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11.
A glassy carbon electrode was modified with electropolymerized film of diphenylamine sulfonic acid (DPASA). Electropolymerization was performed by cyclic voltammetry in 0.1 M KCl solution. The modified electrode showed an excellent
electrocatalytic effect towards oxidation of dopamine (DA) and ascorbic acid (AA). Electrostatic interaction between the negatively charged poly(DPASA) film and either cationic DA species or anionic AA
species favorably contributed to the redox response of DA and AA. Anodic peaks of DA and AA in their mixture were well separated
by ca 168 and −11.8 mV. The proposed modified electrode was utilized for selective determination of dopamine in the concentration
range of 5.0 × 10t7–2.0 × 10−5 M in the presence of high concentration of ascorbic acid. Detection limit was 6.5 × 10−9 M. 相似文献
12.
A Collaboration M. Makek P. Achenbach C. Ayerbe Gayoso C. Barbieri J. C. Bernauer R. B?hm D. Bosnar A. Denig M. O. Distler I. Fri??i? C. Giusti H. Merkel U. Müller L. Nungesser J. Pochodzalla S. Sanches Majos B. S. Schlimme M. Schwamb Th. Walcher 《The European Physical Journal A - Hadrons and Nuclei》2016,52(9):298
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Slobodan??iri?Email authorView authors OrcID profile Violeta?Miti? Sne?ana?Jovanovi? Marija?Ili? Jelena?Nikoli? Gordana?Stojanovi? Vesna?Stankov Jovanovi? 《Mikrochimica acta》2018,185(12):556
The authors report on a novel sorbent (thermally treated natural zeolite; clinoptilolite) for use in dispersive micro-solid phase extraction (D-μ-SPE) of polycyclic aromatic hydrocarbons (PAHs) from water samples. The method was applied to the D-μ-SPE of 16 priority PAHs which then were quantified by gas chromatography with mass spectrometric detection (GC-MS). The method was validated in terms of specificity and selectivity, linearity and linear range, accuracy, precision, uncertainty, limits of detection and quantification. Figures of merit include (a) linear analytical ranges between 2.08 and 208 ppb, and (b) detection limits in the range from 0.01 to 0.92 ppb. The method was successfully applied to the determination of PAHs in river waters. 相似文献
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Yener Suayb Cagri Yener Tuba Mutlu Resat 《Journal of Thermal Analysis and Calorimetry》2018,134(2):1243-1252
Journal of Thermal Analysis and Calorimetry - In this paper, the current, voltage and temperature of the container of an electric current-activated/assisted sintering (ECAS) system are measured and... 相似文献
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Krystyna?Bogdanowicz-SzwedEmail author Jacek?Grochowski Ma?gorzata?Krasodomska Pawe??Serda 《Monatshefte für Chemie / Chemical Monthly》2004,135(2):201-209
Summary. The condensation of two molecules of 2-(2-thienylcarbonyl)thioacetanilides catalyzed by piperidine yielded thiazole derivatives as confirmed by X-ray crystal structure analysis. The reaction of malononitrile with 3-morpholino-3-(2-thienyl)acrylic acid thioanilides furnished 6-amino-1-aryl-4-(2-thienyl)-1,2-dihydro-2-thioxopyridine-5-carbonitriles. A similar reaction of malononitrile with 3-morpholino-3-(2-thienyl)acrylic acid anilides provided 2-oxopyridine-5-carbonitriles. 相似文献
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Tuncer??aykaraEmail author Recai??nam Zülfiye??ztürk Olgun?Güven 《Colloid and polymer science》2004,282(11):1282-1285
The formation of metal complexes between water-soluble polymers, poly(vinyl alcohol) [PVA], poly(N-vinylpyrrolidone) [PVP], poly(acrylamide) [PAAm] and poly(ethylene oxide) [PEO] with trivalent metal ions, Fe3+, Cr3+, and V3+ were studied by using differential pulse polarography (DPP). The general experimental observation is the shift of totally reversible reduction peaks (M3++Hg+e–M2++Hg) towards more negative potentials when the complexing water-soluble polymers are added to the solution of trivalent metal ions. The negative shift in potential permitted the determination of complex formation constants (Kf) between trivalent metal ions and water soluble polymers. The complex formation constants for Fe3+, Cr3+, and V3+ ions with these polymers increased in the order of V3+>Cr3+>Fe3+. 相似文献
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Spevácková V Korunová V Cejchanová M Vobecký M 《Analytical and bioanalytical chemistry》2004,380(2):346-350
A sampling procedure appropriate for the determination of mercury in whole blood was tested by using both inactive controls and a 197Hg mercury radio-indicator. To exclude the influence of the instrumental device (an AMA 254 single-purpose mercury atomic absorption spectrometer) on the determination of mercury in whole blood, the function of the instrument was checked by using rat blood with metabolised 197Hg. The measurement procedure was found to be free of errors. However, the study showed that the material used for the sampling vessels is a crucial parameter for obtaining accurate analytical results. The stability of solutions and samples was tested towards polyethylene (PE) and polypropylene (PP) vessels. PE displayed a time-dependent increase in the mercury content both in the samples and in the blood control material. The probable cause of this increase was direct contamination from the material of the vessel and/or diffusion of mercury from the environment through the vessel walls related to a strong complexing affinity of the sample matrix. This assumption was confirmed by supplying the vessels with the complexing agent Na2EDTA (0.05 mol L–1). Commercial PP vessels for blood sampling (Sarstedt S-Monovette Metall Analytik) did not give rise to statistically significant variations in mercury content in the samples and blood control material over a 30-day period. 相似文献