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Determination and removal of sulfonamides and quinolones from environmental water samples using magnetic adsorbents 下载免费PDF全文
Hao Wu Yating Shi Xiaozhen Guo Shuangli Zhao Juanli Du Hongping Jia Lina He Liming Du 《Journal of separation science》2016,39(22):4398-4407
In this study, the magnetic materials known as polymerized ionic liquid@3‐(trimethoxysilyl)propyl methacrylate@Fe3O4 nanoparticles were synthesized and utilized as potential adsorbents. First, these nanoparticles were applied to the analysis of sulfonamides and quinolones present in different water samples using magnetic solid phase extraction and high‐performance liquid chromatography. Under optimized conditions, the developed method showed excellent detection sensitivity, with limits of detection (S/N = 3) and quantification limits (S/N = 10) within 0.2–1.0 and 0.8–3.4 μg/L, respectively. The spiked recoveries of the SAs and QNs in environmental water samples ranged from 83.5 to 103.0%, with RSDs of less than 4.5%. In addition, the adsorbents effectively removed sulfamethoxazole and ofloxacin present in existing aquatic environments. The adsorption kinetics and isotherms of sulfamethoxazole and ofloxacin on the magnetic adsorbents were studied to assess removal performance. The results indicate that the adsorption process follows a pseudo‐second‐order mechanism, which reveals that the sorption mechanism is the rate‐limiting step and produces high qmax values (sulfamethoxazole = 70.35 mg/g and ofloxacin = 48.95 mg/g), thus demonstrating the enormous adsorption capacity of these magnetic adsorbents. 相似文献
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采用简便的化学腐蚀法在45℃下制备了橘红色荧光多孔硅(PS),通过扫描电镜(SEM)、红外光谱(FT-IR)和比表面积(BET)对PS的结构进行了表征。研究发现,Ag~+能在PS上发生氧化沉积而猝灭荧光。基于此,建立了一种快速、灵敏检测Ag~+的新方法。在优化实验条件下,Ag~+浓度与PS的荧光强度在4.5×10~(-8)~6.6×10~(-7)mol/L范围内呈良好的线性关系,检测限为2.2×10~(-8)mol/L,线性相关系数为0.991 4。该方法用于水样中Ag~的检测,结果满意。 相似文献
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HPLC-atmospheric pressure chemical ionization MS (HPLC-APCI-MS) was used to screen and identify glycosides in tobacco leaf. MS/MS and MS3 and photodiode array (PDA) detection were also used in the characterization. A total of 12 glycosides were found and four of them were identified based on their abundant [M + H]+ ions, UV spectra, and MS/MS analysis and they are scopolin, rutin, quercetin-3-glycoside, and kaempferol-3-rutinoside. Analytical characteristics of the method were investigated. The contents of these glycosides were obtained and compared based on the relative peak area to the internal standard in seven kinds of tobacco leaf. 相似文献
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Zhang Y Liu C Shi W Wang Z Dai L Zhang X 《Langmuir : the ACS journal of surfaces and colloids》2007,23(15):7911-7915
Pyrene derivatives can absorb onto the surface of carbon nanotubes and graphite particles through pi-pi interactions to functionalize these inorganic building blocks with organic surface moieties. Using single molecule force spectroscopy, we have demonstrated the first direct measurement of the interaction between pyrene and a graphite surface. In particular, we have connected a pyrene molecule onto an AFM tip via a flexible poly(ethylene glycol) (PEG) chain to ensure the formation of a molecular bridge. The pi-pi interaction between pyrene and graphite is thus indicated to be approximately 55 pN with no hysteresis between the desorption and adhesion forces. 相似文献
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