| DC 欄位 |
值 |
語言 |
| DC.contributor | 化學學系 | zh_TW |
| DC.creator | 鄧明凱 | zh_TW |
| DC.creator | Ming-Kai Teng | en_US |
| dc.date.accessioned | 2010-7-30T07:39:07Z | |
| dc.date.available | 2010-7-30T07:39:07Z | |
| dc.date.issued | 2010 | |
| dc.identifier.uri | http://ir.lib.ncu.edu.tw:88/thesis/view_etd.asp?URN=972203054 | |
| dc.contributor.department | 化學學系 | zh_TW |
| DC.description | 國立中央大學 | zh_TW |
| DC.description | National Central University | en_US |
| dc.description.abstract | 中文摘要
全面二維層析(Comprehensive two dimensional chromatography)技術的提出，對於過去分離複雜樣品所產生共析(co-elution)的問題有了新的解決方法，巧妙利用了兩根極性或性質不同的管柱，以正交(orthogonality)形式將分析物在二維平面上展開，比起以往只有一維滯留時間分佈擁有了更佳的解析度與更多的峰容量，大幅改善了對複雜樣品的分析品質。
而目前商業化全面二維層析系統，以冷凍式調制器為主，造價昂貴並且受制於冷劑的補充等問題，因此許多研究致力於閥件式調制器的開發，以簡單、堅固、便宜、無需冷劑等優點而受到重視。而本實驗以自製丁式切換器(Deans’ switch)作為閥件式調制器，並利用自製之前濃縮系統建構出一低成本之全面二維層析方法，應用於大氣中氟氯碳化物(chlorofluorocarbons, CFCs)的量測。以丁式切換器提供快速且連續的樣品脈衝，以60米的DB-1作為第一維管柱，與極短的0.2米PLOT作為第二維管柱，展現揮發度與滯留力之特有正交性結果；最後數據以Surfer 8軟體呈現，在自行撰寫程式碼之運行下，可快速得到2D圖譜、地形圖與積分結果。
在此全面二維層析系統進行檢量線與再現性測詴，針對2D圖譜檢驗層析峰體積對應進樣量的線性關係，線性表現R2值可達0.99以上，RSD值優於4.74%以內(N=4)。並使用傳統一維與全面二維層析法作比較量測空氣中之CFCs，結果顯示CFC-12與CFC-113在大氣中濃度相當恆定，RSD值分別為2.63%(一維CFC-12)、3.34%(一維CFC-113)與3.85%(二維CFC-12)、3.49%(二維CFC-113)，兩方法所得結果相符，更可應證此全面二維層析方法的可靠性。
| zh_TW |
| dc.description.abstract | Abstract
Comprehensive two-dimensional chromatography (GCxGC) opened a new era in improving separation resolution for very complex samples. It uses two columns of different polarity to provide orthogonal separation on a 2-D surface, which considerably increases the peak capacity and hence resolution compared to conventional 1-D chromatography.
A typical commercial GCxGC system often uses a cryogenic modulator whose cost is high, and the consumption of cryogen creates additional financial burden. In contrast, many studies focused on developing valve-based types of modulators, which are simple in design and construction. Moreover, cryogen is not required. In our study we used a Deans’ switch to construct the modulator for GCxGC. When combined with a self-constructed thermal desorption unit, this system was able to analyze atmospheric chlorofluorocarbons (CFCs) at pptv level. The volatile sample peaks eluted from the first column (DB-1 60 m) were sliced into sample pulses by the Deans’ switch and sent to the second column (PLOT 0.2 m) for the second dimensional separation. For optimal GCxGC separation of CFCs the modulation pulse and period were set at 0.2 s and 3 s, respectively.By varying the sample size of a pressurized air sample, the linearity of the method was better than 0.990. The precision at atmospheric concentrations was better than 4.74% (RSD). The Deans’ switch-GCxGC method was further tested by continuous measuring outdoor ambient air, and compared the atmospheric variability of CCl2F2 (CFC-12) and CClF2CCl2F (CFC-113) with that from the corresponding 1D GC results. The variability of CFC-12 and CFC-113 denoted by RSD was 3.85% and 3.49%, respectively, for GCxGC versus 2.63% and 3.34%, respectively, for 1D GC. The comparable results suggest that our Deans’ switch-GCxGC method is sufficiently robust to analyze atmospheric CFCs.
| en_US |
| DC.subject | 全面二維層析 | zh_TW |
| DC.subject | Comprehensive two-dimensional gas chromatography | en_US |
| DC.title | 全面二維層析技術分析空氣中之氟氯碳化物 | zh_TW |
| dc.language.iso | zh-TW | zh-TW |
| DC.title | Comprehensive two-dimensional gas chromatography (GCxGC) for atmospheric chlorofluorocarbons | en_US |
| DC.type | 博碩士論文 | zh_TW |
| DC.type | thesis | en_US |
| DC.publisher | National Central University | en_US |