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构建了一种基于氯化血红素/金纳米粒子/聚三聚氰胺/多壁碳纳米管复合材料修饰玻碳电极的过氧亚硝酸阴离子电化学传感器,并成功用于过氧亚硝酸阴离子的检测.采用循环伏安法和电流-时间曲线考察了过氧亚硝酸阴离子在传感器上的电化学行为,并对传感器的制备条件及过氧亚硝酸阴离子的检测条件进行了优化.结果表明,碳纳米管滴涂量为5 μL,金沉积时间为20 s,工作电位为0.8V时,所制传感器对过氧亚硝酸阴离子的响应最大.在优化实验条件下,此传感器检测过氧亚硝酸阴离子的线性范围为1.0×10-5~3.5×10-4 mol/L和3.5×10-4~1.1×10-3 mol/L,灵敏度为0.13 A/(mol/L),检出限为1.2×10-7 mol/L(S/N=3). 相似文献
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新催化动力学光度法测定痕量亚硝酸根 总被引:8,自引:0,他引:8
庄会荣 《理化检验(化学分册)》2003,39(8):451-452
在磷酸介质中,痕量亚硝酸根对溴酸钾氧化酰胺黑10B的催化褪色作用,建立了催化动力学光度法测定痕量亚硝酸根的新方法。并探讨了动力学反应条件,方法的线性范围为0.05~1.2μg/10ml,检出限为4.88×10-9·ml-1,用于地面水及雨水中亚硝酸根的测定,结果满意。 相似文献
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本文提出了极谱法测定痕量亚硝酸根的一个新体系。在含有Ni~(2+)和SCN~-的稀硫酸底液中,在单扫示波极谱仪上,有一灵敏的亚硝酸根配合物吸附波,峰电位为-0.57V(vs SCE)。一阶导数峰高与亚硝酸根浓度在2×10~(-8)~2×10~(-6)mol/L之间成线性关系。检测限达8×10~(-9)mol/L。回归方程为:Y=0.47x+0.096,相关系数为0.998,相对标准偏差为1.6%。该法具有良好的选择性,尤其是大量硝酸根不干扰测定。成功地应用于实际样品中痕量亚硝酸根的分析。 相似文献
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流动注射化学发光法测定水样中的痕量亚硝酸根 总被引:11,自引:0,他引:11
亚硝酸根对鲁米诺溴酸钾体系的化学发光具有显著增强作用。据此,结合流动注射技术,建立了一种简单、快速测定NO-2的新方法。方法的线性范围为4.0×10-12~4.0×10-9g/L;检出限为2.0×10-12g/L(3σ);分别对1.0×10-11g/L和4.0×10-10g/L的NO-2进行了平行测定(n=11),其相对标准偏差分别为1.3%与1.5%。用于实验室自来水、饮用纯净水以及雨水中的NO-2的测定,回收率为94%~105%,取得了满意的结果。 相似文献
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H. F. R. Reijnders J. J. van Staden B. Griepink 《Fresenius' Journal of Analytical Chemistry》1979,295(2-3):122-124
Summary Sulphate in various environmental samples was determined by measuring the optical absorbance upon reaction with the barium(II) dimethylsulphonazo(III) complex. The measurement took place in a flow-through system. Interferences from phosphate, metal ions and others were eliminated. The results of a turbidimetric measurement, a spectrophotometric measurement with thorin, an automatic titration and the proposed method are compared. The latter allows the determination of sulphate in the range of 1.4–60 mol·l–1. The standard deviation is 0.3–0.6 mol·l–1, depending on the type of sample (water) analysed. A determination takes 1.5min.
Photometric in einem DurchflußsystemBestimmung von Sulphat mit Dimethylsulfonazo(III) in Umweltmaterial mit Hilfe eines Durchflußsystems
Zusammenfassung Sulfat wurde in verschiedenen Umweltproben durch Messung der Extinktion nach Reaktion mit dem Barium(II)-dimethylsulfonazo(III)-komplex im Durchflußsystem bestimmt. Störungen von Phosphat, Metallionen, u.a. wurden beseitigt. Die Ergebnisse einer turbidimetrischen, einer photometrischen, einer automatischen Titration und der vorgeschlagenen Methode werden verglichen. Die Methode ermöglicht die Sulfatbestimmung im Bereich von 1,4–60 mol·l–1. Die Standardabweichung beträgt 0,3–0,6 mol· l–1 je nach Typ des Probematerials (Wasser). Eine Bestimmung erfordert 1,5min.相似文献
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Ute Hezel 《Angewandte Chemie (International ed. in English)》1973,12(4):298-306
The principal methods for the direct photometric evaluation of thin layer chromatograms are discussed with the aid of examples. Since light is strongly scattered by TLC adsorbents, absorption measurements in reflection are preferable to transmission measurements. In the reflection measurements, an approximation method for the Kubelka-Munk function leads to satisfactory straight calibration lines. The working range for quantitative reflection measurements is in the μg range, and the detection limit is of the order of 10?8g. The standard deviation for spots of equal concentration is less than ±1%. The signal-to-background ratio is improved by simultaneous measurement of reflection and transmission. The measurement of diminution in fluorescence (“fluorescence quenching”) is found to be less sensitive than the reflection at the absorption maximum. However, combined measurement of the reflection and the diminution of fluorescence gives an increase in sensitivity as compared to pure reflection measurements. As in solution photometry, fluorescence measurements are generally much more sensitive than absorption measurements. The working range is normally in the ng region, and the detection limit is around 10?11g. All the investigations described in this paper were carried out on the Zeiss chromatogram spectrophotometer. 相似文献
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指出目前分析化学教科书中关于单色光带宽对Beer定律影响的叙述有误。综述了光度法发展史,说明早在1954年Broderson已经给出了正确的论述。 相似文献
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催化动力学光度法测定痕量苯酚 总被引:5,自引:0,他引:5
研究了在硫酸介质中苯酚对I^-1催化Ce^4+-As(Ⅲ)反应的抑制作用及其动力学条件。建立了用催化动力这光度法测定痕量苯酚的新方法,结果表明,在0.001mol/LCe(SO4)2,0.00125mol/L,As2O3,0.01mg/L,KI,0.0125mol/L,H2SO4和0.13%(w/v)NaCl溶液中测定苯酚,其表面摩尔吸光系数为2.1×10^5L.mol^-1.cm^-1,线性范围 相似文献
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《Analytical letters》2012,45(5):383-392
Abstract Manganese(II) in strongly alkaline medium in presence of triethanolamine (TEA) is readily oxidized to form an emerald green Mn(III)-TEA complex. The complex, long ago proposed by Bruno for a photometric determination, has a molar absorptivity of about one-tenth that of permanganate. However, when measured in a long-path cell this deficiency can readily be compensated for and the enormous advantages over the conventional method result, that chloride is no interference and boiling is not required. In order to employ the simplest available suitable instrument, especially for field work, an LED was used as a light source. Its peak wave length is somewhat off the absorbance maximum and a reinvestigation of linearity and interferences became necessary. Also investigated were some modifications proposed by Nightingale. They were found only to complicate but not to improve Bruno's simple procedure. 相似文献
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