吸管笛的諧音之研究與發展
吹長笛時，按同一按鍵，以大小不同的力量去吹，會引發不同頻率的泛音，而通常越用力吹，引發泛音的頻率越高，所以我們想了解為什麼越用力，泛音的頻率會高，其間的關係究竟是什麼？風經過管口會產生各種頻率的噪音，其中某些特定頻率的聲音會因為會在管內形成駐波而放大，所以我們只能聽到某些特定頻率的聲音。當風速增加時，會在管口形成渦漩逸放的紊流現象。其渦漩頻率與流速成正比（註一）。我們以塑膠管實驗。發現以特定的風速引發該基音後，繼續增加風速，當風速達某一定強度時，才會躍遷為下一個泛音的頻率。這個現象告訴我們：在一封閉管下，風速與泛音的關係並非「線性遞增」，而是越「躍遷遞增」的關係。另一個實驗測量不同管長、其諧音之頻率的關係，我們可以得知，越短的管子，因為相鄰兩泛音間頻率差較大，越不易激發更高階泛音。經由這些實驗結果，我們能夠推論：當管子越長、基音頻率越低時，諧音間頻率的差距相對越小，繪出的風速－頻率關係圖應更加顯示了風速與頻率呈正比關係。未來我們可以以閃頻器觀測紊流渦漩的產生，再變化至不同吹入角度，及各式管口造形，這些實驗能協助我們更進一步了解樂器的發聲原理，甚至開發一個以聲音頻率測量風速的儀器。註一：林婉如、張?文2006 國際科工程組佳作作品。When we press the same key and blow a flute using different strengths, we can get different overtones. Usually, the harder we blow the flute, the high the frequency we get. We want to understand why we get a higher frequency when we blow harder into the flute and to understand the relationship between them. When wind passes through the mouthpiece, many kinds of noises will be produced. Some of the frequencies will expand because they will form standing waves in the tube. Therefore, we can only hear certain frequencies. As wind speed increases, a turbulence of the vortex shedding will be formed. The frequency of the vortex shedding and wind speed will be in a direct ratio. We experiment with plastic tubes. When we increase the wind speed and get certain magnitudes, the frequency will jump to the next overtone. The phenomenon shows that the relation, in a closed tube, between wind speed and harmonics is not a linear increase but a transition increase. In another experiment, we measured the relationship between wind speed and different lengths of tubes. We can infer that the shorter the tube, the higher high-frequency harmonics can be produced. Through these experiments, we come to the conclusion that the longer the tube, the lower frequency of the fundamental tone we get and the discrepancy in frequency between harmonics is smaller. Then we make a diagram between wind speed and frequency that indicates that there is a direct ratio between wind speed and frequency. In the future, we can use “” to observe the production of turbulence. Then we can switch to different angles when we blow into flutes. Otherwise, we can experiment with different shapes of mouthpieces. These experiments can assist us to understand more how the instrument sounds. We can develop a device measuring wind speed with frequency.
國王的海市蜃樓
在夏日的午後，在炎熱的柏油路面上很容易可觀察到遠方的 路面上，出現如鏡子般的倒影，看起來彷彿前方有一灘水，但當 我們向前進一些時，倒影卻突然消失了，這個現象，一般稱為海 市蜃樓。 一般解釋海市蜃樓的成因，都是由於在上層的低溫空氣，和 在下層靠近路面的高溫空氣，因密度的不同，以致於折射率的漸 層差異，繼而產生全反射。 但我們觀察發現，地面與上層空氣的溫差，並非柏油路面上 假積水現象及倒影出現的必要條件；反而和入射光的角度、路面 的平坦程度及路面的性質有關。我們提出了粗糙面在入射光的入 射角接近90度時，可發生單向反射的模型。並由實驗來驗證假積 水現象及倒影主要的成因是「柏油路面的單向反射」而非「空氣 的折射與全反射」。 Under the scorching sunshine, we can see the reflection on the tarmac in the distance just like a water puddle on the road. And the water also reflects the people and object nearby. But, in fact, the tarmac road over there is very hot and dry. Therefore we call the phenomenon as the “false water puddle on the tarmac.” According to the textbook , the main reason for “false water puddle on the tarmac” is that the temperature difference leads to the refraction of the light and causes the phenomenon. However, from our observation, the theory still can’t explain some phenomenon, For example, the “false water puddle on the tarmac” remains to appear when the wind blows fiercely. Even with little temperature different at night the phenomenon is still obvious. Therefore, in our opinion, the temperature different of the air is not a necessary condition of “ the false water puddle on the tarmac.” We bring up the model to explain the phenomenon that when the incident angle of the light approach 90 degrees, the light will result in one-way reflection. According to the model, furthermore, we make experiments at midnight and at dawn. The result of the experiment assures us the hypothesis of the model, Consequently, we hold the ideal that the main condition of the “false water puddle on the tarmac.” Is not because of the refraction and the total reflection but because the light reflects off the road and result in the one-way reflection on the tarmac road.
西瓜成熟與否和聲音關係
一般人從小就知道如果要判斷西瓜有無成熟，只要用手輕拍瓜皮，利用聲音的特性就可以知道西瓜是否成熟，此技術看起來容易，卻需有多年經驗之西瓜商始可為之。本研究利用拍擊西瓜所造成之聲音進行非破壞性音波檢測，來探討西瓜之成熟度。換言之，本研究希望在依照西瓜商拍擊的習慣下，從客觀的科學角度，探討存在於西瓜商手上「聽音辨瓜」的奧秘。由研究結果得知，西瓜的拍聲在頻譜中可分為三個頻區，即西瓜殼所造成的高頻區，水及含水量高的果肉所形成的中頻區，及由空洞及含水量低的果肉所造成的低頻區，而西瓜商就是藉由這三種音頻所表現出的綜合效果進行判斷。The method, tapping the watermelon rind and listening to the sound, has been often used to judge whether the watermelon is mature or not. Although it is not difficult to tap the rind of a watermelon, it is not so easy to have a correct judgment of the maturity just from the sound you heard, unless you are an experienced watermelon farmer. In order to investigate the secret that the farmers have, this research detects and analyzes the sound of tapping watermelons in an objectively scientific way. According to the experimental results, the sound could be approximately partitioned into three regions in the frequency spectrum, denoted as high-frequency, mid-frequency, and low-frequency regions. The high-frequency region and mid-frequency region are resulted from the hard solid rind and the juicy flesh of a watermelon, respectively. As for the low-frequency region, it comes from the vacant holes or flesh with little amount of water. Based on the experiment, it can be concluded that the maturity of a watermelon can be correctly judged from the combination of these three frequency regions, just like the farmer’s method.
分子篩包覆奈米銀製作與應用
本實驗合成之奈米銀粒子產物分為水溶液與固態形式。奈米銀粒子水溶液態製造方法以多芽基之檸檬酸根離子當保護劑，再以NaBH4 還原生成奈米銀粒子。而固態形式之奈米銀粒子是先以四級銨鹽界面活性劑當保護劑，經過NaBH4 還原生成奈米銀粒子水溶液後，再用二氧化矽包覆奈米銀粒子，藉由高溫燒去保護劑，得到含奈米銀粒子之二氧化矽分子篩材料。 將含奈米銀粒子之二氧化矽分子篩材料產物浸在純水中，除了不會改變水溶液性質外，又能以分子篩通透的特性，讓奈米銀漸進地釋放出銀離子，而達到長效性抗菌效果。 至於具抗菌性棉衫或濾網的製作，則採直接浸泡在奈米銀粒子水溶液中的方法，使奈米銀粒子吸附於上，針對上述實驗非常成功，洗滌超過十次且放置時間長達一個月以上，其抗菌效果仍佳，表示此簡易法製成的棉衫或濾網具有長效性的抗菌功效，為本研究重大突破。 奈米銀粒子對環境的影響是利用黑殼蝦來測試，控制適當奈米銀粒子濃度，使黑殼蝦能生存，亦可達到水中殺菌的效果。本實驗為首次針對奈米銀粒子對環境影響的測試並獲得重大的成果。;In this study, two Ag nanoparticles samples including Ag nanoparticles in aqueous solution and in solid form were prepared. The Ag nanoparticles aqueous solution readily obtained from reduction of AgNO3 aqueous solution with NaBH4solution in the presence of the sodium citrate as protecting agent. To prepare the Ag nanoparticles@porous silica sample, cationic alkyltrimethylammonium surfactant was used as the protecting agent of Ag nanoparticles and template of the porous silica. The Ag nanoparticles@porous silica was synthesized via reduction by NaBH4, silicification in silicate solution and calcination for the removal of surfactant. When adding the Ag nanoparticles@porous silica, the property of the aqueous solution was not changed. In addition, the Ag+ ion was gradually released from the accessible silica matrix to achieve a long-lasting effect on anti-bacteria. To prepare anti-bacteria clothes and sieves, these objects were soaked in Ag nanoparticles aqueous solution. The Ag nanoparticles were spontaneously absorbed into the clothes and sieves. The anti-bacteria efficiency of the Ag-nanoparticles containing clothes and sieves still remains even after ten-time washing and a period of time longer than one month. These worthy results indicate that this synthetic method provides a simple way to prepare the long-lasting Ag-nanoparticles containing clothes and sieves for anti-bacteria application. To investigate the influence of the Ag nanoparticles on the environment, shrimps are used as testing objects. With a well control on the Ag nanoparticles concentration, the shrimps survived well and the bacteria content was reduced. It is the first time to have testing result about the effect of the Ag nanoparticles on the environment. Thus, this is the most remarkable achievement in our experiments.
聽聽貝多芬作品的下一代：將碎形及基因演算法應用於數位音樂產生器
本研究整合了碎形圖形的迭代運算方法與基因交配觀念來達到音樂創新，並透過音樂和諧性判別機制來提高創新音樂的悅耳程度。利用基因觀念之交配的方法來解決長短的問題。這個方法是把原始音符輸入後，找出它們的中心點，以這個中心點為準，其他的音符按照一定比例向外延展，成為新的迭代點。再利用這些迭代點，迭代出新的音符。把製造好的音符染色體放置到交配池中，以隨機的方式在交配池中選取其中之一個染色體進行交配的動作，此二音符染色體會交換彼此的基因，產生下一代新的代表音符長短之染色體，隨後以「模仿母體判斷式」來判斷這新一代的音樂是否與母體音樂相似，藉此淘汰掉「不肖的」下一代，而若新一代與母體的相似程度高的話，它的悅耳性相信也會相對提高。最後把這些技術應用於數位音樂創作，以衍生新穎應用與創新的結果。Fractals can be produced by IFS (Iterated Function Systems). By iterative computation of many times, we can obtain the similar graphics. In my research, the methods to generate the iterative algorithms were presented. In addition, I would discuss the regularity and the content as well as the properties of those digital patterns. At last, the advanced application of fractals to digital music pieces was presented. The program took a note of several measure of music as the beginning point, and made the IFS calculations for each new note in each measure. But there was no difference in beats if you just make the IFS iteration. So I changed the beats with genetic crossover method. In this research, the expression of the DNA to each beat of note was adopted. The same way, it took a note as a beginning point. And the system obtained the new DNA from the old notes for new ones randomly. After producing the new pieces of music, I want to know if it is good to listen. So I used the algorithm that checks the simulation to the shape of mother music. If its shape is similar to the mother music, the probability that the new music is pleasing may even increase. That would make a piece of brand new music. What I want to do in this research is improve the multiformity of music and find what the relationship is of ‘good music’ and mathematical algorithms
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.
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.
以離子溶液催化醇與酸酐的之酯化反應
在酯化反應中，經由實驗結果，我們發現離子液體對於此反應有催化的效果。離子液體 是在室溫下呈現液態的離子化合物，將醇類與酸酐放入離子液體中有助於酯化反應的進行， 基於這個新的發現，我們開始尋找使用不同種類的離子液體做實驗，選出適當的離子液體， 並且測試離子液體在不同環境下的催化效果，以及適合的使用計量；更進一步，我們找出離 子液體在催化反應之後，將離子液體回收的方法：利用有機溶劑將離子液體和產物分層並萃 取出產物，把離子液體回收再利用，符合現代推動綠色化學的趨勢。接下來我們探討離子液 體對催化反應的擴展性與應用，先由不同結構的一級醇反應到醯胺鍵的生成，最後推展到合 成阿斯匹靈，實驗結果說明，用離子液體做催化劑，也可以成功的合成阿斯匹靈。 We have established for the first time that ionic liquids, which possess the property of Lewis acid, can facilitate acylation of alcohols with anhydrides to form esters with photo-excitation. With the initial finding, we then screen through different types of ionic liquids with varying counter anions, loading, and external light or heat sources to sort out the best reaction conditions. To gain insights into the working mechanism, the dynamic profile of the catalytic reaction was monitored by analyzing the reaction mixture by using ‘H NMR spectroscopy. The ionic liquids can be recovered by extractive separation from the acylation product, which meets the major theme of green chemistry. To extend the substrate scope and applications of the new catalytic process, different functional primary alcohols and amines were further examined. More importantly, we have utilized the new catalytic protocol for the acetylating of salicylic acid, leading to aspirin with high efficiency.