全國中小學科展

工程學

Titania Nanotubes for Solar Energy and Catalysis

Introduction The discovery of titania (TiO2) nanotubes suggests vast improvements over extant titania properties. Titania nanotubes are aligned in highly-ordered arrays with a large geometric surface area, making them the ideal material for many applications. However, the mechanism responsible for the growth rates of highly-ordered nanotubes with optimal adhesive properties is not fully explained or understood. Purpose of Research The aims of this project were threefold: to explore the effects of different anodizing parameters on the fabrication of titania nanotubes; to study the photocatalytic activity of the nanotubes; and to deposit gold nanoparticles into the nanotubes. Methodology Nanotube Fabrication: Titanium foil was subjected to potentiostatic anodization with the use of various fluorinebased electrolytes, anodization voltage and duration to compare the effects of different parameters. Scanning electron microscopy (SEM) was used to characterize the nanotube diameter and length of the anodized samples. Photo-electrochemica1 Water-splitting: A PEC cell was assembled using the nanotubes as the photoanode and the samples were anodically polarized in a 1M KOH electrolyte. A potentiostat was employed to control the applied bias and to measure the photocurrent response under light irradiation. Overall photoconversion efficiency (ηc) of the samples was then calculated. Catalyst Support: A gold precursor solution was prepared with HAuC14‧3H2O. Using a novel depositionprecipitation (DP) protocol, gold nanoparticles were deposited on the nanotubes. SEM was used to scan for traces of gold and their locations. Energy-Dispersive X-ray (EDX) spectroscopy was used to confirm the identity of the gold nanoparticles. Data and Discussion Nanotube Fabrication: Preliminary studies found the glycerol/water and glycerol/formamide combinations to be the most promising. In glycerol/water-based electrolytes, higher water content corresponded to a decrease in nanotube length while higher anodization voltage resulted in a significant increase in tube diameter and length. In glycerol/formamide-based electrolytes, higher water content corresponded to a decrease in nanotube diameter while higher fluorine concentration resulted in an increase in inter-tubular spacing. The effects of various fabrication parameters were better understood, contributing to greater control over array dimensions. Photo-electrochemical Water-splitting: A higher anodizaion voltage resulted in a significant improvement in photoconversion efficiency. However, this trend was reversed in chlorine-doped samples, where a longer anodization duration corresponded with better photoconversion efficiency. Doping was found to enhance the photoresponse of the samples, with 6.32 % photoconversion efficiency obtained, suggesting new strategies for light harvesting and a step closer towards commercially-viable solar energy. Catalyst Support: Gold nanoparticles (5-10 nm) were successfully deposited onto the titania nanotube samples. Based on current literature, this was the first successful attempt at depositing gold nanoparticles into titania nanotubes. An EDX spectrum confirmed the identity of the gold nanoparticles. Compared to current catalytic converters, the gold/titania nanotube structure offered a larger catalytic surface area for reactants and the ability to function at low temperatures. Conclusion: By understanding the effects of various parameters on titania nanotube fabrication, the anodization process can be optimized to enable more precise control over array dimensions. High photocatalytic efficiency has also been achieved. In addition, doping is found to improve the photoresponse of titania nanotubes. Gold nanoparticles have been deposited, to our knowledge for the first time, onto the surface and inner walls of titania nanotubes.

Door Security

Road Surbace Reflectivity

The focus of this investigation is on how one might be able to reduce the number of accidents and the risk of accidents on our country’s roads by using more reflective products on or in the roads. The reflective products that were used in experimental processes for this investigation were: glass (both brown and clear in colour); oyster shells; reflective paint containing glass beads; glass beads on their own; armour plated glass and a road reflector. These reflective products were compared to a normal tar road and a concrete road

節省能源之社區供水系統

The water-supporting system of community should use high efficiency pumps to\r support water and set up a unique water tower for each floor. Since there are high and\r low period of water-consuming and the variety of water pressure, we have to set up a\r unique water tower for higher floors firstly.\r It help us through high peak period of water-consuming, or it turns on pressure-aid\r pumps to save energy.\r 社區供水系統應採高效率之幫浦高壓供水,分樓層設置專用水塔,在用水有高峰\r 及離峰時段,水壓有高低變化,優先順序供水給較高樓層的專用水塔,樓層專用水\r 塔容量必須足以渡過用水高峰時段之容量,否則就啟動輔助加壓幫浦,達到節約能\r 源之目的。

奈米使你變美了!-奈米二氧化鈦在化妝品上的應用

奈米的科學與技術將是21 世紀所要探討的方向。在了解奈米粒子的表面效應、小尺寸效應、量子尺寸效應、宏觀量子隧道效應後,發現其應用甚廣,諸如再生物、醫學、環境、國防、工業產品等方面,都將佔有很重要的地位。我們主要是利用溶膠-凝膠法來製造二氧化鈦奈米粒子,並了解二氧化鈦奈米粒子可吸收紫外線及光催化反應,將廣泛應用電子、紡織、塑膠、橡膠,空氣淨化及廢水處理方面。本實驗將利用二氧化鈦的吸收紫外線特性,來研究其應用在化妝品上面。The science and technology of nanomater will be the direction we will explore in the 21st century. After understanding surface area effect of nanometer particle, Small size effect, Quantum effect, and Macroscopic quantum tunnel effect, we can diswver the application is very far-fluing. For example:biochemistry, medical science,eneironment,national defense and industrial products,will devine a very important position.We mainly use sol-gel method to produce U-TiO?,and understand the absorption of UV and photocatalysis,plastics,mbber,purging air,and dealing with effluents.This experiment will use characteristic of absorbing UV of U-TiO? for researching the application of cosmstics.

My parking space ,, My Right !!

An Automatic Fine system for the handy-caps parking spaces We human beings Are developing creatures, And we believe that the Importance of scientific innovations depends on how much can they contribute in humanities services. Me and my friend worked so hard to present an Invention or a system that is going to make people lives better. In this point of view that we humans believe in. We work hard and we present Inventions, science fears, and new Ideas by a purpose and an intention that those thoughts, Inventions, Ideas, researches …etc. Will make us better people And will help in building a brighter future for mankind. Invention identity Name of the invention: My parking space,, My Right !! Components: Ultrasonic sensor, color sensor, RFID sensor and reader, buzzer, lights, NXT robot, conductive means (wires) How does the invention work? Operating Process The first point we want to make it clear to you that we have two stages: now (present) and later in real life. For the moment : We are using an educational robot (NXT mindstorm) with a programme from our design , using the Ultrasonic sensor to know if there is a car parking or not then using a color sensor to determine if the car is allowed to park or not And if not then write a ticket and a fine but before that it gives an alarm to notice the driver. The main objective of the invention We want to help maintaining the lost rights for the handy-cap people in their parking spots. Because we gave them less than what the numbers say we should of give them so we didn't give them what they deserve and we came at the same time and steeled it from them. this invention is used: usage fields This invention will be used in the handy-caps parking spaces as well as they will help of the economic. It can be employed and used instead of a lot of security persons or traffic Police department. The future vision of the invention It can be combined in a one small unit and with touch panels to know if there is a car parking or not, RFID to determine if the car is allowed or not to park in this space and a camera to know the exact car or maybe by reading the electronic chip in the cars plate .

Design and Implementation of a Spherical Induction Wheel Motor in Electric Vehicle

本研究提出以「球型感應馬達(Spherical Induction Motor) 」直接作為電動車球型輪胎的想法。四顆球型輪胎以三軸自由度旋轉的方式,將提供電動車更高的靈活性。 本研究聚焦在「球形感應馬達」原型機的開發。透過四個方法:等效電路理論、有限元素分析、實作與實驗,研究了球型感應馬達的四個面向:電機設計、電機實作、電機驅動與電機控制。以電機設計、電機實作證明了構想的可行性,並在建立了球型感應馬達完整的電機機械理論後,進行了電機驅動與電機控制。 最後,本研究實作出一架可運轉的球形感應馬達,並在建立完整的馬達數學模型後,以V/F控制法完成轉速與轉向的開迴路控制。本研究希望這部球型感應馬達,未來將能應用在以球型輪胎為動力裝置的電動載具上。

以彈性體模型評估心血管疾病之新方法初探

我們根據物理學的彈性體振動模型發現:主動脈硬化程度可由測量主動脈相對於心臟運動的延遲時間分析得知。我們除了由樣品之超音波影像分析驗證此一觀念之外,還用一自製模型進行實驗,模擬血管厚度對延遲時間的影響,實驗結果與理論相吻合,證實了彈性體模型之可靠性。在診斷方面,此方法可用目前臨床使用的心臟超音波儀直接進行測量,使得它具有方便、普遍的優點;而且可由體外的胸前超音波掃描(TTE)進行觀測,具有非侵入性、免除受測者的不適及避免副作用,此外,能定量分析、早期診斷、鑑別度高也是此方法重要的優點。According to the elastic oscillation model of physics, we found that the aorta stiffness could be obtained by measuring the delay time of the aorta relative to the cardiac motion. The idea was confirmed by an analysis of the echocardiograph images of several samples. A home-made mechanical model was also employed to simulate the effect of cardiovascular thickness. The experimental results fitted the theory very well, verifying the feasibility of the elastic oscillation model. This measurement could be carried out with the conventional echocardiography instruments, making it convenient and common. Furthermore, the delay time could be measured with TaransThoracic Echo (TTE) instead of TransEsophadeal Echo (TEE). This non-invasion can avoid patients’ discomfort and side effect during medical process. The quantitative measurement also enables that the diagnostics can be progressed in advance.

Shock Induced Battery

a. Purpose of the Research Evidence has shown that people are becoming more aware of environmental protection than in the past. Not only has the government made every effort to implement the policies of environmental protection, but Hong Kong citizens are also more willing to cooperate and help out. However, when it comes to conservation of energy and reduction of wastage, many people still regard it as a burden and they just take it lightly. In fact, environmental protection can be achieved in a convenient and simple way. We can easily put in practice in our daily lives. Because of this, we would like to introduce our invention - “shock Induced battery” by using our knowledge of Physics. b. Procedures The “Shock Induced battery” makes use of locomotion of human bodies to generate electricity. The electrical current generated from the specially designed generator will pass through the diode bridges, which adjust the current to one direction. This enables the electrical energy to be stored in the capacitor. This energy will be released when the battery is correctly connected to a circuit with a switch and a resistor. One of the features of the battery is that it is portable. It is mainly used to charge up electrical devices. But it is hoped that it will replace non-chargeable cells one day, and can directly be used in any electrical devices. In fact, our ultimate goal is to reduce the wastage of materials for making the cells, and to solve the problem of disposal of these cells. c. Data The induced a.c. voltage is full-wave rectified by the diode bridge. d. Conclusions In a word, we are trying to provide a chance for people to put environmental protection in practice, so as to raise the awareness of people about environmental protection. After all, high-tech products only solve the power-saving problem to a certain extent, but it is the awareness and the initiatives of the public which matter. We are convinced that environmental protection brings fun to your daily lives, as you will find practices on environmental protection both convenient and simple.

電離轉輪

This research primarily aims to observe how does the electric work, why does it work and the relationship between the surrounding circumstance and the repulsive torque. The electric whirl is made of an enameled wire bent into right angle with sharpened ends. When an AC high voltage is applied, the electric field intensity around the whirl ends is strong due to the small curvature radius of the ends. The molecules in air at both ends are ionized. This cause the phenomenon of point discharge. The positive and negative ions produced by alternating current forms AC ion wind, and produce a torque to make the whirl rotate. The object of this experiment is to observe the relationship between the surrounding circumstance and the torque repulsion. We design an apparatus to measure the angular velocity of the rotating whirl. We also calculated the kinetic energy of the whirl and the work done by the torque. The repulsive torque can be obtained by Work energy theorem. Result: (1)The angular velocity of the electric whirl is direct ratio to repulsive torque. When we want to find out the relationship between the manipulate reason and the repulsive torque, we can just compare the angular velocity with the manipulate reason. (2)The angular velocity of the electric whirl is only related to the peak voltage, and it does not make difference whether we apply AC high voltage and DC high voltage. (3)When the humidity is over 68%, the electric whirl cannot function normally. (4)Under the low-pressure circumstance, the electric whirl will rotate with glow discharge and the angular velocity will decrease to zero gradually.本實驗是探討電離轉輪的性質、原理與周圍環境的關係。「電離轉輪」為漆包線兩端折成直角並磨尖而成,接上交流高壓電源時,其尖端曲率半徑小,電場強度相對大,會游離尖端附近的空氣分子,產生尖端放電的現象,而交流電交替產生的正、負離子會形成交流離子風,並產生轉動力矩,使轉輪轉動。我們設計一個裝置,使其能偵測轉輪轉動的狀況,運用測得數據計算出轉動時的動能和作功狀況,套用功能定理便可求得轉輪通電時產生的斥力矩。實驗結果顯示(1)轉輪的角速度和尖端斥力矩成正相關,所以當我們想得知尖端斥力矩和實驗操縱變因的關係時,只要比較角速度和操縱變因就可以了,這簡化了原本繁複的計算和冗長的數據處理過程。(2)轉輪的角速度只和峰值電壓有關,和直流或交流沒有直接關係。(3)轉輪在超過溼度68%之後,就不會正常運作。(4)在低壓條件下,轉輪轉動時會伴隨淡紫色的輝光放電(glow discharge)現象,而抽氣塔中與轉輪尖端最接近的一點,也就是電場最強的一點,會和尖端同時產生光芒,相互輝映。