利用硫醇分子合成金奈米團簇應用於檢測自來水及游泳池水中次氯酸根
隨著大眾對於衛生要求的上升，許多抗菌及消毒成分被廣泛應用於水質處理中，其中次氯酸作為消毒殺菌劑大量使用於泳池及自來水的水質淨化中，然而現行標準方法測定水中有效氯所使用具危害的毒化物且步驟繁雜不利普及民生使用，發展簡便快速且靈敏的偵測方法勢在必行。本研究利用牛血清白蛋白（Bovine serum albumin, BSA）、不同的硫醇分子及金離子合成具螢光特性之硫醇修飾金奈米團簇 （Thiol ligand assists BSA capped gold nanoclusters, BSA/RSH-Au NCs），探討添加不同硫醇分子對所合成之金奈米團簇於不同pH值及常見離子對螢光強度之影響，並利用具有最佳螢光穩定性之2-巰基苯甲酸修飾金奈米團簇（Thiosalicylic acid assists BSA capped gold nanoclusters, BSA/TA-Au NCs），透析後進行次氯酸根檢測，其檢測線性範圍為0.98μM-1000μM，涵蓋法規規定游泳池水及自來水中次氯酸根之容許殘留濃度，最後此方法成功於游泳池水及自來水基質中檢測次氯酸根，分析樣品的回收率介於94.4%-95.6%。此外，在紙上添加金奈米團簇，並加入不同濃度的次氯酸根，觀察其螢光強度的變化，期望此方法未來應用於快篩試紙塗布材料快速檢測水質中次氯酸根濃度。
Absorption of Sr2+ at low concentrations using C.moniliferum-- With the aim of practical use of contaminated water processing of the Fukushima Daiichi Nuclear Power Station
We are conducting research for the purpose of treating contaminated water generated by the nuclear accident with C.moliniferum. In previous research, the school seniors examined whether there is a difference in absorption by changing the wavelength of the LED to establish efficient Sr2+ absorption conditions. As a result, the red wavelength was found to be effective for the efficient Sr2+ absorption of C. moniliferum. Therefore, in this study, in order to verify how much Sr is actually absorbed into the cell, the amount of Sr absorption using an atomic absorption photometer is quantified, and the previous research has shown that red is effective for the efficient Sr2+ absorption. The wavelength was considered to be effective because of photosynthesis, and was observed with a scanning electron microscope (SEM) using the photosynthesis inhibitor (DCMU). As a result, it was clarified that C. moniliferum absorbs Sr intracellularly, and photosynthesis was related to absorption.
The change in NaCl crystals from cubic to octahedral～Sodium polyacrylate stabilizes the {111} face of Miller indices～
When adding 2% or 4% sodium polyacrylate as habit modifier, standard milky-white octahedral NaCl crystals grew gradually in saturated NaCl solution on the bottom of the container. [1] [2] Sodium polyacrylate is well known as a highly water-absorbable polymer with many carboxylate anions. In the case of low concentration (0.01%, 0.02%, 0.05%, 0.1% and 0.5%) sodium polyacrylate many small or microscopic crystals whose shapes were nearly octahedrons and had {111} faces were observed with an optical microscope on the bottoms of the solution containers. In low concentration sodium polyacrylate, octahedral NaCl crystals made up of electrostatically unstable {111} faces grew similarly to crystals in high concentrations of 2% or 4% NaCl. Therefore, by adding sodium polyacrylate to saturated NaCl solution, cleaved rock salt crystals in this sol were observed to find out whether or not a change in crystal morphology from cuboids of {100} faces to octahedrons of {111} faces would occur. Regardless of the sodium polyacrylate concentrations of 0.01%, 0.02%, 0.05%, 0.1%, 0.5% and 2%, all cuboid crystals changed into a pyramidal shape in which four of the side surfaces formed an equilateral triangle. When one side of each equilateral triangle face was rotated so the square face of the crystal was soaked in the NaCl sol, all crystals grew into octahedrons of high transparency. Sodium polyacrylate, even under a low concentration, caused morphological change in the NaCl crystals. Many carboxylate anions in the sodium polyacrylate attracted sodium ions and the repulsive force between the carboxylate anions became weak, excluding the water in the internal space of the polymer. We considered that the stabilizing {111} faces of gathered sodium ions attached to carboxylate anions. Chloride and sodium ions coordinated continuously to minimize the NaCl surface area, growing into an octahedral and lowering the surface energy of the NaCl crystal. [3]