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.
告訴你「拉午耳」 「亨利」的壓力有多大 ─自製簡易的 IC 電路板來討論拉?
This research is aimed to make an in-depth exploration into Raoul’s Law and Henry’s Law by using an accurate but simple vapor pressure gauge. The gauge is constructed from non-complicated electronics components- electronics IC PCB, film resistor, digital multi-meter, and battery. In the first step, we measured the vapor pressure of six kinds of liquids and 3 liquid mixtures- water, ethanol, chloroform, acetone, benzene, toluene, mixture of water and ethanol, mixture of chloroform and acetone, mixture benzene and toluene. From the results of this experiments, the vapor pressures of water and ethanol liquid mixture, and chloroform and acetone liquid mixture were slightly lower than their theoretic values-called negative deviation solution, while the vapor pressure of the benzene and toluene liquid mixture was quite close to its theoretic value-near an ideal solution. In the second step, the individual vapor pressures of water, ethanol, and chloroform were measured at various temperatures; the vapor heat(ΔH) were calculated by using the lausius-Clapeyron equation. In the final step, we used the gauge and other non-commercial instruments to measure the B.O.D. values of water from the Kaohsiung Love River, found the P-T correlation using Gay-Lussac’s Law, and calculated the absolute zero temperature value by extrapolation. 本研究是利用一些簡易的電子元件－電路IC板、電阻膜、數位三用電表和電瓶來組裝一 個準確、簡易的氣壓量測器。我們將此量測器用來深入探討「拉午耳定律」及「亨利定律」 。 首先，我們測量了水、乙醇、氯仿、丙酮、苯、甲苯等六種純液體的蒸氣壓，並測量了(水＋乙醇)、(氯仿＋丙酮)、(苯＋甲苯)等兩成份系溶液的混合蒸氣壓。結果發現(水＋乙醇) 、(氯仿＋丙酮)的混合蒸氣壓都比理論值低了一些，此稱為負偏差溶液；(苯＋甲苯)的混合蒸氣壓與理論值差不多，較接近理想溶液。 接下來，我們還測量了不同溫度下水、酒精及丙酮的蒸氣壓，並利用clausius－clapeyron equation求出液體純質的汽化熱( H Δ )。 最後，我們還搭配了自製的儀器裝置，來測定愛河水質的B.O.D.值(生化需氧量)以及探討氣體的給呂薩克定律(P~T關係)，並利用外差法來推求絕對零度。
都是氣泡惹的禍
當輕敲啤酒杯時，會發覺酒杯發出之聲調隨氣泡漸漸消失而有所改變。為了解氣泡是如何影響頻率，我測試了幾種含氣泡之飲料，以探討當氣泡漸漸消失時，杯子發聲頻率之變化。實驗發現杯子內飲料之氣泡漸漸消失時，裝啤酒與可樂杯子的發聲頻率逐漸增高，然而裝沙士杯子的頻率卻逐漸降低。為解開此相互矛盾的現象，我設計了將液面上之泡沫及液面下之氣泡分開檢驗的實驗。實驗結果發現，液體中氣泡的存在會使杯子發聲頻率變高。而當液體表面受到擾動時，會降低杯子的發聲頻率。若液面上存在泡沫時，杯子的發聲頻率也會變低。這表示裝盛含氣泡飲料杯子音律之變化，須同時考量液內含泡量與液體表面之效應。此結果可以成功的解釋為何啤酒、可樂與沙士於氣泡漸漸消失時，杯子頻率會變高或變低的現象。Tapping the side of a glass of beer as the bubbles escape, one can find that the pitch will change. In order to know how the bubbles would influence the frequency, I survey the pitches of a wine glass with various drinks that would generate bubbles. As bubbles getting away from the glass, my experimental data shows that the frequencies of the tone did get higher when the glass contains beer and coke. However, I surprisingly find a different result when the same glass contains sarsaparilla. Hence I design a series of experiments to understand the possible mechanism. The data suggests that when the drinks contain bubbles in it, the frequencies of the tones will be higher. When the liquid surfaces were disturbed, the frequencies of the tones will become lower. If there were foams above the liquid surfaces, the frequencies of the tones will also be lower. This finding proposes that people needs to consider both the bubble bulk status and surface effects. The consequences of the competitions between these two effects can successfully explain how the tones are changed in the cases of beer or sarsaparilla or coke.