全國中小學科展

工程學

IF鋼在不同酸液中腐蝕行為之探討

IF鋼在鹽酸溶液中之腐蝕速度隨鹽酸濃度之增加而增加。12M之硝酸溶液對IF鋼具最強腐蝕性,而最低(0.1M)及最高(16M)濃度之硝酸溶液對IF鋼之腐蝕性則相對較弱。硫酸對IF鋼之腐蝕速度則由低濃度至高濃度呈現極大變化,當硫酸濃度由0.1M漸增至3M時腐蝕速度亦隨之增加,爾後腐蝕速率減小,至硫酸濃度由8M時反而呈現極大之重量增加。由於表面腐蝕層不適於XRD分析,故由EDS結合FTIR分析得知H?SO?/8M-24hrs.情況下試片表面之腐蝕層為Fe?O?。由SEM觀察發現腐蝕速率較大之條件,如HCI/12M-1min.及HNO?/12M-1min.處理過後,試片表面甚至出現具晶體對稱性之蝕恐。由本研究之初步成果發現:是溫下可以利用中等濃度(如8M)之硫酸液來處理鋼鐵,使之表面生成一緻密之氧化鐵(Fe?O?),達到防蝕之效果。IF (interstitials free) steel was processed in various aqueous acid solutions to observe the corrosion behavior. The corrosion rate of IF steel in HCI(aq) increases with the concentration of HCI(aq). HNO?(aq) with concentration of 12M was observed to be the most aggressive for IF steel. The corrosion rate of IF steel in H?SO? solution increases from 0.1M to 3M and then decreases gradually with the concentration. A large amount of weight gain even observed when the concentration was 8M. The protective layer produced during H?SO?/8M-24hurs. treatment was analyzed to be Fe?O? by using SEM (Scanning Electron Microscope), EDS (Energy Dispersive Spectroscopy) and FTIR (Fourier Transform infrared). Etch pits with crystallographic symmetry were observed on the specimens treated with conditions HCI/12M-imin. and HNO?/12M-1min. Processing condition H?SO?/8M-24hrs. could be employed in corrosion prevention for IF steel under ambient environment.

導電高分子發光二極體製作及性能研究

高分子發光二極體乃是利用電子和電洞在發光工作層結合而形成激子,激子在形成後隨即以光的形式衰退,而發出光來。一般而言,高分子發光二極體是一種三明治的形式,電子注入層/發光工作層(高分子)/電動注入層,而通常我們會選擇加入電子傳遞層和電動傳遞層,來增加其發光效果。本研究係針對聚苯胺做為電洞傳遞層對發光二極體之影響,分別對有電洞傳遞曾和無電洞傳遞層之發光二極體作導電度測量、循環伏安法、電位-電流測量、亮度-電位測量。發光二極體中所須之高分子層,須利用旋轉塗佈機,將其均勻的披覆在載體上,由於本校並無此儀器,所以將離心機改造成簡易旋轉塗佈機,並觀察其披附之效果。另外,在封裝元件時,係因學校缺乏真空蒸鍍的儀器,所以將利用電鍍法把鋅鍍在ITO玻璃上,或將鋁片和ITO玻璃緊靠在一起,針對此二替代方法,本研究將探討其所製出原件成效。Polymer light emitting diode (PLED) utilizes the energy gap between the layer of electron and electric hole that emits the light due to the decay of solitron. PLED is always in the sandwich from, that means the conducting polymer is contained between metal as an cathode and indium tin oxide as an anode. It is used the addition of another electric transfer layer and electric hole transfer layer to improve the lighting efficiency of PLED. The purposes of this study are to discuss the effect of polyaniline as the electric hole transfer layer. The study methods are conductivity measure, the cyclic voltametry, the luminance-voltage curve. The simplified spin coating machine was designed to coat the polymer onto the ITO. The zinc was electroplated onto the graphite as an cathode.

節能省碳反射─反射式紅外光液晶智能窗之研發

Automated Traffic Light

This Project is inspired by the situation incurred by pedestrians, which for the most part are students who need a crossway in order to obtain public transportation or to get to the school; the difficulties that are faced by the personnel to exit the parking lot as well as the students who have a vehicle and to help those parents who drop and pick up their children at the school. At the same time, we would like to reduce the amount of contaminated gas emissions that are emanated into our environment. As consequence of the emission of toxic substances, the air contamination can cause side effects such as the burning of eyes or ears, throat irritation and itching and or respiratory problems. Under determined circumstances, some chemical substances that are found in the contaminated air can produce cancer, congenital malformation, brain damage and disorders to the nervous system, as well as, pulmonary damage and harm to the respiratory tract. For the present investigation it has been suggested as a primary goal: The development of a device, in this case a traffic light, which has the objective to reduce the previously mentioned traffic/security problems that arise upon entering and exiting the institution. The secondary goal is to have a friendly ecological impact within our community. This device was built and tested during a month to obtain figures and demonstrate benefits reported. The device should be low maintenance, it should have a long lifetime and, be simple enough to be operated by those who use it. Among the benefits found, the safety of the students, the prevention of accidents such as: car crashes and run overs, etc. Our studies indicate that per week it is consumed an average of 2,020.16 liters of gasoline, in schedules of 13 hours (from 7:00 AM to 8:00 PM) to lessen this figure would have a good ecological impact since all the hydrocarbon emission are harmful to health.

萬用虎鉗夾具

機械加工過程中往往遇到形狀複雜工件,無法用一般虎鉗夾持進行加工。若需加工複雜工件時,需使用V 形槽、壓枕……等等夾具加以輔助,但有些夾具根本無法夾持。若用特殊夾具需拆除原有之虎鉗,而且還必須校正,工作繁雜又浪費很多時間。 本設計之優點為不需更換虎鉗,直接放在虎鉗鉗口即可夾持不規則的物體,利用正向力的作用夾持而不打滑,輕易達到夾持時之穩定和足夠之夾持力,以達迅速、不需使用特殊夾具、不需再校正、可當平行塊之多功能夾具,使複雜形狀之工件加工簡單化、迅速化之設計。;When handling workpieces in complicated and irregular shape in the mechanical process, users are unable to make it with ordinary vises. V-block and clamping block might help, while some others do not work at all. In such cases, the user has to tear the vise apart and then do some correction, which is complicated and time-wasting. The strength of this design is that there is no need to replace the vise. The user just puts this device on the vise clamp to clamp the irregular object. The vertical clamping force makes the piece at work stable and allows no slipping. With this device, no special fixture or further correction is needed. It can also be used for a parallel block if necessary. In other words, as a fixture of multiple functions, the device makes the processing work simpler and more efficient than ever.

極速火龍-利用軟片顯影法觀測氫爆的火焰傳遞

用塑膠軟管作為氫爆安全反應器,從封閉端點燃氫氧預混氣,管中火焰\r 傳遞快速,肉眼難以觀察,因此研製「氣爆顯影記錄器」來觀測,如下圖,\r 光纖導引偵測點的火光至暗箱,記錄於高速旋轉的軟片,從光電轉速計讀取\r 轉速,軟片沖洗後量測各顯影間距,可得火焰位置與時間的關係圖,量測時\r 間最小刻度可達2. 2 微秒。\r 解讀軟片的顯影,得知氫爆初期,火焰加速傳遞,大部分在25cm 位置\r 左右,火焰的速率出現急速飆升(爆燃轉變為爆震),而且火光亮度也急速升\r 高,有時火焰速率出現飆升過高,再回降趨於穩定?的現象,在50 cm 位置\r 左右,火焰進入等速傳遞階段,此階段有穩定的火焰模型,火焰頂端的亮度\r 最高,往後亮度遞減。

巨型小翼效應—未來長程客機經濟省油妙方

本研究主要是探討翼端小翼對飛機飛行的影響,翼端小翼在現在不少的飛機上都有這種設計,假設小翼可以阻止飛機機翼末端的氣流上旋,進而增加升力與推力,讓飛機能提高飛行時的效率,為了驗證這個假設,因此製作了簡易風洞對小翼的升力與阻力進行定性和定量的探討。升力與阻力的定性定量探討是經由10 組主機翼與五個小翼組合,共有2000 次的測試記錄,再轉化成折線圖予以比較研究,而得到一個穩定性數值結果。這測試實驗的數值結果顯示:小翼可以增加升力,但是也會增加阻力,為了降低阻力,小翼的剖面最好是有弧度。The purpose of this research is to find out the effect resulted from the winglet of the plane to the flight. Many a winglet is nowadays designed for the airplane. Assumes the winglet can stop the air of the tail section of the airplane to revolve up, further increase the force of the raise and the push, and uplift the efficiency of the flight. In order to proof this assumption is correct, so makes an easy air hole to do the research of qualitative and quantitative analysis for the force of the raise and resistance. After about 2000 records tested through the combination of ten sets of the main wing and five tiny wings, and transference of curve diagram , we get a steadily value result. This test result appear the first the winglet can increase the force of the raise, and so do the resistance, and the second to have the force of the resistance decreased, it might be better the section of the winglet is not straight but circular.

熱線式渦流流量計

流量計在實驗室與工業領域裡是重要的儀器,如今已經有數十種依不同物理原理而發展出來的型式,可以配合多變的環境需求與測量條件而使用。然而,各種流量計所適用的範圍備受侷限。本研究主要目的在發展一種熱線式的渦流流量計,供給氣體之流量量測之用。透過自行製作儀器與設備:熱線測速儀(包括探針、探棒及電子處理器)和渦旋產生器(管道中含一三角形截面之鈍體,當流體通過時,在後方尾流產生週期性渦旋逸放)。由於熱線測速儀擁有偵測流體運動時高頻動態變化的能力(約為20000 Hz 以內),因此結合熱線測速儀與渦旋產生器,經適當的設計與調校,可以測得在不同流體流速時渦旋產生器的三角截面鈍體後方渦旋逸放的頻率。由於渦旋產生器的截面面積為固定值,因此可以從而計算出流量與渦旋逸放頻率的關係。經由嚴格的校準與驗證步驟,本研究的結果顯示自製的熱線測速儀擁有極佳的渦旋頻率偵測能力,所量測到的校準曲線顯示渦旋產生器的三角形截面柱所產生的渦旋逸放頻率與流量成線性關係。為了降低誤差,建議在0 ~ 40 CMM 之量測範圍內分成三條方程式來代表不同範圍內的校準曲線,最大誤差僅在5%以下。若需使用在不同的流量範圍時,僅需改變渦流產生器和幾何尺寸,以使渦旋逸放頻率適合於熱線測速儀的動態響應範圍即可。倘若商品化之後,可以實際應用於風扇流量量測、引擎進氣埠流量的測量等等應用。熱線測速儀本身也可作為風速計,適用於各種場合之風速量測。Flow meter is a instrument that is vital to the laboratory as well as the industrial related field. Based on different physical principles, tens of models that work in harmony with the diverse environmental demands and measurement conditions are developed to date. However, the application of varied flow meters is still under severe restriction. The purpose of this study is to develop a hot-wire type of vortex shedding flow meter for the use of flow rate measurement. Through the home-made apparatus and device, the hot-wire anemometer (includes probe, stem and electronic processor) and the vortex generator. (duct that contains triangle’s section of the bluff body. When fluid passes through, the wake behind produces periodical vortex shedding.) The ability of hot-wire anemometer when it detects the fluid moving changes of high-frequent movement is within 2000Hz, after appropriate design and adjustment, the combination of hot-wire anemometer and vortex generator may investigate the frequency of different flow rate that generated from the vortex shedding behind the bluff body of triangle section. The section area of vortex generator is constant value, thus it can calculate the relationship of flow rate and the frequency of vortex shedding. By means of strict calibration and test procedure, the results reveal that home-made hot-wire anemometer has excellent ability to detect the frequency of vortex shedding. The calibration curve indicates a linear relationship between the frequency of vortex shedding and flow rate. In order to reduce inaccuracy, it is suggested to classify three formulas to represent the flow rate that ranges from 0 ~ 40 CMM. The greatest inaccuracy is under 5%. When applied to different flow rate range, it only has to change the size of vortex generator only if the response frequency of hot-wire anemometer suit for the range of frequency of vortex generator. After commercialization, it can be applied to measure the flow rate of fans, flow rate of intake valve of engine, etc. Hot-wire anemometer also served as anemometer, which can be applied to wind velocity measurement in any situation.

The Free-D Elevator System

Miracles in life originate from daily life itself. What can be imagined can really be achieved. Hong Kong, as an international city, is small in area and densely populated. To utilize space, tall buildings inevitably emerge. Taking elevators has therefore become the daily routine of everyone of us. However, problems abound with the present elevator system. You have probably gone through the dreadful episode of waiting long for an elevator to come, and passage being interrupted by unreasonably frequent stops. Besides, it wastes space, since each elevator tube can only accommodate one elevator. This is why our Free-D Elevator System will revolutionize the present one. It consists of a large cylindrical tube, which can be divided into several smaller, imaginary sector-shaped tubes. In each small tube a large number of elevators move vertically by magnetic levitation. The elevators can also rotate from one tube to another, thereby avoiding collision. This innovative design will substantially increase the number of available elevators for given space. Most importantly, it is highly feasible.

Night Vision Goggles

Hadley has create a system that enables you to see in the dark, night?vision goggles. The military version usually retail for thousands of dollars, but Hadley’s solution costs considerably less. And they really work! He has even attached close?fit rubber swimming fittings to the eyepieces to ensure you can’t see a thing without the help of the electronics. The key feature of this project is the way Hadley has used his imagination to access and modify existing technology and explore ways of ‘hacking’ these device to obtain useful component system that he can integrate to make a fully functioning product. In doing this he has encountered many unsuitable combinations, but has persisted to reach an extraordinarily effective endpoint. The whole process, which has taken over a year from initial idea to result is a demonstration of tenacity and ingenuity.