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.
超音波霧化降溫之研究探討
本研究（超音波霧化降溫研究）由二實驗組成。實驗一主要針對超音波霧化器（以下簡稱霧化器）之造霧性能進行探討；實驗二則為霧化器之降溫應用。實驗一以改良傳統造霧方式，進而維持最佳造霧效果為主。由於先前的霧化方式是直接放置霧化器於水面，致使最佳霧化水深因霧氣蒸散、水位下降而無法維持；所以在實驗一裡，我們針對霧化器的使用設計一套「漂浮造霧法」：本法運用浮體使霧化器懸於水面，和水面等起伏，使霧化器底部距水面高度不變，藉以維持最佳造霧水深、造霧效果。實驗二乃霧化降溫之探討。本實驗在相同的霧化量下，操縱風速和接觸表面積的差異；利用霧、氣接觸面積與蒸散速率呈正向關係的原理，找出最佳的降溫條件。同時，也期待在兼顧環保的前提下，將之應用於未來開放空間的降溫。The research（Heat Control by Supersonic Vaporization）includes two experiments. One is focused on atomized effect of Supersonic Vaporization（so-called Atomizer）; the other is about applying atomizer to temperature decrease. Exp.1 adapts formal way of atomization. Since previous way of atomization is to put atomizer directly on the water, making the change of atomizer’s distance from water as water evaporates, Exp.1 creates a way called “Floating”. In Floating, atomizer is suspended in a float; constantly keeps the bottom of atomizer from same distance from surface of water. Thus, no matter how much volume of water is evaporated, the best depth of water for atomization and also, the best atomized condition, could stay. Exp2 inquires in relation between atomization and temperature decrease. In Exp2, the atomized volume is fixed, while wind speed and air-contact area are mastered elements. By the theory that, “the wider contact area is, the more efficiently water evaporates,” we could manage out the best condition in temperature decrease. In that way, with the theory practiced, this research, considering environmental case, is supposed to be applied to open-air area one day.
The Titanium Dioxide Toilet Disinfectant
This project aims to improve the quality of toilet hygiene. The product designed should fulfill the requirements of being an environmentally friendly, user friendly and economical toilet seat system which guarantees the safety and hygiene of the toilet. This project also aims to discover the efficiency of the toilet seat system in eliminating pathogens through conducting various experiments.\r In this project, the photocatalytic property of titanium dioxide is applied. When titanium dioxide is under exposure to ultraviolet radiation, they generate free radicals, which are efficient oxidizers of organic substances. Also, research has shown that the safest ultraviolet light used will be UVA. Thus, by using titanium dioxide paint under exposure to ultraviolet light to oxidize pathogens and toxins, the aims will be achieved. Other than that, experiments will be conducted to explore the efficiency of titanium dioxide under exposure to UV radiation in eliminating pathogens by counting the number of bacteria on the toilet seat system after different time intervals the seat system has been turned on.\r The procedure of constructing the product includes drafting the product, purchasing the appropriate apparatus and materials, constructing the prototype, and checking if the product fits the goals set. Lastly, improving the design based on the flaws found during the checking procedure, as well as checking the product to see if it fits the original goals set.\r The procedure of the experiments aimed to explore the efficiency of titanium dioxide under exposure to UV radiation in eliminating pathogens conducted includes\r counting the number of bacteria on the toilet seat system after different time intervals by inoculation of bacteria on the agar plates.\r Test results showed that the number of bacteria had a steady and notable decline after different time intervals. Results also showed that bacteria would be thoroughly terminated after the system had been turned on for at most one hour. The information was then used to set the delay timer to restrict the amount of time the ultraviolet lamp was turned on to save energy.\r Moreover, the toilet seat system has also been improved so that it will complete the automatic cleaning procedure even without the user lowering the toilet seat. This improvement was made so that the product could be more convenient to toilet users.\r The system also deodorizes the toilet as the oxidization of bacteria and organic substances reduces the putrid odor released by them when they carry out chemical reactions.\r In conclusion, the project succeeds in accomplishing the goals set and is capable of improving the quality of toilet hygiene, especially in common households. The project is also successful in finding out that the toilet seat system is efficient in eliminating pathogens.
Wind Power
My school requires year 13 students to complete a year long project of a topic of their choice, culminating in the presentation of a thesis, a display and speech to a public audience. Many different topics appealed, but in the end I decided to build a micro wind-turbine. I have always been fascinated with mechanics, mathematics, engineering, aerodynamics and electricity. A wind turbine is a mixture of these technologies, with the overall goal of electricity production. In a world that is starting to see the true costs of fossil fuels, renewable energy seems to be increasingly popular and the demand for electricity is always growing.\r I was aware that building a wind-turbine from the foundations up wouldn’t be easy. Many of the experts I contacted in the early days cautioned me against trying such a complex thing in one year, at the same time as completing a full Year 13 course. There were, however, people prepared to support me. Michael Lawley, who builds micro wind turbines in New Plymouth was very helpful, just full of priceless knowledge and gave me a few basic parts to start with. The knowledge gained from Doug Clark, who also builds his own 11 kW wind turbines, was such an inspiration. Later I had practical help from Wilson Springford and Darron Matthews.\r I investigated and documented the history of and current state of wind technology, as well as my own experience and learning in the design, construction and testing process. I thought it would be interesting to find out how the electrical and mechanical side works.\r The generator, a washing machine motor, needed to be completely rewired, and converted to DC (direct current) from AC (alternating current). I built my own 3-phase AC to DC converter.\r Other parts like the disc brakes and bearings had to be found. The rest was hand-made and every part, to a certain extent, had to be modified. Probably more than twenty braking system design attempts led to the final decision to incorporate the wind-activated hydraulic disc brake where the wind paddle starts to ease the brake on over a certain wind speed.\r I studied the dynamics of wind turbine blades, their shape, the material they were made from and how this affected their performance. The decision to make my own blades helped me gain a great sense of achievement and knowledge of blade design. I found some New Zealand made 100% recycled plastic pipe, an added bonus because I wanted to have minimal environmental impact. I designed the turbine with three blades to give better starting torque along with a lower top speed, perfect for how I wired the generator.\r I designed the swivel, the part of the wind turbine that enables the power cables to get from the turbine down the tower without twisting up and has the job of carrying the whole turbine, which is mostly made from recycled aluminium. The steel and bearings used to create the swivel were all second-hand parts and materials. The power from the turbine passes through the swivel into the cables and down the tower. The main mast of the tower is a little over 4.7 metres and pivots on two shorter supporting poles which go down around 2.6 metres to the bottom of the reinforced concrete foundation.\r I managed to, design and construct an operational prototype micro wind-turbine, incorporating recycled and recyclable materials as much as possible, with the end result surpassing all expectations.
DNA Detection by EGFET using GaN Nanowires Gate
DNA感測器近年來蓬勃發展,應用層面包括基因工程,醫學及藥物的開發等,然而目前較常使用的感測方法,需要繁瑣耗時的標定過程,且所使用的化學藥劑對環境容易造成傷害,鑒於以上方法的不完善處,我們決定設計一套新的感測系統,此研究結合了氮化鎵奈米線(GaN Nanowires)及延伸場效電晶體(EGFET)的優點,成功的發展出創新的DNA感測系統,氮化鎵奈米線的高生物匹配性及高感測面積,能有效提高靈敏度,延伸式場效電晶體的設計,史感測器具由免標定及時感測的特性,且易於組裝及操作,我們將探針DNA(probe DNA)修是在氮化鎵奈米線作為之延伸閘極上,由於DNA在中性水溶液中帶負電,且DNA之間具有強烈的互補特性,因此當目標DNA(target DNA)與探針DNA接合,形成雙股DNA,氮化鎵奈米線(閘極)的表面電位即會有所變化,並造成FET特性的改變,藉由此性質及能成功感測DNA,研究結果顯示,此研究所發展出的DNA感測器,愈有相當高的靈敏度(10-18),相較於其他以FET技術所設計出的DNA感測器,靈敏度提升了三個數量極,此外此感測器亦具有高選擇性,即使單一鹼基對的突變也能成功辨別;-hybridization based detection techniques are widely developed due to their promising applications in genetics, medicine and drug discovery. However, current DNA detection techniques based on labels or reagents are time-consuming, environmentally-harmful and complex to implement. In this study, we have successfully demonstrated a label-free extended-gate-field-effect-transistor (EGFET) sensor utilizing a GaN-nanowires electrode with DNA probes immobilized, capable of specific DNA sequence identification. The principle behind the design is based on the change in surface potential and charge transfer after hybridization. GaN nanowires, being bio-compatible, provide direct transfer path and high surface area, thus offer an unprecedented opportunity of DNA sensing with high sensitivity. In addition, our EGFET design facilitates easy assembly and operation of DNA detection. Comparative studies on complementary and non-complementary DNA were performed to verify the specificity of the sensor. By adapting GaN nanowires structure, the assay time of DNA was shorten to within thirty minutes. Moreover, our sensor displayed an ultra-high sensitivity in the level of attoM: three orders of magnitude higher in resolution than that of other FET-based DNA detection methods.