全國中小學科展

2013年

Building Bridges with Water-The Floating Waterbridge

This paper describes the investigation of a fascinating physical phenomenon called the “floating water bridge”. Despite the fact that water is undoubtedly the most important chemical substance on earth, it is practically ubiquitous and it still represents one of the best explored substances, still not all characteristics are well-understood. There are some phenomena like the “floating water bridge”, which cannot be explained. If high voltage is applied to two beakers, which are arranged close to each other and which are filled with deionized water, a connection forms spontaneously, giving the impression of a floating water bridge. For the experiment discussed in this paper, two beakers with a diameter of 50 mm and a height of 80 mm are filled with triply deionized water. Platinum electrodes are submerged in the center of the beakers, one set to ground potential (anode), the other one on high voltage, up to 25 kV dc. Within the scope of this work, an experimental setup was developed, which enables measuring and demonstrating the most important parameters like voltage, current, length and temperature of the water bridge as well as the mass transfer between the beakers. In addition the correlation between the different parameters and the influence on the water bridge could be estimated. Once the beakers are separated, the bridge remains stable for several hours up to a length of 2.5 cm. With platinum electrodes and no electrolysis observed, a small current (≈300µA), a mass flow from anode to cathode and forces were measured. Pictures, taken with an infrared camera and a new developed method to record "infrared-videos", enabled to visualize the heat flow in the water bridge. Furthermore the conversion of energy and the dependence of charge and mass transfer could be estimated roughly. In the course of the investigations it was also tried to prove the water bridge with other liquids like castor oil, olive oil, a mixture of glycol and water as well as tap water - for some of them for the first time. Supplementary the experimental setup was varied by using different electrodes with different sizes and different material as well as beakers of different sizes and materials. In addition, a qualitative explanation was developed. The results of this work enable a better understanding of the floating water bridge and provide a basis for further research as well as for development of future practical applications. One of these applications could be an improved waste water treatment process.

筆筒樹凋萎病防治法 -病原Ophiodiaporthe cyathease sp. nov.拮抗菌之篩選與應用

近在台灣新發現的筆筒樹萎凋病,造成大量筆筒樹(Cyathea lepifera)枯萎死亡,對於此疾病的防治已成亟需解決的問題。先前的研究中,已確認病原菌為新屬真菌並命名為Ophiodiaporthe cyatheae sp. nov.。本研究則在於以生物交互作用方式進行防治,尋找拮抗菌,針對特性實際應用。 研究中因實驗素材與操作方法的差異分為細菌與真菌類拮抗菌兩大主軸,且皆成功自土壤中各分離出數種有應用潛力的拮抗菌。細菌方面,尋獲並經鑑定為Burkholderia gladioli,對於病原菌有良好抑制效果,然由於此菌本身安全性有疑慮,實用上仍有待商榷。真菌方面,拮抗菌以超寄生方式與快速的生長能力制伏了病原菌,期待透過比較消除病原菌的速度,篩選出其中最強大適切的拮抗菌種,運用於實際田間病殘株處理。

有趣的切披薩問題

本次科展我們所探討的,是關於圓的分割問題,討論披薩被切出來的面積和及切痕的長度和等相關問題。 我們提出並且用較初等的數學方法證明了幾個與圓的分割有關的問題,包括披薩定理以及另外七個定理。 最後我們也利用GSP軟體驗證定理二、三、四分給2人時的對偶結果和定理二分給3人以上時的其他結果,並對於一般情形的推廣,作合理的猜測。

On Course Line Management

The Online Course Management system was developed in 2012 by George Moon to address the issue of creating course books at Burnside High School in Christchurch, New Zealand. The course books are designed to inform students, staff and parents of the many courses that are available for students to choose for their next year of study. In the past, the system that the school used consisted of large amounts of paperwork and duplication. Not only did this system require a lot of effort from staff, but the course book cost the school thousands of dollars to produce, as it had to be sent off to be published into a large book that would be read by students for a week, then likely thrown out. This year the school decided to digitise the course book, so that students would look at their courses online. Earlier this year, the school believed that the new School Management System (SMS) ‘KAMAR’ would be able to handle all of the necessary information, however this was not the case. Because of this, they needed a simple solution that would collate all of the course data, and then output it as a course book. I developed my project to do this. It is a web based program that is accessible by staff on their computers which enables them to enter in all of the course and assessment data for their departments. As it is all securely stored on a central database, it reduces duplication and staff workload, as well as the added environmental bonus of less paper being used. The program also outputs data in a number of ways including as a coursebook PDF (digital document which can be uploaded or printed), an Excel spreadsheet and a webpage for easy viewing. It can be sorted or printed by different categories (such as level, faculty, department), which proved to be a very useful feature. Following some research on areas such as design principles, browser compatibility and screen resolution (computer screen size), the program was designed to make best use of this this information. For example, most of the computers that staff would access the website on were of a similar size screen, so I made sure that my website worked well for them. I also used my research on design principles to try and create a simple, clean interface that users with limited computer skills would easily be able to navigate around. The outcome was real, as it was used by the school to generate their coursebook this year. Following a 95% student completion rate of course selection many months earlier than previous years, the system (although it had some issues) was pronounced a success, and the school is looking to use it in the years to come. There are a number of steps I am looking to take in the future with this program including the potential sale to other schools, so they can take advantage of the features it has to offer.

澱粉吸附蛋白質與澱粉糖的分子交互作用

顆粒澱粉可和碘形成藍色錯合物(starch-iodine complex),我從種子發芽澱粉酶實驗了解澱粉酶(amylase)具糖解酵素活性,會分解澱粉盤上的澱粉,並使澱粉失去與碘形成螺旋狀澱粉-碘錯合物的能力,讓藍色澱粉盤出現透明水解圈。通常澱粉酶之分子結構包含澱粉吸附區及催化區,分別負責吸附大分子或不可溶性澱粉糖(amylose)配體及分解澱粉糖成可溶性小分子糖。本計劃選用分子量、溶解度不同的澱粉糖分別與碘液反應,再加入澱粉酶(glucoamylase)或其澱粉吸附區(starch binding domain, SBD),發現二者均會破壞澱粉糖與碘結合之螺旋狀結構。分析二者之反應效率,可比較不同蛋白質解開澱粉-碘錯合物之能力。此外,本研究亦比較正常與突變株二聚體澱粉吸附區(SBD dimer)之解開澱粉-碘錯合物反應活性,再查詢文獻、比對不同蛋白質的序列、結構、及功能特性進行綜合分析。根據本研究結果,澱粉吸附蛋白質序列中解開配體螺旋結構最重要的官能基為兩個具有苯環的胺基酸,且二者對於可溶性及不可溶性配體之影響不同。本研究提供科學家了解自然界具備重複澱粉吸附區(tandem repeat)功能的邏輯方法,未來可應用於澱粉代謝、合成相關之蛋白質設計、結構預測、及功能分析。.

Microbial diversity in the Mediterranean hypersaline deep-sea lake Tyro

1. Purpose of the research Characterization of bacterial and viral diversity of brine Tyro using molecular methods of identification. 2. Procedures For bacteria: 1. Amplification or multiplication of 16S rRNA gene (one of the most conservative gene) by polymerase chain reaction (PCR). 2. Agarose gel electrophoresis and purification of PCR product 3. Ligation of purified PCR product into the vector pGEM-T 4. Transformation of plasmids containing an insert into competent cells E.coli XB1 5. Blue-white selection (we need white colonies, they contain the insert of interest) 6. Isolation of plasmids containing an insert of interest 7. Sequencing of inserts 8. Bioinformatics analysis: matching homologues from GeneBank database, construction of phylogenetic trees, statistical analysis. For viruses: The same methods were used for gp23 gene, which code a major head protein of T-even bacteriophages; to amplify gp23 gene a special set of primers was used, along with a standard cloning protocol described above. 3. Data 1) Two libraries of clones were obtained during analysis: lake Tyro (24 operational taxonomic units (OTUs), 10 classes) and sea water (6 OTUs, 2 classes of eubacteria). 2) The most abundant classes were: gamma-, delta-, epsilon- Proteobacteria, which is in agreement with previous reports about bacteria in brines of Mediterranean Sea. 3) The number of clones was not sufficient to obtain stable estimates of diversity, the analysis require additional data. 4) The diversity of bacteria was unexpectedly high in brine but not in the seawater, due to higher and more diverse ion composition. 5) Most of the detected bacteria in the deep-sea lake belonged to the previously undescribed (18,75%) bacteria or had unusual metabolism (43,75%). 4. Conclusions The analysis demonstrated unexpectedly high diversity of halophilic bacteria inhabiting Tyro lake. Most of bacteria presented in brine water had unique and uncommon characteristics based on information about its closest relatives. Therefore, the deep-sea hypersaline lakes of Mediterranean Sea have great potential for further investigations. Preliminary results of diversity of viruses of Tyro lake were obtained during analysis, more complete description is coming soon.

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.

具備節能協定之智慧型開關裝置的設計與研究

本研究參考智慧型3C產品之節能協定,將其應用於電源開關裝置上,此開關裝置將具備工作模式、待機模式及睡眠模式,利用此三種模式並結合即時輪詢的技術,發展出適合智慧型節能開關裝置的節能協定,達到全自動且節能的目標。此智慧型節能開關裝置主要包括固態開關電路、電流感測電路、RC濾波器電路以及控制電路,本研究針對上述幾種主要電路進行電路的研究及實作,並建立模擬的電路模型,根據此模型設計出完整的智慧型節能開關裝置,進行其節能效率及未來大量應用的可行性分析。經過實作證明,此種具備節能協定的智慧型節能開關的確能有效地省下家電待機耗電,與市面上不具備節能協定的開關相比,有更高的使用便利性。

Geo Air

1. Purpose: The purpose of this project was to design a theoretical tempered-air system to be integrated into an existing heating system in a home equipped with an air-to-air heat pump. This was to overcome the cost and environmental challenges of heating in cold climates as well as provide an environmentally friendly air-conditioning system in the summer at little to no cost. 2. Procedure: In the winter of 2010 an underground high-density polyethylene (HDPE) pipe (10cm diameter, and 30.5m length) was buried 2.5m underground around the footings of a new residential project. A fan with a flow of 3.4m³/min was attached to the pipe outside, and used to push air underground through the pipe and into the house. The ambient and incoming air temperatures as well as the date and time were recorded daily using a temperature probe with an error margin of ±0.1ºC throughout the summer and winter seasons of 2011. This data was then plotted and analyzed. A number of options to best extract thermal energy for potential use for heating and cooling were examined. Design components were selected to create an air chamber for an air-to-air heat pump to increase its coefficient of performance (COP). 3. Data: Graph 1 Graph 2 Winter Graph (Graph 1): The blue line represents the outdoor ambient temperature and the orange line represents the temperature of the tempered air. These are both arranged chronologically. The grey lines represent one standard deviation on either side of the incoming temperatures. The ambient temperatures vary dramatically, while the incoming temperatures remain quite stable. The lowest recorded temperature was about -9.0ºC, at which point the temperature exiting from the underground pipe was about 10.5ºC. Summer Graph (Graph 2): With dramatically varying ambient temperatures, the temperature of the incoming air consistently stays between 11.1 and 16.2ºC. The highest recorded outdoor temperature was about 30.0ºC, while the incoming temperature at that point was about 15.5ºC. This cold air was used as air conditioning.

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: