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1.
研究了新显色剂2-(5-羧基-1,3,4-三氮唑偶氮)-5-二乙氨基酚与钴的显色反应,试剂与钴在pH 6.0~8.0范围内形成稳定的紫红色络合物,其组成比为1:3,λ_(max)=540nm,络合物表观摩尔吸光系数为5.7×10~4,Co~(2+)在0~0.8mg·L~(-1)范围内符合比耳定律,络合物在强酸溶液中能稳定存在,可消除大量离子的干扰,有良好的选择性,方法可以不经分离直接测定维生素B_(12)和合成工业废水中的微量钴,结果满意。 相似文献
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合成了新试剂2 (2 喹啉偶氮) 1,5 二氨基苯(QADAB),研究了其与钴的显色反应及C18固相萃取小柱对显色络合物的固相萃取,在pH3.5磷酸盐缓冲介质中,CTMAB存在下,QADAB与钴反应生成2∶1稳定络合物,该络合物可用C18固相萃取小柱富集,小柱上富集的络合物用乙醇(内含2%乙酸)洗脱后用光度法测定,λmax=590nm,ε=8.36×104L·mol-1·cm-1。钴含量在0.01~0.80mg·L-1内符合比耳定律,方法用于环境样品中钴含量的测定,结果满意。 相似文献
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本文研究了钴(Ⅲ)-1-(2-吡啶偶氮)-2-萘酚(PAN)络合物的胶束薄层色谱行为,探讨了该络合物的胶束色谱分离机理。以聚酰胺薄片为固定相,6.4%SDS:10%Triton X-100:HAc-NaAc(2.5∶4∶1.5)体系为展开剂,建立了选择性好、灵敏度高的钴的胶束薄层色谱扫描测定法,测定波长为450nm。标准曲线的线性范围为7.5~75纳克/斑点,最小检出量为2.5ng/斑点。方法用于Ni~(2+)、Cu~(2+)等八种金属离子混合液及维生素B~(12)针剂中钴的测定,结果令人满意。 相似文献
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钴-4-(5-氯-2-吡啶偶氮)-1,3-二氨基苯-Triton X-100体系的析相富集及痕量钴的光度测定 总被引:2,自引:0,他引:2
本文研究了TritonX-100在浊点条件下对钴-4-(5-氯-2-吡啶偶氮)-1,3-二氨基苯(5-Cl-PADAB)络合物的析相条件,在pH4.0~6.0介质中,将胶束溶液加热到92±1℃,保持40min,络合物即被TritonX-100相富集。富集液在575nm测定吸光度,钴含量在0~4μg/5ml范围内服从比尔定律,干扰离子可在TritonX-100析相液中加入H_2SO_4消除。拟定的方法灵敏、简捷,已用于不经分离直接测定人发及自来水中痕量钴。 相似文献
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甲氧基苯并噻唑偶氮-8-羟基喹啉-5-磺酸的合成及与钴的显色反应研究 总被引:1,自引:0,他引:1
合成了新显色试剂7-[6-甲氧基-(2-苯并噻唑偶氮)]-8-羟基喹啉-5-磺酸.该试剂在弱酸性(pH5.0)条件下,在有非离子表面活性剂存在时,与钴形成紫红色的络合物.其最大吸收波长λ_(max)=560nm,表观摩尔吸光系数为6.17×10~4L·mol~(-1)·cm~(-1).钴含量在0~8μg/10ml范围内服从比耳定律.应用拟定的方法测定了维生素B~(12)等试样中的钴,结果满意. 相似文献
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研究了Co(Ⅱ)-4-(2-吡啶偶氮)间苯二酚(PAR)-聚乙二醇(PEG)-(NH4)2SO4体系的萃取行为及最佳分相条件,建立了测定生物样品中微量钴的非有机溶剂萃取光度法。结果表明,在pH 8.6的六次甲基四胺缓冲溶液中,在(NH4)2SO4存在下,Co(Ⅱ)-PAR的络合物可被PEG相富集萃取。在PEG相中络合物的最大吸收波长为519 nm,表观摩尔吸光系数4.68×104L.mol-1.cm-1,钴量在0~1.8μg/mL范围内服从比尔定律。方法已用于粮食、茶叶等生物样品中痕量钴的测定,回收率97.2%~103%。 相似文献
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2-(2-喹啉偶氮)-5-二乙氨基苯胺光度法测定钴 总被引:12,自引:0,他引:12
合成了新试剂 2 (2 喹啉偶氮 ) 5 二乙氨基苯胺 (QADEAA) ,并研究了其与钴的显色反应 ,在pH为5 .5的磷酸盐缓冲介质中 ,在CTMAB存在下 ,QADEAA与钴反应生成 2∶1稳定络合物 ;用磷酸酸化后 ,在酸介质中 ,体系λmax=6 2 5nm ,ε =1 .4 6× 1 0 5L·mol-1 ·cm-1 。钴含量在 0 .0 1~ 0 .30mg/L内符合比尔定律。方法用于大米、猪肝及水样中钴含量的测定 ,结果令人满意 相似文献
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It is known that Raman scattering signals are one of main interference sources leading up to determination errors in spectrofluorometry, and thus the signals can be easily detected with a common spectrofluorometer. In this contribution, we propose a quantitative method based on the inner filter effect (IFE) of reagents on the Raman scattering signals of solvent by taking the complexation of divalent cobalt ion with 4-[(5-chloro-2-pyridyl)azo]-1,3-diaminobenzene (5-Cl-PADAB) as a model system. By adjusting the excitation wavelength of the spectrofluorometer, we could easily detect the Raman scattering signals of water at 424 nm where the maximum absorption of 5-Cl-PADAB reagent is located. In a solution of 5-Cl-PADAB, the Raman scattering signals of water are decreased owing to the IFE of 5-Cl-PADAB. If Co(II), which could form the binary complex of Co(II)/5-Cl-PADAB and consumes the 5-Cl-PADAB reagent, is present in such a case for a given amount of 5-Cl-PADAB solution, recovered Raman scattering signals could be observed and measured with a spectrofluorometer. It was found that the intensity of the enhanced Raman scattering signals is proportional to the Co(II) concentration over the range from 2.0 × 10−7 mol L−1 to 1.0 × 10−5 mol L−1, and the detection limit could reach 1.2 × 10−7 mol L−1. With that, Co(II) in samples could be detected with R.S.D. values lower than 2.6% and recoveries over the range of 97.2-104.7%. 相似文献
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8-喹啉偶氮显色剂QADCB的合成及其分析性能的研究 总被引:4,自引:0,他引:4
报道了8-喹啉偶氮显色剂2-(8-喹啉偶氮)-5-二羧甲氨基苯甲酸(QADCB)的合成、提纯与鉴定,研究了其与Co(Ⅱ)、Ni(Ⅱ)、Fe(Ⅲ)的显色反应,对QADCB与Co(Ⅱ)的显色反应作了研究。在pH5.9的缓冲体系中,试剂与Co(Ⅱ)形成棕红色配合物,其最大吸收波长位于650nm,表观摩尔吸光系数为4.2×104L.mol-1.cm-1,钴量在0~20μg/25mL范围内符合比耳定律。方法简便、快速,选择性较好,已用于纯铜、维生素B12中微量钴的测定,结果满意。 相似文献
13.
研究了4-(5-氯-2-吡啶)-偶氮-1,3-二氨基苯(5-Cl-PADAB)与Pd的显色反应,在0.48 mol/L H3PO4介质和100℃水浴条件下,5-Cl-PADAB与Pd(Ⅱ)反应生成2:1稳定络合物,其最大吸收波长为570nm,表观摩尔吸光系数为6.39×104 L.mol-1.cm-1。结果表明:Pd含量在0~1.2 mg/L内符合比尔定律,方法已用于矿样中微量Pd的测定,结果与AAS法相符。样品分析结果的相对标准偏差小于4%,加标回收率为98.5%~103.0%。 相似文献
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在两性表面活性剂存在下,5-Cl-PADAB分光光度测定铝合金中的镍 总被引:2,自引:0,他引:2
用5-Cl-PADAB作为测定钴、钯的灵敏试剂已有报导,作者曾用5-Cl-PADAB在表面活性剂存在下,对Ag+的协同增色作用作了研究,并用以测定微量银,获得良好结果。本文研究了在阴、非离子两性表面活性剂AES(烷基聚乙二醇醚硫酸酿)存在下,利用镍与5-Cl-PADAB生成红紫色络合物的吸收光谱,拟定出直接光度测定镍的方法。该体系具有显色速度快,络合物稳定性好,灵敏度较高(ε537=8.1×104),操作简便等优点。用NaF-酒石酸钾钠-硫脲作掩蔽剂,该法用于直接测定铝合金中的微量镍,结果颇为满意。 相似文献
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Z. G. Rezinskikh P. A. Slepukhin I. G. Pervova G. N. Lipunova T. I. Maslakova I. N. Lipunov G. I. Sigeikin 《Russian Journal of Inorganic Chemistry》2009,54(3):396-402
New mono- and binuclear cobalt(II) complexes based on 1-aryl-3-aryl(alkyl)-5-(benzothiazol-2-yl)formazans were synthesized. The structure of the synthesized compounds was determined by electronic and IR absorption spectroscopy, mass spectrometry, and X-ray crystallography. 相似文献
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新显色剂2-(2-噻唑偶氮)-5-二乙氨基苯甲酸分光光度法测定微量钴 总被引:4,自引:0,他引:4
近年来,杂环偶氮苯甲酸类显色剂取得了较快的发展。由于氨基取代结构对试剂性能有较大的影响[1],因此本文合成了新显色剂2-(2-噻唑偶氮)-5-二乙氨基苯甲酸,(TAEB)并研究了它与钴的显色反应。 相似文献
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Inasearchfornewsensitiveandselectiveorganicreagents,athoroughstudyofsomeofthequinolylazo,pyridylazocompoundshasbeenreported'-'.Buttriazolylazocompoundshavenotbeenstudied.Inthispapef,2-(l,3,4-triazolylazo)-5-diethyIaminophenol(TZAPN)and2-(5-carboxy-l,3,4-triazoiylazo)-diethyIaminophenoI(CTZAPN)wereprepared,theconditionsofthisreactionwithcobaltwerestudied.Itwasfoundthatthereagentshadhighsensitivityandselectivityinthedeterminationofmicrogramamountsofcobaltundertheconditionsestablished.Thest… 相似文献
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Cobalt-2-(5-bromo-2-pyridylazo)-5-diethylaminophenol (5-Br-PADAP)-tetraphenylborate ion associated complex is quantitatively adsorbed on microcrystalline naphthalene in the pH range 3.5-9.5 from a fairly large volume of the aqueous samples (preconcentration factor ~30). After filtration, the solid mass consisting of the cobalt complex and naphthalene was dissolved with 5 ml of dimethylformamide (DMF) and the metal determined by first-derivative spectrophotometry. The cobalt-5-Br-PADAP complex can alternatively be quantitatively retained on ammonium tetraphenylborate-naphthalene adsorbent filled in a column (preconcentration factor 120) in the same pH range and determined similarly. The detection limit is 30 ppb (signal-to-noise ratio=2) and the calibration curve is linear over 0.3-8.0 mug of cobalt in 5 ml of the final DMF solution. Eight replicate determinations of 1.0 mug of cobalt gave a mean peak height of 0.208 (at 611.5 nm) with a relative standard deviation of 1.2%. The sensitivity of the method is 1.04 (dA/dnm) ml mug(-1) found from the slope of the calibration curve. The interference of a large number of anions and cations on the determination of cobalt has been studied and the optimized conditions developed were utilized for its trace determination in various standard alloys and biological samples. 相似文献
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Inasearchfornewsensitiveandselectiveorganicreagents,athoroughstudyofslomeofthequinolylazo,pridylazocompoundshasbeenreported.'-'Buttriazolylazoandimidazolylazocompoundshavenotbeenstudied.Inanearliespaper,'wehavereportedthesynthesisandspectrophotometricstudiesof2-(l,3,4-triazolylazo)-5-diethy\phenoland2-(5-carboxy-l,3,4-triazolylazo)phenol.Inthispaper,2-(2imidazolylazo)-5-diethylaminophenol(IZAPN)wasprepared,theconditionsofitsreactionwithcobaltwerestudied.Itwasfoundthatthereagenthadhighsensiti… 相似文献
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《Analytical letters》2012,45(8):1573-1579
Abstract 5-(p-Methoxyphenylazo)-8-(p-tolylsulfonamido) quinoline(MTAQ) has been synthesized. The product was checked by IR, theroograviae-try, NMR and elemental analysis. A highly sensitive spectrofluorim-etric method has been developed for the determination of cobalt(II) based on the formation of a complex with MTAQ in slightly basic medium aqueous solution and In the presence of nonionic surfactant, tween-80. The complex shows two excitation maxima at 304 nm and 338 nm, its emission maximum is centred at 402 nm. The fluorescence intensity is proportional to cobalt(II) concentration in the range of 0-85 ppb. The method has good selectivity and has been applied to the direct fluorimetric determination of trace cobalt(II) in pig's liver, Dianchi shrimp and celery. 相似文献