排序方式: 共有33条查询结果,搜索用时 15 毫秒
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提出了运用化学发光法测定食品中亚硫酸盐的新方法,对影响化学发光的诸因素进行了实验和探讨,得出较佳检测条件:方法的定量限为4.6 mg/kg,亚硫酸盐质量浓度在1.0~10.0 mg/L与发光强度增强值(△I)呈良好的线性关系,R2为0.993 4.对6类样品进行了测定并做加标回收试验,平均RSD 3.05%,平均回收率93.0%,可用于食品中亚硫酸盐的定量与定性检测. 相似文献
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在酸性条件下,溴酸钾氧化鲁米诺产生化学发光,铬(Ⅵ)对这一体系的化学发光具有增强作用,据此,结合流动注射技术,建立了一种测定铬(Ⅵ)的新方法。考察了流路、流速、鲁米诺浓度、氢氧化钠浓度、溴酸钾浓度和硫酸浓度对发光强度的影响。在优化的实验条件下,铬(Ⅵ)浓度在1.0×10-7~1.0×10-5mol/L范围内与化学发光强度呈线性响应,检出限为2.0×10-8mol/L(3σ),对1.0×10-6mol/L的铬(Ⅵ)进行了平行测定(n=11),其相对标准偏差为3.2%。将此法应用于电镀废水中,回收率为94%~98%。 相似文献
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Judong You 《仪器科学与技术》2013,41(5):524-534
A luminol–carboxymethyl chitosan (CMCS) system was established using flow injection chemiluminescence (CL) based on the enhancing effect of CMCS on the luminol–dissolved oxygen reaction. The CL intensity was linear with the CMCS concentration ranging from 0.01–30.0 µM. Al(III) was shown to quench the CL of the luminol–CMCS reaction, and the decrease of CL intensity was linear with the logarithm of Al(III) concentration over the range from 10–1000 pM with a detection limit of 3.5 pM (3σ). At a flow rate of 2.0 mL min?1, the analysis was performed within 30 s. The proposed CL method was successfully applied to the determination of picomole levels Al(III) in human saliva and urine after oral intake of two aluminum hydroxide tablets, with recoveries from 90.6–108.7% and relative standard deviations <3% (n = 5). The results indicated that the excreted Al(III) in saliva and urine reached its maximum values at 3 hr and 2 hr, and the total excretive ratio were 1.24 × 10?3% and 3.45% in 6 hr and 12 hr, respectively. The elimination rate constant k and the half–life time t 1/2 in human saliva and urine were 0.3747 hr?1, 1.8495 hr, 0.7132 hr?1, and 0.9717 hr, respectively. The possible CL mechanism of the luminol–CMCS–Al(III) reaction is discussed. 相似文献
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Lichuan Niu Zhenghua Song Donghua Chen 《Journal of the science of food and agriculture》2010,90(2):338-342
BACKGROUND: A green, simple and sensitive flow injection chemiluminescence (CL) procedure is proposed for the determination of Sudan dyes. The method is based on the finding that Sudan I, II, III and IV markedly enhance the CL intensity of the luminol/dissolved oxygen reaction. RESULTS: The increment in CL intensity was proportional to the concentration of Sudan I, II, III and IV, giving calibration graphs linear over the ranges 0.007–1, 0.5–30, 1–10 and 0.7–300 ng mL−1 respectively (R2 ≥ 0.9981), with limits of detection of 0.002, 0.2, 0.3 and 0.2 ng mL−1 respectively. At a flow rate of 2 mL min−1, complete determination of Sudan dyes, including sampling and washing, could be accomplished in 40 s, with relative standard deviations of less than 5% (n = 7). CONCLUSION: The proposed method was successfully applied to the determination of Sudan IV in contaminated hot chilli powder, with recoveries ranging from 89.3 to 108.4%. The possible mechanism of enhancement of the lumininol/dissolved oxygen CL reaction by Sudan IV can be attributed to the acceleration of electron transfer. Compared with other procedures, the proposed CL method offers the highest sensitivity and the least reagent consumption for the determination of Sudan IV. Copyright © 2009 Society of Chemical Industry 相似文献
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利用α-酮酸和4,5-二胺基邻苯二酰肼合成了3种新发光试剂(EDIQ、HDIQ和CEDIQ)。详细地研究了过氧化氢浓度、铁氰化钾浓度和氢氧化钠浓度对化学发光强度的影响,并对其化学发光性能进行了研究,结果发现新发光试剂EDIQ、HDIQ和CEDIQ发光强度分别为鲁米诺的0.83、3.51和1.92倍。 相似文献
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J Pettersen 《Journal of the science of food and agriculture》1994,65(3):307-313
Sodium hypochlorite-induced and luminol-sensitised chemiluminescence (CL) of refined, high quality fish oils (FO) have been examined in order to evaluate a sensitive method to determine the flavour quality, ie the rancidity of the oils. Dispensing sodium hypochiorite (NaOCl) into emulsified FO caused a burst of CL and the counts of CL per mg FO increased with the amount of emulsification. The NaOCl induced burst of CL increased with the concentration of NaOCl. CL intensity increased with the temperature and was influenced by O2 in the headspace of the cuvette located in the luminometer. The addition of luminol (Lm) to a concentration of 0.2 μM increased the NaOCl induced CL sevenfold. The deterioration of stored FO samples produced NaOCl induced Lm sensitised CL that increased with storage time and were correlated to the sensory scores. The performance of the CL analysis is simple and rapid (approximately 10 min). The Lm addition improved the sensitivity of NaOCl induced CL and the method is suitable for evaluating the rancidity of refined, high quality fish oils. 相似文献