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821.
Accurate and sensitive determination of vanillin in commercial samples is significant for food safety & quality. In the proposed study, copper particles were coated on an indium tin oxide electrode (ITO) by cyclic voltammetry (CV) for the determination of vanillin in food samples. CV studies indicated that the electrodeposition of Cu particles provides a good electrocatalytic effect towards the oxidation of vanillin. The fabricated sensor determines vanillin linearly between 0.50 μM–2.0 mM (Limit of detection: 0.15 μM). The Cu/ITO was successfully tested on vanillin samples and the recommended method provides accurate and selective determination of vanillin in daily samples. 相似文献
822.
Russian Journal of Coordination Chemistry - A new indole-based biphenyldiamine derivative was synthesized, characterized and a Hg(II) cations sensing application was performed. Within the possible... 相似文献
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825.
For the computation of the macroscopic tangent that is required in multiscale volumetric homogenization techniques, two methods are summarized. First, a condensation approach is followed where the linearity of variational terms associated with the penalty enforcement of boundary conditions is explored in order to extract a macroscopic tangent at any stage of the Newton–Raphson iterations of a microstructural testing procedure. As an alternative approach, a second method is explored that requires only the knowledge of infinitesimally close macroscopic deformation states. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
826.
Two different classes of drugs were selected to test the adsorption capacity of carbon nanofibers as a greener new generation alternative adsorbent in simulated gastric and intestinal fluids. Kinetics of the promethazine and trimethoprim adsorption were analyzed using Lagergren first order and Pseudo second order models. Intraparticle diffusion graphs were also plotted to discuss the adsorption mechanism. Kinetic data showed the significance of boundary layer effect for both of the drugs and the presence of intraparticle diffusion as the other rate controlling step for the promethazine adsorption. Giles isotherms showed the high affinity of drug molecules to the adsorbent. Maximum adsorption capacity of drugs was calculated using Langmuir model as 18.35 and 41.15 mg/g for trimethoprim and 95.24 and 80.65 mg/g for promethazine in simulated gastric fluid (SGF) and simulated intestinal fluid (SIF), respectively. Trimethoprim adsorption was under favor of hydrophobic interaction and π-π dispersion interactions while promethazine adsorption was through cation exchange where the electrostatic attraction is an important force with the contribution of dispersion interactions. 相似文献
827.
Tugberk Tabak Kerem Kaya Recep Isci Turan Ozturk Yusuf Yagci Baris Kiskan 《Macromolecular rapid communications》2024,45(2):2300455
A novel method based on light-induced fabrication of a poly (3,4-ethylenedioxythiophene)-polycaprolactone (PEDOT-PCL) scaffold using phenacyl bromide (PAB) as a single-component photoinitiator is presented. HBr released from the step-growth polymerization of EDOT is utilized as an in situ catalyst for the chain-growth polymerization of ε-caprolactone. Detailed investigations disclose the formation of a self-assembled nanoporous electroconductive scaffold (1.2 mS cm−1). Fluorescence emission spectra of the fabricated scaffold exhibit a mixed solvatochromic behavior, indicating specific interactions between the self-assembled scaffold and solvents with varying polarities, as evidenced by transmission electron microscopy (TEM). Moreover, the same light-induced technique can also be applied for bulk photopolymerization showcasing the versatility and wide-ranging scope of the originated method. In brief, this study introduces a novel approach for light-induced polymerization reactions that is merging step-growth and chain-growth mechanisms. This innovative approach is promising to facilitate in situ polymerization of monomers possessing diverse functionalities. 相似文献