評估不同有機酸用於燃料電池之可行性
本研究主要著重在以三極式電化學測試探討不同有機酸燃料甲酸、草酸、檸檬酸與不同觸媒Pt/C、PtRu/C、PtPd/C 在陽極電極的氧化反應之研究。從CV 圖可得知，分子量較低的甲酸有較低的氧化電位。以CV 與LSV 圖可知，以較高的氧化電流區分，是以PtRu/C 為三種觸媒中最適合當陽極電極的；若以穩定度區分，則以PtPd/C 為最佳。我們挑選PtRu/C 此觸媒進行燃料電池放電性能測試，得到的電流不高，原因在於配置的甲酸溶液為1M，甲酸在PtRu/C 電極反應太快，質傳推動力不足，使得燃料供應不足，造成電位迅速下降。This main target of this study is using three-electrode cells to choose which Formic Acid, Oxalic Acid or Citric Acid and Pt/C, PtRu/C or PtPd/C are better for fuel cell. From CV test, Formic acid which structure is simple has the lowest oxidation potential. Combine CV with LSV, if we focus on current, PtRu/C is the best catalyst for fuel cell. But if we focus on Stability, PtPd/C has the best of them. We choose PtRu/C to do the cell performance test. The current density isn’t enough high, this is because the concentration of formic acid is just 1M. Oxidation reaction of formic acid on PtRu/C is very fast. Mass transfer driving isn’t enough for this high reaction rate, so the potential drop is very fast.
Anaerobic Respiration: A Novel Bioelectrochemical Copper Recovery System?
Increasing concentrations of copper in discharged effluents pose hazards to aquatic food chains. This project aimed to develop a self-sustained copper remediation system based on electrical and microbiological principles. The production of electrons during yeast fermentation was investigated to catalyze the reduction reaction of dissolved copper ions. An electrical circuit was designed to harness electrons produced from either a pure or mixed culture of yeast, and were compared for voltage outputs. This system utilized a combination of carbon cloth and copper wire as the electrodes, and a magnesium sulfate based electrolyte. The better-performing cell was subjected to copper reduction analysis, in which various initial concentrations of copper were examined. Further data analysis was carried out on the voltage outputs achieved with both the mixed and pure cultures of yeast, in which an average base line was established and voltage flunctuations were compared to that of the base line. In this way, it was possible to determine the amount and severity of each voltage flunctuation — thus demonstrating whether mixed or pure cultures of yeast produced more stable outputs. Throughout the experiment, self-constructed equipment, including arduino microcontroller moderated incubators and drip-feed systems were implemented to maintain an optimum yeast growth rate. It was found that mixed yeast cultures produced smoother electrical potential outputs in response to feeding and stress intervals. The copper recovery experiment was therefore conducted using the mixed culture. Through a series of conductivity measurements indicative of copper concentrations, metal recovery was successfully demonstrated. Trend line analysis indicated similar flunctuations between voltage output and copper recovery rates, demonstrating how copper was recovered as a result of electrons harnessed from the yeast culture. These findings can be applied to the development of an energy efficient and cost-effective copper remediation system for contaminated water effluents.
The Actuator
The purpose of the Actuator is to create a practical device that passively exercises\r the lower legs to help prevent blood clots, Deep Vein Thrombosis (DVT), in\r wheelchair-bound individuals of any age. The secondary purpose of the device is to\r improve range of motion of the lower legs and speed the recovery of their leg action. It is hoped that this invention will help to prevent DVT, and allow some people to even use their legs again, through passive or active muscular motion. The invention was produced using a number of prototypes and design sketches. Although the current model is quite functional, as it keeps the users legs in motion, it is still in the prototypic design stage.\r The Actuator is a simple to use, easy to retrofit device. It is also portable and will be\r able to attach onto the front of any wheelchair. It harnesses the motion of the wheelchair to drive the users legs in a circular motion.\r The invention was tested in a closed and controlled environment: the duration of the\r Actuator’s use was constant, a doctor was present to take blood pressure and heart rate, and the rotation speed of the user’s legs was controlled by keeping the wheelchair speed constant. The data was collected by monitoring heart rate and skin surface temperature of healthy individuals, and blood pressure and heart rate of a wheelchair bound individual.\r As seen with both experiments (wheelchair bound, and healthy individuals) heart rate\r increased. In addition, the wheelchair bound individual’s heart rate also noticeably\r increased, with an evident increase in blood pressure as well. However, skin surface\r temperature is sensitive to surroundings and often provides little indication of deep vein blood flow, thus the skin surface temperature measurements were too inaccurate for any conclusions to be formulated.\r The inventor’s grandmother had developed DVT’s in 2005, and passed away because of them. Had she been given an Actuator it may have prevented such a tragedy. Her death was the driving force behind the project’s development. Over the time period that this project has been in process, the true potential of this invention has been realized.\r I truly believe that it will revolutionize the way that we treat people in wheelchairs, and the way people in wheelchairs can treat themselves.
Development of a Method for Measuring the Ozone Concentration in the Atmosphere Using Passive Method
1. Introduction Passive method is widely used for measuring air pollutant for one day to several weeks. This method can be used easily and doesn’t need electricity, but expensive devices are needed for measuring substances, so this is not suitable for high school students for measuring or investigating. Then, we focused on the reaction, in which Indigo, the blue pigment, is discolored by ozone, and we built up a hypothesis, that indigo is suitable for measuring ozone concentration. 2. Experimental Section We soaked a 10 mm×20 mm filter paper in an indigo solution, including hosphoric acid. Then, they were dried in an automatic oven. 5.5 cm×10 cm PTFE sheet was fold in two and five sheets of indigo filters were fixed inside (passive sampler). The passive samplers were fixed on a stand and exposed to ozone in the atmosphere. After a few days, we collected the samplers and put each indigo filter and 4.0 mL of ion-exchange water into sample tubes. Then we shook this and extracted the color pigment. We had the average value of 600 nm from the five sheets as a measure value. 3. Results and Discussion The total amount of ozone for one to seven days measured in the experiment was directly proportional to the amount of ozone measured by Osaka Prefecture. We found that we can measure ozone in atmosphere using our method. Passive method has an advantage: it can be carried out easily. We employed this trait and measured ozone concentration at 23 points simultaneously in the north of Osaka for 48 hours. We made the map of ozone concentration by marking on a blank map. The map we made was just like the map published by Osaka Prefecture. We expect that this method will be useful in measuring ozone, where measuring devices are not available. 4. Conclusion We succeeded developing new method for measuring ozone in the atmosphere by passive method using indigo, the blue pigment.