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1.
卡尔曼滤波紫外光度法同时测定邻、间、对苯二酚   总被引:3,自引:0,他引:3  
研究了苯二酚三种同分异构体水溶液的紫外吸收光谱,在pH3.6的缓冲溶液中,邻、间、对苯二酚的紫外吸收峰分别为275nm、273nm和288nm,三者重叠严重。选取在240um~290nm范围内,每隔1nm测量一次吸光值共51个点,采用卡尔曼滤波进行处理。可以获得较满意的结果。对10个不同比例组成的标准混合液进行测定,邻、间、对苯二酚三者的平均回收率分别为97.4%,101.7%和98.0%,标准偏差分别为1.72%,3.86%和2.04%。对模拟试样中加入标准的回收率均在96.0%~103.0%之间。  相似文献   

2.
张书胜  梁丽  袁倬斌 《色谱》1999,17(1):52-54
在玻碳纤维微电极上研究了电解液中β-环糊精(CD)的浓度对邻、间、对苯二酚的循环伏安特性的影响,从实验结果和分子结构水平方面考察了β-CD与邻、间、对苯二酚的包结作用。研究结果表明,β-CD与邻、间、对苯二酚的包结作用强弱顺序为间苯二酚、邻苯二酚、对苯二酚。讨论了电泳缓冲液中ΝΗ4Cl,SDS,β-CD的浓度及pH值对邻、间、对苯二酚迁移时间的影响。建立了苯二酚异构体胶束电动毛细管色谱-玻碳微电极柱上安培检测分析方法,方法的回收率在98%~103%之间。  相似文献   

3.
邻、间、对苯二酚磷酰化产物的电喷雾电离质谱研究   总被引:1,自引:0,他引:1  
二乙基亚磷酸酯(DEPH)作为磷酰化试剂,采用Atherton—Todd反应首次对邻、间、对苯二酚分别进行磷酰化,生成相应的磷酸酯;并用电喷雾电离串联质谱(ESI—MS—MS)仪检测产物,首次提出了它们的质谱裂解规律。  相似文献   

4.
苯酚及其光催化降解中间产物的HPLC法同时测定   总被引:7,自引:2,他引:7  
研究了苯酚光催化降解过程中苯酚及3种中间体(对苯二酚、对苯二醌、邻苯二酚)含量的高效液相色谱测定方法,获得了同时测定4种物质的较佳液相色谱条件:流动相V(甲醇):V(水)=30:70,流速为0.8ml/min,进样体积为20uL,检测波长为280nm。用外标法进行了定量,相对标准偏差和回收率分别为0.31%~1.13%和97.2%~101.7%,该法快速、简便、准确,适合于苯酚光催化降解过程中样品  相似文献   

5.
人工神经网络-伏安分析法同时测定邻、间、对二硝基苯   总被引:3,自引:0,他引:3  
将反向传播算法的前馈神经网络用于导数脉冲伏安分析法同时测定邻、间、对二硝基苯。实验在盐酸-氯化钾-乙醇介质中进行,悬汞电极作为工作电极。通过对网络结构和参数的优化,加快了训练速度,提高了预测的准确度。用该法对邻、间、对二硝基苯混合物进行定量分析,预测的相对标准误差(SEP)分别为426%,499%和486%。对人工神经网络(ANN)和偏最小二乘法(PLS)的结果进行的比较表明,ANN法优于PLS法。  相似文献   

6.
反相高效液相色谱法分离和测定硝基苯酚的三种异构体   总被引:3,自引:0,他引:3  
采用反相高效液相色谱法分离和测定了硝基苯酚的三种异构体,其邻、间、对三种硝基苯酚的检出限分别为4.6、6.9和9.3μg/L,相对标准偏差为6.4%、7.1%和4.9%.  相似文献   

7.
分光光度法测定氯化稀土和轻稀土氧化物中的镨,钕,钐   总被引:3,自引:0,他引:3  
本文提出在10%盐酸介质,用紫外-可见分光光度法测定氯化稀土、轻稀土氧化物中的镨、钕、钐,测定波长分别为444nm、575nm、401nm,钐对镨的干扰和镨对钕的干扰均可用校正系数加以消除。方法回收率为97.5%~102.9%,检出下限分别为50×10 ̄(-6)g/mL,10×10 ̄(-6)g/mL,100×10 ̄(-6)g/mL。  相似文献   

8.
庞志功  汪宝琪 《分析化学》1994,22(4):363-365
本文采用同步荧光技术对复方新诺明中有效成份磺胺甲基异恶唑和甲氧苄氨嘧啶进行测定,在△λ分别为72nm和94nm的条件下,测定样品中所含有效成份相当于标示量的95.12%-105.68%;回收率为95.5%-98.1%;线性范围磺胺甲基异恶唑为0.125-4.00μg/ml。甲氧苄氨嘧啶为0.125-3.00μg/ml;相关系数分别为0.9976和0.9968。不经分离和掩蔽直接连续测定,效果良好。  相似文献   

9.
多波长叠加近红外吸收光谱法直接测定酒精饮料中的乙醇   总被引:17,自引:0,他引:17  
利用乙醇在1382nm,1691nm和1730nm处的吸光度值,采用多波长叠加近红外吸收光谱法测定乙醇的含量。结果表明,乙醇在0%~24%(V/V)浓度范围内呈良好的线性关系;回归方程为: A= 0. 01754+ 0. 04747C;相关系数r=0. 9994。用该法可直接测定葡萄酒、啤酒和黄酒中乙醇的含量,6次平行测定的RSD分别为;葡萄酒4.0%,啤酒2.5%,黄酒2.4%。回收率为97.5%~105.0%,本方法具有操作简便,准确和快速等优点。  相似文献   

10.
致癌性多环芳烃萘、蒽、芘的分析方法比较   总被引:4,自引:1,他引:3  
利用薄层色谱(TLC)、紫外光谱(UV)、反相高效液相色谱(RPHPLC)对多环芳烃(PAHs)萘、蒽、芘的分析方法进行了研究。TLC中使用环己烷:氯仿(5:4,V/V)作为展开剂时,三者的R,值分别为0.78、0.65和0.72;用UV法在溶液中测定了三者的最大吸收波长分别为303、380、338nm;当流动相为甲醇:水(9:1,V/V)时三者在RP—HPLC中的保留时间为4.179、5.190、6.178min,5次重复RSD分别为1.1%、1.8%、0.91%,并用于实际水样中萘、蒽、芘的分析。  相似文献   

11.
苯二酚异构体的高效液相色谱化学发光检测法研究   总被引:17,自引:0,他引:17  
高效液相色谱作为一种有效的分离手段已被用于酚类化合物的分析 ,紫外检测法 [1~ 3] 、电化学检测法[3,4 ] 等已用于苯二酚异构体的测定 ,但苯二酚异构体的化学发光检测法尚未见文献报道 .前文 [5] 结果表明 ,苯二酚异构体等对鲁米诺诱导的化学发光具有很强的抑制作用 .基于此 ,本文将高效液相色谱与化学发光技术联用 ,首次建立了苯二酚异构体的高效液相色谱化学发光检测法 .该法灵敏度高 ,选择性好 ,为酚类物质的测定提供了一条新的途径 .1 实验部分1 .1 仪器与试剂  FIA- 2 4 0 0型流动注射分析仪 (中国科学院信通科学仪器公司 ) ;G…  相似文献   

12.
Effects of structural isomerism on solution behaviour of dihydroxybenzenes were examined through the determination of volumetric properties such as apparent molar volumes, apparent molar isentropic compressions, and isobaric expansions. The isomers were 1,2-dihydroxybenzene (catechol), 1,3-dihydroxybenzene (resorcinol), and 1,4-dihydroxybenzene (hydroquinone). The volumetric properties were determined from accurate density and speed of sound measurements at T = (283.15, 293.15, 298.15, 303.15, and 313.15) K and at various concentrations. Values at infinite dilution of these parameters were obtained by suitable extrapolation procedures. The results are discussed in terms of hydrophobic, hydrogen bonding, and dipole–dipole interactions between the three isomers and water. Catechol was found to have the strongest hydrophilic and the weakest hydrophobic interactions with water among the three isomers.  相似文献   

13.
A flow injection system coupled with two simple and sensitive chemiluminescence (CL) methods is described for the determination of some phenolic compounds. The methods are based on the inhibition effects of the investigated phenols on the CL signal intensities of N-chlorosuccinimide-KI-luminol (NCS-KI-luminol) and NCS-luminol systems. The influences of the chemical and hydrodynamic parameters on the decrease in CL signal intensities of NCS-KI-luminol and NCS-luminol systems for hydroquinone, catechol, and resorcinol, serving as the model compounds of analyte, were studied in the flow injection mode of analysis. Under the selected conditions, the proposed CL systems were used for the determination of some phenolic compound and analytical characteristics of the systems including calibration equation, correlation coefficient, linear dynamic range, limit of detection, and sample throughput. The limits of detection for hydroquinone, catechol, and resorcinol were 0.002, 0.01, and 0.3 μM using the NCS-KI-luminol system; for the NCS-luminol system these were 0.01, 0.17, and 1.6 μM, respectively. The relative standard deviation for 10 repeated measurements of 0.04, 0.06, and 1 μM of hydroquinone, catechol, and resorcinol were 1.9, 1.4, and 2.0%, respectively, with the NCS-KI-luminol system; for 0.2, 0.5, and 4 μM of hydroquinone, catechol, and resorcinol these were 2.6, 2.2, and 3.7%, respectively, using the NCS-luminol system. The method was applied to the determination of catechol in known environmental water samples with a relative error of less than 6%. A possible reaction mechanism of the proposed CL system is discussed briefly.   相似文献   

14.
A rapid, simple, and sensitive method for the determination of trace amounts of resorcinol, catechol, and hydroquinone in aqueous media has been proposed. The method is based on their reaction with nitrite. The excess nitrite is then determined by a kinetic method based on its reaction with Neutral Red. The reaction is monitored spectrophotometrically by measuring the decrease in the absorbance at 530 nm by a fixed time method. Resorcinol, catechol, and hydroquinone could be determined by the proposed method in the ranges of 0.1–2.0 mg/mL, 0.25–2.0 mg/mL and 0.1–3.0 mg/mL, respectively. The method was applied to the determination of resorcinol and catechol in pharmaceutical formulations with satisfactory results.  相似文献   

15.
通过在多壁碳纳米管修饰玻碳电极上电聚合亚甲基蓝,制备了聚亚甲基蓝/碳纳米管/玻碳电极(pMB/MWNTs/GC)。用循环伏安法研究了3种苯二酚异构体在该电极上的电化学行为,结果表明,在pH7.0的磷酸盐缓冲溶液中,该修饰电极对苯二酚异构体的氧化表现出优异的电催化性能和选择性,对苯二酚、邻苯二酚和间苯二酚的氧化峰分别为0.104、0.203、0.609 V(vs.SCE),峰电位差值分别为99、406 mV。基于苯二酚异构体在pMB/MWNTs/GC修饰电极上的伏安行为,建立了苯二酚3种异构体同时分析的新方法。考察了各影响因素对测定的影响,最优实验条件下,在5.0×10-6~1.5×10-4mol.L-1范围内,3种苯二酚异构体的阳极峰电流与其浓度存在线性关系,检出限均为1.0×10-6mol.L-1。将该法用于水体及冲洗废液中苯二酚异构体含量的测定,结果满意。  相似文献   

16.
The fluorescent dye Rhodamine B (RhB), in combination with a strong oxidant Ce(IV), was used to investigate the properties of three important polyphenols, resorcinol, catechol, and hydroquinone. The reaction of RhB with Ce(IV) solution in acidic medium was found to elicit strong chemiluminescence (CL). The CL signal remarkably weakened in the presence of resorcinol whereas the two other isomers, catechol, and hydroquinone, hardly had any effect in the same range of concentrations. Based on these observations, a new flow-injection CL method was developed for the determination of resorcinol. In addition, a brief discussion of possible mutual interaction mechanism between the three polyphenols and the components of the system is also presented. The article is published in the original.  相似文献   

17.
A simple reversed-phase LC method capable of detecting ng/ml quantities of phenolic compounds in water is described. Pre-column derivatization with benzoyl chloride is used for the separation and determination o-cresol, m-cresol, p-cresol, phenol, resorcinol, catechol and hydroquinone in water. The benzoyl derivatives formed within in 15 min, were extracted with dietyl ether, and then analyzed by liquid chromatography with UV detection at 232 nm. With a mobile phase of acetonitrile-tetrahydrofuran-water (54:6:40, v/v) the seven derivatives were eluted in 15 min. The detection limits were between 0.05 and 0.50 ng/ml for 50 ml of a standard water sample. The method was applied to the analysis of phenols in wine and river water. The recovery of the derivatives from pure water was 81-94% with relative standard deviations of 2.5-5.0%.  相似文献   

18.
Microchimica Acta - A novel voltammetric assay for the simultaneous determination of hydroquinone (HQ), catechol (CC) and resorcinol (RS) by using an electrochemically treated pencil graphite...  相似文献   

19.
An indirect colorimetric method is presented for detection of trace amounts of hydroquinone (1), catechol (2) and pyrogallol (3). The reduction of AuCl4(-) to Gold nanoparticles (Au-NPs) by these phenolic compounds in the presence of cetyltrimethylammonium chloride (CTAC) produced very intense surface plasmon resonance peak of Au-NPs. The plasmon absorbance of Au-NPs allows the quantitative colorimetric detection of the phenolic compounds. The calibration curves derived from the changes in absorbance at lambda = 568 nm were linear with concentration of hydroquinone, catechol and pyrogallol in the range of 7.0 x 10(-7) to 1.0 x 10(-4)M, 6.0 x 10(-6) to 2.0 x 10(-4)M and 6.0 x 10(-7) to 1.0 x 10(-4)M, respectively. The detection limits were 5.3 x 10(-7), 2.5 x 10(-6) and 3.2 x 10(-7)M for the hydroquinone, catechol and pyrogallol, respectively. The method was applied satisfactorily to the determination of phenolic compounds in water samples and pharmaceutical formulations.  相似文献   

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