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This review aims to provide an overview of homogeneous liquid-liquid extraction (HLLE) and dispersive liquid-liquid microextraction (DLLME) methods and their potential use in inorganic analysis. Relevant applications to the determination of metal ions, metalloids and organometals are included. The phase separation mechanisms of these unconventional solvent extraction techniques are discussed. The new trends in the field of miniaturization and automation are presented, while proposing future trends and potential new areas for their application. 相似文献
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Konstantina Roussou Alexandros K. Nikolaidis Fani Ziouti Aristidis Arhakis Konstantinos Arapostathis Elisabeth A. Koulaouzidou 《Molecules (Basel, Switzerland)》2021,26(16)
Over the last years, diverse commercial resin-based composites have dominated as dental filling materials. The purpose of the present study was to determine organic and inorganic eluates from five restorative materials using GC/MS and ICP–OES and to compare the effect on cell survival of human gingival fibroblasts of a conventional and a bioactive resin. Five commercially available restorative materials were employed for this study: ActivaTM Bioactive Restorative, ENA HRi, Enamel plus HRi Biofunction, Fuji II LC Capsule, and Fuji IX Capsule. Disks that were polymerized with a curing LED light or left to set were immersed in: 1 mL methanol or artificial saliva for GC/MS analysis, 5mL deionized water for ICP–OES, and 5mL of culture medium for cell viability. Cell viability was investigated with a modified staining sulforhodamine B assay.The following organic substances were detected: ACP, BHT, BPA, 1,4-BDDMA, CQ, DBP, DMABEE, HEMA, MCE, MeHQ, MOPA, MS, TMPTMA, and TPSb and the ions silicon, aluminum, calcium, sodium, and barium. Activa Bioactive Restorative was found to be biocompatible. Elution of organic substances depended on material’s composition, the nature of the solvent and the storage time. Ions’ release depended on material’s composition and storage time. The newly introduced bioactive restorative was found to be more biocompatible. 相似文献
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Vasilis G. Salis Sotirios A. Mallios Ioannis G. Tigelis Aristidis S. Theodorou 《International Journal of Infrared and Millimeter Waves》2007,28(4):291-298
Optimized models for 90° polarization shift step twists for Ku, K and Ka bands are presented. The cross-section of the waveguide
employed is similar to that of a rectangular one, with the difference that the walls of the shorter side are part of a circular
one with the proper diameter. The optimized models have been found using the CST Microwave Studio simulation tool and in all
cases the return loss is kept below -20 dB for a wide range of frequency spectrum. Two examples are given, one for Ku band
and the other for K and Ka ones. 相似文献
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Aristidis N. Anthemidis Constantina MitaniPaschalia Balkatzopoulou Paraskevas D. Tzanavaras 《Analytica chimica acta》2012
A simple and fast preconcentration/separation dispersive liquid–liquid micro extraction (DLLME) method for metal determination based on the use of extraction solvent with lower density than water has been developed. For this purpose a novel micro-volume introduction system was developed enabling the on-line injection of the organic solvent into flame atomic absorption spectrometry (FAAS). The effectiveness and efficiency of the proposed system were demonstrated for lead and copper preconcentration in environmental water samples using di-isobutyl ketone (DBIK) as extraction solvent. Under the optimum conditions the enhancement factor for lead and copper was 187 and 310 respectively. For a sample volume of 10 mL, the detection limit (3 s) and the relative standard deviation were 1.2 μg L−1 and 3.3% for lead and 0.12 μg L−1 and 2.9% for copper respectively. The developed method was evaluated by analyzing certified reference material and it was applied successfully to the analysis of environmental water samples. 相似文献
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Natalia Manousi Abuzar Kabir Kenneth G. Furton George A. Zachariadis Aristidis Anthemidis 《Molecules (Basel, Switzerland)》2021,26(15)
A sol-gel thiocyanatopropyl-functionalized silica sorbent was synthesized and employed for an automated on-line microcolumn preconcentration platform as a front-end to inductively coupled plasma atomic emission spectroscopy (ICP-AES) for the simultaneous determination of Cd(II), Pb(II), Cu(II), Cr(III), Co(II), Ni(II), Zn(II), Mn(II), Hg(II), and V(II). The developed system is based on an easy-to-repack microcolumn construction integrated into a flow injection manifold coupled directly to ICP-AES’s nebulizer. After on-line extraction/preconcentration of the target analyte onto the surface of the sorbent, successive elution with 1.0 mol L−1 HNO3 was performed. All main chemical and hydrodynamic factors affecting the effectiveness of the system were thoroughly investigated and optimized. Under optimized experimental conditions, for 60 s preconcentration time, the enhancement factor achieved for the target analytes was between 31 to 53. The limits of detection varied in the range of 0.05 to 0.24 μg L−1, while the limits of quantification ranged from 0.17 to 0.79 μg L−1. The precision of the method was expressed in terms of relative standard deviation (RSD%) and was less than 7.9%. Furthermore, good method accuracy was observed by analyzing three certified reference materials. The proposed method was also successfully employed for the analysis of environmental water samples. 相似文献
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Aristidis N. Anthemidis 《光谱学快报》2013,46(6):699-711
Abstract A simple online sequential insertion manifold coupled to a hydride generation atomic absorption spectrometer (HG‐AAS) has been developed for selective inorganic Se(IV) determination. The online method is based on the sequential insertion of sample and reagents in the integrated reaction chamber gas–liquid separator (RC‐GLS), which operates initially as reaction chamber for various sample volumes (up to 20 mL) and subsequently as gas–liquid separator with limited dead volume. The generated hydride from a large sample volume is trapped in the RC‐GLS for a short time and then it is flashed in the atomic absorption cell. The HCl and the NaBH4 concentration was optimized for selective inorganic Se(IV) determination. For 8‐mL and 16‐mL sample consumption, the sampling frequency is 40 h?1 and 24 h?1, while the detection limit is 0.04 µg L?1 and 0.03 µg L?1, respectively. The precision (relative standard deviation) for 2.0 µg L?1 Se(IV) (n=10) is 2.6% and 2.8% for 8 mL and 16 mL sample volumes, respectively. The accuracy of the proposed method was evaluated by analyzing the certified reference material, NIST CRM 1643d, and also by analyzing spiked natural water. 相似文献
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