探討以最經濟的方式偵測低濃度溶液之金屬離子
A novel technology for detection of trace concentration of ions at ppb level was developed. The detection limit of this method can be reached to 1ppb. The Wheatstone bridge usually be used for determination the concentration of metal ion, the major disadvantage of this technique is the precision too low. Atom absorption spectroscopy is better for monitoring trace metal ion, but the cost of instrument is too expensive. In this study, the oscilloscope was used to modify the Wheatstone bridge Circuit. The difference between the voltages of two connection points of Wheatstone bridge was used to estimate the concentration of ions. The amplification system was used in this method to improve the limit to detect ion from 10 ppm to 10ppb. The parameters of measurement including types of probe, match of Wheatstone bridge resistances, parameters of input signal and electrolysis in solution were also being studied. 本研究主要是發展一個富有創新且經濟的ppb ( parts per billion ; 10-9)級,微濃度金屬離子量策技術,目前本實驗設計已可以達到 ppb的偵測極限,尤其本方法不僅能夠應用於定量,尚可做定性偵測。簡易的溶液濃度技術常使用惠司通電橋的方法,但這個方法的缺點在於精確度較低,而另外常用的儀器是原子吸收光譜儀,卻價格高昂。因此,我們回頭對惠司通電橋的技術作改良和創新技術。首先,最重要的新技術是對示波器的改良。示波器被用來量測惠司通電橋的電位,我們比較電橋上兩特定點的電位來判斷濃度,當兩個點的電位相同時代表溶液電阻和控制電阻相同。但當輸入信號的電壓太強時,示波器上並無法判別細微的電位變化,因此造成量測的精度不高。本組設計新的電路用以放大在高強度訊號的波形細微變化,成功將測量極限由 10 ppm推進到 ppb。另外關於此設計中的各種參數,包括探針類型、惠司通電路的電阻匹配、輸入訊號之強度頻率、電極間電容效應及溶液中可能發生的電解效應等,都有精確的探討。最後的設計結果將是創新且有別於以往的設計概念。
長期服用安非他命對小鼠腦部紋狀體內蛋白質表
安非他命的濫用在台灣是非常嚴重的公眾健康及社會問題。安非他命會導致一連串的行為異常,包括在中腦紋狀體內釋放多巴胺及阻止多巴胺回收來增加使用者的活動力。由於安非他命會對腦細胞造成傷害,本研究的目的為探討低劑量、無立即毒性之安非他命(類似於人類使用習慣)長期施打下,是否會對C57BL6 小鼠大腦紋狀體內的蛋白質表現有影響。因此利用西方點墨法分析施打低劑量安非他命(2 到6 mg/kg) 約一星期之後,C57BL6 小鼠的大腦紋狀體中一些重要蛋白質(包括腺.酸受體A2A-R、第五亞型腺.酸環化.AC5、caspase-8 及PARP) 的表現是否有改變。實驗結果顯示,低劑量安非他命處理對這些蛋白質的表現並沒有明顯的差異。但利用二維電泳法可看到有少許蛋白質,在經過安非他命處理下有顯著的差別,如KIAA0193 homolog 、GOS-28、gammacrystallin A、malate dehydrogenase 和phosphoglycerate mutase isozyme B (PGAM-B)。這些蛋白質中,malate dehydrogenase 和PGAM-B 與代謝和產生ATP 有關,但前者是增加的,而後者減少,推測安非他命會影響神經細胞的能量代謝,因此長期施打安非他命對紋狀體造成的影響值得進一步探討。;The wide spreading use of amphetamine (AMPH) in Taiwan has become a serious public health and social problem. AMPH evokes a series of behavior abnormality including enhanced locomotor behavior by releasing dopamine and inhibiting dopamine-uptake in the striatum. Since AMPH is known to cause brain damage, the purpose of this study is to investigate the expression of several important proteins in the striatum of C57BL6 mice after chronic treatment with low and non-toxic dosages of AMPH (mimicking the common usage pattern of AMPH addict). C57BL6 mice were daily IP-injected with various dosages of AMPH (0 to 6 mg/kg) for one week. Expression levels of A2A adenosine receptor (A2A-R), adenylyl cyclase type V (AC5), caspase-8 and PARP in the striatum were analyzed by Western blotting analysis. Most proteins examined were not affected by this 1-week AMPH treatment. By the aid of two-dimensional gel electrophoresis, expressions of a few striatal proteins (such as KIAA0193 homolog, GOS-28, gammacrystallin A, malate dehydrogenase and phosphoglycerate mutase isozyme B (PGAM-B) in AMPH-treated mice were altered. Note that malate dehydrogenase and PGAM-B are two enzymes involved in energy metabolism and ATP generation. Interestingly, the former was increased and while the latter was decreased in AMPH-treated mice. Collectively AMPH may affect the energy metabolism in neuronal cells. These results suggest that the injury induced by long-term AMPH exposure warrants our further concerns and investigation.
金屬的盔甲
Our aim to attend this science fair is to design an instrument that can plat and measure the mass at the same time. In hope of designing a simple, accurate and convenient apparatus, we created an electronic circuit to display our original idea. In the process of constant improvements, we finally accomplished a “Super Mass Plating Gauge”, which can be easily and widely utilized in school teaching. The production of microbalance and the arrangement of electric circuit are the most significant parts in our research. The major components of the “Super Mass Plating Gauge” include a straw, metal clips and our creativity—the well-arranged electric circuit. The idea of microbalance originated from the Internet, but we advanced it by numerous experiments. First, we attached a steel cord to one side of the cathode in the electricity supplier. Next, we fixed the other side to the negative plate. And then, on the end of the negative plate, we tied a metal clip with the metal that will be plated. Eventually a new “plating gauge” was invented. By doing so, we could use this instrument to make our experiments. Our experimental goal is to research how different kinds of metal, time, electrode and voltage can affect the reduced mass on the cathode. We made use of such metal as copper, zinc and silver to carry out the experiments. In the end, by analyzing the results, we concluded a plating formula that can be applied to metal plating.
我們做此科展的目的,是要設計一個可以邊電鍍、邊測量質量的儀器,我們希望這個儀器是簡便、精確、且線路簡單,並且能推廣到教學的器材。經過我們不斷改良,終於完成了「便利質量電鍍器」 。 其中製作微量天秤和線路的配置方法,是本研究的重要部分。微量天秤的主要結構是吸管、鱷魚夾、及線路。微量天秤的構想,是參考以前的科展作品並加以改良,可精準測量到0.00010g,而裡面的線路,則是我們的創意(如圖一) 。只要把電源供應器的正極,接上左右任一鋼條,負極接到容器另一端,並加上一個鱷魚夾,夾上被鍍物,便是一個可邊電鍍,邊測量質量的儀器了!如此一來,我們就能以此儀器來作我們以下的實驗。 我們實驗目的在探討電鍍時不同金屬、不同時間、電極大小及電壓,對正極金屬片所減少質量的影響。 最後,我們推導出一個有關電鍍時正極金屬片質量變化量的實驗公式。為此,我們也要做許多次、許多種的實驗,來驗證我們的公式是否正確,並以我們所學的理論來推論。
毛細管內液體流速之探討及黏度測量方法之創新
有一次上實驗課時看到鄰桌的同學正以實驗室的毛細管吸吮一瓶\r 葡萄汁,每當他吞嚥時,毛細管內殘餘的葡萄汁竟然以近似等速的狀\r 態降回果汁瓶裡,這似乎違背了重力加速度的常理,是毛細管的影響\r 嗎?還是葡萄汁特有的現象?這與毛細管插入葡萄汁的深度有關嗎?\r 這一連串的問題皆因升學壓力而無暇深究。\r 升上高中的那年暑假,我參加了學校舉辦的資優科學營,在物理\r 實驗課中恰好遇到了以毛細管測量液體黏度的實驗,使我有機會深入\r 思索毛細管內液體流速的問題。這個實驗很不好做,要調整兩個定高\r 容器,使水平毛細管兩端產生固定的壓差,讓流經管內的液體為等速\r 的流動。大家手忙腳亂地操作了近三小時,測出來的黏度不僅和老師\r 公布的答案差距甚大,而且各組同學所測得之結果也大相逕庭,不過\r 我們都體驗到了液體黏度對流速的影響。\r 實驗的誤差為什麼那麼大?扣除人為操作誤差後儀器本身還有多\r 大改進空間?有否更精簡的方法測量黏度?毛細管中液體的流速真\r 是固定的嗎?把毛細管斜置或是垂直架置,流速還會固定嗎?重力不\r 會影響流速嗎?若流速真為固定的,如何控制或改變流速呢?是否可\r 以利用流速來測出液體黏度?\r 由於我對這個實驗的專注,在學校選修的專題課程中即以此為題\r 目做長期的研究,在老師的指導下,我和同組同學不停地查閱有關書\r 籍及整理資料,漸漸研究清楚原理後定出實驗計畫,並開始購買材料\r 與工具,長期地動手實驗及改進,兩年來我們利用毛細管中液體的等\r 速及不等速流動的特性,發展出了兩種既精簡又準確的液體黏度測量\r 法,以下就是整個研究及創作的過程。\r \r \r The viscosity is one of the most important parameters of the fluids. In conventional viscosity experiments, capillary-based viscometers are widely adopted because of their user-ready devices and moderate prices. However, to accurately measure the viscosity, the fluid velocity must be kept constant; otherwise, the fluctuation may cause the serious deviation. Besides, traditional capillary viscometers often require a long time to make the measurement. This research aims at exploring the capillary fluid mechanics and developing accurate and rapid methods to measure the viscosity. In this study, we developed two creative viscosity-measuring methods, the gravity sloping helical structure and the gradational liquid-level difference, and constructed two cost-effective capillary viscometer prototypes accordingly. The gravity sloping helical structure employs a long helical capillary as the flow channel and utilizes the gravity force to keep the fluid velocity extremely constant. The highlight of this method is that we can see the fluid flow through the capillary directly. On the other hand, the gradational liquid-level difference method uses the pressure sensors to precisely monitor the liquid-level difference, which drives the flow in the capillary, and allows automatic measurement of viscosity. Compared with computer simulation, the experimental results agreed well with the theoretical values. The gravity sloping helical and gradational liquid-level difference methods achieve 0.5% and 0.8% accuracy respectively. In addition, the automation of viscosity sensing also greatly facilitates the viscosity measurement. Furthermore, these two methods are both valuable for incorporating into educational purpose and industrial application.
奈米防蝕專家-微乳液法製備聚苯胺奈米粒子及其在防蝕應用研究
導電高分子在各面之應用非常廣泛,其中聚苯胺因價格便宜,製作簡便,使\r 其應用潛力更為突出。聚苯胺在鐵系及非鐵系金屬之防蝕能力已被證實,但由於\r 聚苯胺與金屬之附著力不良使其應用受到限制。奈米粒子所具有的表面效應、小\r 尺寸效應及宏觀量子隧道效應,使得奈米微粒材料之應用蓬勃發展。但在高分子\r 奈米微粒之製備仍屬有限。本文以微乳液法製備聚苯胺奈米粒子,以提高聚苯胺\r 與金屬間之附著力,使其防蝕能力充分發揮。國外雖已有廠家製作聚苯胺防蝕塗\r 料,但屬於商業機密無從得知其製備方法。本文所研發的微乳液法則是國內首\r 創!\r The development and application of the conducting polymer polyaniline is\r getting prosperous and popular. The capability of polyaniline in corrosion protection\r has been proved. But due to the adhesion of polyaniline on the metal is poor, the\r applications are restricted. By the way, the nanoparticles have the special effects such\r as the surface effect, the small size effect and the macro-quantum channeling effect\r make its applications are prosperous.\r In this paper, the authors utilized the microemulsion method to produce the\r polyaniline, to modify the adhesion of polyaniline on the metal in order to improve\r the effect of the corrosion protection of polyaniline in ferrous metal. The experimental\r results show that the nano-polyaniline has good adhesion on metal. The metal coated\r a layer of nano-polyaniline has the great ability of anticorrosion under different\r corrosion situations after weeks. The nano-polyaniline produced by the\r microemulsion method add the recipes invented by the authors has great potential to\r use in scale-up production in industry.