolling or a combination of rolling and slipping. (2) A sphere is rolling down an inclined grooved track. The final speed at the bottom of thetrack can be calculated from the physics of projection motion after the sphere leaves the track to thefloor. The time t for the sphere starting from rest to the bottom can be recorded by using photogate detectors. From the v-√h and t-1/√h graphs, μs between the sphere and track can be obtained. (3) When a sphere is released from the vertical height h of a cycloidal slide, the time tof pure rolling is the same independent of release position. But, when the sphere moves at a combination of rolling and slipping, the time t' will be different from t. We measure t and t' with photogate detectors and get the plot of t vs. h. The value ofμs can be calculated from the t - h graph. 圓柱或鋼珠從斜面或有槽曲面形成的軌道上滾下時，利用基本力學，可推導出時間 (t) 、速率 (v) 隨高度改變的函數關係。 (1) 利用運動感應器記錄圓柱由斜面上滾下時，圓柱質量中心的速度及運動時間隨位置 (x) 的變化，可繪出 v 對√ x 及 t 對 √x關係圖，由v－√x 及 t－√ x圖可知不論圓柱純滾動或滾動兼滑動，其質心均等加速度運動。 (2) 鋼珠由有槽斜板滾下時，到達底端的速率可由從底端至地面的拋體運動算出，而其時間t則可利用光電計時器直接記錄，利用 v－√h 圖及 t－1/√ h 圖可求出鋼珠和軌道的靜摩擦係數 μs。 (3) 鋼珠從旋輪線上方純滾動至底端時，所經歷的時間 (t) 和釋放高度無關，但是當鋼珠滾動兼滑動時，所經歷時間 t' 會改變，利用光電計時器量出 t 及 t'並作圖，利用 t－h 圖可出 μs。
“氮”憑本事-土壤中單棲固氮細菌族群比例及親緣關係探討
Azotobacteraceae 為一單棲固氮菌科，包含Azotobacter 與Azomonas 兩菌屬，在農業上可用來改善缺氮的貧瘠土壤。在分離土壤中的Azotobacteraceae 時，發現非單棲固氮菌與單棲固氮菌間可能具有共生的情形。我們利用優勢培養(缺氮)的方法篩選土壤中的Azotobacteraceae，將優勢培養後所生成的菌落稀釋104~106倍後，能有效分離Azotobacter 與Azomonas，然而低於此稀釋倍率則會形成混合菌落，其中可同時發現單棲固氮菌與非單棲固氮菌存在，推測某些非固氮菌在優勢培養過程中可能可從單棲固氮菌獲得氮源，與之共生。此外亦從菌種形態的差異並配合顯微螢光雜合技術(fluorescence in situ hybridization, FISH)、分子遺傳標記(16S-rDNA)等方式，分析土壤中的Azotobacteraceae，探討單棲固氮菌及其他非單棲固氮菌在培養基上的生長情形、比例及親緣關係。The family Azotobacteraceace is group of free-living nitrogen-fixing bacteria that is found in soil. Two genera are within this family: Azotobacter and Azomonas. Agriculturally, it is often used to improve fertility for nitrogen deficient barren lands. We analyze the Azotobacteraceace according to molecular biology and traditional taxonomy. We used an enrichment procedure to culture the bacteria, and diluted it repeatedly. We found it most suitable to dilute it 104~106 times to best separate Azotobacter from Azomonas. If the concentration were to be higher than this, mixed flora containing many different bacteria species would be found. Moreover, we noticed that non nitrogen-fixing bacteria, symbiotic nitrogen-fixing bacteria, and free-living nitrogen-fixing bacteria would form a single colony on a nitrogen-deprived medium. This implies that a symbiotic relationship may exist between nitrogen-fixing bacteria and non nitrogen-fixing bacteria. We also discuss the growing situation, the group proportion, and the relationships between free-living nixtron fixing bacteria and other bacteria by morphology, fluorescence in situ hybridization (FISH), and molecular biology.