| 摘要: | 奈米碳管是由片狀石墨烯所形成之結構物，它的特殊結構使其具有許多優越之特性，例如體積小、熱穩定性良好、熱傳導性佳、強度高、導電性佳等，因此目前被廣泛地應用於各種領域。此外，奈米碳管因具有高比表面積與微孔體積，吸附反應時間快，所以也是良好的吸附材料。在大量生產製造並廣泛應用於環境相關工作之前，奈米碳管於環境中的分佈、流動、宿命、生物(生態)毒性、甚至對於人類健康的影響等都必須先有更進一步的研究與調查。奈米碳管對於微生物之毒性與碳管在水溶液中之分散性有關，而碳管分散性除受其物化特性及水溶液性質影響外，亦由於其良好的吸附能力，而受表面吸附情形所影響。既有文獻多顯示吸附量增加有助於奈米碳管之分散，但本研究團隊在執行98 與99 年國科會計畫中，進行對奈米碳管對鄰苯二甲酸酯類的吸附機理探討，研究中發現，鄰苯二甲酸酯類的分子大小與吸附量對於氧化前後奈米碳管的懸浮性有著完全相反的影響。因此本計畫擬以既有研究成果為基礎，進一步探討多壁奈米碳管在化學氧化前後以及吸附不同種類之鄰苯二甲酸酯類與腐質酸後，多壁奈米碳管的分散或是凝絮行為，並藉由分析微生物之存活、代謝、以及細胞結構等，探討奈米碳管分散性對微生物之毒性。Carbon nanotubes (CNTs) have broad applications due to their unique properties. CNTs have also been considered as good adsorbent due to its high surface area, large pore volume, and fast adsorption equilibrium time. As there are increasing researches and applications of CNTs, it is important to understand the possible interactions, fate, and transport of CNTs as well as their toxicity or impacts to the environments before mass production and discharge of CNTs to the aqueous environments. Literatures have found that the cytotoxicity of CNTs is related to their dispersivity. The dispersivity or aggregation of CNTs depends on their surface physical and chemical properties, the solution conditions, and moreover, the adsorption behaviors of CNTs. While conducting adsorption of phthalate esters (PAEs) on multi-walled carbon nanotubes (MWCNTs), it has been observed that the size of PAEs molecules have the opposite effects on the dispersivity of MWCNTs before and after chemical oxidation. Thus, it is proposed here to investigate the influences of adsorption of different PAEs on the dispersivity and aggregation of MWCNTs before and after chemical oxidation. The dispersivity and aggregation of MWCNTs will be examined by UV spectrophotometer and particle size analyzer, respectively. Besides surface charge, the knowledge of PAEs and humic acid adsorption on the MWCNTs obtained from current studies will be used to explain the dispersivity and aggregation of MWCNTs. The toxicity of MWCNTs on microorganisms will be studied by investigating (1) viability, (2) metabolic activity, (3) concentration of plasmid DNA and RNA in solution, as well as (4) cell-structure intactness of bacterial cultures. The proposed study will provide: a) fundamental information regarding carbon nanotubes dispersion states, transport, fate, and bioavailability in different environmental systems; b) identify factors controlling these environmental behaviors. 研究期間：10008 ~ 10107 |
