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《Analytical letters》2012,45(14):2487-2498
Abstract A colorimetric method for the determination of certain 8-hydroxyquinolines has been developed. The method is based on the coupling of 8-quinolinols with diazotriazole carboxylic acid in the presence of sodium carbonate (0.5% w/v) at ambient temperature (around 30°C). The resulting azo dyes are stable and give intense absorption in the range of 486–540 nm. Beer's law is valid in the concentration ranges of 1 – 8, 2.5 – 17.5, 5 – 35, 2 – 20, and 2 – 20 mcg/ml for 8-hydroxyquinoline (HQ), 5,7-diiodo-8-hydroxyquinoline (DIQ), 5,7-dibromo-8-hydroxyquinoline (DBQ), 5-chloro-7-iodo-8-hydroxyquinoline (CIQ) and 8-hydroxy-7-iodo-5-quinoline sulfonic acid (SIQ), respectively. The proposed method has been successfully applied for the determination of the studied compounds in pure form and in commercial formulations. The obtained results are in good agreement with those obtained from reported methods. 相似文献
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为优化BiOCl光催化剂的结构,改善其对有机污染物的吸附性能,进而提高光催化反应活性,采用超声辅助化学沉淀法制备了BiOCl/蒙脱土(MMT)复合光催化剂,并考察了MMT质量分数(w(MMT))对复合光催化剂结构及光催化反应活性的影响。 X射线粉末衍射(XRD)、扫描电子显微镜(SEM)、傅里叶红外光谱(FTIR)和紫外-可见漫反射光谱(DRS)等的表征结果表明,所得催化剂呈微球状结构,禁带宽度为3.24 eV。 随着w(MMT)的增加,催化剂的微球状结构逐渐被破坏,但带隙能未发生明显变化。 以8-羟基喹啉为目标物考察了复合催化剂的吸附及光催化反应活性。 结果表明,随着w(MMT)增加,催化剂对8-羟基喹啉的吸附和光催化氧化活性逐渐增加,这可归因于与MMT的复合增大了比表面积并降低了光生载流子复合效率。 当w(MMT)为15%时,催化剂的吸附及光催化性能达到最佳,光照50 min后,8-羟基喹啉的降解率达到85.6%,矿化率达到51.0%。 光生空穴和超氧自由基负离子为主要的氧化活性物种。 复合催化剂还可高效降解邻苯二酚和对氨基苯甲酸。 同时,复合光催化剂表现出较强的化学稳定性,表明其具有较强的实际应用价值,可用于处理含有机酚类污染物的工业废水。 相似文献
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Jacobo Otero-Romaní Antonio Moreda-Piñeiro Pilar Bermejo-Barrera Antonio Martin-Esteban 《Microchemical Journal》2009,(2):225-231
A new ionic imprinted polymer (IIP) for Ni(II) recognition/pre-concentration was prepared via precipitation polymerization using 2-(diethylamino) ethyl methacrylate (DEM) and divinylbenzene (DVB) as a crosslinking agent in the presence of nickel(II) and 5-vynil-8-hydroxyquinoline (5-VHQ) as a bi-functionalized ligand. An important increase on the selectivity of the synthesised IIP for nickel(II) ions was obtained when comparing to the use of 8-hydroxyquinoline (8-HQ) as a ligand. The synthesised IIP was used as a new support for solid phase extraction (SPE) of nickel(II) from seawater before inductively coupled plasma optical emission spectrometry (ICP-OES) detection. Variables affecting the SPE process, such as pH, load and elution flow rates, and concentration and volume of the eluting solution, were fully evaluated. The optimised procedure consists of a sample loading (100 mL of seawater at a pH of 9.0 ± 0.1) through IIP-SPE cartridges containing 300 mg of the synthesised IIP at a flow rate of 3.0 mL min− 1. Elution was performed by passing 2.5 mL of 2.0 M nitric acid at a flow rate of 1.5 mL min− 1, which gave a pre-concentration factor of 40. The limit of detection (LOD) of the method was 0.26 µg L− 1, while the relative standard deviation (RSD) for eleven replicated measurements was 3%. Accuracy of the method was assessed by analyzing SLEW-3 (estuarine water) and TM-23.3 (lake water) certified reference materials. In addition to the selectivity of the synthesised material for nickel(II) ions against other transition metal ions and major alkaline and alkaline-earth metals (Na+, K+, Mg2+ and Ca2+) in seawater, it can be stated that the salt matrix is efficiently removed by using the proposed IIP-SPE procedure. 相似文献
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D. Agbaba A. Mihajlovic P. Beljanski D. Zivanov-Stakic S. Vladimirov 《Chromatographia》1997,45(1):145-148
Summary TLC and HPLC methods for the determination of the preservative, 8-hydroxyquinoline sulfate in PPD-T tuberculin solution were
developed. The planar chromatography method involved separation of 8-hydroxyquinoline sulfate on a TLC plate using a butyl-acetate:
formic acid: 2-propanol mobile phase, detection and quantitation by densitometric scanning. The HPLC method was on a LiChrosorb
RP-18 column with acetonitrile-water (65:35 v/v) mobile phase, adjusted to pH 3.05 by phosphoric acid. Linearity, reproducibility
and accuracy were found to be satisfactory. Under selected conditions, the limit of detection (LOD) of both methods was similar-about
25 ng.
Presented at the 21st ISC held in Stuttgart, Germany, 15th–20th September, 1996 相似文献
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Summary Nitroxoline (8-hydroxy-5-nitroquinoline) and the structural related compounds 8-hydroxyquine, 8-hydroxy-5,7-dinitroquinoline,
and 8-hydroxy-5-nitrosoquinoline have been investigated by reversed-phase high-performance liquid chromatography on C18/ODS. Complete separation and symmetric, peaks were obtained by use of THF-methanol-water, 3∶3∶4, containing 10 mmol L−1 disodium ethylenediamine tetraacetic acid (EDTA) and 10 mmol L−1 citric acid in the water, as mobile phase. The pH and the concentration of EDTA in the mobile phase were found to be critical
for eliminating tailing and for full separation. The calibration plot was linear for concentrations between 3.0 and 300 μg
mL−1; the regression coefficient was 0.99996. Assay of the nitroxoline standard showed that recovery was from 99.3 to 102%, with
a mean standard deviation for nitroxoline of 0.9%. The method is suitable for quality control of nitroxoline. 相似文献
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K. M. Dyumaev E. P. Popova I. F. Mikhailova L. I. Shibaeva L. D. Smirnov 《Chemistry of Heterocyclic Compounds》1974,10(6):699-701
The nitration of 3-hydroxyquinoline with concentrated nitric acid in sulfuric acid at ?30 to +30°C gives 5-nitro-3-hydroxyquinoline (85–92%) and 7-nitro-3-hydroxyquinoline (7–12%). 4-Nitro-3-hydroxyquinoline is formed in 70% yield by nitration in acetic acid. 4,5-Dinitro-3-hydroxyquinoline is formed by further nitration of 4- and 5-nitro-3-hydroxyquinolines. 相似文献
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Electrochemical oxidation of 8-hydroxyquinoline at a lead dioxide anode in sulfuric acid gives quinolinic acid, which is decarboxylated to nicotinic acid. 相似文献
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Hongzhen Lian Danni Li Sizhu Mei Xiaojiang Wu Xiancong Tao Yijun Chen Lemei Dai Ning Gan Liching Tian 《Analytica chimica acta》2004,511(1):25-31
A novel strategy for the speciation of aluminum has been developed by fluorometry using selective analytical reagents under different pH conditions, which is based on the measurement of the complexation ability of Al for analytical reagents and native organic matters. With Eriochrome Blue Black R, labile monomeric Al and total monomeric Al fractions are determined at pH 4.5 and pH 8.0, respectively. With morin only the labile monomeric Al is determined at pH 4.0, while with 8-hydroxyquinoline the total monomeric Al is determined at pH 5.5. So, acid soluble Al fraction is obtained indirectly. This method is successfully applied to the fractionation of Al in natural waters. The results well agree with those obtained by Driscoll’s 8-hydroxyquinoline/cation-exchange protocol. This fluorometric method possesses some advantages such as high sensitivity, easy manipulation, no separation step and less time-consuming. 相似文献
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8-羟基喹啉与许多金属元素(除碱金属外),在弱酸性或弱碱性溶液中能形成螯合物沉淀,这种沉淀分子量大,组成恒定。试样以硝酸和氢氟酸溶解,EDTA为掩蔽剂,在乙酸铵-乙酸(pH=6.5)的缓冲溶液中,8-羟基喹啉与钨生成黄色沉淀,灼烧称重无水WO3。分别对沉淀时pH值、陈化时间、沉淀剂的用量进行选择,研究出了一种快速、准确、经济的分析方法。分析准确度好、精密度高,完全能够满足生产分析要求。 相似文献
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A. A. Isaev O. I. Lomovskii K. G. Koralev R. K. Karimov 《Chemistry of Natural Compounds》2004,40(3):266-268
The physicochemical consequences of mechanical treatment of 5-nitro-8-hydroxyquinoline with natural polymers cellulose, pectin, and -cyclodextrin were studied in order to improve its properties. It was found that particle sizes of the medicinal compound in the agglomerated mechanical-composite materials increased. The particle-size increase of the medicinal compound was avoided by adding a third component differing from 5-nitro-8-hydroxyquinoline by the acid-base properties and containing calcium carbonate. 相似文献
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在8-羟基喹啉存在下,分别采用水相法和两相法简便合成了5种取代水杨酸二茂钛配合物,并用元素分析、IR及 1H NMR等手段对配合物进行了结构表征,发现配合物中均不含8-羟基喹啉配体,而是形成以取代水杨酸为双齿配体的六元杂环化合物.用电子吸收光谱分别对两相反应体系(H2O/CHCl3)的水相和有机相进行了动态监测,发现8-羟基喹啉首先通过两相界面与有机相中的二氯二茂钛形成水溶性的过渡性配合物,然后该过渡性配合物再与有机相中的取代水杨酸作用形成了目标配合物. 相似文献
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LI Zhi-Feng ZHU Yuan-Cheng YUAN Kun KANG Jing-Wan 《结构化学》2008,27(1):63-69
The structures of 2,7'-(ethylene)-bis-8-hydroxyquinoline and its derivatives were optimized at the ground states using ab initio HF and B3LYP methods. At the same time, the molecular structures of the first singlet excited state for 2,7'-(ethylene)-bis-8-hydroxyqulnoline and its derivatives were optimized by CIS/6-31G(d). The absorption and emission spectra based on the above structures were obtained by the time-dependent density functional theory (TD-DFT) by the B3LYP method with the 6-31G(d) basis set. The calculated results of luminescence originate from the electronic transition from the hydroxphenol ring of 8-hydroxyquinoline A to the pyridine ring of 8-hydroxyquinoline B. Their luminescence wave bands can be tuned by different substituents on the ligand of 8-hydroxyquinoline. 相似文献
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The structures of 2,7′-(ethylene)-bis-8-hydroxyquinoline and its derivatives were optimized at the ground states using ab initio HF and B3LYP methods. At the same time, the molecular structures of the first singlet excited state for 2,7′-(ethylene)-bis-8-hydroxyquinoline and its derivatives were optimized by CIS/6-31G(d). The absorption and emission spectra based on the above structures were obtained by the time-dependent density functional theory (TD-DFT) by the B3LYP method with the 6-31G(d) basis set. The calculated results of luminescence originate from the electronic transition from the hydroxphenol ring of 8-hydroxyquinoline A to the pyridine ring of 8-hydroxyquinoline B. Their luminescence wave bands can be tuned by different substituents on the ligand of 8-hydroxyquinoline. 相似文献
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《Journal of Coordination Chemistry》2012,65(7):1019-1026
Two nano-structural complexes, bis-(8-hydroxyquinoline) cobalt and bis-(8-hydroxyquinoline) nickel, have been prepared by one-step, low-heating, solid-state reaction, a simple, safe, economical and environmentally-friendly method. TEM and SEM images show that the complexes are composed of nanobelts with width ranging from 100 to 300?nm and a length of up to 1?µm. The technique offers a new way for fabricating coordination compounds with one-dimensional nanostructure. 相似文献