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Bio-Active Plants

My Science Fair project last year tested a local native plant for it’s toxic effects on insects (fruit flies), bacteria, fungi, and viruses. The root of the plant Lomatium dissectum, had been used by the Salish People to control lice and other insect pests in horses and cattle. The root was also used to kill fish, which could then be harvested by women and children. The fish killed in this way were not harmful to eat as long as they were consumed soon afterward. I have found also that fishing with the aid of plant toxins was formerly very common in tropical Africa. \r Lomatium dissectum, grows in dry rocky slopes in conjunction with Sagebrush.\r Many desert plants produce toxic substances that inhibit the growth of competing plants\r nearby. This adaptation is called Allelopathy. In a natural ecosystem, Lomatium does not\r kill fish because it does not grow beside creeks. But this raises the question of whether\r allelopathic plants growing outside their natural ecosystem are having a toxic effect on\r animal life. There are introduced invasive weeds that are allelopathic, such as\r Knapweed,growing near streams. And there are crop plants that are allelopathic – Rye and\r Alfalfa. Do these “natural herbicides” also kill fish? Walnut trees are allelopathic and\r compounds from Walnut kill fish.\r If this effect does go beyond toxicity to other plants, it would be an important\r consideration to environmental guidelines for private land bordering on streams and\r rivers. The B.C. Ministry of Environment notes the importance of shade cover for\r spawning streams. It does not recognize the harmful effects of introduced plants. Yet,\r when we were purchasing supplies for our Koi Pond the pet supply company offered a list\r of “Some of the Worst Plants to Have Around Koi”. We do not know if the introduced\r allelopathic plants are poisoning fish or reducing fish stock by poisoning the food that fish\r need.\r Science Fair rules do not allow any research that is expected to have any negative\r impact on vertebrate animals. Because of this, I have decided to test the effect of\r allelopathic plants on fruit flies (Drosophila). Fruit flies are similar to fish since, during\r larva and pupa forms, they live in direct contact with their culture media. I will also be\r testing the effect of allelopathic plants on Planaria (Turbellaria), an aquatic invertebrate.

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單汽缸二行程高轉速引擎扭力延伸

The paper is to research the method how to prevent the torque down under the higher rotation of the single cylinder with two stroke’s engine and increasing the engine’s torque oppositely. By the process of adjusting (1)changing the weight and the position of the balance block(2) adjusting the exhausting time of the outlet valve(3)to decrease the weight and structure of the crank itself adequately. it is find that the engine’s torque was increased at the situation of higher rotational engine. After the adjusting of the process we have the following result:(1)at the higher revolution zone of the engine. the torque can be maintained and increased(2)the higher revolute efficiently value can be obtained by the correct adjusting of the exhaust time of the outlet valve without increasing the fuel.本研究主要是探討單汽缸二行程高轉速引擎在高轉速時扭力能延遲下降,使扭力增加。我們是利用二行程引擎高效率的結構和現有空間來提升引擎效能。經(1)改變曲軸配重塊之重量及位子移動 (2)調整引擎排氣時間 (3)適度減輕曲軸重量及結構等三項,改良後證明,確定能使扭力提升,和延伸到較高的轉速區。經過調整程序,可獲下列重要結果:(1)在引擎高轉速時,可增加較大的扭力值 (2)藉由適當的排氣時間調整,在不增加燃油供給條件下,可獲得較高的迴轉效率。

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黏質色拉雷菌(Serratia marcescens)發光重組菌偵測環境中含酚環之毒性化合物之?

A pair of bacterial two-component system RssB-RssA was cooperated into Serratia marcescens for toxicity phenolic compound detection. First step of this study, E coli was used to accept the plasmid and certified by fluorescent. Then transfer the system from E coli into Serratia marcescens. Finally, 7 kinds of chemical, included phenol, benzene, toluene, xylenes, 4-chlorotoluene, 2-nitrotoluene, and kerosene, were used to check the sensitivity of this gene modified Serratia marcescens line. The results showed that this gene modified Serratia marcescens line had good performances and responses to those chemicals. 本實驗是以一受到二元訊號傳遞系統調控的發光基因重組質體,送入黏質色拉雷菌中,並以製備好的菌株進行毒性化合物之測試。在實驗的第一階段,我們將重組質體送入大腸桿菌內,並以其發光的有無來判斷是否達到送入的目的,其後再以電泳法確認各基因片段是否正確。第二階段再以相同的方法將選殖好的重組發光質體送入黏質色拉雷菌。第三階段,以發光重組菌針對酚、苯、甲苯、二甲苯、4-氯甲苯、2-硝基甲苯及煤油進行發光測試。結果方面,我們發現黏質色拉雷菌發光重組菌對於這一系列的酚環類化合物的確具有相當高的敏感度。

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半屏山之簷下姬鬼蛛的研究

The spiders, Neoscona nautica, often appear in groups, but individuals have their own sense of territory.They usually spin webs among branches during 6:00~ 8:00 in the evening. When building webs, they will first start with bridges and then spin Y-shaped spokes. Next, they spin meshe of net, silk frame, spokes, spirals and free-zone in order. After finishing webs, they will wait for prey on the free-zone or meshe of net. If they find something inanimate on the web, they will break the spiral attached with the inanimate object that is later removed. If the meshe of net is broken, they will fix it immediately. For them, the time to take webs back is during 2:30~ 6:00 in the morning. Most time they use the first pair and the second pair of legs to take webs back and swallow the webs. Sometimes, they break the spirals by the last pair of legs. The sequence to take webs back is : lower right section, lower middle section, lower left section, upper left section, and upper right section. At last, one thread of bridge will be left. Every early mornings they take webs back and swallow them. The next evening they rebuild webs. Possibly there are two reasons to explain why spiders eat their webs: (1).They swallow webs to get protein. (2).The web threads are easily polluted by dust and humidity and reduce stickiness. The web may also reduce the probability of capturing prey. The body length of them is not related to effective web dimensions. However, the web sizes depend on the width of web-building location. The study shows linear relation among body length, meshe of net and dimensions of free-zone. The linear relation represents that the meshe of net and free-zone have ecological or survival meaning for them. We expect that this study of Neoscona nautica can be helpful to build spider ecological database in Taiwan.簷下姬鬼蛛常成群出現,但個體卻有很強的領域性;常於下午6:00 至8:00 結網於樹枝間,結網時,先以橋絲為出發,織出一Y 形的縱絲,再由此依序織出中空網眼、絲框、縱絲、橫絲、棲息圈,網結好後,簷下姬鬼蛛則在棲息圈或網眼靜候獵物,若發現網上有非生物之異物,則將黏住異物的橫絲弄斷,再把網上的異物丟棄;若網眼被破壞,則會立即修補。收網時間為凌晨2:30 至凌晨6:00,收網時,大部分由第一、二對步足進行收網,偶爾會用最後一對步足將橫絲弄斷,一邊收網一邊將網吞食,收網的順序為:右下、中下、左下、左上、右上,最後留下一條橋絲。簷下姬鬼蛛每天清晨都會收網,並將網吃掉,翌日傍晚再重新結網,其可能原因有兩點:(1)將網吃掉以補充蛋白質。(2)蛛絲容易受灰塵、水氣之污染而減小黏性,降低獵捕功效。簷下姬鬼蛛體長與有效網面積無關,但網的大小視其結網地點寬敞程度而定。體長與網眼、棲息圈面積呈線性關係,表示網眼和棲息圈對簷下姬鬼蛛具有生態或生存意義。我們對簷下姬鬼蛛生態調查之結果,希望能幫助台灣的蜘蛛生態資料庫之建立。

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太陽能熱動力發電與效益的改進方法

在綠色能源中太陽能的利用充滿了無限的機會,其中利用太陽熱能發電的太陽能煙囪觀念有很大的潛力。在本研究中,我們以實驗的方法討論煙囪高度、入風口大小、管型等因素對solar chimney 效益的影響,發現就原先的觀念設計中,有相當大的改進空間。整體實驗而言,所改變的各項變數中,以管型之改變有最大的改進效益。就同長度直管與漸擴管而言,漸擴管在風速上有明顯改進效果,且以流速與截面積換算成效率,較原直管設計之效率高出約20 倍,因此推測漸擴管應用在現行之solar chimney 以改進效能是極有可行性的。研究中也發現煙囪管壁的熱傳導也會影響氣體的總體流動,使效率降低。相信此實驗之數據對日後嘗試對solar chimney 進行改進的研究者有相當之參考價值。Solar energy has a great market potential among many clean energies. The new solar chimney concept using solar thermal power in power generation may have a bright future. Experimental work was performed to study the energy conversion characteristics of a solar chimney. The air moving capability and the influences of chimney height, the shape of chimney and air entrance dimension were studied. It was found that there is a great room to improve the current solar chimney design and thus the efficiency. Overall speaking, the chimney pipe geometry may have the most significant impact on the improvement of performance. A diverged pipe configuration can induce nearly 20 times more flow than a traditional straight pipe. Another finding is the heat transfer effect on the chimney pipe may have the effect in reducing the flow. It is believed that the present study0 is valuable for those people in designing a future solar chimney.

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台灣沿岸地形與海嘯的實驗室模擬

本實驗利用喇叭、薄膜電極、波型產生器、鎖相放大器、及750 介面卡組合一套系統,此系統可使偵測精密度大幅提升(±4*10-5cm),使得水槽及地表模型尺度變小(40*22*35cm),因此可節省實驗的成本與時間我們在坡度實驗中,發現坡度在3 度左右,淺化係數都超過3. 對照台灣沿岸發生海嘯的歷史記載,確實在台灣東北角及西南沿岸等坡度為三度之地區都發生較明顯的海嘯危害. 反之,坡度在四度以上的東岸其海嘯波高都非常低.最後再藉著硬體系統及電腦2D 動畫模擬的整合,使我們可方便掌握波浪在不同坡度及位置,其波長及波高變化比,如此有助於預估及說明海嘯隨地形變化的狀況.By using the horn, membranous electrodes, function generator, phase-locked amplifier, and Science Workshop 750, we plan to assemble a tsunami simulation system in which the precision can be getting increased (±4*10-5cm) .Because of the improvement of its precision, the size of the tank and of the surface models will become smaller .As a result, the money and time spent on the experiment will be spare. When experimenting on the influence of inclination of the landforms, we observed that when the inclination reaches about 3 degrees, the shoaling coefficient exceeded 3 .The result of our experiment can provide an explanation to the tsunami on the northeast and southwest coast of Taiwan .According to the historical records, the disastrous tsunami happens frequently on the northeast and southwest coast of Taiwan where its inclination is also about 3 degrees as well .On the other hand, on the eastern coast, the wave height is lower and its inclination exceeds 4 degrees .Apparently, our experimenting result is correspond to the natural phenomena in Taiwan’s coast . Besides, with the help of hardware system and computer 2D animation simulation, we can easily measure the wavelength and wave height scale of the wave in different inclinations and positions. Therefore, this tsunami simulation system can provide a great help to estimate and explain the phenomena of tsunami which may change its condition in different landforms.

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『吸凍!』--再造保麗龍的第二個春天

中文摘要 本實驗先尋求將廢棄保麗龍磺酸化為陽離子交換樹脂(本實驗稱”保麗龍膠”)的方法。將保 麗龍依:丙酮溶解→硬化→打碎→與濃硫酸共煮三小時→浸於50%硫酸溶液中→沖洗→以水 浸泡的流程,即可達再造的目的;我們測得其磺酸化比例為62.5%。再利用「碘滴定法」(浸 泡式)與「相對電壓檢測法」(流動式),依次尋求保麗龍膠吸附金屬離子的最佳條件。其中「碘 滴定法」可有效測出銅離子濃度,但手續繁瑣;「相對電壓檢測法」最大的好處是知道保麗龍 膠何時吸附達飽和必須再生。 目前我們所知,要保麗龍膠達到吸附陽離子的最佳效能,其條件依次為:使用細粒的保 麗龍膠;低濃度的金屬離子溶液;質量愈大的保麗龍膠;低溫下較慢的金屬廢水流速及pH 值約為4.30 的銅離子廢水;鈉型的保麗龍膠吸附效能優於氫型。保麗龍膠對不同金屬離子亦 有吸附力,單位體積所含離子數愈少,初始的相對電壓會愈高;在相同莫耳濃度下,不同離 子的吸附力依次為Cr3+>Fe3+>Ni2+>Cu2+>Co2+;分次吸附確可將金屬離子完全去除;由 吸附等溫線觀察得知,可能保麗龍膠為多孔物質,導致500ppm 以下的吸附模式無法明確判 斷,1000ppm 以上則為物理吸附模式;保麗龍膠可以再生也可被覆在砂粒上達到不錯的吸附 效能;最後,我們將吸附過金屬離子的保麗龍廢膠與硫酸鈣、紙漿及些許的石灰(質量依序為 13 克、13 克、7 克、0.04 克)混合,可製成類似紙黏土,做成造型磁鐵,廢物利用十分有趣。 Abstract The Experiment will, first of all, explore the ways to sulfonate expandable polystyrene into cation ion exchange resin (called “polystyrene rubber” hereafter in the experiment). The procedures of treating expandable polystyrene are as follows: acetone dissolve→hardening→smashing→ boiling with sulfuric acid for three hours→immersing in 50% sulfuric acid solution→washing→ immersing in water so that we may reach the goal of reconstruction. We calculate the sulfonated rate to be 62.5%. Then we make use of “Iodine Titration”(immersion method) and “Opposite Voltage”(floating method) to seek for the best conditions of adsorption the metallic ion through polystyrene rubber. The former can effectively calculate the concentration of copper ion, but the procedures are quite complex. The greatest advantage of the “Opposite Voltage” method is that we may know when the adsorption of polystyrene rubber is saturated and should be regenerated. As far as we know at present, the conditions of obtaining the best effect that polystyrene may adsorb the cation ion are as follows: fine particles of polystyrene rubber; low concentration metallic solution; polystyrene rubber of which the mass is greater; at lower temperature, slower waste water flow speed and the copper ion waste water with pH 4.30; the adsorption effect of sodium type polystyrene rubber is better than the hydrogen type. Polystyrene rubber also has adsorption effect toward different metallic ion. The less ion per cubic contains, the higher the original opposite voltage. With the same mole concentration, different ion adsorption effects may range as follows: Cr3+>Fe3+>Ni2+>Cu2+>Co2+. The batch adsorption definitely may erase metallic ion completely. By observing the adsorption isotherm, possibly because the polystyrene rubber is a multi-apertured matter, we find that it is impossible to judge exactly the adsorption model of those metallic ion solutions of which the concentrations are below 500ppm. Those which are over 1,000ppm belong to physical adsorption models. Polystyrene may be regenerated and get an adsorption effect by coating sand particals. In the last analysis, we may make paper clay and magnets of different styles by mixing the adsorbed metallic ion polystyrene rubber with calcium sulfate, paper pulp and a little lime(the mass are respectively 13g, 13g, 7g, and 0.04g). The reuse of waste is really very interesting.

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攔截未知病毒之基礎技術-參數監控

在網際網路蓬勃發展的時代,電腦病毒也更加的猖獗。雖說防毒軟體百家爭鳴,但對於未知病毒的防治技術仍然束手無策。本研究的目的在追溯出電腦惡意程式運行模式,利用IDA靜態反編譯軟體與病毒原始碼尋找出病毒共同的特徵,阻斷其滋生途徑。 本研究在實驗中,研究者利用Borland C++ Builder 6作為應用程式開發環境,配合WinAPI函數與TRegistry類別設計出參數監控系統。研究顯示不論是修改於Window 9x架構下的win.ini, system.ini,或是Run與Run Service之下的資料項,本系統都能有效運作。此系統能成功的攔截到惡意程式對Registry鍵值的讀寫,亦即當使用者否決其修改鍵值時,惡意程式無法在重新開機後運行;易言之,惡意程式失去執行效力。 實驗結果發現,參數監控系統可攔截惡意程式之修改命令,防止未知病毒與惡意程式開機自動運行,以此達到未知病毒的攔截基礎技術。本研究之結果可補強市售防毒系統,對於未知病毒的攔截,能達到完整的防護效果。 Computer viruses become more rampant in the rapidly-developing era of Internet. With the various kinds of Anti-Virus software, people still can do nothing about detecting the unknown viruses. This research aims to trace back the computer virus function mode. By using IDA Pro Disassembler and Virus Source, we can find out the common characteristics of viruses. Thus, we can stop viruses from thriving. The experiment uses Borland C++ Builder 6 as the Registry Detection System by coordinating Win API and TRegistry. It works no matter by modifying win.ini and system.ini under the structure of Window 9x or by modifying Run Value and RunService Value. Moreover, it can intercept the viruses from reading and writing of the ValueKey. As the users deny the modified ValueKey, the viruses cannot run after resetting. In other words, the viruses lose their effects. The results present that Registry Detection System can intercept the modifying commands and prevent the automatic running from unknown viruses. By doing so, we can acquire the basic technology of intercepting the unknown viruses. The application of this study can improve the functions of Anti-Virus. In this way, through protection from unknown viruses can be obtained.

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High Speed Size-exclusion Chromatography (SEC) Using Spherical Meso-structured Cellular Foam (MCF)

Size-exclusion chromatography (SEC) is often used to determine the molecular weights of and separate polymers and proteins. The porous packing of the SEC column effects the separation of molecules, with larger molecules eluting earlier. Interest in high-speed SEC for larger molecules has been building, especially for combinatorial polymerization reactions and online SEC-MS applications. Mechanical stability of the packing, which siliceous materials have more of than polymeric ones, therefore needs to be improved. Several silicas have been explored but limited pore sizes and pore volumes have restricted their usage to separating small molecules. Siliceous MCF templated using oil-in-water microemulsions has good potential for SEC packing because it has ultralarge pore size (20-50 nm), high porosity and sturdy skeleton. However conventional MCF consists of highly irregular particles and hence cannot be used as packing.

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Palatability Tests on Rana Chalconota Tadpoles

The skin of amphibians can secrete poisons from glands which reduces Palatability or sometimes result in rejection by predators. My research serves to confim the hypothesis that the pair of glands located on the ventral side of Rana Chalconota Tadpoles acts as an anti-presatory structure. Their palatability was measured by the consumption of them at developmental stages intermediate and post-metamorphic by Channa gachua and Giant Dragonfly Nymph. A known-palatable tadpole, Rana malesiana, was used as a control.

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Crying Babies

a. PURPOSE: Do babies between 0 – 3 months have certain sound reflexes that can be interpreted as a language? Can parents be helped to understand their newborn babies better? Are parents aware of infantile speech patterns and language acquisition in babies? b. PROCEDURES: 70 Babies of different cultures were tested to determine if the 5 crying-sounds can be an indication of the baby's need. Questionnaires and information were given out at hospitals and clinics. Doctors, paediatricians, sisters and parents were involved in my project. DVD's were made to show and explain the different sounds. c. DATA: I obtained my data from the questionnaires, interviews with parents, doctors, paediatricians and the staff working in the labour-wards. 70 Babies were tested (68 responded) and I listened to every cryingsound to make sure that there are only 5 different sounds. I made a DVD from all the sounds of the babies that I've tested. Data were also gathered from science. d. CONCLUSIONS: According to all the research and sources, I can positively say that a person can identify the reason why babies (0-3 months) are crying. Babies of any culture, have universal sounds that indicate their needs. The different sounds are: EH – upper gas, EAIRH – lower gas, HEH – discomfort, OWH –tired, NEH – hungry.

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液晶面板在不同電場下穿透光譜之研究

本研究主要是探討液晶面板在不同的電壓下,對紅外光區及可見光區之穿透光譜。藉由控制外加液晶面板兩側的電壓,改變內部的電場強度,驅使液晶分子長軸方向改變(偏轉),以達到控制穿透率之目的。施加於液晶面板兩側的電壓V大於起始電壓V0時,液晶分子長軸受電場作用與電場方向平行,減弱引導偏振光扭轉之能力,讓部分光通過偏振片。令及分別代表穿透率達到最大穿透率之10%及90%時的外加電壓,則定義「光-電開關斜率」γ為:γ =(V90-V10)/V10。透射光強度與外加電壓關係曲線則稱為「光-電開關特性曲線」。穿透率除與液晶分子之旋光程度有關,我們也做了在不同電壓下,液晶分子之穿透光譜,並討論其特性。The main idea of the project is to discuss the transmittance spectra of liquid-crystal device in the range of infrared and visual light (400~900 nm) with different electric field by changing voltage. Different biases are applied to the liquid-crystal cell, causing the axis of liquid-crystal to rotate, and the transmittances are measured. If the application of bias is greater than the threshold voltage (V0), the axis of liquid-crystal will be parallel to the electric field, and make the beam pass through polaroid. Electro-optical switching slope γ is defined as γ =(V90-V10)/V10 , where V10 and V90 are the applied voltages enabling output light signal reaches up to 10% and 90% of its maximum intensity, respectively. It is understood that transmittance depends on the optical activity of liquid-crystal cells. Besides, we will discuss the relation between wavelength and transmittance of liquid-crystal cells.

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