Highly luminescent N,S- Co-doped carbon dots and their direct use as mercury(II) sensor

Heteroatom doping has been proven as an efficient way to improve the fluorescent efficiency of carbon dots. Co-doping with heteroatoms may introduce more active sites to carbon dots, which would broaden applications of CDs in sensing. In this work, highly luminescent nitrogen and sulfur co-doped carbon dots (NSCDs) were synthesized through a facile one-step microwave assisted method by using citric acid and rubeanic acid as carbon, nitrogen, and sulfur sources. The well-isolated NSCDs not only exhibit an enhanced fluorescent efficiency with a relatively high quantum yield up to 17.6%, but also show potential use as a multi-sensing platform based on their fluorescence “on-off-on” and color changing behaviors. The NSCDs can be directly used for the selective determination of mercury cations without any functionalization. The detection limit is approximately calculated as 0.18 μM and linear range is 0–20 μM. The sensing mechanism is proposed as coordination reaction induced by oligomers upon the carbon core. Furthermore, in the presence of cyanide anions, the fluorescence shows linear recovery associated with the concentration of cyanide, indicating its potential usage for the detection of cyanide ion. The optimized pH range for such fluorescence “on-off-on” sensing system is investigated as pH 6–8, suggesting potential applications in bio-sensing and imaging area. In addition, by adding hydrosulfide anion to NSCDs@Hg²⁺ complex, a notable color change could be clearly observed due to the formation of fuscous HgS. In application, a handy test paper for direct and rapid detection of Hg²⁺ is manufactured for the evaluation of usage of NSCDs in the real circumstance.     

Two-mode Fluorescent Detection of Cyanide by a Simple AIE-based Chemosensor with Red Emission

TPE-TCF, a simple TPE-derivative with red-emission was used to detect cyanide in the condition of single dispersion as well as under aggregate state. It could be found that TPE-TCF exhibited excellent fluorescent response to cyanide in both situations, and the mechanism was supposed to be the reaction between cyanide and the double bond in TPE-TCF as well as the aggregation induced emission property of the reacted TPE-TCF molecules. What's more, TPE-TCF could distinguish cyanide with other species, such as common anions and biotiol well, which indicated it as a potential indicator for cyanide with good selectivity and specificity.     

活性炭处理含氰废水机理研究：吸附和催化氧化机理

通过实验探讨了含氰废水在活性炭表面上的吸附和氧化历程，提出了以化学吸附为特征和在氰化物的氧化过程中铜化合物起催化剂作用的观点．实验研究了金属离子、溶液ｐＨ值及溶解氧对活性炭处理氰化物容量的影响，分别用热力学和动力学实验来计算吸附热和吸附活化能，从而提出吸附机理和催化氧化反应机理．结果指出，氰化物在活性炭上的催化氧化反应与活性炭的表面含氧基因、催化剂Ｃｕ２＋和吸附的溶解氧有关．这一机理对实际处理合氰电镀废水有指导意义．     

分子导线聚合物在氰根阴离子检测中的应用研究

近年来,由于分子导线聚合物(MWP)具有信号放大作用,与其相关的研究备受关注,已被广泛应用于小分子、生物大分子和阴阳离子等的定量检测．其中用于阴离子检测的文献报道较少,主要是通过正负电荷静电作用原理来检测多种阴离子,选择性较差．利用MWP信号放大的优势建立新的传感模式以实现对阴离子的高选择性有效检测是目前MWP研究的难点和热点之一．     

冷原子荧光法间接测定水中氰化物

本文详细研究了氰化物蒸馏条件及其稳定性问题，建立了一个冷原子荧光法间接测定水中氰化物的方法，并用于海水及氰化液中痕量ＣＮ－的测定，结果令人满意。ＣＮ－检出限为０．０２μｇ／ｍＬ，回收率９５％～９８％，变异系数７．３％～８．９％。