以簡易方法探討奈米銀的化學活性優於非奈米級銀粒子
A novel and simple method was developed to determine the activity of silver in nanometer particles more than in non-nanometer particles. The conductivity of conducting polymer, polyaniline (PANI) doped with different amount of nanometer silver particles was used to evaluated the activity of nanometer silver. In polymerization of polyaniline, hydrogen chloride solution usually used to increase the conductivity of polyaniline. When 1%(w/w) nanometer silver particles doped during the polymerization, the conductivity of polyaniline was down from 2.28 s/cm to 0.65 s/cm, then increased with increasing the amount of nanometer silver doped. The conductivity of polyaniline was changed from 2.28 s/cm to 0.47 s/cm when 3%(w/w) nanometer silver particles doped, but it is increased from 2.28 s/cm to 2.44 s/cm when was doped with 3%(w/w) micrometer silver particles. The conductivity of polyaniline changed due to the formation of silver chloride (AgCl) in doping nanometer silver. Some of the nanometer silver particles were formed to silver ion in hydrogen chloride solution for the high activity property of nanometer silver. This also can be proved from the spectra of XRD and FE-SEM. Therefore; determination the conductivity of conducting polymer by doping nanometer metal particles can be used to determine the activity of the nanometer particles. 本研究為開發一個新穎的檢測奈米金屬粒子化學活性大於非奈米金屬粒子的簡易方法。方法為利用導電高分子聚苯胺,於合成過程中添加不同濃度的奈米銀粒 子,並分別偵測其成品的導電度,藉以評估奈米銀粒子的化學活性。由於聚苯胺在合成過程中通常加入鹽酸以提高其導電度,致活性較大的奈米銀粒子於氧化後,隨即與氯離子形成氯化銀的沉澱,而降低聚苯胺的導電度,如添加1﹪(w/w)奈米銀粒子的,其導電度由2.28 s/cm 降至0.65 s/cm,隨後隨著添加量的增加導電度先降後再稍回升。一般非奈米級銀粒子因氧化電位為負值,即化學活性小,而不易被氧化。由實驗結果,我們發現同樣添加3%(w/w)的奈米級銀粒子或微米級銀粒子,添加奈米級銀粒子的導電度由2.28 下降為0.47,添加微米級銀粒子的導電度卻由2.28 上升為2.44,此乃說明本方法確實足以證明奈米級金屬的化學活性的確遠大於微米級金屬,因相同條件下,微米級銀粒子未如同奈米級銀粒子一樣被氧化成銀離子。即奈米級銀粒子可以輕易的被氧化,而非奈米級銀粒子則不易被氧化。尤其也可由X 光繞射儀分析光譜圖和場發射式掃描電子顯微鏡拍攝圖證明。因此,我們可以採用添加3 %(w/w)奈米級金屬銀粒子及微米級金屬銀粒子於導電高分子的方法,並藉導電度的變化,證明奈米金屬粒子的高活潑性。
以簡易方法探討奈米銀的化學活性優於非奈米級銀粒子
A novel and simple method was developed to determine the activity of silver in nanometer particles more than in non-nanometer particles. The conductivity of conducting polymer, polyaniline (PANI) doped with different amount of nanometer silver particles was used to evaluated the activity of nanometer silver. In polymerization of polyaniline, hydrogen chloride solution usually used to increase the conductivity of polyaniline. When 1%(w/w) nanometer silver particles doped during the polymerization, the conductivity of polyaniline was down from 2.28 s/cm to 0.65 s/cm, then increased with increasing the amount of nanometer silver doped. The conductivity of polyaniline was changed from 2.28 s/cm to 0.47 s/cm when 3%(w/w) nanometer silver particles doped, but it is increased from 2.28 s/cm to 2.44 s/cm when was doped with 3%(w/w) micrometer silver particles. The conductivity of polyaniline changed due to the formation of silver chloride (AgCl) in doping nanometer silver. Some of the nanometer silver particles were formed to silver ion in hydrogen chloride solution for the high activity property of nanometer silver. This also can be proved from the spectra of XRD and FE-SEM. Therefore; determination the conductivity of conducting polymer by doping nanometer metal particles can be used to determine the activity of the nanometer particles. 本研究為開發一個新穎的檢測奈米金屬粒子化學活性大於非奈米金屬粒子的簡易方法。方法為利用導電高分子聚苯胺,於合成過程中添加不同濃度的奈米銀粒子,並分別偵測其成品的導電度,藉以評估奈米銀粒子的化學活性。由於聚苯胺在合成過程中通常加入鹽酸以提高其導電度,致活性較大的奈米銀粒子於氧化後,隨即與氯離子形成氯化銀的沉澱,而降低聚苯胺的導電度,如添加1﹪(w/w)奈米銀粒子的,其導電度由2.28 s/cm 降至0.65 s/cm,隨後隨著添加量的增加導電度先降後再稍回升。一般非奈米級銀粒子因氧化電位為負值,即化學活性小,而不易被氧化。由實驗結果,我們發現同樣添加3%(w/w)的奈米級銀粒子或微米級銀粒子,添加奈米級銀粒子的導電度由2.28 下降為0.47,添加微米級銀粒子的導電度卻由2.28 上升為2.44,此乃說明本方法確實足以證明奈米級金屬的化學活性的確遠大於微米級金屬,因相同條件下,微米級銀粒子未如同奈米級銀粒子一樣被氧化成銀離子。即奈米級銀粒子可以輕易的被氧化,而非奈米級銀粒子則不易被氧化。尤其也可由X 光繞射儀分析光譜圖和場發射式掃描電子顯微鏡拍攝圖證明。因此,我們可以採用添加3 %(w/w)奈米級金屬銀粒子及微米級金屬銀粒子於導電高分子的方法,並藉導電度的變化,證明奈米金屬粒子的高活潑性。
Study Biological Deoderization using Bacteria in Rumen of Ostrich
Although it is well known that, unlike the feces of a fowl, those of an ostrich\r do not produce foul smell, the impact of different enterobacteria on elimination of malodorous\r substances has not been seriously investigated. I sought to test the hypothesis that ostrich\r enterobacteria (OE) are useful to eliminate hydrogen sulfide (H2S) and ammonia (NH3), two\r important components of foul smell of the feces.
Recycled PET bottles for vacuum packaging
Vacuum packaging is a packaging technique intended to extend the shelf life of food via the removal of air from an enclosed package prior to sealing. This process limits the growth of aerobic bacteria or fungi due to oxygen deprivation. In this work, we present a novel do-it-yourself vacuum packaging device using the exchange of water and air between two bottles to continuously generate a vacuum-suction effect. The sizes of bottle and vacuum bag were investigated for its impact on the vacuum generation in a plastic bag containing smoked fish sausages. Large commercial 3.1-litre PET bottle generated more vacuum than the smaller ones. An equilibrated vacuum pressure of a smaller plastic bag was lower than that of a larger size. With 3.1-litre PET bottles, the vacuum pressure for 3”x5”, 5”x8” and 6”x9” bags was equilibrated at 8, 10, 18 mmHg, respectively. Sausages packaged by our device last for 14 days when they were kept in -20oC refrigerator, which was comparable to those packed by the commercial vacuum packaging system for household use. This project demonstrates an application of simple science in a real life situation as well as a promotion of environmental protection idea as the electricity is not used in the vacuum generation process and the disposed plastic bottles can be reused.