奈米複合材料與空氣分子的愛恨情仇-探討奈米碳管對空氣滲透率之影響
本實驗使用聚醚亞醯胺溶液製備基本薄膜,由於玻璃態高分子薄膜過於緻密,一直是高分子薄膜在應用上的一大限制,為了在薄膜上製造缺陷,又不會使薄膜之選擇性降低,因此選擇將酸化之奈米碳管(孔徑10~20nm) 加至聚醚亞醯胺薄膜中。本實驗主要為探討添加不同濃度的酸化奈米碳管對聚醚亞醯胺薄膜的滲透率與選擇率的影響,藉由添加0.5 wt%、1 wt%、1.5 wt%、3 wt%、4 wt%等不同濃度的酸化奈米碳管至15 wt% 的聚醚亞醯胺溶液中,並製作薄膜,測試其基本性質與五種氣體(H2、CO2、O2、N2、CH4)的滲透率及不同空氣分子之間的選擇率。我們總共測試了三種薄膜的性質,分別是表面特性、熱穩定性及結晶型與層間距,薄膜的表面性質,能觀察到奈米碳管在薄膜中製造奈米孔隙結構,增加氣體滲透的孔道,能有效增加氣體的滲透率。增加奈米碳管的量,能有效升高第一階段熱裂解的溫度,雖然熱裂解在本實驗中沒有很大的差異,但是還是可以從熱重分析圖中推測不同量的奈米碳管會影響熱穩定性。在X 光繞射實驗中,添加奈米碳管的薄膜與純聚醚亞醯胺薄膜,在結晶相上都屬非結晶型薄膜,添加了奈米碳管的高分子複合薄膜的層間距明顯增大。在氣體滲透實驗中,我們比較了不同氣體或濃度不同的奈米複合薄膜的氣體滲透率,在不同氣體時,氣體的滲透率會隨著奈米碳管濃度增加有明顯的提升,五種氣體滲透率大致依照H2>CO2>O2>N2>CH4 這個趨勢增減。奈米碳管對1.5%增加到3%或4%的奈米複合薄膜滲透率的影響卻減小,由此可以推斷奈米碳管對空氣滲透率並非無限制的增加,在1.5%以後就漸漸趨近最大值。H2為14.89barrer,CO2 為9.51barrer,O2為6.34barrer,N2為6.48barrer, CH4 為3.75barrer 。本研究總共比較了三組氣體的選擇率,分別是CO2/CH4,O2/N2,H2/CH4,分離率最高的是H2/CH4 的,兩分子的粒徑大小差對分離率有極大影響,差愈大,其分離率也愈高。奈米碳管的量改變並不會使薄膜的氣體選擇率明顯增加或減少,但是加入太多奈米碳管其選擇率會變低。在五片薄膜中,1.5%的薄膜有最好的選擇率,奈米碳管的添加量超過1.5%選擇率就會開始下降。綜合滲透率及選擇率可以分析出,添加1.5%奈米碳管的高分子奈米複合薄膜有較高的滲透率,又不會降低選擇率,在利用上比其他濃度的奈米複合薄膜在有害氣體過濾及空氣的分離回收方面產生更好的效果。;This experiment uses Polyetherimide polymers solution to make basic membranes. Because glassy polymer membranes are too dense for gas permeations, it is one of the limitations in their applications. To increase gas permeability and maintain air selectivity, I made some nanogaps on the surface of the membranes by an acidification multi-wall carbon nanotubes (MWNTs, kinetic diameter 10~20nm) in the PEI membranes. We mainly want to find if it has some influence between the consistency of acidification MWNTs and gas permeability or selectivity. We mixed 0.5wt% 、1wt%、1.5wt%、3wt%、4wt% acidification Carbon nanotube in 15wt% PEI solution, made membranes and tested the character, five kinds of gas permeability (H2、CO2、O2、N2、CH4) and the selectivity between different gases. We have tested the three nature of membranes, including surface characteristic, TGA and XRD. We can see some nanogapes made by carbon nanotube in the membranes. It could availably increase gas permeability. Mixing more carbon nanotube in the membranes could increase the temperature of the first heat-decomposition. Though the heat-decomposition in this experiment didn’t change a lot, we could say that different percent nanotube would affect the membranes’ heat-decomposition. By the experiment of XRD, the membranes with carbon nanotube and the pure PEI membranes attach to amorphous membranes. Nanocomposite’s de-spacing is bigger than pure membranes. In the experiment of air permeability, we compared different kinds of gas or different percent carbon nanotube of nanocomposite if they have some change of permeability. The conclusion is that air permeability increase as the quantity of nanotube increase. The five kinds of permeability the direction:H2>CO2>O2>N2>CH4.The influence of permeability will decrease when the quantity of carbon nanotube increase from 1.5% to 3% or 4%. We can get the conclusion that the increment of gas permeability isn’t limitary. It drifts towards maximal about 1.5%. H2 is 14.89barrer. CO2 is 9.51barrer. O2 is 6.34barrer. N2 is 6.48barrer. CH4 is 3.75 barrer.This experiment totally compared three groups of air selectivity. They ’re CO2/CH4, O2/N2 and H2/CH4. The maximum of selectivity is H2/CH4. The difference of kinetic diameter affects air selectivity a lot. The quantity of nanotube doesn’t associate with the air selectivity, but mixing too much nanotube will decrease air selectivity. The 1.5% nanocomposite has the highest selectivity. If the consistency of the membranes is higher than 1.5%, the air selectivity will decrease. Depend on the gas permeability and the air selectivity, the 1.5% nanocomposite has higher permeability and constant air selectivity. That shows the 1.5% nanocomposite has a better effect on air selectivity and recycling.
線鋁之情-以陽極氧化鋁模板製作氧化亞銅奈米線
我們使用陽極氧化鋁(AAO)模板來製備銅及其氧化物的奈米線。以硫酸銅和乳酸配製電鍍液,利用氫氧化鈉水溶液(NaOH)將其pH 值調整到12,供以不同電壓,可電鍍出銅及氧化亞銅奈米線。在較高電壓下可製備出銅奈米線,而在較低電壓下可製成氧化亞銅奈米線,若使用中間電壓則能製得銅及氧化亞銅的混合態。利用x 光繞射分析儀(XRD)來分析其結晶構造、使用場發射掃描式電子顯微鏡(SEM)以得知其表面形貌。電鍍出的奈米線直徑約60 nm。奈米線的長度可藉由調整電鍍時間或電壓來控制。在製作IC 內部導線方面,銅奈米線深具開發潛能;在提升太陽能電池的轉換效率、製作可見光光觸媒方面,氧化亞銅奈米線極具前瞻性。We electrodeposited copper and cuprous oxide (Cu2O) nanowires with anodic aluminum oxide (AAO) templates. Both Cu and Cu2O nanowires could be prepared with an alkaline cupric lactate solution, which was adjusted to pH 12 using a 6 M NaOH, when supplied with different electrolytic voltages. Cu nanowires could be prepared when a higher voltage was supplied, and Cu2O nanowires could be prepared with a lower voltage. A mixture of Cu and Cu2O nanowires could be prepared with a supply of a voltage in between. X-ray diffraction (XRD) is used to determine the phase composition, and scanning electron microscopy (SEM) is employed to characterize the morphology of the nanowires. The length of nanowires can be controlled by adjusting the time spent on electrodeposition and the voltage supplied. The resultant diameter of the nanowires was about 60 nm. Cu nanowires are promising materials for making the conductive wires in IC, and Cu2O nanowires hold great promise for improving the conversion efficiency of solar cells and manufacturing visible-light photocatalyst.
台灣水生食蟲植物~ 絲葉狸藻捕蟲行為及消化功能的進階探索
The “Insectivorous Plants”﹐ the first historical publication by Charles Darwin﹐contained the detailed observations and meticulous descriptions of various carnivorous plants and had become the most important reference for the study of carnivorous plants﹒ But the prey mechanism and digestive function of the bladder traps of the Utricularia were not well described﹒ The present study has a great success in these fields which include the volume change of bladder traps before and after firing﹐the spontaneous pressure relief of the bladder traps even without being triggered by prey, and the quadriceps visible absorption process﹒ The last two findings are not yet publicated. This laboratory experiment is carried out with Utricularia Gibba﹐a native species of Utricularia in Taiwan﹒ Through static and dynamic observation﹐we find that bladder traps suck in water by 12-25% of body volume change, and the bladder traps release internal pressure spontaneously under long period of waiting, despite not being triggered﹒ We can also easily demonstrate the absorption process of quadriceps by manually triggering the bladder traps to suck food color solutions. All the events above can be clearly seen under microscopy﹒達爾文是最先對食蟲植物作深入且完整研究的科學家,至今他的著作仍是研究食蟲植物的重要資料,但在其內容中對狸藻捕蟲囊捕蟲行為及消化功能的研究觀察並不完整。本實驗使用簡單的方法,在這方面有突破性的進展,包括捕蟲囊捕食前後的體積變化,自發性舒張及囊內腺毛對於食用色素的消化吸收,後兩項發現及實驗均未曾出現在文獻資料中。 本實驗以台灣本土水生食蟲植物絲葉狸藻(Utricularia gibba)為研究對象,由靜態及動態觀察,顯示捕蟲囊捕食前後體積變化為12~25%,且即使在沒有捕到水中生物的情況下,也會有自發性舒張以解除囊內壓力的現象。捕蟲囊內四爪腺毛消化吸收功能的整個過程,可藉由食用色素加以呈現,並清楚的在顯微鏡下觀察到這些現象。
東方帆船推進原理探討
本文研究風洞中之風帆在不同條件下,受風吹拂所產生之升力與阻力關係,並探討及成功 的以數學模型解釋其原因,此研究結果可應用於帆船帆面之設計。其主要探討之變因為以下 之五種: (一) 風速大小對帆船帆面之受力關係:當帆面與風向垂直時,在低風速時,實際測值較接近 風速的一次方的函數關係。高風速時,實際測值接近為風速的二次方的函數關係。 (二) 帆面積大小與受風推進力之關係:當帆面與風向垂直時,在風速固定風速下實驗,得到 面積與風對帆推力成正比。 (三) 順風航行時,帆面之攻角(θ)與受風推進力之關係:航行方向的力與sin 2θ 成正比關係。 (四) 側風航行時,帆面之攻角(θ)與受風推進力之關係:帆面在攻角大於 45°時,航行方向的力與sin θcosθ 有相當程度的吻合,而在攻角0°~45°之間則與飛機攻 角升力資料相接近。 (五) 初步探討雙桅帆與單桅帆面受風推進力之不同:發現其在側風時能有效的減少失速的現 象,在帆面高攻角時,能減少失速現象,依然可以持續穩定的航行,我們也可推想出飛機 的機翼前段的縫翼功能也是如此。 This article is derived from our research of relation between lifting power and its resistant power produced via wind-blow in a wind tunnel under different terms and condition, also to discuss and to explain their causes successfully via mathematics models, thus, the result of this study may be applied in designing of sail-surfaces of sails boats. Its major discussion can be included into the below 5 kinds: - Relation of (1) Relation of sizes of wind-speed against reacceptance of aerodynamic forces over sail-surface: When sail-surface and wind direction becomes horizontal, under low coin-speed, practical measured-value is rather close to wind-speed's linear function relation. When in nigh wind-speed, the practical measured-value is rather close to wind-speed's quadratic function relation. (2) Relation of size of sail-surface and pushing power of wind: When sail-surface and wind direction becomes horizontal, an experiment was made under fixed wind speed, the result obtained is sail-surface size and pushing wind power toward sail is in direct proportion. (3) When it is in “round-the-clock wise” navigation the angle of attack (θ) of sail-surface and the relation with wind's pushing power: Strength of navigation direction and sin2θconforming direct proportion. (4) When it is in side-wind navigation, the angle of attack (θ) and pushing power by wind relation; When the sail surface is in the angle of attack (θ) greater than 45o, the navigation direction power and sinθcosθhas certain extent of conformity, and between angle of attack e 0o-45o, happens to be very appropriate with aircraft's angle of attack and lifting power data. Fundamental discussion of Double Masts Sail boats and Single Mast Sail boats comparing differences of wind-aided pushing power: It was found that stall phenomena could be decreased effectively, when it is side-winded, especially, when the sail-surface is at high angle of attack, it could decrease Stall phenomena, and could maintain stable navigation. We can also assume that the front section of aircraft aide-wing’s function exactly the same.
Geo-engineering CO2 Scrubber
On account of the rapid development of human activities, much more fossil fuel is burnt and thus a greater amount of greenhouse gases are emitted to the atmosphere including carbon dioxide (CO2). CO2, is considered as the major cause of the exacerbating global warming. “Geo-engineering”, literally, means the options that would involve large-scale engineering of our environment in order to combat or counteract the effects of changes in our atmosphere. As a carbon neutral CO2 scrubber is proposed to be a large-scale scheme to fix carbon globally through reducing the CO2 emitted to the atmosphere and our ultimate goal is to implement the CO2 scrubber scheme to the whole globe, that is, a large-scale scheme to our environment, it is a project of geo-engineering. The procedures of the project are as the following: (a)Investigating on the absorption of CO2 produced by calcium carbonate (CaCO3), using different basic substances at different temperatures (b)Investigating the absorption of CO2 in car exhaust produced by combustion of petrol in car engine using basic solid (c)Feasibility of using a prototype of CO2 scrubber in exhaust pipe of car (d)Feasibility of fixing carbon by turning CO2 into dry ice and stored in deep water (e)Feasibility of growing plant in used basic solution Results: 1.The CO2 scrubber prototype had an average CO2 removal ability over 50%, which was considered to be efficient. The concentration of CO2 (561ppm) was even lower than that in the ambient air (CO2 612ppm). During the experiment, the prototype was closely attached to the exhaust pipe and did not fall down. Thus, a CO2 scrubber was feasible to be used in the vehicles. Besides, our prototype was more energy efficient than LM2500 PE simple cycle gas turbine (consumed 21MW electricity) though our prototype had a lower CO2 removal efficiency. The cost of our prototype would be much lower than membrane technology as the production cost of the membrane was high. 2.Unlike existing CO2 scrubber prototype installed in open area (with electric fan installed), our CO2 scrubbers installed in the chimneys of power stations and exhaust pipes of cars are carbon neutral as exhaust gas has high kinetic energy and would pass into the scrubber. 3.dry ice would not evolve carbon dioxide gas at high water pressure such as at the bottom of the ocean. 4.Plants grew well in alkaline environment, it was feasible to grow plants in basic solution. Conclusion: CO2 scrubber is a suitable choice in combating the climate change through absorbing the excess carbon dioxide, with the utilization of the carbonates produced in the reaction, it is hoped that the climate change can be relieved using an environmentally-friendly device.